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71.
Performed 2 vibrotactile reaction time (RT) experiments, using 32 strongly dextral undergraduates to determine if (1) Ss attention toward/away from the operating hand effected RT and (2) there was an interaction with hand-hemispace and spatial compatibility. In Exp I, 16 Ss were administered a 250 Hz vibratory stimulus to the forefinger of a hand and were required to depress a switch as soon as the stimulus was felt. Hemispace of the stimulated hand was varied and head turns were recorded. In Exp II, 16 Ss were presented with stimuli to the left and the right hand and Ss looked at 1 hand for a block of trials. Results suggest that vibrotactile asymmetries may stem from differences in ability to hold covert attention in a number of spatial locations. It is suggested that overt and covert attention play different mediating roles in performance asymmetries, both at the hemispatial level and in classical anatomical connectivity paradigms of visual field and ear of entry. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
72.
This note ushers in an exciting (though exacting) new science: thesis interpretation. Thesis interpretation rests on the assumption that writing a PhD thesis in psychology involves the same psychic processes as responding to a Rorschach inkblot. The thesis--as an object--may be used to make psychodynamic inferences about its author. Two experiments were designed to test the hypothesis that anal compulsivity--as indicated by the length of thesis (including appendixes)--will be negatively correlated with future productivity--as indicated by number of publications. The correlation, although not significant, was in the predicted direction. It is hoped that these experiments illustrate the potential usefulness of thesis interpretation and will encourage other psychologists to investigate other variables with this powerful new tool. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
73.
A large number of between-Ss expectancy theory studies have correlated measures of employee motivation (force) to perform with measures of effort and performance. The results of these studies vary considerably. A statistical review of the studies was conducted to determine the extent to which the variance explained (the dependent variable) was a function of various characteristics of the effort and performance and of the force-to-perform measures (the independent variables). There were 160 observations, derived from 32 studies. With the use of multiple regression analysis it was found that variance explained in these studies was greater when (a) self-report or quantitative measures of effort and performance were used rather than evaluations of these variables by someone other than the S; (b) 10–25 outcomes were included in the force measure rather than a greater or smaller number of outcomes; (c) outcome valence was numerically scaled with positive numbers only, and the scale values were described in terms of desirability rather than importance; and (d) the force measure contained either no assessment of expectancy or an assessment that confounded expectancy and instrumentality. These variables accounted for 42% of the variance in the results obtained in the studies reviewed. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
74.
Quasi-static recording experiments employing a hybrid single-pole-type write head and a vertical magnetoresistive transducer (MRT) read head are presented. The MRT is shown to be able to measure asymmetries of the remanent magnetization of transitions recorded in perpendicular and longitudinal media. The effects of varying the write field angle by adjusting the write shim placement with respect to the auxiliary pole is shown to be useful in determining the resultant remanent magnetization. Dynamic recording responses correlate with the quasi-static measurements. A model of recorded transitions is presented which combines in-plane arctangent and vertical complementary arctangent remanent magnetization distributions.  相似文献   
75.
20 overweight and 20 normal weight female undergraduates underwent habituation, classical conditioning, and extinction of the GSR. Overweight Ss were consistently more responsive to the CS (tone) during all 3 phases of the study and were somewhat more responsive to the UCS (shock). Rates of response attenuation and enhancement, however, were not different during any phase. Results are generally consistent with research which demonstrates that overweight Ss are more externally stimulus bound than normals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
76.
The dissolution of a single stationary bubble held in place by a horizontal plate is commonly observed experimentally. For several decades the standard approach to the analysis of such dissolution data has been to apply a correction factor of ln(2)=0.69 to the Epstein-Plesset equation for an isolated bubble. In this paper, the transport equations for a stationary bubble touching a plate are solved numerically for the common case where the flow field caused by the change in system volume as the bubble dissolves can be neglected. It is found that the total bubble lifetime is not well characterised by the use of the ln(2) factor. However, in most experimental situations, the initial stages of bubble dissolution are not captured. For low gas solubilities the use of a correction factor of 0.69 to the Epstein-Plesset equation is appropriate once the initial transients have dissipated. The correction factor varies from 0.69 to 0.77 across the full range of situations described in this paper. The mathematical model is validated by comparison to experimental data.  相似文献   
77.
The purpose of this study was to establish the validity of the INT-dehydrogenase test for determining the biochemical activity of actinomycete foams. Parallel measurements of INT-dehydrogenase activity, adenosine triphosphate and oxygen uptake rate were made on foam samples collected from three different activated sludge plants over a period of several months. Activity levels of actinomycete foams measured in this study were found to be comparable to those of activated sludge as reported in the literature. Good-to-excellent correlations (r2 > 0.87) were found between INT-dehydrogenase activity and the alternative parameters. Precision of all assays tested was comparable. The INT-dehydrogenase test can therefore be used in lieu of ATP or oxygen uptake rate assays without sacrifice in either the reliability or reproducibility of results obtained.  相似文献   
78.
Recent studies have shown that the tumor promoter 12-O-tetradecanoyl-phorbol-13-acetate (TPA) stimulates protein kinase C (PKC), whereas the ether-linked phospholipid 1-O-octadecyl-2-O-methyl-rac-glycerol-3-phosphocholine (ET-18-OCH3) inhibits PKC activity in vitro. Therefore, the antitumor effects of ET-18-OCH3 could be due to its inhibition of PKC activity and the effects of tumor promotion. TPA stimulates arachidonic acid release, prostaglandin synthesis, phosphatidylcholine synthesis and the degradation of phosphatidylcholine by phospholipase C in Madin Darby canine kidney (MDCK) cells. Therefore, we have determined the effects of ET-18-OCH3 on these consequences of TPA stimulation. Preliminary experiments determined that ET-18-OCH3 inhibited PKC partially purified from MDCK cells by ion-exchange chromatography on DEAE-cellulose. In addition, ET-18-OCH3, inhibited the TPA-stimulated phosphorylation of a 40,000-dalton protein in intact MDCK cells. These data indicate that ET-18-OCH3 is an effective inhibitor of PKC activity in MDCK cells. In addition, ET-18-OCH3 was found to inhibit arachidonic acid release and prostaglandin synthesis. The inhibition of prostaglandin synthesis appears to be secondary to inhibition of arachidonic acid release, since ET-18-OCH3 does not inhibit TPA-stimulated synthesis of prostaglandin H synthase or the activity of the enzyme directly (Parker, J., Daniel, L. W., and Waite, M. [1987]J. Biol. Chem. 262, 5385–5393). ET-18-OCH3 also inhibits TPA-stimulated phosphatidylcholine synthesis and phosphatidylcholine degradation by phospholipase C. These data provide evidence that the antineoplastic ether lipids inhibit the biochemical effects of the tumor promoter TPA in intact cells and indicate that this inhibition may have a role in their biological activities.  相似文献   
79.
A 1986 survey of 2,100 American Psychological Association (APA) members, to which 78% responded, showed that members belonged to APA for varied reasons and that scientists, scientist-practitioners, and practitioners shared few common rationales for maintaining their membership. Most members belonged to other organizations in addition to APA, and less than 50% of those chose APA as their most important organizational membership. Whereas the APA Monitor and APA journals received a strong endorsement from respondents, the publication of Psychology Today was clearly controversial. The cost and size of the convention also were sources of dissatisfaction. Recommended changes in convention format included scheduling more keynote addresses and establishing area-specific conventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
80.
In 5 single-S experiments, depressed mood and corrugator EMG were measured while 5 female depressed psychiatric hospital day-clinic patients thought happy and unhappy thoughts. Results show that mood was significantly more depressed after unhappy thoughts for all Ss. During the 2nd half of the thought periods, corrugator EMG was higher in the unhappy condition than in the happy condition for all Ss, significantly so for all but one. Significant positive correlations between depressed mood and corrugator EMG were obtained in all Ss. Findings are discussed in relation to cognitive theories of depression and to the usefulness of corrugator EMG as an index of depressed mood. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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