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Quantitative analysis of the impact of droughts and floods on internal wars in China over the last 500 years

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Science China Earth Sciences 2017年第12期60卷 2078-2088页

作者： harry F.LEE David D.ZhANG pEI Qing JIA Xin ricci p.h.yue Department of Geography and International Center for China Development Studies The University of Hong Kong School of Geographical Sciences Guangzhou University Department of Social Sciences The Education University of Hong Kong School of Geographic and Oceanographic Sciences Nanjing University

Although many large-N quantitative studies have evidenced the adverse effects of climatic extremes on social stability in China during the historical period, most of them rely on temperature and precipitation as major explanatory variables, while the influence of floods and droughts on social crises is rarely measured. Furthermore, a comparison of the climate-society nexus among different geographic regions and at different temporal scales is missing in those studies. To address this knowledge gap,this study examines quantitatively the influence of floods and droughts on internal wars in three agro-ecological(rice, wheat,and pastoral) regions in China in AD1470–1911. poisson regression and wavelet transform coherence analyses are applied to allow for the non-linear and non-stationary nature of the climate-war nexus. Results show that floods and droughts are significant in driving internal wars in historical China, but are characterized by strong regional variation. In the rice region, floods trigger internal wars at the inter-annual and multi-decadal time scales. In the wheat region, both floods and droughts cause internal wars at the inter-annual and multi-decadal time scales. In the pastoral region, internal wars are associated with floods only at the multi-decadal time scale. In addition, the multi-decadal coherence between hydro-climatic extremes and internal wars in all three of the agro-ecological regions is only significant in periods in which population density is increasing or the upper limit of regional carrying capacity is being reached. The above results imply that the climate-war nexus is mediated by regional geographic factors such as physical environmental setting and population pressure. hence, we encourage researchers who study the historical human-climate relationship to boil down data according to geographic regions in the course of statistical analysis and to examine each region individually in follow-up studies.

关键词： Floods and droughts Climatic extremes Internal wars Wars Social stability Ming-Qing period

Differentiations of geographic distribution and subsistence strategies between Tibetan and other major ethnic groups are determined by the physical environment in hehuang Valley

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Science China Earth Sciences 2019年第2期62卷 412-422页

作者： Xin JIA harry F.LEE Mengchun CUI Guoquan ChENG Yang ZhAO hong DING ricci p.h.yue huayu LU School of Geographic and Oceanographic Sciences Nanjing University College of Earth and Environmental Sciences Lanzhou University Needham Research Institute Department of Geography and Resource Management The Chinese University of Hong Kong School of Marxism Taiyuan University of Technology Department of Geography and International Center for China Development Studies The University of Hong Kong

The people of the Tibetan plateau have received extensive attention from scholars because of their unique adaptability to the low temperature and anoxic environments. however, the Tibetan communities and their habitats in the low-altitude regions of the plateau have rarely been studied in a scientific manner. Based on the extraction of geographic information of 197 towns in the hehuang Valley and on variance analysis, this study examines the habitats and subsistence strategies of the Tibetans and other major ethnic groups in the low-latitude region of the Tibetan plateau. Our statistical results show that the annual average temperature of Tibetan habitats in the hehuang Valley is relatively high. The relatively warm environment of the valley allows the Tibetans in that area to cultivate wheat and barley and raise cattle and sheep—a subsistence strategy significantly different from that of other Tibetans in the high-altitude regions in the Tibetan plateau. In addition, the Tibetan communities in the hehuang Valley include similar agri-pastoral ethnic groups (including hui and Salar), both of which adopt similar subsistence strategies. The agricultural ethnic groups (han and Tu) live in a relatively cool and humid environment facilitating agricultural production, while the agri-pastoral ethnic groups (Tibetan, hui, and Salar) inhabit relatively warm and arid environment in the valley. Due to the lack of agricultural activities, agri-pastoral groups must also engage in animal husbandry to supplement their diet. In the Ando Tibetan region, the subsistence strategies of the ethnic groups are closely related to their physical *** ethnic groups communicate among themselves, integrate, and influence each other, resulting in a diversified culture. This study proves that the habitat variation at a regional scale corresponds significantly to the variation of subsistence strategies. Our findings may further refine knowledge about the human-environmental relationsh

关键词： Tibetan plateau Ethnic group Ethnic geography hehuang Valley Ando Tibetan region

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关于局部诺伊曼等周常数

数学进展 2024年第3期53卷 499-511页

作者：岳文艳张振雷首都师范大学数学科学学院北京100048

本文引入流形中一个相对区域上的相对等周不等式,并说明它等价于相对Sobolev不等式.在倍体积假设条件下,推出了度量球上的经典等周不等式.最后,讨论了该不等式在一些曲率条件下的应用和凯勒—里奇流中的应用.

关键词：相对等周不等式诺伊曼等周常数

On Spiral Waves Arising in Natural Systems

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Communications in Computational physics 2010年第8期8卷 610-622页

作者： D.Bini C.Cherubini S.Filippi A.Gizzi p.E.ricci Istituto per le Applicazioni del Calcolo“M.picone” CNR I-00161 RomeItaly International Center for Relativistic Astrophysics-I.C.R.A. University of Rome“La Sapienza”I-00185 RomeItaly Nonlinear physics and Mathematical Modeling Lab Faculty of EngineeringUniversity Campus Bio-MedicoI-00128 RomeItaly Alberto Sordi Foundation-Research Institute on Aging I-00128 RomeItaly Mathematics Department University of Rome“La Sapienza”I-00185 RomeItaly

Spiral waves appear in many different natural contexts:excitable biological tissues,fungi and amoebae colonies,chemical reactions,growing crystals,fluids and gas eddies as well as in *** the existing theories explain the presence of spirals in terms of nonlinear parabolic equations,it is explored here the fact that selfsustained spiral wave regime is already present in the linear heat operator,in terms of integer Bessel functions of complex *** solutions,even if commonly not discussed in the literature because diverging at spatial infinity,play a central role in the understanding of the universality of spiral *** particular,we have studied how in nonlinear reaction-diffusion models the linear part of the equations determines the wave front appearance while nonlinearities are mandatory to cancel out the blowup of *** spiral wave pattern still requires however at least two cross-reacting species to be physically *** implications of such a results are discussed.

关键词： Reaction-diffusion equations biophysics crystal growth heat transfer

Whole-body heat exposure induces membrane changes in spermatozoa from the cauda epididymidis of laboratory mice

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Asian Journal of Andrology 2010年第4期12卷 591-598页

作者： harsha Wechalekar Brian p. Setchell Eleanor J. peirce Mario ricci Chris Leigh William G. Breed Discipline of Anatomy and pathology School of Medical Sciences Faculty of Health Sciences University of Adelaide Adelaide South Australia 5005 Australia Division of health Sciences University of South Australia City East Campus Adelaide South Australia 5000 Australia

This study was carried out to determine if exposure to hot environmental temperatures had a direct, detrimental effect on sperm quality. For this the effect of whole-body heat exposure on epididymal spermatozoa of laboratory mice was investigated. C57BL/6 mice （n = 7） were housed in a microclimate chamber at 37℃-38℃ for 8 h per day for three consecutive days, while control mice （n = 7） were kept at 23℃-24℃. Cauda epididymal spermatozoa were obtained 16 h after the last heat treatment. The results showed that sperm numbers were similar in the two groups （p = 0.23）, but after heat treatment, a significant reduction in the percentage of motile sperm was present （p 〈 0.0001）. Membrane changes of the spermatozoa were investigated by staining with phycoerythrin （pE）- conjugated Annexin V, which detects exteriorization of phosphotidylserine from the inner to the outer leaflet of the sperm plasma membrane, and 7-aminoactinomycin D （7-AAD）, which binds to the sperm nucleus when the plasma membrane is damaged. The percentage of spermatozoa showing positive staining with Annexin V-pE or 7-AAD or both, was significantly higher （p 〈 0.05） in heat-exposed mice compared with controls. These results show that whole-body heat exposure to 37℃-38℃ induces membrane changes in the epididymal spermatozoa of mice, which may lead to apoptosis.

关键词： laboratory mice sperm membrane damage whole-body heat

helicobacter pylori gamma-glutamyl transpeptidase and its pathogenic role

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World Journal of Gastroenterology 2014年第3期20卷 630-638页

作者： Vittorio ricci Maria Giannouli Marco Romano Raffaele Zarrilli Department of Molecular Medicine Human Physiology SectionUniversity of Pavia Medical School Department of public health Hygiene SectionUniversity of Naples "Federico Ⅱ" Department of Clinical and Experimental Medicine Chair of GastroenterologySecond University of Naples CEINGE Biotecnologie Avanzate

helicobacter pylori(***)gamma-glutamyl transpeptidase(GGT)is a bacterial virulence factor that converts glutamine into glutamate and ammonia,and converts glutathione into glutamate and *** GGT causes glutamine and glutathione consumption in the host cells,ammonia production and reactive oxygen species *** products induce cell-cycle arrest,apoptosis,and necrosis in gastric epithelial *** GGT may also inhibit apoptosis and induce gastric epithelial cell proliferation through the induction of cyclooxygenase-2,epidermal growth factor-related peptides,inducible nitric oxide synthase and *** GGT induces immune tolerance through the inhibition of T cell-mediated immunity and dendritic cell *** effect of GGT on *** colonization and gastric persistence are also discussed.

关键词： helicobacter pylori Gamma-glutamyl transpeptidase Bacterial virulence factor Gastric epithelial cell damage T cell-mediated immunity

Transparent conducting materials discovery using high-throughput computing

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npj Computational Materials 2019年第1期5卷 606-618页

作者： Guillaume Brunin Francesco ricci Viet-Anh ha Gian-Marco Rignanese Geoffroy hautier UCLouvain Institut de la Matière Condensée et des Nanosciences(IMCN)Chemin desÉtoiles 8Louvain-la-Neuve 1348Belgium

Transparent conducting materials(TCMs)are required in many applications from solar cells to transparent *** high performance materials combining the antagonistic properties of transparency and conductivity has been challenging especially for p-type ***,high-throughput ab initio computational screening has emerged as a formidable tool for accelerating materials *** this review,we discuss how this approach has been applied for identifying *** provide a brief overview of the different materials properties of importance for TCMs(e.g.,dopability,effective mass,and transparency)and present the ab initio techniques available to assess *** focus on the accuracy of the methodologies as well as their suitability for high-throughput ***,we review the different high-throughput computational studies searching for new TCMs and discuss their differences in terms of methodologies and main findings.

关键词： transparency conducting suitability

Improved food environments for healthy diets and enhanced nutrition

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Journal of Integrative Agriculture 2019年第7期18卷 1652-1654页

作者： QIN Yong-jun Nathanael pingault Fabio ricci Jessica Fanzo high-Level panel of Experts on Food Security and Nutrition (hLpE) of the UN Committee on World Food Security Rome 00153Italy Johns hopkins University BaltimoreMD 21205USA Shanxi Academy of Agricultural Sciences Taiyuan 030006P.R. China

As illustrated by the high-Level panel of Experts on Food Security and Nutrition of the UN Committee on World Food Security(hLpE 2017),while hunger is on the rise again,malnutrition now takes multiple forms and affects all ***,821 million people are still undernourished (FAO et al.2018),over 2 billion people suffer from micronutrient deficiencies,while overweight and obesity are quickly rising which affects 1.9 billion adults and 41 million children under five.

关键词： micronutrient malnutrition Obesity

hamilton-Souplet-Zhang's gradient estimates for two weighted nonlinear parabolic equations

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Applied Mathematics(A Journal of Chinese Universities) 2017年第3期32卷 353-364页

作者： MA Bing-qing hUANG Guang-yue Department of Mathematics Henan Normal University Xinxiang 453007 China

In this paper, we consider gradient estimates for positive solutions to the following weighted nonlinear parabolic equations on a complete smooth metric measure space with only Bakry-Émery ricci tensor bounded below: One is $${u_t} = {\Delta _f}u + au\log u + bu$$ with a, b two real constants, and another is $${u_t} = {\Delta _f}u + \lambda {u^\alpha }$$ with λ, α two real constants. We obtain local hamilton-Souplet-Zhang type gradient estimates for the above two nonlinear parabolic equations. In particular, our estimates do not depend on any assumption on f.

关键词： hamilton’s gradient estimate Souplet-Zhang’s gradient estimate weighted nonlinear parabolic equation Bakry-Émery ricci tensor