10 research outputs found
Is disruption theory wearing new clothes or just naked? Analyzing recent critiques of disruptive innovation theory
Escala de atitudes frente ao uso de álcool: descrevendo seus parâmetros psicométricos
Este estudo objetivou conhecer evidências de validade e consistência interna da Escala de Atitudes frente ao Uso de Álcool (EAFUA). Participaram 259 estudantes universitários de João Pessoa, com idade média de 21 anos, a maioria mulheres (65,6%), que responderam perguntas demográficas e preencheram a EAFUA. Esta é composta por quatro adjetivos bipolares (positivo/negativo; gosto/desgosto; bom/ruim e desejável/indesejável), respondidos em escala de 9 pontos (-4 a +4). Uma análise de componentes principais indicou um componente geral que explicou 82,3% da variância total; seu alfa de Cronbach foi 0,93. A análise fatorial confirmatória reuniu índices de ajuste adequados para essa medida, corroborando sua estrutura unidimensional. Observaram-se diferenças de gênero nessa medida, que foi mais fortemente correlacionada com o uso de álcool (validade convergente) do que com o uso de maconha (validade discriminante). Esses resultados apóiam a adequação da EAFUA, portanto, esta poderá ser utilizada para conhecer o grau de favorabilidade ao uso de álcool entre adultos jovens
A Decision Theoretic and Prototype Conceptualization of Possible Selves: Implications for the Prediction of Risk Behavior
Coupling between neuronal activity and microcirculation: implications for functional brain imaging
In the neocortex, neurons with similar response properties are often clustered together in column-like structures, giving rise to what has become known as functional architecture—the mapping of various stimulus feature dimensions onto the cortical sheet. At least partially, we owe this finding to the availability of several functional brain imaging techniques, both post-mortem and in-vivo, which have become available over the last two generations, revolutionizing neuroscience by yielding information about the spatial organization of active neurons in the brain. Here, we focus on how our understanding of such functional architecture is linked to the development of those functional imaging methodologies, especially to those that image neuronal activity indirectly, through metabolic or haemodynamic signals, rather than directly through measurement of electrical activity. Some of those approaches allow exploring functional architecture at higher spatial resolution than others. In particular, optical imaging of intrinsic signals reaches the striking detail of ∼50 μm, and, together with other methodologies, it has allowed characterizing the metabolic and haemodynamic responses induced by sensory-evoked neuronal activity. Here, we review those findings about the spatio-temporal characteristics of neurovascular coupling and discuss their implications for functional brain imaging, including position emission tomography, and non-invasive neuroimaging techniques, such as funtional magnetic resonance imaging, applicable also to the human brain