检索结果-南通市图书馆

Altitudinal seasonality as a potential driver of morphological diversification in rear-edge bird populations

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Avian Research 2022年第3期13卷 267-274页

作者： José Luis Tellería Irene hernández-Tellez Iván de la Hera José Ignacio Aguirre Alejandro Onrubia Department of Biodiversity Ecology and EvolutionUniversidad Complutense28040MadridSpain Department of Integrative Biology Oklahoma State UniversityStillwaterOKUSA fundaci on Migres Tarifa11380CadizSpain

Populations at the low latitude limits of a species range(rear-edge populations)are often considered more vulnerable to climate ***,their ability to track different environmental settings at a regional scale has been widely overlooked,although this may be relevant to accurately assess their adaptive capacity to cope with ongoing *** we tested whether the endemic African Chaffinch(fringilla coelebs africana)tracks environmental changes(*** temperatures,snow cover)by rearranging their numbers between seasons(spring ***)along the altitude gradients of its northwestern African *** additionally tested whether these seasonal changes in abundance were paralleled by morphological variation,suggesting a process of population *** assessed African Chaffinch abundance in tree covered farmland and woodland sites distributed along an altitude gradient in spring and *** addition,we captured and measured chaffinches within the study gradient to explore the patterns of morphological *** results showed that chaffinches shifted to lowlands from snow covered highlands during *** addition,highland individuals showed longer and more concave wings than their lowland *** morphological traits are usually related to flight efficiency in migratory birds,which suggest the presence of altitudinal movements aimed to track the environmental seasonality caused by *** results suggest a potential role of altitudinal seasonality as a driver of regional diversification within the African Chaffinch populations,which could be occurring in other North African avian species given their relatively high endemicity in the *** evolutionary and conservation implications of these displacements have been often overlooked despite they can shape the adaptive capacity of rear-edge bird populations to face the ongoing environmental changes in this peripheral area of the Palearctic.

关键词： Altitudinal movements flight apparatus Population diversification Snow cover effects

Pronuclear formation by ICSI using chemically activated ovine oocytes and zona pellucida bound sperm

在线全文

学校读者我要写书评

暂无评论

Journal of Animal Science and Biotechnology 2017年第2期8卷 370-377页

作者： J.E.hernández-Pichardo Y.Ducolomb S.Romo M.E.Kjelland R.fierro f.Casillas M.Betancourt División de Ciencias Biológicas y de la Salud Departamento de Producción Agrícola y AnimalUniversidad Autónoma Metropolitana-XochimilcoCiudad de MexicoMexico Division de Ciencias Biologicas y de la Salud Departamento de Ciencias de la SaludUniversidad Autónoma Metropolitana-IztapalapaSan Rafael Atlixco 186CP 09340 Ciudad de MexicoMexico Departamento de Ciencias Pecuarias Facultad de EstudiosSuperiores CuautitlanUNAMCiudad de MexicoEstado de MexicoMexico Conservation Genetics&BiotechLLCValley CityNDUSA Division de Ciencias Biologicas y de la Salud Departamento de Biologia de la ReproduccionUniversidad Autonoma Metropolitana-lztapalapaCiudad de MexicoMexico Doctorado en Biologia Experimental Universidad Autonoma Metropolitana-lztapalapaCiudad de MexicoMexico

Background： In order to improve ICSI, appropiate sperm selection and oocyte activation is necessary. The objective of the present study was to determine the efficiency of fertilization using ICSI with chemically activated ovine oocytes and sperm selected by swim up（SU） or swim up ＋ zona pellucida（SU ＋ ZP） ***： Experiment 1, 4–20 replicates with total 821 in vitro matured oocytes were chemically activated with ethanol, calcium ionophore or ionomycin, to determine oocyte activation（precense of one PN）. Treatments showed similar results（54, 47, 42 %, respectively） but statistically differents（P 0.05）.Conclusions： Chemical activation induces higher ovine oocyte activation than mechanical activation. Ethanol slightly displays higher oocyte activation than calcium ionophore and ionomicine. Sperm selection with SU ＋ ZP increased AR/A and AR/D rates in comparison with SU in fresh and frozen-thawed sperm. According to this, in terms of fertilization rates, chemical activation after ICSI increased oocyte PN formation compared to mechanical activation. Also, fresh sperm treated with SU and SU ＋ ZP were significantly different than frozen-thawed sperm,but between sperm treatments no significant differences were obtained.

关键词： Ethanol ICSI Oocyte activation Ovine Pronucleus Zona pellucida

Changing delta hepatitis patient profile:A single center experience in Valencia region,Spain

在线全文

学校读者我要写书评

暂无评论

World Journal of Hepatology 2020年第6期12卷 277-287页

作者： Helena hernàndez-Èvole Álvaro Briz-Redón Marina Berenguer Departament de Medicina University of ValènciaValencia 46010Spain Statistics Office City Council of ValènciaValencia 46002Spain Liver Transplantation and Hepatology Unit Hospital Universitari I Politècnic La FeValencia 46026Spain CIBERehd Instituto de Salud Carlos ⅢMadrid 28029Spain ISS La fe Valencia 46026Spain

BACKGROUND Delta hepatitis is a rare infection with an aggressive disease *** almost three decades,however,there have been no epidemiological studies in our traditionally endemic *** To investigate the prevalence of delta hepatitis in a sample of patients with chronic hepatitis B virus(HBV)infection followed at a Hepatology Unit in Valencia,*** Retrospective evaluation of anti-hepatitis D virus-immunoglobulin G seroprevalence among patients with chronic HBV infection(n=605)followed at a reference Hepatology Unit in *** The prevalence of anti-hepatitis D virus-immunoglobulin G among HBV-infected patients was 11.5%:Male(63%)and median age of 52 *** majority were born in Spain(67%)and primarily infected through intravenous drug ***,a significant percent(24.5%),particularly those diagnosed in more recent years,were migrants presumably nosocomially *** such as diabetes(8.5%),obesity/overweight(55%),and alcohol consumption(34%)were frequent.A high proportion of patients developed liver complications such as cirrhosis(77%),liver decompensation(81%),hepatocellular carcinoma(HCC)(16.5%),or required liver transplantation(LT)(59.5%).Diabetes was associated with progression to cirrhosis,LT,and *** sex,increasing age,and alcohol were associated with LT and *** to HBV mono-infected patients,delta individuals developed cirrhosis and liver decompensation more frequently,with no differences in HCC *** Patients infected in the 1980’s were mostly locals infected through intravenous drug use,whereas those diagnosed recently are frequently non-Spanish natives from endemic *** of their origin,patients are predominantly male with significant comorbidities,which potentially play a major role in disease *** confirm a high rate of subsequent liver complications.

关键词： Viral hepatitis Delta hepatitis Cirrhosis Liver transplantation Immigration Valencia

Hydrothermal Synthesis and Characterization of Europium-doped Barium Titanate Nanocrystallites

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano-Micro Letters 2013年第1期5卷 57-65页

作者： Margarita García-hernndez Geneviève Chadeyron Damien Boyer Antonieta García-Murillo felipe Carrillo-Romo Rachid Mahiou Universidad Autónoma Metropolitana Departamento de Ciencias NaturalesDCNIUnidad CuajimalpaPedro Antonio de los Santos 8411850 Mxico D.F. Mxico Clermont Universit Institut de Chimie de Clermont-ferrand UMR 6296CNRS/UBP/ENSCCFBP 10448F-63000 Clermont-Ferrand Instituto Politcnico Nacional CIITEC IPNCerrada de Cecati S/N. Col. Santa CatarinaAzcapotzalco Mxico D.F. C.P. 02250Mxico

Barium titanate nanocrystallites were synthesized by a hydrothermal technique from barium chloride and tetrabutyl titanate. Single-crystalline cubic perovskite Ba TiO_3 consisting of spherical particles with diameters ranging from 10 to 30 nm was easily achieved by this route. In order to study the influence of the synthesis process on the morphology and the optical properties, barium titanate was also prepared by a solid-state reaction. In this case, only the tetragonal phase which crystallizes above 900 was observed. High-temperature X-ray diffraction measurements were performed to investigate the crystallization temperatures as well as the particle sizes via the Scherrer formula. The lattice vibrations were evidenced by infrared spectroscopy. Eu^(3+)was used as a structural probe, and the luminescence properties recorded from Ba TiO_3 :Eu^(3+)and elaborated by a solid-state reaction and hydrothermal process were compared. The reddish emission of the europium is increased by the nanometric particles.

关键词： BaTiO3 Europium Nanocrystallites Hydrothermal technique

Accuracy of tree mapping based on hand-held laser scanning comparing leaf-on and leaf-off conditions in mixed forests

在线全文

学校读者我要写书评

暂无评论

Journal of forestry Research 2024年第5期35卷 14-25页

作者： frederico Tupinambá-Simões Adrián Pascual Juan Guerra-hernández Cristóbal Ordóñez Tiago de Conto felipe Bravo iufOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIAValladolidSpain Department of Geographical Sciences University of MarylandCollege ParkMD 20742USA forest Research Centre School of AgricultureUniversity of LisbonTapada da Ajuda1349‑017 LisbonPortugal

The use of mobile laser scanning to survey forest ecosystems is a promising,scalable technology to describe forest 3D structures at high *** confirm the con-sistency in the retrieval of forest structural parameters using hand-held laser scanning(HLS),before operationalizing the method,confirming the data is *** analyzed the per-formance of tree-level mapping based on HLS under differ-ent phenology conditions on a mixed forest in western Spain comprising Pinus pinaster and two deciduous species,Alnus glutinosa and Quercus *** area was surveyed twice during the growing season(July 2022)and once in the deciduous season(february 2022)using several scan-ning *** reference data(418 trees,15 snags)was used to calibrate the HLS data and to assess the influence of phenology when converting 3D data into tree-level attrib-utes(DBH,height and volume).The HLS-based workflow was robust at isolating tree positions and recognizing stems despite changes in ***-six percent of all pairs matched below 65 *** DBH,phenology barely altered *** observed a strong agreement when comparing HLS-based tree height *** values exceeded 2 m when comparing height measurements,confirming height data should be carefully used as reference in remote sensing-based inventories,especially for deciduous *** volume was more precise for pines(r=0.95,and rela-tive RMSE=21.3–23.8%)compared to deciduous species(r=0.91–0.96,and relative RMSE=27.3–30.5%).HLS data and the forest structural complexity tool performed remark-ably,especially in tree positioning considering mixed forests and mixed phenology conditions.

关键词： Precision forestry forest monitoring Mobile laser scanning forest inventory

Spectral feature characterization and nitrogen content prediction in soils with different particle sizes and moisture contents

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Agricultural and Biological Engineering 2008年第1期1卷 43-50页

作者： He Yong Shao Yongni Annia García Pereira Antihus Alexander hernández Gómez Cen Haiyan College of Biosystems Engineering and food Science Zhejiang University268 Kaixuan RoadHangzhou 310029China

The objective of this research is to analyze the influences of light source incidence angle,fiber height,moisture content,and particle size on loamy mixed soil ***(N)content calibration and cross-validation models at different moisture contents and particle sizes were obtained using partial least squares(PLS)*** data were collected using a *** height of 100 mm and light source angle at 45°were chosen to obtain the sharpest spectra without apparent scattering *** results show that moisture content and particle size strongly influenced the absorbance of the spectra,and a better N prediction model was obtained when the particle sizes were in the ranges of 0.5-1.0,1.0-2.0 and 2.0-5.0 mm,with the correlation coefficients(r)of 0.819,0.815 and 0.818,and standard errors of prediction(SEP)of 2.29,2.41 and 2.42 mg/kg,*** N prediction model was obtained when the soil was kept in its natural moisture content with r of 0.575 and SEP of 3.275 mg/kg,compared to the performance of dried soil samples with r of 0.815 and SEP of 2.425 mg/kg.

关键词： spectral feature prediction model soil moisture nitrogen content near infrared reflectance spectroscopy partial least squares

Diplopoda in the world fossil record

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Zoological Systematics 2024年第3期49卷 185-245页

作者： Michelle Álvarez-Rodríguez francisco Riquelme Miguel hernández-Patricio fabio Cupul-Magaña Laboratorio de Sistemática Molecular Escuela de Estudios Superiores del JicareroUniversidad Autónoma del Estado de MorelosC.P.62909JojutlaMorelosMexico MMRN Centro de Investigaciones BiológicasUniversidad Autónoma del Estado de MorelosC.P.62209CuernavacaMorelosMexico Unafíliate Centro Universitario de la Costa Universidad de GuadalajaraC.P.48280Puerto VallartaJaliscoMexico

We present a comprehensive catalog with an updated database of the fossil record of Diplopoda in the *** data was collected from descriptions and reports published from 1854 to the *** also include new records from Mexican amber(Upper Oligocene-Lower Miocene),counting 83 unknown fossil inclusions,with the first records of the orders Polyxenida,Platydesmida,and Julida,as well as the families Sphaeriodesmidae and Trichopolydesmidae within *** to our results,Diplopoda counts 413 records featuring 299 distinct taxa ranging from the Middle Silurian to the Upper Pleistocene,representing three subclasses,two subterclasses,six superorders,25 orders,15 superfamilies,55 families,93 genera,and 161 fossil *** date,no fossils of the order Siphonocryptida have been *** fossil record extends over three geological eras:the Paleozoic,with 161 taxa,including 97 species;the Mesozoic,with 53 taxa and 22 species;and the Cenozoic,with 85 taxa and 42 *** referred material shows different forms of fossil *** comprises 123 impressions,99 compressions,26 ichnites,predominantly from Paleozoic and Mesozoic sediments,and 165 amber inclusions from late Mesozoic and Cenozoic ***,this catalog allows us to estimate the size and taxonomic composition of Diplopoda in the fossil record worldwide.

关键词： Millipedes Paleozoic Mesozoic Cenozoic new records catalog

When a general morphology allows many habitat uses

在线全文

学校读者我要写书评

暂无评论

Integrative Zoology 2016年第6期11卷 483-499页

作者： María J.TULLI félix B.CRUZ Tiana KOHLSDORf Virginia ABDALA Unidad Ejecutora Lillo(CONICET)Instituto de Herpetología Fundación Miguel LilloTucumánArgentina Instituto de Investigaciones en Biodiversidad y Medioambiente(INIBIOMA)CONICET-UNCOMA BarilocheRío NegroArgentina Departamento de Biologia-ffCLRP Universidade de São PauloRibeirão PretoBrazil Instituto de Biodiversidad Neotropical UNT-CONICETCátedra de Biología GeneralFacultad de Ciencias Naturales e IMLTucumánArgentina

During the last decades the study of functional morphology received more attention incorporating more detailed data corresponding to the internal anatomy that together contribute for a better understanding of the functional basis in *** we focus on 2 lizard families,Tropiduridae and Liolaemidae,and use information related to muscle-tendinous and external morphology traits of hind *** investigate whether the value of the traits analyzed tend to exhibit a reduced phenotypic variation produced by stabilizing selection,and whether species showing specialization in their habitat use will also exhibit special morphological features related to *** a result,we identified that evolution of hind limb traits is mainly explained by the Ornstein-Uhlenbeck model,suggesting stabilizing *** and tropidurids show clear ecomorphological trends in the variables considered,with sand lizards presenting the most specialized morphological *** ecomorphological trends differ between the 2 lineages,and traits of internal morphology tend to be more flexible than those of external morphology,restricting the ability to identify ecomorphs shared between these 2 *** traits of external morphology likely explain such restriction,as ecomorphs have been historically defined in other lizard clades based on variation of external morphology.

关键词： external morphology Lioalemidae muscles tendon Tropiduridae

Phosphorus fractions and sorption dynamics in the sediments of two Ca-SO4 water reservoirs in the central Argentine Andes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Sediment Research 2017年第3期32卷 442-451页

作者： José Gabriel León fernando Luis Pedrozo Pedro félix Temporetti Instituto Argentino de Nivología Glaciología y Ciencias Ambientales (IANIGLA)CCT Mendoza Departamento General de Irrigación Gobierno de Mendoza Espaa y Barcala Instituto de Investigaciones en Biodiversidad y Medio Ambiente (INIBIOMA) CONICET-Universidad Nacional del Comahue

Phosphorus（P） fractionation and sorption behavior were studied in the sediments of two calcium-sulfate(Ca-SO4: Ca2+170 mg L-1; SO42-400 mg L-1) water reservoirs in the southern central Argentine Andes-El Carrizal Reservoir（ECR）,which stratifies in summer and El Nihuil Reservoir（ENR）,which is vertically mixed throughout the year. Sediment size classes reflected the lithology of both basins and the reservoirs relative location: ECR（downstream from a valley adjacent to a mountain environment） had higher clay proportions while the sand fraction was more important in ENR（just next to a mountain environment）.In both reservoirs, the chemical composition revealed low alteration and calcium enrichment. Total P content was relatively high(1.1-1.6 mg P kg-1dry weight) as expected from the contribution of marine formations. P fractionation was dominated by Ca-P（ECR, 69% and ENR, 63%） followed by organic-P（23%）in summer-anoxic ECR and by iron/aluminum（fe/Al）-P（27%） in oxic ENR. Batch experiments showed that sorption behavior in ECR had a typical Langmuir isotherm plot while in ENR that model fitted only at low dissolved P values(fe/Al-P content in anoxic（ECR） vs. oxic（ENR） sediments results from the P released from iron-bound phosphorus due to sulfate reduction-ferrous sulfide formation in an anoxic environment. This condition should enable ECR sediments to adsorb P into fresh oxidized iron,and ENR sediments to co-precipitate P with calcium due to fe/Al-P saturation, as observed in batch experiments. This paper constitutes the first description of phosphorus content and dynamics in reservoir sediments in arid central western Argentina, where water sulfate concentrations are naturally high due to basin lithology.

关键词： Reservoir Internal load Phosphorus binding Calcareous watershed Southern Central Andes