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931.
932.
N. M. Builova E. M. Epshtein V. G. Shamaev 《Scientific and Technical Information Processing》2008,35(1):28-29
The necessity for publishing a separate abstract journal on spintronics, which is a new, rapidly developing branch of physics, is substantiated. The interest in spintronics, which is the study of fundamental processes involving the simultaneous transport of both electron charge and electron spins in solids, as well as the interaction of electrons with a magnetic grating, is determined not only by its fascinating prospects but also the results that have already achieved. The spin and charge “degrees of freedom” open possibilities for the creation of semiconducting devices with parameters that are much superior to the existing ones and also the construction of devices that do not have analogues at present. First of all, this will permit problems of information transmission and processing to be solved in a new way. A detailed rubrication on spintronics is given in order to discuss the possibility of publishing a separate edition of an abstract journal devoted to spintronics. 相似文献
933.
U. Casellato F. Fenzi P. Guerriero S. Sitran P. A. Vigato U. Russo M. Galgani M. Mendera A. Manasse 《Journal of Cultural Heritage》2003,4(4):337-353
A significant number of archaeological finds of the 13th–16th century from the Tuscan sites of Germagnana and Gambassi in Valdelsa—FI, was studied by different physico-chemical investigations (SEM–EDS, ICP, Mössbauer spectroscopy, XRD, XRF, TG-DTA) in order to contribute to clarify the production methodology and the pre-industrial glass manufacture technology. The studied samples are mainly non-vitreous finds as production waste, refractory materials, crucibles and raw materials; also vitreous finds as frits, skims, glasses (glass masses, glass working waste and finished products) have been taken into consideration. The obtained petrographic and physico-chemical data strongly suggest that both Gambassi and Germagnana glass manufactures were strictly connected with the sources of vitrifiable materials, situated in Tuscan sand quarries. In particular a comparison between sands from the neighbouring quarries and appropriate finds of the two archaeological sites evidences that the employed vitrifiable materials possibly belong to La Casina La Cava resort. The archaeological classification, based on macroscopic observation and stratigraphic position, was compared and verified with the scientific classification of the examined finds of Germagnana and Gambassi sites based on their composition, morphology and physico-chemical properties. 相似文献
934.
935.
936.
The Infant Characteristics Questionnaire (ICQ) was developed as a short, factor-analytic screening device for difficultness. Responses of 322 mothers of 4-6-month-old infants suggested that they regard the fussy, hard-to-soothe, labile infant as difficult. Mother report on the ICQ, particularly on the main fussy-difficult factor was found to have adequate reliability over time and convergence with the Carey Survey of Temperamental Characteristics, with father report on the ICQ, and, to a lower degree, with home data collected by independent observers. It was also found that mother characteristics may affect perceptions of infant difficultness: multiparous, extraverted mothers tended to rate their infants as easy. 相似文献
937.
Leslie D. Leve David C. R. Kerr Daniel Shaw Xiaojia Ge Jenae M. Neiderhiser Laura V. Scaramella John B. Reid Rand Conger David Reiss 《Child development》2010,81(1):340-356
To further the understanding of the effects of early experiences, 9-month-old infants were observed during a frustration task. The analytical sample was composed of 348 linked triads of participants (adoptive parents, adopted child, and birth parent[s]) from a prospective adoption study. It was hypothesized that genetic risk for externalizing problems and affect dysregulation in the adoptive parents would independently and interactively predict a known precursor to externalizing problems: heightened infant attention to frustrating events. Results supported the moderation hypotheses involving adoptive mother affect dysregulation: Infants at genetic risk showed heightened attention to frustrating events only when the adoptive mother had higher levels of anxious and depressive symptoms. The Genotype × Environment interaction pattern held when substance use during pregnancy was considered. 相似文献
938.
Professor Dr. Matti Koskenniemi Eivi Lihtonen M. Ed. 《Scandinavian Journal of Educational Research》2013,57(1):157-168
Gustafsson, J.‐E. Differential Effects of Imagery Instructions on Pupils with Different Abilities. Scandinavian Journal of Educational Research, 21, 157‐179. A study investigating interactions between imagery instructions and aptitude variables is presented. A group of seven fifth‐grade classes was given imagery instructions in the reading of a short text, while another group read the text in a regular way. Three different outcomes covering different types of learning were registered. Tests of verbal ability and spatial (or imagery) ability were used as aptitude variables. The data analysis indicated that there were differences for the girls between the treatment groups among the aptitude variables; the results for the girls thus had to be excluded. A positive effect of imagery instructions was found for boys high in verbal and imagery ability with respect to the acquisition of simple terms. For other outcomes and groups of subjects either no effect or a negative effect was found. 相似文献
939.
A completely general three-dimensional dynamic model is presented for the motion of basketball shots that may contact the rim, the backboard, the bridge between the rim and board, and possibly the board and the bridge simultaneously. Non-linear ordinary differential equations with six degrees of freedom describe the ball angular velocity and ball centre position. The model includes radial ball compliance and damping and contains five sub-models: purely gravitational flight, and ball-rim, ball-bridge, ball-board, and ball-bridge-board contact. Each contact sub-model has both slipping and non-slipping motions. Switching between the sub-models depends on the reaction force at, and velocity of, the contact point. Although the model can be used to study shots from any point on the court, we here use it to study the sets of free throw release angle, velocity, angular velocity, and lateral deviation angle that result in success (capture), as well as underhand free throws and those using an under-inflated ball. Free throw shots with larger backspin, lower inflation pressures, and underhand release conditions are shown to result in larger capture percentages. 相似文献
940.
Lawrence GR Gottwald VM Hardy J Khan MA 《Research quarterly for exercise and sport》2011,82(3):431-441
In the current experiment, we examined optimal focus for novices during a movement sequence in which performance was measured on accurate movement form/technique. A novel gymnastics routine was practiced under either an internal skill-relevant, internal skill-irrelevant, external, or no attention focus. Retention and transfer tests were then completed. During acquisition, adopting an internal irrelevant focus significantly improved performance, whereas an external focus degraded performance. There were no significant group differences in the retention and transfer tests. This suggests that learning of movement form/technique did not benefit from a specific focus of attention. The results are interpreted via an attentional capacity viewpoint and the notion that form tasks do not always contain obvious movement effects central to common coding and the constrained action hypothesis. 相似文献