Structure-property relationship of anilino-squaraines in organic solar cells.

Soluble molecular semiconductors are a promising alternative to semiconducting polymers in the field of organic photovoltaics. Here, three custom-made symmetric 1,3-bis(N,N-alkylated-2,6-dihydroxy-anilino)squaraines containing systematic variations in their molecular structures are compared regarding their applicability as donor materials in bulk-heterojunction solar cells. The terminal substitution pattern of the squaraines is varied from cyclic over linear to branched including a stereogenic center. Single crystal structures are determined, and, in the case of chiral squaraine, unusual formation of stereoisomer co-crystals is revealed. The thin film absorbance spectra show characteristic signatures of H- and J-bands or hint at the formation of tautomers. The general feasibility of these model compounds for photovoltaic applications is studied by light-induced electron spin resonance spectroscopy. The impact of the different molecular substitution patterns on aggregation behavior and, consequently, their optoelectronic solid state properties including charge carrier mobility and finally the solar cell performance are investigated.

Suppression of soft nuclear bremsstrahlung in proton-nucleus collisions.

Photon energy spectra up to the kinematic limit have been measured in 190 MeV proton reactions with light and heavy nuclei to investigate the influence of the multiple-scattering process on the photon production. Relative to the predictions of models based on a quasifree production mechanism, a strong suppression of bremsstrahlung is observed in the low-energy region of the photon spectrum. We attribute this effect to the interference of photon amplitudes due to multiple scattering of nucleons in the nuclear medium.

Examination of the short-term efficacy of a parent intervention to reduce college student drinking tendencies.

The research evaluated the efficacy of an intervention to reduce the onset and extent of binge drinking during the 1st year of college. The approach was on influencing the students before they start college, through their parents, during the critical time between high school graduation and the beginning of college. Specifically, parents were educated about binge drinking and how to convey information to their teens, and then encouraged to talk with their teens just before their teens embarked on their college education. Teens whose parents implemented the intervention materials were compared with a control sample during their 1st semester on drinking outcomes, perceptions about drinking activities, perceived parental and peer approval of drinking, and drinking-related consequences. As anticipated, teens in the treatment condition were significantly different (p < .05) on nearly all outcomes in the predicted directions (e.g., lower drinking tendencies, drinking consequences). The benefits of a parent-based intervention to prevent college drinking are discussed.

Binge-drinking-related consequences in college students: role of drinking beliefs and mother-teen communications.

The present research contrasted theoretical models depicting the nature of the relation among drinking beliefs, drinking tendencies, and behavioral consequences in 266 incoming freshman college students. It also examined the theoretical relations between mother-teen communications and drinking beliefs relevant to behavioral consequences. The findings revealed direct relations between binge-drinking consequences and the drinking beliefs: Alcohol can make positive transformations, can enhance social behavior, and can increase negative affect and normative approval. Direct relations were not observed between consequences and the drinking beliefs regarding physical risk and health orientation. Finally, the present research found consistent support for the relation between mother-teen communications and drinking beliefs relevant to binge-drinking consequences.

Modeling tanning salon behavioral tendencies using appearance motivation, self-monitoring and the theory of planned behavior.

The constructs of appearance motivation and self-monitoring were added to the Theory of Planned Behavior in the prediction of tanning salon use in young people. The variables of the Theory of Planned Behavior proved effective at predicting tanning salon behavioral intentions and tendencies. Intentions and perceived behavioral control predicted tanning salon behavioral tendencies, while attitudes, subjective norms and perceived behavioral control predicted tanning salon behavioral intentions. Appearance motivation did not show any direct or interaction effects in the prediction of tanning salon behavioral intentions. It did, however, prove superior to health orientation in the prediction of tanning salon attitudes. Self-monitoring interacted with subjective norms in the prediction of tanning salon intentions, with high self-monitors showing stronger subjective norm-intention relationships than low self-monitors. These results imply that appearance-related interventions could prove efficacious in reducing young people's tanning salon behavioral tendencies. Furthermore, it may be important to consider individual's self-monitoring status when targeting skin cancer prevention information to young people.

Coherent bremsstrahlung in the alpha + p system at 50 MeV/nucleon

Photons originating from coherent bremsstrahlung have been measured over a large dynamic range for the reaction of 200 MeV alpha particles with protons. At low photon energies the bremsstrahlung spectrum exhibits the classical behavior with an approximate 1/E(gamma) shape. At higher photon energies there is a pronounced contribution from capture into the unbound ground state and first excited state of 5Li. These results allow one, for the first time, to test theoretical models for a consistent description of bremsstrahlung and radiative capture in a complex system. Calculations predict both features qualitatively but fail to account for their relative importance.

College student drinking: an examination of theoretical models of drinking tendencies in freshmen and upperclassmen.

OBJECTIVE: The present research contrasted theoretical models of college student drinking tendencies (normative, social control, maturing out). METHOD: Three groups of students (N = 364; 62. 1% female) from a moderately sized northwestern university were examined: traditional freshmen, nontraditional freshmen and upperclassmen. Participants completed measures assessing drinking tendencies, drinking consequences and drinking beliefs. RESULTS: Support for a given theoretical model was dependent upon which outcome variables were being examined (e.g., drinking tendencies vs drinking consequences). Nontraditional freshmen were similar to their traditional freshmen counterparts in the amount of alcohol they consumed but were more like upperclassmen in the experience of consequences of drinking alcohol. Examination of drinking beliefs yielded inconsistent model support. CONCLUSIONS: It appears that different types of college students drink for different reasons, suggesting a "one size fits all" intervention is less likely to be effective. The findings are discussed with respect to different interventions for changing drinking tendencies, drinking consequences and drinking beliefs, and the timing of those interventions.

Examination of cognitive variables relevant to sunscreen use.

The present study is an examination of the underlying psychological variables relevant to a sun-damage preventive behavior, sunscreen use. The focus of the research was to examine cognitive predictors of sunscreen use, utilizing a decision theoretic framework. Two hundred thirty subjects were recruited from psychology classes and administered questionnaires assessing sunscreen behavioral tendencies, attitudes toward sunscreen use, and internal- and external-based cognitions relevant toward sunscreen use. In contrast to previous work that had examined only one or two of these predictor variables in isolation, the present study evaluated the relative impact of these variables on sunscreen use tendencies. The findings revealed evidence of a multivariate model (using structural equation modeling; LISREL VIII) relating perceived need for, perceived efficacy of, perceived consequences of, and social normative influences on sunscreen use. The findings are discussed with respect to improving the effectiveness of short-term education efforts to increase sunscreen use.

Examination of judgments of drunkenness, binge drinking, and drunk-driving tendencies in teens with and without a family history of alcohol abuse.

BACKGROUND: The present study examined judgment processes of individuals with and without a family history of alcohol abuse. Despite the alarming statistics involving alcohol-related consequences in this population, very little is known about what judgment processes they use or how beneficial these processes are at preventing intoxication and alcohol-related consequences. METHODS: Participants were 270 individuals, 16-18 years old, screened on the basis of the history of family alcohol abuse. Individuals were asked to (1) make judgments of drunkenness in relation to the legal limits in response to factorially manipulated external cues on number of drinks, time taken to consume, and type of beverage, using the methodology of Jaccard and Turrisi (1987), and (2) answer several questions regarding their alcohol-related behaviors. RESULTS: Our results indicated that individuals with a positive family history of alcohol abuse were more likely to make judgmental errors and underestimate their drunkenness relative to individuals without a positive family history of alcohol abuse. Moreover, the errors in judgments were more pronounced in situations involving moderate to heavy alcohol consumption. Finally, family history was found to moderate the relationship between underestimation errors and drinking, and drinking and driving tendencies. For individuals with a positive family history of alcohol abuse, the more they tended to underestimate their drunkenness, the more likely they were to binge drink and drive after drinking. CONCLUSIONS: The findings suggest that judgmental errors tend to be an important process variable in the relationship between family history and alcohol-related behavioral tendencies. The findings are discussed with respect to potential behavioral antecedents (e.g., student binge drinking) and development of prevention programs geared toward training students to make more accurate judgments, using external cues.

Parent-based intervention strategies to reduce adolescent alcohol-impaired driving.

OBJECTIVE: To review selected issues to consider when designing parent-based interventions for reducing alcohol-impaired driving in adolescent populations and to present a theoretical framework for analyzing such behavior. METHOD: The existing literature on alcohol-impaired driving and parent influences is considered based on a literature review of contemporary social science journals. Data also are presented from a survey of junior and senior high school students in the Capitol District of New York. CONCLUSIONS: Parent-based approaches are promising and represent an additional tool in the armament of strategies to reduce alcohol-impaired driving. Programs should focus on variables that are amenable to change (cognitions and attitudes), conduct preliminary studies to isolate relevant attitudes and cognitions for the target population of interest, formulate strategies that recognize the numerous demands in a parent's life and take into account existing theoretical frameworks on alcohol-impaired driving in adolescents.

A cognitive analysis of server intervention policies: perceptions of bar owners and servers.

OBJECTIVE: The present study examined the underlying psychological variables relevant to alcohol server intervention policies. The focus of the research was the theoretical examination of college bar owners' and servers' attitudes and beliefs about server intervention policies. METHOD: Owners (n = 185) and servers (n = 185) of college bars were asked about their attitudes and perceived cognitive outcomes regarding server intervention policies. RESULTS: Although the findings revealed no statistical differences between owners and servers on their attitudes toward the different server intervention policies, statistical differences were found between the different policies (p < .05). Favorable policies focused on providing services to customers, whereas unfavorable policies focused on limiting the sales of alcohol. Finally, structural equation modeling revealed perceived cognitive outcomes related to the attitudes toward different server intervention policies. CONCLUSIONS: According to the present study's theoretical orientation, the attitudes are likely to have a direct influence on the adoption of policies or, on the part of the server, compliance with the policies. These attitudes toward the policies were found to be a function of the perceived hassle of implementing the policies and how effective the policy was in preventing driving under the influence.

An examination of psychological variables relevant to artificial tanning tendencies.

Cognitions relevant to tanning salon decision making were studied using Jaccard's Theory of Alternative Behavior (J. Jaccard. Journal of Experimental Social Psychology1981; 17: 286-307). Questionnaires were administered assessing tanning salon use, attitudes toward tanning salon use, attitudes toward reasonable behavioral alternatives, and cognitive variables underlying these variables. Tanning salon use reports were very high in this sample. The results support the notion that young people make decisions regarding using tanning salons based on the behavioral alternatives available to them. Specifically, subjects with stronger preferences for using clothing to enhance appearance were less likely to use tanning salons. Furthermore, the multivariate approach used clearly delineates the specific cognitive beliefs and orientations that might be targeted to change these attitudes. The relevance of these findings to skin cancer prevention is discussed.

Examination of cognitive variables relevant to sunbathing.

This study examined cognitions relevant to sunbathing decision-making in college-aged subjects. Using Jaccard's (1981) theory of alternative behavior as a guiding model, 263 subjects were recruited from psychology classes and administered questionnaires assessing their sunbathing behavioural tendencies, attitudes toward sunbathing, attitudes toward reasonable behavioral alternatives to sunbathing, and cognitive variables underlying these attitudinal variables. The fits of models predicting sunbathing attitudes and sunbathing behavioural tendencies (evaluated using covariate structural equations modeling techniques; LIS-REL VIII) were good for all models tested. In contrast to previous work, the results of this study support the notion that young people will make their decisions regarding sunbathing based on the behavioral alternatives available to them (i.e., generally the one that they prefer most). Furthermore, the multivariate approach used clearly delineates the specific cognitive beliefs and orientations that might be targeted to change these attitudes. The relevance of these findings to skin cancer prevention interventions is discussed.

Application of Azjen's theory of planned behavior to predict sunbathing, tanning salon use, and sunscreen use intentions and behaviors.

Ajzen's (1988) theory of planned behavior (TOPB) was used to examine psychological determinants of high-risk UV radiation exposure-related behaviors (sunbathing, tanning salon use, and sunscreen use). Undergraduates at a midsized southeastern university were assessed on their psychological and behavioral tendencies toward high-risk UV radiation exposure-related behaviors. The results generally supported the utility of the TOPB as an explanatory model for high-risk behavior. Attitudes were strongly associated with high-risk intentions (e.g., not utilize sunscreen, use salons), whereas subjective norms were less so. Perceived behavioral control was found to moderate the relationship among attitudes, norms, and intentions to sunbathe and tan at a salon. Implications for intervention strategies and future model building in this area are discussed.

Cognitive and attitudinal factors in the analysis of alternatives to drunk driving.

The present study examined cognitive and attitudinal factors relevant to drunk-driving tendencies in individuals having zero, one and multiple drunk-driving convictions. Results indicate that the awareness of consequences of being in an accident was related to driving record but not to drunk-driving tendencies. In contrast, the awareness of consequences of being arrested for drunk driving (e.g., receiving fines, having one's name appear in the news and having a criminal record) was negatively related to drunk-driving tendencies. Attitudes toward alternatives to drunk driving (e.g., take a taxi, call a friend) were also negatively related to drunk-driving tendencies. The findings are discussed with respect to developing prevention programs.

The Detection and Interpretation of Interaction Effects Between Continuous Variables in Multiple Regression.

issues in the detection and interpretation of interaction effects between quantitative variables in multiple regression analysis are discussed. Recent articles by Cronbach (1987) and Dunlap and Kemery (1987) suggested the use of two transformations to reduce "problems" of multicollinearity. These transformations are discussed in the context of the conditional nature of multiple regression with product terms. It is argued that although additive transformations do not affect the overall test of statistical interaction, they do affect the interpretational value of regression coefficients. Factors other than multicollinearity that may account for failures to observe interaction effects are noted.