Browsing by Subject "complexes"

Now showing 1 - 3 of 3
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    Gold(I)-Catalyzed Amination of Allylic Alcohols with Cyclic Ureas and Related Nucleophiles
    (2010) Mukherjee, Paramita; Widenhoefer, Ross A
    A 1:1 mixture of [P(t-Bu)(2)-o-biphenyl]AuCl and AgSbF6 catalyzes the Intermolecular amination of allylic alcohols with 1-methylimidazolidin-2-one and related nucleophiles that, in the case of gamma-unsubstituted or gamma-methyl-substituted allylic alcohols, occurs with high gamma-regloselectivity and syn-stereoselectivity.
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    Principal-component-based multivariate regression for genetic association studies of metabolic syndrome components
    (2010) Mei, Hao; Chen, Wei; Dellinger, Andrew; He, Jiang; Wang, Meng; Yau, Canddy; Srinivasan, Sathanur R; Berenson, Gerald S
    Background: Quantitative traits often underlie risk for complex diseases. For example, weight and body mass index (BMI) underlie the human abdominal obesity-metabolic syndrome. Many attempts have been made to identify quantitative trait loci (QTL) over the past decade, including association studies. However, a single QTL is often capable of affecting multiple traits, a quality known as gene pleiotropy. Gene pleiotropy may therefore cause a loss of power in association studies focused only on a single trait, whether based on single or multiple markers. Results: We propose using principal-component-based multivariate regression (PCBMR) to test for gene pleiotropy with comprehensive evaluation. This method generates one or more independent canonical variables based on the principal components of original traits and conducts a multivariate regression to test for association with these new variables. Systematic simulation studies have shown that PCBMR has great power. PCBMR-based pleiotropic association studies of abdominal obesity-metabolic syndrome and its possible linkage to chromosomal band 3q27 identified 11 susceptibility genes with significant associations. Whereas some of these genes had been previously reported to be associated with metabolic traits, others had never been identified as metabolism-associated genes. Conclusions: PCBMR is a computationally efficient and powerful test for gene pleiotropy. Application of PCBMR to abdominal obesity-metabolic syndrome indicated the existence of gene pleiotropy affecting this syndrome.
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    Time-dependent wavepacket investigation of state-to-state reactive scattering of Cl with para-H-2 including the open-shell character of the Cl atom
    (2010) Sun, Z; Zhang, DH; Alexander, MH
    We describe a time-dependent wavepacket based method for the calculation of the state-to-state cross sections for the Cl+H-2 reaction including all couplings arising from the nonzero spin and electronic orbital angular momenta of the Cl atom. Reactant-product decoupling allows us to use a physically correct basis in both the reactant and the product arrangements. Our calculated results agree well with the experimental results of Yang and co-workers. We also describe a model with two coupled potential energy surfaces, which includes the spin-orbit coupling, which is responsible for the largest non-Born-Oppenheimer effects in the Cl+H-2 reaction but neglects the off-diagonal electronically diabatic coupling and all Coriolis couplings due to the electronic spin and orbital angular momenta. The comparison of the results of the full six-state and two-state models with an electronically adiabatic (one-state) description reveals that the latter describes well the reaction out of the ground spin-orbit state, while the two-state model, which is computationally much faster than the full six-state model, describes well the reaction from both the ground and excited spin-orbit states.