Genetic Polymorphisms of the Coding Region (Exon 6) of Calpastatin in Indonesian Sheep

Calpastatin (CAST) is an indigenous inhibitor of calpain that involved in regulation of protein turn over and growth. The objective of this research was to identify genetic polymorphisms in the entire exon 6 of calpastatin gene in Indonesian local sheep. A PCR-SSCP method was carried out to identify genetic variation of CAST gene. In total 258 heads of local sheep from 8 populations were investigated, three groups of samples were Thin Tail Sheep (TTS) from Sukabumi, Jonggol, and Kissar. The rest samples were Priangan sheep (PS) from Margawati (Garut meat type) and Wanaraja (Garut fighting type) and Fat Tail Sheep (FTS) from Donggala, Sumbawa, and Rote islands. SSCP analysis revealed that three different SSCP patterns corresponded to three different alleles in the CAST locus (CAST-1, 2, and 3 allele) with five different genotypes. Genetic variation between local sheep populations were calculated based on genotypic and allelic frequencies. Most populations studied were polymorphic, with genotype frequencies of CAST-11, CAST-12, CAST-22, CAST-32, and CAST-33 were 0.286, 0.395, 0.263, 0.046, and 0.007 respectively. CAST-1 and 2 alleles were most commonly found in all populations with total frequency was 0.970, while CAST-3 was a rare allele 0.030 and only found in TTS population. Variation in the CAST gene could be used for the next research as genetic diversity study or to find any association between CAST polymorphism with birth weight, growth trait and carcass quality in Indonesian local sheep

The Doped Two Chain Hubbard Model

The properties of the two-chain Hubbard Model doped away from half-filling are investigated. The charge gap is found to vanish, but a finite spin gap exists over a range of interchain hopping strength $t_\perp$. In this range, there are modified $d_{x^2-y^2}$--like pairing correlations whose strength is correlated with the size of the spin gap. It is found that the pair field correlations are enhanced by the onsite Coulomb interaction U.Comment: 10 pages and 5 postscript figures, RevTeX 3.0, UCI-CMTHE-94-0

A model universe with variable dimension: Expansion as decrumpling

We propose a model universe, in which the dimension of the space is a continuous variable, which can take any real positive number. The dynamics leads to a model in which the universe has no singularity. The difference between our model and the standard Friedman-Robertson-Walker models become effective for times much before the presently accepted age of the universe.Comment: 12 pages, emTeX version 3.0, no figure

Three-Nucleon Bound State in a Spin-Isospin Dependent Three Dimensional Approach

A spin-isospin dependent Three-Dimensional approach based on momentum vectors for formulation of the three-nucleon bound state is presented in this paper. The three-nucleon Faddeev equations with two-nucleon interactions are formulated as a function of vector Jacobi momenta, specifically the magnitudes of the momenta and the angle between them with the inclusion of the spin-isospin quantum numbers, without employing a partial wave decomposition. As an application the spin-isospin dependent Faddeev integral equations are solved with Bonn-B potential. Our result for the Triton binding energy with the value of -8.152 MeV is in good agreement with the achievements of the other partial wave based methods.Comment: 24 pages, 1 figure, 7 tables. Major changes; version to appear in Physical Review

Tetris is Hard, Even to Approximate

In the popular computer game of Tetris, the player is given a sequence of tetromino pieces and must pack them into a rectangular gameboard initially occupied by a given configuration of filled squares; any completely filled row of the gameboard is cleared and all pieces above it drop by one row. We prove that in the offline version of Tetris, it is NP-complete to maximize the number of cleared rows, maximize the number of tetrises (quadruples of rows simultaneously filled and cleared), minimize the maximum height of an occupied square, or maximize the number of pieces placed before the game ends. We furthermore show the extreme inapproximability of the first and last of these objectives to within a factor of p^(1-epsilon), when given a sequence of p pieces, and the inapproximability of the third objective to within a factor of (2 - epsilon), for any epsilon>0. Our results hold under several variations on the rules of Tetris, including different models of rotation, limitations on player agility, and restricted piece sets.Comment: 56 pages, 11 figure

Factorised steady states for multi-species mass transfer models

A general class of mass transport models with Q species of conserved mass is considered. The models are defined on a lattice with parallel discrete time update rules. For one-dimensional, totally asymmetric dynamics we derive necessary and sufficient conditions on the mass transfer dynamics under which the steady state factorises. We generalise the model to mass transfer on arbitrary lattices and present sufficient conditions for factorisation. In both cases, explicit results for random sequential update and continuous time limits are given.Comment: 11 page