• Journal of the Korean Applied Science and Technology
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• v.38 no.2
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• pp.476-487
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• 2021

To prepare acrylic resin coatings containing 70% of solids, we used n-butyl methacrylate(BMA), methyl methacrylate(MMA), 2-hydroxyethyl methacrylate(2-HEMA), and acetoacetoxyethyl acrylate(AAEA), caprolactone acrylate(CLA) as raw materials, the glass transition temperature(T_g) of acrylic copolymer was adjusted around 50 ℃. The viscosity and molecular weight of the acrylic resins was increased with increasing OH values. Di-tert-amyl peroxide was found to be the suitable initiator to get high-solids acrylic resins. The optimum reaction conditions found in the study are 5 wt% of initiator, 4 wt% of chain transfer agent, 4 hrs of dropping time, and 140 ℃ of reaction temperature. The structure of the synthesized resins were characterized by FT-IR and ¹H-NMR spectroscopy. Number average molecular weight of 1900~2600 and molecular wight distribution of 1.4~2.1 were obtained. Crosslinked acrylic urethane clear coatings were obtained by curing reaction between the synthesized acrylic resins and hexamethylene diisocyanate trimer(Desmodur N-3300), the equivalent ratio of NCO/OH was 1.2/1.0. The physical properties from the following studies were carried out: viscosity(Zahn cup #2), adhesion, drying time, pot-life, pensil hardness, and 60° specular gloss. Various properties of the acrylic urethane clear coatings were also evaluated on the coating specimens. Adhesion property to a substrate, drying time, pot-life, pencil hardness, and 60° specular gloss of prepared paint showed quite good properties. Futhermore, prepared paint containing 10% of CLA showed quite good properties for adhesion, low viscosity and high hardness.

• Parasites, Hosts and Diseases
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• v.33 no.4
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• pp.331-340
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• 1995

Interstrain polymorphisms of isoenzyme profiles and mitochondrial (Mt) DNA fingerprints were observed among seven strains of Acnnthnmoeba isolated from different sources and morphologically assigned to A. polvphngn. Mt DNA ringerprints by eight restriction endonucleases (Bgl II, Sca I, Cla I, EcoR I, Xbo I, Kpn I, Sal I, and Sst I) revealed considerable interstrain polymorphisms . Isoenzyme profiles revealed considerable interstrain polymorphisms for acid phosphatase, lactate dehydrogenase, and glucose-6- phosphate dehydrogenase while those for glucose phosphate isomerase , leucine aminopeptidase , and malate dehydrogenase showed similarity Despite of the interstrain polymorphisms, the isoengyme profiles and Mt DNA fingerprints of the strain Ap were found to be identical with those of the strain .tones . Mt DNA fingerprinting was found to be highly applicable for the strain identification, characterization, and differentiation. Key words: Acanthnmoebn polyphcga, interstrain polymorphism, isoenzyme profiles , Mt DNA fingerprints, strain differentiation, strain identification.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.10
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• pp.1364-1373
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• 2012

Four crossbred (75% Holstein Friesian) lactating dairy cows, with an average live weight of $418{\pm}5$ kg and $36{\pm}10$ d in milk were randomly assigned according to a $2{\times}2$ factorial arrangement in a $4{\times}4$ Latin square design to evaluate the effects of cassava hay (CH) and rice bran oil (RBO) on feed intake, nutrient digestibility, ruminal fermentation, milk yield, and milk composition. Factor A was non-supplementation or supplementation with CH in the concentrate. Factor B was supplementation with RBO at 0% or 4% in the concentrate mixture. The four dietary treatments were (T1) control (Concentrate with non-CH plus 0% RBO; C), (T2) Concentrate with CH plus 0% RBO (CH), (T3) Concentrate with non-CH plus 4% RBO (RBO), and (T4) Concentrate with CH plus 4% RBO (CHRBO). The cows were offered concentrate, at a ratio of concentrate to milk production of 1:2, and urea-lime treated rice straw was fed ad libitum. Urea-lime treated rice straw involved 2.5 g urea and 2.5 g $Ca(OH)_2$ (purchased as hydrated lime) in 100 ml water, the relevant volume of solution was sprayed onto a 100 g air-dry (91% DM) straw, and then covering the stack with a plastic sheet for a minimum of 10 d before feeding directly to animals. The CH based concentrate resulted in significantly higher roughage intake and total DM intake expressed as a percentage of BW (p<0.05). Ruminal pH, $NH_3$-N, BUN and total VFA did not differ among treatments, while RBO supplementation increased propionate, but decreased acetate concentration (p<0.05). Furthermore, the population of total ruminal bacteria was significantly lower on the RBO diet (p<0.05). In contrast, the total ruminal bacteria and cellulolytic bacteria on the CH diet were higher than on the other treatments. Supplementation with CH increased (p<0.05) F. succinogens and R. flavefaciens populations, whereas the populations of B. fibrisolvens and M. elsdenii were increased on the RBO diet. In addition, supplementation with CH and RBO had no effect on milk production and composition in dairy cows, while fatty acid composition of milk was influenced by RBO supplementation, and resulted in significantly lower (p<0.05) concentrations of both short-chain and medium-chain FA, and increased (p<0.05) the proportion of long-chain FA in milk fat, as well as significantly increased cis-9, trans-11 CLA and total CLA. In conclusion, RBO or CH exhibited specific effects on DMI, rumen fermentation, microbial population, milk yield and composition in lactating dairy cows, which were not interactions between CH and RBO in the diets. Feeding lactating dairy cows with RBO could improve fatty acid in milk fat by increasing cis-9, trans-11 CLA.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.11
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• pp.1575-1589
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• 2017

Objective: This study was conducted to determine molecular structures related to carbohydrates and lipid in alfalfa hay cut at early bud, late bud and early flower and in the afternoon and next morning using Fourier transform infrared spectroscopy (FT/IR) and to determine their relationship with alfalfa hay nutrient profile and availability in ruminants. Methods: Chemical composition analysis, carbohydrate fractionation, in situ ruminal degradability, and DVE/OEB model were used to measure nutrient profile and availability of alfalfa hay. Univariate analysis, hierarchical cluster analysis (CLA) and principal components analysis (PCA) were conducted to identify FT/IR spectra differences. Results: The FT/IR non-structural carbohydrate (NSCHO) to total carbohydrates and NSCHO to structural carbohydrate ratios decreased (p<0.05), while lignin to NSCHO and lipid CH3 symmetric to CH2 symmetric ratios increased with advancing maturity (p<0.05). The FT/IR spectra related to structural carbohydrates, lignin and lipids were distinguished for alfalfa hay at three maturities by PCA and CLA, while FT/IR molecular structures related to carbohydrates and lipids were similar between alfalfa hay cut in the morning and afternoon when analyzed by PCA and CLA analysis. Positive correlations were found for FT/IR NSCHO to total carbohydrate and NSCHO to structural carbohydrate ratios with non-fiber carbohydrate (by wet chemistry), ruminal fast and intermediately degradable carbohydrate fractions and total ruminal degradability of carbohydrates and predicted intestinal nutrient availability in dairy cows ($r{\geq}0.60$; p<0.05) whereas FT/IR lignin to NSCHO and CH3 to CH2 symmetric stretching ratio had negative correlation with predicted ruminal and intestinal nutrient availability of alfalfa hay in dairy cows ($r{\geq}-0.60$; p<0.05). Conclusion: FT/IR carbohydrate and lipid molecular structures in alfalfa hay changed with advancing maturity from early bud to early flower, but not during the day, and these molecular structures correlated with predicted nutrient supply of alfalfa hay in ruminants.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.6
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• pp.819-826
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• 2009

An in vitro study was conducted to investigate the effect of malate or fumarate on fermentation characteristics, and production of conjugated linoleic acid (CLA) and methane ($CH_4$) by rumen microbes when incubated with linolenic acid (${\alpha}-C_{18:3}$). Sixty milligrams of ${\alpha}-C_{18:3}$ alone (LNA), or ${\alpha}-C_{18:3}$ with 24 mM malic acid (M-LNA) or ${\alpha}-C_{18:3}$ with 24 mM fumaric acid (F-LNA) were added to the 150 ml culture solution consisting of 75 ml strained rumen fluid and 75ml McDougall's artificial saliva. Culture solution for incubation was also made without malate, fumarate and ${\alpha}-C_{18:3}$ (Control). Two grams of feed consisting of 70% concentrate and 30% ground alfalfa (DM basis) were also added to the culture solution of each treatment. In vitro incubation was made anaerobically in a shaking incubator up to 12 h at $39^{\circ}C$. Supplementation of malate (M-LNA) or fumarate (F-LNA) increased pH at 6 h (p<0.01) and 12 h (p<0.001) incubation times compared to control and linolenic acid (LNA) treatments. Both malate and fumarate did not influence the ammonia-N concentration. Concentration of total VFA in culture solution was higher for M-LNA and F-LNA supplementation than for control and LNA treatments from 6 h (p<0.040) to 12 h (p<0.027) incubation times, but was not different between malate and fumarate for all incubation times. Molar proportion of $C_3$ was increased by F-LNA and M-LNA supplementation from 6 h (p<0.0001) to 12 h (p<0.004) incubation times compared to control and LNA treatments. No differences in $C_{3}$ proportion, however, were observed between M-LNA and F-LNA treatments. Accumulated total gas production for 12h incubation was increased (p<0.0002) by M-LNA or F-LNA compared to control or LNA treatment. Accumulated $CH_4$ production for 12 h incubation, however, was greatly reduced (p<0.0002) by supplementing malate or fumarate compared to the control, and its production from M-LNA or F-LNA treatment was smaller than that from LNA treatment. Methane production from LNA, M-LNA or F-LNA treatment was steadily lower (p<0.01 - p<0.001) from 3 h incubation time than that from the control, and was also lower for M-LNA or F-LNA treatment at incubation times of 6 h (p<0.01) and 9 h (p<0.001) than for LNA treatment. Methane production from LNA, however, was reduced (p<0.01 - p<0.001) from 3 h to 9 h incubation times compared to the control. Both malate and fumarate increased concentration of trans11-$C_{18:1}$ from 3 h to 12 h incubation (p<0.01), cis9,trans11-CLA up to 6 h incubation (p<0.01 - p<0.01), trans10,cis12-CLA at 3 h (p<0.05) and 12 h (p<0.01), and total CLA for all incubation times (p<0.05) compared to corresponding values for the ${\alpha}-C_{18:3}$ supplemented treatment (LNA). In conclusion, malate and fumarate rechanneled the metabolic $H_2 pathway to production of propionate and CLA, and depressed the process of biohydrogenation and methane generation. Linolenic acid alone would also be one of the optimistic alternatives to suppress the $CH_4$ generation.

• Microbiology and Biotechnology Letters
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• v.26 no.2
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• pp.117-121
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• 1998

Bacteriophage SC 921 of Lactobacillus plantarum, isolated from kimchi, showed high lytic effects at 0.2 M.O.I. level. The phage particle contained 4 major proteins (48, 34, 32, 29 kDa). Intact DNA of phage SC 921 is a double stranded linear molecule, and the genomic size is approximately 66.5 kilobase pairs (kbp). Restriction analysis of the genome showed that Sma I gave single site cut and Xba I gave 2 site cuts, while Cla I, Kpn I, and EcoR I formed 4, 5, and 6 cuts, respectively. Hind III digested phage DNA to many fragments. A restriction map of genomic DNA was constructed using the restriction endonuclease Kpn I, Sma I, and Xba I. Bacteriophage SC 921 was compared with B2 phage which had been reported to infect Lactobacillus plantarum ATCC 8014(KCCM l1322). Bacteriophage SC 921 differs from B2 phage at least in thr size of its genome and phage particle proteins.

• Journal of Life Science
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• v.15 no.4 s.71
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• pp.513-521
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• 2005

A bacterium producing five fibrinolytic isozymes was isolated from black bean chung kuk. The bacterium was identified as Bacillus subtilis BB-1 by 16s rDNA sequence homology search. A gene out of five fibrinolytic genes in the Bacillus subtilis BB-1 was cloned by shot-gun method. A Cla I DNA fragment of B. subtilis BB-1 chromosome was cloned in to pBluescript II SK(-) and showed the fibrinolytic activity to bacterial cells. The Cla I DNA fragment was sequenced and the sequences did not show homology with gene for protease or fibrinolytic enzyme genes in other organisms. The Cla I DNA fragment was reduced to 2,142 bp by activity-guided PCR cloning method. The optimum pH and temperature of the enzyme were 5.0 and $35^{\circ}C$, respectively. Substrate specificity of the fibrinolytic enzyme was detected in skim milk, casein, gelatin and blood agar plates. The activity of the enzyme was not detected with these substrates. Taken together, this enzyme is a new fibrinolytic enzyme and may be used to prevent thrombosis and arteriosclerosis.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.1
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• pp.122-130
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• 2010

Sensory analyses of pork samples from leg muscles of female pigs raised in New Zealand (n = 17) were conducted using trained and untrained Singaporean panelists. The New Zealand pigs included three dietary groups, with one diet including animal products (NZA), and two containing plant products only (NZP & NZP+), with the NZP+ diet containing a supplement (0.614%) containing conjugated linoleic acid (CLA), selenium, and vitamin E. The New Zealand pork was also compared with Indonesian pork as local reference samples (n = 6). Pork samples from the NZA group had the highest score for mutton flavour and aftertaste, and the lowest score for brothy aroma, brothy flavour, meaty flavour, lightness and juiciness by trained sensory panels. Samples from NZP and NZP+ were similar except the NZP+ group had a stronger stale flavour than the NZP group (1.34 vs. 0.57 on a 100-point scale; p<0.05). The first and second functions of a discriminant analysis based on trained-panel scores for 14 attributes accounted for 95.4% of the variance, with function 1 (83.7%) being related mainly to mutton aroma, mutton flavour and aftertaste. Based on a 20-member untrained panel, the NZA pork had the highest mutton aroma and mutton flavour intensities (p<0.01) and aroma and flavour that was less acceptable than that from the NZP group (p<0.05). The acceptability scores of Indonesian pork were not significantly different from those of New Zealand pork, but its scores for mutton aroma and mutton flavour were significantly lower than NZP. Overall acceptability was positively associated with acceptability of aroma (r = 0.906), juiciness (r = 0.888), and tenderness (r = 0.904), but negatively associated with intensities of mutton aroma (r = -0.478) and flavour (r = -0.551).

• Journal of the Korean Society for Precision Engineering
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• v.33 no.10
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• pp.821-828
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• 2016

Recently, the use of composite materials in the defense system has grown dramatically. The strength/weight and stiffness/weight ratios of composite structures are normally higher than of metals. Woven composites, especially, are increasingly considered for a variety of applications, because they offer good workability for complicated structures. HPW193/RS1222 is one of the most famous woven composites and has been used in many types of Korean military equipment, such as antenna pedestals and radar systems. In this study, we predicted the elastic modulus of HPW193/RS1222 using the principles of unidirectional composite stiffness predictions, such as ROM (Rule of Mixture), HSR (Hart Smith 10% Rule), CLA (Classical Laminate Analysis) and LAP (Laminate Analysis Program). We compared the dynamic characteristics with the experimental predictions and finite-element analysis (FEA). From our results we concluded that transversely isotropic materials are similar to isotropic materials when the shape of the composite structure is complicated.

• Journal of the korean Society of Automotive Engineers
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• v.24 no.5
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• pp.98-103
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• 2002

이제 카트 정렬과 휠 셋업에 필요한 최적의 변수들을 알아보았다. 실제 세팅은 위에서 언급한 내용 이외에도 많은 것들을 고려하여야 한다. 타이어 접지력의 세팅은 경기장, 날씨, 제품의 불 균일성 등을 고려하여 야 한다. 즉, 어떤 경기장은 코너의 반경이 다른 경기 장 보다 크며 어떤 경기장은 코너가 매우 많기도 하여 세팅을 상황에 맞게 하여야 하는 것이다. 각각의 변수를 세팅할 경우는 중간 값을 취하는 것이 바람직하여 이 중간 값을 취하는 것이 바람직하며 이 중간 값을 각각의 경기장의 특성에 맞추어 변화시키면 되는 것이다. 예를 들면, 접지력이 작게 발생되는 경기장(혹은 매우 추운날씨) 에서는 캐스터를 코기 하여 초기 회전 발생이 용이하게 할 수도 있다. 또한 토우인 값을 크게 하여 타이어가 마찰을 더욱 많이 발생하여 타이어의 온도가 급격히 상승하여 원하는 접지력의 수준에 용이하게 도달할 수 있게 하는 것이다. 그러나 이러한 세팅은 다른 핸들링 문제를 야기할 수 있다는 것을 이해하여야 하며 이러한 문제를 해결하는 또 다른 노력이 필요하게 되는 것이다. 가장 중요한 것은 후륜 내측으로부터는 조종 성능을 향상시키는데 필요한 접지력을 거의 기대하지 못한다는 것이며 마찰이 적게 발생하여 손쉽게 동력 손실을 초래하고 있다는 것이다. 그러므로 회전을 할 경우에도 속도를 낮추어서는 안되며 이렇게 하이야 핸들링이 매우 용이하게 되는 것이다. 그러나 위의 설명에서도 보았듯이 일부 세팅을 변경하면 여러 곳이 그 효과가 나타난다. 예를 들어 후륜의 간격을 변화시키면 카트에서 무게이동 뿐만 아니라 회전 시에 가속이나 감속에 의한 회전 토크의 효과도 달라지게 된다. 특정한 세팅의 변화가 어떻게 작용할 것이라는 확신을 가지고 있다고 할지라도 세팅에서 가장 중요한 것은 주행 기록이다. 여기서 설명되어진 많은 내용이 주행 기록을 향상시키기를 바라는 바이다.간이 육색과 총육색소 함량에는 영향을 미치지 않는 것으로 나타났다. 관능적 특성평가 중 육색과 육즙참출은 대조구와 비교하여 CLA급여 처리구가 유의적인 차이가 없었으나, 근내지방 축적 정도와 전체적인 기호성은 대조구에 비하여 CLA 급여 처리구가 유의적으로 높은 평가를 받았다(p<0.05). 간격은 술 후 1년 후까지도 지속적으로 감소하는 경향을 보였다. 따라서 이 기간동안에는 추적관찰이 필요한 것으로 생각된다.경미하게 나타났으며, 이는 2% 흥국 첨가식이의 섭취로 인한 bromobenzene 대사 및 유해산소 해독의 촉진에 기인되기 때문일 것으로 생각된다.다.과 및 지질과산화억제효과의 순과 일치하였다. 총 flavonoid 함량은 DPPH 라디칼 제거효과에 대한 $IC_{50}$/ 값과 높은 상관관계(r=-0.9924, p<0.01)를 나타내었다.이 우수한 심근보호 효과를 나타내나, 허혈시간이 2시간을 초과하면 심근의 혈역학적 기능과 미세구조의 변화는 중등도의 저온(22∼24$^{\circ}C$)에서 유의하게 악화되었다. 이 같은 결과로 볼 때 심근 허혈시간이 2시간을 초과한다면 심근 온도를 낮추어야 할 것으로 판단된다. 7.2, with 64.0% of office workers having an average level between 6- and 9. The degree of stress was higher for females than males, for unmarried salaried and hot-tempered persons. Those not doing exercise were subject to the highest levels of stress, and those a having sufficient sleep were found to be subject to less stress.