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91.
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93.
UV light leads to release of different secretory factors from irradiated cells of which some of them have been characterized. We have reported earlier that cells exposed to the supernatant medium from irradiated cells were resistant to killing by some genotoxic agents. In this study, we present our finding that demonstrates DNA damage induced by UV or H(2)O(2) is lowered on prior exposure to the UV released factors (UVRF). Production of ROS in cells and lipid peroxidation was also lowered. It was found that treatment of unexposed cells with UVRF present in the supernatant medium altered the antioxidant defense activity in cells. Significant was the increase in catalase (CAT) and Cu-Zn superoxide dismutase (SOD) activity, whereas glutathione peroxidase (GPx) and reduced glutathione (GSH) levels remained unaffected. Cells exposed to UVRF prior to UV or H(2)O(2) treatment also experienced such upregulation; however, the remarkable increase in the GPx activity exhibited by these cells was not observed in cells exposed to H(2)O(2) or UV alone. It appears that exposure to UVRF tinkered with antioxidant defense in cells to facilitate its proliferation upon assault by an agent that can produce oxidative damage. 相似文献
94.
M. Kumar Raju P. Sugathan T. Seshi Reddy B. V. Thirumala Rao S. Muralithar R. P. Singh R. K. Bhowmik P. V. Madhusudhana Rao 《Journal of Radioanalytical and Nuclear Chemistry》2012,294(1):53-57
The high spin level structure of 73As nucleus is studied by populating the nucleus in 64Ni(12C,p2n)73As reaction. Level scheme is revised significantly. Positive parity sequence is extended up to 33/2+ and a negative parity side band is identified and extended up to high spins 37/2?. In addition about 15 new energy levels and a total of about 25 new gamma transitions were placed in the level scheme. 相似文献
95.
Anuj Bhowmik Jiling Cao Nicholas C. Yannelis 《Journal of Mathematical Analysis and Applications》2014
A general model of a pure exchange differential information economy is studied. In this economic model, the space of states of nature is a complete probability measure space, the space of agents is a finite measure space, and the commodity space is the Euclidean space. Under some appropriate and standard assumptions on agents' characteristics, results on continuity and measurability of the aggregate preferred correspondence similar to that of Aumann [8] are established. These results together with other techniques are then employed to prove the existence of a maximin rational expectations equilibrium (maximin REE) of the economic model. 相似文献
96.
S Jana P Bhowmik S Chattopadhyay 《Dalton transactions (Cambridge, England : 2003)》2012,41(34):10145-10149
A novel thiocyanate bridged one-dimensional copper(i) polymer, [CuL(μ-1,1,3-SCN)](n) (L = 5,6-diphenyl-2,3-dihydropyrazine), has been synthesized and characterized by X-ray crystallography. The complex features a copper(i) stair-step polymeric coordination network with a Cu(2)S(2) core. The complex shows strong fluorescence. 相似文献
97.
98.
Bishanka Brata Bhowmik Sumanta Gupta Ranjan Gangopadhyay 《Optics Communications》2012,285(16):3483-3486
We have introduced and comprehensively analyzed a novel scheme of simultaneous demodulation and dispersion compensation of wavelength division multiplexed (WDM) non-return-to zero (NRZ) differential phase shift keying (DPSK) optical link using an optical ring resonator (ORR) based filter. Using extensive numerical simulation we have demonstrated the transmission of 10.7 Gb/s WDM DPSK channels having 50 GHz and 100 GHz spacing over 400 km of unrepeatered reach at 20 dB optical-signal-to-noise-ratio (OSNR) to achieve a bit error rate (BER) of 10? 3. 相似文献
99.
The present work reports ferromagnetism by doping magnetic Mn atoms in the diamagnetic ZnO matrix and the ferromagnetism has been extended up to 640 K in nano-grained Zn0.95Mn0.05O samples. The bulk and nano-grained samples were stabilized in hexagonal crystal structure with space group p63mc. The grain size and lattice strain of the samples were estimated from room temperature XRD spectrum. Surface morphology of the samples was examined at room temperature using SEM picture and EDX spectrum. The ferromagnetism of the bulk material shows enhancement in nano-grained samples, which was mainly due to the solution of Mn atoms into the lattice sites of ZnO by mechanical milling. The enhancement of magnetic moment and ferromagnetic ordering temperature with reduction in grain size has been understood in terms of the core-shell structure and existing theoretical models. The present work also demonstrated the role of surface spin disorder on the enhancement of ferromagnetism in Zn0.95Mn0.05O nanograins. 相似文献
100.
Tumpa Bhattacharjee Somen Chanda Sarmishtha Bhattacharyya Swapan Kumar Basu R.K. Bhowmik S. Muralithar R.P. Singh N.S. Pattabiraman S.S. Ghugre U. Datta Pramanik S. Bhattacharya 《Nuclear Physics A》2005,750(2-4):199-217
The high spin states in the N=79 odd–odd 136La nucleus have been investigated by in-beam γ-spectroscopic techniques following the 130Te(11B, 5n)136La reaction at E=52 MeV using an array, consisting of eight Compton-suppressed clover germanium detectors. Thirty nine new γ rays have been assigned to 136La on the basis of γ ray singles and γγ-coincidence data. The level scheme of 136La has been extended above the known 115 ms isomer upto an excitation energy of 4.6 MeV and spin 18. Thirty one new levels have been proposed and spin-parity assignments for most of the newly proposed levels have been made on the basis of the deduced asymmetry ratios and polarisation information for the de-exciting transitions. The observed positive parity yrast band has been compared with the theoretical calculation, done within the framework of particle rotor coupling model (PRM) where the two odd quasi-particles are coupled to an axially symmetric core. The level structure has been discussed in the light of the known systematics of the neighbouring N=79 isotonic nuclei. 相似文献