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31.
Francisco J. Acosta Jose M. Serrano Jesus M. Barandica Francisco Lopez 《Journal of Insect Behavior》1992,5(3):337-346
The focal-animal technique assumes the continuous recording of the behavior of an individual during a certain time interval. The length of this interval (sampling unit) can be problematic when estimating the duration of behavioral acts. Two acts from the behavioral repertoire of the ant Leptothorax fuenteiwere focused on in this work at different ranges of temporal scales. Analyzing these acts we show the possibility of existence of a sampling artifact, in such a way that the estimates of the durations of the acts would be forced to depend upon the length of the sampling unit that is being used. 相似文献
32.
On nonparametric discrimination using density differences 总被引:2,自引:0,他引:2
33.
Residuals for relative risk regression 总被引:2,自引:0,他引:2
34.
Regression analysis based on stratified samples 总被引:1,自引:0,他引:1
35.
Estimation in linear models with censored data 总被引:1,自引:0,他引:1
36.
Longitudinal data analysis using generalized linear models 总被引:186,自引:0,他引:186
37.
本文报道了在AppleⅡ型微机上实现核酸数据处理的一系列工作程序。应用这些程序,可进行核酸数据的贮存、对指定的核酸数据结构的改造、限制性内切酶识别位点的检索、核酸序列至蛋白序列的翻译、相关核酸序列及蛋白序列的同源性比较、氨基酸密码使用频率的统计和基因的启动子结构的初步探索等方面的工作。 相似文献
38.
Jiro Hoshino 《Primates; journal of primatology》1985,26(3):248-273
A field study on the ecology of mandrills (Mandrillus sphinx) was carried out for 28 months in Cameroon. Fresh food remnants and large quantities of fresh feces were collected by following
the groups. Analyses of these products indicated that fruit (including seeds), monocotyledonous plant leaves and insects (especially
ants and termites), were frequently eaten. Mandrills mostly ate the plant and animal foods in the lower forest stratum and
on the ground. Fallen seeds and monocotyledonous plant leaves were eaten more frequently in the minor fruiting season than
in the major fruiting season presumably to compensate for the shortage of fresh fruit during the former. Daily travel distances
were shorter during the minor fruiting season than during the major fruiting season, because in the minor fruiting season
mandrills forage for small food items, such as the new leaves and piths of monocotyledons and fallen seeds which are sparsely
distributed on the ground, while in the major fruiting season they search for widely distributed food such as fruit. The daily
pattern of group movement and a food intake experiment suggest that mandrills move and feed continuously throughout the day.
Use of fallen seeds and monocotyledonous plant leaves appears to enable mandrills to maintain a terrestrial life in the tropical
rain forest. The feeding and ranging characteristics of mandrills are basically similar to those of other baboon species in
open land, though their environments differ extremely. 相似文献
39.
George M. White 《Cell biochemistry and biophysics》1987,11(1):25-33
Computers, the human mind, and social systems have common problems of inadequate memory and insufficient data manipulation
speed. In each of these domains, information compression techniques have evolved to reduce storage and processing needs. Among
the techniques for information compression, coding of information in procedures stands out as exceptionally powerful. Procedural
information coding also gives rise to behavior that may be defined as intelligent. It is found in the human mind, in machines
and in social systems. Its use in human thought is aided by language development which promotes regular review of abstract
procedures. A practical consequence of better understanding of procedural information coding is the possibility of training
people to exhibit greater mental capacity, a controversial possibility. This paper explores the impact of data processing
resource limitations, data compression and procedural thinking in men and machines. 相似文献
40.
Peter R. Minchin 《Plant Ecology》1987,69(1-3):89-107