Discrete mechanics Based on Finite Element Methods

Discrete Mechanics based on finite element methods is presented in this paper. We also explore the relationship between this discrete mechanics and Veselov discrete mechanics. High order discretizations are constructed in terms of high order interpolations.Comment: 14 pages, 0 figure

Association between work stress and health behaviours in Korean and Japanese ageing studies: a cross-sectional study

OBJECTIVES: Limited research has focused on the association between work stress and health behaviours in Asian countries. We aimed to explore the effect of work stress on two health behaviours among employees aged 45 years or above in two countries with ageing populations, Korea and Japan. DESIGN: A cross-sectional study. SETTING: This secondary data analysis was conducted on baseline data from the Korean Longitudinal Study of Aging (KLoSA, 2006) and the Japanese Study of Aging and Retirement (JSTAR, 2007 and 2009). PARTICIPANTS: Included in the analytical sample were 4982 responders without missing data aged 45 years or older who reported work positions and hours (KLoSA n=3478, JSTAR n=1504). MAIN OUTCOME MEASURES: Work stress was represented by the short version of the effort-reward imbalance (ERI) model. We used logistic regression and multinomial logistic regression to investigate the association between work stress and smoking (binary current smoking) and between work stress and drinking (categorical volume of alcohol). Socioeconomic and work-related characteristics were taken into consideration, and we examined the potential interaction between ERI and gender. RESULTS: Work stress as measured by ERI ratio was significantly associated with both smoking and drinking in the KLoSA analysis; after the model was fully adjusted, ORs were 1.45 (95% CI 1.17 to 1.80) and 1.44 (95% CI 1.09 to 1.90), respectively. In analysis of the data from JSTAR, the ERI ratio was associated with smoking (OR 1.37, 95% CI 1.01 to 1.89) but not with drinking. No statistically significant interaction was found between ERI and gender in any model (p=0.82 in KLoSA data and p=0.19 in JSTAR data). CONCLUSIONS: Statistically significant associations were found between work stress and both smoking and drinking behaviours in Korea and between work stress and smoking in Japan. Government integration of effort-reward balance programmes and health promotion programmes could effectively promote population health in these two Asian countries

Quantum Renormalization of the Spin Hall Effect

By quantum Monte Carlo simulation of a realistic multiorbital Anderson impurity model, we study the spin-orbit interaction (SOI) of an Fe impurity in Au host metal. We show, for the first time, that the SOI is strongly renormalized by the quantum spin fluctuation. Based on this mechanism, we can explain why the gigantic spin Hall effect in Au with Fe impurities was observed in recent experiment, while it is not visible in the anomalous Hall effect. In addition, we show that the SOI is strongly renormalized by the Coulomb correlation U. Based on this picture, we can explain past discrepancies in the calculated orbital angular momenta for an Fe impurity in an Au host.Comment: 4 pages, 3 figure

Constraints on ultra-slow-roll inflation with the NANOGrav 15-Year Dataset

Ultra-slow-roll~(USR) inflation predicts an exponential amplification of scalar perturbations at small scales, which leads to a stochastic gravitational wave background~(SGWB) through the coupling of the scalar and tensor modes at the second-order expansion of the Einstein equation. In this work, we search for such a scalar-induced SGWB from the NANOGrav 15-year (NG15) dataset, and find that the SGWB from USR inflation could explain the observed data. We place constraints on the amplitude of the scalar power spectrum to $P_{\mathrm{Rp}} > 10^{-1.80}$ at $95\%$ confidence level (C.L.) at the scale of $k\sim 20\, \mathrm{pc}^{-1}$. We find that $\log_{10} P_{\mathrm{Rp}}$ degenerates with the peak scale $\log_{10} k_{\mathrm{p}}$. We also obtain the parameter space allowed by the data in the USR inflationary scenario, where the $e$-folding numbers of the duration of the USR phase has a lower limit $\Delta N > 2.80$ ($95\%$ C.L.) when the USR phase ends at $N\approx 20$. Since the priors for the model parameters %in the USR model are uncertain, we do not calculate the Bayes factors. Instead, to quantify the goodness of fit, we calculate the maximum values of the log-likelihood for USR inflation, bubble collision of the cosmological phase transition, and inspiraling supermassive black hole binaries (SMBHBs), respectively. Our results imply that the SGWB from USR inflation can fit the data better than the one from SMBHBs.Comment: 6 pages, 4 figure