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Phylogeography and Cryptic Species Diversity of Paramesotriton caudopunctatus Species Group(Salamandridae: Paramesotriton) in Guizhou, China

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Asian Herpetological Research 2021年第2期12卷 188-200页

作者： Tao LUO Huamei WEN Kai gao Jun ZHOU Jiang ZHOU School of Karst Science Guizhou Normal UniversityGuiyang 550001GuizhouChina School of Life Sciences Central China Normal UniversityWuhan 430000HubeiChina Key Laboratory for Biodiversity ami Ecological Engineering of Ministry of Education College of Life SciencesBeijing Normal UniversityBeijing 100875China

The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary relationships and divergence-time of members of this species group as a whole remain unexplored. In this study, we report the sequencing of one protein coding mitochondrial gene fragment(ND2) and one nuclear gene(POMC), and use a combination of phylogenetic analyses and coalescent simulations to explore the cryptic diversity and evolutionary history of the P. caudopunctatus species group. Phylogenetic relationships revealed that the P. caudopunctatus species group is composed of two major groups, i. e., East Clade and Western-South Clade. The divergence-time and ancestral area estimation suggested that the P. caudopunctatus species group likely originated in the Doupeng Mountains in Guizhou, China at 12.34 Ma(95% HPD: 8.30–14.73), and intraspecific divergence began at about 2.17 Ma(95% HPD: 1.39–2.97). This timing coincides with the orogenesis of the Miaoling Mountains during the Late Miocene to early Pleistocene. The delimitation of species in the P. caudopunctatus species group supports the existence of the currently identified species, and consensus was confirmed across methods for the existence of least to two cryptic species within what has been traditionally considered to be P. caudopunctatus species group. This study is of significance for understanding the species formation, dispersal, and diversity of the tailed amphibians in the karst mountains ecosystem of Guizhou and the role of the Miaoling Mountains as a geographical barrier to species dispersal.

关键词： P.caudopunctatus species group phylogeography cryptic diversity biogeography species delimitation Guizhou

Combined effect of subsurface dam and layered heterogeneity on groundwater flow and salinity distribution in stratified coastal aquifers

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Acta Oceanologica Sinica 2023年第8期42卷 49-60页

作者： Chao gao Jun Kong Jun Wang Tong Zhou Yuncheng Wen Key Laboratory of Coastal Disaster and Protection of Ministry of Education Hohai UniversityNanjing 210000China Nanjing Hydraulic Research Institute Nanjing 210000China

In this paper,for the first time,we investigated the combined effect of subsurface dams and a typical stratified aquifer(two high-permeability layers with a low-permeability layer between them)on groundwater flow and salinity distribution in a tidally influenced coastal unconfined *** dams can inhibit the invasion of saltwater,and the low-permeability layer(LPL)and tide action can increase the effect of subsurface dams and the removal rate of residual *** sensitivity analysis,it was discovered that shifting the dam location towards the inland resulted in a reduction in the effective heights of the *** upper saline plume contracted with increasing dam height,and the upper boundary of LPL was moved to shallower *** the natural removal time increased significantly with increasing dam height and the bottom boundary of LPL was moved to deeper *** addition,if the dam location was close to the sea boundary and the bottom boundary of LPL was moved to deeper regions,we could increase the subsurface dam height to reduce the risks of control of saltwater *** study provides us a comprehensive understanding of the complex hydrodynamics of saltwater intrusion and provides guides for the design of subsurface dams aimed at saltwater intrusion control in stratified coastal aquifers.

关键词： stratified subsurface dams saltwater intrusion residual saltwater natural removal

Double-side role of short chain fatty acids on host health via the gut-organ axes

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Animal Nutrition 2024年第3期18卷 322-339页

作者： Yanan gao Qianqian Yao Lu Meng Jiaqi Wang Nan Zheng Key Laboratory of Quality&Safety Control for Milk and Dairy Products of Ministry of Agriculture and Rural Affairs Institute of Animal SciencesChinese Academy of Agricultural SciencesBeijing 100193China Milk and Milk Products Inspection Center of Ministry of Agriculture and Rural Affairs Institute of Animal SciencesChinese Academy of Agricultural SciencesBeijing 100193China State Key Laboratory of Animal Nutrition Institute of Animal SciencesChinese Academy of Agricultural SciencesBeijing 100193China Department of Food Science Faculty of Veterinary MedicineUniversity of LiègeLiège 4000Belgium

Short chain fatty acids(SCFA)exist in dietary foods and are produced by the fermentation of gut microbiota,and are considered an important element for regulating host *** blood circulation,SCFA produced in the gut and obtained from foods have an impact on the intestinal health as well as vital organs of the *** has been recognized that the gut is the“vital organ”in the *** the gut microbial metabolites,SCFA could create an“axis”connecting the gut and to other ***,the“gut-organ axes”have become a focus of research in recent years to analyze organism *** this review,we summarized the sources,absorption properties,and the function of SCFA in both gut and other peripheral tissues(brain,kidney,liver,lung,bone and cardiovascular)in the way of“gut-organ axes”.Short chain fatty acids exert both beneficial and pathological role in gut and other organs in various ways,in which the beneficial effects are more *** addition,the beneficial effects are reflected in both preventive and therapeutic *** importantly,the mechanisms behinds the gut and other tissues provided insight into the function of SCFA,assisting in the development of novel preventive and therapeutic strategies for maintaining the host health.

关键词： Short chain fatty acid Intestinal barrier Gut-organ axis Host health Beneficial effect Pathological effect

Potential distribution of Haloxylon ammodendron in Central Asia under climate change

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Journal of Arid Land 2024年第9期16卷 1255-1269页

作者： CHEN Zhuo SHAO Minghao HU Zihao gao Xin LEI Jiaqiang Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China National Engineering Technology Research Center for Desert-Oasis Ecological Construction Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Emergency Management Beijing 101601China

Understanding the spatial distribution of plant species and their dynamic changes in arid areas is crucial for addressing the challenges posed by climate *** ammodendron shelterbelts are essential for the protection of plant resources and the control of desertification in Central *** far,the potential suitable habitats of *** in Central Asia are still uncertain in the future under global climate change *** study utilised the maximum entropy(MaxEnt)model to combine the current distribution data of *** with its growth-related data to analyze the potential distribution pattern of *** across Central *** results show that there are suitable habitats of *** in the Aralkum Desert,northern slopes of the Tianshan Mountains,and the upstream of the Tarim River and western edge of the Taklimakan Desert in the Tarim Basin under the current climate *** period from 2021 to 2040 is projected to undergo significant changes in the suitable habitat area of *** in Central Asia,with a projected 15.0% decrease in the unsuitable habitat *** areas farther from the ocean,such as the Caspian Sea and Aralkum Desert,will continue to experience a decrease in the suitable habitats of *** exhibiting frequent fluctuations in the habitat suitability levels are primarily found along the axis stretching from Astana to Kazakhskiy Melkosopochnik in *** regions can transition into suitable habitats under varying climate conditions,requiring the implementation of appropriate human intervention measures to prevent *** climate conditions are expected to cause an eastward shift in the geometric centre of the potential suitable habitats of ***,with the extent of this shift amplifying alongside more greenhouse gas *** study can provide theoretical support for the spatial configuration of *** shelterbelts and desertification co

关键词： Haloxylon ammodendron potential suitable habitats climate change desertification maximum entropy(MaxEnt)model Central Asia Aralkum Desert

WAVELET TRANSFORM THRESHOLD NOISE REDUCTION METHODS IN THE OIL PIPELINE LEAKAGE MONITORING AND POSITIONING SYSTEM

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Journal of Electronics(China) 2010年第3期27卷 405-411页

作者： gao Chao Zhou Shanxue Shenzhen Institute of Information Technology Shenzhen 518029 China Shenzhen Polytechnic Shenzhen 518055 China

This letter investigates the wavelet transform, as well as the principle and the method of the noise reduction based on wavelet transform, it chooses the threshold noise reduction, and discusses in detail the principles, features and design steps of the threshold method. Rigrsure, heursure, sqtwolog and minimization four kinds of threshold selection method are compared qualitatively, and quantitatively. The wavelet analysis toolbox of MATLAB helps to realize the computer simulation of the signal noise reduction. The graphics and calculated standard deviation of the various threshold noise reductions show that, when dealing with the actual pressure signal of the oil pipeline leakage, sqtwolog threshold selection method can effectively remove the noise. Aiming to the pressure signal of the oil pipeline leakage, the best choice is the wavelet threshold noise reduction with sqtwolog threshold. The leakage point is close to the actual position, with the relative error of less than 1%.

关键词： Wavelet transform Decreasing-noise Threshold Oil pipeline leakage MATLAB

Frequency-,radiation pattern-and polarization-reconfigurable antenna for wireless applications

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The Journal of China Universities of Posts and Telecommunications 2023年第1期30卷 87-92页

作者： Bai Xia Su Ming Wang Qingmin Liu Yang gao Zhiwei School of Information Science and Technology Shijiazhuang Tiedao UniversityShijiazhuang 050043China School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

In this communication,a frequency-,radiation pattern-and polarization-reconfigurable antenna employing liquid metal is *** crossed dipole antennas are surrounded by four independent reflectors and directors to realize multi-beam *** length of dipole arms can be adjusted by extracting the liquid metal from the needle tube to achieve frequency *** polarization can be switched by injecting liquid metal into different dipole microfluidic *** is simple in design and has multiple reconfigurable *** antenna with a relative frequency tuning range of 35.8%extending from 2.43 GHz to 3.49 GHz is *** also can perform 6 kinds of beam steering over a 360°coverage and switch between two different *** antenna has potential to employ cognitive radio(CR)and base station in wireless systems.

关键词： reconfigurable antenna liquid metal crossed dipoles reflectors compound reconfiguration

A hierarchical multi-UAV cooperative framework for infrastructure inspection and reconstruction

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Control Theory and Technology 2024年第3期22卷 394-405页

作者： Chuanxiang gao Xinyi Wang Xi Chen Ben M.Chen Department of Mechanical and Automation Engineering The Chinese University of Hong KongHong KongShatinNTChina

Unmanned aerial vehicles(UAVs)are emerging as a powerful tool for inspections and repair works in large-scale and unstructured 3D infrastructures,but current approaches take a long time to cover the entire *** using UAVs for inspections and repair works puts forward a requirement of improving time efficiency in large-scale and cluster *** paper presents a hierarchical multi-UAV cooperative framework for infrastructure inspection and reconstruction to balance the workload and reduce the overall task completion *** proposed framework consists of two stages,the exploration stage and the exploitation stage,resolving the task in a sequential *** the exploration stage,the density map is developed to update global and local information for dynamic load-balanced area partition based on reconstructability and relative positions of UAVs,and the Voronoi-based planner is used to enable the UAVs to reach their best *** obtaining the global map,viewpoints are generated and divided while taking into account the battery capacity of each ***,a shortest path planning method is used to minimize the total traveling cost of these viewpoints for obtaining a high-quality *** experiments are conducted in both a simulated and real environment to show the time efficiency,robustness,and effectiveness of the proposed ***,the whole system is implemented in real applications.

关键词： Multi-UAV Coverage path planning Infrastructure inspection and reconstruction

A nonlinear wake model of a wind turbine considering the yaw wake steering

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Journal of Oceanology and Limnology 2024年第3期42卷 715-727页

作者： Yunzhou LI Zhiteng gao Shoutu LI Suiping QI Xiaoyu TANG College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Multi-function Towing Tank School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Energy and Power Engineering Lanzhou University of TechnologyLanzhou 730050China Institute of Oceanographic Instrumentation Qilu University of Technology(Shandong Academy of Sciences)Qingdao 266061China State Key Laboratory of Industrial Control Technology College of Control Science and EngineeringZhejiang UniversityHangzhou 310027China Laoshan Laboratory Qingdao 266237China

Duo to fluctuations in atmospheric turbulence and yaw control strategies,wind turbines are often in a yaw *** predict the far wake velocity field of wind turbines quickly and accurately,a wake velocity model was derived based on the method of momentum conservation considering the wake steering of the wind turbine under yaw *** consider the shear effect of the vertical incoming wind direction,a two-dimensional Gaussian distribution function was introduced to model the velocity loss at different axial positions in the far wake region based on the assumption of nonlinear wake *** work also developed a“prediction-correction”method to solve the wake velocity field,and the accuracy of the model results was verified in wake experiments on the Garrad Hassan wind ***,a 33-kW two-blade horizontal axis wind turbine was simulated using this method,and the results were compared with the classical wake model under the same parameters and the computational fluid dynamics(CFD)simulation *** results show that the nonlinear wake model well reflected the influence of incoming flow shear and yaw wake steering in the wake velocity ***,computation of the wake flow for the Horns Rev offshore wind farm with 80 wind turbines showed an error within 8%compared to the experimental *** established wake model is less computationally intensive than other methods,has a faster calculation speed,and can be used for engineering calculations of the wake velocity in the far wakefield of wind turbines.

关键词： far wake wake model wake steering wind shear wind farm

Forty Years Development of China's Outward Foreign Direct Investment:Retrospect and the Challe nges Ahead

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China & World Economy 2019年第3期27卷 1-24页

作者： Bijun Wang Kailin gao Institute of World Economics and Politics Chinese Academy of Social Sciences China National School of Development Peking University China

Outwardforeign direct investment(OFDI)has increasingly become an important method for China to integrate into the world *** paper comprehensively reviews and analyzes policy development and the changing pattern of China's OFDI over the past 40 *** divide the development into"restricted”(1978-1999),"relaxed"(2000-2016)and"regulated",(2017 onwards)*** paper also reviews literature on the impact of Chinese OFDI on China and host *** its generally positive effects,large-scale and unbalanced OFDI activities have alarmed Chinese *** developing and developed host countries have expressed their concern over national security and the misbehavior of some Chinese overseas ***,greater supervision and adjustment from quantity to quality growth is necessary for the future development of China's OFDI.

关键词： China foreign exchange reserve going out strategy outward foreign direct investment reform and opening-up policy