6,673 research outputs found
TACC3-ch-TOG track the growing tips of microtubules independently of clathrin and Aurora-A phosphorylation
No full textThe interaction between TACC3 (transforming acidic coiled coil protein 3) and the microtubule polymerase ch-TOG (colonic, hepatic tumor overexpressed gene) is evolutionarily conserved. Loading of TACC3–ch-TOG onto spindle microtubules requires the phosphorylation of TACC3 by Aurora-A kinase and the subsequent interaction of TACC3 with clathrin to form a microtubule binding surface. Whether there is a pool of TACC3–ch-TOG that is independent of clathrin in human cells, and what is the function of this pool, are open questions. Here, we report that TACC3 is recruited to the plus-ends of microtubules by its association with ch-TOG and that this pool is independent of phosphorylation and binding to clathrin. The plus-end binding of TACC3–ch-TOG persists in interphase and we propose that one cellular function of TACC3–ch-TOG is to modulate cell migration. We also describe the distinct subcellular pools of TACC3, ch-TOG and clathrin. TACC3 is often described as a centrosomal protein, but we show that there is no significant population of TACC3 at centrosomes. The delineation of distinct protein pools reveals a simplified view of how these proteins are organized and controlled by post-translational modification
Green function hierarchy for open shells.
No full textIn many systems containing open shell ions, the wave function of the ions cannot be described by a single Slater determinant. This invalidates standard many-body theory and requires the use of nonequilibrium quantum field theory with initial correlations. Quantum group techniques are used here to deal with this combinatorially complex theory. The hierarchy of interacting Green functions for general initial correlations is derived and the case of a system with two-particle correlations is treated in detail
The many-body Green function of degenerate systems
No full text4 pages, 1 figureInternational audienceA rigorous non perturbative adiabatic approximation of the evolution operator in the many-body physics of degenerate systems is derived. This approximation is used to solve the long-standing problem of the choice of the initial states of H0 leading to eigenstates of H0+V for degenerate systems. These initial states are eigenstates of P0 V P0, where P0 is the projection onto a degenerate eigenspace of H0. This result is used to give the proper definition of the Green function, the statistical Green function and the non-equilibrium Green function of degenerate systems. The convergence of these Green functions is established
Multiple-Scattering Theory of Magnetic EXAFS
No full textThis paper discusses various issues of the multiple-scattering theory of magnetic circular dichroism (MCD)
in the x-ray range, especially at the K-edge of 3d transition metals. Using a sernirelativistic expansion of the Dirac Green
function, we show how MCD can be calculated and related to orbital momentum. Moreover, the rigid band model will
be used to relate the high-energy behaviour of MCD to the exchange energy. Finally, we generalise our approach to the
case of orbital polarisation, which was found to be relevant to MCD
4f orbital and spin magnetism in cerium intermetallic compounds studied by magnetic circular x-ray dichroism
No full textLes diminutifs basques avec ch
No full textSe presentan formaciones similares a los diminutivos vascos con "ch" en España y América latina. Se dan ejemplosThe author introduces similar formations to the Basque diminutive "ch" in Spain and Latin America. Examples are provide
COUPLING OF THE C-H STRETCH TO LARGE-AMPLITUDE TORSION AND INVERSION MOTIONS: COMPARISON OF CHCH, CHOH AND CHNH
No full textAuthor Institution: Department of Polymer Science and Department of Chemistry, The University of Akron; Department of Chemistry, The University of Akron, OH 44325In each of the title molecules, torsional and inversion tunneling occurs between six equivalent minima. Coupling of these degrees of freedom to the CH stretch occurs via variation of the C-H stretching force constants as a function of the torsional () and inversion () angles. Maps of the couplings have been computed at the MP2/6-311++G(3df,2p) level. Both the single bond CH stretch force constants and the bilinear couplings between CH bonds are presented as a function of and . Although the torsional barriers differ by more than a factor of 20, the torsion-inversion-vibration coupling patterns are very similar for CHNH and CHCH. On the other hand, the torsion-inversion-vibration coupling in the charged species CHOH is much weaker
Reply to the Ch. Lagrange’s note
No full textThe author answers to a Ch. Lagrange’s note who refutes his theory on the diurnal nutation.L’auteur répond à une note de Ch. Lagrange qui réfute sa théorie sur la nutation diurne
NATURE OF TORSION-INVERSION COUPLING IN CHNH, CHOH AND CHCH
No full textAuthor Institution: Department of Chemistry, The University of Akron, OH; 44325-3601Two-dimensional torsion-inversion surfaces for methylamine, protonated methanol and ethyl radical were calculated and fit to a function containing a polynomial in the inversion angle() and trigonometric functions of the torsional angle(). Calculations were done at the B3LYP, MP2, and CCSD(T) levels with the 6-311++G(d,p) and 6-311++G(3df, 2p) basis sets and partial optimization. CHNH, CHOH and CHCH have G symmetry with 6-equivalent minima which are located by the various calculations at inversion angles 6.5 to 11; 42 to 45.5 and 52.5 to 55 degrees respectively on either side of planar. The three molecules have very different barriers to inversion ranging from no barrier for CHCH to 838 cm for CHOH to 1837 cm for CHNH. The dominant torsion-inversion coupling term in all cases has the form
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