Gap Symmetry and Thermal Conductivity in Nodal Superconductors

Here we consider the universal heat conduction and the angular dependent thermal conductivity in the vortex state for a few nodal superconductors. We present the thermal conductivity as a function of impurity concentration and the angular dependent thermal conductivity in a few nodal superconductors. This provides further insight in the gap symmetry of superconductivity in Sr$_2$RuO$_4$ and UPd$_2$Al$_3$.Comment: 2 pages, proceedings of SCES '0

Monte Carlo Bayesian Reinforcement Learning

Bayesian reinforcement learning (BRL) encodes prior knowledge of the world in a model and represents uncertainty in model parameters by maintaining a probability distribution over them. This paper presents Monte Carlo BRL (MC-BRL), a simple and general approach to BRL. MC-BRL samples a priori a finite set of hypotheses for the model parameter values and forms a discrete partially observable Markov decision process (POMDP) whose state space is a cross product of the state space for the reinforcement learning task and the sampled model parameter space. The POMDP does not require conjugate distributions for belief representation, as earlier works do, and can be solved relatively easily with point-based approximation algorithms. MC-BRL naturally handles both fully and partially observable worlds. Theoretical and experimental results show that the discrete POMDP approximates the underlying BRL task well with guaranteed performance.Comment: Appears in Proceedings of the 29th International Conference on Machine Learning (ICML 2012

The factors affecting pregnancy outcomes in the second trimester pregnant women

Adequate nutrient intake during pregnancy is important to fetal and maternal health. The purpose of this study was to investigate the factors affecting birth weight and gestational age and to provide basic data to promote more favorable pregnancy outcomes. Data were collected from 234 pregnant women at two hospitals in Seoul. Demographic characteristics, anthropometric measurements and health related habits were obtained using a questionnaire at the hospital visit during the second trimester. Dietary intakes were estimated by 24 hour recall at the hospital visit during the second trimester. Data on pregnancy outcomes, including birth weights and gestational ages, were obtained from hospital records after delivery. Birth weights were divided into a low birth weight group (birth weight<3.1 kg), a normal birth weight group (3.1-3.6 kg) and a high birth weight group (>3.6 kg). Gestational ages were divided into tertiles according to the gestational age of the subjects: group 1 (<38.53 weeks), group 2 (38.53-40.00 weeks) and group 3 (>40.00 weeks). The number of family members was significantly lower in the low birth weight group than in the normal birth weight group (p<0.05). In the low birth weight group, pregnancy weight was significantly lower than in the high birth weight group (p<0.05). Health related habits were not significantly different among any of the groups. Intakes of fiber, phosphorous, iron, vitamin B6 and folic acid were significantly higher in the high birth weight group than the low birth weight group (p<0.05). Gestational age was not significantly affected by nutrient intakes, but birth weight was affected by nutrient intake in the results of this study. Therefore, the adequacy of nutrient intake is important for the improvement of pregnancy outcomes

Preparative Synthesis of dTDP-L-Rhamnose Through Combined Enzymatic Pathways

dTDP-L-rhamnose, an important precursor of O-antigen, was prepared on a large scale from dTMP by executing an one-pot reaction in which six enzymes are involved. Two enzymes, dTDP-4-keto-6-deoxy-D-glucose 3,5-epimerase and dTDP-4-keto-rhamnose reductase, responsible for the conversion of dTDP-4-keto-6-deoxy- D-glucose to dTDP-L-rhamnose, were isolated from their putative sequences in the genome of Mesorhizobium loti, functionally expressed in Escherichia coli, and their enzymatic activities were identified. The two enzymes were combined with an enzymatic process for dTDP-4- keto-6-deoxy-D-glucose involving TMP kinase, acetate kinase, dTDP-glucose synthase, and dTDP-glucose 4,6- dehydratase, which allowed us to achieve a preparative scale synthesis of dTDP-L-rhamnose using dTMP and glucose-1-phosphate as starting materials. About 82% yield of dTDP-L-rhamnose was obtained based on initial dTMP concentration at 20 mM dTMP, 1 mM ATP, 10 mM NADH, 60 mM acetyl phosphate, and 80 mM glucose-1- phosphate. From the reaction with 20 ml volume, approximately 180 mg of dTDP-L-rhamnose was obtained in an overall yield of 60% after two-step purification, that is, anion exchange chromatography and gel filtration for desalting. The purified product was identifiedbyHPLC, ESI-MS,andNMR,showingabout95%purity

The Strain of Spanning Structural Holes: How Brokering Leads to Burnout and Abusive Behavior

Connecting otherwise disconnected individuals and groups—spanning structural holes—can earn social network brokers faster promotions, higher remuneration, and enhanced creativity. Organizations also benefit through improved communication and coordination from these connections between knowledge silos. Neglected in prior research, however, has been theory and evidence concerning the psychological costs to individuals of engaging in brokering activities. We build new theory concerning the extent to which keeping people separated (i.e., tertius separans brokering) relative to bringing people together (i.e., tertius iungens brokering) results in burnout and in abusive behavior toward coworkers. Engagement in tertius separans brokering, relative to tertius iungens brokering, we suggest, burdens people with onerous demands while limiting access to resources necessary to recover. Across three studies, we find that tertius separans leads to abusive behavior of others, mediated by an increased experience of burnout on the part of the broker. First, we conducted a five-month field study of burnout and abusive behavior, with brokering assessed via email exchanges among 1,536 university employees in South America. Second, we examined time-separated data on self-reported brokering behaviors, burnout, and coworker abuse among 242 employees of U.S. organizations. Third, we experimentally investigated the effects of the two types of brokering behaviors on burnout and abusive behavior for 273 employed adults. The results across three studies showed that tertius separans brokering puts the broker at an increased risk of burnout and subsequent abusive behavior toward others in the workplace