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291.
292.
Although collaboration in child abuse investigations has been emphasized since 1974, barriers, including role conflicts and organizational differences, have often been reported. This study describes the process of collaboration based on the perceptions of investigators working with a Child Advocacy Center. Telephone interviews were conducted with 290 child protective service workers and law enforcement officers from 28 child advocacy centers in 20 different states. Respondents identified barriers to the process of collaboration such as conflicts over case control and facilitators including co-housing and cross-training. Conditions that should contribute to successful collaboration are discussed. 相似文献
293.
Goulet ED Mélançon MO Dionne IJ Aubertin-Leheudre M Aubertin Leheudre M 《Journal of aging and physical activity》2005,13(3):314-326
It is unclear whether long-term aerobic (AT) or resistance (RT) training can improve insulin sensitivity (IS) beyond the residual effect of the last training bout in older women (54-78 years). Therefore, a group of nonobese, healthy older women underwent 6 months of AT (n = 8) or RT (n = 10), and the authors measured IS 4 days after the last training bouts using the hyperinsulinemic-euglycemic clamp technique. Women trained 3 days/week. AT consisted of 25- to 60-min sessions of walking/jogging at 60-95% of maximal heart rate. RT consisted of three sets of nine exercises repeated 10 times at 80% of 1 repetition maximum. AT decreased fat mass, whereas both AT and RT increased fat-free mass. Neither training program, however, improved absolute or relative rates of glucose disposal. The authors therefore concluded that nonobese, healthy older women should perform AT or RT on a daily basis in order to improve IS and maintain the improvement. 相似文献
294.
295.
296.
In repeated sampling enquiries application of method of successive sampling with partial replacement of units is advantageous. In this paper use of successive sampling technique when the sampling design is multi-stage has been studied. Estimates of population mean and its variance have been obtained (a) on the second occasion, and (b) on the h-th occasion under two systems of replacement, namely (i) by retaining only a fraction p of psu's along with their sample of ssu's, and (ii) by retaining all the psu's on the second occasion, but from each psu only a fraction p of the ssu's within them is retained. A cost function suitable to the design has been illustrated, with the help of data collected from a sample survey conducted by the Indian Council of Agricultural Research. 相似文献
297.
Zarate AO 《Demography》1967,4(1):363-373
Recent investigations indicate that fertility is not universally associated with urbanization and economic development in the manner predicted by the theory of the demographic transition. It is possible, however, that these investigations only partially test the theory, for the degree of industrialization in urbanareas is rarely taken into account. Two hypotheses are tested based upon Mexican census and vital registration data for 1940-60: (a) urban fertility is inversely related to the proportion of the urban population employed in the secondary sector of the economy and (b) changes in urban fertility are inversely related to changes in the proportion of the urban population employed in the secondary sector of the economy.At each census date from 1940 to 1960, the association between urban fertility (age-standardized child-woman ratio adjusted for infant mortality) and the percent in the secondary sector is low and positive. In 1960, however, the association is negative (suggesting a possible change in the direction of the association), but city growth rates and the proportion of females married are more closely related to fertility than percent in the secondary sector. Hypothesis a, then, receives little support from the data.Much the same is true of hypothesis b. The association between changes in urban fertility and changes in the percent in the secondary sector is positive. Moreover, city growth rates and changes in the proportion literate explain more of the variation in fertility change than does the percent in the secondary sector.In addition, over-all fertility has risen since 1940, and this rise is pronounced in large urban areas. It is suggested that among certain segments of Mexican society, the response to economic development has been an increase rather than a reduction in fertility. It is further suggested that if city growth is indicative of rural-urban migration, the presence of large numbers of rural migrants in urbanareas may help to explain the decreasing size of the urban-rural fertility differential in Mexico.If this interpretation is correct, the theory of the demographic transition is in need of further modification, specification, and verification. 相似文献
298.
William O’Hare 《Demography》1976,13(3):369-379
A new method of making population estimates is introduced and contrasted to the standard ratio-correlation method. The new method, called the “difference-correlation method,” produced population estimates for the counties of Michigan which had a smaller mean percentage error than estimates produced by the ratio-correlation method. The differences of proportions which are used in the difference-correlation method will always have means of zero, while the ratios used in the ratio-correlation method have means which vary. Higher intercorrelations among the variables and increased temporal stability of the intercorrelations are two advantages of using differences rather than ratios. 相似文献
299.
Potenza MN Steinberg MA Wu R Rounsaville BJ O'malley SS 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2006,22(2):241-254
Background Few investigations have characterized groups of older adults with gambling problems, and published reports are currently limited by small samples of older adult problem gamblers. Gambling helplines represent a widespread mechanism for assisting problem gamblers to move into treatment settings. Given data from older adult problem gamblers in treatment, we hypothesized that older as compared with younger adult problem gamblers calling a gambling helpline would be less likely to report gambling-related problems.Design and methods Logistic regression analyses were performed on data obtained from January 1, 2000 to December 31, 2001, inclusive, from callers with gambling problems (N = 1,084) contacting the Connecticut Council on Problem Gambling Helpline.Results Of the 1,018 phone calls used in the logistic regression analyses, 168 (16.5%) were from older adults and 850 (83.5%) from younger adults. Age-related differences were observed in demographic features, types and patterns of gambling reported as problematic, gambling-related problems and psychiatric symptoms, substance use problems, patterns of indebtedness, and family histories of addictive disorders. Older as compared with younger adult problem gamblers were more likely to report having lower incomes, longer durations of gambling, fewer types of problematic gambling, and problems with casino slot machine gambling and less likely to report gambling-related anxiety, family problems, illegal behaviors and arrests, drug problems, indebtedness to bookies or acquaintances, family histories of drug abuse, and problems with casino table gambling.Conclusions Older as compared with younger adult problem gamblers calling a gambling helpline differ on many clinically relevant features. The findings suggest the need for improved and unique prevention and treatment strategies for older adults with gambling problems. 相似文献
300.
Gyula O. H. Katona 《Journal of statistical planning and inference》2002,100(2):319-336
One unknown element of an n-element set is sought by asking if it is contained in given subsets. It is supposed that the question sets are of size at most k and all the questions are decided in advance, the choice of the next question cannot depend on previous answers. At most l of the answers can be incorrect. The minimum number of such questions is determined when the order of magnitude of k is n with <1. The problem can be formulated as determination of the maximum sized l-error-correcting code (of length n) in which the number of ones in a given position is at most k. 相似文献