Non-equilibrium and non-linear stationary state in thermoelectric materials

Efficiency of thermoelectric materials is characterized by the figure of merit Z. Z has been believed to be a peculiar material constant. However, the accurate measurements in the present work reveal that Z has large size dependence and a non-linear temperature distribution appears as stationary state in the thermoelectric material. The observation of these phenomena is achieved by the Harman method. This method is the most appropriate way to investigate the thermoelectric properties because the dc and ac resistances are measured by the same electrode configuration. We describe the anomalous thermoelectric properties observed in mainly (Bi,Sb)2Te3 by the Harman method and then insist that Z is not the peculiar material constant but must be defined as the physical quantity dependent of the size and the position in the material.Comment: 9 pages, 4 figures. submitted to Applied Physics Lette

Payoff levels, loss avoidance, and equilibrium selection in the Stag Hunt: an experimental study

Game theorists typically assume that changing a game’s payoff levels—by adding the same constant to, or subtracting it from, all payoffs—should not affect behavior. While this invariance is an implication of the theory when payoffs mirror expected utilities, it is an empirical question when the “payoffs” are actually money amounts. In particular, if individuals treat monetary gains and losses differently, then payoff–level changes may matter when they result in positive payoffs becoming negative, or vice versa. We report the results of a human–subjects experiment designed to test for two types of loss avoidance: certain–loss avoidance (avoiding a strategy leading to a sure loss, in favor of an alternative that might lead to a gain) and possible–loss avoidance (avoiding a strategy leading to a possible loss, in favor of an alternative that leads to a sure gain). Subjects in the experiment play three versions of Stag Hunt, which are identical up to the level of payoffs, under a variety of treatments. We find differences in behavior across the three versions of Stag Hunt; these differences are hard to detect in the first round of play, but grow over time. When significant, the differences we find are in the direction predicted by certain– and possible–loss avoidance. Our results carry implications for games with multiple equilibria, and for theories that attempt to select among equilibria in such games

Rad62 protein functionally and physically associates with the Smc5/Smc6 protein complex and is required for chromosome integrity and recombination repair in fission yeast

Smc5 and Smc6 proteins form a heterodimeric SMC (structural maintenance of chromosome) protein complex like SMC1-SMC3 cohesin and SMC2-SMC4 condensin, and they associate with non-SMC proteins Nse1 and Nse2 stably and Rad60 transiently. This multiprotein complex plays an essential role in maintaining chromosome integrity and repairing DNA double strand breaks (DSBs). This study characterizes a Schizosaccharomyces pombe mutant rad62-1, which is hypersensitive to methyl methanesulfonate (MMS) and synthetically lethal with rad2 (a feature of recombination mutants). rad62-1 is hypersensitive to UV and gamma rays, epistatic with rhp51, and defective in repair of DSBs. rad62 is essential for viability and genetically interacts with rad60, smc6, and brc1. Rad62 protein physically associates with the Smc5-6 complex. rad62-1 is synthetically lethal with mutations in the genes promoting recovery from stalled replication, such as rqh1, srs2, and mus81, and those involved in nucleotide excision repair like rad13 and rad16. These results suggest that Rad62, like Rad60, in conjunction with the Smc5-6 complex, plays an essential role in maintaining chromosome integrity and recovery from stalled replication by recombination

RAD6-RAD18-RAD5-pathway-dependent tolerance to chronic low-dose ultraviolet light

In nature, organisms are exposed to chronic low- dose ultraviolet light ( CLUV) as opposed to the acute high doses common to laboratory experiments. Analysis of the cellular response to acute high-dose exposure has delineated the importance of direct DNA repair by the nucleotide excision repair pathway(1) and for checkpoint-induced cell cycle arrest in promoting cell survival(2). Here we examine the response of yeast cells to CLUV and identify a key role for the RAD6-RAD18-RAD5 error- free postreplication repair (RAD6 error-free PRR) pathway(3,4) in promoting cell growth and survival. We show that loss of the RAD6 error- free PRR pathway results in DNA-damage-checkpoint- induced G2 arrest in CLUV-exposed cells, whereas wild-type and nucleotide-excision-repair-deficient cells are largely unaffected. Cell cycle arrest in the absence of the RAD6 error- free PRR pathway was not caused by a repair defect or by the accumulation of ultraviolet-induced photoproducts. Notably, we observed increased replication protein A (RPA) and Rad52 - yellow fluorescent protein foci(5) in the CLUV- exposed rad18 Delta cells and demonstrated that Rad52- mediated homologous recombination is required for the viability of the rad18 Delta cells after release from CLUV- induced G2 arrest. These and other data presented suggest that, in response to environmental levels of ultraviolet exposure, the RAD6 error- free PRR pathway promotes replication of damaged templates without the generation of extensive single- stranded DNA regions. Thus, the error- free PRR pathway is specifically important during chronic low- dose ultraviolet exposure to prevent counter- productive DNA checkpoint activation and allow cells to proliferate normally

Phase structure of lattice QCD for general number of flavors

We investigate the phase structure of lattice QCD for the general number of flavors in the parameter space of gauge coupling constant and quark mass, employing the one-plaquette gauge action and the standard Wilson quark action. Performing a series of simulations for the number of flavors $N_F=6$--360 with degenerate-mass quarks, we find that when $N_F \ge 7$ there is a line of a bulk first order phase transition between the confined phase and a deconfined phase at a finite current quark mass in the strong coupling region and the intermediate coupling region. The massless quark line exists only in the deconfined phase. Based on these numerical results in the strong coupling limit and in the intermediate coupling region, we propose the following phase structure, depending on the number of flavors whose masses are less than $\Lambda_d$ which is the physical scale characterizing the phase transition in the weak coupling region: When $N_F \ge 17$, there is only a trivial IR fixed point and therefore the theory in the continuum limit is free. On the other hand, when $16 \ge N_F \ge 7$, there is a non-trivial IR fixed point and therefore the theory is non-trivial with anomalous dimensions, however, without quark confinement. Theories which satisfy both quark confinement and spontaneous chiral symmetry breaking in the continuum limit exist only for $N_F \le 6$.Comment: RevTeX, 20 pages, 43 PS figure

Antiproton Production in p+d Reaction at Subthreshold Energies

An enhancement of antiprotons produced in p+d reaction in comparison with ones in p+p elementary reaction is investigated. In the neighborhood of subthreshold energy the enhancement is caused by the difference of available energies for antiproton production. The cross section in p+d reaction, on the other hand, becomes just twice of the one in elementary p+p reaction at the incident energy far from the threshold energy when non-nucleonic components in deuteron target are not considered.Comment: LaTeX,7 pages with 5 eps figure