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Female mate choice based on pheromone content may inhibit reproductive isolation between distinct populations of Iberian wall lizards

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Current Zoology 2013年第2期59卷 210-220页

作者： Marianne GABIROT Pilar lopez Jose MARTIN Departement Ecologie Comportementale (U.M.R. 5175) CEFE-CNRS 1919 Route de Mende F34293 Montpellier Cedex 5 France Departamento de Ecologia Evolutiva Museo Naeional de Ciencias Naturales C.S.I.C. Jos6 Guti6rrez Abascal 2 28006 Madrid Spain

The Iberian wall lizard Podarcis hispanica forms part of a species complex with several morphologically and geneti- cally distinct types and populations, which may or may not be reproductively isolated. We analyzed whether female mate choice based on males＇ chemical signals may contribute to a current pre-mating reproductive isolation between two distinct populations of P. hispanica from central Spain. We experimentally examined whether females choose to establish territories on areas scent-marked by males of their own population, versus areas marked by males of the other population. Results showed that fe- males did not prefer scent-marks of males from their own population. In contrast, females seemed to attend mostly to among-individual variation in males＇ pheromones that did not differ between populations. Finally, to test for strong premating re- productive isolation, we staged intersexual encounters between males and females. The population of origin of males and females did not affect the probability nor the duration of copulations. We suggest that the different environmental conditions in each population might be selecting for different morphologies and different chemical signals of males that maximize efficiency of communication in each environment. However, females in both populations based mate choice on a similar condition-dependent signal of males. Thus, male signals and female mate choice criteria could be precluding premating reproductive isolation between these phenotypically ＂distinct＂ populations [Current Zoology 59 （2）： 210-220, 2013].

关键词： Podarcis hispanica Chemical communication Mate preferences Mate recognition Species recognition Conflict

Effect of an electron gas on a neutron-rich nuclear pasta

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Nuclear Science and Techniques 2015年第2期26卷 75-82页

作者： Jorge Alberto lopez Enrique Ramirez-Homs Department of Physics University of Texas at El Paso

We studied the role that electron gas has on the formation of nuclear structures at subsaturation densities and low temperatures(T<1 Me V).Using a classical molecular dynamics model we studied isospin symmetric and asymmetric matter at subsaturation densities and low temperatures varying the Coulomb interaction *** effect of such variation was quantified on the fragment size multiplicity,the inter-particle distance,the isospin content of the clusters,the nucleon mobility and cluster persistence,and on the nuclear structure *** found that the presence of an electron gas distributes matter more evenly,disrupts the formation of larger objects,reduces the isospin content,and modifies the nucleon average displacement,but does not affect the inter-nucleon distance in *** nuclear structures are also found to change shapes by different degrees depending on their isospin content,temperature and density.

关键词：电子气体分子动力学模型面食中子相互作用强度核结构同位旋平均位移

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

Relationship of sperm plasma membrane andacrosomal integrities with sperm morphometry inBos taurus

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Asian Journal of Andrology 2020年第6期22卷 578-582页

作者： Inmaculada Palacin Pilar Santolaria Carlos Alquezar-Baeta Carles soler Miguel A Silvestre Jesus Yaniz BIOFITER Research Group Environmental Sciences Institute(IUCA)Department of Animal Production and Food SciencesUniversity of ZaragozaHuesca 22071Spain Department of Computer Science University of ZaragozaZaragoza 50018Spain Department of Cellular Biology Functional Biology and Physical AnthropologyUniversity of ValenciaBurjassot 46100Spain

To date,sperm morphometric studies have assessed whole sperm populations without considering sperm *** aim of this study was to evaluate the relati on ship of sperm membrane and acrosomal integrity with sperm morphometry in liquid semen samples collected from *** this end,sperm morphometry was performed on cryopreserved semen samples from 16 bulls by a combination of fluorescent dyes,including Hoechst 33343,carboxyfluorescein diacetate,and propidium *** allowed discrimination of different subpopulations on the basis of sperm membrane and acrosomal integrity and analysis of the morphometries of the sperm head,nucleus,and acrosome using a specific plug-in module created on *** integrity was related to sperm morphometry as the heads of spermatozoa with a damaged acrosome were significantly smaller than those with a normal acrosome(P<0.001).In the case of spermatozoa with an intact acrosome,those with a damaged plasma membrane had a larger sperm head and acrosome than spermatozoa with an intact plasma membrane(P<0.001).No significant differences in the sperm head size were observed between sperm subpopulations without an acrosome or in the nuclear sperm morphometry of the different *** was a positive correlation between the sperm motility values of the samples and the morphometric parameters for in tact *** correlations were particularly strong for the morphometric parameters of the sperm *** conclude that there are clear differences in the sperm morphometry depending on the status of the sperm membrane and acrosome and this should be considered when performing this kind of analysis.

关键词： Bos taurus fluoresce nee microscopy image analysis sperm morphometry sperm quality

Genotype-based precision nutrition strategies for the prediction and clinical management of type 2 diabetes mellitus

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World Journal of Diabetes 2024年第2期15卷 142-153页

作者： Omar Ramos-lopez Medicine and Psychology School Autonomous University of Baja CaliforniaTijuana 22390Baja CaliforniaMexico

Globally,type 2 diabetes mellitus(T2DM)is one of the most common metabolic disorders.T2DM physiopathology is influenced by complex interrelationships between genetic,metabolic and lifestyle factors(including diet),which differ between populations and geographic *** fact,excessive consumptions of high fat/high sugar foods generally increase the risk of developing T2DM,whereas habitual intakes of plant-based healthy diets usually exert a protective ***,genomic studies have allowed the characterization of sequence DNA variants across the human genome,some of which may affect gene expression and protein functions relevant for glucose *** comprehensive literature review covers the impact of gene-diet interactions on T2DM susceptibility and disease progression,some of which have demonstrated a value as biomarkers of personal responses to certain nutritional ***,novel genotype-based dietary strategies have been developed for improving T2DM control in comparison to general lifestyle ***,progresses in other omics areas(epigenomics,metagenomics,proteomics,and metabolomics)are improving current understanding of genetic insights in T2DM clinical *** more investigation is still needed,the analysis of the genetic make-up may help to decipher new paradigms in the pathophysiology of T2DM as well as offer further opportunities to personalize the screening,prevention,diagnosis,management,and prognosis of T2DM through precision nutrition.

关键词： Type 2 diabetes mellitus Nutrigenetics Single nucleotide polymorphism Genotype Diet Precision nutrition

EBSD Investigation on Effect of Cooling Rate on Microstructure and Transformation Textures of High Strength Hot-rolled Steel Plates

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Journal of Iron and Steel Research International 2016年第3期23卷 261-269页

作者： Nancy M.lopez GRANADOS Armando SALINAS RODRIGUEZ Department of Metallurgical Engineering and Materials Science Center of Research and Advanced StudiesCINVESTAV-Unidad Saltillo

The effect of cooling rate on the microstructure and transformation textures of high strength hot-rolled steels was *** treated samples subjected to different cooling conditions were characterized by optical and scanning electron microscopes using orientation imaging microscopy（OIM）.The experimental results demonstrate that there is a significant effect of cooling rate on microstructures and textures resulting from phase *** cooling rates lead to the appearance of the cube（001）[010],rotated cube（001）[110]/（001）[110],Goss（110）[001]and rotated Goss（110）[110]*** contrast,textures developed at rapid cooling rates are preferably of Cu（112）[111],Br（110）[112],transformed Cu（113）[110]and transformed Br（332）[113]/（112）[131].These texture changes are attributed to the selective character of the phase *** OIM technique was used to have a better understanding of the formation of phases and their relationship between microstructure and processing *** volume fraction of micro-constituents resulting from phase transformation such as bainite,martensite and different types of ferrite,can be measured satisfactorily by this technique correlating image quality of EBSD patterns to specific phases.

关键词： orientation imaging microscopy texture phase transformation microstructure steel

Genetic, metabolic and environmental factors involved in the development of liver cirrhosis in Mexico

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World Journal of Gastroenterology 2015年第41期21卷 11552-11566页

作者： Omar Ramos-lopez Erika Martinez-lopez Sonia Roman Nora A Fierro Arturo Panduro Department of Molecular Biology in Medicine Civil Hospital of Guadalajara "Fray Antonio Alcalde" Guadalajara Jalisco Mexico and Health Sciences Center University of Guadalajara

Liver cirrhosis(LC) is a chronic illness caused by inflammatory responses and progressive fibrosis. Globally, the most common causes of chronic liver disease include persistent alcohol abuse, followed by viral hepatitis infections and nonalcoholic fatty liver disease. However, regardless of the etiological factors, the susceptibility and degree of liver damage may be influenced by genetic polymorphisms that are associated with distinct ethnic and cultural backgrounds. Consequently, metabolic genes are influenced by variable environmental lifestyle factors, such as diet, physical inactivity, and emotional stress, which are associated with regional differences among populations. This Topic Highlight will focus on the genetic and environmental factors that may influence the metabolism of alcohol and nutrients in the setting of distinct etiologies of liver disease. The interaction between genes and environment in the current-day admixed population, Mestizo and Native Mexican, will be described. Additionally, genes involved in immune regulation, insulin sensitivity, oxidative stress and extracellular matrix deposition may modulate the degree of severity. In conclusion, LC is a complex disease. The onset, progression, and clinical outcome of LC among the Mexican population are influenced by specific genetic and environmental factors. Among these are an admixed genome with a heterogenic distribution of European, Amerindian and African ancestry; a high score of alcohol consumption; viral infections; a hepatopathogenic diet; and a high prevalence of obesity. The variance in risk factors among populations suggests that intervention strategies directed towards the prevention and management of LC should be tailored according to such population-based features.

关键词： Genomic medicine Polymorphisms Viral hepatitis Obe

Sperm kinematic, head morphometric and kinetic- morphometric subpopulations in the blue fox （Alopex lagopus）

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Asian Journal of Andrology 2017年第2期19卷 154-159页

作者： Caries soler Jesus Contell Lorena Bori Maria Sancho Almudena Garcia-Molina Anthony Valverde Jan Segarvall Department of Functional Biology and Physical Anthropology University of Valencia 46100 Burjassot Spain R+D Department Proiser R+D Scientific Park University of Valencia 46980 Paterna Spain Technological Institute of Costa Rica San Carlos Campus School of Agronomy 223-21001 Alajuela Costa Rica Finnish Fur Breeders Association ProFur 65101 Vaasa Finland

This work provides information on the blue fox ejaculated sperm quality needed for seminal dose calculations. Twenty semen samples, obtained by masturbation, were analyzed for kinematic and morphometric parameters by using CASA-Mot and CASA-Morph system and principal component （PC） analysis. For motility, eight kinematic parameters were evaluated, which were reduced to PC1, related to linear variables, and PC2, related to oscillatory movement. The whole population was divided into three independent subpopulations： SP1, fast cells with linear movement; SP2, slow cells and nonoscillatory motility; and SP3, medium speed cells and oscillatory movement. In almost all cases, the subpopulation distribution by animal was significantly different. Head morphology analysis generated four size and four shape parameters, which were reduced to PC 1, related to size, and PC2, related to shape of the cells. Three morphometric subpopulations existed. SPI： large oval cells; SP2： medium size elongated cells; and SP3. small and short cells. The subpopulation distribution differed between animals. Combining the kinematic and morphometric datasets produced PC1, related to morphometric parameters, and PC2, related to kinematics, which generated four sperm subpopulations - SPI.. high oscillatory motility, large and short heads; SP2; medium velocity with small and short heads; SP3. slow motion small and elongated cells; and SP4. high linear speed and large elongated cells. Subpopulation distribution was different in all animals. The establishment of sperm subpopulations from kinematic, morphometric, and combined variables not only improves the well-defined fox semen characteristics and offers a good conceptual basis for fertility and sperm preservation techniques in this species, but also opens the door to use this approach in other species, included humans.

关键词： integration of motility and morphology principal component analysis sperm morphometry subpopulation

Updating semen analysis:a subpopulation approach

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Asian Journal of Andrology 2020年第1期22卷 118-119页

作者： Almudena Garcia-Molina Anthony Valverde Daznia Bompart Carina Caldeira Alberto Vendrell Carles soler Proiser R+D S.L. Scientific ParkUniversitat de ValenciaPaterna 46980ValenciaSpain Department of Functional Biology and Physical Anthropology University of ValenciaBurjassot 46100ValenciaSpain Technological Institute of Costa Rica San Carlos CampusSchool of AgronomyAlajuela 223-21001Costa Rica

Dear Editor,Reproductive problems affect 8%-12%of human populations worldwide;40%-50%of all infertility cases are due to the male,and up to 2%of men have suboptimal sperm quality.

关键词： dating cases infertility