Identification of distant co-evolving residues in antigen 85C from Mycobacterium tuberculosis using statistical coupling analysis of the esterase family proteins

A fundamental goal in cellular signaling is to understand allosteric communication, the process by which sig-nals originating at one site in a protein propagate reliably to affect distant functional sites. The general principles of protein structure that underlie this process remain unknown. Statistical coupling analysis （SCA） is a statistical technique that uses evolutionary data of a protein family to measure correlation between distant functional sites and suggests allosteric communication. In proteins, very distant and small interactions between collections of amino acids provide the communication which can be important for signaling process. In this paper, we present the SCA of protein alignment of the esterase family （pfam ID： PF00756） containing the sequence of antigen 85C secreted by Mycobacterium tuberculosis to identify a subset of interacting residues. Clustering analysis of the pairwise correlation highlighted seven important residue positions in the esterase family alignments. These resi-dues were then mapped on the crystal structure of antigen 85C （PDB ID： 1DQZ）. The mapping revealed corre-lation between 3 distant residues （Asp38, Leu123 and Met125） and suggests allosteric communication between them. This information can be used for a new drug against this fatal disease.

Dynamic thermo-mechanical coupled simulation of statistically inhomogeneous materials by statistical second-order two-scale method

In this paper,a statistical second-order twoscale（SSOTS） method is developed to simulate the dynamic thcrmo-mechanical performances of the statistically inhomogeneous materials.For this kind of composite material,the random distribution characteristics of particles,including the shape,size,orientation,spatial location,and volume fractions,are all considered.Firstly,the repre.sentation for the microscopic configuration of the statistically inhomogeneous materials is described.Secondly,the SSOTS formulation for the dynamic thermo-mechanical coupled problem is proposed in a constructive way,including the cell problems,effective thermal and mechanical parameters,homogenized problems,and the SSOTS formulas of the temperatures,displacements,heat flux densities and stresses.And then the algorithm procedure corresponding to the SSOTS method is brought forward.The numerical results obtained by using the SSOTS algorithm are compared with those by classical methods.In addition,the thermo-mechanical coupling effect is studied by comparing the results of coupled case with those of uncoupled case.It demonstrates that the coupling effect on the temperatures,heat flux densities,displacements,and stresses is very distinct.The results show that the SSOTS method is valid to predict the dynamic thermo-mechanical coupled performances of statistically inhomogeneous materials.

Dynamic thermo-mechanical coupled response of random particulate composites:A statistical two-scale method

This paper focuses on the dynamic thermo-mechanical coupled response of random particulate composite materials. Both the inertia term and coupling term are considered in the dynamic coupled problem. The formulation of the problem by a statistical second-order two-scale （SSOTS） analysis method and the algorithm procedure based on the finite-element difference method are presented. Numerical results of coupled cases are compared with those of uncoupled cases. It shows that the coupling effects on temperature, thermal flux, displacement, and stresses are very distinct, and the micro- characteristics of particles affect the coupling effect of the random composites. Furthermore, the coupling effect causes a lag in the variations of temperature, thermal flux, displacement, and stresses.

New Resolution to Coupling Loss Factor of Beam Plate Structure

The transmission of transverse vibrational energy of a vertically rigid beam plate coupled structure is analyzed to get the theoretical results of coupling loss factor(CLF), a very important parameter in statistical energy analysis(SEA). The modal analysis method is used to discuss the vibration energy of the typical model, as well as the power flow between the two subsystems. Furthermore, the resolution to the coupling loss factor is also derived and compared with the measured values. The analytical results of the coupling loss factor agree with the measured ones fully, this new resolution is significant for the application of SEA.

A New Statistical Downscaling Scheme for Predicting Winter Precipitation in China

An effective statistical downscaling scheme was developed on the basis of singular value decomposition to predict boreal winter(December-January-February)precipitation over China.The variable geopotential height at 500 hPa(GH5)over East Asia,which was obtained from National Centers for Environmental Prediction’s Coupled Forecast System(NCEP CFS),was used as one predictor for the scheme.The preceding sea ice concentration(SIC)signal obtained from observed data over high latitudes of the Northern Hemisphere was chosen as an additional predictor.This downscaling scheme showed significantly improvement in predictability over the original CFS general circulation model(GCM)output in cross validation.The multi-year average spatial anomaly correlation coefficient increased from–0.03 to 0.31,and the downscaling temporal root-mean-square-error(RMSE)decreased significantly over that of the original CFS GCM for most China stations.Furthermore,large precipitation anomaly centers were reproduced with greater accuracy in the downscaling scheme than those in the original CFS GCM,and the anomaly correlation coefficient between the observation and downscaling results reached～0.6 in the winter of 2008.

Corrected Statistical Energy Analysis Model in a Non-Reverberant Acoustic Space

Statistical Energy Analysis(SEA)is a well-known method to analyze the flow of acoustic and vibration energy in a complex structure.This study investigates the application of the corrected SEA model in a non-reverberant acoustic space where the direct field component from the sound source dominates the total sound field rather than a diffuse field in a reverberant space which the classical SEA model assumption is based on.A corrected SEA model is proposed where the direct field component in the energy is removed and the power injected in the subsystem considers only the remaining power after the loss at first reflection.Measurement was conducted in a box divided into two rooms separated by a partition with an opening where the condition of reverberant and non-reverberant can conveniently be controlled.In the case of a non-reverberant space where acoustic material was installed inside the wall of the experimental box,the signals are corrected by eliminating the direct field component in the measured impulse response.Using the corrected SEA model,comparison of the coupling loss factor(CLF)and damping loss factor(DLF)with the theory shows good agreement.

Photon pair source via two coupling single quantum emitters

We study the two coupling two-level single molecules driven by an external field as a photon pair source. The probability of emitting two photons, P2, is employed to describe the photon pair source quality in a short time, and the correlation coefficient RAB is employed to describe the photon pair source quality in a long time limit. The results demonstrate that the coupling single quantum emitters can be considered as a stable photon pair source.

Modeling the Tropical Pacific Ocean Using a Regional Coupled Climate Model

A high-resolution tropical Pacific general circulation model （GCM） coupled to a global atmospheric GCM is described in this paper. The atmosphere component is the 5°× 4° global general circulation model of the Institute of Atmospheric Physics （IAP） with 9 levels in the vertical direction. The ocean component with a horizontal resolution of 0.5°, is based on a low-resolution model （2° × 1° in longitude-latitude）. Simulations of the ocean component are first compared with its previous version. Results show that the enhanced ocean horizontal resolution allows an improved ocean state to be simulated; this involves （1） an apparent decrease in errors in the tropical Pacific cold tongue region, which exists in many ocean models, （2） more realistic large-scale flows, and （3） an improved ability to simulate the interannual variability and a reduced root mean square error （RMSE） in a long time integration. In coupling these component models, a monthly ＂linear-regression＂ method is employed to correct the model＇s exchanged flux between the sea and the atmosphere. A 100-year integration conducted with the coupled GCM （CGCM） shows the effectiveness of such a method in reducing climate drift. Results from years 70 to 100 are described. The model produces a reasonably realistic annual cycle of equatorial SST. The large SSTA is confined to the eastern equatorial Pacific with little propagation. Irregular warm and cold events alternate with a broad spectrum of periods between 24 and 50 months, which is very realistic. But the simulated variability is weaker than the observed and is also asymmetric in the sense of the amplitude of the warm and cold events.

Couple analyzing the acoustic emission characters from hard composite rock fracture

Rock mass is fractured media. Its fracture is a nonlinear process. Theaccumulation of acoustic emission (AF) is closely related to the degree of damage. The dynamicsproblem is simply described based on the non-equilibrium statistical theory of crack evolvement,trying to use the hybrid analysis of the statistical theory and scan electron microscopy (SEM), thecharacters of AE signals from rock damage in a mined-out area is synthetically analyzed andevaluated. These provide an evidence to reverse deduce and accurately infer the position of rockfracture for dynamical hazard control.

The space-time coupling statistical model of reverberation from moving platforms

The space-time coupling characteristic of reverberation is one of key problems in the range of reverberation suppression with space-time processing methods.Traditional methods are not based on statistical characteristics of reverberation and not suitable to analyze the space-time coupling characteristics of reverberation in dealing with problems of reverberation extensions in the actual sea environment and non-ideal arrays.The space-time coupling relationship of moving platforms is deduced and then its space-time coupling statistical model is presented.The model describes the space-time coupling law of reverberation under the conditions as complex acoustic reverberation environments and an arbitrarily specified array.The mathematical expressions of space-time coupling relationship are described when the arrays have ideal narrow beams.The space-time distribution laws of reverberation from moving platforms are shown clearly by the analytical results and computer simulations,which validates the statistical model above.The space-time distribution law of reverberation from an uniform linear array(ULA),which is a non-ideal array,is also calculated by numerical methods.It is shown that the space-time distribution law of reverberation from any actual array can be acquired with the statistical model,and to support theoretically for reverberation suppression algorithms and systems design based on space-time processing.

Morphological parameters of both surfaces of coupled joint

Twenty one joints were made with Brazilian tests and each surface was scanned by the Talysurf CLI 2000. Morphological characteristics of joint surface were quantified by statistical and textural parameters. By the contrast of these parameters between both sides of each coupled joint, the following conclusions are drawn. The upper and lower surfaces of coupled joints have approximately equal values of Sp（maximum height of joint surface）, Sa（arithmetic mean height of joint surface） and Sq（root mean square height of joint surface）, but the Ssk（skewness of the height distribution of joint surface） values of the two surfaces of a coupled joint are different, one is positive while the other is negative. The Saj（auto-correlation length） parameter values of both surfaces of each coupled joint are quite close, and the S^（texture aspect ratio） values have the same situation to the Sal parameter, but the same parameters of different surfaces have big differences which illustrates its own characteristics of each joint. The two surfaces of each coupled joint have similar values of θp （mean profile angle） which can be used to deduce the value of θp each other.

Experimental and simulation studies on similitude design method for shock responses of beam-plate coupled structure

The similitude theory helps to understand the physical behaviors of large structures through scaled models. Several papers have studied the similitude of shock issues. However, the dynamic similitude for shock responses of coupled structures is rarely incorporated in open studies. In this paper, scaling laws are derived for the shock responses and spectra of coupled structures. In the presented scaling laws, the geometric distortion and energy loss are considered. The ability of the proposed scaling laws is demonstrated in the simulation and experimental cases. In both cases, the similitude prediction for the prototype's time-domain waveform and spectrum is conducted with the scaled model and scaling laws. The simulation and experimental cases indicate that the predicted shock responses and spectra agree well with those of the prototype, which verifies the proposed scaling laws for predicting shock responses.

基于统计指标的曲线桥支座脱空病害识别方法

为快速评估曲线连续梁桥支座健康状态,提出了基于时程统计指标的桥梁支座脱空病害识别方法。首先,提取行车激励下桥面测点加速度信号的20个时程统计指标,通过概率统计的方式,得出各统计指标的置信区间;其次,根据各时程统计指标对支座脱空的敏感程度不同,采用熵值法确定各统计指标的权重分配值;最后,根据各测点异常指标数计算损伤指数,综合判断测点附近支座是否出现脱空病害。为验证方法的有效性,以某3×25 m曲线连续梁桥为工程背景,建立车桥耦合动力学模型进行分析验证。结果表明:该方法可以准确识别脱空支座所在位置,并且可以有效识别较小的损伤;相比于中间支座脱空,时程统计指标对端支座脱空更为敏感。

波浪耦合作用下浮式风机非线性系统的统计线性化方法及其在振动控制中的应用

针对海上浮式风机既有分析方法难以高效率地预测其随机动力响应这一问题,提出了一种基于统计线性化算法的波浪耦合作用下浮式风机非线性系统的随机响应快速计算方法,并对其在浮式风机振动控制中的应用进行了研究。以Spar型海上浮式风机为对象,基于拉格朗日方程建立了其4-DOF的波浪耦合作用下的非线性模型,并验证了所建模型的准确性。在所建立的非线性模型基础上,提出了基于统计线性化算法的Spar型浮式风机随机振动分析方法,并从多方面对该方法进行了验证,结果表明该方法能将计算效率提升4,5个数量级,且具有足够精度。将该方法应用于浮式风机振动控制中,高效率地实现受TMD控制下的风机的控制参数优化和性能分析,得到了TMD的最优控制参数,发现TMD对浮式风机的振动控制效果有随海况等级的提高逐步降低的趋势。所提出方法兼具高精度、高效率和在不同海况下的普适性,同时也为海上浮式风机的设计优化、疲劳分析、可靠性验算等基于统计特性的研究提供了一种高效的分析方法。

不同品种生菜的多酚、黄酮差异比较与抗氧化活性

生菜富含多种酚酸、黄酮类化合物,是获取膳食多酚的良好食物来源。本研究对50个不同品种(34种绿色品种和16种红色品种)生菜中的总酚、总黄酮含量及其抗氧化能力进行测定,同时采用超高效液相色谱-四极杆-飞行时间质谱法和超高效液相色谱法对生菜中17种特征酚酸和黄酮类化合物进行鉴定及含量测定,再结合多元统计分析进行分类和相关性分析。结果表明,红色品种生菜的总酚、总黄酮含量及抗氧化能力高于绿色品种生菜;50种生菜中鉴定出绿原酸、咖啡酸、异绿原酸A/B、菊苣酸、木犀草素-7-O-β-D-葡萄糖醛酸苷、槲皮素-3-O-葡萄糖酸苷和槲皮素-3-O-葡萄糖苷7种多酚类化合物,整体在红色品种生菜中含量更高。多元统计分析结果表明绿原酸、木犀草素-7-O-β-D-葡萄糖醛酸苷和槲皮素-3-O-葡萄糖苷与抗氧化能力的相关性较高。综上,G21K104、W3088、H20K6457等5个红色新品种及商业种,G21K212、G21K117等4个绿色新品种为高抗氧化活性生菜品种。本研究可为生菜育种、种质资源创新和营养健康、功能性产品开发提供参考依据。

基于损伤耦合演化过程的黏土-结构物界面统计损伤本构模型

为了评估粗糙度对土与结构物界面强度特性的影响,首先,开展不同法向应力条件下黏土和不同粗糙度黏土-结构物界面强度的直剪试验,分析了土体剪切面强度和界面强度的相互关系;其次,利用图像处理软件分析黏土-结构物界面的剪切机理,提出了考虑结构物表面粗糙度影响的界面损伤耦合演化过程;第三,引入考虑界面粗糙度影响的等效初始损伤因子,基于连续损伤理论和统计强度理论建立了考虑界面损伤耦合演化过程的黏土-结构物界面统计损伤本构模型;最后,结合室内试验结果验证了模型适用性。研究结果表明:在相同法向应力条件下,界面粗糙度越大,界面强度越接近土体强度;界面强度与结构物表面粗糙度呈幂函数关系增加,其增长速率随结构物表面粗糙度增加而降低;黏土-结构物界面剪切全过程的损伤演化过程可分为等效初始损伤阶段和加载损伤阶段,其中,等效初始损伤阶段受界面粗糙度影响,加载损伤包括受荷损伤和耦合损伤。本文模型所得结果与试验结果的吻合度较高,能较好地反映黏土与结构物界面损伤本构特征。

数字普惠金融对共同富裕的影响及其区域异质性——基于富裕、平等和共享协同的视角

从系统观念出发阐释共同富裕内涵并构建与测度了包含富裕度、平等度与共享度子系统的共同富裕指数,深入分析了数字普惠金融影响共同富裕的理论机制,基于2011—2020年的省级面板数据利用GMM方法进行了实证检验。研究发现,数字普惠金融均显著提升了富裕度、平等度、共享度,有利于促进全体人民共同富裕,不同稳健性结果均支持这一结论。数字普惠金融显著地促进了共同富裕子系统的综合协调与良好耦合,体现了从系统视角协同促进共同富裕的必要性。异质性分析表明,数字普惠金融对共同富裕的促进效应在东部更大,存在随时间递减的时变特征,覆盖广度、使用深度与数字化水平的促进效应依次由大变小。

Elemental Quantitative Distribution and Statistical Analysis on Cross Section of Stainless Steel Sheet by Laser Ablation Inductively Coupled Plasma Mass Spectrometry

An innovative application of laser ablation inductively coupled plasma mass spectrometry （LA-ICP-MS） technique in illustrating elemental distributions on stainless steel sheets was presented. The technique proved to be a systematic and accurate ap- proach in producing visual images or maps of elemental distributions at cross-sectional surface of a stainless steel sheet. Two stain- less steel sheets served as research objects： 3 mm×l 300 mm hot-rolled stainless steel plate and 1 mm×l 260 mm cold-rolled plate. The cross-sectional surfaces of the two samples at 1/4 position along the width direction were scanned （raster area -44 mm2 and 11 mm2） with a focused laser beam （wavelength 213 nm, diameter of laser crater 100 μm, and laser power 1.6 mJ） in a laser abla- tion chamber. The laser ablation system was coupled to a quadrupole ICP-MS, which made the detection of ion intensities of 27A1＋, 44Ca＋, 47Ti-, 55Mn＋ and 56Fe＋ within an area of interest possible. One-dimensional （ID） content line distribution maps and two- dimensional （2D） contour maps for specific positions or areas were plotted to indicate the element distribution of a target area with high accuracy. Statistic method was used to analyze the acquired data by calculating median contents, maximum segregation, sta- tistic segregation and content-frequency distribution.

MONOTONE COUPLING AND STOCHASTIC ORDERING OF ORDER STATISTICS

ＭＯＮＯＴＯＮＥＣＯＵＰＬＩＮＧＡＮＤＳＴＯＣＨＡＳＴＩＣＯＲＤＥＲＩＮＧＯＦＯＲＤＥＲＳＴＡＴＩＳＴＩＣＳ￥ＨＵＴａｉｚｈｏｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＵｎｉｖｅｒｓｉｔｙｏｆＳｃｉｅｎｃｅａｎｄＴｅｃｈｎｏｌｏｇｙｏｆＣ...

A thermo-mechanical damage constitutive model for deep rock considering brittleness-ductility transition characteristics

This paper developed a statistical damage constitutive model for deep rock by considering the effects of external load and thermal treatment temperature based on the distortion energy.The model parameters were determined through the extremum features of stress−strain curve.Subsequently,the model predictions were compared with experimental results of marble samples.It is found that when the treatment temperature rises,the coupling damage evolution curve shows an S-shape and the slope of ascending branch gradually decreases during the coupling damage evolution process.At a constant temperature,confining pressure can suppress the expansion of micro-fractures.As the confining pressure increases the rock exhibits ductility characteristics,and the shape of coupling damage curve changes from an S-shape into a quasi-parabolic shape.This model can well characterize the influence of high temperature on the mechanical properties of deep rock and its brittleness-ductility transition characteristics under confining pressure.Also,it is suitable for sandstone and granite,especially in predicting the pre-peak stage and peak stress of stress−strain curve under the coupling action of confining pressure and high temperature.The relevant results can provide a reference for further research on the constitutive relationship of rock-like materials and their engineering applications.