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Geochemical elements in suspended particulate matter of Ensenada de La Paz Lagoon,Baja California Peninsula,Mexico:Sources,distribution,mass balance and ecotoxicological risks

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Journal of Environmental Sciences 2024年第2期136卷 422-436页

作者： Sandra Soledad Morales-García Pilar de Acacia Pérez-Escamilla Suresh Babu Sujitha Pichaimani Godwyn-Paulson Andrés Felipe Zuniga-cabezas Muthuswamy Ponniah Jonathan Instituto Politécnico Nacional(IPN) Centro Mexicano para la Producción más Limpia(CMPL)Av.Acueducto s/nCol.Barrio la Laguna TicománDel Gustavo A.MaderoC.P.07340Ciudad de MéxicoMexico Instituto Politécnico Nacional(IPN) Escuela Superior de Ingeniería y Arquitectura(ESIA)Unidad Ticomán***án 600Delg.Gustavo A.MaderoC.P.07340Ciudad de México(CDMX)Mexico Instituto Politécnico Nacional(IPN) Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y Desarrollo(CIIEMAD)Calle 30 de Junio de 1520Barrio la Laguna TicománDel.Gustavo A.MaderoC.P.07340Ciudad de MéxicoMéxico

The present study aimed to evaluate multi-element concentrations(Al,As,Ca,Cd,Co,Cr,Cu,Fe,Mg,Mn,Mo,Ni,Pb,Sr)in suspended particulate material(SPM)collected from Ensenada de La Paz(ELP)lagoon,Baja California Sur,Mexico in two different periods(September and May)to comprehend their origin,geochemical behavior,mass transfer and associated ecotoxicological *** 24 hr variation coefficient of volumetric SPM levels were found to be 51.7%in September and 40.5%in May,signifying the effects of oceanic *** calculated enrichment factor(EF)values for all the studied elements were of higher magnitude because of the high surface area and oxide nature of SPM,and in this study,Mo had the highest EF of 46.77 probably due to its origin from continental *** the ecotoxicological perspective,the integrated toxic risk index revealed low toxic risk to the benthic ***,the mean-ERM-Quotient calculated using the particulate concentrations of As,Cd,Cr,Cu,Ni,Pb indicated 9%probability of toxicity to *** comprehensive geochemical and ecotoxicological assessment of particulate metal concentrations in the ELP lagoon signify low to moderate contamination.

关键词： Suspended particulate material Heavy metals Risk assessment Mass transfer Ensenada de La Paz

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Carbapenemases: A worldwide threat to antimicrobial therapy

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World Journal of Pharmacology 2015年第1期4卷 75-95页

作者： José Miguel Sahuquillo-Arce alicia hernández-cabezas Fernanda Yarad-Auad Elisa Ibá?ez-Martínez Patricia Falomir-Salcedo Alba Ruiz-Gaitán Grupo de investigación de infecciones respiratorias Instituto de Investigación Sanitaria-Fundación para la Investigación Hospital La Fe.Torre A46026 ValenciaSpain Servicio de Microbiología Hospital Universitari i Politécnic La Fe46009 ValenciaSpain

Carbapenems are potent β-lactams with activity against extended-spectrum cephalosporinases and β-lactamases. These antibiotics, derived from thienamycn, a carbapenem produced by the environmental bacterium Streptomyces cattleya, were initially used as last-resort treatments forsevere Gram-negative bacterial infections presenting resistance to most β-lactams but have become an empirical option in countries with high prevalence of Extended Spectrum β-lactamase-producing bacterial infections. Imipenem, the first commercially available carbapenem, was approved for clinical use in 1985. Since then, a wide variety of carbapenem-resistant bacteria has appeared, primarily Enterobacteriaceae such as Escherichia coli or Klebsiella pneumoniae(K. pneumoniae), Pseudomonas aeruginosa and Acinetobacter baumannii, presenting different resistance mechanisms. The most relevant mechanism is the production of carbapenem-hydrolyzing β-lactamases, also known as carbapenemases. These enzymes also inactivate all known β-lactams, and some of these enzymes can be acquired through horizontal gene transfer. Moreover, plasmids, transposons and integrons harboring these genes typically carry other resistance determinants, rendering the recipient bacteria resistant to almost all currently used antimicrobials, as is the case for K. pneumoniae carbapenemase- or New Delhi metallo-β-lactamases-type enzymes. The recent advent of these enzymes in the health landscape presents a serious challenge. First, the emergence of carbapenemases limits the currently available treatment options; second, these enzymes pose a risk to patients, as some studies have demonstrated high mortality associated with carbapenemase-producing bacterial infections; and third, these circumstances require an extra cost to sanitary systems, which are particularly cumbersome in developing countries. Therefore, emphasis should be placed on the early detection of these enzymes, the prevention of the spread of carbapenemase-producing b

关键词：碳青霉烯头孢菌素酶治疗方法临床分析

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Nonlinear criterion for strength mobilization in brittle failure of rock and its extension to the tunnel scale

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International Journal of Mining Science and Technology 2022年第4期32卷 685-705页

作者： Rodolfo cabezas Javier Vallejos Faculty of Engineering and Technology Universidad San SebastianSantiagoChile Advanced Mining Technology Center Universidad de ChileSantiagoChile Department of Mining Engineering Universidad de ChileSantiagoChile

As underground excavations are getting deeper and field stresses increase, the behavior of intact rock blocks plays an increasingly important role in understanding and estimating the overall rock mass strength. To model the brittle behavior of intact rock blocks, the stress–strain curve is usually idealized considering a linear strength mobilization approach(cohesion-weakening-friction-strengthening, CWFS),however, it is well recognized that rock presents a nonlinear behavior in terms of the confining *** study extends the strength mobilization in brittle failure of rock using nonlinear criteria. To determine the model parameters, a standard statistical method that uses the complete laboratory stress–strain curves of the intact rock is employed. Several hypotheses of linear and nonlinear models are statistically compared for different types of rock and confining stress levels. Results demonstrate that the best approach to model the brittle failure of rock is to consider a nonlinear strength envelope, such as the Hoek-Brown criterion assuming a residual uniaxial compressive strength different from zero and a mi parameter that increases, both with simultaneous mobilization. This model helps to recreate highconfining conditions and a more realistic transition between peak and post-peak strength. The obtained parameters are discussed and compared with literature values to verify the validity and to develop guidelines for the estimation of parameters, providing an objective mobilization criterion. Finally, the nonlinear model was applied to a finite element code and extended to a tunnel scale in the brittle rock under high-stress conditions. A reasonable fit between the simulations and the in-situ overbreak measurements was found.

关键词： Nonlinear strength Strength mobilization Brittle failure Intact rock Scaling

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Sintering study of Ti6Al4V powders with different particle sizes and their mechanical properties

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International Journal of Minerals,Metallurgy and Materials 2018年第12期25卷 1389-1401页

作者： JoséLuis cabezas-Villa JoséLemus-Ruiz Didier Bouvard Omar Jiménez Héctor Javier Vergara-hernández Luis Olmos University Michoacana of San Nicolás of Hidalgo IIMMMorelia 58060México University Grenoble Alpes CNRSSIMaPGrenoble 38000France University of Guadalajara Departamento de Ingeniería de ProyectosZapopan 45100México National Technological Institute of Mexico I.T.MoreliaMorelia 58120México University Michoacana of San Nicolás of Hidalgo INICITMorelia 58060México

Ti6Al4V powders with three different particle size distributions(0–20, 20–45, and 45–75 μm) were used to evaluate the effect of the particle size distribution on the solid-state sintering and their mechanical properties. The sintering kinetics was determined by dilatometry at temperatures from 900 to 1260°C. The mechanical properties of the sintered samples were evaluated by microhardness and compression tests. The sintering kinetics indicated that the predominant mechanism depends on the relative density irrespective of the particle size used. The mechanical properties of the sintered samples are adversely affected by increasing pore volume fraction. The elastic Young's modulus and yield stress follow a power law function of the relative density. The fracture behavior after compression is linked to the neck size developed during sintering, exhibiting two different mechanisms of failure: interparticle neck breaking and intergranular cracking in samples with relative densities below and above of 90%, respectively. The main conclusion is that relative density is responsible for the kinetics, mechanical properties, and failure behavior of Ti6 Al4 V powders.

关键词： Ti6Al4V powders dilatometry microhardness sintering kinetics compression failure behavior

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South Asian dairy smallholders: A scoping review of practices and zoonoses

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Asian Pacific Journal of Tropical Medicine 2023年第10期16卷 446-452页

作者： Emily Schembri Angus J D Campbell Juan Pablo Villanueva-cabezas Melbourne School of Population and Global Health The University of MelbourneVictoriaAustralia The Nossal Institute for Global Health The University of MelbourneVictoriaAustralia The Peter Doherty Institute for Infection and Immunity The University of Melbourne and the Royal Melbourne HospitalVictoriaAustralia

Objective: To identify and discuss on-farm management practices linked to bacterial zoonosis risk in smallholder dairy farmers in South Asia. Methods: This scoping review was conducted as per the PRISMA-ScR guidelines. Five hundred and two publications were retrieved from five online databases using a comprehensive search strategy. Studies were selected if they discussed a farm management practice which impacted human health within a South Asian country. Results: Twenty-two studies were included. Seven management practices relevant to farmers, livestock and their shared environment were identified including raw milk consumption, farm hygiene management, personal protective equipment uses, animal vaccination, cleaning udders, hand washing and disposal of afterbirth materials. Preventive practices were found to be utilized at lower frequencies compared to risk increasing practices. Awareness of bacterial zoonoses is particularly low within the region. Conclusions: Based on the results of this review, it was determined that improving farmer awareness of bacterial zoonotic diseases may favor several of the presented leverage points within the South Asian smallholder dairy system. Relying on formal school education to improve this awareness may not solve this problem, instead, more focus on accessible and affordable zoonoses education and farming programs is required.

关键词： Management practices Zoonoses Dairy Smallholder system

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机械球磨制备Ni_2FeSb合金的烧结动力学（英文）

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Transactions of Nonferrous Metals Society of China 2016年第8期26卷 2126-2135页

作者： F.ALVARADO-hernández O.JIMéNEZ G.GONZALEZ-CASTANEDA V.BALTAZAR-hernández J.cabezas-VILLA M.ALBITER H.VERGARA-hernández L.OLMOS Unidad Académica de Ingeniería I Universidad Autónoma de ZacatecasJardín Juárez 147 Centro Histórico Zacatecas Zacatecas C. P. 98000 México Departamento de Ingeniería de Proyectos CUCEI Universidad de GuadalajaraBlvd. Marcelino García Barragán 1421 Olímpica Guadalajara Jalisco C. P. 44430 Mexico INICIT Universidad Michoacana de San Nicolás de HidalgoFco. J. Mujica S/N C.U. Morelia Michoacán C. P. 58060 México División de Estudios de Posgrado e Investigación TecNM/Instituto Tecnológico de MoreliaAv. Tecnológico # 1500 Colonia Lomas de Santiaguito Morelia Michoacán C. P. 58120 México

采用粉末冶金工艺制备Ni2FeSb三元形状记忆合金。利用膨胀实验研究合金的烧结动力学；采用XRD和SEM分别考察粉末样品和烧结样品的显微组织和形貌；测定烧结样品表面的显微硬度。结果表明：研磨时间对粉末样品的形状、晶粒尺寸和晶体结... 详细信息

采用粉末冶金工艺制备Ni2FeSb三元形状记忆合金。利用膨胀实验研究合金的烧结动力学；采用XRD和SEM分别考察粉末样品和烧结样品的显微组织和形貌；测定烧结样品表面的显微硬度。结果表明：研磨时间对粉末样品的形状、晶粒尺寸和晶体结构的均匀性具有显著影响。经较长时间研磨的样品具有较高的相对密度和较均匀的元素分布，且为L21和马氏体相，这些性能使合金具有形状记忆功能。在温度为750~1273K条件下，合金的激活能为109~283kJ/mol，这表明烧结过程主要由体积扩散控制。增加研磨时间和加热速率，合金的显微硬度得到提高。

关键词： Ni基形状记忆合金机械球磨固态烧结显微硬度

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The need to develop tailored tools for improving the quality of thematic bibliometric analyses: Evidence from papers published in Sustainability and Scientometrics

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Journal of Data and Information Science 2023年第4期8卷 10-35页

作者： Alvaro cabezas-Clavijo Yusnelkis Milanés-Guisado Ruben Alba-Ruiz Ángel MDelgado-Vázquez Universidad Internacional de La Rioja(UNIR) Avenida de la Paz137Logroño26006Spain Universidad Pablo de Olavide Ctra.de UtreraKm 1Sevilla41013Spain Hospital Universitario Virgen de las Nieves Avenida de las Fuerzas Armadas2Granada 18014Spain

Purpose: The aim of this article is to explore up to seven parameters related to the methodological quality and reproducibility of thematic bibliometric research published in the two most productive journals in bibliometrics, Sustainability(a journal outside the discipline) and Scientometrics, the flagship journal in the ***/methodology/approach: The study identifies the need for developing tailored tools for improving the quality of thematic bibliometric analyses, and presents a framework that can guide the development of such tools. A total of 508 papers are analysed, 77% of Sustainability, and 23% published in Scientometrics, for the 2019-2021 ***: An average of 2.6 shortcomings per paper was found for the whole sample, with an almost identical number of flaws in both journals. Sustainability has more flaws than Scientometrics in four of the seven parameters studied, while Scientometrics has more shortcomings in the remaining three *** limitations: The first limitation of this work is that it is a study of two scientific journals, so the results cannot be directly extrapolated to the set of thematic bibliometric analyses published in journals from all *** implications: We propose the adoption of protocols, guidelines, and other similar tools, adapted to bibliometric practice, which could increase the thoroughness, transparency, and reproducibility of this type of ***/value: These results show considerable room for improvement in terms of the adequate use and breakdown of methodological procedures in thematic bibliometric research, both in journals in the Information Science area and journals outside the discipline.

关键词： Thematic bibliometric analyses Sustainability Scientometrics Reproducibility Methodological quality

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Prevalence of and risk factors for erectile dysfunction in young nondiabetic obese men:results from a regional study

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Asian Journal of Andrology 2020年第4期22卷 372-378页

作者： María Molina-Vega Maite Asenjo-Plaza María JoséBanderas-Donaire María Dolores hernández-Ollero Silvia Rodríguez-Moreno Juan Jálvarez-Millán Pablo cabezas-Sanchez Fernando Cardona-Díaz Juan Alcaide-Torres Lourdes Garrido-Sánchez Daniel Castellano-Castillo Francisco J Tinahones JoséC Fernández-García Department of Endocrinology and Nutrition Virgen de la Victoria University Hospital(IBIMA)Málaga UniversityMálaga 29010Spain Centro de Investigación Biomédica en Red de la Fisiopatología de la Obesidad y Nutrición(CIBEROBN) Instituto de Salud Carlos IIIMadrid 28029Spain Cruz de Humilladero Primary Care Center Málaga 29010Spain Teatinos Primary Care Center Málaga 29010Spain Chemical Sanitary Consulting(CQS Lab) Madrid 28003Spain

Erectile dysfunction(ED),a condition closely related to cardiovascular morbidity and mortality,is frequently associated with *** this study,we aimed to determine the prevalence of ED and evaluate the associated risk factors in a cohort of 254 young(18–49 years)nondiabetic obese(body mass index[BMI]≥30 kg m−2)men from primary *** function(International Index of Erectile Function[IIEF-5]questionnaire),quality of life(Aging Males'Symptoms[AMS scale]),and body composition analysis(Tanita MC-180MA)were *** testosterone was determined using high-performance liquid chromatography–mass *** logistic regression analysis was used to study the factors associated with *** prevalence was 42.1%.Subjects with ED presented higher BMI,waist circumference,number of components of the metabolic syndrome,AMS score,insulin resistance,and a more unfavorable body composition than those without *** logistic regression analysis showed that a pathological AMS score(odds ratio[OR]:4.238,P40%of subjects.A pathological AMS score,the degree of obesity,and age were positively associated with ED,while elevated HDL-cholesterol levels were inversely associated with the odds of presenting *** prospective studies are needed to evaluate the long-term consequences of ED in this population.

关键词： Aging Males'Symptoms score erectile dysfunction International Index of Erectile Function-5 questionnaire obesity testosterone

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Cu-WC复合材料涂层的受限烧结和磨损性能（英文）

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Transactions of Nonferrous Metals Society of China 2017年第10期27卷 2214-2224页

作者： J.L.cabezas-VILLA L.OLMOS H.J.VERGARA-hernández O.JIMéNEZ P.GARNICA D.BOUVARD M.FLORES División de Estudios de Posgrado e Investigación Tec NM/Instituto Tecnológico de Morelia INICIT Universidad Michoacana de San Nicolás de HidalgoFco.J.Mujica S/N Universidad de Guadalajara Departamento de Ingeniería de Proyectos Univ.Grenoble Alpes CNRS SIMa P

采用固态烧结法制备Cu-WC金属基复合材料涂层。将不同体积分数(5%-30%)的WC增强颗粒与Cu颗粒混合,然后在还原性气氛和垂直膨胀计中于1000°C进行烧结。结果表明,复合材料涂层的烧结动力学受基体材料和WC颗粒的影响,WC颗粒能减缓粉末径... 详细信息

采用固态烧结法制备Cu-WC金属基复合材料涂层。将不同体积分数(5%-30%)的WC增强颗粒与Cu颗粒混合,然后在还原性气氛和垂直膨胀计中于1000°C进行烧结。结果表明,复合材料涂层的烧结动力学受基体材料和WC颗粒的影响,WC颗粒能减缓粉末径向和轴向的致密化。复合材料涂层紧实地粘附于基体上,而WC颗粒随机分布在基体中。与未添加增强剂的样品相比,添加了WC增强剂的样品的显微硬度增加,磨损量降低至原来的1/17。样品在载荷为5 N条件下的主要磨损机理为磨粒磨损,当WC增强剂的体积分数为20%时复合涂层的性能最优。

关键词：受限烧结膨胀法干滑动磨损显微硬度金属基复合材料涂层

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Changes in Mediterranean mesocarnivore communities along urban and ex-urban gradients

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Current Zoology 2015年第5期61卷 793-801页

作者： Mariano R. RECIO Carmen M. ARIJA Sara cabezas-DIAZ Emilio VIRGOS School of Surveying University of Otago PO Box 56 Dunedin New Zealand Departamento de Biologia y Geologia Escuela de Ciencias Experimentales y Tecnologia. Universidad Rey Juan Carlos E-28933 Mostoles Madrid. Spain.

Urbanization causes wildlife habitat loss, fragmentation, and the replacement of specialist species by generalists and/or exotic taxa. Because mesocarnivores are particularly vulnerable to habitat modifications, the rapid expansion of urban areas and the increasing trend for ex-urban development occurring in Mediterranean ecosystems may be major drivers of change in mesocarnivore communities. We combined camera trapping and sign surveys to quantify the richness and relative abundance of a set of wild and domestic mesocarnivores. We quantified these variables controlling for the gradient of urbanism, ex-urbanism, and other environmental variables in patches of natural vegetation in the region of Madrid (central Spain), and a non-urbanized control area ~220 km south of Madrid city. Using conditional autoregressive models (CAR) and model selection procedures, we found that urbanization influenced mesocarnivore community composition but this influence was not detrimental for all the species tested. Generalist carnivores such as the red foxVulpes vulpeswere more abundant in urban and ex-urban areas. Ex-urban development creates overlapping areas between wild and domestic species (such as the domestic catFelis catusand the wildcatFelis silvestris) but contact between wild and domestic carnivores in natural areas is unlikely. Detection of species in the control area was very low. Therefore, the impact of urbanization in causing changes in mesocarnivore communities may be less than other factors such as illegal predator culling.

关键词：城市化群落变化地中海梯度变化郊区野生动物外来物种家养动物

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