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An unprotected vulnerable relict subtropical conifer-Keteleeria evelyniana: Its forests, populations, growth and endangerment by invasive alien plant species in China

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Plant Diversity 2024年第5期46卷 648-660页

作者： Cindy Q.Tang Min-Rui Du Huan-Chong Wang You-Cai shi Jia-Le Zeng Shu-Li Xiao Peng-Bin Han Jian-Ran Wen shi-qian yao Ming-Chun Peng Chong-Yun Wang Yong-Ping Li Jordi López-Pujol Institute of Ecology and Geobotany College of Ecology and Environmental ScienceYunnan UniversityBuilding#3Guozhong DalouDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina College of Life Sciences Yunnan UniversityShengming Kexueyuan Building#2Chenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina College of Natural Resources Yunnan UniversityChenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina Botanic Institute of Barcelona(IBB CSIC-CMCNC)Passeig del Migdia s/nBarcelona 08038CataloniaSpain Escuela de Ciencias Ambientales Universidad Espíritu Santo(UEES)Samborondon 091650Ecuador

Relict subtropical coniferous forests in China face severe fragmentation,resulting in declining populations,and some are under significant threat from invasive alien *** the crucial importance of understanding forest dynamics,knowledge gaps persist,particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria *** this study,we investigated the impact of invasive plants on the regeneration of forests dominated by ***,a subtropical relict species in southwestern *** this purpose,we characterized forest dynamics of 160 forest plots featuring *** as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of *** identified four distinct forest types in which *** was *** found that radial growth of *** trees is faster in younger ageclasses today than it was for older trees at the same *** population structure of *** in each forest type exhibited a multimodal age-class ***,three forest types lacked established saplings younger than 10 years old,a situation attributed to the dense coverage of the invasive alien Ageratina *** invasive species resulted in a reduction of understory species ***,our analysis uncovered a significant negative correlation in phylogenetic relatedness(net relatedness index)between native and invasive alien plant species in eastern *** suggests closely related invasive species face heightened competition,hindering successful *** together,our findings indicate that successful establishment and habitat restoration of *** seedling/saplings require effective measures to control invasive plants.

关键词： Keteleeria evelyniana Age structure Regeneration Species diversity Invasive alien species Phylogenetic relatedness

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Synthesis and Crystal Structure of Binuclear Complex of Copper(Ⅱ)Chloroacetate with Acetamine

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Chinese Journal of Structural Chemistry 1999年第2期18卷 19-22页

作者： shi qian WANG yao Yu ② TANG Zong Xun shi Qi Zhen (Department of Chemistry, Northwest University, Xi’an 710069) 西北大学化学系陕西西安 710069

The title complex, Cu 2(O 2CCH 2Cl) 4 OC(NH 2)CH 3 2, crystallizes in space group P2 1/a with a=7.616(4), b=18.665(5), c=7.949(5) , β=106.29(5)°. V=1084(1)  3, Z=2, M r=619.19, D c =1.896 g/cm 3; μ =25.05 cm -1 and F(000)=620.00, R =0.045 and R w =0.054 for 1807 observable reflections. X ray crystal structure analysis revealed that two Cu atoms are bridged by four chloroacetate groups, and the acetamine ligands are bonded by O(carboxide) to the terminal Cu atoms of each dimeric unit. The coordination geometry of Cu atom is a distorted octahedral configuration. The distance between the two Cu atoms is 2.648(1) .

关键词： copper(Ⅱ) chloroacetate binuclear complex crystal structure

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An investigation on topologies of hybrid manifold,impinging-jet nozzle and micro-pin-fin heat sinks

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Science China(Technological Sciences) 2024年第4期67卷 1061-1076页

作者： shi qianLei yao XiaoLe LIU qian QIN Le JU Xing XU Chao Key Laboratory of Power Station Energy Transfer Conversion and System of MOE North China Electric Power UniversityBeijing 102206China

The hybrid manifold micro-pin-fin(MMPF)heat sink combined nozzle jets is an option for large-scale integrated circuits(LSI).The demond for uniform and ultra-high heat flux removal by MMPF heat sink has not been adequately *** work aims to solve the problem of fluid *** proposed basic tiling topologies,including square,regular hexagon,30°rhombus,and 60°rhombus topologies,provide different organized fluid flows and heat transfer *** present study focuses on comparing these topologies according to independent porous medium parameters,such as nozzle pore size D_(Z),flow pore size D_(X,Y),and porosityε.The results show that the square topology achieves the smallest total thermal resistance R_(tot)value of0.0975×10^(-4)K m^2/W,while the hexagon topology achieved the highest value of COP/?T,which was 2033.9 K^(-1).According to the sensitivity analysis results,the optimal total thermal resistance can be obtained by balancing the influences of nozzle pore size,flow pore size,and *** optimal pressure drop can be obtained by maximizing the porosity.

关键词： heat sink ultra-high heat flux manifold micro-pin-fin impinging-jet topology

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Diarrhea induced by insufficient fat absorption in weaned piglets:Causes and nutrition regulation

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Animal Nutrition 2024年第1期16卷 299-305页

作者： Yuying Li Pengjun shi Kang yao qian Lin Mansheng Wang Zhenping Hou Wenjie Tang Hui Diao Institute of Bast Fiber Crops Chinese Academy of Agricultural Sciences Institute of Subtropical Agriculture Chinese Academy of Sciences Hunan Province Key Laboratory of Animal Nutritional Physiology and Metabolic Process Animal Breeding and Genetics Key Laboratory of Sichuan Province Livestock and Poultry Biological Products Key Laboratory of Sichuan Province Sichuan Animal Science Academy Sichuan Animtech Feed Co. Ltd

Fat is one of the three macronutrients and a significant energy source for piglets. It plays a positive role in maintaining intestinal health and improving production performance. During the weaning period,physiological, stress and diet-related factors influence the absorption of fat in piglets, leading to damage to the intestinal barrier, diarrhea and even death. Signaling pathways, such as fatty acid translocase(CD36), pregnane X receptor(PXR), and AMP-dependent protein kinase(AMPK), are responsible for regulating intestinal fat uptake and maintaining intestinal barrier function. Therefore, this review mainly elaborates on the reasons for diarrhea induced by insufficient fat absorption and related signaling pathways in weaned-piglets, with an emphasis on the intestinal fat absorption disorder. Moreover, we focus on introducing nutritional strategies that can promote intestinal fat absorption in piglets with insufficient fat absorption-related diarrhea, such as lipase, amino acids, and probiotics.

关键词： Weaned piglet Diarrhea Fat absorption Nutrient regulation

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A high-performance lithium anode based on N-doped composite graphene

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Rare Metals 2024年第3期43卷 1030-1036页

作者： Can Jiao Hao-Bo Sun Li Zhang Shang-qian Zhao Guo-yao Pang Chun-Rong Zhao shi-Gang Lu General Research Institute for Nonferrous Metals Beijing100088China China Automotive Battery Research Institute Co.Ltd Beijing101407China

Lithium(Li)metal is the most promising electrode for next-gene ration rechargeable *** order to push the commercialization of the lithium metal batteries,a kind of nitrogen(N)-doped composite graphene(NCG)adopted as the Li plating host was prepared to regulate Li metal nucleation and suppress dendrite ***,a new kind of sandwich-type composite lithium metal(STCL)electrode was developed to improve its *** STCL electrode can be used as convenient as a piece of Li foil but no dendrite *** a symmetric battery,the STCL electrode cycled for more than 4500 h with the overpotential of less than 40 *** due to the creative design,the STCL promises the Li-S battery with a prolonged cycling lifespan.

关键词： Lithium metal anode Lithiophilic N-doped composite graphene Sandwich-type composite lithium metal electrode

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The tangential k-Cauchy-Fueter type operator and Penrose type integral formula on the generalized complex Heisenberg group

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 181-190页

作者： REN Guang-zhen shi Yun KANG qian-qian Department of Mathematics Zhejiang International Studies UniversityHangzhou 310023China Department of Mathematics Zhejiang University of Science and TechnologyHangzhou 310023China

The tangential k-Cauchy-Fueter operator and k-CF functions are counterparts of the tangential Cauchy–Riemann operator and CR functions on the Heisenberg group in the theory of several complex variables,*** this paper,we introduce a Lie group that the Heisenberg group can be imbedded into and call it generalized complex *** investigate quaternionic analysis on the generalized complex *** also give the Penrose integral formula for k-CF functions and construct the tangential k-Cauchy-Fueter complex.

关键词： the generalized complex Heisenberg group the tangential k-Cauchy-Fueter type operator Penrose-type integral formula

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Study on a probabilistic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding

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Advances in Manufacturing 2024年第2期12卷 288-299页

作者： Zhao-Qing Zhang Kai-Ning shi yao-yao shi Yi-Hui Song Zhe He Ya-Song Pu School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an710072People’s Republic of China Key Laboratory of High Performance Manufacturing for Aero Engine(Northwestern Polytechnical University) Ministry of Industry and Information TechnologyXi’an710072People’s Republic of China Engineering Research Center of Advanced Manufacturing Technology for Aero Engine(Northwestern Polytechnical University) Ministry of EducationXi’an710072People’s Republic of China

Profile grinding is the most crucial method for the ultra-precision machining of special-shaped ***,profile grinding produces a unique machining profile,and many random factors in the machining process lead to complex surface *** this study,the structural and probabilistic characteristics of the profile grinding of a special-shaped surface were analyzed,and a probabilistic algorithm for the forming and 3D characterization of special-shaped surfaces under profile grinding was *** forming process of a GH738 blade tenon tooth surface was considered as an example to demonstrate the *** comparison results showed that the simulation results had similar surface characteristics to the measurement results,and the relative error range of the 3D roughness parameter was 0.21%–19.76%,indicating an accurate prediction and characterization of the complex special-shaped surface under the action of multiple factors.

关键词： Special-shaped surface Profile grinding Surface morphology 3D characterization

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Forest characteristics,population structure and growth trends of threatened relict Pseudotsuga forrestii in China

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Plant Diversity 2023年第4期45卷 422-433页

作者： Cindy Q.Tang shi-qian yao Peng-Bin Han Jian-Ran Wen Shuaifeng Li Ming-Chun Peng Chong-Yun Wang Tetsuya Matsui Yong-Ping Li Shan Lu Yuan He Institute of Ecology and Geobotany College of Ecology and Environmental ScienceYunnan UniversityBuilding ShixunChenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunmingYunnan 650504China College of Life Sciences Yunnan UniversityShengming Kexueyuan Building#2Chenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunmingYunnan 650504China Institute of Highland Forest Science Chinese Academy of ForestryKunmingYunnan 650224China Forestry and Forest Products Research Institute Forest Research and Management OrganizationMatsunosato 1Tsukuba-shiIbaraki-ken305-8687Japan Faculty of Life&Environmental Sciences University of Tsukuba1-1-1 TennodaiTsukubaIbaraki305-8572Japan College of Natural Resources Yunnan UniversityChenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunmingYunnan 650504China Forestry and Grassland Bureau of Diqing Tibetan Autonomous Prefecture 1st Floor of Government BuildingShengping TownDeqing CountyYunnan 674500China Forestry and Grassland Bureau of Weixi Lisu Autonomous County Nanjian Dao#7Baohe TownWeixi Lisu Autonomous CountyYunnan 674600China

Pseudotsuga forrestii is a relict evergreen coniferous tree species in Pinaceae endemic to *** tree numbers have greatly decreased due to deforestation,over-utilization and habitat *** we clarify *** community types,structure,species diversity,seedling recruitments and growth *** identified four *** community types:(1)Pseudotsuga forrestii-Quercus guyavifolia-Acer davidii evergreen coniferous and broad-leaved mixed forest;(2)Pseudotsuga forrestii-Pinus yunnanensis-Quercus guyavifolia evergreen coniferous and broad-leaved mixed forest;(3)Pseudotsuga forrestii evergreen coniferous forest;(4)Pseudotsuga forrestii-Abies georgei *** evergreen coniferous *** forests are characterized by both warm temperate and temperate *** diversity,Pielou evenness,Shannon-Wiener diversity indices ranged from 0.75 to 0.76,0.74-0.81,and 1.62-1.93,respectively,with no significant differences among the four forest *** forest stratification was *** canopy layer was generally 10-25 m tall,with the emergent layer reached 25-42 *** and age structures of *** showed multimodal *** maximum age *** was 570 years with a DBH of 143 *** growth of annual ring width of *** was slow,and generally decreased with age,whereas the basal area at the breast height increased with *** seedlings/saplings were mainly found in unstable *** of *** depends on moderate natural ***,we provide recommendations for *** conservation.

关键词： Pseudotsuga forrestii Community structure Species diversity Population structure Regeneration Growth trend

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Value of multiple models of diffusion-weighted imaging to predict hepatic lymph node metastases in colorectal liver metastases patients

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World Journal of Gastroenterology 2024年第4期30卷 308-317页

作者： Hai-Bin Zhu Bo Zhao Xiao-Ting Li Xiao-Yan Zhang qian yao Ying-shi Sun Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of RadiologyPeking University Cancer Hospital and InstituteBeijing 100142China Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of PathologyPeking University Cancer Hospital and InstituteBeijing 100142China

BACKGROUND About 10%-31% of colorectal liver metastases(CRLM)patients would concomitantly show hepatic lymph node metastases(LNM),which was considered as sign of poor biological behavior and a relative contraindication for liver *** to now,there’s still lack of reliable preoperative methods to assess the status of hepatic lymph nodes in patients with CRLM,except for pathology examination of lymph node after *** To compare the ability of mono-exponential,bi-exponential,and stretchedexponential diffusion-weighted imaging(DWI)models in distinguishing between benign and malignant hepatic lymph nodes in patients with CRLM who received neoadjuvant chemotherapy prior to *** In this retrospective study,97 CRLM patients with pathologically confirmed hepatic lymph node status underwent magnetic resonance imaging,including DWI with ten b values before and after *** parameters,such as the apparent diffusion coefficient from the mono-exponential model,and the true diffusion coefficient,the pseudo-diffusion coefficient,and the perfusion fraction derived from the intravoxel incoherent motion model,along with distributed diffusion coefficient(DDC)andαfrom the stretched-exponential model(SEM),were *** parameters before and after chemotherapy were compared between positive and negative hepatic lymph node groups.A nomogram was constructed to predict the hepatic lymph node *** reliability and agreement of the measurements were assessed using the coefficient of variation and intraclass correlation *** Multivariate analysis revealed that the pre-treatment DDC value and the short diameter of the largest lymph node after treatment were independent predictors of metastatic hepatic lymph nodes.A nomogram combining these two factors demonstrated excellent performance in distinguishing between benign and malignant lymph nodes in CRLM patients,with an area under the curve of ***,parameters from SEM sho

关键词： Colorectal cancer Individualized treatment Diffusion magnetic resonance imaging Intravoxel incoherent motion Liver

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The homogenous growth of Co-based coordination compound on graphene nanosheet for high-performance K-organic battery and its reaction mechanism

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Rare Metals 2024年第4期43卷 1622-1634页

作者： qian-qian Peng Yi-Ting Wang Shuo Qi yao Xiao Yong Wang Shuang-qiang Chen School of Environmental and Chemical Engineering Shanghai UniversityShanghai200444China School of Chemistry and Materials Engineering Wenzhou UniversityWenzhou325035China

Metal coordination compounds(MCCs)are gaining popularity for potassium-ion batteries(PIBs)owing to their tuneable structure,multiple reaction sites,low cost and unique ***,they are generally subjected to intrinsic features of the sluggish ionic diffusion coefficient,low electronic conductivity and slow ***,a new MCC material of cobalt-1,3,5-trioxy-2,4,6-triamino-benzo(Co-TB)coordination compound was synthesized and homogenously grown on the surface of graphene nanosheets(GNS),forming a Co-TB@GNS composite with enhanced electronic conductivity and flexible *** from the overall enhanced conductivity,high surface area and abundant activated K-storage sites,Co-TB@GNS electrodes have exhibited superior cycling performance with high reversible capacities(312 mAh·g^(-1)after 100 cycles at 100 mA·g^(-1),224 mAh·g^(-1)after 500 cycles at 1 A·g^(-1))and better rate performances compared with the pure Co-TB compound when served as PIB's ***,multiple in-situ measurement techniques have jointly confirmed that the organic functional groups(C=O,C=N and C=C of benzene rings)and Co^(2+)in Co-TB are the main reversible K-storage sites,including in-situ Fourier transform infrared spectroscopy(FTIR)and X-ray diffraction(XRD),and partial capacity contribution is originated from GNS by the apparent K-storage behavior in the in-situ XRD pattern,proving the possibility of K-storage for metal-organic materials.

关键词： Metal coordination compounds Potassiumion battery Cobalt coordination compound K-storage mechanism

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