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The effect of seat belt legislation on self-reported seat belt use among male and female college students was investigated. Questionnaires inquiring about seat belt use were administered to college students on three separate occasions: (i) two months prior to the time a mandatory seat belt law went into effect, (ii) two months after the law went into effect, and (iii) 16 months after the law went into effect. Reported seat belt use increased significantly for male and female college students two months after the law took effect. At 16 months postlaw, reported seat belt use remained high for female students but declined almost to the prelaw level for males. Possible reasons offered for these findings are that male college students may be more resistant to having their behavior regulated and, therefore, less likely to internalize changes forced on them, and college-age males may be more inclined to engage in risk-taking behavior than college-age females. The importance of considering males and females separately with respect to seat belt use and interventions designed to increase seat belt use is discussed.  相似文献   
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Many lotic fish species use natural patterns of variation in discharge and temperature as spawning cues, and these natural patterns are often altered by river regulation. The effects of spring discharge and water temperature variation on the spawning of shovelnose sturgeon Scaphirhynchus platorynchus have not been well documented. From 2006 through 2009, we had the opportunity to study the effects of experimental discharge levels on shovelnose sturgeon spawning in the lower Marias River, a regulated tributary to the Missouri River in Montana. In 2006, shovelnose sturgeon spawned in the Marias River in conjunction with the ascending, peak (134 m3/s) and descending portions of the spring hydrograph and water temperatures from 16 °C to 19 °C. In 2008, shovelnose sturgeon spawned in conjunction with the peak (118 m3/s) and descending portions of the spring hydrograph and during a prolonged period of increased discharge (28–39 m3/s), coupled with water temperatures from 11 °C to 23 °C in the lower Marias River. No evidence of shovelnose sturgeon spawning was documented in the lower Marias River in 2007 or 2009 when discharge remained low (14 and 20 m3/s) despite water temperatures suitable and optimal (12 °C?24 °C) for shovelnose sturgeon embryo development. A similar relationship between shovelnose sturgeon spawning and discharge was observed in the Teton River. These data suggest that discharge must reach a threshold level (28 m3/s) and should be coupled with water temperatures suitable (12 °C?24 °C) or optimal (16 °C?20 °C) for shovelnose sturgeon embryo development to provide a spawning cue for shovelnose sturgeon in the lower Marias River. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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The effects of repeated amphetamine (AMPH) pretreatment on norepinephrine (NE) neurotransmission in the hypothalamus and hippocampus were assessed using in vivo microdialysis. Rats were pretreated with either saline or an escalating-dose AMPH regimen (1-->10 mg/kg) over 10 consecutive days, and then were withdrawn from AMPH for either 1 day or 30 days, at which time the animals underwent two consecutive days of testing. As expected, repeated treatment with AMPH resulted in time-dependent changes in both spontaneous locomotor activity and in the psychomotor response to a subsequent challenge injection of AMPH. In addition, repeated exposure to AMPH resulted in time-dependent and regionally-specific changes in the basal concentrations of NE in dialysate, and in the NE response to an AMPH challenge. For example, AMPH pretreatment produced a persistent (at least one month) increase in the basal concentration of NE in the hippocampus, but not the hypothalamus, although the response to an AMPH challenge was altered in both structures. It is suggested that AMPH treatment produces adaptations in NE systems that far outlast the acute effects of the drug, and that these may contribute to both transient and more persistent behavioral sequelae associated with the discontinuation of chronic AMPH use.  相似文献   
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We study the evolution of telecommunications technology and the challenges to surveillance faced by law enforcement agencies. We focus on surveillance history in the United States. US government surveillance will have an increasing impact on the global civil society because of the globalization of packet-based communication networks-as a great deal of international traffic travels across American network wires. The bandwidth exchanges operating on the coasts of the US illustrate that surveillance policies in the U.S. will affect citizens in Pacific Rim and European communities. Policy makers must take a broader view of law enforcement surveillance and do more to ensure individual privacy  相似文献   
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OBJECTIVES: Giant gastric and duodenal ulcers (>2-3 cm in greatest dimension) are reported to have higher rates of complication and mortality and to be associated with increasing age, renal failure, and use of nonsteroidal antiinflammatory drugs (NSAIDs). This study investigated the outcome and associations of gastric and duodenal ulcers >2.5 cm compared to ulcers of lesser size. METHODS: Records from all patients with gastric and duodenal ulcers >0.5 cm diagnosed by upper endoscopy between January 1994 and September 1995 were studied for evidence of concurrent use of aspirin, NSAIDs, methamphetamine, and cocaine, as well as for transfusion requirements, length of hospital stay, mortality, surgery, rebleeding, Helicobacter pylori infection, and malignancy. RESULTS: A logistic regression analysis of the 220 patients identified revealed that recent methamphetamine and/or cocaine use was significantly predictive of giant ulcer formation (p = 0.0002) with an odds ratio of 9.66. Also significant was younger age (p = 0.026) and aspirin or NSAID use (p = 0.046). H. pylori infection was significant only for giant gastric ulcers (p = 0.031). Ulcer size did not predict mortality, rate of rebleeding, requirement for surgery, transfusion requirements, or length of hospital stay. However, giant gastric ulcers were significantly more likely to be malignant (p = 0.002). CONCLUSIONS: Giant gastric and duodenal ulcers were strongly associated with stimulant abuse. They were also associated with younger age and use of aspirin or NSAIDs. Additionally, giant gastric ulcers were associated with malignancy and H. pylori infection. Ulcer size did not predict rate of complications or outcome.  相似文献   
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A low-programmed-resistance low-thermal-budget, high-performance metal/silicide antifuse is reported. The programmed ON-State resistance of the metal/silicide antifuse is around 60 Ω, which is a factor of 10 less than that of Si-based antifuses (poly/n+ and poly/poly). Metal/silicide antifuses also eliminate the nonlinear ON-state resistance seen in Si-based antifuses. Programming of the antifuse can be done in 2 ms at 14 V, which is comparable to Si-based antifuses. Both ON- and OFF-state reliability of the metal/silicide antifuse are shown to be satisfactory  相似文献   
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OBJECTIVE: To explore the feasibility of recruiting, training, and placing in the field volunteers to assist community practices in enhancing the provision of preventive care. DESIGN: A case series design followed up a cohort of volunteers prospectively as they were recruited, trained, and assigned to practices. SETTING: The New Hampshire Division of the American Cancer Society recruited and trained the volunteer facilitators. INTERVENTION: Assistance from the volunteers in implementing a preventive services office system served as the intervention for practices. Volunteers were trained and supported by professional staff and an implementation manual. MAIN OUTCOME MEASURES: Recruitment, training, and volunteer experiences in working with practices, as well as the costs of supporting the program, were assessed. RESULTS: Twenty-six volunteers were trained. Of the 15 assigned to practices, 11 had begun to assist their assigned practices to establish a preventive services office system. Extensive planning, patience, and support were required. CONCLUSION: Volunteers recruited and supported by an intermediary organization can provide assistance to practices in implementing a preventive services office system.  相似文献   
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