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STRONG METAL-CERAMIC JOINTS 总被引:3,自引:0,他引:3
In this paper the technology for joining metals to ceramics is reviewed. The technologies of metal powder sintering, liquid phase joining with activated brazing alloys and with ceramic frit, solid-state joining, friction welding and mechanical fixation are described. In order to put some perspective on the mechanical data given in the literature, some evaluating remarks on mechanical testing are made. 相似文献
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Early patterning of prelimbic cortical axons to the striatal patch compartment in the neonatal mouse
LK Nisenbaum SM Webster SL Chang KD McQueeney JJ LoTurco 《Canadian Metallurgical Quarterly》1998,20(2-3):113-124
The striatum receives excitatory input from virtually the entire cerebral cortex. In the adult, this input is segregated into two functionally distinct compartments of the striatum, the patch (striosome) and matrix regions. This study determined whether the patterning of corticostriatal afferents from the prelimbic cortex to the striatal patch compartment develops during the early period of collateral formation or instead at the time of peak synaptogenesis. Initial formation of corticostriatal axon collaterals was observed by embryonic day (E) 19. Quantification of corticostriatal collaterals revealed a significant increase in the number and complexity of collateral branches at postnatal day 6 as compared to E19. Concomitant with the increase in collateral branching, a heterogeneous pattern of collateralization consisting of parallel rows of corticostriatal collaterals was observed in the medial striatum. In addition to the rows, clusters of corticostriatal axons occurred more laterally. These clusters colocalized with patches of dense tyrosine hydroxylase-positive fibers, a marker for the striatal patch compartment in the neonatal mouse. Together, these data indicate that corticostriatal patterning occurs during the period of early axon collateralization resulting in a segregation of corticostriatal axon collaterals from the prelimbic cortex to the striatal patch compartment. 相似文献
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OBJECTIVES: To assess that neuromuscular relaxation onset of the adductor pollicis (AP) is related to neuromuscular stimulation rate. To assess that train-of-four (TOF) at 0.05 Hz is a more accurate indicator of optimal tracheal intubation time and conditions, than TOF at 0.08 Hz. STUDY DESIGN: Prospective, comparative, randomized double-blind study. PATIENTS: Forty adults, physical class ASA 1 or 2, undergoing general anaesthesia with tracheal intubation were allocated to two groups (n = 20) according to the sequence of stimulation of the AP: either TOF at 0.05 Hz (test group) or TOF at 0.08 Hz (control group). METHODS: Induction of anaesthesia was achieved with thiopentone, fentanyl and vecuronium (0.1 mg.kg-1). Neuromuscular monitoring was obtained with force displacement transducers attached to each AP. Tracheal intubation was performed once AP muscular response obtained with TOF at 0.05 Hz for test group and TOF at 0.08 Hz for control group was abolished. Results are expressed as mean +/- SEM. Fisher exact test was used for intubation conditions comparison. Curarization time between groups was compared with unpaired Student's t test (P < 0.05 accepted). RESULTS: TOF with 0.05 Hz stimulation significantly increased curarization time: 217 +/- 7 versus 162 +/- 6 s (P < 0.001). Intubation conditions were excellent in 95% and good in 5% of patients in the study group, compared to 15 and 40% in the control group, respectively (P < 0.01) in 45% of the control group patients coughing at intubation occurred. CONCLUSION: Low stimulation rate (TOF at 0.05 Hz) of AP is a reliable technique to determine the appropriate intubation time for patients paralyzed with vecuronium. 相似文献
15.
AG Niessen JG Bollemeijer RJ de Keizer PH de Meijer 《Canadian Metallurgical Quarterly》1994,138(15):770-775
OBJECTIVE: To assess how often the aetiology is established in patients with uveitis, what systemic disease are found and what is the contribution of the internist to the diagnostic process. DESIGN: Retrospective study. SETTING: University Hospital Leiden, the Netherlands. METHOD: From January 1987 to April 1992, 342 patients presented with uveitis. All patients underwent a standard ophthalmological examination. Referral to an internist and individualised laboratory screening followed in patients with recurrent, chronic, bilateral or panuveitis. Recorded were: ophthalmological data, results of laboratory screening, results of analysis by the internist, final diagnosis and presence of systemic disease. RESULTS: 149 (44%) patients were examined by the internist, 18 (5.2%) were seen by another specialist. In 169 (49%) patients a specific diagnosis was made. 74 (22%) had a systemic disease, 74 a primary ocular disease. In 28 (8%) a systemic disease was presumed (5% were HLA-B27 positive, 3% had abnormal laboratory results); 5 (1%) patients had endophthalmitis as a complication of a septic process. CONCLUSION: In approximately 1/3 of the patients with uveitis a systemic disease was found. Examination by the internist tailored to the individual patient is essential in the evaluation of uveitis patients. 相似文献
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A. P. J. Voncken A. F. J. Hammen A. T. A. M. de Waele 《Journal of Low Temperature Physics》1996,102(3-4):335-348
In this paper we describe the effect of the vicinity of a liquid3He-vacuum interface on the behavior of a vibrating wire viscometer. It was found that in the fluid near the liquid interface the quality factor is lower than in the bulk liquid. We further report on the observation of a doubling of the resonance peak of the wire in a saturated3He-4He mixture. The frequencies and amplitudes of the two peaks strongly depend on the distance between the phase boundary and the vibrating wire; the temperature and the velocity of the phase boundary have no significant influence on the peak frequencies. The observed peak doubling is attributed to the coupling of the vibrating wire with a standing second-sound wave in the dilute phase where the volume of the dilute phase can be regarded as a resonating cavity for second sound. 相似文献
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From visual data exploration to visual data mining: a survey 总被引:8,自引:0,他引:8
Ferreira de Oliveira M.C. Levkowitz H. 《IEEE transactions on visualization and computer graphics》2003,9(3):378-394
We survey work on the different uses of graphical mapping and interaction techniques for visual data mining of large data sets represented as table data. Basic terminology related to data mining, data sets, and visualization is introduced. Previous work on information visualization is reviewed in light of different categorizations of techniques and systems. The role of interaction techniques is discussed, in addition to work addressing the question of selecting and evaluating visualization techniques. We review some representative work on the use of information visualization techniques in the context of mining data. This includes both visual data exploration and visually expressing the outcome of specific mining algorithms. We also review recent innovative approaches that attempt to integrate visualization into the DM/KDD process, using it to enhance user interaction and comprehension. 相似文献