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Mollusk species richness on the rocky shores of the state of Guerrero, Mexico, as Affected by rains and Their Geographical Distribution

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Natural resources 2012年第4期3卷 248-260页

作者： Flores-r.dr.guez Pedro Flores-Garza rafael García-Ibánez sergio Valdés-González Arcadio Violante-González Juan santiago Cortés Enedina Galeana-rebolledo Lizeth Torreblanca-ramírez Carmina Unidad Académica de Ecología Marina Universidad Autónoma de Guerrero Acapulco México Universidad Autónoma de Nuevo León Laboratorio de Acuacultura Facultad de Ciencias Biológicas Ciudad Universitaria San Nicolás de los Garza México

Natural processes in ecosystems shows significant variations in species richness with regular cycles that can be altered by natural or anthropogenic activities;the present research was in order to understand on some of these variations. The objectives were: 1) determine the species richness of rocky intertidal mollusks;2) track their geographical distribution at state level;and 3) determine the changes in species richness as a result of rainfall on an annual cycle. For these purposes it was sampled in March, June, september and December 2005, the sampled area was 20 m2for each collecting site;the sampling unit was a PVC rectangle frame one by two meter per side. The mollusks found within the sampling units were collected, identified and counted. The species distribution was analyzed by sites and regions, considered species richness per season, and the distributional patterns by rainy season historical records. A total of 62 mollusks species were found, its richness associated with substrate stability and wave intensity on each site, Gastropods had the highest species richness. When analyzing the regional distribution and sites, it was found a pattern of species richness roughly constant in the proportion of species with wide distribution (generalists) versus those of restricted spatial representation (specialists). Gastropods had the highest number of species with restricted spatial representation. seasonal rainfall differences did not quantitatively altered on the overall the species of mollusks in the rocky intertidal sampled zone however, in the analysis per Class, Gastropoda indicated changes in species richness influenced by rainfall, which were not observed in Bivalvia and Polyplacophora, suggesting that those changes might depend on adaptive processes or the lack of adaptation of gastropod species to the characteristics of the rocky intertidal habitat.

关键词： rocky shore species richness Geographic Distribution rain Effects Mollusks

Electrochemical Corrosion study in H<sub>2sub>sO<sub>4sub> of NiAl with Cu Additions, Microstructure and Micro-Hardness at room Temperature

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Journal of Minerals and Materials Characterization and Engineering 2022年第3期10卷 225-241页

作者： Jesús M. Colín de la Cruz sergio A. serna Barquera Alvaro Torres-Islas Arturo Molina-Ocampo Edgar Valenzuela José G. González r.dr.guez Universidad Autónoma del Estado de Morelos Facultad de Ciencias Químicas e Ingeniería UAEM-FCQeI. Av. Universidad 1001Colonia Chamilpa Cuernavaca Morelos México Universidad Autónoma del Estado de Morelos Centro de Investigación en Ingeniería y Ciencias Aplicadas UAEM-CIICAp Cuernavaca Morelos México UABC Baja California Sur México

For many years, intermetallic materials promise applications in a wide variety of technology areas. NiAl intermetallic compound is material that exhibits important characteristics such as high corrosion resistance and low density besides its ability to retain strength and stiffness at elevated temperatures. However NiAl intermetallic is too hard, brittle and exhibits very low ductility at room temperature being the reason because this material is not yet available for structural applications. In order to increase the ductility of the NiAl intermetallic compound, the addition of a third alloying element has been proved, nevertheless it is important to determine if such additions decrease or increase the hardness and the corrosion resistance of the alloy. so, the present investigation reports the corrosion performance of the NiAl intermetallic compound modified with Cu, emphasizing the EIs analysis and the relation between physical parameters and the modelling equations used in the Equivalent Electric Circuit. It was found that the addition of Cu promotes the formation of the γ’-Nisub>3sub>Al phase in Cu contents greater than 15 at. %, in addition to a decrease in micro hardness and an increment in the Isub>corrsub> values. In this way, the electrochemical characterization evidenced a high corrosion resistance of these intermetallic alloys.

关键词： NiAl-Cu Corrosion Behavior Electrochemical Impedance spectrum Vickers Micro Hardness Microstructure

Low-Dose Gamma radiation Fields Decrease Cell Viability, Damage DNA,and Increase the Expression of Hsp70 and p53 Proteins in Human Leukocytes

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Mollusks of the rocky Intertidal Zone at Three sites in Oaxaca,Mexico

World Journal of Nuclear science and Technology（核科学与技术国际期刊） 2023年第4期

作者： Jessica Lizbeth sifuentes Padilla David Alejandro García López Consuelo Letechipia de León Hector rene Vega-Carrillo sergio hugo sánchez r.dr.guez

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Open Journal of Marine science 2014年第4期4卷 326-337页

作者： Pedro Flores-r.dr.guez rafael Flores-Garza sergio García-Ibánez Carmina Torreblanca-ramírez Lizeth Galeana-rebolledo Enedina santiago-Cortes Laboratorio de Ecologia Costera y sustentabilidad Unidad Academica de Ecologia MarinaUniversidad Autonoma de GuerreroAcapulcoMexico Doctorado en Ciencias Ambientales Unidad de Ciencias de Desarrollo RegionalUniversidad Autonoma de GuerreroAcapulcoMexico

The community of mollusks at three rocky intertidal zone in Oaxaca, Mexico was analyzed. Two samplings per site were conducted. At each sampling the inspected area was 10 m2. The sampling unit was 1 m2. 5862 specimens were examined. 68 mollusks species were identified. The families better represented in species richness were: FIssUrELLIDAE, MUrICIDAE, LOTIIDAE, MYTILIDAE, CHAMIDAE, IsCHNOCHITONIDAE y CHITONIDAE. The species that had the greatest density were Lottia discors, siphonaria palmata, Lottia acutapex, Chormoytilus palliopunctatus, Brachidontes adamsianus, Chton articulatus e Ischnochiton muscarius. The species with the widest distribution represent 11.76%. With irregular distribution was found in 58.82% of the species. The gastropod Crucibulummonticulus, the bivalve C. palliopunctatus and the polyplacophoran C. articulatus had the greatest size. The value of diversity index was H’ = 4.29 bits/ind. and J’ = 0.72. The mollusks community in the rocky intertidal zone study sites is characterized by small size, because they rarely exceed seventy millimeters. The values of H’ and J’ indicate that the mollusk community in the study area has a high diversity and high uniformity, corresponding to mature and stable communities in a tropical region.

关键词： Intertidal Zone Oaxaca Biodiversity Mollusks

Intraoperative laparoscopic complications for urological cancer procedures

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World Journal of Clinical Cases 2015年第5期3卷 450-456页

作者： sergio Fernández-Pello Montes Ivan Gonzalez r.dr.guez rodrigo Gil Ugarteburu Luis r.dr.guez Villamil Begoa Diaz Mendez Patricio suarez Gil Javier Mosquera Madera Urology Department Cabueñes Hospital33203 GijónAsturiasSpain

AIM: To structure the rate of intraoperative complications that requires an intraoperative or perioperative resolution. METHODs: We perform a literature review of Medline database. The research was focused on intraoperative laparoscopic procedures inside the field of urological oncology. General rate of perioperative complications in laparoscopic urologic surgery is described to be around 12.4%. Most of the manuscripts published do not make differences between pure intraoperative, intraoperative with postoperative consequences and postoperative complications. rEsULTs: We expose a narrative statement of complications, possible solutions and possible preventions for most frequent retroperitoneal and pelvic laparoscopic surgery. We expose the results with the following order: retroperitoneal laparoscopic surgery(radical nephrectomy, partial nephrectomy, nephroureterectomy and adrenalectomy) and pelvic laparoscopic surgery(radical prostatectomy and radical cystectomy).CONCLUsION: Intraoperative complications vary from different series. More scheduled reports should be done in order to better understand the real rates of complications.

关键词： Intraoperative complications Laparoscopy surgical complication Urology Cancer

Air pollution and heart failure: relationship with the ejection fraction

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World Journal of Cardiology 2013年第3期5卷 49-53页

作者： Alberto Dominguez-r.dr.guez Javier Abreu-Afonso sergio r.dr.guez ruben A Juarez-Prera Eduardo Arroyo-Ucar Yenny Gonzalez Pedro Abreu-Gonzalez Pablo Avanzas Department of Cardiology Hospital Universitario de Canarias Universidad Europea de Canarias Facultad de Ciencias de la Salud Instituto Universitario de Tecnologías Biomédicas Department of Applied Physics Universidad de Valencia Center for Atmospheric research Izaa AEMET-CSIC Department of Physiology Universidad de la Laguna Department of Cardiology Hospital Universitario Central de Asturias

AIM: To study whether the concentrations of particulate matter in ambient air are associated with hospitaladmission due to heart failure in patients with heart failure with preserved ejection fraction and reduced ejection fraction. METHODs: We studied 353 consecutive patients admitted into a tertiary care hospital with a diagnosis of heart failure. Patients with ejection fraction of ≥ 45% were classified as having heart failure with preserved ejection fraction and those with an ejection fraction of re classified as having heart failure with reduced ejection fraction. We determined the average concentrations of different sizes of particulate matter (rations of gaseous pollutants (carbon monoxide, sulphur dioxide, nitrogen dioxide and ozone) from 1 d up to 7 d prior to admission. rEsULTs: The heart failure with preserved ejection fraction population was exposed to higher nitrogen dioxide concentrations compared to the heart failure with reduced ejection fraction population (12.95 ± 8.22 μg/m 3 vs 4.50 ± 2.34 μg/m 3 , P riate analysis showed that nitrogen dioxide was a significant predictor of heart failure with preserved ejection fraction (odds ratio ranging from (1.403, 95%CI: 1.003-2.007, P = 0.04) to (1.669, 95%CI: 1.043-2.671, P = 0.03). CONCLUsION: This study demonstrates that shortterm nitrogen dioxide exposure is independently associated with admission in the heart failure with preserved ejection fraction population.

关键词： Air pollution Heart failure Preserved ejection fraction reduced ejection fraction Nitrogen dioxide

Brain-derived neurotrophic factor plasma levels and premature cognitive impairment/dementia in type 2 diabetes

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World Journal of Diabetes 2016年第20期7卷 615-620页

作者： Blanca Murillo Ortíz Joel ramírez Emiliano Edna ramos-r.dr.guez sandra Martínez-Garza Hilda Macías-Cervantes sergio solorio-Meza Texar Alfonso Pereyra-Nobara Unidad de Investigación en Epidemiología Clínica Unidad Médica de Alta Especialidad No. 1 BajioInstituto Mexicano del Seguro Social Departamento de Ciencias Médicas División Ciencias de la SaludUniversidad de Guanajuato

AIM To assess the relationship of brain-derived neurotrophic factor(BDNF) with cognitive impairment in patients with type 2 diabetes. METHODs The study included 40 patients with diabetes mellitus type 2(DM2), 37 patients with chronic kidney disease in hem dialysis hemodialysis therapy(HD) and 40 healthy subjects. BDNF in serum was quantified by ELIsA. The Folstein Mini-Mental state Examination was used to evaluate cognitive *** The patients with DM2 and the patients in HD were categorized into two groups, with cognitive impairment and without cognitive impairment. The levels of BDNF showed significant differences between patients with DM2(43.78 ± 9.05 vs 31.55 ± 10.24, P = 0.005). There were no differences between patients in HD(11.39 ± 8.87 vs 11.11 ± 10.64 P = 0.77); interestingly, ferritin levels were higher in patients with cognitive impairment(1564 ± 1335 vs 664 ± 484 P = 0.001). The comparison of BDNF values, using a Kruskal Wallis test, between patients with DM2, in HD and healthy controls showed statistical differences(P sION Low levels of BDNF are associated with cognitive impairment in patients with DM2. The decrease of BDNF occurs early and progressively in patients in HD.

关键词： Diabetes mellitus type 2 Hemodialysis Brain-derived neurotrophic factor Folstein mini-mental Premature cognitive impairment

spatial-Temporal Analysis of Territorial Transformations in the state of sinaloa Mexico Using Geographic Information systems

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Agricultural sciences 2017年第2期8卷 171-182页

作者： Wenseslao Plata rocha Gabriela Corrales Barraza Geovanna Guadalupe Hinojoza Castro sergio Alberto Monjardin Armenta Jose Carlos Beltrán González Héctor Enrique r.dr.guez Lozoya Faculty of Earth and space sciences Autonomous University of Sinaloa Culiacán Mexico

In the last years the whole planet has been suffering remarkable changes, including the land use and cover, and that this is one of the many components of the global change. The present study has as main objective described the changes of land use and cover occurred in the state of sinaloa during the period 1976-2011. For this, we used 4 maps of land use and vegetation of 1976, 1993, 2007 and 2011. This analysis was carried out applying statistical techniques and Geographic Information systems (GIs). The methodology is based on the analysis of the cross-tabulation matrix or change matrix, from which it is possible to obtain indicators of change for each time interval analyzed (1976-1993, 1993-2007 and 2007-2011), as well as the gain and loss of each of the 10 categories contained in the maps. To raise the level of details in the analysis were studied the annual changes considering for this the intensity of the gains and annual losses. Also we elaborated graphs and maps that allow us describing and identifying the magnitude and spatial distribution of the changes. The results obtained show a deterioration in the rainforest, important changes in the irrigated and seasonal agriculture and the spatial exchanges in the forest areas, as well as a considerable increase in the urban areas.

关键词： Change Use Intensity GIs Mexico

Chlorophyll Concentration and Morphological Diversity in Corn Lines at Different Vegetative stages

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American Journal of Plant sciences 2016年第7期7卷 1067-1076页

作者： Mariano Mendoza Elos Gilberto r.dr.guez Pérez Francisco Cervantes Ortíz Luis Patricio Guevara Acevedo Enrique Andrio Enríquez Ma. Del Carmen Ojeda Zacarías Isabel Presa Figuereo sergio Alfredo r.dr.guez Herrera José Antonio rangel Lucio José Guadalupe rivera reyes Division of Graduate studies and research Institute Technologic of Roque Guanajuato Mexico University Autonomous Agrarian of Nuevo León Monterrey México University Autonomous Agrarian Antonio Narro Saltillo México

The objective of this study was to assess the chlorophyll content of corn lines at different vegetative stages and the diversity between them. The study was conducted in the experimental field of the roque Institute of Technology (ITr) located in roque, Celaya, Guanajuato, Mexico. We used 32 corn lines from CIMMYT and four lines from the breeding program of the ITr. The evaluation was conducted in the spring-summer cycle of 2014 at two planting dates. We used a completely randomized block design with three replications. The experimental unit consisted of two rows of five linear meters with a distance of 0.75 meters between rows. Chlorophyll was measured at six different stages: V6, VT, r3, r4, r5 and MF. The agronomic variables recorded were: PH, CH, LAC, LBC, FF, MF, PM, CC, CL, DC, rC, Kr and GY. The results of the analysis of variance showed significant differences between lines, dates and their interaction. On average, 18 lines were found with chlorophyll concentrations above 51 sPAD units in the two environments. This indicated that these materials had a high potential for field performance. Using cluster analysis UPGMA method, we identified seven groups for chlorophyll and eight groups for agronomic characteristics for a breeding program. The groups were associated to the homogeneous characteristics of each variable.

关键词： Chlorophyll Content Phenological stages Clusters and Corn Lines