Quark recombination model for polarizations in inclusive hyperon productions at high energy

We investigate the transverse polarization of hyperons produced by the photon induced reactions using the quark recombination model. This model reproduces polarizations of hadrons produced by the hadron-hadron collisions and accounts for the origin of the empirical rule by DeGrand and Miettinen. We find significant polarizations in the hyperon photoproduction by applying this model to the \gamma N \ra \Lam $(\Sigma^{0}) + X$ reaction.Comment: Latex, 6 page with 6 figures, to be published in proceedings of APCTP Workshop on "Strangeness Nuclear Physics", Feb. 19-22, Seoul, Kore

Effect of Plant Diversity on Ruminal Degradability of Goats Grazing in a Semi-natural Pasture

Poster Session

重症慢性肝疾患における高γク口ブリン血症の意義 : とくに血清グ口プリン/IgG とICG除去能との相聞に関連して

BACKGROUND/AIMS:Although hyperglobulinemia is frequently detected in severe chronic liver diseases (CLD) such as liver cirrhosis (LC), the mechanism for this is still uncertain. Hyperglobulinemia may represent a functional aspect of the liver.METHODOLOGY: The correlation between serum globulin (GLB) level and each of various liver function tests including the indocyanine green (ICG) retention rate at 15 min (ICGR15) was studied using 146 patients with liver dysfunction. The correlations among GLB, IgG and ICGR15 were also studied in other 32 patients with LC, in whom the glycosylation pattern of IgG was determined by enzyme-linked immunosorbent assay to detect terminal galactose (Gal) and neuraminic acid (NA) using biotinylated lectins.RESULTS:GLB level was predominantly correlated with ICGR15 (r = 0.449) among various liver function tests in 146 patients with liver dysfunction. In the 32 patients with LC, strong positive correlations between GLB and IgG (r = 0.875), between GLB and ICGR15 (r = 0.435), and between IgG and ICGR15 (r = 0.557) were evident. The glycosylation pattern of IgG showed that the proportions of both Gal and NA were inversely correlated with serum IgG levels (r = -0.516 and -0.390, respectively) in these patients. Significant decreases of the proportions were found in patients with IgG elevation (> 20 g/L, n = 13).CONCLUSIONS:The correlation between GLB and ICGR15 suggested that hyperglobulinemia is related to a common dysfunction estimated by ICG clearance, which represents mainly the liver's blood flow and removal capacity. The removal of immunoglobulins by the liver may be impaired in patients with severe liver dysfunction because the liver is a major catabolic site for immunoglobulins. The glycation pattern suggested that the proportions of asialo IgG and agalactosyl IgG were increased in the LC patients with IgG elevation possibly by deficient receptor-mediated removal in the liver. Although further investigations will be needed, hyperglobulinemia could be predictive for a certain impaired hepatic function estimated by ICG clearance in severe CLD such as LC.博士（医学）・乙第1301号・平成24年7月26日Hepato Gastroenterology © 200

Adaptive Threonine Increase in Transmembrane Regions of Mitochondrial Proteins in Higher Primates

BACKGROUND: The mitochondrial (mt) gene tree of placental mammals reveals a very strong acceleration of the amino acid (AA) replacement rate and a change in AA compositional bias in the lineage leading to the higher primates (simians), in contrast to the nuclear gene tree. Whether this acceleration and compositional bias were caused by adaptive evolution at the AA level or directional mutation pressure at the DNA level has been vigorously debated. METHODOLOGY/PRINCIPAL FINDINGS: Our phylogenetic analysis indicates that the rate acceleration in the simian lineage is accompanied by a marked increase in threonine (Thr) residues in the transmembrane helix regions of mt DNA-encoded proteins. This Thr increase involved the replacement of hydrophobic AAs in the membrane interior. Even after accounting for lack of independence due to phylogeny, a regression analysis reveals a statistical significant positive correlation between Thr composition and longevity in primates. CONCLUSION/SIGNIFICANCE: Because crucial roles of Thr and Ser in membrane proteins have been proposed to be the formation of hydrogen bonds enhancing helix-helix interactions, the Thr increase detected in the higher primates might be adaptive by serving to reinforce stability of mt proteins in the inner membrane. The correlation between Thr composition in the membrane interior and the longevity of animals is striking, especially because some mt functions are thought to be involved in aging

Core set approach to reduce uncertainty of gene trees

BACKGROUND: A genealogy based on gene sequences within a species plays an essential role in the estimation of the character, structure, and evolutionary history of that species. Because intraspecific sequences are more closely related than interspecific ones, detailed information on the evolutionary process may be available by determining all the node sequences of trees and provide insight into functional constraints and adaptations. However, strong evolutionary correlations on a few lineages make this determination difficult as a whole, and the maximum parsimony (MP) method frequently allows a number of topologies with a same total branching length. RESULTS: Kitazoe et al. developed multidimensional vector-space representation of phylogeny. It converts additivity of evolutionary distances to orthogonality among the vectors expressing branches, and provides a unified index to measure deviations from the orthogoality. In this paper, this index is used to detect and exclude sequences with large deviations from orthogonality, and then selects a maximum subset ("core set") of sequences for which MP generates a single solution. Once the core set tree is formed whose all the node sequences are given, the excluded sequences are found to have basically two phylogenetic positions on this tree, respectively. Fortunately, since multiple substitutions are rare in intra-species sequences, the variance of nucleotide transitions is confined to a small range. By applying the core set approach to 38 partial env sequences of HIV-1 in a single patient and also 198 mitochondrial COI and COII DNA sequences of Anopheles dirus, we demonstrate how consistently this approach constructs the tree. CONCLUSION: In the HIV dataset, we confirmed that the obtained core set tree is the unique maximum set for which MP proposes a single tree. In the mosquito data set, the fluctuation of nucleotide transitions caused by the sequences excluded from the core set was very small. We reproduced this core-set tree by simulation based on random process, and applied our approach to many sets of the obtained endpoint sequences. Consequently, the ninety percent of the endpoint sequences was identified as the core sets and the obtained node sequences were perfectly identical to the true ones

Robust Time Estimation Reconciles Views of the Antiquity of Placental Mammals

BACKGROUND: Molecular studies have reported divergence times of modern placental orders long before the Cretaceous–Tertiary boundary and far older than paleontological data. However, this discrepancy may not be real, but rather appear because of the violation of implicit assumptions in the estimation procedures, such as non-gradual change of evolutionary rate and failure to correct for convergent evolution. METHODOLOGY/PRINCIPAL FINDINGS: New procedures for divergence-time estimation robust to abrupt changes in the rate of molecular evolution are described. We used a variant of the multidimensional vector space (MVS) procedure to take account of possible convergent evolution. Numerical simulations of abrupt rate change and convergent evolution showed good performance of the new procedures in contrast to current methods. Application to complete mitochondrial genomes identified marked rate accelerations and decelerations, which are not obtained with current methods. The root of placental mammals is estimated to be ∼18 million years more recent than when assuming a log Brownian motion model. Correcting the pairwise distances for convergent evolution using MVS lowers the age of the root about another 20 million years compared to using standard maximum likelihood tree branch lengths. These two procedures combined revise the root time of placental mammals from around 122 million years ago to close to 84 million years ago. As a result, the estimated distribution of molecular divergence times is broadly consistent with quantitative analysis of the North American fossil record and traditional morphological views. CONCLUSIONS/SIGNIFICANCE: By including the dual effects of abrupt rate change and directly accounting for convergent evolution at the molecular level, these estimates provide congruence between the molecular results, paleontological analyses and morphological expectations. The programs developed here are provided along with sample data that reproduce the results of this study and are especially applicable studies using genome-scale sequence lengths

Analysis of Cumulant Moments in High Energy Hadron-Hadron Collisions by Truncated Multiplicity Distributions

Oscillatory behavior of cumulant moments obtained from the experimental data in $pp$ collisions and $\bar{p}p$ collisions are analyzed by the modified negative binomial distribution (MNBD) and the negative binomial distribution (NBD). Both distributions well describe the cumulant moments obtained from the data. This fact shows sharp contrast to the result in $e^+e^-$ collisions, which is described by the the MNBD much better than by the NBD.Comment: 7 pages, Latex type, 7 figure

O(a)-improved quark action on anisotropic lattices and perturbative renormalization of heavy-light currents

We investigate the Symanzik improvement of the Wilson quark action on anisotropic lattices. Taking first a general action with nearest-neighbor and clover interactions, we study the mass dependence of the ratio of the hopping parameters, the clover coefficients, and an improvement coefficient for heavy-light vector and axial vector currents. We show how tree-level improvement can be achieved. For a particular choice of the spatial Wilson coupling, the results simplify, and $O(m_0a_\tau)$ improvement is possible. (Here $m_0$ is the bare quark mass and $a_\tau$ the temporal lattice spacing.) With this choice we calculate the renormalization factors of heavy-light bilinear operators at one-loop order of perturbation theory employing the standard plaquette gauge action.Comment: 26 pages, 8 figure