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991.
Communication about risks offers a voluntary approach to reducing exposure to pollutants. Its adequacy depends on its impact on behavior. Estimating those impacts first requires characterizing current activities and their associated risk levels, and then predicting the effectiveness of risk-reduction strategies. Characterizing the risks from chemical consumer products requires knowledge of both the physical and the behavioral processes that influence exposures. This article presents an integrated approach that combines consumer interviews, users' beliefs and behaviors, and quantitative exposure modeling. This model was demonstrated in the context of consumer exposure to a methylene chloride-based paint stripper, showing how it could be used to evaluate current levels of risk and predict the effectiveness of proposed voluntary risk-reduction strategies.  相似文献   
992.
Ethylene oxide is a gas produced in large quantities in the United States that is used primarily as a chemical intermediate in the production of ethylene glycol, propylene glycol, non-ionic surfactants, ethanolamines, glycol ethers, and other chemicals. It has been well established that ethylene oxide can induce cancer, genetic, reproductive and developmental, and acute health effects in animals. The U.S. Environmental Protection Agency is currently developing both a cancer potency factor and a reference concentration (RfC) for ethylene oxide. This study used the rich database on the reproductive and developmental effects of ethylene oxide to develop a probabilistic characterization of possible regulatory thresholds for ethylene oxide. This analysis was based on the standard regulatory approach for noncancer risk assessment, but involved several innovative elements, such as: (1) the use of advanced statistical methods to account for correlations in developmental outcomes among littermates and allow for simultaneous control of covariates (such as litter size); (2) the application of a probabilistic approach for characterizing the uncertainty in extrapolating the animal results to humans; and (3) the use of a quantitative approach to account for the variation in heterogeneity among the human population. This article presents several classes of results, including: (1) probabilistic characterizations of ED10s for two quantal reproductive outcomes-resorption and fetal death, (2) probabilistic characterizations of one developmental outcome-the dose expected to yield a 5% reduction in fetal (or pup) weight, (3) estimates of the RfCs that would result from using these values in the standard regulatory approach for noncancer risk assessment, and (4) a probabilistic characterization of the level of ethylene oxide exposure that would be expected to yield a 1/1,000 increase in the risk of reproductive or developmental outcomes in exposed human populations.  相似文献   
993.
Try to gain as much knowledge as possible about the culture, tactics, psychology and sensitivity of a hiring organization before you go on the job interview. Even small slights or seemingly harmless missteps can cost you the job.  相似文献   
994.
This article describes how the effectiveness of risk communication is determined by the interaction between emotional and informative elements. An experiment is described that examined the role of negative emotion in communication about CO2 risks. This experiment was based on the elaboration likelihood model and the related heuristic systematic model of attitude formation. The results indicated that inducing fear of CO2 risks leads to systematic processing of information about energy conservation as a risk-reducing strategy. In turn, this results in more favorable attitudes toward energy conservation if strong arguments are provided. Individual differences in concern seem to have similar effects.  相似文献   
995.
There exists a joint-cost allocation problem in the public sector, particularly highlighted by the cost-based national pricing of blood products in England, supposedly derived using volume-driven activity-based costing (ABC): an approach criticised by the implementation criteria propounded for ABC within the academic literature. In contrast, we believe that the contributions of quality-associated operations-based drivers, described within ABC, together with the net realisable value method, usually recommended as the optimal joint-cost allocation method, provide the beginnings of a solution. This paper sets out a methodological development from this platform that links allocation decisions with the issue of value. The bipolar nature of the model is based upon the combination of two types of allocation. One allocates joint costs according to the altered value of source material when competing non-joint alternative products exist. The other allocates joint costs according to product outcome values ascertained separately for the physical specification elements that comprise each of the range of joint products. The overall emphases are on academic context, model generalisation, the facilitation of cost-effective choices between joint products and non-joint alternatives, and possible future trends in the application of the method.  相似文献   
996.
Much leadership literature neglects its historical-contextual antecedents and as a result over-emphasizes zeitgeist, or tenor of the time's social forces. This neglect impedes leadership research by encouraging academic amnesia and promoting a strong feeling of research déjà vu among many researchers and practitioners. In this article, we develop a leadership historical-contextual superstructure consisting of evolutionary antecedents, paradigmatic antecedents, purpose and definitional antecedents, stakeholder antecedents, levels of analysis and temporal antecedents, and research dissemination antecedents. We use this superstructure to analyze current work in the increasingly important relational leadership research stream to illustrate how the superstructure's use can aid leadership researchers and practitioners in avoiding leadership déjà vu and academic amnesia and help build a more cumulative field.  相似文献   
997.
We investigate lifting, i.e., the process of taking a valid inequality for a polyhedron and extending it to a valid inequality in a higher dimensional space. Lifting is usually applied sequentially, that is, variables in a set are lifted one after the other. This may be computationally unattractive since it involves the solution of an optimization problem to compute a lifting coefficient for each variable. To relieve this computational burden, we study sequence independent lifting, which only involves the solution of one optimization problem. We show that if a certain lifting function is superadditive, then the lifting coefficients are independent of the lifting sequence. We introduce the idea of valid superadditive lifting functions to obtain good aproximations to maximum lifting. We apply these results to strengthen Balas' lifting theorem for cover inequalities and to produce lifted flow cover inequalities for a single node flow problem.  相似文献   
998.
Innovation is nowadays a fundamental determinant of value creation in business companies and economic growth. Therefore, the measurement of innovation has become a significant concern both for business companies and governments. Traditionally, attempts to measure innovation have adopted a macroeconomic approach, as they have been largely based on broad surveys. However, no attempt has been made to date in order to complement the information provided by such surveys with aggregated data obtained from the financial reports of individual companies. This paper analyses the conceptual and methodological problems underlying the measurement of business innovation by means of surveys and discusses the lack of ability of accounting standards to accurately reflect innovative activities in the financial statements of business firms.In the light of the evidence provided by the empirical studies published to date, we analyse the Spanish situation by reviewing innovation studies conducted by the National Institute of Statistics (INE), and assessing the relationship between the value relevance of accounting information and the firm's technological level. Our results suggest that both, micro- and macroeconomic approaches towards the measurement of innovation have significant shortcomings. Thus, a joint effort seems to be needed in order to overcome the methodological limitations affecting innovation studies based on surveys and those relying on financial accounting information. Despite their limitations, surveys provide a sound basis for the identification of trends, key factors and explanatory variables. On the other hand, financial statements could provide a sound basis for the measurement of innovation if they included more relevant information on the intangible determinants of the value of companies. This has obvious implications for the standard setting process.  相似文献   
999.
Genetic differences (polymorphisms) among members of a population are thought to influence susceptibility to various environmental exposures. In practice, however, this information is rarely incorporated into quantitative risk assessment and risk management. We describe an analytic framework for predicting the risk reduction and value-of-information (VOI) resulting from specific risk management applications of genetic biomarkers, and we apply the framework to the example of occupational chronic beryllium disease (CBD), an immune-mediated pulmonary granulomatous disease. One described Human Leukocyte Antigen gene variant, HLA-DP beta 1*0201, contains a substitution of glutamate for lysine at position 69 that appears to have high sensitivity (approximately 94%) but low specificity (approximately 70%) with respect to CBD among individuals occupationally exposed to respirable beryllium. The expected postintervention CBD prevalence rates for using the genetic variant (1) as a required job placement screen, (2) as a medical screen for semiannual in place of annual lymphocyte proliferation testing, or (3) as a voluntary job placement screen are 0.08%, 0.8%, and 0.6%, respectively, in a hypothetical cohort with 1% baseline CBD prevalence. VOI analysis is used to examine the reduction in total social cost, calculated as the net value of disease reduction and financial expenditures, expected for proposed CBD intervention programs based on the genetic susceptibility test. For the example cohort, the expected net VOI per beryllium worker for genetically based testing and intervention is $13,000, $1,800, and $5,100, respectively, based on a health valuation of $1.45 million per CBD case avoided. VOI results for alternative CBD evaluations are also presented. Despite large parameter uncertainty, probabilistic analysis predicts generally positive utility for each of the three evaluated programs when avoidance of a CBD case is valued at $1 million or higher. Although the utility of a proposed risk management program may be evaluated solely in terms of risk reduction and financial costs, decisions about genetic testing and program implementation must also consider serious social, legal, and ethical factors.  相似文献   
1000.
Those who don't "interview well" are not likely to receive the job offer, despite their qualifications. A job interview is actually a fierce competitive activity that offers only two grades: an A or F. By nature, physicians are competitive; they like to win. Infrequent interviewees are prone to making easily corrected mistakes, such as showing no enthusiasm or having poor eye contact. The key for interviewing success is preparation--doing research, developing a personal statement, and role-playing practice interviews. View the interview as a sales call whose bottom-line goal is to achieve an offer, or at least to let you leave with the option to return for future discussions.  相似文献   
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