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101.
Motivated by experiments on single-headed kinesin KIF1A, we develop a model of intracellular transport by interacting molecular motors. It captures explicitly not only the effects of adenosine triphosphate hydrolysis, but also the ratchet mechanism which drives individual motors. Our model accounts for the experimentally observed single-molecule properties in the low-density limit and also predicts a phase diagram that shows the influence of hydrolysis and Langmuir kinetics on the collective spatiotemporal organization of the motors. Finally, we provide experimental evidence for the existence of domain walls in our in vitro experiment with fluorescently labeled KIF1A. 相似文献
102.
Nine 1-[2-(1-substituted)ethyl-3-benzothienyl]-2-(2-methyl-3-benzothienyl)hexafluorocyclopentenes (4-substituted benzoyloxy, N-arylcarbamoyloxy, and aryloxycarbonyloxy) were synthesized. They showed diastereoselective photochromic ring closure upon UV irradiation. Among them, 4-nitrophenoxycarbonyloxy-substituted compound recorded a remarkable 94% diastereomer excess with 91% conversion to the closed form. 相似文献
103.
Suzuki M Nakajima Y Yumoto M Kimura M Shirai H Hanabusa K 《Organic & biomolecular chemistry》2004,2(8):1155-1159
Organogels are formed through a conventional organogelation involving a heating process and an in situ organogelation at room temperature. The conventional organogelation is carried out by dissolution of gelators by heating, while the in situ organogelation is performed by mixing of highly reactive methyl 2,6-diisocyanatohexanoate (LDI) or 2-isocyanatoethyl 2,6-diisocyanatohexanoate (LTI) and alkylamines. The in situ organogelation produced the organogels within several seconds after mixing. The organogels prepared by the in situ organogelation showed quite similar FT-IR spectra and SEM photographs to those formed by conventional organogelation. Moreover, the in situ organogelation using LTI and octylamine as well as dodecylamine produced organogels of acetone, ethyl acetate, and acetonitrile that gelators 5 and 6 cannot gel through conventional organogelation. 相似文献
104.
Morita Y Nishida S Kobayashi T Fukui K Sato K Shiomi D Takui T Nakasuji K 《Organic letters》2004,6(9):1397-1400
[structure: see text] A bowl-shaped neutral radical with a corannulene system has been designed and synthesized for the first time as a stable solid in air. An unequivocal characterization of the electronic properties of the radical shows that an appreciable amount of spin delocalization extends onto the corannulene unit's curved surface. 相似文献
105.
Construction of eight-membered carbocyclic rings via the intramolecular B-alkyl Suzuki-Miyaura cross-coupling reaction has been studied. This protocol proved its potency through the formation of the eight-membered ring possessing a quaternary carbon on its ring in high yield, affording promise of a new access to the eight-membered ring of Taxol. [reaction: see text] 相似文献
106.
An optimal portfolio/control problem is considered for a two-dimen\-sional
model in finance. A pair consisting of the wealth process and cumulutative
consumption process driven by a geometric Lévy process is controlled by adapted
processes. The value function appears and turns out to be a viscosity solution
to some integro-differential equation, by using the Bellman principle. 相似文献
107.
For a knotted surface in -space, its generic projection into -space has branch points as its singularities, and its successive projection into -space has fold points and cusps as its singularities. In this paper, we show that for non-orientable knotted surfaces, the numbers of branch points and cusps can be minimized by isotopy.
108.
Yoshinori Miyazaki Nobuyoshi Asai Yasushi Kikuchi DongSheng Cai Yasuhiko Ikebe. 《Mathematics of Computation》2004,73(246):719-730
In this paper, it is first given as a necessary and sufficient condition that infinite matrices of a certain type have double eigenvalues. The computation of such double eigenvalues is enabled by the Newton method of two variables. The three-term recurrence relations obtained from its eigenvalue problem (EVP) subsume the well-known relations of (A) the zeros of ; (B) the zeros of ; (C) the EVP of the Mathieu differential equation; and (D) the EVP of the spheroidal wave equation. The results of experiments are shown for the three cases (A)-(C) for the computation of their ``double pairs'.
109.
110.
We investigate the suppression factor and the azimuthal correlation function for high p(T) hadrons in central Au+Au collisions at sqrt[s(NN)]=200 GeV by using a dynamical model in which hydrodynamics is combined with explicitly traveling jets. We study the effects of parton energy loss in a hot medium, intrinsic k(T) of partons in a nucleus, and p (perpendicular) broadening of jets on the back-to-back correlations of high p(T) hadrons. Parton energy loss is found to be a dominant effect on the reduction of the awayside peaks in the correlation function. 相似文献