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Background: It is widely known that a proportion of university students use drugs. However, much less is known about how they source and supply their drugs. Objectives: In this article, we investigate student drug trading activity, including how they obtained their drugs, whether they sold drugs, and the extent to which their drug trading might be described as a form of “social supply”. Methods: A survey was conducted of all students across seven of the nine universities of Wales. In total, 7855 students submitted a questionnaire and 1877 of these reported drug use in the current academic year. All students who reported using one or more illegal drugs in the current academic year were asked how they obtained their drugs, how they funded their drug use, whether they had sold, traded or given away illegal drugs, along with their motives for drug trading. Results: The results showed that about half of users obtained drugs solely from friends and associates and one-fifth obtained them solely from external dealers. One-quarter used friends and associates as well as external markets. In many cases, supplying drugs amounted to sharing them or giving them away. However, over one-third of students said that they had sold drugs. Conclusions: Overall, the methods of sourcing and supplying drug among university students shares features of both “social supply” and “traditional” drug markets. We conclude that the student drug market investigated is best described as a “hybrid” combination of both.  相似文献   
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ABSTRACT

Forest workers, including loggers, foresters, and wildland firefighters, are regularly exposed to some of the most fatal occupational environments in the United States. These hazardous work environments may become even more complex and dynamic when subject to bark beetle outbreaks that have resulted in significant tree mortality. The impacts of tree death from bark beetles are significant, with the cumulative 17-year (2000–2016) footprint for bark beetle caused tree mortality estimated at 54 million acres. However, how workers think about and act in these environments is understudied. This study, therefore, approaches the issue of beetle kill and forest worker safety by examining the perspectives or workers themselves. Its contribution is to leverage ethnographic research to provide insights that can generate new research questions, better inform outreach, and ultimately improve worker safety outcomes. The resulting insights show that beetle kill was understood by workers as a hazard that increased the complexity and dynamism of the work environment, making situational awareness both more necessary and more difficult to maintain. While much research about situational awareness focuses on hazardous situations, it is suggested that building adequate situational awareness should also include broader considerations of organizational communication, as well as training and experience considered over the course of entire careers.  相似文献   
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PurposePhysician burnout is reported in more than one out of every 2 practicing clinicians and is just as prevalent in training physicians. Burnout severity is also associated with increasing levels of financial debt. Medical professionals are notable for their high and increasing levels of debt; despite this, financial literacy is poor among physicians, and financial education is largely absent from medical education. Radiation oncologists (ROs) are no different in this regard, with 33% of residents reporting high levels of burnout symptoms, 33% carrying >$200,000 of educational debt, and 75% reporting being unprepared to handle future financial decisions. To fill this gap, we reviewed the basic tenets of personal financial health for the early career RO.Methods and materialsThe core concept of financial independence (FI) is introduced, and we review 4 basic tenets of personal financial health for the young medical professional: debt, behavior, investment, and asset protection strategies.ResultsFI is achieved by saving until the desired quality of life can be maintained, independent of employment income. Debt strategy involves minimizing debt accrual, understanding student loans, and having a debt management plan. Behavioral strategy involves setting financial goals, calculating worth and a savings rate, budgeting, and frugal living. The basics of investing include asset allocation, diversification, rebalancing, and minimizing expenses. Finally, asset protection includes insuring against catastrophic events with disability, life, health, liability, and property insurance.ConclusionsHealthy financial practices can lead to FI and may facilitate professional and personal freedoms with the goal of mitigating burnout-associated stressors. The tenets of strong financial health for ROs in the early stages of their career include sound debt, behavioral, investment, and asset protection strategies. Furthermore, initial and continuing financial education is an overlooked but important curriculum component. ROs with their financial houses in order can devote more resources to learning and practicing good medicine while living healthy, rewarding lives.  相似文献   
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Preventing sports injury has rarely been cited as an appropriate action to respond to the obesity epidemic, and in fact a recent letter has suggested that those playing sport are as responsible for their predicament as those who are obese. This opinion piece argues that it is time for better prevention and management of sports injury to be seen as part of the complex solution to preventing obesity, rather than being a self-inflicted problem that governments should continue to ignore.  相似文献   
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Central dopamine function is reduced by decreasing the availability of the catecholamine precursor, tyrosine, using a tyrosine-free amino acid mixture containing multiple large neutral as well as branched chain amino-acids, which compete with tyrosine for uptake into the brain. Current mixtures are cumbersome to make and administer, and unpalatable to patients and volunteers. Here, we investigate whether individual or limited amino-acid combinations could reduce brain tyrosine levels and hence dopamine function. Measurements of regional brain tyrosine levels, catecholamine and indoleamine synthesis (L-DOPA and 5-HTP accumulation, respectively) were used to identify an effective paradigm to test in neurochemical, behavioral and fos immunocytochemical models. Administration of leucine or isoleucine, or a mixture of leucine, isoleucine, and valine reduced tyrosine and 5-HTP, but not L-DOPA accumulation. A mixture of leucine, valine, and isoleucine supplemented with tryptophan reduced brain tyrosine and L-DOPA, but not 5-HTP. In microdialysis experiments this amino-acid mixture reduced basal and amphetamine-evoked striatal dopamine release, as well as amphetamine-induced hyperactivity. This mixture also reduced amphetamine-induced fos expression in striatal areas. In conclusion, the present study identified a small combination of amino acids that reduces brain tyrosine and dopamine function in a manner similar to mixtures of multiple amino acids. This minimal mixture may have use as a dopamine reducing paradigm in patient and volunteer studies.  相似文献   
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