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Desenvolvimento e aplicação de procedimentos envolvendo reações quimiluminescentes em fluxo para a determinação de analitos de interesse alimentício, farmacêutico e bioquímico
(Universidade Federal de São Carlos, 2005-09-23) Leite, Oldair Donizeti; Fatibello Filho, Orlando; https://lattes.cnpq.br/9859737944357808
In this work, analytical flow procedures were developed using multicommutation concept and chemiluminescent detection for the determination of hydrogen peroxide, glucose and cholesterol in food, biochemistry and pharmaceutical samples. A personal computer Pentium 233 MHz equipped with PCL 711S interface was employed to control the flow manifold and data acquisition. The detection module consist of a flow-cell constructed with a coiled polyethylene tubing (0.8 mm i.d.), a silicon photodiode (OSD-50E) and an electronic device (model FAC 500) for signals conditioning and amplification, are devices were placed in a dark box. The manifold and detection module were characterized by hydrogen peroxide determination in pharmaceutical samples, monitoring the radiation produced in the chemiluminescent reaction between luminol, H2O2 and hexacyanoferrate(III). The analytical curve obtained was linear in the hydrogen peroxide concentration ranging from 2.2 x 10-6 to 2.1 x 10-4 mol L-4 and the detection limit obtained was 1.8 x 10-6 mol L-1. In the procedures for glucose determination in food, pharmaceutical and biochemical samples, a solid-phase reactor containing glucose oxidase immobilized in glass beads was employed. The hydrogen peroxide generated in this enzymatic reaction was monitored by chemiluminescent emission produced by the luminol/hexacyanoferrate(III) reaction. The proposed procedure showed linear response from 5.0 to 160.0 mg L-1 and a sampling rate of 160 samples per hour was obtained. The analytical procedure was employed with success in the glucose determination in honey, glucose pharmaceutical formulation, grape and tomato juices. For glucose determination in blood serum, the manifold was reconfigured to minimize the sample manipulation. The results obtained in the glucose determination in serum using this proposed procedure are in close agreement with those obtained using the comparative procedure at a confidence level of 95%. In the proposed procedure for cholesterol determination in eggs a solid-phase reactor containing immobilized cholesterol oxidase was used, the hydrogen peroxide produced was monitored by the same chemiluminescent reaction. The linear range of analytical curve obtained in optimized procedure ranged from 250 to 2500 mg L-1, and are described by the equation: Intensity (mV)= 43.0 + 0.325 x [cholesterol], r= 0.999, The luminol and hexacyanoferrate(III) consumption per determination were 356 µg and 2.64 mg, respectively. The manifold was reconfigured for cholesterol determination in serum. The results obtained were in agreement with those obtained using the comparative procedure. Extraction and pre-purification of enzyme peroxidase were carried out with the purpose of employing this enzyme as a catalyst in the chemiluminescent reaction between the luminol and hydrogen peroxide.
Restauração de imagens de microscopia confocal utilizando técnicas POCS
(Universidade Federal de São Carlos, 2005-09-23) Stelzer, Murilo; Mascarenhas, Nelson Delfino d'Ávila; https://lattes.cnpq.br/0557976975338451
Computer Optical Sectioning Microscopy (COSM) is widely used in morphological studies of cellular structures. COSM appears as a great challenge to digital image processing, because the large size of the three-dimensional files. The major problem in COSM is the blurring, which practically turn the image unusable without the use of digital image processing techniques. In this work, based on projection onto convex set were developed image processing techniques to restore COSM images, obtained by a confocal microscope. Although confocal microscope presents less blurring than the wide field microscope, it has a larger Poisson noise level. To reduce the Poisson noise the Anscombe Transform (AT) was used as well a pointwise Wiener Filter. The POCS methods were evaluated by means of simulations, using synthetic images (phantom), and the results was evaluated by ISNR (Improvement in Signal Noise Ratio) and UIQ (Universal Quality Index). The developed algorithms, using RAP (Row Action Projection) present satisfactory results, but the computational costs were expensive.
Relações entre as variáveis edáficas e vegetacionais em cerrado hiperestacional, cerrado estacional e campo úmido no Parque Nacional das Emas (GO)
(Universidade Federal de São Carlos, 2005-09-23) Amorim, Priscilla Kobayashi; Batalha, Marco Antônio Portugal Luttembarck; https://lattes.cnpq.br/3893228815181339
The Cerrado Domain occupied formerly 2 million km2 of the Brazilian territory, especially in the Central Plateau. The cerrado vegetation is not uniform in physiognomy, ranging from grassland to tall woodland, but with most of its physiognomies within the range defined as tropical savanna. In cerrado, there are few areas that become waterlogged during the rainy season due to the poor drainage of the soil, allowing the appearance of a hyperseasonal cerrado, characterized by two contrasting stresses, one induced by drought and fire during the winter, the other by soil saturation in the summer. As long as soil is important in the ecology of the cerrado, limiting the cerrado distribution and the occurrence of its physiognomies, we investigated the soil-vegetation relationships in a cerrado core area in Emas National Park, in three vegetation forms: hyperseasonal cerrado, seasonal cerrado, and wet grassland. We collected vegetation and soil samples in these three vegetation forms and submitted obtained data to a canonical correspondence analysis. Our results showed a distinction among hyperseasonal cerrado, seasonal cerrado and wet grassland, which presented different floristic compositions and species abundances. The edaphic variables best related to the hyperseasonal and seasonal cerrados were sand, base saturation, pH, and magnesium. The wet grassland was related to higher concentrations of clay, organic matter, aluminium saturation, aluminium, phosphorus, and potassium. We also investigated the relationships between number of species and soil characteristics, with simple multiple linear regressions, and found that aluminium and pH were the best predictors of species density, the former positively related to species density and the latter negatively related.
Aplicação do indicador de proximidade de áreas verdes urbanas na cidade de Jaboticabal - SP
(Universidade Federal de São Carlos, 2005-09-23) Russo, Renato Anselmo; Teixeira, Bernardo Arantes do Nascimento; https://lattes.cnpq.br/1166854416745527
Several studies have been done with urban green areas used as indicators of the sustainability in the Environmental Planning of a city. The current study aimed to apply an indicator of sustainability to central green areas of Jaboticabal city (state of São Paulo) and to interpret its behavior. For this, a characterization of these green areas, which areas located in the urban perimeter of the city, was made citing its measures, type of use, conservation conditions, location and vegetation. The chosen indicator, which is the same to other identified experiences, was the Green Area Proximity Index (IPAV), considering 300 or 500 meter distances. The IPAV enables the adoption of a graphic instrument for its calculation and analysis. The developing of graphic instruments related to the chosen indicators increases the number of interpretations which can also be used for other studies. The result obtained with the used of IPAV has raised questions regarding its efficiency, when applied in isolation, because it can interfere in the value of other indicators. However the IPAV is a valuable tool to help in the distribution of the green areas inside the urban region. The main idea is that this study may contribute as a tool to the Environmental Planning of a city, along with Sustainable Urbanization, resulting in a better quality of life for people. This scientific contribution is intended to give support to pertinent actions to our reality without jeopardizing future situations.
Alterações bioquímicas e cardio-respiratórias de Tilápia do Nilo (Oreochromis niloticus) frente à exposição sub-letal ao sulfato de cobre
(Universidade Federal de São Carlos, 2005-09-23) Neder, Lyandra Mara Zanatta; Rantin, Francisco Tadeu; https://lattes.cnpq.br/3546242299713690
The present study evaluated the biochemical, hematological and cardio-respiratory responses of Nile tilapia (Oreochromis niloticus) to copper sulfate (CuSO4). A group of fish (T2; n = 8) was exposed to 50% of a CL50 (48 h) of CuSO4, while the control group (T1; n = 8) was submitted to the same conditions of water quality without CuSO4. Samples of blood, gills, liver, white and red muscles were collected at the end of the experimental period for the following determination: Hematocrit (Hct), hemoglobin (Hb), red blood cells (RBC), mean corpuscular volume (VCM), mean corpuscular hemoglobin (HCM), mean corpuscular hemoglobin concentration (CHCM), Na+/K+-ATPase, metalothionein (MT), glucose, lactate, pyruvate, glycogen, ionic concentrations (Na+, K+ e Cl-) and plasmatic ammonia. The cardio-respiratory parameters (oxygen uptake - &VO2 , O2 extraction from the ventilatory current - EO2, respiratory frequency - fR, gill ventilation - &VG , ventilatory tidal volume - VT, and heart rate - fH). were also measured in both experimental groups during 48 h: When compared to the control group, fish treated with CuSO4 showed a significant increase in Hct, Hb, RBC and VCM. Lactate concentration increased in liver and red muscle. Glucose increased also in liver, but decreased in the muscles, and a reduction on glycogen was observed in all the tissues analyzed. Fish exposed to CuSO4 presented a reduction in EO2 after 3 h and in &VO2 after 6 h. An increase in &VG was detected after 1 h of exposure to CuSO4. This hiperventilation was mainly due to increases in the fR, since the VT remained constant during all the experimental time. Fish treated with CuSO4 also displayed a significant bradycardia after 12 hours of exposure.