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121.
LA Mastaj DJ Tartakow AJ Borislow MS Fogel 《Canadian Metallurgical Quarterly》1994,15(1):74, 76, 78-80, passim; quiz 86
Infections present a significant hazard in the orthodontic office because they can be transmitted by blood or saliva through direct or indirect contact, droplets, aerosols, or contaminated instruments and equipment. Because the incidence of certain microbial cross-infections in the dental environment has not been well documented, orthodontic personnel may not take the problem of cross-infection as seriously as they should, and they may transmit or contract more infections than they realize. The use of effective infection-control procedures in the orthodontic office and laboratory will prevent cross-contamination that may extend to the orthodontist, office staff, assistants, and patients. The goal of this article is to present infection control in a simple, yet comprehensive, manner, and to encourage all orthodontic practitioners to implement essential infection-control procedures in their practices. 相似文献
122.
Gender differences were examined in the context of situational effects. Participants monitored interpersonal behavior for 20 days, using an event-sampling strategy. The monitored behaviors reflected dominance and submissiveness (components of agency) and agreeableness and quarrelsomeness (components of communion). The situations reflected differences in the status of work roles: interactions with boss, co-worker, and supervisee. Status influenced agency. Individuals were most agentic when with a supervisee and least agentic when with a boss. Gender did not influence agency but did influence communal behaviors. Women were more communal regardless of social role status; women were especially communal with other women, compared with men with men. Findings about agency supported a social role theory interpretation of gender differences. Results for communion were consistent with accounts of the influence of sex segregation on interpersonal relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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In the present study, the effect of bradykinin on basal and precontracted mouse-isolated trachea was investigated. In basal conditions mouse-isolated tracheal rings do not respond to bradykinin. However, when the tracheal rings were precontracted with carbachol (10(-7) M) a relaxation with bradykinin (3 x 10(-9)-3 x 10(-7)) was found. The maximal response amounted 69.7+/-4.1% (n=15) with a pD2 value of 7.2+/-0.21. The selective bradykinin B2 receptor antagonist HOE 140 (10(-10)-10(-8) M) antagonized the bradykinin-induced relaxation, while the bradykinin B1 receptor antagonist des-Arg9-Leu8-bradykinin (10(-6) M) had no influence. The selective bradykinin B1 receptor agonist des-Arg9-bradykinin (10(-6) M) caused a small relaxation (8.4+/-2.5%, n=6), which could be antagonized completely by the selective bradykinin B1 receptor antagonist des-Arg9-Leu8-bradykinin (10(-6) M) while addition of the selective bradykinin B2 receptor antagonist HOE 140 (10(-8) M) was without effect. In the presence of indomethacin (10(-6) M) the relaxation of bradykinin was completely abolished. Pretreatment of the tracheal rings with capsaicin, or the presence of the selective NK1 receptor antagonist RP 67851 (10(-6) M) or the presence of the nitric oxide synthase inhibitor L-NAME (3 x 10(-4) M) had no effect on the bradykinin-induced relaxation. In conclusion, these results demonstrate that the mouse-isolated tracheal is a preparation in which bradykinin exerts a relaxant response via stimulation of bradykinin B2 receptors. This response is probably mediated by prostaglandins. 相似文献
125.
Sandra Aparecida de Assis Pedro Fernandes Bruno Sommer Ferreira Joaquim MS Cabral Olga Maria Mascarenhas Faria Oliveira 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(3):277-280
A partially purified extract of pectinmethylesterase (PME) from acerola fruit was immobilized on various supports: glass, celite, chrysotile, agarose, concanavalin A Sepharose 4B, egg shell, polyacrylamide and gelatin. In addition, reticulation with glutaraldehyde was assessed, as well as the use of gelatin in the presence of celite, glass and silica. The highest immobilization yields were obtained when the pectinmethylesterase was immobilized in concanavalin A Sepharose 4B (81.7%) and in gelatin‐water (78.0%). Copyright © 2004 Society of Chemical Industry 相似文献
126.
An existing extensive database on the isothermal and thermomechanical fatigue behaviour of high-temperature titanium alloy
EVII 834 and dispersoid-strengthened aluminum alloy X8019 in SiC particle-reinforced as well as unreinv conditions was used
to evaluate both the adaptability of fracture mechanics approaches to TMF and the resulting predictive capabilities of determining
material life by crack propagation consideration. Selection of the correct microstructural concepts was emphasised and these
concepts were, then adjusted by using data from independent experiments in order to avoid any sort of fitting. It is shown
that the cyclic /-integral (δJeff concept) is suitable to predict the cyclic lifetime for conditions where the total crack propagation rate is approximately
identical to pure fatigue crack growth velocity. In the case that crack propagation is strongly affected by creep, the creep-fatigue
damage parameter δCF introduced by Riedel can be successfully applied. If environmental effects are very pronounced, the accelerating influence
of corrosion on fatigue crack propagation can no longer implicitly be taken into account in the fatigue crack growth law.
Instead, a linear combination of the crack growth rate contributions from plain fatigue (determined in vacuum) and from environmental
attack is assumed and found to yield a satisfactory prediction, if the relevant corrosion process is taken into account. 相似文献
127.
The photonic quantum ring (PQR) laser is a three dimensional whispering gallery (WG) mode laser and has anomalous quantum wire properties, such as microampere to nanoampere range threshold currents and √T‐dependent thermal red shifts. We observed uniform bottom emissions from a 1‐kb smart pixel chip of a 32×32 InGaAs PQR laser array flip‐chip bonded to a 0.35 µm CMOS‐based PQR laser driver. The PQR‐CMOS smart pixel array, now operating at 30 MHz, will be improved to the GHz frequency range through device and circuit optimization. 相似文献
128.
Sungmoon Jung Jamshid Ghaboussi Soon-Duck Kwon 《Canadian Metallurgical Quarterly》2004,130(11):1356-1364
A new method of estimating flutter derivatives using artificial neural networks is proposed. Unlike other computational fluid dynamics based numerical analyses, the proposed method estimates flutter derivatives utilizing previously measured experimental data. One of the advantages of the neural networks approach is that they can approximate a function of many dimensions. An efficient method has been developed to quantify the geometry of deck sections for neural network input. The output of the neural network is flutter derivatives. The flutter derivatives estimation network, which has been trained by the proposed methodology, is tested both for training sets and novel testing sets. The network shows reasonable performance for the novel sets, as well as outstanding performance for the training sets. Two variations of the proposed network are also presented, along with their estimation capability. The paper shows the potential of applying neural networks to wind force approximations. 相似文献
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