853 resultados para Contaminació atmosfèrica
Resumo:
Several methods and approaches for measuring parameters to determine fecal sources of pollution in water have been developed in recent years. No single microbial or chemical parameter has proved sufficient to determine the source of fecal pollution. Combinations of parameters involving at least one discriminating indicator and one universal fecal indicator offer the most promising solutions for qualitative and quantitative analyses. The universal (nondiscriminating) fecal indicator provides quantitative information regarding the fecal load. The discriminating indicator contributes to the identification of a specific source. The relative values of the parameters derived from both kinds of indicators could provide information regarding the contribution to the total fecal load from each origin. It is also essential that both parameters characteristically persist in the environment for similar periods. Numerical analysis, such as inductive learning methods, could be used to select the most suitable and the lowest number of parameters to develop predictive models. These combinations of parameters provide information on factors affecting the models, such as dilution, specific types of animal source, persistence of microbial tracers, and complex mixtures from different sources. The combined use of the enumeration of somatic coliphages and the enumeration of Bacteroides-phages using different host specific strains (one from humans and another from pigs), both selected using the suggested approach, provides a feasible model for quantitative and qualitative analyses of fecal source identification.
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A plot study was conducted to assess changes in Cd phytoavailability to a tomato cultivar in an agricultural soil in Southeastern Spain amended in two different ways (A and B), under controlled conditions. The experimental soil corresponded to a fine-loamy carbonatic thermic Calcidic Haploxeroll (Soil Survey Staff, 1998). A) Soil was amended with a single application of sewage sludge from a municipal source that had a total Cd concentration of 0.5 mg kg-1 at a rate that represented a final average concentration in the mixture of soil and sludge of less than 50 µg Cd kg-1. B) The amendment consisted of the addition of a mineral fertiliser with the same amount of NPK as in the sewage sludge application. The final levels of Cd were supposed to be negligible. A plot series without amendments was also performed (C). DTPA plus triethanolamine, and ammonium acetate extractable fractions in soils were analysed for all the plots. The time-dependent Cd accumulation in different parts of the tomato plants was studied by means of a Cd salt treatment. For each block (A, B, and C) four levels of Cd (0, 3, 30, 100 mg kg-1) were added as CdCl2. There was a significant increase in plant Cd after the initial cropping. Tomato stems, leaves and fruits were analysed separately for Cd determination. Differential Cd distribution and accumulation in tomato parts was detected.
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In the present study, we examined seawater biofiltration in terms of adenosine triphosphate (ATP) and turbidity. A pilot biofilter continuously fed with fresh seawater reduced both turbidity and biological activity measured by ATP. Experiments operated with an empty bed contact time (EBCT) of between 2 and 14 min resulted in cellular ATP removals of 32% to 60% and turbidity removals of 38% to 75%. Analysis of the water from backwashing the biofilter revealed that the first half of the biofilter concentrated around 80% of the active biomass and colloidal material that produces turbidity. By reducing the EBCT, the biological activity moved from the first part of the biofilter to the end. Balances of cellular ATP and turbidity between consecutive backwashings indicated that the biological activity generated in the biofilter represented more than 90% of the detached cellular ATP. In contrast, the trapped ATP was less than 10% of the overall cellular ATP detached during the backwashing process. Furthermore, the biological activity generated in the biofilter seemed to be more dependent on the elapsed time than the volume filtered. In contrast, the turbidity trapped in the biofilter was proportional to the volume filtered, although a slightly higher amount of turbidity was found in the backwashing water; this was probably due to attrition of the bed medium. Finally, no correlations were found between turbidity and ATP, indicating that the two parameters focus on different matter. This suggests that turbidity should not be used as an alternative to cellular concentration.
Resumo:
Recently, three new polyomaviruses (KI, WU and Merkel cell polyomavirus) have been reported to infect humans. It has also been suggested that lymphotropic polyomavirus, a virus of simian origin, infects humans. KI and WU polyomaviruses have been detected mainly in specimens from the respiratory tract while Merkel cell polyomavirus has been described in a very high percentage of Merkel cell carcinomas. The distribution, excretion level and transmission routes of these viruses remain unknown. Here we analyzed the presence and characteristics of newly described human polyomaviruses in urban sewage and river water in order to assess the excretion level and the potential role of water as a route of transmission of these viruses. Nested-PCR assays were designed for the sensitive detection of the viruses studied and the amplicons obtained were confirmed by sequencing analysis. The viruses were concentrated following a methodology previously developed for the detection of JC and BK human polyomaviruses in environmental samples. JC polyomavirus and human adenoviruses were used as markers of human contamination in the samples. Merkel cell polyomavirus was detected in 7/8 urban sewage samples collected and in 2/7 river water samples. Also one urine sample from a pregnant woman, out of 4 samples analyzed, was positive for this virus. KI and WU polyomaviruses were identified in 1/8 and 2/8 sewage samples respectively. The viral strains detected were highly homologous with other strains reported from several other geographical areas. Lymphotropic polyomavirus was not detected in any of the 13 sewage neither in 9 biosolid/sludge samples analyzed. This is the first description of a virus isolated from sewage and river water with a strong association with cancer. Our data indicate that the Merkel cell polyomavirus is prevalent in the population and that it may be disseminated through the fecal/urine contamination of water. The procedure developed may constitute a useful tool for studying the excreted strains, prevalence and transmission of these recently described polyomaviruses.
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We present a detailed evaluation of the seasonal performance of the Community Multiscale Air Quality (CMAQ) modelling system and the PSU/NCAR meteorological model coupled to a new Numerical Emission Model for Air Quality (MNEQA). The combined system simulates air quality at a fine resolution (3 km as horizontal resolution and 1 h as temporal resolution) in north-eastern Spain, where problems of ozone pollution are frequent. An extensive database compiled over two periods, from May to September 2009 and 2010, is used to evaluate meteorological simulations and chemical outputs. Our results indicate that the model accurately reproduces hourly and 1-h and 8-h maximum ozone surface concentrations measured at the air quality stations, as statistical values fall within the EPA and EU recommendations. However, to further improve forecast accuracy, three simple bias-adjustment techniques mean subtraction (MS), ratio adjustment (RA), and hybrid forecast (HF) based on 10 days of available comparisons are applied. The results show that the MS technique performed better than RA or HF, although all the bias-adjustment techniques significantly reduce the systematic errors in ozone forecasts.
Resumo:
Se ha estudiado la lixiviación de concentrados de cobre con alto contenido de arsénico (hasta 2,5 %), mediante un proceso de oxidación con cloro formado 'in situ', por la reacción entre hipoclorito de sodio y ácido sulfúrico. El objetivo de estas experiencias es producir una solución de lixiviación, de características adecuadas para entrar a la etapa posterior de extracción por solventes (SX), es decir, entre 4 a 6 g/1 de cobre y 5 a 7 g/1 de ácido residual. Esta disolución, además, deberá contener cantidades mínimas de arsénico y cloruro. Las lixiviaciones se realizaron por agitación en un reactor de acrílico diseñado para tal efecto, a temperatura ambiente y a presión atmosférica. Se utilizaron concentrados de cobre de explotaciones mineras de Antofagasta (Chile). Se estudiaron algunas variables típicas de la lixiviación, como son: la concentración de agente lixiviante, el tiempo de lixiviación, el porcentaje de sólidos y la temperatura. La caracterización de algunos residuos sólidos, producto de las lixiviaciones, se realizó por DRX (Difracción de Rayos X) y EDS (Barrido de Energía Dispersiva de Rayos X). El cobre y arsénico en las disoluciones se analizaron mediante Espectroscopia de Absorción Atómica. Los resultados experimentales indican que es posible obtener soluciones de las características deseadas con este procedimiento, que utiliza reactivos comunes y de relativo bajo costo.
Resumo:
The determination of gross alpha, gross beta and 226Ra activity in natural waters is useful in a wide range of environmental studies. Furthermore, gross alpha and gross beta parameters are included in international legislation on the quality of drinking water [Council Directive 98/83/EC].1 In this work, a low-background liquid scintillation counter (Wallac, Quantulus 1220) was used to simultaneously determine gross alpha, gross beta and 226Ra activity in natural water samples. Sample preparation involved evaporation to remove 222Rn and its short-lived decay daughters. The evaporation process concentrated the sample ten-fold. Afterwards, a sample aliquot of 8 mL was mixed with 12 mL of Ultima Gold AB scintillation cocktail in low-diffusion vials. In this study, a theoretical mathematical model based on secular equilibrium conditions between 226Ra and its short-lived decay daughters is presented. The proposed model makes it possible to determine 226Ra activity from two measurements. These measurements also allow determining gross alpha and gross beta simultaneously. To validate the proposed model, spiked samples with different activity levels for each parameter were analysed. Additionally, to evaluate the model's applicability in natural water, eight natural water samples from different parts of Spain were analysed. The eight natural water samples were also characterised by alpha spectrometry for the naturally occurring isotopes of uranium (234U, 235U and 238U), radium (224Ra and 226Ra), 210Po and 232Th. The results for gross alpha and 226Ra activity were compared with alpha spectrometry characterization, and an acceptable concordance was obtained.
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Despite the low biodegradability of seawater NOM, problems associated with biofouling are common in facilities that handle seawater. In this work, a fixed-film aerobic biofilter is proposed as an effective unit for preventing biofouling in such facilities. A packed-bed biofilter with an EBCT = 6 - 11 min was employed. The results demonstrated that the DOC is reduced by 6% and the BOD7 is reduced up to 15%. The LC-OCD analysis revealed that biofiltration abates the LMW neutrals and biopolymer fractions by 33 and 17%, respectively. However, the fractionation with UF membrane showed that the biofiltration process is able to degrade the more biodegradable compounds that have molecular weights that are greater than 1 kDa and compounds with molecular weights of less than 1 kDa. After biofiltration, the biological activity measured in terms of ATP removal was reduced by 60%. Finally, a test to evaluate the biofilm formation capacity of a water sample revealed reductions of ~94% when comparing biofiltered and non-biofiltered seawater. Therefore, a fixed-film aerobic biofiltration process could be a useful treatment for the removal of biodegradable organic matter from seawater and for improving the water quality in terms of less biofilm formation capacity.
Resumo:
The influence of storage time and temperature on Sb migration from PET bottles into mineral water was studied in short-term tests lasting up to 15 days and long-term studies lasting up to 220 days. Samples purchased were stored in three different coloured bottles: clear (CL), light blue (LB) and dark blue (DB). Sb migration was assayed by HG-AFS for total determination and HPLC-ICP-MS for speciation analysis. Migration studies showed that waters stored at 4 and 20 oC were not subject to Sb migration. At 40 oC there was a significant increase in Sb concentration, although the maximum limit established by the European Union (5.0 ug/L) was not exceeded, whereas at 60 oC samples were subject to considerable Sb migration after 30 days of storage. In this case, the maximum limit established by the European Union was exceeded and both Sb (V) and Sb (III) were detected.
Resumo:
This article describes a photocatalytic nanostructured anatase coating deposited by cold gas spray (CGS)supported on titanium sub-oxide (TiO22x) coatings obtained by atmospheric plasma spray (APS) onto stainless steel cylinders. The photocatalytic coating was homogeneous and preserved the composition and nanostructure of the starting powder. The inner titanium sub-oxide coating favored the deposition of anatase particles in the solid state. Agglomerated nano-TiO2 particles fragmented when impacting onto the hard surface of the APS TiO22x bond coat. The rough surface provided by APS provided an ideal scenario for entrapping the nanostructured particles, which may be adhered onto the bond coat due to chemical bonding; a possible bonding mechanism is described. Photocatalytic experiments showed that CGS nano-TiO2 coating was active for photodegrading phenol and formic acid under aqueous conditions. The results were similar to the performance obtained by competitor technologies and materials such as dip-coating P25 photocatalysts. Disparity in the final performance of the photoactive materials may have been caused by differences in grain size and the crystalline composition of titanium dioxide.
Resumo:
El dol és un conjunt de processos psicològics i psicosocials que són resultat de la pèrdua d’un ésser al qual la persona estava vinculada afectivament. Aquest treball presenta un programa d’educació per a la salut per ajudar a superar el procés del dol en l’atenció primària. L’objectiu del programa és proporcionar, a les persones que han patit una pèrdua, els instruments necessaris per a elaborar un bon procés de dol. Proposo un programa d’educació sanitària grupal de 8 sessions. Hi ha marcats uns objectius educatius i de salut, juntament amb uns criteris de resultat. L’avaluació es realitza a través d’un qüestionari i una entrevista individual i una altra grupal, per valorar si s’han aconseguit els objectius proposats. Paraules clau: dol, acompanyament a persones en dol, programa sanitari, atenció primària, suport emocional, teràpia, tècniques de comunicació, grups de suport al dol
Resumo:
El papel de la enfermería se ha visto sometido a muchos cambios desde sus inicios hasta la actualidad. Cambios que han ayudado a que la profesión crezca y a que se fundamente en un cuerpo de conocimientos propios. Las enfermeras, inicialmente supeditadas al estamento médico, se encuentran actualmente con un nivel de formación que les permite desarrollar su rol autónomo. Las nuevas necesidades de cuidados, generadas por los cambios socio-demográficos, epidemiológicos y políticos, y la necesidad de dar respuesta a la demanda de la población, han generado una nueva perspectiva de los sistemas de salud. Los sistemas sanitarios tratan de adaptarse a las nuevas circunstancias generando modelos sanitarios eficaces y económicamente sostenibles, donde la enfermera tiene un papel primordial. Para poder dar la atención necesaria y profesional a todo este nuevo modelo asistencial se está procediendo cada vez más y de manera más activa, a la implantación de nuevos roles enfermeros (enfermera/o gestora/or de casos, enfermera de Enlace, etc.). Dentro de estos roles, destaca el de enfermera/o en Cuidados Paliativos (CP) por su gran complejidad e incluso desconocimiento, debido a que es un rol relativamente reciente. Dada la importancia para el colectivo enfermero de conocer y comprender los cambios que ha experimentado la enfermería, el presente trabajo pretende obtener una visión general de la evolución histórica de la enfermería y la aparición de nuevos roles, profundizando en el rol de CP. Para ello se realiza una revisión de la literatura. Palabras clave: Roles enfermería, cuidado, historia enfermería, evolución enfermería, cuidados paliativos, enfermería paliativa.
Resumo:
La parada cardiorrespiratoria (PCR) dentro del hospital es considerada una emergencia vital y está demostrado que existe una relación directa entre la respuesta asistencial y la mortalidad asociada a este evento. Los resultados del tratamiento de la PCR son un indicador de calidad de los centros sanitarios. En el caso en concreto de España, la mayoría de hospitales no disponen de un sistema organizado e integral de atención a la PCR. A pesar de los avances en medicina y tecnológicos, la tasa de supervivencia no ha variado significativamente en los últimos 30 años por lo que se ha de considerar como un problema social, económico y sanitario de gran magnitud que cabe abordar con todas las herramientas disponibles. Objetivos: Conocer cómo se organiza la reanimación cardiopulmonar (RCP) dentro del hospital y conocer los planes integrales de RCP publicados por los hospitales españoles. Metodología: Se realiza una revisión de la literatura a través de las bibliotecas indexadas Pubmed y Web of Science mediante criterios de inclusión/exclusión, uso de operadores booleanos y búsqueda bibliográfica manual. Además se realiza una entrevista a un médico referente nacional en la investigación sobre RCP. Resultados: Se han encontrado 7 planes integrales para la atención a la PCR y solo 2 de ellos están avalados por el Plan Nacional de RCP (PNRCP), miembro del Consejo Español de RCP (CERCP). Conclusiones: Existe una falta de publicaciones por parte de los hospitales españoles sobre planes integrales para la organización de la RCP que cumplan los criterios de calidad necesarios. Si bien todos los hospitales disponen de protocolos propios dirigidos a sus profesionales para la actuación en caso de PCR, estos son de uso interno y solo tienen en común entre ellos el hecho de seguir las recomendaciones de las guías del European Resuscitation Council (ERC). III Es necesario que los centros sanitarios fomenten y compartan su actividad investigadora sobre el tema. Palabras clave: parada cardíaca hospitalaria, resucitación cardiopulmonar, Plan hospitalario de resucitación.
Resumo:
El joc es converteix en un problema de salut quan la persona perd el control de la seva conducta, anteposant-ho a les seves obligacions socials i familiars. Diversos estudis sobre el joc demostren que és una conducta iniciada en l'adolescència. La prevenció en salut es mostra fonamental en aquesta etapa del desenvolupament del jove, moment en el qual s'estableixen patrons de conducta. El propòsit d'aquest treball és realitzar un programa de prevenció orientat a evitar el joc patològic en adolescents. Els seus objectius són: Prevenir conductes que deriven en joc patològic per a adolescents; reduir o limitar les hores de joc, fomentant conductes i activitats alternatives; i fomentar la integració i participació del jove al programa com a mitjà d'assimilació dels conceptes exposats i mantenir la seva atenció en el curs del programa. Aquest programa es basa en el model Precedeix i en la teoria Cognitiu-Social de Bandura. Està dirigit a joves de tots dos sexes, escolaritzats a Terrassa, d'entre 15 i 17 anys. Les variables d'interès són edat, sexe; edat, professió i situació social dels seus pares; entorn social, accés a internet. No es considerarà si el jove ha tingut problemes similars precedents. Constarà de sis sessions de 1h. en les quals s'explicaran les conseqüències del joc patològic i la forma d'adquisició d'aquesta conducta, la relació conductual del jove entorn del joc, els factors de risc i protecció que envolten al joc, i es fomentarà l'autoconcienciación del jove referent a la seva conducta, tenint també en compte el seu entorn social. Es realitzarà una sessió final evaluativa d'anàlisi de funcionament i avaluació del programa tant per part del jove com del ponent. Els resultats esperats de la implementació del programa són: Un millor control i coneixement del joc, reducció del temps de joc i el reconeixement de patrons de conducta inadequats per part del jove.
Resumo:
Junto a los medios puramente administrativos orientados a la protección del medio ambiente, cada día adquieren mayor protagonismo los que pueden adoptarse desde el ámbito del derecho financiero, del ingreso y gasto públicos. El trabajo se ha estructurado en cuatro apartados: aguas, residuos sólidos, polución atmosférica y contaminación acústica.