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Boundary-Dependent Chaotic regions for a Bose-Einstein Condensate Interacting with Laser Field

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Chinese Physics Letters 2007年第11期24卷 3077-3080页

作者：朱钱泉海文华邓海明 Department of Physics Hunan Normal University Changsha 410081

Spatial chaos of a Bose Einstein condensate perturbed by a weak laser standing wave and a weak laser δ pulse is studied. By using the perturbed chaotic solution we investigate the new type of Melnikov chaotic regions, which depend on an integration constant co determined by the boundary conditions. It is shown that when the │co│ values are small, the chaotic region corresponds to small values of laser wave vector k, and the chaotic region for the larger h values is related to the large │co│ values. The result is confirmed numerically by finding the chaotic and regular orbits on the Poincarg section for the two different parameter regions. Thus, for a fixed co the adjustment of k from a small value to large value can transform the chaotic region into the regular one or on the contrary, which suggests a feasible method for eliminating or generating Melnikov chaos.

关键词： Boundary-Dependent laser field regions

Spatio-temporal distribution and transformation of cropland in geomorphologic regions of China during 1990–2015

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Journal of Geographical Sciences 2019年第2期29卷 180-196页

作者： GAO Xiaoyu CHENG Weiming WANG Nan LIU Qiangyi MA Ting CHEN Yinjun ZHOU Chenghu State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research CAS University of Chinese Academy of Sciences Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Institute of Agricultural Resources and Regional Planning of CAAS

Landforms are an important factor determining the spatial pattern of cropland through allocation of surface water and heat. Therefore, it is of great importance to study the change in cropland distribution from the perspective of geomorphologic divisions. Based on China's multi-year land cover data(1990, 1995, 2000, 2005, 2010 and 2015) and geomorphologic regionalization data, we analyzed the change in cropland area and its distribution pattern in six geomorphologic regions of China over the period of 1990-2015 with the aid of GIS techniques. Our results showed that the total cropland area increased from 177.1 to 178.5 million ha with an average increase rate of 0.03%. Cropland area decreased in southern China and increased in northern China. Region I(Eastern hilly plains) had the highest cropland increase rate, while the cropland dynamic degree of Region IV(Northwestern middle and high mountains, basins and plateaus) was significantly higher than that of other regions. The barycenter of China's cropland shifted from northern China to the northwest over the 25-year period. regions IV and I were the two regions with the greatest increase of cropland. Region II(Southeastern low and middle mountains) and Region V(Southwestern middle and low mountains, plateaus and basins) were the main decreasing cropland regions. The area of cropland remained almost unchanged in Region III(Northern China and Inner Mongolia eastern-central mountains and plateaus) and Region VI(Tibetan Plateau). The loss of cropland occurred mostly in regions I and II as a result of growing industrialization and urbanization, while the increase of cropland occurred mainly in Region IV because of reclamation of grassland and other wasteland. These analyzing results would provide fundamental information for further studies of urban planning, ecosystem management, and natural resourcesconservation in China.

关键词： spatio-temporal distribution transformation of cropland geomorphologic regions China

Characterization and evolutionary dynamics of complex regions in eukaryotic genomes

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Science China(Life Sciences) 2019年第4期62卷 467-488页

作者： José Ranz Bryan Clifton Department of Ecology and Evolutionary Biology University of California Irvine

Complex regions in eukaryotic genomes are typically characterized by duplications of chromosomal stretches that often include one or more genes repeated in a tandem array or in relatively close proximity. Nevertheless, the repetitive nature of these regions,together with the often high sequence identity among repeats, have made complex regions particularly recalcitrant to proper molecular characterization, often being misassembled or completely absent in genome assemblies. This limitation has prevented accurate functional and evolutionary analyses of these regions. This is becoming increasingly relevant as evidence continues to support a central role for complex genomic regions in explaining human disease, developmental innovations, and ecological adaptations across phyla. With the advent of long-read sequencing technologies and suitable assemblers, the development of algorithms that can accommodate sample heterozygosity, and the adoption of a pangenomic-like view of these regions, accurate reconstructions of complex regions are now within reach. These reconstructions will finally allow for accurate functional and evolutionary studies of complex genomic regions, underlying the generation of genotype-phenotype maps of unprecedented resolution.

关键词： complex genomic regions sequencing technologies genome assembly structural variation tandem gene duplicates,evolutionary novelty

Impact of land expropriation on farmers’ livelihoods in the mountainous and hilly regions of Sichuan, China

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Journal of Mountain Science 2019年第11期16卷 2484-2501页

作者： GUO Shi-li LI Chun-jie WEI Ya-li ZHOU Kui LIU Shao-quan XU Ding-de LI Qian-yu China Western Economic Research Center Southwestern University of Finance and EconomicsChengdu 610074China College of Environmental Science and Tourism Nanyang Normal UniversityNanyang 473061China College of Resources Sichuan Agricultural UniversityChengdu 611130China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Sichuan Center for Rural Development Research College of Management of Sichuan Agricultural UniversityChengdu 611130China

Research on the sustainable livelihoods of rural households is of great significance to mitigating rural poverty and reasonable land expropriation policy helps to realize better livelihoods and sustainable *** have conducted considerable research on the relationships between land expropriation and farmers'***,few quantitative studies have used the characteristics of villages as control variables to systematically analyze the impact of land expropriation on farmers'livelihood capital and strategy in the mountainous and hilly regions of *** study uses the Partial Least Squares-Structural Equation Model(PLS-SEM)to systematically explain the impact of land expropriation on farmers'livelihoods in mountainous and hilly regions of Sichuan in 2013,with the characteristics of the village including income,accessibility and terrain as control *** analysis uses both representative sample data of 240 rural households and spatial data calculated using a 30 m Digital Elevation Model(DEM)by Geographic Information System(GIS).Results are as follows:(1)The land expropriation characteristicsare negatively affected by village *** with worse accessibility tend to have fewer land parcels and less land area ***,land that is expropriated from inaccessible villages tends to receive less compensation.(2)Natural capital is negatively affected by number and area of land *** capital is not only directly affected by village accessibility,but also indirectly affected by village accessibility through the mediating effect of the number and area of land parcels expropriated.(3)Physical capital is positively affected by compensation for land expropriation,and negatively affected by village accessibility through compensation for land *** worse a village's accessibility/location is,the less compensation it will receive for land expropriation,resulting in lower physical capital.(4)F

关键词： Sustainable livelihoods Land expropriation Partial least squares-structural equation model Mediating effects Mountainous regions

Role of permafrost in resilience of social-ecological system and its spatio-temporal dynamics in the source regions of Yangtze and Yellow Rivers

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Journal of Mountain Science 2019年第1期16卷 179-194页

作者： FANG Yi-ping ZHU Fu-biao YI Shu-hua QIU Xiao-ping DING Yong-jian Institute of Mountain Hazards and Environment Chinese Academy of Sciences College of Resource and Environment University of Chinese Academy of Sciences School of Economics Hefei University of Technology School of Geographic Sciences Nantong University College of Geography and Resources Science Sichuan Normal University State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences

Permafrost is one of the key components of terrestrial ecosystem in cold regions. In the context of climate change, few studies have investigated resilience of social ecological system(SER) from the perspective of permafrost that restricts the hydrothermal condition of alpine grassland ecosystem. In this paper, based on the structural dynamics, we developed the numerical model for the SER in the permafrost regions of the source of Yangtze and Yellow Rivers, analyzed the spatial-temporal characteristics and sensitivity of the SER, and estimated the effect of permafrost change on the SER. The results indicate that: 1) the SER has an increasing trend, especially after 1997, which is the joint effect of precipitation, temperature, NPP and ecological conservation projects; 2) the SER shows the spatial feature of high in southeast and low in northwest,which is consistent with the variation trends of high southeast and low northwest for the precipitation, temperature and NPP, and low southeast and high northwest for the altitude; 3) the high sensitive regions of SER to the permafrost change have gradually transited from the island distribution to zonal and planar distribution since 1980, moreover, the sensitive degree has gradually reduced; relatively, the sensitivity has high value in the north and south, and low value in the south and east; 4) the thickness of permafrost active layer shows a highly negative correlation with the SER. The contribution rate of permafrost change to the SER is-4.3%, that is, once the thickness of permafrost active layer increases 1 unit, the SER would decrease 0.04 units.

关键词： Resilience of social ecological system Permafrost Permafrost active layer thickness Structural dynamic equation Source regions of Yangtze and Yellow rivers

Complete characterization of strictly positive real regions and robust strictly positive real synthesis method

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Science China(Technological Sciences) 2000年第1期43卷 97-112页

作者：王龙郁文生 Department of Mechanics and Engineering Science Peking University Beijing 100871 China Institute of Automation Chinese Academy of Sciences Beijing 100080 China

The concept of weak strictly positive real regions is introduced, and its properties are discussed . By using the complete discrimination system for polynomials, complete characterization of the (weak) strictly positive real regions for transfer functions in coefficient space is given. A new effective method for robust strictly positive real synthesis is proposed. This method results in necessary and sufficient conditions for low-order stable interval polynomials and segment polynomials, and is also efficient for high-order cases. Numerical examples are provided to illustrate the effectiveness of this method.

关键词： control systems uncertainties strict positive realness robust synthesis weak strictly positive real regions complete discrimination system for polynomials.

Characteristics of Hypertension Death in Low-income regions of Inner Mongolia, China

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Biomedical and Environmental Sciences 2020年第1期33卷 53-57页

作者： YU Di DU Mao Lin SUN De Jun QIAO Su Fang MA Yu Jia Wang Li GAO Yu Min CHEN Yong Sheng MENG Yong Liang SUN Xiao Ling GUO Wen Fang WANG Qing Xia ZHANG Hai Rong LI Wu Yun Ta Na JIA Lei HAO Jing ZHAO Neng Jun SUN Juan Inner Mongolia Medical University Hohhot 010110Inner Mongolia Autonomous RegionChina Inner Mongolia People’s Hospital Hohhot 010017Inner Mongolia Autonomous RegionChina Xincheng District Hospital Hohhot 010010Inner Mongolia Autonomous RegionChina Inner Mongolia Normal University Hohhot 010022Inner Mongolia Autonomous RegionChina Inner Mongolia Autonomous Region Hospital of Traditional Chinese Medicine Hohhot 010020Inner Mongolia Autonomous RegionChina Affiliated People’s Hospital Inner Mongolia Medical UniversityHohhot 010050Inner Mongolia Autonomous RegionChina

Hypertension has been a major risk factor for cardiovascular disease[1].Hypertension overall prevalence in adults is 30%–45%,becoming>60%in people aged above 60 years[2],with a worldwide agestandardised prevalence of... 详细信息

关键词： Characteristics Hypertension Death Low-income regions Inner Mongolia China

Transmission　factors　of　schistosomiasis　japonica　in　the　mountainous　regions　with　type　of　plateau　can

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Chinese Medical Journal 1997年第2期110卷 86-89页

作者：郑江辜学广邱宗林华政辉 lnstituteofParasiticDieeases(IPD)

ＴｒａｎｓｍｉｓｓｉｏｎｆａｃｔｏｒｓｏｆｓｃｈｉｓｔｏｓｏｍｉａｓｉｓｊａｐｏｎｉｃａｉｎｔｈｅｍｏｕｎｔａｉｎｏｕｓｒｅｇｉｏｎｓｗｉｔｈｔｙｐｅｏｆｐｌａｔｅａｕｃａｎｙｏｎａｎｄｐｌａｔｅａｕｂａｓｉｎＺｈｅ... 详细信息

ＴｒａｎｓｍｉｓｓｉｏｎｆａｃｔｏｒｓｏｆｓｃｈｉｓｔｏｓｏｍｉａｓｉｓｊａｐｏｎｉｃａｉｎｔｈｅｍｏｕｎｔａｉｎｏｕｓｒｅｇｉｏｎｓｗｉｔｈｔｙｐｅｏｆｐｌａｔｅａｕｃａｎｙｏｎａｎｄｐｌａｔｅａｕｂａｓｉｎＺｈｅｎｇＪｉａｎｇ郑江，ＧｕＸｕｅｇｕ...

关键词：郑江 factors schistosomiasis the can plateau regions japonica Transmission

Evolutionary relationship of 5′-untranslated regions among Thai dengue-3 viruses,Bangkok isolates,during 24 year-evolution

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Asian Pacific Journal of Tropical Medicine 2015年第3期8卷 176-184页

作者： Watcharee Attatippaholkun Panyupa Pankhong Ananda Nisalak Siripen Kalayanarooj Department of Clinical Chemistry Faculty of Medical TechnologyMahidol University Department of Virology US Army Medical ComponentArmed Forces Research Institute of Medical Sciences Queen Sirikit National Institute of Child Health

Objective:To study evolutionary relationship of the 5'untranslated regions(5'UTRs) in low passage dengue3 viruses(DEN3) isolated from hospitalized children with different clinical manifestations in Bangkok during 24 year-evolution(1977-2000) comparing to the DEN3prototype(H87).Methods:The 5'UTRs of these Thai DEN3 and the H87 prototype were amplified by RT-PCR and *** multiple sequence alignments were done by Codon Code Aligner v 4.0.4 software and their RNA secondary structures were predicted by MFOLD *** of five Thai DEN3 candidates comparing to the 1187 prototype were done in human(HepG2) and the mosquito(C6/36) cell ***:Among these Thai DEN3,the completely identical sequences of their first 89 nucleotides,their high-order secondary structure of 5'UTRs and three SNPs including the predominant C90 T,and two minor SNPs including A109 G and A112 G were *** C90 T of Thai *** isolates was shown predominantly before *** Thai DEN3 candidates with the predominant C90 T were shown to replicate in human(HepG2) and the mosquito(C6/36) cell lines better than the H87 ***,their highly conserved sequences as well as SNPs of the 5'UTR did not appear to correlate with their disease severity in ***:Our findings highlighted evolutionary relationship of the completely identical 89 nucleotide sequence,the high-order secondary structure and the predominant C90 T of the 5'UTR of these Thai DEN3 during 24 year-evolution further suggesting to be their genetic markers and magic targets for future research on antiviral therapy as well as vaccine approaches of Thai DEN3.

关键词： Thai dengue-3 viruses Evolutionary relationship 5’untranslated regions 24 Year-evolution