Metrics details Moving battery technology from the laboratory to large-scale production is a necessary step in achieving cost competitiveness for high-energy-density batteries academic research has focused on the active material of the electrode and little attention has been paid to cell-level design upscaling high-areal-capacity electrode sheets is proposed as a practical way forward Here we evaluate the impact of high-areal-capacity electrodes on cell energy densities energy consumption during electrode fabrication and the cost efficiency of cell production By examining the integration of scalable roll-to-roll electrode-manufacturing techniques (such as slurry casting and dry coating) with the materials chemistry of the electrode components electrode structure design and cell performance we aim to outline the areas of development for high-areal-capacity electrodes and provide a structured pathway for bridging the gap between laboratory innovations and industrial scale-up Prices may be subject to local taxes which are calculated during checkout Performance and cost of materials for lithium-based rechargeable automotive batteries This paper discusses the development of the entire battery value chain for EV applications Pathways for practical high-energy long-cycling lithium metal batteries Promise and reality of post-lithium-ion batteries with high energy densities Regulating electrostatic phenomena by cationic polymer binder for scalable high-areal-capacity Li battery electrodes Graphene collage on Ni-rich layered oxide cathodes for advanced lithium-ion batteries Bridging the academic and industrial metrics for next-generation practical batteries From fundamental understanding to engineering design of high‐performance thick electrodes for scalable energy‐storage systems This paper summarizes the current academic studies of high-areal-capacity electrodes on a laboratory scale From laboratory innovations to materials manufacturing for lithium-based batteries This paper discusses the knowledge gap between the laboratory-scale synthesis of materials and the mass production of them Battery Performance and Cost Modeling for Electric-Drive Vehicles: A Manual for BatPaC v5.0 (Argonne National Laboratory Progress in solvent-free dry-film technology for batteries and supercapacitors A 5 V-class cobalt-free battery cathode with high loading enabled by dry coating Solvent-free manufacturing of electrodes for lithium-ion batteries Nanotextile 100% Si anodes for the next generation energy‐dense Li‐ion batteries the rising star in solid-state battery industrialization This paper discusses the development of dry electrode fabrication technology 3D printing of customized Li‐ion batteries with thick electrodes vertical‐channeled thick electrodes with high rate and cycle performance low‐tortuosity carbon frameworks as ultrathick 3D current collectors Ultrahigh-capacity and scalable architected battery electrodes via tortuosity modulation Investigation of edge formation during the coating process of Li-ion battery electrodes Capillary flow as the cause of ring stains from dried liquid drops Slot die coating of lithium-ion battery electrodes: investigations on edge effect issues for stripe and pattern coatings Classification of calendering‐induced electrode defects and their influence on subsequent processes of lithium‐ion battery production Investigation of film solidification and binder migration during drying of Li-ion battery anodes Distribution of particles during solvent evaporation from films Structure formation in soft‐matter solutions induced by solvent evaporation Drying of lithium-ion battery anodes for use in high-energy cells: influence of electrode thickness on drying time gel electrolyte-embedded high-mass-loading cathodes for high-energy lithium metal batteries High areal capacity battery electrodes enabled by segregated nanotube networks Alternative binders for sustainable electrochemical energy storage–the transition to aqueous electrode processing and bio-derived polymers Current status and challenges for automotive battery production technologies Roll-to-roll prelithiation of lithium-ion battery anodes by transfer printing Effects of electrode curvature in Li-ion cells Mechano‐graded electrodes mitigate the mismatch between mechanical reliability and energy density for foldable lithium‐ion batteries 21700 Li-ion cells – a direct comparison of electrochemical 10 mAh cm−2 cathode by roll‐to‐roll process for low cost and high energy density Li‐ion batteries Understanding interfacial‐energy‐driven dry powder mixing for solvent‐free additive manufacturing of Li‐ion battery electrodes Methods for the calculation of surface free energy of solids Ozone-treated carbon nanotube as a conductive agent for dry-processed lithium-ion battery cathode A polytetrafluoroethylene-based solvent-free procedure for the manufacturing of lithium-ion batteries Deformation capability of poly(tetrafluoroethylene) materials: estimation with X-ray diffraction measurements Process modeling of the electrode calendering of lithium-ion batteries regarding variation of cathode active materials and mass loadings Capacity fading of Ni-rich Li[NixCoyMn1−x−y]O2 (0.6 ≤ x ≤ 0.95) cathodes for high-energy-density lithium-ion batteries: bulk or surface degradation Critical parameters for evaluating coin cells and pouch cells of rechargeable Li-metal batteries Investigation of the mechanical behavior of electrodes after calendering and its influence on singulation and cell performance Impedance spectroscopy characterization of porous electrodes under different electrode thickness using a symmetric cell for high-performance lithium-ion batteries Multiscale understanding and architecture design of high energy/power lithium‐ion battery electrodes Influence of convective drying parameters on electrode performance and physical electrode properties Thick electrodes for Li-ion batteries: a model based analysis Comparison of modeling predictions with experimental data from plastic lithium ion cells Berechnung verschiedener physikalischer Konstanten von heterogenen Substanzen Dielektrizitätskonstanten und Leitfähigkeiten der Mischkörper aus isotropen Substanzen Quantifying tortuosity in porous Li-ion battery materials Understanding capacity fading mechanism of thick electrodes for lithium-ion rechargeable batteries Influence of the boundaries in the impedance of porous film electrodes Theoretical and experimental analysis of porous electrodes for lithium-ion batteries by electrochemical impedance spectroscopy using a symmetric cell Modeling of galvanostatic charge and discharge of the lithium/polymer/insertion cell Optimizing areal capacities through understanding the limitations of lithium-ion electrodes The concept of effective porosity in the discharge rate performance of high-density positive electrodes for automotive application Failure mode of thick cathodes for Li-ion batteries: variation of state-of-charge along the electrode thickness direction Unveiling the dimensionality effect of conductive fillers in thick battery electrodes for high-energy storage systems Resolving the discrepancy in tortuosity factor estimation for Li-ion battery electrodes through micro-macro modeling and experiment Mechanical and structural degradation of LiNixMnyCozO2 cathode in Li-ion batteries: an experimental study Tailoring grain boundary structures and chemistry of Ni-rich layered cathodes for enhanced cycle stability of lithium-ion batteries Rational design of mechanically robust Ni-rich cathode materials via concentration gradient strategy Boosting reaction homogeneity in high‐energy lithium‐ion battery cathode materials A perspective on single-crystal layered oxide cathodes for lithium-ion batteries Tortuosity estimation and microstructure optimization of non-uniform porous heterogeneous electrodes Mitigating the kinetic hindrance of the poly/single-crystalline Ni-rich cathode-based electrode via formation of the superior electronic/ionic pathway Electronically conductive phospho-olivines as lithium storage electrodes Direct measurements of effective ionic transport in porous Li-ion electrodes Tortuosity anisotropy in lithium-ion battery electrodes Multiscale dynamics of charging and plating in graphite electrodes coupling operando microscopy and phase-field modelling Impact of spheroidization of natural graphite on fast-charging capability of anodes for LIB Issues impeding the commercialization of laboratory innovations for energy-dense Si-containing lithium-ion batteries Highly elastic binders integrating polyrotaxanes for silicon microparticle anodes in lithium ion batteries Enhancing hydrophilicity of thick electrodes for high energy density aqueous batteries Introduction to Percolation Theory (Taylor & Francis Correlations between percolation threshold Quantifying the effect of electronic conductivity on the rate performance of nanocomposite battery electrodes Perspective on carbon nanotubes as conducting agent in lithium-ion batteries: the status and future challenges Significance of current collectors for high performance conventional lithium‐ion batteries: a review Ultrahigh loading dry-process for solvent-free lithium-ion battery electrode fabrication Lightweight polymer–carbon composite current collector for lithium-ion batteries Ultralight and fire-extinguishing current collectors for high-energy and high-safety lithium-ion batteries Fast and reversible thermoresponsive polymer switching materials for safer batteries Large-scale current collectors for regulating heat transfer and enhancing battery safety A non-academic perspective on the future of lithium-based batteries This paper discusses the importance of integrating an understanding of industrial processes into academic research for advancing TRLs Development of a feasible and scalable manufacturing method for PTFE-based solvent-free lithium-ion battery electrodes Binder migration during drying of lithium-ion battery electrodes: modelling and comparison to experiment Binder migration: frequently observed yet overlooked phenomena in electrode processing for lithium-ion batteries Improvement of lithium‐ion battery performance by two‐layered slot–die coating operation Experimental and simulation investigations of porosity graded cathodes in mitigating battery degradation of high voltage lithium-ion batteries Multi-length scale microstructural design of lithium-ion battery electrodes for improved discharge rate performance Magnetically aligned graphite electrodes for high-rate performance Li-ion batteries Insight on electrolyte infiltration of lithium ion battery electrodes by means of a new three-dimensional-resolved lattice Boltzmann model Electrocapillary boosting electrode wetting for high-energy lithium-ion batteries Hard-carbon-stabilized Li–Si anodes for high-performance all-solid-state Li-ion batteries Download references This work was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (RS-2024-00344021 and RS-2024-00455177) and LG Energy Solution acknowledges the support from the Center for Mesoscale Transport Properties an Energy Frontier Research Center supported by the US Department of Energy as well as from the Welch Foundation F-1861 These authors contributed equally: Jung-Hui Kim Department of Chemical and Biomolecular Engineering Materials Science and Engineering Program and Walker Department of Mechanical Engineering investigated the industrial electrode manufacturing processes performed the specific energy and cost analyses of the cells conducted the theoretical calculations of cell performance conducted the literature studies on slurry-cast electrode processing carried out the literature studies on dry-coated electrode processing performed the literature studies on alternative electrode-processing methods All authors contributed to the writing and revision of the manuscript The authors declare no competing interests Matthew Li and Moumita Rana for their contribution to the peer review of this work Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law Reprints and permissions Download citation DOI: https://doi.org/10.1038/s41560-025-01720-0 Anyone you share the following link with will be able to read this content: a shareable link is not currently available for this article Sign up for the Nature Briefing newsletter — what matters in science Revolutionary sound technology from Tomorrowland is making waves at CES showcasing its potential to redefine live events and at the ongoing Consumer Electronics Show (CES) in Vegas the music festival juggernaut is making fresh waves rippling far beyond the DJ booth Belgium-based festival brand is making a big statement with AREAL Introduced to a global audience at the "Caliverse" booth AREAL exemplifies a cutting-edge convergence of art Since its initial testing at Tomorrowland's groundbreaking Atmosphere stage in 2019 The technology is said to offer a richer sound experience with reduced noise pollution lower decibel levels and enhanced auditory health its potential applications extend far beyond live music to cinema making it a potential solution for a wide range of immersive audio needs 2025The technology doesn't just cater to large venues AREAL has additionally introduced headphones designed for individual listeners combining true multi-driver speaker setups with its proprietary algorithms. The headphones are said to deliver an unparalleled spatial audio 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Metrics details How biological neural networks reliably process information in the presence of spontaneous activity remains controversial stimulus-evoked and spontaneous activity show orthogonal (dissimilar) patterns which is advantageous for separating sensory signals from internal noise have reported high similarity between stimulus-evoked and spontaneous activity the mechanism of signal-noise separation in the columnar visual cortex may be different from that in rodents we compared spontaneous and stimulus-evoked activity in marmoset V1 and higher visual areas spontaneous and stimulus-evoked activity showed similar patterns as expected spontaneous and stimulus-evoked activity were progressively orthogonalized along the cortical hierarchy eventually reaching levels comparable to those in mouse V1 These results suggest that orthogonalization of spontaneous and stimulus-evoked activity is a general principle of cortical computation the fact that both sets of studies were conducted only on V1 makes it difficult to extend these results to general cortical computations if spontaneous and evoked activities share similar patterns in all the visual areas of carnivores/primates it would be of great interest to determine how the cortical network could distinguish between stimulus-related information from internally generated noise To systematically characterize the spatiotemporal patterns of spontaneous activity across the marmoset visual areas we used a newly developed primate-optimized expression system of genetically encoded calcium indicators (Hashimoto et al. these results suggest that the patchy activity pattern is a canonical mode of spontaneous activity in the primate neocortex a Two-photon calcium imaging is conducted in visual areas identified from widefield imaging spontaneous and visually evoked activity is recorded for the identical set of cells b Example cell image and cellular orientation map in V1 Experiments were repeated in 12 times and similar results were obtained The cellular orientation map is calculated using the cells identified from the cell image (left) c Time courses of spontaneous activity for example cells Comparison of spontaneous and evoked activity in V1 (d) Timecourses” shows a correlation between individual spontaneous frames and responses to single orientations or directions Panel “FOV Activity” shows the average activity of all the cells in the FOV Resp.” show an example spontaneous frame and a response to a single orientation that is most similar to the spontaneous frame Two examples are shown for time points indicated by dotted lines in the time courses g Cumulative plots showing the similarity of spontaneous frames and evoked activity correlations with all single orientation or direction responses are calculated a summary table of statistically significant difference [* p < 0.05 (corrected by Bonferroni’s method) the correspondence did not apply to downstream area MT suggesting that the relationship between spontaneous and evoked activity varies across cortical areas a Overview of the analysis based on cellular-level neural activity data recorded by two-photon imaging Trial-averaged visual responses are projected to a space spanned by spontaneous activity to obtain activity patterns shared by spontaneous and evoked activity (Shared Activity) Trial-averaged visual responses are orthogonalized to the space spanned by spontaneous activity to activity patterns specific to stimulus-evoked activity (Stim-Only Activity) Spontaneous activities were orthogonalized to a space spanned by trial-averaged visual responses to obtain activity patterns specific to spontaneous activity (Sponta-Only Activity) b Examples of the 1st principal components (PCs; left panels blue-to-yellow colour) of activity patterns in the three activity-spaces a single condition visual response that is most similar is also shown (right Correlation coefficients between pairs of PC and visual response: V1 Shared (0.29) c Population data on the similarity between PCs and visual responses Horizontal lines indicate pairs with significant differences (p < 0.05 corrected by Bonferroni’s method for 6 pairwise comparisons) N numbers indicating number of FOVs are 12(V1) two-sided) are as follows: 0.339 (Stim-Only To quantify the contribution of the averaged signals to the total variance in single-trial neural activity, we performed a cross-validated regression of neural activity. In the marmosets V1, V2, MT and mouse V1, the percent of the total variance of single-trial activity explained by the averaged signals ranged between 30 and 50% (Supplementary Fig. 8) the trial-averaged neural activity explained a substantial fraction of the single-trial stimulus-evoked responses in all tested visual areas a Variance of cellular-level trial-averaged visual responses projected to the Shared subspace Horizontal lines indicate pairs with significant difference (p < 0.01 b Same as (a) but projected to individual PCs of Shared Space c Variance of single trial visual responses (left) and spontaneous activity (right) projected to each subspace and are same for all subspaces and trial-types Spontaneous and visually evoked activities in the primate visual cortex are progressively orthogonalized along the hierarchical network The degree of the orthogonality in the mouse V1 is similar to higher but not lower visual areas of the marmoset The estimated dimensionality of shared space, as quantified by the number of PCs with large projections of stimulus-related variance, showed a similar tendency to the amount of projected variance; the dimensionality of shared space was larger for marmosets V1 and V2 than for marmoset MT and mouse V1 (Supplementary Fig. 12a) the overlap between spontaneous and evoked activity progressively decreased along the cortical hierarchy these results suggest that the marmoset visual network achieves the separation of stimulus-related signal information and internally generated noise through processing in the hierarchical cortical areal network the presence of patchy spatial patterns may indicate that spontaneous activity propagates along cortico-cortical connections It is of great interest for future studies to examine whether the relationship between the spontaneous and evoked activity in the mouse V1 and the marmoset MT follows a similar developmental pattern It is likely that the anaesthetic condition used in the present study strongly attenuated this component of neuronal activity (in fact the variance projected to the 1st PC in our data was 8% whereas that in Stringer et al Because almost all of the visual areas are accessible for optical recording and manipulation the marmoset monkey is ideally suited for testing these hypotheses It is tempting to speculate that the difference in the site of orthogonalization in the marmoset and the mouse is related to the difference in the depth of the hierarchical cortical network in the two species: the marmoset with a deep cortical network may benefit initially parallel spontaneous activity whereas the mouse with a shallow cortical network benefit more by having orthogonalized spontaneous activity already at V1 despite the species difference in circuit-level implementations the orthogonalization of activity patterns is likely a common computational goal for separating sensory signals and internal noise in biological neural circuits A total of 12 adult common marmosets (Callithrix jacchus; 7 males and 5 females; body weight 1–2 years) obtained from Nihon Clea and four Thy1-GCaMP6 mice (4 males; GP 4.3 P50–60) obtained from Jackson Laboratory were used All animals were housed in a 12:12 h light-dark cycle had access to water and food ad libitum and were not used for other experiments before the present study All animal experiments were carried out following the institutional welfare guidelines laid down by the Animal Care and Use Committee of the University of Tokyo and approved by the Ethical Committee of the University of Tokyo 10 were used to obtain widefield imaging data [Large FOV covering the occipital-parietal cortex and nine were used to obtain two-photon imaging data [V1 Four mice were used to obtain the two-photon imaging data (12 FOVs in V1) pAAV-TRE-GCaMP6f-WPRE was used as a template for this plasmid AAV plasmids were packaged into AAV serotype 9 using the AAV Helper-Free system (Agilent Technologies) and pHelper plasmids were transfected into HEK293 cells AAV2/9 particles were purified using the AAV Purification kit (Takara The AAV solution was concentrated to the optimal volume by centrifugation using an Amicon Ultra-4 100k centrifugal filter unit (Millipore) The number of genomic copies was quantified with intercalating dyes (Thermo Fisher Scientific USA) and two sets of primers for WPRE or hGHpA genes The final titration of the AAV was estimated as relative quantitation according to a calibration curve calculated from the known numbers of copies of AAV plasmids All surgical procedures were performed under aseptic conditions Marmosets were anaesthetized with isoflurane (4.0–5.0% for induction and 1.5–3.0% for maintenance in a mixture of 20–50% O2 and air) percutaneous oxygen saturation (SpO2) and heart rate were monitored and maintained at >96% and <200 bpm The rectal temperature was maintained at 37 °C using an electric blanket and a feedback-controlled heating pad s.c.) was administered as an antibiotic prophylaxis s.c.) was administered to reduce pain and inflammation The scalp was sterilized with povidone-iodine All incision sites were pre-treated with local injections of lidocaine HCl (2%) or lidocaine jelly a custom-made metal head post was attached to the skull using dental acrylic (Shofu Inc.) Marmosets were then head-fixed on a custom-made metal stage using a head post 1–2 mm apart) were made around the targeted cortical regions and the dura mater was cut to expose the cortical surface The brain was washed with gentamycin-mixed artificial cerebrospinal fluid (ACSF) An AAV cocktail with a 1:1 mixture of AAV2/9-Thy1S-tTA (3.11 × 1013 vg/ml) and AAV2/9-TRE-tandem-GCaMP6s (2.65 × 1013 vg/ml) was loaded into a glass pipette and injected using a Nanoject III (Drummond Scientific Company) The pipette was inserted 300–500 µm below the cortical surface and 0.5–1.0 µl AAV was injected at 0.12 µl/min in a single injection site the craniotomies were covered with Kwik-SilTM (World Precision Instruments) All wound sites were treated with gentamycin ointment warmed physiological saline (5 ml) was administered subcutaneously to prevent dehydration and the animals were returned to their home cage for recovery meloxicam and/or ampicillin were/was administered for postoperative management The animals were maintained for 4–5 weeks before the imaging experiments to ensure sufficient GCaMP expression s.c.) was administered as an anti-inflammatory drug and the animal was mechanically ventilated End-tidal CO2 was monitored and kept at 3.4–4.0% throughout the experiment An intravenous catheter was placed in the femoral vein and anaesthesia was maintained by constant infusion of remifentanil (6.0–15.0 μg/kg/h i.v.) mixed in lactated Ringer’s solution (2.0 ml/kg/h) and dexamethasone (0.4 mg/kg/h) Muscle relaxation was induced by vecuronium bromide (0.1 mg/kg/h Additional doses of isoflurane (2.0%–3.0%) and N2O (50% in O2 and air) were administered intraoperatively A custom-made metal head post was attached to the skull and the animal was mounted on a stereotaxic apparatus A large cranial window was made over the targeted brain regions (12 mm diameter circle or 8 mm × 16 mm square A glass coverslip (10 mm in diameter or 8 mm × 16 mm square) attached to a custom-made metal rim was placed on the exposed cortical surface and the brain was sealed with Kwik-SilTM (World Precision Instruments) and dental cement (Sun Medical) anaesthesia was maintained by remifentanil (6.0–15.0 μg/kg/h and doses of isoflurane and N2O were decreased to 0–0.5% and 10–50% The eyes were covered with contact lenses and frequently moistened with an ophthalmic solution to ensure a clear view throughout the experiment In vivo wide-field imaging was performed using a macrozoom fluorescence microscope (MVX10 Olympus) equipped with a 2× objective (2x MVX Plan Apochromat Lens GCaMP was excited by a mercury lamp through a GFP mirror unit (U-MGFPHQ/XL Fluorescence images were acquired using an sCMOS camera (Zyla 4.2 sCMOS Andor Technology) controlled by NIS Elements BR (Nikon) A square region of the cortex (6 × 6 mm to 15 × 15 mm 512 × 512 or 256 × 256 pixels) was imaged at 5 Hz the animals were moved under a two-photon microscope (A1RMP Japan) equipped with a water immersion objective (16× or 25× with NA 0.8 or NA 1.1 Nikon) to perform two-photon calcium imaging GCaMP was excited at a 920-nm wavelength using a Ti:sapphire laser (Mai Tai HP DeepSee A square region of the cortex (800 μm × 800 μm in 512 × 512 pixels with a 16× objective for marmosets; 500 μm × 500 μm in 512 × 512 pixels with a 25× objective for mice) was imaged at 2 Hz The position of the FOV was selected from the functional map obtained using widefield imaging The spatial pattern of blood vessels on the cortical surface was used to guide the FOV The depth of the imaged plane was carefully adjusted manually between the scans Image planes from the same cortical location were separated by at least 30 μm in depth to avoid imaging the same neurons twice Visual stimuli were generated using custom-written programs in PsychoPy72 A 32-inch LCD monitor with a 60-Hz refresh rate (ME32B Samsung) was positioned 30 cm in front of the marmosets The stimulus screen spanned −35.6° to 35.6° horizontal and −50.7° to 50.7° vertical of the animal’s visual field a drifting square-wave grating [100% contrast; 0.5–1 cycle per degree (cpd); 2 Hz] tilted at one of four to eight orientations in equal steps moving in one of two directions orthogonal to the orientation was presented we presented a drifting square-wave grating [100% contrast; 0.5–1 cpd; 2 Hz] tilting at one of four to eight orientations in equal steps and moving in one of two directions orthogonal to the orientation [20 °/s] moving in one of eight or twelve directions in equal steps were used Each stimulus started with a blank period of uniform grey (4 s) followed by the same period of visual stimulation Each condition was repeated 20–100 times in pseudorandom orders In both the widefield and two-photon imaging experiments spontaneous activity was recorded separately from the visually evoked responses in the dedicated scans During scans for spontaneous activity recordings the LCD monitor used for visual stimulation was turned off we conducted a spontaneous activity scan either before or after the visual stimulus scans The interval between the two scans was no longer than 30 min All analyses were performed using custom-written programs in MATLAB (MathWorks small drifts between the imaging frames were realigned by maximizing the correlation between the images The relative change in fluorescence (ΔF/F) was computed using the following equation: ΔF/F = (F − F0)/F0 F0 is the average fluorescence during the pre-stimulus period (baseline) and F is the fluorescence during stimulus presentation and F is the fluorescence during spontaneous activity images or time courses were sorted by stimulus conditions and averaged across all repetitions single-condition maps to the tested orientation (or directions of motion) stimuli were obtained by calculating the relative change in fluorescence (ΔF/F) between the baseline (1 s before stimulus onset) and the stimulus period (4 s) Each map was high-pass filtered by subtracting the low spatial frequency background which was obtained by applying 2D median filters three times (kernel size: 0.45 mm by side) to the original map Direction preference maps (HLS maps) were obtained from single-condition maps hue (H) represents the preferred orientation or direction calculated by vector averaging saturation (S) represents the global measure of orientation or direction tuning which corresponds to 1 − CV (circular variance in orientation or direction preference) and lightness (L) represents the response to the best direction (ΔF/F) we first searched for a spontaneous PC that best correlated with the visually evoked activity We chose to analyse widefield imaging data covering V1 and V2 in the same FOV because these data allowed us to compare the two cortical areas without being affected by differences in animals and/or other experimental conditions Autocorrelation analysis was performed separately for V1 and V2 and the sizes of the two autocorrelation profiles were compared Because this analysis used widefield imaging data obtained from one FOV per animal we did not have sufficient data to perform statistical testing we set the number of pixels allocated to each cell to 100 for both mice and marmosets To compare visually evoked and spontaneous activity patterns we selected FOVs (1) with stable recordings of both visual stimulation scan and spontaneous activity scan and (2) with sufficiently large number of active cells (>100) we did the same calculation for the position-shuffled control The clustering index for the plane was defined as the value obtained for the position-shuffled control divided by the value obtained for the real data we set the number of cells and trials to be equal across all FOVs by randomly selecting 400 cells and 20 trials in each FOV neural activity was averaged across trials We treated each frame of the trial-averaged visual evoked response as an individual visual response pattern (frames corresponding to the stimulus-off periods were discarded) Depending on the number of orientations/directions tested the total number of trial-averaged visual responses for each set of stimuli ranged from 32 to 64 The frames in which visual stimuli were presented were then collected and denoted as trial-averaged visual responses producing a matrix \({M}_{{vis}}\) of trial-averaged visually evoked activity with dimension \({N}_{{neuron}}\,\times \,{N}_{{stim}}\) we used half of the trials to obtain \({M}_{{vis}}\) and spared the other half of the trials for later calculation of the projected variance of the visually evoked activity which is a matrix \({N}_{{neuron}}\,\times \,{N}_{{spont}-{frame}},\) was subjected to PCA and the first 50 PCs were retained (\({{PC}}_{1}^{{spont}},\,{{PC}}_{2}^{{spont}}\ldots \,{{PC}}_{50}^{{spont}}\)) \({N}_{{neuron}}\) was the same for the visually evoked activity and spontaneous activity The stimulus-only activity \({M}_{{vis}-{only}}\) was obtained by regressing out 50 spontaneous PCs from each column of the trial-averaged visual response each column \({e}_{i}\) in \({M}_{{vis}-{only}}\) is orthogonal to the spontaneous PCs The matrix of shared activities \({M}_{{shared}}\) was obtained by projecting each column \({v}_{i}\) of the trial-averaged visual responses \({M}_{{vis}}\) onto 50 spontaneous PCs each column \({w}_{i}\) of the shared activity \({M}_{{shared}}\) is contained in the space spanned by 50 spontaneous PCs: The matrix of spontaneous-only activity \({M}_{{spont}-{only}}\) was obtained by regressing out each column \({v}_{i}\) of the trial-averaged visual responses \({M}_{{vis}}\) from each column (i.e. frame) \({s}_{i}\) of spontaneous activity \({M}_{{spont}}\) each column \({u}_{i}\) of the spontaneous-only activity \({M}_{{spont}-{only}}\) was orthogonal to each column \({v}_{j}\) of the visually evoked activity \({M}_{{vis}}\): and the PCs of the shared space were obtained by finding a sequence of orthogonal directions \({a}_{i}\) that maximized the sum of squares of the trial averaged visual response \({M}_{{vis}}\): Note that the choice of 50 PCs at the initial step for constructing Shared Space could have resulted in underestimation of the number of remaining PCs in each subspace trial-to-trial variability of single-trial visually evoked responses in our data likely contained both visually related variability and spontaneous activity-related components We believe that some of the latter components were projected onto the sponta-only PC Regarding the non-zero projected variance on stim-only PCs in the spontaneous block we believe that this was because we projected out the top 50 PCs of spontaneous activity The residual PCs of spontaneous activity that were not used to define stim-only space could have contributed to the projection to the stim-only space Statistical tests were conducted using Statistics Toolbox in Matlab Independent group comparisons were performed using two-sample Kolmogorov-Smirnov tests No statistical methods were used to pre-determine sample sizes but our sample sizes were similar to those used in previous studies Allocation in the experimental groups was not randomized Data collection and analysis were not blinded to experimental conditions Further information on research design is available in the Nature Portfolio Reporting Summary linked to this article Minimum dataset that are necessary to interpret, verify and extend the research in the article are available from the corresponding authors. Example data can be downloaded in FigShare (doi:10.6084/m9.figshare.25448167). Source data are provided with this paper The codes used in this study are available from the corresponding authors. 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marmoset brain in stereotaxic coordinates Download references We thank members of the Ohki laboratory and Dr Watakabe for providing pAAV-Thy1S-tTA and pAAV-TRE-GCaMP6f; Drs Matsuizaki for technical advice; The Genetically-Encoded Neuronal Indicator and Effector (GENIE) Project for providing GCaMP6f/s This work was supported by Brain/MINDS and Brain/MINDS2.0 from AMED (14533320 Hirai and the Brain/MINDS AAV vector core); Institute for AI and Beyond (to K.O.); CREST-JST (JPMJCR22P1 to K.O.) Murakami); JSPS Research Fellowship for Young Scientist (20J12796 to T.H.) Brain/MINDS-beyond from AMED (JP20dm0307031 to T These authors contributed equally: Teppei Matsui International Research Center for Neurointelligence (WPI-IRCN) developed and provided GCaMP expression systems optimized for primates wrote the manuscript with contributions from all authors Nature Communications thanks Jorrit Montijn and the other reviewer(s) for their contribution to the peer review of this work Download citation DOI: https://doi.org/10.1038/s41467-024-54322-x Metrics details This paper presents a novel method for the measurement of nanometer-scale surfaces The proposed technique takes advantage of the spin hall effect of light (SHEL) which occurs as a sub-wavelength beam shift due to the spin-orbit interaction of light when it interacts with non-homogeneous optical media Governed by the conservation of total angular momentum the SHEL offers a sensitive approach to detecting the variations of optical properties at an interface “SHEL Ellipsometry” applies weak measurement principles to observe beam shifts which analyzes the polarization states of incident and reflected light a homogeneous sample with surface roughness less than a tenth of the wavelength can be modeled as a thin film characterized by an equivalent thickness and refractive index By measuring the transverse shifts of the reflected beam and using raster scanning SHEL Ellipsometry can map the two-dimensional surface roughness distribution showing significant potential for nanometer-scale surface measurement Despite the significant progress in fabrication technologies both in achieving angstrom-scale smoothness and complex nanostructures the development of nanoscale surface instruments has lagged Both techniques indirectly infer the surface and material properties of the illuminated area making them beneficial for fast large-scale measurements of nanoscale surfaces which are well-suited for industrial applications it has become easier to study the behavior and the application of this confined beam anomaly SHEL observation with weak measurement is realized by defining the polarization state of the incident and reflected beam in a way similar to ellipsometry measurement similar to scatterometry and traditional ellipsometry the optical properties of an observed surface can influence the measured transverse shift providing insights into the surface characteristics By incorporating SHEL with weak measurement and using the effective medium approximation (EMA) as a data analysis tool SHEL ellipsometry has the potential as an imaging tool that can give nanoscale surface information This paper offers a novel nanoscale surface characterization using the SHEL ellipsometry The measurement is done by measuring the SHEL shift of reflected light from the sample in an oblique incidence setup The SHEL shift is amplified by the weak measurement and recorded using a CCD camera A two-dimensional reconstruction of the surface was also obtained through raster scanning which completely avoids errors sourced from the retarder’s rotation or temperature dependence further offering good stability for long-term measurement two different interface models are introduced: based on the Fresnel model that returned the parameter as pseudo refractive index and based on the effective medium approximation to obtain equivalent effective thickness a comparison of pseudo refractive index and known refractive indices of several optics is presented as a result of static single-point measurements comparative scanning results are also presented to show the potential of SHEL ellipsometry as a novel nanoscale surface measurement Principle of the spin hall effect of light at an interface, a linearly polarized incident beam will be reflected with different direction of circularly polarized light and transversely shifted at a distance of \(\delta _r\). The 3D image was created using Microsoft PowerPoint version 16.93.2, Microsoft Corporation, (https://www.microsoft.com/powerpoint) which inherently carries information about the interface any change in the physical properties at the interface will be reflected as a change in the Fresnel reflection coefficients a complex weak value amplifies the weak interaction through the predetermined initial and final states the initial and final states correspond to the selection of the light polarization state upon incidence and reflection Figure 2 shows the schematic setup for SHEL ellipsometry based on SHEL observation using weak measurement Polarizer pairs realize the weak measurement through the definition of light polarization as the initial \(|i\rangle\) and final state \(|f\rangle.\) (inset) polarizer state corresponding to the weak measurement’s requirement the first-order amplified SHEL shift for a horizontally polarized incident is denoted by: where \(f_1\) and \(f_2\) correspond to the pair of lenses in Fig. 2 and \(w_{o}\) is the beam diameter at the laser outlet that relates to the propagation factor of the SHEL shift There are several approaches to improve the model inaccuracy in the vicinity of Brewster’s angle for the \(|H\rangle\) incident by performing Taylor expansion of the reflection coefficient or by improving the weak measurement model and the amplified SHEL shift for \(|H\rangle\) incident is denoted by: once the amplified SHEL shift is observed and the experimental parameters are known \(\rho\) is used to calculate the physical parameters The simplest model of an interface in optics is the air-glass interface where light propagates from air to a more condensed medium resulting in a change of refractive index along the propagation trajectory and \(\rho\) is defined using Snell’s Law and the Fresnel formulas as: The air-glass interface is assumed to be ideal, without any roughness, and \(\rho\) is simply defined as the ratio of Fresnel reflection coefficients p over s, referred here as the Fresnel model. Referring to the sample in Fig. 1 the refractive index of the air is \(n_0\) while the ideally smooth sample’s refractive index is \(n_2\) which is retrieved from SHEL measurements and is also addressed as the “pseudo” refractive index Numerical calculation of SHEL shift to incident angle on different refractive index (a) horizontally polarized incident beam and (b) vertically polarized incident beam Numerical calculation for the horizontally polarized incident on SiO\(_2\) flat windows with various levels of roughness d\(_{EMA}\) (colored lines) compared to Fresnel smooth surface (black line) (a) original SHEL shift and (b) amplified SHEL shift due to weak measurement based on Eq. 5 The experiment procedure is started by setting the sample stage and detection arm to form the desired incident angle the pair polarizer is set exactly perpendicular to each other or in a cross polarizer state without the small \(\varepsilon\) angle in P2 This state is essential to observe the splitting beam condition where two symmetrical intensities of SHEL beams appear The dark fringe between the two intensities is defined as the datum for measuring the SHEL shift the \(\varepsilon\) is added to the P2 to start the weak measurement both static measurement and scanning measurement can be performed The scanning measurement is performed by raster scanning through moving the \(xy\) translation stage Accuracy check by single point pseudo refractive index measurement of (a) samples consisting of flat windows of different material MgF\(_2\) (\(n = 1.37\)) (b) measurement result of horizontally polarized incident beam (c) measurement result of vertically polarized incident beam the results from the \(|H\rangle\) incident measurements are more accurate compared to the known values than those from the \(|V\rangle\) incident measurements The trend of the measurement results using \(|H\rangle\) also shows agreement with the actual value of the refractive index the \(|V\rangle\) incident with \(\varepsilon = 0.3^\circ\) and \(0.5^\circ\) shows a false trend and fails to retrieve the correct value of the refractive index The \(|V\rangle\) incident is more susceptible to error due to the small value of shift the shift difference due to varying medium properties will be even smaller Although the \(|V\rangle\) incident is inherently not limited by Brewster’s angle of the sample the tiny range of shift value in this proposed setup makes it a less favorable option This experiment demonstrates the potential of SHEL ellipsometry in retrieving the physical properties of samples as confirmed by comparing the pseudo-refractive index to the known refractive index of the samples it can be seen that as the post-selected angle increases the accuracy also improves and becomes closer to the ideal trend line A static measurement was carried out for varying incident angles to further understand the SHEL observation using weak measurement both from the perspective of the weak measurement model and from the measurement parameter The incident angle for the observation was varied by \(1^\circ\) increments from \(40^\circ\) to \(70^\circ\) Besides the space limitation due to the component size the focus of the measurement was on incident angles closer to Brewster’s angle a SiO\(_2\) optical flat with a refractive index of 1.45 (\(\theta _B= 55.5^\circ\)) was used The post-selected azimuth angles \(\varepsilon\) were \(0.5^\circ\) Measurement of amplified SHEL shift reflected from SiO\(_2\) (\(n = 1.45\)) compared to different model of weak measurement model red dash line represents first order weak measurement model solid blue line represents the second order weak measurement and black circle represents measured shift at each incident angle from 40\(^\circ\) to 70\(^\circ\) (a) azimuth angle 0.5\(^\circ\) the incident angle (\(\theta _i\)) and the post-selected azimuth angle (\(\varepsilon\)) One of the main proposals of this work is the reconstruction of the two-dimensional surface profile of the object under observation through raster scanning. As shown in Fig. 5 the sample stage is mounted on a motorized \(xy\)stage and data are acquired by recording the beam shift at every spot in the X and Y directions by moving the stage the scanning is conducted with overlapping steps smaller than the focused beam diameter The focused beam waist in this setup is 101 \(\upmu\)m and the scanning step for all measurements is 50 \(\upmu\)m in both the \(x\) and \(y\) directions After obtaining the data from all the spots along the raster scanning trajectories each data point is processed based on the SHEL ellipsometry model to retrieve the physical parameters followed by the reconstruction of the 2D distribution Scanning measurement of optics samples (a) MgF\(_2\) (\(n = 1.37\)) Scanning of different parts of optical flat (a) sample, (b) reconstruction of the central area, (c) reconstruction of edge area. Scanning of the optical flat four quadrant’s edge shows different levels of roughness on the outer edge circle detected by SHEL ellipsometry: (a) Result on 1\(^{st}\) area the polished surface and unpolished surface exhibit different roughness levels while the unpolished part has a higher Sa of 1.25 nm The AFM measurement confirmed the different roughness levels of the front and rear parts Comparison of polished and unpolished surface from AFM and SHEL ellipsometry (a) AFM of polished surface certain angle parameters in SHEL ellipsometry play crucial roles that impact amplification and measurement results yet compensating for angle error is also challenging Future studies should be made to assess the accuracy such as correlation analysis between AFM and SHEL ellipsometry across varying known surface roughness levels as well as utilizing an arbitrary incidence polarization angle for greater flexibility The demand for subnanometer areal surface inspection is rapidly increasing with the advancement of materials This proposed instrument offers a simple hardware setup without sample size constraints while enabling nanoscale surface characterization Although it does not provide direct measurements its efficiency competes with established existing methods such as AFM and SEM the inferred surface information can be flexibly modeled to suit different sample types allowing SHEL ellipsometry to analyze a broad range of materials This adaptability makes it valuable for diverse applications from precision glass polishing to metamaterial development This paper demonstrates the application of the SHEL ellipsometry for areal surface measurement the confirmation of the model with the experiment shows a good agreement the influence of the post-selected azimuth angle on the measurement result is evident from the retrieval of the pseudo-refractive index the scanning SHEL ellipsometry shows the reconstruction of the nanometer feature of observed samples Comparative measurement of known polished and unpolished surfaces validate SHEL ellipsometry as a novel roughness measurement technique with roughness equivalent thickness \(d_{EMA}\) representing different levels of roughness the roughness parameter can be expressed as either a pseudo refractive index or an equivalent roughness thickness depending on the sample’s known properties SHEL’s sensitivity to changes in the medium’s refractive index offers a significant advantage for nanoscale surface inspection with unlimited sample size and the ability to indirectly infer the properties of the illuminated area SHEL ellipsometry enables rapid assessment over large area measurements Validating the absolute measured value of surface roughness from SHEL ellipsometry presents a challenge much like other nanometer-scale instruments Future assessment methods could include correlation analysis or the development of calibration procedures and techniques The data sets generated during the current study are available from the corresponding authors on reasonable request Jiang, X. et al. 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Commun. 557, 130283. https://doi.org/10.1016/j.optcom.2024.130283 (2024) Download references This work was supported by Japan Society for the Promotion of Science (JSPS) KAKENHI Grant Numbers JP19H02154 and JP23K22769 conducted the investigations and prepared the original draft of the manuscript also contributed to supervision and secured funding for the study provided supervision throughout the project All authors discussed and approved the manuscript Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations Download citation DOI: https://doi.org/10.1038/s41598-025-95988-7 Metrics details High areal capacity and low-temperature ability are critical for lithium-ion batteries (LIBs) the practical operation is seriously impeded by the sluggish rates of mass and charge transfer the active electronic states of TiNb2O7 material is modulated by dopant and O-vacancies for enhanced low-temperature dynamics Femtosecond laser-based transient absorption spectroscopy is employed to depict carrier dynamics of TiNb2O7 which verifies the localized structure polarization accounting for reduced transport overpotential At high-mass loading of 10 mg cm−2 and −30 °C TNO-x@N microflowers exhibit stable cycling performance with 92.9% capacity retention over 250 cycles at 1 C (1.0-3.0 V a competitive areal capacity of 1.32 mAh cm−2 can be achieved Such a fundamental understanding of the intrinsic structure-function put forward a rational viewpoint for designing high-areal-capacity batteries in cold regions exploiting a practical route to enhance the charge-transfer kinetics of micron-sized TiNb2O7 for high-areal-capacity batteries under low temperatures is urgently desired the Li-storage behavior of the high-mass-loading TixNbyOz-based electrodes below −30 °C has not yet been reported; and also the correlation between the intrinsic electronic structure and low-temperature properties remains unclear The diagram reveal the different lithation kinetics mechanisms between TNO and TNO-x@N sluggish apparent Li+ diffusion rate and poor intrinsic electronic conductivity are obstacles for high-energy-density batteries in cold regions the synergistic effect of N-incorporation and O-vacancies can induce localized structure polarization and promoting Li+ adsorption at low-temperature conditions a Schematic diagram of the synthesis process of TNO-x@N d TEM image of TNO-x@N (the inset demonstrates the 3D image of TNO-x@N by Nano-CT technology) f Aberration-corrected STEM-HADDF image of the TNO-x@N g Oxygen defect analysis with ABF image of the TNO-x@N h Atomic-resolution EDS mappings of the TNO-x@N j Finite element simulation models of Li+ concentration of solid sphere (I) and microflowers (j) for different lithiation states at the current density of 5 C I Evolution of Li+ concentration in the solid sphere (k) and microflowers (l) TNO-x@N shows a distinct EPR signal peaks at g = 2.003 This result strongly proves that the thermal reduction process due to the ammonia annealing treatment leads to the appearance of bulk-phase oxygen vacancies in TNO-x@N in addition to surface vacancies enabling abundant Li+ storage sites and excellent transport ability in the TNO-x@N sample the bottom layer (near the current collector) of the solid sphere electrode is not lithiated fully the microflowers electrode allows for a uniform lithiation state These simulation results highlight the tremendous ion diffusion and storage capability in the compact nanostructure which is expected to achieve superior low-temperature performance b The dependent relationship of the formation energy of O-vacancy with concentration and position in TNO-x@N structure c The corresponding ELF plots of TNO-x@N and TNO e The electronic conductivities of TNO and TNO-x@N f PDOS values of the O p orbitals of TNO-x@N and TNO g Interfacial Li+ adsorption energy (the yellow i The migration energy barriers in the TNO the electrical conductivity of TNO-x@N is 1.47 × 10–3 S cm−1 nearly 5 orders of magnitude higher than that of TNO (4.29 × 10–8 S cm−1) As another key evaluation index reflecting the mass transport, Li+ transport pathways (Fig. 3h) and the corresponding diffusion energy barriers (Fig. 3i) are also calculated It can be seen that the relatively low diffusion barriers of TNO@N manifests the positive role of N-incorporation for Li+ migration Li+ diffusion energy barriers decrease with the increase in oxygen deficiency in Ti18Nb36N12O114-x further indicating the beneficial effects of rational O-vacancies in promoting diffusion kinetics confirm that the synergistic effect of N-incorporation and O-vacancies can induce localized structural polarization enhance Li+ adsorption and facilitate electron/ion mobility a Schematic illustration of principles for femtosecond transient absorption spectroscopy c The pseudo color TA spectra plots of TNO (b) and TNO-x@N (c) measured after excitation at 3.55 eV The black lines represent the position of positive and negative boundaries of the TA signal e TA spectra at different time delays between pump and probe pulse of TNO (d) and TNO-x@N (e) f Comparison of extracted dynamics at 625 nm probe and bi-exponential function fit curve g The energy-band structure diagram and recombination processes of excited-state carriers in TNO-x@N h Schematic diagram of polaron hopping between two identical metal ions with potential energy landscapes The dark and orange dashed curves indicate adiabatic surfaces of TNO and TNO-x@N Ea and Ea’ represent the polaron hopping activation energy of TNO and TNO-x@N i Schematic illustration of Li+ migration accompanies with polaron hopping process (the yellow a lower ∆Epol has a suppressive effect on polaron formation which is consistent with the increased trend in the time constant τ1 of the polaron formation process inferentially resulting in almost 5 orders of magnitude higher measured electrical conductivity of TNO-x@N we believe that electric delocalization plays an important effect on the formation and transport of polarons and is one of the main reasons that may contribute to the enhanced electric conductivity and reduced Li ion transport barrier a Cyclability and b rate capability of the three electrodes with the loading mass of about 1.5 mg cm-2 (1 C = 300 mA g−1) c Comparison of rate performance of TNO-x@N-based batteries with previously reported Nb-based electrodes d Long-term cycling stability of the TNO-x@N electrode with the mass loading of 1.5 mg cm−2 and 10 mg cm−2 after an activation process of 1 cycle at 0.2 C e Cross-sectional images of the electrodes with mass loading of 1.5 mg cm−2 and 10 mg cm−2 f Cyclability of the TNO-x@N electrode with the mass loading of 10 mg cm−2 operated at 1 C and −30 °C after an activation process of 3 cycles at 0.2 C g Temperature-dependent areal capacity and discharge capacity of the TNO-x@N electrode operated from 25 °C to −40 °C h Rate capability and i cyclability of TNO-x@N | |LiNi0.8Co0.1Mn0.1O2 pouch cell at 25 °C after an activation process of 3 cycles at 0.2 C (1 C = 250 mA g−1) j Infrared temperature images of TNO-x@N | |LiNi0.8Co0.1Mn0.1O2 pouch cell at 0.5 C and 1.0 C A high reversible capability of 184.4 mAh g−1 of TNO-x@N after 1000 cycles can be achieved much better than that of the TNO and solid TNO counterpart The TNO-x@N electrode exhibits the initial areal capacity of 3.14 mAh cm−2 and 2.36 mAh cm−2 at the current density of 0.1 C the areal capacity of 2.57 mAh cm−2 and 1.86 mAh cm−2 are obtained a Cross-section view slice of an original TNO-x@N electrode b Synchrotron X-ray tomography reconstruction with volume rendering shows the 3D microstructure of the active particles and pore connectivity network diagram (color indicates local pore center) d CV curve of half cells at various sweep rates of TNO-x@N at 25 °C e Capacitive contribution to the total capacity of TNO-x@N with the different mass loading g The calculated Li+ diffusion coefficients i Schematic illustration of how TNO-x@N realizes superwettability and solid TNO with the electrolyte at room temperature which is highly related with the electron transfer at the solid-liquid interface the slope angles of the low-frequency region are larger than 45o implying the existence of capacitive-like behavior during the Li-storage process Such high capacitive contribution are ascribed to the fast Li-storage at the high working current induced by the synergistic effect between N-incorporation and O-vacancies the nanosheet-assembled compact structure can provide available extra sites for interfacial storage which explains why TNO-x@N owns superior rate capability even at low temperatures and TNO-x@N with the electrolyte at room temperature are 24.3° further revealing that the TNO-x@N electrode is beneficial for the rapid migration of Li+ between the electrode and the electrolyte b In situ 2D contour of XRD plots of TNO-x@N (a) and TNO (b) d Selected 3D surface maps and corresponding contour maps TNO-x@N (c) and TNO (d) f Lattice-constant variations and corresponding discharge/charge curves of TNO-x@N (e) and TNO (f) g Nb 3d XPS spectra recorded at different potentials h–k Ex situ TEM and HRTEM images of the TNO-x@N at the discharge to 1.0 V (h l Elemental mapping images of the TNO-x@N at the discharged state of 1.0 V which is attributed to the fact that anion engineering can effectively increase the interlayer spacings thereby alleviating the repetitive strains induced by the volumetric expansion and contraction during lithiation and delithiation a charge-transfer-enhanced TiNb2O7-x@N electrode with a unique delocalized electronic structure has been constructed for high-areal-capacity batteries at low temperatures Time-resolved optical spectroscopy reveals that the heterogeneous adjustment of the electronic structure of TiNb2O7 induces an impurity energy band at the Fermi energy level lowering polaron hopping activation energy and increasing the free carrier and polaron concentration for improved electronic conductivity The results are in strong agreement with the theoretical calculations Such regulation provides an inclination for Li+ adsorption and decreases the energy barriers for ion diffusion which in turn accelerates electrochemical reaction kinetics the TNO-x@N electrode exhibits large reversible capacity It can even deliver an areal capacity of 1.32 mAh cm−2 at −40 °C a dramatically decreased lattice volume expansion of TNO-x@N electrode is achieved during the lithiated/delithiated process This work sheds light on the design concept of localized structure polarization inspiring a pathway of structural engineering strategy toward practical applications of low-temperature batteries 3 mmol niobium pentachloride and 18 mmol oxalic acid were dissolved in 50 mL distilled water and labeled as Solution A 1.5 mmol tetrabutyl titanate and 6 mmol oxalic acid were further dispersed in 20 mL anhydrous ethanol and labeled as Solution B Solution A was dropped into Solution B to form Solution C 12 mmol ammonium fluoride was added into Solution C by stirring for 100 min to a transparent solution Solution C was transferred into a 100 mL Teflon-lined autoclave and heated at 180 °C for 12 h the product was washed repeatedly with alcohol before drying it at 80 °C for 10 h to achieve TNO precursor The TNO precursor was annealed at 750 °C for 4 h with a heating rate of 5 °C min-1 in a tube furnace to obtain TNO composite the obtained TNO powder was heated under a mixed Ar/NH3 atmosphere to 700 °C for 1 h to obtain nitrided TNO microflowers (abbreviated as TNO-x@N) The solid TNO material was obtained by homogeneous mixing of Nb2O5 and TiO2 with a certain ratio in an ethanol solution followed by heating in a muffle furnace at 1225 °C for 20 h Crystal structures of samples were investigated by X-ray diffraction (XRD Bruker D8 Advance) and Raman spectra (Jobin-Yvon Lab RAM HR-800) Surface chemistry was analyzed with X-ray photoelectron spectra using the PHI 5700-ECSA system Helios Nanolab 600i) and transmission electron microscopy (TEM FEI Talos 200 S) were employed to determine the structure and morphologies of the samples The high-angle annular-dark-field and annular-bright-field images were performed with a spherical-aberration-corrected scanning transmission electron microscope (Titan Cubed Themis G2 300) Contact angles were acquired on a Cam-plus Micro meter using the sessile-drop technique and polyvinylidene fluoride (PVDF) was 8:1:1 to fabricate the regular working electrode slurry which was coated on Cu foils and dried in a vacuum at 100 °C for 10 h The average loading of active materials in the regular anode was about 1.5 mg cm-2 and the 1C-rate was defined as 300 mA g-1 at the voltage range of 1.0-3.0 V The electrolyte was a mixture of ethyl carbonate diethyl carbonate and dimethyl carbonate with a volume ratio of 1:1:1 containing 1 mol L−1 LiPF6 The diameter of the regular electrode was 14 mm and the diameter of the separator was 16.5 mm The separator of all half-cells and pouch cells is the Celgard 2500 polypropylene membrane dimensions and capacity of Li foils were 15.6 mm and PVDF were homogeneously mixed with a mass ratio of 9:0.5:0.5 The diameter of the high-loading electrode was 12 or 10 mm the 1C-rate was defined as 250 mA g-1 at the voltage range of 1.0–3.0 V Lithium metal and LiNi0.8Co0.1Mn0.1O2 were used as electrode materials to assemble half-cells and pouch cell the slurries consisting of LiNi0.8Co0.1Mn0.1O2 as the active materials Kejten black & carbon nanotube as the conducting agent and polyvinylidene fluoride (PVDF) binder in a weight ratio of 95.2:3:1.8 were prepared The cathode electrode had a mass loading of approximately 6.4 mg cm-2 and a compaction density of 3.45 g cm-3 the pastes consisting of TNO-x@N as the active materials and PVDF binder in a weight ratio of 92:5:3 were fabricated The anode electrode had a mass loading of approximately 4.8 mg cm-2 and a compaction density of 2.30 g cm-3 The dimensions of the electrode are 4.3 × 4.2 cm The N/P ratio of the pouch cell was set to 1.0 the average mass loading of the single-sided anode and cathode electrodes was about 15.4 and 16.1 mg cm-2 The dimensions of the electrode are 4.6 × 8.0 cm and the cathode and anode electrodes were assembled by stacking the pieces The 1C-rate is defined as 3.5 A at the voltage range of 1.0–3.0 V The mass energy density of TNO-x@N-based pouch cell can be quantified by the equation of mass energy density = cell capacity × average voltage/electrode weight The volumetric energy density of TNO-x@N-based pouch cell can be calculated by the equation of volumetric energy density = cell capacity × average voltage/electrode (thickness × width × length) Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) were performed on a CHI760 electrochemical workstation The galvanostatic charge/discharge tests were conducted on the Neware-CT3008 system According to Fick’s second law of diffusion TNO and solid TNO electrodes can be computed by: ∆ES and ∆Eτ stand for the change in the steady-state potential and the change in potential after the pulse The implement of electrochemical simulation was carried out on the surface of the solid sphere and microflowers electrode using the cubic current distribution physical field interface in the COMSOL Multiphsics software The model is based on the calculation of currents in the electrolyte and electrodes using the “cubic current distribution” interface the electrolyte current is resolved according to Ohm’s law and the other is set to the battery potential to meet the total current condition the electric field follows the continuity equation using the current density: where \(i\) is the current density vector; zi is the ion charge; mi is the mobility and ci represents the concentration of the ion it is consistent with the conservation of current density Expressions of the Butler-Volmer form are utilized in the simulations to describe the electrode kinetics occurring at the electrode surface inserted in the electrolyte and the exchange current density for the oxidation reaction is considered to be concentration-dependent The electrode surface current density is referred to as the Butler-Volmer equation: The initial value of the electrolyte potential is set to be comparable to the potential of the cell at an open circuit (the open circuit voltage) ϕl is the electrolyte potential and Eeq is the equilibrium potential The transport of dissolved Li+ in the electrolyte and electrode during charging and discharging is modeled by transient simulations of the “rare-mass transfer” interface which assumes that the transport of ions can be described by diffusion according to Fick’s law mass transfer induced by the diffusion and migration is considered in which \(c\) represents the concentration of the ions \({{\mbox{F}}}\) and ϕl stand for the Faraday’s constant and ionic potential The ionic concentration in the electrode material meets the depletion reaction process which is modeled using the PDE module of the software: where ks is the rate of consumption reaction we set the bottom reference potential as zero potential and the top as the average current density boundary 2.5 mA/cm2 the conductivity of the electrolyte is set as 4.5 S/m The diffusion coefficient of the ions as 5 × 10-10 m2/s and the environmental concentration of the Li ions boundary as 1 mol/L The femtosecond transient absorption (fs-TA) setup is based on a regenerative amplified Ti: sapphire laser system from a Coherent and Helios pump-probe system (Ultrafast Systems) The regenerative amplified Ti: sapphire laser system (Legend Elite-1K-HE and 1 kHz) was seeded with a mode-locked Ti: sapphire laser system (Vitara) and pumped with a Nd: YLF laser (Evolution 30) the 800 nm output pulse from the regenerative amplifier was split into two parts with a 50% beam splitter The transmitted part was used to pump a TOPAS Optical Parametric Amplifier (OPA) which generates a wavelength-tunable laser pulse of 350 nm as a pump beam and is chopped by a mechanical chopper operating at a frequency of 500 Hz Another reflected part of the fundamental beam was introduced into the TA spectrometer to generate the probe light After passing through a motorized optical delay line the fundamental beam was focused on a sapphire crystal which was used to generate the white-light continuum (WLC) probe pulses with wavelengths of 430–820 nm The optical path difference between the pump light and the probe light which is controlled by the motorized optical delay line was used to monitor the transient states at different pump-probe delays A reference beam was split from the WLC to correct the pulse-to-pulse fluctuation of the WLC The pump was spatially and temporally overlapped with the probe beam on the sample two samples of TNO and TNO-x@N were prepared by following steps TNO and TNO-x@N were added to ethanol in the weight ratio of 10:1 (ethanol: TNO/TNO-x@N) through ultrasonic dispersion in a water bath for 2 hour to obtain the TNO and TNO-x@N mixture suspension the TNO and TNO-x@N films were deposited on cleaned SiO2 substrates by spin coating at 1200 rpm for 30 s they were sealed with thin SiO2 substrates and epoxy resin to isolate the air All these steps were conducted in a nitrogen environment at room temperature in situ cells were assembled in glovebox with Li metal as counter electrode and 1 mol L−1 LiPF6 in a mixture of the ethyl carbonate diethyl carbonate and dimethyl carbonate (1:1:1 volume ratio) as the electrolyte Each XRD curve is collected with a time frame of around 15 min and the total time for the first cycle of charge and discharge at the current density of 0.25 C is approximately 7.2 h the coin cells were transferred to a glove box after a certain number of cycles and dismantled to remove the test electrodes The removed electrodes were soaked in dimethyl carbonate solution for 12 h and dried and sealed in a glass bottle for subsequent testing This process always avoids contact with air The Vienna Ab Initio Simulation Package (VASP) for all the spin-polarized DFT calculations within the generalized gradient approximation (GGA) using the PBE functional formulation was implemented Projected augmented wave (PAW) pseudopotentials were employed to describe the electron-ion interaction The valence electronic states were expanded in plane wave basis sets with the energy cutoff of 450 eV The electronic energy is considered self-consistent when the energy change is smaller than 10−6 eV while a force change smaller than 0.03 eV/Å is used to determine the convergence of the geometry optimization Oxygen vacancy formation and lithium-ion migration were calculated using the TiNb2O7 supercell bulk model of 1 × 3 × 1 while the adsorption/desorption of EC-Li was calculated using the TiNb2O7 (001) slab model with a p(1 × 3) supercell The climbing-image nudged elastic band (CI-NEB) method was applied to obtain the diffusion barriers The data that support the plots within this paper and other findings of this study are available from the corresponding author upon request. Source data are provided in this paper Three-dimensional holey-graphene/niobia composite architectures for ultrahigh-rate energy storage Constructing a highly efficient aligned conductive network to facilitate depolarized high-areal-capacity electrodes in Li-ion batteries Coupling of multiscale imaging analysis and computational modeling for understanding thick cathode degradation mechanisms and high-areal-capacity battery electrodes enabled by through-thickness aligned carbon fiber framework From fundamental understanding to engineering design of high-performance thick electrodes for scalable energy-storage systems Few-layer bismuthene with anisotropic expansion for high-areal-capacity sodium-ion batteries 40 years of low-temperature electrolytes for rechargeable 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for fast charging lithium batteries with graphite anode Layering charged polymers enable highly integrated high-capacity battery anodes Efficient implementation of kilogram-scale high-capacity and long-life Si-C/TiO2 anodes An ion-conductive grafted polymeric binder with practical loading for silicon anode with high interfacial stability in lithium-ion batteries Coordinatively-intertwined dual anionic polysaccharides as binder with 3D network conducive for stable SEI formation in advanced silicon-based anodes Enhanced ion conductivity in conducting polymer binder for high-performance silicon anodes in advanced lithium-ion batteries Download references This work was supported by the National Key Research and Development Program of China (2022YFE0138900 the National Natural Science Foundation of China (Grant No the Shanghai Aerospace Science and Technology Innovation Fund (No the Young Elite Scientist Sponsorship Program by CAST (No and the Fundamental Research Funds for the Central Universities (Grant No Biao Deng of the beamline BL13W1 and BL18B at Shanghai Synchrotron Radiation Facility (SSRF) for SR-CT measurements These authors contributed equally: Yan Zhang State Key Laboratory of Space Power-Sources conceived the project and designed the experiments contributed to part of the preparation and characterization of the material and the electrode wrote the manuscript with support from all authors Nature Communications thanks the anonymous reviewers for their contribution to the peer review of this work Download citation DOI: https://doi.org/10.1038/s41467-024-50455-1 Metrics details Empathy enables understanding and sharing of others’ feelings Human neuroimaging studies have identified critical brain regions supporting empathy for pain the precise spatio-temporal profiles of empathic neural responses and inter-regional communications remain elusive we investigated electrophysiological signatures of vicarious pain perception Others’ pain perception induced early increases in high-gamma activity in IFG but decreased beta power in AI and amygdala Vicarious pain perception also altered the beta-band-coordinated coupling between ACC as well as increased modulation of IFG high-gamma amplitudes by beta phases of amygdala/AI/ACC We identified a necessary combination of neural features for decoding vicarious pain perception These spatio-temporally specific regional activities and inter-regional interactions within the empathy network suggest a neurodynamic model of human pain empathy it is crucial to assess the spatio-temporal dynamics of neural oscillations and inter-regional communication modes in empathy-related regions to understand how functionally diverse processes dynamically merge into empathic responses towards others’ feelings (i) the temporal order and spectral patterns of neural activity in different empathy-related brain regions (ii) the rapid functional interactions between different brain regions remains elusive (iii) it is also unclear whether and how vicarious pain perception can be decoded from multiple features of the neural activity and inter-regional communications The current study aimed to address these questions by recording intracranial electroencephalography (iEEG) signals during the perception of others’ pain This helps us understand how the brain gives rise to empathic responses to vicarious pain reveal the dynamic organization of the empathy network and construct a neurodynamic model of empathy these studies focused exclusively on a single empathy-related region it remains elusive how the anatomically distributed and functionally distinct neural activity within the empathy network are temporally and spatially organized during perception of others’ pain The current study sought to reveal the region-specific spectral patterns and the temporal order of empathic neural responses by recording neuronal population activities in four key empathy-related nodes—the ACC and IFG—in 22 epilepsy patients while they viewed pictures depicting painful stimulation applied to others’ hands Thus we examined both low-frequency coupling and phase-amplitude coupling to assess how the ACC and IFG interacted when observing other’s suffering Leveraging the strengths of iEEG and advanced analysis of neurophysiological signals we provided a spectral-temporal-spatial map of neuronal population activity and inter-regional interaction dynamics that subserved empathic pain experience in humans In an effort to delineate the specific contributions of these spectral-temporal-spatial specific patterns to vicarious pain perception and identify important neural features we further investigated how these neural features jointly contributed to the perception of others’ pain to assess the associations between empathic responses and critical neural features within the pain empathy network we tested how these critical neural features were linked to empathy-related behavioral measures including the strength of overall empathic responses and empathy-related subprocesses (i.e. evaluation of perceived pain intensity and one’s own unpleasantness) during perception of other’s pain This investigation was potentially important for empathy research as it would help assess the importance of different types of neural features for vicarious pain perception and identify tailored targets for interventions of empathy-related deficits providing evidence for empathic responses to other’s pain in our patients patient and healthy individuals showed similar response patterns in differentiating painful and non-painful stimuli patients’ empathic responses to vicarious pain were comparable with those of healthy individuals showing evidence for early and sustained involvement of high-gamma IFG activity in the processing of vicarious pain we calculated power correlations in the overlapping frequency bands of the respective intra-regional power effects for each pair of regions (alpha and beta bands for ACC-AI; beta band for ACC-amygdala and AI-amygdala) power correlation was computed as the Fisher-z-transformed correlation coefficient across the stimulus-presentation window (i.e. We then compared the power correlation coefficients between painful and non-painful conditions (two-tailed paired t-tests for each frequency using cluster-based permutation tests to correct for multiple comparisons) from AI to amygdala and from the amygdala to AI) across the stimulus-presentation time window We averaged TE values across frequency ranges of the corresponding power correlation effect and submitted them to repeated-measures analyses of variance (ANOVAs) with Pain (painful vs non-painful stimuli) and Direction as within-subjects factors For the interactions between the ACC and amygdala at 25–30 Hz no significant results were found for the main effect of pain or the interaction effect (Main effect of pain: F1 We thus tested whether the phase of low-frequency oscillations in the AI/ACC/amygdala modulated high-gamma amplitudes of the IFG during empathic responses by performing inter-regional phase-amplitude coupling (PAC) analysis The phase and amplitude time series were obtained for frequencies in the frequency bands of the respective intra-regional power effect (phase frequency bands: alpha/beta bands in the ACC and beta band in the amygdala; amplitude frequency: 70–150 Hz in the IFG) PAC values were indexed by circular-linear correlation coefficients between the phase time series and the amplitude time series We then compared the Fisher-z-transformed PAC values across channel pairs between the painful and non-painful conditions (two-tailed paired t-tests for each frequency pair We tested how the neural activity and neural synchronization in the ACC and IFG contributed to the detection of other’s pain we employed a support vector machine to construct a decoder to discriminate perception of painful and non-painful stimuli from power we split our dataset into two parts at the channel or channel-pair levels (detailed in Methods) One feature-selection dataset where we performed time-frequency decomposition of iEEG signals for each region and calculated inter-regional correlations of low-frequency power and PAC value for channel pairs was used to select relevant features (see Methods) The other decoding dataset was used to construct and validate the classification model As a validity check of our classification model before further analyses we assessed its classification performance and found that our classification model significantly differentiated labels of painful and non-painful stimuli (classification accuracy = 76.28% indicating that this eight-feature combination is necessary for discriminating between painful and non-painful stimuli the removal of this eight-feature combination led to significantly lower decoding accuracy compared to randomly removing an equal number of features (p < 0.001) further supporting the importance of this eight-feature combination in vicarious pain perception This suggested that stronger empathic responses were linked to greater suppression of ACC alpha oscillations and AI low-frequency oscillations These findings further suggested that suppressed ACC alpha power and AI low-frequency power not only facilitated qualitative differentiation between others’ pain and non-pain (signaling the presence of other’s pain) but also quantitatively tracked the strength of empathic responses These results showed that stronger suppression of AI low-frequency power was related to higher intensity of perceived pain in others but a lower level of self-related unpleasantness the observed neural effects cannot be attributed to potential differences in arousal levels between painful and non-painful stimuli Our iEEG results revealed the precise spectro-temporal characteristics of neural responses in the key regions of the empathy network (i.e. and IFG) and the electrophysiological basis of the inter-regional communications among these regions during perception of others’ pain The oscillatory patterns and inter-regional functional interactions provide insights into our understanding of how different processes dynamically coordinate and merge into empathy for pain It would be valuable for future research to directly test this possibility it remains unclear how rapid communications between empathy-relevant brain regions support empathic responses in humans Our iEEG results provided electrophysiological evidence for the engagement of these two circuits in human empathy suggesting the ACC/AI-amygdala circuit as an evolutionarily conserved mechanism of empathy we identified a different mode of inter-regional communication related to empathy — cross-frequency coupling between high-gamma IFG and beta ACC/AI/amygdala — which points towards new directions for future investigations into empathy-related circuits The current study provided evidence for both increased functional interactions (e.g. enhanced coupling between ACC beta phase and IFG gamma amplitude) and decreased inter-regional communications (e.g. attenuated beta coupling between ACC and AI) within the empathy network These patterns highlighted rapid information flow among different brain regions to coordinate diverse processes of empathy the brain needs to not only enhance functional interactions between specific empathy-related regions (e.g. potentially facilitating their coordination and information integration but also appropriately suppress certain inter-regional communications in order to reduce mutual distractions and increase functional specialization of relevant brain regions (e.g. These findings on empathy-related inter-regional communication aid in understanding how the brain generates empathic responses towards others’ pain The behavioral and neural data in the current work were collected from epilepsy patients the disease or treatments might impact our findings to a minimum extent Patients in our study indeed perceived others in stronger pain and reported stronger empathic responses when seeing others in painful (relative to non-painful) situations patients and healthy controls showed comparable behavioral performances during judgments of others’ pain and subjective ratings of each stimulus patients’ neural responses were predictive of the strength of empathic responses as well as their own ratings of perceived pain intensity and unpleasant feelings of vicarious pain These results provide consistent evidence for the engagement of empathic response to painful stimuli in patients and the behavioral and neural patterns observed here reflect response profiles of perceived pain in others It would be interesting for future studies with larger sample size and trial number to further investigate if and how the experimental task modulates spectral patterns within different subregions of the insula as well as other empathy-related regions during processing others’ pain our iEEG results revealed frequency-specific patterns in the key nodes of the empathy network and identified two inter-regional communication modes as crucial neurophysiological mechanisms underlying empathy for pain our findings of the beta-band-coordinated synchronization between the AI as well as the cross-frequency coupling between the AI/ACC/amygdala (low-frequency) and IFG (high-gamma) provide insights into how functionally diverse and spatially distributed brain regions communicate and coordinate when perceiving others in pain These findings contribute to a sophisticated understanding of the neural dynamics of empathy which may help with the prediction of empathy-motivated prosocial behaviors and the development of therapeutic interventions targeting empathy-related deficits commonly observed across various neuropsychiatric disorders electrode localizations were exclusively determined by clinical needs We prioritized and maintained the integrity of clinical care during conducting the current study All patients provided informed consent after the experimental procedure had been fully explained and were acknowledged their right to withdraw at any time during the study The experimental design and procedures adhered to the standards set by the Declaration of Helsinki and were approved by the local Institutional Review Board of each hospital where the patients were tested (i.e. the Chinese PLA General Hospital: S2021-394-02 Beijing Xuanwu Hospital: ClinRes No.2022018 and Beijing Tiantan Hospital: KY 2020-080-02) Data were recorded from 29 epilepsy patients who were implanted with intracranial depth electrodes and were undergoing intracranial EEG monitoring to localize the seizure onset zone for potential surgical resection All participants recruited in the current study had no history of psychiatric disorders Patients did not take pain medication several hours prior to the iEEG recording of the pain judgment task and were not experiencing any physical pain during the iEEG recording The patient selection was based on two inclusion criteria: (i) having electrodes in the ACC or IFG contralateral to or outside of the epileptogenic zone; and (ii) achieving a response accuracy above 50% in the pain judgment task one patient was excluded due to a low response accuracy (45%) in the pain judgment task and six patients were excluded because no electrodes were implanted in the regions of interest The remaining 22 patients were included in the behavioral and neural analysis of the pain judgment task (13 males alpha error = 5%) confirmed that we had sufficient power (86.94%) to detect medium effect sizes (d = 0.5) even with the minimum number of channels (n = 40) We employed stringent thresholds and the main findings are highly significant statistically and survived correction for multiple comparisons and color of the painful and non-painful stimuli were matched Each stimulus was presented on a gray background of a 21.5-inch color monitor during iEEG recording subtending a visual angle of 11.33° × 8.51° at a viewing distance of 80 cm Participants were then presented with a painful or non-painful picture with a duration of 500 ms and were instructed to understand and empathize with the emotional states of the person depicted in the pictures To motivate and monitor engagement in the task participants were asked to indicate whether the person in each picture experienced pain or not (as specified by Chinese instruction: “请您判断图片中的人是否感到疼痛”) by pressing the left (index finger) or right (middle finger) button using their dominant hands after the picture disappeared Participants made these responses on a self-paced basis and were encouraged to respond as accurately as possible the picture viewing phase and response phase were separated in order to isolate vicarious pain perception from any potential biasing effects of motor responses on neural responses to others’ pain painful and non-painful pictures were presented once in a random order These results suggested that the observed neural effects were not due to potential differences in arousal levels between painful and non-painful stimuli To demonstrate that patients were not impaired in their responses to vicarious pain and showed empathy-related behavioral patterns similar to that in healthy controls we recruited a healthy participant sample whose gender and age distributions were comparable to those of the patient sample (n = 22; 9 males age = 23.18 ± 2.38 years old) (age: t42 = −0.81 two-sided two-sample t-test; gender: χ2(1) = 0.82 two-sided Pearson’s Chi-square test of independence) Healthy participants were asked to complete the same pain judgment tasks and provide subjective ratings of the strength of empathic response and their own unpleasantness for each stimulus We then compared subjective ratings between painful and non-painful stimuli to check empathic responses to others’ pain in our patients (two-tailed paired t-tests) We then examined whether patients and healthy participants showed different responses and subjective feelings to vicarious pain Data were averaged across trials in each condition for the response accuracy and time in the pain judgment task and subjective ratings we examined group differences between patients and healthy participants by constructing linear mixed-effect models with participants as a random effect to control for individual variations the aggregated data were then entered into separate linear mixed-effect models to compare between two groups which included fixed-effects of pain (painful vs We then performed F-tests on the fixed effects estimates (two-tailed) The null distribution was generated by randomly flipping the sign of Fisher-z-transformed patient-normative correlations or healthy-normative correlations we examined the difference between the patient-normative and healthy-normative correlation coefficients (two-tailed permutation tests) by creating a null distribution via randomly shuffling membership between patient group and the healthy participant group iEEG data were recorded using amplifiers from a Nicolet electroencephalogram system (256 channel amplifier the Chinese PLA General Hospital) or a Nihon Koheden system (256 channel amplifier or a Micromed system (128 channel amplifier Each electrode was 0.8 mm in diameter and contained 5 to 18 contact leads 2 mm wide and 1.5 mm apart iEEG data for the pain judgment task were collected when no subclinical or clinical seizures occurred during or immediately before the task All the remaining channels were also visually inspected to ensure that all bad channels had been removed we visually screened all channels for epileptic charges and removed those with too many remaining artifacts All visual inspections were performed while blinded to the experimental conditions and then conducted paired-t tests to examine the conditional power differences among the random channels This procedure was repeated for 1000 times resulting in 1000 t values to construct the null distribution The observed conditional power difference was then compared with this null distribution We found that the observed conditional effects of all these clusters were significantly stronger than those calculated based on random channels (ACC alpha cluster: p = 0.011 ACC beta cluster: p < 0.001; AI low-frequency cluster: p < 0.001; amygdala beta cluster: p < 0.001; IFG high-gamma cluster: p < 0.001) we investigated the power correlations between each region pair of the AI and amygdala in overlapping frequency bands that significantly differentiated between painful and non-painful stimuli (including the alpha and beta bands for ACC-AI and the beta band for ACC-amygdala and AI-amygdala) To eliminate the potential influence of individual differences we only considered pairs of channels within each participant (i.e. the two channels of each pair from the same participant) and included participants with at least one channel pair the inter-regional PAC values were computed as the circular-linear correlation coefficient between the phase time series of the amygdala/AI/ACC and the amplitude time series of the IFG (across the post-stimulus time window 0–500 ms) and Fisher-z-transformed and averaged across all epochs in each condition we performed feature selection and model construction using separate datasets we randomly split our data into two independent sub-datasets at the channel (or channel pair) level with 70% of the data as the feature-selection dataset to identify informative features and the remaining 30% of the data as the decoding dataset to construct the classification model to decode stimulus types we linearly scaled each feature to the range [0 the classification performance of the SVM classifier was evaluated by a five-fold cross-validation procedure We randomly divided all trials into 5 folds the classifier was trained on the remaining 4 folds and then tested on the held-out testing fold The decoding accuracy of the confusion matrix (i.e. (true positive + true negative)/total observation) was calculated based on the average of five iterations we calculated the average accuracy across all iterations and resamples as a result We assessed the statistical significance of the decoding accuracy using a permutation test104 we randomly shuffled the class labels and the entire decoding procedure detailed above was repeated we obtained the null distribution of decoding accuracy which can well-capture the variability of decoding accuracy corresponding to the current sample size We controlled for the influence of limited sample size on the variations of decoding accuracy by comparing the true decoding accuracy with this null distribution (one-tailed the operations to respectively remove each feature from the model resembled the scenarios when a specific feature was disrupted As none of the neural features can individually determine the success of the decoding we further searched for feature combinations which were necessary for successful decoding We performed stepwise classification by removing features sequentially and evaluating the classification performance of the remaining features until the decoding accuracy was reduced to the chance level Those removed features consisted of a necessary feature combination for successful decoding To lend further evidence to strengthen the importance of the detected feature combination we took into account the influence of feature numbers and compared the decoding accuracy when removing this feature combination to that when randomly removing an equal number of features (random removing for 1000 times For each feature encoding empathic strength we conducted similar analyses to explore whether and how this feature was associated with perceived pain intensity in others and one’s own unpleasantness when witnessing others in pain All the independent and dependent variables were standardized before entering in the model and all the two-tailed p-thresholds were adjusted via FDR-correction based on the number of statistical tests Given the limited number of patients who completed post-iEEG ratings we applied a less stringent threshold of FDR corrected p < 0.05 for all these analyses to reduce risk of false negatives we also checked the associations between the neural features encoding empathy strength and arousal ratings to further demonstrate their specificity in the encoding of empathy-related behavioral responses Further information on research design is available in the Nature Portfolio Reporting Summary linked to this article The raw and preprocessed iEEG data generated in this study have been deposited in a local database. The iEEG data are available under restricted access as they contain personally identifiable information and patients have not consented to data distribution. Access can be obtained from the corresponding author upon request. Source data are provided with this paper The code to perform wavelet transform and compute power correlations and phase-amplitude coupling is publicly available (https://github.com/Huixin-Tan/iEEG_empathy) The access of other codes is available from the corresponding author upon request Neural responses to ingroup and outgroup members’ suffering predict individual differences in costly helping Empathy as a driver of prosocial behaviour: highly conserved neurobehavioural mechanisms across species Stimulating the brain to study social interactions and empathy The functional architecture of human empathy Dynamic construction of the neural networks underpinning empathy for pain Is empathy for pain unique in its neural correlates A meta-analysis of neuroimaging studies of empathy Neural mechanisms necessary for empathy-related phenomena across species Functional dissociation of the frontoinsular and anterior cingulate 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of cortical networks encode spontaneous behavior Download references Yuan for their assistance in data collection This work was supported by the National Natural Science Foundation of China (Projects 32125019 to Y.M.; 32230043 to S.H.); STI 2030—Major Projects 2022ZD0211000 to Y.M.; the Fundamental Research Funds for the Central Universities (2233300002 to Y.M.); and the start-up funding from the State Key Laboratory of Cognitive Neuroscience and Learning State Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal University Beijing Key Laboratory of Brain Imaging and Connectomics School of Psychological and Cognitive Sciences PKU-IDG/McGovern Institute for Brain Research conceived of the project and designed the experiments; X.Z. and F.M performed the experiments and collected data; H.T. analyzed the data under the supervision of Y.M.; H.T All authors approved the final version of the manuscript for submission Nature Communications thanks Efe Soyman and the other 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Volume 8 - 2020 | https://doi.org/10.3389/feart.2020.607049 Geomagnetic jerks are sudden changes in the geomagnetic field secular variation related to changes in outer core flow patterns Finding geophysical phenomena related to geomagnetic jerks provides a vital contribution to better understand the geomagnetic field behavior we link the geomagnetic jerks occurrence with one of the most relevant features of the geomagnetic field nowadays which is due to the presence of reversed flux patches (RFPs) at the Core-Mantle Boundary (CMB) Our results show that minima of acceleration of the areal extent of SAA calculated using the CHAOS-7 model (CHAOS-7.2 release) coincide with the occurrence of geomagnetic jerks for the last 2 decades a new pulse in the secular acceleration of the radial component of the geomagnetic field has been observed at the CMB with a maximum in 2016.2 and a minimum in 2017.5 along with the minimum observed in 2017.8 in the acceleration of the areal extent of SAA We have also analyzed the acceleration of the areal extent of South American and African RFPs at the CMB related to the presence of the SAA at surface and have registered minima in the same periods when they are observed in the SAA at surface This reinforces the link found and would indicate that physical processes that produce the RFPs contribute to the core dynamics at the origin of jerks The secular variation of the core geomagnetic field is generally characterized by smooth variations in time. However, since the end of the 1970s with the works of Courtillot et al. (1978) and Malin et al. (1983), the geomagnetic community has been interested in the occurrence of abrupt changes, not globally simultaneous (Brown et al., 2013) observed in the trend of the first derivative of the field elements They used between six and four geomagnetic observatories to estimate the occurrence times of the most recent geomagnetic jerks they found alternated sign of the acceleration at some regions that when associated with large spatial scale structures could cause geomagnetic jerks at the Earth’s surface By using global geomagnetic field models based on paleomagnetic data, Terra-Nova et al. (2016) observed that the reversed flux patches (RFPs) present at the CMB regions with an opposite polarity to that expected for an axial dipole were mostly located in the Southern Hemisphere especially in the South Atlantic and Indian regions FIGURE 1. Geomagnetic field on January 1, 2020. (A) Intensity at the surface and (B) radial component (Br) of the geomagnetic field at the CMB on January 1, 2020, from CHAOS-7.2 model (Finlay et al., 2020). The white line in (A) marks the contour line of 32,000 nT to highlight the area of the SAA defined following De Santis et al. (2012) In (B) the two RFPs related to the presence of the SAA at the surface are observed in red colors in the Southern Hemisphere We use CHAOS-7.2 model until degree 13 to calculate the intensity at the surface and until degree six for Br at the CMB In the search for understanding geomagnetic jerks, an important element is to investigate possible correlations between these events and some other geophysical phenomena (see Mandea et al., 2010 for a review on some of the up-to-date suggested links) we suggest that the minima of the acceleration of the areal extent of SAA could be a reliable indicator of the occurrence of geomagnetic jerks being able to register all of the well-defined geomagnetic jerks for the last 2 decades and then provide a discussion about the dynamic processes at the CMB that could be involved in this link and the possible identification of future geomagnetic jerks occurrence from this result This study has been carried out using the CHAOS-7.2 model, the release of the CHAOS-7 model (Finlay et al., 2020) that uses the Swarm preliminary baseline 0603 data up to the end of March 2020 and ground observatory data as available in February 2020. The Swarm satellite mission (Olsen and Haagmans, 2006 and references therein) was launched by ESA in November 2013 based on a constellation of three identical satellites (Alpha provides high quality measurements of the geomagnetic field in three different orbital planes with Alpha and Charlie flying almost in parallel and Bravo orbiting alone at a higher altitude along with those given by other previous satellite missions (Cryosat-2 and Ørsted) and the global network of magnetic observatories at ground level provide the possibility of obtaining high-resolution time-dependent geomagnetic field models such as the CHAOS-7 model and later releases we use the finite differences between successive times with ti+1/2 = ti + 3 months and ti+1 = ti + 6 months and (C) second derivative S ̈ of the areal extent of the SAA for the last 2 decades calculated from CHAOS-7.2 model monthly from January 1998 to March 2020 The fit of the areal extent of the SAA by using cubic splines is plotted in orange in (A) the mean occurrence times of the well-defined geomagnetic jerks for the last 2 decades are marked Shaded bands mark the uncertainty of the occurrence times given by one standard deviation With green arrows some interesting features are indicated (see Discussion in the main text for more details) For the second derivative, S⋅⋅, we use the finite differences method of second order following Tozzi et al. (2009) with ti+1 = ti + 6 months and ti−1 = ti−6 months for the same period Prior to the estimation of these derivatives, we smooth the areal extent of the SAA series by fitting the data using a cubic splines basis with knot points every year from 1998 to 2020.2 in order to avoid subsequent mathematical artifacts from the derivatives (orange line in Figure 2A) As expected, the S˙ values are positive (Figure 2B); that is, the areal extent of the SAA is increasing in the analyzed time interval with an average rate of 4.4 ∙ 105 km2/yr. In Figure 2C it is observed that this increase of the SAA is not continuously accelerated (see also Pavón-Carrasco and De Santis, 2016) alternating periods of accelerations (beginning –1999.0 and 2017.8–2019.6) and decelerations (1999.0–1999.9 The time intervals when the S⋅⋅ reaches positive values (2000.7–2001.1 2014.8– end) are characterized by longer displacements of the areal extent of the SAA These intervals present a duration from 1 to 3 years being the longest period of positive S⋅⋅ the maximum increase of areal extent of the SAA for the last 2 decades the longest period with positive S⋅⋅ would be from 2014.8 up to now but this result must be considered carefully because it could be affected by edge problems of the CHAOS-7.2 model These edge problems could also be present at the beginning of the model the borders being the periods most subject to change in the minima of S⋅⋅ (1999.9 and 2017.8) the areal extent of the SAA is slowing down its advancement - The 1999 geomagnetic jerk occurrence time: occurrence dates of the 1999 geomagnetic jerk were given in Supplementary Table A4 by Pinheiro et al. (2011). They are 54 occurrence dates calculated from the annual means of the geomagnetic components X, Y, and Z in 42 observatories. The mean (and standard deviation) of these 54 occurrence dates provides the value of 1999.0 (±0.9) plotted in Figure 2C - The 2003 geomagnetic jerk occurrence time: the 2003 geomagnetic jerk is identified by a relative peak in number of global jerk identifications between 2002 and 2003 (see Figure 15 in Brown et al., 2013). This interval can be rewritten as 2002.5 (±0.5) and plotted in Figure 2C It is important to note that these observatories are not evenly distributed geographically More space and time extended studies of magnetic observatories could result in more accurate estimations of the occurrence times of these jerks As we can observe, the minima of the acceleration (S⋅⋅) of the areal extent of the SAA (Figure 2C) coincide quite well with the geomagnetic jerks occurrence for the last 2 decades The main differences are found in the earlier times but within the uncertainty shown by shaded bands where the edge effects could be more significant by the effect of the smoothing of the splines basis used to represent the temporal variations during the modeling process Despite some discrepancies mainly due to edge effects these tests confirm the results obtained with CHAOS-7.2 Secular acceleration of the areal extent of the RFPs at the CMB Time evolution of the second derivative of the areal extent of the South American (blue line) and African (red line) RFPs and (green line) the sum of both areal extents at the CMB The areal extent is calculated as the area within the contour line of −32,000 nT of Br (shown in the map in the figure) using CHAOS-7.2 model until degree 6 With green arrows other interesting features are indicated (see Discussion in the main text for more details) This lack of synchronization between RFPs makes it difficult to provide an accurate estimation of the time occurrence of the minima when both RFPs are considered together and it reveals the complexity of the mechanisms involved This means that in the minima of the second derivative of the areal extent of the RFPs which seem to be associated with the occurrence of the geomagnetic jerks there is a decrease in the rate of evolution of the areal extent of the RFPs: the African RFP slows down its extent (slow reinforcement of Br) and the South American RFP vanishes slower (slow weakening of Br) This behavior could be due to a weakening and later reinforcing of the upwelling of toroidal field from the core in the case of the African RFP and vice versa for the South American RFP This is also observed when the average is calculated on the region where the RFPs associated with the SAA are located which reinforces the link between SAA and jerks it is worth to mention that observed SA might be a time average of the true instantaneous SA especially when using geomagnetic field models with temporal damping This could be a limitation to correlate on a very accurate way some features of the SA in time Averaged secular acceleration of the geomagnetic field at the CMB Time variation of the averaged squared secular acceleration of the Br calculated using maximum spherical harmonic degree six at the CMB we consider only positive lobes of the SA of Br for average we consider only negative lobes of the SA of Br we consider the SA of Br in the region where the RFPs associated with the SAA at surface are located at the CMB (between 20°S and 70°S in latitude and between 90°W and 70°E in longitude) the analysis of the second derivative of the areal extent of SAA demonstrates to be a promising instrument to identify this kind of poor-defined jerks Further investigations will be needed in order to confirm these possibilities Whether the trend of the SAA areal extent does not change, the detection of a relative maximum of S⋅⋅ of the SAA could indicate coming geomagnetic jerks with around 1.5 years in advance, according to Figure 2C. This is within the mean time of 6–7 years after which no reliable prediction for the field can be made following Qamili et al. (2013) where a longer period of around 5–10 years is also identified Wavelet analysis with Morlet basis functions of (upper panel) the global averaged squared secular acceleration of the radial component (Br) of the geomagnetic field at the CMB (middle panel) second derivative (acceleration) of the areal extent of the South American and African RFPs and (bottom panel) the second derivative (acceleration) of the areal extent of SAA for the last 2 decades The shaded plot indicates the nonsignificant part of the analysis and the black lines mark the common period found The relation between geomagnetic jerks and pulses of the global averaged squared SA of the Br at the CMB seems clear from Figure 4 (see also Chulliat et al., 2010; Chulliat and Maus, 2014; Kloss and Finlay, 2019) but also with the SAA (even if with lower amplitudes between 2006 and 2014) as shown by the blue curve of the same figure This means that possibly the particular core dynamics associated with the SAA is related to the detection of jerks at surface; that is the SAA area is a region especially sensitive for the identification of geomagnetic jerks Chulliat and Maus (2014) carried out a Principal Component Analysis to determine the variability modes (Empirical Orthogonal Functions EOF) of the SA of the geomagnetic field at the CMB associated with the occurrence of geomagnetic jerks Three principal modes were obtained: EOF #1 and EOF #2 presented maxima and minima lobes of the SA located in low and middle latitudes of the Atlantic sector (where the SAA is located nowadays); EOF #3 was characterized by maxima and minima of the SA in the Indian sector Secular acceleration of the Br of the geomagnetic field at the CMB Maps of the secular acceleration of the Br at CMB for January 1 for every year during the last 2 decades We use CHAOS-7.2 model until degree six to calculate the Br this could mean that when the upwelling of toroidal field presents a change associated with a minimum in the second derivative of the areal extent of the RFPs and We suggest a previously unreported link between the minima of the second derivative of the areal extent of SAA at surface and the occurrence of geomagnetic jerks for the last 2 decades by studying the areal extent of the RFPs associated with the presence of the SAA at surface We have seen that global SA pulses at the CMB related to the occurrence of the geomagnetic jerks are also detected locally on the area at the CMB affected by the RFPs associated with the presence of the SAA at surface We have seen that the areal extent of SAA is able to detect through its relative minima all impulses of the geomagnetic field at surface (and This fact is of particular interest because it could shed light on geomagnetic jerks identified in some the occurrence of the 2005.0 geomagnetic jerk is discussed detected as a minimum of the second derivative of the areal extent of SAA could be an impulse of the geomagnetic field associated with the asymmetry of the positive and negative lobes of the SA of the geomagnetic field at the CMB It could be considered as a new kind of impulse of the geomagnetic field but also as a poor-defined jerk It is also important to take into account that the jerks can be poorly defined particularly when we have to distinguish between successive events in disparate regions of the globe that overlap in time this work is encouraging because it aims to give links to effects at the CMB that help to simplify the view of the surface expressions it could be possible that the relation between the arrival of quasi-geostrophic Alfvén waves at the CMB and the presence of nonzonal azimuthal flow accelerations of alternating sign could affect the upwelling of toroidal field present in higher latitudes When a rapid change of the sign of these flow accelerations is produced this would coincide with a change of the upwelling regime observed as a minimum in the second derivative of the areal extent of the RFPs at CMB and of the SAA at surface This could provide an important hint about the dynamic processes that link the RFPs and with the geomagnetic jerks at the interior of the Earth The original contributions presented in the study are included in the article/Supplementary Material further inquiries can be directed to the corresponding author SAC developed the project and performed the calculations with the help of FJPC The interpretation of the results and writing were led by SAC with the help of FJPC and EQ discussed the results and commented on the manuscript The Living Planet Fellowship (TEMPO project) from ESA is the main financial support to this research ASI Limadou-Science Project has supported this work partially Grant FPU17/03635 from the Spanish Ministry of Education was funding AGL PhD thesis FJPC was partially supported by the Spanish research project PGC2018-099103-A-I00 The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest The authors are very grateful to Editor and two reviewers for their useful comments that have helped to improve the quality of this manuscript The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/feart.2020.607049/full#supplementary-material Worldwide wavelet analysis of geomagnetic jerks CrossRef Full Text | Google Scholar Amit, H., Terra-Nova, F., Lézinm, M., and Trindade, R. 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Volume 13 - 2019 | https://doi.org/10.3389/fnana.2019.00039 Subplate (SP) neurons are among the earliest-born neurons in the cerebral cortex and heterogeneous in terms of gene expression SP neurons consist mainly of projection neurons which begin to extend their axons to specific target areas very early during development the relationships between axon projection and gene expression patterns of the SP neurons we analyzed the corticocortical projections of L6b/SP neurons in the mouse cortex and searched for a marker gene expressed in L6b/SP neurons that have ipsilateral inter-areal projections Retrograde tracing experiments demonstrated that L6b/SP neurons in the primary somatosensory cortex (S1) projected to the primary motor cortex (M1) within the same cortical hemisphere at postnatal day (PD) 2 but did not show any callosal projection This unilateral projection pattern persisted into adulthood Our microarray analysis identified the gene encoding a β subunit of voltage-gated potassium channel (Kcnab1) as being expressed in L6b/SP Double labeling with retrograde tracing and in situ hybridization demonstrated that Kcnab1 was expressed in the unilaterally-projecting neurons in L6b/SP Embryonic expression was specifically detected in the SP as early as embryonic day (E) 14.5 Double immunostaining experiments revealed different degrees of co-expression of the protein product Kvβ1 with L6b/SP markers Ctgf (88%) suggesting molecular subdivision of unilaterally-projecting L6b/SP neurons scattered expression of Kcnab1 was observed during postnatal stages without layer specificity Among splicing variants with three alternative first exons the variant 1.1 explained all the cortical expression mentioned in this study our data suggest that L6b/SP neurons have corticocortical projections and Kcnab1 expression defines a subpopulation of L6b/SP neurons with a unilateral inter-areal projection expression of SP-specific genes at a critical period during development almost certainly underlies the fine orchestration of SP axon projection pattern and regulates cortical maturation the relationship between molecular identity and axon projection target specificity remains largely elusive We found a proportion of L6b/SP neurons that project unilaterally from S1 to M1 can be molecularly identified by a specific splice variant of the voltage-gated potassium channel Kcnab1 This discrete group of neurons was present at different stages of development although the expression pattern of Kcnab1 changed as the brain matured There was also a considerable overlap between the Kvβ1-positive neurons in L6b/SP with known L6b/SP molecular markers our results suggested that this molecularly distinctive group of neurons is most likely a L6b/SP subpopulation that survives as the cortex develops and may underlie inter-areal circuit establishment in the cortex Wild-type ICR mice were used in this study and the animals were purchased from SLC Japan and housed under standard conditions with food and water ad libitum and maintained on a 12-h light/dark cycle Embryonic day (E) 0.5 was defined as 12:00 noon on the day when the vaginal plug was found animals were deeply anesthetized by intraperitoneal injection of a combination anesthetic (MMB: 0.3 mg/kg of medetomidine and 5.0 mg/kg of butorphanol) and intracardially perfused with ice-cold phosphate buffered saline (PBS) followed by 4% paraformaldehyde (PFA) Whole brains were carefully dissected after perfusion and post-fixed in 4% PFA overnight at 4°C then transferred to 30% sucrose solution (≥24 h or until brain sinks to the bottom of the tube at 4°C) the embryos were collected from pregnant dams (wild-type ICR) and the brains were immediately dissected from the embryos and post-fixed in 4% PFA overnight at 4°C The dams were sacrificed with cervical dislocation after administration of five doses of MMB All animal experiments were approved by the Animal Research Committee of University of Fukui and the Animal Experimentation Committee of Osaka University and performed in accordance with the Regulations for Animal Research at the University of Fukui and the Regulations on Animal Experimentation at Osaka University Postnatal day (PD) 2 and 3-week-old (PW3) mice were used in the retrograde tracing experiments. PW3 mice were anesthetized and fixed on a stereotaxic frame, and tracer was injected into the cortex according to coordinates determined based on the mouse brain atlas (Paxinos and Franklin, 2008) Tracer used in this study was 2% Fluoro-Gold (Fluorochrome) in distilled water; 0.5% Cholera Toxin Subunit B conjugated with AlexaFluor 488 (Thermo Fisher Scientific) in PBS; or 2% Green RetroBeadsTM IX (Lumaflour) in PBS and all tracer mixtures were added with 0.1 μg/ml Fast Green the anterior/posterior (AP) coordinates were referenced from Bregma the medial/lateral (ML) coordinates were the distance from the midline at Bregma and the dorsal/ventral (DV) coordinates were measured from the pial surface of the brain All measurement units were in mm and are referred to in the following description as [anterior/posterior (AP) Three and six injection sites were selected for both M1 and S1 0.8); whereas the stereotaxic coordinates for injection into S1 were (0.0 Each animal received pressure injection (approximately 40 nl/site) of a tracer delivered via a glass needle (pulled and broken at the tip with forceps to make an opening with a diameter of 40–60 μm) attached to a Hamilton syringe animals were transcardially perfused and the brains were processed as mentioned above Images of the whole FG-injected brains were taken with a fluorescence stereomicroscope (MZ 10F and only the brains that appeared to have sufficient injection were subsequently sectioned The selected brains were embedded in O.C.T compound (Sakura) and stored at −80°C then cut into 14–16 μm sections on a coronal plane using a freezing microtome (Leica model CM3050S) Sections were imaged with BZ-X700 (Keyence) using an appropriate filter cube for FG (ET DAPI/FluoroGold the animals were anesthetized by hypothermia and tracer was injected by using a Picospritzer® II microinjector (Parker Hannifin The injection targets (M1 and S1) were estimated based on parallel experiments whereby the injected mouse was raised to adulthood and injection sites in M1 and S1 were traced to confirm the point of injection injection in M1 and S1 were estimated as referral points from the midline (x) and the most rostral edge of the cortex (y) y: 2.0 mm; and S1 was x: 2.5–2.8 mm and y: 3.0–3.5 mm The mice were let to recover on heated pads and returned to the dams for survival The mice were perfused 2 days post-injection at PD4 and the brains were processed and imaged as mentioned above The genes preferentially expressed in association neurons (projecting from S1 to ipsilateral M1) compared to those in callosal neurons [projecting from S1 to contralateral S1 (cS1)] were identified with DNA microarray screening cortical layer 2/3 neurons were transfected with pCAGGS-tdTomato by performing in utero electroporation at E15.5 and the mice that had tdTomato labeling of cell bodies in S1 were used in the subsequent procedure The retrograde tracer Green RetrobeadsTM IX was injected at PD21 into either M1 or cS1 with the help of red fluorescence of tdTomato in these areas (in axon terminals projecting from S1) Mice were transcardially perfused with ice-cold PBS and the brains were dissected out Fresh-frozen sections were cut at 10 μm thaw-mounted onto glass slides covered with polyphenylene sulfide membrane and air-dried immediately The labeled association neurons in layers 2/3 and labeled callosal neurons in layers 2/3 and 5 were collected from S1 (more than 1,000 cells each) using a laser-captured microdissection system (AS-LMD Total RNAs were prepared using NucleoSpin RNA XS kit (Macherey-Nagel) Biotin-labeled and fragmented using OvationTM Pico WTA System Labeled cDNAs were hybridized to the GeneChip Mouse Gene 1.0 ST Array (Affymetrix washing and scanning were performed with a GeneChip 3,000 7G system (Affymetrix Raw signals were subjected to Log-transformation and centering in order to obtain processed signals for cross-sample comparison The candidate genes preferentially expressed in L6b were selected using Subio Platform (version 1.14 The microarray data were deposited at Gene Expression Omnibus (GEO) under the accession number GSE123351 cDNA fragments of Kcnab1 and Ctgf were PCR-amplified from mouse brain cDNA with the following primer pairs Kcnab1-fwd.: 5′ GAAATGGGGTGCCAGAAA 3′; rev.: 5′ ATTGTACAGGGCCAGGCA 3′; Ctgf-fwd.: 5′ AGAGTGGAGCGCCTGTTCTA 3′; and rev.: 5′ ACTGGCAGAGTGGTGGTTCT 3′ In order to examine the expression pattern of Kcnab1 splicing variants Kcnab1.1 in situ probes were generated to specifically recognize each of the subunits The primer sets used were as follows: Kcnab1.1-fwd.: 5′ CAGCCGAGATCACAGCCTG… 3′; rev.: 5′ CTGCTTTGCGGTGGACTCTT… 3′; Kcnab1.2-fwd.: 5′ ATAAACCTGCCTGTGCAGA… 3′; rev.: 5′ CATGCCTGTCTTTGCCTTG… 3′; Kcnab1.3-fwd.: 5′ AGGCAGATAGGAACTTCCAG… 3′; rev.: 5′ GCTCGCAGAGCTTTAGGT… 3′ Amplified fragments were cloned into pGEM-T vector (Promega) In vitro transcription of cRNA probes was performed with T7 or SP6 RNA polymerase (Roche) using the template plasmids linearized with an appropriate restriction enzyme and RNA DIG labeling mix (Roche) according to the manufacturer’s instructions In situ hybridization histochemistry (ISHH) was performed as described before (Yagi et al., 2016) using cryosections (14–16 μm) prepared from mice at E12.5 The cryosections were air dried for 1 h and fixed in 4% PFA in PBS for 10 min at room temperature The sections were then incubated in 0.2 M HCl for 10 mins followed by permeabilization with Proteinase K (7.9 μg/ml; Roche) digestion for 10 min at 37°C Concentration and treatment duration of Proteinase K were halved for the brain samples younger than PD4 the sections were treated with acetic anhydride in 0.1 M triethanolamine for 10 min The slides were rinsed with PBS in between each step the sections were transferred to 5× saline sodium citrate (SSC) for 10 min or longer Hybridization was carried out with the generated probes in hybridization buffer (50% formamide 200 μg/ml yeast tRNA) overnight for at least 16 h at 55°C High-stringency washes were carried out in the following steps: 5× SSC 20 min at room temperature; 2× SSC 20 min at 65°C; two washes with 0.2× SSC 20 min at 65°C and lastly the slides were transferred to PBS at room temperature Detection of specific hybridization was performed using anti-Digoxigenin coupled with alkaline phosphatase and subsequently visualized using nitro blue tetrazolium chloride/5-bromo-4-chloro-3-indolyl-phosphate (NBT/BCIP) Sense probes were used as negative controls and no signals were observed with the sense probes Bright field images of the stained sections were taken with BZ-X700 Brain cryosections were prepared from adult mice (PW8–PW24) and the sections were processed accordingly for double immunofluorescence labeling After air-drying for an hour at room temperature the sections were treated with Tris EDTA buffer (pH 8.5) for 1 min at 105°C in the autoclave or for 30 min at 85°C in the water bath three rinses) in PBS before blocking the sections with 5% normal donkey serum The sections were then incubated in primary antibodies (diluted in blocking solution) overnight at 4°C The primary antibodies used in this study were as follows: CaMKIIα (1:100; rabbit; GeneTex This was followed by incubation in species-specific fluorescent secondary antibodies (Donkey anti-mouse IgG Alexa Fluor 568 and either Donkey anti-rabbit IgG Alexa Fluor 488 or Donkey anti-goat IgG Alexa Fluor 488 All secondary antibodies were diluted at 1:200 in PBS Nuclear staining was performed using 4′,6-diamidino-2-phenylindole (DAPI) Fluorescence signals were imaged with a laser scanning confocal microscope (LSM 880 with Airyscan Immunohistochemistry against Fluoro-Gold was combined with ISHH sections were incubated with anti-Fluoro-Gold (FG; 1:500; rabbit; Millipore Immunoperoxidase labeling was performed using a Vectastain Elite ABC Kit (Vector) and a DAB detection kit (Vector) was used for detection according to the manufacturer’s protocol Mouse homologues for exons 1.2 and 1.3 of the human Kcnab1 gene were identified by T-BLAST-N search in Ensembl genome database (GRCm38.p61) with the human sequences as queries. The genomic regions encompassing the hit sequences and exon 2 were then subjected to exon/intron prediction with GeneWise2 The identified sequences were deposited at the DNA Data Bank of Japan (DDBJ) under the accession numbers LC437679 for exon 1.2 and LC437680 for exon 1.3 The TPM (Transcripts per million) data for Kcnab1, Ctgf, Cplx3, and Nurr1 (Nr4a2) genes across 1809 individual cells isolated from the mouse primary visual cortex (V1) were obtained from the GEO3 (accession, GSE 71585; Tasic et al., 2016) Genes were considered as being expressed in a cell when the TPM value in the cell was 10 or larger The percentage of cells expressing Kcnab1 at two different expression levels (TPM ≥ 10 and TPM ≥ 100) was calculated for each of the eight broad types of cortical cells (astrocytes The percentages were also calculated for glutamatergic neurons in different layers and seven classes of GABAergic neurons by combining the numbers of cells for primary cell types in each layer or class The percentages of cells expressing each of the four genes were calculated for two primary cell types for L6b (Rgs12 and Sepinb11) To specifically examine if Kcnab1 is expressed in GABAergic neurons in L6b the percentages of cells expressing Kcnab1 among 41 cells (containing 33 glutamatergic neurons and eight GABAergic neurons) dissected from L6b of V1 were also calculated Similar analyses were performed using other RNAseq data for the four genes across 3,005 individual cells isolated from mouse S1 and hippocampal CA1 (Zeisel et al., 2015). The annotated expression data (equivalent to the raw data in GEO with the accession GSE60361 except for the cell type annotations) were obtained from the website of Linnarsson lab4 The percentages of Kcnab1-expressing cells (expression score ≥ 1) were calculated for Level-1 classes of cell types and for Level-2 classes of interneurons and pyramidal neurons Those of cells expressing each of the four genes were calculated for L6b cells The retrograde labeling experiments showed the same results when repeated with two other tracers; fluorescence conjugated-cholera toxin B (CTB) and Green RetroBeadsTM (data not shown) Retrograde tracer injection in M1 of PW3 mouse brain labeled unilaterally-projecting Layer 6b (L6b)/SP neurons in primary somatosensory cortex (S1) (A,D) Whole mount brain images in a bright field (left) and a fluorescent (right) views showing Fluoro-Gold (FG) injections into primary motor cortex (M1; A) and contralateral S1 (cS1; D) at PW3 (B) Coronal sections of the brain shown in (A) at the level of M1 (left) and S1 (right) (C) Higher magnification view of the boxed area in (B) (E) A coronal section of the brain shown in (D) at the level of S1 (F) Higher magnification view of the boxed area in (E) (G,J) Whole mount brain images in a bright field (left) and a fluorescent (right) views showing FG injection into M1 (G) and cS1 (J) at PD2 (H) Coronal sections of the brain shown in (G) at the level of M1 (left) and S1 (right) (I) Higher magnification views of the boxed area in (H) (K) A coronal section of the brain shown in (J) at the level of S1 (L) Higher magnification views of the boxed area in (K) and (L) indicate borders of cortical layers We next asked if this projection pattern is consistent throughout postnatal development. When FG was injected at PD2, we found FG-labeled SP neurons at PD4 for tracing from M1 (Figures 1G–I), but not for tracing from cS1 (Figures 1J–L) similar to the results in L6b neurons in PW3 animals L6b/SP neurons in the S1 area projected their axons unilaterally to the M1 area As we found that its expression was specific to SP in the embryonic stages (see below) we focused on the analysis of Kcnab1 in this article Microarray screening identified Kcnab1 and Ctgf as expressed in L6b (A) Green RetroBeadsTM was injected into M1 (left panel) or cS1 (right panel) of the brains at PD21 that had been electroporated with pCAGGS-tdTomato at E15.5 Green and red fluorescent images were overlaid onto the bright field image (B) Relative expression levels of Kcnab1 (blue) and Ctgf (orange) among association neurons in L2/3 and L6b and callosal neurons in L2/3 and L5 compared by microarray analysis (C,D) In situ hybridization histochemistry (ISHH) for Kcnab1 (C) and Ctgf (D) was carried out on coronal sections of mouse brain at PD21 Higher magnification view of the boxed area is shown on the right of each panel Dashed lines in these high magnification images indicate borders of cortical layers 500 μm and 100 μm for low and high magnifications From our retrograde tracing experiments and microarray gene analysis we were inclined to hypothesize that association neurons in L6b/SP were molecularly distinctive brains that were injected with retrograde tracer were processed for ISHH and immunohistochemistry to confirm this hypothesis at the neonatal stage (injection at PD2 and brains fixed at PD4) a proportion of association neurons in L6b/SP expressed Kcnab1 (data not shown) Since L6b/SP neurons with a unilateral projection expressed Kcnab1 at both the neonatal and postnatal stages, we set out to examine the onset of Kcnab1 expression in the mouse cortex and whether the expression pattern was maintained throughout development. First, we carried out ISHH for Kcnab1 on coronal sections of the mouse brain at different embryonic stages. Kcnab1 expression was observed in the SP as early as E14.5 (Figure 4) Kcnab1 expression was consistently restricted to the SP and not detected in other layers throughout embryonic development Kcnab1 has an earlier onset in comparison to the established L6b/SP marker Ctgf of which the earliest expression was detected at E16.5 among the stages tested Kcnab1 expression in developing mouse cortex was detected as early as E14.5 (A) ISHH for Kcnab1 (a–d) and Ctgf (e–h) was carried out on coronal sections of the mouse brain at different embryonic stages (E12.5 Kcnab1 expression was observed starting at E14.5 and it began earlier when compared to Ctgf expression (B) Higher magnification of boxed regions in (A) Kcnab1 expression was restricted to the SP during the embryonic stage (b′–d′) Together with the expression during the embryonic stage these data showed that Kcnab1 is expressed in a bipartite manner: a stable expression in the L6b/SP throughout the cortical development and a dynamic expression in other layers that appears postnatally Kcnab1 expression pattern changed during postnatal development (A) ISHH for Kcnab1 was carried out on coronal sections of the mouse brain at selected postnatal stages (PD3 (B) Higher magnification view of boxed regions in (A) Weak Kcnab1 expression was detected in deep layers above L6b at PD3 (a,a′) Kcnab1 expression gradually spread to the more superficial layers and some cells with higher expression appeared (b,b′) becoming evidently scattered in the upper layers at PD25 (c,c′) Ctgf was limited to L6b throughout postnatal development (d–f; d′–f′) Dashed lines in (c′) and (f′) indicate borders of cortical layers Kcnab1-expressing neurons constitute a distinct subpopulation of L6b/SP neurons This held true also for early postnatal stage PD3 (data not shown) the expression pattern of Kcnab1 described in this study was explained by that of the variant 1.1 alone Kcnab1 splice variant Kcnab1.1 was expressed in the mouse cortex (A) Genomic structure of 5′ part of the Kcnab1 gene locus showing three alternative first exons (exons 1.1–1.3) Filled and open bars indicate coding and non-coding part of the exons (B) Amino acid sequence alignments of the three alternative N-terminals of the mouse (m) and human (h) Kvβ1 protein encoded by three alternative first exons The residues in mKvβ1 different from those in hKvβ1 are shown in white letters on black background (C) ISHH for Kcnab1 splice variants was carried out on PD25 mouse brain sections using the probes specific for exons 1.1–1.3 Only Kcnab1.1 expression was observed in the cortex (a) Neither Kcnab1.2 nor Kcnab1.3 was present in any layers of any cortical areas (b,c) Higher magnification of boxed regions in (a–c) is shown in (a′–c′) Dashed lines indicate borders of cortical layers 500 μm (a–c); 100 μm (a′–c′) The main findings of this study are: (1) that a discrete population of L6b/SP neurons project unilaterally from S1 to M1 and no callosal projection was observed; (2) that Kcnab1 identifies a proportion of this subclass of L6b/SP neurons with an inter-areal projection; (3) that Kcnab1 is co-expressed with known L6b/SP markers Ctgf and Nurr1 to different degrees at postnatal stage; and (4) that Kcnab1 expression is restricted to L6b/SP during the early developmental stage but scattered Kcnab1-positive neurons were observed in the upper layers of postnatal cortices it would be most ideal if the tracing experiment is repeated with transgenic reporter line that would allow further characterization of the association neuron subclass the axon trajectory that originates from this area and their targets that may include other cortical regions we have identified a group of L6b/SP association neurons that expressed a specific splice variant of Kcnab1 and the expression in L6b/SP was maintained at all developmental stages This molecular authenticity that spans development could be a plausible mechanism that modulates L6b/SP neuron specification during cortical maturation and this would add to the increasing efforts to characterize L6b/SP neurons thus elucidating the role of L6b/SP neurons in SP development and subsequent brain network establishment All animal experiments were approved by Animal Research Committee of University of Fukui and Animal Experimentation Committee of Osaka University and performed in accordance with Regulations for Animal Research at University of Fukui and Regulations on Animal Experimentation at Osaka University This work was supported by grants from Takeda Science Foundation NOVARTIS Foundation (Japan) for the Promotion of Science and Japan Society for the Promotion of Science (JSPS) KAKENHI [Grant numbers JP23800027 JP26830027 and JP17K07076 (to YO) and JP15K15015 ST was supported by The Ministry of Education Malaysia (University of Malaya HLCB/PK 2015) The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest The microarray screening was supported by the Division of Bioresearch of Life Science Research Laboratory Animal experiments were supported by both the Division Laboratory Animal Resources of Life Science Research Laboratory University of Fukui and The Institute of Experimental Animal Science The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fnana.2019.00039/full#supplementary-material a transient neocortical structure: its role in the development of connections between thalamus and cortex Glutamatergic nonpyramidal neurons from neocortical layer VI and their comparison with pyramidal and spiny stellate neurons Relation between putative transmitter phenotypes and connectivity of subplate neurons during cerebral cortical development Organization and development of corticocortical associative neurons expressing the orphan nuclear receptor Nurr1 Development of layer I and the subplate in the rat neocortex 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Subplate neuron ablation alters neurotrophin expression and ocular dominance column formation Activity-dependent Nurr1 and NGFI-B gene expression in adult mouse olfactory bulb Subplate cells: amplifiers of neuronal activity in the developing cerebral cortex The superior function of the subplate in early neocortical development Cellular physiology of the neonatal rat cerebral cortex: intrinsic membrane properties doi: 10.1002/1097-4547(20001115)62:4<574::aid-jnr12>3.0.co;2-0 Gli3 controls subplate formation and growth of cortical axons Morphology and physiology of excitatory neurons in layer 6b of the somatosensory rat barrel cortex Neocortical layer 6B as a remnant of the subplate—a morphological comparison Subplate neurons pioneer the first axon pathway from the cerebral cortex Alternative splicing of the human Shaker K+channel β1 gene and functional expression of the β2 gene product Synaptogenesis in purified cortical subplate neurons Transcriptional landscape of the prenatal human 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labeling study Novel interneuronal network in the mouse posterior piriform cortex Functional excitatory microcircuits in neonatal cortex connect thalamus and layer 4 Akiyama H and Sato M (2019) Kcnab1 Is Expressed in Subplate Neurons With Unilateral Long-Range Inter-Areal Projections Received: 10 December 2018; Accepted: 20 March 2019; Published: 03 May 2019 Copyright © 2019 Tiong, Oka, Sasaki, Taniguchi, Doi, Akiyama and Sato. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) *Correspondence: Makoto Sato, bWFrb3NhdG9AYW5hdDIubWVkLm9zYWthLXUuYWMuanA= † These authors have contributed equally to this work senior vice-president for marketing in products and markets at Seagate to look at how spinning disk can get to 40TB and 50TB We talk about hard disk drive technologies such as heat-assisted magnetic recording (HAMR) that can boost areal density and pack more data onto disk platters Feist also talks about the future of hard disk drives (HDDs) and the use cases suited to them Great question. Thanks for the time this morning. It’s just an amazing time to be part of the hard drive industry and with all of the markets starting to rebound it’s a great time to innovate and provide the ability to have data storage devices at scale The innovations that are underway right now are driven by a lot of contributions across many different disciplines We have great engineers working in our supply chain to allow us to have mechanical innovations to have recording physics innovations with magnetic recording and to put more information on every disk inside a hard drive And we have amazing wafer and media metrology underway to continue to improve our process control our repeatability and our ability to extract more areal density out of every drive Areal density is really what’s at the forefront of development for hard drives           • Download this podcast • It has been for years and will continue to be for years to come and there’s a number of new techniques and new processes that we have access to with technologies that are now becoming more readily available [These include] better simulation, more use of GPUs [graphics processing units] to do things with artificial intelligence [AI] to allow us to find design spaces that we didn’t have access to before with speed and all that creates a recipe that our engineers are taking advantage of and allowing us to bring larger and larger capacity drives to our customers We’ve seen the hard drive industry bring forth 28TB hard drives and we’ve seen Seagate deliver 3TB per platter samples to the industry and I think as an industry we’ll continue to drive that areal density in that terabyte per disk increase We’ll see delivery of 4TB per disk and 5TB per disk in the not too distant future All of that served on a 10-disk hard disk drive itself, so delivering 40TB and 50TB disk drives in the near future. Really, really exciting. The basis for those capacity increases are really driven by heat-assisted magnetic recording (HAMR) innovation investment and development over the last 15 to 20 years Just as perpendicular recording had served the hard drive industry for the last 20 years we believe that HAMR will serve the industry for years to come All of this really comes at the right time in the sense that cloud storage demand is growing and the use of cloud continues to grow the demand curve really helps us continue to stay focused on that innovation and make sure we’re delivering larger hard drives to meet that use case This is a question that we get asked routinely It’s one that we have a lot of fun answering in the sense that we work very closely with the largest customers in the world and we have a diverse set of customers We have a video and information and analytics business All of these routes to market are slightly different and they all have the need for increasing data storage It’s exciting and the new use cases that you hear a lot about It shows the importance and the relevance of data on making decisions and creating a society that’s informed and has data at their fingertips The innovation is underway now and you’re going to see a significant transformation in how large capacity drives are used and how clouds take advantage of those economies of scale You can see new businesses depending on hard drives for their ecosystem development social media companies and the growth of video are all very well suited to what hard drives provide: very large capacity efficient sustainable storage architectures scalable architectures that allow us to have presence in multiple geographies around the globe [And] there are new use cases with all of these video applications for prosumers and content creators which are now taking advantage of tools with generative AI to do text-to-video and creating larger All those things are good for data storage and HDDs have been the backbone of data storage needs at exabyte scale Organizations must take steps to ensure compliance with emerging rules targeting foreign adversaries' access to U.S A former federal deputy CIO testified that reauthorizing the Technology Modernization Fund will help the government continue IT .. Providing detailed background information is one way to help data privacy regulators during investigations of potential .. Dashlane CEO John Bennett tells Dark Reading’s Terry Sweeney that the advent of shadow AI use means that some AI agents and .. Staying ahead means cyber defenders can’t operate in silos The launch of IBM’s Autonomous Threat Operations Machine and X-Force Predictive Threat Intelligence agent were announced at the .. Cilium's Hubble tool provides network observability while working in Kubernetes This guide explains how Hubble works and how to .. A new 'digital circuit breaker' capability for HPE Private Clouds increased visibility of third-party hardware with OpsRamp and .. The accuracy and relevance of AI responses are directly influenced by the quality of the prompt Rocky Linux and AlmaLinux are RHEL-compatible distributions created after Red Hat announced the discontinuation of CentOS in 2020.. 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The database vendor plans to add support for Model Context Protocol and automated vector embedding capabilities to make it faster.. landowner face off over removal of barbed wire fencing in tenanted field; posse of policemen and MLA rush to avert law and order situation; Police seek ownership documents from tenant Tension rent the air at Sao Jose de Areal after local residents protested over the damage to a barbed wire fencing in a tenanted land apparently to make way to the statue of Shivaji Maharaj The barbed wire fencing and stones damaged MARGAOAhead of the Shiv Jayanti celebrations on February 19 tension rent the air at Sao Jose de Areal on Monday bringing face to face the local residents and the landowner Mehboob Makandar over the damage and removal of barbed wire fencing in a tenanted field apparently to pave way for an access to the adjoining property playing host to the statue A team of Maina-Curtorim police led by PI Arun Desai rushed to Areal with a posse of policemen to avert a law and order situation The police were later joined by Salcete Mamlatdar Vimod Dalal to work out a solution Velim MLA Cruz Silva also made his presence at the site later in the evening The area had witnessed tension and violence last year around the same time after a group of persons carried Shivaji’s statue for installation on a hilly land Local residents maintained they are neither against Shivaji Maharaj nor his statue they insisted the core issue facing Benabhat is not Shivaji’s statue Tension started on Monday noon after local residents rushed to Benabhat following reports that the owner of the adjoining plot where a statue of Shivaji Maharaj was installed in his property last year allegedly started clearing the fencing in a tenanted field ahead of his plot Landowner Makandar told the media that he had come to his property in view of the Shiv Jayanti celebrations scheduled on Wednesday only to find barricading and fencing of the plot in question the local residents came in large numbers and stopped us They also blocked my car by placing stones near the tyres,” he said who claimed to be the tenant of the plot in question said he had fenced his plot as he had cultivated paddy and had drawn up plans to go for the second crop He alleged that the fencing and barricading was dismantled and damaged and demanded restoration of his barbed wire fencing Local residents questioned PI Arun Desai when he asked the tenant Cruz Tereza to produce his document claiming tenancy or land ownership to the barricade plot in question insisting that the police officer should first ask Mehboob Makandar to produce documents or any order authorising him to enter the tenanted plot and remove the fencing Another property owner grants consent for alternate access to Shivaji statue MARGAO: After discussions between the authorities and the local residents and the Shiv Premis it was finally agreed to use an alternate access to go to the statue of Shivaji Maharaj on Shiv Jayanti celebration on February 19 Bajrang Dal leader Viraj Desai and Salcete Mamlatdar Vimod Dalal later told the media that the issue over the access to the Shivaji statue has been resolved after an owner of an alternate property has consented to provide access to the statue from his property Bajrang Dal leader Viraj Desai said the organisation has agreed to the alternate access to the Shivaji statue even though he said nothing would have prevented its members from going to the statue through the other property Out of respect for law and the advice of the authorities we have accepted the alternate route,” he said He added: “The Shivaji statue at Sao Jose de Areal would have been a perfect example of community harmony in Goa the land to install Shivaji statue has been provided by a Muslim owner and the village is inhabited by the Christian population Shiv Jayanti is a victory celebration and an important event for the Hindus We do not know why the people are creating issues over the statue and land access,” he said This includes the following streams and drainages… Dodd Creek – Some locations that will experience flooding include…Floyd Comment * document.getElementById("comment").setAttribute( "id" "a3bfc73ca0e568bc359102132626ac8c" );document.getElementById("d718f084d2").setAttribute( "id" HOLOPLOT’s X1 system was chosen to provide the sound for The Atmosphere stage at Tomorrowland a custom-made circus-top tent featuring DJs The system utilised two main arrays consisting of six X1 modules each The key challenges to overcome were the highly reflective surfaces causing echoes in the listening area preventing an even sweet spot to fully benefit from the immersive content played at the stage Sound Engineer at Noizboyz and Co-Founder of stereo upmixing solution Areal is responsible for the sound design of all 16 stages at Tomorrowland and chose the HOLOPLOT system for the audio experience at Atmosphere “I was really shocked with the sound quality that was achievable because I expected beamforming to decrease it,” he said It’s amazing how the quality rises when you just focus audio on the people and don’t create any reflections and that improves the immersive experience In the spirit of technological advancement had already developed a new piece of software allowing them to upmix stereo signals into multi-channel content in real time This had been used at Atmosphere for a couple of years already but the size of the tent and the required distributed system had still proven challenging for the designers in the past with the additional loudspeakers needed to achieve the surround sound effects causing increased reflections and confusion in the diffuse field delivering the results of the upmixed content via Areal to the crowd without echos Enabling this are the two core pillars of HOLOPLOT technology 3D Audio-Beamforming and Wave Field Synthesis “Both allow us to control sound in the 3D space,” stated Sebastian Boeldt “We can precisely shape the coverage areas in the audience zone but also avoid certain shapes of the venue minimising reflections and improving the clarity of the performance.” also allows the precise gain and delay alignment between them “This means we can increase the immersive sweet spot and minimize the delay spread a key parameter when designing immersive systems,” Boeldt explained “The combination of sound control via avoidance of the tent surfaces and division of the crowd into time aligned coverage zones create a perfect base canvas for the Areal technology to shine It’s a really flexible piece of software that paired beautifully with the X1 system.” “The widespread misconception that loud is always better doesn’t apply here and thanks to the isolated yet aligned zones X1 created and the multi-channel content from the Areal engine we achieved great results giving that small immersive club feeling,” concluded Doms holoplot.com We are using cookies to give you the best experience on our website You can find out more about which cookies we are using or switch them off in settings This website uses cookies so that we can provide you with the best user experience possible Cookie information is stored in your browser and performs functions such as recognising you when you return to our website and helping our team to understand which sections of the website you find most interesting and useful Strictly Necessary Cookie should be enabled at all times so that we can save your preferences for cookie settings we will not be able to save your preferences This means that every time you visit this website you will need to enable or disable cookies again More information about our Cookie Policy Volume 7 - 2019 | https://doi.org/10.3389/fchem.2019.00869 This article is part of the Research TopicNext-generation Electrochemical Energy Storage DevicesView all 13 articles Self-supported electrodes represent a novel architecture for better performing lithium ion batteries lower areal capacity restricts their commercial application we explore a facial strategy to increase the areal capacity without sacrificing the lithium storage performance A hierarchical CuO–Ge hybrid film electrode will not only provide high areal capacity but also outstanding lithium storage performance for lithium ion battery anode Benefiting from the favorable structural advance as well as the synergic effect of the Ge film and CuO NWs array the hybrid electrode exhibits a high areal capacity up to 3.81 mA h cm−2 good cycling stability (a capacity retention of 90.5% after 150 cycles) and superior rate performance (77.4% capacity remains even when the current density increased to 10 times higher) There is an increasing concern about fabricating self-supporting electrodes with high areal capacity as well as good electrochemical performance Usually, the self-supporting electrodes cannot maintain good electrochemical performance at very high areal capacity. Herein, we report a hierarchical CuO–Ge hybrid film on CF as a self-supporting electrode with ultrahigh areal capacity for LIB application. As shown in Figure 1 the integrated film was formed by physical vapor deposition of Ge film on CuO NWs array which were grown directly on the CF via a facial and scalable solution approach CuO NWs array with well-defined nanostructure serves as both the active materials and conductive connection for Ge film The porous feature will not only alleviate the drastic volume change during the Li insertion and extraction process but also facilitate the diffusion of electrolyte into the electrode Benefiting from the favorable nanostructures as well as the synergic effect of the Ge film and CuO NWs array the integrated electrode delivers ultrahigh areal capacity this is the first time that CuO NWs combined with Ge film hybrid anode achieved a high areal capacity It could deliver an ultrahigh charge areal capacity up to 3.45 mA h cm−2 after 150 cycles at a current density of 0.8 mA cm−2 and a capacity ~2.98 mA h cm−2 at a current density as high as 4 mA cm−2 Schematic illustration of the fabrication processes of the CuO–Ge hybrid film on Cu foam (CF) The CuO NWs array on CF was placed into an radio frequency (RF) sputtering system (Verios G4 UC Shenyang Lining Co.) using 99.999% pure Ge target The base pressure was 7.8 × 10−4 Pa The mass loading of CuO NWs supported Ge (typically ~0.67 mg cm−2) CuO NWs array (typically ~3.64 mg cm−2) and Ge on pristine CF (typically ~0.45 mg cm−2) were weighed before and after sputtering using a microbalance (OHAUS the Ge film was also deposited on pristine CF under the same deposition parameters The samples were characterized using X-ray diffraction (Rigaku Ultima IV) and Raman spectroscopy (WITEC alpha300 R Confocal Raman system) and the structure and morphology characterization of them were carried out by field-emission scanning electron microscopy (SEM FEI Inspect F50) with accelerating voltage of 5.00 kV and transmission electron microscopy (TEM CR 2032-type coin cells was used to test electrochemical characterizations test cells were assembled in a high-purity argon filled glove box (Mikrouna Technology) with oxygen and moisture level <0.5 ppm The fabricated self-supporting electrodes were used as the working electrode and a Li foil as the counter and reference electrode Lithium hexafluorophosphate (LiPF6) (1 M) in a mixture of ethylene carbonate and diethyl carbonate (1:1 in volume) was used as the electrolyte All the cells were aged for 12 h so that the electrolyte can fully infiltrate the whole cell before measurement Lithium storage performance were evaluated by a multichannel battery tester (Neware BTS-610) in the voltage range of 3.0–0.01 V (Li/Li+) Shanghai Chenhua Co.) was used to evaluate the cyclic voltammetry (CV) at scan rate of 0.1 mV s−1 All the tests were carried out in the thermotank at fixed temperature of 25°C One can note that the strong diffraction peaks of 43.3 which could be indexed to the CF with JCPDS card no There are two weak but identifiable peaks located at 35.5 and 38.8° corresponding to the (−111) and (111) planes of the monoclinic CuO and CuO–Ge hybrid film; (B) X-ray diffraction (XRD) pattern of the CuO–Ge hybrid film (A,B) The top and (C) side view SEM images of CuO NWs array; (D,E) The top and (F) side view SEM images of the CuO–Ge hybrid film We also present the TEM images of the CuO–Ge hybrid film in Figure 4A. The obtained distributions of Cu and Ge are shown in Figure 4B the energy dispersive spectroscopy mapping profile obviously pictures that the outer sheath consists of Ge whereas Cu is perfectly populated in the inner part of the CuO–Ge hybrid film and the Ge films were grown uniformly and was deposited onto the whole CuO NWs (A) Annual dark-field TEM image of the CuO–Ge hybrid film; (B) elemental mapping of CuO–Ge hybrid film: the corresponding Cu the Coulombic efficiency of the battery was all above 99.2% the first discharge and charge capacities are 3.34 and 2.50 mA h cm−2 for CuO NWs array and 0.71 and 0.59 mA h cm−2 for Ge film The CuO–Ge hybrid film electrode exhibits much higher initial charging areal capacity when compared with the sum of the Ge film and CuO NWs array electrode This is because the mass loading of the Ge film on CuO NWs array is higher than that on CF attribute to the larger surface area of the CuO NWs array demonstrating the structural advantages of the CuO NWs array (A) The initial voltage profiles of the CuO–Ge hybrid film and Ge film; (B) the cycle performance of the CuO–Ge hybrid film and Ge film; (C) the initial five cyclic voltammetry (CV) curves of the CuO–Ge hybrid film; (D) rate performance of CuO–Ge hybrid film Figure 5B compares the cycle performance of the CuO–Ge hybrid film CuO NWs array and Ge film for subsequent 150 cycles at a high current density of 0.8 mA cm−2 For the CuO–Ge synthesized film electrode a reversible discharge capacity of 3.81 mA h cm−2 was achieved at the second cycle corresponding to a specific capacity of 883 mA h g−1 The electrode could still deliver a high areal capacity of ~3.45 mA h cm−2 with a capacity retention of 90.5% after 150 cycles (the corresponding specific capacity contribution from Ge was 1,462 mA h g−1 the CuO NWs array electrode could deliver a capacity of 2.47 mA h cm−2 after 150 cycles which corresponds to the 90.0% of the original one While Ge film can only obtain a reversible capacity of 0.2 mA h cm−2 after 150 cycles with a much lower capacity retention of 59.3% The CuO–Ge hybrid film electrode exhibits a superior improvement in Li storage performance compared to the other electrodes which may be attribute to the novel structure design using a hierarchical 3D nanostructure to combine two high theoretical capacity materials The well-separated CuO NW arrays will not only provide large area for larger mass loading of Ge but also the large void space to overcome the large volume change during charge and discharge The CV curves were well-overlapped with each other from the second cycle afterwards suggesting that the electrode has a good reversibility The rate capability is further tested for the CuO–Ge hybrid film electrode, which is of significant importance for high power energy storage. The rate performance was evaluated by charging–discharging at varied current densities varying from 0.4 to 4 mA cm−2. As shown in Figure 5D after the first five cycles at the current density of 0.4 mA cm−2 the obtained electrode showed a high discharge areal capacity of 3.85 m A h cm−2; then it slightly reduced to 3.68 and 3.45 m A h cm−2 at current rates of 0.8 and 1.6 mA cm−2 Even at a rate as high as 4 mA cm−2 the CuO–Ge hybrid film could still deliver a reversible capacity of ~2.98 m A h cm−2 corresponding to the 77.4% capacity of the capacity at 0.4 mA cm−2 After the rate returned back to the initial value of 0.4 mA cm−2 for five cycles 94.5% of the initial charge capacity was regained and eventually obtained a capacity of 2.59 m A h cm−2 Indicating the benefit from the favorable nanostructures as well as the synergic effect of the Ge film and CuO NWs array the hybrid electrode hybrid film electrode has wonderful rate capability far beyond the CuO NWs and Ge film electrode (A,B) SEM images of the CuO–Ge hybrid film after 50 cycles an efficient strategy to prepare self-supporting electrode with ultrahigh areal capacity for LIB application has been introduced The obtained CuO–Ge hybrid film electrode exhibits excellent lithium storage performance It can deliver a high areal capacity of 3.81 mA h cm−2 after 150 cycles corresponding to 90.5% of the original one the electrode could deliver high areal capacities of 2.98 mA h cm−2 even at ultrahigh current density of 4 mA cm−2 The hierarchical CuO–Ge hybrid film grown directly on CF could be a novel substitute of graphite for LIBs and the facial and efficiency synthesis strategy sheds light on improving the areal capacity of the self-supporting electrodes which can be applicable for preparation of other high capacity hybrid electrode for energy storage application All datasets generated for this study are included in the article/supplementary material All authors have contributed in various degrees to the analytical methods used or to revise it critically for important intellectual content This work was supported by the National Natural Science Foundation of China (grant number 11704071) the Excellent Youth Foundation of Fujian Scientific Committee (grant number 2019J06008) the Natural Science Foundation of Fujian Province and the Award Program for Fujian Minjiang Scholar Professorship Construction of carbon nanoflakes shell on CuO nanowires core as enhanced core/shell arrays anode of lithium ion batteries High capacity Li ion battery anodes using ge nanowires Lithium-ion battery anodes of stacked nanowire laminate for ultrahigh areal capacities CrossRef Full Text | Google Scholar Electrochemical performance of polycrystalline CuO nanowires as anode material for Li ion batteries Copper germanate nanowire/reduced graphene oxide anode materials for high energy lithium-ion batteries In-situ oxidized copper-based hybrid film on carbon cloth as flexible anode for high performance lithium-ion batteries Solution-grown germanium nanowire anodes for lithium-ion batteries Hierarchical structures based on two-dimensional 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This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) *Correspondence: Xinghui Wang, c2VhcGh5MjNAZnp1LmVkdS5jbg==; Shuying Cheng, c3ljaGVuZ0BmenUuZWR1LmNu research in the humanities and social sciences is constrained or even prevented and the people with whom researchers come into contact for their work are sometimes threatened or endangered there are a growing number of exogenous constraints (security political and economic) which place both the right to investigate and the rights of those being investigated in tension: by preventing or restricting access to the research field upstream by putting researchers and their respondents in difficulty and by also exposing them to risks on their return particularly in the restitution and valorization of their work an initial Inalco survey entitled "Research training and expertise in "prevented" or "hindered" fields: practices methods and new resources" was launched in February 2024 Its results are based on the responses of over 400 researchers and young researchers in areal studies They made it possible to objectify knowledge of their research and data collection practices in "impeded" "hindered" or more broadly "constrained" terrains and their expectations in terms of training institutional support and knowledge sharing The first results, published in December 2024 highlight the entrenchment of constraints (political-administrative situational) and their impact on research practices: whether in terms of the conditions (notably financial and institutional) in which it is carried out the environment in which it is embedded (creating new forms of interaction with local partners) or the cross-fertilized methodologies it presupposes The second part of this investigation is now underway, in the form of workshops conducted with the Études aréales unit (UAR 2999) as part of the "Terrains contraints" mission 2024 by CNRS SHS to its aréaux networks in collaboration with Inalco This mission intends to reflect on the best ways to support researchers in their practices and propose concrete recommendations in this area to the entire scientific community aimed at clarifying and completing the results of the survey Locals question police action despite agreement over alternate route for Shiv Jayanti celebrations Residents of Sao Jose de Areal and police come face to face at Benabhat after the cops stopped the tenant from re-erecting his fencing which was damaged on Monday MARGAOTension rent the air at Sao Jose de Areal again on Tuesday evening after the police and other authorities prevented the tenant from re-erecting fencing on his tenanted field at Benabhat despite a solution worked out by the authorities on Monday that visitors to the statue of Shivaji Maharaj would use an alternate access Areal residents rushed to the site in support of the tenant suspecting that the police were stopping the fencing work to pave the way for visitors to go to the Shivaji statue through the tenanted field and Salcete Mamlatdar Vimod Dalal rushed to Benabhat-Areal and villagers also descended at the site and questioned the police and other authorities for obstructing the tenant from completing the fencing work The Velim MLA reminded the police that the authorities and the parties had all agreed on Monday that an alternate access would be used to go to Shivaji’s statue at Benabhat He wondered why the police were preventing the tenant from erecting the barbed wire fencing in his tenanted field raising fears about whether there was any plan to use the tenanted field to go to the statue on Wednesday during Shiv Jayanti celebrations The police team were heard requesting the tenant Cruz Tereza to keep the barbed wire fencing work on hold for a day or two only fuelling suspicions among the locals about whether there was any hidden agenda by the authorities to allow visitors to use the tenanted field to make it to the Shivaji statue on Wednesday to celebrate Shiv Jayanti Velim MLA Cruz Silva told the media that the District Collector Egna Cleetus had later told the police to allow visitors to the Shivaji statue only through the alternate access Collector directs cops to stick to alternate route arrangementMARGAO: South Goa District Collector visited Benabhat in Areal village on Tuesday evening to take stock of the ground situation before directing the police and other authorities to stick to the alternate access for visitors to the statue of Shivaji Maharaj as agreed upon by the parties on Monday After walking to the hilly terrain along with Additional Collector Srinet Kothwale and Velim MLA Cruz Silva from the main road where the statue of Shivaji Maharaj was installed last year the district collector went into a huddle with DySP Sidhant Shirodkar and Salcete Mamlatdar Vimod Dalal to discuss the situation She later told DySP Shirodkar that visitors who wanted to celebrate Shiv Jayanti on Wednesday should take the alternate access to the Shivaji statue She assured the locals that the private property would not be used by the visitors to go to the statue the collector further told DySP Shirodkar to deploy police at the site on Wednesday as a precautionary measure Locals allege developer ‘stoking’ up tension for own gainsMARGAO: Sao Jose de Areal residents on Tuesday said they are neither against the statue of Shivaji Maharaj nor any religion and attributed the root of the tension to the development of plots in the area Saying the people would never hurt the sentiments of anyone who has been trying to develop the orchard land into plots since 2012 has stoked the controversy by giving a portion of this land to install the Shivaji statue last year hoping it would provide road access to his developed plots Peter Viegas told the media that for 10 years the land developer Mehboob Makandkar has been trying to develop plots at Benabhat has no access to his property due to the fields between his property and the main road Tenant Milages Tereza told the media that he had issued an NOC to a party over a year ago to carry material to his tenanted field through misrepresentation “The party had asked for an NOC to allow him to take material to his property He misused the NOC to put the statue of Shivaji Maharaj We are not against Shivaji Maharaj or any religion,” he added.