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Identifying Neighborhood Effects on Geohazard Adaptation in Mountainous Rural Areas of China:A Spatial Econometric Model

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International Journal of Disaster Risk Science 2023年第6期14卷 919-931页

作者： li Peng Jing Tan College of Geography and Resources Sichuan Normal UniversityChengdu 610101China School of Public Policy and Administration Chongqing UniversityChongqing 400044China Center for Public Economics&Public Policy Chongqing UniversityChongqing 400044China

In mountainous rural settlements facing the threat of geohazards,local adaptation is a self-organizing process influenced by individual and group behaviors.Encouraging a wide range of local populations to embrace geohazard adaptation strategies emerges as a potent means of mitigating disaster risks.The purpose of this study was to investigate whether neighbors influence individuals'adaptation decisions,as well as to unravel the mechanisms through which neighborhood effects exert their influence.We employed a spatial Durbin model and a series of robustness checks to confirm the results.The dataset used in this research came from a face-to-face survey involving 516 respondents residing in 32 rural settlements highly susceptible to geohazards.Our empirical results reveal that neighborhood effects are an important determinant of adaptation to geohazards.That is,a farmer's adaptation decision is influenced by the adaptation choices of his/her neighbors.Furthermore,when neighbors adopt adaptation strategies,the focal individuals may also want to adapt,both because they learn from their neighbors'choices(social learning)and because they tend to abide by the majority's choice(social norms).Incorporating neighborhood effects into geohazard adaptation studies offers a new perspective for promoting disaster risk reduction decision making.

关键词： Disaster risk reduction Geohazard adaptation Neighborhood effects Rural China Spatial Durbin model(SDM)

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风机安装结构随机振动分析与优化

家电科技 2015年第8期 68-70页

作者：李鹏珠海格力电器股份有限公司广东珠海519070

本文通过随机振动和模态实验,对风机系统安装结构进行了损坏评估和原因分析;针对分析原因,进行了风机结构随机振动的CAE分析、评估和优化,确定了风机系统安装结构的优化方案;结合CAE分析和随机振动实验,进行了其结构分析和验证,实验表... 详细信息

本文通过随机振动和模态实验,对风机系统安装结构进行了损坏评估和原因分析;针对分析原因,进行了风机结构随机振动的CAE分析、评估和优化,确定了风机系统安装结构的优化方案;结合CAE分析和随机振动实验,进行了其结构分析和验证,实验表明优化结构大大提高了风机系统刚度性能,避免了道路运输中的产品损坏。

关键词：随机振动 PSD 模态实验

Amino acid nutrition and metabolism in domestic cats and dogs

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畜牧与生物技术杂志:英文版 2023年第5期14卷 1777-1797页

作者： peng li Guoyao Wu North American Renderers Association AlexandriaVirginia 22314USA Department of Animal Science Texas A&M UniversityCollege StationTX 77843USA

Domestic cats and dogs are carnivores that have evolved differentially in the nutrition and metabolism of amino acids.This article highlights both proteinogenic and nonproteinogenic amino acids.Dogs inadequately synthesize citrulline(the precursor of arginine)from glutamine,glutamate,and proline in the small intestine.Although most breeds of dogs have potential for adequately converting cysteine into taurine in the liver,a small proportion(1.3%-2.5%)of the Newfoundland dogs fed commercially available balanced diets exhibit a deficiency of taurine possibly due to gene mutations.Certain breeds of dogs(e.g.,golden retrievers)are more prone to taurine deficiency possibly due to lower hepatic activities of cysteine dioxygenase and cysteine sulfinate decarboxylase.De novo synthesis of arginine and taurine is very limited in cats.Thus,concentrations of both taurine and arginine in feline milk are the greatest among domestic mammals.Compared with dogs,cats have greater endogenous nitrogen losses and higher dietary requirements for many amino acids(e.g.,arginine,taurine,cysteine,and tyrosine),and are less sensitive to amino acid imbalances and antagonisms.Throughout adulthood,cats and dogs may lose 34%and 21%of their lean body mass,respectively.Adequate intakes of high-quality protein(i.e.,32%and 40%animal protein in diets of aging dogs and cats,respectively;dry matter basis)are recommended to alleviate aging-associated reductions in the mass and function of skeletal muscles and bones.Pet-food grade animal-sourced foodstuffs are excellent sources of both proteinogenic amino acids and taurine for cats and dogs,and can help to optimize their growth,development,and health.

关键词： Animal-sourced foodstuffs Cats Dogs Health Metabolism Nutrition

Progress in Modeling Neural Tube Development and Defects by Organoid Reconstruction

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Neuroscience Bulletin 2022年第11期38卷 1409-1419页

作者： peng li Yongchang Chen State Key Laboratory of Primate Biomedical Research and Institute of Primate Translational Medicine Kunming University of Science and TechnologyKunming 650500China Yunnan Key Laboratory of Primate Biomedical Research Kunming 650500China

It is clear that organoids are useful for studying the structure as well as the functions of organs and tissues;they are able to simulate cell-to-cell interactions,symmetrical and asymmetric division,proliferation,and migration of different cell groups.Some progress has been made using brain organoids to elucidate the genetic basis of certain neurodevelopmental disorders.Such as Parkinson’s disease and Alzheimer’s disease.However,research on organoids in early neural development has received insufficient attention,especially that focusing on neural tube precursors.In this review,we focus on the recent research progress on neural tube organoids and discuss both their challenges and potential solutions.

关键词： Neural tube Organoid Neural tube defect

Sequence Stratigraphy of the Lower Cretaceous Uraniferous Measures and Mineralization of the Sandstone-hosted Tamusu Large Uranium Deposit,North China

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Acta Geologica Sinica(English Edition) 2022年第1期96卷 167-192页

作者： liU Bo SHI Zhiqiang peng Yunbiao ZHANG pengfei li Peng Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China Geologic Party No.208 China Nuclear GeologyBaotouInner Mongolia 014010China

The Bayingobi basin is the Mesozoic-Cenozoic basin in North China in which the Tamusu uranium deposit is located.The ore-target layer of the deposit is the Lower Cretaceous Bayingobi Formation,which developed as a fan deltashallow lacustrine deposit.The distributary channel sand body of the fan delta plain and the underwater distributary channel sand body of the fan delta front formed a favorable uranium reservoir,so the study of sequence stratigraphy is extremely important to understanding the genesis of uranium deposits.On the basis of field investigation and a large number of borehole logs,the high resolution sequence stratigraphy of the Lower Cretaceous is divided and the system tracts of different periods are established.The relationship between deposition,interlayer oxidation and uranium enrichment is discussed.The Lower Cretaceous Bayingobi Formation can be divided into two fourth-order sequences(Sq1 and Sq2).The lower member of the Bayingobi Formation is referred to as Sq1,which is composed of a falling-stage system tract(FSST)on top.On the other hand,the upper member of the Bayingobi Formation is referred to as Sq2,which is composed of a lowstand system tract(LST),transgressive system tract(TST)and highstand system tract(HST).The lowstand system tract forms a favorable stratigraphic structure(mud-sand-mud formation)with the lacustrine mudstone of the overlying transgressive system tract,that is conducive for the migration of uranium-bearing oxygen water.The organic matter and pyrite in the fan delta sand body,as well as the dark mudstone in the distributary bay,provided a reducing medium for uranium mineralization.The ore body mainly occurs in the distributary channel,underwater distributary channel or the mouth bar of the fan delta.As a result of the moderate thickness,high permeability,favorable barrier and rich reducing medium,the rich ore body mainly occurs in the underwater distributary channel and mouth bar sand body of the delta front.Based on study of the sequence stratigraphy,the model of the se

关键词： Bayingobi Formation sequence stratigraphy fan delta uranium mineralization Tamusu uranium deposit

Lowly Fused Non-Fullerene Acceptors Towards Efficient Organic Solar Cells Enabled by Isomerization

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Chinese Journal of Polymer Science 2022年第8期40卷 928-936,I0009页

作者： Min Deng Xiao-peng Xu li-Yang Yu Rui-peng li Qiang peng School of Chemical Engineering Key Laboratory of Green Chemistry and Technology of Ministry of Education and State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065China National Synchrotron light Source II Brookhaven National LabSuffolkUptonNY11973USA

Two lowly fused non-fullerene acceptors(NFAs)with isomeric structures,named as BTP-out-4F and BTP-in-4F,were developed by tailoring the fused 7-ring central core of Y6 into a lowly fused 5-ring linked with two octyloxythiophene bridges.BTP-out-4F with octyloxy side chains away from the central core exhibited large steric hindrance that restrained the rotational freedom between the thiophene bridge and end group but maintained free rotation between the central core and the thiophene bridge.In contrast,BTP-in-4F with octyloxy side chains close to the central core had much lower rotation freedom due to the non-covalent S⋯O interactions locked the central core,thiophene bridge and end group simultaneously,making BTP-in-4F have higher molecular crystallinity.On the other hand,the optical properties,energy levels and the blend morphology properties were significantly influenced,leading to distinctive photovoltaic performances.BTP-out-4F formed favorable energy level alignment and morphology when matching with PBDB-T donor,thus its device realized a much higher PCE of 13.32%,which was over 13 times than that of BTP-in-4F based device(PCE=0.97%).

关键词： Polymer solar cells Nonfullerene acceptors Lowly fused Structural isomerization Confirmation lock

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李澎辨治功能性便秘经验

辽宁中医杂志 2023年第3期50卷 21-23页

作者：马亚平李澎天津中医药大学第一附属医院天津300193 国家中医针灸临床医学研究中心天津300193

功能性便秘归属于中医学“后不利”范畴,李澎主任认为本病的病机为大肠传导失司,其病变脏腑主要责之于肝、脾、胃、肾功能失调,病位在大肠,临床治疗多从肝、脾、胃、肾入手,治疗时首分虚证、实证。虚证多为阳气亏虚型,治宜温阳通便。实... 详细信息

功能性便秘归属于中医学“后不利”范畴,李澎主任认为本病的病机为大肠传导失司,其病变脏腑主要责之于肝、脾、胃、肾功能失调,病位在大肠,临床治疗多从肝、脾、胃、肾入手,治疗时首分虚证、实证。虚证多为阳气亏虚型,治宜温阳通便。实证多为肝脾不和型,治宜疏肝健脾,清热理气;胃肠积热型,治宜泻热导滞,润肠通便。另外,李师勤求古训,阅读古籍,发现行间穴在功能性便秘中之妙用,兹作以简单介绍。

关键词：功能性便秘经验行间

Stability assessment of tree ring growth of Pinus armandii Franch in response to climate change based on slope directions at the Lubanling in the Funiu Mountains,China

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Journal of Forestry Research 2024年第2期35卷 197-208页

作者： Jinkuan li Jianfeng peng Xiaoxu Wei Meng peng Xuan li Yameng liu Jiaxin li College of Geography and Environmental Science Henan UniversityKaifeng 475004People’s Republic of China Key Laboratory of Earth System Observation and Simulation of Henan Province Kaifeng 475004People’s Republic of China

Global warming will affect growth strategies and how trees will adapt.To compare the response of tree radial growth to climate warming in different slope directions,samples of Pinus armandii Franch were collected and treering chronologies developed on northern and western slopes from the Lubanling in the Funiu Mountains.Correlation analyses showed that two chronologies were mainly limited by temperatures in the previous June–August and the combination of temperatures and moisture in the current May–July.The difference of the climate response to slopes was small but not negligible.Radial growth of the LBL01 site on the northern slope was affected by the combined maximum and minimum temperatures,while that of the LBL02 site was affected by maximum temperatures.With regards to moisture,radial growth of the trees on the north slope was influenced by the relative humidity in the current May–July,while on the western slope,it was affected by the relative humidity in the previous June–August,the current May–July and the precipitation in the current May–July.With the change in climate,the effects of the main limiting factors on growth on different slopes were visible to a certain extent,but the differences in response of trees on different slopes gradually decreased,which might be caused by factors such as different slope directions and the change in diurnal temperature range.These results may provide information for forest protection and ecological construction in this region,and a scientific reference for future climate reconstruction.

关键词： Tree ring width Lubanling Pinus armandii Franch Slope direction Climate response

An analytical analysis for the mechanical performance of fully-grouted rockbolts based on the exponential softening model

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International Journal of Mining Science and Technology 2022年第5期32卷 981-995页

作者： Zhongwen Yue Akang li peng Wang peng Wang Department of Mechanics and Civil Engineering China University of Mining and Technology-BeijingBeijing 100083China Pan-China Construction Group Co. Ltd.Beijing 100070China

This paper presented a novel bond-slip model to better reveal the mechanical behavior of the bolt-grout interface for fully-grouted rockbolts under tensile loads by considering the non-linear response in the softening stage.The exponential decay function is adopted for describing the non-linear response in the softening stage.Based on the improved bond-slip model,the corresponding analytical solutions for the interfacial shear stress and the axial force of the bolt under different loading stages are solved.Then,the validity of this proposed model was verified by comparing with the experimental results.The results show that compared with the linear softening model,the proposed model is more suitable for predicting the mechanical performance of fully-grouted rockbolts.Finally,a series of parametric studies are conducted to explore the effect of model parameters on the mechanical properties of fully-grouted rockbolts.The results indicate that compared with the anchor length,the bolt diameter and the bond strength of the bolt-grout interface have a significance influence on the ultimate load of bolt,especially for the elastic and softening stage.Moreover,it can be found that using the linear softening model maybe overestimates the supporting performance of grouted bolt,resulting in an unsafe design for bolt.

关键词： Fully-grouted rockbolts Non-linear response Bond-slip model Anchor length Analytical solutions