976 resultados para Combination methods


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Infrared polarization and intensity imagery provide complementary and discriminative information in image understanding and interpretation. In this paper, a novel fusion method is proposed by effectively merging the information with various combination rules. It makes use of both low-frequency and highfrequency images components from support value transform (SVT), and applies fuzzy logic in the combination process. Images (both infrared polarization and intensity images) to be fused are firstly decomposed into low-frequency component images and support value image sequences by the SVT. Then the low-frequency component images are combined using a fuzzy combination rule blending three sub-combination methods of (1) region feature maximum, (2) region feature weighting average, and (3) pixel value maximum; and the support value image sequences are merged using a fuzzy combination rule fusing two sub-combination methods of (1) pixel energy maximum and (2) region feature weighting. With the variables of two newly defined features, i.e. the low-frequency difference feature for low-frequency component images and the support-value difference feature for support value image sequences, trapezoidal membership functions are proposed and developed in tuning the fuzzy fusion process. Finally the fused image is obtained by inverse SVT operations. Experimental results of visual inspection and quantitative evaluation both indicate the superiority of the proposed method to its counterparts in image fusion of infrared polarization and intensity images.

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Purpose: The aim of this study was to evaluate the effect of three denture hygiene methods against different microbial biofilms formed on acrylic resin specimens. Materials and methods: The set (sterile stainless steel basket and specimens) was contaminated (37 degrees C for 48 hours) by a microbial inoculum with 106 colony-forming units (CFU)/ml (standard strains: Staphylococcus aureus, Streptococcus mutans, Escherichia coli, Candida albicans, Pseudomonas aeruginosa, and Enterococcus faecalis; field strains: S. mutans, C. albicans, C. glabrata, and C. tropicalis). After inoculation, specimens were cleansed by the following methods: (1) chemical: immersion in an alkaline peroxide solution (Bonyplus tablets) for 5 minutes; (2) mechanical: brushing with a dentifrice for removable prostheses (Dentu Creme) for 20 seconds; and (3) a combination of chemical and mechanical methods. Specimens were applied onto a Petri plate with appropriate culture medium for 10 minutes. Afterward, the specimens were removed and the plates incubated at 37 degrees C for 48 hours. Results: Chemical, mechanical, and combination methods showed no significant difference in the reduction of CFU for S. aureus, S. mutans (ATCC and field strain), and P. aeruginosa. Mechanical and combination methods were similar and more effective than the chemical method for E. faecalis, C. albicans (ATCC and field strain), and C. glabrata. The combination method was better than the chemical method for E. coli and C. tropicalis, and the mechanical method showed intermediate results. Conclusion: The three denture hygiene methods showed different effects depending on the type of microbial biofilms formed on acrylic base resin specimens.

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To avoid counter-intuitive result of classical Dempster's combination rule when dealing with highly conflict information, many improved combination methods have been developed through modifying the basic probability assignments (BPAs) of bodies of evidence (BOEs) by using a certain measure of the degree of conflict or uncertain information, such as Jousselme's distance, the pignistic probability distance and the ambiguity measure. However, if BOEs contain some non-singleton elements and the differences among their BPAs are larger than 0.5, the current conflict measure methods have limitations in describing the interrelationship among the conflict BOEs and may even lead to wrong combination results. In order to solve this problem, a new distance function, which is called supporting probability distance, is proposed to characterize the differences among BOEs. With the new distance, the information of how much a focal element is supported by the other focal elements in BOEs can be given. Also, a new combination rule based on the supporting probability distance is proposed for the combination of the conflicting evidences. The credibility and the discounting factor of each BOE are generated by the supporting probability distance and the weighted BOEs are combined directly using Dempster's rules. Analytical results of numerical examples show that the new distance has a better capability of describing the interrelationships among BOEs, especially for the highly conflicting BOEs containing non-singleton elements and the proposed new combination method has better applicability and effectiveness compared with the existing methods.

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Background: Remodeling of the extracellular matrix is one of the most striking features observed in the uterus during the estrous cycle and after hormone replacement. Versican (VER) is a hyaluronan-binding proteoglycan that undergoes RNA alternative splicing, generating four distinct isoforms. This study analyzed the synthesis and distribution of VER in mouse uterine tissues during the estrous cycle, in ovariectomized (OVX) animals and after 17beta-estradiol (E2) and medroxyprogesterone (MPA) treatments, either alone or in combination. Methods: Uteri from mice in all phases of the estrous cycle, and animals subjected to ovariectomy and hormone replacement were collected for immunoperoxidase staining for versican, as well as PCR and quantitative Real Time PCR. Results: In diestrus and proestrus, VER was exclusively expressed in the endometrial stroma. In estrus and metaestrus, VER was present in both endometrial stroma and myometrium. In OVX mice, VER immunoreaction was abolished in all uterine tissues. VER expression was restored by E2, MPA and E2+MPA treatments. Real Time PCR analysis showed that VER expression increases considerably in the MPA-treated group. Analysis of mRNA identified isoforms V0, V1 and V3 in the mouse uterus. Conclusion: These results show that the expression of versican in uterine tissues is modulated by ovarian steroid hormones, in a tissue-specific manner. VER is induced in the myometrium exclusively by E2, whereas MPA induces VER deposition only in the endometrial stroma.

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RESUMO - O estabelecimento de prioridades determina a sustentabilidade de qualquer sistema de saúde, pelo que urge identificar os procedimentos, metodologias e critérios de priorização. Não existem critérios nem métodos universais de os combinar, sendo que a sua seleção depende do contexto de aplicação. O presente projeto de estudo exploratório-descritivo tem por finalidade a criação de uma proposta de metodologia a adotar na determinação de prioridades do Plano Regional de Saúde de Lisboa e Vale do Tejo 2011-2016, contextualizada à região, tempo e circunstâncias. O estudo está organizado em duas etapas metodológicas: uma revisão bibliográfica, dirigida à identificação do método e dos critérios de determinação de prioridades, e a realização de um painel de Delphi, para validação do método de determinação de prioridades proposto, definição dos critérios e suas ponderações. Tendo sido encontrada evidência na literatura sobre as vantagens da utilização da Análise Multicritério da Tomada de Decisão, através da utilização do Método Aditivo Linear, na determinação de prioridades em saúde, foi selecionada esta metodologia, que obteve a concordância de 85% dos participantes para a sua utilização no contexto em estudo, na primeira ronda do painel de Delphi. Os resultados preliminares do estudo, obtidos na primeira ronda, mostram que um dos onze critérios propostos foi excluído, tendo sido sugeridos sete novos critérios pelos participantes, que serão sujeitos a análise nas rondas subsequentes. Os resultados obtidos poderão servir de base a estudos mais aprofundados nesta área e contribuir para o debate sobre os critérios subjacentes ao processo de determinação de prioridades em saúde.

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OBJECTIVE: Detect of cardiac alterations in children with AIDS and compare their evolution with the administration of only one anti-retroviral and the recent cases who received drugs in combination. METHODS: We prospectively studied 47 children in 3 groups: group 1, 20 cases treated only with zidovudine; group 2, 10 patients treated initially with zidovudine and later with a combination of drugs and in group 3, 17 patients, who receiced two or three since the beginning. In all patients it was done chest X-ray, EKG and echocardiography every 6 months and after death complete pathological study. RESULTS: Among the 45 patients cases 26 (57%) were index cases. Malnutrition, diarrhea tachycardia, signs of congestive heart failure, pericardial effusion, abnormal ventricular repolarization and arrhythmias were more frequent in group 1. Echocardiographic abnormalities were present in 10 (50%) children of group 1. They were less frequent in the others two groups. In regard to the outcome in group 1, two patients had worsening of sings of cardiomyopaty and 4 died. Cardiac dysfunction in all cases of group 2 and 3 improved with the medication. CONCLUSION:- The children who received combination and their cardiac alterations had more favorable outcome than those who received only one drug.

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BACKGROUND: Tenofovir is associated with reduced renal function, but it is not clear whether there is a greater decline in renal function when tenofovir is co-administered with a boosted protease inhibitor rather than with a nonnucleoside reverse transcriptase inhibitor (NNRTI). METHODS: We calculated the estimated glomerular filtration rate (eGFR) for patients in the Swiss HIV Cohort Study. We estimated the difference in eGFR over time between first therapies containing tenofovir and either the NNRTI efavirenz or the protease inhibitors lopinavir (LPV/r) or atazanavir (ATV/r), both boosted with ritonavir. RESULTS: Patients on a first therapy of tenofovir co-administered with efavirenz (n  = 484), LPV/r (n = 269) and ATV/r (n =  187) were followed for a median of 1.7, 1.2 and 1.3 years, respectively. Relative to tenofovir and efavirenz, the estimated difference in eGFR for tenofovir and LPV/r was -2.6 ml/min per 1.73 m [95% confidence interval (CI) -7.3 to 2.2) during the first 6 months of therapy, then followed by a difference of 0.0 ml/min per 1.73 m (95% CI -1.1 to 1.1) for each additional 6 months of therapy. Relative to tenofovir and efavirenz, the estimated difference in eGFR for tenofovir and ATV/r was -7.6 ml/min per 1.73 m (95% CI -11.8 to -3.4) during the first 6 months of therapy, then followed by a difference of -0.5 ml/min per 1.73 m (95% CI -1.6 to 0.7) for each additional 6 months of therapy. CONCLUSION: Tenofovir with either boosted protease inhibitor leads to a greater initial decline in eGFR than tenofovir with efavirenz; this decline may be worse with ATV/r than with LPV/r.

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We consider different methods for combining probability forecasts. In empirical exercises, the data generating process of the forecasts and the event being forecast is not known, and therefore the optimal form of combination will also be unknown. We consider the properties of various combination schemes for a number of plausible data generating processes, and indicate which types of combinations are likely to be useful. We also show that whether forecast encompassing is found to hold between two rival sets of forecasts or not may depend on the type of combination adopted. The relative performances of the different combination methods are illustrated, with an application to predicting recession probabilities using leading indicators.

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Although some individual techniques of supervised Machine Learning (ML), also known as classifiers, or algorithms of classification, to supply solutions that, most of the time, are considered efficient, have experimental results gotten with the use of large sets of pattern and/or that they have a expressive amount of irrelevant data or incomplete characteristic, that show a decrease in the efficiency of the precision of these techniques. In other words, such techniques can t do an recognition of patterns of an efficient form in complex problems. With the intention to get better performance and efficiency of these ML techniques, were thought about the idea to using some types of LM algorithms work jointly, thus origin to the term Multi-Classifier System (MCS). The MCS s presents, as component, different of LM algorithms, called of base classifiers, and realized a combination of results gotten for these algorithms to reach the final result. So that the MCS has a better performance that the base classifiers, the results gotten for each base classifier must present an certain diversity, in other words, a difference between the results gotten for each classifier that compose the system. It can be said that it does not make signification to have MCS s whose base classifiers have identical answers to the sames patterns. Although the MCS s present better results that the individually systems, has always the search to improve the results gotten for this type of system. Aim at this improvement and a better consistency in the results, as well as a larger diversity of the classifiers of a MCS, comes being recently searched methodologies that present as characteristic the use of weights, or confidence values. These weights can describe the importance that certain classifier supplied when associating with each pattern to a determined class. These weights still are used, in associate with the exits of the classifiers, during the process of recognition (use) of the MCS s. Exist different ways of calculating these weights and can be divided in two categories: the static weights and the dynamic weights. The first category of weights is characterizes for not having the modification of its values during the classification process, different it occurs with the second category, where the values suffers modifications during the classification process. In this work an analysis will be made to verify if the use of the weights, statics as much as dynamics, they can increase the perfomance of the MCS s in comparison with the individually systems. Moreover, will be made an analysis in the diversity gotten for the MCS s, for this mode verify if it has some relation between the use of the weights in the MCS s with different levels of diversity

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Background and Objectives - Gynecological laparoscopy causes high postoperative morbidity, mainly due to occurrences such as nausea and vomiting. They result from a great multiplicity of etiologies and drugs used in anesthesia may function as contributing factors. Both the emetic properties of nitrous oxide and the efficacy of metoclopramide as antiemetic agent are controversial. This study was undertaken to determine the effects of both drugs, when used alone or in combination. Methods - Eighty three physical status ASA I and II women were studied. They were premedicated with midazolam before induction of anesthesia with alfentanil and propofol. Anesthesia was maintained with isoflurane with or without nitrous oxide in oxygen. Muscle relaxation was achieved with atracurium. There were 4 groups of patients: GI: midazolam, alfentanil, propofol, atracurium, isoflurane/oxygen; GII: midazolam, alfentanil, propofol, atracurium, isoflurane/nitrous oxide/oxygen; GIII: metoclopramide, midazolam, alfentanil, propofol, atracurium, isoflurane/oxygen; GIV: metoclopramide, midazolam, alfentanil, propofol, atracurium, isoflurane/nitrous oxide/oxygen. The incidence of nausea and vomiting was assessed both in the recovery room (RR) and in the ward. Results - There were no significant differences as regards age, weight and height of the patients and duration of anesthesia and surgery. Nausea and vomiting were more frequent in patients who received N2O (GII, 50%; GIV, 33%), as compared to those who didn't receive this agent (GI and GII, 9.5% and 14.35%, respectively). Metoclopramide decreased the incidence of nausea and vomiting in the recovery room, in patients who didn't receive N2O (GII). These patients remained in the recovery room for 90 minutes. Conclusions - N2O increases the incidence of nausea and vomiting and metoclopramide is effective in reducing these complications only in the recovery room.

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Abstract Background Remodeling of the extracellular matrix is one of the most striking features observed in the uterus during the estrous cycle and after hormone replacement. Versican (VER) is a hyaluronan-binding proteoglycan that undergoes RNA alternative splicing, generating four distinct isoforms. This study analyzed the synthesis and distribution of VER in mouse uterine tissues during the estrous cycle, in ovariectomized (OVX) animals and after 17beta-estradiol (E2) and medroxyprogesterone (MPA) treatments, either alone or in combination. Methods Uteri from mice in all phases of the estrous cycle, and animals subjected to ovariectomy and hormone replacement were collected for immunoperoxidase staining for versican, as well as PCR and quantitative Real Time PCR. Results In diestrus and proestrus, VER was exclusively expressed in the endometrial stroma. In estrus and metaestrus, VER was present in both endometrial stroma and myometrium. In OVX mice, VER immunoreaction was abolished in all uterine tissues. VER expression was restored by E2, MPA and E2+MPA treatments. Real Time PCR analysis showed that VER expression increases considerably in the MPA-treated group. Analysis of mRNA identified isoforms V0, V1 and V3 in the mouse uterus. Conclusion These results show that the expression of versican in uterine tissues is modulated by ovarian steroid hormones, in a tissue-specific manner. VER is induced in the myometrium exclusively by E2, whereas MPA induces VER deposition only in the endometrial stroma.

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BACKGROUND ; AIMS: Nonalcoholic steatohepatitis (NASH) is a frequent liver disease that can progress to cirrhosis and for which there is no recognized therapy. UDCA and vitamin E have been considered separately as therapeutic options and have not been shown to be effective. This study tested their combination. METHODS: Patients with elevated aminotransferase levels and drinking less than 40 g alcohol/week with biopsy-proven NASH were randomly assigned to receive UDCA 12-15 mg.kg-1.day-1 with vitamin E 400 IU twice a day (UDCA/Vit E), UDCA with placebo (UDCA/P), or placebo/placebo (P/P). After 2 years, they underwent a second liver biopsy. Biopsy specimens were collected, blinded, and scored by a single liver pathologist. RESULTS: Forty eight patients were included, 15 in the UDCA/Vit E group, 18 in the UDCA/P group, and 15 in the P/P group; 8 patients dropped out, none because of side effects. Baseline parameters were not significantly different between the 3 groups. Body mass index remained unchanged during the study. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels diminished significantly in the UDCA/Vit E group. Neither the AST nor the ALT levels improved in the P/P group and only the ALT levels in the UDCA/P group. Histologically, the activity index was unchanged at the end of the study in the P/P and UDCA/P groups, but it was significantly better in the UDCA/Vit E group, mostly as a result of regression of steatosis. CONCLUSIONS: Two years of treatment with UDCA in combination with vitamin E improved laboratory values and hepatic steatosis of patients with NASH. Larger trials are warranted.

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Low-micromolar concentrations of sulfite, thiosulfate and sulfide, present in synthetic wastewater or anaerobic digester effluent, were quantified by means of derivatization with monobromobimane, followed by HPLC separation with fluorescence detection. The concentration of elemental sulfur was determined, after its extraction with chloroform from the derivatized sample, by HPLC with UV detection. Recoveries of sulfide (both matrices), and of thiosulfate and sulfite (synthetic wastewater) were between 98 and 103%. The in-run RSDs on separate derivatizations were 13 and 19% for sulfite (two tests), between 1.5 and 6.6% for thiosulfate (two tests) and between 4.1 and 7.7% for sulfide (three tests). Response factors for derivatives of sulfide and thiosulfate, but not sulfite, were steady over a 13-month period during which 730 samples were analysed. Dithionate and tetrathionate did not seem to be detectable with this method. The distinctness of the elemental sulfur and the derivatizing-agent peaks was improved considerably by detecting elution at 297 instead of 263 nm. (C) 2002 Elsevier Science B.V. All rights reserved.

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Laboratory diagnosis of intestinal schistosomiasis mansoni can be accomplished through various methods of stool examination to detect parasites, ranging from the most classic tests (Kato-Katz) to several methods that are still undergoing validation. This study was conducted to assess two new parasite identification methods for diagnosing schistosomiasis mansoni in residents of a low endemic area in the municipality of Maranguape, in the state of Ceará, Brazil using the Kato-Katz method as a reference and serology (enzyme-linked immunosorbent assay) for the screening of patients. The Kato-Katz, the saline gradient method and the Helmintex® method parasite identification methods were employed only in subjects who exhibited positive serologic tests. The test results were then analysed and treatment of positive individuals was subsequently performed. After comparing the test results, we observed that the saline gradient method and the Helmintex® method were more effective in diagnosing schistosomiasis mansoni in the study area compared with the Kato-Katz method.