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1.
In 3 studies, the authors explored age changes and individual differences in preschool children's sustained attention in several different contexts--watching a videotape, playing with toys, and performing reaction time tasks. Various indexes of attention increased from 30 months to 54 months, whereas inattention decreased. Changes tended to occur earlier for play and television viewing than for the reaction time task. Together, the results also provide evidence for individual differences in measures of attention and inattention through high internal consistency and stability over time within situations. Correlations across situations, however, were low to modest. These results suggest that children have stable tendencies to focus and sustain attention in particular contexts but that their attention varies with the demands of the task and their ability or interest in meeting those demands. 相似文献
2.
Research in the 1980s uncovered ubiquitous neuropeptide-receptor distribution in brain structures associated with emotional processing, and throughout many organ systems. This finding supported neuropeptides as biochemical substrates of emotion, and the neuropeptide-receptor network as a parasynaptic system crossing traditional brain-body boundaries. The medical relevance of these findings was affirmed by psychoneuroimmunology research: neuropeptides help to regulate immunocyte trafficking, there is bidirectional communication between nervous and immune system components, immunocytes produce neuropeptides, and nerve cells produce immune-associated cytokines. In the past decade, the concept of a unified psychosomatic network has been strengthened by animal and human research demonstrating relationships between behavior and neuropeptide-mediated regulation of immune functions. Research on emotional expression or disclosure in healthy human subjects as well as in cancer and HIV-positive patients has shown significant positive correlations with clinically relevant immune functions and/or positive health outcomes. Psychosocial interventions emphasizing emotional expression or active coping have evidenced survival benefits in breast cancer and melanoma. These findings suggest that emotional expression generates balance in the neuropeptide-receptor network and a functional healing system. Emotional expression is also a marker for psychospiritual vitalization, and further research should evaluate links between energy-based models of health and neuropeptide-receptor-based models under the rubric of an informational paradigm. 相似文献
3.
Islam Z Capatina D Ruff JP Das RK Trakhtenberg E Nojiri H Narumi Y Welp U Canfield PC 《The Review of scientific instruments》2012,83(3):035101
We present a pulsed-magnet system that enables x-ray single-crystal diffraction in addition to powder and spectroscopic studies with the magnetic field applied on or close to the scattering plane. The apparatus consists of a single large-bore solenoid, cooled by liquid nitrogen. A second independent closed-cycle cryostat is used for cooling samples near liquid helium temperatures. Pulsed magnetic fields close to ~30 T with a zero-to-peak-field rise time of ~2.9 ms are generated by discharging a 40 kJ capacitor bank into the magnet coil. The unique characteristic of this instrument is the preservation of maximum scattering angle (~23.6°) on the entrance and exit sides of the magnet bore by virtue of a novel double-funnel insert. This instrument will facilitate x-ray diffraction and spectroscopic studies that are impractical, if not impossible, to perform using split-pair and narrow-opening solenoid magnets. Furthermore, it offers a practical solution for preserving optical access in future higher-field pulsed magnets. 相似文献
4.
This paper examines the development of recreation on mountain bikes, since they were introduced in 1983. It considers some of the social conflicts that have reportedly arisen and then presents the results of a user survey undertaken in 1992. This provides a profile of mountain bike use and users. The aim of the study is to provide landscape managers, planners etc., with basic information about this latest form of countryside recreation so as to encourage more effective provision and management. 相似文献
5.
Klaus Ruff 《大分子材料与工程》1977,62(1):187-202
In polymer production inherent viscosity as a characteristic key of product quality should be as uniform as possible. For many polymers exists a close connection between inherent viscosity and melt viscosity. For the case of producing polymers in extruder reactors and putting them out through a nozzle, a linear relationship is developed between the inherent viscosity on the one side and the temperature and the pressure of the mass before the nozzle, the hourly throughput and the temperature of the nozzle on the other side. A simple physical model supports this relationship which is useful for control purposes and which obviates the installation of process viscosimeters. 相似文献
6.
The Gupo Bridge crosses the Nakdong River near the city of Busan, South Korea. During Typhoon Maemi in 2003, the old Gupo Bridge collapsed due to excessive pier scour. More recently, the highway construction on the left-bank floodplain required right-bank channel widening to restore the channel flood-carrying capacity. This 7?m deep floodplain excavation is expected to cause significant local scour around the 8–10?m wide and 3?m thick spread footings of Piers 11 and 12 of the Subway Bridge and Piers 15 and 16 of the Gupo Bridge. Three design options are examined for retrofitting floodplain bridge piers with massive spread footings. A solution with sheet piles and riprap was recommended in 2006 as the most appropriate design, but Plan III with a conical riprap structure around the footings was ultimately constructed in 2007 for economic reasons. Laboratory experiments also highlight the need to place gravel and synthetic filters under the designed riprap. 相似文献
7.
8.
Ruff Holly A.; Saltarelli Lisa M.; Capozzoli Mary; Dubiner Karen 《Canadian Metallurgical Quarterly》1992,28(5):851
If an activity during manipulative play is exploratory, it should, in contrast to other activity, be used differentially for objects that vary in novelty. In a study of 5-mo-olds, different definitions of exploratory mouthing were tested, and results suggest that mouthing followed immediately by a look fulfilled some criteria for an exploratory activity. In the next study of 5- to 11-mo-olds, mouthing with looks after and examining, a measure of visual–manipulative inspection, met the criteria for exploratory activity; other kinds of mouthing and visual–manipulatory activity did not. Exploratory mouthing decreased with age, and examining increased. The exploratory function of mouthing apparently was not due to concurrent manual activity providing haptic information. The conclusion is that some activities are exploratory and information-gathering and other activities are nonexploratory and serve other functions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
10.
J Brandt JR Campodonico JB Rich L Baker C Steele T Ruff A Baker C Lyketsos 《Canadian Metallurgical Quarterly》1998,13(8):509-515
AIM: To evaluate the influence of premorbid personality on adaptation to placement in a long-term care facility. SUBJECTS: Twenty-eight persons with probable Alzheimer disease (AD) residing in an academically affiliated nursing home for 6-9 months. METHODS: Premorbid personality was described retrospectively by two informants for each resident using the revised NEO Personality Inventory (NEO-PI-R). Standardized tests and rating scales were used on admission to the facility to assess cognition, mood state, physical dependency and general health. Nurses rated each AD resident's social behaviour, participation in activities and quality of sleep. RESULTS: Poorer adjustment was associated with more severe dementia but better physical health. None of the NEO-PI-R domain scores predicted adjustment. CONCLUSIONS: Contrary to popular belief, premorbid personality is relatively inconsequential for an AD patient's adaptation to a long-term care facility. 相似文献