Evidence suggests that adolescence and young adulthood is a transitional stage whereby unique contextual factors may increase the likelihood for certain individuals to engage in risk-taking compared to their peers. In addition to influential environmental aspects (i.e. parenting, societal affiliations, peer influence) an adolescent’s and young adult’s underdeveloped cognitive control system is unable to successfully inhibit early maturing tendencies such as sensation seeking and reward sensitivity. However, previous research indicates that certain parental mechanisms may serve as protective/promotive agents for stabilizing this neurobiological imbalance. Therefore, the focus of the current research was to examine how parenting behaviors and styles moderate the relations between neurobiological variables and risk-taking during young adulthood. It was expected that authoritarian parenting methods would have adverse effects on young adult behavior by inhibiting maturing cognitive control abilities and exacerbating early developing socioemotional tendencies. Conversely, it was suspected that authoritative parenting would serve as a protective agent against young adult risk-taking by increasing cognitive control abilities and suppressing socioemotional tendencies. Additionally, parental monitoring is a behavior that, depending on context, may serve to either inhibit or exacerbate young adult risk-taking. An online survey was conducted to assess young adults from MTurk. Participants completed a variety of questionnaires regarding parent-child interactions, levels of sensation seeking and self-regulatory abilities, and engagement in risky behavior such as alcohol abuse. In sum, this research may be used to inform parents and caregivers of the influence of parent-child interactions on adolescent and young adult risk-taking.

Adolescence and young adulthood are the periods of development associated with the highest amount of risk-taking. One theory, the Dual-Systems model, suggests that this could be due to an imbalance in the maturation of two brain systems: reward appraisal, which matures first, and cognitive control, which matures later. This imbalance may be the cause of adolescents’ tendency to favor immediate rewards, disregarding consequences. Depressed adolescents, however, behave differently. While it is not exactly clear whether they take more risks or fewer risks, depressed adolescents display different interactions and decision making with their peers than non-depressed adolescents. This study attempted to use these patterns of behavior already identified in previous research to predict where an adolescent would fall on a depression continuum based on their Self-Focused and Other-Focused risk behaviors. Results did not find a link between depression and either type of risk. Results may be inconclusive due to issues within the data and data collection process.

通路商在「供應鏈」的角色，除了必須發揮原廠與客戶端中間橋樑之基本功能以外，尚須面對外部競爭及內部營運績效提昇之考驗。在面臨內外在環境的衝擊及市場的激烈競爭，通路商如何發展其競爭策略來厚植其競爭力，謀求生存利基，是一值得探討的問題。 本研究主要目的是在探討台灣半導體通路商之發展策略，透過對於國內有效問卷之180家通路商作分析，經有系統的收集與整理資料後，利用隨機效果的橫斷時間序列資料迴歸模式分析，結果顯示： 一、組織績效正差會增加通路商對於新產品與新客戶開發的發展策略。 二、組織績效負差會增加通路商對於新產品開發的發展策略，但減少新客戶開發。。 三、領導者的認知度需求度對於新產品與新客戶開發的發展策略有負向影響。 四、領導者的冒險傾向對於新產品與新客戶開發的發展策略有正向影響。 五、領導者的認知需求度對於績效差與新產品開發有調節效果。 六、領導者的冒險傾向對於績效差與新產品開發有調節效果。 / The role of distributor, basically, not only supply chain management but also “bridge” between suppliers and customers, Meanwhile, they encounter external competition as well as challenge of internal performance improvement. Beset by difficulties both at home and abroad as well as fierce competition, distributors need to modify their competition strategies in order to enhance their competitiveness and chip in the niche category they can rely on. It is worthwhile to understand how the semiconductor distributors in Taiwan keep their competitive capability under the challengeable situations. The aim of this study is to investigate the development strategy of Taiwanese small and medium distributors who exclusively manage semiconductor products. After the collection of 180 leader-company dyadic data, this study utilized the random-effects panel regression models to examine the hypotheses. The results showed： 1. The positive difference between organizational performance and past performance increased distributors’ development strategies of new product and new customer exploration. 2. The negative difference between organizational performance and past performance increased distributors’ development strategies of new product exploration but decrease new customer exploration. 3. Top leaders’ need for cognition had negative effect on both of new product and new customer exploration of development strategy. 4. Top leaders’ risk-taking propensity had positive effect on both of new product and new customer exploration of development strategy. 5. The need for cognition of a top leader had moderating effects on the relationships between performance differences and new product development. 6. The risk-taking propensity of a top leader had moderating effects on the relationships between performance differences and new product development.

The overall aim of this thesis was to inestigate Swedish adolescents' perceptions and behaviours regarding sexual risk taking. Specific objectives were to explore teenagers' perceptions of contraceptive use, unintended pregnancy, and abortion; teenage girls' experiences of decision making process and support connected to abortion; and male adolescents' perceptions of sexual risk taking and barriers to practicing safe sex. Another objective was to evaluate the effect of advance provision of emergency contraceptive pills to teenage girls. The methodologies included focus group discussions, in-depth interviews, and a randomized controlled trial. Among the adolescents in our studies, teenage parenthood was generally viewed as a "catastrophe", and the majority expressed supportive attitudes towards abortion (studies I-IV). Occasions of failure to use contraceptives were common, especially when sex was unplanned (studies I-V). Pregnancy prevention was perceived as the woman's responsibility. However, many girls were reluctant about using homonal contraceptives due to worries about negative side effects (I, III). Initiating condom use was difficult for girls, as well as for boys, for a number of reasons (I-IV): fear of ruining an intimate situation, associations with disease, distrust, pleasure reduction, and (for the boys) the fear of loosing one's erection. Males generally perceived personal and partner-related risks connected to unprotected intercourse as low. Few males were worried that an unintended pregnancy would be carried to term, and the majority would urge the girl towards abortion if she seemed ambivalent (II, IV). Girls viewed the abortion decision as a natural, yet difficult choice, strongly influenced by attitudes of partners, parents, peers and societal norms (III). Teenage girls provided with emergency contraceptive pills in advance used it more frequently and sooner after unprotected intercourse compared with controls, without jeopardising regular contraceptive use (V).

Risk taking (RT) and self-harm (SH) are clinically, conceptually, and empiricallyrelated, yet separate constructs, which occur most frequently during adolescence. The current study utilized retrospective reports of college students to determine reported ages of engagement in RT and SH behaviors. Reported ages were compared with predictions for ages of high frequency engagement in RT based on the Dual Systems Model of Adolescent Risk Taking (DSMART; Steinberg, 2010). The sample consisted of 228 college students, ranging in age from 18 to 48 years (mean 22.8), who completed a survey of commonly investigated RT (12 items) and SH (18 items) behaviors. A positive correlation between the RT and SH scales supported a relationship between RT and SH, as predicted. The mean ages of engagement reported for both RT and SH behaviors were significantly higher than the ages predicted by the DSMART. However, the mean ages of engagement varied significantly by behavior grouping (RT, SH), and by subgroups within each behavior group. The NSSI subgroup of SH and the Situational subgroup of RT were noted to have the lowest mean age of high frequency engagement at the subgroup and behavior item level. A relationship between RT and SH was supported and information regarding ages of engagement in RT relative to ages of engagement in SH in the sample provided a further basis for understanding the emergence of these behaviors. The findings are discussed with regard to the DSMART and the relationship between RT and SH behaviors

Project (Ed.S.)--James Madison University, 2009. / Includes bibliographical references.

As international travel is rapidly increasing, more people are being exposed to potentially more antibiotic resistant bacteria, a changed infectious disease epidemiology, and an increased risk of accidents and crime. Research-based advice is needed to adequately inform travellers about these risks. We studied travellers who sought advice from the Travel Medicine Clinic at the Department of Infectious Diseases, Umeå University Hospital, as well as university students from Umeå, Stockholm, and Gothenburg travelling abroad for study, research, and clinical exchange programs. From retrospective data at the Travel Medicine Clinic, we found that pre-existing health problems were rare among travellers from Umeå seeking pre- travel health advice and vaccinations. In addition, we found that the travel destination and the sex of the traveller affected vaccination levels. Although hepatitis A is endemic to both Thailand and Turkey, compared to travellers to Thailand few travellers to Turkey visited the clinic for hepatitis A vaccination. The data also revealed that more women than men were vaccinated against Japanese encephalitis despite comparable trips. A prospective survey study showed that travellers felt that the pre-travel health advice they received was helpful. Two-thirds of the travellers followed the advice given although they still fell ill to the same extent as those who were not compliant with the advice. Factors outside the control of travellers likely affect the travel-related morbidity. Compared to older travellers, younger travellers were less compliant with advice, fell ill to a greater extent, and took greater risks during travel. In a prospective survey study, we found that healthcare students had higher illness rates and risk exposure when abroad compared to students from other disciplines. This difference was mainly due to the fact that healthcare students more often travelled to developing regions during their study period abroad. When abroad, half of all students increased their alcohol consumption and this was linked to an increased risk of theft and higher likelihood of meeting a new sex partner. The healthcare students participating in the survey study also submitted stool samples before and after travel. These samples were tested for the presence of antibiotic resistance, both by selective culturing for ESBL-PE (Extended-Spectrum Beta-Lactamase Producing Enterobacteriaceae) as well as by metagenomic sequencing. About one-third (35%) of the students became colonised by ESBL-PE following their study abroad. The strongest risk factor for colonisation was travel destination; for example, 70% of students who had travelled to India became colonised. Antibiotic treatment during travel was also a significant risk factor for colonisation. The stool samples from a subset of study subjects were analysed using metagenomic sequencing. From this we learned that although the majority of resistance genes in the gut microbiome remained unchanged following travel, several clinically important resistance genes increased, most prominently genes encoding resistance to sulphonamide, trimethoprim, and beta-lactams. Overall, taxonomic changes associated with travel were small but the proportion of Proteobacteria, which includes several clinically important bacteria (e.g., Enterobacteriaceae), increased in a majority of the study subjects. Clearly, there are risks associated with international travel and these risks include outside factors as well as the personal behaviour of travellers. We believe our results can be used to develop better pre-travel advice for tourists as well as university students studying abroad resulting in safer travel.

Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal

This thesis consists of an introductory part and four self-contained papers related to individual financial behavior and risk-taking in financial markets. In Paper [I] we estimate within-family and community social interaction effects upon an individual’s stock market entry, participation, and exit decision. Interestingly, community sentiment towards the stock market (based on portfolio outcomes in the community) does not influence individuals’ likelihood to enter, while a positive sentiment increases (decreases) the likelihood of participation (exit). Overall, the results stress the importance of accounting for family social influence and highlight potentially important differences between family and community effects in individuals’ stock market participation. In Paper [II] novel evidence is provided indicating that the influence from family (parents and partners) and peer social interaction on individuals’ stock market participation vary over different types of individuals. Results imply that individuals’ exposure to, and valuation of, stock market related social signals are of importance and thus, contribute to the understanding of the heterogeneous influence of social interaction. Overall, the results are interesting and enhance the understanding of the underlying mechanisms of social interaction on individuals’ financial decision making. In Paper [III] the impact of divorce ­­­on individual financial behavior is empirically examined in a dynamic setting. Evidence that divorcing individuals increase their saving rates before the divorce is presented. This may be seen as a response to the increase in background risk that divorce produces. After the divorce, a negative divorce effect on individual saving rates and risky asset shares are established, which may lead to disparities in wealth accumulation possibilities between married and divorced. Women are, on average, shown to not adjust their precautionary savings to the same extent as men before the divorce. I also provide tentative evidence that women reduce their financial risk-taking more than men after a divorce, which could be a result of inequalities in financial positions or an adjustment towards individual preferences.   Paper [IV] provides novel empirical evidence that gender identity is of importance for individuals’ financial risk-taking. Specifically, by use of matching and by dividing male and females into those with “traditional” versus “nontraditional” gender identities, comparison of average risk-taking between groupings indicate that over a third (about 35-40%) of the identified total gender risk differential is explained by differences in gender identities. Results further indicate that risky financial market participation is 19 percentage points higher in groups of women with nontraditional, compared with traditional, gender identities. The results, obtained while conditioning upon a vast number of controls, are robust towards a large number of alternative explanations and indicate that some individuals (mainly women) partly are fostered by society, through identity formation and socially constructed norms, to a relatively lower financial risk-taking.

The thesis deals with variation in age and size at maturation in Saduria entomon and Pontoporeia affinis along a depth gradient in the Gulf of Bothnia, Sweden. I have analysed at what sizes and ages animals should mature in relation to growth and mortality conditions. The thesis also deals with predator-prey interactions within and between the two species. The isopod Saduria entomon matured during winter at an age of three years at 5 m depth in the Norrby archipelago (63° 30'N, 19° 50'E). Males matured eariier and at larger sizes (27-48 mm) than females (23-36 mm). The offspring were released in early summer. The adult size increased with increasing depth. Outside the archipelago, at 125 m depth, the sexes reached a size of 84 and 54 mm respectively. No evidence for temporal restriction in the release of the young was found at the deep area. The species was shown to have a high capacity for cannibalism on small conspecifics, although the small ones have the potential to avoid aggregations of large conspecifics. The number of small conspecifics eaten was related both to the absolute and relative densities of the alternative prey Pontoporeia affinis. The cannibalistic behaviour have the potential to act as a stabilizing mechanism in the Saduria-Pontoporeia system. Fourhom sculpin (Myoxocephalus quadricornis) was the fish species of utmost importance as a predator on S.entomon, and it mainly preferred large specimens. The amphipod Pontoporeia affinis matured at an age of two years in the littoral zone and at a very deep (210 m) locality. Between these depths it mainly reached maturation at an age of three years. In some years in densely populated areas, they delayed reproduction another year and reproduced as four year old. The variation in age at maturation in P.affinis in relation to depth could be quantitatively predicted by maximizing fitness in the Euler-Lotka equation. The size variation at maturation in S.entomon could be qualitatively predicted by maximizing fitness in the Euler-Lotka equation. The general condition for a smaller size at maturity to be adaptive at high temperatures (i.e. shallow areas) is that mortality rate should increase faster than growth rate with increasing temperature. When mortality is higher in young stages than in older and larger ones the pattern is also predicted when growth increases faster than mortality. Small animals may prefer warmer habitats than large ones, because of the presence of a size dependent trade-off between temperature induced growth and mortality. More exactly, the optimum solution of the trade-off between growth and mortality in hazardous environments was suggested to approach maximization of the expression s(W+g)/W, where s is survival rate, W is body weight, and g is growth rate. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1990, härtill 6 uppsatser</p> / digitalisering@umu