Water quality monitoring by nanostructured films in a sensing unit system

Presented here is a study about the capability of a sensing unit to detect changes in river water quality. In order to determine its accuracy, water quality was monitored at 11 points along the Veado River in Presidente Prudente, Brazil. To have a basis for comparison, a water quality index (WQI) was developed following methods previously applied in different watersheds. Results showed an accurate relationship between WQI and electric impedance readings detected by the sensing unit. Principal components analysis (PCA) was used to derive results in a form that can be correlated with WQI calculated for each sample point, which showed the potential application of this device.

An hydrochemical answer to a legislative demand involving health risk related to water quality

Effluents and surface waters around an area involved with the inking of tissues at Itatiba municipality, São Paulo State, Brazil, were chemically analyzed with the purpose of evaluating the influence on the water quality of the chemicals released, as well to provide answers to legislative requirements related to the São Paulo State Register 997 published on 31 May 1976.

Management of vomplex systems: Modeling the biological pest control

The aim of this paper is to study the cropping system as complex one, applying methods from theory of dynamic systems and from the control theory to the mathematical modeling of the biological pest control. The complex system can be described by different mathematical models. Based on three models of the pest control, the various scenarios have been simulated in order to obtain the pest control strategy only through natural enemies' introduction. © 2008 World Scientific Publishing Company.

Water quality in six sequentially disposed fishponds with continuous water flow

This study evaluated selected limnological variables in inlet water in six sequentially distributed semi-intensive fishponds. Data were collected during 15 consecutive days in three distinct grow-out periods (May, October and January). Only phosphorus and pH varied among sites and periods (p < 0.01); the opposite (p > 0.05) occurred in the cases of nitrite and dissolved oxygen. No variation was reported with regard to dissolved oxygen, conductivity, alkalinity, free CO2, bicarbonate, chlorophyll-a, nitrite and ammonia did not vary throughout the period (p > 0.05). In May, or rather, the final grow-out period, the fishponds displayed high concentrations, mainly in nitrogen compounds. As from fishpond 3, the inlet water contained high levels of nutrients. The water is passed from pond to pond, evidencing the need for management practices adequate to the specific conditions of each pond. Water quality should be monitored more frequently during high grow-out period when food addition is more intense. Thereafter, more care should be taken, as highest phosphorus concentrations occurred in May.

Tridimensional modeling of the cardiac wall

The advance in the graphic computer's techniques and computer's capacity of processing made possible applications like the human anatomic structures modeling, in order to investigate diseases, surgical planning or even provide images for training of Computer Aided Diagnosis (CAD). On this context, this work exhibits an anatomical model of cardiac structures represented in a tridimensional environment. The model was represented with geometrical elements and has anatomical details, as the different tunics that compose the cardiac wall and measures that preserves the characteristics found on real structures. The validation of the anatomical model was made through quantitative comparations with real structures measures, available on specialized literature. The results obtained, evaluated by two specialists, are compatible with real anatomies, respecting the anatomical particularities. This degree of representation will allow the verification of the influence of radiological parameters, morphometric peculiarities and stage of the cardiac diseases on the quality of the images, as well as on the performance of the CAD. © 2010 IEEE.

Determination of the quality index of a Paleudult under sunflower culture and different management systems

Soil is an essential resource for life and its properties are susceptible to be modified by tillage systems. The impact of management practices on soil functions can be assessed through a soil quality index. It is interesting to assess soil quality in different soil types. Therefore, the aim of this study was to determine the soil quality index of a Paleudult under different management conditions and sunflower culture. The experiment was carried out in Botucatu (SP, Brazil), in an 11-year non-tilled area used for growing soybean and maize during summer and black oat or triticale in winter. Four management systems were considered: no-tillage with a hoe planter (NTh), no-tillage with a double-disk planter (NTd), reduced tillage (RT) and conventional tillage (CT). Soil samples were taken from the planting lines at harvest time. To determine the soil quality indices, following the methodology proposed by Karlen and Stott (1994), three main soil functions were assessed: soil capacity for root development, water storage capacity of the soil and nutrient supply capacity of the soil. The studied Paleudult was considered a soil with good quality under all the observed management systems. However, the soil quality indices varied between treatments being 0.64, 0.68, 0.86 and 0.79 under NTh, NTd, RT and CT, respectively. Physical attributes such as resistance to penetration and macroporosity increased the soil quality index in RT and CT compared to NTh and NTd. The soil quality indices obtained suggested that the evaluated soil is adequate for sunflower production under our study conditions. In view of the SQI values, RT is the most suitable management for this site since it preserves soil quality and provides an acceptable sunflower yield. © 2011 Elsevier B.V.

Free tools and strategies for the generation of 3D finite element meshes: Modeling of the cardiac structures

The Finite Element Method is a well-known technique, being extensively applied in different areas. Studies using the Finite Element Method (FEM) are targeted to improve cardiac ablation procedures. For such simulations, the finite element meshes should consider the size and histological features of the target structures. However, it is possible to verify that some methods or tools used to generate meshes of human body structures are still limited, due to nondetailed models, nontrivial preprocessing, or mainly limitation in the use condition. In this paper, alternatives are demonstrated to solid modeling and automatic generation of highly refined tetrahedral meshes, with quality compatible with other studies focused on mesh generation. The innovations presented here are strategies to integrate Open Source Software (OSS). The chosen techniques and strategies are presented and discussed, considering cardiac structures as a first application context. © 2013 E. Pavarino et al.

Performance Analysis of MODIS 500-m Spatial Resolution Products for Estimating Chlorophyll-a Concentrations in Oligo-to Meso-Trophic Waters Case Study: Itumbiara Reservoir, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Inverse Modeling of GPS Multipath for Snow Depth Estimation-Part I: Formulation and Simulations

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Inverse Modeling of GPS Multipath for Snow Depth Estimation-Part II: Application and Validation

GPS multipath reflectometry (GPS-MR) is a technique that uses geodetic quality GPS receivers to estimate snow depth. The accuracy and precision of GPS-MR retrievals are evaluated at three different sites: grasslands, alpine, and forested. The assessment yields a correlation of 0.98 and an rms error of 6-8 cm for observed snow depths of up to 2.5 m. GPS-MR underestimates in situ snow depth by 10%-15% at these three sites, although the validation methods do not measure the same footprint as GPS-MR.

Measurements and modeling of reactive nitrogen deposition in southeast Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Organic farm does not improve neither soil, or water quality in rural watersheds from southeastern Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Does the plankton community follow the horizontal water quality heterogeneity in a tropical urban reservoir (Guarapiranga reservoir, Sao Paulo, Brazil)?

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Water quality and communities associated with macrophytes in a shallow water-supply reservoir on an aquaculture farm

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)