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951.
Summary Dispersal, immigration and emigration rates, horizontal and vertical survivorship and absolute population size were estimated
for micropopulations ofAn. culicifacies, An. stephensi andAn. subpictus at a series of cattle sheds in rural Punjab Province, Pakistan, during November 1979 and May 1980 using capture-mark-release-recapture
and dissection methods. Dispersal was temperature-related, with populations more vagile during May. Mean dispersal distance
per individual was low for all species. More than 70% of all recaptures were taken at the point of release and the longest
detected flight was 1250 meters.
Horizontal survivorship was greater during November and was always less than vertical survivorship calculated from dissection
agegrading data. Survivorship during the nulliparous period was greater than survivorship throughout total life, indicating
the survivorship curve may be slightly sigmoid. Daily population sizes of endemic and immigrating females and males were calculated
usingBailey's (1952) modification of the Lincoln Index, with the daily captures adjusted for immigration which was highest in May. Daily
additions to the indoor resting population exclusive of immigrants were estimated using the method ofManly andParr (1968). The relationship of the present findings to malaria transmission and genetic control were discussed. 相似文献
952.
Keyfitz N 《Population studies》1966,19(3):281-295
Abstract Conventions exist for carrying out the arithmetic of population projection, finding the intrinsic rate of natural increase, and other demographic calculations. These are good approximations only for populations which are stationary or increasing very slowly. For rapidly increasing populations, which are presently the subject of much study, they can be readily improved. The improved formulae take account of the way in which the increase shifts the distribution of population within the five-year age group. A number of examples are given of the derivation of corrections to existing formulae. While the corrections are smaller than the error of the data available for most countries, such formulae are worth introducing in anticipation of better data. They in no way depend on machine computation, but the computer makes them especially easy to apply. 相似文献
953.
954.
The authors sought to determine whether a greater academic incentive would improve the effectiveness and student adherence to a 12-week voluntary exercise program designed to decrease students' percentage of body fat. They randomly assigned 210 students to 1 of 2 groups with different academic reward structures. The group with the greater reward structure showed better exercise adherence and lost more body fat than those without the additional incentive. These findings suggest that an academic incentive can increase overall student adherence to a voluntary exercise program and can boost the effectiveness of the program in a university environment. The findings also have potential implications for on-campus promotion of physical activity. 相似文献
955.
Administrative positions within higher education have been very homogeneous, reflecting an institutional culture in which males prevail. In an attempt to encourage women to consider alternatives in administrative positions, internship programs were developed to provide women with opportunities and a mechanism for career advancement. The purpose of this case study was to examine what women did as a result of participating in such an administrative internship program over a ten year time period at a comprehensive university. Interview data yielded consistent results that support existing literature about women in higher education. Trends were identified and recommendations suggested for encouraging more diversity within administrative positions in higher educational institutions. The findings of this study confirm the need for mentoring relationships for women in administrative positions. 相似文献
956.
Shah KR Eisen SA Xian H Potenza MN 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2005,21(2):179-203
Twin studies represent an important and powerful approach to estimating the relative contributions of environmental and genetic factors to the expression of psychiatric illnesses. In this article, we first explain the rationale for using large populations of monozygotic and dizygotic twin pairs to estimate genetic and environmental contributions to a disorder and the statistical modeling associated with this approach. We then review results from studies of the Vietnam Era Twin Registry that use this methodology to examine the etiology of pathological gambling (PG) behaviors. The results provide strong evidence for genetic contributions to the development of PG in men and set the foundation for future studies aimed at identifying the manner in which specific genes and environmental factors individually and in conjunction contribute to PG. 相似文献
957.
Social representations of diversity: multi/intercultural education in a South African urban school 1
Nicole Carignan Roland G. Pourdavood Lonnie C. King Nosisi Feza 《Intercultural Education》2005,16(4):381-393
The story of School X started in South Africa in 1875. At that time, the school was built for white children only. More than hundred years later, the 1994 elections demarcated the end of the apartheid era and the school enrolled black Xhosa‐speaking children for the first time. As a result, in 2004, 90% of the students were black Xhosa‐speaking. The theoretical perspectives of our study are based on notions of multicultural and intercultural education, and of diversity. Our study is embedded in a socio‐constructivist inquiry paradigm. Using questionnaires and interviews, we aimed to understand the social representations regarding diversity of a principal, a teacher, seven students and four parents in a K‐7 open school. We examined diversity of values, cultures, religions, languages, attitudes, beliefs, behaviors, etc. regarding a multi/intercultural perspective in education. We attempted to discern what the participants’ understandings of diversity were, how they identified diversity, and why they justified their practices and actions with respect to diversity.
The song can only be beautiful if we all play the same tune. (Esmé Goosen, Multimedia, 2004) This is the title of a painting that is part of an exhibition in Nelson Mandela Metropolitan Museum of Art, Port Elizabeth, South Africa 相似文献
958.
The aim of this study was to examine the interaction between aging and 10 years of racing in endurance runners. Race-time data from 194 runners who had completed 10 consecutive 56-km ultramarathons were obtained. The runners were either 20.5 +/- 0.7, 30.0 +/- 1.0, 39.9 +/- 0.9, or 49.4 +/- 1.0 years old at their first race. Each runner's race speed was determined for each race over the 10 years. Data were analyzed using repeated-measures ANOVA, one-way ANOVA, and independent t tests and showed that performance improved and declined at greater rates for younger runners; younger runners had a greater capacity for improvement than older runners; approximately 4 years were required to reach peak racing speed, regardless of age; it was not possible to compete at peak speed for more than a few years; and the combined effects of 10 years of aging and racing neither improve nor worsen net performance. In conclusion, these data suggest that although these runners showed similar patterns of change in race speed over a 10-year period, the extent of change in performance was greater in younger than in older runners. 相似文献
959.
Ann?E.?BiddlecomEmail author William?G.?Axinn Jennifer?S.?Barber 《Population and environment》2005,26(3):583-621
This study investigates the relationship between environmental degradation and men and womens family size preferences and subsequent reproductive behaviors in Nepal. We draw on unique environmental data at the local level, household and individual-level survey data and individuals reproductive behavior over a 3 year time period in Western Chitwan Valley, Nepal. Results from Ordinary Least Squares (OLS) and logistic regression models show that poorer environmental quality and greater reliance on publicly owned natural resources are associated with higher family size preferences and higher rates of pregnancy. The analyses provide support for the vicious circle argument that environmental degradation can lead to rising population growth via positive effects on fertility. As environmental conditions decline and when households rely on public lands for natural resources, men and women desire larger family sizes and women are more likely to get pregnant in the near future. 相似文献
960.
The sample survey, involving the use of specially developed questionnaires and instruments, is an important source of data regarding individual experiences and social-psychological characteristics for use in social indicator research. Variable errors of measurement are often given only cursory attention in presentations of survey sampling and social indicator theory and in the analysis of such data. These errors may, however, result in reduced precision of estimates and may affect statistical inferences drawn from the data. Some procedures for assessing the extent of variable measurement error are described and examples of their use in evaluating a survey instrument and data collected are discussed. 相似文献