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941.
942.
The prevention of major depression is an important research goal which deserves increased attention. Depressive symptoms and disorders are particularly common in primary care patients and have a negative impact on functioning and well-being comparable with other major chronic medical conditions. The San Francisco Depression Prevention Research project conducted a randomized, controlled, prevention trial to demonstrate the feasibility of implementing such research in a public sector setting serving low-income, predominantly minority individuals: 150 primary care patients free from depression or other major mental disorders were randomized to an experimental cognitive-behavioral intervention or to a control condition. The experimental intervention group reported a significantly greater reduction in depressive levels. Decline in depressive levels was significantly mediated by decline in the frequency of negative conditions. Group differences in the number of new episodes (incidence) of major depression did not reach significance during the 1-year trial. We conclude that depression prevention trials in public sector primary care settings are feasbile, and that depressive symptoms can be reduced even in low-income, minority populations. To conduct randomized prevention trials that can test effects on incidence with sufficient statistical power, subgroups at greater imminent risk have to be identified.  相似文献   
943.
This paper describes an apparatus that controls the output of a monochromator so that the energies in each waveband can be equated according to any desired function. A photocell monitors the light from the monochromator and provides a feedback to the power supply driving the lamp. A function generatoris mechanically linked to the monochromator’s wavelength drive and provides the function for correcting the output spectrum. Once set, the light output remains constant even if the bulb ages or is replaced. If desired, a sinusoidalripple of variable frequency and amplitude can be imposed on the mean intensity of the light.  相似文献   
944.
945.

On a method of constructing modal logics

Dzieła, którym przyporządkowano skrót, są cytowane w tekście.  相似文献   
946.
The effect of different attentional strategies on motor efficiency, measured by reaction-response time components, has historically been based on memory-drum construct theory, which implied limited attention and motor-response processing. The present study contrasts these principles by using a recording system and automatic analysis of reaction-response parameters. A within-subject design allowed detailed observation of the frequency of each preparatory set within each parameter and with control of the effects of practice. Analysis indicates (a) practice changes the effects of the attentional strategies on the components of reaction response but not the actual movement; (b) the motor-set strategy produces shorter movement times and, inversely, higher motor reaction times; and (c) the motor-sensory set integrated strategy produces improvements on each component of the reaction response. These findings suggest the memory-drum construct theory needs revision and should be based on other attentional models.  相似文献   
947.
In the present study, we investigated taste-taste, taste-vehicle, and simultaneous taste-vehicle-taste mixtures. Subjects made estimates of the sweetness and bitterness of 27 stimuli. Sucrose (292, 585, and 1170 mM), caffeine (13, 26, and 52 mM), and binary mixtures of low (292-13 mM), middle (585-26 mM), and high (1170-52 mM) levels of both components were dispersed in water, carboxymethylcellulose (CMC) 1% w/v, and gelatin 6% w/v. The sweetness and bitterness of the sucrose-vehicle-caffeine combinations were significantly weaker than the respective sucrose-vehicle and caffeine-vehicle combinations. The emerged mutual suppressive effects were asymmetrical and persisted when both tastants were presented in CMC and gelatin. Moreover, the increase in vehicle consistency and the simultaneous addition of another taste reduced the perceived intensity of a taste either presented alone or dissolved in water. For both sweetness and bitterness, the total taste suppression observed was always significant.  相似文献   
948.
Thirty-seven aphasic patients whose native language is Spanish were divided into four groups: (1) Broca's, (2) Wernicke's, (3) Conduction, and (4) Anomia. Phonological errors produced on repetition and object-naming tasks were analyzed in terms of type of transformation and degree of similarity between target and errors in terms of shared distinctive features. Segmental transformations were of the following types: (1) pure substitution, (2) pure addition, (3) deletion, (4) reduplicative addition (doublet creation)—anticipatory (right to left) or perseverative (left to right), (5) reduplicative substitution (doublet creation)—anticipatory or perseverative, and (6) mutual exchanges. Pure substitutions were the most prevalent, exchanges, the least. Some error types were found to differentiate significantly between aphasic populations. We suggest that different mechanisms may underlie the same error type for different aphasic populations.  相似文献   
949.
Puerto Rico has been a U.S. colony since 1898. For the past decades, it has been mired in public debt, social problems, and ineffective and corrupt governance. In 2017, the island was hit by hurricanes which devastated our country. After the event, the term “resilience” became ubiquitous. Labeling Puerto Ricans’ capacity to tolerate misfortune and suffering “resilient” gave people a false sense of hope and offered government a pretext to postpone or inequitably dispense aid. So-called “resilience” also allowed Puerto Ricans to avoid the impact of colonialism and coloniality on pre-existing conditions which hurricanes accentuated. In this context, community activism played a major role. Community organizations initially provided aid and generated chains of solidarity. They initiated “sovereign acts” which are mostly guided by principles and values espoused by community psychology. Thus, we have a duty to contribute to efforts which can promote liberating our island from colonialism and coloniality.  相似文献   
950.
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