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Dimer Consisting (dimer + consisting)
Selected AbstractsConvergence radii of the polarization expansion of intermolecular potentialsINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 15 2009William H. Adams Abstract A new method is presented to evaluate convergence radii of the polarization expansion of interaction energies for pairs of atoms or molecules. The method is based on an analysis of the variation of the perturbed state vector as a function of the coupling constant , and does not require a calculation of perturbation corrections to high order. The convergence radii at infinite interatomic/intermolecular distances R, as well as a remarkably accurate representation of the R dependence of the convergence radii are obtained from simple calculations involving only monomer wave functions. For the interaction of the lithium and hydrogen atoms, the obtained convergence radii agree well with those obtained previously from the large-order calculations of Patkowski et al. (Patkowski et al., J Chem Phys, 2002, 117, 5124), but are expected to be considerably more accurate. Rigorous upper bounds and reasonable approximations to the convergence radii at R = , are obtained for the pairs of lithium, beryllium, boron, neon, and sodium atoms, as well as for the dimer consisting of two LiH molecules. For all the systems studied, the convergence radii are significantly smaller than the unity and rapidly decrease with the increase of the nuclear charge. It is hoped that the results of this investigation will help to analyze and eventually to compute the convergence radii of the symmetry-adapted perturbation theories which utilize the same partitioning of the Hamiltonian as the polarization expansion. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 [source] A cotton ascorbate peroxidase is involved in hydrogen peroxide homeostasis during fibre cell developmentNEW PHYTOLOGIST, Issue 3 2007Hong-Bin Li Summary ,,Reactive oxygen species (ROS) play important roles in multiple physiological processes such as cellular signalling and stress responses, whereas, the hydrogen peroxide (H2O2) scavenging enzyme ascorbate peroxidase (APX) participates in the regulation of intracellular ROS levels. ,,Here, a cotton (Gossypium hirsutum) cytosolic APX1 (GhAPX1) was identified to be highly accumulated during cotton fibre elongation by proteomic analysis. GhAPX1 cDNA contained an open reading frame of 753-bp encoding a protein of 250 amino acid residues. When GhAPX1 was expressed in Escherichia coli, the purified GhAPX1 was a dimer consisting of two identical subunits with a molecular mass of 28 kDa. GhAPX1 showed the highest substrate specificity for ascorbate. ,,Quantitative real-time polymerase chain reaction (PCR) analyses showed that GhAPX1 was highly expressed in wild-type 5-d postanthesis fibres with much lower transcript levels in the fuzzless-lintless mutant ovules. Treating in vitro cultured wild-type cotton ovules with exogenous H2O2 or ethylene induced the expression of GhAPX1 and hence increased total APX activity proportionally, followed by extended fibre cell elongation. ,,These data suggest that GhAPX1 expression is upregulated in response to an increase in cellular H2O2 and ethylene. GhAPX1 encodes a functional enzyme that is involved in hydrogen peroxide homeostasis during cotton fibre development. [source] Ethyl 2-amino-4- tert -butyl-1,3-thiazole-5-carboxylate and 6-methylimidazo[2,1- b]thiazole,2-amino-1,3-thiazole (1/1)ACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2004Daniel E. Lynch The structure of ethyl 2-amino-4- tert -butyl-1,3-thiazole-5-carboxylate, C10H16N2O2S, (I), and the structure of the 1:1 adduct 6-methylimidazo[2,1- b]thiazole,2-amino-1,3-thiazole (1/1), C6H6N2S·C3H4N2S, (II), have been determined. The molecules in (I) associate via a hydrogen-bonded R(8) dimer consisting of N,H,N interactions, with the hydrogen-bonding array additionally involving N,H,O interactions to one of the carboxylate O atoms. The 2-aminothiazole molecules in (II) also associate via an N,H,N hydrogen-bonded R(8) dimer, with an additional N,H,N interaction to the Nsp2 atom of the imidazothiazole moiety, creating hydrogen-bonded quartets. [source] Reconstitution of anti-HIV effector functions of primary human CD8 T,lymphocytes by transfer of HIV-specific ,,,TCR genesEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 12 2004Takamasa Ueno Abstract We redirected the antigen specificity of primary human CD8 T,cells by retrovirus-mediated transduction of genes encoding ,,,TCR specific to HIV-1 Pol protein. A large polyclonal population of TCR-transduced CD8 T,cells showed substantial cytotoxic and cytokine production activities toward target cells either pulsed with the peptide or infected with HIV-1, and their functional activities were comparable to those of the parental CTL clone. Peptide fine-specificity and promiscuous recognition of HLA class,I supertypes of the parental CTL clone were also preserved in the TCR-transduced cells. There were no signs of allogeneic responses in these cells, although hybrid TCR dimers consisting of transduced TCR and endogenous TCR were suspected to have been formed in these cells, as the effect of transgene expression on the surface expression of the desired TCR was limited. Moreover, the TCR-transduced cells showed potent inhibitory activity against HIV-1 replication in vitro, although the differential surface expression of the desired TCR resulted in differential functional avidity of individual TCR-transduced cells toward the peptide-pulsed target cells. These data suggest that the reconstitution of HIV-specific immunoreactive T,cells engineered by genetic transfer of HIV-specific TCR is a potential alternative to immunotherapeutic applications against HIV infections. [source] | ||||||||||