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Spatial and temporal variation of drought index in a typical steep alpine terrain in Hengduan Mountains

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Journal of Mountain Science 2016年第7期13卷 1186-1199页

作者： ZHU Guo-feng YANG ling qin Da-he TONG Hua-li LIU Yuan-feng LI Jia-fang College of Geography and Environment Science Northwest Normal University State Key Laboratory of Cryosphere Sciences Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

This study describes the spatial and temporal variation of a drought index and makes inferences regarding the environmental factors that influence this variability in the Hengduan Mountains. A drought index is typically used to determine the moisture conditions and the magnitude of water deficiency in a given area. Based on data from 26 meteorological stations over the period 1960-2012, the spatial and temporal variations of the drought index were analyzed using a thin plate smoothing splines method that considered elevation as a covariate. The drought index was estimated based on the potential evapotranspiration(E0) as defined by the Penman Monteith model modified by FAO(1998). The results of the reported analysis showed that the drought index in the Hengduan Mountains has been decreasing since 1960 at a rate of-0.008/a. This represented a progressive shift from the "sub-humid" class, which typified the wider area in the Hengduan Mountains, toward the "humid" class, which appeared in the Hengduan Mountains areas. The drought index was relatively high in the north and low in the south and the variation of the drought index varied with seasons. The drought index showed increasing trends in summer and autumn and it is greater in autumn than in summer, while it showed a decreasing trend in spring and winter. Drought index is inversely proportional to the soil relative humidity and Normalized Difference Vegetation Index(NDVI).

关键词： Drought index Normalized Difference Vegetation Index Evapotranspiration Thin plate smoothing splines Hengduan Mountains

Serum chitinase-3-like protein 1 is a biomarker of liver fibrosis in patients with chronic hepatitis B in China

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Hepatobiliary & Pancreatic Diseases International 2020年第4期19卷 384-389页

作者： Xin Jin Bin Fu Zheng-Jie Wu Xiao-qin Zheng Jian-Hua Hu Lin-feng Jin ling-ling Tang State Key Laboratory for Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China College of Medicine Shaoxing UniversityShaoxing 312000China Shulan(Hangzhou)Hospital Affiliated to Zhejiang Shuren University Shulan International Medical CollegeHangzhou 310022China

Background:Serum chitinase-3-like protein 1(CHI3L1)is a potential biomarker for fibrosis *** aimed to evaluate serum CHI3L1 as a noninvasive diagnostic marker for chronic hepatitis B virusrelated ***:Serum CHI3L1 levels were measured by ELISA in 134 chronic hepatitis B(CHB)*** fibrosis was defined as a liver stiffness>9.7 *** performance of CHI3L1 was assessed and compared to that of other noninvasive tests by receiver operating characteristic(ROC)***:Serum CHI3L1 levels were significantly higher in CHB patients with significant hepatic fibrosis(≥F2)than in those without significant hepatic fibrosis(

关键词： Chitinase-3-like protein 1 Hepatitis B virus Noninvasive Liver stiffness Significant fibrosis

A mass-conserved multiphase lattice Boltzmann method based on high-order difference

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Chinese Physics B 2020年第3期29卷 292-302页

作者： Zhang-Rong qin Yan-Yan Chen feng-Ru ling ling-Juan Meng Chao-Ying Zhang Guangxi Collaborative Innovation Center of Multi-source Information Integration and Intelligent Processing Guangxi Normal UniversityGuilin 541004China

The Z–S–C multiphase lattice Boltzmann model [Zheng, Shu, and Chew(ZSC), J. Comput. Phys. 218, 353(2006)]is favored due to its good stability, high efficiency, and large density ratio. However, in terms of mass conservation, this model is not satisfactory during the simulation computations. In this paper, a mass correction is introduced into the ZSC model to make up the mass leakage, while a high-order difference is used to calculate the gradient of the order parameter to improve the accuracy. To verify the improved model, several three-dimensional multiphase flow simulations are carried out,including a bubble in a stationary flow, the merging of two bubbles, and the bubble rising under buoyancy. The numerical simulations show that the results from the present model are in good agreement with those from previous experiments and simulations. The present model not only retains the good properties of the original ZSC model, but also achieves the mass conservation and higher accuracy.

关键词： lattice Boltzmann method high-order difference mass conservation large density ratio

The battle of crops against drought:Genetic dissection and improvement

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Journal of Integrative Plant Biology 2023年第2期65卷 496-525页

作者： Zhirui Yang feng qin State Key Laboratory of Plant Environmental Resilience College of Biological SciencesChina Agricultural UniversityBeijing 100193China

With ongoing global climate change,water scarcity-induced drought stress remains a major threat to agricultural *** undergo a series of physiological and morphological changes to cope with drought stress,including stomatal closure to reduce transpiration and changes in root architecture to optimize water *** phenotypic and multi-omics studies have recently identified a number of drought-related genetic resources in different crop *** functional dissection of these genes using molecular techniques has enriched our understanding of drought responses in crops and has provided genetic targets for enhancing resistance to ***,we review recent advances in the cloning and functional analysis of drought resistance genes and the development of technologies to mitigate the threat of drought to crop production.

关键词： crops drought resistance gene cloning genetic improvement

The MADS-box transcription factor CmAGL11 modulates somatic embryogenesis in Chinese chestnut(Castanea mollissima Blume)

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Journal of Integrative Agriculture 2020年第4期19卷 1033-1043页

作者： GAO Yue-rong SUN Jia-chen SUN Zhi-lin XING Yu ZHANG qing FANG Ke-feng CAO qing-qin qin ling Beijing Advanced Innovation Center for Tree Breeding by Molecular Design Beijing University of AgricultureBeijing 102206P.R.China Beijing Bei Nong Enterprise Management Co. Ltd.Beijing 102206P.R.China College of Plant Science and Technology Beijing Key Laboratory for Agricultural Application and New TechniqueBeijing University of AgricultureBeijing 102206P.R.China Beijing Collaborative Innovation Center for Eco-environmental Improvement with Forestry and Fruit Trees Beijing University of AgricultureBeijing 102206P.R.China

Somatic embryogenesis(SE)is an effective approach of in vitro regeneration that depends on plant cell ***,largely unknown of molecular mechanisms of SE in woody plants such as Chinese chestnut(Castanea mollissima Blume),limits the development of the woody plant ***,we report the MADS-box transcription factor Cm AGL11 in Chinese *** AGL11 transcripts specifically accumulated in the globular *** of Cm AGL11 in chestnut callus enhanced its SE capacity,and the development of somatic embryos occurred significantly faster than in the ***-seq results showed that Cm AGL11 affects the expression of several genes related to the gibberellin,auxin,and ethylene ***,the analysis of DNA methylation status indicated that the promoter methylation plays a role in regulation of Cm AGL11 expression during *** results demonstrated that Cm AGL11 plays an important role in the SE process in Chinese chestnut,possibly by regulating gibberellin,auxin,and ethylene *** will help establish an efficient platform to accelerate genetic improvement and germplasm innovation in Chinese chestnut.

关键词： Chinese chestnut CmAGL11 somatic embryogenesis DNA methylation

Understanding the pathogenic evolution of Zika virus

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Science China(Life Sciences) 2016年第7期59卷 737-739页

作者： Xiao-feng qin Center of Systems Medicine Institute of Basic Medical Sciences Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100005 China Suzhou Institute of Systems Medicine Suzhou 215123 China

Unlike the previous circulating strains that were not associ- ated with significant human pathology, recent circulating Zika virus （ZIKV） strains isolated during the 2015-2016 Brazilian Outbreak are highly suspected to cause neuropa- thology, including disorders of fetal brain development and Guillain-Barr6 syndrome （Broutet et al., 2016）. Studies have revealed that recent ZIKV strains can be spread through maternal-fetal （Calvet et al., 2016） and sexual （Hills et al., 2016） transmission, in addition to the traditional route of infection via mosquitoes.

关键词：病毒演变病原大脑发育病理学流行株综合征菌株

Biome reconstruction on the Tibetan Plateau since the Last Glacial Maximum using a machine learning method

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Science China Earth Sciences 2022年第3期65卷 518-535页

作者： feng qin Yan ZHAO Xianyong CAO Key Laboratory ofLand Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Alpine Paleoecology and Human Adaptation(ALPHA)Group State Key Laboratory of Tibetan Plateau Earth System Science(LATPES)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Historical biome changes on the Tibetan Plateau provide important information that improves our understanding of the alpine vegetation responses to climate ***,a comprehensively quantitative reconstruction of the historical Tibetan Plateau biomes is not possible due to the lack of quantitative methods that enable appropriate classification of alpine biomes based on proxy data such as fossil pollen *** this study,a pollen-based biome classification model was developed by applying a random forest algorithm(a supervised machine learning method)based on modern pollen assemblages on and around the Tibetan Plateau,and its robustness was assessed by comparing its results with the predictions of the biomisation *** results indicated that modern biome distributions reconstructed using the random forest model based on modern pollen data generally concurred with the observed zonal *** random forest model had a significantly higher accuracy than the biomisation method,indicating the former is a more suitable tool for reconstructing alpine biome changes on the Tibetan *** random forest model was then applied to reconstruct the Tibetan Plateau biome changes from 22 ka BP to the present based on 51 fossil pollen *** reconstructed biome distribution changes on the Tibetan Plateau generally corresponded to global climate changes and Asian monsoon *** the Last Glacial Maximum,the Tibetan Plateau was mainly desert with subtropical forests distributed in the *** the last deglaciation,the alpine steppe began expanding and gradually became zonal vegetation in the central and eastern *** meadow occupied the eastern and southeastern areas of the Tibetan Plateau since the early Holocene,and the forest-meadow-steppe-desert pattern running southeast to northwest on the Tibetan Plateau was established *** the mid-Holocene,subtropical forests extended north,which reflected the“optimum”***

关键词： Biome reconstruction Random forest algorithm Biomisation method Pollen data Last Glacial Maximum Tibetan Plateau

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Precipitation Distribution of the Extended Global Spring-Autumn Monsoon and Its Possible Formation Mechanism

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Journal of Ocean University of China 2021年第5期20卷 1027-1036页

作者： qin ling HUANG Fei XU Shibin Key Laboratory of Physical Oceanography Ocean University of ChinaQingdao 266100China Laboratory for Ocean and Climate Dynamics Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266100China Ningbo Collaborative Innovation Center of Nonlinear Hazard System of Ocean and Atmosphere Ningbo UniversityNingbo 315211China

The global monsoon(GM)comprises two major modes,namely,the solstitial mode and equinoctial asymmetric *** this paper,we extend the GM domain from the tropics to the global region and name it the global spring-autumn monsoon(GSAM),which mainly indicates a spring-autumn asymmetrical precipitation pattern exhibiting annual *** distribution and possible formation mechanisms are also *** GSAM domain is mainly distributed over oceans,located both in the midlatitude and tropical regions of the Pacific and *** the GSAM domains of both the Northern and Southern Hemispheres,more precipitation occurs in local autumn than in local *** formation mechanisms of GSAM precipitation vary according to the different *** precipitation in the tropical domain of the Eastern Hemisphere is influenced by the circulation differences between the onset and retreat periods of the Asian summer monsoon,while tropical cyclone activities cause precipitation over the South China Sea(SCS)and western North Pacific(WNP).GSAM precipitation in the tropical domain of the Western Hemisphere is influenced by the tropical asymmetrical circulation between the Northern and Southern Hemispheres and the variation in the intertropical convergence zone(ITCZ)driven by the intensity of the sea surface temperature cold tongues over the equatorial eastern Pacific and eastern *** precipitation in the midlatitude domain is influenced by the differences in water vapor transportation and convergence between spring and *** addition,GSAM precipitation is also affected by extratropical cyclone activities.

关键词： global monsoon equinoctial asymmetric mode monsoon precipitation mechanism

Carbon-based materials with combined functions of thermal management and electromagnetic protection: Preparation, mechanisms, properties, and applications

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Nano Research 2024年第3期17卷 883-903页

作者： Junwei Yue Yiyu feng Mengmeng qin Wei feng School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin 300350China

The proliferation of high-power,highly informationized,and highly integrated electronic devices and weapons equipment has given rise to increasingly conspicuous issues about electromagnetic(EM)pollution and thermal *** issues,in turn,impose constraints on the performance of such equipment and jeopardize personnel *** materials,owing to their diverse and modifiable structures,offer adjustable thermal and electric conductivity,rendering them highly promising for applications in fields such as thermal management and EM protection which have garnered extensive research and *** pursuit of integrated device and equipment development has elevated the demand for multifunctional materials,prompting significant research into carbon-based composite materials that include both thermal management and EM protection ***,there are no relevant reviews on this topic at ***,this work consolidates research findings from recent years on carbon matrix composites exhibiting dual attributes of thermal management and EM *** attributes include thermally conductive electromagnetic interference(EMI)shielding materials,thermally insulating EMI shielding materials,thermally conductive EM wave(EMW)absorbing materials,and thermally insulating EMW absorbing *** paper elucidates the fundamental principles underpinning thermal conduction,thermal insulation,EMW absorbing,and EMI ***,it engages in discussions surrounding areas of contention,design strategies,and the functional properties of various material ***,the paper concludes by presenting the challenges encountered and potential research strategies about composites endowed with both thermal management and EM protection functionalities,while also envisaging the development of novel multifunctional EM protection materials.

关键词： carbon-based composites electromagnetic interference shielding microwave absorption thermal conduction thermal insulation