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The ability to reengage with new attainable goals after major setbacks is a core self-regulatory trait linked to health and well-being. Yet little is known about the extent to which such goal reengagement capacities may shift over time in response to changing contextual circumstances. Using a nationally-representative sample of U.S. adults aged 18–80 (n = 293), the present 1-year study examined whether changes in opportunity to influence life circumstances (perceived control) were coupled with dynamic shifts in goal reengagement capacity for individuals who differed in their levels of control at pandemic onset. Results from multilevel models showed that within-person increases in perceived control during the pandemic predicted corresponding within-person increases in goal reengagement capacity. Moderation models showed that the positive within-person association between perceived control and goal reengagement was pronounced for individuals with lower levels of control at pandemic onset who may be particularly sensitive to periods of opportunity to pursue new attainable goals. Findings inform theories of personality and self-regulation in pointing to contextual circumstances under which goal reengagement capacity exhibits dynamic shifts in populations who differ in their perceived opportunities for control.  相似文献   
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In light of information uncovered about human radiation experiments conducted during the Cold War, an important charge for the Advisory Committee on Human Radiation Experiments was to assess the current state of protections for human research subjects. This assessment was designed to enhance the Committee's ability to make informed recommendations for the improvement of future policies and practices for the protection of research subjects. The Committee's examination of current protections revealed great improvement over those from the past, yet some problems remain. Although the data collected by the Committee highlight specific areas in need of attention, the Committee's work should be viewed in part as the beginning of a series of ongoing assessments of the adequacy and effectiveness of the protections afforded to human subjects.  相似文献   
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The present studies investigated the relationship between prepulse effects on the modification of the brainstem startle reflex and magnitude estimates of startle-eliciting stimuli. In Experiment 1, startle eyeblink responses were elicited in 24 students, half of whom were instructed to estimate the loudness of the startle stimulus (actual intensities of 80, 90, and 100 dB) and half of whom were instructed to estimate the magnitude of their eyeblink. When weak acoustic prepulses preceded the startle-eliciting stimulus, eyeblink amplitude was inhibited, and estimates of response magnitude decreased, but estimates of startle stimulus magnitude decreased only when 100-dB startle stimuli were presented. In Experiment 2, the same startle stimuli were preceded on some trials by a vibrotactile prepulse to the hand. In conditions in which startle amplitude was inhibited, startle stimulus magnitude estimates were not affected. This suggests that the effect of acoustic prepulses on 100-dB startle stimuli in Experiment 1 may have been due to loudness assimilation, an effect independent of the prepulse inhibition of startle responding.  相似文献   
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Twenty-nine infants exposed in utero to methadone and 37 comparison infants were examined on the Neonatal Behavioral Assessment Scale at early and late neonatal ages. All infants were full-term at birth, over 2500 g, and not yet circumcised at the early assessment. None of the methadone-exposed infants were breast-fed or were being treated pharmacologically for withdrawal. During the first week of life, methadone-exposed neonates differed from comparison ones in motoric behavior. Relative to comparison-group infants, they were jerkier and more tremulous, tense, active, and better able to put hand in mouth. By the end of the first month these differences diminished, although there was still a tendency for the methadone-exposed infants to have elevated body tonus. Neither perinatal complications, birth weight, nor sex of infant could explain the early neonatal differences between the methadone and comparison groups. Past the early stage of acute withdrawal, neonates exposed prenatally to methadone behave not unlike their nonexposed peers.  相似文献   
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Characteristic patterns of conditioned key-pressing were maintained in the chimpanzee under a multiple 30-response fixed-ratio, 10-minute fixed-interval schedule of food presentation. Adjunctive drinking occurred with regularity during the fixed-interval schedule and, with less frequency, during 1-minute timeout periods that followed each food presentation; drinking seldom occurred during the fixed-ratio schedule. Cocaine increased key pressing under the fixed-interval schedule at doses between .1 and 3.0 mg/kg, but adjunctive drinking and key pressing under the fixed-ratio schedule did not increase at any dose. Conditioned and adjunctive behaviors were disrupted and suppressed for different durations at 10,0 mg/kg, a dose which induced convulsive seizures within 10 minutes after intramuscular injection. A time-course analysis showed the magnitude and duration of the effects of cocaine on key pressing under the fixed-interval schedule and on adjunctive drinking to be dose-related. Moreover, a given dose of cocaine had diverse effects, depending on the behavior and the time since drug administration.  相似文献   
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The behavioral effects of d-amphetamine sulfate were studied in adult male stumptail macaques living within a large heterogeneous group in an outdoor enclosure. Among five subjects that received a range of doses (.01 to .3 mg/kg), d-amphetamine increased self-aggressive behavior and abnormal posturing in subjects that exhibited these types of behavior prior to drug administration, but it had no effect in subjects not exhibiting those activities in the absence of the drug. For the former subjects, the dose-effect curves for self-aggression were of an inverted U-shape analogous to the effect of d-amphetamine on schedule-controlled behavior. Over the range of doses studied, the curve for abnormal posturing was monotonic. The data indicate that d-amphetamine can have effects on untrained behavior in individual animals in a quasinatural environment that are qualitatively and quantitatively similar to the behavioral effects observed in other laboratory environments, and that d-amphetamine does not evoke or increase a behavioral response in individual subjects that do not exhibit the response in the absence of the drug.  相似文献   
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