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Distributional responses to climate change for alpine species of Cyananthus and Primula endemic to the Himalaya-Hengduan Mountains

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Plant Diversity 2019年第1期41卷 26-32页

作者： xie He Kevin S. Burgess Lian-Ming Gao De-Zhu Li Germplasm Bank of Wild Species Kunming Institute of Botany Chinese Academy of Sciences CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences Kunming College of Life Sciences University of Chinese Academy of Sciences Department of Biology College of Letters & Sciences Columbus State University University System of Georgia

Global warming increases the vulnerability of plants, especially alpine herbaceous species, to local extinction. In this study, we collected species distribution information from herbarium specimens for ten selected Cyananthus and Primula alpine species endemic to the Himalaya-Hengduan Mountains(HHM).Combined with climate data from WorldClim, we used Maximum Entropy Modeling(MaxEnt) to project distributional changes from the current time period to 2070. Our predictions indicate that, under a wide range of climate change scenarios, the distributions of all species will shift upward in elevation and northward in latitude; furthermore, under these scenarios, species will expand the size of their range. For the majority of the species in this study, habitats are available to mitigate upward and northward shifts that are projected to be induced by changing climate. If current climate projections, however, increase in magnitude or continue to increase past our projection dates, suitable habitat for future occupation by alpine species will be limited as we predict range contraction or less range expansion for some of the species under more intensified climate scenarios. Our study not only underscores the value of herbarium source information for future climate model projections but also suggests that future studies on the effects of climate change on alpine species should include additional biotic and abiotic factors to provide greater resolution of the local dynamics associated with species persistence under a warming climate.

关键词： Global warming MaxEnt Range expansion Alpine species Himalaya-Hengduan Mountains

An experimental investigation on the mechanism of fluid flow through single rough fracture of rock

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Science China(Technological Sciences) 2013年第8期56卷 2070-2080页

作者： JU Yang ZHANG QinGang YANG YongMing xie HePing GAO Feng WANG HuiJie State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology School of Mechanics and Civil Engineering China University of Mining and Technology Key Laboratory for Energy Engineering Safety and Disaster Mechanics of the Education Ministry Sichuan University

The structure of fractures in nature rock appears irregular and induces complicated seepage flow *** mechanism and quantitative description of fluid flow through rock fractures is a difficult subject that has been greatly concerned in the fields of geotechnical,mining,geological,and petroleum *** order to probe the mechanism of fluid flow and the effects of rough structures,we conducted a few laboratory tests of fluid flow through single rough fractures,in which the Weierstrass-Mandelbrot fractal function and PMMA material were employed to produce the fracture models with various fractal roughnesses.A high-speed video camera was employed to record the fluid flow through the entire single rough fracture with a constant hydraulic *** properties of fluid flow varying with the fracture roughness and the influences of the rough structure were *** components of flow resistance of a single rough fracture were discussed.A fractal model was proposed to relate the fluid resistance to the fracture roughness.A fractal equivalent permeability coefficient of a single rough fracture was *** study aims to provide an experimental basis and reference for better understanding and quantitatively relating the fluid flow properties to the structures of rock fractures.

关键词： seepage flow single fracture rough morphology fractal description rock fractures

Assessment of wetland fragmentation in the middle reaches of the Heihe River by the type change tracker model

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Journal of Arid Land 2015年第2期7卷 177-188页

作者： RuiFeng ZHAO ZuoLun xie LiHua ZHANG Wen ZHU Jie LI Dan LIANG College of Geography and Environment Science Northwest Normal University Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

The quantitative research of wetland landscape fragmentation in the middle reaches of the Heihe River is important for the wetland and oasis sustainable development in the Hexi Corridor. Based on the data of remote sensing and GIS, we constructed the type change tracker model with sliding window technique and spatially mor- phological rule. The suitable scale and optimum scale of the fragmentation model of wetland landscape in the middle reaches of the Heihe River were determined by the area frequency statistics method, Chi-square distribution normal- ized scale variance, fractal dimension and diversity index. By integrating type change tracker model and the optimum scale with GIS spatial analysis, the spatial distribution characteristics of wetland landscape fragmentation in different periods and the related spatial-temporal change process were clarified. The results showed that （1） the type change tracker model, which analyzes the spatial pattern of wetland fragmentation on the pixel level, is better than the tradi- tional wetland fragmentation analysis on the landscape and patch levels; （2） The suitable scale for the wetland frag- mentation ranged from 150 rex150 m to 450 mx450 m and the optimum scale was 250 mx250 m in the middle reaches of the Heihe River; and （3） In the past 35 years, the total wetland area decreased by 23.2% and the frag- mentatJon of wetland markedly increased in the middle reaches of the Heihe River. The areas of core wetlands re- duced by 12.8% and the areas of perforated, edge and patch wetlands increased by 0.8%, 3.1% and 8.9%, respec- tively. The process of wetland fragmentation in the research region showed the order of core wetland, perforated or edge wetland, patch wetland or non-wetland. The results of this study would provide a reference for the protection, utilization and restoration of limited wetland resources and for the sustainable development of the regional eco-environment in the Heihe River Basin.

关键词： wetland landscape pattern fragmentation the type change tracker model Heihe River

Numerical analysis of residence time distribution of solids in a bubbling fluidized bed based on the modified structure-based drag model

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Particuology 2017年第3期15卷 30-38页

作者： Zheng Zou Yunlong Zhao Hu Zhao Hongzhong Li Qingshan Zhu Zhaohui xie Yingbo Li State Key Laboratory of Multi-phase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Belting 100049 China Key Laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences Belting 100190 China

The residence time distribution （RTD） of solids and the fluidized structure of a bubbling fluidized bed were investigated numerically using computational fluid dynamics simulations coupled with the modified structure-based drag model. A general comparison of the simulated results with theoretical values shows reasonable agreement. As the mean residence time is increased, the RTD initial peak intensity decreases and the RTD curve tail extends farther. Numerous small peaks on the RTD curve are induced by the back- mixing and aggregation of particles, which attests to the non-uniform flow structure of the bubbling fluidized bed. The low value of t50 results in poor contact between phases, and the complete exit age of the overflow particles is much longer for back-mixed solids and those caught in dead regions. The formation of a gulf-stream flow and back-mixing for solids induces an even wider spread of RTD.

关键词： FluidizationResidence time distribution Bubbling fiuidized bed Modified structure-based drag mode Computational fluid dynamics CFD

Effect of methyl tert-butyl ether on adipogenesis and glucose metabolism in vitro and in vivo

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Journal of Environmental Sciences 2019年第11期31卷 208-219页

作者： Yue Tang Qidong Ren Qing Wen Caixia Yu Xinni xie Qing Hu Yuguo Du State Key Laboratory of Environmental Chemistry and Eco-toxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China School of Chemical Sciences University of Chinese Academy of Sciences Beijing 100049 China School of Environmental Science and Engineering Southern University of Science and Technology Shenzhen 518055 China

Methyl tert-butyl ether (MTBE),as a widely used gasoline additive,is suspected of being environmentally *** accumulates mainly in adipose tissue,but its effect on obesity or obesity-related metabolic disorders has not been well understood ***,we examined the effect of MTBE on the adipose function and the related metabolic processes with both 3T3-L1 cell line and C57BL/6J mice *** found that exposure to MTBE at the environmental relevant concentration (100 μmol/L) could significantly induce differentiation of preadipocyte and disturb insulin-stimulated glucose uptake of mature *** in vivo observation in male mice showed a positive correlation of visceral white adipose tissue (vWAT) expansion and cell size increase with MTBE treatment in 14 *** tolerance and insulin sensitivity tests demonstrated that MTBE at 1000 μg/(kg·day) disturbed the systemic glucose metabolism in a gender-specific manner,which might be partly attributed to the alterations of gut microbiota community at genus level with respect to Akkermansia,Clostridium XIVb,and *** summary,our study characterized the effect of MTBE on adipose tissue function and glucose homeostasis in vitro and in vivo,and revealed that systemic disorders of the glucose metabolism might be modulated by the related gut microbiota.

关键词： MTBE Adipogenesis Glucose metabolism Metabolic disorder Gut microbiota

Current noises in a topological Josephson junction

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Science China(Physics,Mechanics & Astronomy) 2018年第9期61卷 75-81页

作者： Yu-Hang Li Jie Liu JunTao Song Hua Jiang Qing-Feng Sun XinCheng xie International Center for Quantum Materials School of Physics Peking University Beijing 100871 China Department of Applied Physics School of Science Xi'an Jiaotong University Xi'an 710049 China Department of Physics and Hebei Advanced Thin Film Laboratory Hebei Normal University Shijiazhuang 050024 China College of Physics Optoelectronics and Energy Soochow University Suzhou 215006 China Collaborative Innovation Center of Quantum Matter Beijing 100871 China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences Beijing 100190 China

We study the transport properties of a superconductor-quantum spin Hall insulator-superconductor Josephson junction both in the absence and in the presence of a DC bias voltage. As the system is predicted to host Majorana fermions at its interfaces,the Andreev bond states are supposed to exhibit a distinct 4π periodicity in the superconducting phase difference, namely the fractional Josephson effect. Using the non-equilibrium Green's function method, we calculate the current and the related current noise based on a tight-binding Hamiltonian. Our direct results show that the fractional Josephson effect can not be seen in equilibrium junctions. While in non-equilibrium junctions, this effect can be confirmed by the multiple Andreev reflections induced peaks of the non-equilibrium noise, which appear at discrete frequencies ω = ne V with n being an integer number.

关键词： Majorana fermions Josephson junction current noise non-equilibrium Green's function

Interference alignment scheme for massive MIMO system

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The Journal of China Universities of Posts and Telecommunications 2014年第4期21卷 19-24页

作者： JIANG Jing LV Wei SUN Bo LU Guang-yue xie Yong-bin School of Communication and Information Engineering Xi'an University of Posts & Telecommunications Wireless Technology Pre-research Unit ZTE Cooperation

The performance of massive multiple-input multiple-output （MIMO） system is limited by pilot contamination. To reduce the pilot contamination, uplink and downlink precoding algorithms are put forward based on interference alignment criterion. In the uplink receiving processing, the target function aligns the pilot contamination and the interference signals to the same null space and acquires the maximal space degree of the desired signals. The uplink receiving precoding matrix is solved on maximal signal to interference plus noise ratio （SINR） criterion considering the impact of the pilot contamination on channel estimations. The uplink receiving precoding matrix is used as the downlink transmitting precoding matrix. Exploiting the channel reciprocity, it is proved that, if the uplink receiving precoding matrix achieves maximal S1NR, the identical precoding matrix can be used in the downlink transmission and acquires maximal signal to leakage plus noise ratio （SLNR）. Simulations show that the spectrum efficiency of the proposed algorithm can reach about 1.5 times higher than that of popular matched filtering （MF） precoding algorithm, and about 1.1 times higher than multi-cell minimum mean square error （MMSE） precoding algorithm. The performance of the proposed algorithm can be improved approximately linearly with the increasing of the number of antennas.

关键词： massive MIMO large scale MIMO pilot contamination precoding interference alignment

Synthesis of CeO2 nanosheets with a room temperature ionic liquid assisted method

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Journal of Advanced Ceramics 2016年第2期5卷 111-116页

作者： Ting CHEN Zhixiang xie Weihui JIANG Wan JIANG Xiaojun ZHANG Jianmin LIU School of Material Science and Engineering Jingdezhen Ceramic Institute Jingdezhen 333001 China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Material Science & Engineering Donghua University Shanghai 201620 China

CeO2 nanosheets were directly synthesized by a precipitation process with the aid of 1-butyl-3-methyl-imidazolium ionic liquids at room temperature. The anion species and the concentration of the room temperature ionic liquids (RTILs) have a great influence on the morphology of the resulting products. The as-prepared CeO2 is irregular and agglomerated seriously in the absence of RTILs, while it changes from nanocube to nanosheet with increasing the RTIL concentration or decreasing the polarity and hydrophilicity in the orders [Bmim] Cl > [Bmim] Br > [Bmim] BF4 > [Bmim] PF6. The CeO2 nanocubes have relatively uniform grain size distribution with size of 4.5-6.4 nm, and the nanosheets are assembled by a great deal of nanocrystalline whose length and width extend to hundreds of nanometers. The as-synthesized CeO2 exhibits an excellent removal capacity for the organic pollutant Congo red dye, indicating its potential use in practical wastewater treatment.

关键词： ceria nanocrystalline ionic liquid room temperature catalysis

The relationship between erectile function and complex panurethral stricture： a preliminary ,nvestigative and descriptive study

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Asian Journal of Andrology 2015年第2期17卷 315-318,I0012页

作者： Hong xie Yue-Min Xu Qiang Fu Ying-Long Sa YongQiao Department of Urology Shanghai Jiao Tong University Affiliated Sixth People's Hospital Shanghai China.

The aim of this study was to evaluate erectile function in patients with panurethral stricture after urethral reconstruction. Totally, 65 patients were enrolled. Different urethral reconstructions were performed according to the details of urethral strictures. The erectile function was evaluated before and after surgery. The length and location of stricture and duration from initial diagnosis to operation were recorded. The International Index of Erectile Function-5 （IIEF-5） scores, the quality of life （QoL） scores and the maximal flow rate were obtained before and 3, 6, and 12 months after surgery. A significant improvement in QoL and maximal flow rate was observed 3, 6, and 12 months after surgery compared with those observed before surgery （P 〈 0.05）. An impairment of erectile function was observed in patients with multi-site stricture 3 months after surgery （P 〈 0.05）. Subsequently, these patients recovered 6 and 12 months after surgery. Three months after surgery, the IIEF-5 scores in patients with anterior urethral stricture were higher than those with multi-site stricture. Similar results were observed 6 and 12 months after surgery. No significant difference in age or duration from initial diagnosis to final operation was observed between patients with erectile dysfunction after surgery and patients with normal erectile function. However, a linear regressive relationship was detected between IIEF-5 scores and location of urethral stricture. Surgical reconstruction for treating panurethral strictures has limited effects on erectile function. The location of the stricture, particularly when extended to posterior urethra, was found to be associated with erectile function after surgery.

关键词： erectile dysfunction panurethral stricture urethral reconstruction