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21.
JG Mulder 《Canadian Metallurgical Quarterly》1995,14(12):1052-1056
Eight hundred and ninety-two strains of Staphylococcus species were identified by means of desferrioxamine susceptibility and fermentation results of three carbohydrates, with the API Staph system (bioMérieux, France) as reference method. No identification could be obtained for 34 strains with API Staph. Of the remaining 858 strains, identical identification was obtained with 842 (98.1%). All 707 strains identified as Staphylococcus epidermidis or Staphylococcus hominis by the API Staph system were found to be desferrioxamine susceptible, and all but 5 (3.3%) of 151 strains identified as other staphylococcal species were found to be resistant, yielding an identification correlation of 99.4% for desferrioxamine. The five additional strains which were susceptible to desferrioxamine were identified as Staphylococcus capitis (2 strains), Staphylococcus lugdunensis (2 strains), and Staphylococcus warneri (1 strain) by API Staph, and as Staphylococcus epidermidis (1 strain), Staphylococcus hominis (3 strains), and one other staphylococcal species by the experimental system. 相似文献
22.
In this paper, a biorthogonal-like sequences (BLS) theory and its application to the generalized Gabor expansions (equivalently, the generalized short-time Fourier transform/filterbank summation) are presented. A pair of BLS's are defined to be two sequences satisfying a biorthogonal-like condition (BLC), which is a moment equation and equivalent to a linear difference equation. We show that two collections in a Hilbert space generated by a pair of BLS's in the joint time-frequency domain are complete, either can be used as an analysis filter, and the other can be used as a synthesis filter for a generalized Gabor expansion of discrete-time signals. A sufficient and necessary condition on the existence of BLS's based on the moment equation is presented, which is simpler to use than frame theory. Given a filter generating a frame, its BLS's also generate frames. The dual frame is one of them. Given a FIR analysis/synthesis filter, there is a FIR synthesis/analysis filter if BLS's exist. The algorithm to compute FIR analysis and synthesis filters based on the linear difference equation is presented in this paper, which is simpler than frame operator 相似文献
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Morris Driels John Klegka 《The International Journal of Advanced Manufacturing Technology》1992,7(1):29-37
This article presents a comparative analysis of contemporary printed wiring assembly (PWA) batch manufacturing systems employing
surface mount technology (SMT), This analysis is accomplished by reviewing a typical case study of PWA manufacturing system
in the USA. A previously developed model is then applied to the system to predict the cost and performance in the production
of typical PWA designs. Various modifications to the system are then proposed and evaluated. From the case study, conclusions
concerning optimum manufacturing system configuration for this industry can be drawn and are presented. 相似文献
25.
The kinematic error compensation of robot manipulators is at present being attempted by improving the precision of the nominal robot kinematic parameters. This paper addresses the problem of kinematic compensation using a new mathematical joint model proposed to account for shortcomings in existing methods. The corrected manipulator transformation is formulated in terms of “generalized Jacobians”: relating differential errors at the joints to the differential change in the manipulator transformation. The details of application are discussed for a particular industrial manipulator. 相似文献
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27.
Zautra Alex J.; Okun Morris A.; Robinson Sharon E.; Lee Douglas; Roth Sanford H.; Emmanual Jansen 《Canadian Metallurgical Quarterly》1989,8(1):1
Studied the relation between life stress and immune parameters for 33 30–70 yr old female rheumatoid arthritis (RA) patients interviewed during 3 routine monthly clinic checkups. Life stress from major and minor events, coping efficacy, and self-reported psychological distress were assessed, and immunofluorescence of T-cells and B-cells was performed on the blood drawn during each visit. Small stressful events were positively related to the proportion of circulating B-cells, psychological distress was inversely related to proportion of circulating T-cells, and major life events were associated with lower T-helper/T-suppressor cell ratios. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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SA Syed KS Zahir JR Zink O Saglaam RJ Restifo JG Thomson 《Canadian Metallurgical Quarterly》1997,38(4):396-403
Reinstatement and spontaneous recovery of previously extinguished nicotine-taking behavior were examined in rats. Male subjects were trained to self-administer nicotine (30 microg/kg per infusion, IV; one 60-min session per day for 3 weeks). Extinction sessions were then given for 5-10 days during which saline was substituted for nicotine. Subsequently, in the first set of tests for nicotine seeking, the reinstatement of lever presses that previously delivered nicotine was examined after priming injections of saline and nicotine (75, 150 and 300 microg/kg, SC; and 30 and 60 microg/kg, IV). In the second set of tests for nicotine-seeking, rats were tested after an additional 21-day drug-free period during which they were not exposed to the self-administration chambers (a test for the spontaneous recovery of drug seeking), and after priming injections of nicotine (150 and 300 microg/kg, SC). Reinstatement of extinguished food-reinforced behavior after exposure to nicotine was also determined. Priming injections of nicotine reinstated nicotine seeking regardless of the route of administration. In addition, previously extinguished nicotine seeking recovered spontaneously after a 21-day period during which rats were not exposed to the drug-taking environment. Nicotine also reinstated extinguished food-reinforced behavior in rats with a history of nicotine self-administration, but not in drug-naive rats. The present results extend previous work with opioid and stimulant drugs on reinstatement of drug seeking by the self-administered drug. It also appears that, as with other positive reinforcers, the mere passage of time is a sufficient condition for the spontaneous recovery of extinguished nicotine seeking. 相似文献
30.