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11.
Molecular sequence data, made available in the last 15 years or so, have led to the classification of living cells into three phylogenetic domains: Bacteria, Archaea, and Eucarya. All the organisms that have been tested belonging to either domain were capable of mounting a stress response with essentially the same characteristics, regardless of the stressor. The protagonists in the cell's stress response are the stress genes and their protein products. Some of the latter are molecular chaperones. Under physiological conditions, these chaperones aid other cellular proteins to fold properly and achieve a native -functional- configuration, and to translocate from the place of synthesis to the cell's locale in which they will operate. In a stressed cell, the stress proteins that are chaperones protect other molecules from denaturation and help those partially damaged to regain a functional configuration. Thus, cell death is avoided and recovery is enhanced. The study of stress genes and proteins has progressed considerably in organisms belonging to the domains Bacteria and Eucarya. Less is known about the archaeal stress genes. Here, research with an organism from the Archaea is discussed, focusing on the stress genes of the hsp70 (dnaK) locus. Future perspectives for basic and applied research within the health sciences and biotechnology industries are presented. 相似文献
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Pigeons were trained on a multiple schedule of reinforcement in which separate concurrent schedules occurred in each of two components. Key pecking was reinforced with milo. During one component, a variable-interval 40-s schedule was concurrent with a variable-interval 20-s schedule; during the other component, a variable-interval 40-s schedule was concurrent with a variable-interval 80-s schedule. During probe tests, the stimuli correlated with the two variable-interval 40-s schedules were presented simultaneously to assess preference, measured by the relative response rates to the two stimuli. In Experiment 1, the concurrently available variable-interval 20-s schedule operated normally; that is, reinforcer availability was not signaled. Following this baseline training, relative response rate during the probes favored the variable-interval 40-s alternative that had been paired with the lower valued schedule (i.e., with the variable-interval 80-s schedule). In Experiment 2, a signal for reinforcer availability was added to the high-value alternative (i.e., to the variable-interval 20-s schedule), thus reducing the rate of key pecking maintained by that schedule but leaving the reinforcement rate unchanged. Following that baseline training, relative response rates during probes favored the variable-interval 40-s alternative that had been paired with the higher valued schedule. The reversal in the pattern of preference implies that the pattern of changeover behavior established during training, and not reinforcement rate, determined the preference patterns obtained on the probe tests. 相似文献
13.
Patti Johnson M.S. John Schuster Ed.D. Jennifer K. Bell M.S. 《Journal of Behavioral Education》1996,6(4):437-458
This study compared the effectiveness and efficiency of simultaneous prompting with and without error correction during daily probe sessions in teaching science vocabulary words. The teacher presented the vocabulary word definitions as instructive feedback during training sessions. Five 16–17 year old students with disabilities participated in an adapted alternating treatments design that evaluated the simultaneous prompting strategy, error correction and instructive feedback. Instruction occurred in a group format using choral responding. The results indicate that (a) all students learned to read the vocabulary words, (b) simultaneous prompting with error correction was slightly more efficient for three of the five subjects in learning the targeted words, and four of the five students made fewer errors in this condition, (c) all students preferred simultaneous prompting with error correction over simultaneous prompting without error correction, (d) words mastered in both conditions generalized equally, (e) there were minimal differences between the two conditions in the collected maintenance data, and (e) students experienced only minimal improvement in their ability to define vocabulary words (instructive feedback). Discussion focuses on issues for further research and implications for instructional practice with simultaneous prompting, error correction and instructive feedback. 相似文献
14.
REM motivation induced by brief REM deprivation: the influence of cognition, gender, and personality. 总被引:1,自引:0,他引:1
D B Cohen M J McGarth L W Bell M J Hanlon N Simon 《Journal of personality and social psychology》1978,36(7):741-751
Prominence of the brain's right-hemisphere information processing and intensity of dream experience are two theoretically related constructs that have been proposed as important psychological aspects of REM sleep. Either view is consistent with the prediction that the effect of REM deprivation will depend in part on the nature of cognitive activity that is initiated at the onset of each REM period and that "substitutes" for the interrupted REM process. In the present study, the effect of REM deprivation was more striking for female subjects given a digits task than for female subjects given a fantasy-reporting task during awakening used to induce REM deprivation for the first 6 hours of the night. High neuroticism appeared to exaggerate the effect. No corresponding pattern was observed for the male subjects. These preliminary finding may be exaggerated by cognitive activity that is functionally incongruent with those processes. The results also raise interesting questions about individual differences. 相似文献
15.
Because carbon monoxide (CO) is an easily understood danger of cigarette smoking, new breath CO analyzers may be useful in cessation programs. Self-reported cigarette consumption and breath CO correlated .70 using a 90-sec. CO-determination method. Smokers averaging 17 daily cigarettes had average breath CO of 24 parts per million (ppm), falling to 7.71 ppm for smokers claiming at least 24-hr. abstinence. Corresponding carboxyhemoglobin (COHb) estimates were 4.34% (slightly above World Health Organization 4% safety limit) and 1.39%. Smoking clinics can use CO-monitoring devices for feedback or surveillance, although feedback would provide the most benefits for participants. 相似文献
16.
One hundred and sixty undergraduates (80 males, 80 females) participated in a field experiment designed to examine the influence of invasions of personal space and sex of requester upon subsequent helping. On the basis of previous research, it was predicted that helping would be markedly inhibited by invasions of personal space, and that the magnitude of these effects would be mediated by the sex of the individuals who perpetrated such intrusions. Surprisingly, however, results indicated that subsequent helping was actually facilitated by such invasions. A follow-up investigation replicated these results and suggested that they stemmed from a tendency on the part of subjects to perceive close physical approach by the requester as indicative of a high need for assistance. 相似文献
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Chance A. Bell Sarah A. Crabtree Eugene L. Hall Steven J. Sandage 《Counselling and Psychotherapy Research》2021,21(1):3-7
The COVID‐19 pandemic brings to light many areas the field of counselling and psychotherapy may need to address in future research. We outline several issues stemming from or exacerbated by the pandemic and offer suggestions for future research to address the mental health needs of those impacted. Our suggestions focus on five domains: (a) the health and well‐being of helping professionals, (b) the infodemic, (c) discrimination and minority stress, (d) spiritual and existential dynamics in mental health and (e) couple and family stress and resilience. We aim to provide a multi‐systemic perspective of mental health and well‐being in the time of COVID‐19, as well as encourage current and future studies to incorporate these suggestions to advance the health and well‐being of our communities through evidence‐based treatment approaches. 相似文献