TY - GEN
AU - Harald Janovjak
AU - Kedrov, Alexej
AU - Cisneros, David
AU - Sapra, Tanuj K
AU - Struckmeier, Jens
AU - Mueller, Daniel J
ID - 3415
T2 - Neurobiology of Aging
TI - Imaging and detecting molecular interactions of single membrane proteins
VL - 27
ER -
TY - GEN
AB - Ising models with pairwise interactions are the least structured, or maximum-entropy, probability distributions that exactly reproduce measured pairwise correlations between spins. Here we use this equivalence to construct Ising models that describe the correlated spiking activity of populations of 40 neurons in the retina, and show that pairwise interactions account for observed higher-order correlations. By first finding a representative ensemble for observed networks we can create synthetic networks of 120 neurons, and find that with increasing size the networks operate closer to a critical point and start exhibiting collective behaviors reminiscent of spin glasses.
AU - Gasper Tkacik
AU - Schneidman, E.
AU - Berry, M. J.
AU - Bialek, William S
ID - 3431
T2 - ArXiv
TI - Ising models for networks of real neurons
ER -
TY - JOUR
AB - The mutational landscape model is a theoretical model describing sequence evolution in natural populations. However, recent experimental work has begun to test its predictions in laboratory populations of microbes. Several of these studies have focused on testing the prediction that the effects of beneficial mutations should be roughly exponentially distributed. The prediction appears to be borne out by most of these studies, at least qualitatively. Another study showed that a modified version of the model was able to predict, with reasonable accuracy, which of a ranked set of beneficial alleles will be fixed next. Although it remains to be seen whether the mutational landscape model adequately describes adaptation in organisms other than microbes, together these studies suggest that adaptive evolution has surprisingly general properties that can be successfully captured by theoretical models.
AU - Betancourt, Andrea J
AU - Jonathan Bollback
ID - 3437
IS - 6
JF - Current Opinion in Genetics & Development
TI - Fitness effects of beneficial mutations: the mutational landscape model in experimental evolution
VL - 16
ER -
TY - CONF
AB - We argue that games are expressive enough to encompass (history-based) access control, (resource) usage control (e.g., dynamic adaptive access control of reputation systems), accountability based controls (e.g., insurance), controls derived from rationality assumptions on participants (e.g., network mechanisms), and their composition. Building on the extensive research into games, we demonstrate that this expressive power coexists with a formal analysis framework comparable to that available for access control.
AU - Krishnendu Chatterjee
AU - Jagadeesan, Rhada
AU - Pitcher, Corin
ID - 3449
TI - Games for controls
ER -
TY - GEN
AB - It is widely accepted that the hippocampus plays a major role in learning and memory. The mossy fiber synapse between granule cells in the dentate gyrus and pyramidal neurons in the CA3 region is a key component of the hippocampal trisynaptic circuit. Recent work, partially based on direct presynaptic patch-clamp recordings from hippocampal mossy fiber boutons, sheds light on the mechanisms of synaptic transmission and plasticity at mossy fiber synapses. A high Na(+) channel density in mossy fiber boutons leads to a large amplitude of the presynaptic action potential. Together with the fast gating of presynaptic Ca(2+) channels, this generates a large and brief presynaptic Ca(2+) influx, which can trigger transmitter release with high efficiency and temporal precision. The large number of release sites, the large size of the releasable pool of vesicles, and the huge extent of presynaptic plasticity confer unique strength to this synapse, suggesting a large impact onto the CA3 pyramidal cell network under specific behavioral conditions. The characteristic properties of the hippocampal mossy fiber synapse may be important for pattern separation and information storage in the dentate gyrus-CA3 cell network.
AU - Bischofberger, Joseph
AU - Engel, Dominique
AU - Frotscher, Michael
AU - Peter Jonas
ID - 3463
IS - 3
T2 - Pflugers Archiv : European Journal of Physiology
TI - Timing and efficacy of transmitter release at mossy fiber synapses in the hippocampal network. (Review)
VL - 453
ER -
TY - CONF
AB - We study infinite stochastic games played by n-players on a finite graph with goals specified by sets of infinite traces. The games are concurrent (each player simultaneously and independently chooses an action at each round), stochastic (the next state is determined by a probability distribution depending on the current state and the chosen actions), infinite (the game continues for an infinite number of rounds), nonzero-sum (the players’ goals are not necessarily conflicting), and undiscounted. We show that if each player has an upward-closed objective, then there exists an ε-Nash equilibrium in memoryless strategies, for every ε>0; and exact Nash equilibria need not exist. Upward-closure of an objective means that if a set Z of infinitely repeating states is winning, then all supersets of Z of infinitely repeating states are also winning. Memoryless strategies are strategies that are independent of history of plays and depend only on the current state. We also study the complexity of finding values (payoff profile) of an ε-Nash equilibrium. We show that the values of an ε-Nash equilibrium in nonzero-sum concurrent games with upward-closed objectives for all players can be computed by computing ε-Nash equilibrium values of nonzero-sum concurrent games with reachability objectives for all players and a polynomial procedure. As a consequence we establish that values of an ε-Nash equilibrium can be computed in TFNP (total functional NP), and hence in EXPTIME.
AU - Krishnendu Chatterjee
ID - 3499
TI - Nash equilibrium for upward-closed objectives
VL - 4207
ER -
TY - CONF
AB - The classical algorithm for solving Bu ̈chi games requires time O(n · m) for game graphs with n states and m edges. For game graphs with constant outdegree, the best known algorithm has running time O(n2/logn). We present two new algorithms for Bu ̈chi games. First, we give an algorithm that performs at most O(m) more work than the classical algorithm, but runs in time O(n) on infinitely many graphs of constant outdegree on which the classical algorithm requires time O(n2). Second, we give an algorithm with running time O(n · m · log δ(n)/ log n), where 1 ≤ δ(n) ≤ n is the outdegree of the game graph. Note that this algorithm performs asymptotically better than the classical algorithm if δ(n) = O(log n).
AU - Krishnendu Chatterjee
AU - Thomas Henzinger
AU - Piterman, Nir
ID - 3500
TI - Algorithms for Büchi Games
ER -
TY - GEN
AB - Embodiments automatically generate an accurate network of watertight NURBS patches from polygonal models of objects while automatically detecting and preserving character lines thereon. These embodiments generate from an initial triangulation of the surface, a hierarchy of progressively coarser triangulations of the surface by performing a sequence of edge contractions using a greedy algorithm that selects edge contractions by their numerical properties. Operations are also performed to connect the triangulations in the hierarchy using homeomorphisms that preserve the topology of the initial triangulation in the coarsest triangulation. A desired quadrangulation of the surface can then be generated by homeomorphically mapping edges of a coarsest triangulation in the hierarchy back to the initial triangulation. This quadrangulation is topologically consistent with the initial triangulation and is defined by a plurality of quadrangular patches. These quadrangular patches are linked together by a (U, V) mesh that is guaranteed to be continuous at patch boundaries. A grid is then preferably fit to each of the quadrangles in the resulting quadrangulation by decomposing each of the quadrangles into k.sup.2 smaller quadrangles. A watertight NURBS model may be generated from the resulting quadrangulation.
AU - Herbert Edelsbrunner
AU - Fu, Ping
AU - Nekhayev, Dmitry V
AU - Facello, Michael
AU - Williams, Steven P
ID - 3510
TI - Method, apparatus and computer program products for automatically generating NURBS models of triangulated surfaces using homeomorphism
ER -
TY - GEN
AB - Methods, apparatus and computer program products provide efficient techniques for designing and printing shells of hearing-aid devices with a high degree of quality assurance and reliability and with a reduced number of manual and time consuming production steps and operations. These techniques also preferably provide hearing-aid shells having internal volumes that can approach a maximum allowable ratio of internal volume relative to external volume. These high internal volumes facilitate the inclusion of hearing-aid electrical components having higher degrees of functionality and/or the use of smaller and less conspicuous hearing-aid shells. A preferred method includes operations to generate a watertight digital model of a hearing-aid shell by thickening a three-dimensional digital model of a shell surface in a manner that eliminates self-intersections and results in a thickened model having an internal volume that is a high percentage of an external volume of the model.
AU - Fu, Ping
AU - Nekhayev, Dmitry V
AU - Herbert Edelsbrunner
ID - 3511
TI - Manufacturing methods and systems for rapid production of hearing-aid shells
ER -
TY - GEN
AB - Methods, apparatus and computer program products provide efficient techniques for reconstructing surfaces from data point sets. These techniques include reconstructing surfaces from sets of scanned data points that have preferably undergone preprocessing operations to improve their quality by, for example, reducing noise and removing outliers. These techniques include reconstructing a dense and locally two-dimensionally distributed 3D point set (e.g., point cloud) by merging stars in two-dimensional weighted Delaunay triangulations within estimated tangent planes. The techniques include determining a plurality of stars from a plurality of points p.sub.i in a 3D point set S that at least partially describes the 3D surface, by projecting the plurality of points p.sub.i onto planes T.sub.i that are each estimated to be tangent about a respective one of the plurality of points p.sub.i. The plurality of stars are then merged into a digital model of the 3D surface.
AU - Fletcher, Yates G
AU - Gloth, Tobias
AU - Herbert Edelsbrunner
AU - Fu, Ping
ID - 3512
TI - Method, apparatus and computer products that reconstruct surfaces from data points
ER -