Incremental exercise tests in master athletes and untrained older adults

This study aimed to analyze the impact of step-duration protocols, 1-min vs. 3-min, on cardiorespiratory responses to exercise, whatever the aerobic-fitness level of sedentary (65.5 +/- 2.3 years, n = 8) or highly fit (63.1 +/- 3.2 years, n = 19) participants. Heart rate and VO2 at the first and second ventilatory thresholds (VT1 ,VT2) and maximal exercise were not significantly different between the two protocols. In master athletes, the 3-min protocol elicited significantly lower ventilation at VT2 and maximal exercise (p < .01). In the latter, breathlessness was also lower at maximal exercise (p < .05) than in sedentary participants. In trained or sedentary older adults, VT1, VT2, and were not influenced by stage duration. According to the lower breathlessness and ventilation, however, the 3-min step protocol could be more appropriate in master athletes. In untrained participants, because the cardiorespiratory responses were similar with the two incremental exercise tests, either of them could be used.     

Remittances in Ghana: Origin, Destination and Issues of Measurement

Few studies on remittances have focused on sub-Saharan Africa. This paper analyses a nationwide survey of 5,998 households to determine the characteristics of both internal and overseas remittances in Ghana. Particular attention is paid to the poverty-alleviation potential of remittances. Furthermore, this study uses a smaller scale pilot project with a matched sample of senders and receivers of remittances to identify some problems with using household-level surveys to assess the volume and impact of overseas remittances, and offers some suggestions as to how to handle these problems. The paper estimates that foreign remittances may be three times as large as Bank of Ghana estimates, bringing Ghana on par with large remittance receiving countries such as the Philippines and Mexico. The paper concludes that while foreign remittances are larger in value, locally sent remittances reach poorer segments of the population. Both foreign and local remittances are unevenly geographically distributed, being received more in the centre and southern regions than in northern Ghana where the poorest regions are. The paper argues a need to study multiplier effects of foreign remittances, as these can be large and eventually accrue to rural populations.     

Personal Identity Processes from Adolescence Through the Late 20s: Age Trends,Functionality, and Depressive Symptoms

Personal identity formation constitutes a crucial developmental task during the teens and 20s. Using a recently developed five‐dimensional identity model, this cross‐sectional study (N = 5834) investigated age trends from ages 14 to 30 for different commitment and exploration processes. As expected, results indicated that, despite some fluctuations over time, commitment processes tended to increase in a linear fashion. Exploration in breadth and exploration in depth were characterized by quadratic trends, with the highest levels occurring in emerging adulthood. Further, the functionality of these identity processes, and especially of exploration, changed over time. Exploration in breadth and exploration in depth were strongly related to commitment processes especially in adolescence and emerging adulthood, but these exploration processes became increasingly associated with ruminative exploration and depressive symptoms in the late 20s. Theoretical implications and suggestions for future research are outlined.     

Size and distribution trade-offs for the leximin ordering

A relative invariant and an absolute invariant inequality ordering satisfying extreme bottom-sensitivity, are proposed. It is shown that the leximin social welfare ordering can be expressed in terms of a ranking of distributions on the sole basis of their size, measured by the mean, and the degree of inequality, measured according to these inequality concepts. Leximin thus exhibits extreme bottom-sensitivity. This property does not withstand that leximin prefers a larger size of the cake at the cost of higher inequality in a number of cases. These trade-offs between size and equality are characterised in terms of degrees of dominance of the lower parts of the ordinary and absolute Lorenz curves that are accepted by leximin for a given increase in the mean.     

Migration to European Countries: A Structural Explanation of Patterns, 1980–20041

Various theoretical approaches have provided us with insights to explain the pattern of migration flows. Economic theory considers migration to be a reaction to labor market and economic incentives. Cultural theories predict that migration flows will occur according to a center‐periphery pattern, while social network analysis assumes that migrants follow already established migration networks. We test these three approaches simultaneously, using OECD and Eurostat data on the migrant inflow into the European countries between 1980 and 2004. The analysis demonstrates that migration flows react to economic incentives, mainly with regard to the labor market, but also to cultural and colonial linkages. There is no indication that the importance of the colonial past is declining over time. The response of migration patterns to shortages in the labor market is shown to be highly efficient, while the analysis shows that immigrants are not attracted by high levels of social expenditure.     

In Search of the Sources of Psychologically Controlling Parenting: The Role of Parental Separation Anxiety and Parental Maladaptive Perfectionism

This study investigated the role of two dimensions of parental separation anxiety—Anxiety about Adolescent Distancing (AAD) and Comfort with Secure Base Role (CSBR)—and parental maladaptive perfectionism in the prediction of psychologically controlling parenting. In a sample of middle adolescents and their parents (N=677), it was found that parents' AAD scores and maladaptive perfectionism were positively related to psychological control, whereas parents' CSBR scores were negatively related to psychological control. Further, psychological control served as an intervening variable in the links between parent characteristics and adolescent well‐being. These findings suggest that two qualitatively different types of psychological control may exist: one originating from parents' separation anxiety and another originating from parents' maladaptive perfectionist standards.     

COLLUSION IN PROCUREMENT AUCTIONS: AN EXPERIMENTAL EXAMINATION

Experimental methods are used to examine the existence and detectability of collusion in environments that exhibit critical parallels to procurement auctions. We find that given the opportunity sellers often raise prices considerably. Moreover, noncollusive Nash equilibrium predictions are insufficient to dismiss "suspicious" behavior as innocuous: in an environment where identical prices are predicted in a noncollusive Nash equilibrium, common prices are observed only when sellers communicate. In a second environment designed to parallel construction procurement contracting, market rotations are observed both with and without collusion, but collusion can often be detected from the pattern of losing bids.     

On the effect of the number of quadrature points in a logistic random effects model: an example

Although generalized linear mixed models are recognized to be of major practical importance, it is also known that they can be computationally demanding. The problem is the evaluation of the integral in calculating the marginalized likelihood. The straightforward method is based on the Gauss–Hermite technique, based on Gaussian quadrature points. Another approach is provided by the class of penalized quasi-likelihood methods. It is commonly believed that the Gauss–Hermite method works relatively well in simple situations but fails in more complicated structures. However, we present here a strikingly simple example of a logistic random-intercepts model in the context of a longitudinal clinical trial where the method gives valid results only for a high number of quadrature points ( Q ). As a consequence, this result warns the practitioner to examine routinely the dependence of the results on Q . The adaptive Gaussian quadrature, as implemented in the new SAS procedure NLMIXED, offered the solution to our problem. However, even the adaptive version of Gaussian quadrature needs careful handling to ensure convergence.