Carleton University

About: Carleton University is a education organization based out in Ottawa, Ontario, Canada. It is known for research contribution in the topics: Population & Context (language use). The organization has 15852 authors who have published 39650 publications receiving 1106610 citations.

Body weight dissatisfaction and communication with parents among adolescents in 24 countries: international cross-sectional survey.

Abstract: Parents have significant influence on behaviors and perceptions surrounding eating, body image and weight in adolescents. The aim of this study was to examine the prevalence of body weight dissatisfaction, difficulty in communication with the parents and the relationship between communication with parents and adolescents' dissatisfaction with their body weight (dieting or perceived need to diet). Survey data were collected from adolescents in 24 countries and regions in Europe, Canada, and the USA who participated in the cross-sectional 2001/2002 Health Behaviour of School-Aged Children (HBSC) study. The association between communication with parents and body weight dissatisfaction was examined using binary logistic regression analysis. Body weight dissatisfaction was highly prevalent and more common among girls than boys, among overweight than non-overweight, and among older adolescents than younger adolescents. Difficulty in talking to father was more common than difficulty in talking to mother in all countries and it was greater among girls than among boys and increased with age. Difficulties in talking to father were associated with weight dissatisfaction among both boys and girls in most countries. Difficulties in talking to mother were rarely associated with body weight dissatisfaction among boys while among girls this association was found in most countries. The findings suggest that enhanced parent communication might contribute in most countries to less body dissatisfaction in girls and better communication with the father can help avoiding body weight dissatisfaction in boys. Professionals working with adolescents and their families should help adolescents to have a healthy weight and positive body image and promote effective parent – adolescent communication.

Emerging Country Cross-Border Acquisitions: Characteristics, Acquirer Returns and Cross-Sectional Determinants

Abstract: What are the important characteristics of cross-border acquisitions (CBAs) by firms from emerging countries and do these acquisitions create market value for the acquirers? Using a unique and a manually collected dataset, we identify 698 CBAs made by emerging country firms during the period January 1991 through December 2008. Targets tend to be small (by U.S. transaction value measures) – the median ranging between $10 million to $40 million (in 2008 dollars). However, from 2000 to 2008, 24 acquisitions were worth more than a billion dollars each. Emerging country acquirers experience a positive and a significant market response of 1.09% on the announcement day. Additionally, in the cross-section, acquirer returns are positively correlated with (better) corporate governance measures in the target country. The positive announcement return and the cross-sectional relation between these returns and governance measures are consistent with Martynova and Renneboog’s (2008) and Khanna and Palepu’s (2004) bootstrapping hypothesis: The acquirer voluntarily bootstraps itself to the higher governance standards of the target – resulting in a positive valuation impact for the acquirer.

The effects of early postnatal stimulation on Morris water-maze acquisition in adult mice : genetic and maternal factors

Abstract: Following stressor exposure BALB/cByJ mice exhibit hypersecretion of corticosterone and marked brain catecholamine alterations. In addition, mice of this strain exhibit impairments of performance in a Morris water-maze, which may be exacerbated by footshock application. In the present investigation it was demonstrated that early-life handling of mouse pups (coupled with brief separation periods from the dam over the course of 21 days postpartum) reduced the learning impairments seen when mice were tested in the Morris water-maze at 120 days of age and also prevented stress-induced disturbances in this task. Likewise, cross-fostering BALB/cByJ mice with a C57BL/6ByJ dam prevented the performance deficits. In contrast, C57BL/6ByJ mice cross-fostered to a BALB/cByJ dam exhibited proficient performance. Thus, maternal factors may be important in determining the Morris water-maze disturbances, provided that this was applied on the BALB/cByJ genetic background. Stressor exposure exacerbated the performance disturbances in BALB/cByJ mice, while diazepam treatment disrupted Morris water-maze performance in both BALB/cByJ and C57BL/6ByJ mice. Paralleling the behavioral changes associated with handling, the stress-induced hypercorticosterone secretion characteristic of the BALB/cByJ mouse was attenuated by the early handling procedure. Stressor exposure also produced strain-dependent variations of NE and 5-HT, but these effects were not appreciably influenced by the handling procedure. These data are consistent with the proposition that performance disturbances of BALB/cByJ mice tested in the Morris water-maze task are associated with excessive hypothalamic-pituitary-adrenal reactivity. Moreover, it appears that the influence of early-life stimulation may interact with genetic factors in determining endocrine and behavioral stress responses.

Tax Systems in the World: An Empirical Investigation into the Importance of Tax Bases, Administration Costs, Scale and Political Regime

Abstract: We study the structure of taxation in a sample of 100 democratic and nondemocratic regimes over three time periods. The results provide strong support for several regularities in the world as a whole, specifically (1) scale effect: utilization of each tax source increases as the government expands, (2) base effect: tax systems rely more heavily on relatively larger tax bases, and (3) administrative cost effect: lower costs of administration lead to increased reliance on the corresponding revenue source. We also investigate the role of political regime and find that democracies rely substantially more on other income taxation, possibly because this tax source requires a higher degree of voluntary compliance.

Do Diradicals Behave like Radicals

Abstract: This review sets out to understand the reactivity of diradicals and how that may differ from monoradicals. In the first part of the review, we delineate the electronic structure of a diradical with its two degenerate or nearly degenerate molecular orbitals, occupied by two electrons. A classification of diradicals based on whether or not the two SOMOs can be located on different sites of the molecule is useful in determining the ground state spin. Important is a delocalized to localized orbital transformation that interchanges "closed-shell" to "open-shell" descriptions. The resulting duality is useful in understanding the dual reactivity of singlet diradicals. In the second part of the review, we examine, with a consistent level of theory, activation energies of prototypical radical reactions (dimerization, hydrogen abstraction, and addition to ethylene) for representative organic diradicals and diradicaloids in their two lowest spin states. Differences and similarities in reactivity of diradicals vs monoradicals, based on either a localized or delocalized view, whichever is suitable, are then discussed. The last part of this review begins with an extensive, comparative, and critical survey of available measures of diradical character and ends with an analysis of the consequences of diradical character for selected diradicaloids.