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Natural and Anthropogenic Influence in Water Quality:The Case of Linares City,NE Mexico

Journal of Water Resource and Protection 2013年第11期5卷 1066-1075页

作者： Liliana Lizarraga-Mendiola Jose Navar alberto blanco-pinon Ma.Del Refugio Gonzalez-Sandoval Hector De-Leon-Gomez Area Academica de Ingenieria Universidad Autonoma del Estado de Hidalgo.Mineral de la ReformaHidalgoMexico Centro Interdisciplinario de Investigacion para el Desarrollo Integral Regional Instituto Politecnico Nacional.DurangoDurangoMexico Area Academica de Ciencias de la Tierra y Materiales Universidad Autonoma del Estado de Hidalgo.Mineral de la ReformaHidalgoMexico Instituto de Ingenieria Civil Universidad Autonoma de Nuevo LeonMonterreyNuevo LeonMexico

The aim of this research paper was to identify whether the water quality had been influenced either by the natural environment or by anthropogenic activities or both in the municipality of Linares, the second largest city of the State of Nuevo Leon, NE Mexico. The superficial water (Pablillo River) and the groundwater quality (from a fractured and a porous aquifers hydraulically interconnected) were determined by comparing their chemical composition with maximum permissible limits for water consumption and irrigation use. A hydrogeochemical modeling was performed to identify the distribution of aqueous species responsible for the presence of some dissolved or precipitated mineral species, as well as an identification of geochemical factors responsible of superficial and groundwater quality. A canonical correspondence analysis was allowed to determine if the natural environment and/or anthropogenic activities were responsible for water quality. The parameters analysed in both aquifers, as well as in the Pablillo River, were total solids, suspended solids, nitrate, and chloride;barium and mercury were present in both aquifers. As a natural influence, the predominant mineral species are as following: under-saturated anhydrite (porous aquifer), over-saturated aragonite, calcite, dolomite, and gypsum (both aquifers and Pablillo River), barite and whiterite (only in fractured aquifer). The geochemical factors responsible for natural contamination were rock dominance (fractured aquifer), and evaporation dominance (porous aquifer, Pablillo River). On the other hand, anthropogenic activities such as changes in soil use and the presence of point (old municipal landfill, pig farms, barite deposit), and diffuse (agricultural areas, septic tanks and latrines) pollution sources had influence in the presence of contaminants such as total and fecal coliforms, nitrates, chlorides, mercury and barium. Several control and remediation strategies should be taken into account to prevent

关键词： Fractured Aquifer Pablillo River Pollution Sources Porous Aquifer Water Quality

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Fossil Stomatocysts in Upper Cretaceous Sedimentary Pyrite from Central Mexico

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International Journal of Geosciences 2014年第2期5卷 214-221页

作者： Carlos Castaneda-Posadas alberto blanco-pinon Juan Hernandez-Avila Silvia P.Ambrocio-Cruz Liliana Lizarraga-Mendiola Susana A.Angeles-Trigueros Laboratorio de Paleontologia-Escuela de Biologia Benemerita Universidad Autonoma de PueblaPueblaMexico Area Academica de Ciencias de la Tierra y Materiales Universidad Autonoma del Estado de HidalgoHidalgoMexico Area Academica de Ingenieria Universidad Autonoma del Estado de HidalgoHidalgoMexico Instituto de Geologia Universidad Autonoma de San Luis PotosiSan Luis PotosiMexico

In this paper six fossil forms of Chrysophycean stomatocysts are described. The material was collected from sedimentary pyrite embedded in well-laminated organic-rich limestone of the Upper Cretaceous Agua Nueva Formation at the locality of Xilitla, Central Mexico. The stomatocysts are represented by two spherical specimens with smooth surfaces lacking of ornamentation, three ovoid forms with rugose textures, one of them exposing presence of pore without collar, and one spherical specimen showing rugose texture and the presence of two short and rounded projections. The specimens here described showed affinity with some stomatocysts morphotypes described for brackish and fresh water, but not for known marine specimens. The presence of these microfossils in the Agua Nueva Formation represents the first formal description of fossil stomatocysts in Upper Cretaceous sedimentary pyrite in Mexico. The occurrence of both micro (planktonic foraminifera, calcispheres, radiolarians) and macrobiota (ammonites, inoceramid bivalves and fishes) and the presence of the specimens in sedimentary pyrite suggest that the stomatocysts were preserved under oxygen-deficiency conditions in a low energy environment. This event could have occurred in open marine waters in the Tampico-Misantla basin (Central Mexico) during the late Cenomanian throughout the early Turonian.

关键词： Fossil Stomatocysts Upper Cretaceous Agua Nueva Formation Mexico Sedimentary Pyrite

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Contamination Potential of an Urban Mine Tailings Deposit in Central Mexico—A Preliminary Estimation

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International Journal of Geosciences 2014年第3期5卷 296-312页

作者： Liliana Lizarraga-Mendiola Diana Elizabeth Angeles-Chavez alberto blanco-pinon Marius Ramirez-Cardona Francisco Javier Olguin-Coca Maria del Refugio Gonzalez-Sandoval Academic Area of Engineering Institute of Basic Sciences and EngineeringAutonomous University of the State of HidalgoPachucaMexico Academic Area of Earth and Materials Sciences Institute of Basic Sciences and EngineeringAutonomous University of the State of HidalgoPachucaMexico

This study consisted of a geochemical analysis of the Dos Carlos tailings’ deposit located in the Mining District of Pachuca-Real del Monte in the state of Hidalgo, Central Mexico. The goal of the study was to determine the potential effects of this deposit on the environment and health of the population of the metropolitan area of Pachuca. Sampling was conducted from the top to the base of two raised sections at opposite ends of the deposit, and macroscopic features (profiles A and B) of these deposits were evaluated. Subsequently, mineralogical analyses of the collected samples were performed using X-ray diffraction and physico-chemical analysis of the leachates. The results were compared with the maximum permissible limits established by different national and international standards for drinking water and hazardous waste. In addition, geochemical modeling was conducted using PHREEQC to calculate the distribution of aqueous species, ionic activities and saturation indices.(For more information, please refer to the PDF.)

关键词： Contamination Dos Carlos Tailings Mining District Pachuca-Real del Monte

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Clinical features of alcoholic hepatitis in latinos and caucasians: A single center experience

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World Journal of Gastroenterology 2017年第40期23卷 7274-7282页

作者： Rogelio pinon-Gutierrez Blythe Durbin-Johnson Charles H Halsted Valentina Medici Division of Gastroenterology and Hepatology Department of Internal Medicine University of California Davis Division of Biostatistics University of California Davis Department of Public Health Sciences

AIM To study differences of presentation, management, and prognosis of alcoholic hepatitis in Latinos compared to Caucasians. METHODS We retrospectively screened 876 charts of Caucasian and Latino patients who were evaluated at University of California Davis Medical Center between 1/1/2002-12/31/2014 with the diagnosis of alcoholic liver disease. We identified and collected data on 137 Caucasians and 64 Latinos who met criteria for alcoholic hepatitis, including chronic history of heavy alcohol use, at least one episode of jaundice with bilirubin ≥ 3.0 orcoagulopathy, new onset of liver decompensation or acute liver decompensation in known cirrhosis within 12 wk of last drink. RESULTS The mean age at presentation of alcoholic hepatitis was not significantly different between Latinos and Caucasians. There was significant lower rate of overall substance abuse in Caucasians compared to Latinos and Latinos had a higher rate of methamphetamine abuse(12.5% vs 0.7%) compared to Caucasians. Latinos had a higher mean number of hospitalizations(5.3 ± 5.6 vs 2.7 ± 2.7, P = 0.001) and mean Emergency Department visits(9.5 ± 10.8 vs 4.5 ± 4.1, P = 0.017) for alcohol related issues and complications compared to Caucasians. There was significantly higher rate of complications of portal hypertension including gastrointestinal bleeding(79.7% vs 45.3%, P < 0.001), spontaneous bacterial peritonitis(26.6% vs 9.5%, P = 0.003), and encephalopathy(81.2% vs 55.5%, P = 0.001) in Latinos compared to *** Latinos have significant higher rates of utilization of acute care services for manifestations alcoholic hepatitis and complications suggesting poor access to outpatient care.

关键词： Alcoholic hepatitis Latino Hispanic Caucasian Alcoholic liver disease

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Microbiological Contamination of Bed Linen and Staff Uniforms in a Hospital

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Advances in Microbiology 2013年第7期3卷 515-519页

作者： Anthony pinon Jessica Gachet Virginie Alexandre Sandra Decherf Michèle Vialette Unité de Sécurité Microbiologique Institut Pasteur de Lille Lille France

Hospital linen is clearly recognized as a potential reservoir for microorganisms and could be a vector of disease transmission. The aim of this study was to isolate, count and identify fungi and bacteria from different kinds of clean and dirty linen in a hospital. Microbiological samples have been collected on clean bed linen (n = 200), dirty bed linen (n = 192) and staff uniforms (n = 192) by using contact plates. 55% of samples from clean bed linen were contaminated before contact with the patient, with a mean count of 3 cfu/25 cm2 (range: 1-117 cfu) when contaminated. Virtually all samples from dirty bed linen carried microorganisms, with a mean count of 23 cfu/25 cm2 (range 1-191 cfu). In addition, staff hospital uniforms showed the highest contamination rates in the study, with an average of 45 cfu/25 cm2 (range: 1-218 cfu). Microbial species were mostly bacteria commonly found in the environment or on human skin, such as staphylococci or micrococci. Nevertheless, 57% of the identified species may be opportunistic pathogens for humans, representing a risk for people with a deficient or weakened immune system, especially in cases of superinfection. Since contamination of linen seems to occur after washing, actively antimicrobial textiles would represent a valuable measure to prevent textiles from being a vehicle for transfer of microorganisms.

关键词： Linen Bed Sheets White Coat Contamination Hospital Acquired Infections

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