436 research outputs found
Sport and recreation activity patterns of 12-year-old learners at a city private primary school
Published ArticleThe new millennium brought about many changes, including changes in the physical activity patterns of children. Children are labelled as the "screen generation". Owing to the wide exposure to computers, television, play stations and cellphones, children tend to lead more sedentary lifestyles as their age increases. A survey was done at a city private primary school to determine the physical activity patterns of the Grade 6 (12 year old) learners (N=63, 33 boys and 30 girls). A self-constructed questionnaire, based on the activities the school offers and on the extramural activities the learners participate in, was used to measure the learners' physical activity patterns and to obtain data about their reasons and key motivators for participation. The responses show that the same group of learners participates in almost all the activities offered. The main problem clearly concerned learners who were uninvolved in all physical activities. Schools were identified as the key element to promote physical activity among learners (Vidyya, 2002:4; Aarnio, 2003:27). The activities must be positive and enjoyable to keep learners motivated and interested in future participation
On a new class of tests for the Pareto distribution using Fourier methods
We propose new classes of tests for the Pareto type I distribution using the
empirical characteristic function. These tests are and statistics based
on a characterisation of the Pareto distribution involving the distribution of
the sample minimum. In addition to deriving simple computational forms for the
proposed test statistics, we prove consistency against a wide range of fixed
alternatives. A Monte Carlo study is included in which the newly proposed tests
are shown to produce high powers. These powers include results relating to
fixed alternatives as well as local powers against mixture distributions. The
use of the proposed tests is illustrated using an observed data set
Evolution, appearance, and occupational success
Visual characteristics, including facial appearance, are thought to play an important role in a variety of judgments and decisions that have real occupational outcomes in many settings. Indeed, there is growing evidence suggesting that appearance influences hiring decisions and even election results. For example, attractive individuals are more likely to be hired, taller men earn more, and the facial appearance of candidates has been linked to real election outcomes. In this article, we review evidence linking physical appearance to occupational success and evaluate the hypothesis that appearance based biases are consistent with predictions based on evolutionary theories of coalition formation and leadership choice. We discuss why appearance based effects are so pervasive, addressing ideas about a "kernel of truth" in attributions and about coalitional psychology. We additionally highlight that appearance may be differently related to success at work according to the types of job or task involved. For example, leaders may be chosen because the characteristics they possess are seen as best suited to lead in particular situations. During a time of war, a dominant-appearing leader may inspire confidence and intimidate enemies while during peace-time, when negotiation and diplomacy are needed, interpersonal skills may outweigh the value of a dominant leader. In line with these ideas, masculine-faced leaders are favored in war-time scenarios while feminine-faced leaders are favored in peace-time scenarios. We suggest that such environment or task specific competencies may be prevalent during selection processes, whereby individuals whose appearance best matches perceived task competences are most likely selected, and propose the general term "task-congruent selection" to describe these effects. Overall, our review highlights how potentially adaptive biases could influence choices in the work place. With respect to certain biases, understanding their origin and current prevalence is important in order to potentially reduce discrimination in the work place
Cerebral palsy and its medicolegal implications in low-resource settings – the need to establish causality and revise criteria to implicate intrapartum hypoxia : a narrative review
The objective of this study was to establish scientific causality and to devise criteria to implicate intrapartum hypoxia in cerebral palsy (CP)
in low-resource settings, where there is potential for an increase in damaging medicolegal claims against obstetric caregivers, as is currently
the situation in South Africa. For the purposes of this narrative review, an extensive literature search was performed, including any research
articles, randomised controlled trials, observational studies, case reports or expert or consensus statements pertaining to CP in low-resource
settings, medicolegal implications, causality, and criteria implicating intrapartum hypoxia. In terms of causation, there are differences
between high-income countries (HICs) and low-resource settings. While intrapartum hypoxia accounts for 10 - 14% of CP in HICs, the
figure is higher in low-resource settings (20 - 46%), indicating a need for improved intrapartum care. Criteria implicating intrapartum
hypoxia presented for HICs may not apply to low-resource settings, as cord blood pH testing, neonatal brain magnetic resonance imaging
(MRI) and placental histology are frequently not available, compounded by incomplete clinical notes and missing cardiotocography
tracings. Revised criteria in an algorithm for low-resource settings to implicate intrapartum hypoxia in neonatal encephalopathy (NE)/
CP are presented. The algorithm relies first on specialist neurological assessment of the child, determination of the occurrence of neonatal
encephalopathy (by documented or verbal accounts) and findings on childhood MRI, and second on evidence of antepartum and
intrapartum contributors to the apparent hypoxia-related CP. The review explores differences between low-resource settings and HICs in
trying to establish causation in NE/CP and presents a revised scientific approach to causality in the context of low-resource settings for
reaching appropriate legal judgments.https://samajournals.co.za/index.php/samj/indexam2024Obstetrics and GynaecologyPaediatrics and Child HealthSDG-03:Good heatlh and well-bein
Gene flow and population structure of a solitary top carnivore in a human-dominated landscape
While African leopard populations are considered to be continuous as demonstrated by their high genetic variation, the southernmost leopard population exists in the Eastern and Western Cape, South Africa, where anthropogenic activities may be affecting this population's structure. Little is known about the elusive, last free-roaming top predator in the region and this study is the first to report on leopard population structuring using nuclear DNA. By analyzing 14 microsatellite markers from 40 leopard tissue samples, we aimed to understand the populations' structure, genetic distance, and gene flow (Nm). Our results, based on spatially explicit analysis with Bayesian methods, indicate that leopards in the region exist in a fragmented population structure with lower than expected genetic diversity. Three population groups were identified, between which low to moderate levels of gene flow were observed (Nm 0.5 to 3.6). One subpopulation exhibited low genetic differentiation, suggesting a continuous population structure, while the remaining two appear to be less connected, with low emigration and immigration between these populations. Therefore, genetic barriers are present between the subpopulations, and while leopards in the study region may function as a metapopulation, anthropogenic activities threaten to decrease habitat and movement further. Our results indicate that the leopard population may become isolated within a few generations and suggest that management actions should aim to increase habitat connectivity and reduce human-carnivore conflict. Understanding genetic diversity and connectivity of populations has important conservation implications that can highlight management of priority populations to reverse the effects of human-caused extinctions.Carnegie Corporation of New York to the Global Change and Sustainability
Research Institute at the University of the Witwatersrand. ABAX Foundation, Henry and Iris Englund Foundation, National Lotteries Distribution Trust Fund, Mones Michaels Trust, Arne Hanson, and Deutsche Bank South Africa Foundation.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)2045-7758hb201
Female economic dependence and the morality of promiscuity
This article is made available through the Brunel Open Access Publishing Fund. Copyright @ The Author(s) 2014.In environments in which female economic dependence on a male mate is higher, male parental investment is more essential. In such environments, therefore, both sexes should value paternity certainty more and thus object more to promiscuity (because promiscuity undermines paternity certainty). We tested this theory of anti-promiscuity morality in two studies (N = 656 and N = 4,626) using U.S. samples. In both, we examined whether opposition to promiscuity was higher among people who perceived greater female economic dependence in their social network. In Study 2, we also tested whether economic indicators of female economic dependence (e.g., female income, welfare availability) predicted anti-promiscuity morality at the state level. Results from both studies supported the proposed theory. At the individual level, perceived female economic dependence explained significant variance in anti-promiscuity morality, even after controlling for variance explained by age, sex, religiosity, political conservatism, and the anti-promiscuity views of geographical neighbors. At the state level, median female income was strongly negatively related to anti-promiscuity morality and this relationship was fully mediated by perceived female economic dependence. These results were consistent with the view that anti-promiscuity beliefs may function to promote paternity certainty in circumstances where male parental investment is particularly important
Exploring the components, asymmetry and distribution of relationship quality in wild Barbary macaques (Macaca sylvanus)
Social relationships between group members are a key feature of many animal societies. The quality of social relationships has been described by three main components: value, compatibility and security, based on the benefits, tenure and stability of social exchanges. We aimed to analyse whether this three component structure could be used to describe the quality of social relationships in wild Barbary macaques (Macaca sylvanus). Moreover, we examined whether relationship quality was affected by the sex, age and rank differences between social partners, and investigated the asymmetric nature of social relationships. We collected over 1,900 hours of focal data on seven behavioural variables measuring relationship quality,
and used principal component analysis to investigate how these variables clustered together. We found that relationship quality in wild Barbary macaques can be described by a three component structure that represents the value, compatibility and security of a relationship. Female-female dyads had more valuable relationships and same-age dyads more compatible relationships than any other dyad. Rank difference had no effect on the quality of a social relationship. Finally, we found a high degree of asymmetry in how members of a dyad exchange social behaviour. We argue that the asymmetry of social
relationships should be taken into account when exploring the pattern and function of social behaviour in animal societies
Zinc or Multiple Micronutrient Supplementation to Reduce Diarrhea and Respiratory Disease in South African Children: A Randomized Controlled Trial
Prophylactic zinc supplementation has been shown to reduce diarrhea and respiratory illness in children in many developing countries, but its efficacy in children in Africa is uncertain.To determine if zinc, or zinc plus multiple micronutrients, reduces diarrhea and respiratory disease prevalence.Randomized, double-blind, controlled trial.Rural community in South Africa.THREE COHORTS: 32 HIV-infected children; 154 HIV-uninfected children born to HIV-infected mothers; and 187 HIV-uninfected children born to HIV-uninfected mothers.Children received either 1250 IU of vitamin A; vitamin A and 10 mg of zinc; or vitamin A, zinc, vitamins B1, B2, B6, B12, C, D, E, and K and copper, iodine, iron, and niacin starting at 6 months and continuing to 24 months of age. Homes were visited weekly.Primary outcome was percentage of days of diarrhea per child by study arm within each of the three cohorts. Secondary outcomes were prevalence of upper respiratory symptoms and percentage of children who ever had pneumonia by maternal report, or confirmed by the field worker.Among HIV-uninfected children born to HIV-infected mothers, median percentage of days with diarrhea was 2.3% for 49 children allocated to vitamin A; 2.5% in 47 children allocated to receive vitamin A and zinc; and 2.2% for 46 children allocated to multiple micronutrients (P = 0.852). Among HIV-uninfected children born to HIV-uninfected mothers, median percentage of days of diarrhea was 2.4% in 56 children in the vitamin A group; 1.8% in 57 children in the vitamin A and zinc group; and 2.7% in 52 children in the multiple micronutrient group (P = 0.857). Only 32 HIV-infected children were enrolled, and there were no differences between treatment arms in the prevalence of diarrhea. The prevalence of upper respiratory symptoms or incidence of pneumonia did not differ by treatment arms in any of the cohorts.When compared with vitamin A alone, supplementation with zinc, or with zinc and multiple micronutrients, did not reduce diarrhea and respiratory morbidity in rural South African children.ClinicalTrials.gov NCT00156832
- …