Association of the thyroid hormone responsive spot 14 alpha gene with growth-related traits in Korean native chicken

Objective: Thyroid hormone responsive spot 14 alpha (THRSP) has been used to investigate the regulation of de novo lipogenesis because the variation of THRSP mRNA content in the tissue affects directly the ability of that tissue to synthetize lipids. Also, this gene responds to thyroid hormone stimulation and high level of carbohydrate feeding or insulin-injection. This study was carried out to investigate variations within THRSP and their effects on body and carcass weights in Korean native chicken (KNC).Methods: A total of 585 chickens which represent the five lines of KNC (Black, Gray-Brown, Red-Brown, White, and Yellow-Brown) were reared and body weight data were recorded every two weeks from hatch until 20 weeks of age. Polymerase chain reaction- restriction fragment length polymorphism, DNA chips for Agilent 2100 Bioanalyzer, and Fluidigm Genotyping Technology, were applied to genotype selected markers. A linear mixed-effect model was used to access association between these single nucleotide polymorphism (SNP) markers and growth-related traits.Results: A total of 30 polymorphisms were investigated in THRSP. Of these, nine SNPs for loci were selected to perform association analyses. Significant associations were detected between g.-49G>T SNP with body weight at 20 weeks of age (BW20), g.451T>C SNP with growth at 10 to 12 weeks of age (GR10-12), and g.1432A>C SNP with growth at 14 to 16 weeks trait (GR14-16) and body weight at 18 weeks of age (BW18). Moreover, diplotype of the THRSP gene significantly affected body weight at 12 weeks of age (BW12) and GR10-12 traits. Diplotype of ht1/ht2 was favorable for BW12 and GR10-12 traits.Conclusion: These results suggest that THRSP can be regarded as a candidate gene for growth traits in KNC.

Calculation of Modes of Arc Welding under the Flux of Double-Sided Butt Joints

This paper gives the analysis of energy costs for arc automatic welding under the flux of double-sided butt joint without edge preparation according to the thickness of welding sheets. The coefficients for a linear dependence of specific energy from plate thickness are obtained. From this, a calculation method of effective power, current and arc voltage is proposed according to the joint formation speed. To calculate a fusion area of a weld section, a model of a surficial normal-circular heat source with an average heat flow in a heating spot 14−16 kW/cm2is used. Acceptable convergence of target and experimental cross-section areas of a weld is achieved for an arc reverse polarity. Calculation method let take into account the influence of arc polarity on a fusion area of a base metal. Main efficiency factors of a double-sided welding are defined. Possible reasons of augmentation of fusion effectiveness of a base metal in comparison with the electrode metal are noted.