Genetic diversity and selective breeding of red common carps in China

China has a very rich genetic diversity in common carp (Cyprinus carpio) and the red common carp plays an important role in Chinese aquaculture and genetic studies. Selective breeding, particularly crossbreeding has been applied successfully to red common carps in China, and the products of these efforts have been in commercial use since the 1970s. However, knowledge of the quantitative and molecular genetics of these carps is limited. Studies were therefore undertaken to: (1) understand the genetic diversity and genetic relationship of red common carps in China; (2) understand the inheritance of color phenotype of Oujiang color carp; (3) select stable Oujiang color carp with fast growth rate and ornamental Oujiang color carp comparable with the Koi common carp from Japan; (4) study the culture performance and culture systems suitable for the Oujiang color carp in cages and paddies; (5) extend better quality fish and appropriate culture systems for small scale fish farmers in poor areas

Seismic Analysis of Prestressed Bridge Pier Based on Fiber Section

AbstractFiber model analysis method based on flexibility method is carried out to build analysis model for integral cast in-situ prestressed bridge piers, and the nonlinear time-history analysis is conducted with the low-peried cyclic loading. The hysteretic behavior of prestressed reinforced concrete pier and common reinforced concrete pier are compared and analyzed. The results showed that prestressed reinforced concrete pier has preferable re-centring capacity, smaller residual deformation and worse energy dissipation capacity. Along with the increase of distance from prestress location to section centroid, the tension degree of prestressed reinforcements and the reinforcement ratio come a decrease the residual deformation and energy dissipation capacity of pier

Формування субрегіонів як напрям підвищення конкурентоспроможності та інвестиційної активності території

Характерною особливістю регіону є виконання ним не тільки економічних, а й соціальних функцій. Саме тут криється принципова відмінність між різними ланками відтворювального процесу. Кінцева мета відтворювального процесу регіону – матеріальний добробут населення, покращення навколишнього середовища, створення нормальних умов для праці й відпочинку, можливостей духовного розвитку особи і т. п

Simplified amino acid alphabets based on deviation of conditional probability from random background

The primitive data for deducing the Miyazawa-Jernigan contact energy or BLOSUM score matrix consists of pair frequency counts. Each amino acid corresponds to a conditional probability distribution. Based on the deviation of such conditional probability from random background, a scheme for reduction of amino acid alphabet is proposed. It is observed that evident discrepancy exists between reduced alphabets obtained from raw data of the Miyazawa-Jernigan's and BLOSUM's residue pair counts. Taking homologous sequence database SCOP40 as a test set, we detect homology with the obtained coarse-grained substitution matrices. It is verified that the reduced alphabets obtained well preserve information contained in the original 20-letter alphabet.Comment: 9 pages,3figure

Low-Frequency Optical Conductivity in Inhomogeneous d-wave Superconductors

Motivated by the recent optical conductivity experiments on Bi_2Sr_2CaCu_2O_{8+delta} films, we examine the possible origin of low-frequency dissipation in the superconducting state. In the presence of spatial inhomogeneity of the local phase stiffness rho_s, it is shown that some spectral weight is removed from omega=0 to finite frequencies and contribute to dissipation. A case where both rho_s and the local normal fluid density are inhomogeneous is also considered. We find an enhanced dissipation at low frequency if the two variations are anti-correlated.Comment: To appear in Phys. Rev.

An approach to F-theory

We consider BPS configurations in theories with two timelike directions from the perspective of the supersymmetry algebra. We show that whereas a BPS state in a theory with one timelike variable must have positive energy, in a theory with two times any BPS state must have positive angular momentum in the timelike plane, in that $Z_{0\tilde{0}}>0$, where $0$ and $\tilde{0}$ are the two timelike directions. We consider some generic BPS solutions of theories with two timelike directions, and then specialise to the study of the (10,2) dimensional superalgebra for which the spinor operators generate 2-forms and 6-forms. We argue that the BPS configurations of this algebra relate to F-theory in the same way that the BPS configurations of the eleven dimensional supersymmetry algebra relate to M-theory. We show that the twelve dimensional theory is one of fundamental 3-branes and 7-branes, along with their dual partners. We then formulate the new intersection rules for these objects. Upon reduction of this system we find the algebraic description of the IIB-branes and the M-branes. Given these correspondences we may begin an algebraic study of F-theory.Comment: 20 pages, no figures, late

Generalized Buneman pruning for inferring the most parsimonious multi-state phylogeny

Accurate reconstruction of phylogenies remains a key challenge in evolutionary biology. Most biologically plausible formulations of the problem are formally NP-hard, with no known efficient solution. The standard in practice are fast heuristic methods that are empirically known to work very well in general, but can yield results arbitrarily far from optimal. Practical exact methods, which yield exponential worst-case running times but generally much better times in practice, provide an important alternative. We report progress in this direction by introducing a provably optimal method for the weighted multi-state maximum parsimony phylogeny problem. The method is based on generalizing the notion of the Buneman graph, a construction key to efficient exact methods for binary sequences, so as to apply to sequences with arbitrary finite numbers of states with arbitrary state transition weights. We implement an integer linear programming (ILP) method for the multi-state problem using this generalized Buneman graph and demonstrate that the resulting method is able to solve data sets that are intractable by prior exact methods in run times comparable with popular heuristics. Our work provides the first method for provably optimal maximum parsimony phylogeny inference that is practical for multi-state data sets of more than a few characters.Comment: 15 page

Predicted Infrared and Raman Spectra for Neutral Ti_8C_12 Isomers

Using a density-functional based algorithm, the full IR and Raman spectra are calculated for the neutral Ti_8C_12 cluster assuming geometries of Th, Td, D2d and C3v symmetry. The Th pentagonal dodecahedron is found to be dynamically unstable. The calculated properties of the relaxed structure having C3v symmetry are found to be in excellent agreement with experimental gas phase infrared results, ionization potential and electron affinity measurements. Consequently, the results presented may be used as a reference for further experimental characterization using vibrational spectroscopy.Comment: 6 pages, 5 figures. Physical Review A, 2002 (in press