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The purpose of this study was to assess the genetic variation and establish the relationship amongst breeds and strains using 7 chicken specific microsatellite markers. A total of 317 DNA samples from four Korean native chicken (KNC) strains (KR: Korean Native Red chicken strain, KY: Korean Native Yellow chicken strain, KL: Korean Native Black chicken strain, KO: Ogol chicken strain) and three introduced endemic chicken breeds (LE: Leghorn chicken breed, RI: Rhode Island Red chicken breed, CO: Cornish chicken breed). The size of microsatellite markers was decided using GeneMapper Software (v.4.0) after being analyzed using an ABI 3130 Genetic Analyzer. Frequencies of microsatellites markers were used to estimate heterozygosities and genetic distances. The lowest distance (0.074) was observed between the KY and KL breeds and the highest distance (0.779) between the KL and LE breeds. The KNC strains (KR, KY, KL) have comparatively near genetic distance each other. On the other side, each individual was not ramified to different groups and were spread evenly in phylogenetic dendrogram about all the KNC of each strain populations. But the endemic breed populations (LE, RI, CO) were ramified to different groups. The microsatellite polymorphism data were shown to be useful for assessing the genetic relationship between Korean native strains and other foreign breeds.

A total of 17 polymorphic microsatellite markers on chromosome 1 were used for allelic association tests with phenotypic traits in Korean native chicken. Chi-square tests were performed to compare the frequencies of individual alleles between the high and the low trait groups. The frequency of allele 123 of MCW0160 showed a significant difference between the high and the low groups in the trait of egg weight (EW). Three markers, namely ADL0234, UMA1.125 and ADL0101, were found to show significant differences in allelic distribution for the trait of the first lay day (FLD). UMA1.117, ADL0020, UMA 1.019, LMA1 and ADL0238 were found to show significant differences in allelic distribution for the trait of body weight (BW). ADL0101 and ADL0238 were found to show significant differences in allelic distribution for the trait of number of egg production(EP). In this study, we identified the QTL for economic traits at around 94 (MCW0160), 151 (ADL0234), 170 (UMA1.125), 225 (UMA1.117), 285 (ADL0020), 387 (UMA1.019), 418 (LMA1), 500 (ADL0101) and 520 (ADL0238) cM on chromosome 1 in Korean native chicken. The results provided a useful guideline for identification of positional candidate gene and marker-assisted selection for economic traits in Korean native chicken.

Nine brand populations of Hanwoo cattle were characterized using 11 microsatellite DNA markers. The studied populations were: Ansung, Yangpyang, DaeGwanryeng, Palkongsangkangwoo, Hoengseong, Jangsu, Sumjinkang, Hadong, Nam-hae. The observed heterozygosity, expected heterozygosity, and polymorphism information content were calculated. Allele frequencies were calculated and used for the characterization of each brand population and to study their genetic relationships. Genetic distances were estimated using Nei`s DA genetic distance and the resultant DA matrix was used in the construction of phylogenetic trees. The NJ tree showed that Ansung and Yangpyang, Sumjinkang and Jangsu, Namhae and Ha-Dong are closely related and are considered to have undergone genetic exchange within the same locale. This study will contribute to the local Hanwoo brand industry.

The Function of the calcium sensing receptor (CaSR) is to control calcium levels by altering PTH (parathyroid hormone) secretion and renal calcium resorption. The influence of calcium on the basal and stimulated release of several hormones from chicken pituitary glands has been determined in vitro. The objective of this study was to identify SNP in chicken CaSR gene and to investigate the effect of the SNP on economic traits. The sequencing analysis method was used to identify nucleotide polymorphisms within chicken CaSR gene. This study identified SNP at position 1949 bp(Genebank accession No : XM_416491) in the exon 1. The SNP changed the amino acid to alanine(GCC) from serine(TCC). This SNP showed three genotypes, AA, AS and SS by digestion with the restriction enzyme NcoⅠ using the PCR-RFLP method. The A963S showed significant effect only on the first lay day (P

This study was conducted to analyze the genetic characteristics of Korean Native Pigs(KNP), and to establish an individual identification system comprising many microsatellite markers located on different pig autosomes. Genotype data from 13 microsatellites typed in 446 animals was used to determine the validation of a method of individual identification in 4 KNP. A total of 112 alleles of the 13 microsatellites were detected and average heterozygosities(polymorphic information content) ranged from 0.286(0.423) to 0.686(0.796) in this study. Comparing the pattern of allele frequency among the KNP, Yorkshire, Landrace and Duroc breeds, there was specific differentiation between populations at multi-allelic loci. The cumulative power of discrimination(CPD) was 99.999% by including 10 microsatellite loci for the individual identification system. The probability that two different individuals incidentally have same genotype was estimated to be . The system employing these 10 markers therefore proved to be applicable to the individual identification of KNP.

Phospholipid transfer protein (PLTP) regulates high-density lipoprotein metabolism. The gene encoding PLTP is located on bovine chromosome 13. The objective of this study was to identify single nucleotide polymorphisms (SNPs) in the Hanwoo (Bos taurus coreanae) PLTP gene to detect novel mutations affecting economically important traits. Five SNPs were identified in the coding region (C7368T, G7453A, C9888T, and C9905T) and intron (A1750G). G7453A changes amino acid 362 of PLTP from alanine to threonine, and C9888T changes amino acid 491 of PLTP from proline to serine. Statistical analyses revealed that the G7453A and C9888T polymorphisms in the PLTP gene were significantly associated with marbling score (P < 0.05). The relationship between haplotype and economic traits was analyzed and found to be significantly associated with marbling score (P < 0.05). The results suggest that PLTP polymorphisms might be an important genetic influence on economic traits in Hanwoo.

Friction is often a nuisance, but it can be useful too. Brakes, clutches, and tires rely on it, of course, though the inevitable fractional heat remains a problem. Other applications use frictional heat: friction cutting and welding, skiing, skating, and curling. The damage to magnetic disks caused by head-disk contact and the striking of matches are also examples.This article illustrates a framework where the thermal aspects of friction can be analyzed in an informative way. It uses a unified approach to the calculation of flash and bulk heating, and a helpful diagram—the frictional temperature map—to display the results. The method is approximate, but the approximations have been carefully chosen and calibrated to give precision adequate to most tasks, and the gain in simplicity is great.The symbols used in this article are defined in Table I.When two contacting solids 1 and 2, pressed together by a normal forceF, slide at a relative velocity ν and with coefficient of friction ü, heat is generated at the surface where they meet. The heat generated,q, per unit of nominal contact area,An, per second isThe heat flows into the two solids, partitioned between them in a way that depends on their geometry and thermal properties. Figure 1 shows one geometry commonly used for laboratory tests: the pin-on-disk configuration. The pin is identified by the subscript 1, the disk by subscript 2. Solid 1 can have properties which differ from those of solid 2.

Flow modulation epitaxy (FME) has been employed previously to synthesize III-V arsenides and phosphides. However, the ability of FME to extend growth to lower temperatures than those required for conventional organometallic vapor phase epitaxy (OMVPE) has only recently been explored for the synthesis of nitride based semiconductors. Because, in part, of the importance of low temperature growth to the synthesis of indium-containing group III-nitrides, this growth technique should be explored further. In this paper we report on the FME of group III-nitride compounds on sapphire and silicon carbide substrates.

Various condition monitoring techniques were applied during a laboratory engine test in order to understand the wear processes occurring and to determine a suitable method which could be applicable to the detection and diagnosis of abnormal engine conditions in practice. Fuel consumption rates were measured in conjunction with chemical analysis of the used oil by Fourier Transform Infrared Spectroscopy, and the various contaminant inspection methods. For the contaminant inspection of the wear debris in the lubricating oil, the quantitative and qualitative techniques of the Rotary Particle Depositor (RPD), Particle Quantifier (PQ), Spectrometric Oil Analysis, and Image Analyser Systems were applied and the results compared. The effectiveness of each to be able to respond to wear failure was also compared. Evaluation showed that, of the methods examined, the combination of RPD and PQ was the most suitable technique for the detection of abnormal wear occurring in the engine combustion zone. It is, therefore, suggested that this combination can be directly applied to internal combustion engines as an effective condition monitoring method.