• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.326-326
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• 2012

ZnS를 합성하는 방법 중 thioacetamide (TAA)를 녹인 물에 ZnO template를 넣어서 황화시키는 방법이 있다. 이 방법은 실험과정이 간편할 뿐만 아니라 그 반응양의 조절도 용이해 ZnS-ZnO core-shell 구조나 ZnS hollow 구조 등을 만드는데 널리 사용되고 있다. 그러나 다양한 형태의 ZnS 구조체 합성에 관한 연구는 활발한 반면, ZnS의 상형성 과정이나 구조 변화와 같은 ZnO의 황화 과정 기구에 관한 연구는 매우 미비한 실정이다. ZnS는 기본적으로 저온에서는 cubic sphalerite 구조를, 고온에서는 hexagonal wurtzite 구조를 안정상으로 가진다. 또한, 8H나 15R 등과 같은 다양한 polytype 구조도 존재한다. 그러나 다양한 구조에서 비슷한 면간거리가 존재하기 때문에 결정구조의 분석이 어려운 실정이다. 이러한 비슷한 면간거리를 가지는 ZnS 등의 결정구조 분석에 있어 원자배열을 직접적으로 관찰할 수 있는 투과전자현미경 (TEM, transmission electron microscopye)을 이용한 연구는 큰 강점을 가진다. 본 연구에서는 다공성 ZnO 막을 황화시켜 형성된 ZnS 막의 미세구조 특성을 분석하였다. 다공성 ZnO 막은 패턴된 Si (111) 기판 위에 스핀코팅법을 이용하여 4,000 rpm의 속도로 증착되었으며 ZnO 결정화를 위해 150 도와 500도에서 각각 drying과 후열처리를 수행하였다. 이렇게 만들어진 ZnO 막을 TAA를 녹인 물에 넣어 48 시간 동안 반응시켰고 최종적으로 ZnS 막을 생성하였다. 다공성 ZnS 막의 미세구조를 분석하기 위해 주사전자현미경 (SEM, scanning electron microscope), X-선 회절분석기 (XRD, x-ray diffractometer), 그리고 투과전자현미경을 이용하였으며, 정확한 결정구조 분석을 위하여 결정구조 시뮬레이션을 병행하였다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.2
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• pp.248-251
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• 2000

To investigate the effects of packaging films (functional MA films/FC30, FC50, MA film/0.03 mm LDPE, corrugated paperboard box/control) weight loss, firmness, total ascorbic acid, chlorophill and overall appearence were evaluated. Weight loss of cucumbers packed with FC30 and FC50 at 2$0^{\circ}C$ after 7 days were 1.0 and 0.6%, that of the control was 2.9%, those of LDPE was 0.5%. The firmness of FC30 and FC50 at 2 $0^{\circ}C$ after 7 days were 1.0 and 0.6%, that of the control was 2.9%, those of LDPE was 0.5%. The firmness of FC30-, FC50 and LD was higher than that of the control. Total ascorbic acid contents (TAA) of cucumbers packed with control, LD, FC30 and FC50 box were 9.96, 10.86, 11.37 and 11.29 mg% after 7 days. TAA of FC box was 10% higher than that of the control. Chlorophill content of FC boxes wase 16% higher than of the control. Overall appearence of cucumber packed with FC boxes was better than that of the control.

• Korean Journal of Veterinary Service
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• v.18 no.1
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• pp.1-21
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• 1995

To elucidate pathogenesis of bovine leukemia virus(BLV) in Korean native goats, the goats experimentally infected with BLV were studied especially for the aspects of infectivity and hematological changes. The experimental goats were examined for 27 months by agar-gel immunodiffusion(AGID) test and syncytium formation assay. During this period, changes of total leucocyte, absolute Iymphocyte and atypical Iymphocyte were examined, and the distribution of surface immunoglobulin ( sIg ) -bearing cells and rosette forming cell (RFC) in the peripheral Iymphocyte were also investigated. By indirect immunofluorescence (IFA) and complement dependent antibody cytotoxicity (CDAC) assay using monoclonal antibody(Mab) against bovine leukosis tumor-associated anti-gen(BL-TAA), changes of BL-TAA positive Iymphocyte in peripheral blood were measured. The results obtained through the experiment were summarized as follows. 1. Antibody titers were measured by AGID using gP51 and P24 antigens. The animals were serologically converted at 2 months post-inoculation(pi) in gP51 antigen, whereas sero-converted at 4 months pi in P24 antigen. In comparison with antibody titers for gP51, P24 antigen showed lower titers throughout the trial period. 2. The peripheral lymphocytes from all of the infected goats, as co-cultivated with F8l cells manifested syncytial formation at 4 months pi. 3. On counting total leucocyte, Iymphocyte and atypical Iymphocyte, two out of four infected goats showed normal distribution, while No 2 of the remaining two revealed temporal and No 3, Persistant increasing number of the cells. 4. The optimal condition of rosette formation of the peripheral Iymphocyte of normal Korean native goats was shown in the sheep erythrocyte treated with 0.1M AET for 30 nun at $37^{\circ}C$. When the Iymphocytes were treated in nylon wool column, the number of sIg-bear-ing cell were increased in the nylon wool adherent cells, but RFC was increased in the non-adherent cells. Of the infected goats, No 2 and No 3 showed significantly increasing number of sIg-bearing cells at 18 months pi. 5. The Iymphocytes of No 2 and No 3 goats reacted positively in IFA using Mab against BL-TAA at 12 months pi and 18 months pi, respectively. In CDAC test, all of four infected goats revealed positive reaction at 24 months pi. The higher positive rates were observed in No 2 and No 3 as compared with the remainders.

• Tribology and Lubricants
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• v.17 no.1
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• pp.1-9
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• 2001

Hard disk drives operate in various environmental conditions. Thus, it is necessary to assess the reliability of the head/disk interface under these conditions. In this work, stiction and acoustic emission signals were investigated under different temperature, humidity, and ambient pressure conditions. Also, track average amplitude was observed for disk failure in N$_2$environment. It is shown that failure of the head/disk interface occurs more readily at high temperature and low ambient pressure conditions.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.7
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• pp.1003-1007
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• 2001

This experiment was conducted to investigate the effects of dietary SAA (sulfur-containing amino acids) on growth performance, nutrient digestibility and blood urea nitrogen (BUN) content, and to determine the optimal SAA:lysine ratio for growing barrows and gilts. A total of 150 pigs (75 barrows and 75 gilts, Landrace${\times}$Yorkshire${\times}$Duroc) were assigned to 6 treatments with 5 replicates of 5 pigs per pen. All pigs were fed diets containing either 1.12 (for barrows) or 1.33% (for gilts) dietary lysine with increasing SAA levels (50, 55 and 60% of dietary lysine) in a $2{\times}3$ factorial design. Throughout the whole experimental period (15 to 54 kg body weight), there was no interaction between sexes and SAA:lysine ratios on ADG, ADFI and FCR. However, increasing the SAA:lysine ratio from 50 to 60% in a diet showed a trend to increase ADG and ADFI of barrows. None of differences in nutrient digestibilities except for calcium and phosphorus were observed and gilts showed higher digestibility of calcium and phosphorus (p<0.05). Among dietary SAA:lysine ratios, there were no differences in apparent nutrient digestibility. Mean values of the essential amino acids (EAA), non-essential amino acids (NEAA) and total amino acids (TAA) digestibilities were higher in gilts than barrows (p<0.01). However, no differences in mean value of EAA, NEAA and TAA digestibilities were observed among dietary SAA:lysine ratios. Between sexes and among SAA:lysine ratios, no significant difference in BUN concentration was observed. This study demonstrated that the optimal inclusion ratio of SAA:lysine was 55% and below 50% in barrows and gilts, respectively.

• Korean Journal of Poultry Science
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• v.40 no.2
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• pp.129-138
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• 2013

An experiment was conducted to determine the effects of origins of soybean meal (SBM) on growth performance, nutrients and energy retention and fecal microflora in broilers. The SBM originating from Korea, Brazil and India were used. A total of 480 broiler chicks (average initial BW, 41.8 g) were randomly allotted to 6 treatments. Each treatment had 4 replicate pens with 20 chicks per pen. Birds were fed diets containing SBM originated from Korea (domestic SBM), Brazil or India (imported SBM) and the diets were based on the total amino acid (TAA) or true digestible amino acid (TDAA). Experimental diets were fed in two phases, starter (d 0~21) and finisher (d 22~35). The overall weight gain, feed intake and FCR were better (P<0.05) in birds fed Korean SBM. During starter and finisher periods, birds fed diets containing Korean SBM had greater (P<0.05) retention of GE, DM, and CP (P<0.05) as compared with Birds fed diets containing SBM from India. In addition, diets formulated on TDAA basis had grater (P<0.05) CP retention during starter period and DM, GE and CP retention during finisher period. There were no differences (P>0.05) in the excreta microflora and overall feed cost per kg body weight gain in birds fed SBM from different origins; however, diets formulated on TDAA basis had lesser (P<0.05) feed cost per kg body weight gain in birds when compared with diets formulated on TAA basis. These results indicate that Korean SBM has better nutrients digestibility than SMB originated from Brazil and India, which contributes to the improved performance of broilers. In addition, better performance was obtained when diets were formulated on TIDAA basis.

• Korean Journal of Environmental Agriculture
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• v.35 no.2
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• pp.104-110
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• 2016

BACKGROUND: There is lack of comprehensive compositional data of the amino acid profile of spinach with regard to different cultivars. A more detailed knowledge in this aspect will be of benefit in the future selection of spinach genotypes with improved nutritional quality.METHODS AND RESULTS: The effects of cultivar type (Jeoncheonhu, Sagyejul, Namdongcho and Mustang) and harvest time (79^th, 116^th and 145^th days after sowing or DAS) on the concentrations of free amino acids in field-grown spinach (Spinacia oleracea) were examined. About 35 different free amino acids were detected and quantified by the amino acid analyzer. Glutamic acid and proline were identified as the major amino acids, while α -aminoadipic acid and α-aminobutyric acid were present in much lower concentrations. Spinach constituted 1468.4 mg/100 g total free amino acids (TAA), of which essential amino acids, neutral/acidic amino acids and sulphur containing amino acids constituted around 15, 45 and 2% of the TAA, respectively. The most limiting amino acids among the leafy vegetables - cysteine was recorded only in Mustang harvested at 116 DAS. Free amino acid contents did not differ significantly among the spinach cultivars and also at different harvest times.CONCLUSION: The data show that, either of the spinach cultivars, preferably Mustang harvested on or after 116 DAS can serve as a significant source of nutritionally relevant amino acids to meet the demand of the growing populations.

• Biomedical Science Letters
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• v.2 no.2
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• pp.231-240
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• 1996

Human blood clotting (coagulation) factor 9 cDNA which codes for 461 amino acid has been cloned by screening human fetal liver cDNA library using PCR. This 1.4 kb cDNA spanning from the ATG initiation codon to the TAA termination codon was cloned into bacterial .expression vector pGEX-2T, generating pGEX-F9 plasmid. The plasmid pGEX-F9 expresses about 73 kDa GST (Glutathione S-transferase)-Factor 9 fusion protein when introduced into E. coli. Western blot analysis using polyclonal antibody raised against human factor 9 confirmed this fusion protein contains factor 9 protein. The level of GST-factor 9 expression was about 20% of total protein and the purification of fusion protein was efficiently achieved by using GST agarose bead based on one step purification protocol.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.6
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• pp.855-860
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• 2005

This study was designed to test the effects of changes in energy and protein intake levels on the maternal milk amino acid concentrations over the short-term in lactating mares. Three lactating mares were enrolled for the study 7 weeks after parturition. A low-energy and low-protein diet (LEP) was administered during the first week of the study, followed by administration of a high-energy and high-protein diet (HEP), again for a week (day 1 to day 7), and milk was sampled thrice daily at intervals of 8 h during the study period. The mean amino acid concentrations in the maternal milk, except for those of proline, serine and valine, were significantly higher in the HEP feeding period than during the LEP feeding period (p<0.05). The sum of the concentrations of all the amino acids (TAA) in the maternal milk samples during the HEP and LEP feeding periods was 1,644.9${\pm}$26.9 and 1,542.3${\pm}$36.0 mg/100 g, respectively, the difference between the two was not significant. When the ratio of each amino acid concentration to the TAA in the maternal milk was analyzed, there were significant differences between the HEP and LEP feeding periods for all amino acids, except glycine, serine, alanine and histidine. It was found that the concentrations of glutamic acid+glutamine, serine, threonine, arginine and valine were significantly higher (p<0.05) on day 1 than on day 7 during the LEP feeding period, and there were no such differences during the HEP feeding period. In regard to the effects of changes in the energy and protein intake levels in lactating mares, no changes in milk amino acid concentrations were found following administration of HEP for a week, whereas 7 days of administration of LEP was associated with a decrease in the amino acid concentrations.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.3
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• pp.165-175
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• 1990

This experiment was conducted to examine the effects of different carbohydrate and nitrogen source upon the utilization of amino acids in the small intestine of sheep. The results obtained are as follows: 1) For the quantities of total amino acid-N(TAA-N), essential amino acid-N(EAA-N) and nonessential amino acid-N(NEAA-N) passing at the duodenum and ileum except NEAA-N passing at the ileum were no significant differences (p>0.05) between diets. The quantities of NEAA-N passing at the ileum for the diets containing meat and bone meal were significantly higher (p>0.05) than the diets containing soybean meal. The mean values for the proportionate disappearance apparently digested TAA-N, EAA-N and NEAA-N within the small intestine for four diets were $0.692{\pm}0.0449$, $0.702{\pm}0.0132$ and $0.682{\pm}0.726$, respectively. 2) There were no significant differences (p>0.05) in duodenal individual amino acid flow between diets with the exception of aspartic acid and glycine. The amounts of each amino acid in duodenal digesta, expressed as a proportion of the amounts ingested for the four diets, were shown that there were net gains of EAA with the exception of arginine and NEAA with the exception of glutamic acid, glycine and praline prior to the small intestine. 3) Within the small intestine, there were no significant losses of each EAA (p>0.05) but significant losses of aspartic acid and glycine of NEAA between diets (p<0.01). The mean values of the proportionate losses of methionine, alanine and lysine within the small intestine were $0.816{\pm}0.04$, $0.767{\pm}0.04$ and $0.732{\pm}0.01$, respectively.