A longitudinal study of the reciprocal nature of risk behaviors and cognitions in adolescents: What you do shapes what you think, and vice versa.

Adolescents' reckless driving, drinking, and smoking, along with their cognitions about these behaviors, were assessed in a 3-year longitudinal design. Consistent with most models of health behavior, the results indicated that health cognitions predict risk behavior. In addition, the current data demonstrate that increases in risk behavior are accompanied by increases in perceptions of vulnerability and prevalence and by decreases in the influence of concerns about health and safety. Furthermore, the changes in prevalence estimates and concern about health and safety predicted subsequent risk behavior. These results demonstrate reciprocity between risk behaviors and related cognitions and suggest that adolescents are aware of the risks associated with their behavior but modify their thinking about these risks in ways that facilitate continued participation in the behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adjustable audio watermarking algorithm based on DWPT and psychoacoustic modeling

This paper presents a novel adjustable audio watermarking method with high auditory quality by exploiting the discrete wavelet packet transform (DWPT), psychoacoustic modeling and distortion compensated-dither modulation (DC-DM) quantization. While the DWPT is used to divide the audio frames into several frequency sub-bands, the psychoacoustic model is intergraded to determine the appropriate sub-bands for watermarking and to control the number of embedded bits in each one. Then, the DC-DM technique is used to embed the watermark bits into the appropriate DWPT coefficients. The synchronization code technique is adopted in the proposed method to withstand desynchronization attacks. In order to achieve an adjustable watermarking scheme, two regulator parameters are provided to manage the capacity-robustness trade-off. The performance of the watermarking scheme is evaluated by examining different host audio signals under various watermarking attacks. The results show excellent imperceptibility of watermarked signals with an average ODG of ? 0.3. In addition, the proposed scheme provides strong robustness against the attacks with low capacity. However, high capacity (about 2500 bps) can be achieved while maintaining a reasonable robustness. A comparison with some state-of-the-art audio watermarking schemes reveals that the proposed method provides competitive results.     

The Politics of Local Environmental Management

Environmental management on the part of local government is now being accorded a high priority in certain parts of Australia. To date, for example, approximately 25 local councils in Victoria – either singly or jointly – have been involved in the development of Local Conservation Strategies (LCSs), most with some financial assistance from the Government of Victoria's Office of the Environment. The majority of these LCSs relate to urban rather than rural settings. There have been differences of approach depending upon such parameters as the initial professional training of the main officers concerned, the council's level of political commitment to the idea, and the socio-economic make-up of the local community.     

The effect of early cognitions on cigarette and alcohol use during adolescence.

The present study predicts cigarette and alcohol use in adolescence from the development of children's cognitions in the elementary years. Using latent growth modeling, the authors examined a model using data from 712 participants in the Oregon Youth Substance Use Project, who were in the 2nd through 5th grade at the 1st assessment and followed for 6 annual or semiannual assessments over 7 years. Growth in children's prototypes and subjective norms in the elementary years (Times 1 through 4) were related to their substance use in adolescence (Time 6) through their willingness and intentions (Time 5) to smoke and drink. Across the sample, for both substances, the intercept and slope of prototypes were either indirectly related to use through willingness or directly related to use. Both the intercept and slope of subjective norms were indirectly related to use of both substances through both willingness and intentions and directly related to cigarette use. Results suggest that elementary children have measurable cognitions regarding substance use that develop during the elementary years and predict use later in adolescence. These findings emphasize the need for prevention programs targeted at changing children's social images of substance users and encouraging more accurate perceptions of peers' use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychological profiles of purging bulimics, repeat dieters, and controls.

In Study 1, 29 female undergraduates who met Diagnostic and Statistical Manual of Mental Disorders (DSM-III) criteria for bulimia were compared with 2 nonbulimic groups drawn from the same S pool. One group consisted of 27 Ss who reported feeling dissatisfied with their weight and engaged in repeated dieting attempts but not bulimic behavior. The 2nd comparison group consisted of 27 Ss who reported feeling satisfied with their weight and not dieting within the last year. Measures included the Minnesota Multiphasic Personality Inventory (MMPI), Personal Attributes Questionnaire, and Tennessee Self-Concept Scale. All Ss scored in the normal range, but bulimics scored significantly higher than the 2 comparison groups on a number of clinical scales. Also, the bulimics and repeat dieters reported lower self-esteem than did the nondieting group. The major discriminating variables—psychopathic deviance, mania, and physical self-esteem—separated all 3 groups and accounted for 78% of the explained variance. Study 2 was conducted with 27 current bulimic women, 12 former bulimics, 29 nondieters, and 31 repeat dieters. Results confirm the importance of physical self-esteem and psychopathic deviance in differentiating between groups. This study also revealed that bulimics engaged in sexual activities and in the adolescent acting-out behaviors of drug and alcohol use more frequently, and at an earlier age, than did the 2 comparison groups. Implications for therapeutic interventions are discussed. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mysterious outbreaks of gastrointestinal illness associated with burritos supplied through school lunch programs

From October 1997 through March 1998, three outbreaks of gastrointestinal illness among school children were linked to company A burritos. In September 1998, a similar outbreak occurred in three North Dakota schools following lunches that included company B burritos. We conducted an investigation to determine the source of the North Dakota outbreak, identify other similar outbreaks, characterize the illness, and gather evidence about the cause. The investigation included epidemiologic analyses, environmental investigation, and laboratory analyses. In North Dakota, a case was defined as nausea, headache, abdominal cramps, vomiting, or diarrhea after lunch on 16 September 1998. Case definitions varied in the other states. In North Dakota, 504 students and staff met the case definition; predominant symptoms were nausea (72%), headache (68%), abdominal cramps (54%), vomiting (24%), and diarrhea (16%). The median incubation period was 35 min and median duration of illness was 6 h. Eating burritos was significantly associated with illness (odds ratio, 2.6; 95% confidence interval, 1.6 to 4.2). We identified 16 outbreaks that occurred in seven states from October 1997 through October 1998, affecting more than 1,900 people who ate burritos from two unrelated companies. All tortillas were made with wheat flour, but the fillings differed, suggesting that tortillas contained the etiologic agent. Results of plant inspections, tracebacks, and laboratory investigations were unrevealing. More than two million pounds of burritos were recalled or held from distribution. The short incubation period, symptoms, and laboratory data suggest that these outbreaks were caused by an undetected toxin or an agent not previously associated with this clinical syndrome. Mass psychogenic illness is an unlikely explanation because of the large number of sites where outbreaks occurred over a short period, the similarity of symptoms, the common food item, the lack of publicity, and the link to only two companies. A network of laboratories that can rapidly identify known and screen for unknown agents in food is a critical part of protecting the food supply against natural and intentional contamination.     

Families and risk: prospective analyses of familial and social influences on adolescent substance use.

Parental, peer, and older siblings' contributions to adolescents' substance use were investigated with 2 waves of panel data from 225 African American families. Structural equation modeling showed that older siblings' behavioral willingness (BW) to use substances at Time 1 (T1) predicted target adolescents' Time 2 (T2) use, controlling for other T1 variables. Regression analyses revealed an interaction between targets' and siblings' BW, such that targets were more likely to use at T2 if both they and their siblings reported BW at T1. This interaction was stronger for families living in high-risk neighborhoods. Finally, siblings' willingness buffered the impact of peer use on targets' later use: Low sibling BW was associated with less evidence of peer influence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Risk perceptions: Assessment and relationship to influenza vaccination.

Objective: Accurate measurement of beliefs about risk probability is essential to determine what role these beliefs have in health behavior. This study investigated the ability of several types of risk perception measures and of other constructs from health behavior theories to predict influenza vaccination. Design: Prospective study in which students, faculty, and staff at 3 universities (N = 428) were interviewed in the fall, before influenza vaccine was available, and again early in the next calendar year. Main Outcome Measure: Self-reported influenza vaccination. Results: Two interview questions that asked about feeling at risk and feeling vulnerable predicted subsequent behavior better (r = .44, p = .001) than 2 questions that asked for agreement or disagreement with statements about risk probability (r = .25, p = .001) or 4 questions that asked respondents to estimate the magnitude of the risk probability (r = .30, p = .001). Of the 4 perceived risk magnitude scales, a 7-point verbal scale was the best predictor of behavior. Anticipated regret was the strongest predictor of vaccination (r = .45, p = .001) of all constructs studied, including risk perceptions, worry, and perceived vaccine effectiveness. Conclusion: Risk perceptions predicted subsequent vaccination. However, perceived risk phrased in terms of feelings rather than as a purely cognitive probability judgment predicted better. Because neither feeling at risk nor anticipated regret is represented in the most commonly used theories of health behavior, the data suggest that these theories are missing important constructs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Long-term effects of appearance-based interventions on sun protection behaviors.

Objectives: To examine the longer term efficacies of exposure to UV photographs and photoaging information (e.g., wrinkles and age spots) for increasing sun protection intentions and behaviors of young adults. Design: Randomized controlled trial with 4- to 5-month and 12-month follow-ups. Main Outcome Measures: Participants' self-reported sun protection intentions assessed immediately after the interventions, and both self-reported sun protection behaviors and an objective assessment (via spectrophotometry) of skin color change measured at the end of summer (4-5 months following interventions) and 1 year following interventions. Results: Both interventions resulted in immediate positive effects on future sun protection intentions. Both interventions showed objective evidence of less skin darkening at the postsummer follow-up, with those in the photoaging information condition also reporting more sun protective behavior and continuing to show less skin darkening 1 year after intervention. There was also evidence that effects of photoaging information on subsequent skin color change were mediated by the earlier positive effect photoaging information had on participants' intentions to sun protect and their subsequent sun protection behaviors. Conclusions: UV photo and photoaging-information interventions each show promise as a brief and relatively inexpensive approach for motivating sun protection practices that may reduce skin cancer risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved)