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991.
May Douglas R.; Schwoerer Catherine E.; Reed Kendra; Potter Paul 《Canadian Metallurgical Quarterly》1997,2(1):11
A field survey of 180 municipal government office employees (82% women, 21–75 years old) investigated the potential moderating effects of internal health locus of control (HLOC) and self-efficacy on employees' reactions to ergonomic job design. Internal HLOC moderated the associations between ergonomic job design and somatic complaints and turnover intentions, and, to a lesser extent, job satisfaction. Self-efficacy moderated the associations between job design and job satisfaction, somatic complaints, and, to a lesser extent, persistent pain. Employees with low self-efficacy or low internal HLOC were influenced more by their physical job conditions than those with high self-efficacy or high internal HLOC. Implications for the ergonomic design of offices are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Catherine Galey Véronique Dilé Dominique Gatel Louis Herremans Jacques Cavard 《臭氧:科学与工程》2004,26(3):247-256
Intensive pilot studies were performed to study the impact of ozone dose (0.6 to 3.5 mg/L), pH (6.0 to 7.5), and contact time (12 to 38 min) on bromate (BrO3) formation, for different sand-filtered water qualities from the Neuilly-sur-Marne Treatment Plant (COT = 1.3 to 2.2 mg/L, TAC = 190 to 230 mg CaCO3, [Br?] = 25 to 50 μg/L, and T = 5°C to 26°C). Whatever the water quality studied, the main factors influencing bromate formation were ozone dose, pH, and a cross factor between them. Bromate formation was shown to be proportional to bromide concentration, and to increase only slightly with temperature, depending on the ozone dose and the pH. As on the contrary temperature has an important impact on disinfection, especially when considering Cryptosporidium inactivation, resolving the challenge of ensuring disinfection while limiting bromate formation was shown to be quite easily achievable, at intermediate temperature, and with more stringent conditions at high temperature (because of bromate formation) or at low temperature (because of disinfection). 相似文献
993.
Christian Grailla Michel Bartholir Catherine Gauthier Alain Guyot 《Polymer International》2004,53(5):536-540
A rigid polyimide (PI) was dissolved in acrylic monomers (methyl methacrylate, n‐butyl acrylate) as a hydrophobe to form miniemulsions stabilized by a mixture of sodium dodecyl sulfate and Triton®, with droplets size in the range 100–300 nm, and PI concentration up to about 30% by weight, which corresponds to its limit of solubility. Upon polymerization initiated with ammonium persulfate, the particle size tends to decrease to the range 80–250 nm. From these hybrid latexes, clear yellowish films were obtained with two glass transitions: one close to that of polybutylacrylate (Tg = ?50 °C) and the second between 15 and 40 °C, depending on PI concentration. PI causes a reinforcement of the mechanical properties at room temperature. This reinforcement is enhanced through an appropriate thermal treatment. Copyright © 2004 Society of Chemical Industry 相似文献
994.
Design guidelines for wireless sensor networks: communication, clustering and aggregation 总被引:14,自引:0,他引:14
When sensor nodes are organized in clusters, they could use either single hop or multi-hop mode of communication to send their data to their respective cluster heads. We present a systematic cost-based analysis of both the modes, and provide results that could serve as guidelines to decide which mode should be used for given settings. We determine closed form expressions for the required number of cluster heads and the required battery energy of nodes for both the modes. We also propose a hybrid communication mode which is a combination of single hop and multi-hop modes, and which is more cost-effective than either of the two modes. Our problem formulation also allows for the application to be taken into account in the overall design problem through a data aggregation model. 相似文献
995.
The role of the central nucleus of the amygdala on olfactory heart rate conditioning in the infant rat was investigated. The conditioned stimulus (CS) consisted of a 10-s presentation of grape juice odor that was immediately followed by a 0.5-s, 0.35-mA subcutaneous shock. A sensitization control group was also run. Three days prior to testing, Ss received either bilateral electrolytic lesions of the central nucleus of the amygdala, sham lesions, or were left unperturbed. Results show that damage to the central nucleus of the amygdala severely impaired olfactory heart rate conditioning but that it had no deleterious effect on the heart rate orienting response to that stimulus or on the heart rate unconditioned response (UCR) to shock. Results are analogous to those in previous research on auditory heart rate conditioning and suggest that the central nucleus of the amygdala may constitute a necessary stage in the transduction of the CS into a cardiac conditioned response (CR) regardless of sensory modality. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Under certain conditions, some microorganisms are able to synthesize surface active compounds called biosurfactants (BS), which reduce the surface tension of water. BS characteristics depend on which microorganism produce them and therefore, on the microorganism culture conditions (temperature, pH, C, N-source,…). Numerous applications are known for these biomolecules, such as cleaning, bioremediation, and their use as a detergent, or in cosmetic formulations.Recently, a large amount of literature has been edited on the influence of BS on the interactions between pathogenic bacteria and inert surfaces. It has been shown that the modifications of surface properties by the adsorption of BS can reduce microbial adhesion.Some other studies on chemical surfactants have shown that the adsorption of surface-active compounds plays a major role in corrosion; they are indeed used as an interesting corrosion inhibition tool. Therefore, it seems very interesting to study the impact of BS as environment-friendly (since biological and biodegradable) corrosion inhibitors.In the present work, an attempt was made to study the corrosion behaviour of AISI 304 stainless steel in presence of BS produced by a Gram-negative bacteria, Pseudomonas fluorescens (Pf495). Corrosion tests were achieved on several surface oxidation states. The surface morphology of the corroded specimens was investigated using SEM. 相似文献
997.
Catherine O. Bendure 《Information Systems Management》1991,8(4):50-56
Computer-aided software engineering (CASE) methodology and tools play an important role in the development of information systems and in the future direction of CASE. The amount of available information on this topic can be overwhelming. This article presents guidelines on selecting tools and a methodology based on the experience of the systems development team at Howard Hughes Medical Institute (HHMI), where CASE has been successfully implemented. 相似文献
998.
Schmidt Louis A.; Cote Kimberly A ; Santesso Diane L.; Milner Catherine E. 《Canadian Metallurgical Quarterly》2003,3(4):401
Electroencephalogram (EEG) alpha (8-12 Hz) asymmetries were collected from the mid-frontal and central regions during presleep wakefulness and Stage 1, Stage 2, and rapid eye movement (REM) sleep in 11 healthy right-handed participants who were free of psychiatric, neurological, and sleep problems. The authors found significant correlations between presleep wakefulness and different stages of sleep in the frontal, but not central, EEG alpha asymmetry measure. The strongest correlation was between presleep waking and REM sleep, replicating and extending relation earlier work to a normal population. The high degree of association between presleep waking and REM sleep may be a result of high cortical activation common to these states and may reflect a predisposition to different styles of emotional reactivity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Kay Leslie M.; Lowry Catherine A.; Jacobs Heather A. 《Canadian Metallurgical Quarterly》2003,117(5):1108
Odor mixture perception can be configural (the mixture is qualitatively different from the components) or elemental (the components are recognizable). Some have argued that configural properties are dependent on chemical similarity and possible overlap at the receptor level. The authors show that a binary mixture in which both components activate the same receptor (17) has a configural odor, whereas a mixture that suppresses overlap has elemental odor properties. Rats trained to recognize mixtures of citronellal and octanal (strong 17 agonists) in many ratios rarely recognize the components, supporting configural representation of the odor mixture. However, when trained to recognize mixtures of citral (partial 17 agonist, inhibitor) and octanal, rats recognize 1 or both components over a wide range of ratios. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
This research extends previous work indicating that individuals are more effective at regulating their behavior when they are in goal-congruent contexts by examining whether individuals particularly need concrete goal-relevant situational affordances once they are in these broadly affirming contexts. Specifically, the authors explore this issue by using the broad context of steady dating relationships (i.e., intimacy-relevant contexts), and considering the role of both intimacy goals and intimacy-affording daily life situations in producing relationship satisfaction and maintenance over time. Results indicate that those with a strong focus on intimacy experience considerable relationship satisfaction regardless of whether they spend time in daily life situations that facilitate intimacy, whereas those without such a focus depend for satisfaction on the presence of intimacy-conducive situations (e.g., time alone with one's partner, or social support from one's partner). Discussion focuses on the theoretical implications of these findings for the Person x Situation literature. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献