Heterologous Expression of Camellia sinensis Late Embryogenesis Abundant Protein Gene 1(CsLEA1)Confers Cold Stress Tolerance in Escherichia coli and Yeast

Late embryogenesis abundant(LEA)proteins play an important role in plant growth and development,as well as in the plant response to various abiotic stresses.In this study,CsLEA1,a novel gene encoding a LEA_3 subfamily protein,was successfully cloned froma tea plant[Camellia sinensis(L.)O.Kuntze].Bioinformatics analysis and prokaryotic expression assays showed that CsLEA1 is a typical hydrophilic protein with a molecular weight of approximately 10.4 kD.Expression analyses revealed that the transcription of CsLEA1 in C.sinensis leaves was significantly induced by cold stress.In addition,the heterologous expression of CsLEA1 increased the tolerance of Escherichia coli and yeast to cold stress,which might be closely related to the low molecular weight and high hydrophilicity of the CsLEA1.Taken together,our results suggest that CsLEA1 might have an important function in the tolerance of C.sinensis to cold stress,thus providing a potential application in molecular breeding to enhance the cold stress tolerance of tea plants.

Forecasting Realized Volatility Using Subsample Averaging

When the observed price process is the true underlying price process plus microstructure noise, it is known that realized volatility (RV) estimates will be overwhelmed by the noise when the sampling frequency approaches infinity. Therefore, it may be optimal to sample less frequently, and averaging the less frequently sampled subsamples can improve estimation for quadratic variation. In this paper, we extend this idea to forecasting daily realized volatility. While subsample averaging has been proposed and used in estimating RV, this paper is the first that uses subsample averaging for forecasting RV. The subsample averaging method we examine incorporates the high frequency data in different levels of systematic sampling. It first pools the high frequency data into several subsamples, then generates forecasts from each subsample, and then combines these forecasts. We find that in daily S&P 500 return realized volatility forecasts, subsample averaging generates better forecasts than those using only one subsample.

Bending fracture behavior of freestanding (Gd0.9Yb0.1)2Zr2O7 coatings by using digital image correlation and FEM simulation with 3D geometrical reconstruction

It is important to investigate the mechanical performances of (Gd0.9Yb0.1)2Zr2O7 (GYbZ) materials deposited on irregular substrates for improving new thermal barrier coatings. Three-point bending fracture characteristics of freestanding GYbZ coating prepared by supersonic plasma sprayed(SPS) technique were investigated with the help of digital image correlation technique. The cracking time, crack propagation path, and mechanical properties of GYbZ coating were obtained. Meanwhile, the X-ray computed tomography technique was introduced to scan the microstructure of freestanding GYbZ coatings, which are used to establish three-dimensional(3D) finite element model by using the Avizo software. The brittle cracking criterion was applied to describe the bending fracture process of GYbZ coatings. The critical cracking strain was estimated as 0.36%±0.03% by repeatedly comparing the difference between the experimental and simulated curves. The results would be extended to predict the dangerous region and failure mechanisms of GYbZ coatings deposited on irregular substrate during finite element simulations.

监狱基层民警依法履职保护机制探析

在基层监狱的实际执法过程中,监狱的执法地位和执法权威囿于诸多因素存在影响执法效果的方面,会导致民警依法履职的主观愿望与客观效果相悖的局面。新时期监狱工作新要求对于监狱基层民警的依法履职提出了更高标准,应从人文关怀、容错纠错、执勤模式、智慧平台等四个方面着手,建立有效的保护机制,缓解监狱基层民警依法履行职责的风险问题。