检索结果-南通市图书馆

Pharmacological Control of Estrus in Tropical Cattle,an Economical Assessment of Different Synchronization Protocols

引用

Open journal of Veterinary Medicine 2012年第3期2卷 151-157页

作者： juan j.Molina Ivan Molina Alejandro jimenez Carlos S.Galina juan j.romero Asesor Laboratorios Intervet Schering Plough BogotaColombia Director Tecnico Agropecuaria Las Tinajas S.A. BogotaColombia Departamento de Reproduccion Facultad de Medicina Veterinaria y ZootecniaUniversidad Nacional Autonoma de MexicoMexico CityMexico Programa de Investigacion en Medicina Poblacional Escuela de Medicina VeterinariaUniversidad NacionalHerediaCosta Rica Campus Benjamín Nunez HerediaCosta Rica

To compare the fertility results and to assess the cost-effectiveness of several synchronization protocols applied under the conditions of beef cattle enterprises in Colombia, 1658 multiparous zebu crossbred cows mostly Brahman and Nelore ranging between 2 - 6 parities were used. Five protocols of pharmacological treatments varying in hormones used, dosage and the time of application were tested. All cows were inseminated at 52 h by appointment. Pregnancy diagnosis was undertaken over 45 d after insemination by rectal palpation. The total cost per cow and the total cost per gestation, for each protocol, were calculated. Taking a herd of one-hundred cows as baseline for calculations, it was estimated the cost of the total amount of pregnancies possibly obtained in each protocol;then, the excess between the costs of a pregnant cow and the cost of a treated cow was estimated. Additionally, the costs due to cows empty after four services were calculated. A total of 874 pregnancies were registered (52.7%), with pregnancies per protocol varying between 46.9% and 66.2% (p < 005). The cost per treated cow, varied between $64.08 and $97.47 and the cost per gestation from $126.01 to $177.26, without association between the cost of the treatment and the pregnancy rate. Protocol A was the best cost-effective with the lowest additional costs, the lowest amount of open days (2107.7 to 2231.7 d) and IA straws (average = 134), with an additional costs of $6940.00. Synchronization of estrus using pharmacological products seems to have a place in the management of cattle;however, caution should be called upon a careful assessment both from the part of the farm and the professional in charge of the enterprise to avoid using the technique indiscriminatively thus propitiating the use of a method that might not be cost efficient.

关键词： Tropics Bos Indicus Cost-Benefit Estru Synchronization

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Prevalence of Psittacine Beak and Feather Disease Virus and Avian Polyomavirus in Captivity Psittacines from Costa Rica

引用

Open journal of Veterinary Medicine 2013年第4期3卷 240-245页

作者： Gaby Dolz jessica Sheleby-Elías juan j.romero-Zuniga Bernardo Vargas-Leiton Gustavo Gutiérrez-Espeleta Kenneth Madriz-Ordenana Laboratorio de Entomología y Medicina Poblacional Programa MEDPOBEscuela de Medicina VeterinariaUniversidad NacionalHerediaCosta Rica Maestría en Enfermedades Tropicales Posgrado Regional en Ciencias Veterinarias TropicalesEscuela de Medicina VeterinariaUniversidad NacionalHerediaCosta Rica Escuela de Biología Universidad de Costa RicaSan JoseCosta Rica Biotécnica Análisis Moleculares San JoseCosta Rica

Psittacine beak and feather disease virus (PBFDV) and avian polyomavirus (APV) are the most common viral diseases in psittacine birds, both affecting feathers and physical appearance of birds. Between 2005 and 2009, a total of 269 samples were collected from birds presented at veterinary clinics, shelters and rescue centers of wildlife in Costa Rica. They belonged to 19 species of psittacine birds. The most representative species in the sample were Ara macao (157), Ara ambigua (37), Amazona autumnalis (24), Amazon ochrocephala (21) and Ara ararauna (8). A prevalence of 19.7% (53/269) for PBFDV and 4.8% (13/269) for APV was determined using Polymerase Chain Reaction (PCR). In 3.3% (9/269) of the birds mixed infections were detected. Statistical analysis determined that psittacines living in shelters and rescue centers had a greater risk to be positive to PBFDV and APV than birds that were presented at veterinary clinics, while only for PBFDV it was determined, that it is more likely to detect it in feathers than in blood. Finally, birds infected with PBFDV had 6.24 times more probability to become infected with APV, than non-infected birds. This is the first report of prevalence of PBFDV and APV in captive psittacines from Costa Rica.

关键词： Psittacine Beak and Feather Disease Virus Avian Polyomavirus Psittacine Birds Costa Rica

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Thermodynamic property of sandwich cylindrical shell structure with metallic wire mesh:Numerical modeling and experimental analysis

引用

Chinese journal of Aeronautics 2024年第1期37卷 138-152页

作者： Xin XUE Guojian SHEN juan LIAO Institute of Metal Rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou 350116China Fujian Shuikou Power Generation Group Co. LTDFuzhou 350000China

As a new addition to lightweight composite structures,the sandwich cylindrical shell with a metallic wire mesh core has emerged as a promising solution for thermodynamic performance analysis at elevated *** intricate interwoven cellular formations within the metallic wire mesh pose difficulties for thermo-mechanical modeling and property ***,the constitutive models employed to characterize hysteresis phenomena were presented,comprising isotropic elasticity,Bergstrom-Boyce model,Ogden hyper-elasticity,and parameter identification through mechanical examinations at varying ***,the finite element modeling of cylindrical shell structures was determined for modal and steady-state dynamic ***,the experimental procedures were carried out,including the preparation of the sandwich cylindrical shell and the dynamic testing *** first-order natural frequency of the cylindrical shell structure is close to the resonance frequency of the dynamic test results,with a maximum error of 6.5%,demonstrating the accuracy of the simulation *** compared to the solid-core cylindrical shell,the average insertion loss of the sandwich cylindrical shell structure within the frequency range of 10–1000 Hz at room temperature is up to 11.09 ***,at elevated temperatures,the average insertion loss of the sandwich cylindrical shell decreases but fluctuates as the temperature changes.

关键词： Energy dissipation Metallic matrix composites Numerical analysis Sandwich structure Thermodynamic properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Interface property of dissimilar Ti-6Al-4V/AA1050 composite laminate made by non-equal channel lateral co-extrusion and heat treatment

引用

Defence Technology（防务技术） 2024年第3期33卷 197-208页

作者： juan Liao Mengmeng Tian Xin Xue School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350116China

The purpose of this paper is to examine the effect of processing parameters and subsequent heat treatments on the microstructures and bonding strengths of Ti-6Al-4V/AA1050 laminations formed via a non-equal channel lateral co-extrusion *** microstructural evolution and growth mechanism in the diffusion layer were discussed further to optimize the bonding quality by appropriately adjusting process *** electron microscopes(SEM),energy dispersive spectrometer(EDS),and X-ray diffraction(XRD)were used to characterize interfacial diffusion *** shear test was used to determine the mechanical properties of the interfacial diffusion *** experimental results indicate that it is possible to co-extrusion Ti-6Al-4V/AA1050 compound profiles using non-equal channel lateral *** heat treatment processes affect the thickness of the diffusion *** the temperature and time of heat treatment increase,the thickness of the reaction layers increases ***,the shear strength of the Ti-6Al-4V/AA1050 composite interface is proportional to the diffusion layer *** is observed that a medium interface thickness results in superior mechanical performance when compared to neither a greater nor a lesser interface *** characterization of all heat treatments reveals that the only intermetallic compound observed in the diffusion layers is TiAl_(3).Due to the inter-diffusion of Ti and Al atoms,the TiAl_(3) layer grows primarily at AA1050/TiAl_(3) interfaces.

关键词： Shear strength Co-extrusion Heat treatment Microstructure Intermetallic compounds

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Dominance of transposable element‑related satDNAs results in great complexity of“satDNA library”and invokes the extension towards“repetitive DNA library”

引用

Marine Life Science & Technology 2024年第2期6卷 236-251页

作者： Monika Tunjić‑Cvitanić Daniel García‑Souto juan j.Pasantes EvaŠatović‑Vukšić Division of Molecular Biology Ruđer BoškovićInstitute10000 ZagrebCroatia Genomes and Disease Centre for Research in Molecular Medicine and Chronic Diseases(CIMUS)Universidade de Santiago de Compostela15706 Santiago de CompostelaSpain Department of Zoology Genetics and Physical AnthropologyUniversidade de Santiago de Compostela15706 Santiago de CompostelaSpain Centro de Investigación Mariña Dpto de BioquímicaXenética e InmunoloxíaUniversidade de Vigo36310 VigoSpain

Research on bivalves is fast-growing,including genome-wide analyses and genome *** characteristics qualify oysters as a valuable model to explore repetitive DNA sequences and their genome *** we char-acterize the satellitomes of five species in the family Ostreidae(Crassostrea angulata,***,***,***,Ostrea edulis),revealing a substantial number of satellite DNAs(satDNAs)per genome(ranging between 33 and 61)and peculiarities in the composition of their *** satDNAs were either associated to or derived from transposable elements,displaying a scarcity of transposable element-unrelated satDNAs in these *** to the non-conventional satellitome constitution and dominance of Helitron-associated satDNAs,comparative satellitomics demanded more in-depth analyses than standardly *** analyses(including ***,the first bivalve species with a defined satellitome)revealed that 13 satDNAs occur in all six oyster genomes,with Cg170/HindIII satDNA being the most abundant in all of *** the“satDNA library model”highlighted the necessity to adjust this term when studying tandem repeat evolution in organisms with such *** repetitive sequences with potential variation in the organizational form and repeat-type affiliation are examined across related species,the introduction of the terms“TE library”and“repetitive DNA library”becomes essential.

关键词： Satellitome Comparative satellitomics Helitron Bivalves “Dark matter of the genome”

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Temporal stability and directional change in a color cline of a marine snail from NW Spain

引用

Current Zoology 2024年第2期70卷 163-173页

作者： juan Gefaell Ramon Vigo A.Honorato Gonzalez-Vazquez juan Galindo Emilio Rolan-Alvarez Centro de Investigacion Marina Universidade de VigoDepartamento de BioquimicaGenetica e Inmunologia36310 VigoSpain

The evolution and maintenance of color clines is a classic topic of research in evolutionary ***,studies analyzing the temporal dynamics of such clines are much less frequent,due to the difficulty of obtaining reliable data about past color distributions along environmen-tal *** this article,we describe a case of decades-long temporal stability and directional change in a color cline of the marine snail Littorina saxatilis along the coastal inlet of the Ria de Vigo(NW Spain).*** from this area shows a clear color cline with 3 distinct areas from the innermost to the more wave-exposed localities of the Ria:the inner,protected localities show an abundance of fawn-like individuals;the intermediate localities show a high diversity of colors;and the outer,wave-exposed localities show populations with a high frequency of a black and lineated *** compare data from the 1970s and 2022 in the same localities,showing that the cline has kept relatively stable for at least over half a century,except for some directional change and local variability in the frequency of certain *** regression analyses and biodiversity measures are presented to provide clues into the selective pressures that might be involved in the maintenance of this color *** research avenues to properly test the explanatory power of these selective agents as well as the possible origins of the cline are discussed.

关键词： clinal variation color polymorphism ecological gradient Littorina saxatilis natural selection wave exposure.

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Body-force modeling considering induced upstream effects for a transonic compressor with total temperature distortion

引用

Chinese journal of Aeronautics 2024年第6期37卷 7-19页

作者： jiahui QIU Chen YANG Wenqiang ZHANG Min ZHANG juan DU Digital Twin Research Center Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China School of Engineering and Science University of Chinese Academy of SciencesBeijing 100190China National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine Chinese Academy of SciencesBeijing 100190China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

To numerically study the impact of total temperature distortion on a transonic compressor with reduced computational costs,a Body-Force Model(BFM)is ***,the interactions between the distorted flow and the compressor are analyzed using full-annulus Unsteady Reynolds-Averaged Navier-Stokes(URANS)results and the orbit *** is found that the induced swirl distortion and the mass flux nonuniformity are intensified in the compressor upstream flow field.A correction factor is thus added to the BFM to account for the effect of the induced swirl,which is crucial for the accurate representation of distortion transfer in the ***,steady simulations with large-amplitude 180circumferential total temperature distortion are performed using the developed *** is shown that the distorted compressor map simulated with the BFM matches well with URANS *** circumferential phase shift of total temperature and the generation of the additional total pressure distortion across the rotor are in line with the time-averaged URANS flow *** compressor upstream effects on the distorted inflow can also be exactly *** above-mentioned results demonstrate the BFM developed in this paper can effectively capture the distorted flow features inside the compressor,and significantly reduce the computational costs by five orders of magnitude compared with URANS.

关键词： Upstream effect Orbit method Induced swirl distortion Body force model Correction factor Time-averaged URANS

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Vertical Displacement Measurement in a Slow-Moving Sinkhole Using BOTDA

引用

Photonic Sensors 2024年第1期14卷 23-39页

作者： Pascual SEVILLANO javier PRECIADO-GARBAYO jorge SEVIL Francisco GUTIERREZ juan jMARTiNEZ Sonia MARTiN-LOPEZ Miguel GONZALEZ-HERRAEZ Aragon Institute of Engineering Research(I3A) Universidad de ZaragozaZaragoza 50018Spain Electronic Enginering and Communicaton Dpartment EINAUniversidad de ZaragzaZaragza 50018Spain Aragon Photonics Labs. Zaragoza 50009Spain Department of Earth Sciences Universidad de ZaragozaZaragoza 50009Spain Department of Electronics Escuela Politecnica SuperiorUniversidad de AlcalaMadrid 28805Spain

The effectiveness of monitoring and early-warning systems for ground deformation phenomena,such as sinkholes,depends on their ability to accurately resolve the ongoing ground displacement and detect the subtle deformation preceding catastrophic *** sinkholes with a slow subsidence rate and diffuse edges pose a significant challenge for subsidence monitoring due to the low deformation rates and limited lateral strain *** this work,we satisfactorily illustrate the practicality of the Brillouin optical time domain analysis(BOTDA)to measure the spatial-temporal patterns of the vertical displacement in such challenging slow-moving sagging *** assess the performance of the approach,we compare the strain recorded by the distributed optical fiber sensor with the vertical displacement measured by high-precision *** results show a good spatial correlation with the ability to identify the maximum subsidence *** is also a good temporal correlation with the detection of an acceleration phase in the subsidence associated with a flood event.

关键词： Distributed fiber optic sensing(DFOS) vertical displacement measurement slow subsidence rate sinkhole hazard early-warning system

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

引用

Current Zoology 2024年第1期70卷 1-12页

作者： Lucia V.Sommaro juan j.Martinez Marina B.Chiappero Andrea R.Steinmann Cristina N.Gardenal joséW.Priotto Laboratorio de Ecologia Evolutiva y Biogeografia Instituto de Ecorregiones Andinas(INECoA)Universidad Nacional de Jujuy-Consejo Nacional de Investigaciones Cientificas y Tecnicas(CONICET)San Salvador de JujuyJujuyArgentina Instituto de Diversidad y Ecologia Animal(IDEA) Consejo Nacional de Investigaciones Cientificas y Técnicas(CONICET)and Universidad Nacionalde CordobaCordobaArgentina Catedra de Genética de Poblaciones y Evolucion Facultad de Ciencias ExactasFisicas y NaturalesUniversidad Nacional de CordobaCordobaArgentina Grupo de Investigaciones en Ecologia Poblacional y Comportamental(GIEPCO) Instituto de Ciencias de la TierraBiodiversidad y Ambiente(ICBiA)Universidad Nacional de Rio Cuarto-Consejo Nacional de Investigaciones Cientificas y Técnicas(CONICET)Rio CuartoCordobaArgentina

The sex-biased dispersal and kinship dynamics are important factors shaping the spatial distribution of individuals and are key parameters affecting a variety of ecological and evolutionary ***,we studied the spatial distribution of related individuals within a population of corn mice Calomys musculinus in a seasonal cycle to infer dispersal *** sampling was carried out from spring 2005 to winter 2006 in field borders of intensively managed *** data from 346 individuals with 9 microsatellites showed spatial genetic structure was weak for males,but not for *** results indicate a complex spatial kinship dynamic of related females across all ***,contrary to our expectations,dispersal distances decrease with the increase of the population ***,male dispersal distances were greater when population abundance increased and thus the availability of active *** disperse greater distances to mate and sire offspring with distant females as a possible inbreeding avoidance *** study shows that *** is capable of much greater scattering distances than previously reported and that dispersal occurs fluidly and without barriers across the *** indirect benefit of dispersal on individual fitness could be related to relaxing the competition in the natal area and increasing the mating *** study highlights the value of combining genetic relatedness,fieldwork observations,and behavioral data to estimate dispersal at a fine geographical scale.

关键词： dispersal distances kinship dynamics microsatellite small mammals spatial autocorrelation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Anti-abrasion collagen fiber-based membrane functionalized by UiO-66-NH_(2)with ultra-high efficiency and stability for oil-in-water emulsions separation

引用

Chinese journal of Chemical Engineering 2024年第2期66卷 285-297页

作者： Xiaoxia Ye Rixin Huang Zhihong Zheng juan Liu jie Chen Yuancai Lv College of Environmental and Safety Engineering Fuzhou UniversityFuzhou 350108China College of Chemical Engineering Fuzhou UniversityFuzhou 350108China

Membrane separation strategies offer promising platform for the emulsion ***,the low mechanical strength of membrane separation layers and the trade-off between separation flux and efficiency present significant *** this study,we report a CFM@UiO-66-NH_(2)membrane with high separation flux,efficiency and stability,through utilizing a robust anti-abrasion collagen fiber membrane(CFM)as the multifunctional support and UiO-66-NH_(2)by an in-situ growth as the separation *** high mechanical strength of the CFM compensated for the weakness of the separation layer,while the charge-breaking effect of UiO-66-NH_(2),along with the size sieving of its constituent separating layers and the capillary effect of the collagen fibers,contributed to the potential for efficient ***,the CFM@UiO-66-NH_(2)membrane exhibited superhydrophilic properties,making it suitable for separating oil-in-water microemulsions and nanoemulsions stabilized by anionic *** membrane demonstrated remarkable separation efficiencies of up to 99.960%and a separation flux of370.05 L·m^(-2)·h^(-1).Moreover,it exhibits stability,durability,and abrasion resistance,maintaining excellent separation performance even when exposed to strong acids and alkalis without any damage to its structure and *** six cycles of reuse,it achieved a separation flux of 417.97 L·m^(-2)·h^(-1)and a separation efficiency of 99.747%.Furthermore,after undergoing 500 cycles of strong abrasion,the separation flux remained at 124.39 L·m^(-2)·h^(-1),with a separation efficiency of 99.992%.These properties make it suitable for the long-term use in harsh operating *** attribute these properties to the electrostatic effect resulting from the amino group on UiO-66-NH_(2)and its in-situ growth on the CFM,which forms a size-screening separation *** work highlights the potential of the CFM@UiO-66-NH_(2)membrane as an environmentally friendly size-screening

关键词： Collagen fibers Metal-organic frameworks Oil-in-water emulsion separation Size sieving

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：