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991.
992.
A statement concerning the manner of the wearing away of tank blocks, factors affecting such wear, and detailed studies of surfaces of used tank blocks.  相似文献   
993.
994.
Does the presence of others facilitate or inhibit emotional expression? Female "senders" (n?=?45) viewed 12 emotionally loaded slides either alone or with another sender while responses were secretly videotaped. In Study 1, 14 "receivers" guessed the type of slide viewed by dyads more accurately (n?=?.366). In Study 2, 42 receivers viewed 10 senders with friends, 10 with strangers, and 10 alone. One dyad member was covered so that only 1 sender was visible. Analysis revealed significant effects of condition (alone, friend, or stranger; n?=?.456), slide type (sexual, scenic, unpleasant, or unusual; n?=?.325), and the Condition?×?Slide Type interaction (n?=?.350). Strangers had overall inhibitory effects on others. Thus, both social facilitation and inhibition of expression occurred on the basis of the emotional stimulus and personal relationship involved. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
995.
A comparison has been made of the behaviour in the oxidative coupling of methane of the oxides of Sm, Dy, Gd, La and Tb with that of a Li/MgO material. All but the Tb4O7 (which gave total oxidation) were found to give higher yields than the Li/MgO material at temperatures up to approaching 750°C but the Li/MgO system gave better results at higher temperatures. The cubic structure of Sm2O3 was found to be responsible for its good performance while the monoclinic structure was relatively inactive and unselective. The addition of Na or Ca to cubic Sm2O3 gives a higher optimum C2 yield than that of unpromoted Sm2O3. Sm2O3 and Ca/Sm2O3 catalysts are more stable than Li/MgO, Li/Sm2O3 or Na/Sm2O3. The addition of Li or Na to Sm2O3 causes the structure to change from cubic to monoclinic; the deactivation of the Na/Sm2O3 catalysts is caused by a loss of Na coupled with the formation of the monoclinic form of Sm2O3.  相似文献   
996.
BACKGROUND: The effects of reperfusion after coronary occlusion on transmural remodeling of the ischemic region early and late after nontransmural infarction must importantly affect the recovery of regional function. Accordingly, analysis of local volume and three-dimensional strain was performed using a finite element method to determine regional remodeling. Systolic and remodeling strains were measured using radiographic imaging of three columns (approximately 1 cm apart) of four to six gold beads implanted across the left ventricular posterior wall in 6 dogs. METHODS AND RESULTS: After a control study, infarction was produced by 2 to 4 hours of proximal left circumflex coronary artery occlusion followed by reperfusion. Follow-up studies were performed at 2 days, 3 weeks, and 12 weeks with the dogs under anesthesia and in closed-chest conditions. Biplane cineradiography was performed to obtain the three-dimensional coordinates of the beads. At 2 days, end-systolic strains were akinetic with loss of normal transmural gradients of shortening and thickening. Remodeling strains (RS) were determined by use of a nonhomogeneous finite element method by referring the end-diastolic configuration during follow-up studies to its control state at matched end-diastolic pressures and heart rates. Tissue volume at 2 days increased substantially, more at the endocardium (30 +/- 7%) than at the epicardium (5 +/- 12%, P < .01); the increase was associated with an average RS in the wall-thickening direction of 0.18 +/- 0.15 (P < .01) with all other RS near zero. At 12 weeks systolic function partially recovered, with normal wall thickening in the epicardium (radial strain, 0.081 +/- 0.056 [control] versus 0.113 +/- 0.088 [12 weeks]) but with dysfunction in the endocardium (0.245 +/- 0.108 [control] versus 0.111 +/- 0.074 [P < .01] [12 weeks]). This inability of the inner wall to recover function may be related to increased transmural torsional shear and negative longitudinal-radial transverse shear in the inner wall. Volume loss occurred at 12 weeks in the endocardium (-36 +/- 16%) corresponding to transmural gradients in longitudinal RS and both transverse shear RS. Negative longitudinal RS was greater at the endocardium (-0.20 +/- 0.10) than at the epicardium (-0.06 +/- 0.05, P < .01). CONCLUSIONS: These results indicate the presence of marked subendocardial edema 2 days after reperfusion following 2 to 4 hours of coronary occlusion. At 3 months after reperfusion, however, there was volume loss in the inner wall due to shrinkage along the myofiber direction with reduced transmural function and loss of longitudinal shortening, while both tissue volume and function recovered completely in the outer wall.  相似文献   
997.
Bibby  G.W. Ross  J.N. 《Electronics letters》1984,20(4):182-183
Chemical reactions in a Ge-P-silicate optical fibre exposed to hydrogen at 100 bar and 150°C for times up to 120 h are studied by Raman spectroscopy. Hydride and hydroxyl groups are formed, as Si-H and P-OH. The reaction kinetics are consistent with a defect-related mechanism. The saturation concentration of hydroxyl is about 103 ppm.  相似文献   
998.
Thirty-one patients with globus sensation were examined by dual probe pH manometry and videolaryngoscopy to investigate the role of gastroesophageal reflux disease in association with globus. Abnormal laryngeal findings, which included grossly abnormal and subtle changes, were seen in 17 patients. These findings included pharyngeal erythema (12 patients), interarytenoid pachydermia (11), laryngeal edema (11), arytenoid erythema (9), and thick mucus (3). Twenty-one of the 31 pH probe studies showed gastroesophageal reflux disease (14 grossly abnormal, 6 borderline abnormal) with Johnson and DeMeester composite scores for the distal probe. There was no correlation between the upright and supine position, nor was there correlation between positive laryngeal findings and a positive pH probe study. We conclude that globus sensation is often a nonspecific symptom of laryngopharyngeal irritation in which gastroesophageal reflux disease plays a significant role. Combining careful laryngoscopic examination with pH probe studies can help to differentiate between patients with organic pathology caused by gastroesophageal reflux disease and patients with other nonspecific laryngopharyngeal disorders.  相似文献   
999.
Four experiments examined how people make inductive inferences using categories. Subjects read stories in which 2 categories were mentioned as possible identities of an object. The less likely category was varied to determine if people were using it, as well as the most likely category, in making predictions about the object. Experiment 1 showed that even when categorization uncertainty was emphasized, subjects used only 1 category as the basis for their prediction. Experiments 2–4 examined whether people would use multiple categories for making predictions when the feature to be predicted was associated to the less likely category. Multiple categories were used in this case, but only in limited circumstances; furthermore, using multiple categories in 1 prediction did not cause subjects to use them for subsequent predictions. The results increase the understanding of how categories are used in inductive inference. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
1000.
Focused on how clinicians combine symptom information about narcissistic personality disorder (NPD) to make a diagnosis. A sample of 59 psychiatrists and clinical psychologists were asked to read and diagnose 20 case histories of which 6 cases had criteria for NPD embedded as sentences. The number of criteria and the face validity of the criteria were varied across case histories. Three models of how criteria might be combined to form a diagnosis were compared: the polythetic model, the additive model, and the weighting model. The results were most consistent with the weighting model. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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