926 resultados para smooth transition regression model
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OBJECTIVE: To estimate the effects of combined spinal-epidural and traditional epidural analgesia on uterine basal tone and its association with the occurrence of fetal heart rate (FHR) abnormalities. METHODS: Seventy-seven laboring patients who requested pain relief during labor were randomly assigned to combined spinal-epidural (n=41) or epidural analgesia (n=36). Uterine contractions and FHR were recorded 15 minutes before and after analgesia. Uterine tone was evaluated with intrauterine pressure catheter. Primary outcomes were the elevation of baseline uterine tone and occurrence of FHR prolonged decelerations or bradycardia after analgesia. The influence of other variables such as oxytocin use, hypotension, and speed of pain relief were estimated using a logistic regression model. RESULTS: The incidence of all outcomes was significantly greater in the combined spinal-epidural group compared with epidural: uterine hypertonus (17 compared with 6; P=.018), FHR abnormalities (13 compared with 2; P<.01), and both events simultaneously (11 compared with 1; P<.01). Logistic regression analysis showed the type of analgesia as the only independent predictor of uterine hypertonus (odds ratio 3.526, 95% confidence interval 1.21-10.36; P=.022). For the occurrence of FHR abnormalities, elevation of uterine tone was the independent predictor (odds ratio 18.624, 95% confidence interval 4.46-77.72; P<.001). Regression analysis also found a correlation between decrease on pain scores immediately after analgesia and the estimated probability of occurrence of hypertonus and FHR abnormalities. CONCLUSION: Combined spinal-epidural analgesia is associated with a significantly greater incidence of FHR abnormalities related to uterine hypertonus compared with epidural analgesia. The faster the pain relief after analgesia, the higher the probability of uterine hypertonus and FHR changes. CLINICAL TRIAL REGISTRATION: Umin Clinical Trials Registry, http://www.umin.ac.jp/ctr/index.htm, UMIN000001186
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Background: Widespread use of prostate-specific antigen screening has resulted in younger and healthier men being diagnosed with prostate cancer. Their demands and expectations of surgical intervention are much higher and cannot be adequately addressed with the classic trifecta outcome measures. Objective: A new and more comprehensive method for reporting outcomes after radical prostatectomy, the pentafecta, is proposed. Design, setting, and participants: From January 2008 through September 2009, details of 1111 consecutive patients who underwent robot-assisted radical prostatectomy performed by a single surgeon were retrospectively analyzed. Of 626 potent men, 332 who underwent bilateral nerve sparing and who had 1 yr of follow-up were included in the study group. Measurements: In addition to the traditional trifecta outcomes, two perioperative variables were included in the pentafecta: no postoperative complications and negative surgical margins. Patients who attained the trifecta and concurrently the two additional outcomes were considered as having achieved the pentafecta. A logistic regression model was created to evaluate independent factors for achieving the pentafecta. Results and limitations: Continence, potency, biochemical recurrence-free survival, and trifecta rates at 12 mo were 96.4%, 89.8%, 96.4%, and 83.1%, respectively. With regard to the perioperative outcomes, 93.4% had no postoperative complication and 90.7% had negative surgical margins. The pentafecta rate at 12 mo was 70.8%. On multivariable analysis, patient age (p = 0.001) was confirmed as the only factor independently associated with the pentafecta. Conclusions: A more comprehensive approach for reporting prostate surgery outcomes, the pentafecta, is being proposed. We believe that pentafecta outcomes more accurately represent patients` expectations after minimally invasive surgery for prostate cancer. This approach may be beneficial and may be used when counseling patients with clinically localized disease. (C) 2011 European Association of Urology. Published by Elsevier B. V. All rights reserved.
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Background: The Flutter (R) VRP1 combines high frequency oscillation and positive expiratory pressure (PEP). Objective: To separately evaluate the effect of the Flutter (R) VRP1 components (high frequency oscillation and PEP) on mucus transportability in patients with bronchiectasis. Methods: Eighteen patients with bronchiectasis received sessions with the Flutter (R) VRP1 or PEP for 30 min daily in a randomized, crossover study. The treatment duration was four weeks with one of the therapies, one week of a ""wash-out"" period and followed by four more weeks with the other treatment. Weekly secretion samples were collected and evaluated for mucociliary relative transport velocity (RTV), displacement in a simulated cough machine (SCM) and contact angle measurement (CAM). For the proposed comparisons, a linear regression model was used with mixed effects with a significance level of 5%. Results: The Flutter (R) VRP1 treatment resulted in greater displacement in SCM and lower CAM when comparing results from the first (9.6 +/- 3.4 cm and 29.4 +/- 5.7 degrees, respectively) and fourth weeks of treatment (12.44 +/- 10.5 cm and 23.28 +/- 6.2, respectively; p < 0.05). There was no significant difference in the RTV between the treatment weeks for either the Flutter (R) VRP1 or PEP. Conclusion: The use of the Flutter (R) VRP1 for four weeks is capable of altering the respiratory secretion transport properties, and this alteration is related to the high frequency oscillation component. (C) 2011 Elsevier Ltd. All rights reserved.
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Our aim was to estimate the prevalence of nocturnal awakening with headache (NAH) in the population of Sao Paulo City according to gender, age (20-80 years old) and socioeconomic classes and its relationship to sleep disorders, sleep parameters, anxiety, depression, fatigue, life quality and obesity. We used a population-based survey with a representative three-stage cluster sample. Questionnaires and scales were applied face-to-face, and polysomnography was performed in 1101 volunteers, aged 42 +/- 14 years, 55% women. The complaint of NAH occurring at least once a week had a prevalence of 8.4%, mostly in women, obese subjects and those aged 50-59 years-old. We observed associations of NAH with insomnia, restless leg syndrome (RLS), nightmares and bruxism, but not obstructive sleep apnea syndrome. In a logistics regression model, risk factors for NAH were female gender, odds ratio (OR) (95% confidence interval [CI]) 4.5 (2.8-7.3); obesity, OR 1.9 (1.1-3.3); age between 50 and 59 years, OR 2.4 (1.2-4.7); severe anxiety, OR 8.1 (3.6-18.1); RLS, 2.7 (1.2-5.6); and nightmares, 2.2 (1.3-3.7). Our study shows that NAH was highly prevalent in the population of Sao Paulo and suggests that this phenomenon has specific characteristics with specific risk factors: obesity, RLS and nightmares.
Willingness to pay for conservation of the Asian elephant in Sri Lanka: A contingent valuation study
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Results from a CVM survey of willingness to pay for the conservation of the Asian elephant of a sample of urban residents in three selected housing schemes in Colombo, the capital of Sri Lanka, are reported. Face– to–face surveys were conducted using an interview schedule. A non-linear logit regression model was constructed to analyse the respondents’ responses for the payment principle questions and to identify the factors that influence their responses. We investigate whether urban residents’ WTP for the conservation of elephants is sufficient to compensate farmers for the damage caused by elephants, and consequently to raise farmers’ tolerance of the presence of elephants on the farming fields. We find that beneficiaries (the urban residents) could compensate losers (the farmers in the HEC affected areas) and be better off than in the absence of elephants in Sri Lanka. This suggests that there is a strong economic case for the conservation of the wild elephant population in Sri Lanka. However, we have insufficient data to determine Sri Lanka’s optimal elephant population in the Kaldor-Hicks sense.
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Reports results from a contingent valuation survey of willingness to pay for the conservation of the Asian elephant of a sample of urban residents living in three selected housing schemes in Colombo, the capital of Sri Lanka. Face–to–face surveys were conducted using an interview schedule. A non-linear logit regression model is used to analyse the respondents’ responses for the payment principle questions and to identify the factors that influence their responses. We investigate whether urban residents’ willingness to pay for the conservation of elephants is sufficient to compensate farmers for the damage caused by elephants. We find that the beneficiaries (the urban residents) could compensate losers (the farmers in the areas affected by human–elephant conflict) and be better off than in the absence of elephants in Sri Lanka. Therefore, there is a strong economic case for the conservation of the wild elephant population in Sri Lanka. However, we have insufficient data to determine the optimal level of this elephant population in the Kaldor-Hicks sense. Nevertheless, the current population of elephant in Sri Lanka is Kaldor-Hicks preferable to having none.
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The genetic and environmental contributions to educational attainment in Australia are examined using a multiple regression model drawn from the medical research literature. Data from a large sample of Australian twins are analysed. The findings indicate that at least as much as 50 percent and perhaps as much as 65 percent of the variance in educational attainments can be attributed to genetic endowments. It is suggested that only around 25 percent of the variance in educational attainments may be due to environmental factors, though this contribution is shown to be around 40 percent when adjustments for measurement error and assortative mating are made. The high fraction of the observed variation in educational attainments due to genetic differences is consistent with results reported by Heath et al. (Heath, A.C., Berg, K., Eaves, L.J., Solaas, M.H., Corey, L.A., Sundet, J., Magnus, P., Nance, W.E., 1985. Education policy and the heritability of educational attainment. Nature 314(6013), 734-736.), Tambs et al. (Tambs, K., Sundet, J.M., Magnus, P., Berg, K., 1989. Genetic and environmental contributions to the covariance between occupational status, educational attainment and IQ: a study of twins. Behavior Genetics 19(2), 209-222.), Vogler and Fulker (Vogler, G.P., Fulker, D.W., 1983. Familial resemblance for educational attainment. Behavior Generics 13(4), 341-354.) and Behrman and Taubman (Behrman, J., Taubman, P., 1989. Is schooling mostly in the genes? Nature-nurture decomposition using data on relatives. Journal of Political Economy 97(6), 1425-1446.), suggesting that the finding is robust. (C) 2001 Elsevier Science Ltd. All rights reserved.
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This paper examines the trade relationship between the Gulf Cooperation Council (GCC) and the European Union (EU). A simultaneous equation regression model is developed and estimated to assist with the analysis. The regression results, using both the two stage least squares (2SLS) and ordinary least squares (OLS) estimation methods, reveal the existence of feedback effects between the two economic integrations. The results also show that during times of slack in oil prices, the GCC income from its investments overseas helped to finance its imports from the EU.
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Background: Germline mutations in the CDKN2A gene, which encodes two proteins (p16INK4A and p14ARF), are the most common cause of inherited susceptibility to melanoma. We examined the penetrance of such mutations using data from eight groups from Europe, Australia and the United States that are part of The Melanoma Genetics Consortium Methods: We analyzed 80 families with documented CDKN2A mutations and multiple cases of cutaneous melanoma. We modeled penetrance for melanoma using a logistic regression model incorporating survival analysis. Hypothesis testing was based on likelihood ratio tests. Covariates included gender, alterations in p14APF protein, and population melanoma incidence rates. All statistical tests were two-sided. Results: The 80 analyzed families contained 402 melanoma patients, 320 of whom were tested for mutations and 291 were mutation carriers. We also tested 713 unaffected family members for mutations and 194 were carriers. Overall, CDKN2A mutation penetrance was estimated to be 0.30 (95% confidence interval (CI) = 0.12 to 0.62) by age 50 years and 0.67 (95% CI = 0.31 to 0.96) by age 80 years. Penetrance was not statistically significantly modified by gender or by whether the CDKN2A mutation altered p14ARF protein. However, there was a statistically significant effect of residing in a location with a high population incidence rate of melanoma (P = .003). By age 50 years CDKN2A mutation penetrance reached 0.13 in Europe, 0.50 in the United States, and 0.32 in Australia; by age 80 years it was 0.58 in Europe, 0.76 in the United States, and 0.91 in Australia. Conclusions: This study, which gives the most informed estimates of CDKN2A mutation penetrance available, indicates that the penetrance varies with melanoma population incidence rates. Thus, the same factors that affect population incidence of melanoma may also mediate CDKN2A penetrance.
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Introdução: Há cerca de duas décadas, a tuberculose (TB) foi considerada pela Organização Mundial de Saúde (OMS) como uma doença em estado de emergência em todo o mundo. Atualmente, apesar de todas as ações de controle da doença, ainda trata-se de um importante problema de saúde pública, apresentando forte relação com questões socioeconômicas, o que acarreta no maior adoecimento em grupos específicos, tais como a população privada de liberdade. Os dados de tuberculose em populações vulneráveis podem atingir índices ainda mais altos e por isso preocupante. Objetivos: Analisar as características clínicas e epidemiológicas associadas com os desfechos do tratamento da tuberculose na população privada de liberdade do Brasil, registrado no Sistema de Informação de Agravos de Notificação (SINAN), de 2007 a 2011; conhecer a taxa de incidência e de mortalidade por tuberculose na população privada de liberdade do Espírito Santo, de julho de 2009 a julho de 2010; e identificar as características clínicas e epidemiológicas dos casos diagnosticados de tuberculose na população privada de liberdade do Espírito Santo, de julho de 2009 a julho de 2010. Métodos: A população do estudo consistiu em presos diagnosticados com tuberculose identificados através do SINAN, entre janeiro de 2007 e dezembro de 2011 e dos casos diagnosticados de tuberculose na população prisional do Espírito Santo no período de 1º de julho de 2009 a 30 de junho de 2010. O teste de qui-quadrado de Pearson e o modelo de regressão polinomial foram utilizados na analise, além de estatística descritiva, por meio de tabelas e gráficos. Resultados: Em relação pacientes com TB na população privada de liberdade do Brasil, nota-se que os presos que abandonaram o tratamento eram mais jovens (P <0,001), com menor escolaridade (P <0,001) e maior probabilidade de alcoolismo (P < 0,001), eram mais propensos a ter TB recorrente ou recidiva (P < 0,001) e eles não estavam sob tratamento diretamente observado (TDO) (P < 0,001), comparados com aqueles que completaram o tratamento da tuberculose. Aqueles que morreram de tuberculose tendem a ter idade ⩾ 43 anos (P < 0,001) e alcoolistas (P < 0,001), também eram mais propensos a tipo de tratamento desconhecido (P <0,001) e apresentar tuberculose pulmonar e tuberculose extrapulmonar (TBEP). Presos que desenvolveram tuberculose multidroga resistente (TB-MDR) foram mais propensos a 9 experiência de recorrência de TB, retorno após abandono e transferência de local de tratamento. Além disso, observou-se 167 casos de tuberculose (taxa de incidência de 1962,6 por 100 mil presos) no Espírito Santo. O sexo masculino apresentou maior número de pacientes, assim como a faixa etária de 25 a 36 anos e a forma clínica pulmonar. Destaca-se que 109 (65,3%) pacientes tiveram alta por cura, ocorrendo dois óbitos durante o período, sendo a taxa de mortalidade por tuberculose de 11,7 por 100 mil presos. A maior incidência da tuberculose foi em pacientes localizados nas unidades prisionais da Região Metropolitana e um pequeno número de casos ocorreu em outros locais externos às unidades prisionais. Conclusão: Nossos resultados destacam a necessidade de melhorar as políticas de controle da TB nas penitenciárias, bem como os desfechos do tratamento de presos a fim de impedir a transmissão para outros presos, seus familiares e profissionais de saúde.
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A absorção de água por carcaças de frango na etapa de pré-resfriamento da linha abate representa uma característica de qualidade importante relacionada ao rendimento do produto final. Uma forma de manter o padrão de qualidade de um produto é garantir que as etapas do processo sejam estáveis e replicáveis. Ao empregar o Controle Estatístico de Processo (CEP) é possível obter estabilidade e melhorias nos processos, por meio da redução da variabilidade. Neste contexto, o objetivo deste trabalho foi a aplicação de gráficos de controle, análise de correlação, estatística descritiva, testes de hipóteses e regressão linear múltipla na linha de abate de um abatedouro-frigorífico de aves para monitorar a variabilidade da absorção de água pelas carcaças de frango após a etapa de pré-resfriamento. Como resultado, verificou-se que o teor de absorção de água das carcaças de frango apresentou elevada variabilidade, sendo que 10% (8/80) das carcaças apresentaram absorção de água superior ao limite de 8% definido pela legislação brasileira. Do total de 16 variáveis de entrada analisadas, as mais impactantes no teor de absorção de água foram o “tempo de retenção da carcaça no pré-chiller” e o “tempo de espera da carcaça após a etapa de gotejamento”. Entretanto, o modelo de regressão obtido apresentou baixa correlação (R²=0,16) que foi associada à elevada variabilidade da variável-resposta. Os resultados da estatística descritiva demonstraram que as variáveis de entrada também apresentaram elevada variabilidade, com coeficiente de variação entre 7,95 e 63,5%. Verificou-se, pela análise dos gráficos de controle de medida individual e da amplitude móvel, que 15 das 16 variáveis de entrada se apresentaram fora de controle estatístico assim como a variável-resposta. Baseado no fluxograma e na descrição das etapas da linha de abate, previamente realizados, atribuiu-se à falta de padronização na condução das etapas e de procedimentos para o controle de qualidade das operações na linha de abate como fatores relevantes que poderiam estar associados à presença de causas especiais no processo. Concluiu-se que para reduzir a elevada variabilidade das variáveis e eliminar as causas especiais presentes são necessários ajustes operacionais para, dessa forma, obter um processo mais estável e mais uniforme garantindo o padrão de qualidade das carcaças de frango em relação ao teor de absorção de água.
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O objetivo deste estudo é estimar a prevalência de transtornos mentais de acordo com a situação de emprego por sexo, analisar associações entre os transtornos mentais e situação de emprego, bem como entre a busca de tratamento e situação de emprego dentre os respondentes com transtornos mentais nos últimos 12 meses. Além disso, pretende-se analisar a perda de dias de trabalho devido ao absenteísmo e ao presenteísmo associando-os com os transtornos mentais, dentre os trabalhadores. Os dados foram analisados a partir do Estudo São Paulo Megacity, um estudo de base populacional que avaliou os transtornos mentais em uma amostra probabilística de 5.037 adultos residentes na Região Metropolitana de São Paulo, utilizando a versão do Composite International Diagnostic Interview da Organização Mundial de Saúde. A amostra foi dividida em grupos de acordo com a situação de trabalho – trabalhadores, economicamente inativos e desempregados. A prevalência dos transtornos mentais foi estimada estratificada por sexo, bem como, as associações com as situações de emprego, características sócio-demográficas e procura por tratamento. O número médio de dias perdidos por absenteísmo e presenteísmo na população de trabalhadores foi estimado baseado na Escala de Avaliação de Incapacidade Organização Mundial de Saúde. Os efeitos a nível populacional e os custos financeiros também foram estimados. As associações foram medidas pelo Odds Ratio e calculada através do modelo de regressão logística multinomial. Do total da amostra (n= 5.035), 63% eram trabalhadores, 25% economicamente inativos e 12% desempregados. Os trabalhadores foram associados ao sexo masculino, menor idade, maior número de anos estudados e maior renda. As mulheres apresentaram maior prevalência de transtornos de humor e ansiedade. Os homens foram associados a qualquer transtorno mental, transtorno de humor e transtorno de ansiedade, as mulheres foram associadas a situação de emprego economicamente inactivas e desempregadas. Os homens cuja situação de emprego era trabalhador mostrou maiores prevalências nos transtornos de impulso-controle e nos transtornos por uso de substâncias psicoativas. As mulheres cuja situação de emprego era trabalhador e os homens cuja situação de emprego era economicamente inativos, tiveram maiores prevalências de transtornos mentais. Dentre respondentes com algum transtorno mental, os respondentes economicamente inativos apresentaram associação com a procura de tratamento de saúde geral e de saúde mental. A presença de algum transtorno mental foi associado com 26,8 dias/ano devido ao absenteísmo, 92,2 dias/ano devido ao presenteísmo e 125,9 dias/ano de perda total de trabalho. Os custos anuais da perda de trabalho foram estimados em R$ 2,6 bilhões por ano, correspondentes a R$ 690 milhões por ano devido ao absenteísmo, e R$ 1,9 bilhões por ano devido ao presenteísmo. Nossos resultados fornecem importantes informações epidemiológicas sobre os transtornos mentais e o impacto no trabalho que devem ser levadas em consideração na definição de prioridades para os cuidados em saúde e alocação de recursos.
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This study analyses the determinants of the derivative instruments disclosure level by Portuguese listed companies. It is built a disclosure index to measure the disclosure level using the Consolidated Annual Reports for 2008. The hypotheses have been tested through a linear regression model using the disclosure index as the dependent variable and companies’ characteristics as independent variables. Multivariate results suggest that firm size, quality of the external auditor, belonging to PSI 20, the market to book value ratio and the percentage of capital hold by the board of directors are associated with the disclosure level.
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This study aimed to evaluate the efficiency of multiple centroids to study the adaptability of alfalfa genotypes (Medicago sativa L.). In this method, the genotypes are compared with ideotypes defined by the bissegmented regression model, according to the researcher's interest. Thus, genotype classification is carried out as determined by the objective of the researcher and the proposed recommendation strategy. Despite the great potential of the method, it needs to be evaluated under the biological context (with real data). In this context, we used data on the evaluation of dry matter production of 92 alfalfa cultivars, with 20 cuttings, from an experiment in randomized blocks with two repetitions carried out from November 2004 to June 2006. The multiple centroid method proved efficient for classifying alfalfa genotypes. Moreover, it showed no unambiguous indications and provided that ideotypes were defined according to the researcher's interest, facilitating data interpretation.
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As the amount of debt has gradually increased, particularly in recent years, Portugal is currently one of the European countries exhibiting one of the highest levels of overall indebtedness, including in both sovereign and private sectors. Indeed, this condition is the outcome of increasing levels of debt assumed not only by the government, but also by companies and families, being the later mostly due to mortgage loans and due charges. This paper focuses on the study of borrowing by Portuguese households. The research has been made in respect to the notion of debt, the consequences of recent developments in debt, among other factors. In order to analyse the factors that are most associated with debt, a study was developed using two multiple regression models, one using a longer time series and another shorter, evaluating the effect of several variables, such as consumption, savings, unemployment, inflation and interest rates, in order to check whether they could be associated with a higher level of debt.