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Relationship between Atmospheric Heat Source over the Tibetan Plateau and Precipitation in the Sichuan–Chongqing Region during Summer

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Journal of Meteorological Research 2017年第3期31卷 555-566页

作者： Xin lai Yuanfa GONG College of Atmospheric Sciences Chengdu University of Information Technology (CUIT)/Plateau Atmosphere and Environment Key Laboratory of Sichuan Provinceand Joint Laboratory of Climate and Environment Change of CUIT

NCEP-NCAR reanalysis data and a 47-yr daily precipitation dataset from a network of 42 rain gauges are used to analyze the atmospheric heat source （〈Q1〉） anomaly over the Tibetan Plateau （TP） and its influence on the summer precipitation anomaly in the Sichuan-Chongqing region. Results show that the vertical advection of 〈Ql〉 over the central TP is a major factor affecting summer precipitation in the Sichuan-Chongqing region. When the vertical ad- vection of〈Q1〉 over the central TP is strengthened, the South Asian high shifts further than normal to the south and east, the western Pacific subtropical high shifts further than normal to the south and west, and the Indian low weak- ens. This benefits the transport of warm moist air from the low latitude oceans to the Sichuan-Chongqing region. Correspondingly, in the high latitudes, two ridges and one trough form, which lead to cool air moving southward. These two air masses converge over the Sicbuan -chongqing region, leading to significant precipitation. In contrast, when the vertical advection of 〈Q1〉 over the central TP is weakened, the South Asian high moves to the north and west, the subtropical high moves eastward and northward, and the Indian low strengthens. This circulation pattern is unfavorable for warm air advection from the south to the Sichuan-Chongqing region, and the cool air further north cannot move southward because of the presence of two troughs and one ridge at high latitude. Thus, ascent over the Sichuan-Chongqing region is weakened, resulting in less precipitation.

关键词： Tibetan Plateau atmospheric heating source/sink Sichuan-Chongqing region precipitation variability

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Mathematical modeling of cancer treatment with radiation and PD-L1 inhibitor

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Science China Mathematics 2020年第3期63卷 465-484页

作者： Xiulan lai Avner Friedman Institute for Mathematical Sciences Renmin University of ChinaBeijing 100872China Mathematical Bioscience Institute&Department of Mathematics Ohio State UniversityColumbusOH 43210USA

Radiation therapy is a longstanding cancer treatment. More recently, it has been demonstrated that radiation therapy(RT) elicits anti-cancer immune response. For this reason, there is a growing interest in combining RT with immunotherapy, specifically with checkpoint inhibitors such as anti-CTLA-4 and anti-PDL1. In the present paper, we develop a mathematical model of combination therapy with RT and *** model is used to compare different schedules in clinical trials. Simulations of the model show that applying both RT and anti-PD-L1 at the same week has more benefits than applying them in separate adjacent ***, applying anti-PD-L1 before RT has more benefits than applying RT before anti-PD-L1.

关键词： mathematical model anti-PD-L1 radiotherapy combination therapy scheduling

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Synthesis of novel cyclohexanediol-derived chiral phosphite ligands and their application in the Cu-catalyzed conjugate addition of organozinc to cyclic enones

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Chinese Chemical Letters 2016年第2期27卷 271-276页

作者： Zeng-Bo Pang Hai-Feng Li lai-lai Wang State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China University of Chinese Academy of Sciences Beijing 100039 China

A series of novel chiral diphosphite ligands have been synthesized from（1R,2R）-trans-1,2-cyclohexanediol,（1S,2S）-trans-1,2-cyclohexanediol, racemic trans-1,2-cyclohexanediol and chlorophosphoric acid diary ester, and were successfully employed in the Cu-catalyzed asymmetric 1,4-conjugate addition of diethylzinc to cyclohexenone with up to 99% ee. It was found that ligand 1,2-bis[（R）-1,10-binaphthyl-2,2＇-diyl]phosphitecyclohexanediol 6a derived from racemic diol skeleton can show similar catalytic performance compared with ligand（1R,2R）-bis[（R）-1,1＇-binaphthyl-2,2＇-diyl]phosphitecyclohexanediol 6a＇ derived from enantiopure starting material. A significant dependence of stereoselectivity on the type of enone and the ring size of the cyclic enone was observed. Moreover, the configuration of the products was mainly determined by the configuration of the binaphthyl moieties of diphosphite ligands in the 1,4-addition of cyclic enones.

关键词： Racemic and chiral cyclohexanedio Phosphite ligands Organozinc Cyclic enones Cu-catalyzed conjugate addition

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Rarefaction Wave Interaction and Shock-Rarefaction Composite Wave Interaction for a Two-Dimensional Nonlinear Wave System

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Chinese Annals of Mathematics,Series B 2021年第1期42卷 135-150页

作者： Geng lai Sisi XIE Department of Mathematics Shanghai UniversityShanghai 200444China

In order to construct global solutions to two-dimensional(2 D for short)Riemann problems for nonlinear hyperbolic systems of conservation laws,it is important to study various types of wave *** paper deals with two types of wave interactions for a 2 D nonlinear wave system with a nonconvex equation of state:Rarefaction wave interaction and shock-rarefaction composite wave *** order to construct solutions to these wave interactions,the authors consider two types of Goursat problems,including standard Goursat problem and discontinuous Goursat problem,for a 2 D selfsimilar nonlinear wave *** classical solutions to these Goursat problems are obtained by the method of *** solutions constructed in the paper may be used as building blocks of solutions of 2 D Riemann problems.

关键词： Nonlinear wave system Rarefaction wave Shock-rarefaction composite wave Wave interaction Characteristic decomposition

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Epigenetics of cutaneous T-cell lymphoma:biomarkers and therapeutic potentials

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Cancer Biology & Medicine 2021年第1期18卷 34-51页

作者： Pan lai Yang Wang Department of Dermatology and Venereology Peking University First HospitalBeijing Key Laboratory of Molecular Diagnosis on DermatosesNational Clinical Research Center for Skin and Immune DiseasesBeijing 100034China

Cutaneous T-cell lymphomas(CTCLs)are a heterogeneous group of skin-homing non-Hodgkin *** are limited options for effective treatment of patients with advanced-stage CTCL,leading to a poor survival *** plays a pivotal role in regulating gene expression without altering the DNA *** alterations are involved in virtually all key cancerassociated pathways and are fundamental to the genesis of *** recent years,the epigenetic hallmarks of CTCL have been gradually elucidated and their potential values in the diagnosis,prognosis,and therapeutic intervention have been *** this review,we summarize the current knowledge of the best-studied epigenetic modifications in CTCL,including DNA methylation,histone modifications,micro RNAs,and chromatin *** epigenetic regulators are essential in the development of CTCL and provide new insights into the clinical treatments of this refractory disease.

关键词： Epigenetics cutaneous T-cell lymphoma DNA methylation histone modification micro RNA chromatin-remodeling complex

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Evaluation on Stability of Stope Structure Based on Nonlinear Dynamics of Coupling Artificial Neural Network

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Journal of University of Science and Technology Beijing 2002年第1期9卷 1-4页

作者： Meifeng Cai Xingping lai Civil and Environmental Engineering School University of Science and Technology BeijingBeijjing 100083China Xi'an Science and Technology University Shanxi Strata Control Key LaboratoryXi'an 710054China

The nonlinear dynamical behaviors of artificial neural network (ANN) and their application to science and engineering were summarized. The mechanism of two kinds of dynamical processes, i.e. weight dynamics and activation dynamics in neural networks, and the stability of computing in structural analysis and design were stated briefly. It was successfully applied to nonlinear neural network to evaluate the stability of underground stope structure in a gold mine. With the application of BP network, it is proven that the neuro-com- puting is a practical and advanced tool for solving large-scale underground rock engineering problems.

关键词： coupling neural network nonlinear dynamics structural stability stope parameters

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珠江三角洲城市群留鸟多样性格局及其驱动机制

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中山大学学报（自然科学版）（中英文） 2025年第1期64卷 218-227页

作者：叶俊宏刘珍环杨帆魏莱周义广东省粤北岩溶区碳水耦合野外科学观测研究站/中山大学地理科学与规划学院广东广州510006

鸟类是反映城市生境和生物多样性变化的重要指标,城市鸟类多样性分布格局模拟与预测是当前城市生物多样性保护研究中重点关注的难题。珠江三角洲城市群经历了快速的城市化过程,景观变化显著,给城市生境和生物多样性保护带来了巨大挑战... 详细信息

鸟类是反映城市生境和生物多样性变化的重要指标,城市鸟类多样性分布格局模拟与预测是当前城市生物多样性保护研究中重点关注的难题。珠江三角洲城市群经历了快速的城市化过程,景观变化显著,给城市生境和生物多样性保护带来了巨大挑战。为解析城市鸟类多样性与城市生境之间的空间关联机制,构建“单物种分布预测-物种多样性聚类-多样性的影响归因”的空间综合途径,开展珠江三角洲城市群留鸟空间格局与形成机制研究。结果表明:1)珠江三角洲城市群的87种留鸟构成的多样性与适宜性具有高度的城-乡梯度分布模式;将留鸟的空间适宜性聚类可分为8类,总体上留鸟的中高适宜区占比小于30%。2)结构方程模型的解析可以发现,人类活动显著地正向影响了鸟类多样性的空间分布格局,影响系数介于0.28~1.94;而植被、气候、地形的正向或负向效应差异明显。研究可为城市生物多样性保护,调控鸟类多样性的生境影响因素,开展城市生态建设与管理提供科学依据。

关键词：城市生物多样性鸟类 MaxEnt模型结构方程模型

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Intraday Volume Percentages Forecasting Using a Dynamic SVM-Based Approach

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Journal of Systems Science & Complexity 2017年第2期30卷 421-433页

作者： LIU Xiaotao lai Kin Keung Department of Finance Central China Normal University International Business School Shaanxi Normal University Department of Management Sciences City University of Hong Kong

This paper proposes a dynamic model to forecast intraday volume percentages by decomposing the trade volume into two parts: The average part as the intraday volume pattern and the residual term as the abnormal changes. An empirical test on data spanning half-a-year gold futures and S&P 500 futures reveals that a rolling average of the previous days' volume percentages shows great predictive ability for the average part. An SVM approach with the input pattern consisting of two categories is employed to forecast the residual term. One is the previous days' volume percentages in the same time interval and the other is the most recent volume percentages. The study shows that this dynamic SVM-based forecasting approach outperforms the other commonly used statistical methods and enhances the tracking performance of a VWAP strategy greatly.

关键词： Intraday volume percentages principal component decomposition SVM VWAP.

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Stabilization control of a hovering model insect:lateral motion

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Acta Mechanica Sinica 2011年第5期27卷 823-832页

作者： Yan-lai Zhang Mao Sun Ministry-of-Education Key Laboratory of Fluid Mechanics Beihang University 100191 Beijing China

Our previous study shows that the lateral disturbance motion of a model drone fly does not have inherent stability （passive stability）,because of the existence of an unstable divergence *** drone flies are observed to fly *** active control must be applied to stabilize the *** this study,we investigate the lateral stabilization control of the model drone *** method of computational fluid dynamics is used to compute the lateral control derivatives and the techniques of eigenvalue and eigenvector analysis and modal decomposition are used for solving the equations of *** analysis shows that although inherently unstable,the lateral disturbance motion is *** feeding back the state variables （*** translation velocity,yaw rate,roll rate and roll angle,which can be measured by the sensory system of the insect） to produce anti-symmetrical changes in stroke amplitude and/or in angle of attack between the left and right wings,the motion can be stabilized,explaining why the drone flies can fly stably even if the flight is passively unstable.

关键词： Hovering drone fly Lateral motion Flight stability Stabilization control Modal analysis

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Dynamic flight stability of hovering model insects:theory versus simulation using equations of motion coupled with Navier-Stokes equations

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Acta Mechanica Sinica 2010年第4期26卷 509-520页

作者： Yan-lai Zhang Mao Sun Ministry-of-Education Key Laboratory of Fluid Mechanics Institute of Fluid Mechanics Beihang University 100191 Beijing China

In the present paper, the longitudinal dynamic flight stability properties of two model insects are predicted by an approximate theory and computed by numerical sim- ulation. The theory is based on the averaged model （which assumes that the frequency of wingbeat is sufficiently higher than that of the body motion, so that the flapping wings＇ degrees of freedom relative to the body can be dropped and the wings can be replaced by wingbeat-cycle-average forces and moments）; the simulation solves the complete equations of motion coupled with the Navier-Stokes equations. Comparison between the theory and the simulation provides a test to the validity of the assumptions in the theory. One of the insects is a model dronefly which has relatively high wingbeat frequency （164 Hz） and the other is a model hawkmoth which has relatively low wingbeat frequency （26 Hz）. The results show that the averaged model is valid for the hawkmoth as well as for the dronefly. Since the wingbeat frequency of the hawkmoth is relatively low （the characteristic times of the natural modes of motion of the body divided by wingbeat period are relatively large） compared with many other insects, that the theory based on the averaged model is valid for the hawkmoth means that it could be valid for many insects.

关键词： Insect Hovering Dynamic flight stability Averaged model Equations-of-motion Navier-Stokes simulation

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