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Journal of Environmental Sciences 2010年第7期22卷 1080-1085页

作者： ulrico J.lópez-chuken Scott D.Young Division of Environmental Sciences School of ChemistryUniversidad Autónoma de Nuevo León Division of Agricultural & Environmental Sciences School of Biosciencesthe University of Nottingham

A controlled hydroponic experiment was undertaken to investigate Cd uptake in relation to the activity of Cd species in solution other than the free ion （Cd^2＋） by maintaining a constant Cd^2＋ activity under variable SO4^2- and Cl^- concentrations exposed to maize （Zea mays vat. Cameron） plants. The objectives of these experiments were：（1） to distinguish and quantify the different uptake rates of free and inorganic-complexed Cd from nutrient solution, and （2） to model the uptake of Cd by maize with a Biotic ligand Model （BlM） in a system which facilitates the close examination of root characteristics. Results of the current experiments suggest that, in addition to the free ion, CdSO4^0 complexes are important factors in determining Cd uptake in nutrient solution by maize plants. Higher nominal SO4^2- concentrations in solution generally resulted in a greater Cd accumulation by maize plants than predicted by the Cd^2＋ activity. A better integration of the complete dataset for the 3 harvest times （6, 9 and 11 days after treatment） was achieved by including consideration of both the duration of Cd exposure and especially the root surface area to express Cd uptake. Similarly, the fit of the BlM was also improved when taking into account exposure time and expressing uptake in terms of root morphological parameters.

关键词： free ion activity model biotic ligand model root surface area Cd complexation metal exposure time hydroponics plant uptake

Study of Trace Ions in Wet Deposition of an Industrial Site in Monterrey’s Metropolitan Area, Mexico

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Open Journal of Ecology 2016年第1期6卷 1-12页

作者： Evangelina Ramírez-lara Rosa María Cerón-Bretón Julia Griselda Cerón-Bretón ulrico lópez-chuken Jonathan Kahl Facultad de Ciencias Químicas Universidad Autónoma de Nuevo León San Nicolás de los Garza México Facultad de Química Universidad Autónoma del Carmen Ciudad del Carmen México Department of Mathematical Science University of Wisconsin-Milwaukee Milwaukee USA

The chemistry of rainwater has been subject to numerous investigations during the last two decades due to the increase of environmental problems caused by the acid deposition. The present study focuses on one aspect of air pollution, the chemical composition of wet deposition of an industrial zone. The sampling period was from March to December 2009. The station was located on the roof of the Chemistry School at the University of Nuevo león, an area in the north of Monterrey where the majority of pollution is generated. Twenty-five wet precipitation samples were collected with an automatic sampler and analyzed for pH, ions (, , Cl-, Ca2+, Mg2+, Na+, K+) and conductivity. The results show that the average pH is higher than 5.6;the characteristics of the rainwater studied are of alkaline nature due to the values of pH found;there is an evident anthropogenic source contributing to the alkaline of rain water. In order to find possible association between ions and consequently the possible sources of pollutants correlation study was applied using the program SPSS v.12. Good correlations were found between ions and along with Ca2+ and Mg2+. The local extraction industry and surrounding aerosols might be causing of alkaline rain which may be due to the neutralization effect of particulate matter. This study represents a continuation of the studies of rainwater chemistry in the Northeast of Mexico.

关键词： Wet Deposition Air Quality Monterrey Air Pollution

Evaluation of Water Quality Index in lerma River Upper Basin

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Journal of Environmental Protection 2013年第7期4卷 98-103页

作者： Icela D. Barceló-Quintal Mónica l. Salazar-Peláez Julisa García-Albortante Eloisa Domínguez-Mariani ulrico J. lópez-chuken Sergio Gómez-Salazar área de Química y Fisicoquímica Ambiental División de Ciencia Básicas e Ingeniería Universidad Autónoma Metropolitana Unidad Azcapotzalco Mexico City Mexico Centro Universitario de Ciencias Exactas e Ingenierías Universidad de Guadalajara Guadalajara Mexico Facultad de Ciencias Químicas Universidad Autónoma de Nuevo León San Nicolás de los Garza Mexico

The lerma River Upper Basin is located between Almoloya del Rio shallow lakes and Atlacomulco Municipality in the State of Mexico;is a natural resource essential to human activities in its surroundings and serves as a source of electricity and drinking water for Mexico City. However, this river is threatened by over-exploitation of its aquifers, disappearance of many of its wellsprings and uncontrolled discharges of wastewater from all sorts. Thus, the aim of this work was to evaluate the water quality in the Upper lerma River Basin using WQI proposed by the NSF and compare these results with those obtained by the National Water Commission of Mexico (CNA). WQI was calculated using seven parameters: dissolved oxygen, pH, DOB5, temperature change, total phosphates, nitrates, and total solids obtained in four different sampling campaigns carried out in 2005, 2006 and 2012. The results showed that water quality in the Upper lerma River is bad, mainly associated with high levels of BOD5, nitrates and phosphates found. The results obtained with WQI yielded the same diagnosis that the studies carried out by the CNA, in which water quality was unacceptable. It is worth noting that there is a significant water quality deterioration in the Upper lerma River Basin with the course of the years, because in 2012 were observed the lower index values regarding 2005 and 2006, so it is imperative to implement measures to restore and preserve the water quality of this important river.

关键词： Water Quality Index lerma River Upper Basin BOD5 Nitrates Phosphates

Microbial Degradation of Organophosphate Pesticides： A Review

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Pedosphere 2018年第2期28卷 190-208页

作者： Shardendu KUMAR Garima KAUSHIK Mohd Ashraf DAR Surendra NIMESH ulrico Javier lOpez-chuken Juan Francisco VIllARREAl-CHIU Department of Environmental Science School of Earth Sciences Central University of Rajasthan Ajmer 305817 (India) Department of Biotechnology School of Life Sciences Central University of Rajasthan Ajmer 305817 (India) laboratorio de InvestigaciSn en Ciencias Ambientales Facultad de Cieneias Quimicas Universidad AutSnoma de Nuevo León Nuevo LeSn 66455 (Mexico) laboratorio de Biotecnologla Facultad de Ciencias Qulmicas Universidad AutSnoma de Nuevo LeSn Nuevo Ledn 66455 (Mexico)

Pesticides have become an inevitable part of the modern environment as they are widely used in agriculture,household,and public health sectors and,hence,are extensively distributed throughout most ***,organophosphate pesticides are the most commercially favored group of pesticides,with large application areas all over the *** on their fate,these organophosphorus compounds may become bioavailable for microbial *** microbes,such as Aspergillus,Pseudomonas,Chlorella,and Arthrobacter,are capable of coupling a variety of physical and biochemical mechanisms for the degradation of organophosphate pesticides,including adsorption,hydrolysis of P–O alkyl and aryl bonds,photodegradation,and enzymatic ***,such as esterase,diisopropyl fluorophosphatase,phosphotriesterase,somanase,parathion hydrolase,and paraoxonase,have been isolated from microbes to study and understand the catabolic pathways involved in the biotransformation of these xenobiotic *** review highlights various aspects of biodegradation of organophosphate pesticides along with biological and molecular characterization of some organophosphate pesticide-degrading bacteria.

关键词： biodegradation enzymes insecticide metabolic pathways pesticide-degrading bacteria organophosphorus compound xenobiotics

Water Quality Assessment of a Tropical Mexican lake Using Multivariate Statistical Techniques

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Journal of Environmental Protection 2015年第3期6卷 215-224页

作者： Jessica Badillo-Camacho Eire Reynaga-Delgado Isela Barcelo-Quintal Pedro F.Zarate del Valle ulrico J.lopez-chuken Eulogio Orozco-Guareno Jorge Israel AlvarezBobadilla Sergio Gomez-Salazar Departamento de Quimica Universidad de Guadalajara-Centro Universitario de Ciencias Exactas e IngenieriasGuadalajaraMexico Departamento de Farmacobiologia Universidad de Guadalajara-Centro Universitario de Ciencias Exactas e IngenieriasGuadalajaraMexico Departamento de Ciencias Basicas Universidad Autonoma MetropolitanaUnidad AzcapotzalcoMexico D.F.Mexico Facultad de Ciencias Quimicas Universidad Autonoma de Nuevo LeonSan Nicolas de los GarzaMexico Departamento de Ingenieria Quimica Universidad de Guadalajara-Centro Universitario de Ciencias Exactas e IngenieriasGuadalajaraMexico

Water quality of Mexican tropical lake Chapala was assessed through multivariate statistical techniques, cluster analysis (CA) and principal component analysis (PCA) at ten different monitoring sites for ten physicochemical variables and six metals. This study evaluated and interpreted complex water quality data sets and apportioned of pollution sources to get better information about water quality. From descriptive statistics results, the highest concentrations of metals occurred during the dry season, and this trend was explained by the fact that an unusual rainy event occurred during the month of February 2009 and brought metals into the lake by runoffs from nearby mountains. According to international criteria for water consumption by aquatic organisms [USEPA], only Zn concentration values were below these criteria whereas the values of Ni, Pb, Cd and Fe were above the corresponding values set in these criteria (Ni: 52 μg·l-1, Pb: 2.5 μg·l-1, Cd: 0.25 μg·l-1, and Fe: 1000 μg·l-1). The correlations were observed by PCA, which were used to classify the samples by CA, based on the PCA scores. Seven significant cluster groups of sampling locations—(sites 4 and 5), (sites 3 and 9), (site 7), (site 10), (sites 2 and 6), (site 8) and (site 1)— were detected on the basis of similarity of their water quality. The results revealed that the stress exerted on the lake caused by waste sources follows the order: domestic > agricultural > industrial.

关键词： Multivariate Statistical Analysis toxic Metals Water Quality lake Pollution

left atrial thrombosis in an anticoagulated patient after bioprosthetic valve replacement:Report of a case

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World Journal of Clinical Cases 2014年第1期2卷 20-23页

作者： Gian Marco Rosa Antonello Parodi ulrico Dorighi Federico Carbone Franois Mach Alessandra Quercioli Fabrizio Montecucco Nicolas Vuilleumier Manrico Balbi Claudio Brunelli Clinic of Cardiovascular Diseases Internal Medicine Department San Martino Hospital and University of Genoa 16143 Genoa Italy Division of Cardiology Department of Internal Medicine Foundation for Medical researches University of Geneva 1211 Geneva Switzerland the First Medical Clinic Laboratory of Phagocyte Physiopathology and Inflammation Department of Internal Medicine University of Genoa 16143 Genoa Italy Division of laboratory Medicine Department of Genetics and Laboratory Medicine Geneva University Hospitals 1211 Geneva Switzerland

We present the case of a 74 year old woman suffering from severe mitral valve incompetence and rapid atrial fibrillation. After an appropriate vitamin K antagonist(VKA) therapy, the patient underwent mitral valve replacement by bioprosthesis. Then, the patient was rehospitalized for jaundice. Suspecting hepatotoxicity, VKA was discontinued and fondaparinux was started. During this treatment, the patient developed a symptomatic atrial thrombus. After exclusion of a hepatic disease, VKA was re-established with hemodynamic and liver enzymes normalization and atrial thrombus resolution. Caution has to be used when considering fondaparinux as an alternative strategy to VKA in patients with multiple thrombotic risk factors.

关键词： Mitral valve Thrombus Prosthetic valve Atrium Hepatotoxicity