Obediencia institucional en el laboratorio

Resumen

La presente investigación consistió en una réplica de los paradigmas experimentales de Milgram y Darley y Latané sobre conformidad y conducta de ayuda. Se utilizaron 28 S divididos en un grupo de control y uno experimental. La V.I. era la presencia o ausencia de una supuesta víctima que, en una estancia contigua, recibía descargas eléctricas contra su voluntad. La V.D. estudiada era la obediencia o no a las instrucciones del experimentador por parte de los S en ambas situaciones. Los resultados confirman los de anteriores trabajos al observarse altos porcentajes de conductas conformistas. Por último se discuten tales datos en base a su relevancia ecológica.     

Highly fluorescent silver nanofluids with ferroelectric molecules

Highly fluorescent silver nanoparticles (Ag-NPs), soluble in a ferroelectric host of polymer molecules such as poly(vinylidene fluoride) (PVF₂), have been created in the form of nanofluids. The content of Ag-NPs (flocculates) is varied in steps 0.1–0.2 wt% up to a value of 5.0 wt% in tailoring a broad green emission band over 520–620 nm out of a hybrid percolation Ag–PVF₂ composite. A maximum intensity arises in this band at as small a percolation threshold as ～0.1 wt% Ag-NPs. It contains three distinct bands of peak values 541, 565, and 582 nm in an Ag-NPs tunable response of the localized surface plasmons. The emission-dependent anti-Stokes excitation spectrum contains a similar group of three bands 348, 401, and 421 nm. For Ag-contents above 0.1 wt%, interdependent intensities in the emission and excitation bands drop rapidly by as much as five times, conferring a metal–polymer percolation network. The results open wide applications for biological labels and light emitters using such nanofluids.     

Ab initio study of Heusler alloys Co2XY (X = Cr,Mn, Fe; Y = Al,Ga) under high pressure

The structural, electronic, and magnetic properties of ferromagnetic Heusler alloys Co₂XY (X?=?Cr, Mn, Fe; Y?=?Al, Ga) have been investigated by means of the all-electron full-potential linearized augmented plane wave method within the generalized gradient approximation for the exchange and correlation potential. The main focus of this study is to elaborate the changes brought about in the electronic and the magnetic properties by applied pressure. The calculated total spin magnetic moments of all the compounds are found to be in good agreement with experiments. Out of these compounds, Co₂CrAl is found to be perfectly half-metallic (HM) and the other compounds are found to be nearly HM. Thus the HM to metal transition was observed at 75?GPa pressure for Co₂CrAl and the nearly half-metal to half-metal transition was observed at 40?GPa and 18?GPa for Co₂CrGa and Co₂MnAl, respectively, while no transition is observed in other compounds under investigation. It can be clearly seen that pressure affects the minority spin states rather than the majority states, leading to a slight reconstruction of the minority spin states with a shift in the Fermi level driving the above-mentioned transition.     

Do ADHD and Executive Dysfunctions,Measured by the Hebrew Version of Behavioral Rating Inventory of Executive Functions (BRIEF), Completely Overlap?

The centrality of executive function deficits (EFD) in attention deficit/ hyperactivity disorder (ADHD) is well accepted albeit EFD is not synonymous with ADHD. The purpose of the present study was to examine the extent to which ADHD and EF overlap and to validate the Hebrew version of the Behavioral Rating Inventory of Executive Functions (BRIEF). Parents of 178 children with and without ADHD completed the BRIEF and the ADHD-Rating Scale. Significant differences were found between groups on each scale even after controlling for the other scale. Internal consistency analysis supported the reliability of the Hebrew version of the BRIEF. We conclude that ADHD and Executive Dysfunctions do not completely overlap.     

Within-person covariation of agentic and communal perceptions: Implications for interpersonal theory and assessment

Interpersonal theory identifies agency and communion as uncorrelated (orthogonal) dimensions, largely evidenced by research examining between-person analyses of single-occasion measures. However, longitudinal studies of interpersonal behavior demonstrated the within-person association of agency and communion is not orthogonal for many individuals, and between-person differences in these associations relate to adjustment. We applied a similar approach to investigate the association of interpersonal perceptions. 184 university students completed a 7-day event-contingent study of their interpersonal experiences. Using multilevel regression models, we demonstrated that agentic and communal perceptions were positively associated, and the strength of this within-person association was moderated by between-person scores of dependency and narcissism. We discuss the benefits of incorporating within-person interpersonal associations (termed interpersonal covariation) into interpersonal theory and assessment.     

Improvement in working memory is not related to increased intelligence scores

The acknowledged high relationship between working memory and intelligence suggests common underlying cognitive mechanisms and, perhaps, shared biological substrates. If this is the case, improvement in working memory by repeated exposure to challenging span tasks might be reflected in increased intelligence scores. Here we report a study in which 288 university undergraduates completed the odd numbered items of four intelligence tests on time 1 and the even numbered items of the same tests one month later (time 2). In between, 173 participants completed three sessions, separated by exactly one week, comprising verbal, numerical, and spatial short-term memory (STM) and working memory (WMC) tasks imposing high processing demands (STM–WMC group). 115 participants also completed three sessions, separated by exactly one week, but comprising verbal, numerical, and spatial simple speed tasks (processing speed, PS, and attention, ATT) with very low processing demands (PS-ATT group). The main finding reveals increased scores from the pre-test to the post-test intelligence session (more than half a standard deviation on average). However, there was no differential improvement on intelligence between the STM-WMC and PS-ATT groups.     

Learning to Troubleshoot: Multistrategy Learning of Diagnostic Knowledge for a Real-World Problem-Solving Task

This article presents a computational model of the learning of diagnostic knowledge, based on observations of human operators engaged in real-world troubleshooting tasks. We present a model of problem solving and learning in which the reasoner introspects about its own performance on the problem-solving task, identifies what it needs to learn to improve its performance, formulates learning goals to acquire the required knowledge, and pursues its learning goals using multiple learning strategies. The model is implemented in a computer system which provides a case study based on observations of troubleshooting operators and protocol analysis of the data gathered in the test area of an operational electronics manufacturing plant. The model not only addresses issues in human learning, but, in addition, is computationally justified as a uniform, extensible framework for multistrategy learning.     

Nonlinear Structured Growth Mixture Models in Mplus and OpenMx

Growth mixture models (GMMs; B. O. Muthén & Muthén, 2000; B. O. Muthén & Shedden, 1999) are a combination of latent curve models (LCMs) and finite mixture models to examine the existence of latent classes that follow distinct developmental patterns. GMMs are often fit with linear, latent basis, multiphase, or polynomial change models because of their common use, flexibility in modeling many types of change patterns, the availability of statistical programs to fit such models, and the ease of programming. In this article, we present additional ways of modeling nonlinear change patterns with GMMs. Specifically, we show how LCMs that follow specific nonlinear functions can be extended to examine the presence of multiple latent classes using the Mplus and OpenMx computer programs. These models are fit to longitudinal reading data from the Early Childhood Longitudinal Study–Kindergarten Cohort to illustrate their use.