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331.
L. J. Young 《Biometrical journal. Biometrische Zeitschrift》1994,36(5):627-637
An algorithm is developed for determining exact values of the Operating Characteristic and Average Sample Number functions for Wald's Sequential Probability Ratio Test (SPRT) when observations are drawn from a discrete, Koopman-Darmois density with positive probability on the nonnegative integers. The sample size distribution and percentiles of sample size are also considered. An example is given for the negative binomial distribution. 相似文献
332.
B. Beck C. Villaume J.A. Chayvialle P. Gariot M. Ulmer A. Desalme G. Debry 《Peptides》1984,5(2):403-406
Blood glucose, gastric inhibitory polypeptide (GIP), vasoactive intestinal polypeptide (VIP) and gastrin secretions were measured over a three-hour period following the ingestion by normal subjects of a mixed meal with two different caloric levels (1055 Kcal and 1192 Kcal). No VIP secretion was observed after either meal. Gastrin release was not modified by the increase of caloric intake (mainly carbohydrates and lipids), whereas GIP secretion was significantly more important after the meal with the highest caloric value (peak at 30 mn: vs. and integrated response vs. ). This difference could not be attributed to glucose since the blood glucose levels were not significantly different. It is more probably related to the total amount of ingested food. This suggests the existence of rapid mechanisms of adaptation to the incoming load of the GIP-producing cells. 相似文献
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Veikko Salonen 《植被学杂志》1992,3(1):109-112
Abstract. This paper describes the effect of artificial plant cover on plant colonization of a bare peat surface, resulting from peat harvesting. Plant species colonization was compared on plots supplied with plastic models simulating Vaccinium vitis-idaea plants and plots without this artificial cover. After two growing seasons, species composition and total biomass of the established plant cover were similar in the two plot types. However, the number of established seedlings in the plots with artificial cover was significantly higher than that in the plots without cover. Out of 13 species observed four differed significantly in their performance on the two plot types. Betula spec. had both higher seedling numbers and higher biomass on the test plots; Deschampsia cespitosa had a higher biomass, whereas the seedlings were too numerous to be counted; Salix phylicifolia had higher seedling numbers. On the contrary, the number of seedlings of Epilobium angustifoliwn was lower on plots with artificial cover. It is suggested that colonization by Betula, D. cespitosa and S. phylicifolia was facilitated mainly by the improved microclimatic and soil moisture conditions under the artificial plant cover. On the other hand, germination of E. angustifolium may be negatively influenced by the increased shade on the test plots. 相似文献
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Plots and tests for symmetry 总被引:1,自引:0,他引:1
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