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The flowerpiercers interactions with a community of high Andean plants

Avian Research 2021年第2期12卷 181-194页

作者： Jairo Andrés cuta-Pineda Luis alejandro Arias-Sosa Roxibell c.Pelayo Research Group“Grupo Ecología de Organismos(GEO-UPTc)” TunjaColom-bia Maestría en ciencia Biológicas Universidad Pedagógica y Tecnológica de ColombiaTunjaColombia Instituto de ciencias Ambientales y Ecológicas(IcAE) Universidad de Los AndesMéridaVenezuela

Background:Flowerpiercers(Diglossa)are traditionally considered as“parasites”of the pollination processes,as they can access the nectar without entering in contact with the reproductive structures of the ***,the effect of flowerpiercers seems to vary according to their behavior and the flower’s ***,in this work,we aimed to explore the floral characteristics that may determine the susceptibility to robbing and pollen transport by ***,we identified the potential types of interactions and studied interaction network ***:We collected the information of 16 ornithophilic plants regarding their floral traits and robbing ***,we captured 4 species of flowerpiercers and evaluated pollen transport(frequency and loads).We tested the correlation between floral traits,robbing frequency,and pollen ***,we used these variables in a cluster and principal component analyses to identify the potential types of ***,we analyzed and com-pared the structure of the plants-flowerpiercers interaction ***:Nectar production significantly influenced both nectar robbing and pollen *** the corolla length was only correlated to the robbing ***,we found that particular flowerpiercers species trans-ported higher loads of some plant pollen,which can be related to the differences in behavior and morphometric *** proposed the classification of five different types of plant-flowerpiercer interactions,that showed differ-ent potential mutualist or antagonist relations based on the affectation of nectar robbing and the service of pollen *** interaction networks consisted of 49 links,with 2.4 links per species,and presented indicators of a medium to high resilience,stability,and resistance(nestedness,connectance,and robustness).Also,the network presented medium to low specialization and substantial niche ***:The ecological role of

关键词： Diglossa Flower traits Nectar robbing Nectivorous birds Pollen transport Pollination

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Selectivity in feeding preferences and ranging patterns in spider monkeys Ateles geoffroyi yucatanensis of northeastern Yucatan peninsula, Mexico

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current Zoology 2013年第1期59卷 125-134页

作者： carmen ScHERBAUM alejandro ESTRADA Department of Animal Ecology and Tropical Biology Biozentrum University of Wiirzburg Germany Estacion de Biologia Tropical Los Tuxtlas Instituto de Biologfa Universidad Nacional Aut6noma de M6xico Apartado Postal94 San Andres Tuxtla Veracruz M6xico C. P. 95700

The spider monkey, a fruit specialist and important seed dispersal agent in the Neotropics, is an endangered primate due to habitat loss, hunting and the pet trade. Spider monkeys have been the subject of a few studies in central and South Ame- rica, but little is known about the diet and ranging for this primate in southern Mexico. Here we report the results of a six-month long study （October 2010 to March 2011） of the feeding preferences and ranging patterns of the Yucatan spider monkey Ateles geoffroyi yucatanensis living in the ＂Ya＇ax＇che＂ reserve by the caribbean coast in northeast Yucatan peninsula. Focal animal and scan sampling as well as GPS tracking were used to document spider monkey feeding behavior, location of food trees and ranging in the reserve. The spider monkeys used 36 species of plants （94% trees; n = 432） and six non tree morphospecies as a source of food. Six tree species accounted for 〉~80% of total feeding time and for 74% of all trees used. Fruits accounted for 59% of total feeding time, followed by leaves （35%）, palm piths （5%） and other plant parts （1%）. Total range used by the monkeys was esti- mated at 43% of semievergreen rainforest habitat available （ca 40ha）. Range use was not random with segments showing light, moderate and heavy use; the use of different areas of their range varied monthly and was closely linked to the spatial dispersion of the trees used for food [current Zoology 59 （1）： 125-134, 2013].

关键词： Primates Frugivory Neotropics conservation Seed dispersal

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current concepts in the management of the duplicated thumb

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Plastic and Aesthetic Research 2023年第1期10卷 137-146页

作者： Tanir Moreno alejandro Gimenez William c.Pederson Division of Plastic Surgery Baylor College of MedicineHoustonTX 77030USA

Preaxial polydactyly is a common congenital anomaly of the hand presenting at *** treatment is aimed at creating a functional thumb capable of normal grip and pinch strength with acceptable *** case is unique and presents individual challenges to the hand *** aim of this review is to provide a synopsis of current knowledge and recommended surgical techniques for the duplicated thumb.

关键词： Preaxial polydactyly hand deformities reconstructive surgical procedures thumb duplication congenital anomaly

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Semantic Segmentation of Sorghum Using Hyperspectral Data Identifies Genetic Associations

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Plant Phenomics 2020年第1期2卷 14-24页

作者： chenyong Miao alejandro Pages Zheng Xu Eric Rodene Jinliang Yang James c.Schnable center for Plant Science Innovation University of Nebraska-LincolnLincolnNEUSA Department of Agronomy and Horticulture University of Nebraska-LincolnLincolnNEUSA Quantitative Life Sciences Initiative University of Nebraska-LincolnLincolnNEUSA Department of Mathematics and Statistics Wright State UniversityDaytonOHUSA

This study describes the evaluation of a range of approaches to semantic segmentation of hyperspectral images of sorghum plants,classifying each pixel as either nonplant or belonging to one of the three organ types(leaf,stalk,panicle).While many current methods for segmentation focus on separating plant pixels from background,organ-specific segmentation makes it feasible to measure a wider range of plant *** scored training data for a set of hyperspectral images collected from a sorghum association population was used to train and evaluate a set of supervised classification *** algorithms show acceptable accuracy for this classification *** trained on sorghum data are able to accurately classify maize leaves and stalks,but fail to accurately classify maize reproductive organs which are not directly equivalent to sorghum *** measurements extracted from semantic segmentation of sorghum organs can be used to identify both genes known to be controlling variation in a previously measured phenotypes(e.g.,panicle size and plant height)as well as identify signals for genes controlling traits not previously quantified in this population(e.g.,stalk/leaf ratio).Organ level semantic segmentation provides opportunities to identify genes controlling variation in a wide range of morphological phenotypes in sorghum,maize,and other related grain crops.

关键词： Sorghum classify organs

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Overexpression of an ABA biosynthesis gene using a stress-inducible promoter enhances drought resistance in petunia

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Horticulture Research 2015年第1期2卷 255-263页

作者： alejandro c Estrada-Melo chao Ma Michael S Reid cai-Zhong Jiang Department of Plant Sciences University of California DavisDavisCAUSA United States Department of Agriculture Crops Pathology and Genetic Research UnitAgricultural Research ServiceDavisCAUSA

The response of plants to drought stress includes reduced transpiration as stomates close in response to increased abscisic acid(ABA)*** overexpression of 9-cis-epoxycarotenoid dioxygenase(NcED),a key enzyme in ABA biosynthesis,increases drought resistance,but causes negative pleiotropic effects on plant growth and *** overexpressed the tomato NcED(LeNcED1)in petunia plants under the control of a stress-inducible promoter,*** water stress,the transgenic plants had increased transcripts of NcED mRNA,elevated leaf ABA concentrations,increased concentrations of proline,and a significant increase in drought *** transgenic plants also displayed the expected decreases in stomatal conductance,transpiration,and *** 14 days without water,the control plants were dead,but the transgenic plants,though wilted,recovered fully when ***-watered transgenic plants grew like non-transformed control plants and there was no effect of the transgene on seed dormancy.

关键词： inducible pet drought

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Spin-resolved self-doping tunes the intrinsic halfmetallicity of AIN nanoribbons

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Nano Research 2014年第1期7卷 63-70页

作者： alejandro Lopez-Bezanilla P. Ganesh Paul R. c. Kent Bobby G. Sumpter Oak Ridge National Laboratory One Bethel Valley Road Oak Ridge Tennessee 37831-6493 USA Present address: Argonne National Laboratory 9700 South Cass Avenue Lemont IL 60439 USA

We present a first-principles theoretical study of electric field- and straincontrolled intrinsic half-metallic properties of zigzagged aluminium nitride （A1N） nanoribbons. We show that the half-metallic property of AIN ribbons can undergo a transition into fully-metallic or semiconducting behavior with application of an electric field or uniaxial strain. An external transverse electric field induces a full charge screening that renders the material semiconducting. In contrast, as uniaxial strain varies from compressive to tensile, a spin-resolved selective self-doping increases the half-metallic character of the ribbons. The relevant strain-induced changes in electronic properties arise from band structure modifications at the Fermi level as a consequence of a spin-polarized charge transfer between p-orbitals of the N and A1 edge atoms in a spin-resolved self-doping process. This band structure tunability indicates the possibility of designing magnetic nanoribbons with tunable electronic structure by deriving edge states from elements with sufficiently different localization properties. Finite temperature molecular dynamics reveal a thermally stable half-metallic nanoribbon up to room temperature.

关键词： aluminum nitride half-metallicity strain electric field

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Silver sulfide leaching with a copper-thiosulfate solution in the absence of ammonia

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Rare Metals 2011年第2期30卷 105-109页

作者： cUI Yiqi TONG Xiong alejandro Lopez-Valdivieso Faculty of land and Resource Engineering Kunming University of Science and Technology Kunming 650093 China Instituto de Metalurgia UniversidadAutonoma de San Luis Potosi San Luis Potosi C.P. 78210 Mexico

Leaching from silver *** a copper-thiosulfate solution in the absence of ammonia was investigated. It is found that silver sulfide could be effectively dissolved in the copper-thiosulfate system without ammonia. The effects of thiosulfate concentration, cop- per-to-thiosulfate ratio, agitation vigorousness, pH values, and dissolved gases on the leaching of silver sulfide with the copper-thiosulfate solution were studied. A maximum extraction of 95.1% was achieved with the 0.12 mol/L thiosulfate and the 0.048 rnol/L copper sulfate. It is shown that copper-to-thiosulfate ratio is an important factor in silver sulfide dissolution and oxygen is not needed to leach silver sulfide, which leads to the instability of the leaching system at high copper-to-thiosulfate ratio. On the other hand, the silver extraction is not affected by the pulp pH values.

关键词： extraction silver leaching copper sulfate thiosulfate

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Gastrointestinal disorders associated with migraine: A comprehensive review

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World Journal of Gastroenterology 2016年第36期22卷 8149-8160页

作者： carlos R cámara-Lemarroy Rene Rodriguez-Gutierrez Roberto Monreal-Robles alejandro Marfil-Rivera Servicio de Neurología Hospital Universitario "Dr. José E. González" Universidad Autónoma de Nuevo León Servicio de Endocrinología Hospital Universitario "Dr. José E. González" Universidad Autónoma de Nuevo León Servicio de Gastroenterología Hospital Universitario "Dr. José E. González" Universidad Autónoma de Nuevo León

Migraine is a recurrent and commonly disabling primary headache disorder that affects over 17% of women and 5%-8% of men. Migraine susceptibility is multifactorial with genetic, hormonal and environmental factors all playing an important role. The physiopathology of migraine is complex and still not fully understood. Many different neuropeptides, neurotransmitters and brain pathways have been implicated. In connection with the myriad mechanisms and pathways implicated in migraine, a variety of multisystemic comorbidities(e.g., cardiovascular, psychiatric and other neurological conditions) have been found to be closely associated with migraine. Recent reports demonstrate an increased frequency of gastrointestinal(GI) disorders in patients with migraine compared with the general population. Helicobacter pylori infection, irritable bowel syndrome, gastroparesis, hepatobiliary disorders, celiac disease and alterations in the microbiota have been linked to the occurrence of migraine. Several mechanisms involving the gut-brain axis, such as a chronic inflammatory response with inflammatory and vasoactive mediators passing to the circulatory system, intestinal microbiota modulation of the enteric immunological milieu and dysfunction of the autonomic and enteric nervous system, have been postulated to explain these associations. However, the precise mechanisms and pathways related to the gut-brain axis in migraine need to be fully elucidated. In this review, we survey the available literature linking migraine with GI disorders. We discuss the possible physiopathological mechanisms, and clinical implications as well as several future areas of interest for research.

关键词： Migraine Headache Microbiota Review Gastrointestinal diseases

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Highlights of ASS234: a novel and promising therapeutic agent for Alzheimer’s disease therapy

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Neural Regeneration Research 2020年第1期15卷 30-35页

作者： alejandro Romero JoséMarco-contelles Eva Ramos Department of Pharmacology&Toxicology Faculty of Veterinary MedicineComplutense University of MadridMadridSpain Laboratory of Medicinal chemistry Institute of General Organic Chemistry(CSIC)MadridSpain

There is no effective treatment to face Alzheimer’s disease *** molecules are a good approach against the multiple physiopathological events associated with its development and *** this context,N-((5-(3-(1-benzylpiperidin-4-yl)propoxy)-1-methyl-1H-indol-2-yl)methyl)-N-methylprop-2-yn-1-amine(ASS234)has been tested achieving promising ***234 has demonstrated to cross the blood-brain barrier in vivo,and a good in silico safety profile being less toxic than ***,ASS234 reversibly inhibits human acetyl-and butyryl-cholinesterase,and irreversibly inhibits human monoamine oxidase A and ***,this multitarget molecule has antioxidant and neuroprotective properties,and inhibitsΑβ1–42 andΑβ1–40 *** about the mechanism of action,several signaling pathways related to Alzheimer’s disease had been explored showing that ASS234 induces the wingless-type MMTV integration site(Wnt)family and several members of the heat shock proteins family and moreover counteracts neuroinflammatory and oxidative stress-related genes promoting the induction of several key antioxidant ***,in vivo experiments with ASS234 in c57BL/6J mice displayed its ability to reduce amyloid plaque burden and gliosis in the cortex and hippocampus,ameliorating scopolamine-induced learning *** we gather the information regarding ASS234 evaluated so far,showing its ability to face different targets,necessary to counteract a neurodegenerative disease as complex as the Alzheimer’s disease.

关键词： AchE BuchE gene expression heat shock proteins inflammation in silico toxicology MAO A/B neuroprotection oxidative stress Wnt signaling

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Inconsistencies in four-dimensional Einstein-Gauss-Bonnet gravity

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chinese Physics c 2021年第1期45卷 89-96页

作者： Julio Arrechea Adria Delhom alejandro Jimenez-cano Instituto de Astrofisica de Andalucia(IAA-cSIc) Glorieta de la AstronomiaGranadaSpain Departamento de Fisica Teorica and IFIc Centro Mixto Universidad de Valencia-CSIC.Universidad de ValenciaBuijassot-46100ValenciaSpain Departamento de Fisica Teorica y del cosmos and cAFPE Universidad de Granada18071 GranadaSpain

We attempt to clarify several aspects concemi ng the recently presented four-dimensional Ein stein-Gauss-Bonnet *** argue that the limiting procedure outlined in[***.124,081301(2020)]generally involves ill-defined terms in the four dimensional field *** ways to circumvent this issue are discussed,alongside remarks regarding specific solutions of the *** prove that,although linear perturbations are well behaved around maximally symmetric backgrounds,the equations for second-order perturbations are illdefined even around a Minkowskia n *** on ally,we perform a detailed analysis of the spherically symmetric solutions and find that the central curvature singularity can be reached within a finite proper time.

关键词： alternative theories of gravity singularities Einstein・Gauss-Bonnet

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