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961.
Juslin Patrik N.; Liljestr?m Simon; V?stfj?ll Daniel; Barradas Gon?alo; Silva Ana 《Canadian Metallurgical Quarterly》2008,8(5):668
The Experience Sampling Method was used to explore emotions to music as they naturally occurred in everyday life, with a focus on the prevalence of different musical emotions and how such emotions are related to various factors in the listener, the music, and the situation. Thirty-two college students, 20 to 31 years old, carried a palmtop that emitted a sound signal seven times per day at random intervals for 2 weeks. When signaled, participants were required to complete a questionnaire on the palmtop. Results showed that music occurred in 37% of the episodes, and in 64% of the music episodes, the participants reported that the music affected how they felt. Comparisons showed that happiness-elation and nostalgia-longing were more frequent in episodes with musical emotions, whereas anger-irritation, boredom-indifference, and anxiety-fear were more frequent in episodes with nonmusical emotions. The prevalence of specific musical emotions correlated with personality measures and also varied depending on the situation (e.g., current activity, other people present), thus highlighting the need to use representative samples of situations to obtain valid estimates of prevalence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
962.
Ana Luisa Anaya Leticia Ramos Rocío Cruz José G. Hernández Verónica Nava 《Journal of chemical ecology》1987,13(11):2083-2101
Agroecosystems in Tlaxcala, Mexico, are surrounded by trees and water channels and have a great variety of cultivated and noncultivated plants. The main results of a study carried out on a traditional agroecosystem in Santa Inés, Tlaxcala are presented. Some ecological aspects of polycultures, plant covers (dry leaves ofAlnus firmifolia, Berula erecta, andJuncus sp.), and the allelopathic potential of crops and noncultivated plants (fresh and dry material) were analyzed. The main plants (trees, shrubs, and herbs) present in the agroecosystem were identified. The total number of weeds in plots where plant covers were added was reduced. The number of nodules ofRhizobium phaseoli and the production of bean and squash increased with plant covers. Corn, beans, and squash showed a clear allelopathic effect, as well asChenopodium murale, Tradescantia crassifolia, Melilotus indicus, andAmaranthus hybridus, among other weeds. The contribution of allelopathy in studies of traditional agroecosystems is of great importance for the management of species in space and time. Allelopathy can be the basis of biological control of pests and weeds and of the discovery of new useful substances. 相似文献
963.
The classical superfusion technique was modified by immersing the isolated assay tissues in mineral oil, making it possible to superfuse the preparations through the oil with a drip of Krebs solution at very low flow rates (0.1 - 0.2 ml/min). In this way the sensitivity of the preparation for the detection and quantitation of endogenous biologically active substances was extended to the picogram level. 相似文献
964.
da Costa Silva F. Barroso de Assis Fonseca S. Soares A.J.M. Giarola A.J. 《Antennas and Propagation, IEEE Transactions on》1991,39(9):1398-1404
The use of dyadic Green's functions and the moment method is explored for the solution of microstrip antenna problems on circular cylindrical substrates. The dyadic Green's functions of the electric type are obtained for a medium consisting of three cylindrical dielectric layers concentric with a perfectly conducting cylinder, and integral equations are developed for the evaluation of the electromagnetic fields. The effect of a dielectric overlay on the resonant frequency of a cylindrical-rectangular microstrip antenna is analyzed. The patch is directly fed by means of a microstripline printed along the cylinder axial direction. The results show that the effect of the dielectric overlay is substantial when its relative permittivity and thickness are increased, such that this effect has to be very carefully considered in the design of microstrip antennas 相似文献
965.
Ionic liquids have potential applications on separation technologies, as solvents for liquid extraction, gas absorbers and others. In this work, the ability of 1-ethyl-3-methyl imidazolium ethyl sulfate, [emim][EtSO4], to carry out the separation of tert-amyl ethyl ether and ethanol mixtures has been studied. New experimental LLE data for the ternary system are reported. Data correlation was done by means of the NRTL equation with satisfactory results (rmsd=0.429%). Extraction process was studied by means of solute distribution ratio and selectivity of the ionic liquid. Results were compared to other solvents from the literature. Solute distribution ratio for [emim][EtSO4] was acceptable (higher than 1) and selectivity was better than for other solvents. Then, extraction processes were also simulated using conventional software and obtained results are shown for comparison. Best TAEE recovery was obtained with [emim][EtSO4] and water. 相似文献
966.
Jessor Richard; Costa Frances; Jessor Lee; Donovan John E. 《Canadian Metallurgical Quarterly》1983,44(3):608
Longitudinal psychosocial data were used to predict the transition from virginity to nonvirginity among 430 7th–9th graders, all of whom were virgins at the initial testing in 1970. By the most recent follow-up in 1979, 93% reported having had sexual intercourse. Variation in time of onset of initial intercourse was categorized into 6 time periods and served as the main criterion variable in the study. Bivariate and multivariate analyses showed that antecedent measures of personality, the perceived environment, and behavior were predictive of variation in time of onset and, taken together, accounted for approximately 30% of the criterion variance. Results support the utility of the problem-behavior-theory framework and show onset of sexual intercourse to be a systematic aspect of psychosocial development in adolescence. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
967.
Early diagnosis, L-tiroxine therapy and adequate follow-up are determinant to remove the damages resulting from hormone deficiency in congenital hypothyroidism (CH). In order to achieve a better intellectual development, the authors suggest some guidelines for a correct follow-up on the basis of their personal experience on a population of 160 children with CH. These guidelines include monitored therapy, biochemical controls, instrumental investigations, clinical and auxological serial examinations. To better predict the mental outcome of these patients as adults, the authors propose a longer follow-up till adolescents, especially in the children with more severe hypothyroidism at diagnosis. 相似文献
968.
S Carozzi MG Nasini A Pietrucci M Costa R Mantero 《Canadian Metallurgical Quarterly》1994,40(3):M683-M685
To evaluate the 1-year effects of PFD performed with low Ca2+ dialysate (1 mmol/l) on calcium metabolism and on bone disease, the authors studied in eight patients who were previously treated with PFD performed with standard Ca2+ dialysate (1.75 mmol/l). On samples from these subjects, the following were evaluated: 1) serum Ca2+ and PO4 levels, 2) serum PTH levels, 3) serum Al levels, and 4) bone morphology. All the patients were hypercalcemic, four with high serum PTH levels (high turnover bone disease, group 1) and four with low serum PTH levels (low turnover bone disease, group 2). In both groups, a decrease in serum Ca2+ and an increase in serum PTH was observed within the third month. In group 2, PTH levels reached the normal range. Because serum Ca2+ levels decreased to normal in both groups, it was possible to administer oral CaCO3 (10.5 +/- 2 g/day) to control serum PO4 and to stop Al gels. This did not induce any increase in serum Ca2+, whereas serum Al fell significantly. In group 1, to prevent a further rise in PTH, patients were treated with intravenous calcitriol (5 +/- 2 micrograms/week). This induced a reduction in the serum PTH without increasing serum Ca2+ or PO4. Within 12 months, an improvement in bone morphology was seen in both groups. It is concluded that the use of low Ca2+ dialysate corrects hypercalcemia in patients with PFD treated with high oral doses of CaCO3, and improves low turnover bone disease. The combination of low Ca2+ dialysate and intravenous calcitriol also improves high turnover bone disease. 相似文献
969.
970.
Results of the combination of a ray-tracing computer model with measured refractive-index vertical profiles to study the relationship between copolar attenuation and crosspolar discrimination due to multipath effects on LOS frequency-reuse microwave links are reported. The results are in good agreement with those obtained by direct measurements. 相似文献