980 resultados para MODIFIED HODGE TEST


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Glass fibre-reinforced plastics (GFRP), nowadays commonly used in the construction, transportation and automobile sectors, have been considered inherently difficult to recycle due to both: cross-linked nature of thermoset resins, which cannot be remolded, and complex composition of the composite itself, which includes glass fibres, matrix and different types of inorganic fillers. Presently, most of the GFRP waste is landfilled leading to negative environmental impacts and supplementary added costs. With an increasing awareness of environmental matters and the subsequent desire to save resources, recycling would convert an expensive waste disposal into a profitable reusable material. There are several methods to recycle GFR thermostable materials: (a) incineration, with partial energy recovery due to the heat generated during organic part combustion; (b) thermal and/or chemical recycling, such as solvolysis, pyrolisis and similar thermal decomposition processes, with glass fibre recovering; and (c) mechanical recycling or size reduction, in which the material is subjected to a milling process in order to obtain a specific grain size that makes the material suitable as reinforcement in new formulations. This last method has important advantages over the previous ones: there is no atmospheric pollution by gas emission, a much simpler equipment is required as compared with ovens necessary for thermal recycling processes, and does not require the use of chemical solvents with subsequent environmental impacts. In this study the effect of incorporation of recycled GFRP waste materials, obtained by means of milling processes, on mechanical behavior of polyester polymer mortars was assessed. For this purpose, different contents of recycled GFRP waste materials, with distinct size gradings, were incorporated into polyester polymer mortars as sand aggregates and filler replacements. The effect of GFRP waste treatment with silane coupling agent was also assessed. Design of experiments and data treatment were accomplish by means of factorial design and analysis of variance ANOVA. The use of factorial experiment design, instead of the one factor at-a-time method is efficient at allowing the evaluation of the effects and possible interactions of the different material factors involved. Experimental results were promising toward the recyclability of GFRP waste materials as polymer mortar aggregates, without significant loss of mechanical properties with regard to non-modified polymer mortars.

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Performance indexes of the peroxidase antibody test were compared to that of the fluorescent antibody test. The peroxidase antibody test had a statistically higher sensitivity and negative predictive value and a higher efficiency than the fluorescent antibody test but its specificity and positive predictive value were within the 95% confidence limits for the values found for the fluorescent antibody test. Such differences did not change when Chagas' disease and visceral leishmaniasis sera were included in index calculations. Statistical analysis showed that the two tests have a substantial degree of agreement but the immunofluorescent test had a specificity index and a positive predictive value equal to 100.0% when Chagas' disease and visceral leishmaniasis sera were not included in the calculations of the performance index; in this instance, a positive test result equals a disclosure of the disease attribute due to the inexistence of false positive results. The enzyme/ protein ratio of the peroxidase conjugate, resulting in heavy or light-labeled conjugates may pose technical problems to its use in serology tests.

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We used the micro- and macroimmunodiffusion test for the qualitative and quantitative measurement of anti - P. brasiliensis antibodies in serum of patients with paracoccidioidomycosis. All 103 paracoccidioidomycosis sera (100%) were positive in the micro test versus 87% positivity index in the macrotest. All 83 control sera from patients with other diseases were negative in both tests. Titers of the positive sera tended to be higher in the microtest, which revealed sharper and easier to read precipiting bands. Microimmunodiffusion is simple to be performed, requires a minimum amount of reagents and allows the simultaneous testing of 102 sera. It may replace the macrotest specially in laboratories dealing with great serologic routine.

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In the present work the immune adherence hemagglutination test (IAHA) was standardized in a simplified procedure. This test showed good reproducibility, better than the classical mice serum neutralization test (SN). The tests showed high correlation degree: high titers in one test corresponded to high titers in the other one, and the same occured with low titers. The IAHA test is extremely simple, fast to perform, and of low cost when compared to tests such as SN or indirect immunofluorescense (IIF). It also proved to be useful in less sophisticated laboratories or even as a screening test for the titration of rabies antibodies.

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In this work, the effect of incorporation of recycled glass fibre reinforced plastics (GFRP) waste materials, obtained by means of shredding and milling processes, on mechanical behavior of polyester polymer mortar (PM) materials was assessed. For this purpose, different contents of GFRP recyclates (between 4% up to 12% in mass), were incorporated into polyester PM materials as sand aggregates and filler replacements. The effect of silane coupling agent addition to resin binder was also evaluated. Applied waste material was proceeding from the shredding of the leftovers resultant from the cutting and assembly processes of GFRP pultrusion profiles. Currently, these leftovers, jointly with unfinished products and scrap resulting from pultrusion manufacturing process, are landfilled, with supplementary added costs. Thus, besides the evident environmental benefits, a viable and feasible solution for these wastes would also conduct to significant economic advantages. Design of experiments and data treatment were accomplish by means of full factorial design approach and analysis of variance ANOVA. Experimental results were promising toward the recyclability of GFRP waste materials as aggregates and reinforcement for PM materials, with significant improvements on mechanical properties with regard to non-modified formulations.

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To date, glass fibre reinforced polymer (GFRP) waste recycling is very limited and restricted by thermoset nature of binder matrix and lack of economically viable enduse applications for the recyclates. In this study, efforts were made in order to recycle grinded GFRP waste proceeding from pultrusion production scrap, into new and sustainable composite materials. For this purpose, GFRP waste recyclates, a mix of powdered and fibrous materials, were incorporated into polyester based mortars as fine aggregate and filler replacements, at different load contents (between 4% up to 12% of total mass) and particle size distributions. Potential recycling solution was assessed by mechanical behaviour of resultant GFRP waste modified polymer mortars. Test results revealed that GFRP waste filled polymer mortars present improved flexural and compressive behaviour over unmodified polyester based mortars, thus indicating the feasibility of GFRP waste reuse in concrete-polymer composites.

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Indirect Immunofluorescence (IFA), Plaque Reduction Neutralization (PRN) and Haemagglutination Inhibition (HI) tests for measles antibodies were carried out in 197 sera obtained from umbilical cord and vaccinated children. The IFA was also applied to blood samples collected with filter paper. IFA results demonstrated that the test is relatively simple to perform, with good reproducibility for different antigen lots. Good correlation was obtained between IFA, PRN and HI antibody titers. Better correlation was demonstrated with IFA and PRN than with HI and PRN tests. Sensitivity of IFA in detecting antibody was less effective than PRN, however more effective than HI using rhesus monkey red blood cells. PRN antibody titers over 100 were detected by IFA but not by HI (9.7% with negative results). IFA may be of considerable practical use and able to substitute HI in Seroepidemiological surveys and to evaluate vaccine efficacy. It also can be simplified by employing filter paper collected samples.

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Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Engenharia Informática

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Le test ELISA-TÉTANOS (Biosys, France) a été utilisé pour le titrage des anti-corps tétaniques (sensibilité = 0,0025 UI/ml) en sérums humains de donneurs de sang, 566 hommes et 108 femmes, âges de 18 à 58 ans, moyenne de 29 ans, provenant de São Paulo, SP, Brésil. L'OMS, acceptant seulement la séroneutralisation sur souris (NT), la méthode de référence, pour les études sur la protection contre le tétanos, préconise le titre de 0,01 UI/ml comme minimum protecteur. BOURLEAUD & HUET ont proposé la limite de 0,06 UI/ml quand s'emploie le test ELISA, en attendant à une certaine discordance inévitable entre les méthodes. Parmi les 674 sérums étudiés, 178 (26,41%) n'ont pas présenté d'anticorps (< 0,0025 UI/ml); 413 (61,28%) ont présenté des résultats égaux ou supérieurs à 0,01 UI/ml et en 232 (34,42%) les titres ont été égaux ou supérieurs à 0,06 UI/ml. Le pourcentage d'individus protégés a été inversement proportionnel à 1'âge: environ 50% dans le groupe le plus jeune (hommes de 18 à 35 ans et femmes de 18 à 23 ans) contre environ 10% dans le groupe de plus de 42 ans ont présenté des titres sûrement protecteurs (> 0,06 UI/ml).

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Helicobacter pylori was investigated in 189 patients for culture, microscopic visualization of campylobacter-like organisms (CLO) and a ten minute urease test. In 136 (72%) the bacteria was isolated, and in 98 of them CLO were histologically detected. Specificity, sensitivity, positive and negative predictive values of microscopic visualization of CLO were: 0.77, 0.73, 0.97 and 0.51, respectively; 98 culture-positive patients were urease test positive. Specificity, sensitivity, positive and negative predictive values of the urease test were: 0.83, 0.72, 0.92 and 0.54, respectively. Comparing the urease test with culture of H. pylori combined with microscopic visualization of CLO, its specificity, sensitivity, positive and negative predictive values were: 0.95, 0.71, 0.98 and 0.48, respectively. Probably, these values are not real, since bacteria different from H. pylori could be misclassified as CLO.

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The performance of an antigen of L. major-like promastigotes for the serological diagnosis of mucocutaneous leishmaniasis in the IgG-immunofluorescent test was compared to that of an antigen of L. braziliensis braziliensis. Each antigen was used to test two hundred and twenty-four sera of etiologies such as mucocutaneous leishmaniasis, deep mycoses, toxoplasmosis, malaria, Chagas' disease, visceral leishmaniasis, anti-nuclear factor, schistosomaiasis, rheumatoid factor and normal controls. Agreement between responses to each antigen was high: 77.2% of leishmaniases sera agreed on a positive or a negative result to both antigens and 91.1 % of control sera. Cross reactivity was restricted to Chagas' disease sera, visceral leishmaniasis, anti-nuclear factor and paracoccidiodomycosis. The quantitative response of leishmaniasis and Chagas' disease sera to both antigens was evaluated by a linear regression; although the y-intercept and the slope were different for each antigen, neither was better than the other in the disclosure of anti-Leishmania antibodies. In the case of Chagas' disease sera the L. major-like antigen was better than L. b. braziliensis' to disclose cross-reacting antibodies.

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The elastic behavior of the demand consumption jointly used with other available resources such as distributed generation (DG) can play a crucial role for the success of smart grids. The intensive use of Distributed Energy Resources (DER) and the technical and contractual constraints result in large-scale non linear optimization problems that require computational intelligence methods to be solved. This paper proposes a Particle Swarm Optimization (PSO) based methodology to support the minimization of the operation costs of a virtual power player that manages the resources in a distribution network and the network itself. Resources include the DER available in the considered time period and the energy that can be bought from external energy suppliers. Network constraints are considered. The proposed approach uses Gaussian mutation of the strategic parameters and contextual self-parameterization of the maximum and minimum particle velocities. The case study considers a real 937 bus distribution network, with 20310 consumers and 548 distributed generators. The obtained solutions are compared with a deterministic approach and with PSO without mutation and Evolutionary PSO, both using self-parameterization.

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A novel sensitive electrochemical sensor was developed by electropolymerization of pyrrole(PY)and molecularly imprinted polymer (MIP)which was synthesized onto a glassy carbon electrode (GCE) in aqueous solution using cyclic voltammetry in the presence of Trimethoprim (TMP) as template molecules. Furthermore,a previous electrode modification was performed by deposition of a suspension of graphene on the electrode's surface. The performance of the imprinted and non-imprinted (NIP) films was evaluated by impedance spectroscopy (EIS) and cyclic voltammetry (CV) of a ferric solution. The molecularly imprinted film exhibited a high selectivity and sensitivity toward TMP. The sensor presented a linear range, between peak current intensity and logarithm of TMP concentration between 1.0x10-6 and 1.0x10-4 M. The results were accurate (with recoveries higher than 94%), precise (with standard deviations less than 5%) and the detection limit was 1.3x10-7 M. The new sensor is selective, simple to construct and easy to operate. The MIP sensor was successfully applied to quantify TMP in urinesamples.

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Dissertação de Natureza Científica elaborada no Laboratório Nacional de Engenharia Civil (LNEC) para obtenção do grau de mestre em Engenharia Civil na Área de Especialização de Hidráulica no âmbito do protocolo de cooperação entre o ISEL e o LNEC

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Se evaluó la utilidad de la prueba de aglutinación directa (AD) para diagnosticar el Mal de Caderas. Se emplearon cuarenta y cuatro sueros provenientes de dos lotes de equinos naturalmente infectados con el Trypanosoma evansi (Lote 1 y Lote 2). La AD fue positiva (Aglutinación > 1:512) en 13 de 16 equinos (81.2%), de los que se aislaron los parásitos. En doce de estos animales (92%) se detectaron IgM anti T. evansi mediante la AD realizada con 2-mercaptoetanol (AD + 2-ME). La AD fue positiva en 17 de los 28 equinos que resultaron negativos al diagnóstico parasitológico. Un tercer lote de cinco equinos infectados con T. evansi que presentaba elevados títulos de AD, fue tratado con Suramina Sódica (Nagano1-Bayer). La AD + 2-ME evidenció en cuatro animales que, gran parte de estos anticuerpos se ubicaban en la fracción IgM. Posterior al tratamiento farmacológico y, en concordancia de la negativización de la parasitemia, la detección de la IgM anti T. evansi no fue posible, mientras que los anticuerpos IgG continuaron detectándose a los doce meses post-tratamiento en valores de 1:512, en tres animales. Cincuenta sueros de equinos de una zona libre del parásito, que se emplearon como controles, fueron negativos a la AD. Se recomienda la utilización de la AD y AD + 2-ME para el uso de rutina en el diagnóstico del Mal de Caderas de los equinos, en combinación con otros métodos parasitológicos sensibles.