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Heavy Metals Monitoring in Sediments from Lerma River in West-Central Mexico

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American Journal of Analytical Chemistry 2018年第2期9卷 77-87页

作者： Héctor Hernández-Mendoza María Judith Ríos-Lugo Elizabeth Teresita Romero-Guzmán Lázaro Raymundo Reyes-Gutiérrez Michael E. Ketterer Instituto Nacional de Investigaciones Nucleares Ocoyoacác México Universidad del Centro de México San Luis Potosí México Universidad Autónoma de San Luis Potosí San Luis Potosí México División of Ciencias Básicas e Ingeniería Departmentof Recursos de la Tierra Universidad Autónoma Metropolitana-Lerma (UAM-L) Lerma México Department of Chemistry Metropolitan State University of Denver Denver USA

The aim of this work was to carry out monitoring of some elements considered toxic in sediments from Lerma River. An analytical method was optimized in our laboratory for quantification of nickel (Ni), cobalt (Co), manganese (Mn), arsenic (As), chromium (Cr) and lead (Pb) by using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). Ten sediments were collected along the Lerma River at variable distances and at 20 cm depth. Samples were heated to 60°C to dryness, followed by separation of particle size using a 74-μ No. 200 mesh for homogeneity purposes. 0.2 g of sample underwent microwave-assisted acid digestion, followed by plate evaporation. The samples were dissolved in 10 mL with HNO3 at 5% v/v for ICP-OES analysis. A certified reference material (CRM 8704) was used to evaluate the method’s accuracy and precision. The method showed linearity, precision, accuracy, and limits of quantification and detection acceptable for protocol validation of analytical method. The average results obtained in recovery of CRM 8704 were ~90% and precision was below 7% for all elements. Levels concentration of As, Cr, Pb show high pollution in A1, A7 and A8 sites. Therefore, Co, Mn and Ni can be considered in this study as normal values. In conclusion, concentration levels of As, Cr, Pb in sediments were high according to US-EPA and NOM-147-SEMARNAT/SSA1-2004. The presence of these heavy metals in Lerma River could be due mainly for the emitted from industries, such as pharmaceutical, automotive, metal mechanics and tannery, and urban residual water. Finally, the method developed using ICP-OES has enabled monitoring of these elements in sediments from Lerma River, with possible applications in a routine analytical laboratory.

关键词： ICP-OES Lerma River Sediments US-EPA

Tropical tree community composition and diversity variation along a volcanic elevation gradient

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Journal of Mountain Science 2022年第12期19卷 3475-3486页

作者： Ruben MARTINEZ-CAMILO Manuel MARTINEZ-MELENDEZ Nayely MARTINEZ-MIELENDEZ Derio Antonio JIMENEZ-LOPEZ Mauricio JosE-RIos Unidad Villa Corzo Facultad de IngenieríaUniversidad de Ciencias y Artes de Chiapas30520 Villa CorzoChiapasMexico Instituto de Ciencias Biológicas Universidad de Ciencias y Artes de Chiapas29039 Tuxtla GutiérrezChiapasMexico Eizia A.C. 29045 Tuxtla GutiérrezChiapasMexico Departamento de Conservación de la Biodiversidad El Colegio de la Frontera Sur29290 San Cristóbal de las CasasChiapasMexico Orquidiario y Jardín Botánico de Comitán Secretaría de Medio Ambiente e Historia Natural30106 Comitán de DomínguezChiapasMexico Instituto de Investigación en Gestión de Riesgos y Cambio Climático Universidad de Ciencias y Artes de Chiapas29039 Tuxtla GutiérrezChiapasMexico

Unraveling the factors that determine variation of diversity in tropical mountain systems is a topic for debate in plant *** is especially true in areas where topography is complex due to volcano elevational gradients and where forests are vulnerable to human *** this study we used a set of climatic(temperature,rainfall,and radiation solar),topographic(elevation,slope aspect,and slope orientation)and human disturbance variables to determine their effect on diversity and composition patterns of a tree community,considering three slope aspects of a tropical volcano in southeastern *** sampled trees in seventy 0.1-ha plots distributed on three slope aspects of the Tacanávolcano along an elevational gradient of 1500 to 2500 *** determined diversity patterns(general tree richness,exponential of Shannon index,and pioneer species richness)with linear regression models,and for beta diversity,we used a dissimilarity index(within and between elevational bands 100 m wide).The effect of a set of environmental and human disturbance variables on tree diversity and community composition was analyzed with general linear models and multivariate analyses,*** registered 2,949 individual trees belonging to 176 species and *** average species richness and alpha diversity per plot were 13(standard deviation±6)and 9(±5),*** tree richness and alpha diversity increased in the middle part(unimodal patterns)of the elevational gradient,but pioneer species richness decreased linearly with *** variance explained by general linear models was greater in richness(32%)than in alpha diversity(25.3%).The most important predictor variables were temperature(elevational gradient),which explained the unimodal pattern(richness and alpha diversity increase at intermediate levels of temperature),and slope orientation,which explained the increase in richness and alpha diversity toward the geographic *** temperature had a signific

关键词： Composition Environmental gradient Tree diversity patterns Tropical humid cloud forest Tropical volcanoes

Quantification of Mayor Volatile Compounds from Artisanal Agave Distilled: Bacanora

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American Journal of Analytical Chemistry 2013年第11期4卷 683-688页

作者： Maritza Lizeth álvarez-Ainza Humberto González-Ríos Alberto González-León ángel Javier Ojeda-Contreras Ana Isabel Valenzuela-Quintanar Evelia Acedo-Félix Coordinación de Ciencia de los Alimentos de Origen Animal A. C. Hermosillo México Coordinación de Ciencia de los Alimentos de Origen Vegetal Centro de Investigación en Alimentación y Desarrollo A. C. Hermosillo México Coordinación de Ciencia de los Alimentos A. C. Hermosillo México

Bacanora is an artisanal beverage distilled from agave, which is manufactured on a small scale in the Sonora state, México. The aim of this study was to identify the major volatile compounds in 77 artisanal Bacanora beverages by gas chromatography, to determine the samples that comply with the Mexican Standards for Bacanora. The samples were collected in 28 municipalities in the area of origin denomination. It was found that only 55.8% of the samples (43) meet the parameters established in the Official Mexican Standards, whereas 44.2% of the samples (34) do not comply: 3 samples for alcohol content, 8 for acetaldehyde, 1 for esters, 11 for methanol and 17 for higher alcohols. Some of the samples do not comply because of more than one analyzed parameter. The Bacanora samples showed great variability among the sampled regions as well as within the same municipalities (p ≤ 0.05).

关键词： Alcoholic Beverages Bacanora Volatile Compounds Official Mexican Standards

SPECIATION OF NITROGEN COMPOUNDS IN NANosCOPIC FINE AERosOL SAMPLES USING TXRF-NEXAFS

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SPECIATION OF NITROGEN COMPOUNDS IN NANOSCOPIC FINE AEROSOL ...

Diversity and seasonal variation of ground and understory spiders from a tropical mountain cloud forest

全国第六届X射线荧光光谱学术报告会与X射线光谱分析研讨会

作者： J.osán S.rk B.Beckhoff G.Ulm C. Abete R.Fuoco KFKI Atomic Energy Research Institute P.O. Box 49 H-1525 BudapestHungary Physikalisch-Technische Bundesanstalt Berlin Germany CNR-ICCOM Pisa Italy Department of Chemistry and Industrial Chemistry University of Pisa PisaItaly

It is crucial to have analytical methods that enable to measure nitrogen compounds in the aerosol from a short sampling period while retaining the information on the size distribution of the particles. A near edge X-ray absorption fine structure (NEXAFS) investigation in conjunction with total reflection X-ray fluorescence (TXRF) analysis of

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Insect Science 2020年第4期27卷 826-844页

作者： Emmanuel F.Campuzano Guillermo Ibarra-Nunez Salima Machkour-M Rabet Alejandro Moron-Rios Maria Luisa Jimenez Colegio de la Frontera Sur(ECosUR) Unidad TapachulaTapachulaChiapasMexico ECosUR Unidad ChetumalChetumalQuintana RooMexico ECosUR Unidad CampecheCampecheCampecheMexico Centro de Investigaciones Biologicas del Noroeste(CIBNOR) La PazBaja California SurMexico

We made intensive samplings to study the seasonal response of spiders across different forest strata(ground and understory)in a tropical mountain cloud forest from *** sampled spiders from ten plots in six sampling events during the dry and rainy season,to analyze their abundance,structure(distribution of abundance among species),diversity and the response of the five dominant species at each *** demonstrated that seasonal patterns of spider communities differed among strata,revealing a complex spatiotemporal ***,structure,diversity of ground spiders,as well as the responses of four dominant species at this stratum,showed low seasonal *** contrast,a strong seasonal variation was observed for the understory assemblage,with lowest abundance and highest diversity in the rainy season,and different assemblage structures for each *** patterns of each assemblage seem linked to the responses of their dominant *** found high co-occurrence among most of the ground dominant species with similar habitat use and with multivoltine patterns,contrasting with low co-occurrence among most of the understory dominant species with similar habitat use and univoltine *** results showed that the spiders’assemblages of tropical mountain cloud forest(opposed to what is found in temperate and boreal forests)increase their species richness with the height,and that their responses to seasonal change differ between *** programs of these habitats should consider the spatial and temporal variations found here,as a better understanding of their ecological dynamics is required to support their sustainable management.

关键词： community structure El Triunfo Biosphere Reserve interspecific competition Mexico temporal change vertical stratification

The Dynamics of Relation Oat Panicle with Grain Yield by Nitrogen

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American Journal of Plant Sciences 2016年第1期7卷 17-27页

作者： Rubia Diana Mantai José Antonio Gonzalez da Silva Emilio Ghisleni Arenhardt Airam Tereza Zago Romcy Sausen Manuel osório Binello Vidica Bianchi Dionatas Rodrigues da Silva Luiz Michel Bandeira Department of Exact Sciences and Engineering Regional University of the Northwest of Rio Grande do Sul State Ijuí Brazil Department of Agrarian Studies Regional University of the Northwest of Rio Grande do Sul State Ijuí Brazil Department of Crop Plants Federal University of Rio Grande do Sul Porto Alegre Brazil Department of Life Sciences Regional University of the Northwest of Rio Grande do Sul State Ijuí Brazil

The oat panicle components were changed by the forms of nitrogen use influencing productivity. The aim of the study was to determine the direct and indirect effects of oat panicle components on grain yield by N-fertilizer rates in succession systems of high and reduced release of N-residual. The study was conducted in the years 2013 and 2014 in a randomized complete block with four replications in a factorial 3 × 2, for nitrogen rates (30, 60 and 120 kg·ha-1) and oat cultivars (Barbarasul and Brisasul) the soybean/oat and corn/oat systems. The panicle weight and grain per panicle show greater sensitivity to the change of nitrogen rates. Grain yield was favored by the direct effect of harvest index panicle and indirect by grain weight per panicle. In the system soybean/ oat, the grain weight of panicle shows greater efficiency in promoting positive direct effects on grain yield.

关键词： Avena sativa L. Ureia Relation C/N Correlation and Path Analysis

Sexual Function in Pregnant Women in the Public Health System

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Open Journal of Obstetrics and Gynecology 2019年第6期9卷 764-774页

作者： Candice Cezimbra Miranda Amanda Vilaverde Perez Bruno Ribeiro Bossardi Luiza Cabreira Brust Fernanda Santos Grossi Edimárlei Gonsales Valério Janete Vettorazzi Maria Celeste osório Wender PostgraduationProgram in Health Sciences: Gynecology and Obstetrics Universidade Federal do Rio Grande do Sul (UFRGS). Rua Ramiro Barcelos Santa Cecilia Porto Alegre RS Brazil FAMED UFRGS Rua Ramiro Barcelos Santa Cecilia Porto Alegre RS Brazil Department of Gynecology and Obstetrics Faculty of Medicine (FAMED) UFRGS Rua Ramiro Barcelos Santa Cecilia Porto Alegre RS Brazil Service of Obstetrics and Gynecology Hospital de Clínicas de Porto Alegre (HCPA) Rua Ramiro Barcelos Santa Cecília Porto Alegre RS Brazil

Introduction: Pregnancy is a unique situation and involves changes in sexuality. The aim is to evaluate sexual function and satisfaction in pregnant women under prenatal care provided by the public health system. Method: Cross-sectional study with pregnant women receiving ambulatory care in the public health system in the Southern region of Brazil conducted between November 2014 and September 2015. Results: 283 pregnant women were studied. The mean age was 27.7 ± 6.3 years;64% were white and 31.1% were nulliparous. In the total sample, 8.50% were in the first trimester of pregnancy, 37.4% were in the second trimester, and 54.1% were in the third trimester. The rate of global sexual dysfunction (score 26 points) was 55.5%, following the application of The Female Sexual Function Index (FSFI). Sexual dysfunction was significantly more prevalent in the third trimester (62%) compared to the first (33.3%) and second (50.9%) trimesters (p = 0.015). There was a significant difference in all domains, except in the desired domain, according to the trimester. Pregnant women in the third trimester showed significantly lower scores compared to those in the first trimester in the domains with significance. Conclusion: The prevalence of sexual dysfunction among pregnant women in the public system was high. Knowing that more than 50% of the pregnant women presented sexual dysfunction, it is essential to approach sexuality during prenatal care involving the couple.

关键词： Sexual Dysfunction Pregnancy Female Sexual Function Index Sexuality Sexual Function

Detailed characterization of a laboratory magnetized supercritical collisionless shock and of the associated proton energization

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Matter and Radiation at Extremes 2022年第1期7卷 15-28页

作者： W.Yao A.Fazzini S.N.Chen K.Burdonov P.Antici J.B´eard S.Bolaños A.Ciardi R.Diab E.D.Filippov S.Kisyov V.Lelasseux M.Miceli Q.Moreno V.Nastasa S.Orlando S.Pikuz D.C.Popescu G.Revet X.Ribeyre E.d’Humi`eres J.Fuchs LULI–CNRS CEAUPMC Univ Paris 06:Sorbonne Universit´eEcole PolytechniqueInstitut Polytechnique de ParisF-91128 Palaiseau CedexFrance Sorbonne Universit´e Observatoire de ParisUniversit´e PSLCNRSLERMAF-75005 ParisFrance ELI-NP “Horia Hulubei”National Institute for Physics and Nuclear Engineering30 Reactorului StreetRO-077125 Bucharest-MagureleRomania IAP Russian Academy of Sciences603155 Nizhny NovgorodRussia INRS-EMT 1650 Blvd.Lionel-BouletVarennesQuebec J3X 1S2Canada LNCMI UPR 3228CNRS-UGA-UPS-INSAF-31400 ToulouseFrance JIHT Russian Academy of Sciences125412 MoscowRussia Universit`a degli Studi di Palermo Dipartimento di Fisica e Chimica E.Segr`ePiazza del Parlamento 190134 PalermoItaly INAF–osservatorio Astronomico di Palermo PalermoItaly University of Bordeaux Centre Lasers Intenses et ApplicationsCNRSCEAUMR 5107F-33405 TalenceFrance ELI-Beamlines Institute of PhysicsCzech Academy of Sciences5 Kvetna 83525241 Dolni BrezanyCzech Republic NRNU MEPhI 115409 MoscowRussia

Collisionless shocks are ubiquitous in the Universe and are held responsible for the production of nonthermal particles and high-energy *** the absence of particle collisions in the system,theory shows that the interaction of an expanding plasma with a pre-existing electromagnetic structure(as in our case)is able to induce energy dissipation and allow shock *** formation can alternatively take place when two plasmas interact,through microscopic instabilities inducing electromagnetic fields that are able in turn to mediate energy dissipation and shock *** our platform in which we couple a rapidly expanding plasma induced by high-power lasers(JLF/Titan at LLNL and LULI2000)with high-strength magnetic fields,we have investigated the generation of a magnetized collisionless shock and the associated particle *** have characterized the shock as being collisionless and *** report here on measurements of the plasma density and temperature,the electromagnetic field structures,and the particle energization in the experiments,under various conditions of ambient plasma and magnetic *** have also modeled the formation of the shocks using macroscopic hydrodynamic simulations and the associated particle acceleration using kinetic particle-in-cell *** a companion paper to Yao et al.[***.17,1177–1182(2021)],here we show additional results of the experiments and simulations,providing more information to allow their reproduction and to demonstrate the robustness of our interpretation of the proton energization mechanism as being shock surfing acceleration.

关键词： field collision shock

Effect of split applications of urea on protein size distribution, physical dough properties, and baking performance of five experimental bread wheat lines

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Agricultural Sciences 2011年第3期2卷 181-190页

作者： Alma Rosa Islas-Rubio Karla Chávez-Quiroz Francisco Vásquez-Lara Brenda Silva-Espinoza María del Carmen Granados-Nevárez Humberto Gonzalez-Ríos Miguel Camacho-Casas Departamento de Tecnología de Alimentos de Origen Vegetal Centro de Investigación en Alimentación y Desarrollo A.C. Carretera a la Victoria Km 0.6 Hermosillo Sonora México Departamento de Tecnología de Alimentos de Origen Vegetal Centro de Investigación en Alimentación y Desarrollo A.C. Carretera a la Victoria Km 0.6 Hermosillo Sonora México. 83000

Five experimental bread wheat lines (BWL) were grown at the Yaqui Valley Experimental Station in Sonora, México during two consecutive growing cycles. The effect of five nitrogen fertilization (NF) treatments on protein size distribution (PSD), physical dough properties (PDP), and baking performance of the BWL was evaluated. Polymeric and monomeric proteins were evalu-ated by SE-HPLC. PDP were carried out by the National Mixograph and the TA-XT2 Texture Analyzer. Baking performance was evaluated using the straight dough method. Protein content (PC), main protein fractions (glutenins, gliadins, albumins-globulins), and mixograph development time (MDT) were significantly influenced by NF treatment and BWL but not by their interaction. On the other hand, PDP measured by the Kieffer rig, and baking performance were significantly influenced by the main factors (NF and BWL) and their interaction. The amount and timing of fertilizer applied to the BWL modified the PC, PSD, PDP, and bread loaf volume. PDP exhibited a larger variation in comparison to the PSD of glutenins. The split application of 150 kg of urea/ha (50-50-50) to all BWL showed a better loaf volume response than the same amount of urea applied at sowing (150-0-0). The application of 300 kg of urea/ha to all BWL, either at sowing or at three split applications of 100 kg of urea/ha each, resulted in higher flour unextractable polymeric protein (FUPP). On the other hand, the split application of 100-100-100 kg of urea/ha to three of the BWL represented the higher total unextractable polymeric protein (TUPP). Differences on PC and PSD were reflected on differences on PDP and bread loaf volume observed among the BWL.

关键词： Wheat Nitrogen Fertilization Protein Composition Dough Properties