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Dr. R. Goodwill F. D. Enfield 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1971,41(1):5-12
Summary Two-way selection for 21-day pupa weight was conducted in two highly inbred lines of Tribolium castaneum. The results, after 17 generations of selection, indicated that one of these lines (CSI-10) possessed a moderate amount of genetic variation for the trait selected (21-day pupa weight).When the selected populations were allowed to mate at random for 13 generations, the mean pupa weight regressed to values close to the means in the populations prior to selection. Reciprocal crosses between the high and low select lines revealed that 80% of the variation was associated with the sex chromosomes.The possibility that recurrent mutation was responsible for the genetic variation is discussed. It is concluded that natural selection favoring the heterozygous condition, rather than recurrent mutation, is responsible for the genetic variation. It is suggested that selection occurring between the sublines has reduced the rate at which the inbred line, CSI-10, is approaching complete homozygosity.The data have been taken from the doctoral thesis presented to the faculty of the University of Minnesota, St. Paul, by the senior author.Supported by NSFgrants G-1238, GB-5987 and NIH GM-16074. 相似文献
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Correlated response in male and female sterility to selection for pupa weight in Tribolium castaneum
D. D. Kress F. D. Enfield O. Braskerud 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1971,41(5):197-202
Summary The correlated responses in male and female sterility to 50 generations of individual selection for pupa weight in Tribolium were analyzed. Two replicate lines (S-lines) were selected for heavier pupa weight and stabilizing selection for pupa weight was practiced in two replicate control lines (C-lines). There was close agreement between replicates in both sets of lines for direct and correlated responses. The rate of inbreeding has been constant for all lines (approximately 0.5% per generation).Regression of generation means for pupa weight on generation of selection indicated a significant linear regression in the direct response for both lines. The linear increases of 46 and 55 g. per generation in the S-lines accounted for 98% of the variation among generations and the linear decreases of 5 and 10 g. per generation in the C-lines accounted for 70–90% of the variation in the generation means.Maximum likelihood estimators were used to calculate the frequency of male and female sterility for each generation and line. Average sterility in the base population ranged from about 4 to 12% for both sexes. Polynomial regressions of percent sterility on generation of selection showed that quadratic and higher order regressions were occasionally significant but accounted for a relatively small fraction of the total variation. In the two S-line replicates, linear regression coefficients of percent sterility on generation number were 0.16±.09 and 0.20±.07 for males and 0.72±.08 and 0.54±.08 for females, suggesting a larger correlated response in female than in male sterility. In the C-lines, linear regression coefficients were 0.02±.08 and –.12±.05 for males in the two replicates and –.05±.05 and –.05±.05 for females. Estimates of realized genetic correlations between pupa weight and sterility in the S-lines ranged from 0.04 to 0.14 for males and from 0.14 to 0.37 for females when the heritability of sterility was allowed to take on values from 0.05 to 0.25.Supported by NSF Grants G-1238 and GB-5987, NIH Grant GM-16074 and NIH Fellowship 1 FO2 GM4 5130-01. 相似文献
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Charles H.P. Zuckerman N.J. Enfield 《The journal of the Royal Anthropological Institute》2022,28(1):178-203
Kri people in central Laos traditionally engage in ‘heavy’ practices, including a stipulation that houses must be relocated and the flooring discarded upon a death in the family. Such ‘heavy’ practices are considered ‘real Kri’, and they are not adhered to by those who identify as Kri Phòòngq. This article examines the adoption of more enduring housing construction among the Kri, and the dynamics of ethnic identity implied by the dilemmas raised for individuals and families who must choose between (a) maintaining the heavy life of real Kri, (b) innovating new and less heavy solutions, or (c) changing identity entirely. 相似文献
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Roberto?H?Higa Roberto?C?Togawa Arnaldo?J?Montagner Juliana?CF?Palandrani Igor?KS?Okimoto Paula?R?Kuser Michel?EB?Yamagishi Adauto?L?Mancini Goran?NeshichEmail author 《BMC bioinformatics》2004,5(1):107
Background
The integration of many aspects of protein/DNA structure analysis is an important requirement for software products in general area of structural bioinformatics. In fact, there are too few software packages on the internet which can be described as successful in this respect. We might say that what is still missing is publicly available, web based software for interactive analysis of the sequence/structure/function of proteins and their complexes with DNA and ligands. Some of existing software packages do have certain level of integration and do offer analysis of several structure related parameters, however not to the extent generally demanded by a user. 相似文献7.
Bevan KS Chung Suresh Selvarasu Andrea Camattari Jimyoung Ryu Hyeokweon Lee Jungoh Ahn Hongweon Lee Dong-Yup Lee 《Microbial cell factories》2010,9(1):50
Background
Pichia pastoris has been recognized as an effective host for recombinant protein production. A number of studies have been reported for improving this expression system. However, its physiology and cellular metabolism still remained largely uncharacterized. Thus, it is highly desirable to establish a systems biotechnological framework, in which a comprehensive in silico model of P. pastoris can be employed together with high throughput experimental data analysis, for better understanding of the methylotrophic yeast's metabolism. 相似文献8.
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This commentary highlights the effectiveness of optoelectronic properties of polymer semiconductors based on recent results emerging from our laboratory, where these materials are explored as artificial receptors for interfacing with the visual systems. Organic semiconductors based polymer layers in contact with physiological media exhibit interesting photophysical features, which mimic certain natural photoreceptors, including those in the retina. The availability of such optoelectronic materials opens up a gateway to utilize these structures as neuronal interfaces for stimulating retinal ganglion cells. In a recently reported work entitled “A polymer optoelectronic interface provides visual cues to a blind retina,” we utilized a specific configuration of a polymer semiconductor device structure to elicit neuronal activity in a blind retina upon photoexcitation. The elicited neuronal signals were found to have several features that followed the optoelectronic response of the polymer film. More importantly, the polymer-induced retinal response resembled the natural response of the retina to photoexcitation. These observations open up a promising material alternative for artificial retina applications. 相似文献
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