An evaluation of the social and private efficiency of adoption: anaerobic digesters and greenhouse gas mitigation.

Climate science has begun to recognize the important role of non-carbon dioxide greenhouse gas emissions, including methane. Given the important contribution of methane, anaerobic digesters (ADs) on dairy farms in the U.S. present an opportunity to reduce greenhouse gas (GHG) emissions. We quantify the social and private costs and benefits of ADs that have been adopted in California and find that, despite high initial costs, large reductions in GHG emissions bring significant social benefits and represent good social investments given a $36 per-ton social cost of carbon. Subsidies that lower the initial private investment cost can help align socially and privately optimal adoption decisions.

College students' knowledge and health beliefs about AIDS: implications for education and prevention.

A questionnaire designed to measure the application of the dimensions of the Health Belief Model (HBM) to AIDS prevention and to practicing safer sex was administered to 139 undergraduates aged 22 years and under. Students generally had good knowledge about the facts of AIDS, which was consistent with other studies. We found an important difference between students' beliefs about practicing safer sex to prevent AIDS depending on whether their level of knowledge was high or low. The HBM posits that all of its dimensions must be present in order for belief to be followed by action. However, students with low knowledge indicated that the perceived barriers to practicing safer sex were higher than did students with high knowledge about AIDS. These results suggest that special efforts need to be made to teach students with low knowledge more about AIDS and that the barriers to safer sex can and should be overcome. There were no differences between students known to be sexually active compared with those who may or may not have been sexually active. One explanation was a possibly high number of students in the group identified as "perhaps sexually active" who actually were sexually active. Similarly, there were no differences between college students who did or did not know someone with AIDS, but this may have been due to the small number of students who did know such a person. Students' preferences for the format and methodology of AIDS education also were presented. In general, the students preferred small-group discussions and formats such as movies or panel discussions where they could remain "anonymous."(ABSTRACT TRUNCATED AT 250 WORDS)

HIV-related sexual behaviors of college students.

A follow-up study explored the prevalence of behavioral risk factors for HIV infection in a population of college students. Two hundred forty-three single students ranging in age from 17 to 24 years who identified themselves as heterosexual completed questionnaires related to planned and unplanned sexual intercourse and such other factors as alcohol and nonprescription drug use that might increase the risk of HIV infection. Forty-seven percent of the men and 57% of the women stated that they had had sexual intercourse from 1 to 5 times primarily because they were intoxicated, a phenomenon that increased with age until only 19% of those over 21 had never had sex because of intoxication. Seventeen percent of the sexually active men and 21% of the women said that they had used condoms. Nineteen percent of the men and 33% of the women acknowledged consenting to sexual intercourse because they felt awkward in refusing. The dangerous interaction between alcohol use and high-risk sexual activities suggested that college HIV prevention efforts should make the connection between the two risk factors explicit.

Using evaluation techniques to select health education programs.

Health educators often are faced with the job of selecting a new program to meet particular objectives. When one or more options is available, the selection process may involve the application of rather sophisticated evaluation skills whether or not the health educator is aware of the fact. By consciously applying evaluation techniques, health educators can increase the likelihood that a new program will meet their needs. The article provides guidelines for choosing an effective program by posing questions that normally are raised at the end of a program during the summative evaluation but are equally relevant at its beginning during the program selection stage. Seeking the answers to these questions before a program is implemented can contribute much toward ensuring the desired outcomes will be achieved.

Teenagers' beliefs about AIDS education and physicians' perceptions about them.

A survey of 189 Louisiana teenagers and 80 Louisiana family physicians revealed that the teenagers overwhelmingly preferred to learn about acquired immune deficiency syndrome (AIDS) from a physician. This result stimulated an interest in learning whether family physicians shared adolescents' opinions that they are the best teachers for AIDS education and whether family physicians understand adolescents' knowledge and beliefs about AIDS sufficiently well to be effective AIDS educators. Family physicians' responses to a questionnaire based, in part, on the Health Belief Model were compared with teenagers' responses about their knowledge, health beliefs, and preferred format and method of learning about AIDS. Results indicated that family physicians' predictions about teenagers' knowledge and beliefs about AIDS were not always accurate, but, except when physicians underestimated the teenagers' perceived obstacles to AIDS prevention, the data suggested that physicians would be effective in teaching teenagers about AIDS. Family physicians showed good agreement with teens in estimating their desired method and format for learning about AIDS, including their preference for a physician instructor.

Books as therapy for children of alcoholics.

Books can help child welfare professionals who work with children of alcoholics as an adjunct to other therapies and interventions. Fiction books used in bibliotherapy and nonfiction books directed at the COA, adult, and professional communities can all serve useful purposes. As with any other technique, there are limitations to its effectiveness. Children who are good readers and/or used to finding solutions for other kinds of needs in books will probably profit most. When combined judiciously with personal interaction, however, books can help professionals break through COAs' defensive barriers and meet the special needs of this difficult-to-reach, at-risk population.

Lay volunteers' knowledge and beliefs about AIDS prevention.

The imperative to inform the public about the risks of HIV-infection and AIDS, combined with an acute shortage of resources for doing so, has led to an unprecedented number of lay volunteers who are performing functions normally reserved for health professionals. In many communities, the general public may receive much of their information about HIV-transmission and AIDS prevention from lay volunteers who work for community-based AIDS awareness programs. Therefore, it would be of interest to know whether lay volunteers' own knowledge and beliefs about AIDS are accurate and consistent with promoting safer sex and if they are not so initially, whether they are readily amenable to change after training by health professionals. To investigate these issues, pre-/post-questionnaires were administered to lay persons in training to become volunteers for the NO/AIDS Task Force in New Orleans, Louisiana. Prior to training, lower knowledge volunteers differed from their higher knowledge peers on 2 of the 5 Health Belief Model (HBM) dimensions: perceived vulnerability (p .057) and barriers (p .002). After training, these differences disappeared, and all volunteers scored 100% on the knowledge section. Lay volunteers' opinions are also provided about where, in what format, and by whom adults and teenagers should be taught about AIDS.

The prevalence of type A personality in the children of alcoholics.

Three studies are reported which investigate the prevalency of an excess risk of type A personality in the children of alcoholics (COAs). Reports in the clinical literature suggest there is an excess risk of type A in COAs, but this has never been empirically demonstrated. The Matthews Youth Test for Health (MYTH) was administered to nonalcoholic mothers of 46 COAs and 65 matched controls to measure children's type A competitiveness and impatience-aggression. Results were significant only for greater impatience-aggression in COAs. In a second study, 104 COAs and controls matched for age, sex, race, and father's occupational status were rated by military fathers of intact families using MYTH. The results of the first study were not replicated for COAs, and there was no correlation between a father's Jenkins Activity Scale (JAS) score and his child's type A personality. A third study of 70 matched COAs and controls used the Hunter-Wolf A-B Rating scale, a self-rating scale for children and found no significant differences in children's type A personalities based on membership in an alcoholic family, sex, or birth order. It was concluded that the discrepancy between clinical reports and the present data may have been due to misperceptions about successful, hardworking COAs who, particularly in contrast to their more notorious siblings, may be viewed as "workaholics" and improperly labeled as type A personalities.

Comparison of the prevalence of type A behavior in boys and girls from two contrasting socioeconomic status groups.

The prevalence of Type A behavior in children from lower-class rural and upper-class urban backgrounds was compared using the Hunter-Wolf A-B Self-Rating Scale (H-W A-B). Analyses of variance were performed for two levels of socioeconomic status (SES), two levels of race (black and white), two levels of gender, and two levels of age (9-11 and 13-14). A significant difference for SES was found in the predicted direction with a greater prevalence of Type A being found among upper-urban children (p less than .001). There was also a significant effect for race (p less than .0001). Although there was a significant effect for gender with boys scoring higher (p less than .001), there was no difference between boys and girls within either SES group, and both boys and girls in the upper-urban group were more Type A than boys and girls in the lower-rural group (p less than .001). The possibility that the lack of sex differences within groups may reflect changing lifestyles for young women is discussed as a topic worthy of further epidemiological investigation.

Effects of Chemical Treatments upon Photosynthetic Parameters in Soybean Seedlings.

The effects of various chemical treatments upon photosynthesis, soluble leaf protein, CO(2) compensation point, and leaf light transmission in soybean, Glycine max (L.) Merr., seedlings were examined following varying response periods after application at 14 to 17 days postemergence. The compounds N(6)-benzyladenine (BA), 2-(4-chlorophenoxy)-2-methylpropanoic acid (CPMP), (4-chlorophenoxy)acetic acid (CPA), rhodanine-N-acetic acid (RAA), and 2,3,5-triiodobenzoic acid (TIBA) significantly increased soluble protein and decreased senescence, measured by leaf light transmission, at CO(2) concentrations below the compensation point in a survival chamber. All compounds except BA significantly decreased transmission values under ambient atmospheric conditions. In statistically significant experiments, applications of 3.49 millimolar CPMP increased net photosynthesis on a leaf area basis by an average of 14.4% at all trifoliolate positions with increases generally requiring response periods of 12 days or longer. RAA at 1.31 and 2.61 millimolar increased net photosynthesis by 19 to 36% following 13-day response periods. CPMP and other compounds tested had no effect upon the CO(2) compensation point after 4- to 8-day response periods. The effects of CPMP and RAA upon net photosynthesis and soluble protein appeared to involve a combined stimulation of protein synthesis and an antisenescent effect. There were no indications that any of the photosynthetic changes observed resulted from direct differential effects upon ribulose bisphosphate carboxylase-oxygenase. The assays for soluble protein and light transmission responded more consistently to the chemicals than did photosynthesis.

Detection of chemicals inhibiting photorespiratory senescence in a large scale survival chamber.

A large scale survival chamber was developed as a screen for detecting chemical treatments that extend the survival time of illuminated soybean seedlings at CO(2) concentrations below the compensation point. In theory, extended survival should indicate potential for improved crop performance via decreased photorespiration and increased photosynthetic efficiency. An automated control system regulated CO(2) concentrations, temperature and plant watering during a continuous CO(2)-removal photoperiod of 72 hours. An endogenously controlled circadian rhythm of net photosynthesis occurred throughout the continuous light treatment.Spray applications of 3.49 millimolar 2-(4-chlorophenoxy)-2-methylpropanoic acid (CPMP) significantly decreased leaf chlorophyll loss, compared with the control, after 72 hours of subcompensation-point stress. Treatment with CPMP also consistently increased leaf chlorophyll per unit area under nonstress greenhouse conditions. These effects may be due to increases in specific leaf weight produced by CPMP although the compound did not consistently act as a height retardant. The compound, 3-butyl-2-hydroxy-4H-pyrido[1,2-a]pyrimidin-4-one (BHPP), inhibited senescence under low CO(2) conditions but did not decrease leaf light transmission at ambient CO(2) levels. The cytokinin N(6)-benzyladenine (BA) retarded low CO(2) stress senescence although greening effects were not observed. Neither 2-hydroxy-3-butynoic acid (HBA) nor its butyl ester, inhibitors of glycolate oxidase, influenced low CO(2) survival. Cyclohexanecarboxylic acid (CHCA) and sodium naphthenate had no effect upon subcompensation-point senescence.Antisenescence effects of CPMP, BHPP, and BA do not appear to be directly attributable to effects upon the competing carbon paths of photosynthesis and photorespiration. Protection against low CO(2) stress and increased chlorophyll synthesis under nonstress conditions may represent separate effects upon plastids by some of the compounds. This screen will identify compounds which inhibit photorespiratory senescence without decreasing the CO(2) compensation point.