Decifrando o genoma em grande escala.

A determinação das funções gêni~~stem de~andado um grande avanço das ciências genômicas, cujas tecnologias concentram-se, principalmente, na geração e no estudo de uma grande quantidade de dados. O ponto de apoio para o entendimento da função gênica e da estrutura do genoína tem sido o sequenciamento de genomas completos e do genoma expresso em grande escala. Mapas físicos e genéticos têm sido integrados com informações genôrnicas e de expressão, resultando em bancos de dados públicos altamente informativos para diferentes espécies animais evegetais. Tais informações auxiliam em vários aspectos a análise·de expressão gênica, a determinação dos efeitos de processamento de éxons.e do número de cópias gênicas e cromossômicas, culminando na determinação das funções biológicas e do mecanismo de ação de vários genes. São descritos o surgimento de novas tecnologias e a evolução de algumas inovações já existentes, voltadas para a identificação de funções gênicas

Are the effects of unreal violent videogames pronounced when playing with a virtual reality system?

This study was conducted to analyze the short-term effects of violent electronic games, played with or without a virtual reality (VR) device, on the instigation of aggressive behavior. Physiological arousal (heart rate (HR)), priming of aggressive thoughts, and state hostility were also measured to test their possible mediation on the relationship between playing the violent game (VG) and aggression. The participants—148 undergraduate students—were randomly assigned to four treatment conditions: two groups played a violent computer game (Unreal Tournament), and the other two a non-violent game (Motocross Madness), half with a VR device and the remaining participants on the computer screen. In order to assess the game effects the following instruments were used: a BIOPAC System MP100 to measure HR, an Emotional Stroop task to analyze the priming of aggressive and fear thoughts, a self-report State Hostility Scale to measure hostility, and a competitive reaction-time task to assess aggressive behavior. The main results indicated that the violent computer game had effects on state hostility and aggression. Although no significant mediation effect could be detected, regression analyses showed an indirect effect of state hostility between playing a VG and aggressio

Improving Access and Quality in Early Childhood Development Programs: Experimental Evidence from The Gambia

We evaluate two experiments of early childhood development (ECD) programs in The Gambia: one increasing access to services, and another improving service quality. In the first experiment, new community-based ECD centers were introduced to randomly chosen villages that had no pre-existing structured ECD services. In the second experiment, a randomly assigned subset of existing ECD centers received intensive provider training. We find no evidence that either intervention improved average levels of child development. Exploratory analysis suggests that the first experiment, which increased access to community-based ECD services, led to declines in child development among children from less disadvantaged households

Evidence of Two Distinct Dynamic Critical Exponents in Connection with Vortex Physics

The dynamic critical exponent $z$ is determined from numerical simulations for the three-dimensional (3D) lattice Coulomb gas (LCG) and the 3D XY models with relaxational dynamics. It is suggested that the dynamics is characterized by two distinct dynamic critical indices $z_0$ and $z$ related to the divergence of the relaxation time $\tau$ by $\tau\propto \xi^{z_0}$ and $\tau\propto k^{-z}$, where $\xi$ is the correlation length and $k$ the wavevector. The values determined are $z_0\approx 1.5$ and $z\approx 1$ for the 3D LCG and $z_0\approx 1.5$ and $z\approx 2$ for the 3D XY model. It is argued that the nonlinear $IV$ exponent relates to $z_0$, whereas the usual Hohenberg-Halperin classification relates to $z$. Possible implications for the interpretation of experiments are pointed out. Comparisons with other existing results are discussed.Comment: to appear in PR