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Sexual Attitudes among College Students: An Approach in Mexico

Open Journal of Obstetrics and Gynecology 2015年第7期5卷 400-405页

作者： Aurora Montanez-Frausto aliciaálvarez aguirre Georgina Olvera-Villanueva Ma.Teresa Hernández Ramos Nereyda Hernández Nava Ma.del Rocio Rocha-Rdz Department of Nursing and Midwifery Health Sciences DivisionCampus LeónUniversity of GuanajuatoGuanajuatoMexico Nursing Department Campus Health Sciences and EngineeringUniversity of GuanajuatoGuanajuatoMexico School of Nursing Autonomous University of QueretaroSantiago de QuerétaroMexico Department of Nursing Academic Coordination Altiplano RegionAutonomous University of San Luis PotosiSan Luis PotosiMexico Department of Nursing Multidisciplinary Academic Unit Central ZoneAutonomous University of San Luis PotosiSan Luis PotosiMexico

Objective: To develop a predictive model for HIV/AIDS in the sexual behavior of university students from a public university in the state of Guanajuato. Methodology: Correlational study involved 294 university students from 18 to 19 years of age by stratified random sampling. The instruments used were: attitudes, subjective norms, self-efficacy and intentions for HIV/AIDS and sexual behavior. Descriptive statistics, normality test of Kolmogorov-Smirnov test, Spearman correlation and logistic regression was used. Results: In describing sexual behavior of young students at the beginning of sexual life is observed that 61.9% of them have had sexual life, with higher per- centage in men. Of the 182 university students who reported first sexual intercourse used a contraceptive method 138 and 135 specifically used a condom the first time they had sex. The variables that have the ability to predict the sex drive at the start of sexual life, are the attitudes and perceived behavioral control (X2 = 39,638, df = 4, p < 0.000), reporting a 12.6% of explained variance. Conclusions: In general, university students today are perceived as vulnerable to sexual behavior and have safe sex, which leads us to think that protect not get HIV/AIDS and unwanted pregnancies.

关键词： HIV/AIDS Youth Sexual Behavior Attitudes Intentions Subjective Norms

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ON DIFFERENTIAL STRUCTURES OF POLYNOMIAL SPACES IN CONTROL THEORY

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Journal of Systems Science and Systems Engineering 2012年第3期21卷 372-382页

作者： Baltazar aguirre HERNANDEZ Martn Eduardo FRIAS-ARMENTA Fernando VERDUZCO Depto.de Matematicas Universidad Autonoma Metropolitana-lztapalapa.Av.Sn.Rafael Atlixco no.186.Col.Vicentinalztapalapa 09340MexicoD.F. Depto.de Matematicas Universidad de Sonora.Blvd.Luis Encinas y Rosales s/n.Col.CentroHermosilloSonoraMexico.

A valuable number of works has been published about Hurwitz and Schur polynomials in order to known better their properties. For example it is known that the sets of Hurwitz and Schur polynomials are open and no convex sets. Besides, the set of monic Schur polynomials is contractible. Now we study this set using ideas from differential topology, and we prove that the space of Schur complex polynomials with positive leading coefficient, and the space of Hurwitz complex polynomials which leading coefficient having positive real part, have structure of trivial vector bundle, and each space of （Schur complex and real, Hurwitz complex） polynomials has a differential structure diffeomorphic to some known spaces.

关键词： Schur polynomials Hurwitz complex polynomials trivial vector bundle

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The impact of graphene on neural regenerative medicine

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Neural Regeneration Research 2017年第7期12卷 1071-1072页

作者： Noela Rodriguez-Losada Jose A.aguirre Department of Human Physiology Faculty of MedicineUniversity of Malaga and Biomedicine Biomedical ResearchInstitute of Malaga (IBIMA) Campus de Teatinos Malaga Spain

There is increasing interest in studying carbon-based nanomaterials（CBNs）for use in regenerative *** carbon crystalline structures,such as graphene,carbon nanotubes/nanofibers,boron nitride nanosheets/nanotubes and fullerenes,as well as disordered structures,such as diamond-like carbon,glasslike carbon,and amorphous carbon,are now being considered as promising scaffolds（Ferreira et al.,2015;Kabiri et al.,2015）,

关键词： of as or et The impact of graphene on neural regenerative medicine that been form is into on

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An Inchworm-inspired Robot Based on Modular Body, Electronics and Passive Friction Pads Performing the Two-anchor Crawl Gait

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Journal of Bionic Engineering 2018年第5期15卷 820-826页

作者： Flavio Moreira Anthony Abundis Michael aguirre Justin Castillo Pranav A. Bhounsule Robotics and Motion Laboratory Department of Mechanical Engineering The University of Texas at San Antonio One UTSA Circle San Antonio rX78249 USA

We have created an inchworm robot capable of the two-anchor crawl gait on level ground and inclined plane. The main novelty is in the design of the inchworm：（1） three-part body that is 3D printed and actuated by two servo motors to allow a looping and lengthening action, （2） passive friction pads to anchor the feet, each of which may be disengaged using a servo motor actuated lever arm, and （3） modular body and electronics. The robot is about 2 feet （61 cm） in length, has a mass of about 4 kg, and uses an open-loop controller to achieve steady crawling gait. The inchworm robot achieved a speed of 2.54 *** on level ground as well as on an incline plane of 19~. The energy usage as measured by the Mechanical Cost of Transport （a non-dimensional number defined as the energy used per unit weight per unit distance moved） is 3.34. Our results indicate that simple robotic designs that copy the basic features of natural organisms provide a promising alternative over conventional wheeled robots.

关键词： inchworm bioinspiration two-anchor crawl gait 3D printing sliding locomotion cost of transport

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Navigating the controversy regarding antibiotic prophylaxis in acute variceal bleeding

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World Journal of Gastroenterology 2024年第18期30卷 2485-2487页

作者： David aguirre-Villarreal Ignacio García-Juárez Department of Gastroenterology and Liver Transplant Unit Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMexico City 14080Mexico

Antibiotic prophylaxis in patients with cirrhosis and acute variceal bleeding is part of the standard of care according to most clinical ***,with recent evidence arguing against antibiotic prophylaxis,the role of this... 详细信息

关键词： Cirrhosis Acute variceal bleeding Antibiotic prophylaxis Endoscopic band ligation Spontaneous bacterial peritonitis

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Effects of small-scale disturbances and elevation on the morphology,phenology and reproduction of a successful geophyte

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Journal of Plant Ecology 2009年第1期2卷 13-20页

作者： Daniel Gomez-Garcıa Jose´Azorın AJavier aguirre Instituto Pirenaico de Ecologı´a-CSIC Apartado.64E-22700 JacaHuescaSpain A´rea de Ingenierı´a Agroforestal.EPSH Universidad de Zaragoza.Ctra Cuarte s/n.E-22071 HuescaSpain

Aims We aimed to find out how a geophyte,Merendera montana,occupies a wide ecological,elevational and climatic *** occurrence in that environmental array is outstanding not only among geophytes but also in the whole flora of the Iberian Peninsula,where only a very few plants show such an apparent ***,we compared morphological and reproductive traits,and frequency of different types of reproduction in disturbed and undisturbed ***,we have analyzed the phenology of this plant by trying to understand how it manages to spread in an exceptional elevational gradient of 2000 m,with contrasting climatic regimes between the mediterranean and the alpine *** We measured the plant density of *** populations in different types of Pyrenean grasslands either with or without small-scale disturbances at seven sites from the basal to the alpine belt(400–2300 m a.s.l.).In each one of these populations,100 individuals—1200 in total—were uprooted to measure their morphological features as well as type and occurrence of ***(flowering and fruiting dates and leaf lifespan)was estimated using 5 years of records in the studied areas and>200 herbarium sheets from the whole altitudinal rank and collected in the last 30 *** in plant densities were analyzed with non-parametric Mann–Whitney U-test;differences in morphological traits,fruit and seed production associated with disturbance,with one-way analysis of covariance test(general linear model).Finally,linear regression analyses were used to determine the relationships between clonal reproduction and elevation and those between flowering,fruiting and senescence and date and *** Findings In all cases,plant density in disturbed grasslands was significantly higher than in undisturbed *** height and weight,bulb depth,leaf width and bulb and root weight were higher in disturbed *** and undisturbed plots were similar

关键词： Spanish Pyrenees Merendera montana functional traits disturbed grasslands

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Effects of resveratrol and other polyphenols in hepatic steatosis

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World Journal of Gastroenterology 2014年第23期20卷 7366-7380页

作者： Leixuri aguirre Maria Puy Portillo Elizabeth Hijona Luis Buja Nutrition and Obesity Group Department of Nutrition and Food ScienceUniversity of Basque Country (UPV/EHU) and Centro de Investigación Lucio Lascaray01006 VitoriaSpain Centro de Investigación Biomédica en Fisiopatología de la Obesidad y Nutrición (CIBERobn) Instituto de Salud Carlos Ⅲ01006 VitoriaSpain Department of Gastroenterology University of the Basque Country (UPV/EHU)Donostia Hospital and Biodonostia Institute20014 San SebastiánSpain Centro de Investigación Biomédica en Enfermedades Hepáticas (CIBERehd) Instituto de Salud Carlos Ⅲ20014 San SebastianSpain

Non-alcoholic fatty liver disease covers a wide spectrum of liver pathologies which range from simple steatosis to non-alcoholic *** are members of a very large family of plant-derived compounds that can have beneficial effects on human health,and thus their study has become an increasingly important area of human nutrition *** aim of the present review is to compile published data concerning the effects of both isolated polyphenols as well as polyphenol extracts,on hepatocyte and liver fat accumulation under different steatosis-inducing *** results reported clearly show that this group of biomolecules is able to reduce fat accumulation,but further studies are needed to establish the optimal dose and treatment period *** regard to the potential mechanisms of action,there is a good *** anti-lipidogenic effect of polyphenols is mainly due to reduced fatty acid and triacylglycerol synthesis,increased in fatty acid oxidation,and reduced of oxidative stress and *** a general conclusion,it can be stated that polyphenols are biomolecules which produce hepatoprotective *** date,these beneficial effects have been demonstrated in cultured cells and animal ***,studies performed in humans are needed before these molecules can be considered as truly useful tools in the prevention of liver steatosis.

关键词： Polyphenols Resveratrol Quercetin liver Steatosis Non-alcoholic fatty liver disease

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Stand-level biomass models for predicting C stock for the main Spanish pine species

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Forest Ecosystems 2021年第2期8卷 387-402页

作者： Ana aguirre Miren del Río Ricardo Ruiz-Peinado Sonia Condés Department of Natural Systems and Resources School of Forest Engineering and Natural ResourcesUniversidad Politécnica de MadridMadridSpain INIA Forest Research CenterDepartment of Forest Dynamics and ManagementMadridSpain iuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid and INIAValladolidSpain

Background:National and international institutions periodically demand information on forest indicators that are used for global *** other aspects,the carbon accumulated in the biomass of forest species must be *** this purpose,one of the main sources of data is the National Forest Inventory(NFI),which together with statistical empirical approaches and updating procedures can even allow annual estimates of the requested ***:Stand level biomass models,relating the dry weight of the biomass with the stand volume were developed for the five main pine species in the Iberian Peninsula(Pinus sylvestris,Pinus pinea,Pinus halepensis,Pinus nigra and Pinus pinaster).The dependence of the model on aridity and/or mean tree size was explored,as well as the importance of including the stand form factor to correct model ***,the capability of the models to estimate forest carbon stocks,updated for a given year,was also ***:The strong relationship between stand dry weight biomass and stand volume was modulated by the mean tree size,although the effect varied among the five pine *** humidity,measured using the Martonne aridity index,increased the biomass for a given volume in the cases of Pinus sylvestris,Pinus halepensis and Pinus *** that consider both mean tree size and stand form factor were more accurate and less biased than those that do *** models developed allow carbon stocks in the main Iberian Peninsula pine forests to be estimated at stand level with biases of less than 0.2 Mg·ha^(-1).Conclusions:The results of this study reveal the importance of considering variables related with environmental conditions and stand structure when developing stand dry weight biomass *** described methodology together with the models developed provide a precise tool that can be used for quantifying biomass and carbon stored in the Spanish pine forests in specific years when no field data are available.

关键词： Martonne aridity index Dry weight biomass Carbon stock National Forest Inventory Peninsular pine forest Biomass expansion factor

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Mapping aboveground biomass by integrating geospatial and forest inventory data through a k-nearest neighbor strategy in North Central Mexico

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Journal of Arid Land 2014年第1期6卷 80-96页

作者： Carlos A aguirre-SALADO Eduardo J TREVIO-GARZA Oscar A aguirre-CALDERóN Javier JIMNEZ-PREZ Marco A GONZLEZ-TAGLE José R VALDZ-LAZALDE Guillermo SNCHEZ-DíAZ Reija HAAPANEN Alejandro I aguirre-SALADO Liliana MIRANDA-ARAGóN Faculty of Forest Sciences Autonomous University of Nuevo Leon Faculty of Engineering Autonomous University of San Luis Potosi Forestry Program Postgraduate College Haapanen Forest Consulting Faculty of Agronomy and Veterinary Autonomous University of San Luis Potosí

As climate change negotiations progress,monitoring biomass and carbon stocks is becoming an important part of the current forest ***,national governments are interested in developing forest-monitoring strategies using geospatial *** statistical methods for mapping biomass,there is a nonparametric approach called k-nearest neighbor(kNN).We compared four variations of distance metrics of the kNN for the spatially-explicit estimation of aboveground biomass in a portion of the Mexican north border of the intertropical *** derived,climatic,and topographic predictor variables were combined with the Mexican National Forest Inventory(NFI)data to accomplish the *** of distance metrics applied into the kNN algorithm was evaluated using a cross validation leave-one-out *** results indicate that the Most Similar Neighbor(MSN)approach maximizes the correlation between predictor and response variables(r=0.9).Our results are in agreement with those reported in the *** findings confirm the predictive potential of the MSN approach for mapping forest variables at pixel level under the policy of Reducing Emission from Deforestation and Forest Degradation(REDD+).

关键词： k-nearest neighbor Mahalanobis most similar neighbor MODIS BRDF-adjusted reflectance forest inventory the policy of Reducing Emission from Deforestation and Forest Degradation

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The domestication of Cucurbita argyrosperma as revealed by the genome of its wild relative

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Horticulture Research 2021年第1期8卷 1287-1300页

作者： Josue Barrera-Redondo Guillermo Sanchez-de la Vega Jonas A.aguirre-Liguori Gabriela Castellanos-Morales Yocelyn T.Gutierrez-Guerrero Xitlali aguirre-Dugua Erika aguirre-Planter Maud I.Tenaillon Rafael Lira-Saade Luis E.Eguiarte Departamento de Ecologia Evolutiva Instituto de EcologiaUniversidad Nacional Autonoma de MexicoCircuito Exterior s/n Anexo al Jardin Botanico04510 Ciudad de MexicoMexico Department of Ecology and Evolutionary Biology University of CaliforniaIrvineCA 92697USA Departamento de Conservacion de la Biodiversidad El Colegio de la Frontera SurVillahermosaCarretera Villahermosa‐Reforma km 15.5 Rancheria El Guineo 2ªseccion86280 VillahermosaTabascoMexico Genetique Quantitative et Evolution-Le Moulon Universite Paris-SaclayInstitut National de Recherche pour l’Agriculturel’Alimentation et l’EnvironnementCentre National de la Recherche ScientifiqueAgroParisTechGif-sur-Yvette 91190France UBIPRO Facultad de Estudios Superiores IztacalaUniversidad Nacional Autonoma de MexicoAv.de los Barrios#1Col.Los Reyes IztacalaTlalnepantlaEdo.de Mex 54090Mexico

Despite their economic importance and well-characterized domestication syndrome,the genomic impact of domestication and the identification of variants underlying the domestication traits in Cucurbita species(pumpkins and squashes)is currently *** argyrosperma,also known as cushaw pumpkin or silver-seed gourd,is a Mexican crop consumed primarily for its seeds rather than fruit *** makes it a good model to study Cucurbita domestication,as seeds were an essential component of early Mesoamerican diet and likely the first targets of human-guided selection in pumpkins and *** obtained population-level data using tunable Genotype by Sequencing libraries for 192 individuals of the wild and domesticated subspecies of *** across *** also assembled the first high-quality wild Cucurbita *** genomic analyses revealed several structural variants and presence/absence of genes related to *** results indicate a monophyletic origin of this domesticated crop in the lowlands of *** found evidence of gene flow between the domesticated and wild subspecies,which likely alleviated the effects of the domestication *** uncovered candidate domestication genes that are involved in the regulation of growth hormones,plant defense mechanisms,seed development,and *** presence of shared selected alleles with the closely related species Cucurbita moschata suggests domestication-related introgression between both taxa.

关键词： Cucurbita likely pump

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