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81.
It is shown that the analysis of fusion barrier distributions is not always an unambiguous test or a ‘fingerprint’ of the
structure information of the colliding nuclei. Examples are presented with same fusion barrier distributions for nuclei having
different structures. The fusion excitation functions for 16O+208Pb, using the coupled reaction channel (CRC) method and correct structure information, have been analysed. The barrier distributions
derived from these excitation functions including many of the significant channels are featureless, although these channels
have considerable effects on the fusion excitation function. However, a simultaneous analysis of the fusion, elastic and quasi-elastic
channels would fix the structure and the reaction unambiguously. 相似文献
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Juwar Doley Lakshya Veer Singh G. Ravi Kumar Aditya Prasad Sahoo Lovleen Saxena Uttara Chaturvedi Shikha Saxena Rajiv Kumar Prafull Kumar Singh R. S. Rajmani Lakshman Santra S. K. Palia S. Tiwari D. R. Harish Arvind Kumar G. S. Desai Smita Gupta Shishir K. Gupta A. K. Tiwari 《Applied biochemistry and biotechnology》2014,172(1):497-508
The canine parvovirus type 2 (CPV-2) causes an acute disease in dogs. It has been found to induce cell cycle arrest and DNA damage leading to cellular lysis. In this paper, we evaluated the apoptotic potential of the “new CPV-2a” in MDCK cells and elucidated the mechanism of the induction of apoptosis. The exposure of MDCK cells to the virus was found to trigger apoptotic response. Apoptosis was confirmed by phosphatidylserine translocation, DNA fragmentation assays, and cell cycle analysis. Activation of caspases-3, -8, -9, and -12 and decrease in mitochondrial potential in CPV-2a-infected MDCK cells suggested that the CPV-2a-induced apoptosis is caspase dependent involving extrinsic, intrinsic, and endoplasmic reticulum pathways. Increase in p53 and Bax/Bcl2 ratio was also observed in CPV-2a-infected cells. 相似文献
87.
The creation of superpositions of hole states via single-photon ionization using attosecond extreme-ultraviolet pulses is studied with the time-dependent configuration-interaction singles (TDCIS) method. Specifically, the degree of coherence between hole states in atomic xenon is investigated. We find that interchannel coupling not only affects the hole populations, but it also enhances the entanglement between the photoelectron and the remaining ion, thereby reducing the coherence within the ion. As a consequence, even if the spectral bandwidth of the ionizing pulse exceeds the energy splittings among the hole states involved, perfectly coherent hole wave packets cannot be formed. For sufficiently large spectral bandwidth, the coherence can only be increased by increasing the mean photon energy. 相似文献
88.
The multiwavelength anomalous diffraction (MAD) method is used to determine phase information in x-ray crystallography by employing anomalous scattering from heavy atoms. X-ray free-electron lasers (FELs) show promise for revealing the structure of single molecules or nanocrystals, but the phase problem remains largely unsolved. Because of the ultrabrightness of x-ray FEL, samples experience severe electronic radiation damage, especially to heavy atoms, which hinders direct implementation of MAD with x-ray FELs. Here, we propose a generalized version of MAD phasing at high x-ray intensity. We demonstrate the existence of a Karle-Hendrickson-type equation in the high-intensity regime and calculate relevant coefficients with detailed electronic damage dynamics of heavy atoms. The present method offers a potential for ab initio structural determination in femtosecond x-ray nanocrystallography. 相似文献
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Santra S Kaittanis C Santiesteban OJ Perez JM 《Journal of the American Chemical Society》2011,133(41):16680-16688
Herein we describe the design and synthesis of a folate-doxorubicin conjugate with activatable fluorescence and activatable cytotoxicity. In this study we discovered that the cytotoxicity and fluorescence of doxorubicin are quenched (OFF) when covalently linked with folic acid. Most importantly, when the conjugate is designed with a disulfide bond linking the targeting folate unit and the cytotoxic doxorubicin, a targeted activatable prodrug is obtained that becomes activated (ON) within the cell by glutathione-mediated dissociation and nuclear translocation, showing enhanced fluorescence and cellular toxicity. In our novel design, folic acid acted as both a targeting ligand for the folate receptor as well as a quencher for doxorubicin's fluorescence. 相似文献
90.
A Highly Modular One‐Pot Multicomponent Approach to Functionalized Benzo[b]phosphole Derivatives
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Bin Wu Dr. Mithun Santra Prof. Naohiko Yoshikai 《Angewandte Chemie (International ed. in English)》2014,53(29):7543-7546
Benzo[b]phosphole derivatives have attracted significant attention for their unique optoelectronic properties with potential for application in materials science. Herein we report a modular approach to a benzo[b]phosphole derivative based on a one‐pot sequential coupling of an arylzinc reagent, an alkyne, dichlorophenylphosphine (or phosphorus trichloride and a Grignard reagent), and an oxidant (for example H2O2, S, or Se). The approach allows for the construction of a library of previously inaccessible, structurally diverse benzo[b]phosphole derivatives with unprecedented ease. 相似文献