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111.
Primitive polynomials,singer cycles and word-oriented linear feedback shift registers 总被引:1,自引:0,他引:1
Sudhir?R.?GhorpadeEmail author Sartaj?Ul?Hasan Meena?Kumari 《Designs, Codes and Cryptography》2011,58(2):123-134
Using the structure of Singer cycles in general linear groups, we prove that a conjecture of Zeng et al. (Word-Oriented Feedback
Shift Register: σ-LFSR, 2007) holds in the affirmative in a special case, and outline a plausible approach to prove it in the general case.
This conjecture is about the number of primitive σ-LFSRs of a given order over a finite field, and it generalizes a known formula for the number of primitive LFSRs, which,
in turn, is the number of primitive polynomials of a given degree over a finite field. Moreover, this conjecture is intimately
related to an open question of Niederreiter (Finite Fields Appl 1:3–30, 1995) on the enumeration of splitting subspaces of
a given dimension. 相似文献
112.
Archana ChaudharyVeena Dhayal Meena NagarRakesh Bohra Shaikh M. MobinPradeep Mathur 《Polyhedron》2011,30(5):821-831
Reactions of [Ti(OPri)4] with various oximes, in anhydrous refluxing benzene yielded complexes of the type [Ti{OPri}4−n{L}n], where, n = 1-4 and LH = (CH3)2CNOH (1-4), C9H16CNOH (5-8) and C9H18CNOH (9-12). The compounds were characterized by elemental analyses, molecular weight measurements, FAB-mass, FT-IR and NMR (1H, 13C{1H}) spectral studies. The FAB-mass spectra of mono- (1), and di- (2), (6), (10) substituted products indicate their dimeric nature and that of tri- (3) and tetra- (4), (8) substituted derivatives suggest their monomeric nature. Crystal and molecular structure of [Ti{ONC10H16}4·2CH2Cl2] (8A) suggests that the oximato ligands bind the metal in a dihapto η2-(N, O) manner, leading to the formation of an eight coordinated species. Thermogravimetric curves of (3), (6) and (10) exhibit multi-step decomposition with the formation of TiO2 as the final product in each case, at 900 °C. Low temperature (∼600 °C) sol-gel transformations of (2), (3), (4), (6), (7) and (8) yielded nano-sized titania (a), (b), (c), (d), (e) and (f), respectively. Formation of anatase phase in all the titania samples was confirmed by powder XRD patterns, FT-IR and Raman spectroscopy. SEM images of (a), (b), (c), (d), (e) and (f) exhibit formation of nano-grains with agglomer like surface morphologies. Compositions of all the titania samples were investigated by EDX analyses. The absorption spectra of the two representative samples, (a) and (f) indicate an energy band gap of 3.17 eV and 3.75 eV, respectively. 相似文献
113.
Meena Sahai 《代数通讯》2013,41(3):817-828
ABSTRACT Let K be a field of characteristic p ≠ 2 and let G be any group. A characterization of group algebras KG satisfying the Lie identity [[x,y],[u,v],[z,t]] = 0 for all x,y,u,v,z,t ? KG is obtained. 相似文献
114.
115.
Dr. Shubhankar Gadre M. Manikandan Prakash Duari Sushant Chhatar Astha Sharma Subhash Khatri Dr. Jyoti Kode Madan Barkume Nirmal Kumar Kasinathan Manasi Nagare Meena Patkar Arvind Ingle Dr. Mukesh Kumar Prof. Ullas Kolthur-Seetharam Dr. Malay Patra 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(46):e202201259
Despite phenomenal clinical success, the efficacy of platinum anticancer drugs is often compromised due to inherent and acquired drug resistant phenotypes in cancers. To circumvent this issue, we designed two heterobimetallic platinum (II)-ferrocene hybrids that display multi-pronged anticancer action. In cancer cells, our best compound, 2 , platinates DNA, produces reactive oxygen species, and has nucleus, mitochondria, and endoplasmic reticulum as potential targets. The multi-modal mechanism of action of these hybrid agents lead to non-apoptotic cell death induction which enables circumventing apoptosis resistance and significant improvement in platinum cross resistance profile. Finally, in addition to describing detail mechanistic insights, we also assessed its stability in plasma and demonstrate anticancer efficacy in an in vivo A2780 xenograft model. Strikingly, compared to oxaliplatin, our compound displays better tolerability, safety profile and efficacy in vivo. 相似文献
116.
Neha Sawhney Kumar Mukesh Sharma Amit K. Sharma Meena 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(4):756-761
Russian Journal of Physical Chemistry A - The viscosities of aqueous solutions of L-alanine and L-valine with non-steroid anti-inflammatory drug dolonex (0.020, 0.040, 0.060 mol kg–1) have... 相似文献
117.
We study the Dyson rank function N(r, 3; n), the number of partitions of n with rank \(\equiv r \pmod 3\). We investigate the convexity of these functions. We extend N(r, 3; n) multiplicatively to the set of partitions, and we determine the maximum value when taken over all partitions of size n. 相似文献
118.
The solution of the steady laminar incompressible nonsimilar magneto-hydrodynamic boundary layer flow and heat transfer problem
with viscous dissipation for electrically conducting fluids over two-dimensional and axisymmetric bodies with pressure gradient
and magnetic field has been presented. The partial differential equations governing the flow have been solved numerically
using an implicit finite-difference scheme. The computations have been carried out for flow over a cylinder and a sphere.
The results indicate that the magnetic field tends to delay or prevent separation. The heat transfer strongly depends on the
viscous dissipation parameter. When the dissipation parameter is positive (i.e. when the temperature of the wall is greater
than the freestream temperature) and exceeds a certain value, the hot wall ceases to be cooled by the stream of cooler air
because the ‘heat cushion’ provided by the frictional heat prevents cooling whereas the effect of the magnetic field is to
remove the ‘heat cushion’ so that the wall continues to be cooled. The results are found to be in good agreement with those
of the local similarity and local nonsimilarity methods except near the point of separation, but they are in excellent agreement
with those of the difference-differential technique even near the point of separation. 相似文献
119.
120.
All four 2',3'-dideoxy-3'-thio-nucleosides (ddtNTPs) function as substrates for the Y410F mutant of Deep Vent (exo-) DNA polymerase. Not only are the ddtNTPs incorporated to form the N + 1 product, but further elongations are observed in which the key step is attack of the 3'-thiol on the 5'-triphosphate. Although other polymerases are likely to differ in their use of the ddtNTPs, there does not appear to be a fundamental prohibition against using a thiol nucleophile on a phosphate anhydride electrophile. The syntheses of four ddtNTPs (C, T, A, G) are described. [structure: see text] 相似文献