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51.
Electrically controllable all-fiber PMD emulator using a compact array of thin-film microheaters 总被引:2,自引:0,他引:2
Hauer M.C. Yu Q. Lyons E.R. Lin C.H. Au A.A. Lee H.P. Willner A.E. 《Lightwave Technology, Journal of》2004,22(4):1059-1065
An electrically controllable, all-fiber polarization-mode dispersion (PMD) emulator is constructed using thin-film microheaters to temperature tune the birefringence of 30 PM-fiber sections spliced at 45/spl deg/ angles. Compact packaging is achieved by mounting the fiber heaters onto an array of silicon V-grooves. The advantages of this electrically tunable emulator design are low loss, negligible PDL, simple construction, no internal reflections, and no moving parts. 相似文献
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Efficacy of praziquantel (0.25 mg kg(-1)) on the cecal tapeworm (Anoplocephala perfoliata) in horses
Aspiration of inflorescence or grass heads (seed head of grasses) often presents with atypical signs and symptoms because grass heads have a tendency to rapidly migrate to the periphery of the lung. If this is not recognized, it can lead to delay in diagnosis and serious complications. Removal with rigid bronchoscopy maybe difficult, and surgery is often needed. We report a case of a seven-month-old child who had a delayed diagnosis of grass head aspiration and subsequently presented with a life threatening tension pneumothorax. This case highlights the importance of obtaining a detailed history in cases of foreign body aspiration and the need to include it in the differential diagnosis of unexplained respiratory symptoms, especially those of sudden onset in children. 相似文献
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CF Wu B Haider SS Ahmed HA Oldewurtel MM Lyons TJ Regan 《Canadian Metallurgical Quarterly》1977,55(1):200-205
The effects of chronic tolbutamide treatment were examined in a diabetic animal model in which abnormal myocardial function and composition have previously been demonstrated. Eight diabetic dogs were given tolbutamide 250 mg/day orally and compared with seven untreated diabetics, five healthy dogs receiving tolbutamide, and eight normal controls. After one year, resting hemodynamic studies in the intact anesthetized state showed that treated diabetic dogs had a significantly higher left ventricular end-diastolic pressure of 12.1+/-1.3 mm Hg associated with normal end-diastolic volume, compared to 6.1+/-0.8 mm Hg in untreated diabetics (P less than 0.01) and 6.3+/-0.5 in normals. Stroke work and ejection fraction were similar to normals. Acute volume expansion revealed a larger rise of left ventricular end-diastolic pressure in treated and untreated diabetics than normals, without a significant stroke volume response in treated diabetics. Enhanced stiffness of myocardium appeared to be related to interstitial accumulation of periodic acid-Schiff staining material, further intensified in treated diabetics by triglyceride accumulation observed on electron microscopy and by chemical analysis. Thus treatment of diabetes with tolbutamide, despite improved glucose tolerance, effected further reduction of left ventricular function and altered morphology of myocardium. 相似文献
56.
Kay Edwin J.; Lyons Arthur; Newman William; Mankin Donald; Loeb Roger C. 《Canadian Metallurgical Quarterly》1978,46(3):470
251 undergraduates completed the California Psychological Inventory,, the Adjective Check List, and a drug-use questionnaire in the fall of their freshman year and in each of 1, 2, or 3 succeeding springs. Three prevailing patterns of drug use were identified: (a) Continuous nonusers never disclosed marijuana use; (b) switched nonusers did not disclose marijuana use initially but did so on a later questionnaire, and (c) users disclosed marijuana use both initially and later. Enduring differences between users and continuous nonusers were found. The switched nonusers generally had scores between those of the users and continuous nonusers. On several scales, switched nonusers were similar to users both before and after their use of marijuana. It is concluded that marijuana use, both present and future, can be predicted by a certain pattern of reported personality characteristics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
An application of the recently developed thin-walled box beam element to the analysis of multibox bridges which arises in practical design, is presented. The thin-walled box beam element, which also takes account of warping distortional effects, when combined with traditional beam elements into a grillage model may adequately represent the three-dimensional behaviour of multibox superstructure. Equivalent sectional properties for the transverse grillage members across individual boxes are computed from a frame analysis. A numerical iterative procedure is introduced to take account of the interaction due to distortion.Comparisons with other numerical methods and model experiments demonstrate the accuracy and economy of the proposed method. 相似文献
58.
Using survey data from 2,000 low-income adult respondents in each of five states, this DataWatch assesses how uninsured, low-income adults differ from low-income adults who have public or private insurance and how Medicaid expansions have affected insurance coverage patterns across states with different eligibility policies. Findings show that the proportion of low-income uninsured adults is two to three times higher in states that have not expanded Medicaid eligibility beyond relatively low welfare levels. Compared with persons who have either Medicaid or private insurance, uninsured persons report more difficulties getting needed care, are less likely to have a regular provider, and rate the care they do receive as lower quality. 相似文献
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SA Eisen R Neuman J Goldberg WR True J Rice JF Scherrer MJ Lyons 《Canadian Metallurgical Quarterly》1998,60(5):533-539
STATEMENT OF PROBLEM: Use of temporary crowns and fixed partial dentures is especially relevant when the treatment plan requires restorations for long interim periods, and the in-service discoloration of provisional restorative materials is a major drawback. PURPOSE: This study evaluated the discoloration effect of coffee and tea on some materials that are commonly used in the fabrication of provisional restorations. MATERIAL AND METHODS: Six commercially available provisional resins (Jet, Caulk TBR, Protemp Garant, Luxatemp Solar, Provipont DC and SR-Ivocron-PE) were evaluated after 1 day, 7 days, and 30 days of immersion in various staining solutions. Color measurements were obtained by using a Dr Lange Micro Color tristimulus colorimeter and color differences (delta E*) were estimated. RESULTS: The 2 chemically activated resins (Jet and Caulk TBR) and the heat-cured resin (SR-Ivocron PE) exhibited the least color changes, whereas the Provipont-DC resin was the least color stable. After immersion for 30 days, the combination with the coffee solution resulted in unacceptable discoloration for all the tested materials. CONCLUSIONS: Provisional restorative materials, staining solutions, and immersion time were significant factors that affected color stability. After immersion for 7 days, all materials showed observable color changes. The composite-based materials, especially light-curing composites, were the least color stable. The coffee solution exhibited more staining capacity than the tea solution. 相似文献