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101.
JJ Breton L Bergeron JP Valla C Berthiaume M St-Georges 《Canadian Metallurgical Quarterly》1998,37(11):1167-1174
OBJECTIVE: To examine the reliability of the French Diagnostic Interview Schedule for Children (DISC-2.25) in Quebec in light of other DISC-2 studies conducted in the National Institute of Mental Health's Methods for the Epidemiology of Child and Adolescent Mental Disorders Study. METHOD: Reliability was assessed for DSM-III-R disorders in a community sample comprising 260 parents of youths aged 6 to 14 years and 145 adolescents aged 12 to 14 years. The DISC was completed at home. The mean test-retest interval was 13.8 days for parents and 12.8 days for adolescents. RESULTS: Parents' reports: Internal consistency was acceptable for a majority of disorders. The kappa coefficients were in the fair or good ranges except for depressive disorders and were higher for children than for adolescents, and intraclass correlations were higher than kappa coefficients. Adolescents' reports: Internal consistency was acceptable or nearly acceptable for a majority of disorders. The kappa coefficients were in the fair range, and intraclass correlations were higher than kappa coefficients. The kappa coefficients were significantly higher for the test-retest interval of 7 to 14 days than for 14 to 21 days for adolescents' reports of anxious disorders and internalizing disorders. CONCLUSION: The French DISC-2.25 shows acceptable internal consistency and fair to good test-retest reliability. Across DISC-2 studies, test-retest reliability of the parents' reports improved for anxiety and depressive disorders. Among sources of variation, studies on attributes of questions would be meaningful. 相似文献
102.
Development of nano-composite lead-free electronic solders 总被引:1,自引:0,他引:1
Inert, hybrid inorganic/organic, nano-structured chemicals can be incorporated into low melting metallic materials, such as
lead-free electronic solders, to achieve desired levels of service performance. The nano-structured materials technology of
polyhedral oligomeric silsesquioxanes (POSS), with appropriate organic groups, can produce suitable means to promote bonding
between nano-reinforcements and the metallic matrix. The microstructures of lead-free solder reinforced with surface-active
POSS tri-silanols were evaluated using scanning electron microscopy (SEM). Wettability of POSS-containing lead-free solders
to copper substrate was also examined. Steady-state deformation of solder joints made of eutectic Sn-Ag solder containing
varying weight fractions of POSS of different chemical moieties were evaluated at different temperatures (25°C, 100°C, and
150°C) using a rheometric solids analyzer (RSA-III). Mechanical properties such as shear stress versus simple shear-strain
relationships, peak shear stress as a function of rate of simple shear strain, and testing temperature for such nano-composite
solders are reported. The service reliability of joints made with these newly formulated nano-composite solders was evaluated
using a realistic thermomechanical fatigue (TMF) test profile. Evolution of microstructures and residual mechanical property
after different extents of TMF cycles were evaluated and compared with joints made of standard, unreinforced eutectic Sn-Ag
solder. 相似文献
103.
104.
Ghinwa Naja Bohumil Volesky Andre Schnell 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(4):648-658
A specially designed bioreactor including an axial microfilter for cell retention was evaluated for continuous‐flow operation with selected liquid media as controls and in aerobic cultivations of Saccharomyces yeasts. In the initial tests, performance characteristics such as filtration rates and cell accumulation were assessed as a function of filter rotational speed, operating pressure, cultivation time and microfilter type (i.e. membrane or porous metal). The bioreactor did not perform satisfactorily when viscous extracellular polymer was present in the liquid. In the continuous‐flow culture enabling cell retention, Saccharomyces cerevisiae yeast cell concentrations were enhanced by as much as 16‐fold over ordinary batch growth. Concomitant filtration rates were stable over operating times of up to 130 h and hence were independent of the cell concentration. The maximum steady‐state flux was enhanced at rotational speeds up to 400‐700 rpm ranging from 22 to 42 L m?2 h?1. Higher rotation rates offered no further improvements. The maximum stabilized flux was independent of operating pressure. Pressure increases caused momentary flux improvements, which rapidly declined and eventually restabilized. Copyright © 2006 Society of Chemical Industry 相似文献
105.
O Vanhooteghem W Courtens J Andre U Sass M Song 《Canadian Metallurgical Quarterly》1998,15(5):374-377
Hermansky-Pudlak syndrome is a rare, inherited, autosomal recessive disease. Diagnosis is based on a triad of signs: oculocutaneous albinism, a hemorrhagic tendency due to a platelet disorder, and an accumulation of lipopigments in different organs, particularly the medullary macrophages. We describe a child with the characteristic findings of this syndrome, which often goes unrecognized because of the discrete nature of the cutaneous and hemorrhagic manifestations. This diagnosis is important because of the risk not only of hemorrhage but also of granulomatous colitis and long-term pulmonary fibrosis. 相似文献
106.
Administered a modified version of a Piagetian test on the concept of relative velocity (including questions on the duration of relative displacements) to 96 children placed in age groups of 7, 9, 11, and 13 yr. It was found that (a) the developmental stages of the concept were comparable to those observed by Piaget except for formal operations which seem to evolve later; (b) the combination of 2 movements of same direction but unequal velocity is more difficult to synthesize than any other; (c) success on the problem of durations is not a prerequisite of at least partial success on the problem of velocities; and (d) complete success on the problem of velocities is not necessarily verbalized in spatio-temporal terms. To explain the difficulty observed in synthesizing velocities, the importance of the instructions (e.g., specifying the speed of each mobile) and of changes in the spatial order of the mobiles was emphasized. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
This paper intends firstly to present how digital switching was introduced into the French network nearly ten years ago and what are the main advantages brought by digital switching systems. Various cases in the network such as trunk or local exchanges are examined; general as well as particular advantages are shown. Secondly, the technical requirements for these exchanges are described; an emphasis is put on the specific aspects of digital switching. Digital switching systems already in operation or on the verge of being commissioned are outlined. Finally, different tables give information concerning mainly the number of subscriber lines connected to class 3 and 4 digital exchanges by the end of 1978. 相似文献
108.
109.
Andre Abad 《Microscopy research and technique》1988,8(2):217-222
To prevent section wrinkles usually encountered with the use of coated single-hole grids, a simple method was developed. Formvar film resting on a platform with holes (3.5 mm diameter) was heated with a slide warmer (60–65°C). The bottom of a glass petri dish was inverted over the platform to keep the ambient air at the desired temperature. Sections were picked up from the boat of the diamond knife with a single-hole grid and deposited at the orifice of the platform and allowed to dry. The grids were then carefully pushed through the orifice of the platform with the blunt head of a nail (3 mm diameter). 相似文献
110.
Recent in vivo studies suggest that tumor necrosis factor-alpha (TNF-alpha) is involved in the development of the thymus. We postulated that this inflammatory mediator could regulate the influx of progenitor T cells into the thymus. Using an in vitro static adhesion system, we found that TNF-alpha increases the adhesion of a murine progenitor T cell line (FTF1) to a bovine aortic endothelial cell line (1F8), human umbilical vein endothelial (HUVE) cells, and a murine arterial endothelial (MAE) cell line. TNF-alpha treatment of the 1F8 cells resulted in a time- and dose-dependent increase in the adherence of FTF1 cells. Adherence increased during the first 6 hr of treatment with TNF-alpha concentrations ranging from 10(-11) to 10(-9) M. Maximal adherence (6 hr treatment with 10(-10) M of TNF-alpha) was approximately 4.5-fold larger than that of untreated monolayers. A slow decrease in adherence, down to approximately 2-fold at 48 hr, was observed beyond 12 hr of TNF-alpha treatment; in contrast, removal of TNF-alpha after 6 hr of continued stimulation caused the adherence to return to pre-stimulation levels within 24-30 hr. Adhesion of FTF1 cells to TNF-alpha treated 1F8 cells was almost completely blocked by a monoclonal antibody against murine CD49d (very late antigen-4) expressed on FTF1 cells. TNF-alpha-induced adhesion of FTF1 cells to MAE cells was also blocked by monoclonal antibodies against murine CD49d and CD106 (vascular cell adhesion molecule-1). These results support the notion that local secretion of TNF-alpha could modulate the dynamics of adhesion of progenitor T cells to the thymic endothelium. 相似文献