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991.
The argument in this paper rests on the assumption that the prime objective of any corporate activity must in some way be related to a profitability goal, however this may be measured, however this may be defined, and however this may be constrained by the relevance of a times-cale.
The paper makes some comments on the selection of a corporate objective or goal but mainly it considers the direct contribution that financial management can make to achievement of this goal. It distinguishes this from the accounting rôle which is more appropriately concerned with measuring and monitoring progress towards the goal. 相似文献
992.
Two-year chronic bioassays were conducted by using B6C3F1 female mice fed several concentrations of two different mixtures of coal tars from manufactured gas waste sites or benzo(a)pyrene (BaP). The purpose of the study was to obtain estimates of cancer potency of coal tar mixtures, by using conventional regulatory methods, for use in manufactured gas waste site remediation. A secondary purpose was to investigate the validity of using the concentration of a single potent carcinogen, in this case benzo(a)pyrene, to estimate the relative risk for a coal tar mixture. The study has shown that BaP dominates the cancer risk when its concentration is greater than 6,300 ppm in the coal tar mixture. In this case the most sensitive tissue site is the forestomach. Using low-dose linear extrapolation, the lifetime cancer risk for humans is estimated to be: Risk < 1.03 x 10(-4) (ppm coal tar in total diet) + 240 x 10(-4) (ppm BaP in total diet), based on forestomach tumors. If the BaP concentration in the coal tar mixture is less than 6,300 ppm, the more likely case, then lung tumors provide the largest estimated upper limit of risk, Risk < 2.55 x 10(-4) (ppm coal tar in total diet), with no contribution of BaP to lung tumors. The upper limit of the cancer potency (slope factor) for lifetime oral exposure to benzo(a)pyrene is 1.2 x 10(-3) per microgram per kg body weight per day from this Good Laboratory Practice (GLP) study compared with the current value of 7.3 x 10(-3) per microgram per kg body weight per day listed in the U.S. EPA Integrated Risk Information System. 相似文献
993.
Abstract Objective: This study aimed to understand the gaps in college students' knowledge regarding sexual health information. Participants: A sample of 242 participants enrolled in an introductory college course participated in this study in the Fall 2009 semester. Methods: Students participated in 1 of 2 brief interventions and wrote a response paper about their experience. The papers were analyzed using conventional content analysis for information that was new to participants by looking for key words that suggested learning took place. Results: The findings indicated that the majority of participants learned new information. Most learning occurred regarding sexually transmitted infections (ie, types, symptoms, prevalence, treatment, testing) and correct condom use. There were also demographic differences regarding reported new information. Conclusions: Findings can be used to develop future sex education programs for college students by providing college educators with an understanding of where students lack knowledge of sexual health. 相似文献
994.
Data envelopment analysis (DEA) and free disposal hull (FDH) estimators are widely used to estimate efficiency of production. Practitioners use DEA estimators far more frequently than FDH estimators, implicitly assuming that production sets are convex. Moreover, use of the constant returns to scale (CRS) version of the DEA estimator requires an assumption of CRS. Although bootstrap methods have been developed for making inference about the efficiencies of individual units, until now no methods exist for making consistent inference about differences in mean efficiency across groups of producers or for testing hypotheses about model structure such as returns to scale or convexity of the production set. We use central limit theorem results from our previous work to develop additional theoretical results permitting consistent tests of model structure and provide Monte Carlo evidence on the performance of the tests in terms of size and power. In addition, the variable returns to scale version of the DEA estimator is proved to attain the faster convergence rate of the CRS-DEA estimator under CRS. Using a sample of U.S. commercial banks, we test and reject convexity of the production set, calling into question results from numerous banking studies that have imposed convexity assumptions. Supplementary materials for this article are available online. 相似文献
995.
Christine W. Lai 《Journal of Family and Economic Issues》2006,27(4):601-625
This empirical study evaluates the magnitude of efficiency losses of household portfolio choices in self-directed pension
accounts (SDAs). It uses data from the Survey of Consumer Finances (SCF). The determinants of the magnitude of efficiency
losses across household investors are investigated in detail. The findings of this study lend empirical support to the belief
that the magnitude of efficiency losses for household investors differs with the different demographic characteristics and
investment propensities. In particular, household investors with long-investment horizons, with more autonomy of choices in
their SDAs, or with the tendency to select high levels of portfolio risk in SDAs are more vulnerable to efficiency losses.
Factors to predict the levels of portfolio risk maintained by household investors in their SDAs are also explored. 相似文献
996.
The issue of cultural diversity presents clinicians with both delemmas and opportunities. To deal with such a challenge, I have proposed a constructivist approach to the help-seeking process of clients from diverse ethnoracial backgrounds. A model of clients' help-seeking processes provides a useful and systematic frame for clinicians to understand clients' construction of their problem situations and possible solutions. It provides a useful key for clinicians non-presumptuously to understand clients' subjective experiences, and to enhance clients' ability to resolve problems. 相似文献
997.
Alan W. Rogers 《Journal of Rural Studies》1987,3(4)
Within the last decade or so, there has developed an increased concern for the welfare of rural communities and for individuals within such communities. At the same time there has emerged a parallel concern for environmental matters, concerned with conservation of species and habitat and the protection of cherished landscapes and amenities. Both sectors of rural concern have been characterised by debate about the means of delivery of policies and programmes in their respective areas and, in particular, about the balance between state action and the activities of the private sector. A common thread running through such debates has been the role of what is loosely called the ‘voluntary sector’, that is the complicated mix of individuals and organisations, local and national, which involve themselves in effort, not for direct payment nor as a routine of work, but because of feelings of commitment, belief and ideology.This paper is concerned with just one aspect of this sector — that which involves social and community aspects of the lives of rural dwellers in the English countryside. Despite this restricted field, there is an attempt to see things within a broader socio-political context, such that rural voluntarism and rural self-help can be assessed not only against a wider picture of volunteering generally but also placed within a political framework, both national and local. Voluntarism and self-help cannot exist independently of the world around them, yet the very process of facing up to the wider political realities creates problems of accountability and control to the extent that some would dismiss the voluntary sector as ineffective at best or the tool of vested interests at worst. 相似文献
998.
Carlton Cornett M.S.W. 《Child and Adolescent Social Work Journal》1985,2(2):83-92
Child physical abuse is a problem that moves from generation to generation. As yet, there has been no adequate theoretical conceptualization for this phenomenon. This article examines the multigenerational dimension of child abuse from the developmental perspective of psychoanalytic self-psychology. The research data available on the role of empathy in child abuse is integrated into the discussion and applied to the empirical basis of the self-psychology paradigm. Finally, the use of empathy in this theoretical model is applied to a discussion of intervention strategies in a number of treatment modalities. 相似文献
999.
1000.
ABSTRACT The distribution of the cross-correlations of squared residuals from Box-Jenkins models is considered in very general conditions, and the asymptotic distribution is derived. A test for a lagged relationship in volatility for economic time series under instantaneous causality is proposed, and its empirical behaviour is studied. An example involving the international stock market's volatility is studied, and an interesting result is observed. 相似文献