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101.
Let R be a commutative complex unital semisimple Banach algebra with the involution ·*{\cdot ^\star} . Sufficient conditions are given for the existence of a stabilizing solution to the H
∞ Riccati equation when the matricial data has entries from R. Applications to spatially distributed systems are discussed. 相似文献
102.
Gene silencing using RNA interference (RNAi) has become a prominent biological tool for gene annotation, pathway analysis, and target discovery in mammalian cells. High-throughput screens conducted using whole-genome siRNA libraries have uncovered rich sets of new genes involved in a variety of biological processes and cellular models of disease. However, high-throughput RNAi screening is not yet a mainstream tool in life science research because current screening platforms are expensive and onerous. Miniaturizing the RNAi screening platform to reduce cost and increase throughput will enable its widespread use and harness its potential for rapid genome annotation. With this aim, we have combined semi-conductor microfabrication and nanolitre dispensing techniques to develop miniaturized electroporation-ready microwell arrays loaded with siRNA molecules in which multiplexed gene knockdown can be achieved. Arrays of microwells are created using high-aspect ratio biocompatible photoresists on optically transparent and conductive Indium-Tin Oxide (ITO) substrates with integrated micro-electrodes to enable in situ electroporation. Non-contact inkjet microarraying allows precise dispensing of nanolitre volumes into the microwell structures. We have achieved parallel electroporation of multiple mammalian cells cultured in these microwell arrays and observed efficient knockdown of genes with surface-bound, printed siRNAs. Further integration of microfabrication and non-contact nanolitre dispensing techniques described here may enable single-substrate whole-genome siRNA screening in mammalian cells. 相似文献
103.
Vibhute AM Vidyasagar A Sarala S Sureshan KM 《Chemical communications (Cambridge, England)》2012,48(18):2448-2450
We report the first, general and selective acylation of the least reactive hydroxyl group among six secondary hydroxyl groups of inositol in high yield, using very cheap and easy-to-make H(2)SO(4)-silica as the catalyst, providing easy access to bioactive molecules. 相似文献
104.
The methylene-free ring synthesis of 1,3-cyclohexadienes has been expanded to include a diverse set of functional group-rich terminal and internal alkynes. [reaction: see text] 相似文献
105.
Pravin Chavan Amol Salve Shivaji Jadhav Dattatraya Pansare Megha Rai 《Journal of heterocyclic chemistry》2020,57(3):1228-1235
In this study, new series of azetidine derivatives were synthesized ( 4a-n ) from isoniazide ( 1 ), Aromatic aldehydes ( 2a-n ), dihydropyran ( 3 ) using SnCl2 catalyst, via one pot multicomponent reaction/cycloaddition reaction. The synthesized azetidine derivatives were characterized by IR, 1H NMR and 13C NMR and have been screened for antimicrobial, antituberculosis and anti-inflammatory activities. In relation to Staphylococcus aureus (ATCC 25923) promising antibacterial activity was shown, compounds 4e and 4k , followed by compounds 4h , 4n , 4f , 4g and 4l . The synthesized azetidine derivatives, 4a , 4e , 4j and 4m (with zone 12 mm) displayed antituberculosis activity. But its lower potential than, the standard streptomycin (with zone 18 mm). Further 4d compound alone displayed similar activity. 相似文献
106.
A new iron fluoride assisted convenient and efficient strategy for the preparation of 4H-pyrimido[2,1-b]benzothiazoles derivatives in solvent-free media is described. The reactions can be performed at low-catalyst loadings with excellent functional group tolerance. The catalyst can be readily recovered and reused for next reaction for at least three runs without any significant impact on the yields of the products. The easy recovery of the catalyst and high yield of the products make the protocol attractive, sustainable, and economic. 相似文献
107.
Adam B. Hall Stephen L. Coy Amol Kafle James Glick Erkinjon Nazarov Paul Vouros 《Journal of the American Society for Mass Spectrometry》2013,24(9):1428-1436
A miniature, planar, differential ion mobility spectrometer (DMS) was interfaced to an LCQ classic ion trap to conduct selective ion filtration prior to mass analysis in order to extend the dynamic range of the trap. Space charge effects are known to limit the functional ion storage capacity of ion trap mass analyzers and this, in turn, can affect the quality of the mass spectral data generated. This problem is further exacerbated in the analysis of mixtures where the indiscriminate introduction of matrix ions results in premature trap saturation with non-targeted species, thereby reducing the number of parent ions that may be used to conduct MS/MS experiments for quantitation or other diagnostic studies. We show that conducting differential mobility-based separations prior to mass analysis allows the isolation of targeted analytes from electrosprayed mixtures preventing the indiscriminate introduction of matrix ions and premature trap saturation with analytically unrelated species. Coupling these two analytical techniques is shown to enhance the detection of a targeted drug metabolite from a biological matrix. In its capacity as a selective ion filter, the DMS can improve the analytical performance of analyzers such as quadrupole (3D or linear) and ion cyclotron resonance (FT-ICR) ion traps that depend on ion accumulation.
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108.
Vivek Chavan P. C. Kalsi Amol Mhatre 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(1):273-276
The bulk-etch rates of a newly developed track detector which is a copolymer of N-allyloxycarbonyl diethanolamine-bis allylcarbonate
(NADAC) and allyl diglycol carbonate (ADC) [NADAC-ADC (1:1, w/w)] have been determined at different temperatures to deduce
its activation energy. The energy of activation is found to be (0.93 ± 0.07) eV. This compares very well with the values of
activation energy reported in the literature for the most commonly used nuclear track detectors. The effects of gamma irradiation
on this new detector in the dose range of 47.0–145.0 kGy have also been studied using bulk etch, UV–visible spectroscopic,
and thermogravimetric analysis (TGA) techniques. The activation energy for bulk etching calculated from bulk etch rates measurements
at different temperatures, optical band gaps determined from the UV–visible spectra, and the values of onset temperature of
decomposition (T0) calculated from TGA curves were found to decrease with the increase in gamma dose. These results have been explained on
the basis of scission of the detector due to gamma irradiation. 相似文献
109.
Kendhale AM Poniman L Dong Z Laxmi-Reddy K Kauffmann B Ferrand Y Huc I 《The Journal of organic chemistry》2011,76(1):195-200
The synthesis of quinoline-derived helically folded aromatic oligoamides functionalized by various chiral functions at their N-terminus is reported. When a (1S)-(-)-camphanyl moiety was introduced, it was found that helix handedness was completely shifted to right-handed helicity (de > 99%), in both protic and nonprotic solvents. The absolute helical sense and the de values were unambiguously characterized by using (1)H NMR, circular dichroism (CD), and X-ray crystallography. The crystal structure of these compounds allowed us to propose a rationale for the efficiency of helix handedness induction based on a combination of steric factors and intramolecular hydrogen bonding. 相似文献
110.
A simple,efficient,and general method has been developed for the synthesis ofα-amino nitriles.Oxalic acid as a BrФnsted acid promotes the addition of TMSCN to various imines(generated in situ). 相似文献