Effects of photoperiod on body mass, thermogenesis and body composition in Eothenomys miletus during cold exposure

Many small mammals respond to seasonal changes in photoperiod by altering body mass and adiposity. These animals may provide valuable models for understanding the regulation of energy balance. In present study, we examined the effect on body mass, rest metabolic rate, food intake and body composition in cold-acclimated (5 °C) in Eothenomys miletus by transferring them from a short (SD, 8h :16h L: D) to long day photoperiod (LD, 16h: 8h L:D). During the first 4 weeks of exposure to SD, E. miletus decreased body mass. After the next 4 weeks of exposure to LD, which the average difference between body masses of LD and SD voles was 4.76 g. This 14.74% increase in body mass reflected significant increases in absolute amounts of body components, including wet carcass mass, dry carcass mass and body fat mass. After correcting body composition and organ morphology data for the differences in body mass, only livers, kidney, and small intestine were enlarged due to photoperiod treatment during cold exposure. E. miletus increased RMR and energy intake exposure to LD, but maintained a stable level to SD after 28 days. Serum leptin levels were positively correlated with body mass, body fat mass, RMR as well as energy intake. All of the results indicated that E. miletus may provide an attractive novel animal model for investigation of the regulation of body mass and energy balance at organism levels. Leptin is potentially involved in the photoperiod induced body mass regulation and thermogenesis in E. miletus during cold exposure

Power-Law Decay of Standing Waves on the Surface of Topological Insulators

We propose a general theory on the standing waves (quasiparticle interference pattern) caused by the scattering of surface states off step edges in topological insulators, in which the extremal points on the constant energy contour of surface band play the dominant role. Experimentally we image the interference patterns on both Bi$_2$Te$_3$ and Bi$_2$Se$_3$ films by measuring the local density of states using a scanning tunneling microscope. The observed decay indices of the standing waves agree excellently with the theoretical prediction: In Bi$_2$Se$_3$, only a single decay index of -3/2 exists; while in Bi$_2$Te$_3$ with strongly warped surface band, it varies from -3/2 to -1/2 and finally to -1 as the energy increases. The -1/2 decay indicates that the suppression of backscattering due to time-reversal symmetry does not necessarily lead to a spatial decay rate faster than that in the conventional two-dimensional electron system. Our formalism can also explain the characteristic scattering wave vectors of the standing wave caused by non-magnetic impurities on Bi$_2$Te$_3$.Comment: 4 pages, 3 figure

Longitudinal associations between triglycerides and metabolic syndrome components in a Beijing adult population, 2007-2012

Background: Longitudinal associations between triglycerides (TG) and other metabolic syndrome (MetS) components have rarely been reported. The purpose was to investigate the longitudinal association between TG and other MetS components with time. Methods: The longitudinal study was established in 2007 on individuals who attended health check-ups at Beijing Tongren Hospital and Beijing Xiaotangshan Hospital. Data used in this study was based on 7489 participants who had at least three health check-ups over a period of 5-year follow up. Joint model was used to explore longitudinal associations between TG and other MetS components after adjusted for age. Results: There were positive correlations between TG and other MetS components except for high density lipoprotein (HDL), and the correlations increased with time. A negative correlation was displayed between TG and HDL, and the correlation also increased with time. Among all five pairs of TG and other MetS components, the marginal correlation between TG and body mass index (BMI) was the largest for both men and women. The marginal correlation between TG and fasting plasma glucose was the smallest for men, while the marginal correlation between TG and diastolic blood pressure was the smallest for women. Conclusions: The longitudinal association between TG and other MetS components increased with time. Among five pairs of TG and other MetS components, the longitudinal correlation between TG and BMI was the largest. It is important to closely monitor subjects with high levels of TG and BMI in health check-up population especially for women, because these two components are closely associated with development of hypertension, diabetes, cardiovascular disease and other metabolic diseases

PSO based TMD & ATMD control for high-rise structure excited by simulated fluctuating wind field

This paper reports a novel control strategy combined with artificial intelligence for wind-induced vibration control of a high-rise structure and also provides a broader idea for traditional structural vibration control. The fast Fourier transform based on decimation-in-time was used to optimize the waves with a weighted amplitude method, and the wind speed field was numerically generated according to a Davenport - type fluctuating wind speed spectrum. A second-generation benchmark structure was selected as the high-rise building model. Tuned mass damper (TMD) and active tuned mass damper (ATMD) served as the controller, and the linear- quadratic- Gaussian algorithm served as the active control algorithm for ATMD. Simultaneously, the particle swarm  optimization algorithm was introduced, and the integral of the absolute value of the error based on the relative displacement of floors with regard to the ground level was defined as a performance index for optimizing. The numerical results reveal that both of the two proposed controllers have excellent capability in reducing wind-induced vibrations in high-rise buildings; moreover, the PSO-based ATMD performed better than PSO-based TMD