The Baryon-Dark Matter Ratio Via Moduli Decay After Affleck-Dine Baryogenesis

Low-scale supersymmetry breaking in string motivated theories implies the presence of O(100) TeV scale moduli, which generically lead to a significant modification of the history of the universe prior to Big Bang Nucleosynthesis. Such an approach implies a non-thermal origin for dark matter resulting from scalar decay, where the lightest supersymmetric particle can account for the observed dark matter relic density. We study the further effect of the decay on the baryon asymmetry of the universe, and find that this can satisfactorily address the problem of the over-production of the baryon asymmetry by the Affleck-Dine mechanism in the MSSM. Remarkably, there is a natural connection between the baryon and dark matter abundances today, which leads to a solution of the `Cosmic Coincidence Problem'.Comment: 12 pages, no figure. v2: references adde

Understanding Divertor Detachment through CRETIN Modeling - a Work in Progress

From numerous studies aimed at reducing the divertor target plate incident heat flux or understanding divertor detachment, an abundance of evidence supporting the importance of atomic processes in tokamak plasmas now exists. Through use of a multi-dimensional Non-Local Thermodynamic Equilibrium (NLTE) simulation code named CRETIN [1] this repor

A two-armed bandit based scheme for accelerated decentralized learning

The two-armed bandit problem is a classical optimization problem where a decision maker sequentially pulls one of two arms attached to a gambling machine, with each pull resulting in a random reward. The reward distributions are unknown, and thus, one must balance between exploiting existing knowledge about the arms, and obtaining new information. Bandit problems are particularly fascinating because a large class of real world problems, including routing, QoS control, game playing, and resource allocation, can be solved in a decentralized manner when modeled as a system of interacting gambling machines. Although computationally intractable in many cases, Bayesian methods provide a standard for optimal decision making. This paper proposes a novel scheme for decentralized decision making based on the Goore Game in which each decision maker is inherently Bayesian in nature, yet avoids computational intractability by relying simply on updating the hyper parameters of sibling conjugate priors, and on random sampling from these posteriors. We further report theoretical results on the variance of the random rewards experienced by each individual decision maker. Based on these theoretical results, each decision maker is able to accelerate its own learning by taking advantage of the increasingly more reliable feedback that is obtained as exploration gradually turns into exploitation in bandit problem based learning. Extensive experiments demonstrate that the accelerated learning allows us to combine the benefits of conservative learning, which is high accuracy, with the benefits of hurried learning, which is fast convergence. In this manner, our scheme outperforms recently proposed Goore Game solution schemes, where one has to trade off accuracy with speed. We thus believe that our methodology opens avenues for improved performance in a number of applications of bandit based decentralized decision making

Studies of the Heavy Transitional Nuclei using the (p,p') Reactions at 135 MeV

This research was sponsored by the National Science Foundation Grant NSF PHY 87-1440

Light physical activity is positively associated with cognitive performance in older community dwelling adults.

OBJECTIVES: To evaluate the associations between an objective measure of different intensities of physical activity, upper- and lower-limb muscle strength and psychomotor performance and set-shifting domains of cognitive executive function in older adults. DESIGN: A cross-sectional study. METHODS: From the Tasmanian Older Adult Cohort Study, 188 community-dwelling older adults (53.7% female; mean age±SD 63.98±7.3 years) undertook 7-day physical activity behaviour monitoring using an accelerometer. Dynamometers were used to assess leg extension strength. The Trail Maker Tests were used to measure psychomotor processing speed and set-shifting performance. RESULTS: When controlling for age, smoking history, alcohol intake, educational achievement and neuropsychological functioning, higher levels of light physical activity, but not sedentary behaviour or moderate or vigorous physical activity, was found to be associated with better set-shifting performance. Neither physical activity behaviour or muscle strength were found to be associated with psychomotor performance. In addition, older age, greater alcohol intake, and lower levels of educational attainment, verbal learning and memory performance were significantly associated with lower scores on the set-shifting task; whereas older age and reduced neuropsychological functioning were associated with lower psychomotor processing speed scores. CONCLUSIONS: Light physical activity is associated with higher executive functioning in community-dwelling older adults and this strengthens the evidence supporting exercise as a neuroprotective agent. Further studies are needed to understand why light physical activity behaviour positively influences executive functioning, and how such physical activity can be implemented into the daily routine of older adults

Functions of IκB proteins in inflammatory responses to Escherichia coli LPS in mouse lungs

Acute inflammation induced by intrapulmonary LPS requires nuclear factor (NF)-κB RelA. This study elucidates the effects of intrapulmonary LPS on IκB proteins, endogenous inhibitors of RelA, and the effects of deficiency of IκB-β. IκB-α, IκB-β, and IκB-ε each complexed with RelA in uninfected murine lungs. Intratracheal instillation of LPS induced the degradation of IκB-α and IκB-β, as measured by the loss of immunoreactive proteins in non-nuclear fractions. Degradation was apparent by 2 h and sustained through 6 h. In contrast, net IκB-ε content increased over this period. The small amounts of IκB-α and IκB-β that were detected in nuclear fractions from the lungs also decreased over this time frame, whereas intranuclear NF-κB content (including both RelA and p50) increased. The hypophosphorylated form of IκB-β, which facilitates transcription induced by NF-κB, was not detected. Neutrophil recruitment and edema accumulation did not differ between wild type mice and gene-targeted mice deficient in IκB-β, suggesting that IκB-β is not specifically required for these responses. Altogether, these data suggest that RelA is liberated during LPS-induced pulmonary inflammation by the regulated degradation of both IκB-α and IκB-β. In the absence of IκB-β, IκB-α or other inhibitory proteins can regulate NF-κB functions essential to acute neutrophil emigration in the lungs

Cross-cultural effects of color, but not morphological masculinity, on perceived attractiveness of men's faces

This is the post-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2012 ElsevierMuch attractiveness research has focused on face shape. The role of masculinity (which for adults is thought to be a relatively stable shape cue to developmental testosterone levels) in male facial attractiveness has been examined, with mixed results. Recent work on the perception of skin color (a more variable cue to current health status) indicates that increased skin redness, yellowness, and lightness enhance apparent health. It has been suggested that stable cues such as masculinity may be less important to attractiveness judgments than short-term, more variable health cues. We examined associations between male facial attractiveness, masculinity, and skin color in African and Caucasian populations. Masculinity was not found to be associated with attractiveness in either ethnic group. However, skin color was found to be an important predictor of attractiveness judgments, particularly for own-ethnicity faces. Our results suggest that more plastic health cues, such as skin color, are more important than developmental cues such as masculinity. Further, unfamiliarity with natural skin color variation in other ethnic groups may limit observers' ability to utilize these color cues