Detecting stable phase structures in EEG signals to classify brain activity amplitude patterns

Obtaining an electrocorticograms （ECoG） signal requires an invasive procedure in which brain activity is recorded from the cortical surface. In contrast, obtaining electroencephalograms （EEG） recordings requires the non-invasive procedure of recording the brain activity from the scalp surface, which allows EEG recordings to be performed more easily on healthy humans. In this work, a technique previously used to study spatial-temporal patterns of brain activity on animal ECoG was adapted for use on EEG. The main issues are centered on solving the problems introduced by the increment on the interelectrode distance and the procedure to detect stable frames. The results showed that spatial patterns of beta and gamma activity can also be extracted from the EEG signal by using stable frames as time markers for feature extraction. This adapted technique makes it possible to take advantage of the cognitive and phenomenological awareness of a normal healthy subject.     

"Going Beyond the Call of Doula": A Grounded Theory Analysis of the Diverse Roles Community-Based Doulas Play in the Lives of Pregnant and Parenting Adolescent Mothers

This article presents some of the most salient qualitative results from a larger program evaluation of pregnant and parenting adolescents who participated in a community-based doula program. Using grounded theory analysis, seven problem-solving strategies emerged that doulas apply in helping pregnant and parenting adolescents navigate multiple social and health settings that often serve as barriers to positive maternal- and child-health outcomes. The ethnographic findings of this study suggest that the doulas provide valuable assistance to pregnant and parenting adolescents by addressing social-psychological issues and socio-economic disparities. "Diverse role-taking" results in doulas helping pregnant adolescents navigate more successfully through fragmented social and health service systems that are less supportive of low-income adolescents, who are often perceived to be draining scarce resources. The findings have implications for the roles of community-based doulas assigned to low-income adolescents of color seeking to overcome obstacles and attain better educational and economic opportunities.     

Too late for talent to kick in? The relative age effect in Argentinian male football

Does a young football (soccer) player’s birthdate affect his prospects in the sport? Scholars have found a correlation between early births in the competition year among young players within the same cohort and improved chances in sports as they advance to other stages. This article is one of the first studies to ask this question about a male premier league in Latin America – the Argentinian ‘A’ league. It uses a large-N data-set of all players in the period 2000–2012, around 3000 players. The article finds a large effect of the player’s relative age on his prospect to become a professional, though the effect is only present in the case of Argentinian-born players. The effect evaporates once a set of measures are employed to compare professional players with one another. The article contributes to the discussion of the biased effect of seemingly neutral institutional policies, and its conclusions may shed light in other areas.     

The Impact of Neighborhood,Family, and Individual Risk Factors on Toddlers’ Disruptive Behavior

Disadvantaged neighborhoods confer risk for behavior problems in school‐aged children but their impact in toddlerhood is unknown. Relations between toddlers’ disruptive behavior and neighborhood disadvantage, family disadvantage, violence or conflict exposure, parent depressive symptoms, and parenting behavior were examined using multilevel, multigroup (girl–boy) models. Participants were 1,204 families (mean child age = 24.7 months). Unique associations between disruptive behavior and all risk factors were observed, but the effect of neighborhood disadvantage was negligible when all of the more proximal factors were accounted for. The results suggest both that children in disadvantaged neighborhoods are at greater risk of behavior problems than children in nondisadvantaged neighborhoods and that optimal prevention/intervention work with these children will attend to proximal risk factors.     

Factors Contributing to Scholarly Productivity of Assistant Professors in Counseling

Doctoral research training and faculty departmental research culture were explored in relation to research interest, self‐efficacy, and productivity among 49 counselor education assistant professors. Doctoral research training environment consistently held strong positive relationships with research interest and self‐efficacy, suggesting that a solid foundation in research at the doctoral level is imperative for initial research productivity.     

A comparison of successful and unsuccessful placements of youths with mental handicaps into competitive employment

Abstract

We compared 54 matched pairs of high school students and young adults with mental retardation. One member of each pair had remained successfully employed for 10 or more hours per week at minimum wage or better for at least 6 months, and the other had not. Placement counselors, trainers, or supervisors completed case study questionnaires about their students (or clients). The results indicated successful placements in a variety of positions and communities across the nation. The most important elements contributing to this success are placement agency follow‐up support; home support; the individual's job skills, social ability, and match to job demands; the creativity and persistence of the placement specialist; incentive to employers (e.g., tax credits and employment subsidies) and employer's support of the placement.     

A Tutorial in Bayesian Potential Outcomes Mediation Analysis

Statistical mediation analysis is used to investigate intermediate variables in the relation between independent and dependent variables. Causal interpretation of mediation analyses is challenging because randomization of subjects to levels of the independent variable does not rule out the possibility of unmeasured confounders of the mediator to outcome relation. Furthermore, commonly used frequentist methods for mediation analysis compute the probability of the data given the null hypothesis, which is not the probability of a hypothesis given the data as in Bayesian analysis. Under certain assumptions, applying the potential outcomes framework to mediation analysis allows for the computation of causal effects, and statistical mediation in the Bayesian framework gives indirect effects probabilistic interpretations. This tutorial combines causal inference and Bayesian methods for mediation analysis so the indirect and direct effects have both causal and probabilistic interpretations. Steps in Bayesian causal mediation analysis are shown in the application to an empirical example.     

Intrafirm diffusion of new technologies: an empirical application

Research on the diffusion of new technologies has centred on the study of the interfirm rate of diffusion, paying much less attention to intrafirm aspects. This paper attempts to overcome this gap in the literature by analysing the factors that influence the speed with which a new technology, the ATM, is fully adopted. The data over which the hypotheses are tested belongs to the Spanish savings banks market. The results show that the rate of intrafirm diffusion is explained by innovation, firm and market characteristics. In testing our hypotheses we make use of both traditional methods and survival analysis techniques.     

Are returns to education on the decline in Venezuela and does Mission Sucre have a role to play?

Anecdotal evidence points to a falling standard of living for the educated in Venezuela. During this same period, President Hugo Chávez implemented several education reforms. We focus on a major university education reform known as Mission Sucre and its potential impact on returns to university education. First, we show that returns to education decreased significantly in Venezuela from 2002 to 2008. Subsequently, we explore the impact of the program on non-program participants and provide evidence that a substantial part of the falling returns at the tertiary level can be linked to Mission Sucre. Our results suggest that the reform created a negative externality on students who did not participate in the program, leading to a 2.7 percentage point decline in returns to university education for non-Mission Sucre students in the 23–28 age cohort.