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41.
Expressions for the bulk modulus and its first and second pressure derivatives for group I–VII, II–VI, III–V and IV–IV semiconductor binary compounds are derived using an ab initio pseudopotential approach to the total crystal energy within the framework of local density functional formalism. The computed results are very close to the available experimental data.  相似文献   
42.
A phase transition of MgS under high pressure is investigated using a first-principles method. It is found from energy-volume calculations that the rock-salt (B1) phase of MgS transforms into a FeSi-type (B28) phase at 143?GPa. The calculated ground-state parameters in the B1 phase are in excellent agreement with available experimental and theoretical data. Ab initio phonon calculations are also performed to investigate the structural behaviour of MgS under high pressure. An unstable transverse acoustic mode and a phase transition from B1 to B28 phase at ~143.7?GPa driven by this soft mode are predicted. The B28 structure of MgS is stable up to 350?GPa according to lattice dynamics calculations.  相似文献   
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The study investigated the effect of relaxation therapy on arterial blood pressure of Patients with essential hypertension. Ten known essential hypertension patients (males = 3; females = 7, age range 41–70, mean age 57.2 years, SD = 9.93 years) were sampled randomly from Medical outpatient department of the State owned University teaching Hospital in Ebonyi State South East, Nigeria. These Participants were exposed to 30 minutes relaxation therapy and their blood pressures were taken before and after the treatment. Using matched t test to compare baseline and post treatment scores, result showed that relaxation therapy progressively decreased both diastolic and systolic blood pressure readings of the Participants. The study concluded that Relaxation therapy can transiently lower the systolic and diastolic blood pressure.  相似文献   
44.
Victim profiles of sexual coercion might differ based on the type of perpetrator that initiates the coercion—namely, a stranger versus a dating partner. Some victims experience coercion from both types of perpetrators—referred to here as “double victims.” Survey data from 2,322 undergraduates at two relatively large U.S. universities in the Midwest and Southeast revealed in a multinomial logistic regression analysis that victims of distinct types of perpetrators had unique predictors as part of their overall profiles. Background characteristics associated with each type were identified. In comparison to nonvictims, a profile of double victims emerged—a White female who had been abused as a child, who had cohabited with a partner, used alcohol or drugs, had been emotionally abused by a partner, had lied to a partner, used the Internet to find a partner, had dated interracially, and had engaged in sex in a noncommitted relationship. Implications and limitations of these findings are included in the discussion.  相似文献   
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This study focuses on the effect of restrictive information display on decision performance. Specifically the study examines whether two‐channeled and one non‐channeled computerized information display systems result in significant differences in decision accuracy. The two‐channeled information display systems are designed to encourage two general information processing patterns commonly observed in the experimental literature examining multi‐alternative, multi‐attribute choice decisions: information processing by alternative and information processing by attribute. An information display program was developed which used restrictive information display to operationalize the channeled versus non‐channeled manipulation. Channeling was implemented either by displaying information only by alternative or by displaying information only by attribute. The task was an operations scheduling problem that subjects completed under three levels of time pressure. The results indicate statistically significant effects on decision accuracy for both the type of information display and time pressure manipulations. The highest decision accuracy was observed when information was displayed by alternative and when subjects were under highest levels of time pressure. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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Abstract: Yaezawa and Yoshida's (1981 ) findings on the effects of an intrusion on personal space were reinvestigated. Thirty-five female students were confronted with the approach of a male stranger, and blood pressure (BP) and heart rate (HR) were monitored. Throughout the model's approach, HR showed a significant triphasic change (an initial decrease, a subsequent increase, and then a secondary decrease), whereas subjective feelings of anxiety and tension showed significant, gradual increases. These trends were similar to those of Yaezawa and Yoshida's . Nonetheless, their explanation that the triphasic change in HR reflected once hightened and then relieved tension, which was incongruent with the subjective ratings, seemed questionable. As the BP elevated to a moderate degree in spite of the modest HR changes, total peripheral resistance must have been increasing during the model's approach. Blood pressure elevations via this sort of hemodynamic pressor mechanisms have often been reported when a person can only tolerate passively during exposure to stress. This seems to be the case in an intrusion on personal space.  相似文献   
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The goal of the present study was to explore how anger reduction via a single session of meditation might be measured using psychophysiological methodologies. To achieve this, 15 novice meditators (Experiment 1) and 12 practiced meditators (Experiment 2) completed autobiographical anger inductions prior to, and following, meditation training while respiration rate, heart rate, and blood pressure were measured. Participants also reported subjective anger via a visual analog scale. At both stages, the experienced meditators’ physiological reaction to the anger induction reflected that of relaxation: slowed breathing and heart rate and decreased blood pressure. Naïve meditators exhibited physiological reactions that were consistent with anger during the pre-meditation stage, while after meditation training and a second anger induction they elicited physiological evidence of relaxation. The current results examining meditation training show that the naïve group’s physiological measures mimicked those of the experienced group following a single session of meditation training.  相似文献   
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