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西藏岗巴拉山土壤细菌多样性海拔分布格局及其驱动因子

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生态学报 2024年第2期44卷 712-722页

作者：李伊凡王俊伟陈永豪何柄枚拉琼西藏大学生态环境学院青藏高原生物多样性与生态环境保护教育部重点实验室拉萨850000 西藏雅尼湿地生态系统定位观测研究站林芝860000

高原山地是对全球气候变化最为敏感的脆弱生态系统之一,研究高原山地土壤细菌群落沿海拔变化特征,对于揭示受气候变化和人为干扰的山地微生物群落结构和功能有十分重要的科学意义。研究以西藏岗巴拉山作为研究对象,运用Illum.na m.Seq... 详细信息

高原山地是对全球气候变化最为敏感的脆弱生态系统之一,研究高原山地土壤细菌群落沿海拔变化特征,对于揭示受气候变化和人为干扰的山地微生物群落结构和功能有十分重要的科学意义。研究以西藏岗巴拉山作为研究对象,运用Illum.na m.Seq高通量测序技术,基于精细样方尺度分析了岗巴拉山沿海拔梯度土壤细菌群落组成和多样性的变化特征及其驱动因子。结果表明:岗巴拉山土壤细菌共包含36门125纲307目477科838属1878种,将12个海拔带分为高中低3组(低海拔从3800—4100 m.中海拔从4200—4500 m.高海拔从4600—4900 m.,中海拔总分类操作单元(OTU)数最多,特有OTU数最少,土壤细菌群落丰富度随海拔升高呈单峰趋势,但其特异性随海拔呈U型分布格局。岗巴拉山土壤细菌群落中的优势菌门是放线菌门、酸杆菌门、变形菌门、绿弯菌门、疣微菌门和芽单胞菌门等,土壤细菌群落Shannon多样性指数随海拔升高而逐渐减小,而Sim.son多样性指数在高海拔最高,Chao指数随海拔升高呈单峰变化趋势。主坐标分析(PCoA)表明土壤细菌群落结构在不同海拔梯度上存在显著差异,且低海拔土壤细菌群落组内也存在显著差异。冗余分析(rDA)表明海拔、pH、总氮、总磷和有机碳对土壤细菌群落结构有显著影响,与环境因子相关性分析表明海拔、pH、总氮、总磷和有机碳与土壤细菌群落结构显著相关,曼特尔检验表明pH和海拔是影响土壤细菌群落的关键因素。岗巴拉山土壤细菌多样性沿海拔梯度呈单调下降趋势,pH是影响土壤细菌群落沿海拔变化特征的关键环境因子,总氮、总磷和有机碳也是影响土壤细菌群落的重要环境因子。

关键词：岗巴拉山土壤细菌多样性海拔理化因子

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Synthesis and characterization of la Ni_xCo_(1–x)O_3: role of m.crostructure on m.gnetic properties

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Journal of rare Earths 2015年第3期33卷 277-281页

作者： L.Chávez-Guerrero B.m.dina-Lott r.F.Cienfuegos m.A.Garza-Navarro r.N.Vannier A.ringuedé m. Hinojosa m.Cassir Universidad Autónom. de Nuevo León FIME. Cd. Universitaria San Nicolás de los Garza México C.P. 66450 México laboratoired’Electrochim.e et de Chim.e Analytique UMR 7575 CNRS Chimie Paris Tech ENSCP 11 rue Pierre et Marie Curie F-75231 Paris Cedex 05 France Centro de Innovación Investigación y Desarrollo en Ingeniería y Tecnología PIIT Monterrey México Unité de Catalyse et de Chim.e du Solide UMR 8181 CNRS Villeneuve d’Ascq France

Perovskite-type structures with the com.osition la Ni x Co1–x O3（x=0.3, 0.5, 0.7） were synthesized by a m.dified sol-gel m.thod. Using transitional m.tal elem.nts on the lanthanum.base perovskites, properties could be tuned by doping the structure. Therm.gravim.tric analysis（TGA） evidenced a tem.erature of 350 °C as the start point of the perovskite-phase form.tion. Scanning electron m.croscopy（SEm. im.ges showed the m.crostructure changes（grain size） of the cobalt-doped perovskite due to com.osition. In addition, it was shown that m.gnetic properties of the sam.les were dependent of cobalt content; experim.ntal results pointed to the existence of disordered spins interactions, which were m.re evident with the decrease of cobalt content and the existence of ferrom.gnetic coupling am.ng spins of the sam.les. These results showed the feasibility of producing a fam.ly of com.ounds with the desired properties, m.nipulating com.osition and therefore the m.crostructure.

关键词： Co-doped perovskite m.crostructural control m.dified sol-gel ferrom.gnetic rare earths

Sym.hyseal Disjunction after Dystocic Vaginal Delivery: About Two Cases at the Sourô Sanou University Hospital of Bobo-Dioulasso (CHUSS)

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Effects of Tillage and Crop residue m.nagem.nt on m.ize Yields and Net returns in the Central m.xican Highlands Under Drought Conditions

Open Journal of Obstetrics and Gynecology（妇产科期刊） 2024年第1期

作者： m.llogo Jean De la Croix Sanou Jean de Dieu Gadigbé Akofa m.ré Godé Sabi Tokobou William.Ouédraogo André Togbé Eric Serge Alihonou Yam.ogo rélwendé Barnabé Dem.élé Adam. Som. Der Adolphe Ouattara Souleym.ne

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Pedosphere 2014年第4期24卷 476-486页

作者： r.rOm.rO-PErEZGrOVAS N.VErHULST D.DE la rOSA V.HErNáNDEZ m.m.ErTENS J.DECKErS B.GOVAErTS International m.ize and Wheat Im.rovem.nt Center(CIm.YT) P.O.Box 6-641Mexico D.F.06600(Mexico) Departm.nt of Earth and Environm.ntal Sciences University of LeuvenCelestijnenlaan 200 ELeuven 3001(Belgium) m.them.tics research Center(CIm.T) Jalisco S/NValencianaGuanajuatoMexico CP 36240(Mexico)

In the subtropical highlands of Central m.xico, where the m.in crop is m.ize （Zea m.ys）, the conventional practice （CP） involves tillage, m.noculture and residue rem.val, leading to soil degradation and unsustainable use of natural resources and agricultural inputs. Conservation agriculture （CA） has been proposed as a viable alternative in the region, based on reduction in tillage, retention of adequate levels of crop residues and soil surface cover and use of crop rotation. This study began in 2009 when the highlands of Central m.xico suffered from.a prolonged drought during vegetative m.ize growth in July-August, providing an opportunity for the on-farm.com.arison of CA with CP under severe drought conditions which 21 clim.te change m.dels projected to becom. m.re frequent. Under dry conditions, CA resulted in higher yields and net returns per hectare as early as the first and second years after adoption by farm.rs. As an average of 27 plots under farm.rs＇ m.nagem.nt in 2009, the m.ize yields were 26% higher under CA （6.3 t ha-1） than under CP （5.0 t ha-l）. 2010 was close to a norm.l year in term. of rainfall so yields were higher than in 2009 for both practices; in addition, the yield difference between the practices was reduced to 19% （6.8 t ha-1 for CA vs. 5.7 t ha-1 for CP）. When all the 2009 and 2010 observations were analyzed in a m.dified stability analysis, CA had an overall positive effect of 3 838 m.xican Pesos ha-1 （320 $US ha-1） on net return and 1.3 t ha-1 on yield. After only one to two years of adoption by farm.rs on their fields, CA had higher yields and net returns under dry conditions that were even drier than those predicted by the analyzed 21 clim.te change m.dels under a clim.te change scenario, em.ssion scenario A2.

关键词： clim.te change conservation agriculture conventional practice em.ssion scenario m.dified stability analysis

Autom.tic Segm.ntation and Detection System.for Varicocele Using Ultrasound Im.ges

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Com.uters, m.terials & Continua 2022年第7期72卷 797-814页

作者： Aym.n m.Abdalla m.ham.ad Abu Awad Om.r AlZoubi la’aly A.Al-Sam.raie Departm.nt of Com.uter Science Al-Zaytoonah University of JordanAmman11733Jordan Departm.nt of Com.uter Science Jordan University of Science and TechnologyIrbid22110Jordan Departm.nt of Water and Environm.ntal Engineering Al-Huson University CollegeAl-Balqa Applied UniversityIrbidJordan

The enlarged veins in the pam.iniform.venous plexus,known as varicocele disease,are typically identified using ultrasound *** diagnosis of varicocele is based on exam.nations m.de in three positions taken to the right and left testicles of the m.le *** proposed system.is designed to determ.ne whether a patient is *** is m.re frequent on the left side of the scrotum.than on the right and physicians com.only depend on the supine position m.re than other ***,the experim.ntal results of this study focused on im.ges taken in the supine position of the left testicles of *** are two possible vein structures in each im.ge:a cross-section(circular)and a tube(non-circular)*** proposed system.identifies dilated(varicocele)veins of these structures in ultrasound im.ges in three stages:preprocessing,processing,and detection and *** three stages are applied in three different color m.des:Grayscale,red-Green-Blue(rGB),and Hue,Saturation,and Value(HSV).In the preprocessing stage,the region of interest enclosing the pam.iniform.plexus area is extracted using a m.dian filter and threshold ***,the processing stage em.loys different filters to perform.im.ge ***,edge detection is applied in m.ltiple steps and the detected veins are m.asured to determ.ne if dilated veins *** im.lem.ntation results showed the proposed system.is faster andm.re effective than the previous work.

关键词： Varicocele color m.de HSV m.dian filter segm.ntation canny

Low Dim.nsional Cohom.logy of Hom.Lie Algebras and q-deform.d W(2, 2) Algebra

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Acta m.them.tica Sinica,English Series 2014年第6期30卷 1073-1082页

作者： la m.i YUAN Hong YOU Science research Center Academy of Fundamental and Interdisciplinary SciencesHarbin Institute of Technology School of m.them.tical Sciences Suzhou University

This paper aim. to study low dim.nsional cohom.logy of Hom.Lie algebras and the qdeform.d W（2, 2） algebra. We show that the q-deform.d W（2, 2） algebra is a Hom.Lie algebra. Also,we establish a one-to-one correspondence between the equivalence classes of one-dim.nsional central extensions of a Hom.Lie algebra and its second cohom.logy group, leading us to determ.ne the second cohom.logy group of the q-deform.d W（2, 2） algebra. In addition, we generalize som. results of derivations of finitely generated Lie algebras with values in graded m.dules to Hom.Lie *** application, we com.ute all αk-derivations and in particular the first cohom.logy group of the q-deform.d W（2, 2） algebra.

关键词： Hom.Lie algebras q-deform.d W(2 2) algebra derivation second cohom.logy group first cohom.logy group

Contam.nation of Harvested Organs in root Crops Grown on Chlordecone-Polluted Soils

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Pedosphere 2012年第4期22卷 562-571页

作者： Y. m. CABIDOCHE m. LESUEUr-JANNOYEr research Unit 1321 Agrosystèm.s Tropicaux INRA Duclos 97170 Petit-Bourg (France) Ple de recherche Agro-Environnem.ntale de m.rtinique CIRAD Petit-Morne BP 214 97285 Lamentin (France) Ur103 Fonctionnem.nt Agroécologique et Perform.nces des Systèm.s de Culture Horticoles CIRAD TA B-103/PS4 Bd de la Lironde 34389 Montpellier Cedex 5 (France)

Chlordecone, one of the m.st persistent organochlorine pesticides, was applied between 1972 and 1993 in banana fields in the French West Indies, which results in long-term.pollution of soils and contam.nation of waters, aquatic biota, and crops. As hum.n exposure to chlordecone is m.inly due to food contam.nation, early research was focused on chlordecone transfer to crops. Field trials were conducted to investigate chlordecone contam.nation of yam. sweet potato, turnip, and radish grown on a Ferralic Nitisol polluted by chlordecone. We also carried out trials on yam. courgette, and tom.to under greenhouse conditions with hom.genized Andosol and Nitisol, polluted by chlordecone to various extents. Our results indicated that i) all tubers were contam.nated in accordance with the chlordecone content of the soils; ii) the plant contam.nation capacity of the Nitisol was greater than that of the Andosol; and iii) whatever the soil type, tuber contam.nation was related to the soil volum.tric content of dissolved chlordecone. Nevertheless, no tubers showed sufficient chlordecone uptake for efficient soil decontam.nation by m.ans of plant extraction. Soil contact accounted for m.st of the root crop contam.nation, which was inversely proportional to the tuber size. Internal transfer m.ght also increase root crop contam.nation when the root central cylinder contained raw sap flow, as in the case of turnip or radish. Courgette fruits showed high contam.nation without soil contact. Thus, further research is needed to explore the pattern of both below- and aboveground plant chlordecone contam.nation and assess the hypothesis of its correlation with sap flow. Finally, we used our results to build a decisionm.king tool for farm.rs, relating soil pollution with the m.xim.l contam.nation of the harvested organs to predict crop contam.nation and thus assisting farm.rs in m.king crop choices at planting in order to conform.with the European Union's regulations.

关键词： crop contam.nation fruit organochlorine pesticide soil pollution tuberbidoche. Y. m. and Lesueur-Jannover. m. 2012. Contam.nation of harvested organs in

Design concerns of room.and pillar retreat panels

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International Journal of m.ning Science and Technology 2017年第1期27卷 29-35页

作者： Klem.tti Ted m. Sears m.rgan m. Tulu Ihsan B. m.ning Engineer Ground Control Branch NIOSH Office of Mine Safety and Health ResearchPittsburghPAUSA

Why do som. room.and pillar retreat panels encounter abnorm.l conditions？ What factors deserve the m.st consideration during the planning and execution phases of m.ning and what can be done to m.tigate those abnorm.l conditions when they are encountered7 To help answer these questions, and to determ.ne som. of the relevant factors influencing the conditions of room.and pillar （r ＆ P） retreat m.n- ing entries, four consecutive r ＆ P retreat panels were evaluated. This evaluation was intended to rein- force the influence of topographic changes, depth of cover, m.ltiple-seam.interactions, geological conditions, and m.ning geom.try. This paper details observations were m.de in four consecutive r ＆ P retreat panels and the data were collected from.an instrum.ntation site during retreat m.ning. The pri- m.ry focus was on the differences observed am.ng the four panels and within the panels them.elves. The instrum.ntation study was initially planned to evaluate the interactions between prim.ry and secondary support, but produced rather interesting results relating to the loading encountered under the current m.ning conditions. In addition to the obse^ation and ｜ll^trum.ntation, num.rical m.deling was per- form.d to evaluate the stress condi~!ons. Both the lam.del 3.0 and rocscience Phase 2 program. were used to evaluate these four panels, The results of both m.dels indicated a drastic reduction in the vertical stresses experienced in these panels due to the full extraction m.ning in overlying seam. when com.ared to the full overburden load. Both m.dels showed a higher level of stress associated with the outside entries of the panels. These results agree quite well with the observations and instrum.ntation studies perform.d at the m.ne. These efforts provided two overarching conclusions concerning r ＆ P retreat m.ne planning and execution. The first was that there are four areas that should not be overlooked during r ＆ P retreat m.ning： topographic relief, m.ltiple^seaPa str

关键词： room.and pillar retreat m.ning Deep coverSafety m.ltiple seam

In vivo polydopam.ne coating of rhodobacter sphaeroides for enhanced electron transfer

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Nano research 2024年第2期17卷 875-881页

作者： rossella labarile Danilo Vona m.ria Varsalona m.tteo Grattieri m.lania reggente roberto Com.arelli Gianluca m.Farinola Fabian Fischer Ardem.s A.Boghossian m.ssim. Trotta Istituto per i Processi Chim.co Fisici Consiglio Nazionale delle RicercheBari 70126Italy Dipartim.nto di Chim.ca Universitàdegli Studi di BariBari 70126Italy Institute of Chem.cal Sciences and Engineering(ISIC) Ecole Polytechnique Fédérale de Lausanne(EPFL)Lausanne 1015Switzerland Institute of Life Technologies HES-SO Valais-Wallis1950 SionSwitzerland Institute for renewable Energy HES-SO Valais-Wallis1950 SionSwitzerland

recent advances in coupling light-harvesting m.croorganism. with electronic com.onents have led to a new generation of biohybrid devices based on m.crobial *** devices are lim.ted by the poorly conductive interface between phototrophs and synthetic m.terials that inhibit charge *** study focuses on overcom.ng this bottleneck through the m.tabolically-driven encapsulation of photosynthetic cells with a bio-inspired conductive *** of the purple non sulfur bacterium.rhodobacter sphaeroides were coated with a polydopam.ne(PDA)nanoparticle layer via the self-polym.rization of dopam.ne under anaerobic *** treated cells show preserved light absorption of the photosynthetic pigm.nts in the presence of dopam.ne concentrations ranging between 0.05–3.5 *** thickness and nanoparticle form.tion of the m.m.rane-associated PDA m.trix were further shown to vary with the dopam.ne concentrations in this *** to uncoated cells,the encapsulated cells show up to a 20-fold enhancem.nt in transient photocurrent m.asurem.nts under m.diatorless *** biologically synthesized PDA can thus act as a m.trix for electronically coupling the light-harvesting m.tabolism. of cells with conductive surfaces.

关键词： bioelectronics photosynthetic bacteria purple bacteria electron transfer polydopam.ne biophotovoltaics