Volume 12 - 2018 | https://doi.org/10.3389/fnsys.2018.00055 This article is part of the Research TopicBrain States and Neural ComputationsView all 12 articles Neural circuits are able to perform computations under very diverse conditions and requirements The required computations impose clear constraints on their fine-tuning: a rapid and maximally informative response to stimuli in general requires decorrelated baseline neural activity Such network dynamics is known as asynchronous-irregular spatio-temporal integration of information requires maintenance and transfer of stimulus information over extended time periods or even combine the above properties in a task-dependent manner would present a clear functional advantage We propose that cortex operates in a “reverberating regime” because it is particularly favorable for ready adaptation of computational properties to context and task This reverberating regime enables cortical networks to interpolate between the asynchronous-irregular and the critical state by small changes in effective synaptic strength or excitation-inhibition ratio These changes directly adapt computational properties integration time and correlation length within the local network We review recent converging evidence that cortex in vivo operates in the reverberating regime and that various cortical areas have adapted their integration times to processing requirements we propose that neuromodulation enables a fine-tuning of the network so that local circuits can either decorrelate or integrate and quench or maintain their input depending on task which we call “dynamic adaptive computation,” presents a central organization principle of cortical networks and discuss first experimental evidence (C) Dynamic adaptation of collective dynamics in local circuits the whole field of view needs to be presented equally in cortex This could be realized by local adaptation of the network dynamics which amplifies the inputs from the receptive fields representing the rabbit (“tuning in”) while quenching others (“tuning out”) While a phase transition can be very useful to realize cognitive state changes we here want to emphasize a particular property of systems close to phase transitions: without actually crossing the critical point already small parameter changes can have a large impact on the network dynamics and function Hence a classical phase transition may not be necessary for adaptation In addition to the well-established phase transitions adaptation could be realized as a dynamic process that regulates the proximity to a phase transition and allows cortical networks to fine-tune their sensitivity and integration timescale within one cognitive state cortical networks must evidently satisfy the following requirements (i) The network properties are easily tunable to changing requirements the required synaptic or neural changes should be small (ii) The network is fully functional in its ground state the adaptive tuning does not destabilize or dysfunctionalize it modifies and transfers information according to its needs it amplifies or quenches the input depending on task (iv) The network's ground state in general should enable integration of input over any specific past window we recapitulate the computational properties of these two states and then identify recent converging evidence that in fact the reverberating regime governs cortical dynamics in vivo We then show how specifically the reverberating regime can combine the computational properties of the two extreme states while maintaining stability and thereby satisfies all requirements for cortical network function postulated above we outline future theoretical challenges and experimental predictions can be interpreted as the two extreme points on a continuous spectrum of response properties to minimal perturbations the first quenching any rate perturbation quickly within milliseconds Hence the two hypotheses clearly differ already in the basic response properties they imply Hence the principle of dynamic adaptive computation detailed below can be implemented and exploited in very diverse types of neural networks The neural efficacy m determines the average impact any spike has on the network network dynamics can range from irregular (m = 0) to critical (m = 1) and unstable (m > 1) dynamics the “reverberating regime” (green) observed for cortex in vivo is well visible It has clearly a larger m than the irregular state (blue) but maintains a safety margin to criticality (yellow) and the instability associated with the supercritical regime (red in B,C) (B,C) Sketch to illustrate the divergence of dynamical and computational properties at a critical phase transition at the example of the network timescale and the sensitivity (B) The network timescale determines how long input is maintained in the network While any rate change is rapidly quenched close to the irregular state (m = 0) input “reverberates” in the network activity for increasingly long timescales when approaching criticality (m = 1) the network timescale is tens to hundreds of milliseconds implying instability (assuming a supercritical Hopf bifurcation here for illustration) The reverberating regime keeps a sufficient safety margin from this instability (C) The reverberating regime found in vivo allows large tuning of the sensitivity by small changes of the neural efficacies (e.g. synaptic strength or excitation-inhibition balance) in contrast to states further away from criticality (insets) We will show that this reverberating regime with median m = 0.98 (0.9 < m < 0.995) observed in vivo is optimal in preparing cortical networks for flexible adaptation to a given task and meets all the requirements for dynamic adaptive computation we postulated above If these fluctuations are not strongly correlated across synapses the variance of the single neuron efficacy mi≈kw̄ scales with the number k of outgoing synapses σmi2≈kσw2 and gives The resulting margin from criticality is compatible with the m observed in vivo These networks show transient instability (i.e. m(t) > 1) until inhibition stabilizes the activity large changes in m(t) on a millisecond scale should be considered a “state” is an open question experimentally a time resolved m(t) can be estimated with high temporal resolution This measurement could then give insight into the state changes required for computation network fine-tuning most likely is not based on optimizing one single network response property alone but represents a trade-off between desirable and detrimental aspects This tradeoff can be represented in the most simple case by a goal function which weighs the desired (Φ+) and detrimental (Φ−) aspects by a task dependent weight factor α, and might be called free energy in the sense of Friston (2010) the desired and detrimental aspects diverge and depend on the critical scaling exponents β+ and β− the normalization constants of Φ+ and Φ− are taken into account by the rescaled weight α′ Maximizing the goal function then yields an optimal neural efficacy m* This optimal neural efficacy (i) is in a subcritical regime unless α = 0 (i.e. detrimental aspects do not matter) and (ii) depends on the weight α′ and the exponents β+ and β− In the simplified picture of branching processes the resulting m* determines a large set of response properties which can thus only be varied simultaneously An “ideal” network should combine the capability of dynamic adaptive computation with the ability to tune many response properties independently To which extent such a network is conceivable at all and how it would have to be designed is an open question we extend on this concept and propose that cortical networks not only rely on reverberations but specifically harness the reverberating regime in order to change their computational properties Relating these changes to specific functional task requirements remains a theoretical and experimental challenge for the future All authors were involved in the conception and revision of this study and VP calculated the presented derivations All authors received support from the Max-Planck-Society JZ and VP received financial support from the German Ministry of Education and Research (BMBF) via the Bernstein Center for Computational Neuroscience (BCCN) Göttingen under Grant No JW was financially supported by Gertrud-Reemtsma-Stiftung JP received financial support from the Brazilian National Council for Scientific and Technological Development (CNPq) under grant 206891/2014-8 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 Figure 1C was partly derived under CC BY-SA 4.0 license Is the rostro-caudal axis of the frontal lobe hierarchical Information flow in a kinetic ising model peaks in the disordered phase Neuronal avalanches in neocortical circuits Being critical of 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COVID-19 Funeral Assistance – FEMA is now helping those that have lost a loved one from COVID-19. Click HERE to review the information on eligibility and requirements on the COVID-19 Funeral Beloved wife for 41 years of Fred Voegtli; loving and devoted mother of Jami (Jon) Zierenberg Jonathan Voegtli (fiancée) Melissa Gomez Mendez) Kristina (Nick) Tsoubanos and stepmother of Joshua (Amy) Voegtli; adoring grandmother of Alec and Kaili Martin Connor and Jenna Voegtli and Franco Solano; cherished daughter of Vivienne (Frank) Bergmann and Neal Muren; dear sister of Pamela (the late Bill) Mauser Cindy was an avid and extremely talented quilter gardener and crafter who was loved by all that were lucky to know her Our dearest Cindy showered others with love by preparing them high-quality delicious meals or gifting her one-of-a-kind handmade quilts She found great joy in simply spending time with her family and beloved dog (and granddogs!) cultivating her garden or peacefully quilting a masterpiece Cindy will be deeply missed but with us always; may her memory be eternal Services: Visitation at Kutis South County Chapel (5255 Lemay Ferry Road) on Thursday from 4:00-7:00 PM; a ceremony at Kutis South County Chapel at 12:30pm on Friday then taken to Jefferson Barracks National Cemetery at 1:45pm Funeral Service Live Stream My deepest sympathy to Cindy’s loving family I’m very sorry for your loss sending Love and Prayers to your family during this time 🙏💟 Lynette King and I were friends in high school My condolences and blessings to her family and friends She was and will always be such a beautiful spirit And I know she leaves a legacy of love all around her My deepest sympathy goes out to the family Jami & Jon so sorry for your loss you will be in my thoughts and prays and I had behind the wheel in high school with the football coach He always said God had special place in heaven for him because of driving with us on game day Cindy always had something clever to say when I was driving I’ll always cherish the sweet swaddling cloths Kristina had her make for my baby Vera May God wrap her family in His arms and watch over them closely Cindy and I worked together at MetLife and although we never met in person (she was in St She was so knowledgeable about many work things and always ready to share that knowledge But our biggest bond was through sewing and we had many talks about quilting and sewing She sewed so perfectly and had a great talent Δdocument.getElementById( "ak_js_1" ).setAttribute( "value" For personalized and affordable funeral arrangements choose Kutis Funeral Home - a family-owned establishment serving St 2906 Gravois Avenue, St. Louis, MO 63118314-772-3000 10151 Gravois Road, St. Louis, MO 63123314-842-4458 5255 Lemay Ferry Road, Mehlville, MO 63129314-894-4500 Thames Valley Council for Community Action is turning to a new method of fundraising as it hosts its first virtual 12-mile race to raise needed funds for its Meals on Wheels program Dubbed "Miles for Meals Virtual Race," the event is open to members of the community who can walk bike or swim the dozen miles to participate Proceeds from the event which will be raised through a registration fee and fundraising will go toward providing healthy meals to homebound seniors in the agency’s 1,200-mile coverage area senior director of marketing and development for TVCCA TVCCA provides 180,000 meals - close to 700 meals per day along with wellness checks - to seniors who are often unable to cook don’t have someone who can care for them or whose family members live far away our meal delivery drivers are the only person they see for the entire day," Brown said "Our goal really is to make sure that our most vulnerable population - the grandparents that took care of us - are not forgotten." Meals on Wheels is partially funded by federal and state funds through the Senior Resources Agency on Aging and the Older American Act Money is raised through donations and fundraisers like the annual Carnevale Gala at Mohegan Sun but additional funds are still needed to support the program which is prepared at a commissary in Bozrah only $4.27 per meal is reimbursed with federal and state monies and the remainder is the responsibility of TVCCA registered Monday for the virtual race which she said will help keep herself accountable for her nearly three-mile jogs every other day while also allowing her to contribute to a needed service in the community "Any race that’s for a good cause I like to participate in," she said While her in-laws died before they could take advantage of the Meals on Wheels program Zierenberg said it would have helped them greatly while they were alive because it was sometimes difficult for them to afford the groceries they needed "I think it would have done them a world of good," she said Where: To register and learn more about the Miles for Meals Virtual Race, visit http://bit.ly/MilesforMeals When: Registration began Monday and is ongoing How: Register and fundraise online. Complete your miles and log them by syncing your Fitbit, downloading the Charity Footprints app or keeping track of them manually. Sponsorship opportunities are also available. For more information, contact Megan Brown at (860) 425-6514 or email megan.brown@tvcca.org which is enough to provide meals to a senior for one week Participants who raise the fundraising goal of $160 will be providing meals for one month Participants who raise at least $100 will receive a free gift Please enable JS and disable any ad blocker She was born 10/27/1919 to Edward Zierenberg and Salora Church Zierenberg as her ancestors came over from England on the Mayflower She was an active member of Disciples of Christ churches in Fairbury and Lincoln She and her sister Deane rode to school in a horse drawn carriage She graduated from Fairbury high school in 1938 and worked for the Fairbury Creamery She married Orvil Priefert in 1942 when he was in the Air Force Following the death of her husband in 1963 she moved to Fairbury and worked as a Clerk at the Fairbury City Offices She also trimmed dogs and was once described as a “dog whisperer” she continued to have a dog trimming business her loyal customers from Fairbury brought their dogs to her house in Lincoln Mary and Tom; son-in-law Wes Dowell; daughter–in-law Deanna Priefert; grandchildren Sharon Priefert Valparaiso; and great granddaughter Salora Huff Lincoln; and several beloved nieces and nephews Memorials to Southview Disciples of Christ church sign up for email or text message notifications We respect your privacy. The data gathered will only be used for official Roper & Sons correspondence. For more information see our privacy policy We understand that grieving doesn’t end after the service We offer Aftercare for grief support as you process and heal from your loss Metrics details A common approach to study nucleation rates is the estimation of free-energy barriers This usually requires knowledge about the shape of the forming droplet a task that becomes notoriously difficult in macromolecular setups starting with a proper definition of the cluster boundary Here we demonstrate a shape-free determination of the free energy for temperature-driven cluster formation in particle as well as polymer systems Combined with rigorous results on equilibrium droplet formation this allows for a well-defined finite-size scaling analysis of the effective interfacial free energy at a fixed density We first verify the theoretical predictions for the formation of a liquid droplet in a supersaturated particle gas by generalized-ensemble Monte Carlo simulations of a Lennard-Jones system we then generalize this approach to cluster formation in a dilute polymer solution Our results suggest an analogy with particle condensation when the macromolecules are interpreted as extended particles exploiting a thorough understanding of the underlying phenomenon in a clever way the problem can be reduced to conformational phase space knowing that canonical expectation values typically do not depend on the kinetic energy we analyse a two-dimensional free-energy landscape and identify the energy as a suitable reaction coordinate This allows us to formulate the problem in the microcanonical ensemble of either fixed total energy E or fixed potential energy Ep The first is the usual textbook definition while the latter has been frequently applied in recent computer simulation studies This enables us to directly discuss the effect of kinetic energy when changing between the two formulations E↔Ep only the first one allows a direct physical interpretation the energy-dominated inhomogeneous condensed phase coexists with the entropy-dominated homogeneous gas phase A transition between both phases may only occur by energy variation upon nucleation or dissolution this of course refers to the total energy E For systems where the momentum phase space may be integrated out explicitly (see Methods section) the problem simplifies in terms of computability We hence begin with an illustration in the potential energy formulation (denoted by a hat ) as a direct result of computer simulations before we go over to comparing both energy approaches (a) Illustration of the free-energy landscape (colour map) as a function of potential energy Ep and droplet size ND for N=512 Lennard-Jones particles The minimal free-energy path (black solid line) connects a droplet (Ep≈) and a gaseous (Ep≈) phase (b) The projection onto the reaction coordinate Ep yields the canonical potential energy probability distribution where the free-energy barrier is encoded in the ratio between maximum and minimum at is the (equal) area size enclosed between the microcanonical inverse temperature and the accordingly defined transition temperature The analogous quantities are re-evaluated as a function of total energy E in panels (d,e) with βeqa=βeqh=1.71999(3) We notice that the energy probability distributions Pβ(E) and are related by a convolution involving the Maxwell–Boltzmann distribution PMB(x) as (E) (see Methods section) This in turn corresponds to a physical smoothing which diminishes the ratio between maxima and minimum we expect a lower barrier in the total energy formulation due to the kinetic contribution Illustration of a cluster or aggregate of polymers in a dilute solution (N=64 bead-spring polymers with 13 monomers each; monomer density ρ=10−2) The snapshot stems from the droplet phase (Ep≈) The physical origin are translational invariance as well as capillary waves at the interface Altogether we use for our final scaling ansatz This is the leading-order exponent in equation (1) we obtain from equation (3) to leading order the rate of equilibrium droplet formation as R∝ Thus for increasing system size the probability that a single macroscopic droplet forms decreases exponentially Free-energy barriers (reaction coordinate Ep) and βΔF (reaction coordinate E) of droplet formation in a particle gas (a) and dilute polymer solution (b) as a function of the number of constituents N The leading N1/2 scaling is clearly demonstrated The insets show the finite-size scaling of the interfacial free energy according to equation (3) making quantitative predictions for the polymer case less reliable the overall behaviour supports the hypothesis that cluster formation in a dilute polymer solution shows a strong analogy to droplet formation in a particle gas We observe that considering the kinetic contribution results in a shifted barrier For the considered examples and relevant system sizes while much smaller than the leading behaviour leads to a multiplicative relation between the nucleation rates R∝e−βΔF≈∝3 Neglecting the momentum phase space thus underestimates the rates the deviations between experiment and simulations are of the order of several magnitudes such that the effect of the kinetic contribution may be considered subleading Inverse transition temperature (reaction coordinate Ep) and βeqa (reaction coordinate E) of droplet formation in a particle gas (a) and dilute polymer solution (b) as a function of the number of constituents N The finite-size scaling ansatz of equation (4) describes the data perfectly The inset shows a vanishing finite-size difference between both ensembles ∝N−3/4 for cluster formation in both particle gas and polymer solution least-square fits for Nmin=192 yield β0=1.436(2) and each with Q≈0.5 The excellent fit results show that the empirical higher-order corrections describe the finite-size scaling very well the strong finite-size deviations open a possibility to study finite-size scaling in experiments on the nanoscale (for a conversion The finite-size transition temperature of the largest system (N=2,048) is which still deviates from the thermodynamic limit by (10%) which manifests in the geometric differences of the microcanonical inverse temperature and the enclosed areas in equation (2) It appears that correlations between the ensemble definitions account for compatible leading-order scaling corrections in equation (4) which further supports this ansatz and explains the observed difference For polymer aggregation in Fig. 4b fits of equation (4) yield β0=0.64(2) and for Nmin=14 (guided by the inset) each with Q≈0.8 the fit ansatz describes the data already well when including the smallest system sizes Also the finite-size ensemble deviation in the inset shows a clear N−3/4 trend for N≥14 this is an indication for the analogy between cluster formation in polymer solutions and droplet formation in a particle gas We have presented a shape-free approach to the estimation of canonical free-energy barriers in equilibrium droplet formation The finite-size scaling is dominated by the predicted N1/2 behaviour but we identified additional logarithmic corrections from precise numerical estimates the absolute free-energy barrier is sensitive to the consideration of the kinetic contribution It is well known that the restriction to the conformational phase space does not influence finite-size transition points determined from canonical expectation values These are evaluated on the level of the canonical partition function The free-energy barrier and the associated equal-height or equal-area transition temperature are determined from the energy probability distribution Here the two formulations are related by a convolution with the Maxwell–Boltzmann distribution which explains the finite-size differences the probability distributions are the integrands of the respective partition functions this boils down to the trivial fact that equality of integrals does not imply equality of the integrands This may become relevant once theoretical predictions and experimental measurements become precise enough a restriction to the conformational phase space retains intensive parameters in the thermodynamic limit considering the total energy as reaction coordinate leads to less fluctuations in the microcanonical partition function and canonical probability distribution since the underlying convolution is a smoothing procedure of physical origin We provided evidence that the derived finite-size scaling of canonical droplet formation is applicable to cluster formation in dilute polymer solutions as well despite the a priori non-trivial shape of the polymer cluster This is a clear indication of an analogy between particle condensation and polymer aggregation we showed that polymer clusters are in equilibrium with non-attached (free) polymers: an inhomogeneous or mixed phase of aggregate and solute polymers This is intuitively clear when the polymers are interpreted as extended particles The leading-order corrections then follow from the interplay between energy minimization by forming a local cluster and entropy maximization by retaining freely movable constituents additional corrections should follow from the explicit geometry and internal behaviour of the constituents simulations may provide reliable estimates for finite-size systems and meet experiments on the nanometer scale This is a crucial aspect relevant for physical interpretations that appears to be unwittingly softened in the past decade The microcanonical ensemble (NVE) describes an isolated system in which the number of constituents N the volume V and the total energy E are conserved Here the transfer of potential energy Ep into kinetic energy Ek and vice versa is a valid and relevant mechanism The microcanonical (Boltzmann) entropy is defined as S(E)=kB ln Γ(E) where denotes the integration over state space and over momentum space we determine the microcanonical inverse temperatures as follows In the conformational microcanonical ensemble we have direct access to an estimate of ln Ω(Ep) (see below) such that (Ep) is obtained by a numerical five-point derivative we may estimate the inverse temperature in terms of microcanonical expectation values for N independent particles where the explicit prefactor in equation (5) cancels The canonical ensemble is defined in terms of the partition function where each phase-space point is weighted with the Boltzmann factor according to the total energy the kinetic part may be explicitly integrated for generic systems Each degree of freedom contributes with a Gaussian integral where is the partition function of the conformational canonical ensemble Both partition functions may be expressed as integrals in terms of the respective energies The corresponding canonical energy probability distributions are defined as Pβ(E)=Γ(E)e−βE/Zβ and We may now relate the two energy probability distributions by starting with the definition of Pβ(E) and inserting equations 5 and 7: We identify the latter part of the integrand as the N-particle Maxwell–Boltzmann distribution PMB(x) and may write equation (8) as a convolution a system with 2,048 particles requires a box of linear dimension L′≈59 =59 × 21/6 σ′ σ′≈3.4 Å such that L′≈22.5 nm is on the nanoscale for a comparison to an experimental setup one should include both the explicit geometric constraints and the full Lennard-Jones potential The data that support the findings of this study are available from the corresponding author upon request The computer code required to generate the data as well as the analysis scripts that lead to our conclusions are available from the corresponding author upon reasonable request Canonical free-energy barrier of particle and polymer cluster formation Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations Homogeneous nucleation and growth of droplets in vapours 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transitions Microcanonical phase diagrams of short-range ferromagnets Microcanonical entropy inflection points: key to systematic understanding of transitions in finite systems Disorder and Criticality: advanced Problems of Phase Transition Theory Vol Thermodynamics and structure of macromolecules from flat-histogram Monte Carlo simulations Statistical thermodynamics of the cluster solid-liquid transition Phase changes in 38-atom Lennard-Jones clusters A parallel tempering study of equilibrium and dynamic properties in the molecular dynamics and microcanonical ensembles Consistent thermostatistics forbids negative absolute temperatures Overcoming timescale and finite-size limitations to compute nucleation rates from small scale well tempered metadynamics simulations Multicanonical algorithms for first order phase transitions Multicanonical ensemble: a new approach to simulate first-order phase transitions Multicanonical simulation of the two-dimensional 7-state Potts model Scaling properties of a parallel implementation of the multicanonical algorithm Application of the parallel multicanonical method to lattice gas condensation the Bootstrap and Other Resampling Plans Society for Industrial and Applied Mathematics (1982) Everything You Wanted to Know About Data Analysis and Fitting but Were Afraid to Ask Springer Briefs in Physics Springer International Publishing (2015) Download references The project was funded by the European Union the Free State of Saxony and the Deutsche Forschungsgemeinschaft (DFG) under Grant No JA 483/31-1 and Sonderforschungsbereich/Transregio SFB/TRR 102 (Project B04) We gratefully acknowledge the computing time provided by the John von Neumann Institute for Computing (NIC) on the supercomputer JURECA at Jülich Supercomputing Centre (JSC) under Grant No Part of this work has been financially supported by the Leipzig Graduate School of Natural Sciences ‘BuildMoNa’ and by the Deutsch-Französische Hochschule (DFH-UFA) through the Doctoral College ‘’ under Grant No All authors contributed equally to the theory and J.Z All authors discussed the results and commented on the manuscript The authors declare no competing financial interests Download citation 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 Jennifer Lawrence and Wareham’s Charlie Tacker all stepped in front of the camera for the upcoming ‘you look like Batman,’ and [Bale] looked down at me She said Tacker had no idea he was standing next to Batman at first because Bale was so dressed up Charlie did not know who he was,” said Zierenberg “He was in disguise… he had this beard,” Tacker replied “I could see Christain Bale patting Charlie on the shoulder,” Zierenberg explained ‘why does Batman keep hitting you on the shoulder?’ And he goes what are you talking about?’ I said that was Christian Bale.” Tacker told the bearded man he looked like Batman This was not the only movie star Tacker interacted with and these two kids came up to me and told me to say “I almost hit Jennifer Lawrence in the face with a notebook,” admitted Tacker she did not notice the potential collision I’m sure he’s going to be in this film,” said Zierenberg The film cameras were not the only cameras having Charlie in the frame “Channel 7 came to get shots of the shooting and they got a shot Christian Bale talking to a kid – it was Charlie and Charlie was doing the Dougie in background.” Tacker has far more acting experience than most 10-year-olds student films which has earned Tacker the nickname: “Prince of the Indies.” This has been accomplished with the help of the New England Acting and casting community Tacker is usually given more demanding roles “Advent,” a film about aliens coming to earth gave him an opportunity to be in an action situation Being in indie films and feature films “is not that much different and the student films will take – maybe a couple of days -- like ten days,” Tacker explained “The one feature film I’ve been in took like a month.” Despite the time demands of being an actor Tacker does also go through the typical life of a kid in Wareham he is attending Wareham Middle School as a 5th grader Tacker was among the group moved from Decas Elementary to the Middle School This has been an adjustment for Tacker and his mom “It’s a whole other world,” said Zierenberg Attendance could have made the adjustment even harder acting has taken Tacker away from school for just five days this year the pressure can sometimes build on Tacker Tacker looks forward to playing in the snow I think I’m just a normal kid in Wareham,” said Tacker I will be riding a private jet to Disney.” Nine-year-old actor Charlie Tacker of Wareham is a budding actor on the Boston scene and already has an impressive resume for such a young guy Charlie got his start at 4-years-old as an extra on the Ben Affleck directed movie "The Town," and has worked on the as yet unnamed Christian Bale movie currently being shot in Massachusetts he was in the Steve Carell film "The Way Way Back," which shot scenes in Wareham If Charlie keeps chugging along at the pace he is and he's pretty specific about how he'll be spending his time by that point: "In a penthouse with a waterbed and a closet full of Jordans [Nike sneakers] While he's worked with some great actors Charlie's original inspiration is one that is near and dear to the hearts of little boys and comic book nerds of any gender I watched a lot of super hero movies and fiction movies and then I'm like 'I wanna be Spiderman!'" After emulating Peter Parker's post irradiated spider bite persona Charlie's mom thought it would be prudent to show him just how the magic of movies made Spiderman's high flying adventures possible "[Since] my mom doesn't want me to jump off cliffs and stuff she  made me watch green screen footage and stuff and I was like 'I wanna do that.'" the bulk of his work has been on student and independent films for which he doesn't need an Screen Actor's Guild (SAG) card Charlie says he wouldn't want to move to New York or Los Angeles and leave his friends in Massachusetts Decas Elementary School are very supportive of him "The administration at Decas is amazing," says Zierenberg and they are all so supportive of his career and they know that his education is important to me and they do whatever they can He's currently working on the independent feature film "Firefly Jar," a movie about a boy coping with the loss of his mother Charlie has dealt with a number of roles that involve things he's never had to deal with in real life One of those films is "Young Man," for which he was runner up for best actor at the Boston 48 Hour Film Project in 2012 "It's about this little boy and his mom is really sick so he starts taking care of her He really wants to grow up,"  explains Charlie Charlie doesn't mind taking on such roles and watching clips of his films makes it apparent that he's more than capable of handling them expressive eyes generate powerful emotion in a way that can't be taught and sometimes it doesn't really turn out perfect," Charlie explains Charlie says he's more of a "comedy guy," and hopes some comedic roles come his way soon he exercises his comedic muscles by pranking his co-stars on set Charlie was working with Artie Wahlberg (Yes Mark's brother) on the set of the film "The Lady in White," and decided things were getting a little too serious noting that he pretended to drop the bottle's cap Artie can you get that?' and he was like 'Oh sure.' On my phone I have a fart app I pressed the phone and everyone's like If you'd like to check out Charlie's lead role in "I Fell Silent," it will be premiering at the Bright Family Screening Room at Emerson College's Paramount Theater The film was directed by Emerson students Carson Lund and Michael Basta Click here to learn more about Charlie on his Facebook page Editor's Note: This article is part of an occasional LiveScience series about ideas to ease humanity's impact on the environment The world's greatest source of power lies a few miles under our feet which draws on the heat from the Earth's interior could supply the current global energy demand for more than 30,000 years Geothermal energy accounts for less than a half-percent of global energy consumption according to the International Energy Association Most of the active geothermal plants are located in volcanically active places "Conventional geothermal has limited use because the required geology is not found everywhere," said geophysicist Roy Baria of the company Mil-Tech UK LTD Baria and others are engineering non-conventional places where the heat is farther down and there is no room for water to flow These geological enhancements can have their drawbacks: One project in Switzerland was shut down earlier this year due to induced earthquakes Get the world’s most fascinating discoveries delivered straight to your inbox A typical geothermal plant captures steam escaping from underground and uses it to turn turbine blades that generate electricity The first such power plant began in Italy in 1904 and continues to work to this day geothermal does raise environmental concerns the amount of CO2 released per kilowatt-hour of electricity is only a few percent that of coal-fired power plants Although it supplies power more consistently than the fickle wind and daily setting sun geothermal energy is not entirely renewable The largest geothermal development in the world actually began to decline because it essentially ran out of steam "It was overproduced," said Robert Zierenberg a geologist at the University of California thanks to the underground injections of imported wastewater With the fear or depleting natural resources environmentalists have fought the development of other geothermal projects in places like Hawaii and Yellowstone "Iceland is an ideal case for geothermal because it is a volcanic island with no natural fossil fuel reserves," said Peter Schiffman Geothermal plants supply approximately a quarter of Iceland's electric power and leftover heat is used to warm homes and greenhouses "The Icelanders have taken as much as they can from their geothermal resource," Zierenberg told LiveScience Zierenberg and Schiffman are part of the Iceland Deep Drilling Project (IDDP) which hopes to increase the normal 5 megawatt power output of a geothermal plant by a factor of 10 This will require digging into the hottest rock ever utilized Typical geothermal power plants tap into steam from underground fissures where the temperature is roughly 400 degrees Fahrenheit (200 degrees Celsius) By drilling 3 miles down in a selected spot IDDP will reach temperatures of 840 degrees Fahrenheit (450 degrees Celsius) water is in a strange liquid-gas phase called supercritical which carries 10 times more energy than steam The challenge will be divining where this supercritical water is Fluid can only flow in rocks that are fractured so IDDP has chosen a site where seismic activity is high "We look near earthquake areas because that is where cracking is occurring," Zierenberg said geo-engineers are generating their own tiny earthquakes to make hot dry rock amenable to geothermal energy these projects require drilling a well a few miles down and pumping water in at high pressure This induces small seismic events that fracture the rock and provide a route for water to flow A second well is then drilled to bring the boiled water to the surface the typical size of the seismic events would not even register on the Richter scale high-pressure water pumping at a Swiss EGS site last December induced four earthquakes in Basel ranging from 3.1 to 3.4 on the Richter scale "That project should not have been started there," Baria said because Basel has a history of earthquakes including one that destroyed the city in 1356 "We advised that it was not a good place." Local authorities in Basel have postponed the project while a review is being performed The biggest hurdle is the cost of drilling which will generally need to be at least 3 miles down Baria expects the average EGS power plant to cost $20 million to $30 million and to last 20 to 25 years Zierenberg doubted that the United States is ready for that kind of large-scale development They're more willing to embrace geothermal energy because they can see their glaciers melting," Zierenberg said Hårby Valkyrie: A 1,200-year-old gold Viking Age woman sporting a sword May's full 'Flower Moon' will be a micromoon (CNS): The teenager hit by a minivan on the West Bay Road Monday night remains in a serious condition at the George Town hospital Media reports in the US have named the young man as Harrison Zierenberg from Midlothian in Virginia who was on a spring-break vacation with his parents Described by friends and coaches as an active athlete who plays varsity lacrosse Zierenberg is a sophomore student at James River High The driver of the mini-van that hit the young man as he was crossing the road in front of the Marriott Resort remained in custody yesterday after he was arrested for dangerous driving but has not yet been charged Many commenters who posted on CNS Tuesday about the news of the teenager being knocked down pointed to the poor lighting in what is a very busy area for cars and pedestrians alike and called on officials to address the problem Area where US visitor Harrison Zierenberg was knocked down on Sunday 5 April 2015 Tags: Category: Crime, Police Trackback URL | Comments RSS Feed If the family of this young man are reading these comments I urge you(as a local) to get your son out of that hospital as quickly as possible The HSA’s track record speaks for itself praying for his family and praying that God uses the doctors in his name and glory to heal this young man Lets call a spade a spade.There are way to many IDIOTS speeding on Wbay road.Where is the new speed limit law?This is where many of our visitors stay and more must done to keep everyone safe.More traffic calming needs to be implemented ASAP and the lighting situation needs to be addressed.Hopefully this young man will survive and be able to resume his normal life I would suggest to the family to air ambulance this child out of Cayman….no more needs to be said It is simply not possible to just air ambulance someone unless they are stable and fit enough An air ambulance is not a critical care unit Hey moron I never said I was an online doctor but the care he is receiving at George Town Hospital is what we compare to third world country care At least send him to Shetty or Chrissie Tomlinson until he is ready to be air ambulanced out Never did I say air ambulance was a critical care unit but his odds will be more in his favour leaving GT Hospital!! Comment * document.getElementById("comment").setAttribute( "id" "ad27885cabd776af15ab622ca4c75217" );document.getElementById("f6c5908192").setAttribute( "id" This site uses Akismet to reduce spam. Learn how your comment data is processed. Cayman News Service (CNS): A 17-year-old boy from Virginia who was struck by a local bus when he was crossing the West Bay Road last month is on the mend his mother has told the local media in his home state Harrison Zierenberg is now able to talk but he is still suffering the effects of brain damage and cannot yet walk His mother said the young man was struck in the head by the van’s wing mirror as it sped along the road Police arrested the 56-year-old driver of the bus at the time of the incident but no charges have yet been brought in the case CNS has contacted the RCIPS to establish the state of the investigation and is awaiting a response who has been in hospital in Miami for several weeks after emergency surgery here in Cayman has a plate in his head but his mother said her son’s progress has been miraculous considering that he suffered life-threatening head trauma He was due to be moved Thursday to a local hospital where will undergo further surgery and start the extensive therapy to help him walk again According to The Richmond Times Zierenberg who lost his father to a road accident is expected to eventually get back on his feet because despite almost losing his life the teenager did not suffer any lasting spinal damage that he was hit by a car going at least 50 mph … His spine is perfect,” Lee Ann Zierenberg said The family was on vacation when Zierenberg was hit by the bus around 9pm on 6 April close to the Marriott hotel Government was expected to formally reduce the speed limit on the West Bay Road this month but as yet the change has not been implemented Trackback URL | Comments RSS Feed There is no functional law enforcement on Grand Cayman A study should be conducted to see just how dangerous some people will drive when there is no penalties to do so The over takers from east end and north side early in the mourning have got to be the worst In the last month I have seen them over take many cars at the same time and force the drivers coming from Bodden town off the road 3 times so far I’m just glad I am going in the same direction as they are What they do in there own country they practice here and get away with if They should not be allowed to drive for reward Although it sounds like it will be a long battle These bus drivers get away with EVERYTHING! They are by far the worst drivers on the road from cutting through gas stations to dodge red light they have it all covered and yet you never see any get pulled over As you can see I hate the b*stards with a passion "af722645fe4841b063365f7da75d3e38" );document.getElementById("f6c5908192").setAttribute( "id" NRA staff work on new crosswalk on West Bay Road (CNS): Workers from the National Roads Authority were in the process of erecting a new crosswalk outside the Marriott Hotel Tuesday at one of Grand Cayman’s road black spots The new West Bay Road crossing comes ahead of a much-anticipated speed reduction on that road in a few weeks The area has been the scene of a number of crashes and most recently a teenage visitor narrowly escaped with his life when he was hit by a local bus as he tried to cross the road Harrison Zierenberg (17) from Virginia was on holiday here with his family when he was struck in the head by the wing mirror of the bus in April and suffered brain damage he is understood to be making considerable progress and has been returned to his home state and local hospital Tags: , Category: development, Local News Trackback URL | Comments RSS Feed having a cross walk (that not everyone will use but it’s a start) will help but the lighting is SO awful that accidents will continue to happen The problem will then be getting people to use them So often I see people attempting to cross the road within 50 feet of the crosswalk Dogs on this island however are smarter than people when crossing traffic I think it would be helpful if they posted a “look right” or “look left” with arrows on the sidewalk for tourists at major crossing points as a reminder which way traffic will be coming at them from What about a sign that says look “right and look left” at every crosswalk As pretty as these yellow lines and lovely flashing lights are they’re absolutely pointless until they put an island in the middle lane to stop all the idiots using it to overtake We’ve tried that – it doesn’t work Eventually someone plows through the whole thing I have seen buses on West Bay Road overtake by moving out across the middle lane into the oncoming traffic lane Just a matter of time until some poor soul is mown down by a drunk idiot in a truck or SUV driving back to West Bay I drove through the area (thursday morning) just before reading this Signage warning drivers of NEW crosswalk are really needed Agreed but we are still waiting for the signage for the Waterfront Centre crossing Guess someone will have to die there before that appears When on earth will they drop the speed limit on West Bay Road … soon come I suppose "a0ff8d452d3912981446a01b3a05cc54" );document.getElementById("f6c5908192").setAttribute( "id" (CNS): A 16-year-old boy who was knocked down outside the Marriott hotel while visiting the Cayman Islands on spring break earlier this year has been discharged from hospital and returned home The teenager remains in a wheelchair after receiving life threatening head injuries when he was hit by a local minibus on the West Bay Road in April but is making a slow recovery Police have confirmed that the 56-year-old driver arrested for dangerous driving at the time has not been charged and the case is still pending A spokesperson for the RCIPS confirmed Monday that the man has not been charged but the file is still under review with the legal department Harrison Zierenberg, who is now 17, returned to his home, in Midlothian, Virginia, this weekend, according to the local press which reported that the house has been remodelled to accommodate his wheelchair walk and speak after a large chunk of his skull was removed as a result of the collision when he was struck in the head by the wing mirror of the bus as it sped by him as he was trying to cross the road Category: Crime, Police, USA, World News Trackback URL | Comments RSS Feed What about the Marcia Donaldson matter… Has anyone been charged in that case I was hit by a man driving a blue van and he was innocent my life is awful because of the man who hit me… So glad to hear the young man is on the road to recovery although it sounds like it will be a long road They only have 6 months to charge him or he goes free Totally avoidable; if not for our snail-paced kleptocrats too distracted with their cut on the $300mln port eco fiasco to implement their own speed limit changes and order and install new speed limit signs Took them three years and this terrible accident before they were shamed into putting in the cross walk – a week after You are blaming the government because a minibus driver drives dangerously? Do you really believe that drivers always keep to the speed limit posted on a sign If the minibus driver was speeding and driving dangerously then he should have been charged and why haven’t the police proceeded against him if this is the case I have heard of several instances where drivers have not been charged after breaking the law You need to get your facts right before coming here and spread lies The teen was not hit by a mini bus driver I was on the scene of the accident I saw what happened and yes the police have my statement Maybe you should all wait to hear the results of the investigation; not all accidents that occur are the fault of the driver of the vehicle..food for thought The article above says the minibus driver hit him and was arrested at the time for dangerous driving so if people are misinformed there’s a good reason for it they’re not “spreading lies.” Hopefully it’ll all be made clear but there’s no need to attack people just because they believe what they read Seems everyone is misinformed including the victim’s mother who I assume was also there………. I was the kid hit and in the police report it has nothing down as to what any witness saw PLEASE tell me this guy is not still driving a bus He was arrested for dangerous driving in April and still has not been charged "a2fdddb78901f85052e84fba1ee3c2ee" );document.getElementById("f6c5908192").setAttribute( "id"