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Occurrence data m.y provide unreliable therm.l preferences and breadth of species

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Current Zoology 2015年第6期61卷 972-982页

作者： Sara VILLEN-perez Luis m. CARRASCAL Departm.nt of Biogeography and Global Change National Museum of Natural Sciences MNCN-CSIC. C/José Gutiérrez Abascal 2 28006 Madrid Spain.

Accurate inform.tion on the therm.l preference and specialization of species is needed to understand and predict spe- cies geographical range size and vulnerability to clim.te change. Here we estim.te the position and breadth of species within therm.l gradients based on the shape of the response curve of species abundance to tem.erature. The objective of the study is to com.are the m.asurem.nts of this approach based on abundance data with those of the classical approach using species＇ occur- rence data. The relationship between species＇ relative abundance and m.nim.m.winter tem.erature of 106 bird species wintering in the Iberian Peninsula is m.deled at 100 Km. resolution with quadratic logistic regressions. From.these m.dels we calculated the preferred tem.erature of species as the tem.erature at which the abundance is m.xim.zed, and the therm.l breadth of species as the relative area under the tem.erature-abundance curve. We also estim.ted the therm.l preferences and breadth of species as the average tem.erature and tem.erature range of the UTm.cells in which the species are present. The abundance-tem.erature response curves reveal that birds prefer higher tem.eratures to overwinter, and are m.re therm.lly selective, than is m.asured by the classical approach. m.reover, response curves detect a higher inter-specific variability in both therm.l preferences and ther- m.l breadth of species. As occurrence data gives the sam. weight to cells with one or m.ny individuals, the average tem.erature of the cells in which the species is present roughly reflects the average tem.erature in the region of study and not the environ- m.ntal preferences of species .

关键词： Abundance-tem.erature response curve Birds Species occurrence Therm.l breadth Therm.l preferences Winter

Woodland m.diterranean birds can resist a dry extrem. cold wave

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Current Zoology 2014年第4期60卷 429-437页

作者： Sara VILLEN-perez Luis m. CARRASCAL Departm.nt of Biogeography and Global Change Museo Nacional de Ciencias Naturales (CSIC) C/Jos6 Guti6rrez Abascal 228006 Madrid Spain

The ecological consequences of clim.te extrem. events are still poorly understood, especially those related to cold episodes. Winter cold spells m.ght im.eril the energy balance of sm.ll passerines, thus com.rom.sing their survivorship. Here we analyze how the abundance and habitat use of three tree-gleaning passerine species wintering in a m.ntane oakwood of central Spain at ca. 1,300 m.a.s.1, was influenced by the cold wave that hit Europe in February 2012. We m.nitored tem.erature, wind and the relative abundance of great tit Parus m.jor, blue tit Cyanistes caeruleus and long-tailed tit Aegithalos caudatus in 15 plots throughout three periods： before, during and after the cold wave. Our results clearly rule out widespread m.rtality and tem.oral m.gration of the studied passerine populations, as the abundance of these species did not dim.nish during the cold wave. m.reover, the species usually foraging higher in the tree canopy -and thus m.re exposed to windm.ved to the less windy woodland plots （long-tailed tit） and reduced their foraging height above ground during the cold wave （long-tailed tit and blue tit）, probably to m.tigate the deleterious effects of wind chill. Therefore, these forest birds were able to cope with a dry cold wave that was statistically extrem. in term. of tem.erature and wind chill, according to the historic clim.te records of the region. It seem. that, at least when foraging substrates are not heavily covered by snow or ice, m.diterranean birds can resist an extrem. cold wave [Current Zoology 60 （4）： 429-437, 2014].

关键词： Cold wave Harsh weather m.diterranean oakwoods Tem.erature Tree-gleaning birds Wind chill

Sim.lified three-dim.nsional culture system.for long-term.expansion of em.ryonic stem.cells

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World Journal of Stem.Cells 2015年第7期7卷 1064-1077页

作者： christina m.Kee m.ck perez-Cruet Ferm.n Chavez G Rasul Chaudhry OU-WB Institute for Stem.Cell and Regenerative m.dicine Oakland University Departm.nt of Biological Sciences Oakland University Beaum.nt Health System Royal Oak Departm.nt of Chem.stry Oakland University

AIm. To devise a sim.lified and efficient m.thod for long-term.culture and m.intenance of em.ryonic stem.cells requiring less frequent passaging. m.THODS: m.use em.ryonic stem.cells(ESCs) labeled with enhanced yellow fluorescent protein were cultured in three-dim.nsional(3-D) self-assem.ling scaffolds and com.ared with traditional two-dim.ntional(2-D) culture techniques requiring m.use em.ryonic fibroblast feeder layers or leukem.a inhibitory factor. 3-D scaffolds encapsulating ESCs were prepared by m.xing ESCs with polyethylene glycol tetra-acrylate(PEG-4-Acr) and thiolfunctionalized dextran(Dex-SH). Distribution of ESCs in 3-D was m.nitored by confocal m.croscopy. Viability and proliferation of encapsulated cells during long-term.culture were determ.ned by propidium.iodide as well as direct cell counts and PrestoB lue(PB) assays. Genetic expression of pluripotency m.rkers(Oct4, Nanog, Klf4, and Sox2) in ESCs grown under 2-D and 3-D cultureconditions was exam.ned by quantitative real-tim. polym.rase chain reaction. Protein expression of selected stem.ess m.rkers was determ.ned by two different m.thods, im.unofluorescence staining(Oct4 and Nanog) and western blot analysis(Oct4, Nanog, and Klf4). Pluripotency of 3-D scaffold grown ESCs was analyzed by in vivo teratom. assay and in vitro differentiation via em.ryoid bodies into cells of all three germ.layers. RESULTS: Self-assem.ling scaffolds encapsulating ESCs for 3-D culture without the loss of cell viability were prepared by m.xing PEG-4-Acr and Dex-SH(1:1 v/v) to a final concentration of 5%(w/v). Scaffold integrity was dependent on the degree of thiol substitution of Dex-SH and cell concentration. Scaffolds prepared using Dex-SH with 7.5% and 33% thiol substitution and incubated in culture m.dium.m.intained their integrity for 11 and 13 d without cells and 22 ± 5 d and 37 ± 5 d with cells, respectively. ESCs form.d com.act colonies, which progressively increased in size over tim. due to cell proliferation as dete

关键词： Three-dim.nsional culture Pluripotency Em.ryonic s

Dynam.cs of populations with two sexes

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International Journal of Biom.them.tics 2015年第4期8卷 127-144页

作者： m. Cecilia perez E. Adriana Saavedra m.riano A. Ferrari Facultad de Ingenieria Universidad Nacional de la Patagonia San Juan Bosco Esquel Chubut Argentina Facultad de Ingenieria Universidad Nacional de la Patagonia San Juan Bosco Trelew Chubut Argentina Facultad de Ingenierla Universidad Nacional de la Patagonia San Juan Bosco Puerto Madryn Chubut Argentina Centro Nacional Patagdnico CONICET Puerto Madryn Chubut Argentina

A m.them.tical m.del is presented in order to describe the dynam.cs of polygam.us populations, bearing in m.nd single individuals of both sexes and the developm.nt of reproductive groups. In this context, the description leads us to consider positive hom.geneous dynam.cal system., establishing conditions for the stationary state existence and its local stability. A fourth pre-reproductive stage was considered, i.e. m.les and fem.les spend part of their lives before being in condition to reproduce, as a first step to consider m.re general m.dels. Finally, we param.trized the proposed m.del using southern elephant seal data, to analyze the direct applicability to a real population.

关键词： Dynam.cal system. two-sex m.del m.ting system local stability.

Use of pCONUS HPC for the treatm.nt of unruptured wide- necked bifurcation aneurysm.: early clinical experience using single antiplatelet therapy

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Stroke & Vascular Neurology 2021年第1期6卷 57-64页

作者： m.rta Aguilar perez Victoria Hellstern Carm.n Serna Candel christina Wendl Hansjorg Bazner Oliver Gansladt Hans Henkes Neuroradiologische Klinik NeurozentrumKlinikum StuttgartStuttgartGermany Institut fur Rontgendiagnostik Zentrum fur NeuroradiologieFakultat für Medizin der Universitat RegensburgRegensburgGermany Neurologische Klinik NeurozentrumKlinikum StuttgartStuttgartGermany Neurochirurgische NeurozentrumKlinikum StuttgartStuttgartGermany m.dizinische Fakultat Universitat Duisburg-EssenEssenGermany

Background In recent years,a growing num.er of stents and stent-like devices have becom. available to facilitate the treatm.nt of challenging ***,the need for dual antiplatelet therapy can lim.t their use,especially in ruptured *** hydrophilic polym.r coating(pHPC,phenox)is a novel glycan-based m.ltilayer polym.r that reduces platelet *** study aim. to report our initial experience using the pCONUS HPC device for the treatm.nt of unruptured wide-necked bifurcation aneurysm.(WNBA)using acetylsalicylic acid(ASA)as single antiplatelet therapy(SAPT).m.thods We retrospectively identified all patients who were treated with the pCONUS HPC for unruptured WNBA in a m.lti-staged procedure using ASA as *** were m.de of periprocedural com.lications,clinical outcom. and angiographic and clinical *** We identified 15 patients with 15 *** average age was 69 years old(range,41-76).Seven aneurysm. were located in the m.ddle cerebral artery,five in the anterior com.unicating artery,two at the basilar tip and one in the posterior com.unicating *** post-treatm.nt angiography showed five aneurysm. with m.dified Raym.nd-Roy classification(m.RC)grade Ⅰ and four aneurysm. with m.RC grade Ⅱ.There were no haem.rrhagic *** patients developed throm.us form.tion during the second treatm.nt session,all of them.com.letely resolving after adm.nistration of glycoprotein Ⅱb/Ⅲa *** follow-up data were available for 10 patients and showed adequate occlusion(m.RC Ⅰ or Ⅱ)in eight aneurysm.(80%).In-stent stenosis was observed in one patient whereas two patients showed de novo stenosis in one of the efferent *** This early experience on the use of the pCONUS HPC device suggests that it can be useful for treating unruptured WNBA under ASA as *** investigation with a random.sed treatm.nt registry and larger cohort is needed.

关键词： treatm.nt bifurcation HPC

Probing shock geom.try via the charge to m.ss ratio dependence of heavy ion spectra from.m.ltiple spacecraft observations of the 2013 Novem.er 4 event

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Research in Astronom. and Astrophysics 2016年第12期16卷 101-106页

作者： Lulu Zhao Gang Li Glenn m. m.son christina Cohen Richard m.waldt m.hir Desai Rob Ebert m.her Al-Dayeh Departm.nt of Physics and Space Sciences Florida Institute of Technology FL 32901 USA Departm.nt of Space Science and CSPAR University of Alabama in Hun-tsville Huntsville Alabama 35801 USA Applied Physics Laboratory Johns Hopkins University Laurel MD 20723 USA California Institute of Technology Pasadena CA 91125 USA Southwest Research Institute San Antonio TX 78228 USA University of Texas at San Antonio San Antonio TX 78249 USA

In large Solar Energetic Particle （SEP） events, ions can be accelerated at coronal m.ss ejection （Cm.）-driven shocks to very high energies. The spectra of heavy ions in m.ny large SEP events show features such as roll-overs or spectral breaks. In som. events when the spectra are plotted in term. of energy/nucleon, they can be shifted relative to each other to m.ke the spectral breaks align. The am.unt of shift is charge to m.ss ratio （Q/A） dependent and varies from.event to event. This can be understood if the spectra of heavy ions are organized by the diffusion coefficients （Cohen et al. 2005）. In the work of Li et al. （2009）, the Q/A dependence of the scaling is related to shock geom.try when the Cm.-driven shock is close to the Sun. For events where m.ltiple in-situ spacecraft observations exist, one m.y expect that different spacecraft are connected to different portions of the Cm.-driven shock that have different shock geom.tries, therefore yielding different Q/A dependence. In this work, we exam.ne one SEP event which occurred on 2013 Novem.er 4. We study the Q/A dependence of the energy scaling for heavy ion spectra using helium. oxygen and iron ions. Observations from.STEREO-A, STEREO-B and ACE are exam.ned. We find that the scalings are different for different spacecraft. We suggest that this is because ACE, STEREO- A and STEREO-B are connected to different parts of the shock that have different shock geom.tries. Our analysis indicates that studying the Q/A scaling of in-situ particle spectra can serve as a powerful tool to rem.tely exam.ne the shock geom.try for large SEP events.

关键词： Sun: particle em.ssion -- acceleration of particles

Pentacene-based nanorods on Au（111） single crystals： Charge transfer, diffusion, and step-edge barriers

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Nano Research 2013年第6期6卷 449-459页

作者： Sabine-Antonia Savu Sabine Abb Sim.n Schundelm.ier Jonathan D. Saathoff Jam.s m. Stevenson christina Tonshoff Holger F. Bettinger Paulette Clancy m. Benedetta Casu Thom.s Chasse Institute of Physical and Theoretical Chem.stry University of Tuebingen Aufder Morgenstelle 18 72076 Tuebingen Germany School of Chem.cal and Biom.lecular Engineering Cornel/University Ithaca New York 14853 USA Institute of Organic Chem.stry University of Tuebingen Auf der Morgenstelle 18 72076 Tuebingen Germany

We investigate nanorod assem.lies of two 64-substituted pentacenes, nam.ly （2,3-X2-9,10-Y2）-substituted pentacenes with X -- Y = OCH3 （m.P） and with X = F, Y-- OCH3 （m.PF）, grown on Au（111） single crystals. By using a m.lti-technique approach based on ultraviolet photoelectron spectroscopy X-ray photoelectron spectroscopy; and X-ray absorption, we find evidence for charge transfer screening at the interface with gold. Furtherm.re, the m.P and m.PF nanorods show a rough surface m.rphology, which was investigated with atom.c force m.croscopy. We use m.lecular sim.lation techniques to investigate the energetic barriers to diffusion and to traverse step-edges to estim.te their influence on the nanorod roughness. We find that barriers to surface diffusion on a terrace are anisotropic and that their direction favors the form.tion of nanorods in these m.terials.

关键词： nanorod assem.ly substituted pentacene electronic structures/ processes/m.chanism. organic electronics charge transfer diffusion and step-edge barrier

Optim.zation of High-Perform.nce Liquid Chrom.tography Param.ters for Purification of Oligonucleotide-A

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Am.rican Journal of Analytical Chem.stry 2022年第2期13卷 39-50页

作者： christina perez m.been Rani Tuan Phan Departm.nt of Chem.stry Texas Southern University Houston USA

The m.dification of high-perform.nce liquid chrom.tography param.ters leads to a m.re effective oligonucleotide-A purification process. Using various experim.ntal param.ters such as buffer, concentration, and pH, a m.thod for optim.zing the purification of an oligonucleotide-A on a reverse-phase C18 colum. was created. To purify oligonucleotide-A, High-Perform.nce Liquid Chrom.tography (HPLC), Ultraviolet-Visible Spectrophotom.try (UV-Vis), Liquid Chrom.tography-m.ss Spectrom.try (LC-m.), and lyophilization were used. Chrom.tographic data were collected with a sem.-prep HPLC system. quantified with the UV-Vis technique, and validated with the LC-m. m.thod. The m.st optim.zed param.ters found to obtain the purity of 93.0% are 40 m. triethylam.onium.bicarbonate (TEAB) buffer with pH 7, which is approxim.tely 6.0% higher than the reported m.thod of which the purity is 87.0%. However, the yield under these conditions was reduced by about 5%. The worst possible optim.zed settings that resulted in the lowest purity (84.0%) and yield (69.0%) are 10 m. am.onium.acetate (NH4CH3CO2) with pH 7.

关键词： Purification High-Perform.nce Liquid Chrom.tography Oligonucleotide-A Dipotassium.Phosphate Triethylam.onium.Acetate Triethylam.onium.Bicarbonate Am.onium.Acetate

Changes in free am.no acids and polyam.ne levels in Satsum. leaves in response to Asian citrus psyllid infestation and water stress

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Insect Science 2014年第6期21卷 707-716页

作者： Nasir S. A. m.lik Jose L. perez m.dhurababu Kunta Joseph m. Patt Robert L. m.ngan USDA-ARS ERRC 600 E Mermaid lane Wyndmoor PA 19038-8598 USDA-ARS SPARC 2881 F&B Road College Station TX 77845 Texas A&m.University-Kingsville Citrus Center 312 North International Blvd Weslaeo TX 78596 U. S. Horticultural Research Laboratory 2001 South Rock Road Fort Pierce FL 34945 Subtropical Horticultural Research Station 13601 Old Coulter Road Miami FL 33158 USDA-ARS 2413 E. Hwy 83 Weslaco TX 78596 USA

The effects of biotic and abiotic stresses on changes in am.no acids and polyam.ne levels in Satsum. orange （Citrus unshiu; cultivar Owari） leaves were inves- tigated. Asian citrus psyllids Diaphorina citri （Kuwayam.）（ACP） infestation was used to induce biotic stress while a water deficit was im.osed to induce abiotic stress. Potted trees were infested by placing 50 psyllids on 3 citrus leaves enclosed in nylon m.sh bags for 5 d. A parallel set of plants were kept water stressed by m.intaining the soil at 20% water holding capacity for 5 d. Levels of total free am.no acids were higher in water stressed and ACP infested leaves. Polyam.ne putrescine increased in infested leaves but not in water stressed leaves. Proline was the m.st abundant am.no acid and its levels significantly increased by both biotic and abiotic stresses. Proline levels in infested leaves were significantly higher than the water stressed leaves. Histidine, m.thionine, asparagine, arginine, serine, and leucine levels also increased significantly in infested leaves, but in water stressed leaves only leucine, m.thionine, and threonine increased. Levels of am.no acids, such as tyrosine, isoleucine, phenylalanine, glutam.c acid, and alanine, declined in infested leaves. Under water stress asparagine, phenylalanine, serine, and histidine also declined com.ared to controls. This indicates that while proteolysis occurred under both stresses, m.tabolic conversion of am.no acids was different under the two stresses. In ACP infested leaves som. am.no acids m.y be used as feeding m.terial and/or converted into secondary m.tabolites for defense.

关键词： am.no acids citrus Diaphorina citri polyam.nes