• Korean Journal of Microbiology
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• v.21 no.4
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• pp.221-228
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• 1983

An improved procedure for the rapid purification of glucose-6-phosphate dehydrogenase from extracts of Saccharomyces cerevisiae was developed by using affinity chromatography. Among six affinty media tested, $NADP^+ -agarose$ and Affi-gel Blue were more effective than others (i.e., Affi-gel Red, AMP-agarose, ATP-agarose, and $NAD^+ -agarose$). Conditions to desorb the enzyme bound to the affinity media were examined to increase the purity as well as yield. The best result was obtained when the column was developed with a linear gradient of KCl (0-1.0M). In case of Affi-gel Blue, introduction of $NAD^+$ (15mM) washing step prior to the salt gradient was most effective to remove $NAD^+ -binding$ proteins. For a large scale preparation of G-6-P dehydrogenase higher recovery was obtained by Affi-gel Blue than $NADP^+ -agarose$, however, the purity of the enzyme was decreased by 10 times if the former was used as the affinity medium. The capacity of Affi-gel Blue for G-6-P dehydrogenase was found to be 5 times higher than that of $NADP^+ -agarose$. Furthermore Affi-gel Blue could be reused repeatedly and its preparation is relatively easier and less expensive than $NADP^+ -agarose$.

• Journal of the Korean Ceramic Society
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• v.39 no.4
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• pp.386-393
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• 2002

Fabricatio of the potassium-titanate fiber with K2O${\cdot}nTiO_2$ composition and coating of electrically conductive Sb-doped $SnO_2$ (ATO: Antimony Tin Oxide) layer on the fiber on the fiber were the fiber were the aims of this work. The fiber fabricated by slow-cooling technique showed the mean length of $15{\mu}m$ and mean diameter of $0.5{\mu}m$. Three different coating methods i.e, sol-gel, co-precipitation and urea technique, were attempted to coat the conductive ATO layer on the potassium-titanate fiber. The influences of coating method, concentrations of ATO(5∼70wt%) and Sb (0∼20wt%), temperature in the range of $450\;to\;800^{\circ}C$, number of washing (3∼4 times) on the resistivity of the ATO coated fiber were examined in details. The fiber coated ATO by coprecipitation exhibited lower resistivity of 103${\Omega}{\cdot}$cm at the 30 wt% of ATO, and showed nearly constant low value of $60{\Omega}{\cdot}cm\;to\;90{\Omega}{\cdot}$cm at the higher concentration of ATO.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1350-1356
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• 1998

An attempt was made to investigate the effects of additives (3%) such as egg white, soybean protein, corn starch and Read Amity-N (green bean starch 85%+psyllium husk 10%) on the thermal properties and gel structures of mackerel surimi and to examine the quality of surimi by using differential scanning calorimetry (DSC), rheometry and scanning electron microscopy (SEM). The thermal transition temperatures of mackerel surimi protein were 40, 52, 67 and $79^{\circ}C$ after those temperatures were changed to 37, 46, 57 and $76^{\circ}C$ after adding salt (3% NaCl). Addition of Read Amity-N and corn starch to surimi showed new peak at the temperature of $90^{\circ}C\;and\;92^{\circ}C$, respectively. The enhancing effects of gel strengths of mackerel surimi cooked gels prepared from adding four kinds of additives, respectively, were egg white > soybean protein > Read Amity-N > corn starch in order. Scanning electron microscopy showed a difference in fine structures between the cooked gels which were prepared with and without additives. Dispersion profiles of protein were more thick in cooked gel prepared with additive than in cooked gel prepared without additive.

• Tuberculosis and Respiratory Diseases
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• v.61 no.1
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• pp.54-59
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• 2006

Background: Although there have been several studies regarding the clinical value of an automated TB-PCR study using sputum, bronchial washing, and other body fluid samples for the detection of pulmonary tuberculosis, there are only a few reports on the use of fresh tissue samples. Materials and methods: The acid-fast bacilli stain(AFB), tuberculosis culture, automated TB-PCR study, and histopathology examination were performed in 42 fresh tissue samples. Results: Among the 42 cases, 18 cases were diagnosed with tuberculosis based on the clinical findings. Sixteen of the 18 cases were TB-PCR positive and of these 16 cases, only 2 cases were positive in the AFB stain or culture study. However, all 18 cases showed the histopathology findings of chronic granulomatous inflammation that was compatible with tuberculosis. Based on the clinical findings, the sensitivity, specificity, positive predictability, and negative predictability of the automated TB-PCR study were 88.9%, 100%, 100%, and 92.3% respectively. Conclusion: An automated TB-PCR assay is an important diagnostic tool for diagnosing tuberculosis in fresh tissue samples.

• The Korean Journal of Physiology
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• v.2 no.2
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• pp.83-92
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• 1968

A study was planned to evaluate the effects of removal of the cingulate cortex upon the occurrence of any behavior commonly displayed by the rat, and to compare the effects of cingulectomy with those of removal of the parietal, parieto-occipital, or occipital regions. The subjects were 54 male albino rats (Holtzman strain, body weight $200{\sim}330\;gm$) including 14 rats in which the cingulate gyri between splenium and genu of the corpus callosum were bilaterally ablated by suction (cingulate group), 9 animals which had their parietal cortices (chiefly area 7) partially removed (parietal group), 9 rats whose parietal and occipital regions (chiefly areae 7 & 17), 13 animals in which the occipital cortices (chiefly area 17) were removed bilaterally (occipital group), and 9 normal rats (normal control group). Eighteen observation cages, each of which housed a subject and was provided with food and water ad lib., were arranged in 6 rows on a rack and the behavior of each subject was scanned by an observer at a distance of 1.5 m from the rack. The observer scanned the first and second rows 6 times in 1 min, then proceeded to the 3rd and 4th rows, scanning for another 1 min, and finally to the 5th and 6th rows. The speed of scanning was such that behavioral observations of all of the 18 rats were completed in 3 min, each subject receiving 6 observations. The scanning was repeated every 3 min for 18 min, which constituted one observation session and was followed by a 72 minutes' recess. The whole procedure was repeated through 24 hours so that a total of 576 behavioral observations were made on each subject in 16 observation sessions. Behaviors checked were sleeping, lying, lying and sniffing, standing, standing and sniffing, exploring, eating, drinking, grooming (included were washing, licking, and scratching), and others. Results obtained were as follows: 1. The cingulate group ate significantly more often than the normal control, the parietal, and the parieto-occipital groups. 2. Exploration was significantly less frequent in the cingulate group than in the normal control, the parietal, and the occipital groups. There was, in the case of the cingulate group, a significant negative correlation between the occurrence of eating and the exploratory activity. 3. The general activity, as judged from the value obtained by adding the occurrence of exploration, eating, drinking, grooming, and standing and sniffing, was significantly increased in the cingulate group compared with those of any other groups including the normal control. 4. Though statistically insignificant, the cingulate group slept least often among all the animal groups tested. 5. The parieto-occipital group tended to groom less, and the parietal group to eat less often than the normal control group did, but the difference was not significant. There were no significant differences among all the groups except the cingulate group as regards other behaviors analyzed. Based on the above results, it was inferred that the cingulate cortex exerts an inhibitory influence upon the occurrence of eating and general activity, while it tends to facilitate the occurrence of sleep.

• The Korean Journal of Physiology
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• v.16 no.1
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• pp.13-23
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• 1982

Effects of external pH and potassium concentrations on the electrical and mechanical properties were investigated on rabbit papillary muscle. Papillary muscles were perfused in horizontal chamber with Tris Tyrode solutions and action potential along with isometric tension was recorded simultaneously. Potassium concentrations were varied between 1 and 12 mM at low(6.9), normal(7.4) and high (7.9) external pH. The following results were obtained: 1) On rasing the potassium concentration from 1 to 12 mM resting membrane potentials decreased from $-88.8{\pm}2.8$ to $-66.4{\pm}1.2\;mV$ at normal pH and the amplitude of action potential decreased from $115.1{\pm}0.7$ to $97.5{\pm}2.8\;mV$. On lowering the potassium concentration, membrane hyperpolarized and at 1 mM potassium concentration resting potentials were $-107{\pm}2.2\;mV$. Duration of action potential especially $APD_{60}{\sim}APD_{90}$ increased($APD_{90}$: $214{\pm}15.8\;ms$ at 1 mM $K^+$ to $287{\pm}18.1\;ms$ at 12 mM $K^+$). 2) During acidosis membranes hyperpolarized by more than 20 mV within 1 min. and then slow recovery was observed during the following 10 min. During alkalosis membranes depolarized about 10 mV, which were maintained until washing with normal Tyrode solutions. 3) On lowering the external pH(7.9-6.5), duration of action potential increased progressively and it was most prominent at pH 6.5 and $K^+$ 1mM. 4) Magnitude of developed tension was $0.6{\pm}0.14\;g/mm^2$ at normal pH and potassium concentration (stimulus frequency : 60/min). Relative isometric tension to normal value increased along the increment of stimulus frequency($44.2{\pm}4.2%$ at 6/min to $271{\pm}86.7%$ at 180/min). Force-frequency relations were altered quantitatively during the perfusion with different external pH solutions. 5) Developed tension did not show marked variation within the range of $2{\sim}8\;mM$ potassium concentrations. Positive inotropism was observed at less than 2 mM $K^+$ and negative inotropism beyond 12 mM $K^+$ concentrations. From the above results we concluded that the effects of potassium ion concentration on electrical and mechanical properties of rabbit papillary muscle are related to the changes in surface negative charge due to acid base disturbances.

• Journal of Embryo Transfer
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• v.9 no.1
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• pp.7-14
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• 1994

The present experiments on cryopreservation were designed to examine the effects of solution toxicity, equilibration time and cell stages on the post-thaw survival of bovine IVF embryos. The oocytes were matured in vitro(IVM) for 24 hrs. in TCM-199 supplemented with 35 $\mu$g /ml FSH, 10 $\mu$g /ml LH, 1 $\mu$g /ml estradiol-17$\beta$ and granulosa cells at 39$^{\circ}C$ under 5% $CO_2$ in air. They were fertilized in vitro(IVF) by epididymal spermatozoa treated with heparin for 24 hrs., and then the zygotes were co-cultured in vitro(IVC) with bovine oviductal epithelial cells for 7 to 9 days. The bovine IVF embryos were exposed to the EFS solution in one step at room temperature, kept in the EFS solution during different period for toxicity test, vitrified in liquid nitrogen, and thawed rapidly. 1. after the bovine blastocysts were exposed to EFS solution for 2 min. at room temperature and then they were washed in 0.5 M sucrose solution and TCM-199, they were cultured to examined cryoprotectant induced injury during exposure, Most of the embryos(95.0%) developed to reexpanded blastocoels. However, when the exposure time was extended to 5 and 10 min, these development rates dropped dramatically in 5 min. (69.5%) and 10 min. (47.4%), respectively, 2. When the bovine IVF embryos were vitrified in EFS solution after the equilibration for 1 and 2 min. exposure, The embryos to have reexpanded blastocoels following thawing, washing and culture processes were found to he 82.6 and 73.9%, respectively. However, when the exposure time was extended to 3 min, this survival rate dropped to 18.2%. The optimal time for equilibration of bovine IVF blastocysts in EFS solution seemed to he 1~2 min. 3. When the bovine IVF embryos were equilibrated for 1 min. the significantly (P<0. 05) higher post-thaw survival rates were obtained from the embryos of blastocyst stage(81.3%) than morulae stage(5. 1%). The optimal cell stage for viterification with EFS solution proven to he blastocyst stage in bovine IVF embryos. 4. The number of blastomeres of blastocyst stage was examined with nuclear staining with Hoechst 33342 during 7 to 9 days post-insemination. The cell counts of frozen bovine IVF embryos were found significantly(P$\geq$7.5 and those of the fresh embryos 76.6$\geq$7. 1, which were cultured in the sarne period and conditions as frozen embryos.

• Journal of Embryo Transfer
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• v.32 no.3
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• pp.235-241
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• 2017

To preserve genetic materials, cryopreservation of the semen from live animals is the main technique to establish cryo-banking system which could be used for artificial insemination and embryo transfer. However, the population of Korean black goat (KBG) becomes to dwindle in number and is now faced genetic erosion by crossbreeding with non-native breeds in small KBG farms. In this study, simple freezing method was used to preserve frozen semen from KBG using spermatozoa of cauda epididymis (CE) and electro-stimulated semen (ES). The negative effects of seminal plasma on fresh sperm was confirmed using precipitation test of Triladyl egg yolk diluent and sperm viability after thawing was compared between CE and ES spermatozoa. When seminal plasma of fresh ES semen was washed with semen washing media (SWM), the rates of live sperm shown no significant difference between CE and ES spermatozoa before freezing. However, the survival rate of frozen/thawed CE sperm was higher than ES ($74.6{\pm}10.6%$ vs $53.8{\pm}5.2%$) with significant difference (p < 0.05). The results of longevity test on frozen/thawed sperm from CE showed healthier sperm than ES. Therefore, spermatozoa from CE could be used for cryo-banking system in KBG lines. The more studies are needed to increase survival rate of ES semen.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.6
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• pp.928-934
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• 2008

The objective of this study is to investigate the dyeing properties of safflower yellow dye on silk for the standardization of dyeing process and color reproducibility. Yellow colorants were water-extracted from safflower petals, concentrated, and freeze-dried to obtain colorants powder. The effects of dye concentration, dyeing temperature, and pH of dye bath were studied in terms of dye uptake and shade. Fastness to dry cleaning and light was evaluated. Dye uptake increased with raising temperature and brighter and more vivid yellow shade was obtained when dyed at $30^{\circ}C$. As colorants concentration increased, dye uptake increased progressively and the shade got darker and deeper. Maximum color strength was obtained at pH 3.5. It was speculated that the adsorption of colorants seemed to occur mainly by hydrogen bonding and physical force at pH 5.5 and by ionic bonding as well as hydrogen bonding below isoelectric point(pH 3.8-4.0). The results of reproducibility test showed acceptable color difference in the range of $1.11{\sim}2.01$. Washing fastness was fairly good as 4/5 rating, while light fastness was 2/3 rating.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.10
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• pp.957-964
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• 2010

The deactivated catalyzed diesel particulate filter-trap (DPF) was remanufactured by ultrasonic wave treatment with various prepared solutions, followed by active component re-impregnation, and the emission control performance and surface properties of remanufactured DPF were studied at various remanufacturing conditions. The proper ultrasonic wave cleaning time at various prepared solutions and optimal re-impregnation amounts of active component for the best emission control performance of DPF were investigated and its performance tests were also carried out with various temperatures for the conversions of CO, THC (total hydrocarbon) and PM (particulate matter) by catalytic reaction test unit using bypass gas from the diesel engine dynamo system. It was found that the emission control performance of DPF remanufactured with the high-temperature air washing, ultrasonic wave cleaning at acid/base solutions and active component re-impregnation method was recovered to 95% level of its activity compared to that of the fresh DPF, which was caused by removing the deactivating materials from the surface of the DPF, through the analyses of performance test and their surface characterization by Optical microscope, EDX, ICP, TGA, and porosimeter.