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151.
Entangled coherent states (ECSs) with relative phase equal to the phase shift between two coherent states are constructed. We study the degree of entanglement and the nonclassical features exhibited by the so-constructed states keeping in view their role in quantum information processing (QIP).  相似文献   
152.
Plants respond to stress in part by modulating gene expression either constitutively or in an inducible manner which ultimately leads to the restoration of cellular homeostasis, detoxification of toxins, and recovery of growth. Upon introduction to various elicitors such as pathogen-associated molecular patterns, a massive reprogramming of plant gene expression is initiated. Differential display PCR offers rapid and multiple comparisons of gene expression to various stress durations and intensities. Nigella sativa has acclaimed many medicinal properties in traditional medicine. To explore the underlying molecular mechanisms in response to stress in the plants, Fusarium solani (a fungus) stress was induced at different time intervals ranging from 0 to 48 h. RNA was subjected to complementary DNA (cDNA) synthesis followed by PCR using different sets of anchored primers and arbitrary primers. The expression was visualized after silver staining on urea-PAGE. Out of the 23 upregulated re-amplified cDNA products, ten differential fragments showed significant homologies with domains related to cellular metabolism, signal transduction, and disease resistance. Such genes could be an informative source for developing genetically improved breeds under infectious stress.  相似文献   
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Plants are under constant assault by biotic and abiotic agents. When an elicitor is prologued, an immense reprogramming of plant gene expression and defense responses are initiated, which could be a natural source for potential drug development and insertional mutagenesis. In this regard, differential expression analysis of a medicinal plant Moringa oleifera was performed for bioactive genes at seedling stage, using differential display-RT-PCR technique. Infected seedlings with a fungus Fusarium solani collected at different time intervals, showed a massive change in their gene expression profile. The data analysis revealed that at least 150 pathogen-induced and about 60 suppressed genes were differentially expressed at 8-h postinoculation of the biotic stress. Fifty-five selective genes were disunited and reamplified. Sequence analysis of these potential genes illustrated that these genes had properties of some induced peroxidase mRNA, cell proliferation, others were mitogen activated protein kinases, ribosomal protein genes, defense regulating genes, and a few also had structural properties. Further studies about the utility of these genes in plant metabolism could assist to develop improved transgenic breeds with enhanced value of infection tolerance not only of M. oleifera but of other cultivars also.  相似文献   
155.
By using the quantum tunneling approach over semiclassical approximations, we study the quantum corrections to the Hawking temperature, entropy and Bekenstein-Hawking entropy-area relation for a black hole lying on a brane.  相似文献   
156.
We investigate multiple-soliton pattern formations in a figure-of-eight passively mode-locked fiber laser. Operation in the anomalous dispersion regime with a double-clad fiber amplifier allows generation of up to several hundreds of solitons per round trip. We report the observation of remarkable soliton distributions: soliton gas, soliton liquid, soliton polycrystal, and soliton crystal, thus indicating the universality of such complexes.  相似文献   
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Abstract

The four-component reaction among arylhydrazine, alkyl acetoacetate derivatives, alkyl isocyanides, and dialkyl acetylenedicarboxylates, leading to the formation of dialkyl 2-[(Z)-(alkylamino)(3-alkyl-5-oxo-1-phenyl-1,5-dihydro-4H-pyrazol-4-ylidene)methyl] fumarates is described. The structure of target compounds was confirmed using X-ray diffraction study. These pyrazolone derivatives contain a highly twisted exocyclic 1,3-butadiene moiety with skew (??=?87°) geometry.  相似文献   
160.
Summary We have carried out low temperature magnetic susceptibility measurements and a redetermination of the crystal and molecular structure of bis(1,5-diazacyclooctane)nickel(II) perchlorate dihydrate from three-dimensional intensity data collected on a CAD4 diffractometer. The structure was refined by full-matrix least-squares to the R value of 6.3% for 1501 observed reflections. The positions of the hydrogen atoms were obtained from the diffraction data. Contrary to our earlier conclusions drawn by inspection of molecular models of bis(diazacyclooctane) complexes, the axial sites in the actual crystal structure are open for ligation. The Ni-N bonds are, however, sterically protected by the coplanar N-H bonds, allowing maximum ligand-field stabilization for the squareplanar geometry around the nickel atom. The observed magnetic transition from a diamagnetic state at room temperature to a paramagnetic state at 78 K is explained on the basis of long-range exchange interactions along sterically unshieldedz axis. The crystal structure is compared with other similar structures.  相似文献   
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