The electrolyzed water is a type of water with biocidal properties, fungicidal and sporicidal. Its effectiveness is caused by its activation which gives it a high oxidation capacity. Therefore, electrolyzed water becomes a very effective breaker of cell membrane of microorganisms. Although during its activation, hypochlorous acid is released, it is instantly stabilised, which guarantees the safety in handling and respect for the environment. The aim of this study was to determine the effect of electrolyzed water as drinking water on the presence of bacteria in the water consumed by cows and the microbiological quality of milk produced. Water samples collected from drinking electrolyzed water showed negative results for contamination by aerobic, total coliforms, E. coli and faecal streptococci. Data showed a significant decrease of somatic cell count, total bacteriology and coagulase positive count in milk from cows that had drunk electrolyzed water.

The efficiency of a recirculation system for the cultivation of C. auratus, fed with natural and artificial diets was evaluated. The experiment consisted of four treatments with four replicates. The first two treatments used recirculation system and the last two static system. In the first and fourth treatment, animals were fed with brine shrimp biomass (50% CP), while in the second and third treatments a commercial flake ration (42% CP) was used. At the end of cultivation (60 days), water samples were taken from all experimental units and subjected to standard plate count for determining the density of mesophilic bacteria. Final weight (g), final length (cm), specific growth rate (% day -1) and weight gain (%) were significantly different (p | A eficiência de um sistema de recirculação para o cultivo de C. auratus, alimentados com dieta natural e artificial foi avaliada. O experimento consistiu de quatro tratamentos com quatro repetições. Os dois primeiros tratamentos utilizaram sistemas de recirculação e os dois últimos sistemas estáticos. No primeiro e quarto tratamento, os animais foram alimentados com biomassa de artêmia (PB 50%), enquanto nos tratamentos dois e três, com ração comercial em flocos (42% PB). Ao final do cultivo (60 dias), amostras de água foram coletadas em todas as unidades experimentais e submetidos a contagem padrão em placas para determinação da densidade de bactérias mesófilas. O peso final (g), com-primento final (cm), taxa de crescimento específico (% dia-1) e ganho de peso (%) foram signifi-cativamente diferentes (p

The urban environment has to be concerned with the integrated water resources management, which necessarily includes the concept of basin unity and governance.  The traditional urban water cycle framework, which includes water supply, sewerage and wastewater treatment services, is being replaced by a holistic and systemic concept, where water is associated with urbanism and sustainability policies. This global point of view cannot be ignored as new regulations demand systemic and environmental approaches to the administrations, for instance, in the management of urban drainage and sewerage systems. The practical expression of this whole cluster interactions is beginning to take shape in several countries, with the definition of Low Impact Development and Water Sensitivity Urban Design concepts. Intends to integrate this new strategic approach under the name: “Water Sensitive Urban Development” (WSUD). With WSUD approach, the current urban water systems (originally conceived under the traditional concept of urban water cycle) can be transformed, conceptual and physically, for an integrated management of the urban water system in new models of sustainable urban development. A WSUD implementing new approach to the management of pollution associated with stormwater in the urban water system is also presented, including advances in environmental regulations and incorporation of several techniques in Spain. | El medio urbano no es ajeno a la de gestión integrada del recurso hídrico, que incluye, necesariamente, el concepto de unidad de cuenca y de gobernanza. El tradicional concepto de ciclo del agua urbana, que incluye de un modo muy lineal los servicios de abastecimiento y saneamiento, debe ser sustituido por una visión más integral y sistémica, donde el agua se vincula con el planeamiento y el desarrollo urbano y con las políticas de sostenibilidad. Se puede hablar de sistema de agua urbana. Esta globalidad de acción no es algo de lo que podamos sustraernos, ya que la legislación cada vez más orienta a las administraciones a considerar aspectos sistémicos y ambientales a la hora de gestionar, por ejemplo, los sistemas de saneamiento y drenaje. La plasmación práctica de todo este conglomerado de interacciones ya toma forma en algunos países, en los que se comienza a hablar de “Low Impact Development” (LID) o “Water Sensitivity Urban Design” (WSUD). Se propone integrar este nuevo enfoque estratégico bajo la denominación: Desarrollo Urbano Sensible al Agua (DUSA). Con el impulso del enfoque DUSA, los actuales sistemas de agua urbana (concebidos originalmente bajo el concepto tradicional de ciclo de agua urbana) pueden transformarse, conceptual y físicamente, para una gestión integrada del sistema del agua urbana en los nuevos modelos de desarrollo urbanos sostenible.  Asimismo se presenta la aplicación del nuevo enfoque DUSA a la gestión de la contaminación asociada a las aguas pluviales en el sistema de agua urbana, incluyendo los avances en normativa e incorporación de técnicas en España.

O dimensionamento de motores com potência acima da necessária acarreta maior custo inicial, menor rendimento e menor fator de potência. Desde 1996, que se fabricam no Brasil motores elétricos com fator de serviço maior do que a unidade, obedecendo a valores prescritos em norma. O fator de serviço informa a potência disponível do motor em regime contínuo para as condições de carga nominal. A literatura técnica de dimensionamento de motores para acionamento de bombas hidráulicas indica a necessidade da adoção de acréscimos na potência dos motores. Tanto o fator de serviço, quanto o acréscimo na potência constituem fatores de segurança para o dimensionamento. Estes fatores de segurança têm a função de suprir maior demanda de potência devido a variações nas condições de trabalho, como curvas características da bomba ou do motor, e a qualidade de energia, como oscilação e desequilíbrio do sinal de tensão. Conclui-se que não seja utilizado acréscimo na potência no dimensionamento de motores com fator de serviço maior do que a unidade para acionamento de bomba hidráulica, tendo em vista que o superdimensionamento pode acarretar redução de rendimento do sistema e maior custo inicial. O dimensionamento que considera, simultaneamente, os dois fatores de segurança, implica superdimensionamento de 15% a 88%.<br>Sizing motors with power above the required implies in higher initial cost, lower performance and lower power factor. Since 1996, that electrical motor is built in Brazil with service factors greater than the unity, obeying the standard values. The service factor informs the motor's available power in continuous regime under nominal condition. The technical literature for sizing motors to operate hydraulic pumps indicates the need of adoption of sizing factors in the motor's power. Both the service factor and the sizing factor are security factors to size motors. These safety factors have the function to supply greater power demand due to changes in the working conditions such as, pump or motor characteristic curves, or energy quality like voltage imbalance or oscillation. The conclusion is that there is no need to use sizing factor for rating motors to drive hydraulic pump, because oversize may lead in performance decrease and greater initial costs. The size that considers both the security factors implies in an over sizing from 15% to 88%.

The current knowledge on the argentine continental shelf water masses is summarized in this paper. These water masses are characterized as a function of water types fed by the boundary currents and the modifications due to continental runoff, and water energy exchange with the atmosphere. Based on sea surface salinity distributions and the temperature-salinity characteristics, three masses are described: coastal waters, mid-shelf waters and slope waters. The main freshwater sources found along the coast are identified, as well as high salinity formation areas. The vertical stratification, mainly controlled by temperature, is analyzed along the annual cycle. The stratification cycle is mainly driven by the heat exchange between the atmosphere and the ocean. Finally the oceanic fronts in the Argentine Sea are cited. | Bibligraphic reference/Referencia bibliográfica: Guerrero, R.A.; Piola, A.R. 1997. Masas de agua en la plataforma continental. En: Boschi, E.E.; ed. Antecedentes históricos de las exploraciones en el mar y las características ambientales. Mar del Plata: Instituto Nacional de Investigación y Desarrollo Pesquero INIDEP. (El Mar Argentino y sus Recursos Pesqueros, 1) p.107-118 | Published | hidrografía, plataforma continental, circulación de agua, estratificación, frentes oceánicos, masas de agua

16 páginas, 3 cuadros, 12 figuras | [EN] The substitution of the ammonium chloride used as buffered solution in the determination of nitrate in sea water by cadmium-copper reduction to nitrite has been studied in this work in order to prevent the problem of contamination when ammonia is simultaneously determined with nitrate. A system of continous variation has been used in order to determine the optimum proportion of citric acid-sodium citrate solution to replace adequately the ammonium chloride as buffer of the reduction. The proportion found is 55 H:245 Na. Some variations have been introduced in the diazotation reagent and the effect of column length on reduction has also been studied | [ES] El objeto de este trabajo es sustituir el CINH, utilizado en la determinación de nitratos como tampón para la reducción a nitritos en columna de3 cadmio, con el fin de evitar los problemas de contaminación que este reactivo puede introducir en la determinación simultánea del ion amonio y del nitrato. Se utiliza un sistema de variación continua para obtener las condiciones óptimas de la reacción y se encuentra que una mezcla de cítrico:citrato (55 H:145 Na) puede ser usado como substituto del CINH, para tamponar el sistema de reducción. Asimismo se introducen algunas variaciones en el reactivo de diazotación y se estudia la influencia de la longitud de la columna de reducción | Peer reviewed

III Concurso de Fotografía. "Problemáticas ambientales en entornos urbanos" (Tercer Puesto). Se trata de un canal de agua que pasa por CENFER y por el terminal de trasporte de Bucaramanga, en el que se evidencia contaminación por químicos en el agua produciendo una gran cantidad de espuma que puede ser producida por altas cantidades de detergentes y surfactantes. | III Photography Contest. "Environmental problems in urban environments" (Third Place). This is a water channel that passes through CENFER and the Bucaramanga transportation terminal, in which chemical contamination is evident in the water, producing a large amount of foam that can be produced by high amounts of detergents and surfactants. | Modalidad Presencial