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排序方式: 共有74条查询结果,搜索用时 421 毫秒
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Gerhard Grössing 《Foundations of Science》2001,6(4):255-272
It is shown that the evolution of physics canin several regards be described by elements of``regression', i.e., that within a certaintradition of ideas one begins with theconstruction of most ``plausible' statements(axioms) at hand, and then ``works onselfbackwards' with respect to developmental terms.As a consequence of this strategy, the furtherwork proceeds along such a ``regressive' path,the more one arrives at concepts andrelationships which are unexpected or evencounter-intuitive in terms of our everydayexperiences. However, a comparable phenomenology is wellknown from studies on states of consciousness.In particular, the evolutionary logic of theconstructions of major ``cognitive invariances'in physics, which is in part due to everincreasing rates of data processing, ismirrored in a logic of states of consciousnesswhich deviate from a ``normal' state of dailyroutine along increasing levels of centralnervous arousal. Examples are given from the evolution ofphysics, and future perspectives are brieflyoutlined on the basis thereof. 相似文献
33.
CALENDAR EFFECTS IN MONTHLY TIME SERIES MODELS 总被引:1,自引:1,他引:0
Gerhard THURY 《系统科学与系统工程学报(英文版)》2005,14(2):218-230
1. Introduction In the 1960s the attempts to describe an economy by large macroeconometric models were under heavy critique. These models with hundreds of macroeconomic variables and equations, could track the data very well over the historical period where the model parameters are estimated but often performed poorly when are used for out-of-sample forecasting. Part of the disillusionment with these efforts was the discovery that univariate time series models with low order autoregressive and… 相似文献
34.
Bipolar affective disorders linked to DNA markers on chromosome 11 总被引:13,自引:0,他引:13
J A Egeland D S Gerhard D L Pauls J N Sussex K K Kidd C R Allen A M Hostetter D E Housman 《Nature》1987,325(6107):783-787
An analysis of the segregation of restriction fragment length polymorphisms in an Old Order Amish pedigree has made it possible to localize a dominant gene conferring a strong predisposition to manic depressive disease to the tip of the short arm of chromosome 11. 相似文献
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Transgeneration memory of stress in plants 总被引:1,自引:0,他引:1
Owing to their sessile nature, plants are constantly exposed to a multitude of environmental stresses to which they react with a battery of responses. The result is plant tolerance to conditions such as excessive or inadequate light, water, salt and temperature, and resistance to pathogens. Not only is plant physiology known to change under abiotic or biotic stress, but changes in the genome have also been identified. However, it was not determined whether plants from successive generations of the original, stressed plants inherited the capacity for genomic change. Here we show that in Arabidopsis thaliana plants treated with short-wavelength radiation (ultraviolet-C) or flagellin (an elicitor of plant defences), somatic homologous recombination of a transgenic reporter is increased in the treated population and these increased levels of homologous recombination persist in the subsequent, untreated generations. The epigenetic trait of enhanced homologous recombination could be transmitted through both the maternal and the paternal crossing partner, and proved to be dominant. The increase of the hyper-recombination state in generations subsequent to the treated generation was independent of the presence of the transgenic allele (the recombination substrate under consideration) in the treated plant. We conclude that environmental factors lead to increased genomic flexibility even in successive, untreated generations, and may increase the potential for adaptation. 相似文献
38.
D S Gerhard N C Dracopoli S J Bale A N Houghton P Watkins C E Payne M H Greene D E Housman 《Nature》1987,325(6099):73-75
It was recently reported that different rare alleles at the Ha-ras-1 locus occurred at a significantly higher combined frequency in cancer patients than in an unaffected population. In particular, melanoma patients were reported to have a significantly higher frequency of such alleles. We have examined the frequency of rare Ha-ras-1 alleles in a large number of cases of sporadic melanoma. Our results indicate that the distribution of rare alleles in this population does not differ from that found in normal populations. Also, to test the hypothesis that a hereditary predisposition to melanoma could be inherited via an allele at the Ha-ras-1 locus, we examined the transmission of the segment of the short arm of chromosome 11 (11p) carrying the Ha-ras-1 locus in a number of families previously shown to exhibit a hereditary predisposition to melanoma and its precursor lesion, the dysplastic nevus syndrome (DNS). Our genetic linkage results thus obtained strongly exclude the association of a predisposition to melanoma or the precursor lesion with the inheritance of the Ha-ras-1 locus or the segment of chromosome 11 on which it is located. These results imply that hereditary predisposition to melanoma is associated with genes other than the Ha-ras-1 locus, contradicting the original suggestion of Krontiris et al., made on the basis of either an inadequate sample size or other misleading experimental factors. 相似文献
39.
North TE Goessling W Walkley CR Lengerke C Kopani KR Lord AM Weber GJ Bowman TV Jang IH Grosser T Fitzgerald GA Daley GQ Orkin SH Zon LI 《Nature》2007,447(7147):1007-1011
40.
Galagan JE Calvo SE Cuomo C Ma LJ Wortman JR Batzoglou S Lee SI Baştürkmen M Spevak CC Clutterbuck J Kapitonov V Jurka J Scazzocchio C Farman M Butler J Purcell S Harris S Braus GH Draht O Busch S D'Enfert C Bouchier C Goldman GH Bell-Pedersen D Griffiths-Jones S Doonan JH Yu J Vienken K Pain A Freitag M Selker EU Archer DB Peñalva MA Oakley BR Momany M Tanaka T Kumagai T Asai K Machida M Nierman WC Denning DW Caddick M Hynes M Paoletti M Fischer R Miller B Dyer P Sachs MS Osmani SA Birren BW 《Nature》2005,438(7071):1105-1115
The aspergilli comprise a diverse group of filamentous fungi spanning over 200 million years of evolution. Here we report the genome sequence of the model organism Aspergillus nidulans, and a comparative study with Aspergillus fumigatus, a serious human pathogen, and Aspergillus oryzae, used in the production of sake, miso and soy sauce. Our analysis of genome structure provided a quantitative evaluation of forces driving long-term eukaryotic genome evolution. It also led to an experimentally validated model of mating-type locus evolution, suggesting the potential for sexual reproduction in A. fumigatus and A. oryzae. Our analysis of sequence conservation revealed over 5,000 non-coding regions actively conserved across all three species. Within these regions, we identified potential functional elements including a previously uncharacterized TPP riboswitch and motifs suggesting regulation in filamentous fungi by Puf family genes. We further obtained comparative and experimental evidence indicating widespread translational regulation by upstream open reading frames. These results enhance our understanding of these widely studied fungi as well as provide new insight into eukaryotic genome evolution and gene regulation. 相似文献