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Rapid and uncontrolled urban growth and land use changes in watersheds worldwide have led to increased surface runoff within metropolitan areas, coupled with climate change, creating a risk for residents during the rainy season. The city of San Luis Potosí is no exception to this phenomenon. One affected watercourse is the Garita Stream, which flows inside the city near urbanization. It is essential to analyze the effects of urban sprawl on this stream based on historical precipitation data for the town. Hydrological and topographical information were required to conduct this research. The hydrological study of the basin involved analyzing the region's geomorphology and historical climatological data. For the stream's topography, aerial photogrammetry using an unmanned aerial Vehicle (UAV) and Global Navigation Satellite System (GNSS) equipment was employed to conduct topographic surveys in the area. To find out when the Garita stream would overflow and which areas are most likely to flood, numerical modeling was done using 1D, 2D, and 3D programs like SWMM5 (Storm Water Management Model), HEC-RAS (Hydrologic Engineering Center's River Analysis System), and EDFC Explorer (Environmental Fluid Dynamics Code). These models simulated different return periods and their correlation with current flooding events recorded in the area, thereby further proposing solutions to mitigate overflow issues. By conducting these simulations and analyzing the results, solutions can be suggested to address the overflow problems in the area based on historical flood events at various return periods caused by the Garita Stream.

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This paper investigates the bond behavior between a bio-aggregate and a cement-based matrix. The experimental evaluation comprised physical, chemical, image, and mechanical characterization of the bio-aggregate. The image analyses about the bio-aggregate's outer structure provided first insights to understand the particularities of this newly proposed bio-aggregate for use in cementitious materials. A mineral aggregate (granitic rock), largely used as coarse aggregate in the Brazilian civil construction industry, was used as reference. The bond behavior of both aggregates was evaluated via pull-out tests. The results indicated that both aggregates presented a similar linear elastic branch up to each respective peak loads. The peak load magnitude of the mineral aggregate indicated a better chemical adhesion when compared to the bio-aggregate's. The post-peak behavior, however, indicated a smoother softening branch for the bio-aggregate, corroborated by the microscopy image analyses. Although further investigation is required, the macaúba crushed endocarp was found to be a thriving bio-material to be used as bio-aggregate.

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ABSTRACT Improper design and management of the cover layer of a sanitary landfill has been proven to produce harmful environmental impacts on the environment. One alternative at hand is to develop scenarios based on simulation of physical and computational models to represent the expected field water balance of a landfill coverage layer. This paper investigates the design of a sanitary landfill final cover in the municipality of Seropédica, which is located at the state of Rio de Janeiro - Brazil. More specifically, the compact soil coverage, which is widely used for landfill final cover of municipal solid waste, is evaluated in contrast to vegetation cover by grass, vegetation cover by brachiaria and capillary barrier. To accomplish such task, hydrometeorological forcing conditions, namely daily rainfall and temperature, were retrieved from the Anchieta weather station, which is situated nearby the study area. The Hydrus 1D and 2/3 D computational codes were employed to develop a set of scenarios to follow the contamination plume evolution within the landfill along the time frame of 20 years with some degree of reliability. It should be noted that the performed evaluation indicates the possibility to control the leachate release and consequently to avoid contaminating the environment, notably to prevent soil and water resources pollution. Vegetation cover by grass and brachiaria showed important control mechanisms with respect to the movement of the contaminant plume. In addition, it should be noticed that the best results for the landfill final cover were achieved for the capillary barrier, while poor performance results were obtained for the commonly employed compact soil.

RESUMO O projeto e a gestão inadequados da camada de cobertura de um aterro sanitário produzem impactos ambientais prejudiciais ao meio ambiente. Uma alternativa disponível é desenvolver cenários baseados na simulação de modelos físicos e computacionais para representar o balanço hídrico que se espera que ocorra em uma camada de cobertura do aterro por meio de um experimento de campo. O presente trabalho investiga o projeto de cobertura final de um aterro sanitário no município de Seropédica, localizado no estado do Rio de Janeiro - Brasil. Mais especificamente, a cobertura compacta do solo, que é amplamente utilizada para a cobertura final de aterro de resíduos sólidos urbanos, é avaliada em contraste com a cobertura vegetal por gramíneas, cobertura vegetal por braquiária e barreira capilar. Para realização dessa tarefa, forçantes hidrometeorológicas, nomeadamente precipitação e temperatura na escala diária, foram obtidas da estação meteorológica de Anchieta, situada nas proximidades da área de estudo. Os códigos computacionais Hydrus 1D e 2/3 D foram empregados para desenvolver um conjunto de cenários para acompanhar a evolução da pluma de contaminação no interior do aterro ao longo do período de 20 anos com algum grau de confiabilidade. Ressalta-se que a avaliação realizada indica a possibilidade de controlar a liberação de chorume e, consequentemente, de evitar a contaminação do meio ambiente, notadamente para prevenir a poluição do solo e dos recursos hídricos. A cobertura vegetal por gramíneas e braquiárias apresentou importantes mecanismos de controle com relação ao movimento da pluma contaminante. Além disso, deve-se notar que os melhores resultados para a cobertura final do aterro foram alcançados para a barreira capilar, enquanto que os resultados de baixo desempenho foram obtidos para o solo compacto comumente empregado.

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According to experts and medical literature, healthy thyroids and thyroids containing benign nodules tend to be less inflamed and less active than those with malignant nodules. It seems to be a consensus that malignant nodules have more blood veins and more blood circulation. This may be related to the maintenance of the nodule's heat at a higher level compared with neighboring tissues. If the internal heat modifies the skin radiation, then it could be detected by infrared sensors. The goal of this work is the investigation of the factors that allow this detection, and the possible relation with any pattern referent to nodule malignancy. We aim to consider a wide range of factors, so a great number of numerical simulations of the heat transfer in the region under analysis, based on the Finite Element method, are performed to study the influence of each nodule and patient characteristics on the infrared sensor acquisition. To do so, the protocol for infrared thyroid examination used in our university's hospital is simulated in the numerical study. This protocol presents two phases. In the first one, the body under observation is in steady state. In the second one, it is submitted to thermal stress (transient state). Both are simulated in order to verify if it is possible (by infrared sensors) to identify different behavior referent to malignant nodules. Moreover, when the simulation indicates possible important aspects, patients with and without similar characteristics are examined to confirm such influences. The results show that the tissues between skin and thyroid, as well as the nodule size, have an influence on superficial temperatures. Other thermal parameters of thyroid nodules show little influence on surface infrared emissions, for instance, those related to the vascularization of the nodule. All details of the physical parameters used in the simulations, characteristics of the real nodules and thermal examinations are publicly available, allowing these simulations to be compared with other types of heat transfer solutions and infrared examination protocols. Among the main contributions of this work, we highlight the simulation of the possible range of parameters, and definition of the simulation approach for mapping the used infrared protocol, promoting the investigation of a possible relation between the heat transfer process and the data obtained by infrared acquisitions.

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We modeled Group A Rotavirus (RVA) and Norovirus genogroup II (GII NoV) transport experiments in standardized (crystal quartz sand and deionized water with adjusted pH and ionic strength) and natural soil matrix-water systems (MWS). On the one hand, in the standardized MWS, Rotavirus and Norovirus showed very similar breakthrough curves (BTCs), showing a removal rate of 2 and 1.7 log10, respectively. From the numerical modeling of the experiment, transport parameters of the same order of magnitude were obtained for both viruses. On the other hand, in the natural MWS, the two viruses show very different BTCs. The Norovirus transport model showed significant changes; BTC showed a removal rate of 4 log10, while Rotavirus showed a removal rate of 2.6 log10 similar to the 2 log10 observed on the standardized MWS. One possible explanation for this differential behavior is the difference in the isoelectric point value of these two viruses and the increase of the ionic strength on the natural MWS.

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The damage of coastal infrastructure due to wave action has stimulated the need for vulnerability assessments for integrated coastal management. Vulnerability is described as the ability of people living in an area to anticipate, cope with, resist and recover from the impact produced by a coastal hazard. This study aims to develop a multi-criteria index to assess coastal vulnerability to waves. Therefore, we analyze the Santa Catarina State (southern Brazil) coastline vulnerability to the incident wave climate. The applied coastal vulnerability index (CVI) was obtained by integrating the adaptive capacity index (ACI), composed of socioeconomic and locational variables, and the susceptibility index (SI), composed of physical variables. The resulting coastal dynamics from nearshore wave processes were analyzed through numerical models and integrated with other variables in a geographic information system (GIS). The relevance of the variables to the index was obtained by the analytic hierarchy process (AHP). The variables and indices were hierarchized into five vulnerability classes and represented in the administrative sectors defined by the local State Coastal Management Plan. Based on the AHP results, the physical variables were considered more relevant than the socioeconomic and locational variables. In general, the southern portion of the state presented higher susceptibility degrees, a lower income per capita and a lower number of second residences than the northern portion. At the same time, the northern portion presented higher percentages of developed areas, which are predominantly situated along susceptible and vulnerable segments. The numerical modeling of wave propagation has a large impact on the vulnerability as a function of the higher weights assigned to the related variables by experts and the high variability of the significant wave height along the state's coastline. Our results emphasize the importance of the inclusion of physical variables, such as waves, when defining coastal management measures in coastal zones.

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The Estuarine-Lagoon Complex of Cananeia-Iguape (ELCCI) is a large estuarine system dominated by mangroves, located on the southeast coast of Brazil (25° S, 48° W). Oyster farming is an important economic activity in Cananeia due to the natural abundance of oyster seeds originally found in its mangrove fields. The aim of this study was to describe the hydrodynamic aspects of the mangrove and oyster farming in the ELCCI by analyzing environmental scenarios using numerical simulations. Simulations allowed for the description of the distance of penetration of the salt wedge into the system as well as the direction and magnitude of the tidal currents. Higher values of river discharge corresponded to lower distances of penetration of the salt wedge, a feature which shows that the freshwater discharge and geomorphology together determine the variation in salinity within the estuary. Oysters are cultivated in regions of higher salinity and relatively stable conditions, with low speeds of tidal currents and little vertical variation in salinity. Under average river discharge conditions (450 m3.s-1), there is a confluence of tidal waves in Mar Pequeno, where velocity is lower. This change may lead to a higher sedimentation at restricted areas and thus to a higher deposition of organic matter derived from oyster cultivations during flood tides.

O Complexo Estuarino Lagunar de Cananeia-Iguape (CELCI) é um grande estuário dominado por sistemas de mangues, os quais são encontrados na costa sudeste do Brasil (25° S, 48° W). A ostreicultura é uma importante atividade econômica em Cananeia devido à abundância natural de sementes de ostras que são encontradas originalmente em seus campos de mangue. O objetivo deste estudo foi descrever os aspectos hidrodinâmicos do mangue e das áreas de cultivo de ostras no CELCI analisando-se cenários ambientais de simulações numéricas. As simulações permitiram a descrição da distância de penetração da cunha salina no sistema, assim como da direção e a magnitude das correntes de maré. Valores mais elevados da descarga dos rios corresponderam a uma menor distância de penetração da cunha salina, mostrando que a descarga de água doce e a geomorfologia juntos determinam a variação na salinidade dentro do estuário. As ostras são cultivadas em regiões de maior salinidade e condições relativamente estáveis, com baixas velocidades das correntes de maré e pouca variação vertical da salinidade. Sob condições de descarga média (450 m3.s-1), há um encontro de ondas de maré na localidade do Mar Pequeno, onde a velocidade de corrente é menor. Essa mudança pode levar a uma maior sedimentação em áreas restritas e, portanto, a uma maior deposição de matéria orgânica derivada de cultivo de ostra durante a maré enchente.

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The Estuarine-Lagoon Complex of Cananeia-Iguape (ELCCI) is a large estuarine system dominated by mangroves, located on the southeast coast of Brazil (25° S, 48° W). Oyster farming is an important economic activity in Cananeia due to the natural abundance of oyster seeds originally found in its mangrove fields. The aim of this study was to describe the hydrodynamic aspects of the mangrove and oyster farming in the ELCCI by analyzing environmental scenarios using numerical simulations. Simulations allowed for the description of the distance of penetration of the salt wedge into the system as well as the direction and magnitude of the tidal currents. Higher values of river discharge corresponded to lower distances of penetration of the salt wedge, a feature which shows that the freshwater discharge and geomorphology together determine the variation in salinity within the estuary. Oysters are cultivated in regions of higher salinity and relatively stable conditions, with low speeds of tidal currents and little vertical variation in salinity. Under average river discharge conditions (450 m3.s-1), there is a confluence of tidal waves in Mar Pequeno, where velocity is lower. This change may lead to a higher sedimentation at restricted areas and thus to a higher deposition of organic matter derived from oyster cultivations during flood tides.(AU)

O Complexo Estuarino Lagunar de Cananeia-Iguape (CELCI) é um grande estuário dominado por sistemas de mangues, os quais são encontrados na costa sudeste do Brasil (25° S, 48° W). A ostreicultura é uma importante atividade econômica em Cananeia devido à abundância natural de sementes de ostras que são encontradas originalmente em seus campos de mangue. O objetivo deste estudo foi descrever os aspectos hidrodinâmicos do mangue e das áreas de cultivo de ostras no CELCI analisando-se cenários ambientais de simulações numéricas. As simulações permitiram a descrição da distância de penetração da cunha salina no sistema, assim como da direção e a magnitude das correntes de maré. Valores mais elevados da descarga dos rios corresponderam a uma menor distância de penetração da cunha salina, mostrando que a descarga de água doce e a geomorfologia juntos determinam a variação na salinidade dentro do estuário. As ostras são cultivadas em regiões de maior salinidade e condições relativamente estáveis, com baixas velocidades das correntes de maré e pouca variação vertical da salinidade. Sob condições de descarga média (450 m3.s-1), há um encontro de ondas de maré na localidade do Mar Pequeno, onde a velocidade de corrente é menor. Essa mudança pode levar a uma maior sedimentação em áreas restritas e, portanto, a uma maior deposição de matéria orgânica derivada de cultivo de ostra durante a maré enchente.(AU)

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Population pressure, urbanization, and industrial developments, among other factors, have resulted in severe degradation of environmental resources such as wetlands. Thus, a groundwater model (MODFLOW) was integrated with a particle tracking MODPATH model to simulate the hydrodynamic flow head field and to analyze the vulnerability of the Salburua ecosystem and propose control measures to protect the riparian area. The simulations show that pathways of particle tracking originating at potential contaminant sources will tend to migrate downwards towards the sensitive ecosystem, which suggests that the quality of the hydrological ecosystem is likely to deteriorate in the future. Variation in exit points of particles indicates that the time-related capture areas are affected by changes of the hydraulic gradients. Two control measures of potential sources of pollutants in the vicinity of the Salbarua ecosystem were analyzed. The study results suggest that the travel time-related capture zone with a funnel-and-gate system is much smaller than without the control alternative, which indicates that the gate configuration has an effect on capture zone size and shape and on the residence time with a better attenuation performance. It is also shown that a leakage-proof barrier is less effective for point-source containment, assuming that hydraulic control performance and cost-efficiency are the criteria for pollution control effectiveness. Instead, a program of monitoring wells would effectively characterize water quality in the aquifer and provide a decision support system. This approach may be used in helping water managers to develop more physically based and quantitative protection strategies.

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Palmeras (Gorgona National Park) is one of the most important sites for sea turtle nesting in South and Central America. Because of the morphological processes affecting the beach, the turtle nests are increasingly exposed to the impact of waves and tides, threatening conservation. A study was made to determine the hydrodynamical processes of the zone adjacent to Playa Palmeras, which affects directly the morphodynamical behavior of the beach and thus the preservation of the nests. Field measurements and numerical modeling were used to obtain the general circulation patterns and thermohaline structure behavior in the area in order to determine the spatial and temporal variability of waves and its effects on the beach. A marked seasonality was found, both in the waves and the currents, influenced mainly by the meridional displacement of the ITCZ (Inter-Tropical Convergence Zone) and an interannual variability of the waves, associated with ENSO (El Niño Southern Oscillation). The flooding levels of the beach were determined and flooding probability maps were made, where safer sites to locate the turtle nests could be identified. These maps serve the officials responsible of monitoring the turtles as a tool to take decisions on moving the nests, since they have flood risk information for any point on the beach. The results show that the middle zone north of the beach is the one with the lowest risk of flooding, therefore the most appropriate zone to relocate nests that are in high risk areas. Rev. Biol. Trop. 62 (Suppl. 1): 133-147. Epub 2014 February 01.

Playa Palmeras (En el Parque Nacional Isla Gorgona) es uno de los sitios más importantes para la anidación de tortugas marinas en América del Sur y Centroamérica. Debido a procesos morfológicos que afectan la playa, los nidos de las tortugas se han visto cada vez más expuestos al impacto del oleaje y la marea, poniendo en riesgo la conservación de éstas especies. Se llevó a cabo un estudio para conocer los procesos hidrodinámicos de la zona costera en Playa Palmeras, de los cuales depende el comportamiento morfodinámico de la playa y la preservación de los nidos. Se usó modelación numérica y mediciones en campo para conocer la variabilidad espacio-temporal del oleaje y obtener los patrones generales de circulación y la estructura termohalina de la zona. Se encontró un marcado ciclo anual, tanto en el oleaje como en las corrientes, influenciado por la Zona de Convergencia Intertropical (ZCIT) y una variabilidad interanual del oleaje, asociada a El Niño Oscilación del Sur (ENSO). Se estimó la cota de inundación de la playa y se crearon mapas de probabilidad de inundación, identificando los sitios potencialmente más seguros para la anidación. Los resultados muestran que hacia el norte de la playa está la zona de menor riesgo.

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Using numerical modeling, this work estimates sediment dispersion patterns caused by the incidence of waves in five distinct coastline contours of the Jequitinhonha River delta plain during the Late Holocene. For this study, a wave cliate odel based on the construction of ave refraction diagras relative to the current boundary conditions as defined and assumed to be valid for the five coastlines. Numerical modeling from the refraction diagrams was carried out considering the angle of incidence and wave height along the coastline. This work has allowed us to reproduce past and current patterns of net longshore sediment drift defined by a conceptual model developed from the integration of sediment cores, aerial photograph interpretation, C14 datings and geomorphic indicators of longshore drift. These results show that, on average, current wave conditions in the east-northeastern Brazilian region seem to have remained characteristically the same from approximately 5100 years BP until the present time. This type of information can be important when attempting to simulate possible future situations in terms of the long-term general behavior of the east-northeastern Brazilian coastal region.

O presente trabalho apresenta uma estimativa, por modelagem numérica, dos padrões de dispersão de sedimentos causados pela incidência de ondas em cinco distintos contornos de linhas de costa da planície deltaica do Rio Jequitinhonha durante o Holoceno Tardio. Para isso, um modelo de clima de ondas baseado na construção de diagramas de refração de onda, em função das condições de contorno atuais, foi definido e assumido ser válido para as cinco linhas de costa. A modelagem numérica, a partir dos diagramas de refração, foi feita considerando o ângulo de aproximação e a altura da onda ao longo da linha de costa. O trabalho permitiu reproduzir os padrões pretéritos e atuais da deriva litorânea efetiva de sedimentos, definidos por um modelo conceitual desenvolvido a partir da integração de testemunhos de sedimentos, interpretação de fotos aéreas e datações de C14, bem como por indicadores geomórficos de deriva. Estes resultados mostram que, em média, em relação à região leste-nordeste brasileira as condições de onda atuais parecem ter permanecido com as mesmas características desde aproximadamente 5.100 anos A.P. até o tempo atual. Esse tipo de informação pode ser importante para tentativas de simulação de possíveis situações futuras em termos do comportamento genérico de longa duração das regiões costeiras leste-nordeste brasileira.

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O objetivo deste estudo é avaliar o modelo de previsão numérica do tempo BRAMS (Brazilian Regional Atmospheric Modelling System), a partir da comparação entre os valores preditos e os observados (dados do NCEP/NOAA (National Centers of Environmental Predictions/ National Oceanic and Atmospheric Administration) e do satélite TRMM (Tropical Rainfall Measuring Mission)). O modelo foi assimilado com dados do modelo global do NCEP/NOAA e do CPTEC/INPE. Foram realizadas comparações entre os valores preditos e os observados através da raiz do erro quadrático médio (RMSE) e do erro médio (ME) para os prognósticos de precipitação para os horizontes de 24, 48, 72 e 96 horas, do período de novembro de 2008 a março de 2009. Os resultados mostraram que o modelo BRAMS teve uma performance melhor quando assimilado com dados do modelo global do NCEP/NOAA comparado com as saídas a partir das assimilações do modelo global do CPTEC/INPE.

The objective of this study is to evaluate the model of numerical forecast BRAMS (Brazilian Regional Atmospheric Modelling System) from the comparison between the forecast and observed rainfall (data of NCEP/NOAA (National Centers of Environmental Predictions/ National Oceanic and Atmospheric Administration) and of TRMM satellite (Tropical Rainfall Measuring Mission)). The model used the initial conditions of global model of NCEP/NOAA e do CPTEC/INPE. Comparisons between predicted values and observed through were the root medium square error (RMSE) and of medium error (ME) for the forecast of rainfall of 24, 48, 72 and 96 hours, of the period November of 2008 to March of 2009. The results showed that the BRAMS model had better performance when treated with global model data from NCEP / NOAA compared with the outputs from the assimilation of the global model of CPTEC / INPE.

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The objective of this study is to evaluate the model of numerical forecast BRAMS (Brazilian Regional Atmospheric Modelling System) from the comparison between the forecast and observed rainfall (data of NCEP/NOAA (National Centers of Environmental Predictions/ National Oceanic and Atmospheric Administration) and of TRMM satellite (Tropical Rainfall Measuring Mission)). The model used the initial conditions of global model of NCEP/NOAA e do CPTEC/INPE. Comparisons between predicted values and observed through were the root medium square error (RMSE) and of medium error (ME) for the forecast of rainfall of 24, 48, 72 and 96 hours, of the period November of 2008 to March of 2009. The results showed that the BRAMS model had better performance when treated with global model data from NCEP / NOAA compared with the outputs from the assimilation of the global model of CPTEC / INPE.

O objetivo deste estudo é avaliar o modelo de previsão numérica do tempo BRAMS (Brazilian Regional Atmospheric Modelling System), a partir da comparação entre os valores preditos e os observados (dados do NCEP/NOAA (National Centers of Environmental Predictions/ National Oceanic and Atmospheric Administration) e do satélite TRMM (Tropical Rainfall Measuring Mission)). O modelo foi assimilado com dados do modelo global do NCEP/NOAA e do CPTEC/INPE. Foram realizadas comparações entre os valores preditos e os observados através da raiz do erro quadrático médio (RMSE) e do erro médio (ME) para os prognósticos de precipitação para os horizontes de 24, 48, 72 e 96 horas, do período de novembro de 2008 a março de 2009. Os resultados mostraram que o modelo BRAMS teve uma performance melhor quando assimilado com dados do modelo global do NCEP/NOAA comparado com as saídas a partir das assimilações do modelo global do CPTEC/INPE.