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91.
Barefoot John C.; Haney Thomas L.; Simpson Sallie W.; Blumenthal James A.; Williams Redford B. Jr. 《Canadian Metallurgical Quarterly》1990,2(4):483
The Structured Interview (SI) method of assessing Type A behavior pattern (TABP) relies on the S's voice stylistics, whereas the Jenkins Activity Survey (JAS) relies on response content. It was hypothesized that depression would affect SI assessments by masking voice stylistics but would have no impact on JAS assessments. The SI, JAS, and the Zung Self-Rating Depression Scale were administered to 2,066 coronary patients. As predicted, there was a negative relationship between depression and SI-assessed TABP and a modest positive relationship between depression and JAS-assessed TABP. Analysis of Type A components revealed that loudness, explosive speech, and intensity of hostility differed between depressed and nondepressed patients. Affective states that influence expressivity appear to produce misclassifications using SI assessments, especially in clinical samples. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
Herman Steve; Blumenthal James A.; Babyak Michael; Khatri Parinda; Craighead W. Edward; Krishnan K. Ranga; Doraiswamy P. Murali 《Canadian Metallurgical Quarterly》2002,21(6):553
Psychosocial factors predicting treatment dropout or failure to benefit from treatment were identified in a randomized trial of exercise therapy and pharmacotherapy for major depression. One hundred fifty-six men and women over age 50 diagnosed with major depressive disorder were assigned to a 16-week program of aerobic exercise, medication (sertraline), or a combination of exercise and medication. Thirty-two patients (21%) failed to complete the program and were considered treatment "dropouts." At the end of 16 weeks, 83 patients (53%) were in remission; the remaining patients not in remission were considered treatment "failures." Baseline levels of self-reported anxiety and life satisfaction were the best predictors of both patient dropout and treatment success or failure across all treatment conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Simultaneous wavelength conversion and high-speed wavelength switching has been demonstrated using a multisection grating-assisted coupler sampled reflector laser. A high-output extinction ratio (>20 dBm) over a 30-nm wavelength range was observed. The 10-Gb/s data was switched between different output wavelengths at a 2.5-Gb/s rate and transmitted over 50 km of dispersion-shifted fiber with a small measured power penalty (<2 dB) 相似文献
94.
The effects of gain saturation, gain asymmetry, and pump/probe depletion on the conversion efficiency of four-wave mixing (FWM) in semiconductor optical amplifiers are studied analytically and numerically. The power dependence of FWM coupling coefficients and ultrafast relaxation-related gain mechanisms are included in the model. By studying the FWM efficiency in the transition from unsaturated to strongly saturated regions, it is seen that gain asymmetry results in deviation from small-signal models when the pump-probe detuning and pump powers are small. At high pump injection or gain conditions, it is also shown that the small-signal model breaks down even for relatively large detuning frequencies. Probe depletion is also seen to be critical under saturated conditions and an upper bound is derived for ranges of input pump power, pump-probe detuning, and gain for a given amplifier under which the small-signal model is valid 相似文献
95.
Zhaoyang Hu K. Nishimura Hsu-Feng Chou L. Rau M. Usami J.E. Bowers D.J. Blumenthal 《Photonics Technology Letters, IEEE》2004,16(12):2640-2642
An injection-locking traveling-wave electroabsorption modulator-based ring oscillator is demonstrated to perform optical clock recovery and simultaneous reshaping of 40-Gb/s optical packets. The transient response analysis and experimental results show strong injection and short loop length reduce the locking time to within 0.3 /spl mu/s. The recovered packet optical clock has 532-fs timing jitter. 相似文献
96.
97.
Blood lead levels and risk factors for lead poisoning among children in Jakarta,Indonesia 总被引:3,自引:0,他引:3
Albalak R Noonan G Buchanan S Flanders WD Gotway-Crawford C Kim D Jones RL Sulaiman R Blumenthal W Tan R Curtis G McGeehin MA 《The Science of the total environment》2003,301(1-3):75-85
The phase-out of leaded gasoline began in Jakarta, Indonesia on July 1, 2001. We evaluated mean blood lead levels (BLLs) and the prevalence of elevated BLLs of Jakarta school children and assessed risk factors for lead exposure in these children before the beginning of the phase-out activities. The study involved a population-based, cross-sectional blood lead survey that included capillary blood lead sampling and a brief questionnaire on risk factors for lead poisoning. A cluster survey design was used. Forty clusters, defined as primary schools in Jakarta, and 15 2nd- and 3rd-grade children in each cluster were randomly selected for participation in the study. The average age of children in this study was 8.6 years (range 6-12) and the geometric mean BLL of the children was 8.6 microg/dl (median: 8.6 microg/dl; range: 2.6-24.1 microg/dl) (n=397). Thirty-five percent of children had BLLs > or =10 microg/dl and 2.4% had BLLs > or =20 microg/dl. Approximately one-fourth of children had BLLs 10-14.9 microg/dl. In multivariate models, level of education of the child's primary caregiver, water collection method, home varnishing and occupational recycling of metals, other than lead, by a family member were predictors of log BLLs after adjustment for age and sex. BLLs of children who lived near a highway or major intersection were significantly higher than those of children who lived near a street with little or no traffic when level of education was not included in the model. Water collection method was a significant predictor of BLLs > or =10 microg/dl after adjustment for age and sex. BLLs in children in this study were moderately high and consistent with BLLs of children in other countries where leaded gasoline is used. With the phase-out of leaded gasoline, BLLs of children in Jakarta are expected to rapidly decline as they have in other countries that have phased lead out of gasoline. 相似文献
98.
Herman Blumenthal Ronald Silverman 《JOM Journal of the Minerals, Metals and Materials Society》1955,7(2):317-322
It was found that despite the similarity of chemical analyses of different titanium carbides used as base materials for cermets, the physical properties, especially transverse-rupture strengths, of test bars were different. Hence this metallographic study attempts to link physical properties to micro-structures. It is shown that microstructure, grain shape, and grain growth are functions of three interrelated factors: 1—powder production procedure, 2—surface conditioning of the particles, and 3—impurities either contained in the original powder or acquired during ball milling. An explanation is offered for the “coring effect,” long observed, but heretofore of unknown origin. The explanation is based on assumption of an oxide film and on chemical analyses which substantiate these findings. 相似文献
99.
Rosenberg Erika L.; Ekman Paul; Jiang Wei; Babyak Michael; Coleman R. Edward; Hanson Michael; O'Connor Christopher; Waugh Robert; Blumenthal James A. 《Canadian Metallurgical Quarterly》2001,1(2):107
The authors examined whether facial expressions of emotion would predict changes in heart function. One hundred fifteen male patients with coronary artery disease underwent the Type A Structured Interview, during which time measures of transient myocardial ischemia (wall motion abnormality and left ventricular ejection fraction) were obtained. Facial behavior exhibited during the ischemia measurement period was videotaped and later coded by using the Facial Action Coding System (P. Ekman & W. V. Friesen, 1978). Those participants who exhibited ischemia showed significantly more anger expressions and nonenjoyment smiles than nonischemics. Cook–Medley Hostility scores did not vary with ischemic status. The findings have implications for understanding how anger and hostility differentially influence coronary heart disease risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
Buck J.A. Owen H.W.L. III Uyemura J.P. Verber C.M. Blumenthal D.J. 《Education, IEEE Transactions on》1999,42(2):138-143
A senior-level design laboratory course is described, in which an optical fiber communication network is expanded or improved by successive generations of students. In this evolutionary approach, student teams base their work on the final written reports of students in previous course offerings. In addition to its primary goal of providing a high-level technical experience, the course requires multidisciplinary teamwork and provides incentive for the development of effective oral and written communication skills. Results of four offerings of the course are presented 相似文献