Equation of state in (2+1)-flavor QCD at physical point with improved Wilson fermion action using gradient flow

We study the energy-momentum tensor and the equation of state as well as the chiral condensate in (2+1)-flavor QCD at the physical point applying the method of Makino and Suzuki based on the gradient flow. We adopt a nonperturbatively O(a)-improved Wilson quark action and the renormalization group-improved Iwasaki gauge action. At Lattice 2016, we have presented our preliminary results of our study in (2+1)-flavor QCD at a heavy u, d quark mass point. We now extend the study to the physical point and perform finite-temperature simulations in the range T \simeq 155--544 MeV (Nt = 4--14 including odd Nt's) at a \simeq 0.09 fm. We show our final results of the heavy QCD study and present some preliminary results obtained at the physical point so far.Comment: 8 pages, 15 figures, talk presented at the 35th International Symposium on Lattice Field Theory (LATTICE 2017), 18-24 June 2017, Granada, Spai

Numerical Analysis on the He II Heat Transport in Channels with a Porous Spacer

Heat transport characteristics in a pressurized He II channel have been studied, using two-dimensional numerical code that is based on the two fluid model. In general, He II heat transport performance gets worse in a either long or narrow channel [1]. If a porous medium is used as a part of the channel to transfer heat to a next channel, it will be expected to improve the heat transport in the channel. In this study, numerical model was based on the channel formed by two FRP plates in parallel and a spacer was inserted in the middle of the channel to divide into two regions. A heater was placed in one of FRP plate to input heat to the channel. Two kinds of spacers were used in the analysis to compare heat transport characteristics; (l) porous spacer, (2) FRP spacer. The temperature distribution and flow velocity vectors of He II in the channel were calculated with a steady state heat input. According to the calculated results, the temperature increase of He II in the heated channel was suppressed in the case of a porous spacer. In addition, the mass flow induced by the thermo-mechanical effect of He II enhanced heat transport capability. The paper also discusses the He II flows within the channel

Utilisation d'une base temporelle a priori issue d'une analyse TFR pour accélérer la prédiction du comportement d'un polymère sous chargement cyclique.

La mise en place d'un critère de fatigue pour les matériaux polymères présentant un comportement visqueux nécessite de simuler un nombre important de cycles afin de prédire le cycle stabilisé. De plus pour prédire correctement ce cycle stabilisé, il est nécessaire de prendre en compte le comportement thermo-viscoélastique de ces matériaux. Ce sujet a déjà été étudié dans le cadre de la méthode des éléments finis par Song Thanh Thao Nguyen et al. en 2013. L'utilisation de la méthode des éléments finis combinée à l'utilisation d'un schéma incrémental en temps a mené à des temps de calculs prohibitifs liés à l'utilisant d'un petit pas de temps et la simulation d'un grand nombre de cycliques. Le choix du pas de temps petit est lié à la présence de temps caractéristiques agissant à des échelles différentes : le temps lié au chargement cyclique, le temps caractéristique de la viscosité et celui de la thermique. De plus, pour certaines valeurs des paramètres, une non convergence des simulations éléments finis a été notée. Afin de pallier ce problème, nous proposons ici de combiner l'utilisation de la Transformée de Fourier Rapide et de la méthode PGD, méthode proposée par Ammar et Chinesta en 2006, pour déterminer a priori une base temporelle réduite. Dans ce papier, l'approche est mise en place dans un cas plus simple que le cas multiphysique visé et se restreint à étudier un problème thermique 3D sous chargement cyclique. Néanmoins, cette étude mène à considérer deux temps caractéristiques : un lié au problème thermique appelé temps physique et un lié au cycle appelé le temps du cycle. La procédure utilisée dans cette étude est la suivante : - La méthode PGD est utilisée pour déterminer la solution du problème 3D. - La solution temporelle obtenue est ensuite traitée avec la Transformée de Fourier Rapide. Les différents modes fréquentiels obtenus sont étudiés pour différents valeurs de paramètres définissant la simulation soit le temps caractéristique, le temps du cycle et l'amplitude du chargement. ? Ces modes sont ensuite utilisés pour déterminer la solution du problème thermique 3D via un algorithme PGD. L'efficacité de cette méthode est étudiée pour différents valeurs des paramètres. Le gain en temps de calcul est ensuite évalué par comparaison à celui obtenu avec la méthode des éléments finis. Selon les conclusions obtenues, cette approche sera étendue à l'étude de la prédiction sous chargement cycliques de matériaux présentant un comportement thermoviscoélastique

Investigation of irradiation effects on highly integrated leading-edge electronic components of diagnostics and control systems for LHD deuterium operation

High-temperature and high-density plasmas are achieved by means of real-time control, fast diagnostic, and high-power heating systems. Those systems are precisely controlled via highly integrated electronic components, but can be seriously affected by radiation damage. Therefore, the effects of irradiation on currently used electronic components should be investigated for the control and measurement of Large Helical Device (LHD) deuterium plasmas. For the precise estimation of the radiation field in the LHD torus hall, the MCNP6 code is used with the cross-section library ENDF B-VI. The geometry is modeled on the computer-aided design. The dose on silicon, which is a major ingredient of electronic components, over nine years of LHD deuterium operation shows that the gamma-ray contribution is dominant. Neutron irradiation tests were performed in the OKTAVIAN at Osaka University and the Fast Neutron Laboratory at Tohoku University. Gamma-ray irradiation tests were performed at the Nagoya University Cobalt-60 irradiation facility. We found that there are ethernet connection failures of programmable logic controller (PLC) modules due to neutron irradiation with a neutron flux of 3  ×  106 cm−2 s−1. This neutron flux is equivalent to that expected at basement level in the LHD torus hall without a neutron shield. Most modules of the PLC are broken around a gamma-ray dose of 100 Gy. This is comparable with the dose in the LHD torus hall over nine years. If we consider the dose only, these components may survive more than nine years. For the safety of the LHD operation, the electronic components in the torus hall have been rearranged

Puberty Predicts Approach But Not Avoidance on the Iowa Gambling Task in a Multinational Sample

According to the dual systems model of adolescent risk taking, sensation seeking and impulse control follow different developmental trajectories across adolescence and are governed by two different brain systems. The authors tested whether different underlying processes also drive age differences in reward approach and cost avoidance. Using a modified Iowa Gambling Task in a multinational, cross‐sectional sample of 3,234 adolescents (ages 9–17; M = 12.87, SD = 2.36), pubertal maturation, but not age, predicted reward approach, mediated through higher sensation seeking. In contrast, age, but not pubertal maturation, predicted increased cost avoidance, mediated through greater impulse control. These findings add to evidence that adolescent behavior is best understood as the product of two interacting, but independently developing, brain systems

Culture of Mouse Embryonic Stem Cells with Serum but without Exogenous Growth Factors Is Sufficient to Generate Functional Hepatocyte-Like Cells

Mouse embryonic stem cells (mESC) have been used to study lineage specification in vitro, including towards a hepatocyte-like fate, and such investigations guided lineage differentiation protocols for human (h)ESC. We recently described a four-step protocol to induce hepatocyte-like cells from hESC which also induced hepatocyte-like cell differentiation of mouse induced pluripotent stem cells. As ESC also spontaneously generate hepatocyte-like cells, we here tested whether the growth factors and serum used in this protocol are required to commit mESC and hESC to hepatocyte-like cells. Culture of mESC from two different mouse strains in the absence of serum and growth factors did not induce primitive streak/definitive endoderm genes but induced default differentiation to neuroectoderm on day 6. Although Activin-A and Wnt3 induced primitive streak/definitive endoderm transcripts most robustly in mESC, simple addition of serum also induced these transcripts. Expression of hepatoblast genes occurred earlier when growth factors were used for mESC differentiation. However, further maturation towards functional hepatocyte-like cells was similar in mESC progeny from cultures with serum, irrespective of the addition of growth factors, and irrespective of the mouse strain. This is in contrast to hESC, where growth factors are required for specification towards functional hepatocyte-like cells. Culture of mESC with serum but without growth factors did not induce preferential differentiation towards primitive endoderm or neuroectoderm. Thus, although induction of primitive streak/definitive endoderm specific genes and proteins is more robust when mESC are exposed to a combination of serum and exogenous growth factors, ultimate generation of hepatocyte-like cells from mESC occurs equally well in the presence or absence of exogenous growth factors. The latter is in contrast to what we observed for hESC. These results suggest that differences exist between lineage specific differentiation potential of mESC and hESC, requiring optimization of different protocols for ESC from either species

Impurity emission characteristics of long pulse discharges in Large Helical Device

Line spectra from intrinsic impurity ions have been monitored during the three kinds of long-pulse discharges (ICH, ECH, NBI). Constant emission from the iron impurity shows no preferential accumulation of iron ion during the long-pulse operations. Stable Doppler ion temperature has been also measured from Fe XX, C V and C III spectra

Age Patterns in Risk Taking Across the World

Epidemiological data indicate that risk behaviors are among the leading causes of adolescent morbidity and mortality worldwide. Consistent with this, laboratory-based studies of age differences in risk behavior allude to a peak in adolescence, suggesting that adolescents demonstrate a heightened propensity, or inherent inclination, to take risks. Unlike epidemiological reports, studies of risk taking propensity have been limited to Western samples, leaving questions about the extent to which heightened risk taking propensity is an inherent or culturally constructed aspect of adolescence. In the present study, age patterns in risk-taking propensity (using two laboratory tasks: the Stoplight and the BART) and real-world risk taking (using self-reports of health and antisocial risk taking) were examined in a sample of 5227 individuals (50.7% female) ages 10–30 (M = 17.05 years, SD = 5.91) from 11 Western and non-Western countries (China, Colombia, Cyprus, India, Italy, Jordan, Kenya, the Philippines, Sweden, Thailand, and the US). Two hypotheses were tested: (1) risk taking follows an inverted-U pattern across age groups, peaking earlier on measures of risk taking propensity than on measures of real-world risk taking, and (2) age patterns in risk taking propensity are more consistent across countries than age patterns in real-world risk taking. Overall, risk taking followed the hypothesized inverted-U pattern across age groups, with health risk taking evincing the latest peak. Age patterns in risk taking propensity were more consistent across countries than age patterns in real-world risk taking. Results suggest that although the association between age and risk taking is sensitive to measurement and culture, around the world, risk taking is generally highest among late adolescents