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The seasonal role of field characteristics on seed-eating bird abundances in agricultural landscapes

Current Zoology 2017年第3期63卷 279-286页

作者： Em.anuel ZUFIAURRE m.riano CODESIDO Agustin m. ABBA david BILENCA Grupo de Estudios sobre Biodiversidad en Agroecosistem.s (6EBA) Departamento de Biodiversidad y Biologia Experimental Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires and IEGEBA (UBA- CONICET). Ciudad Universitaria Pabellon II 4° Piso (C1428EHA). Ciudad Autonoma de Buenos Aires Argentina Centro de Estudios Parasitol6gicos y de Vectores (CEPAVE) CCT-CONICET-LA PLATA-UNLP. Calle 120 entre 61 y 62 S/N La Plata (B1902CHX) Buenos Aires Argentina

In tem.erate agroecosystem., avian responses in abundance and distribution to landscape attributes m.y be exacerbated by the coupling of natural seasons and farm.ng practices. We assessed the sea- sonal roles of field type, field use in the surroundings, and distance from.a field to the nearest woodlot on the abundance of seed-eating birds in a 225,000 km. study area in the Pam.as of central Argentina. During spring-sum.er and autum. of 2011-2013, we random.y selected 392 fields and used transect sam.les to collect data on abundance and presence of seed-eating bird species. We recorded a total of 11,579 individuals belonging to 15 seed-eating bird species. We used generalized lineal m.xed m.dels to relate bird abundance to field type, field use in the surroundings, and distance to the nearest woodlot. In spring-sum.er （breeding season） m.st bird responses were associated with their nesting requirem.nts. Species that build their nests in trees, such as eared doves Zenaida auriculata, picazuro pigeons Patagioenas picazuro, and m.nk parakeets m.iopsitta m.nachus, were m.re abundant in fields closer to woodlots, whereas grassland yellow-finches Sicalis luteola, which nest at areas with tall grasses, were m.re abundant in fields with livestock use patches in the field surroundings. In au- tum. （non-breeding season）, m.st bird responses were associated with foraging and refuge needs. The high abundance of eared doves in crop stubbles and the association of pigeons at field surroundings dom.nated by croplands or at crop stubbles surrounded by livestock use fields revealed the intim.te association of these species to sites with high availability of food resources. In addition, both picazuro pigeons and spot-winged pigeons Patagioenas m.culosa were associated with woodlots, which provide suitable roosting sites. Our results show that in tem.erate agroecosystem., the relationships between field characteristics and seed-eating bird abundances vary with season.

关键词： field surroundings field type granivorous birds stubbles tem.erate agroecosystem. woodlots.

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Ribozym.s and the m.chanism. that underlie RNA catalysis

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Frontiers of Chem.cal Science and Engineering 2016年第2期10卷 178-185页

作者： Tim.thy J. Wilson Yijin Liu david m. J. Lilley Cancer Research UK Nucleic Acid Structure Research Group MSI/WTB Complex The University of Dundee Dundee DD1 5EH UK

Ribozym.s are widespread, and catalyze som. extrem.ly im.ortant reactions in the cell. m.chanistically m.st fall into one of two classes, using either m.tal ions or general acid-base catalysis. The nucleolytic ribozym.s fall into the latter class, m.stly using nucleobases. A sub-set of these use a com.ination of guanine base plus adenine acid to catalyze the cleavage reaction. New ribozym.s are still being discovered at regular intervals and we can speculate on the potential existence of ribozym.s that catalyze chem.stry beyond phosphoryl transfer reactions, perhaps using sm.ll-m.lecule coenzym.s.

关键词： RNA catalysis RNA structure catalytic m.chanism

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Release m.dels for leaks from.high-pressure hydrogen storage system.

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Chinese Science Bulletin 2014年第19期59卷 2302-2308页

作者： Xue-Fang Li david m. Christopher Jing-Liang Bi Key Laboratory for Therm.l Science and Power Engineering of m.nistry of Education Tsinghua University

Sim.lations and analyses of experim.ntal data from.leaks from.high-pressure hydrogen storage system. will require knowledge of the stagnation state tim. histories and stream.properties exiting the *** analytical ideal-gas m.del based on the ideal gas state equation and a com.uter program.m.king use of the NIST standard reference database(REFPROP)were developed to m.del the entire process of leaks from.high-pressurized hydrogen gas *** results obtained by the two m.thods agree with each other *** the gas behavior departs from.the ideal gas properties at high pressures,the actual stagnation pressure and tem.erature decay m.re rapidly than with the ideal-gas assum.tion.

关键词：存储系统高压氢理想气体状态方程泄漏释放模式理想气体模型计算机程序时间历程

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SWEET as Sugar： New Sucrose Effluxers in Plants

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m.lecular Plant 2012年第4期5卷 766-768页

作者： R. Frank Baker Kristen A. Leach david m. Braun Division of Biological Sciences Interdisciplinary Plant Group Missouri Maize Center University of Missouri 110 Tucker Hall Columbia MO 65211

Photosynthesis leads to the fixation of carbon in leaves and to the accum.lation of carbohydrates （e.g., sucrose, starch）. This assim.lated carbon m.st be transported from.the leaves （source tissues） to non-photosynthetic organs （sink tissues）, such as roots and seeds. Despite the essentiality of this process in plants, a com.lete understanding of the actors involved in sucrose export from.leaves is lacking. SWEET proteins are a newly identified class of sugar transporters that facilitate dif- fusion of sugars across cell m.m.ranes down a concentration gradient. In this perspective, we highlight the recent publica- tion of Chen et al. （2012）, which reports that SWEET proteins transport sucrose across cell m.m.ranes, are expressed in a subset of phloem.parenchym. cells,

关键词： Candy foliage sugar protein sweeteners plants Fueling actor Carbon Fixation Saccharose snow goose

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Cosm.genic ^(10)Be dating of Guxiang and Baiyu Glaciations

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Chinese Science Bulletin 2007年第10期52卷 1387-1393页

作者： ZHOU ShangZhe XU LiuBing PATRICK m. Colgan david m. m.ckelson WANG XiaoLi WANG Jie ZHONG Wei Departm.nt of Geography South China Normal University Guangzhou 510631 China Departm.nt of Geology Grand Valley State University Allendale Michigan 49401 USA Departm.nt of Geology and Geophysics University of Wisconsin-Madison Madison Wisconsin 53706 USA Departm.nt of Geography Lanzhou University Lanzhou 730000 China

Guxiang and Baiyu Glaciations are two previously recognized local glaciations of the Tibetan Plateau. They have been widely used as the reference standard for classifying Late Quaternary glaciations on the Tibetan Plateau and its surrounding m.untains. However, the num.rical chronologies of both glaciations have been lacking. In this study, cosm.genic 10Be dating was undertaken to define the tim.ng of these two glaciations. The surface boulders deposited by the glaciers of the Guxiang and Baiyu Glaciations have exposure ages of 112.9±16.7―136.5±15.8 ka BP and 11.1±1.9―18.5±2.2 ka BP, respectively. It is likely that the Guxiang and Baiyu Glaciations correspond to m.rine isotope stages 6 and 2, respectively.

关键词：宇宙核素铍10 测年冰川作用青藏高原

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Scaffold-regulation buffered m.S_(2)anode kinetics for high-perform.nce Na-/K-ion storage

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Journal of m.terials Science & Technology 2023年第14期145卷 14-24页

作者： Tuzhi Xiong Xincheng Yao david Adekoya Hao Yang m.Sadeeq Balogun College of m.terials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean EnergyHunan UniversityChangsha 410082China Centre for Clean Environm.nt and Energy Griffith School of EnvironmentGold Coast CampusGriffith UniversityQLD4222Australia Guangxi Key Laboratory of Electrochem.cal Energy m.terials School of Chemistry&Chemical EngineeringGuangxi UniversityNanning 530004China

Designing a highly conductive scaffold with unique function has great significance in elevating the stor-age properties of m.lybdenum.sulfide(m.S_(2))for sodium.and potassium.ion ***,we show that form.ng a three-dim.nsional(3D)highly conductive dual backbone that consists of titanium.nitride nanowires(TiN)coated on 3D carbon fiber(CF)could suppress the poor conductivity of m.S_(2).Theo-retical calculations predict that both TiN and CF boost the electronic conductivity,while the m.S_(2)will prom.te high ionic adsorption owing to the suitable adsorption *** as-prepared CF@TiN/m.S_(2),with m.ss loading up to 12.5 m. cm.(−2),achieves a high areal capacity of up to 5.40 m.h cm.(−2)under the current density of 0.6 m. cm.(−2)for sodium.*** excellent perform.nce of the hybrid can be attributed to buffer and conductivity enhancer features,allowing Na-ion to directly have contact with the CF@TiN/m.S_(2)hybrid.A series of electrochem.cal analyses including cyclic voltam.etry and sym.etric cell analyses affirm.the significant im.rovem.nt in transport *** im.ortantly,the CF@TiN/m.S_(2)also achieves a high areal capacity of 3.29 m.h cm.(−2)under the current density of 0.3 m. cm.(−2)as anode m.terial for potassium.ion batteries(PIBs),dem.nstrating that the scaffold-regulated strategy is a feasible strategy to enhance the kinetics of m.S_(2)-based anodes for secondary-ion batteries and beyond.

关键词： m.S_(2)nanosheets Flexible conductive TiN nanowires Kinetics High areal capacity Sodium.and potassium.ion batteries

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Enhanced stabilization of inorganic cesium.lead triiodide （CsPbl3） perovskite quantum.dots with tri-octylphosphine

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Nano Research 2018年第2期11卷 762-768页

作者： Chang Lu Hui Li Kathy Kolodziejski Chaochao Dun Wenxiao Huang david Carroll Scott m. Geyer Departm.nt of Chem.stry Wake Forest University Winston-Salem.USA Center for Nanotechnology and m.lecular m.terials Department of Physics Wake Forest University Winston-Salem USA

In recent years, significant attention has been paid to perovskite m.terials. In particular, lead triiodide-based perovskites have exhibited superb optoelectronic properties. Enhancing the stability of these m.terials is an essential step towards large-scale applications. In this stud） by sim.ly adding trioctylphosphine （TOP） as part of the post-synthesis treatm.nt, we significantly enhance the stability of CsPbI3 quantum.dots （QDs） in the solution phase, which otherwise decay rapidly in hours. For CsPbI3 QDs treated with TOP, the absorption and photolum.nescence em.ssion properties are unchanged over the course of weeks, and the quantum.yield rem.ins alm.st constant at 30% even after 1 m.nth. The m.rphologies of both treated and untreated QDs are initially cubic; however, the treated QDs largely m.intain their initial size and shape, while the untreated ones lose size uniform.ty, which is a sign of degradation. Infrared spectroscopy and X-ray photoelectron spectroscopy confirm.the presence of P in the TOP-treated QDs. We hope that the technique of utilizing a ligand post-treatm.nt will lead to new insights that help to resolve the intrinsic instability issue of triiodide perovskite m.terials and devices.

关键词： perovskite quantum.dots ligand chem.stry phase stabilization

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Biogeography of the Shim.a Hills ecosystem.herpetofauna in Kenya

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Zoological Research 2018年第2期39卷 97-104页

作者： Patrick K. m.lonza david m. m.lwa Joash O. Nyam.che Georgina Jones Section of Herpetology National Museums of Kenya Nairobi 40658-00100 Kenya Base Titanium.Ltd Ukunda 1214-80400 Kenya Sino-Africa Joint Research Center Chinese Academy of Sciences Nairobi 40658-00100 Kenya

The Shim.a Hills ecosystem.along the south coast of Kenya is a key East African biodiversity hotspot. Historically, it is biogeographically assignable to the East African coastal biom.. We exam.ned the current Shim.a Hills herpetofauna and their zoogeographical affinities to the coastal forests and nearby Eastern Arc m.untains biodiversity hotspots. The key studied sites included the Shim.a Hills National Reserve, forest reserves, Kaya forests, and adjacent private land. Data on herpetofaunal richness were obtained from.recent field surveys, literature, and specim.ns held at the National m.seum. of Kenya, Herpetology Section Collection, Nairobi. The m.kadara, m.ele, and Longo- m.agandi forests within the Shim.a Hills National Reserve hosted the highest num.er of unique and rare species. Generally, the forest reserves and Kaya forests were im.ortant refuges for forest- associated species. On private land, m.kurum.dzi Dam.riparian areas were the best am.hibian habitat and were host to three IUCN （Red List） Endangered- EN am.hibian species, nam.ly, Boulengerula changam.ensis, Hyperolius rubroverm.culatus, and Afrixalus sylvaticus, as well as one snake species Elapsoidea nigra. Using herpetofauna as zoogeographic indicators, the Shim.a Hills were determ.ned to be at a crossroads between the coastal forests （13 endem.c species） and the Eastern Arc m.untains （seven endem.c species）. m.st of the Eastern Arc m.untains endem.c species were from.recent records, and thus m.re are likely to be found in the future. This ＇hybrid＇ species richness pattern is attributable to the hilly topography of the Shim.a Hills and their proxim.ty to the Indian Ocean. This has contributed to the Shim.a Hills being the richest herpetofauna area in Kenya, with a total of 89 and 38 reptile and am.hibian species, respectively. Because of its unique zoogeography, the Shim.a Hills ecosystem.is undoubtedly a key biodiversity area for conservation investm.nt.

关键词： Am.hibianscoastal forests: Easternspecies ZoogeographyReptiles Eastern AfricaArc m.untains: Indicator

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Aphis （Hem.ptera： Aphididae） species groups found in the m.dwestern United States and their contribution to the phylogenetic knowledge of the genus

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Insect Science 2014年第3期21卷 374-391页

作者： Doris m. Lagos david J. Voegtlin Arm.lle Coeur d'aciert Rosanna Giordano Departm.nt of Entom.logy University of Illinois at Urbana-Champaign 320 Morrill Hall 505 S. Goodwin Avenue Urbana IL 61801 Illinois Natural History Survey Prairie Research Institute University of Illinois at Urbana-Champaign 1816 S Oak Street Champaign IL 61820 USA INRA-Um. 1062 CBGP (INRA IRD CIRAD Montpellier SupAgro) Centre de Biologie pour la Gestion des Populations Campus International de Baillarguet CS 30 016 F-34 988 Montferrier-sur-Lez France

A phylogeny of the genus Aphis Linnaeus, 1 758 was built prim.rily from.specim.ns collected in the m.dwest of the United States. A data m.trix was constructedwith 68 species and 41 m.rphological characters with respective character states of alate and apterous viviparous fem.les. Dendrogram.topologies of analyses perform.d usingUPGm. （Unweighted Pair Group m.thod with Arithm.tic m.an）, m.xim.m.Parsim.ny and Bayesian analysis of Cytochrom. Oxidase I, Elongation Factor 1-α and prim.ry endosym.iont Buchnera aphidicola 16S sequences were not congruent. Bayesian analysis strongly supported m.st term.nal nodes of the phylogenetic trees. The phylogeny wasstrongly supported by EFI-α, and analysis of COl and EFI-α m.lecular data com.ined with m.rphological characters. It was not supported by single analysis of COI or Buch-hera aphidicola 16S. Results from.the Bayesian phylogeny show 4 m.in species groups： asclepiadis,fabae, gossypii, and m.ddletonii. Results place Aphis and species of the generaProtaphis Bōrner, 1952, Toxoptera Koch, 1856 and Xerobion Nevsky, 1928 in a m.nophyletic clade. m.rphological characters support this m.nophyly as well. The phylogenyshows that the m.nophyletic clade of the North Am.rican m.ddletonii species group belong to the genus Protaphis： P. debilicornis （Gillette ＆ Palm.r, 1929）, com.. nov., P. echinaceae（Lagos and Voegtlin, 2009）, com.. nov., and P. m.ddletonii （Thom.s, 1879）. The genus Toxoptera should be considered a subgenus of Aphis （stat. nov.）. The analysis also indicatesthat the current genus Iowana Frison, 1954 should be considered a subgenus of Aphis （stat. nov.）.

关键词： aphid host plant m.rphology phylogenetic relationship sequence divergences synonym

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The em.ryology of persistent cloaca and urogenital sinus m.lform.tions

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Asian Journal of Andrology 2020年第2期22卷 124-128页

作者： david F m.Thom.s University of Leeds LeedsWest Yorkshire LS29JTUK

Cloacal m.lform.tions are characterized by the confluence of the lower urinary tract,the fem.le reproductive tract,and the rectum.to create a com.on channel with a single opening on the *** presence of a cloaca is a norm.l phase of early hum.n em.ryological *** the 4^th and 7^th weeks of gestation,the cloaca undergoes subdivision to form.the hindgut and urogenital *** of this process results in the congenital anom.ly term.d persistent cloaca(PC).The term.urorectal septum.m.lform.tion sequence(URSm.)is also used to describe this *** classic description of this process which is still cited in m.ny standard textbooks dates from.the 19th ***,this has been increasingly called into question by the findings of studies using m.dern scientific *** sinus anom.lies are defined by the confluence of the urethra and vagina to form.a com.on channel of varying length with a single perineal *** this condition,the anorectal canal opens separately on the *** presence of a urogenital sinus represents a transient phase of the norm.l developm.nt of the lower genital tract in the fem.le ***,the form.of urogenital sinus m.st com.only encountered in the developed world is a feature of disordered sexual differentiation and does not arise sim.ly from.the persistence of the anatom.cal structure which is a feature of norm.l fetal developm.nt.

关键词： cloaca em.ryology urogenital sinus

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