Aim: We aim was to compare the sagittal abdominal diameter (SAD) with waist circumference (WC) as a predictor of central obesity among adults and to identify the sensitivity and specificity of the best cut-off point for SAD. Methods: A cross-sectional study of 266 Brazilians adults (euthrophic and overweight), aged 31-84 years old, of which 89 men and 177 women, was carried out. Anthropometric measurements such as SAD, weight, height, waist and hip circumferences, waist and hip ratio, body mass index, body fat percentage were performed. Receiver Operating Characteristics (ROC) curve was used to identify the sensitivity and specificity of the best cut off point for SAD as a predictor of central obesity. Statistical analysis were considered significant with a value of p < 0.05. Results: The SAD measurement was positively correlated with WC for both genders, although stronger among overweight and obesity women (r = 0.71; p < 0.001 and r = 0.79; p < 0.001, respectively) than men. ROC curves identified the best cut-off points for SAD of 23.1 cm and 20.1 cm for men and women (96% and 85% sensitivity, 86% and 84% specificity, respectively). Conclusion: SAD measurement may be used as an anthropometric tool to identify central obesity among women for presenting adequate sensitivity and specificity.

Objetivo: Nuestro objetivo es comparar el diámetro abdominal sagital (DAS) con la circunferencia de la cintura (CC) como predictor de la obesidad central entre los adultos y para determinar la sensibilidad y la especificidad de la mejor punto de corte para el DAS. Métodos: Estudio transversal de 266 adultos brasileños (eutróficos y con sobrepeso), de entre 31-84 años de edad, de los cuales 89 hombres y 177 mujeres, se llevó a cabo. Las medidas antropométricas como la DAS, peso, talla, circunferencia de la cintura y cadera, relación cintura-cadera, índice de masa corporal, porcentaje de grasa corporal se llevaron a cabo. Receiver Operating Characteristics (ROC) curva se utilizó para determinar la sensibilidad y la especificidad del mejor punto de corte para el DAS como predictor de la obesidad central. El análisis estadístico se consideró significativo un valor de p < 0,05. Resultados: La medición del DAS se correlacionó positivamente con CC para ambos sexos, aunque más fuerte entre las mujeres con sobrepeso y obesidad (r = 0,71, p < 0,001, r = 0,79, p < 0,001, respectivamente) que los hombres. De curvas ROC identificado las mejores puntos de corte para el DAS de 23.1 cm y 20.1 cm para los hombres y mujeres (96% y el 85% de sensibilidad, 86% y el 84% de especificidad, respectivamente). Conclusión: La medición DAS puede ser utilizada como una herramienta antropométrica para identificar la obesidad central entre las mujeres para la presentación de la sensibilidad y especificidad adecuadas.

The presence of Staphylococcus aureus in the nasal cavities and pericatheter skin of peritoneal dialysis patients put them at high risk of developing peritonitis. However, it is not clear whether the presence of coagulase-negative staphylococci (CNS) in the nasal passages and skin of patients is related to subsequent occurrence of peritoneal infection. The aim of the present study was to verify the relationship between endogenous sources of S. aureus and CNS and occurrence of peritonitis in patients undergoing peritoneal dialysis. Thirty-two patients on peritoneal hemodialysis were observed for 18 months. Staphylococcus species present in their nasal passage, pericatheter skin and peritoneal effluent were identified and compared based on drug susceptibility tests and dendrograms, which were drawn to better visualize the similarity among strains from extraperitoneal sites as well as their involvement in the causes of infection. Out of 288 Staphylococcus strains isolated, 155 (53.8%) were detected in the nasal cavity, 122 (42.4%) on the skin, and 11 (3.8%) in the peritoneal effluent of patients who developed peritonitis during the study. The most frequent Staphylococcus species were CNS (78.1%), compared with S. aureus (21.9%). Among CNS, S. epidermidis was predominant (64.4%), followed by S. warneri (15.1%), S. haemolyticus (10.7%), and other species (9.8%). Seven (64%) out of 11 cases of peritonitis analyzed presented similar strains. The same strain was isolated from different sites in two (66%) out of three S. aureus infection cases. In the six cases of S. epidermidis peritonitis, the species that caused infection was also found in the normal flora. From these, two cases (33%) presented highly similar strains and in three cases (50%), it was difficult to group strains as to similarity. Patients colonized with multidrug-resistant S. epidermidis strains were more predisposed to infection. Results demonstrated that an endogenous source of S. epidermidis could cause peritonitis in peritoneal dialysis patients, similarly to what has been observed with S. aureus.

A variabilidade natural do solo dificulta a obtenção de valores que representem adequadamente as propriedades do solo em determinada área. O conhecimento do número mínimo de observações, que devem ser realizadas para representar, com um erro aceitável, uma propriedade ou característica do solo, é fundamental para que os resultados experimentais possam ser aplicados com segurança. No presente trabalho, comparou-se o método convencional (teste-t) com o método "bootstrap", com vistas em estimar o número de observações necessárias para calcular os parâmetros que caracterizam a relação entre a condutividade hidráulica e o teor de água do solo, determinada pelo método do perfil instantâneo. Realizou-se um experimento de drenagem num Latossolo Vermelho-Amarelo em Piracicaba (SP), numa parcela experimental com 45 pontos de observação distanciados de 1 m entre si. Observaram-se a umidade (com TDR) e o potencial mátrico (com tensiômetros) durante três semanas de redistribuição da água. Após processamento dos dados, o conjunto de valores mostrou uma distribuição não-normal, fazendo-se necessária a eliminação de "outliers" para a aplicação do método convencional, normalizando a distribuição. Assim, o uso do método tradicional só é recomendado após a confirmação da pertinência da eliminação dos "outliers". Ambos os métodos de análise requerem grande número de repetições, reafirmando que determinações da função condutividade hidráulica com poucas repetições não podem ser extrapoladas para áreas maiores.

Natural variability of soils makes it difficult to obtain values that adequately represent the soil properties within a certain area. The establishment of a minimum number of observations necessary to represent a soil property (with an acceptable error) is fundamental for the reliability of experimental results. In the present paper, the conventional t-test method has been compared with the bootstrap method, in order to estimate the number of observations needed to calculate the parameters that characterize the relation between hydraulic conductivity and soil water content, determined by the instantaneous profile method. A drainage experiment was realized in a red-yellow Oxisol (Hapludox) in Piracicaba, State of São Paulo, Brazil, on an experimental plot with 45 observation points in a straight line with a distance of one meter between points. Soil moisture was measured by TDR and the matric potential by tensiometers during three weeks of water redistribution. After data-processing, the parameters of the K(è) function presented a non-normal distribution and outliers had to be eliminated in order to normalize the data set for the t-test application. Therefore, the conventional method should only be used if the elimination of outliers is supposedly reasonable. Both analysis methods indicated the need of a high number of repetitions, reaffirming that hydraulic conductivity functions based on few repetitions should not be extrapolated to larger areas.