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91.
Nineteenth-century spiritism was a blend of religious elements, the philosophy of mind, science and popular science and contacts with extraterrestrials were a commonplace phenomenon during spiritistic séances. Using the example of Carl du Prel (1839–1899) I show how his comprehensive mystic philosophy originated in a theory of extraterrestrial life. Carl du Prel used a Darwinian and monistic framework, theories of the unconscious and a Neo-Kantian epistemology to formulate a philosophy of astronomy and extraterrestrial life. He claimed that the mechanism of Darwinian selection is responsible for the distribution of stars and the orbits of the planets. In his speculations on the nature of extraterrestrial life he used the concept of organ projection to argue that technical solutions on earth will be realized organically on other planets and claimed that superior extraterrestrials have quantitatively and qualitatively different senses and thus different forms of intuition. A comparison with Camille Flammarion, spiritist and populariser of astronomy, demonstrates the contextual complexities of spiritism. In contrast to du Prel’s sober Neo-Kantian philosophical speculations, Flammarion was a late proponent of a French esoteric tradition that was rooted in romantic socialism, painted grand cosmological vistas and emphasized reincarnation. I put forward the hypothesis that current discourses on extraterrestrial life are affected by the spiritist tradition mainly through the ‘Golden Age’ science fiction literature of the 1940s and 50s and its successors. However, neither Carl du Prel nor Camille Flammarion contributed significantly to this tradition, which is mainly shaped by the psychical research of J. B. Rhine. 相似文献
92.
Saether BE Lande R Engen S Weimerskirch H Lillegård M Altwegg R Becker PH Bregnballe T Brommer JE McCleery RH Merilä J Nyholm E Rendell W Robertson RR Tryjanowski P Visser ME 《Nature》2005,436(7047):99-102
Theoretical studies have shown that variation in density regulation strongly influences population dynamics, yet our understanding of factors influencing the strength of density dependence in natural populations still is limited. Consequently, few general hypotheses have been advanced to explain the large differences between species in the magnitude of population fluctuations. One reason for this is that the detection of density regulation in population time series is complicated by time lags induced by the life history of species that make it difficult to separate the relative contributions of intrinsic and extrinsic factors to the population dynamics. Here we use population time series for 23 bird species to estimate parameters of a stochastic density-dependent age-structured model. We show that both the strength of total density dependence in the life history and the magnitude of environmental stochasticity, including transient fluctuations in age structure, increase with generation time. These results indicate that the relationships between demographic and life-history traits in birds translate into distinct population dynamical patterns that are apparent only on a scale of generations. 相似文献
93.
Mapping determinants of human gene expression by regional and genome-wide association 总被引:1,自引:0,他引:1
To study the genetic basis of natural variation in gene expression, we previously carried out genome-wide linkage analysis and mapped the determinants of approximately 1,000 expression phenotypes. In the present study, we carried out association analysis with dense sets of single-nucleotide polymorphism (SNP) markers from the International HapMap Project. For 374 phenotypes, the association study was performed with markers only from regions with strong linkage evidence; these regions all mapped close to the expressed gene. For a subset of 27 phenotypes, analysis of genome-wide association was performed with >770,000 markers. The association analysis with markers under the linkage peaks confirmed the linkage results and narrowed the candidate regulatory regions for many phenotypes with strong linkage evidence. The genome-wide association analysis yielded highly significant results that point to the same locations as the genome scans for about 50% of the phenotypes. For one candidate determinant, we carried out functional analyses and confirmed the variation in cis-acting regulatory activity. Our findings suggest that association studies with dense SNP maps will identify susceptibility loci or other determinants for some complex traits or diseases. 相似文献
94.
Mapping the Hawaiian plume conduit with converted seismic waves 总被引:4,自引:0,他引:4
The volcanic edifice of the Hawaiian islands and seamounts, as well as the surrounding area of shallow sea floor known as the Hawaiian swell, are believed to result from the passage of the oceanic lithosphere over a mantle hotspot. Although geochemical and gravity observations indicate the existence of a mantle thermal plume beneath Hawaii, no direct seismic evidence for such a plume in the upper mantle has yet been found. Here we present an analysis of compressional-to-shear (P-to-S) converted seismic phases, recorded on seismograph stations on the Hawaiian islands, that indicate a zone of very low shear-wave velocity (< 4 km s(-1)) starting at 130-140 km depth beneath the central part of the island of Hawaii and extending deeper into the upper mantle. We also find that the upper-mantle transition zone (410-660 km depth) appears to be thinned by up to 40-50 km to the south-southwest of the island of Hawaii. We interpret these observations as localized effects of the Hawaiian plume conduit in the asthenosphere and mantle transition zone with excess temperature of approximately 300 degrees C. Large variations in the transition-zone thickness suggest a lower-mantle origin of the Hawaiian plume similar to the Iceland plume, but our results indicate a 100 degrees C higher temperature for the Hawaiian plume. 相似文献
95.
Kinetics of BRCA1 regulation in response to UVC radiation 总被引:1,自引:0,他引:1
To investigate changes in BRCA1 following DNA damage, we exposed MCF-7 cells to increasing doses of ultraviolet C. We observed
an increase in BRCA1 protein levels above 78 J/m2. This increase was observed as early as 5 min after irradiation. BRCA1 levels were then observed to decrease after 2 h, consistent
with the previously published data. By pretreating with cycloheximide prior to irradiation, we observed a decrease in the
protein half-life, from 3.5 h to 53 min, suggesting that a decrease in protein half-life may cause the lower levels of BRCA1
after irradiation. We also observed an increase in BRCA1 mRNA within 15 min of irradiation, followed by a decrease after 4
h. These data suggest that newly translated protein may contribute to increases in BRCA1 protein levels. The very rapid changes
in BRCA1 support its role as a sensor of DNA damage, as opposed to being a repair gene.
Received 6 April 2000; received after revision 23 May 2000; accepted 23 May 2000 相似文献
96.
In vivo degradation of mutant lac repressor 总被引:19,自引:0,他引:19
97.
W. Schmahl E. Senft L. Weber H. Kriegel 《Cellular and molecular life sciences : CMLS》1979,35(4):541-543
Summary Fractionated X-irradiation of mouse fetuses on gestation days 11–13 resulted in a significantly increased postnatal mortality of female litters. This occurred only at 3×110 rad, which was the threshold for the formation of typical neuroepithelial, rosette-like malformations.We are greatly indebted for the technical assistance of Miss C. Gutmann, Mrs I. Hempfling and Mrs K. Pfaff. 相似文献
98.
99.
Zusammenfassung Acetylcholin wirkt als Aktivator auf Oxydationsreaktionen mit Wasserstoffperoxyd in alkalischer Lösung. Solche Wirkungen auf die Chemilumineszenz des Luminols (3-Aminophthalhydrazid), auf die Oxydation des Indols, Benzidins und o-Dianizidins wurden durch Messungen der Lumineszenzintensität (), bzw, der Extinktion (E) näher untersucht. 相似文献
100.
Summary Mammary glands of the white mouse in different stages of lactation were fixed in Carnoy's fluid and the sections stained with Gallocyanin-chromalum für microscopic observation. After dislocation of the nucleolus to the nuclear membrane or the formation of a heterochromatic pathway between nucleolus and nuclear membrane the extrusion of nucleolar substance into the cytoplasm was observed. 相似文献