999 resultados para Aigua potable -- Toxicologia


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There is an increasing interest in micropollutants in the environment that can interfere with the endocrine system, affecting health, growth and reproduction of animals and humans. These substances are known as Endocrine Disrupting Chemicals (EDCs) and can be found in domestic sewage, domestic wastewater treatment plant effluents, and in natural and potable waters. There are numerous chemicals classified as EDCs, such as pesticides, chemicals used and produced by chemical industries and natural and synthetic estrogens. EDCs can be related to the increase of the incidence of anomalies in the reproductive system of animals, cancer in humans and reduction of the masculine fertility.

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Irrigation has traditionally constituted one of the most characteristic and emblematic agricultural mosaics of the Mediterranean as a key factor of socio-economic dynamism of the territorial matrix. In recent years there has been an important scientific, intellectual and social environment mobilization around water uses and, in particular, around the main socio-economic use of resource: irrigation, which is undergoing an intense and accelerated transformation process. Thus, in parallel with the decline of traditional irrigation systems, located in areas with natural availability of water, fertile soil and appropriate topographic conditions, the socio-economic changes in the last decade have stimulated the appearance of new irrigated areas with environmental, social and economic disparate characteristics. As a result, the irrigation management model has been conditioned to respond to the new parameters of water scarcity and resource efficiency. In addition, policies and actors have evolved over time as a consequence of disparate priorities –and often conflicting– in terms of irrigation, making necessary the gear of different discourses. In this context, the Model of social commitment of irrigation proposed by the Institutional and Social Innovations in Irrigation Mediterranean Management (ISIIMM) can become a starting example

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Partint del projecte bàsic d’un habitatge unifamiliar aïllat, projectat amb sistema prefabricat, onhi ha definida l’arquitectura i de forma molt bàsica el sistema estructural, els tancaments, lesinstal•lacions i els acabats, es pretén realitzar un estudi que es basi en la millora de l’envoltantespaial i de les instal•lacions per tal d’aconseguir un habitatge energèticament més eficientrespecte a la proposada inicialment.Concretament, es tracta d’un habitatge unifamiliar aïllat, del model tipus “CUBIC EVOLUTION”,dissenyat pels arquitectes Joaquin Torres i Rafael Llamazares de l’estudi d’arquitectura A-Cero.Aquest model, presenta una superfície de 290,91m2 útils i de 342,76m2 construïts, distribuïtsd’una manera molt raonable al seu ús.Per tant, l’objectiu principal d’aquest projecte final de grau, és projectar el condicionament del’envoltant, de totes les instal•lacions amb sistemes renovables i sostenibles necessàries en lavivenda i de diferents sistemes passius d’estalvi energètic de la vivenda prefabricada de l’estildescrit anteriorment, tenint presents criteris de sostenibilitat i autosuficiència, sense deixar debanda la condició estètica de la vivenda proposada en el projecte bàsic, de manera que aquestaes pugui autosubministrar la major part de l’energia i aigua que necessita, i complint sempre lanormativa actual.També es tindran en compte aspectes bioclimàtics, tals com ubicació, orientació, il•luminaciónatural, ventilació natural, pluja, etc., per tal d’adaptar-se a les condicions climàtiques i de l’entornon està situada i permetre a l’edifici estalviar la major quantitat d’energia possible

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Els processos de mecanitzat amb arrencament de ferritja consisteixen en arrencar contínuament petits fragments de material de la peça a la que es vol donar forma mitjançant les eines de tall. En treballar amb metalls, aquestes forces de tall són importants, i provoquen el desgast de les eines així com un escalfament important de l’eina i la peça. Per aquest motiu s’introdueixen els olis de tall, amb les principals funcions de refrigerar i lubricar. Tradicionalment, aquests olis de tall s’han subministrat a raig, quedant la zona de treball inundada. Els últims anys, degut a les millores tecnològiques i per intentar estalviar amb olis de tall, s’ha ideat un nou sistema anomenat mínima quantitat de lubricant, el qual subministra petites gotes d’oli, no soluble en aigua, dins un flux d’aire a pressió. Aquest sistema, a més, s’injecta prop de la zona de treball, on és estricament necessari. Aquest sistema redueix considerablement el consum d’oli de tall, i a més, augmenta l’eficiència de lalubricació. A part, elimina els posteriors tractaments per reciclar l’oli de tall un cop perd les seves propietats. Per aquest motiu, es pretén estudiar la utilització d’un mètode semblant al de la mínima quantitat de lubricant, subministrant el mateix oli de tall que s’utilitza convencionalment però polvoritzar per tal de convertir-lo en un aerosol

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Estudi de la climatització d'una instal•lació esportiva,concretament una piscina coberta municipal, a partir de la calor recuperada de les aigües residuals urbanes (ARU) que produeix una població de 30.000 habitants. En la primera part de l'estudi s'ha calculat la potència màxima per cobrir les quatrenecessitats de la instal•lació en règim estacionari, que ha resultat ser de 265,8 kW,repartits en 69,1 kW per cobrir les necessitats del vas de la piscina, 102,5 kW percobrir les necessitats en l'aire interior de la sala de la piscina, 30,2 kW per cobrir lesnecessitats tèrmiques calorífiques de les sales annexes i 64 kW per cobrir lesnecessitats en la producció d'aigua calenta sanitària (ACS). A continuació també s'hadeterminat l'estimació de la despesa total anual de la instal•lació que és de 1.179MWh/any. El 48% aproximadament de la despesa total es destina a cobrir lesnecessitats del vas de la piscina, el 28% per cobrir la producció d'ACS, el 20% percobrir les necessitats de la sala de la piscina i el 4% per cobrir les necessitatscalorífiques a hivern de les sales annexes

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The implementation of the subject Pharmacology and Toxicology in R+D+i in the Pharmacy Degree, has led to the launch of a new methodological approach and teaching performance with the aim of developing the generic skills of the University of Barcelona (e.g., self-learning, team-working). An additional objective was students' integration of knowledge from different subjects in the degree which form the basis of the preclinical and clinical development of a drug. For this purpose, the teaching strategy used in the development of the subject was based on: 1) re-developing the content that students had been taught previously or were being taught in the same semester as a part of other subjects, and framing them in the environment of the pharmaceutical industry, 2) introducing new and previously unseen contents to do with drug development and toxicology, 3) developing a battery of activities to be undertaken by teams of students relating to the R+D+i of a particular drug. During the development of these activities, students have to acquire generic skills in addition to the subject-specific skills. The results obtained from the student survey give us grounds for satisfaction and allow us to consider that we have reached the goal of improving students' learning in Pharmacology and Toxicology applied to drug development in the pharmaceutical world today.

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Objetivo: El propósito del estudio fue comparar los niveles de mercurio en cabello en dos muestras de ninos peruanos provenientes de dos zonas geográficas distintas: una zona rural minera y una zona urbana. Material y métodos: La zona minera correspondió al poblado de Mollehuaca (Arequipa), de donde se obtuvieron 52 muestras de cabello; la zona urbana no expuesta a minería correspondió al distrito de Los Olivos (Lima), de donde se obtuvieron 40 muestras. Se determinó el nivel de mercurio con la técnica estandarizada de plasma de inducción acoplado con un espectrómetro de masas (ICP-MS). Resultados: En la zona rural, en promedio, se obtuvo un nivel de mercurio de 7,47 ppb±26,9. En la zona urbana, el nivel de mercurio alcanzó un promedio de 2,47 ppb±1,28. No se encontraron diferencias significatives en el nivel de mercurio según edad o género. Conclusión: Se concluye que el grupo expuesto a minería aurífera informal y de zona rural presentó niveles de mercurio en cabello en promedio mayores a los del grupo de zona urbana, pero esta diferencia no fue significativa (p=0,188, α=0,05).

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La natura és sàvia i, després d'anys d'evolució, ha seleccionat materials amb propietats insuperables. Alguns experts creuen que el 80% de les solucions que la ciència busca estan en els animals i les plantes. S'investiga per aconseguir avions inspirats en el vol del cigne, edificis que imitin la termoregulació dels cactus, banyadors basats en les escates dels taurons per reduir la fricció amb l'aigua i materials tan resistents com les teranyines.

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Peer Reviewed

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Jundiaí river is the main stream in the Jundiaí Hydrographic Basin and its water is not considered safe for public supply. The water problem is getting worse with the development of the region. The Pirai stream, have been one of the last potable water resource. With the purpose of investigating the sediment quality, due to its influence on the water quality, bioavailable and total Cd and Pb were determined using TS-FF-AAS. Total Cd and Pb up to 2.47 and 24.7 µg g-1 were measured, respectively. The wastewater sludge showed concentrations of 4.01 and 171 µg g-1, for the same metals.

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The aim of this work was to analyze 17 β estradiol and estrone, natural estrogenic hormones present in domestic effluents and animal excreta, in the public water supply system of Jaboticabal, SP. The results have shown the presence of estrogens in 22% of the samples in concentrations from 6,8 ng L-1 (treated water) to 30,6 ng L-1 (riverhead) for 17 β estradiol and 600 ng L-1 of estrone (stream), respectively. We concluded that animal wastes, discharges from the wastewater treatment station, and discharges of domestic effluent without treatment from rural proprieties were probably the cause of this contamination.

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The restricted availability of water sources suitable for consumption and high costs for obtaining potable water has caused an increase of the conscience concerning the use. Thus, there is a high demand for "environmentally safe methods" which are according to the principles of Green Chemistry. Moreover, these methods should be able to provide reliable results for the analysis of water quality for various pollutants, such as phenol. In this work, greener alternatives for sample preparation for phenol determination in aqueous matrices are presented, which include: liquid phase microextraction, solid phase microextraction, flow analysis, cloud point extraction and aqueous two-phase systems.

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A method for simultaneous analysis of trihalomethanes and organochloride and pyrethroid pesticides in water utilizing SPME-HS and GC-ECD was developed. In the optimized method 25 mL of water containing 2% (w/v) Na2HPO4 were heated to 60 °C for 50 min. The fiber (PDMS - 100 μm) was exposed to a headspace for the same period. For all analytes it was found that LOQ < MCL (Maximum Contaminant Level), CV < 20% and r > 0.9. The method was applied to potable and surface water samples. Some trihalomethanes were encountered in potable waters, at levels below the MCL.

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Chemical coagulation is commonly used in raw water and wastewater treatment plants for the destabilisation of pollutants so that they can be removed in the subsequent separation processes. The most commonly used coagulation chemicals are aluminium and iron metal salts. Electrocoagulation technology has also been proposed for the treatment of raw waters and wastewaters. With this technology, metal cations are produced on the electrodes via electrolysis and these cations form various hydroxides in the water depending on the water pH. In addition to this main reaction, several side reactions, such as hydrogen bubble formation and the reduction of metals on cathodes, also take place in the cell. In this research, the applications of electrocoagulation were investigated in raw water treatment and wastewater applications. The surface water used in this research contained high concentrations of natural organic matter (NOM). The effect of the main parameters – current density, initial pH, electric charge per volume, temperature and electrolysis cell construction – on NOM removal were investigated. In the wastewater treatment studies, the removal of malodorous sulphides and toxic compounds from the wastewaters and debarking effluents were studied. Also, the main parameters of the treatment, such as initial pH and current density, were investigated. Aluminium electrodes were selected for the raw water treatment, whereas wastewaters and debarking effluent were treated with iron electrodes. According to results of this study, aluminium is more suitable electrode material for electrocoagulation applications because it produces Al(III) species. Metal ions and hydroxides produced by iron electrodes are less effective in the destabilisation of pollutants because iron electrodes produce more soluble and less charged Fe(II) species. However, Fe(II) can be effective in some special applications, such as sulphide removal. The resulting metal concentration is the main parameter affecting destabilisation of pollutants. Current density, treatment time, temperature and electrolysis cell construction affect the dissolution of electrodes and hence also the removal of pollutants. However, it seems that these parameters have minimal significance in the destabilization of the pollutants besides this effect (in the studied range of parameters). Initial pH and final pH have an effect on the dissolution of electrodes, but they also define what aluminium or iron species are formed in the solution and have an effect on the ζ-potential of all charged species in the solution. According to the results of this study, destabilisation mechanisms of pollutants by electrocoagulation and chemical coagulation are similar. Optimum DOC removal and low residual aluminium can be obtained simultaneously with electrocoagulation, which may be a significant benefit of electrocoagulation in surface water treatment compared to chemical coagulation. Surface water treatment with electrocoagulation can produce high quality water, which could be used as potable water or fresh water for industrial applications. In wastewater treatment applications, electrocoagulation can be used to precipitate malodorous sulphides to prevent their release into air. Technology seems to be able to remove some toxic pollutants from wastewater and could be used as pretreatment prior to treatment at a biological wastewater treatment plant. However, a thorough economic and ecological comparison of chemical coagulation and electrocoagulation is recommended, because these methods seem to be similar in pollutant destabilisation mechanisms, metal consumption and removal efficiency in most applications.

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Os aspectos epidemiológicos, clínicos e anatomopatológicos da intoxicação espontânea por aceturato de diminazeno foram estudados em 10 cães. Em todos os casos, os cães afetados demonstraram sinais de síndrome tálamo-cortical, principalmente alteração do nível de consciência, tetraparesia, rigidez extensora e crise convulsiva. Em alguns casos, os cães acometidos apresentaram sinais de síndrome cerebelar, como tremores musculares generalizados de alta frequência e baixa amplitude, e/ou de síndrome vestibular, como ataxia, inclinação de cabeça e quedas. Esses sinais ocorreram entre 24 e 48 horas após o uso do fármaco injetável por via intramuscular e se mantiveram até a morte ou eutanásia dos cães (entre 1 e 7 dias). Tais sinais clínicos refletiam encefalomalacia hemorrágica focal simétrica, que afetava a medula oblonga, a ponte, a medular do cerebelo, o tálamo, o mesencéfalo, os pedúnculos cerebelares e os núcleos da base. Esse artigo: 1) descreve e discute essa forma de intoxicação medicamentosa tão pouco citada na literatura internacional e desconhecida da maior parte dos clínicos e patologistas veterinários brasileiros, 2) estabelece critérios clínicos e anatomopatológicos para o seu diagnóstico e, principalmente, 3) atenta para os riscos da utilização desse princípio ativo na terapêutica canina.