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141.
Farha Naz Mohd Asad Pawan Malhotra Asimul Islam Faizan Ahmad Md Imtaiyaz Hassan 《Applied biochemistry and biotechnology》2014,172(6):2838-2848
Microtubule-associated protein/microtubule affinity-regulating kinase 4 (MARK4) is a member of the family Ser/Thr kinase and involved in numerous biological functions including microtubule bundle formation, nervous system development, positive regulation of programmed cell death, cell cycle control, cell polarity determination, cell shape alterations, cell division etc. For various biophysical and structural studies, we need this protein in adequate quantity. In this paper, we report a novel cloning strategy for MARK4. We have cloned MARK4 catalytic domain including 59 N-terminal extra residues with unknown function and catalytic domain alone in PQE30 vector. The recombinant MARK4 was expressed in the inclusion bodies in M15 cells. The inclusion bodies were solubilized effectively with 1.5 % N-lauroylsarcosine in alkaline buffer and subsequently purified using Ni–NTA affinity chromatography in a single step with high purity and good concentration. Purity of protein was checked on sodium dodecyl sulphate–polyacrylamide gel electrophoresis and identified by using mass spectrometry immunoblotting. Refolding of the recombinant protein was validated by ATPase assay. Our purification procedure is quick, simple and produces adequate quantity of proteins with high purity in a limited step. 相似文献
142.
The thermal decompositions of polystyrene, polyoxyethylene glycol and mixtures of the two have been studied by thermogravimetry. The composition of the mixtures both before and after decomposition, as well as changes in the molecular weights and polydispersities of the polystyrene components, were followed by gel permeation chromatography. Ultra-violet spectrophotometry also served to determine the polystyrene contents of the mixtures after decomposition. The presence of polyoxyethylene glycol as a reaction promoter was found to have a pronounced effect on the decomposition of polystyrene, believed to be initiated, in large part, by intermolecular transfer. The depolymerization that follows takes place more rapidly probably because of the presence of a large number of active fragments. The overall activation energy, calculated by the method of Flynn and Wall, supports this hypothesis, being lower in the presence of polyoxyethylene glycol and higher in its absence. 相似文献
143.
144.
145.
T. Haupt P. V. K. S. Baba S. Banerjee M. Bardadin-Otwinowska K. W. J. Barnham T. Coghen A. Devanand K. Dziunikowska S. N. Ganguli H. Gerhold P. Girtler Y. Goldschmidt-Clermont R. Göttgens G. L. Kaul M. W. Krasny D. Kuhn P. K. Malhotra F. Mandl L. K. Mangotra A. B. Michalowska D. R. O. Morrison Y. Prakash R. T. Ross K. Shankar G. Singh K. Sudhakar M. Szczekowski P. R. S. Wright 《Zeitschrift fur Physik C Particles and Fields》1985,28(1):57-63
146.
Summary. The global dynamics of flexible spinning discs are studied. The discs studied are parametrically excited in their spin rate,
and have imperfections that cause symmetry-breaking. After determining the equations of motion in a suitable form, the energy-phase
method is employed to show the existence of chaotic dynamics by identifying multipulse jumping orbits in the perturbed phase
space. We provide restrictions on the damping, forcing, and symmetry-breaking parameters in order for these complicated dynamics
to occur. The dissipative version of the energy-phase method predicts a wider range of values for which chaotic dynamics occurs
than the traditional Melnikov method. The results are then discussed in terms of the physical motion of the spinning disc
system. The multipulse orbits are manifested in the physical system as a shifting between two different nodal configurations
of the disc. When the motion is chaotic, an observer will see a random jumping between the two nodal configurations of the
disc.
Received February 7, 2000; accepted November 18, 2001 相似文献
147.
Ohne Zusammenfassung 相似文献
148.
Bobeldijk I Bouwhuis M Ireland DG de Jager CW Jans E de Jonge N Kasdorp WJ Konijn J Lapikás L van Leeuwe JJ van der Meer RL Nooren GJ Passchier E Schroevers M van der Steenhoven G Steijger JJ Theunissen JA van Uden MA de Vries H de Vries R de Witt Huberts PK Blok HP van den Brink HB Dodge GE Harakeh MN Hesselink WH Kalantar-Nayestanaki N Pellegrino A Spaltro CM Templon JA Hicks RS Kelly JJ Marchand C 《Physical review letters》1994,73(20):2684-2687
149.
ω-(2,6-Dimethyl-4-pyrimidinylthio-(4), 2-methyl-4-quinazolinylthio-(9), and 4-oxo-2-quinazo-linylthio)-(10) acetophenones with hydrochloric or perchloric acid provide 2,5-diaryl-1,4-dithiins (7) whereas α)-(6-methyl-4-pyrimidinylthio) acetophenones (11) with aq HCl/HClO4, or POCl3 followed by hydrolysis provide 1-(4-aryl-2-thiazolyl)-2-propanones (12). Likewise, 2-(6-methyl-4-pyrimidinylthio) cyclohexanone (13) give the thiazole derivative (14). 相似文献
150.
An improved gas—liquid chromatographic method based on the separation of N-trifluoroacetyl n-butyl esters of amino acids on a “two-column” setup --- Tabsorb and Tabsorb HAC --- was developed for the identification and estimation of amino acids in pine needles (Pinus banksiana Lamb.). A comparative study was made of various available gas—liquid chromatographic methods for separation and estimation of amino acids from pine needle extracts. 相似文献