@article{3809,
abstract = {Neural stem cells in various regions of the vertebrate brain continuously generate neurons throughout life. In the mammalian hippocampus, a region important for spatial and episodic memory, thousands of new granule cells are produced per day, with the exact number depending on environmental conditions and physical exercise. The survival of these neurons is improved by learning and conversely learning may be promoted by neurogenesis. Although it has been suggested that newly generated neurons may have specific properties to facilitate learning, the cellular and synaptic mechanisms of plasticity in these neurons are largely unknown. Here we show that young granule cells in the adult hippocampus differ substantially from mature granule cells in both active and passive membrane properties. In young neurons, T-type Ca2+ channels can generate isolated Ca2+ spikes and boost fast Na+ action potentials, contributing to the induction of synaptic plasticity. Associative long-term potentiation can be induced more easily in young neurons than in mature neurons under identical conditions. Thus, newly generated neurons express unique mechanisms to facilitate synaptic plasticity, which may be important for the formation of new memories.},
author = {Schmidt-Hieber, Christoph and Peter Jonas and Bischofberger, Josef},
journal = {Nature},
number = {6988},
pages = {184 -- 7},
publisher = {Nature Publishing Group},
title = {{Enhanced synaptic plasticity in newly generated granule cells of the adult hippocampus}},
doi = {10.1038/nature02553},
volume = {429},
year = {2004},
}
@article{3810,
abstract = {Voltage-gated potassium (Kv) channels control action potential repolarization, interspike membrane potential, and action potential frequency in excitable cells. It is thought that the combinatorial association between distinct alpha and beta subunits determines whether Kv channels function as non-inactivating delayed rectifiers or as rapidly inactivating A-type channels. We show that membrane lipids can convert A-type channels into delayed rectifiers and vice versa. Phosphoinositides remove N-type inactivation from A-type channels by immobilizing the inactivation domains. Conversely, arachidonic acid and its amide anandamide endow delayed rectifiers with rapid voltage-dependent inactivation. The bidirectional control of Kv channel gating by lipids may provide a mechanism for the dynamic regulation of electrical signaling in the nervous system.},
author = {Oliver, Dominik and Lien, Cheng-Chang and Soom, Malle and Baukrowitz, Thomas and Peter Jonas and Fakler, Bernd},
journal = {Science},
number = {5668},
pages = {265 -- 70},
publisher = {American Association for the Advancement of Science},
title = {{Functional conversion between A-type and delayed rectifier K+ channels by membrane lipids}},
doi = {10.1126/science.1094113},
volume = {304},
year = {2004},
}
@inproceedings{3894,
abstract = {We study infinite stochastic games played by n-players on a finite graph with goals given by sets of infinite traces. The games are stochastic (each player simultaneously and independently chooses an action at each round, and 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 a reachability objective, that is, if the goal for each player i is to visit some subset R-i of the states, then there exists an epsilon-Nash equilibrium in memoryless strategies, for every epsilon > 0. However, exact Nash equilibria need not exist. We study the complexity of finding such Nash equilibria, and show that the payoff of some epsilon-Nash equilibrium in memoryless strategies can be epsilon-approximated in NP. We study the important subclass of n-player turn-based probabilistic games, where at each state at most one player has a nontrivial choice of moves. For turn-based probabilistic games, we show the existence of epsilon-Nash equilibria in pure strategies for games where the objective of player i is a Borel set B-i of infinite traces. However, exact Nash equilibria may not exist. For the special case of omega-regular objectives, we show exact Nash equilibria exist, and can be computed in NP when the omega-regular objectives are expressed as parity objectives.},
author = {Krishnendu Chatterjee and Majumdar, Ritankar S and Jurdziński, Marcin},
pages = {26 -- 40},
publisher = {Springer},
title = {{On Nash equilibria in stochastic games}},
doi = {10.1007/978-3-540-30124-0_6},
volume = {3210},
year = {2004},
}
@inproceedings{3895,
abstract = {In 2-player non-zero-sum games, Nash equilibria capture the options for rational behavior if each player attempts to maximize her payoff. In contrast to classical game theory, we consider lexicographic objectives: first, each player tries to maximize her own payoff, and then, the player tries to minimize the opponent's payoff. Such objectives arise naturally in the verification of systems with multiple components. There, instead of proving that each component satisfies its specification no matter how the other components behave, it often suffices to prove that each component satisfies its specification provided that the other components satisfy their specifications. We say that a Nash equilibrium is secure if it is an equilibrium with respect to the lexicographic objectives of both players. We prove that in graph games with Borel objectives, which include the games that arise in verification, there may be several Nash equilibria, but there is always a unique maximal payoff profile of secure equilibria. We show how this equilibrium can be computed in the case of omega-regular objectives, and we characterize the memory requirements of strategies that achieve the equilibrium.},
author = {Krishnendu Chatterjee and Thomas Henzinger and Jurdziński, Marcin},
pages = {160 -- 169},
publisher = {IEEE},
title = {{Games with secure equilibria}},
doi = {10.1109/LICS.2004.1319610},
year = {2004},
}
@article{205,
author = {Timothy Browning},
journal = {Acta Arithmetica},
number = {3},
pages = {275 -- 295},
publisher = {Instytut Matematyczny},
title = {{Counting rational points on cubic and quartic surfaces}},
doi = {10.4064/aa108-3-7},
volume = {108},
year = {2003},
}