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131.
Transferring research from the laboratory to mainstream applications requires the convergence of people, knowledge, and conventions from divergent disciplines. Solutions involve more than combining functional requirements and creative novelty. To transform technical capabilities of emerging mixed reality (MR) technology into the mainstream involves the integration and evolution of unproven systems. For example, real-world applications require complex scenarios (a content issue) involving an efficient iterative pipeline (a production issue) and driving the design of a story engine (a technical issue) that provides an adaptive experience with an after-action review process (a business issue). This article describes how a multi-disciplinary research team transformed core MR technology and methods into diverse urban terrain applications. These applications are used for military training and situational awareness, as well as for community learning to significantly increase the entertainment, educational, and satisfaction levels of existing experiences in public venues.  相似文献   
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Cerebral glucose utilization was higher during the first positron emission tomography (PET) session than during the second session, as assayed using the PET [18F]fluorodeoxyglucose method in male human volunteers. This difference was due largely to data from subjects with low-trait anxiety, since subjects with high anxiety showed similar metabolism in both PET sessions. High-anxiety subjects showed greater right/ left ratios of cerebral metabolism than low-anxiety subjects, particularly during the second PET session. These findings suggest that the level of anxiety may be an important variable to consider in PET studies using multiple sessions.  相似文献   
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Investigated potential factors related to the ability to detect deceit, including characteristics of the credibility assessor (e.g., personality, handedness, cue use), characteristics of the target (attractiveness, gender), and the modality of the report (audio-visual vs audio-only). 310 undergraduate students (aged 18-43 yrs) judged the honesty of 8 reports of emotionally laden events (true reports and 4 motivated lies) presented in audio-visual or audio-only formats. Results indicate that detection accuracy was significantly higher when the judge was left-handed, the target was unattractive, and the target and judge were of opposite genders. Judges most frequently relied on cues related to the content of the report to decide credibility, but the use of such cues was associated with lower detection accuracy. In contrast, although facial cues were relied upon less often, they were positively associated with accuracy. Implications for the process of credibility assessment are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A new measure has been developed to assess depressive symptoms, the Beck Depression Inventory for Youth (BDI-Y; J. S. Beck, A. T. Beck, & J. B. Jolly, 2001). This research extends previous validation research of BDI-Y total scores by examining internal consistency and convergent and predictive validity within a school-based sample (n = 859) of girls 9-13 years old by age level and for selected races or ethnic groups. Scores had high internal consistency, and there was support for using the BDI-Y to assess depressive symptoms. Reliability was slightly lower for 9-year-olds, but reliability and validity estimates did not differ by race or ethnic group. Finally, confirmatory factor analysis results provide some support for unidimensionality of scores but also point toward possible refinements. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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An analytical design methodology for continuous-time (CT) bandpass (BP) /spl Sigma//spl Delta/ modulators is presented. Second- and fourth-order tunable continuous time BP /spl Sigma//spl Delta/ modulator design equations are presented. A novel /spl Sigma//spl Delta/ loop architecture, where the traditional CT BP loop filter function is replaced with the filter function with fractional delays, is proposed. Validity of the methodology is confirmed by mixed-signal behavioral simulations.  相似文献   
140.
OBJECTIVE: To assess bone mineral density and body composition in postmenopausal women with primary hyperparathyroidism. DESIGN: Cross-sectional study with an age-matched control group. SETTING: University teaching hospital. PATIENTS: 41 postmenopausal women with mild primary hyperparathyroidism and 43 eucalcemic, age-matched controls. MEASUREMENTS: Total body, lumbar spine, and proximal femoral (femoral neck, Ward's triangle, and trochanter) bone mineral density; body composition; and fat distribution were measured using dual-energy x-ray absorptiometry. RESULTS: Women with primary hyperparathyroidism were heavier (75.5 kg compared with 66.3 kg; difference, 9.2 kg [95% CI, 3.7 to 14.7 kg]; P = 0.002), had a higher fat mass (33.3 kg compared with 26.1 kg; difference, 7.2 kg [CI, 3.0 to 11.4 kg]; P = 0.001), and had a more android pattern of fat distribution (android-to-gynoid fat ratio, 1.05 compared with 0.84; difference, 0.21 [CI, 0.1 to 0.32]; P = 0.0004) than the controls. Unadjusted bone mineral density was similar in patients and controls at all sites: total body, 0.990 compared with 1.023 g/cm2 (difference, 0.033; CI, -0.004 to 0.070); posteroanterior lumbar spine, 1.032 compared with 1.018 g/cm2 (difference, 0.014; CI, -0.031 to 0.059); lateral lumbar spine, 0.569 compared with 0.528 g/cm2 (difference, 0.041; CI, -0.022 to 0.104); femoral neck, 0.799 compared with 0.825 g/cm2 (difference, 0.026; CI, -0.072 to 0.124); Ward's triangle, 0.653 compared with 0.677 g/cm2 (difference, 0.024; CI, -0.035 to 0.089); trochanter, 0.734 compared with 0.733 g/cm2 (difference, 0.001; CI, -0.024 to 0.026); and arms, 0.720 compared with 0.739 g/cm2 (difference, 0.019; CI, -0.015 to 0.053). After adjustment for body weight, bone mineral density in women with primary hyperparathyroidism was lower than that in controls for total body (P = 0.0004), femoral neck (P = 0.001), Ward's triangle (P = 0.01), trochanter (P = 0.02), and arms (P = 0.0006). Spinal bone mineral density did not differ between groups. CONCLUSIONS: Body weight, total body fat mass, and proportion of android fat are increased in postmenopausal women with primary hyperparathyroidism; these unexplained factors may be relevant to the increased incidence of cardiovascular disease in this condition. Unadjusted bone mineral density values are similar in patients with primary hyperparathyroidism and in controls, suggesting that this condition is not associated with an increased risk for fracture.  相似文献   
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