The Special Historical Section of the Journal of American College Health

Abstract

Objective: To identify human papillomavirus (HPV) infection and HPV vaccine–related attitudes among college-aged women and the relationship between HPV vaccine uptake and subsequent sexual behaviors. Methods: PubMed, MEDLINE, CINAHL, and Google Scholar searches were performed from 2006, the date after the first HPV vaccine became available, to present. Results: Of the 13 studies identified, most were cross-sectional. College-aged women saw HPV infection as serious and had positive attitudes toward the HPV vaccine. Barriers (ie, cost, lack of insurance coverage) existed that prevented women from obtaining the vaccine and many women did not see themselves at risk for HPV. The vaccine uptake rate, although increasing, has been slow. Conclusion: College-aged women in the United States may need unbiased information about HPV and HPV vaccine. Studies that focus on risk perception and the relationship between knowledge, attitudes, vaccine uptake, and sexual behaviors are needed to inform interventions and public health programs.     

世界各国聚焦氢能源经济

氢是宇宙中最丰富的元素，地球上分布着大量的氢，其来源丰富。氧还是元素周期表中最轻的一个元素，与其他物质相比，具有较高的重量比能量。氢的燃烧产物是水，非常清洁，不会对环境造成污染。因此人们对氢能源的开发与利用也产生了极大的兴趣。     

Four tests of fit for the beta-binomial distribution

Tests based on the Anderson–Darling statistic, a third moment statistic and the classical Pearson–Fisher X ² statistic, along with its third-order component, are considered. A small critical value and power study are given. Some examples illustrate important applications.     

Second Quarter 1973 Survey of the Economic Outlook

The aim of the author is improvement of statistical practice. The author distinguishes between enumerative studies and analytic studies. An enumerative study has for its aim an estimate of the number of units of a frame that belong to a specified class. An analytic study has for its aim a basis for action on the cause-system or the process, in order to improve product of the future. A fair price to pay for an inventory is an example of an enumerative study. Tests of varieties of wheat, insecticides, drugs, manufacturing processes, are examples of analytic studies: the choice of variety or treatment will affect the future out-turn of wheat, future patients, future product. Techniques and methods of inference that are applicable to enumerative studies lead to faulty design and faulty inference for analytic problems.

It is possible, in an enumerative problem, to reduce errors of sampling to any specified level. In contrast, in an analytic problem, it is impossible to compute the risk of making a wrong decision. The author provides a number of examples, and pleads for greater care in the writing and teaching of statistical theory and inference.     

The Job Demands-Job Control Model and absence behaviour: results of a 3-year longitudinal study

Empirical results of earlier studies only marginally supported the relevance of Karasek's Job Demands-Job Control Model for absence behaviour. Since longitudinal studies with respect to these relations were largely lacking, a four-wave panel study was carried out using data from 1755 male employees of a technical maintenance firm in the public sector. Job demands, job control, physical working conditions, and the employee's age, education, and health were measured in one year and absenteeism in the same year and in the next 3 years. Data were analysed with linear regression and Poisson regression techniques. The Poisson regression technique was superior to the linear regression technique in explaining absence. Age, health and prior absence were the best predictors of later absence behaviour. With respect to the Job Demands-Job Control Model, the main findings of the study were (1) that job control was significantly associated with a low number of simultaneous and later absence days, and (2) that, contrary to expectations, job demands were also related to a low number of simultaneous and later absence days. These results hold when age, health, education, prior absence, and working conditions are controlled for. Job control and job demands did not predict later absence frequency. In the discussion it is suggested that a high level of job demands may not only be harmful for the well-being of employees but also work as 'a pressure to attend'.     

Using adaptive weighted least squares to reduce the lengths of confidence intervals

The author proposes an adaptive method which produces confidence intervals that are often narrower than those obtained by the traditional procedures. The proposed methods use both a weighted least squares approach to reduce the length of the confidence interval and a permutation technique to insure that its coverage probability is near the nominal level. The author reports simulations comparing the adaptive intervals to the traditional ones for the difference between two population means, for the slope in a simple linear regression, and for the slope in a multiple linear regression having two correlated exogenous variables. He is led to recommend adaptive intervals for sample sizes superior to 40 when the error distribution is not known to be Gaussian.     

The Renewed Search for Social Trusteeship: Cohen and Fitch on Social Justice and the City

It has become a commonplace to argue that in the face of a discredited Marxism, socialism must find an alternative basis for a renewed project. This article investigates two of these claims by Gerald Cohen and Bob Fitch. It does so with particular reference to the attempt by these authors to re-invoke, both wittingly and unwittingly, David Ricardo, John Stuart Mill, Henry George, and Auguste Comte among others as the source of a renewed left project. It takes as its special concern the way in which the supposed need to revivify "industry" in the late twentieth century parallels the often voiced need to revivify "agriculture" in the late nineteenth century as a means of staving off "underdevelopment."     

Hunger strikes: preventing harm to students.

When the health center encountered a student hunger strike, an initial search for medical information regarding fasting provided very little on which to build management decisions. The result of a more thorough evaluation of starvation literature is presented, along with survey responses from students who fasted. Starvation may produce many adverse events, including death. Yet, according to reports, acaloric fasts that include full water intake seem to be readily tolerated for 2 weeks in young, healthy adults. Our students included juice, sports drinks, and vitamins in their diets and completed their strike without major problems. Supplementation with carbohydrates and vitamins may improve the safety or comfort of a hunger striker, but clear proof of this effect does not exist.     

Cancer risk estimation for mixtures of coal tars and benzo(a)pyrene.

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.