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1.
Environ Monit Assess ; 191(10): 624, 2019 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-31494720

RESUMEN

This study presents an approach on the evaluation of potential laminar erosion in the Ribeirão Sucuri Grande watershed. It is located in the northeast of the state of Goiás, Brazil, a conservation area under strong anthropogenic pressure. A Mamdani fuzzy inference system was designed using linguistic variables, pertinence functions, and a set of rules associated to a traditional laminar erosion prediction model through the environmental conditioners slope, erodibility, and degree of soil protection. The laminar erosion prediction model associated with fuzzy logic is a qualitative evaluation of erosive potential capable of being spatialized with a greater level of detail, increasing the traditional classification by two levels. The processing of environmental and soil conditioning factors using the fuzzy logic resulted in values between 2.5 and 9.1, which places the basin at a low to very high laminar erosion potential. The results indicate areas that demand a greater attention regarding soil management; 56.89% of the area has a medium to high laminar erosion and high to very high erosion (6.99%).


Asunto(s)
Conservación de los Recursos Naturales , Lógica Difusa , Pradera , Movimientos del Agua , Brasil , Monitoreo del Ambiente , Ríos , Suelo
2.
Eng. sanit. ambient ; Eng. sanit. ambient;22(1): 111-122, jan.-fev. 2017. graf
Artículo en Portugués | LILACS | ID: biblio-840374

RESUMEN

RESUMO Por muito tempo o exercício de atividades econômicas ocorreu na ausência de normas reguladoras. Com a normatização, muitos empreendimentos enquadraram-se em situação de irregularidade, sobretudo por ocuparem obras situadas em áreas especialmente protegidas. Nessa condição, a manutenção ou o desfazimento dessas obras deve se basear em uma análise comparativa dos impactos decorrentes de ambas as alternativas, entretanto a falta de critérios e de padronização nos procedimentos tem prejudicado o adequado tratamento e respectiva tomada de decisões. Assim, o presente trabalho teve como objetivo apresentar uma proposta metodológica para análise ambiental comparativa aplicada à adequação de empreendimentos irregulares. Para tanto, foi construído um índice global de impacto, mediante revisão bibliográfica, que possibilitou identificar os parâmetros envolvidos e o seu equacionamento com o uso de matrizes de interação. O método foi aplicado em um empreendimento que realizou intervenção em uma Área de Preservação Permanente, no limite urbano consolidado sem prévia autorização do órgão licenciador. Como resultado, alcançou-se um índice capaz de subsidiar tomadas de decisão quanto à manutenção ou ao desfazimento de empreendimentos irregulares, levando em consideração atributos como duração, extensão e intensidade no equacionamento da magnitude do impacto, bem como os parâmetros de acumulação, reversibilidade e sensibilidade para avaliar sua importância. Embora o método proposto não elimine a subjetividade da avaliação ambiental, contribui para sua padronização por meio de um procedimento lógico e organizado que propicia comparação fundamentada em parâmetros quantitativos, de maneira especial para empreendimentos de menor porte, em geral avaliados de acordo com atributos unicamente qualitativos.


ABSTRACT For a long time, economic activities occurred in the lack of legal rules. Due to advancement of legislation, many activities became in situation of irregularity, mainly by occupying buildings in protected areas. In this condition, the maintenance or destruction of these buildings should be based on an impact comparative analysis of both alternatives. However, a lack of criteria and standardization of procedures has undermined the proper treatment and decision making. Thus, the purpose of this paper was to introduce a methodological proposal for comparative environmental analysis applied to the settlement of irregular activities. For that, an impact global index was constructed, by means of literature review to identify the parameters involved, as well as to its formulation with use of interaction matrices. The method was applied for assessing an activity that made intervention in permanent preservation area, within consolidated urban area without authorization of competent agency. As a result, an index able to support making-decision about maintenance or destruction of irregular buildings was obtained, considering attributes as duration, extension and intensity in the formulation of magnitude of the impact, as well as the parameters of accumulation, reversibility and sensibility to evaluate its importance. Although the proposed method does not eliminate the subjectivity of the environmental assessment, it contributes to standardization through a logical and organized procedure that allows a comparison based on quantitative parameters, especially for smaller projects, usually assessed only according to qualitative attributes.

3.
Cad Saude Publica ; 32(5): e00021215, 2016 May.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-27192022

RESUMEN

The aim of this study was to develop a support system for the evaluation of noise pollution, applied to the central urban area of Rio Claro, São Paulo State, Brazil. Data were obtained from noise measurements and interviews with the population, generating the following indicators: equivalent sound level (Leq ), traffic noise index (LTNI ), and a participatory diagnosis (Dp ), integrated through a fuzzy inference system (FIS). The proposed system allowed classifying the measurement points according to the degree of impact of noise pollution on the population's health (IPS ) in the study area. Impact was considered significant in 31.4% of the measurement points and very significant in 62.9%. The FIS can be adjusted to local conditions, allowing generalization and thus also supporting noise pollution evaluation and respective environmental noise management in other geographic areas.


Asunto(s)
Exposición a Riesgos Ambientales/análisis , Ruido/efectos adversos , Brasil , Exposición a Riesgos Ambientales/prevención & control , Monitoreo del Ambiente , Lógica Difusa , Humanos , Ruido del Transporte/efectos adversos , Encuestas y Cuestionarios , Salud Urbana
4.
Cad. Saúde Pública (Online) ; 32(5): e00021215, 2016. tab, graf
Artículo en Portugués | LILACS | ID: lil-781575

RESUMEN

Resumo: O objetivo do trabalho foi desenvolver um sistema de apoio à avaliação da poluição sonora, aplicado na zona central de Rio Claro, São Paulo, Brasil. Para isso, dados foram obtidos por meio de medições sonoras e entrevistas com a população, gerando como indicadores o nível sonoro equivalente (Leq ), o índice de ruído de tráfego (LTNI ) e um diagnóstico participativo (Dp ), integrados por intermédio de um sistema de inferência fuzzy (SIF). Como resultado, o sistema proposto permitiu classificar os pontos avaliados quanto ao grau de impacto da poluição sonora sobre a saúde da população (IPS ) na área de estudo, que pode ser considerado significativo em 31,4% dos pontos e muito significativo em 62,9%. A possibilidade de adequar o SIF de acordo com as condições de estudo viabiliza a sua generalização e, desta forma, apoia a avaliação e respectiva gestão do ruído ambiental em outras regiões.


Resumen: El objetivo del trabajo fue desarrollar un sistema de apoyo a la evaluación de la contaminación acústica, aplicado en la zona central de Río Claro, São Paulo, Brasil. Con este fin, se obtuvieron datos mediante mediciones sonoras y entrevistas a la población, generando como indicadores el nivel sonoro equivalente (Leq ), el índice de ruido de tráfico (LTNI ) y un diagnóstico participativo (Dp ), integrados a través de un sistema de inferencia fuzzy (SIF). Como resultado, el sistema propuesto permitió clasificar los puntos evaluados, en cuanto al grado de impacto de la contaminación sonora sobre la salud de la población (IPS ) en el área de estudio, que puede ser considerado significativo en un 31,4% de los puntos y muy significativo en un 62,9%. La posibilidad de adecuar el SIF, de acuerdo a las condiciones de estudio, viabiliza su generalización y, de esta forma, puede apoyar la evaluación y consiguiente gestión del ruido ambiental en otras regiones.


Abstract: The aim of this study was to develop a support system for the evaluation of noise pollution, applied to the central urban area of Rio Claro, São Paulo State, Brazil. Data were obtained from noise measurements and interviews with the population, generating the following indicators: equivalent sound level (Leq ), traffic noise index (LTNI ), and a participatory diagnosis (Dp ), integrated through a fuzzy inference system (FIS). The proposed system allowed classifying the measurement points according to the degree of impact of noise pollution on the population's health (IPS ) in the study area. Impact was considered significant in 31.4% of the measurement points and very significant in 62.9%. The FIS can be adjusted to local conditions, allowing generalization and thus also supporting noise pollution evaluation and respective environmental noise management in other geographic areas.


Asunto(s)
Humanos , Exposición a Riesgos Ambientales/análisis , Ruido/efectos adversos , Brasil , Monitoreo del Ambiente , Salud Urbana , Encuestas y Cuestionarios , Lógica Difusa , Exposición a Riesgos Ambientales/prevención & control , Ruido del Transporte/efectos adversos
5.
Appl Radiat Isot ; 67(6): 1114-20, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19339190

RESUMEN

The common use of phosphate fertilizers NPK and amendments in sugar cane crops in Brazilian agriculture may increase the (226)Ra, (232)Th and (40)K activity concentrations in soils and their availability for plants and human food chain. Thus, the main aim of this study was to evaluate the distribution of (226)Ra, (232)Th and (40)K in soils and sugar cane crops in the Corumbataí river basin, São Paulo State, Brazil. The gamma spectrometry was utilized to measure the (226)Ra, (232)Th and (40)K activity concentration in all samples. The soil-to-sugar cane transfer factors (TF) were quantified using the ratio between the radionuclide activity concentration in sugar cane and its activity concentration in soil. The results show that, although radionuclides incorporated in phosphate fertilizers and amendments are annually added in the sugar cane crops, if utilized in accordance with the recommended rates, their use does not lead to hazards levels in soils. The soil-to-sugar cane transfer of radionuclides occurred in the following order (40)K>(226)Ra>(232)Th. Therefore, under these conditions, radionuclides intake through consumption of sugar is not hazardous to human health.


Asunto(s)
Contaminación Radiactiva de Alimentos/análisis , Saccharum , Contaminantes Radiactivos del Suelo/análisis , Agricultura , Brasil , Potasio/análisis , Radioisótopos/análisis , Radio (Elemento)/análisis , Suelo , Torio/análisis
6.
Anal Bioanal Chem ; 390(4): 1173-80, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18157665

RESUMEN

This work involved the development and application of a new analytical procedure for in-situ characterization of the lability of metal species in aquatic systems by using a system equipped with a diffusion membrane and cellulose organomodified with p-aminobenzoic acid groups (DM-Cell-PAB). To this end, the DM-Cell-PAB system was prepared by adding cellulose organomodified with p-aminobenzoic acid groups (Cell-PAB) to pre-purified cellulose bags. After the DM-Cell-PAB system was sealed, it was examined in the laboratory. The in-situ application involved immersing the DM-Cell-PAB system in two different rivers, enabling us to study the relative lability of metal species (Cu, Cd, Fe, Mn, and Ni) as a function of time and quantity of exchanger. The procedure is simple and opens up a new perspective for understanding environmental phenomena relating to the complexation, transport, stability, and lability of metal species in aquatic systems rich in organic matter.


Asunto(s)
Celulosa , Resinas de Intercambio Iónico , Metales/análisis , Agua/química , Adsorción , Sustancias Húmicas , Concentración de Iones de Hidrógeno , Espectrofotometría Atómica , Temperatura
7.
J Biol Phys ; 33(5-6): 445-53, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19669530

RESUMEN

Hydroxymethylnitrofurazone (NFOH) is active against Trypanosoma cruzi; however, its low solubility and high toxicity precludes its current use in treatment of parasitosis. Cyclodextrin can be used as a drug carrier system, as it is able to form inclusion (host-guest) complexes with a wide variety of organic (guest) molecules. Several reports have shown the interesting use of modified beta-cyclodextrins in pharmaceutical formulation, to improve the bioavailability of drugs and to decrease their toxicity. The aim of this work was to characterize inclusion complexes formed between NFOH and dimethyl-beta-cyclodextrin (DM-beta-CD) by complexation/release kinetics and solubility isotherm experiments using ultraviolet (UV)-visible spectrophotometry and by the measurement of the dynamics information obtained from T(1) relaxation times and diffusion (DOSY) experiments using nuclear magnetic resonance (NMR) spectroscopy. The complex was prepared at different NFOH and DM-beta-CD molar ratios. The UV-visible measurements were recorded in a spectrophotometer, and NMR experiments were recorded at 20 degrees C on a NMR spectrometer (Varian Inova) operating at 500 MHz. Longitudinal relaxation times were obtained by the conventional inversion-recovery method and the DOSY experiments were carried out using the BPPSTE sequence. The kinetics of complexation revealed that 30 h is enough for stabilization of the NFOH absorbance in presence of cyclodextrin. Solubility isotherm studies show a favorable complexation and increase in solubility when NFOH interacts with cyclodextrin. The analysis of the NMR-derived diffusion coefficients and T(1) relaxation times shows that in the presence of DM-beta-CD, NFOH decreases its mobility in solution, indicating that this antichagasic compound interacts with the cyclodextrin cavity. The release kinetics assays showed that NFOH changes its release profile when in the presence of cyclodextrin due to complexation. This study was focused on the physicochemical characterization of drug-delivery formulations that may serve as potentially new therapeutic options for the treatment of Chagas' disease.

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