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slands conserve high species richness and areas of endemism of Hormaphidinae aphids

Current Zoology 2017年第6期63卷 623-632页

作者： Yang LI Jing CHEN Liyun jiang Gexia QIAO Key Laboratory of Zoological Systematics and Evolution Institute of Zoology Chinese Academy of Sciences Beijing 100101 China College of Life Sciences University of Chinese Academy of Sciences Beijing 100049 China

Patterns of biodiversity and endemism are important and form the foundation for biogeography and conservation studies. Hormaphidinae is an aphid group mainly distributed in the Sino-Japanese, Oriental, and Nearctic zoogeographic realms. To infer the areas of endemism of Hormaphidinae aphids in the Sino-Japanese and Oriental realms, we employed a geographical distribution dataset covering all 225 species in subfamily Hormaphidinae. In total, 1,245 distribution occurrence records for all species were analyzed in addition to the number of species in a certain grid cell to calculate species richness. Two methods （parsimony analysis of endemicity （PAE） and the use of an optimization criterion-- NDMNNDM） using a total of 6 grid sizes were applied to detect possible areas of endemism and to assess the probable effects of the 2 different methods and 6 grid sizes on the results of the patterns of the areas of endemism. The results revealed that islands presented most of the areas with high species richness and endemic species, particularly Japan, Taiwan Island, Java Island, the Malaysian Peninsula, southeast Himalaya, and the Hengduan Mountains. Most of these areas of endemism were located on islands or a peninsula. Islands were therefore shown to play an essential role in facilitating the formation of high species richness and endemism. Different grid sizes directly determined the regions of the areas of endemism, with small grid sizes tending to detect small and discrete areas of endemism and large grid sizes identifying continuous areas of endemism. In terms of the two methods, NDM/VNDM was found to identify more areas of endemism than PAE.

关键词： biogeography endemism area Hormaphidinae island biogeegraphy species richness.

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Sphalerite Rb-Sr Dating and in situ Sulfur Isotope Analysis of the Daliangzi Lead-Zinc Deposit in Sichuan Province, SW China

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Journal of Earth Science 2018年第3期29卷 573-586页

作者： Wenhao Liu Xiaojun Zhang Jun Zhang Manrong jiang Faculty of Earth Resources China University of Geosciences Institute of Geological Survey China University of Geosciences

This study reports the sphalerite Rb-Sr age and LA-MC-ICP-MS in situ sulfur isotope analysis results of the Daliangzi Lead-Zinc Deposit in the Sichuan-Yunnan-Guizhou （SYG） triangle. Sphalerite Rb-Sr dating yields a Mississippian age of 345.2±3.6 Ma （MSWD=I.4）, which is older than the published Late Triassic mineralization ages （230-200 Ma） of some other deposits. This indicates that at least two stages of lead-zinc mineralization have occurred in the SYG lead-zinc triangle. The first stage occurred in the Mississippian under an extensional environment, while the second stage occurred in the Late Triassic under a compressional environment. In situ sulfur isotope analysis of sphalerite growth zoning presents relatively large δ^34S values of 11.3‰-15.2‰ with small variations. The large δ^34S values indicate a reduced sulfur source of thermochemical reduction of seawater sulfates. Abundant organic matter in the black fracture zone possibly supplied reductants for thermochemical sulfate reduction （TSR） at the mineralization site. The small variation of δ^34S values suggests a slow and stable TSR process that could prevent the sudden supersaturation of sphalerite in the fluid and the resulting of fast participation. This is consistent with the well-crystallized characteristic of the sphalerite of the Daliangzi Deposit.

关键词： sphalerite Rb-Sr in situ sulfur isotope thermochemical reduction Daliangzi Mississippi Valley-type.

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Calculation of Ecological Footprint Based on Modified Method and Quantitative Analysis of Its Impact Factors——A Case Study of Shanghai

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Chinese Geographical Science 2006年第4期16卷 306-313页

作者： GAO Chengkang jiang Dahe WANG Dan YAN Jonathan College of Environmental Science and Engineering Tongji University Shanghai 200092 China Department of Geography Shanghai Normal University Shanghai 200234 China Department of Pacific and International Affairs University of California San Diego USA

Ecological footprint （EF） has attracted much attention internationally as a potential indicator for sustainable development. In China, EF has also gained recognition in related fields and disciplines. Moreover, some scholars in these fields have proposed alternative methods to calculate EF and have made some progress. This paper, therefore, begins with the introduction and development of EF in China. However, the established methods of EF calculation hold some limitations, such as indicator variance and result abnormality. In order to resolve those problems, the authors make a further modification considering the demand of EF as a comprehensive indicator： 1） More accurate analysis has been done to divide EF into several parts： imported EF, exported EF, and producible EF, which is the solution to the problem of abnormality in original EF results and can explain abnormal phenomena reasonably. 2） Considering the actual situa- tion of Shanghai, emended equivalence factor is brought forward and a matrix is formed with equivalence factors. The measure can reduce the deviation between the fact and the results. 3） The calculation compares local yield with global average yield to analyze the effects of yields. And based on local yields in different years, the results are more accurate. Finally, the calculation method is applied to calculating EF of Shanghai from 1980 to 2003, and the subsequent detailed analysis is presented. Available data and results suggest a statistically significant correlation coefficient between EF and GDP, population density and urbaniTation level. Through analyzing the process of calculating EF and its results, it can be seen that EF, as a macro-indicator, can not exactly indicate whether development within a region can meet the re- quests of sustainable development, which can be explained by the fact that the result of EF is impacted greatly by sub- jective factors including national policy,available technology, population, etc. Nevertheless, EF ca

关键词： ecological footprint quantitative analysis impact factors Shanghai

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Quantitatively distinguishing sediments from the Yangtze River and the Yellow River using δEu_N-ΣREEs plot

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Science China Earth Sciences 2009年第2期52卷 232-241页

作者： jiang FuQing ZHOU XiaoJing LI AnChun LI TieGang Key laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China Graduate University Chinese Academy of SciencesBeijing 100049China

Sediment samples were collected from the lower channel of the Yangtze River and the Yellow River and the contents of rare earth elements (REEs) were measured. In addition, some historical REEs data were collected from published literatures. Based on the δEuN-ΣREEs plot, a clear boundary was found be-tween the sediments from the two rivers. The boundary can be described as an orthogonal polynomial equation by ordinary linear regression with sediments from the Yangtze River located above the curve and sediments from the Yellow River located below the curve. To validate this method, the REEs con-tents of sediments collected from the estuaries of the Yangtze River and the Yellow River were meas-ured. In addition, the REEs data of sediment Core 255 from the Yangtze River and Core YA01 from the Yellow River were collected. Results show that the samples from the Yangtze River estuary and Core 255 almost are above the curve and most samples from the Yellow River estuary and Core YA01 are below the curve in the δEuN-ΣREEs plot. The plot and the regression equation can be used to distin-guish sediments from the Yangtze River and the Yellow River intuitively and quantitatively, and to trace the sediment provenance of the eastern seas of China. The difference between the sediments from two rivers in the δEuN-ΣREEs plot is caused by different mineral compositions and regional climate patterns of the source areas. The relationship between δEuN and ΣREEs is changed little during the transport from the source area to the river, and from river to the sea. Thus the original information on mineral compositions and climate of the source area was preserved.

关键词： sediment provenance Yangtze River Yellow River δEuN-ΣREEs plot

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Microbial genes for degrading plant-derived carbon are a key factor affecting soil respiration and temperature sensitivity in plateau peatlands

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Pedosphere 2024年第6期34卷 1026-1037页

作者： Wei jiang Mingyao XIONG Shuzhen ZOU Di KANG Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education) China West Normal University Key Laboratory of Environmental Science and Biodiversity Conservation (Sichuan Province) China West Normal University

Peatlands on the southwestern plateau of China are important carbon sinks for high-altitude terrestrial ecosystems in ***,the specific microecological mechanism responsible for alterations in carbon processes in this region due to the simultaneous impacts of global warming and drought has not been fully *** this mechanism will improve our understanding of carbon cycle feedback in peatland ecosystems,as it is affected by changes in hydrology and temperature,especially in vulnerable *** study examined the influence of soil carbon decomposition functional microorganisms on soil respiration and temperature sensitivity (expressed as Q10) in high-elevation peatlands using field investigations,simulated warming experiments,and metagenomic *** found that hydrothermal conditions had a significant effect on soil respiration,leading to an increase in cumulative soil respiration as soil moisture and temperature *** moisture affected soil respiration and soil organic carbon mainly through soil microorganisms,with a predominance of carbon-decomposing *** found that genes regulating the decomposition of plant-derived carbon such as cellulose and lignin were the critical factor influencing Q10in *** involved in cellulose and lignin decomposition showed a significant positive correlation with Q10（P<0.05）,while genes involved in hemicellulose decomposition showed a significant negative correlation with Q10（P<0.05）.Specifically,genes such as ACO,xylF,and hpaE,which are involved in lignin decomposition,and glgB,which is responsible for cellulose decomposition,showed significant positive correlations （P<0.05） with ***,the gene uxaC,involved in the decomposition of hemicellulose,showed a significant negative correlation （P<0.05） with ***,we analyzed the relevant carbon metabolic pathways and found that although they were affected by water,they were not significantly related to *** short,th

关键词： carbon cycle carbon decomposition drought global warming lignin metagenomic sequencing microbial functional gene

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Microstructure-based hot extrusion process control principles for nickel-base superalloy pipes

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Progress in Natural Science:Materials International 2018年第3期28卷 391-398页

作者： He jiang Linhan Li Jianxin Dong Xishan Xie School of Materials Science and Engineering University of Science and Technology Beijing

The properties of nickel-base superalloy pipes are determined by microstructure, and the microstructure can be tuned by hot extrusion process. There are two major questions in hot extrusion: one is how to successfully extrude pipes without apparent defects, the other is how to make the microstructure under control. However, up to now, there is no systematical report about hot extrusion process and microstructure control for nickel-base superalloys. In present study, a series of technical control principles for hot extrusion are proposed basing on practical manufacture facts, large amounts of experimental studies and finite element simulation of several typical nickel-base superalloys. The common used technical control principles can be applied for hot extrusion parameters determination to maintain safety hot extrusion and microstructure control. In the investigation of microstructure control based hot extrusion principles, the action rules of different working parameters on hot extrusion field quantities were established. The upper and lower limits of different principles were obtained in consideration of materials characteristics and extruder conditions. The limitations were overlapped on the action rules to determine the optimized hot extrusion parameters. The microstructure-based control principle proposed in present work can provide theoretical guidance for hot extrusion parameter determination and optimization.

关键词： Nickel-base superalloy Hot extrusion Microstructure evolution Control principle

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lk,s-Singular values and spectral radius of partially symmetric rectangular tensors

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Frontiers of Mathematics in China 2016年第3期11卷 605-622页

作者： Hongmei YAO Bingsong LONG Changjiang BU jiang ZHOU College of Science Harbin Engineering University Harbin 150001 China

The real rectangular tensors arise from the strong ellipticity condition problem in solid mechanics and the entanglement problem in quantum physics. In this paper, we first study properties oflk,singular values of real rectangular tensors. Then, a necessary and sufficient condition for the positive definiteness of partially symmetric rectangular tensors is given. Furthermore, we show that the weak Perron-Frobenius theorem for nonnegative partially symmetric rectangular tensor keeps valid under some new conditions and we prove a maximum property for the largest lk,S-singular values of nonnegative partially symmetric rectangular tensor. Finally, we prove that the largest lk,s- singular value of nonnegative weakly irreducible partially symmetric rectangular tensor is still geometrically simple.

关键词： lk,s-Singular values spectral radius positive definiteness partiallysymmetric rectangular tensor weakly irreducible

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Possible Streams of the Globular Clusters in the Galaxy

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Chinese Journal of Astronomy and Astrophysics 2007年第1期7卷 111-119页

作者： Shuang Gao Bi-Wei jiang Yong-Heng Zhao Department of Astronomy Beijing Normal University Beijing 100875 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

We aim to retrieve ghost streams under the assumption that all the globular clusters in our Galaxy were formed in very early merge events. Our results are based on two speculations： that the specific energy and angular momentum of the globular clusters after merge are not changed in the course of evolution and that the globular clusters with a common origin would stay in the same orbit plane as the parent galaxy. After taking into account the apogalacticum distance of the orbits, we suggest with some Confidence five possible streams. The number of streams is consistent with the previous results. Three of the four well established members of the Sagittadus stream were found to be in one of our streams. Several other globular clusters in our result were also thought to come from accretion by previous researchers. The orbital parameters of the streams are derived, which provide a way to test whether these streams are true with the help of more accurate measurement of proper motions of the globular clusters.

关键词： globular clusters general-Galaxy formation-Galaxy halo

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Cdk phosphorylation licenses Kif4A chromosome localization required for early mitotic progression

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Journal of Molecular Cell Biology 2018年第4期10卷 358-370页

作者： Zhixiong Dong Changjun Zhu Qimin Zhan Wei jiang State Key Laboratory of Molecular Oncology National Cancer Center/Cancer Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100021 China Key Laboratory of Molecular and Cellular Systems Biology Tianjin Normal University Tianjin 300387 China Tianjin Key Laboratory of Animal and Plant Resistance College of Life Sciences Tianjin Normal University Tianjin 300387 China

The chromokinesin Kif4A controls proper chromosome condensation, congression/alignment, and cytokinesis to ensure faithful genetic inheritance. Here, we report that Cdk phosphorylation of human Kif4A at T1161 licenses Kif4A chromosomal localization, which, in turn, controls Kif4A early mitotic function. Phosphorylated Kif4A （Kif4A^WT） or Cdk phospho-mimetic Kif4A mutant （Kif4A^TE） associated with chromosomes and condensin I （non-SMC subunit CAP-G and core subunit SMC2） to regulate chromosome condensation, spindle morphology, and chromosome congression/alignment in early mitosis. In contrast, Cdk non-phosphorylatable Kif4A mutant （Kif4A^TA） could neither localize on chromosomes nor associate with CAP-G and SMC2. Furthermore, Kif4A^TA could not rescue defective chromosome condensation, spindle morphology, or chromosome congression/alignment in cells depleted of endogenous Kif4A, which activated a mitotic checkpoint and delayed early mitotic progression. However, targeting Kif4A^TA to chromosomes by fusion of Kif4A^TA with Histone H1 resulted in restoration of chromosome and spindle functions of Kif4A, similar to Kif4A^WT and Kif4A^TE, in cells depleted of endogenous Kif4A. Thus, our results demonstrate that Cdk phosphorylation-licensed chromosomal localization of Kif4A plays a critical role in regulating early mitotic functions of Kif4A that are important for early mitotic progression.

关键词： Kif4A chromokinesin Cdk phosphorylation mitosis

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Possible Contribution of Mature γ-ray Pulsars to Cosmic-ray Positrons

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Chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 87-95页

作者： Quan-Gui Gao Ze-Jun jiang Li Zhang National Astronomical Observatories / Yunnan Observatories Chinese Academy of Sciences Kunming 650011 Department of Physics Yunnan University Kunming 650091

We restudy the possible contribution of mature gamma-ray pulsars to cosmic ray positrons based on the new version of outer gap model. In this model, the inclination angle and average properties of the outer gap are taken into account, and more mature pulsars can have the outer gap and emit high energy photons. Half of the primary particles in the outer gaps will flow back toward the star surface and emit synchrotron photons, which can produce electron/positron pairs by the cascade of pair production. Some of these pairs will escape from the light cylinder and be accelerated to relativistic energies in the pulsar wind driven by low-frequency electromagnetic waves. Using a Monte Carlo method, we obtain a sample of mature gamma-ray pulsars and then calculate the production of the positrons from these pulsars. The observed excess of cosmic positrons can be well explained by this model.

关键词： stars pulsars general - acceleration of particles - ISM cosmic rays

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