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81.
The data from indices measuring the concepts of ego-strength, need for achievement, and hysteria were factor-analyzed. The analysis produced 5 orthogonal dimensions, viz., neuroticism, intellectual flexibility, extraversion, other-orientation, and perseverance for achievement. These factors were then correlated with performance in a task which involved the memory of a Zeigarnik-type failure-stress experience. The factor related to striving for achievement and quality of recall of the experience of failure were highly correlated, with high need achievers reacting "obsessively" and low need achievers, "repressively" (as defined in the report). The results are discussed re: the theoretical implications of this and previous research. 25 refs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
An array phasing device is described which uses IF frequency multiplication and heterodyning to obtain a series of microwave signals at progressively related phase angles. The unique feature of this device is that it requires only one precision phase shifter for each direction of scan.  相似文献   
83.
The changes in matrix structure that occur during tempering of an Fe-0.2C martensite at 400° to 700°C have been investigated. Light and electron metallographic observations show that when tempered, the fine martensitic lath structure coarsens while retaining the elongated packet-lath morphology. The as-quenched hardness 504 Khn and total grain boundary area per unit volume 50,800 cm−1 decrease abruptly at the higher tempering temperatures and in seconds reach relatively stable values that decrease slowly with time. The decrease in low angle boundaries accounts for most of the initial grain boundary area change, while the large angle boundary component of total boundary area decreases gradually with tempering time. Recovery processes are responsible for the initial changes in matrix structure, and carbide boundary pinning suppresses recrystallization until grain growth dominates in the later stages of tempering.  相似文献   
84.
Photodarkening or partial photobleaching of photochromic solid media is described by means of an approximated analytical equation. The equation shows that the effective rate of the photochemical reaction is proportional to the square root of the final transmittance of the illuminated layer. The model is applied to describe the photodarkening of dichromated gelatin at 488 nm.  相似文献   
85.
86.
Objective: This study was designed to explore the acceptability, feasibility, and initial efficacy of a new shelter-based treatment for victims of intimate partner violence (IPV; i.e., Helping to Overcome PTSD through Empowerment [HOPE]). Method: A Phase I randomized clinical trial comparing HOPE (n = 35) with standard shelter services (SSS) (n = 35) was conducted. Primary outcome measures included the Clinician-Administered PTSD Scale (CAPS; D. D. Blake et al., 1995) and the Conflict Tactic Scales-Revised (M. A. Straus, S. L. Hamby, S. Boney-McCoy, & D. B. Sugarman, 1996). Participants were followed at 1-week, 3- and 6-months postshelter. Results: Participants reported HOPE to be credible and indicated a high degree of satisfaction with treatment. Only 2 women withdrew from treatment. Both intent to treat (ITT) and minimal attendance (MA) analyses found that HOPE treatment relative to SSS was significantly associated with a lower likelihood of reabuse over the 6-month follow-up period (OR = 5.1, RR = 1.75; OR = 12.6, RR = 3.12, respectively). Results of hierarchical linear model analyses found a significant treatment effect for emotional numbing symptom severity in the ITT sample, t(67) = ?2.046, p  相似文献   
87.
The influence of topologically close packed-phase (TCP-phase) precipitation on the γ/γ′ microstructure evolution of a single crystal superalloy has been studied. Four representative configurations of needle-shaped μ-phase particles observed in the MC2 alloy after creep deformation at 1050 °C/160 MPa have been selected.Finite element modeling was performed on the selected configurations using a crystal plasticity framework and a viscoplastic approach.The local calculated stress/strain fields in the vicinity of TCP-phase precipitates, especially stress concentration, allow an interpretation of the observed microstructural evolutions (γ′-precipitate orientation and thickness).Moreover, our numerical simulation brings a fruitful contribution to the understanding of the phenomenon often observed beyond needle-like μ-phase: the formation of a distorted γ/γ′ microstructure in lieu of the expected γ/γ′-rafted structure.  相似文献   
88.
Amphetamine (AMPH) inhibits uptake and causes release of dopamine (DA) from presynaptic terminals. AMPH can act on both vesicular storage of DA and directly on the dopamine transporter (DAT). To assess the relative importance of these two processes, we have examined the releasing actions of AMPH in mice with a genetic deletion of the DAT. The sequence of actions of AMPH has been determined by following the real time changes of DA in the extracellular fluid of intact tissue with fast scan cyclic voltammetry. In striatal slices from wild-type mice, AMPH causes a gradual (approximately 30 min) increase in extracellular DA, with a concomitant disappearance of the pool of DA available for depolarization-evoked release. Conversely, in slices from mice lacking the DAT, although a similar disappearance of electrically stimulated DA release occurs, extracellular DA does not increase. Similarly, microdialysis measurements of DA after AMPH in freely moving animals show no change in mice lacking the DAT, whereas it increases 10-fold in wild-type mice. In contrast, redistribution of DA from vesicles to the cytoplasm by the use of a reserpine-like compound, Ro4-1284, does not increase extracellular DA in slices from wild-type animals; however, subsequent addition of AMPH induces rapid (<5 min) release of DA. Thus, the DAT is required for the releasing action, but not the vesicle-depleting action, of AMPH on DA neurons, and the latter represents the rate-limiting step in the effects of AMPH. Furthermore, these findings suggest that in the absence of pharmacological manipulation, such as the use of amphetamine, endogenous cytoplasmic DA normally does not reach sufficient concentrations to reverse the DAT.  相似文献   
89.
As interference from thyroglobulin autoantibodies appears to have been overcome in new commercial thyroglobulin assays by the use of monoclonal antibodies, the need for thyroglobulin recovery tests became uncertain. Sera (n=45) from patients with differentiated thyroid carcinomas were selected on the basis of a thyroglobulin recovery value below 70% in the Dynotest Tg immunoradiometric assay (Brahms) routinely used in our laboratory. Serum thyroglobulin levels were then measured using three other commercial immunoradiometric assays: thyroglobulin ERIA (Pasteur), HTGK (Sorin) and ELSA HTG (Cis Bio International). Thyroglobulin autoantibodies were measured using the Thyrak assay (Brahms). Although many patients were thyroglobulin antibodies-negative (< 200 U/ml, n=26), most immunoradiometric assays failed to detect thyroglobulin in patients with evidence of recurrence. Low thyroglobulin values associated with low thyroglobulin recovery in thyroglobulin antibody-negative patients appear to be more biologically relevant than a single low thyroglobulin value, which can lead to lack of medical intervention. We conclude that the thyroglobulin recovery test is a prerequisite for the correct interpretation of serum thyroglobulin levels determined with immunoradiometric assays in the follow-up of thyroglobulin autoantibody-negative patients treated for differentiated thyroid carcinomas.  相似文献   
90.
In Experiment 1, 2 squirrel monkeys (Saimiri sciureus) were given choices between all possible pairs of the arabic numbers 0, 1, 3, 5, 7, and 9, with choice of any number yielding that number of pieces of peanut as a reward. Both monkeys learned to choose the larger number in all pairings and learned to choose the largest number within a set of 4 numbers. In Experiments 2–4, the monkeys were tested on problems in which they chose between pairs of stimuli containing 2 numbers versus 2 numbers, 1 number versus 2 numbers, and 3 numbers versus 3 numbers. Both monkeys showed a significant tendency to choose the stimulus that contained the largest sum. Various tests indicated that this effect could not be explained by choice of the stimulus with the largest single number, by avoidance of the stimulus with the smallest single number, or by experimenter cuing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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