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This article introduces and provides the context for the themed section on mobile communication in Asia. It suggests that much work remains to be done in adequately grasping the new mobile, mediated face of communication in the very diverse Asian region. It also suggests that such a new direction in research needs to go hand in hand with rethinking the conceptual and theoretical bases of mobile, and indeed, Internet and computer‐mediated communication.  相似文献   
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BACKGROUND: Ossification of the posterior longitudinal ligament (OPLL) may cause neuropathic bladder dysfunction due to spinal cord involvement. OPLL, unlike a traumatic spinal cord lesion, progresses insidiously and sometimes affects longer cord segments. As the manifestation of bladder dysfunction may depend on the development of OPLL, we studied the relationship between bladder function and roentgenographic changes in the spinal canals of OPLL patients. PATIENTS AND METHODS: Eighteen surgical candidates (11 males and 7 females, 34 to 85 years old) were studied urodynamically. Sixteen underwent CO2-filling cystometry, uroflowmetry and measurement of their residual urine volume. Cystometry was omitted in the remaining 2 patients. The vertical extent of OPLL and the degree of stenosis in the spinal canal was estimated by x-ray films and CT. RESULTS: The cystometric study revealed detrusor hyperreflexia in 2 patients and areflexic or underactive detrusors in 5 patients. Intermittent flows or considerable amounts of residual urine were also observed in the arefilexia/underactive group. Uroflowmetry showed a normal flow with little residual urine in both patients in whom cystometry was omitted. Bladder sensation was maintained in all patients. The occurrence of abnormal detrusor activity had no relationship to the degree of canal stenosis, while the occurrence of an areflexic or underactive detrusor correlated with the vertical extent of OPLL. CONCLUSION: Although detrusor hyperreflexia is common in an upper spinal cord lesion, attention should also be paid to the development of detrusor underactivity in patients with a wide vertical extent of OPLL.  相似文献   
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Reports for 1982 are listed for the following regional association meetings: Sixty-Second Annual Meeting of the Western Psychological Association; Fifty-Second Annual Meeting of the Rocky Mountain Psychological Association; Fifty-Fourth Annual Meeting of the Midwestern Psychological Association; Twenty-Eighth Annual Meeting of the Southeastern Psychological Association; Twenty-Eighth Annual Meeting of the Southwestern Psychological Association; Twenty-Second Annual Meeting of the New England Psychological Association; Fifty-Third Annual Meeting of the Eastern Psychological Association; and Seventy-Fourth Annual Meeting of the Southern Society for Philosophy and Psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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OBJECTIVE: To assess the effect of percutaneous endoscopic gastrostomy (PEG) tube placement on gastric emptying in clinically normal cats. ANIMALS: 8 healthy adult 3- to 5-year-old cats. PROCEDURE: Cats were accommodated to the diet for 2 weeks prior to scintigraphy. Caloric needs were divided into 3 feedings/d. Food was withheld for 24 hours after tube placement, then was fed as a third of the caloric needs on day 1, two-thirds on day 2, and full caloric requirements thereafter. Gastric emptying was measured via nuclear scintigraphy. Labeled meals contained 111 MBq (3 mCi) of 99mTc-labeled disofenin. Sixty-second ventral scintigraphic images were acquired immediately, every 20 minutes for the first hour, then every 30 minutes for 4 hours after feeding. Each cat was evaluated 3 times prior to PEG tube placement. Cats were anesthetized, and 16-F mushroom-tipped Pezzar gastrostomy tubes were placed, using a video endoscope. Scintigraphy was repeated on days 1, 4, 7, 11, 14, and 21 after PEG tube placement. RESULTS: Gastric emptying was faster with a PEG tube in place. Percentage of retained gastric activity was significantly lower after PEG for 150, 180, 210, and 240 minutes versus time before PEG tube placement. CONCLUSION: Placement of a PEG tube does not delay gastric emptying in clinically normal cats. CLINICAL RELEVANCE: Gastric retention of food, vomiting, and aspiration pneumonia after PEG tube placement may not be related to delayed gastric emptying.  相似文献   
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For each N, and each fixed time T, a signal XN and a `noisy' observation YN are defined by a pair of stochastic difference equations. Under certain conditions (XN, YN) converges in distribution to (X, Y, where dX(t)= f(t, X(t))dt+dV( t), dY(t)=g(t, X( t))dt+dW(t). Conditions are found under which convergence in distribution of the conditional expectations E{F(XN)|YN} to E{F(X)|Y} follows, for every bounded continuous function F. The case in which the conditional expectations still converge but the limit is not E{ F(X)|Y} is also studied. In the situation where f and g are linear functions of X, an examination of this limit leads to a Kalman-Bucy-type estimate of X N which is asymptotically optimal and is an improvement on the usual Kalman-Bucy estimate  相似文献   
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A detailed commercial process for the synthesis and purification of the activated disaccharide, α-D -cellobiosyl bromide heptaacetate ( 1 ) was developed. Reaction of α-D -cellobiose octaacetate (CBO) with HBr in glacial acetic acid or in glacial acetic acid/methylene chloride combination affords α-D -cellobiosyl bromide heptaacetate in high yield and excellent quality. Process variables such as reaction solvent, reaction time, reaction temperature, HBr stoichiometry, isolation methods and product purification options were optimized for large-scale synthesis. α-D -Cellobiosyl bromide heptaacetate was successfully prepared in a commercial manufacturing plant.  相似文献   
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A precue paradigm was used to examine the time it takes to restructure a planned motor response. Two groups of subjects, a young group and an elderly group, performed an aiming task in which 75% of the trials involved no change of movement parameters. On remaining trials, subjects had to change one or more of the movement parameters. Elderly subjects had slower reaction times (RTs), movement times, and made more errors in both conditions. Elderly subjects had proportionally longer RTs overall, independent of restructuring a movement plan. Preparation of arm and direction also exhibited a proportional increase in RT. However, differential aging effects were found for preparation of extent. Elderly subjects were slower preparing short movements compared with long movements, whereas young subjects showed the opposite trend. These results suggest that with advancing age, operations concerned with movement-plan restructuring for arm and direction undergo change in processing rate, whereas operations for extent undergo more extensive alteration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Metallized, flexible polymeric reflector materials are much lighter and potentially less expensive than the conventional glass/metal mirrors often used in solar thermal concentrators such as heliostats and parabolic dishes and troughs. Unweathered silvered-PMMA reflectors have a solar reflectance at least as high as glass reflectors, but their environmental durability needs to be demonstrated. ECP-305, a silvered-PMMA film available commercially from the 3M Company and developed in collaboration with the National Renewable Energy Laboratory, is the current state of the art. Important progress has been made in overcoming the three primary mechanisms causing ECP-305 to lose reflectance. These mechanisms are: (1) photon-induced silver corrosion, (2) surface soiling, and (3) a form of delamination called tunneling. Given the progress in resolving these performance lifetime issues, silvered-PMMA films should meet the reflectance and durability goals.  相似文献   
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