We study a repeated game with asymmetric information about a dynamic state of nature. In the course of the game, the better informed player can communicate some or all of his information with the other. Our model covers costly and/or bounded communication. We characterize the set of equilibrium payoffs, and contrast these with the communication equilibrium payffs, which by definition entail no communication costs.
Electron dynamics in metallic clusters are examined using a time-dependent density functional theory that includes a “memory term,” i.e., attempts to describe temporal nonlocal correlations. Using the Iwamoto, Gross, and Kohn exchange-correlation XC kernel, we construct a translationally invariant memory action from which an XC potential is derived that is translationally covariant and exerts zero net force on the electrons. An efficient and stable numerical method to solve the resulting Kohn-Sham equations is presented. Using this framework, we study memory effects on electron dynamics in spherical jellium gold clusters. We find memory significantly broadens the surface plasmon absorption line, yet considerably less than measured in real gold clusters, attributed to the inadequacy of the jellium model. Memory effects on nonlinear spectroscopy are studied as well: a real-time pump-probe setup is used to study the temporal decay profile of the plasmon, finding a fast decay followed by slower tail; and in high harmonic generation, we show that memory narrows and redshifts emission lines.
Raz Yosef, Beyond Flesh: Queer Masculinities and Nationalism in Israeli Cinema (Rutgers University Press, 2004), pp. 203, $62 (cloth), $21.95 (paper). Danny Kaplan, Brothers and Others in Arms: The Making [...]
The cellular cytoskeleton is a complex dynamical network that constantly remodels as cells divide and move. This reorganization process occurs not only at the cell membrane, but also in the cell interior (bulk). During locomotion, regulated actin assembly near the plasma membrane produces lamellipodia and filopodia. Therefore, most in vitro experiments explore phenomena taking place in the vicinity of a surface. To understand how the molecular machinery of a cell self-organizes in a more general way, we studied bulk polymerization of actin in the presence of actin-related protein 2/3 complex and a nucleation promoting factor as a model for actin assembly in the cell interior separate from membranes. Bulk polymerization of actin in the presence of the verprolin homology, cofilin homology, and acidic region, domain of Wiskott-Aldrich syndrome protein, and actin-related protein 2/3 complex results in spontaneous formation of diffuse aster-like structures. In the presence of fascin these asters transition into stars with bundles of actin filaments growing from the surface, similar to star-like structures recently observed in vivo. The transition from asters to stars depends on the ratio [fascin]/[G actin]. The polarity of the actin filaments during the transition is preserved, as in the transition from lamellipodia to filopodia. Capping protein inhibits star formation. Based on these experiments and kinetic Monte Carlo simulations, we propose a model for the spontaneous self-assembly of asters and their transition into stars. This mechanism may apply to the transition from lamellipodia to filopodia in vivo.
Mycoplasma fermentans is an extracellular microorganism capable of adhering to the surface of host cells. It has been recently shown that plasminogen binding to M. fermentans in the presence of the urokinase-type plasminogen activator promotes the invasion of host cells by this organism. In this report, we show that viable mycoplasmas persist within the infected HeLa cells for prolonged periods of time despite the expectation that within host cells the organism may be exposed to oxidative stress. Using cyclic voltammetry and luminol-enhanced chemiluminescence assays, we detected a potent reducing antioxidant activity in M. fermentans. The reducing antioxidant activity was heat stable, not affected by proteolysis and was almost totally lost upon dialysis suggesting that the activity is due to a nonproteinaceus low molecular weight antioxidant. This antioxidant was partially purified by Bio-Gel column chromatography followed by high-pressure liquid chromatographic analysis. We suggest that the high reducing antioxidant capacity in M. fermentans is a principal defense mechanism playing a major role in the battle of the organism against oxidative stress within the host cells.
O. Kella. 2006. “Reflecting thoughts.” Statistics and Probability Letters, 76, Pp. 1808-1811.
The job chains model of local labor market change is a demand-driven analytic device for estimating the effects of new job creation. This paper explores the effects of restricting supply, i.e., limiting job access, on the model’s primary outcomes: vacancy chain multipliers, welfare effects, and distributional impacts. Major sources of labor supply are the local unemployed, out of the labor force and in-migrants. Three simulations are reported relating to (1) restricting new jobs to current local residents (i.e., no in-migrants), (2) restricting new jobs to current residents in the first round of hiring only, and (3) restricting hiring to local unemployed/out of labor force on the first round alone. The results are compared to the basic model that assumes no supply-side restrictions. In terms of chain length, welfare effects, distributional impacts, and policy palatability, first-round restrictions on in-migrants would seem to be the most plausible option. However, as an economic development strategy, well-targeted demand-side initiatives would still seem to be preferable.
The second edition of Bentley Layton’s A Coptic Grammar with Chrestomathy and Glossary: Sahidic Dialect, so quickly replacing the first of 2000, can only be viewed with gratification, answering as it does the evident demand that it must imply. The main improvement and real expansion of the present edition is in its Index of Citations. (“Revised and Expanded With an Index of Citations”: the question of what constitutes “revision” — see Glenn E. Snyder’s review in RBL 3 (2005) — and the valency-grammar snag of whether “expanded with” can be seen as an alternative construction to “expanded by”, need hardly be addressed here. However, a list, technically easy to compile, of additions, omissions and replacements could have prevented misunderstanding and forestalled protest.) The Index of Citations is especially useful for Shenoute؛ in fact, it can serve as the basis of a “Shenoutean sub-grammar” (e.g. in isolating exclusively or predominantly Shenoutean usage — consider the Conjunctive, p. 283, or adnominal xe- in negative environment, §483). But it also brings home rather sharply a striking imbalance in documentation, as well as the programmatic limitations of the Grammar’s corpus database, already commented on in reviews of the first edition. One regrets that the author has not exploited the rare opportunity of a new edition coming out so soon after the first, to provide at the least some highlights for the grammatical usage of more Sahidic texts, from the Pistis Sophia to non-literary sources (including documents and such specialized textemes as medical prescriptions) and such “Late Sahidic” genres as martyrologies and other patristic sources, and cases like Drescher’s Legends, which are grammatically distinctive and probably illuminating for their glimpses into Coptic colloquial usage.
We measured seasonal variation in the locomotor behavior of newly emerged adult honey bee workers in the laboratory. Analyses of bees from 12 colonies, 7 of which were tested once and 5 tested more than once, revealed seasonal changes in the free-running period (FRP) of the rhythm for locomotor behavior, with an increase from spring to summer. At the same time there was a decrease in the age at onset of circadian rhythmicity. There were no seasonal changes in overall levels of locomotor activity. Temperature and photoperiod, the only factors known to mediate plasticity in the insect clock, cannot account for the observed seasonal variation because bees were maintained under constant conditions. In a second experiment we found no differences in the FRP of nurses and foragers obtained from colonies maintained in a 12 h light: 12 h dark illumination regime. These findings suggest that exposure to unknown cues during preadult stages may affect the circadian behavior of adult bees.
Photodissociation of I-2 in the I2Ar17 cluster is studied by quantum wavepacket simulations, using time-dependent mean-field potentials. It is found that: (a) Initial energy transfer from the 12 is Mostly to three cluster modes, which undergo multiquantum excitation. Several other modes undergo single-quantum excitation. (b) Coherent phase transfer from the 12 to specific cluster modes is found. (c) Energy transfer from initially-excited modes to the other modes becomes large after 0.6 ps. Phase space interpretation is provided by computed Wigner distributions in time. (c) 2006 Elsevier B.V. All rights reserved.