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Sixty-nine patients, aged 63-98 years and admitted at the Geneva Geriatric Hospital, were included in the present retrospective study. They received clomipramine orally, 50 or 75 mg/day. Blood concentrations of clomipramine were measured as part of a routine drug monitoring program. Comparison with a reference population of patients aged < or = 65 years indicated that elderly patients with concomitant somatic diseases reach higher dose-normalized concentrations of clomipramine and increased parent drug to demethylated metabolite ratios, as a consequence of impaired demethylation (approximately 50%) and hydroxylation (approximately 25%). Sixty-five percent of patients showed clinical improvement, with a maximum rate of satisfactory response observed in major depression. Severe side effects, such as symptomatic hypotension or confusion, were seen in 20% of patients. Because of 10- and 15-fold interindividual variations in the concentrations of clomipramine and its metabolite, respectively, therapeutic drug monitoring can provide valuable assistance to clinical judgment in individual dose adjustment for patients whose old age, associated somatic diseases, and comedication necessitate additional precautions.  相似文献   
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Studies of spatial representation generally focus on flat environments and visual input. However, the world is not flat, and slopes are part of most natural environments. In a series of 4 experiments, we examined whether humans can use a slope as a source of allocentric, directional information for reorientation. A target was hidden in a corner of a square, featureless enclosure tilted at a 5° angle. Finding it required using the vestibular, kinesthetic, and visual cues associated with the slope gradient. In Experiment 1, the overall sample performed above chance, showing that slope is sufficient for reorientation in a real environment. However, a sex difference emerged; men outperformed women by 1.4 SDs because they were more likely to use a slope-based strategy. In Experiment 2, attention was drawn to the slope, and participants were prompted to rely on it to solve the task; however, men still outperformed women, indicating a greater ability to use slope. In Experiment 3, we excluded the possibility that women's disadvantage was due to wearing heeled footwear. In Experiment 4, women required more time than men to identify the uphill direction of the slope gradient; this suggests that, in a bottom-up fashion, a perceptual or attentional difficulty underlies women's disadvantage in the ability to use slope and their decreased reliance on this cue. Overall, a bi-coordinate representation was used to find the goal: The target was encoded primarily with respect to the vertical axis and secondarily with respect to the orthogonal axis of the slope. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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Measurements of dynamic viscoelastic in-plane shear modulus have been made for unidirectional carbon fiber composites with amorphous engineering thermoplastics as the binder resins. The viscoelastic response is modeled by a three-phase, finite-element model in which fiber placement in the plane perpendicular to the fiber axes is largely disordered. In the model, fibers tend to chain with the distance of closest approach dictated by several factors, including the tendency for the resin to wet the entire fiber surface. Polished section microscopy supports the assumed microstructure. The model includes an adsorbed primer layer at the fiber interface with perturbed viscoelastic response. The model is useful throughout the temperature range up to and including the glass transition of the binder resin.  相似文献   
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Memories for spatial locations often show systematic errors toward the central value of the surrounding region. This bias has been explained using a Bayesian model in which fine-grained and categorical information are combined (Huttenlocher, Hedges, & Duncan, 1991). However, experiments testing this model have largely used locations contained in simple geometric shapes. Use of this paradigm raises 2 issues. First, do results generalize to the complex natural world? Second, what types of information might be used to segment complex spaces into constituent categories? Experiment 1 addressed the 1st question by showing a bias toward prototypical values in memory for spatial locations in complex natural scenes. Experiment 2 addressed the 2nd question by manipulating the availability of basic visual cues (using color negatives) or of semantic information about the scene (using inverted images). Error patterns suggest that both perceptual and conceptual information are involved in segmentation. The possible neurological foundations of location memory of this kind are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Photographic forensic evidence for the global collapse of the World Trade Center (WTC) towers was developed as part of the National Institute of Standards and Technology (NIST) WTC collapse investigation. The libraries accumulated during the Federal Emergency Management Agency/American Society of Civil Engineers study and NIST investigations were searched for images that showed gross building distortions preceding or during the collapse events. Frames or images showing draw-in of the cast face of WTC 2 and the south face of WTC 1 were analyzed to map the distortion field, which was tracked over time. The inward distortions increased in magnitude as the building burned, reaching a maximum at the time of collapse. Evidence of dropped floors within the towers before global collapse was developed, as was evidence of the kinking and rotation of the top portion of WTC 2 just before and during collapse.  相似文献   
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