• Magazine of the Korea Concrete Institute
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• v.11 no.2
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• pp.209-220
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• 1999

This paper is aimed to evaluate the effectiveness of flexural toughness of slab panel structures($60{\times}60{\times}10$) reinforced by steel fiber instead of wire mesh. Steel fiber used in this study is double hooked Dramix type fiber. And the fiber length is 60mm, diameter is 0.8mm, Various assessment methods of toughness index are used to estimate the proper effectiveness. In this experimental study, we find that Johnston, JCI-SF4 and EFNARC method are more effective to assess the flexural toughness of slab panels than the others. And the steel fiber is very effective alternative material to reinforce slab panel structures instead of wire mesh. Fiber volume fraction of 0.5~0.75% is more useful than the others in enhancing the post-peak energy absorption and toughness index by Johnston's $I_{5.5}$ assessment method. And the slab panels reinforcing with steel fiber are more resistant to crack propagation than wire mesh reinforcing slabs.

• Korean Journal of Animal Reproduction
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• v.18 no.3
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• pp.217-228
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• 1994

These experiments were carried out to establish the optimal condition of electrostimulatin inducing cell fusion and oocyte activation for nuclear transplantation in mouse embryos. Eggs selected for cell fusion or activation by electrostimulation were equilibrated for 5~10 min. in 0.3M sucrose solution and electrostimulated for 60$\mu$sec using 1 pulse of 60, 70, 80, 90 or 100 volts DC with electrodes 0.2 mm apart. Then they were cultured in 20${mu}ell$ dropsof Tyrode's solution. The results of these experiments are as follows : 1. When one pulse of 60, 70, 80, 90 or 100 volts DC for 60$\mu$sec were applied to 2-cell embryos for fusion of blastomeres, fusion rates were 50.0, 81.7, 91.7, 100 and 100%, respectively ; and developmental rates of fused embryos to blastocyst were 76.7 to 81.5%. Higher fusion rates were observed in 90V and 100V. 2. The average cell number in fused embryos developed to blastocyst was about half of the cell number in diploid controls; and the cell number decreased with increasing of voltages. 3. When pulse numbers were increased, fusion rates improved, but developmental rates were not signficiantly different from the group for which the number of pulse was not increased. And the cell number of blastocyst decreased even more. 4. Oocytes aged for 6hrs after ovulation were electrostimulated for oocyte activation by the same method used for cell fusion. Rates of oocyte activated by electrostimulation were 45.3 to 60.4%, and fragmentation rates were 7.5~15.1%. The lysis rates were 17.0~34.0%. The results of these experiments indicate that the optimal condition for achieving cell fusion and activation is 1 pulse, duration 60$\mu$sec in 90 Volt. The results also show that this condition is suitable for nuclear transplantation using mouse eggs.

• Korean Journal of Veterinary Research
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• v.30 no.2
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• pp.203-214
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• 1990

A total of 166 strains of Salmonella (S) typhimurium var copenhagen isolated from pigeons (164 strains) and aquatic birds (2 strains) were examined for the biochemical characteristics and plasmid profiles. All the strains were sensitive to ampicillin, chloramphenicol, gentamicin, kanamycin and sulfadimethoxine. But 13 strains(7.8%) were resistant to streptomycin (Sm), 2 (1.2%) to tetracycline, 2 (1.2%) to rifampicin, and 1 (0.6%) to nalidixic acid. Among drug resistant strains, only one strain resistant to Sm contained conjugative R plasmid which was fertility inhibition and incompatibility group $I_{\alpha}$. All the strains were sensitive to cobalt chloride, cupric sulfate, lead nitrate, mercuric chloride and silver nitrate. Of 166 isolates, 6 (3.6%) were resistant to sodium arsenate and 1 (0.6%) to potassium tellurite. Among 166 isolates, 1 (0.6%) was colicinogenic, 12 (7.2%) sucrose fermenters, and 166 (100%) maltose fermenters. Plasmid profiles were confirmed as being 4 or 5 plasmids, and their molecular weight ranged 3.2 to 60 megadalton (MD). All the strains harbored 60 Md plasmid. There are three patterns by the plasmid profile, 150 isolates (90.4%) were pattern I (3.2, 3.5, 33, 60Md), 14 (8.4%) pattern II (3.2, 3.5, 29, 60Md), and 2 (1.2%) pattern III (4.2, 7.8, 8.5, 15, 60Md). S typhimurium var copenhagen strains containing 60Md plasmid were resistant to killing by 90% normal guinea pig serum.

• Journal of Biosystems Engineering
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• v.31 no.6 s.119
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• pp.506-513
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• 2006

The effects of ultrasound stimuli on the germination and sprout growth of brown rice were investigated. Ultrasound was applied to brown rice at the frequencies of 28, 40, and 60 kHz before germination test and it was germinated in three methods (Type I, II and III). Type I was to soak brown rice into water for 60 hours. Type II was to expose brown rice to air for 48 hours after soaking them into water for 12 hours. Type III was a repetitive method of water-soaking and air exposure for 12 hours respectively. The most effective method for the germination was Type III without ultrasound. However, Type I was a best method after ultrasound treatment. As power of ultrasound increased, sprouts grew faster after brown rice were treated in 40%, 70%, and 100% power (0.137, 0.241, and 0.344 $W/cm^2$) at 40 kHz. The good treatments for fast sprout growth of brown rice at each frequency were the 28 kHz-10min group, the 40 kHz-5min group, and the 60 kHz-20min group of Type I. The best effective treatment was the 40 kHz-5min group at 0.344 $W/cm^2$ and at that condition the time required for sprout growth of 2.5 m was 51.9 hours. The ultrasound stimuli was very effective in the beginning of the rice germination, and the germination ratio was more than 95% in all ultrasound treatments.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.6
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• pp.784-793
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• 2004

Major objective was to evaluate three doses of bST (POSILAC(R)) injected into Holstein cows during the transition period and through 56 d of lactation for potential to improve DMI, BCS, BW, metabolites, hormones, IGF-I and milk production. Biweekly injections of bST (0, 5.1, 10.2, or 15.3 mg bST/d) began 28 d before expected parturition and continued through 56 d postpartum. Twenty-three of the 25 multiparous Holstein cows assigned randomly to four groups completed experiment (7, 5, 6 and 5 cows/group, respectively). The DMI, BW and BCS were recorded weekly throughout the prepartum and postpartum periods and blood samples were collected thrice weekly for analyses of ST, insulin, $T_{4}$, $T_{3}$, IGF-I, glucose and NEFA. Milk yields were recorded daily through 60 d postpartum and milk components measured once weekly. Mathematical model for data analyses for prepartum and postpartum periods included treatment, calving month, and the two-factor interaction. Cows injected with 10.2 and 15.3 mg bST prepartum had greater mean prepartum concentrations of ST and IGF-I. Prepartum injections of bST did not affect prepartum BW or BCS. On average, cows injected postpartum better maintained their BCS during first 60 d of lactation (3.15$\pm$0.06, 3.12$\pm$0.007, 3.20$\pm$0.006 and 3.58$\pm$0.009). Treatments did not affect mean prepartum DMI but cows injected with 15.3 mg bST/d had greatest DMI and greatest mean daily MY during the first 3 wk and tended to be greater during first 60 d of lactation. Cows injected with two highest bST doses (10.1 and 15.2 mg/d) had greater mean postpartum concentrations of ST and $T_{3}$, but IGF-I, $T_{4}$, glucose and NEFA did not differ across groups. No adverse effects of bST treatment were observed.

• YAKHAK HOEJI
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• v.50 no.2
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• pp.136-143
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• 2006

Roots of Scutellaria baicalensis have been used for fever remedy; diuresis, antiphlogistic. For the investigation of the active component from aerial parts of Scutellaria baicalensis, MeOH extracts from aerial parts of Scutellaria baicalensis were suspended with $H_2O$, and partitioned by $CHCl_3$. In order to investigate the efficacy of antioxidative activity the activity guided fraction and isolation of physiologically active substance were peformed. Its $H_2O,\;30\%,\;60\%$ MeOH and MeOH fractions were examined on antioxidative activity using DPPH method and TBARS assay; It was revealed that $30\%\;and\;60\%$ MeOH fractions have significant anti-oxidative activity. its fractions testing type I allergy, compound 48/80 induced systemic anaphylaxis was applied. As a result, compared with reference (cromolygate), these fraction significantly inhibited systemic anaphylaxis by $71\%\;and\;57\%$, respectively. From $30\%,\;60\%$ MeOH fraction, five compounds were isolated and elucidated apigenin 6-C-${\alpha}$-L-arabinopyranosyl-8-C-${\beta}$-D-glucopyranoside (isoschaftside, I), scutellarein 7-O-${\beta}$-D-glucuronopyranoside (scutellarin, II), apigenin 7-O- ${\beta}$-D-glucuronopyranoside (III), isoscutellarein 8-O-${\beta}$-D-glucuronopyranoside (IV), kaempferol 3-O-${\beta}$-D-glucopyranoside (V) through their physicochemical data and spectroscopic methods. We measured radical scavenging activity with DPPH method and anti-lipid peroxidative efficacy on human LDL with TBARS assay. [$I] showed antioxidant activities in order. Type I allergy compound 48/80 induced systemic anaphylaxis was applied. $[V inhibited systemic anaphylaxis in order.

• The Korean Journal of Mycology
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• v.21 no.4
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• pp.301-309
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• 1993

An alkalophilic Cephalosporium sp. RYM-202 capable of producing cellulase components was isolated from soil. This organism grew best at an initial pH 9.0 and produced cellulase maximal at an initial pH 9.5-10.0. Three carboxymethyl cellulases(CMCases), P-I-I, P-I-II and P-II-I, were partially purified by DEAE-Sephadex A-50 ion exchange column followed by Sephadex G-150 gel filtration. The optimum pH values for activity were 7.5 for P-I-I, 8.0-9.5 for P-I-II and 7.5-10.0 for P-II-I. All CMCases were stable between pH 4.5 and 12.0. Temperature optima for activity ranged between 40 and $60^{\circ}C$ and more than 50% of the maximum activity was observed at $20^{\circ}C$ for both of P-I-I and P-II-I. The activity of CMCases was significantly stable in the presence of various laundry components, such as, surfactants, chelating agents and alkaline proteinases.

• Korean Journal of Animal Reproduction
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• v.23 no.4
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• pp.323-331
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• 1999

The effects of insulin-like growth factor-I (IGF-I) and cumulus cells during in vitro maturation in porcine oocytes were examined. When follicular oocytes were cultured in medium with different concentrations of IGF-I, maturation rates were 60, 61 and 62 and 72% for 0, 15 and l0ng/$m\ell$ IGF-I. In medium with 10ng/$m\ell$ IGF-I, maturation rates were not significantly difference between oocytes with (68%) and without (52%) cumulus cells during the culture. In medium with-out IGF-I, however, the maturation rates in oocytes with cumulus cells (63%) was significantly (P＜0.05) higher than oocytes without cumulus cells (32%). On the other hand, when IGF-I was added for first 24 h period or later 24 h period of culture, maturation rates were higher in oocytes with (61 and 49%) that than without (49 and 45%) cumulus cells. In experiment used medium without fetal calf serum (FCS) and porcine follicular fluid (PFF), the maturation rates in oocytes with cumulus cells for 48 h (48 and 67%) or first 24 h (46 and 63%) period after culture were significantly (P＜0.01) higher than in oocytes without cumulus cells (16 and 18%) in the presence or absence of IGF-I. These results indicated that cumulus cells is essential on maturation in vitro in porcine oocytes, but IGF-I can promote oocytes maturation of oocytes without cumulus cells in medium with FCS and PFF.

• The Korean Journal of Nuclear Medicine
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• v.32 no.1
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• pp.50-60
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• 1998

I-123 labelled fatty acids are suitable for investigation of regional myocardial metabolism, so they are on the clinical trial. However, the precise properties of these materials are not characterized yet. We have synthesized phenylpentadecanoic acid and labeled this compound with I-123. The purpose of this study was to examine the stability, biodistribution, metabolism and SPECT imaging of [I-123]15-(p-iodophenyl)pentadecanoic acid(I-123-IPPA) that we made. The stability test of I-123-IPPA in serum of rat, mouse and human showed no free I-123 after 1 hour. In biodistribution study in mice for various time intervals after injection(5, 10, 15, 30, 60 minutes), uptake in myocardium was 14.5%ID/g(5 min), and 1.9%ID/heart(5 min), while uptake in muscles was 2.6%ID/g(5 min). Myocardium to blood ratio and myocardium to lung ratio increased for 5 min after injection and then decreased rapidly. Chromatographic data of rat blood and urine showed that little PPA was found in blood and urine at 15-20 min after injection. The myocardial I-123-IPPA SPECT images of a dog with myocardial infarction showed defects similar to those of Tc-99m-MIBI and F-18-FDG. These data suggest that I-123-IPPA is quite stable in vitro and shows favorable biodistribution in mice. SPECT imaging with I-123-IPPA demonstrated infarct zone as photon defect in dog model of myocardial infarction. I-123-IPPA may be used for the evaluation of fatty acid metabolism in clinical trials in Korea.

• Korean Journal of Veterinary Research
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• v.34 no.4
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• pp.735-744
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• 1994

Catheters were placed into the external jugular veins of immature female rats. On the following day (day 28 of age), the animals were injected subcutaneously with pregnant mare serm gonadotropin(PMSG): 4IU(control) or 20IU(superovulation). Each animal was sequentially bled at Ohr and 12hr and subsequently at 6hr intervals until sacrifice at 72hr after PMSG. The superovulatory dose of PMSG significantly(P<0.05) increased the ovulatory response by 4.0 fold above controls. On the other hand, superovulated oocytes displayed considerably different stages of meiotic maturation: prophase I (14.7%), anaphase I (36.2%), telophase I (10.3%), metaphase I/II (32.4%), while in control rats a majority of the oocytes examined(94.0%) consistently showed a metaphase II configuration. Serum luteinizing hormone(LH) levels were determined by RIA. Both groups exhibited a similar time relationship with two distinct peaks: an initial slight rise at 0-18hr and a second sharp rise at 54-60hr. However, there was a marked change in the magnitude of LH levels between the two groups. In superovulated animals, prior to the second peak, overall LH levels were significantly(P<0.001) higher than controls. In contrast, at the peak occurring at 60hr, LH concentrations were significantly(P<0.001) reduced by 54% below that of control. Additionally, a maximum increase of mean ${\Delta}LH$ between two peaks was much less in superovulated as compared to control rats. The initial prolonged elevation of serum LH before 54hr in superovulated rats was found to result from actual cross-reaction of the injected PMSG with LH antibody in the assay, while a precipitous second elevation between 54hr and 60hr resulted primarily from an endogenous LH surge. This study clearly defines time-course features of serum LH in PMSG-treated rats. The overall results indicate that, following superovulatory treatment with PMSG, the increased ovulatory response is primarily associated with PMSG-derived intrinsic gonadotropin, and that the recovery of immature or asynchronously mature oocytes at ovulation may reult from the circulatory alteration of LH activity characterized by an initial prolonged elevation of serum LH and its subsequent attenuation.