Vulnerability to adverse consequences of drinking and problem drinker status as predicted by risky drinking behaviours, drug use, sex differences and affect : a test of multiple models /

Although alcohol problems and alcohol consumption are related, consumption does not fully account for differences in vulnerability to alcohol problems. Therefore, other factors should account for these differences. Based on previous research, it was hypothesized that risky drinking behaviours, illicit and prescription drug use, affect and sex differences would account for differences in vulnerability to alcohol problems while statistically controlling for overall alcohol consumption. Four models were developed that were intended to test the predictive ability of these factors, three of which tested the predictor sets separately and a fourth which tested them in a combined model. In addition, two distinct criterion variables were regressed on the predictors. One was a measure of the frequency that participants experienced negative consequences that they attributed to their drinking and the other was a measure of the extent to which participants perceived themselves to be problem drinkers. Each of the models was tested on four samples from different populations, including fIrst year university students, university students in their graduating year, a clinical sample of people in treatment for addiction, and a community sample of young adults randomly selected from the general population. Overall, support was found for each of the models and each of the predictors in accounting for differences in vulnerability to alcohol problems. In particular, the frequency with which people become intoxicated, frequency of illicit drug use and high levels of negative affect were strong and consistent predictors of vulnerability to alcohol problems across samples and criterion variables. With the exception of the clinical sample, the combined models predicted vulnerability to negative consequences better than vulnerability to problem drinker status. Among the clinical and community samples the combined model predicted problem drinker status better than in the student samples.

Menstrual status and thermoregulatory responses of active adolescents during exercise in a cold environment

This study examined the interactions between the reproductive status and the thermoregulatory responses during exercise in the cold in girls involved in competitive sports. Four girls with established menstrual cycles comprised the eumenorrheic menarcheal group (EM) and 5 non-menstruating girls comprised the pre-menarcheal group (PM). During the first visit maximal oxygen consumption, height, weight and percent body fat (%BF) were measured. The second visit involved: a determination of metabolic rate in thermoneutrality (21°C) involving 10-min rest and 20-min cycling (30% of VCL max), and a cold stress test (5°C, 40% humidity, <0.3 m/s air velocity) involving 20-min rest and 40-min cycling (30% of VCL max.). Subjects in the EM group were tested twice in the chamber during the follicular and luteal phases. Pre-menarcheal subjects were found to have significantly (p<0.05) lower core temperatures during the final stages of cold exposure. Overall, body fat was not significantly correlated with core temperature in the cold, however there was a significant surface-to-mass ratio difference between the groups. While in the follicular phase, EM girls had a higher core temperature during cold exposure. Therefore, reproductive hormonal status seems to be an important factor in terms of cold tolerance in females during adolescence.

The relationship between self-serving cognitive distortions and bullying behaviours among elementary school children /

The purpose ofthe study was to examine the relationshq) between self-serving cognitive distortions and involvement in bullying behaviours. While relationships were e}q)k)red for both bullies and victims, the bully represented the main focus ofthis research. The participants ofthis study were 206 elementary school children in grades 5, 6, 7, and 8 from a school board in South Western Ontario. Participants conq>leted a 2- part self-report questionnaire within a 1-week time period. Part I aimed to measure self-serving cognitive distortions, while Part II was designed to assess selfreports of bullying behaviours. Analyses revealed that a significant direct relationship existed between children's self-serving cognitive distortions and bullying others. More specifically, children's self-serving cognitive distortions were moderately correlated with bullying others (r = .50, p< 0.01). This finding was consistent for both male and female participants. In addition, significant moderate correlations also existed between each ofthe 9 subscales ofself-serving cognitive distortions and bullying others. In regard to the relationship between children's self-serving cognitive distortions and victimization, a low significant direct relationshq) was found (r = .22 p<0.01). This finding was consistent for both male and female participants. The results ofthis study are discussed in terms oftheir theoretical, as well as applied implications.

Stress, social support, and health risk behaviours as mediators of the forgiveness-health relation /

The mediating roles of stress, social support, and health risk behaviours in the relationships between dispositional forgiveness and mental and physical health were examined. Participants were 748 undergraduate students (554 women, 194 men) entering their first year of studies at Brock University. Participants, ranging in age from 17 to 25 years, completed the Brock University First Year Health Study and were provided monetary compensation. Dispositional forgiveness, stress, social support, health risk behaviours, mental health, and physical health were measured using self-report methods. The data were analyzed separately for women and men because there were significant mean differences on many of the study'S variables. Analyses revealed that the mediated relationships between dispositional forgiveness and health were generally stronger for women than men. Stress was the most robust mediator of the forgiveness-health relation for both women and men. The only health risk behaviour that mediated the forgivenesshealth relation was physical fitness and this result was found for women only. Social support mediated several of the relationships between forgiveness and health but not others. Results were discussed with reference to the literature on forgiveness and health. Several directions for future research were offered, such as conducting longitudinal research designs to assess the direction of causality better, investigating moderator variables of the forgiveness-health relation, and building models, which incorporate multiple mediators using structural equation modelling techniques.

Towards the development of a questionnaire of post transgression motives and behaviours /

The primary purpose of this study was to develop a questionnaire that assesses both forgiveness-seeking motives and behaviours. This questionnaire was based on the premise that, following the commitment of an offense in the context of a relationship, a perpetrator will be motivated to reduce the damage that has taken place. The . ' questionnaire examined several motives that a perpetrator might have for seeking forgiveness. These motives were divided into five proposed domains of posttransgression concerns: God, Self, Victim, Others/Society, and Relationship. Within these domains, the following more specific types of concern were explored: Avoidance of punishment, concern about public image, emotional well-being, self-image, sense of fairness/justice, loss of relationship, loss or gain of power, and loss of ability to trust. The questionnaire also assessed which behaviours (approach and avoidance) a perpetrator might use in order to address these concerns. In addition, this study explored whether or not the severity of the situation and the personality of the perpetrator influenced post transgression motives and behaviours. Participants were 221 individuals from the community and Brock University. They filled out a questionnaire package that assessed personality traits, social desirability, and forgiveness-seeking motives and behaviours. In order to answer items assessing motives and behaviours, participants were asked to imagine themselves as perpetrators in three hypothetical transgression scenarios. These scenarios ranged in severity fi^om low to high. Participants were asked to rate their motives and behaviours both in an immediate time frame (immediately following the transgression) and in the long-term (in order to move on from the situation). Results indicated that the motivation items could be classified into the following subscales:Concern about God, Damaged Self-worth Concerns, Justice Concerns, Impression Management Concerns, Victim and Others Concerns, and Relationship Concerns. The behaviour items formed the following subscales: Approach, Avoidance, Denial and Hiding, and Groveling. Results also indicated differences in motivations and behaviours based on the severity of the situation as well as the personality (assessed using the HEXACO inventory) of the perpetrator.

Cues to action : do they result in belief and behavioural change in women?

With incidence rates of osteoporosis increasing (Osteoporosis Canada, 2007), preventative efforts to minimize costs associated with condition diagnosis are a public health priority. Cues to action are specific internal (e.g., physical symptoms, family member with a condition) or external stimuli (e.g., public service announcements, health education campaigns) that are necessary to trigger appropriate health behaviours and serve to create an awareness of the health threat (Mattson, 1999). To date, limited understanding of the scope of influence cues to action have on health beliefs and behaviour associated with osteoporosis is known. The present investigation was designed to address this gap in the literature. More specifically, the influence of cues to action, a public service announcement (PSA) developed by Osteoporosis Canada and a bone screening by way of Quantitative Ultrasound, on health beliefs and health-enhancing physical activity (HEPA) across a four week period was investigated. Peri-and postmenopausal women (N= 174) were randomly assigned to one of three conditions 1) an osteoporosis public service announcement (PSA) condition; 2) a bone screening condition via quantitative ultrasound techniques, and 3) a PSA attention control condition. Health beliefs associated with osteoporosis were taken at three time points: prior to the cue to action intervention, immediately following the intervention, and four weeks post intervention. Knowledge of osteorporosis risk factors and HEP A were assessed pre and post-intervention only. Results of a regression analysis suggested that baseline health beliefs predicted baseline HEPA (R2 adj = .24; F (9, 161) = 6.49,p = .000; 95% CI = .12 - .35) with exercise barriers (p = -.33) being a negative predictor and health motivation (p = .21) being a positive predictor of HEP A. Baseline health beliefs predicted With incidence rates of osteoporosis increasing (Osteoporosis Canada, 2007), preventative efforts to minimize costs associated with condition diagnosis are a public health priority. Cues to action are specific internal (e.g., physical symptoms, family member with a condition) or external stimuli (e.g., public service announcements, health education campaigns) that are necessary to trigger appropriate health behaviours and serve to create an awareness of the health threat (Mattson, 1999). To date, limited understanding of the scope of influence cues to action have on health beliefs and behaviour associated with osteoporosis is known. The present investigation was designed to address this gap in the literature. More specifically, the influence of cues to action, a public service announcement (PSA) developed by Osteoporosis Canada and a bone screening by way of Quantitative Ultrasound, on health beliefs and health-enhancing physical activity (HEPA) across a four week period was investigated. Peri-and postmenopausal women (N= 174) were randomly assigned to one of three conditions 1) an osteoporosis public service announcement (PSA) condition; 2) a bone screening condition via quantitative ultrasound techniques, and 3) a PSA attention control condition. Health beliefs associated with osteoporosis were taken at three time points: prior to the cue to action intervention, immediately following the intervention, and four weeks post intervention. Knowledge of osteorporosis risk factors and HEP A were assessed pre and post-intervention only. Results of a regression analysis suggested that baseline health beliefs predicted baseline HEPA (R2 adj = .24; F (9, 161) = 6.49,p = .000; 95% CI = .12 - .35) with exercise barriers (p = -.33) being a negative predictor and health motivation (p = .21) being a positive predictor of HEP A. Baseline health beliefs predicted

The effectiveness of a health versus appearance message on pregnant women's intentions to exercise postpartum : the moderating role of self-monitoring

Despite the confimied health benefits of exercise during the postpartum period, many new mothers are not sufficiently active. The present research aimed to examine the effectiveness of 2 types of messages on intention to exercise after giving birth on 2 groups of pregnant women (low and high self-monitors) using the Theory of Planned Behavior as a theoretical basis. Participants were 2 1 8 pregnant women 1 8 years of age and older (Mean age = 27.9 years, SD = 5.47), and in their second or third trimester. Women completed a demographics questionnaire, a self-monitoring (SM) scale and the Godin Leisure Time Exercise Questionnaire for current and pre-pregnancy exercise levels. They then read one of two brochures, describing either the health or appearance benefits of exercise for postpartum women. Women's attitudes, social norms, perceived behavioral control, and intentions to exercise postpartum were then assessed to determine whether one type of message (health or appearance) was more effective for each group. A MANOVA found no significant effect (p>0.05) for message type, SM, or their interaction. Possible reasons include the fact that the two messages may have been too similar, reading any message about exercise may result in intentions to exercise, or lack of attention given to the brochure. Given the lack of research in this area, more studies are necessary to confirm the present results. Two additional exploratory analyses were conducted. Pearson correlations found higher levels of pre-pregnancy exercise and current exercise to be associated with more positive attitudes, more positive subjective norms, higher perceived behavioral control, and higher intention to exercise postpartum. A hierarchical regression was conducted to determine the predictive utility of attitudes, subjective norms, and perceived behavioral control on intention for each self-monitoring group. Results of the analysis demonstrated the three independent variables significantly predicted intention (p < .001) in both groups, accounting for 58-62% of the variance in intention. For low self-monitors, attitude was the strongest predictor of intention, followed by perceived behavioral control and subjective norm. For high self-monitors, perceived behavioral control was the strongest predictors, followed by attitudes and subjective norm. The present study has practical and real world implications by contributing to our understanding of what types of messages, in a brochure format, are most effective in changing pregnant women's attitudes, subjective norm, perceived behavioral control and intention to exercise postpartum and provides ftirther support for the use of the Theory of Planned Behavior with this population.

The effect of elevated muscle fluid volume on indices of muscle damage following an acute bout of eccentric exercise

The primary purpose of the current investigation was to develop an elevated muscle fluid level using a human in-vivo model. The secondary purpose was to determine if an increased muscle fluid content could alter the acute muscle damage response following a bout of eccentric exercise. Eight healthy, recreationally active males participated in a cross-over design involving two randomly assigned trials. A hydration trial (HYD) consisting of a two hour infusion of a hypotonic (0.45%) saline at a rate of 20mL/minVl .73m"^ and a control trial (CON), separated by four weeks. Following the infusion (HYD) or rest period (CON), participants completed a single leg isokinetic eccentric exercise protocol of the quadriceps, consisting of 10 sets of 10 repetitions with a one minute rest between each set. Muscle biopsies were collected prior to the exercise, immediately following and at three hours post exercise. Muscle analysis included determination of wet-dry ratios and quantification of muscle damage using toluidine blue staining and light microscopy. Blood samples were collected prior to, immediately post, three and 24 hours post exercise to determine changes in creatine kinase (CK), lactate dehydrogenase (LD), interleukin-6 (IL-6) and Creactive protein (CRP) levels. Results demonstrated an increased muscle fluid volume in the HYD condition following the infusion when compared to the CON condition. Isometric peak torque was significantly reduced following the exercise in both the HYD and CON conditions. There were no significant differences in the number of areas of muscle damage at any of the time points in either condition, with no differences between conditions. CK levels were significantly greater 24hour post exercise compared to pre, immediately and three hours post similarly in both conditions. LD in the HYD condition followed a similar trend as CK with 24 hour levels higher than pre, immediately post and three hours post and LD levels were significantly greater 24 hours post compared to pre levels in the CON condition, with no differences between conditions. A significant main effect for time was observed for CRP (p<0.05) for time, such that CRP levels increased consistently at each subsequent time point. However, CRP and IL-6 levels were not different at any of the measured time points when comparing the two conditions. Although the current investigation was able to successfully increase muscle fluid volume and an increased CK, LD and CRP were observed, no muscle damage was observed following the eccentric exercise protocol in the CON or HYD conditions. Therefore, the hypotonic infusion used in the HYD condition proved to be a viable method to acutely increase muscle fluid content in in-vivo human skeletal muscle.

The acute effects of differential dietary fatty acids on PDHa activity in human skeletal muscle at the onset of exercise

Pyruvate dehydrogenase (PDH) is an important regulator of carbohydrate oxidation during exercise and its activity can be down-regulated by an increase in dietary fat. The purpose of this study was to determine the acute metabolic effects of differential dietary fatty acids on the activation of PDH in its active form (PDHa) at rest and at the onset of moderate-intensity exercise. University-aged male subjects (n=7) underwent 2 fat loading trials spaced at least 2 weeks apart. Subjects consumed saturated (SFA) or polyunsaturated (PUFA) fat over the course of 5 hours. Following this, participants cycled at 65% VO2 max for 15 min. Muscle biopsies were taken prior to and following fat loading and at 1 min exercise. Plasma free fatty acids increased from 0.15 ± 0.07 to 0.54 ± 0.19 mM over 5 hours with SFA and from 0.1 1 ± 0.04 to 0.35 ±0.13 mM with PUFA. PDHa activity was unchanged following fat loading, but increased at the onset of exercise in the SFA trial, from 1 .4 ± 0.4 to 2.2 ± 0.4 /xmol/min/kg wet wt. This effect was negated in the PUFA trial (1 .2 ± 0.3 to 1 .3 ± 0.3 pimol/min/kg wet wt.). PDH kinase (PDK) was unchanged in both trials, suggesting that the attenuation of PDHa activity with PUFA was a result of changes in the concentrations of intramitochondrial effectors, more specifically intramitochondrial NADH or Ca^*. Our findings suggest that attenuated PDHa activity participates in the preferential oxidation of PUFA during moderateintensity exercise.

Effects of dietary restraint and oral contraceptives on bone strength and bone turnover in young women

ABSTRACT Introduction The purpose of this study was to assess specific osteoporosis-related health behaviours and physiological outcomes including daily calcium intake, physical activity levels, bone strength, as assessed by quantitative ultrasound, and bone turnover among women between the ages of 18 and 25. Respective differences on relevant study variables, based on dietary restraint and oral contraceptive use were also examined. Methods One hundred women (20.6 ± 0.2 years of age) volunteered to participate in the study. Informed written consent was obtained by all subjects prior to participation. The study and all related procedures were approved by the Brock University Research Ethics Board. Body mass, height, relative body fat, as well as chest, waist and hip circumferences were measured using standard procedures. The 10-item restrained eating subscale of the Dutch Eating Behaviour Questionnaire (DEBQ) was used to assess dietary restraint (van Strien et al., 1986). Daily calcium intake was assessed by the Rapid Assessment Method (RAM) (Hertzler & Frary 1994). Weekly physical activity was documented by the 4-item Godin Leisure-Time Exercise Questionnaire (Godin & Shephard 1985). Bone strength was determined from the speed of sound (SOS) as measured by QUS (Sunlight 7000S). SOS measurements (m/s) were taken of the dominant and non-dominant sides of the distal one third of the radius and the mid-shaft of the tibia. Resting blood samples were collected from all subjects between 9am and 12pm, in order to evaluate the impact of lifestyle factors on biochemical markers of bone turnover. Blood was collected during the early follicular phase of the menstrual cycle (approximately days 1-5) for all subjects. Samples were centrifliged and the serum or plasma was aliquoted into separate tubes and stored at -80°C until analysis. The bone formation markers measured were Osteocalcin (OC), bone specific alkaline phosphatase (BAP) and 25-OH vitamin D. The bone resorption markers measured were the carboxy (CTx) and amino (NTx) terminal telopeptides of type-I collagen crosslinks. All markers were assessed by ELISA. Subjects were divided into high (HDR) and low dietary restrainers (LDR) based on the median DEBQ score, and also into users (BC) and non-users (nBC) of oral contraceptives. A series of multiple one way ANOVA's were then conducted to identify differences between each set of groups for all relevant variables. A two-way ANOVA analysis was used to explore significant interactions between dietary restraint and use of oral contraceptives while a univariate follow-up analysis was also performed when appropriate. Pearson Product Moment Correlations were used to determine relationships among study variables. Results HDR had significantly higher BMI, %BF and circumference measures but lower daily calcium intake than LDR. There were no significant differences in physical activity levels between HDR and LDR. No significant differences were found between BC and nBC in body composition, calcium intake and physical activity. HDR had significantly lower tibial SOS scores than LDR in both the dominant and non-dominant sites. The post-hoc analysis showed that within the non-birth control group, the HDR had significantly lower tibial SOS scores of bone strength when compared to the LDR but Aere were no significant differences found between the two dietary restraint groups for those currently on birth control. HDR had significantly lower levels of OC than LDR and the BC group had lower levels of BAP than the nBC group. Consistently, the follow-up analysis revealed that within those not on birth control, subjects who were classified as HDR had significantly (f*<0.05) lower levels of OC when compared with LDR but no significant differences were observed in bone turnover between the two dietary restraint groups for those currently on birth control. Physical activity was not correlated with SOS scores and bone turnover markers possibly due to the low physical activity variability in this group of women. Conclusion This is the first study to examine the effects of dietary restraint on bone strength and turnover among this population of women. The most important finding of this study was that bone strength and turnover are negatively influenced by dietary restraint independent of relative body fat. In general, the results of the present thesis suggest that dietary restraint, oral contraceptive use, as well as low daily calcium intake and low physical activity levels were widespread behaviours among this population of college-aged women. The young women who were using dietary restraint as a strategy to lose weight, and thus were in the HDR group, despite their higher relative body fat and weight, had lower scores of bone strength and lower levels of markers of bone turnover compared to the low dietary restrainers. Additionally, bone turnover seemed to be negatively affected by oral contraceptives, while bone strength, as assessed by QUS, seemed unaffected by their use in this population of young women. Physical activity (weekly energy expenditure), on the other hand, was not associated with either bone strength or bone tiimover possibly due to the low variability of this variable in this population of young Canadian women.

Preliminary epidemiological study of latent tuberculosis in Mexican agricultural workers in the Niagara region, Canada

It is well documented that the majority of Tuberculosis (TB) cases diagnosed in Canada are related to foreign-bom persons from TB high-burden countries. The Canadian seasonal agricultural workers program (SAWP) operating with Mexico allows migrant workers to enter the country with a temporary work permit for up to 8 months. Preiimnigration screening of these workers by both clinical examination and chest X-ray (CXR) reduces the risk of introducing cases of active pulmonary TB to Canada, but screening for latent TB (LTBI) is not routinely done. Studies carried out in industrialized nations with high immigration from TBendemic countries provide data of lifetime LTBI reactivation of around 10% but little is known about reactivation rates within TB-endemic countries where new infections (or reinfections) may be impossible to distinguish from reactivation. Migrant populations like the SAWP workers who spend considerable amounts of time in both Canada and TBendemic rural areas in Mexico are a unique population in terms of TB epidemiology. However, to our knowledge no studies have been undertaken to explore either the existence of LTBI among Mexican workers, the probability of reactivation or the workers' exposure to TB cases while back in their communities before returning the following season. Being aware of their LTBI status may help workers to exercise healthy behaviours to avoid TB reactivation and therefore continue to access the SAWP. In order to assess the prevalence of LTBI and associated risk factors among Mexican migrant workers a preliminary cross sectional study was designed to involve a convenience sample of the Niagara Region's Mexican workers in 2007. Research ethics clearance was granted by Brock University. Individual questionnaires were administered to collect socio-demographic and TB-related epidemiological data as well as TB knowledge and awareness levels. Cellular immunity to M tuberculosis was assessed by both an Interferon-y release assay (lGRA), QuantiFERON -TB Gold In-Tube (QFf™) and by the tuberculin skin test (TSn using Mantoux. A total of 82 Mexican workers (out of 125 invited) completed the study. Most participants were male (80%) and their age ranged from 22 to 65 years (mean 38.5). The prevalence of LTBI was 34% using TST and 18% using QFTTM. As previously reported, TST (using ~lOmm cut-off) showed a sensitivity of 93.3% and a specificity of 79.1 %. These findings at the moment cannot predict the probability of progression to active TB; only longitudinal cohort studies of this population can ascertain this outcome. However, based on recent publications, lORA positive individuals may have up to 14% probability of reactivation within the next two years. Although according to the SA WP guidelines, all workers undergo TB screening before entering or re-entering Canada, CXR examination requirements showed to be inconsistent for this population: whereas 100% of the workers coming to Canada for the first time reported having the procedure done, only 31 % of returning participants reported having had a CXR in the past year. None of the participants reported ever having a CXR compatible with TB which was consistent with the fact that none had ever been diagnosed with active pulmonary TB and with only 3.6% reporting close contact with a person with active TB in their lifetime. Although Mexico reports that 99% of popUlation is fully immunized against TB within the first year of age, only 85.3% of participants reported receiving BOC vaccine in childhood. Conversely, even when TST is not part of the routine TB screening in endemic countries, a suqDrisingly high 25.6% reported receiving a TST in the past. In regards to TB knowledge and awareness, 74% of the studied population had previous knowledge about (active) TB, 42% correctly identified active TB symptomatology, 4.8% identified the correct route of transmission, 4.8% knew about the existence of LTBI, 3.6% knew that latent TB could reactivate and 48% recognized TB as treatable and curable. Of all variables explored as potential risk factors for LTBI, age was the only one which showed statistical significance. Significant associations could not be proven for other known variables (such as sex, TB contact, history of TB) probably because of the small sample size and the homogeneity of the sample. Screening for LTBI by TST (high sensitivity) followed by confirmation with QFT''"'^ (high specificity) suggests to be a good strategy especially for immigrants from TB high-burden countries. After educational sessions, workers positive for LTBI gained greater knowledge about the signs and symptoms of TB reactivation as well as the risk factors commonly associated with reactivation. Additionally, they were more likely to attend their annual health check up and request a CXR exam to monitor for TB reactivation.

Aerobic exercise in adolescence : self-efficacy and stage of change

The purpose of this cross-sectional exploratory study was to examine the relationships among self-efficacy, stage of change, and exercise behaviour in a sample of younger (Grade 9) and older (Grade 12) adolescents. A secondary objective of this study was to apply the transtheoretical model of Stage of Change, as a measure of intention to change, in order to discover the applicability of the model to an adolescent cohort in relation to exercise behaviour. This five-stage model is a self-report measure of an individual's readiness to adopt a new behaviour (e.g., regular exercise). The transtheoretical model incorporates Bandura's self-efficacy factor, which is purported to be a predictive measure of exercise behaviour and a covariant of stage. Exercise behaviour was measured with the Physical Activity Scale, and the University of Rhode Island Change Assessment Scale (URleA) was used to measure the stage of change and self-efficacy variables. The results of this study indicated significant differences between younger and older adolescents, and between males and females in their exercise behaviour. No significant differences were found for grade and gender on stage of change as measured by either a single-item question or a continuous measure of stage. Although grade and gender subgroups were not significantly different in their self-efficacy, significant interaction was found in the grade*gender variable.

Mating behaviours of the field cricket (Gryllus integer) at different levels of male density

The reproductive behaviour of the field cricket, Gryllus integer, was systematically observed in indoor arenas to determine the extent of female Choice and male-male competition at different sex ratios representing two male densities (12:6 and 6:6). The costs and benefits to males and females in those two densities were analyzed according to the theory of the evolution o£ leks. Observations were conducted during the dark hours when most calling occurred since hourly rates of courtship song and mating did not fluctuate significantly over a 24 h period. Female mating rates were not significantly different between densities, therefore males at high densities were not advantaged because of increased female tendencies to mate when social stimulation was increased. Mean rates of acoustical signalling (calling and courtin"g) did not differ significantly between densities. Mean rates of fighting by males at the high density were significantly greater than those of males at the low density. Mating benefits associated with callin~courting and fighting were measured. Mating rates did not vary with rates of calling at either density. Calling was not a prerequisite to mating. Courtship song preceded all matings. There was a significant power fit between male mating and courting rates, and male mating and fighting rates at the low, but not at the high, density. Density differences in the benefits associated with increased courting and fighting may relate, in part, to greater economic defensibility and monopoly of females due to reduced male competition at the low density. Dominant males may be preferentially chosen by females or better able to monopolize mating opportunities than subordinate males. Three criteria were used to determine whether dominant males were preferentially chosen by females. The number of matings by males who won fights (within 30 min of mating) was significantly greater than the number of matings by males who were defeated in such fights. Mating rates did not vary significantly with rates of winning at either density. There was a significant power fit between male mating rates and the percentage of fights a male won (irrespective of his fighting-frequency) at the low density. The mean duration a male guarded the female after mating did not vary significantly between densities. There was a significant linear relationship between the duration a spermatophore was retained and the duration a male guarded the female after mating. Courtship song apparently stimulated spermatophore removal. Male guarding involved inter-male aggression and reduced courtship attempts by other males. Males at the high density received no apparent reproductive benefits associated with increased social stimulation. Conclusive evidence for preferential choice of males by females, using the criteria examined here, is lacking. Males at the lower density had fewer competitors and could monopolize females more effectively.

Risk-taking behaviours in adolescent boys and girls : sexuality and dietary health

This study examined adolescents' reported sexual and dietary health-risk behaviours and perceptions. Specifically, this study analyzed the data of 600 students (300 male~ 300 female) in grades 9, I 1, and OAC (mean, standard deviation). The mean age of the students in the sample is 16 with a standard deviation of 1.6. The study was a secondary analysis ofthe first-year data of a 3-year longitudinal study conducted by Youth Lifestyle Choices-Community University Research Alliance (YLC-CURA) on adolescents. To explore sexuality and dietary health, this study purposefully selected sections of the survey that represented sex and dieting behaviours of adolescents. Separate gender and age data analyses revealed different patterns among the variables. Specifically., findings revealed that adolescents who engaged in recent sexual activities were more likely to have a relatively more positive body image perception and were relatively more likely to engage in disordered eating. Across both genders and 3 age levels, adolescents reported that despite their unhealthy dietary habits they felt that dieting was not a high-risk behaviour. Results were discussed in terms of educational implication for sexual health programs.

The evaluation of a predialysis class on client knowledge and attitude toward compliant behaviours

In this quasi-experimental study, the theory of reasoned action was used as a conceptual framework to assess the outcome effect of a predialysis class. A pretest, posttest design was used to determine changes in client knowledge about their condition and its treatment, and their intention, attitudes and social norm towards compliant behaviours. The related compliant behaviours were following a low-salt diet and taking medications as proscribed. Thirty-eight End Stage Renal Diseases (ESRD) clients were self-selected into the treatment or control groups. Both groups received the standard predialysis education from members of the multidisciplinary renal team. In addition, the treatment group also attended the predialysis class. Subjects' health locus of control, anxiety and demographic variables were measured as possible extraneous variables. Study subjects from both groups demonstrated a high internal and powerful others health locus of control and a normal range of anxiety. Although not statistically significant ill = .64), the experimental group demonstrated higher knowledge level and greater intention to follow a low salt diet UL= .73). They developed more significantly positive attitudes towards following a low salt diet and increased subjective norm influence after attending the predialysis class. Attending the predialysis class did not have an effect on subjects' intentions, attitudes or subjective norm towards taking medications as prescribed. Conclusion: The predialysis class was only marginally effective in increasing client knowledge, but influenced clients' attitudes towards following a low-salt diet. Based on the results, recommendations for improvements to the class have been suggested.