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991.
Two experiments examined habituation and dishabituation of behavioral responding to repeated presentations of a tactile stimulus (brush stroke) in 48 newborns during the 1st epoch of active-quiet sleep following a feeding. Exp I demonstrated habituation to a repeatedly presented brush stroke to the ear but failed to demonstrate dishabituation (i.e., response recovery) to the original brush stroke following an intense auditory stimulus (86 dB rattle sound). A post hoc control group showed that the intense auditory stimulus had suppressed subsequent responding to the tactile stimulus. Exp II replicated the habituation phase of Exp I and demonstrated response recovery to stimulation at a novel tactile site and to an auditory probe. Results indicate that the habituation paradigm used in infancy research could be successfully extended to the tactile modality. It is also suggested that prior auditory stimulation, but not prior tactile stimulation, might direct attention away from a subsequently presented tactile stimulus. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Walker Elaine; Bettes Barbara A.; Kain Edward; Harvey Philip 《Canadian Metallurgical Quarterly》1985,94(1):42
Examined the relationship of gender and marital status with ratings of symptoms in 882 psychiatric patients (521 males and 361 females) diagnosed as schizophrenic on the DSM-II. Analysis of total symptom scores revealed an interactive effect of gender and marital status; married women (mean age 37.02 yrs) had the highest total symptom scores, whereas married men (mean age 34.88 yrs) had the lowest. Factor analysis of the symptom ratings yielded 9 symptom factors: Ideational Symptoms, Anhedonia, Cognitive Disorientation, Suicidal Tendencies, Vegetative Symptoms, Hostility, Anxiety, Narcotic Abuse, and Alcohol Abuse. Factor scores were then computed to investigate possible gender and marital status differences in symptom pattern. Different profiles of symptoms as a function of gender were found. Females scored higher on the factors defined by affective symptoms, namely, Anhedonia, Suicidal Tendencies, and Vegetative Symptoms. They also scored higher on Cognitive Disorientation. The only factor on which males scored higher than females was Alcohol Abuse. Results are discussed in light of selection and protection theories of the relationship between marital status and mental health. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Ornstein Peter A.; Medlin Richard G.; Stone Barbara P.; Naus Mary J. 《Canadian Metallurgical Quarterly》1985,21(4):633
Two experiments with 96 2nd graders and 24 6th graders explored the operation of retrieval processes in Ss' active rehearsal strategies. Both experiments used free-recall tasks, in which Ss were given instructions in active rehearsal as well as supports that might facilitate the retrieval operation and thus enhance both rehearsal and recall performance. In Exp I, 2nd and 6th graders were given visual or auditory access to an 18-item stimulus-word list. Results show that, by providing 2nd graders with an opportunity to view previously presented words, rehearsal activity and recall increased substantially, whereas the performance of the 6th graders was not affected. In Exp II, presentation time and visual access to a similar 18-word list were manipulated for 2nd graders. Results show that the provision of extra time for an item enabled Ss to execute a more active rehearsal strategy. Extra time had only minimal effects on recall, except when it was combined with visual access to the items. Findings suggest that retrieval per se is not necessary for the beneficial effects of active rehearsal, if other procedures can be followed to permit the juxtaposition of several items in rehearsal. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
Treatments which successfully controlled bruchids in on-farm experiments were evaluated to determine effects on seed quality and cooking time. Relative cooling time was determined by cooking beans to the half-cooked point in a modified Mattson cooker. Germination was determined by trials planted in sand, and seedling vigor was estimated by dry weight of 8-day old seedlings. Cooking time, germination, and seedling vigor were not significantly changed by storage treatment with vegetable oil, threshing residues, kitchen ash, Malathion and black pepper. Analysis of bruchid damage on seed quality showed a decline in germination and seedling vigor related to the number of emergence holes. 相似文献
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997.
Alan E. Johnson WŁOdztmierz Jarzęba Gilbert C. Walker Paul F. Barbara 《Israel journal of chemistry》1993,33(2):199-206
The class of compounds containing a carbonyl group substituted at the 9 position of anthracene have been studied as new model systems for torsional isomerization in solution. Franck-Condon excitation yields an excited-state distribution near the barrier for isomerization in S1. Using time-resolved fluorescence spectroscopy, we have determined that the relaxation from the barrier region is subpicosecond for three different compounds in all solvents studied. In fact, the relaxation seems to be almost independent of solvent at room temperature, indicating that most of the local friction felt by the twisting carbonyl is internal friction rather than solvent friction. Apparently the small carbonyl is effectively shielded from the solvent by the anthracene ring so the solvent friction is not strong. In contrast to the weak solvent coupling, previously reported gas-phase spectra indicate that the torsion may be strongly coupled to the other vibrational modes of the molecule. Energy flow out of the torsion into these other vibrational modes appears to occur on the subpicosecond time scale. 相似文献
998.
We examined the existence of temporal dimensions of organization culture (e.g., norms of time in organizations) and developed an instrument to measure those dimensions to facilitate cross-organizational and intraorganizational comparisons. A questionnaire designed to measure 15 hypothesized temporal dimensions was completed by 529 respondents from 51 work groups in 23 organizations. The sample was selected to meet certain criteria concerning organization type, organization size, and work group type. A principal components analysis extracted 13 usable scales: Time Boundaries Between Work and Nonwork, Sequencing of Tasks, Punctuality, Allocation, Awareness, Synchronization and Coordination, Variety Versus Routine, Intraorganizational Time Boundaries, Future Orientation, Schedules and Deadlines, Work Pace, Autonomy of Time Use, and Quality Versus Speed. Two hypothesized scales (Buffer in Planning and Buffer in Workday) did not emerge. Applications of the Time Dimensions Scales are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
The bacterial endospores of C. sporogenes ATCC 3584 are quite small (approximately 0.7–1.0 μm in length) and are difficult to examine during the attachment and germination process by conventional light microscopy methods. Although transmission electron microscopy provides high magnification and resolution, it has not been possible to date to visualize the attachment process and surface changes of intact clostridial endospores. With the advent of higher resolution conventional scanning electron microscopes (SEM), it is now possible to study these small spores attached to their nutrient substrate in their intact state and readily obtain detailed morphologic information about the attachment, germination, and outgrowth process. Spores were examined in their dormant, dehydrated state and allowed to germinate. Samples were prepared for light, transmission, and SEM under anaerobic conditions for morphologic and histochemical examination. SEM revealed that the spores developed a distinct polarity at the beginning of the germination process and that the exosporial membrane at this time produced projections that attached the spore to a substrate. These projections were altered by calcium chelation with EDTA and the presence of barium. Following colchicine and cytochalasin B treatment, the exosporial membrane projections were morphologically altered and the germination sequence was modified. Histochemical examination of the spores suggested that calcium was predominantly located in the protoplast and spore coat. 相似文献
1000.
Jane E. Lancaster Barbara J. McCallion Martin L. Shaw 《Journal of the science of food and agriculture》1984,35(4):415-420
Flavour precursors, the S-alk(en)yl-L -cysteine sulphoxides, change considerably in both concentration and total amount during the growth of onions. For the brown onion cv. Pukekohe Long Keeper (PLK) and for the white onion cv. Dehyso, (±)-S-1-propyl-L -cysteine sulphoxide (±PCSO) is the predominant flavour precursor, with (±)-trans-S-1-propenyl-L -cysteine sulphoxide (±PECSO) and (±)-S-1-methyl-L -cysteine sulphoxide (±MCSO) in a minor role. For PLK the greatest concentration of all three precursors is just prior to bulbing (3.6±1.1 mg g?1 fresh weight); for Dehyso the greatest concentration is at bulbing (4.6±0.6 mg g?1 fresh weight); Both varieties show a mid-season reduction in flavour precursor concentration (of about 45%), followed by a small but significant increase in ±PCSO concentration during the end of season leaf die-down. The total amount of the three flavour precursors per bulb in both varieties shows a maximum in late January (360±107 mg for PLK, 602±144 mg for Dehyso). In the subsequent months there is a dramatic reduction in the total amount of ±PECSO and ±MCSO, and a slight reduction in ±PCSO. Both varieties show an increase in the amount of ±PCSO at leaf die-down. The relative proportions of these flavour precursors change with bulb age and cultivar. These results suggest that white onions used for drying and processing could be harvested from bulbing onwards. Furthermore, when onion cultivars and onion plant selections are assessed for flavour, care needs to be given to the stage of maturity of the onion. 相似文献