92 resultados para efficiency measurement
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)
Resumo:
Background: Shrimp is a frequent cause of food allergy. Tropomyosin is the major allergen in shrimp, and it shares homology to tropomyosins from other crustaceans, dust mites, cockroach, and parasites. Objective: The aim of this study was to determine the value of detection of IgE to shrimp tropomyosin in the diagnosis of shrimp allergy. Methods: We have studied 35 patients with asthma, rhinitis, or both who were sensitized to Dermatophagoides pteronyssinus. All subjects underwent skin prick testing in addition to double-blind, placebo-controlled food challenges (DBPCFC); oral open challenges; or both with shrimp. Measurements of IgE to shrimp and shrimp tropomyosin were carried out by means of CAP and chimeric ELISA, respectively. Results: Oral challenges confirmed the diagnosis of shrimp allergy in 7 patients. IgE measurement to shrimp tropomyosin was positive in 71.4% of the patients with shrimp allergy. Of the 28 patients without shrimp allergy, only 7.1% (2/28) had IgE to shrimp tropomyosin compared with 25% (7/28) who had IgE to shrimp and 35.7% (10/28) who had positive skin prick test responses to shrimp. Sensitivity was similar for all 3 methods (71.4%); in contrast, specificity of IgE to shrimp tropomyosin (92.8%) was greater than that of IgE to shrimp (75%) and skin prick testing (64.2%). With regard to diagnostic efficiency, measurement of IgE to shrimp tropomyosin was superior to measurement of IgE to shrimp and skin prick testing (88.5%, 74.2%, and 65.7%, respectively). Conclusion: Use of measurements of IgE to shrimp tropomyosin provided added value to the diagnosis of shrimp allergy. (J Allergy Clin Immunol 2010;125:872-8.)
Resumo:
Objective. To determine the blood recirculation ratio in the vascular access of patients on hemodialysis, and to calculate the Kt/Vs obtained with the different techniques of arteriovenous fistula punctures. Materials and Methods. A total of 174 patients were divided according to the technique used for arteriovenous fistula puncture: group 1, needles in opposite directions and with a distance of 5 cm or more between them; group 2, needles in opposite directions but with a distance of less than 5 cm; group 3, unidirectional needles with both directed to the heart and with a distance of 5 cm or more; group 4, unidirectional needles but separated by a distance of less than 5 cm between needles; and group 5, patients carrying a temporary venous catheter. Blood samples were collected for urea analysis, pre and post-dialysis for Kt/V rate, and other samples for calculation of the access recirculation. Results. Group 1 presented the lowest rate of access recirculation (8.51 +/- 4.90%) and the best Kt/V (1.71 +/- 0.36), while group 4 presented the worst access recirculation (20.68 +/- 4.92%) and Kt/V (1.16 +/- 0.26). All groups differed significantly from group 4 (p < 0.05), except group 5 with regard for Kt/V parameter. Discussion. The technique of arteriovenous fistula puncture is an essential factor to decrease the access recirculation and assure better results of measurement of hemodialysis adequacy. On the basis of the results obtained, insertion of the needles in the same direction and with a distance of less than 5 cm between them should be avoided.
Resumo:
We have investigated a possible correlation between the photostability and photodynamic efficacy for different photosensitizers; hematoporphyrin derivatives and chlorines. To perform such analysis, we combined the depth of necrosis (d (nec)) measurement, expressed by the light threshold dose and a photodegradation parameter, measured from investigation of photosensitizer degradation in solution. The d (nec) analysis allows us to determine the light threshold dose and compare its value with the existent results in the literature. The use of simple models to understand basic features of Photodynamic Therapy (PDT) may contribute to the solid establishment of dosimetry in PDT, enhancing its use in the clinical management of cancers and others lesions. Using hematoporphyrin derivatives and chlorines photosensitizers we investigated their properties related to the photodegradation in solution and the light threshold dose (D (th)) in rat livers.
Resumo:
Specific choices about how to represent complex networks can have a substantial impact on the execution time required for the respective construction and analysis of those structures. In this work we report a comparison of the effects of representing complex networks statically by adjacency matrices or dynamically by adjacency lists. Three theoretical models of complex networks are considered: two types of Erdos-Renyi as well as the Barabasi-Albert model. We investigated the effect of the different representations with respect to the construction and measurement of several topological properties (i.e. degree, clustering coefficient, shortest path length, and betweenness centrality). We found that different forms of representation generally have a substantial effect on the execution time, with the sparse representation frequently resulting in remarkably superior performance. (C) 2011 Elsevier B.V. All rights reserved.
Resumo:
Neste trabalho foi avaliado o desempenho produtivo de nove animais jovens Zebu × Holandês em comparação a nove animais da raça Holandesa para produção de vitelos. Todos os animais foram mantidos em condições idênticas de ambiente, manejo e alimentação, com acompanhamento individual da ingestão de matéria seca. As medidas de avaliação do desenvolvimento animal, conversão e eficiência alimentar possibilitaram comparações entre os tratamentos, a partir de delineamento inteiramente casualizado. Os bezerros Zebu × Holandês apresentaram maior ganho de perímetro torácico (23,3 cm) e ganho de peso diário (1,45 kg), além de conversão alimentar (2,77 kg de MS/kg de peso corporal), se comparados aos bezerros da raça Holandesa, com, respectivamente, 18,5 cm de perímetro torácico, 1,16 kg de ganho de peso diário e conversão alimentar de 3,48 kg de MS/kg de peso corporal. Não houve diferença na ingestão de matéria seca entre os animais avaliados. Quanto ao estudo econômico da produção de carne de vitelo, os animais mestiços apresentaram o menor custo de produção por quilo de carne produzida e, conseqüentemente, o melhor potencial de produção de vitelos a partir de animais Zebu × Holandês, como atividade complementar à produção de leite.
Resumo:
Two experiments evaluated an operant procedure for establishing stimulus control using auditory and electrical stimuli as a baseline for measuring the electrical current threshold of electrodes implanted in the cochlea. Twenty-one prelingually deaf children, users of cochlear implants, learned a Go/No Go auditory discrimination task (i.e., pressing a button in the presence of the stimulus but not in its absence). When the simple discrimination baseline became stable, the electrical current was manipulated in descending and ascending series according to an adapted staircase method. Thresholds were determined for three electrodes, one in each location in the cochlea (basal, medial, and apical). Stimulus control was maintained within a certain range of decreasing electrical current but was eventually disrupted. Increasing the current recovered stimulus control, thus allowing the determination of a range of electrical currents that could be defined as the threshold. The present study demonstrated the feasibility of the operant procedure combined with a psychophysical method for threshold assessment, thus contributing to the routine fitting and maintenance of cochlear implants within the limitations of a hospital setting.
Resumo:
A study was performed in order to determine the efficiency of the simultaneous use of the photoinitiators phenylpropanedione (PPD) and camphorquinone (CQ) in the polymerization of acrylic polymers and evaluate possible mechanisms leading to synergism or antagonism. It was found that efficiencies of both initiators taken individually are higher than that of their mixture, indicating that when both dyes are used simultaneously there will be an energy transfer from the more efficient initiator (CQ) to the less efficient one (PPD). Also, there was no proof of any reaction between the amine present in the CQ formulation and the PPD excited state.
Resumo:
The flavonoids present in sugarcane (Saccharum officinarum) extracts were analyzed by liquid chromatography - mass spectrometry (LC-MS), and a study of the fragmentation patterns of selected flavonoids was conducted using orthogonal acceleration time-of-flight electrospray ionization mass spectrometry (ESI-oa-ToF MS). Seven C- and O-glycosylflavones were identified in the extracts, namely, schaftoside, isoschaftoside, luteolin-8-C-(rhamnosylglucoside), vitexin, orientin, tricin-7-O-neohesperidoside and tricin-7-O-glucoside. Of these, five were identified in the absence of direct comparison with their respective standards. The described method also permitted the differentiation of the 6-C and 8-C isomeric flavones, schaftoside and isoschaftoside. The combination of fragmentation data and exact mass measurement showed to be complimentary to the HPLC-UV-MS techniques previously utilized for isomers discrimination in sugarcane studies.
Resumo:
Searches for field horizontal-branch (FHB) stars in the halo of the Galaxy in the past have been carried out by several techniques, such as objective-prism surveys and visual or infrared photometric surveys. By choosing adequate color criteria, it is possible to improve the efficiency of identifying bona fide FHB stars among the other objects that exhibit similar characteristics, such as main-sequence A-stars, blue stragglers, subdwarfs, etc. In this work, we report the results of a spectroscopic survey carried out near the south Galactic pole intended to validate FHB stars originally selected from the HK objective-prism survey of Beers and colleagues, based on near-infrared color indices. A comparison between the stellar spectra obtained in this survey with theoretical stellar atmosphere models allows us to determine T(eff), log g, and [Fe/H] for 13 stars in the sample. Stellar temperatures were calculated from measured (B-V)(o), when this measurement was available (16 stars). The color index criteria adopted in this work are shown to correctly classify 30% of the sample as FHB, 25% as non-FHB (main-sequence stars and subdwarfes), whereas 40% could not be distinguished between FHB and main-sequence stars. We compare the efficacy of different color criteria in the literature intended to select FHB stars, and discuss the use of the Mg II 4481 line to estimate the metallicity.
Resumo:
Using differential x-ray absorption spectroscopy (DiffXAS) we have measured and quantified the intrinsic, atomic-scale magnetostriction of Fe(81)Ga(19). By exploiting the chemical selectivity of DiffXAS, the Fe and Ga local environments have been assessed individually. The enhanced magnetostriction induced by the addition of Ga to Fe was found to originate from the Ga environment, where lambda(gamma,2)(approximate to (3/2)lambda(100)) is 390 +/- 40 ppm. In this environment, < 001 > Ga-Ga pair defects were found to exist, which mediate the magnetostriction by inducing large strains in the surrounding Ga-Fe bonds. For the first time, intrinsic, chemically selective magnetostrictive strain has been measured and quantified at the atomic level, allowing true comparison with theory.
Resumo:
Introduction. This protocol aims at measuring fruit ethylene production during ripening. It can be used to compare ethylene production between different banana varieties or to compare ethylene production between fruit produced in different pedo-climatic conditions. The principle, key advantages, starting plant material, time required and expected results are presented. Materials and methods. This part describes the required laboratory materials and the three steps necessary for calculating the amount of ethylene produced during banana postharvest ripening. Possible troubleshooting is considered.
Resumo:
Introduction. We present some protocols aiming at partially characterizing banana fruit quality through measurement of some key biochemical parameters. The principle, key advantages, starting plant material, time required and expected results are presented. Materials and methods. This part describes the required laboratory materials and the steps necessary for achieving four protocols making it possible to measure sugar, organic acids and free ACC contents, and in vitro ACC oxidase activity. Results. Standard results obtained by using the protocols described are presented in the figures.
Resumo:
Introduction. This protocol aims at measuring the storage life potential of banana fruit, and at determining the physiological age of fruit. The principle, key advantages, starting plant material, time required and expected results are presented. Materials and methods. This part describes the required laboratory materials and the five steps necessary for calculating the banana green life duration, which corresponds to the number of days between the fruit harvest and climacteric crisis. Results. The measurement of O-2 and CO2 concentrations allows one to detect the climacteric peak which marks the end of the banana green life.
Resumo:
Introduction. This protocol aims at evaluating (a) the efficacy of new fungicides for the control of post-harvest diseases, (b) the efficacy of various application methods for the chemical control of post-harvest diseases, and (c) the quality of the fungicide solution during the same packing day where this solution is recycled. The principle, key advantages, starting plant material, time required and expected results are presented. Materials and methods. Materials required and details of the eighteen steps of the protocol (fruit sampling and inoculum preparation, wound anthracnose study, quiescent anthracnose study, and crown-rot study) are described. Results. Comparison between untreated control bananas and bananas treated with fungicide allows the calculation of the fungicide treatment efficacy.
Resumo:
The increasing participation of the society in the decision-making process related to public politics stimulates public administration in Brazil to search for mechanisms to demonstrate efficiency and disclosure in resource application. The main objective of this work is to calculate the economic value added to the society by Public University Hospitals. Therefore, a Public University Hospital case study has been carried out and its economic performance evaluated during a period of three years. This study has shown that the economic value added to the society in the long term by the entity is positive. The proposed value measurement has indicated that the society is getting a superior return from the opportunity costs of capital invested, that is, the hospital is constructing economic value and consequently contributing to the social welfare.