Psychomotor development index in children younger than 6 years from Argentine provinces.

Objective: To obtain a psychomotor development index (PDI) for each Argentine province.

Population And Methods: Using a national, probabilistic, and stratified sample of 13 323 male and female children younger than 6 years selected for the National Survey on Nutrition and Health (Encuesta Nacional de Nutrición y Salud, ENNyS 2004), we estimated the PDI per province based on compliance with 10 developmental milestones. The median age at attainment (median age) of each milestone was estimated adjusting a logistic regression.

Developmental tempo in children aged 0-5 years living under unfavourable environmental conditions.

Objective: To describe the dynamics of development along the early years of life among children living under unfavorable socioeconomic conditions.

Population And Methods: In 5401 children younger than 6 years old living in Florencio Varela and in the Matanza-Riachuelo River Basin (Matanza, Villa 21-24, Wilde, Villa Inflamable and Acuba), areas with a high proportion of families with unmet basic needs, a logistic regression analysis was used to estimate the median age at attainment of 13 psychomotor developmental milestones; differences between these ages and median age at attainment of milestones as per the national reference were plotted on the y-axis, while the median age as per the national reference was plotted on the x-axis.

Results: Three stages were observed: the first one between 0 and 270 days with normal development, in which the median age at attainment was similar to that of the national reference; a second one of progressive development delay; and a third one of recovery at 1260 days.

A New Distribution Family for Microarray Data.

The traditional approach with microarray data has been to apply transformations that approximately normalize them, with the drawback of losing the original scale. The alternative stand point taken here is to search for models that fit the data, characterized by the presence of negative values, preserving their scale; one advantage of this strategy is that it facilitates a direct interpretation of the results. A new family of distributions named gpower-normal indexed by p∈R is introduced and it is proven that these variables become normal or truncated normal when a suitable gpower transformation is applied.

Assessment of child psychomotor development in population groups as a positive health indicator.

Introduction: It is necessary to use health indicators describing the conditions of all individuals in a population, not just of those who have a disease or die.

Objectives: To introduce a method to collect population indicators of psychomotor development in children younger than 6 years old and show its results.

Population And Methods: Data were obtained from a cross-sectional assessment regarding compliance with 13 developmental milestones (selected from the national reference) conducted in 5465 children using five surveys administered by the Matanza-Riachuelo River Basin Authority in areas of this basin where a high proportion of families with unmet basic needs live.

A new variance stabilizing transformation for gene expression data analysis.

In this paper, we introduce a new family of power transformations, which has the generalized logarithm as one of its members, in the same manner as the usual logarithm belongs to the family of Box-Cox power transformations. Although the new family has been developed for analyzing gene expression data, it allows a wider scope of mean-variance related data to be reached. We study the analytical properties of the new family of transformations, as well as the mean-variance relationships that are stabilized by using its members.

Does serum cause lipid-droplet accumulation in bovine embryos produced in vitro, during developmental days 1 to 4?

Purpose: Serum supplementation has shown to have beneficial effects on in vitro bovine embryo development. However, it is often assumed that serum supplementation may produce mitochondrial damage and this damage would generate lipid accumulation, a major obstacle for cryopreservation. The aim of the present study is to investigate the previous assumptions in early embryonic stages.

Where statistics and molecular microarray experiments biology meet.

This review chapter presents a statistical point of view to microarray experiments with the purpose of understanding the apparent contradictions that often appear in relation to their results. We give a brief introduction of molecular biology for nonspecialists. We describe microarray experiments from their construction and the biological principles the experiments rely on, to data acquisition and analysis.