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Assessment of Future Drought in Southwest China Based on CMIP5 Multimodel Projections

Advances in Atmospheric Sciences 2014年第5期31卷 1035-1050页

作者： WANG lin CHEN wen ZHOU wen Center for Monsoon System Research Institute of Atmospheric Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Guy Carpenter Asia-Pacific Climate Impact Centre School of Energy and EnvironmentCity University of Hong Kong

In the last decade, a series of severe and extensive droughts have swept across Southwest China, resulting in tremendous economic losses, deaths, and disruption to society. Consequently, this study is motivated by the paramount importance of as- sessing future changes in drought in Southwest China. Precipitation is likely to decrease over most parts of Southwest China around the beginning of the century, followed by widespread precipitation increases; the increase in potential evapotran- spiration （PET）, due to the joint effects of increased temperature and surface net radiation and decreased relative humidity, will overwhelm the whole region throughout the entire 21st century. In comparative terms, the enhancement of PET will outweigh that of precipitation, particularly under Representative Concentration Pathway （RCP） 8.5, resulting in intensified drought. Generally, the drying tendency will be in the southeast portion, whereas the mountainous region in the northwest will become increasingly wetter owing to abundant precipitation increases. Droughts classified as moderate/severe according to historical standards will become the norm in the 2080s under RCP4.5/RCP8.5. Future drought changes will manifest different characteristics depending on the time scale： the magnitude of change at a time scale of 48 months is nearly twice as great as that at 3 months. Furthermore, we will see that not only will incidences of severe and extreme drought increase dramatically in the future, but extremely wet events will also become more probable.

关键词： drought Standardized Precipitation Evapotranspiration Index spatial disaggregation Southwest China

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Atomically Dispersed Dual‑Metal Sites Showing Unique Reactivity and Dynamism for Electrocatalysis

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Nano-Micro Letters 2023年第8期15卷 192-204页

作者： Jun‑xi Wu wen‑xing Chen Chun‑Ting He Kai Zheng lin‑ling Zhuo Zhen‑Hua Zhao Jie‑Peng Zhang MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of ChemistrySun Yat-Sen UniversityGuangzhou 510275People’s Republic of China Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang 330022People’s Republic of China Energy&Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081People’s Republic of China

The real structure and in situ evolution of catalysts under working conditions are of paramount importance,especially for bifunctional ***,we report asymmetric structural evolution and dynamic hydrogen-bonding promotion mechanism of an atomically dispersed *** of Co/Ni-doped MAF-4/ZIF-8 yielded nitrogen-doped porous carbons functionalized by atomically dispersed Co–Ni dual-metal sites with an unprecedented N8V4 structure,which can serve as an efficient bifunctional electrocatalyst for overall water *** importantly,the electrocatalyst showed remarkable activation behavior due to the in situ oxidation of the carbon substrate to form C–OH *** functional theory calculations suggested that the flexible C–OH groups can form reversible hydrogen bonds with the oxygen evolution reaction intermediates,giving a bridge between elementary reactions to break the conventional scaling relationship.

关键词： Metal-organic frameworks Atomically dispersed catalyst Hydrogen bond Overall water splitting

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Two-phase SPH simulation of vertical water entry of a two-dimensional structure

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Journal of Hydrodynamics 2018年第5期30卷 841-850页

作者： lin Ma xi Zhao Hua Liu Key Laboratory of Hydrodynamics（Ministry of Education） School of Naval ArchitectureOcean and civil EngineeringShanghai Jiao Tong UniversityShanghai200240 China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China College of Ocean Science and Engineering Shanghai Maritime UniversityShanghai 200135China

In view of the fact that the SPH model is easy to handle the flows with the free surface of large deformation, a 2-D flow induced by vertical water entry of a 2-D structure is simulated using the two-phase SPH model. The local pressure of the boundary particles is obtained by pressure of the fluid particles nearby through a modified kernel approximation. To evaluate the accuracy of the method, water entry of a 2-D symmetric wedge with fixed separation point of the free surface on the wedge surface is simulated. The pressure distribution of the wedge at the initial stage agrees well with the analytical results available. Evolution of the free surface and the air flow in the cavity induced by the water entry are obtained. A higher speed air jet is found at the neck of the cavity when the neck of the cavity becomes smaller. For the case of a horizontal cylinder entering the water with an unknown separation point of flow on the model surface, the early stage of the water entry is simulated for the rigid body with different density. Evolution of the free surface deformation of the half-buoyant cylinder and neutrally buoyant cylinder water entry is compared with the experimental data. The effects of the density ratio and Froude number on the pinch-off of the cavity are discussed. It is found that the pinch-off time remains almost constant for different density ratio and Froude number. Meanwhile, for a given Froude number, the dimensionless pinch-off depth and the location of the cylinder at the time of pinch-off increase with the density ratio. Further, for a given density ratio, these two parameters increase with the Froude number and, however, the relative cavity shape appears to be a self-similar shape when Fr ≥8.35.

关键词： Smoothed particle hydrodynamics (SPH) two-phase water entry density ratio

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Exact Solutions to (2+1)-Dimensional Kaup-Kupershmidt Equation

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Communications in Theoretical Physics 2009年第11期52卷 795-800页

作者： LU Hai-lin LIU xi-Qiang School of Mathematical Sciences Liaocheng University Liaocheng 252059 China

In this paper, by using the symmetry method, the relationships between new explicit solutions and old ones of the （2＋1）-dimensional Kaup-Kupershmidt （KK） equation are presented. We successfully obtain more general exact travelling wave solutions for （2＋ 1）-dimensional KK equation by the symmetry method and the （G1/G）-expansion method. Consequently, we find some new solutions of （2＋1）-dimensional KK equation, including similarity solutions, solitary wave solutions, and periodic solutions.

关键词： (2+1)-dimensional Kaup-Kupershmidt equation the symmetry method the (G1/G)-expansion method exact solutions

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Remarks on the Theory of Cosmological Perturbation

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Chinese Physics Letters 2001年第11期18卷 1539-1542页

作者： lin wen-Bin Institute of High Energy Physics Chinese Academy of ScienceP.O.Box 918-4Beijing 100039

It is shown that the power spectrum defined in the synchronous gauge cannot be directly used to calculate the predictions of cosmological models on the large-scale structure of the Universe, which should be calculated... 详细信息

关键词： gauge spectrum invariant

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Biosynthesis-based artificial evolution of microbial natural products

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Science China Chemistry 2016年第9期59卷 1175-1187页

作者： Zhi lin Dandan Chen wen Liu Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China Huzhou Center of Bio-Synthetic Innovation Huzhou 313000 China

Natural products are often secondary metabolites in living organisms with a wide variety of biological activities. The diversification of their structures, aiming to the search for biologically active small molecules by expanding chemical and functional spaces, is a major area of current interest in synthetic chemistry. However, developing synthetic accessibility and efficiency often faces challenges associated with structural complexity. Synthetic biology has recently emerged and is promising to accomplish complex molecules; by contrast, the application to structural diversification of natural products relies on the understanding, development and utilization of compatible biosynthetic machinery. Here, we review the strategies primarily concerning the artificial evolution of microbial natural products whose biosynthesis features template enzymology, including ribosomaUy synthesized and post-translationally modified peptides as well as the assembly line-resultant polyketides, non-ribosomal peptides and hybrids. The establishment of these approaches largely facilitates the expansion of the molecular diversity and utility through bioengineering at different stages/levels of biosynthetic pathways.

关键词： biosynthesis artificial evolution RiPPs NRPS PKS enzymatic diversity

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A quasi-zero-stiffness isolator with a shear-thinning viscous damper

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Applied Mathematics and Mechanics(English Edition) 2022年第3期43卷 311-326页

作者： Guilin wen Yu lin Junfeng HE School of Mechanical and Electrical Engineering Guangzhou UniversityGuangzhou 510006China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004Hebei ProvinceChina

Quasi-zero-stiffness(QZS)vibration isolators have been widely studied,because they show excellent high static and low dynamic stiffnesses and can effectively solve low-frequency and ultralow-frequency ***,traditional QZS(T-QZS)vibration isolators usually adopt linear damping,owing to which achieving good isolation performance at both low and high frequencies is difficult.T-QZS isolators exhibit hardening stiffness characteristics,and their vibration isolation performance is even worse than that of linear vibration isolators under a large excitation ***,this study proposes a QZS isolator with a shear-thinning viscous damper(SVD)to improve the vibration isolation performance of the T-QZS *** force-velocity relation of the SVD is obtained,and a dynamic model is established for the *** dynamic responses of the system are solved using the harmonic balance method(HBM)and the Runge-Kutta *** vibration isolation performance of the system is evaluated using force transmissibility,and the isolator parameters are *** results show that compared with the T-QZS isolators,the proposed QZS-SVD isolator achieves the lower initial vibration isolation frequency and peak value,and exhibits better vibration isolation performance at medium and high ***,the proposed isolator can withstand a large excitation amplitude in the effective vibration isolation range.

关键词： quasi-zero-stiffness(QZS)isolator shear-thinning viscous damper(SVD) vibration isolation force transmissibility

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Regulation of blood-testis barrier dynamics by the mT0RCl/rpS6 signaling complex:an in vitro study

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Asian Journal of Andrology 2019年第4期21卷 365-374页

作者： lin-xi Li Si-wen Wu Ming Yan Qing-Quan Lian Ren-Shan Ge C Yan Cheng The Second Affiliated Hospital and Yuying Children's Hospital Wenzhou Medical University Wenzhou 325027 China The Mary M. Wohlford Laboratory for Male Contraceptive Research Center for Biomedical Research Population Council New York NY 10065 USA Jiangsu Key Laboratory of Drug Screening China Pharmaceutical University Nanjing 210009 China

During spermatogenesis, developi ng germ cells that lack the cellular ultrastructures of filopodia and lamellipodia gen erally found in migrating cells, such as macrophages and fibroblasts, rely on Sertoli cells to support their transport across the seminiferous epithelium. These in elude the transport of preleptote ne spermatocytes across the blood-testis barrier (BTB), but also the transport of germ cells, in particular developing haploid spermatids, across the seminiferous epithelium, that is to and away from the tubule lumen, depending on the stages of the epithelial cycle. On the other hand, cell junctions at the Sertoli cell-cell and Sertoli-germ cell in terface also un dergo rapid remodeli ng, invo Iving disassembly and reassembly of cell j un ctions, which, in turn, are supported by actin- and microtubule-based cytoskeletal remodeling. Interestingly, the underlying mechanism(s) and the invoIving biomolecule(s) that regulate or support cytoskeletal remodeling remain largely unknown. Herein, we used an in vitro model of primary Sertoli cell cultures that mimicked the Sertoli BTB in vivo overexpressed with the ribosomal protei n S6 (rpS6, the down stream signali ng protein of mammalian target of rapamycin complex 1 [mTORCl]) cloned into the mammalian expression vector pCI-neo, namely, quadruple phosphomimetic and constitutively active mutant of rpS6 (pCI-neo/p-rpS6-MT) versus pCI-neo/rpS6-WT (wild-type) and empty vector (pCI-neo/Ctrl) for studies. These findings provide compelling evidence that the mT0RCl/rpS6 signal pathway exerted its effects to promote Sertoli cell BTB remodeling. This was mediated through changes in the organization of actin- and microtubulebased cytoskeletons, involving changes in the distribution and/or spatial expression of actin- and microtubule-regulatory proteins.

关键词： blood-testis barrier F-actin microtubule mTORCl rpS6 Sertoli cells testis

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Transplacental induction of fatty acid oxidation in term fetal pigs by the peroxisome proliferator-activated receptor alpha agonist clofibrate

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Journal of Animal Science and Biotechnology 2016年第3期7卷 341-352页

作者： xi lin Sheila Jacobi Jack Odle Laboratory of Developmental Nutrition Department of Animal SciencesNorth Carolina State University

Background： To induce peroxisomal proliferator-activated receptor α（PPARα） expression and increase milk fat utilization in pigs at birth, the effect of maternal feeding of the PPARα agonist, clofibrate（2-（4-chlorophenoxy）-2-methyl-propanoic acid, ethyl ester）, on fatty acid oxidation was examined at ful-term delivery（0 h） and 24 h after delivery in this *** group of pigs（n = 10） was delivered from pregnant sows fed a commercial diet with or without 0.8% clofibrate for the last 7 d of gestation. Blood samples were col ected from the utero-ovarian artery of the sows and the umbilical cords of the pigs as they were removed from the sows by C-section on day 113 of ***： HPLC analysis identified that clofibric acid was present in the plasma of the clofibrate-fed sow（~4.2 μg/m L）and its offspring（~1.5 μg/m L）. Furthermore, the maternal-fed clofibrate had no impact on the liver weight of the pigs at 0 h and 24 h, but hepatic fatty acid oxidation examined in fresh homogenates showed that clofibrate increased（P 〈 0.01）^14C-accumulation in CO2 and acid soluble products 2.9-fold from [1-^14C]-oleic acid and 1.6-fold from[1-^14C]-lignoceric acid respectively. Correspondingly, clofibrate increased fetal hepatic carnitine palmitoyltransferase（CPT）and acyl-Co A oxidase（ACO） activities by 36% and 42% over controls（P 〈 0.036）. The m RNA abundance of CPT I was 20-fold higher in pigs exposed to clofibrate（P 〈 0.0001） but no differences were detected for ACO and PPARα m RNA between the two ***： These data demonstrate that dietary clofibrate is absorbed by the sow, crosses the placental membrane, and enters fetal circulation to induce hepatic fatty acid oxidation by increasing the CPT and ACO activities of the newborn.

关键词： Clofibrate Fatty acid oxidation Pigs Placenta transfer

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A fast network partition method for large-scale urban traffic networks

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控制理论与应用（英文版） 2013年第3期11卷 359-366页

作者： Zhao ZHOU Shu lin Yugeng xi Department of Automation Shanghai Jiao Tong University and Key Laboratory of System Control and Information Processing Ministry of Education

In order to control the large-scale urban traffic network through hierarchical or decentralized methods, it is necessary to exploit a network partition method, which should be both effective in extracting subnetworks and fast to compute. In this paper, a new approach to calculate the correlation degree, which determines the desire for interconnection between two adjacent intersections, is first proposed. It is used as a weight of a link in an urban traffic network, which considers both the physical characteristics and the dynamic traffic information of the link. Then, a fast network division approach by optimizing the modularity, which is a criterion to distinguish the quality of the partition results, is applied to identify the subnetworks for large-scale urban traffic networks. Finally, an application to a specified urban traffic network is investigated using the proposed algorithm. The results show that it is an effective and efficient method for partitioning urban traffic networks automatically in real world.

关键词： Traffic signal control Large-scale urban traffic networks Network partition

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