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Use of two-surfactants mixtures to attain specific HLB values for assisted TPH-diesel biodegradation

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Journal of Environmental Sciences 2004年第6期16卷 950-956页

作者： luis G. torres Neftalí Rojas Rosario Iturbe Instituto de Ingeniería Universidad Nacional Autó noma de México Coordinación de Ingeniería Ambiental Grupo Saneamiento de Suelos y Acuíferos Apartado Postal 70-472 Coyoacán 04510 México D.F. Mexico

In a surfactant assisted biodegradation process, the choice of surfactant(s) is of crucial importance. The question is: does the type of surfactant(i.e. chemical family) affect the biodegradation process at fixed hidrophillic-lypofillic balance(HLB) values? Microcosm assessments were developed using contaminated soil, with around of 5000 mg/kg of hydrocarbons as TPH-diesel. Mixtures of three nonionic surfactants were employed to get a wide range of specific HLB values. Tween20 and Span20 were mixed in the appropriate proportions to get HLB values between 8.6 and 16.7. Tween/Span60 mixtures reached HLB values between 4.7 and 14.9. Finally, Tween/Span80 combinations yielded HLB values between 4.3 and 15. TPH-diesel biodegradation was measured at the beginning, and after 8 weeks, as well as the FCU/gr soil, as a measure of microorganisms′ development during the biodegradation period. A second aim of this work was to assess the use of guar gum as a biodegradation enhancer instead of synthetic products. The conclusions of this work are that surfactant chemical family, and not only the HLB value clearly affects the assisted biodegradation rate. Surfactant's synergism was clearly observed. Regarding the use of guar gum, no biodegradation enhancement was observed for the three assessed concentrations, i.e., 2, 20, and 200 mg/kg, respectively. On the contrary, TPH-diesel removal was lower as the gum concentration increased. It is quite possible that guar gum was used as a microbial substrate.

关键词： aged soils enhanced bioremediation HLB mixtures Tween Span surfactants

Hepatitis C virus clearance and less liver damage in patients with high cholesterol, low-density lipoprotein cholesterol and APOE ε4 allele

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World Journal of Gastroenterology 2019年第38期25卷 5826-5837页

作者： Karina Gonzalez-Aldaco Sonia Roman Rafael torres-Valadez Claudia Ojeda-Granados luis A torres-Reyes Arturo Panduro Department of Molecular Biology in Medicine Civil Hospital of Guadalajara "Fray Antonio Alcalde" and Health Sciences Center University of Guadalajara

BACKGROUND Cholesterol is related to improvements in the rate of sustained virological response and a robust immune response against the hepatitis C virus(HCV).APOE gene polymorphisms regulate cholesterol levels modifying the course of the HCV *** relationship between cholesterol,APOE alleles,and the outcome of HCV infection has not been evaluated in the admixed population of *** To investigate the role of APOE-ε2,-ε3,and-ε4 alleles and the metabolic profile in the outcome of HCV *** A total of 299 treatment-na?ve HCV patients were included in this retrospective *** were stratified in chronic hepatitis C(CHC)(n=206)and spontaneous clearance(SC)(n=93).A clinical record was *** tests were assessed by dry chemistry *** genotypes were determined using a Real-Time polymerase chain reaction *** Total cholesterol,low-density lipoprotein cholesterol(LDL-c),triglycerides,and hypercholesterolemia were higher in SC than CHC patients as well as the frequency of the APOEε4 allele(12.4%vs 7.3%).SC patients were overweight(54.8%).Theε4 allele was associated with SC(OR=0.55,95%CI:0.31-0.98,P=0.042)and mild fibrosis(F1-F2)in CHC patients(OR 0.091,95%CI 0.01-0.75,P=0.020).LDL-c≥101.5 mg/dL(OR=0.20,95%CI:0.10-0.41,P<0.001)and BMI≥26.6 kg/m2(OR=0.37,95%CI:0.18-0.76,P<0.001)were associated with SC status;while ALT≥50.5 IU/L was negatively associated(OR=5.67,95%CI:2.69-11.97,P<0.001).CONCLUSION In SC patients,the APOEε4 allele and LDL-c conferred a protective effect in the course of the HCV infection in the context of excess body weight.

关键词： Liver damage Body mass index Spontaneous hepatitis C virus clearance Low-density lipoprotein Cholesterol

A novel and stretchable carbon-nanotube/Ni@TiO_(2):W photocatalytic composite for the complete removal of diclofenac drug from the drinking water

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Journal of Environmental Sciences 2023年第4期126卷 575-589页

作者： Ernesto Valadez-Renteria Rafael Perez-Gonzalez Christian Gomez-Solis luis Armando Diaz-torres Armando Encinas Jorge Oliva Vicente Rodriguez-Gonzalez Consejo Nacional de Ciencia y Tecnología-División de Materiales Avanzados Instituto Potosino de Investigación Científica y TecnológicaSan Luis Potosí78216México División de Ciencias e Ingenierías Universidad de GuanajuatoLeón 37150México Grupo de Espectroscopia de Materiales Avanzados y Nanoestructurados(GEMANA) Centro de Investigaciones enópticaA.C.Lomas Del CampestreLeón 37150México

We present the structural,morphological and photocatalytic properties of stretchable composites made with carbon nanotubes (CNTs),silicon rubber and Ni@TiO_(2):W nanoparticles(TiWNi NPs) with average size of 37±2 *** images showed that the TiWNi NPs decorated the surface of the CNT fibers,which are oriented in a preferential *** NPs presented a mixture of anatase/rutile phases with cubic *** performance of the TiWNi powders and stretchable composites was evaluated for the photocatalytic degradation of diclofenac (DCF) anti-inflammatory drug under ultraviolet-visible *** results revealed that the maximum DCF degradation percentages were 34.6%,91.9%,97.1%,98.5%and 100%for the CNT composite (stretched at 0%),TiWNi powders,CNT+TiWNi(stretched at 0%),CNT+TiWNi (stretched at 50%) and CNT+TiWNi (stretched at 100%),***,stretching the CNT+TiWNi composites was a good strategy to enhance the DCF degradation percentage from 97.1%to 100%,since stretching created additional defects (oxygen vacancies) that acted as electron sink,delaying the electron-hole recombination,and favors the DCF ***/absorbance measurements confirmed the presence of such ***,the reactive oxygen species (ROS) were determined by the scavenger’s experiments and found that the main ROS were the·OH and O_(2)-radicals,which attacked the DCF molecules,causing their *** results of this investigation confirmed that the stretchable CNT/TiWNi-based composites are a viable alternative to remove pharmaceutical contaminants from water and can be manually separated from the decontaminated water,which is unviable using photocatalytic powders.

关键词： Diclofenac Pharmaceutical contaminant TiO_(2) Carbon nanotubes Stretchable composite Photocatalysis

A decrease of docosahexaenoic acid in testes of mice fed a high-fat diet is associated with impaired sperm acrosome reaction and fertility

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Asian Journal of Andrology 2021年第3期23卷 306-313页

作者： Julio Bunay Luz-Maria Gallardo Jorge luis torres-Fuentes M Veronica Aguirre-Arias Renan Orellana Nestor Sepulveda Ricardo D Moreno Physiology Department Faculty of Biological SciencesPontificia Universidad Cat6lica de Chile(PUC)Santiago 8331150Chile Department of Chemistry and Biological Sciences Health Sciences FacultyUniversidad Bernardo 0 HigginsSantiago 8370854Chile Center of Excellence in Biotechnology of Reproduction Universidad de la FronteraTemuco 4780000Chile.

Obesity is a major worldwide health problem that is related to most chronic diseases,including male *** to its wide impact on health,mechanisms underlying obesity-related infertility remain *** this study,we report that mice fed a high-fat diet(HFD)for over 2 months showed reduced fertility rates and increased germ cell apoptosis,seminiferous tubule degeneration,and decreased intratesticular estradiol(E2)and E2-to-testosterone ***,we also detected a decrease in testicular fatty acid levels,behenic acid(C22:0),and docosahexaenoic acid(DHA,22:6n-3),which may be related to the production of dysfunctional ***,we did not detect any changes in the frequency of seminiferous tubule stages,sperm count,or rate of in vitro ***,there was an increase in spontaneous and progesterone-induced acrosomal exocytosis(acrosome reaction)in spermatozoa from HFD-fed *** data suggest that a decrease in E2 and fatty acid levels influences spermatogenesis and some steps of acrosome biogenesis that will have consequences for ***,our results add new evidence about the adverse effect of obesity in male reproduction and suggest that the acrosomal reaction can also be affected under this condition.

关键词： cholesterol estradiol fat acid testis testosterone

Role of microRNAs in alcohol-induced liver disorders and non-alcoholic fatty liver disease

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World Journal of Gastroenterology 2018年第36期24卷 4104-4118页

作者： Jorge-luis torres Ignacio Novo-Veleiro Laura Manzanedo Lucía Alvela-Suárez Ronald Macías Francisco-Javier Laso Miguel Marcos Department of Internal Medicine University Hospital of SalamancaInstitute of Biomedical Research of Salamanca-IBSAL Spanish Working Group on Alcohol and Alcoholism Spanish Society of Internal Medicine Department of Internal Medicine University Hospital of Santiago de Compostela Department of Internal Medicine HM Rosaleda HospitalSantiago de Compostela Department of Medicine Faculty of MedicineUniversity of Salamanca

MicroRNAs(miRNAs) are small non-coding RNAs that regulate multiple physiological and pathological functions through the modulation of gene expression at the post-transcriptional level. Accumulating evidence has established a role for miRNAs in the development and pathogenesis of liver disease. Specifically, a large number of studies have assessed the role of miRNAsin alcoholic liver disease(ALD) and non-alcoholic fatty liver disease(NAFLD), two diseases that share common underlying mechanisms and pathological characteristics. The purpose of the current review is to summarize and update the body of literature investigating the role of miRNAs in liver disease. In addition, the potential use of miRNAs as biomarkers and/or therapeutic targets is discussed. Among all miRNAs analyzed, miR-34 a, miR-122 and miR-155 are most involved in the pathogenesis of NAFLD. Of note, these three miRNAs have also been implicated in ALD, reinforcing a common disease mechanism between these two entities and the pleiotropic effects of specific miRNAs. Currently, no single miRNA or panel of miRNAs has been identified for the detection of, or staging of ALD or NAFLD. While promising results have been shown in murine models, no therapeutic based-miRNA agents have been developed for use in humans with liver disease.

关键词： Alcohol use disorder Alcoholic liver disease Non-alcoholic fatty liver disease Steatosis Obesity miRNA Biomarkers

Zinc bioleaching from an iron concentrate using Acidithiobacillus ferrooxidans strain from Hercules Mine of Coahuila,Mexico

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International Journal of Minerals,Metallurgy and Materials 2011年第5期18卷 523-526页

作者： Diola Marina Nunez-Ramirez Aquiles Solis-Soto JavierLopez-Miranda Javier Lopez-Miranda Benito Pereyra-Alfere Mirtam Rutlaga-Qumones luis Medina- torres Hiram Medrano-Roldan Food and Biotechnology Postgraduate Unit Institute of Technology of Durango Durango 34080 Mexico Institute of Biotechnology Autonomous University ofNuevo Le6n Monterrey N.L. 66451 Mexico Department of Chemical Engineering Faculty of Chemistry Autonomous National University of Mexico Mexico City 04510 Mexico

The iron concentrate from Hercules Mine of Coahuila,Mexico,which mainly contained pyrite and pyrrhotite,was treated by the bioleaching process using native strain Acidithiobacillus ferrooxidans （***） to determine the ability of these bacteria on the leaching of *** native bacteria were isolated from the iron concentrate of the *** bioleaching experiments were carried out in shake flasks to analyze the effects of pH values,pulp density,and the ferrous sulfate concentration on the bioleaching *** results obtained by microbial kinetic analyses for the evaluation of some aspects of zinc leaching show that the native bacteria ***,which is enriched with a 9K Silverman medium under the optimum conditions of pH 2.0,20 g/L pulp density,and 40 g/L FeSO4,increases the zinc extraction considerably observed by monitoring during15 d,i.e.,the zinc concentration has a decrease of about 95% in the iron concentrate.

关键词： pyrite pyrrhotite bioleaching zinc

Optimization of Micromechanical Cleavage Technique of Natural Graphite by Chemical Treatment

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Graphene 2014年第1期3卷 1-5页

作者： luis torres luis Gomez Armas Antonio Carlos Seabra Centro de Ciências Naturais e Humanas Universidade Federal do ABC Sao Paulo Brazil Grupo de óptica Micro e Nanofabricao de Dispositivos (GOMNDI) Universidade Federal do Pampa Rio Grande do Sul Brazil Laboratório de Sistemas Integráveis do Departamento de Engenharia de Sistemas Eletronicos da Escola Politécnica da USP (LSI-PSI/EPUSP) Sao Paulo Brazil

In this work,we report a method to improve the efficiency of the micromechanical cleavage technique to obtain few-layers graphene samples, from natural graphite flakes, which were previously submitted to two chemical treatment times with H2SO4(17 and 25 hours). After the chemical treatment times, Raman spectroscopy reveals a hydrogenation of the few-layer graphene samples, which were obtained from the treated graphite flakes. To analyze the hydrogenation of the samples, the G and 2D bands of the Raman spectra of the treated and un-treated samples were analyzed and compared, as well as the I(2D)/I(G) ratio, revealing a p-doping on the treated samples when compared with the untreated samples. Our studies could be of great importance to obtain larger and greater amount of few-layer graphene samples.

关键词： Graphene Micromechanical Cleavage Raman Spectroscopy Chemical Treatment

Directional derivative-based method for quasi-stationary voltage support analysis of single-infeed VSC-HVDC units

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High Voltage 2020年第5期5卷 511-522页

作者： Arcadio Perilla Jose luis Rueda torres Elyas Rakhshani Roni Irnawan Filipe Faria da Silva Mart van der Meijden Claus Leth Bak Alex Alefragkis Anna Lindefelt Electrical Sustainable Energy Department Delft University of TechnologyMekelweg 42628 CDDelftThe Netherlands 2Department of Energy TechnologyAalborg UniversityPontoppidanstraede 1119220AalborgDenmark 3TenneT TSO B.VArnhemThe Netherlands 4EnerginetFredericiaDenmark

This study presents an investigation of the impact of the quasi-stationary voltage support provided by a voltage source converter(VSC)connected to a single point of a power *** on the directional derivative concept,an analytical method is developed to quantify the sensitivities of the AC bus voltage with respect to the VSC reactive power control *** on a real case study,it is shown that the method applies to VSC units that are part of VSC-HVDC systems,which can operate in a point-to-point or multi-terminal ***-domain simulations are performed to verify the findings from the application of the analytical method on a reduced size power system.

关键词： stationary method system.

Characterization of Polyurethane Nanocomposites for Flame Retardant Applications

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Journal of Chemistry and Chemical Engineering 2018年第2期12卷 60-73页

作者： Mena María Eugenia torres luis Adolfo Estrada Rodolfo Department of Physics and Mathematics University Iberoamericana Mexico CityProlongación Paseo de Reforma#880Lomas de Santa FeMexico City01219México Desarrollos y Acabados en Poliuretano S.A.de C.V. León37545México Department of Engineering University Iberoamericana Leon37238México

In recent years,polymer nanocomposites have attracted extensive attention in materials science because they often exhibit a field of different properties from those of their counterpart polymer micro-composites whose matrices contain the same inorganic *** novel polyurethane nanocomposite to reduce toxic gases was designed to improve the possibility to resolve several industrial and environmental problems after combustion as intoxication by *** to this,stoichiometry of rigid polyurethane foam was based on nonmetallic nanoparticles for fireproof *** the other hand,we realized synthesis and characterization for the novel polymer,Fourier Transform Infrared(FT-IR)spectroscopy and X-ray scattering were applied to collect information on the nanometer-scale physical structure of the polyurethane ***,scanning electron microscopy(SEM)was used to understand the internal nanostructure before and after combustion,as well as the gas chromatography coupled system with thermal desorption analysis(GC/MSD),to identify the chemical compositions and compounds resulted by the combustion gases generated of the polyurethane nanocomposites foams that can produce *** addition,the mechanical and flammability properties of rigid polyurethane were evaluated according to international standard test methods of burning of polymer for example using test ASTM *** to this,polymer nanocomposites for flammability,not only improves the fireproof properties,but can also improve others properties as can be mechanical and thermal stability providing it the potential to bring true applications to materials to take advantage of the synergies in the polymer *** on this evidence,nanopolyurethane could be a new and functional polymer for construction,automotive,or textile industries.

关键词： Nanocomposite polyurethane flame retardant(FR) nanocharacterization industrial applications