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81.
Lee N Benichi H Takeno Y Takeda S Webb J Huntington E Furusawa A 《Science (New York, N.Y.)》2011,332(6027):330-333
We report on the experimental quantum teleportation of strongly nonclassical wave packets of light. To perform this full quantum operation while preserving and retrieving the fragile nonclassicality of the input state, we have developed a broadband, zero-dispersion teleportation apparatus that works in conjunction with time-resolved state preparation equipment. Our approach brings within experimental reach a whole new set of hybrid protocols involving discrete- and continuous-variable techniques in quantum information processing for optical sciences. 相似文献
82.
ZhanQingcai SaidoKoji KatoAkira 《农业科学与技术》2003,4(1):8-15
The quantitative trait loci(QTLs)for cold tolerance relative characters were identified with microsatellite markers.Ten QTLs located on chromosome1,3,4,5,6,8,9,11(two)and 12were detected for seedling height at different low temperature.Only 2 of these were detected at the same locus at four environments.1 was significant at three environments.6 were significant at two environments and 1 was significant at one environment.Seven QTLs located on chromosome 1(two),2(two),5,6,8were found for ow temperature chlorosis resistance and five QTLs located on chromosome 3,4,7,8,11resistant to chilling injury.The amount of variation explained by indivdual QTL ranged from 4.85%to 49.34%,There was no linkage relationship among the three characters.which indicates seediling cold tolerance is a complex character and is controlled by different QTLs. 相似文献
83.
Using long-duration, three-dimensional magnetohydrodynamic simulation, we found that the magnetic dipole field generated by a dynamo action in a rotating spherical shell repeatedly reverses its polarity at irregular intervals (that is, punctuated reversal). Although the total convection energy and magnetic energy alternate between a high-energy state and a low-energy state, the dipole polarity can reverse only at high-energy states where the north-south symmetry of the convection pattern is broken and the columnar vortex structure becomes vulnerable. Another attractive finding is that the quadrupole mode grows, exceeding the dipole mode before the reversal; this may help to explain how Earth's magnetic field reverses. 相似文献
84.
Brain catecholamines: relation to defense reaction evoked by acute brainstem transection in cat 总被引:1,自引:0,他引:1
The concentration of noradrenaline, but not serotonin, in the brainstem of cats is reduced 3 hours after the production of a defense reaction by supracollicular decerebration, even when movements and changes in blood pressure are abolished by transection of the spinal cord. After midcollicular decerebration, which does not elicit a defense reaction, noradrenaline concentrations do not change. The decrease in its concentration accompanying the defense reaction produtced by brain lesions probably reflects activity, in this behavior, of neturons containinig noradrenaline. 相似文献
85.
Kinoshita T Miura A Choi Y Kinoshita Y Cao X Jacobsen SE Fischer RL Kakutani T 《Science (New York, N.Y.)》2004,303(5657):521-523
86.
Differential cytosine methylation of repeats and genes is important for coordination of genome stability and proper gene expression. Through genetic screen of mutants showing ectopic cytosine methylation in a genic region, we identified a jmjC-domain gene, IBM1 (increase in bonsai methylation 1), in Arabidopsis thaliana. In addition to the ectopic cytosine methylation, the ibm1 mutations induced a variety of developmental phenotypes, which depend on methylation of histone H3 at lysine 9. Paradoxically, the developmental phenotypes of the ibm1 were enhanced by the mutation in the chromatin-remodeling gene DDM1 (decrease in DNA methylation 1), which is necessary for keeping methylation and silencing of repeated heterochromatin loci. Our results demonstrate the importance of chromatin remodeling and histone modifications in the differential epigenetic control of repeats and genes. 相似文献
87.
van Schaik CP Ancrenaz M Borgen G Galdikas B Knott CD Singleton I Suzuki A Utami SS Merrill M 《Science (New York, N.Y.)》2003,299(5603):102-105
Geographic variation in some aspects of chimpanzee behavior has been interpreted as evidence for culture. Here we document similar geographic variation in orangutan behaviors. Moreover, as expected under a cultural interpretation, we find a correlation between geographic distance and cultural difference, a correlation between the abundance of opportunities for social learning and the size of the local cultural repertoire, and no effect of habitat on the content of culture. Hence, great-ape cultures exist, and may have done so for at least 14 million years. 相似文献
88.
Yurimoto H Abe K Abe M Ebihara M Fujimura A Hashiguchi M Hashizume K Ireland TR Itoh S Katayama J Kato C Kawaguchi J Kawasaki N Kitajima F Kobayashi S Meike T Mukai T Nagao K Nakamura T Naraoka H Noguchi T Okazaki R Park C Sakamoto N Seto Y Takei M Tsuchiyama A Uesugi M Wakaki S Yada T Yamamoto K Yoshikawa M Zolensky ME 《Science (New York, N.Y.)》2011,333(6046):1116-1119
Meteorite studies suggest that each solar system object has a unique oxygen isotopic composition. Chondrites, the most primitive of meteorites, have been believed to be derived from asteroids, but oxygen isotopic compositions of asteroids themselves have not been established. We measured, using secondary ion mass spectrometry, oxygen isotopic compositions of rock particles from asteroid 25143 Itokawa returned by the Hayabusa spacecraft. Compositions of the particles are depleted in (16)O relative to terrestrial materials and indicate that Itokawa, an S-type asteroid, is one of the sources of the LL or L group of equilibrated ordinary chondrites. This is a direct oxygen-isotope link between chondrites and their parent asteroid. 相似文献
89.
Akira Otsuki Takehiko Omi Shinya Hashimoto Morihiro Aizaki Noriko Takamura 《Water, air, and soil pollution》1994,76(3-4):383-396
A method for HPLC determination of phycocyanin in phytoplankton samples using gelchromatography with a fluorescence detector was developed to examine the use of phycocyanin as an index of the appearance and progress of cyanobacterial blooms in highly eutrophic lake. At least two types of phycocyanin with different molecular weights, each spectroscopically different from phycoerythrin and allophycocyanin, were found in natural phytoplankton samples. Changes in phycocyanin concentrations were clearly coupled to changes in chlorophyll-a concentrations during June to October while cyanobacterial blooms were occurring. The chlorophyll-a to phycocyanin relationship was linear at chlorophyll-a concentrations of less than 250 μg L?1. The relationship between cyanobacterial carbon and phycocyanin concentration was also linear, suggesting that phycocyanin content may be a useful index of cyanobacterial biomass in highly eutrophic lakes where large cyanobacterial blooms occur. 相似文献
90.
Spore-breaking capabilities of collembolans and their feeding habitat within sporocarps 总被引:2,自引:0,他引:2
To examine the relationship between the spore-breaking capability of collembolans and their localization within fungal sporocarps we investigated the proportion of broken spores in the feces of four collembolan species of the genus Hypogastrura using the spores of Hypsizygus marmoreus and analyzed the spatial distribution of the collembolan species within sporocarps as an index of their feeding habits. The collembolan species with a higher capability to break spores were observed more frequently from the spore-bearing surfaces of sporocarps. The collembolan species with a lower capability to break spores were found more frequently from the non-spore-bearing interiors of the sporocarps. These results suggest that the relative value of spores in the diet varied with the capability of collembolans to break spores. 相似文献