• 한국연소학회지
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• 제11권1호
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• pp.19-26
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• 2006

Structure of edge flame established in a mixing layer, formed between two uniformly flowing pure $CH_4$ and pure $O_2$ streams, is numerically investigated by employing a detailed methane-oxidation mechanism. The numerical results exhibited the most outstanding distinction of using pure oxygen in the fuel-rich premixed-flame front, through which the carbon-containing compound is found to leak mainly in the form of CO instead of HC compounds, contrary to the rich $CH_4-air$ premixed flames in which $CH_4$ as well as $C_2H_m$ leakage can occur. Moreover, while passing through the rich premixed flame, a major route for CO production, in addition to the direct $CH_4$ decomposition, is found to be $C_2H_m$ compound formation followed by their decomposition into CO. Beyond the rich premixed flame front, CO is further oxidized into $CO_2$ in a broad diffusion-flame-like reaction zone located around moderately fuel-rich side of the stoichiometric mixture by the OH radical from the fuel-lean premixed-flame front. Since the secondary CO production through $C_2H_m$ decomposition has a relatively strong reaction intensity, an additional heat-release branch appears and the resulting heat-release profile can no longer be seen as a tribrachial structure.

• Asian-Australasian Journal of Animal Sciences
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• 제22권10호
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• pp.1420-1428
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• 2009

In this study we cloned and characterized a novel lipid-accumulating gene, the oxidized low-density lipoprotein receptor 1 (OLR1), which is associated with lipogenesis. We analyzed the gene structure and detected the mRNA transcriptional expression levels in pig adipose tissues at different months of age (MA) and in different economic types (lean type and obese type) using real-time fluorescence quantitative PCR. OLR1 expression profile in different tissues of pig was analyzed. Finally, we studied the correlation between OLR1 and lipid metabolism related genes including peroxisome proliferator-activated $receptor{\gamma}2$ ($PPAR{\gamma}2$), fatty acid synthetase (FAS), triacylglycerol hydrolase (TGH), CAAT/enhancer binding protein $\alpha$ ($C/EBP{\alpha}$) and sterol regulatory element binding protein-1c (SREBP-1c). Results indicated that the OLR1 gene of the pig exhibited the highest homology with the cattle (84%), and the lowest with the mouse (27%). The signal peptide located from amino acid 38 to 60 and the domain from amino acid 144 to 256 were shared by the C-type lectin family. The expression level of OLR1 in pig lung was exceedingly higher than other tested tissues (p<0.01). In pig adipose tissue, the expression level of OLR1 mRNA increased significantly with growth (p<0.01). The expression level of OLR1 mRNA in obese-type pigs was significantly higher than that of lean-type pigs of the same monthly age (p<0.05). In adipose tissue, the expression of OLR1 correlated with $PPAR{\gamma}2$, FAS and SREBP-1c, but not TGH or C/EBP${\alpha}$. In conclusion, OLR1 was highly associated with fat deposition and its transcription, as suggested by high correlations, was possibly regulated by $PPAR{\gamma}2$ and SREBP-1c.

• 한국도로학회논문집
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• 제7권1호
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• pp.21-29
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• 2005

건설폐기물의 재활용방법 중 하나는 폐콘크리트 재생골재를 도로포장재료로 활용하는 것이다. 하지만 재생골재에 대한 많은 연구와 기술개발에도 불구하고 생산공정에 포함된 이물질 때문에 실제 도로포장재료로의 적용은 미비한 실정이다. 본 연구에서는 재생골재내에 포함된 이물질의 특성에 따라 무기이물질과 유기이물질로 구분하였으며 , 각 이물질이 포장 공용성에 미치는 영향을 제시하였다. 또한 재생골재내에 포함된 무기이물질 함유량과 압축강도와의 관계, 유기이물질 함유량과 수정 CBR과의 상관관계를 통하여 도로포장층인 린콘크리트 기층과 보조기층에 적용 가능한 이물질 함량기준을 제시하였다. 린콘크리트 기층에는 무기이물질 함유량 질량비 10% 이하, 입상재료 보조기층에는 유기이물질 함유량 부피비 2% 이하일 때 재생골재를 포장에 적용 가능한 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제20권10호
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• pp.1485-1489
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• 2007

Achaete-scute like 2 (ASCL2) gene encodes a member of the basic helix-loop-helix transcription factor which is essential for the maintenance of proliferating trophoblasts during placental development. ASCL2 gene preferentially expresses the maternal allele in the mouse. However, it escapes genomic imprinting in the human. In this study, the complete open reading frame consisting of 193 amino acids of ASCL2 gene was obtained. Sequence analysis indicated that a C-G mutation existed in the 3' region between Meishan and Large White pigs. The polymorphism was used to determine the monoallelic or biallelic expression with RT-PCR-RFLP in pigs of Large $White{\times}Meishan$ $F_1$ hybrids. Imprinting analysis indicated that the ASCL2 gene expression was biallelic in all the tested tissues (heart, liver, spleen, lung, kidney, stomach, small intestine, skeletal muscle, fat, uterus, ovary and pituitary). PCR-RFLP was used to detect the polymorphism in 270 pigs of the "$Large\;White{\times}Meishan$" $F_2$ resource population. The statistical results showed highly significant associations of the genotypes and fat meat percentage (FMP), lean meat percentage (LMP) and ratio of lean to fat (RLF) (p<0.01), and significant associations of the genotypes and loin eye area (LEA) and internal fat rate (IFR) (p<0.05).

• Asian-Australasian Journal of Animal Sciences
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• 제12권8호
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• pp.1171-1176
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• 1999

The precision and reliability of the Computer Image Analysis technique using a desk top computer for extracting information from carcass cross section scans was evaluated by the repeatability (R) and coefficient of variation (CV) for error variance. The 6th and 7th ribs cross section of carcasses from 55 fattened Japanese Black steers were used. The image analysis was conducted using a desk top computer (Macintosh-Apple Vision 1710 Display) connected to a scanner and an image capture camera. Two software applications, Adobe Photoshop and Mac Scope were used interchangeably. The information extracted and measured were individual muscle area, circumference length, long and short axes lengths, muscle direction; distance between any two muscle centers of gravity; cross section total area, lean, fat, and bone. The information was extracted after the processes of scanning, digitization, masking, muscle separation, and binarization. When using the Computer Image Analysis technique by desk top computer, proper digitization and selection of scanning resolution are very important in order to obtain accurate information. The R-values for muscle area, circumference, long and axes lengths, and direction ranged from 0.95 to 0.99, whereas those of the distance between any two muscle centers of gravity ranged from 0.96 to 0.99, respectively. For the cross section total area, lean, fat, and bone it ranged from 0.83 to 0.99. Excellent repeatability measurements were observed for muscle direction and distance between any two muscle centers of gravity. The results indicate that the Computer Image Analysis technique using a desk top computer for extracting information from carcass cross section is reliable and has high precision.

• Asian-Australasian Journal of Animal Sciences
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• 제15권10호
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• pp.1391-1394
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• 2002

The polymorphism of insulin-like growth factor-I (IGF-I) in 13 pig breeds (total n=559) was detected by PCR-Hha I- RFLP, and allele A (151 bp and 28 bp) or allele B (116 bp, 35 bp and 28 bp) were observed. In these pig breeds, it was found that European pig breeds carried high frequencies of allele B, while Chinese native pig breeds carried high frequencies of allele A. Meanwhile the role of porcine IGF-I was investigated in 117 Nanchang White pigs and 360 Large Yorkshire pigs. Eight traits about growth and carcass were recorded for analyzing the associations between IGF-I gene polymorphism and performance quantitative traits. In the Nanchang White pigs, those with AA genotype generally had higher birth weight than those with AB genotype (p<0.05), but all these genotypes had no significant effect on the other traits which had been analyzed. In Large Yorkshire pigs, those with BB genotype had higher 2 months and 6 months body weight than those with AA genotype (p<0.05), and had a thicker hind-back-fat thickness and mid-back-thickness than those with AB and BB genotypes (p<0.05). And those with BB genotype were the thinnest in Large Yorkshire. Furthermore, pigs with AA genotype had a lower lean percentage than those with AB and BB genotypes (p<0.01), and the lean percentage of those with BB genotype was the highest. Based on these results, it is possible to make the IGF-I gene locus into the application of marker-assisted selection programmes.

• Asian-Australasian Journal of Animal Sciences
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• 제8권6호
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• pp.617-625
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• 1995

Distribution of wholesale carcass cuts and tissues was studied in Omani Dhofari bulls and steers raised under intensive management and slaughtered over a range of 110 to 210 kg body weight. The fore quarter of Dhofari cattle carcasses was heavier than the hind quarter with the chuck being the heaviest cut in the half carcass followed by the round whereas the flank was the lightest cut. Proportions of the fore quarter and its cuts increased whereas that of the hind quarter and its cuts decreased with increasing carcass weight. The fore quarter contained higher proportions of carcass tissues especially intermuscular fat than the hind quarter. The chuck and round contained the highest proportions of lean and bone and the flank the least. There was a general trend of increasing proportions of fat and decreasing proportions of lean and bone in carcass cuts and fore and hind quarters with increasing slaughter weight and age. As % total body fat (TBF), total carcass fat (TCF) increased whereas total non-carcass fat (TNCF) decreased. The largest proportion of TBF was deposited in the intermuscular site. Among the TNCF depots, the kidney and omental contributed the highest proportions whereas the pelvic and channel were the lowest. Proportions of M. rhomboideus and M. splenius increased in the half carcass whereas that of M. semitendinosus decreased as the cattle increased in size. The axial skeleton contributed 47.4-51.1, the fore limb 21.6-22.6 and the hind limb 23.9-26.2% of the total carcass bone. Proportions of axial skeleton increased whereas that of fore and hind limbs decreased with increasing slaughter weight and age. There were no major effects of castration on the distribution of weight of carcass cuts or carcass tissues. Steers had higher total body fat at 160 kg body weight and higher proportions of mesenteric, scrotal, pelvic, kidney and total non-carcass fat at 210 kg weight than bulls. As % of total body fat, steers fad significantly higher kidney and total non-carcass fat. There was little effects of castration on proportions of dimensions of individual muscles or bones.

• Asian-Australasian Journal of Animal Sciences
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• 제17권5호
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• pp.693-699
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• 2004

Live animal selection programs that favor animals with a minimum amount of carcass fat are used for improving breeding flocks of sheep. To predict carcass characteristics of live sheep using body measurements in breeding flocks, 200 male and female lambs of two fat-tailed Iranian sheep breeds (Moghani and Makui) were used. Depth of soft tissue over the 12th rib of the live animals was measured with ultrasound (ULGR) and with hypodermic needle (NGR). The height at withers (HW), body length (BL), circumference of heart girth (CH) and width of hooks (WH), were measured. All animals were slaughtered; carcasses were cut into joints and dissected. Breed had a significant effect on all of the live easurements. The Moghani breed showed a higher value for HW, CH, ULGR and NGR, compared to that of Makui. Except for soft tissue depths; ULGR, NGR and GR, the male lambs showed higher values in live and carcass measurements than females. Percentages of carcass, total fat and intermuscular fat in females were higher than that of male lambs. In spite of the higher amount of subcutaneous and intermuscular fat in female (which is usually used for their physiological need, such as pregnancy and lactation), the male lambs had a heavier fat-tail than females. There was a wide range of variation of percentage of total carcass fat and total chemical fat content of carcass in the two breeds. Eventually this wide variation could be use by animal breeders for selection of animals with a lesser amount of carcass fat. Live weight of lambs showed a relatively low correlation with percentage of carcass lean, total fat and subcutaneous and intermuscular fat. Total lean meat was predicted with relatively high coefficients of determination in the two breeds ($R^2$=0.61 and 0.89, respectively). Live weight and carcass traits were predicted using simple measurements, but with $R^2$ ranging from 0.53 to 0.93.

• Asian-Australasian Journal of Animal Sciences
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• 제14권10호
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• pp.1434-1439
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• 2001

Eighty crossbred pigs (Large White x Landrace) weighing 9.9 kg were assigned on the basis of sex, weight and Jitter to one of five dietary treatments in a factorial $(5\;treatments\;{\times}2\;sexes)$ arrangement to compare the nutritive value of hulled and dehulled peas fed with or without enzyme (0.25% Allzyme PF and 0.5% Biogal-S). A barley and soybean meal diet served as a control. Eight castrates and eight gilts were fed each diet. Digestibility coefficients for dry matter, crude protein and energy were higher for diets containing dehulled peas than hulled peas. In addition, enzyme supplementation modestly increased the digestibility of all three nutrients. Over the entire experimental period (9.9 to 103.3 kg), there were no performance differences (p>0.05) between pigs fed soybean meal based diets or diets based on any of the pea products. In addition, there were no differences in performance between pigs fed diets containing hulled or dehulled peas or between pigs fed diets with or without dietary enzyme. Castrates gained weight significantly faster, consumed more feed but had a poorer feed conversion than gilts (p<0.05). There were no differences in carcass traits between pigs fed diets based on soybean meal or any of the pea products. Carcass traits were similar for pigs fed hulled or dehulled peas while enzyme supplementation also had no effect on carcass data. Castrate pigs had a lower carcass value index, estimated lean yield and loin lean depth (p<0.05). Loin fat depth was greater for castrates than gilts (p<0.05). The overall results of this experiment provide little support for the need for enzyme supplementation of pea based diets fed to swine. In addition, dehulling did not appreciably improve the nutritive value of peas. Therefore, since the process adds to the cost of the raw product, its use is unlikely to be economical.

• Asian-Australasian Journal of Animal Sciences
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• 제14권11호
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• pp.1592-1597
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• 2001

Sixteen pigs from 2 distinct genetic lines (LGAH and VFIL) obtained after eight generations of divergent selection for high (H) and low (L) lean tissue growth rate with ad-libitum feeding (LGA) and voluntary feed intake (VF1), respectively, were used in this study. The objectives of this investigation were to establish appropriate working conditions for the postheparin plasma lipoprotein lipase (LPL) assay and to study relationships between fat deposition and plasma lipids, very low density lipoprotein (VLDL) lipids, VLDL-subfractions and postheparin plasma LPL activity in growing pigs. Four preliminary experiments were performed to determine the appropriate working conditions for the postheparin plasma LPL assays. Postheparin plasma preincubated with SDS (20-50 mM) at $26^{\circ}C$ for 45 minutes inhibited hepatic lipase activity. A total of $2{\mu}l$ VLDL/assay produced maximum stimulation of LPL activity. Postheparin plasma protein and increasing incubation time contributed an optimum response. LGAH pigs had a significantly higher proportion subtraction 2 than VFIL pigs. No differences were observed in postheparin plasma LPL activity and backfat thickness for two lines of pigs. There were positive correlations between backfat thickness and proportion of subtractions 2 and postheparin plasma LPL activity but the results were not statistically significant. Backfat thickness was not statistically correlated with proportion of subtraction 2 and postheparin plasma LPL activity in a multiple regression analysis. It is believed that the apolipoprotein E, which is present in higher quantities in VLDL-subfraction 2 plays an important role for clearing VLDL triacylglycerol into adipose tissue. LPL activity of pigs can be measured by using postheparin plasma technique. If the relationships of backfat thickness and VLDL-subfraction 2 and postheparin plasma LPL activity can be established, it suggests that these parameters could be used as indicators in selection programmes. Further experiments need to be conducted by using larger sample size and different breed of pigs with greater differences in backfat thicknesses to confirm these trends.