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81.
Kumar Vijay Kushwaha Vikram Gandhi Yashika Mishra Sujeet K. Charde Vaibhav Jagtap Chandrashekhar Babu G. Singh Arjun Singh Ravindra Srikanth Narayanam 《平面色谱法杂志一现代薄层色谱法》2022,35(1):23-33
JPC – Journal of Planar Chromatography – Modern TLC - A new, simple, selective, sensitive, precise, and robust high-performance thin-layer chromatography (HPTLC) method for the... 相似文献
82.
83.
Doyon JB Pattanayak V Meyer CB Liu DR 《Journal of the American Chemical Society》2006,128(7):2477-2484
The laboratory evolution of enzymes with tailor-made DNA cleavage specificities would represent new tools for manipulating genomes and may enhance our understanding of sequence-specific DNA recognition by nucleases. Below we describe the development and successful application of an efficient in vivo positive and negative selection system that applies evolutionary pressure either to favor the cleavage of a desired target sequence or to disfavor the cleavage of nontarget sequences. We also applied a previously described in vitro selection method to reveal the comprehensive substrate specificity profile of the wild-type I-SceI homing endonuclease. Together these tools were used to successfully evolve mutant I-SceI homing endonucleases with altered DNA cleavage specificities. The most highly evolved enzyme cleaves the target mutant DNA sequence with a selectivity that is comparable to wild-type I-SceI's preference for its cognate substrate. 相似文献
84.
Vikas Vikram Singh Abdel Lisser 《Journal of Optimization Theory and Applications》2018,178(3):998-1013
We consider a two-player random bimatrix game where each player is interested in the payoffs which can be obtained with certain confidence. The payoff function of each player is defined using a chance constraint. We consider the case where the entries of the random payoff matrix of each player jointly follow a multivariate elliptically symmetric distribution. We show an equivalence between the Nash equilibrium problem and the global maximization of a certain mathematical program. The case where the entries of the payoff matrices are independent normal/Cauchy random variables is also considered. The case of independent normally distributed random payoffs can be viewed as a special case of a multivariate elliptically symmetric distributed random payoffs. As for Cauchy distribution, we show that the Nash equilibrium problem is equivalent to the global maximization of a certain quadratic program. Our theoretical results are illustrated by considering randomly generated instances of the game. 相似文献
85.
Mudit M Behery FA Wali VB Sylvester PW El Sayed KA 《Natural product communications》2010,5(10):1623-1626
4-Hydroxyphenylmethylene hydantoin (PMH, 1), isolated from the Red Sea sponge Hemimycale arabica, and delta-tocotrienol (3), isolated from the tocotrienol-rich fraction of palm oil, are important antimetastatic and antiproliferative natural products that proved effective against metastatic prostate and breast cancers, respectively. New fluorescent derivatives of PMH (2) and delta-tocotrienol (4) were synthesized by Steglich esterification. Both 2 and 4 retained good anti-migratory and antiproliferative activities, respectively. Fluorescent analogues 2 and 4 can be used for the identification of molecular targets of 1 and 3 in tumor cell cultures. 相似文献
86.
Carole A Winterhalter Justyna Teverovsky Patricia Wilson Jeremiah Slade Wendy Horowitz Edward Tierney Vikram Sharma 《IEEE transactions on information technology in biomedicine》2005,9(3):402-406
The focus of this paper is on the development of textile-based wearable electronics that can be integrated into military protective clothing. A materials and manufacturing survey was conducted to determine the best performing and most durable materials to withstand the rigors of textile manufacturing and potential military use. Narrow woven technology was selected as one of the most promising textile manufacturing methods. A working wearable narrow fabric version of the Universal Serial Bus (USB), as well as a radiating conductor, were successfully developed and fabricated. A circular knit T-shirt with an integrated spiral bus was also developed. Military products developed include components of a personal area network providing data and power transport, and a body-borne antenna integrated into a load-bearing vest. 相似文献
87.
Vikram Vinayak Karve Jordi Espín Mehrdad Asgari Samuel Van Gele Emad Oveisi Wendy Lee Queen 《Advanced functional materials》2023,33(21):2212283
Herein, novel carbons that, owing to a high density of micropores (up to 79%) and N-content (up to 14.9%), offering exciting potential for post-combustion CO2 capture are reported. Given that little is known about how starting materials impact the structure and performance of carbons, three different microporous materials are pyrolyzed. These include a Co-(metal-organic framework) (MOF), a Co-MOF-polymer composite, and a coordination polymer derived from the same monomer and cobalt ions. Notably, the cobalt, which is required to drive the polymerization, is subsequently leached from the carbons via acid for its reuse in MOF synthesis. Next, various metrics including CO2 capacity, selectivity, isosteric heat of adsorption, breakthrough time and cyclability are assessed. The acid treated carbons adsorb 0.21, 0.99, and 1.11 mmol CO2 g−1, respectively, (313 K, 0.15 bar) with CO2/N2 selectivity ranging from 37 to 52. Due to superior capacity, the polymer-derived carbons also reveal impressive breakthrough times in simulated flue gas mixtures (15% CO2/85% N2, 80% RH, 313 K) ranging from 33 to 40 min g−1. Similar performance is also observed under dry conditions and after pre-saturation with water for 1.5 h. Remarkably, no loss in working capacity is observed after 100 CO2 TSA cycles (313 K/393 K). 相似文献
88.
Vikram B. Patel Anami R. Patel Manisha C. Patel Datta B. Madamwar 《Applied biochemistry and biotechnology》1993,43(1):45-50
The effect of several salts, FeCl3, NiCl2, CoCl2, CuCl2, and ZnCl2, on anaerobic digestion of water hyacinth-cattle dung was examined. Among the salts studied, FeCl3 caused a more than 60% increase in gas production with a high methane content. 相似文献
89.
Diamanti SJ Khanna V Hotta A Yamakawa D Shimizu F Kramer EJ Fredrickson GH Bazan GC 《Journal of the American Chemical Society》2004,126(34):10528-10529
Block copolymerization of ethylene with 5-norbornen-2-yl acetate (1) by the nickel catalyst system [N-(2,6-diisopropylphenyl)-2-(2,6-diisopropylphenylimino)propanamide]Ni(eta1-CH2Ph)(PMe3) (2) and Ni(COD)2 (bis(1,4-cyclooctadiene)nickel) (3) produces a variety of block copolymer structures that demonstrate microphase separation. Typical block copolymerizations were carried out in an autoclave charged with a solution of the catalyst mixture and 1 (0.15 M) in toluene. The autoclave was sealed and exposed to PC2H4 = 50 psi for a period of time (T1). A pressure jump to PC2H4 = 1100 psi was then applied and the reaction allowed to proceed for another predetermined interval (T2). Independent experiments were performed to isolate and examine the molecular weight and comonomer composition of the first block. Narrow molecular weight distributions and the increase of polymer molecular weight with increases in T1 or T2 are consistent with a product in which an initial block is formed at low ethylene pressures and quantitatively converted to a block copolymer by the jump to high pressure. Transmission electron microscopy confirms that the materials are microphase separated. 相似文献
90.
Ramachandran R Ladizhansky V Bajaj VS Griffin RG 《Journal of the American Chemical Society》2003,125(50):15623-15629
The rotational resonance width (R2W) experiment is a constant-time version of the rotational resonance (R2) experiment, in which the magnetization exchange is measured as a function of sample spinning frequency rather than the mixing time. The significant advantage of this experiment over conventional R2 is that both the dipolar coupling and the relaxation parameters can be independently and unambiguously extracted from the magnetization exchange profile. In this paper, we combine R2W with two-dimensional 13C-13C chemical shift correlation spectroscopy and demonstrate the utility of this technique for the site-specific measurement of multiple 13C-13C distances in uniformly labeled solids. The dipolar truncation effects, usually associated with distance measurements in uniformly labeled solids, are considerably attenuated in R2W experiments. Thus, R2W experiments are applicable to uniformly labeled biological systems. To validate this statement, multiple 13C-13C distances (in the range of 3-6 A) were determined in N-acetyl-[U-13C,15N]l-Val-l-Leu with an average precision of +/-0.5 A. Furthermore, the distance constraints extracted using a two-spin model agree well with the X-ray crystallographic data. 相似文献