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Continuous-Flow Removal of Arsenic in Drinking Water by Filtering down through Fe₃O₄@SiO₂ Magnetic Composite

Journal of Water Resource and Protection 2016年第5期8卷 619-630页

作者： virginia montero-campos Allen Puente-Urbina Centro de Investigación y de Servicios Químicos y Microbiológicos (CEQIATEC) Escuela de Química Tecnológico de Costa Rica Cartago Costa Rica

Natural contamination of world groundwater supplies with arsenic of volcanic origin has become a complicated and growing problem given current shortage of water. Maintenance cost of treatments that are based on ion exchange and reverse osmosis is considered high, in addition to the high production of sludge with such methods. On the other hand, efficiency of treatments employing coagulation/filtration is usually relative, depending on the method of application. Currently, emerging treatments that use nanotechnology are gaining relevance, due to their high efficiency and low cost. These methods are highly selective, with minimum generation of toxic wastes, as long as particle release into the environment is kept under control to avoid health risks. The present study developed filters with magnetic nanoparticles of Fe3O4 (magnetite) supported on porous silica (Fe3O4@SiO2) at a mass ratio of 2:1. The nanoparticles were synthetized by co-precipitation of Fe(II) and Fe(III) using NH4OH(ac) under inert atmosphere. Average sizes of 15 nm were obtained, measured by means of Transmission Electronic Microscopy (TEM) and characterized by X-ray Powder Diffraction (XRD);the magnetic power was qualitatively determined. The efficiency of the composite material (Fe3O4@SiO2) was determined in a prototype laboratory with a height of 60 cm and a diameter of 5 cm, assembled with five filters of the composite material, with 1 g each filter. The filters were wrapped in resistant water-porous fabric to favor continuous flow at a ratio of 0.015 L/min. The test was performed with arsenic solutions at (43.7 ± 2.1 μg/L), similar to the amount present in water supplies currently treated in Costa Rica. The removal was completed in 7 minutes with 0 N.T.U and less than 10 μg/L arsenic concentration (maximum limit allowed in Costa Rica), quantified by Atomic Absorption Spectrometry with Hy

关键词： Magnetite Drinking Water Arsenic Nanotoxicology

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Culture and Molecular Identification of <i>Helicobacter pylori</i>in Drinking Water from Areas of High and Low Incidence of Gastric Cancer in Costa Rica

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Open Journal of Medical Microbiology 2014年第4期4卷 261-269页

作者： virginia montero campos Alejandro Hernández Soto Jorge Camacho Sandoval Instituto Tecnológico de Costa Rica Research & Chemical and Microbiology Services Center-CEQIATEC Cartago Costa Rica Instituto Tecnológico de Costa Rica Biotechnology Research Center Cartago Costa Rica Doctorate in Natural Sciences for Development DOCINADE Cartago Costa Rica

Background: Most patients infected with Helicobacter pylori show no clinical symptoms. Nonetheless, approximately 10% to 20% of these patients will develop peptic ulcers and 1% will develop gastric cancer. The International Agency for Cancer Research has classified Helicobacter pylori as a Group 1 carcinogen. Materials and Methods: Drinking water samples from 20 cantons situated in areas of low and high incidence of gastric cancer in Costa Rica were analyzed. Water samples were concentrated and the nitrocellulose filter was cultivated for later molecular identification of Helicobacter pylori using the glmM marker. The tumor necrosis factor-alpha inducing protein (Tipalpha TNF-α) was used as a pathogenicity marker of the strains found followed by the sequencing of two products. Information on water management by aqueduct operators was collected in order to establish statistical relationships. Results: A total of 112 water samples were analyzed. Successful cultivation and molecular identification using the glmM marker was achieved in 39% of samples from areas of high incidence and in 7.5% of samples from areas of low incidence. Two glmM gene PCR products were sequenced and confirmed as true positives. Conclusions: The highest prevalence rate of Helicobacter pylori was found in water from areas with a high incidence of gastric cancer. Additionally, significant statistical correlations were established among environmental conditions, drinking water management and incidence of gastric cancer.

关键词： Helicobacter pylori Cancer Gastric Drinking Water glmM Marker

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Quantitative Detection of <i>Helicobacter pylori</i>by Real Time PCR in Drinking Water—Environmental and Public Health Risk Significance

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Open Journal of Medical Microbiology 2015年第3期5卷 118-127页

作者： virginia montero-campos Shirley Arias-Cordero Benedicto Valdés-Rodríguez Monserrat Jarquín-Cordero Research & Chemical and Microbiology Services Center—CEQIATEC School of Chemistry Instituto Tecnológico de Costa Rica Cartago Costa Rica Biotechnology Research Center School of Biology Instituto Tecnológico de Costa Rica Cartago Costa Rica Water Laboratory Services Physicochemical University of Chiriqui Chiriqui City Panama

Helicobacter pylori (H. pylori) is bacteria considered to be present in half of the population and it is a public health problem worldwide. Most patients infected with H. pylori show no clinical symptoms;nonetheless, approximately 10% to 20% of these patients will develop peptic ulcers and 1% will develop gastric cancer. The International Agency for Research on Cancer has classified H. pylori as a Group 1 carcinogen, recognized as the only bacteria capable of producing cancer. Samples of drinking water (n = 44) from aqueducts with chlorination treatment in selected areas with high prevalence of gastric cancer were analyzed in Costa Rica. Samples of drinking water from Panamá (n = 44) from aqueducts supplying untreated water for human consumption in the province of Chiriquí were also analyzed. The molecular marker of H. pylori, glmM, was used, and to optimize the Real Time PCR (qPCR) technique, annealing temperature, concentration of primers and probe were standardized;also, by analyzing different standard curves, the best reaction conditions that allowed detecting and quantifying the gene were determined. The LightCycler® 480 II (LC480II) equipment from Roche Diagnostics GmbH was used, as well as the Absolute Quantification Analysis by means of the Second Derivative Maximum Method. In the case of the samples from Costa Rica, it was determined that 79.5% were positive for H. pylori;removing outlier high average, quantification of bacteria was determined in 3.6 × 103 copies/100 mL. For Panamá it was determined that 86% of the samples were found positive for the presence of H. pylori;removing outlier high average quantification of bacteria was determined at 3.3 × 102 copies/100 mL. The difference in values between the aqueducts in both countries revealed an environmental distribution of the bacteria of epidemiological interest in each case.

关键词： Helicobacter pylori Drinking Water Real Time PCR (qPCR) Chlorination Treatment

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Embodying Deeply Held Values in Education:Seeking a More Equitable World for Both Humans and Non-Humans

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ECNU Review of Education 2024年第2期7卷 241-251页

作者：林静 Shue-kei Joanna Mok virginia Gomes Department of Counseling Higher Education and Special EducationCollege of Education3214 Benjamin BuildingUniversity of MarylandCollege ParkMD20742USA

Highlights In this article,we contend that the bedrock of an equitable world lies in the profound recognition of love as the fundamental force permeating the *** believe that love is built into the essence of who we *** posit that genuine progress toward an equitable world is elusive unless we place love,both for one another and for the natural world,at the core of our educational endeavors.

关键词： Embodied practices heart and spirit love and equity love as a cosmic force

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Ca-based materials derived from calcined cigarette butts for CO_(2)capture and thermochemical energy storage

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Journal of Environmental Sciences 2024年第6期140卷 230-241页

作者： Nabil Amghar virginia Moreno Pedro E.Sánchez-Jiménez Antonio Perejón Luis A.Pérez-Maqueda Instituto de Ciencia de Materiales de Sevilla C.S.I.C.-Universidad de SevillaC.Américo Vespucio4941092 SevillaSpain Instituto de Tecnología de Materiales(ITM) Universitat Politècnica de València(UPV)Plaza Ferrándiz y Carbonell 1AlcoyAlicante 03801Spain Departamento de Química Inorgánica Facultad de QuímicaUniversidad de Sevilla41012 SevillaSpain

Cigarette butts(CBs)are one of the most common types of litter in the *** to the toxic substances they contain,the waste generated poses a harmful risk to the environment,and therefore there is an urgent need for alternative solutions to landfill ***,this work presents a possible revalorization of this waste material,which implies interesting environmental *** were used as sacrificial templates for the preparation of CaO-based materials by impregnation with calcium and magnesium nitrates followed by flaming *** materials presented enhanced porosity for their use in the Calcium Looping process applied either to thermochemical energy storage or CO_(2)capture *** influence of the concentration of Ca and Mg in the impregnating solutions on the multicycle reactivity of the samples was *** improved multicycle performance was obtained in terms of conversion for both applications.

关键词： Cigarette butts Calcium-Looping CO_(2)Capture Thermochemical energy storage

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Characterization of Arroyo Verde Epithermal Deposit:Paragenesis,Mineral Geochemistry,Geochronology and Fluid Inclusions in Lower Chon Aike Volcanism,Argentina

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Journal of Earth Science 2024年第1期35卷 62-84页

作者： Cecilia Pavón Pivetta Leonardo Benedini Paulo Marcos Ma.Agustina Cócola Mercedes virginia Barros Daniel Gregori Leonardo Strazzere Anderson Costa dos Santos Mauro C.Geraldes Instituto Geologico del Sur(INGEOSUR) Universidad Nacional del Sur(UNS)-Consejo Nacional de Investigaciones Cientificas y Tecnicas(CONICET)Bahia Blanca 8000Argentina Dpto.de Geologia Universidad Nacional del Sur(UNS)Bahia Blanca 8000Argentina Universidad Nacional de Rio Negro Instituto de Investigacion en Paleobiologia y GeologiaGeneral Roca 8332Argentina Universidade do Estado do Rio de Janeiro Faculdade de GeologiaDepartamento de Mineralogia e Petrologia igneaRiodeJaneiro20559-900Brazil Geobiotec Departamento de GeocienciasUniversidade de AveiroAveiro 3800-002Portuga

Arroyo Verde epithermal deposit,in the North Patagonia region of Argentina,is located within the Lower Chon Aike volcanism and is developed between 192.6±2.5 Ma(mineralization host rock)and 189.5±2.6 Ma(overlying lava).Marifil volcanic complex is the host rock for these veins,veinlets and *** particular small deposit has developed low to intermediate sulphidation characteristics,with gangue mineral textures associated with several ore *** probe microanalysis determines electrum,silver minerals such as acanthite,and tetrahedrite,related Ag-Cu minerals like jalpaite,mckinstryite,stromeyerite,and base metals like chalcopyrite,sphalerite,galena and *** inclusions in quartz of two out of five events indicate that these Low Jurassic veins were formed due to subtle boiling and dilution mechanisms and by low-salinity(3.4 wt.%to 6.7 wt.%NaCl Eq)magmatic-hydrothermal fluid at 225 to 310℃.The fluid inclusion measurements that indicate boiling(Event 3)were plotted,and based on this data,we interpret that the Arroyo Verde deposit has been eroded between 550 and 700 *** particular character has not been previously recorded for other sectors of the eastern north Patagonian region.

关键词： epithermal deposit Ag minerals mineral geochemistry fluid inclusions Chon Aike geochronology

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Mathematical Modeling of HIV Investigating the Effect of Inconsistent Treatment

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1063-1078页

作者： Sr Mary Nyambura Mwangi virginia M. Kitetu Isaac O. Okwany Department of Mathematics and Actuarial Science Catholic University of Eastern Africa Nairobi Kenya

HIV is a retrovirus that infects and impairs the cells and functions of the immune system. It has caused a great challenge to global public health systems and leads to Acquired Immunodeficiency Syndrome (AIDS), if not attended to in good time. Antiretroviral therapy is used for managing the virus in a patient’s lifetime. Some of the symptoms of the disease include lean body mass and many opportunistic infections. This study has developed a SIAT mathematical model to investigate the impact of inconsistency in treatment of the disease. The arising non-linear differential equations have been obtained and analyzed. The DFE and its stability have been obtained and the study found that it is locally asymptotically stable when the basic reproduction number is less than unity. The endemic equilibrium has been obtained and found to be globally asymptotically stable when the basic reproduction number is greater than unity. Numerical solutions have been obtained and analyzed to give the trends in the spread dynamics. The inconsistency in treatment uptake has been analyzed through the numerical solutions. The study found that when the treatment rate of those infected increases, it leads to an increase in treatment population, which slows down the spread of HIV and vice versa. An increase in the rate of treatment of those with AIDS leads to a decrease in the AIDS population, the reverse happens when this rate decreases. The study recommends that the community involvement in advocating for consistent treatment of HIV to curb the spread of the disease.

关键词： HIV Modeling Mathematical Modeling Reproduction Number Inconsistent Treatment

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Mathematical Modeling of the Co-Infection Dynamics of HIV and Tuberculosis Incorporating Inconsistency in HIV Treatment

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Journal of Applied Mathematics and Physics 2024年第5期12卷 1744-1768页

作者： Sr Mary Nyambura Mwangi virginia M. Kitetu Isaac O. Okwany Department of Mathematics and Actuarial Science Catholic University of Eastern Africa Nairobi Kenya

A non-linear HIV-TB co-infection has been formulated and analyzed. The positivity and invariant region has been established. The disease free equilibrium and its stability has been determined. The local stability was determined and found to be stable under given conditions. The basic reproduction number was obtained and according to findings, co-infection diminishes when this number is less than unity, and persists when the number is greater than unity. The global stability of the endemic equilibrium was calculated. The impact of HIV on TB was established as well as the impact of TB on HIV. Numerical solution was also done and the findings indicate that when the rate of HIV treatment increases the latent TB increases while the co-infected population decreases. When the rate of HIV treatment decreases the latent TB population decreases and the co-infected population increases. Encouraging communities to prioritize the consistent treatment of HIV infected individuals must be emphasized in order to reduce the scourge of HIV-TB co-infection.

关键词： Co-Infection Modeling HIV-TB Co-Infection Mathematical Modeling Reproduction Number Inconsistent Treatment

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Evaluation of Human Impacts on Bartlett Pond Ecosystem, Laredo, Southern Texas, USA, through Empirical Modeling

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Journal of Environmental Protection 2024年第4期15卷 497-526页

作者： Maya P. Bhatt Amede Rubio Ganesh B. Malla Cristobal Lopez virginia Morales Erick Vazquez Cano David Marquez Orlando Berumen Alvarez Alfred Addo-Mensah Department of Biology and Chemistry Texas A&M International University Laredo USA Department of Mathematics Computer Geology and Physics University of Cincinnati-Clermont College Batavia USA

The trace elements chemistry of Bartlett Pond, a small shallow wetland pond in Laredo, Southern Texas, was sampled to evaluate the dynamics of trace elements impacts on water quality and ecosystems ecology of the pond. Two types of fish (bass and tilapia) were also sampled to see the trace element accumulation in different parts of their body. The concentrations of trace elements in water samples were found in the following order: Fe ≫Sb > Pb > As ≫Co > Tl > Cr > Cd within Bartlett Pond. Overall, the water quality of the pond is unacceptable for drinking and any other purposes as trace element concentrations (e.g. As, Cd, Co, Cr, Pb, Fe, Sb and Tl) are exceedingly higher (several fold) than the WHO and US EPA guidelines. Predictive and correlation analysis shows that most trace elements exhibit a strong positive correlation among them indicating the same anthropogenic sources and biogeochemical processes regulate these trace elements within the pond. Distributions of the trace elements in water exhibit different shapes mostly as positively skewed distribution for As, Cd, Co, Cr, and Tl, symmetrical distribution for Fe and almost symmetrical distribution for Pb and Sb. Concentrations of As, Co and Tl accumulated much higher in different parts of the Bass than Tilapia fish. The concentrations of As, Tl, Co, and Sb appeared significantly higher in different parts of the body of both Bass and Tilapia than the maximum SRM certified values. Accumulation of these contaminants in fish tissues pose increased health risks to humans who consume these contaminated fish although fishing is prohibited. Anthropogenic activities in the region primarily degrade the whole pond ecosystem ecology of the Bartlett Pond and waters of this pond to be not recommended for any use. These findings may be useful for the scientific community and concerned authorities to improve understanding about these precious natural resources and conservation of the ecosystem ecology.

关键词： Trace Elements Bartlett Pond Laredo Southern Texas Wetlands Ecosystem Ecology

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Minimizing sperm oxidative stress using nanotechnology for breeding programs in rams

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Journal of Animal Science and Biotechnology 2023年第6期14卷 2395-2410页

作者： Alejandro Jurado‑campos Pedro Javier Soria‑Meneses Maria Arenas‑Moreira Carlos Alonso‑Moreno virginia Rodriguez‑Robledo Ana Josefa Soler Jose Julian Garde Maria del Rocio Fernandez‑Santos SaBio IREC(CSIC-UCLM-JCCM) Campus UniversitarioS/N02071 AlbaceteSpain. Departamento de Quimica Inorganica Organica Y Bioquimica‑Centro de Innovacion en Quimica Avanzada(ORFEO‑CINQA)Facultad de FarmaciaUniversidad de Castilla-La Mancha02008 AlbaceteSpain. Centro Regional de Investigacion Biomedicas Unidad nanoDrugUniversidad de Castilla-La Mancha02008 AlbaceteSpain. Facultad de Farmacia Universidad de Castilla La Mancha02071 AlbaceteSpain.

Background Artificial insemination(AI)is a routine breeding technology in animal ***,the temperature-sensitive nature and short fertile lifespan of ram sperm samples hamper its use in *** this sense,nanotechnology is an interesting tool to improve sperm protection due to the development of nanomaterials for AI,which could be used as delivery *** this work,we explored the feasibility of vitamin E nanoemulsion(NE)for improving sperm quality during *** With the aim of evaluating this proposal,ejaculates of 7 mature rams of Manchega breed were collected by artificial vagina and extended to 60×10^(6)spz/mL in *** containing control and NE(12 mmol/L)with and without exogenous oxidative stress(100μmol/L Fe2+/ascorbate)were stored at 22 and 15℃and motility(CASA),viability(YO-PRO/PI),acrosomal integrity(PNA-FITC/PI),mitochondrial membrane potential(Mitotracker Deep Red 633),lipoperoxidation(C11 BODIPY 581/591),intracellular reactive oxygen species(ROS)production and DNA status(SCSAR)monitored during 96 *** results show that NE could be used to maintain ram spermatozoa during transport at 15 and 22℃for up to 96 h,with no appreciable loss of kinematic and physiological characteristics of freshly collected *** The storage of ram spermatozoa in liquid form for 2-5 d with vitamin E nanoemulsions may lead more flexibility to breeders in AI *** view of the potential and high versatility of these nanodevices,further studies are being carried out to assess the proposed sperm preservation medium on fertility after artificial insemination.

关键词： Breeding technology Nanoemulsions Nanotechnology Sperm oxidative stress Vitamin E

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