United States Department of the Army

About: United States Department of the Army is a government organization based out in Arlington, Virginia, United States. It is known for research contribution in the topics: Poison control & Population. The organization has 32668 authors who have published 42453 publications receiving 947075 citations. The organization is also known as: DA & U.S. Department of the Army.

Effects of aerobic exercise on mild cognitive impairment: a controlled trial.

Abstract: Objectives To examine the effects of aerobic exercise on cognition and other biomarkers associated with Alzheimer disease pathology for older adults with mild cognitive impairment, and assess the role of sex as a predictor of response. Design Six-month, randomized, controlled, clinical trial. Setting Veterans Affairs Puget Sound Health Care System clinical research unit. Participants Thirty-three adults (17 women) with amnestic mild cognitive impairment ranging in age from 55 to 85 years (mean age, 70 years). Intervention Participants were randomized either to a high-intensity aerobic exercise or stretching control group. The aerobic group exercised under the supervision of a fitness trainer at 75% to 85% of heart rate reserve for 45 to 60 min/d, 4 d/wk for 6 months. The control group carried out supervised stretching activities according to the same schedule but maintained their heart rate at or below 50% of their heart rate reserve. Before and after the study, glucometabolic and treadmill tests were performed and fat distribution was assessed using dual-energy x-ray absorptiometry. At baseline, month 3, and month 6, blood was collected for assay and cognitive tests were administered. Main Outcome Measures Performance measures on Symbol-Digit Modalities, Verbal Fluency, Stroop, Trails B, Task Switching, Story Recall, and List Learning. Fasting plasma levels of insulin, cortisol, brain-derived neurotrophic factor, insulinlike growth factor-I, and β-amyloids 40 and 42. Results Six months of high-intensity aerobic exercise had sex-specific effects on cognition, glucose metabolism, and hypothalamic-pituitary-adrenal axis and trophic activity despite comparable gains in cardiorespiratory fitness and body fat reduction. For women, aerobic exercise improved performance on multiple tests of executive function, increased glucose disposal during the metabolic clamp, and reduced fasting plasma levels of insulin, cortisol, and brain-derived neurotrophic factor. For men, aerobic exercise increased plasma levels of insulinlike growth factor I and had a favorable effect only on Trails B performance. Conclusions This study provides support, using rigorous controlled methodology, for a potent nonpharmacologic intervention that improves executive control processes for older women at high risk of cognitive decline. Moreover, our results suggest that a sex bias in cognitive response may relate to sex-based differences in glucometabolic and hypothalamic-pituitary-adrenal axis responses to aerobic exercise.

Increased plasma and platelet to red blood cell ratios improves outcome in 466 massively transfused civilian trauma patients

Abstract: Objective:To determine the effect of blood component ratios in massive transfusion (MT), we hypothesized that increased use of plasma and platelet to red blood cell (RBC) ratios would result in decreased early hemorrhagic death and this benefit would be sustained over the ensuing hospitalization.Sum

Climate as a moderator of the relationship between leader-member exchange and content specific citizenship: safety climate as an exemplar.

Abstract: The present study integrates role theory, social exchange, organizational citizenship, and climate research to suggest that employees will reciprocate implied obligations of leadership-based social exchange (e.g., leader-member exchange [LMX]) by expanding their role and behaving in ways consistent with contextual behavioral expectations (e.g., work group climate). Using safety climate as an exemplar, the authors found that the relationship between LMX and subordinate safety citizenship role definitions was moderated by safety climate. In summary, high-quality LMX relationships resulted in expanded safety citizenship role definitions when there was a positive safety climate and there was no such expansion under less positive safety climates. The authors also found that safety citizenship role definitions were significantly related to safety citizenship behavior. Implications for both social exchange theory and safety research are discussed.

Combat wounds in operation Iraqi Freedom and operation Enduring Freedom

Abstract: BACKGROUND: There have been no large cohort reports detailing the wounding patterns and mechanisms in the current conflicts in Iraq and Afghanistan. METHODS: The Joint Theater Trauma Registry was queried for all US service members receiving treatment for wounds (International Classification of Diseases-9th Rev. codes 800-960) sustained in Operation Iraqi Freedom and Operation Enduring Freedom from October 2001 through January 2005. Returned-to-duty and nonbattle injuries were excluded from final analysis. RESULTS: This query resulted in 3,102 casualties, of which 31% were classified as nonbattle injuries and 18% were returned-to-duty within 72 hours. A total of 1,566 combatants sustained 6,609 combat wounds. The locations of these wounds were as follows: head (8%), eyes (6%), ears (3%), face (10%), neck (3%), thorax (6%), abdomen (11%), and extremity (54%). The proportion of head and neck wounds is higher (p < 0.0001) than the proportion experienced in World War II, Korea, and Vietnam wars (16%-21%). The proportion of thoracic wounds is a decrease (p < 0.0001) from World War II and Vietnam (13%). The proportion of gunshot wounds was 18%, whereas the proportion sustained from explosions was 78%. CONCLUSIONS: The wounding patterns currently seen in Iraq and Afghanistan resemble the patterns from previous conflicts, with some notable exceptions: a greater proportion of head and neck wounds, and a lower proportion of thoracic wounds. An explosive mechanism accounted for 78% of injuries, which is the highest proportion seen in any large-scale conflict. Language: en

High-performance carbon nanotube fiber.

Abstract: With their impressive individual properties, carbon nanotubes should form high-performance fibers. We explored the roles of nanotube length and structure, fiber density, and nanotube orientation in achieving optimum mechanical properties. We found that carbon nanotube fiber, spun directly and continuously from gas phase as an aerogel, combines high strength and high stiffness (axial elastic modulus), with an energy to breakage (toughness) considerably greater than that of any commercial high-strength fiber. Different levels of carbon nanotube orientation, fiber density, and mechanical properties can be achieved by drawing the aerogel at various winding rates. The mechanical data obtained demonstrate the considerable potential of carbon nanotube assemblies in the quest for maximal mechanical performance. The statistical aspects of the mechanical data reveal the deleterious effect of defects and indicate strategies for future work.