A case–control study relating railroad worker mortality to diesel exhaust exposure using a threshold regression model

A case–control study of lung cancer mortality in U.S. railroad workers in jobs with and without diesel exhaust exposure is reanalyzed using a new threshold regression methodology. The study included 1256 workers who died of lung cancer and 2385 controls who died primarily of circulatory system diseases. Diesel exhaust exposure was assessed using railroad job history from the US Railroad Retirement Board and an industrial hygiene survey. Smoking habits were available from next-of-kin and potential asbestos exposure was assessed by job history review. The new analysis reassesses lung cancer mortality and examines circulatory system disease mortality. Jobs with regular exposure to diesel exhaust had a survival pattern characterized by an initial delay in mortality, followed by a rapid deterioration of health prior to death. The pattern is seen in subjects dying of lung cancer, circulatory system diseases, and other causes. The unique pattern is illustrated using a new type of Kaplan–Meier survival plot in which the time scale represents a measure of disease progression rather than calendar time. The disease progression scale accounts for a healthy-worker effect when describing the effects of cumulative exposures on mortality.     

The dilemmas of embodied symbolic representation: Regret in contemporary American tattoo narratives

Numerous scholars have argued that we are currently in a post “tattoo renaissance” era wherein the practice has increasingly become a legitimate art form accepted by the American middle class. In order to facilitate this cultural transition, tattooed people legitimize their own tattoos through various narratives that ascribe deep semantic meaning to their images and words. Pulling from twenty-two in-depth interviews with tattoo removal clinicians, tattoo artists, people who regret at least one of their current tattoos, and people who have had their tattoos removed or altered, this paper contributes to the literature on the meaning and significance of tattoos in the lives of 21st century Americans. In particular, we aim to showcase that, in the current cultural context, wherein people feel a need to justify their tattoos with a level of profound symbolic meaning, tattoo regret abounds in a form distinct from that of previous generations. Drawing from a post-structuralist framework which understands tattoos as symbols, we discuss tattoo narratives as pervasive normative expectations and explore how people face potential dilemmas when they lack them, as well as when they subscribe static and absolute meanings to the words and images depicted in their body art. These narratives, and accordingly the tattoos themselves, become problematic as a result of the inability of tattoos to function beyond their capacity as symbolic representations. When people cannot reconcile or transcend the dynamic and relative nature of their tattoos’ symbolic meanings, they feel regretful and sometimes opt for tattoo cover-ups or removals.     

精品课程建设中教材编写的创新思路探索——普通高等教育《土壤学》(“十五”国家级规划)教材的编写体会与实践

作者结合北京市精品课程建设,在组织编写普通高等教育“十五”国家级规划教材《土壤学》的过程中,认为首先应明确教材编写的指导思想,即在课程教材体系上有所创新,在课程教材内容上有所更新,在教学方法和手段上有所革新。同时在贯彻适用性和特色两个原则的基础上,进行了一些编写思路的探索和创新实践,这包括摸清读者底细、确定专业目标、把握课程内涵、了解市场需求,及正确处理好理论与应用、深度与广度、难度与易度、传统与创新、利教与利学、知识传授与技能培养的关系。通过以上步骤,保证了教材的先进性、系统性和特色,并实现了网络教学。     

The Effects of Perceived Barriers,Role Models,and Acculturation on the Career Self‐Efficacy and Career Consideration of Hispanic Women

This study used path analysis to examine the relationship between perceived barriers, acculturation, and role model influence on the career self‐efficacy and career considerations of a sample of Hispanic women. Two path models were examined. The male‐dominated model accounted for 15% of the variance, and the female‐dominated model accounted for 26% of the variance. No relationship was found between the variables of interest and male‐dominated career self‐efficacy and consideration. However, perceived barriers were related to female‐dominated career consideration and Anglo acculturation significantly contributed to female‐dominated career self‐efficacy. Results are discussed with regard to career practice and research with Hispanic women.     

Discovering Spatio-Temporal Models of the Spread of West Nile Virus

Emerging infectious diseases are characterized by complex interactions among disease agents, vectors, wildlife, humans, and the environment. Since the appearance of West Nile virus (WNV) in New York City in 1999, it has infected over 8,000 people in the United States, resulting in several hundred deaths in 46 contiguous states. The virus is transmitted by mosquitoes and maintained in various bird reservoir hosts. Its unexpected introduction, high morbidity, and rapid spread have left public health agencies facing severe time constraints in a theory-poor environment, dependent largely on observational data collected by independent survey efforts and much uncertainty. Current knowledge may be expressed as a priori constraints on models learned from data. Accordingly, we applied a Bayesian probabilistic relational approach to generate spatially and temporally linked models from heterogeneous data sources. Using data collected from multiple independent sources in Maryland, we discovered the integrated context in which infected birds are plausible indicators for positive mosquito pools and human cases for 2001 and 2002.     

A reverse sunk cost effect in risky decision making: Sometimes we have too much invested to gamble

The sunk cost effect refers to the empirical finding that people tend to let their decisions be influenced by costs made at an earlier time in such a way that they are more risk seeking than they would be had they not made these costs. This finding seems to be in conflict with economic theory which implies that only incremental costs and benefits should affect decisions. The effect is often explained in terms of prospect theory of (Kahneman, D., Tversky, A., 1979. Prospect theory: An analysis of decision under risk. Econometrica 47, 263–291), suggesting that sunk costs may induce a ‘loss frame,’ consequently causing risk seeking behavior. We argue that sunk costs may also result in risk aversion. In the present study we investigated the effect of time and effort investments (Behavioral Sunk Costs) on risky decision making in gain and loss situations. The results show that, in agreement with prospect theory, participants were more risk averse in gain situations than in loss situations. Moreover, incurring Behavioral Sunk Costs appeared to increase risk aversive choices, i.e., a reverse sunk cost effect. Furthermore, the results suggest that, in loss situations, Behavioral Sunk Costs mainly lead to risk aversive behavior if opting for the ‘safe’ alternative is not accompanied by an increased possibility to regret the decision.     

Use of incentives to motivate healthy behaviors among employees

We conducted an extensive literature search of both published and unpublished sources to assess the use and effectiveness of worksite interventions that offer financial and other incentives. Many companies are using financial incentives, either alone or in combination with other interventions, to motivate employees to adopt and maintain healthier lifestyles. These incentives include cash bonuses, paid vacation days, and health insurance rebates. Although more research is needed, the literature suggests that financial incentives, if properly implemented, may successfully promote behavioral change among employees. Eric A. Finkelstein Ph.D., M.H.A. currently conducts economic and health policy research at RTI International, teaches an undergraduate Health Economics course at Duke University, and is a member of RTI-UNC Center of Excellence in Health promotion Economics. He focuses on the economic causes and consequences of health behaviors, with a primary emphasis on behaviors related to obesity. He has published several peer-reviewed papers in this area. A recent publication entitled “National Medical Expenditures Attributable to Overweight and Obesity,” was published in Health Affairs and garnered national media attention, including a front-page story in USA Today, coverage in Time magazine and the Washington Post, and was reported in other radio, television, newspaper, and Internet outlets across the country. That paper is now routinely cited as a driving motivation to reduce obesity rates. Dr. Finkelstein currently leads several projects concerning the causes and consequences of health behaviors for the CDC and other public and private sector agencies, and frequently speaks at conferences concerning the economic impact of obesity and strategies for reducing this burden. Katherine M. Kosa, M.S. conducts economic and food and nutrition policy research at RTI International with a primary focus on consumer behavior research. She recently completed a study to examine the general public's attitude and support for obesity interventions recently introduced at the state and federal level. To inform labeling policy decisions for USDA and FDA, Ms. Kosa conducts focus groups and surveys to understand consumer attitudes, knowledge, and practices.     

HIV/AIDS and Cross-National Convergence in Life Expectancy

This article analyzes the effect of HIV/AIDS on the cross-national convergence in life expectancy as well as infant and child survival rates by comparing three scenarios. One is based on historical and future best-guess estimated values given the existence of the epidemic. The second scenario assumes that the effect of the epidemic is much worse than expected. The final scenario is based on hypothetical values derived from estimations where the mortality caused by the epidemic is removed. For life expectancy, convergence becomes stalled in the late 1980s (without weighting by country population size) or 1990s (with weighting). Convergence in infant and child survival rates does not become stalled, but slows down. These results are mainly attributable to the epidemic since all signs of stalled convergence or even divergence disappear in the “No AIDS scenario.” Given the existence of the epidemic, however, the reduced degree of inequality in life expectancy attained by 1985 is only expected to be achieved again by 2015 at the earliest. If the epidemic turns out much worse than expected, divergence could continue to 2050. No divergence is to be expected in infant and child survival rates in any of the scenarios.