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Contamination of Water for Domestic Use and Human Consumption by Heavy Metals Derived from Mining Activity in Parral, Chihuahua, Mexico

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Journal of Environmental Science and Engineering(A) 2012年第3期1卷 286-294页

作者： Luis Miguel Rodriguez Ever torres Luis Saenz Maria del Carmen Avitia Guillermo Rodriguez Eduardo Herrera Carmen Julia Navarro Guillermo gonzalez Luis Lozoya Damaris Acosta Technological Institute of Parral Parral Chihuahua 33850 Mexico Research Center for Advanced Materials （CIMA V） Chihuahua 31109 Mexico

Research was done with the objective of evaluating the quality of water supplied to the potable water system in Hidalgo Del Parral, which comes from two main supply sources： wells from ＂Valle del Verano＂, which provide water to the east side of the city, and the Water Treatment Plant, which receives water from different mines and supplies the west side of the city. When this plant is overcome on its capacity of treatment, a part of the water from the mines is fed directly to the northwest part of the city. The metals lead （Pb）, chromium （Cr）, cadmium （Cd）, zinc （Zn）, and arsenic （As） were analyzed by atomic absorption （AA） technique, based on the United States Environmental Protection Agency （EPA） Method 7000B （Revision 2, February 2007）. The digestion process was done according to the guidelines established in Method NMX-AA-051-SCFI-2001, Analysis of Water-Determination of Metals by Atomic Absorption, developed by the National Standardization Technical Committee for Environmental Protection （Mexico）. The samples were collected from the following points： 13 wells and 2 re-pumping stations of ＂Valle del Verano＂, the inlet and outlet of the Water Treatment Plant, and domestic faucets. The east side of the city, supplied by the wells of ＂Valle del Verano＂, is metal-pollution free. The water that comes from the mines contains high concentrations of As, Zn, Cd and Pb, with levels that can get to 0.12, 32.6, 0.26 and 3.5 mg/L, respectively. This water pollution generated by mining can be concluded from the high levels found in the domestic samples in which, for several points, the concentrations exceed the parameters set by the current guideline. According to the results, it is vital to set a plan of remediation for the water that comes from the mines, because there is a great risk for health in the consumotion of this water.

关键词： Heavy metals mining water contamination.

Ammonium Thiosulfate Ecological Viable Alternative to Replace Sodium Cyanide in Gold and Silver Dissolution Ores

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Journal of Environmental Science and Engineering(A) 2016年第5期5卷 223-229页

作者： Maria del Carmen Hernandez Maria del Carmen Avitia Heriberto Pena Irma Leticia gonzalez Nancy Veronica torres Abdiel Rosaldo Felix[ Luis Miguel Rodriguez Laura Bibiana Hernandez Department of Chemical and Biochemical Engineering Technological Institute of Parral Chihuahua 33850 Mexico Department of Economic Administrative Department Technological Institute of Parral Chihuahua 33850 Mexico Department of Industrial Engineering Technological Institute of Parral Chihuahua 33850 Mexico Engineering and Independent Consultant Palma Triangular 108 San Jose de Pozo Bravo Aguascalientes 20126 Mexico

The southern region of the state of Chihuahua is mining by origin, as this has been proved ghost towns of Minas Nuevas, it is also called Villa Escobedo, Emerald and Blue. Minerals are nonrenewable resources. There are only reserves and waste deposited in tailings ponds of low-rade precious metals （gold and silver）. A conventional method for recovering gold and silver ore is low-grade cyanidation and the solvent consider toxic and highly dangerous for the flora, fauna, humans and the environment. The mechanism of cyanide poisoning is inhibition of cytochrome oxidase--an enzyme needed for cell respiration. Without compromising efficiency, sensitivity and cost of the process, the toxic solvent is replaced by a less aggressive one, which helps the environment, public and occupational health. （NH4）2S203 has no appreciable damage to conservative amounts, is a selective aqueous solvent for leaching gold and silver, easy to get and manipulate. This work is done in the Technological Institute of Parral in a low-grade ore from the southern region of the state of Chihuahua. This document has been enriched presented in the IMEC 2014, with the increase of series Ⅴ and Ⅵ.

关键词： Leaching cyanide ammonium thiosulfate.

Chemical Structure of TiO Organometallic Particles Obtained by Plasma

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Advances in Nanoparticles 2013年第3期2卷 229-235页

作者： Ma. Guadalupe Olayo Francisco González-Salgado Guillermo J. Cruz Lidia Ma. Gómez Genoveva García-Rosales Maribel gonzalez-torres Osvaldo G. Lopez-Gracia Departamento de Física Instituto Nacional de Investigaciones Nucleares Ocoyoacac México Departamento de Física Instituto Nacional de Investigaciones Nucleares Ocoyoacac México Departamento de Posgrado Instituto Tecnológico de Toluca Metepec México Departamento de Física Instituto Nacional de Investigaciones Nucleares Ocoyoacac México Posgrado en Ciencia de Materiales Facultad de Química Universidad Autónoma del Estado de México Toluca México Departamento de Física Instituto Nacional de Investigaciones Nucleares Ocoyoacac México Posgrado en Ciencias Químicas Facultad de Química Universidad Autónoma del Estado de México Toluca México Departamento de Posgrado Instituto Tecnológico de Toluca Metepec México

This work presents a study about the chemical structure of titanium oxide (TiO) particles synthesized by plasmas using titanium tetrapropoxide, Ti(-O-CH2-CH2-CH3)4. In plasmas, practically all chemical bonds are susceptible to participate in the reactions producing different results than those obtained by the traditional chemical routes. The particles obtained this way are semispheres and fibers grouped in random and layered structures in the 120-500 nm interval and mean diameter of 86.4 nm (fibers) and 308.6 nm (semispheres). The analysis of the resulting TiO structure was performed by IR and XPS finding that the main chemical state of Ti in these conditions was O2-Ti-O2 (Ti surrounded by O) which is part of the precursor structure, however, in O, the main chemical state was Ti-O-Ti formed with the rupture of the pre- cursor Ti-O-C bonds. These last bonds reduce the conjugation between the structure of both elements, O2-Ti-O2 and Ti-O-Ti, to produce organometallic compounds. Other chemical states appeared showing consecutive dehydrogenation steps during the synthesis with the formation of multiple bonds as a consequence of the continuous collisions in the plasma. These results allow us to follow the chemical reactions promoted by this kind of plasmas to produce TiO nanoparticles which are essentially conformed of intensive dehydrogenation.

关键词： TiO Particles Plasma Degradation XPS TTP

Fe-Mn nodules associated with hydrocarbon seeps： A new discovery in the Gulf of Cadiz （eastern central Atlantic）

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Episodes 2007年第3期30卷 187-196页

作者： FJ．Gonzdlez L．Somoza R．Lunar J.Marffnez-Frias J.A．MarffnRubi T.torres J．E．oniz V.Diaz-del-Rio MarineGeologyDv GeologicalSurveyofSpain（IGME）．C／RiosRosas2328003MadridSpain．E-mail：fj-gonzalez@igme．es Departamento de Cristalografla Y Mineralogia UniversidadComplutensedeMadridUCM．C／JoseAntonio-Novais2CiudadUniversitaria28040MadridSpain． Centro de AstrobiologiaCSIC／INTA．29006Torrej6ndeArdozMadrid Spain． Laboratorio de Estratigraffa Biomolecular（ETSIM／UPM）．C／RfosRosas21 28003MadridSpain． Centro Oceanografico de Mailaga InstitutoEspafiol de OceanograffaIEO．Apdo．28529640Fuengirola（Mailaga）Spain

The Gulf of Cadiz is situated geologically at the Gibraltar Arc, the westernmost arc of the Alpine- Himalayan orogenic belt. Based on extensive previous studies that include swath bathymetry, multi-channel and very high-resolution seismic reflection, gravime- try, magnetism, heat flow probes, and underwater photography surveys, more than 500 polymetallic nodules were collected at water depths ranging from 850 to 1000 m, associated with hydrocarbon-derived carbonate chimneys, slabs, and crusts. Nodules show a wide range of sizes, densities, weights and mor- phologies. Nodules are composed of multiple milli- metre-thick layers of Fe and Mn oxyhydroxides sur- rounding a nucleus composed of Early-Middle Mio- cene plastic marls, which were expulsed from underly- ing units by fluid venting. Nodules show a high mean abundance of Fe （39.03%）, moderate Mn （5.84%）,

关键词：碳氢化合物渗出物加的斯海湾大西洋铁锰

High-Resolution Esophageal Manometry in Teenagers with Esophageal Atresia

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Open Journal of Epidemiology 2020年第1期10卷 81-89页

作者： Cecilia Zubiri Rosa Ramos Cecilia Curvale Raúl Matanó Paula Borobia Anabella Zosi Verónica Garrido julieta Hernández Lucía Gutierrez Luciana Guzmán María Cristina Arregui Marina Prozzi Sandro Miculan Viviana Bernedo Maximiliano Fernández Rivas Cristina Lorenzo Florencia Recalde Verónica Valdiviezo Darío Fajre Cintia Antonioli Mariana Allende Claudia Losada Teresita gonzalez Department of Gastroenterology at Hospital de Niños Sor María Ludovica La Plata Buenos Aires Argentina Department of Gastroenterology at Hospital de Alta Complejidad El Cruce Florencio Varela Buenos Aires Argentina Posadas Hospital Buenos Aires Argentina Department of Nutrition at Hospital de Niños Sor María Ludovica La Plata Buenos Aires Argentina Department of Surgery at Hospital de Niños Sor María Ludovica La Plata Buenos Aires Argentina Department of Otorhinolaryngology at Hospital de Niños Sor María Ludovica La Plata Buenos Aires Argentina Department of Pneumonology at Hospital de Niños Sor María Ludovica La Plata Buenos Aires Argentina

Introduction: Children with surgically repaired esophageal atresia (EA) show esophageal dysmotility. Due to the performance of high-resolution manometry (HRM), three motility alteration patterns have been described, which allowed to know the segmental alterations. Objective: To describe the esophageal motility patterns found through HRM in teenagers with EA and to relate these with the associated esophageal pathology and its severity. Materials and Method: Ten teenagers were included with no history of esophageal blockage or dilations in the last six months, who were orally fed and asymptomatic. Through performance of HRM, we found surgical and endoscopic history, as well as of esophageal biopsies and pH monitoring. Results: We found the following patterns: aperistalsis, pressurization and distal contraction. 70% showed distal contraction, and 100% of esophageal endoscopies and biopsies were normal. 57% of the esophageal pH monitoring analyzed was pathologic. In the pressurization and aperistalsis groups, we observed severe esophagitis and requirement of Nissen antireflux procedure in 100% of the cases. Esophageal pH monitoring analyzed was 100% pathologic. Conclusion: We described the esophageal segmental alterations in teenagers with atresia by means of HRM. The distal contraction group showed better development, without severe esophagitis or requirement of antireflux procedure. Therefore, by performing an HRM in teenagers with EA, we could predict the future esophageal behavior, according to the peristaltic pattern, since there are significant differences among the groups in study.

关键词： High-Resolution Manometry Esophageal Atresia Teenagers

What is the prognosis of emphysematous pyelonephritis associated with extended-spectrum beta-lactamases producing microorganisms?

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Asian Journal of Urology 2022年第2期9卷 146-151页

作者： JoséIván Robles-torres Marco Alberto Ocaña-Munguía JoséGustavo Arrambide-Herrera Adrián Mauricio Martínez-Fernández Rodrigo Romero-Mata Lauro Salvador Gómez-Guerra Urology Department Hospital Universitario"Dr.Jose´Eleuterio Gonza´lez"Universidad Auto´noma de Nuevo LeonMonterreyNuevo LeonMexico

Objective:To describe the microbiological characteristics in emphysematous pyelonephritis(EPN),demonstrate the frequency of extended-spectrum beta-lactamase(ESBL)microorganisms,and determine if these microorganisms are associated with the prognosis of patients with ***:We conducted a retrospective study in patients with a diagnosis of EPN in a tertiary care hospital of the northeast region of Mexico during the period from January 2011 to January *** variables were analyzed to determine association with the presence of ESBL-producing *** significance was set with p<***:A total of 63 patients were included;55(87.3%)of them were females,with a median age of 55(interquartile range:45-65)*** management was indicated in 38.1%;42.9%were treated with ureteral stent;12.7%with open or percutaneous drainage;15.8%with early nephrectomy;and 9.5%with delayed *** mortality was 13(20.6%)cases;23(36.5%)cases required admission to the intensive care *** most frequent microorganism isolated was Escherichia coli(n=34,53.9%).ESBL microorganisms were found in 31.7%of the *** significant association of ESBL was found with admission to the intensive care unit,or with increased ***:To our knowledge,this is the first study that evaluates ESBL microorganisms as a prognostic factor in *** factors associated with a poor prognosis in patients with EPN have been *** microbiological factors,specifically ESBL-producing bacteria,do not seem to influence in the prognosis of these patients.

关键词： Emphysematous pyelonephritis Extended spectrum betalactamase Mortality Intensive care unit admission

Green Synthesis of Bimetallic Nanoparticles From Prosopis juliflora(Sw)DC.,and Its Effect Against Cotton Mealybug,Phenacoccus solenopsis(Hemiptera:Pseudococcidae)

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Phyton-International Journal of Experimental Botany 2019年第3期88卷 269-275页

作者： V.Mendez-Trujillo B.Valdez-Salas M.Carrillo-Beltran M.A.Curiel-Alvarez O.Tzintzun-Camacho C.Ceceña-Duran D.gonzalez-Mendoza Facultad de Medicina de la Universidad Autónoma de Baja California Dr.Humberto Torres Sanginés S/NCentro Cívico21000MexicaliBaja CaliforniaMéxico Instituto de Ingeniería de la Universidad Autónoma de Baja California Calle de la Normal S/N y Boulevard Benito Juárez21100MexicaliBaja CaliforniaMéxico Instituto de Ciencias Agrícolas de la Universidad Autónoma de Baja California(ICA-UABC).Carretera a Delta S/N C.P.21705 Ejido Nuevo LeónBaja CaliforniaMéxico

Phenacoccus solenopsis has been recognized as an aggressively invasive species on cotton plants in different *** study was conducted to investigate the effect of green synthesized Cu/Zn-nanoparticles using aqueous leaf extract of Prosopis juliflora(mezquite)against *** scanning electron microscope(SEM)showed bimetallic nanoparticles of Cu/Zn-NPs with spherical shape with varying size of 74.33 nm to 59.46 *** than 30%mortality of *** was observed with Cu/Zn-nanoparticles(100 ppm)at 96 hours after *** mortality of *** was recorded with Cu/Zn solution(100 ppm)and aqueous *** *** results of the viability test for Cu/Zn-nanoparticles of *** showed a significant reduction of the cell viability by 50%in insect exposed to Cu/*** studies about nanotoxicity of Cu/Zn-NPs of *** are needed to reveal the mechanism of toxicity this phytonanoparticles in ***.

关键词： Photosynthesis biocontrol cotton mealybug nanoinsecticide

A Novel and Functional Artificial Bruch’s Membrane Made of Poly (ε-Caprolactone)/Gelatin for Retinal Pigment Epithelium Restoration

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Advances in Bioscience and Biotechnology 2024年第8期15卷 443-461页

作者： López Edith Silva-Bermudez Phaedra gonzalez-Salinas Roberto Velasquillo Cristina torres-Romero Abigail López-Colomé Ana María Pérez Armando Gina Prado-Prone Edgar Ramos-Martínez Iván Ramos-Martínez Quiroz-Mercado Hugo Hernández-Zimbrón Luis Fernando Instituto de Fisiologa Celular Universidad Nacional Autnoma de Mxico Ciudad de Mxico City Mxico Unidad de Ingeniería de Tejidos Terapia Celular y Medicina Regenerativa Instituto Nacional de Rehabilitación Luis Guiller-mo Ibarra Ibarra Ciudad de México México Departamento de Investigacin Asociacin Para Evitar la Ceguera Ciudad de Mxico Mxico Subdireccin de Investigacin Tecnolgica Instituto Nacional de Rehabilitacin Luis Guillermo Ibarra Ibarra Ciudad de Mxico Mxico Departamento de Biologa Celular y Tisular Facultad de Medicina Universidad Nacional Autnoma de Mxico Ciudad de Mxico Mxico Escuela de Ciencias Universidad Autnoma Benito Jurez de Oaxaca Oaxaca Mxico Departamento de Medicina y Zootecnia de Cerdos Facultad de Medicina Veterinaria y Zootecnia Universidad Nacional utnoma de Mxico Mxico Laboratorio de Investigacion Interdisciplinaria rea de Optometria Escuela Nacional de Estudios Superiores Unidad Len Universidad Nacional Autnoma de Mxico Len Guanajuato Mxico Laboratorio Nacional de ptica de la Visin-Centro de Investigaciones en ptica Len Guanajuato Mxico

Purpose: The primary aim of this paper is to design, create, and improve functional and artificial Bruch’s membranes (BM) using bioengineering techniques, which can be applied in the treatment of maculopathies by supporting the growth and maintenance of retinal pigment epithelium (RPE) cells, thereby potentially enabling subretinal implantation in patients. Methods: We fabricated by electrospinning ultrathin 3D nanofibrous membranes from Polycaprolactone (PCL), and different concentrations of gelatin (5%, 15% and 30%). ARPE-19 cells were seeded onto these artificial membranes. MTT assays were performed in order to evaluate ARPE-19 cell viability and cytotoxicity. IF assays were realized to observe the ARPE-19 cells onto each membrane. Ultrastructure of the modified Bruch’s membrane and ARPE-19 morphology after 25 days of culture were studied with transmission and scanning electron microscopy. To evaluate expression changes in markers of ARPE-19 (RPE65 and ZO-1) qRT-PCR assays were realized. Data from three independent experiments were pooled and expressed as the mean SD. A confidence level of P 0.05 was considered to be statistically significant. Results ARPE-19 cells grew on PCL/Gelatin membranes mainly in PCL/30% gelatin combination, which had not cytotoxic effect. RPE65/cytokeratin-18/ and actin-positive ARPE-19 cells formed a correctly orientated monolayer of polygonal cells with morphological polarity. The apical cell surfaces exhibited abundant protruding microfolds. Moreover, zones of polygonal border look as if ARPE-19 cells fused among, suggesting the presence of tight junctions. The expression of RPE65 and ZO-1 was unchanged. Conclusions: PCL/30% Gelatine membranes may imitate the natural BM to such extent that they support RPE-cells and exhibited RPE-like morphology. The engineering of a human RPE monolayer with these artificial BM, emulating the in vivo retina, arouse their potential subretinal implantation in patients with wet age-related macular degene

关键词： Artificial Bruch’s Membrane Electrospinning ARPE-19 Cells Age-Related Macular Degeneration

192例糖尿病肺结核患者的不典型X线影像:一项比较性研究

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国际结核病与肺部疾病杂志 2001年第3期 101-106页

作者： C. Perez-Guzman A. torres-Cruz H. Villarreal-Velarde M. A. Salazar-Lezama M. H. Vargas 安燕生 Instituto Nacional de Enfermedades Respiratorias Departamento de Neumologia Hospital General CMN La Raza Instituto Mexicano del Seguro Social Instituto Nacional de Enfermedades Respiratorias Hospital General "Dr. Manuel Gea gonzalez" Instituto Nacional de Enfermedades Respiratorias Hospital de Pediatria CMN Siglo XXI Instituto Mexicano del Seguro Social Mexico DF Mexico

背景:糖尿病肺结核患者产生异常X线影像的比较性研究。目的:对大量糖尿病肺结核患者的X线影像进行评价。设计:复习住院的糖尿病肺结核患者(TBDM组,n=192)的X线片,与对照组单纯肺结核病患者(TB组,n=130)进行比较。结果:两组的结核病... 详细信息

背景:糖尿病肺结核患者产生异常X线影像的比较性研究。目的:对大量糖尿病肺结核患者的X线影像进行评价。设计:复习住院的糖尿病肺结核患者(TBDM组,n=192)的X线片,与对照组单纯肺结核病患者(TB组,n=130)进行比较。结果:两组的结核病演变时间相似(～2年)。所观察到的统计学差异如下:TBDM组病人年龄较高(为51.3±0.9岁,TB组为44.9±1.8岁,均数±均数标准误),上肺野发生率降低(17％比56％),下肺野病变发生率(19％比7％)及上肺野加下肺野病变率之和(82％比59％)升高。TBMD组发生空洞的病人多(82％比59％),并且多发生于下肺野(29％比3％)。多发空洞常见于TBDM组病人(25％比2％)。TBDM组病人白细胞总数偏低(8836.7±219.5比10013.1±345.2/mm^3),主要由于非淋巴细胞的白细胞数低(6815.8±221.8比8095.7±321.9/mm^3)。多元logistic回归分析显示,糖尿病是造成下肺野病灶和空洞最重要的因素。结论:本研究以大量糖尿病肺结核患者资料证实这些病人的胸部X线影像与典型的表现显著不同。临床医生必须牢记这点以避免误诊。

关键词：空洞胸部X线比较性研究糖尿病肺结核放射学 X线片