977 resultados para sensibilidade


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Aiming to consumer s safety the presence of pathogenic contaminants in foods must be monitored because they are responsible for foodborne outbreaks that depending on the level of contamination can ultimately cause the death of those who consume them. In industry is necessary that this identification be fast and profitable. This study shows the utility and application of near-infrared (NIR) transflectance spectroscopy as an alternative method for the identification and classification of Escherichia coli and Salmonella Enteritidis in commercial fruit pulp (pineapple). Principal Component Analysis (PCA), Independent Modeling of Class Analogy (SIMCA) and Discriminant Analysis Partial Least Squares (PLS-DA) were used in the analysis. It was not possible to obtain total separation between samples using PCA and SIMCA. The PLS-DA showed good performance in prediction capacity reaching 87.5% for E. coli and 88.3% for S. Enteritides, respectively. The best models were obtained for the PLS-DA with second derivative spectra treated with a sensitivity and specificity of 0.87 and 0.83, respectively. These results suggest that the NIR spectroscopy and PLS-DA can be used to discriminate and detect bacteria in the fruit pulp

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Soil contamination by pesticides is an environmental problem that needs to be monitored and avoided. However, the lack of fast, accurate and low cost analytical methods for discovering residual pesticide in complex matrices, such as soil, is a problem still unresolved. This problem needs to be solved before we are able to assess the quality of environmental samples. The intensive use of pesticides has increased since the 60s, because the dependence of their use, causing biological imbalances and promoting resistance and recurrence of high populations of pests and pathogens (upwelling). This has contributed to the appearance of new pests that were previously under natural control. To develop analytical methods that are able to quantify residues pesticide in complex environment. It is still a challenge for many laboratories. The integration of two analytical methods one ecotoxicological and another chemical demonstrates the potential for environmental analysis of methamidophos. The aim of this study was to evaluate an ecotoxicological method as "screening" analytical methamidophos in the soil and perform analytical confirmation in the samples of the concentration of the analyte by chemical method LC-MS/MS In this work we tested two soils: a clayey and sandy, both in contact with the kinetic methamidophos model followed pseudo-second order. The clay soil showed higher absorption of methamidophos and followed the Freundlich model, while the sandy, the Langmuir model. The chemical method was validated LC-MS/MS satisfactory, showing all parameters of linearity, range, precision, accuracy, and sensitivity adequate. In chronic ecotoxicological tests with C. dubia, the NOEC was 4.93 and 3.24 for ng L-1 of methamidophos to elutriate assays of sandy and clay soils, respectively. The method for ecotoxicological levels was more sensitive than LC-MS/MS detection of methamidophos, loamy and sandy soils. However, decreasing the concentration of the standard for analytical methamidophos and adjusting for the validation conditions chemical acquires a limit of quantification (LOQ) in ng L-1, consistent with the provisions of ecotoxicological test. The methods described should be used as an analytical tool for methamidophos in soil, and the ecotoxicological analysis can be used as a "screening" and LC-MS/MS as confirmatory analysis of the analyte molecule, confirming the objectives of this work

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The epidemiology of temporomandibular disorders varies widely in the literature. The aim of this study was to determine the prevalence of TMD in dental students of the Federal University of Rio Grande do Norte assessed by different indexes. The sample consisted of 101 individuals selected by a randomized process, whose general outline was systematic sampling. For evaluation of the signs and symptoms of TMD, an anamnestic index, Fonseca s protocol, and two clinical indexes, the RDC/TMD (Research Diagnostic Criteria for Temporomandibular Disorders), or standard index, and the Helkimo s Clinical Dysfunction Index were applied. Data were analyzed using the chi-square test and kappa, besides verifying the sensitivity and specificity (5% significance). The diagnosis of TMD by different indexes showed a variation in the prevalence between 72.3% (Helkimo s Clinical index), 64.4% (Fonseca s anamnestic index) and 35.6% (RDC/TMD). There was no statistical difference between the sexes for the RDC/TMD, although this difference was found for Fonseca s and Helkimo s indexes (p<0.05). The most frequent type of TMD were joint disorders (Groups II and III), and the subtypes disc displacement with reduction (17.8%) and arthralgia (15.8%). Most individuals showed a mild TMD (45.5%) for both indexes, Fonseca and Helkimo. When comparing the types of diagnoses, RDC/TMD with Fonseca and Helkimo, low agreement was found (k=0.17 and k= 0.35, respectively). A moderate correlation between the severity of TMD was obtained (kw= 0.53) for Fonseca s protocol and Helkimo s index. High sensitivity and low specificity were seen for both diagnoses compared to standard, resulting in excessive false positives. Within the limitations of the study, it was concluded that the prevalence of TMD can vary widely, depending on the index used for its diagnosis

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The calculation of tooth mass discrepancy, essential for good planning and a proper orthodontic finishing, when performed manually, besides being laborious, requires considerable time consumption. The aim of this study was to develop and test Bolton Freeware, a software for analysis of the tooth mass discrepancy of Bolton, aiming to minimize the consumption of time in a less onerous way. The digital analysis of the software was done by means of two-dimensional scanning of plaster study models and compared to manual evaluation (gold standard), using 75 pairs of stone plaster study models divided into two groups according to the magnitude of the Curve of Spee (group I from 0 to 2 mm, group II greater than 2 to 3mm). All the models had permanent dentition and were in perfect condition. The manual evaluation was performed with a digital caliper and a calculator, and the time required to perform the analysis for both methods was recorded and compared. In addition, the software was evaluated by orthodontists regarding its use, by means of questionnaires developed specifically for this purpose. Calibration was performed prior to manual analysis, and excellent levels of inter-rater agreement were achieved, with ICC > 0.75 and r > 0.9 for total and anterior proportion. It was observed in the evaluation of error of the digital method that some teeth showed a significant systematic error, being the highest measured at 0.08 mm. The analysis of total tooth mass discrepancy performed by Bolton Freeware, for those cases in which the curve of Spee is mild and moderate, differ from manual analysis, on average, 0.09 mm and 0.07 mm respectively, for each tooth evaluated, with r> 0, 8 for total and anterior proportion. According to the specificity and sensitivity test, Bolton Freeware has an improved ability to detect true negatives, i.e. the presence of discrepancy. The Bolton analysis digitally performed was faster, with an average difference of time consumed to perform the analysis of Bolton between the two methods of approximately 6 minutes. Most experts interviewed (93%) approved the usability of the software

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Accelerated aging test is an important procedure to be used, beyond other aim, for breeding programs to select cultivars with storage and development potential under high relative humidity and temperature. At accelerated aging test in soybean seeds, the temperature and time of exhibition they were not still totally established, factors that cause divergence among the researchers, mainly with relationship to the most appropriate periods. The aim was to evaluate the behavior of soybean seeds submitted to accelerated aging test. Seeds of the varieties IAC-15, CAC-1, FT-Estrela and IAC-Foscarin 31 were submitted to germination test, electrical conductivity and accelerated aging (41 degrees C, during 44, 48, 52, 56, 60, 64, 68, 72 and 76 hours). There are differences among cultivars evaluated in relation to accelerated aging test sensibilility; the cultivars are sensibles to increasing the exposition time; the accelerated aging test can be used to select cultivars in breeding programs; the cultivar FT-Estrela can be sowed at regions with high temperature and humidity.

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Comparação entre as duas versões da dedução kantiana dos conceitos puros do entendimento, a da 1ª edição de 1781 e a de 1787. Focam-se aqui principalmente as discrepâncias referentes à dedução objetiva, isto é, aquela encarregada de demonstrar que as categorias são as condições de possibilidade dos objetos de experiência

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

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RePART (Reward/Punishment ART) is a neural model that constitutes a variation of the Fuzzy Artmap model. This network was proposed in order to minimize the inherent problems in the Artmap-based model, such as the proliferation of categories and misclassification. RePART makes use of additional mechanisms, such as an instance counting parameter, a reward/punishment process and a variable vigilance parameter. The instance counting parameter, for instance, aims to minimize the misclassification problem, which is a consequence of the sensitivity to the noises, frequently presents in Artmap-based models. On the other hand, the use of the variable vigilance parameter tries to smoouth out the category proliferation problem, which is inherent of Artmap-based models, decreasing the complexity of the net. RePART was originally proposed in order to minimize the aforementioned problems and it was shown to have better performance (higer accuracy and lower complexity) than Artmap-based models. This work proposes an investigation of the performance of the RePART model in classifier ensembles. Different sizes, learning strategies and structures will be used in this investigation. As a result of this investigation, it is aimed to define the main advantages and drawbacks of this model, when used as a component in classifier ensembles. This can provide a broader foundation for the use of RePART in other pattern recognition applications

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JUSTIFICATIVA E OBJETIVOS: Ainda não está bem estabelecida a concentração de lidocaína que é potencialmente capaz de determinar lesão no tecido nervoso. O objetivo desta pesquisa foi estudar os efeitos sobre a medula espinhal e as meninges, de concentrações crescentes de lidocaína administrada por via subaracnóidea, em injeção única através de agulha de Quincke. MÉTODO: Após a aprovação da Comissão de Ética em Experimentação Animal, 40 cães adultos foram anestesiados com fentanil e etomidato e submetidos a punção subaracnóidea com agulha de Quincke 22G 21/2 para introdução de 1 mL, em 10 segundos, de solução glicosada a 7,5% - Grupo 1; lidocaína a 5% em solução glicosada a 7,5% - Grupo 2; lidocaína a 7,5% em solução glicosada a 7,5% - Grupo 3; lidocaína a 10% em solução glicosada a 7,5% - Grupo 4. Após a recuperação da anestesia venosa, foram observados, no período em que os animais estavam em vigência do bloqueio subaracnóideo, a presença de bloqueio motor, o tônus do esfíncter anal (normal ou relaxado) e o nível de bloqueio sensitivo nos diferentes dermátomos das regiões cervical, torácica, lombar e sacral. Os animais permaneceram em cativeiro por 72 horas. Foram avaliados o tônus do esfíncter anal, a motricidade das patas posteriores, a sensibilidade dolorosa nas patas anteriores e posteriores e nos dermátomos sacrais, lombares e torácicos. Após serem sacrificados por eletrocussão sob anestesia, foram retiradas porções lombar e sacral da medula espinhal e das meninges para exame histológico por microscopia óptica. RESULTADOS: Nenhum animal dos Grupos 1 e 2 apresentou lesões clínicas ou histológicas. Três animais do Grupo 3 apresentaram alterações motoras nas patas posteriores e relaxamento do esfíncter anal. Nestes, foram observados focos de necrose na região posterior (dois cães) e necrose em faixa em toda a superfície medular (um cão). em um outro animal deste grupo, no qual foram notados focos de necrose, em área inferior a 5% do campo histológico não foram encontradas alterações clínicas. Sete animais do Grupo 4 apresentaram alterações clínicas (paralisia ou diminuição de força muscular nas patas posteriores, relaxamento do esfíncter anal) e histológicas (necrose na faixa da superfície medular ou focos de necrose de tecido nervoso). CONCLUSÕES: Neste estudo, a lidocaína em concentrações superiores a 7,5%, em injeção única, administrada no espaço subaracnóideo por meio de agulha de Quincke, determinou alterações histológicas sobre a medula espinhal, mas não sobre as meninges.

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OBJETIVO: Determinar a acurácia das variáveis: tempo de escada (tTE), potência de escada (PTE), teste de caminhada (TC6) e volume expiratório forçado (VEF1) utilizando o consumo máximo de oxigênio (VO2máx) como padrão-ouro. MÉTODOS: Os testes foram realizados em 51 pacientes. O VEF1 foi obtido através da espirometria. O TC6 foi realizado em corredor plano de 120m. O TE foi realizado em escada de 6 lances obtendo-se tTE e PTE. O VO2máx foi obtido por ergoespirometria, utilizando o protocolo de Balke. Foram calculados a correlação linear de Pearson (r) e os valores de p, entre VO2máx e variáveis. Para o cálculo da acurácia, foram obtidos os pontos de corte, através da curva característica operacional (ROC). A estatística Kappa (k) foi utilizada para cálculo da concordância. RESULTADOS: Obteve-se as acurácias: tTE - 86%, TC6 - 80%, PTE - 71%, VEF1(L) - 67%, VEF1% - 63%. Para o tTE e TC6 combinados em paralelo, obteve-se sensibilidade de 93,5% e em série, especificidade de 96,4%. CONCLUSÃO: O tTE foi a variável que apresentou a melhor acurácia. Quando combinados o tTE e TC6 podem ter especificidade e sensibilidade próxima de 100%. Estes testes deveriam ser mais usados rotineiramente, especialmente quando a ergoespirometria para a medida de VO2máx não é disponível.

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Edaphic ecosystems are the basis for the production of terrestrial biological resources and their dynamics affect not only the natural environment but also society and their economic activities. In Caatinga biome, the semi-arid climate associated with an inadequate soil management has increased the degradation and loss of productive potential of the soil. In this context, the study of soil fauna, including springtails, becomes an important indicator of soil quality. This study aimed to evaluate the fauna of Collembola in an area of Caatinga of Rio Grande do Norte State and the influence of biotic and abiotic factors, such as soil, vegetation and climate characteristics, on the structure of the taxocenosis. The environmental variables which were used were the following ones: granulometry (represented by the proportion of sand), quantity of organic matter and soil pH, richness, density and aerial biomass of the vegetal structure, and necromass. We used pitfall traps intending to collect specimens of the epiedaphic fauna of Collembola in 30 points located on Cauaçu Farm, João Câmara, RN, in July (rainy season) and November (dry season) 2011. We collected 5513 individuals of 15 species distributed in 13 genera and 9 families of Collembola. Five of the recorded species are new to science, confirming the expected high degree of endemism for Caatinga biome, and the highest abundance was recorded in the rainy season, which suggests Collembola sensitivity to low humidity. Four species were more abundant in the dry season, all of them belonged to the Order Entomobryomorpha. Results of statistical analyzes suggest that plant species richness, aerial biomass of vegetal structure, proportion of sand in the soil, pH and humidity are the main influences to the abundance of Collembola in the region studied

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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O diagnóstico da trombose venosa profunda sintomática está bem estabelecido com o uso do mapeamento dúplex, que apresenta sensibilidade de 100% e especificidade de 98%, para trombose venosa profunda proximal, e sensibilidade de 94% e especificidade de 75%, para distal. Na trombose venosa profunda recente e assintomática, o diagnóstico com o mapeamento dúplex ainda não está bem estabelecido, mostrando uma queda na acurácia desse método diagnóstico. Essa queda é devida ao fato de o trombo recente não ser oclusivo, apresentar a mesma ecogenicidade do sangue e uma consistência diminuída, prejudicando o teste da compressibilidade, que é o mais sensível para diagnóstico da trombose venosa profunda. Nesta revisão, serão revistos artigos publicados que avaliaram a acurácia do mapeamento dúplex no diagnóstico da trombose venosa profunda assintomática.

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Foram caracterizados os sorotipos, o perfil de sensibilidade microbiana e os achados clínico-epidemiológicos em 53 linhagens do gênero Salmonella isoladas de 41 cães, nove equinos e três bovinos, acometidos por diferentes manifestações clínicas entre 1997 e 2007. Salmonella Typhimurium (45,3%), Salmonella enterica (22,6%), Salmonella Enteritidis (7,5%), Salmonella enterica subsp enterica 4,5,12i (5,7%), Salmonella Newport (5,7%), Salmonella Dublin (3,8%), Salmonella Agona (3,8%), Salmonella Glostrup (3,8%), Salmonella Saintpaul (1,8%) foram os sorotipos encontrados. Ciprofloxacina (100,0%), norfloxacina (100,0%) e gentamicina (100,0%) foram os antimicrobianos mais efetivos, enquanto a maior resistência das linhagens foi observada para ceftiofur (28,5%) e florfenicol (7,0%). As linhagens foram isoladas de animais com enterite, infecção do trato urinário, septicemia, piometra, pneumonia e conjuntivite. Ressalta-se para o predomínio do sorovar Typhimurium nas diferentes manifestações da salmonelose nos animais. Destaca-se, também, a identificação de sorotipos nos animais que também são observados em casos de salmonelose em humanos

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