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Current Zoology 2024年第5期70卷 647-658页

作者： joséMartín Gonzalo Rodríguez-Ruiz joséJavier Cuervo Departamento de Ecología Evolutiva Museo Nacional de Ciencias NaturalesCSICMadridSpain

Habitat selection is a dynamic process that depends on many environmental variables that can vary with weather *** is important because,within a context of global change,extreme weather events,such as severe droughts,are predicted to become more *** examined the patterns of microhabitat selection and underground movements(using PIT-tag telemetry)of a strictly fossorial reptile,the North African checkboard amphisbaenian Trogonophis wiegmanni,during the summer drought *** aimed to test whether changes in strategies of habitat use and movements could allow this amphisbaenian to cope with unfavorable *** found that during the summer drought period,*** did not use the microhabitats in relationship to their availability,but particularly selected sites with high abundance of rocks but also areas under a high cover of bushes,where environmental conditions were more *** also found,using PIT-tag telemetry,that the numbers of *** individuals located under rocks and their activity(number of days with movements)decreased largely in ***,the animals were not entirely inactive,but,especially males were active below the ground under bushes and made some relatively long underground hidden movements between favorable areas.

关键词： arid environments fossoriality habitat selection movement ecology Trogonophis wiegmanni weather conditions

Detecting polygenic selection in marine populations by combining population genomics and quantitative genetics approaches

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Current Zoology 2016年第6期62卷 603-616页

作者： Pierre-alexandre GAGNAIRE Oscar E. GAGGIOTTI Universite Montpellier 2 Place Eugene Bataillon 34095 Montpellier Cedex 5 France ISEM - CNRS UMR 5554 SMEL 2 rue des Chantiers Sete 34200 France Scottish Oceans Institute University of St Andrews East Sands St Andrews KY16 9LB UK

Highly fecund marine species with dispersive life-history stages often display large population sizes and wide geographic distribution ranges. Consequently, they are expected to experience reduced genetic drift, efficient selection fueled by frequent adaptive mutations, and high migration loads. This has important consequences for understanding how local adaptation proceeds in the sea. A key issue in this regard, relates to the genetic architecture underlying fitness traits. Theory predicts that adaptation may involve many genes but with a high variance in effect size. Therefore, the effect of selection on allele frequencies may be substantial for the largest effect size loci, but insignificant for small effect genes. In such a context, the performance of population genomic methods to unravel the genetic basis of adaptation depends on the fraction of adaptive genetic variance explained by the cumulative effect of outlier loci. Here, we address some methodological challenges associated with the detection of local adaptation using molecular approaches. We provide an overview of genome scan methods to detect selection, including those assuming complex demographic models that better describe spatial population structure. We then focus on quantitative genetics approaches that search for genotype-phenotype associations at different genomic scales, including genome-wide methods evaluating the cumulative effect of variants. We argue that the limited power of single locus tests can be alleviated by the use of polygenic scores to estimate the joint contribution of candidate variants to phenotypic variation.

关键词： local adaptation genome scans quantitative genetics genotype-phenotype association polygenic scores.

Carbon Dioxide/Methane Separation by Adsorption on Sepiolite

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Journal of Natural Gas Chemistry 2007年第3期16卷 235-243页

作者： josé A.Delgado María A.Uguina josé L.Sotelo Beatriz Ruíz Marcio Rosário Department of Chemical Engineering Universidad Complutense de Madrid28040Madrid.Spain

In this work, the use of sepiolite for the removal of carbon dioxide from a carbon dioxide/methane mixture by a pressure swing adsorption （PSA） process has been researched. Adsorption equilibrium and kinetics have been measured in a fixed-bed, and the adsorption equilibrium parameters of carbon dioxide and methane on sepiolite have been obtained. A model based on the LDF approximation has been employed to simulate the fixed-bed kinetics, using the Langmuir equation to describe the adsorption equilibrium isotherm. The functioning of a PSA cycle for separating carbon dioxide/methane mixtures using sepiolite as adsorbent has also been studied. The experimental results were compared with the ones predicted by the model adapted to a PSA system. Methane with purity higher than 97% can be obtained from feeds containing carbon dioxide with concentrations ranging from 34% to 56% with the proposed PSA cycle. These results suggest that sepiolite is an adsorbent with good properties for its employment in a PSA cycle for carbon dioxide removal from landfill gases.

关键词： carbon dioxide methane sepiolite adsorption fixed-bed pressure swing adsorption

Origin of light emission and enhanced Eu^(3+) photoluminescence in tin-containing glass

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Journal of Rare Earths 2015年第1期33卷 27-32页

作者： josé A.Jiménez Esteban Rosim Fachini Department of Chemistry University of North FloridaJacksonville FL 32224 USA Department of Physical Sciences General Studies Faculty University of Puerto RicoRío Piedras PR 00931 USA

A barium-phosphate glass matrix was co-doped with Sn O and Eu2O3 for investigating on material luminescent properties. Optical absorption and X-ray photoelectron spectroscopy（XPS） were employed in the characterization of tin species. The prevalence of divalent tin was indicated by the XPS data in accord with a conspicuous absorption band detected around 285 nm ascribed to twofold-coordinated Sn centers（isoelectronic with Sn^2＋）. Photoluminescence（PL） excitation spectra obtained by monitoring Eu^3＋ emission from the 5D0 state revealed a broad excitation band from about 250 to 340 nm, characteristic of donor/acceptor energy transfer. Under excitation of such at 290 nm, the co-doped material exhibited a bright whitish luminescence, and a four-fold enhanced Eu3＋ emission relative to a purely Eu-doped reference. Time-resolved PL spectra recorded under the excitation at 290 nm exposed a broad band characteristic of the twofold-coordinated Sn centers and emission bands of Eu^3＋ ions, which appeared well separated in time in accord with their emission decay dynamics. The data suggested that light absorption took place at the Sn centers（donors） followed by energy transfer to Eu^3＋ ions（acceptors） which resulted in populating the 5D0 emitting state. Energy transfer pathways likely resulting in the enhanced Eu3＋ photoluminescence and the consequential light emission were discussed.

关键词： energy transfer glasses luminescence optical materials rare earths

On the Numerical Solution of Some Eikonal Equations:An Elliptic Solver Approach

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Chinese Annals of Mathematics,Series B 2015年第5期36卷 689-702页

作者： alexandre CABOUSSAT Roland GLOWINSKI Tsorng-Whay PAN Haute Ecole de Gestion de Genève University of Applied Sciences Department of Mathematics University of Houston

The steady Eikonal equation is a prototypical first-order fully nonlinear equation. A numerical method based on elliptic solvers is presented here to solve two different kinds of steady Eikonal equations and compute solutions, which are maximal and minimal in the variational sense. The approach in this paper relies on a variational argument involving penalty, a biharmonic regularization, and an operator-splitting-based time-discretization scheme for the solution of an associated initial-value problem. This approach allows the decoupling of the nonlinearities and differential *** experiments are performed to validate this approach and investigate its convergence properties from a numerical viewpoint.

关键词： Eikonal equations Maximal solutions Regularization methods Operator slalitting Finite element methods

Flow regimes in wet conical spouted beds using glass bead mixtures

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Particuology 2008年第2期6卷 72-80页

作者： Marcelo S.Bacelos jos Teixeira Freire Universidade Federal de Sāo Carlos Centro de Ciências Exatas e de TecnologiaPrograma de Pós-Graduacāo em Engenharia QuímicaCentro de Secagem de PastasSuspensōes e SementesRod.Washington LuizKm 23513565-905CP 676Sāo CarlosSPBrazil

Using a high-viscosity Newtonian fluid, glycerol, an experimental investigation was carried out to evaluate the stable spouting regime in conical spouted beds using four particle mixtures： a reference （monoparticles）, a binary mixture, two ternary mixtures with flat and Gaussian distributions respectively. The mixtures were selected for particle diameters （dp） ranging from 1.09 to 4.98 mm and particle diameter ratios （dpL/dps） ranging from 1.98 to 4.0. Experimental data show that pressure fluctuation signals of the bed, as indicated by changes in their standard deviations, provide suitable information to identify the range of operational conditions for stable spouting. However, the analysis of skewness of curves of pressure fluctuation as a function of air velocity appears not sufficient to identify a particular flow regime. For glycerol in the spouting regime, the standard deviation is noted to increase with increasing glycerol concentration due to the growth of interparticle forces. The implications of these research findings on the drying of suspensions in conical spouted beds using glass bead mixtures are also discussed.

关键词： Conical spouted bed Binary and ternary mixtures Processing of pastes Spouting regimes Spouting stability Pressure fluctuation

Fast synthesis of gold nanoparticles by cold atmospheric pressure plasma jet in the presence of Au^(+) ions and a capping agent

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Plasma Science and Technology 2024年第7期26卷 108-115页

作者： Tatiana HABIB josé Mauricio A.CAIUT Bruno CAILLIER Laboratoire Diagnostics des Plasmas Hors Equilibre(DPHE) Universitéde ToulouseINU ChampollionAlbi 81000France Department of Chemistry The Nanomaterials and Luminescent Systems GroupFaculty of PhilosophyScience and Letters at Ribeirão PretoUniversity of São PauloRibeirão Preto-SP 14040-901Brazil

Homogeneous gold nanoparticles were synthesized under atmospheric pressure using a nonthermal helium plasma jet in a single-step process.A current power supply was used to generate the plasma discharge rich in diverse reactive *** species induce rapid chemical reactions responsible for the reduction of the gold salts upon contact with the liquid *** this study,spherical and monodispersed gold nanoparticles were obtained within 5 min of plasma exposure using a solution containing gold(Ⅲ)chloride hydrate(HAuCl_(4))as a precursor and polyvinylpyrrolidone(PVP)as a capping agent to inhibit *** formation of these metal nanoparticles was initially perceptible through a visible change in the sample's color,transitioning from light yellow to a red/pink *** was subsequently corroborated by UVvis spectroscopy,which revealed an optical absorption in the 520-550 nm range for Au NPs,corresponding to the surface plasmon resonance(SPR)*** investigation into the impact of various parameters,including plasma discharge duration,precursor and capping agent concentrations,was carried out to optimize conditions for the formation of well-separated,spherical gold *** light scattering(DLS)was used to measure the size of these nanoparticles,transmission electron microscopy(TEM)was used to observe their morphology and X-ray diffraction(XRD)was also employed to determine their crystallographic *** results confirm that homogeneous spherical gold nanoparticles with an average diameter of 13 nm can be easily synthesized through a rapid,straightforward,and environmentally friendly approach utilizing a helium atmospheric pressure plasma.

关键词： gold nanoparticles non-thermal plasma jet helium DBD

Surgical risk for patients with Chagasic achalasia and its correlation with the degree of esophageai dilation

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World Journal of Gastroenterology 2005年第37期11卷 5840-5844页

作者： josé Garcia Neto Roberto de Cleva Bruno Zilberstein Joaquim josé Gama-Rodrigues Surgery Division Hospital das Clínicas Federal University of Goiás Medical School Goiás Brazil Gastroenterology Department Digestive Tract Surgery Division Hospital das Clínicas University of Sao Paulo Medical School So Paulo Brazil

AIM： To analyze the risk of cardiovascular complications in patients with indication for surgical treatment of Chagasic esophageal achalasia and to correlate the surgical risks with the degree of esophageal dilation, thereby proposing a risk scale index. METHODS： One hundred and twenty-four patients with Chagasic esophageal achalasia, who received surgical treatment at the Hospital das Clinicas of the Federal University of Goiás, were included in this study. The patients were mostly related to the postoperative complications due to the cardiovascular system. All the patients were submitted to：（1） clinical history to define the cardiac functional class （New York Heart Association）; （2） conventional 12-lead electrocardiogram at rest; and （3） contrast imaging of the esophagus to determine esophageal dilatation according to Rezende＇s classification of Chagasic megaesophagus. RESULTS： An assessment of the functional classification （FC） of heart failure during the preoperative period determined that 67 patients （54.03%） were assigned functional class Ⅰ （FC Ⅰ）, 46 patients （37.09%） were assigned functional class Ⅱ （FC Ⅱ）, and 11 patients （8.87%） were assigned functional class Ⅲ （FC Ⅲ）. None of the patients were assigned to functional class Ⅳ （FC Ⅳ）. There was a positive correlation between the functional class and the postoperative complications （FC Ⅰ×FC Ⅱ： P〈0.001; FC Ⅰ×FC Ⅲ： P〈0.001）. The ECG was normal in 44 patients （35.48%） and presented abnormalities in 80 patients （64.52%）. There was a significant statistical correlation between abnormal ECG （arrhythmias and primary change in ventricular repolarization） and postoperative complications （P〈0.001）. With regard to the classification of the Chagasic esophageal achalasia, the following distribution was observed： group Ⅱ, 53 patients （42.74%）; group Ⅲ, 37 patients （29.83%）; and group Ⅳ, 34 patients （27.41%）. There was a positive correlation between the degree of esophageal dilation and the increase in postoperative compli

关键词： Postoperative Chagas' disease Surgical risk Chagasic achalasia Cardiovascular risk

Capsule endoscopy and panendoscopy:A journey to the future of gastrointestinal endoscopy

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World Journal of Gastroenterology 2024年第10期30卷 1270-1279页

作者： Bruno Rosa joséCotter Department of Gastroenterology Hospital da Senhora da OliveiraGuimarães 4835-044Portugal Life and Health Sciences Research Institute School of MedicineUniversity of MinhoBraga 4710-057Portugal ICVS/3B's PT Government Associate LaboratoryBraga 4710-057Portugal

In 2000,the small bowel capsule revolutionized the management of patients with small bowel ***,the technological development achieved by the new models of double-headed endoscopic capsules,as miniaturized devices to evaluate the small bowel and colon[pan-intestinal capsule endoscopy(PCE)],makes this non-invasive procedure a disruptive concept for the management of patients with digestive *** technology is expected to identify which patients will require conventional invasive endoscopic procedures(colonoscopy or balloon-assisted enteroscopy),based on the lesions detected by the capsule,i.e.,those with an indication for biopsies or endoscopic *** use of PCE in patients with inflammatory bowel diseases,namely Crohn’s disease,as well as in patients with iron deficiency anaemia and/or overt gastrointestinal(GI)bleeding,after a non-diagnostic upper endoscopy(esophagogastroduodenoscopy),enables an effective,safe and comfortable way to identify patients with relevant lesions,who should undergo subsequent invasive endoscopic *** recent development of magnetically controlled capsule endoscopy to evaluate the upper GI tract,is a further step towards the possibility of an entirely non-invasive assessment of all the segments of the digestive tract,from mouth-to-anus,meeting the expectations of the early developers of capsule endoscopy.

关键词： Non-invasive endoscopy Panendoscopy Magnetically controlled capsule endoscopy Crohn’s disease Digestive bleeding

Gut microbiota:a potential therapeutic target for Parkinson's disease

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Neural Regeneration Research 2021年第2期16卷 287-288页

作者： joséFidel Baizabal-Carvallo Department of Science and Engineering University of GuanajuatoGuanajuatoMéxico

Parkinson's disease(PD)is a neurodegenerative disorder characterized by accumulation ofα-synuclein in neurons of the central nervous system(CNS).The pathogenesis of PD is complex and only partially *** evidence pointed to the basal ganglia as the source of the motor manifestations of PD,and likely the origin of the pathological *** the last two decades。

关键词： process. therapeutic pathogenesis