• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.505-512
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• 2006

Characteristics of particle holdup and heat transfer were investigated in a liquid-particle swirling fluidized bed whose diameter was 0.102 m and 2.5 m in height. Effects of liquid velocity, particle size and swirling liquid ratio($R_s$) on the particle holdup and immersed heater-to-bed overall heat transfer coefficient were examined. The particle holdup increased with increasing particle size and swirling liquid ratio but decreased with increasing liquid velocity.The local particle holdup was relatively high in the region near the heater when the $R_s$ value was 0.1~0.3, but the radial particle holdup was almost uniform when the $R_s$ value was 0.5, whereas, when the $R_s$ value was 0.7, the local particle holdup was relatively low in the region near the heater. The heat transfer characteristics between the immersed heater and the bed was well analyzed by means of phase space portraits and Kolmogorov entropy(K) of the time series of temperature difference fluctuations. The phase space portraits of temperature difference fluctuations became stable and periodic and the value of Kolmogorov entropy tended to decrease with increasing the value of $R_s$ from 0.1 to 0.5. The Kolmogorov entropy exhibited its maximum value with increasing liquid velocity. The value of overall heat transfer coefficient(h) showed its maximum value with the variation of liquid velocity, bed porosity or swirling liquid ratio, but it increased with increasing particle size. The value of K exhibited its maximum at the liquid velocity at which the h value attained its maximum. The particle holdup and overall heat transfer coefficient were well correlated in terms of dimensionless groups of operating variables.

• Journal of Life Science
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• v.28 no.1
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• pp.17-25
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• 2018

In this study, we examined the efficacy of the immune regulation of ${\beta}$-1,3/1,6-glucan and Lactobacillus plantarum LM1004 on atopic dermatitis models. The oral administration of ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004 on mice significantly decreased the amount of scratching, leakage to evans blue, and concentrations of serum immunoglobulin E (IgE) and histamine compared with the atopic dermatitis - induced group. When atopic dermatitis was induced, the transcription factors (GATA-3, retinoic acid-related orphan receptor ${\gamma}$ T [$ROR{\gamma}T$]) and cytokines (interleukin-4 [IL-4], IL-17) of Th2 and Th17 cells were overexpressed at the transcriptional level, and they significantly decreased with oral administration of ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004. In addition, ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004 were shown to modulate the immune balance by increasing the expression of Th1 and Treg transcription (T-bet, forkhead box p3 [Foxp3]) and cytokines (interferon-${\gamma}$ [IFN-${\gamma}$], transforming growth factor-${\beta}$ [TGF-${\beta}$]). Galectin-9 and filaggrin were significantly lower in the atopic dermatitis - induced group and significantly higher in the ${\beta}$-1,3/1,6-glucan-treated group. In contrast, thymic stromal lymphopoietin (TSLP) was highest in the atopic dermatitis-induced group, while mice that were orally administered ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004 showed similar TSLP levels to the control group. These results indicate that ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004 have immunomodulatory effects and atopic dermatitis improvement effects in an animal model of atopic dermatitis. Therefore, it is expected that ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004 can be used as natural materials in the treatment of atopic dermatitis.

• Korean Journal of Poultry Science
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• v.39 no.4
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• pp.291-295
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• 2012

The use of methylacetamide (MA) as a cryoprotective agent for freezing Korean Native Black rooster Ogye semen was examined with artificial insemination. The diluted Ogye semen with HS-1 was subjected for 2 step dilution method of cryopreservation in which the final concentration of MA was adjusted to 7.5%. The sperm viability after thawing was reduced from $95.17{\pm}0.93%$ to $55.93{\pm}1.38%$ which was confirmed by live-death analysis based on Fluorescence-Activated Cell Sorting (FACS). The rates of fertilized eggs with fresh or frozen-thawed semen were reduced from $94.98{\pm}3.93%$ to $66.36{\pm}8.43%$ at day 7 with significant difference. However, the hatching rates of experiments at day 21 did not shown difference between $92.64{\pm}2.33%$ and $90.45{\pm}8.05%$ (P<0.05). With these results, the utilization of MA for freezing of Ogye spermatozoa could affect on viability of frozen-thawed semen but not on the fertility of lain eggs and hatchability of fertilized eggs and also provide possible tools of freezing for poultry genetic resource conservation.

• Journal of Food Hygiene and Safety
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• v.17 no.1
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• pp.36-44
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• 2002

GC-l00X is non-corrosive alkaline ionic water (pH 12). It is composed of hydroxyl radicals and supplemented with xylitol. Its antimicrobial activity was examined against 6 major food-borne pathogens; Staphylococcus aureus FRI 913, Salmonella enterica serova Enteritidis ATCC 13076, S. enterica serova Typhimurium Korean isolate, Vibrio parahaemolyticus ATCC 17803, Escherichia coli O157:H7 ATCC 43894 and Pseudomonas aeruginosa KCTC 1637 at three different temperatures (4$^{\circ}C$, $25^{\circ}C$ and 36$^{\circ}C$) with or without an organic material (2% yeast extract), respectively. The antimicrobial activities showed over 4 log-reductions (1.0$\times$10$^4$CFU/ml reduction) against all pathogens reacted at 37$^{\circ}C$ for 3 hours in the absence of the organic material. The activities showed same results when GC-l00X was diluted with same volume of distilled water or standard hard water (CaCO$_3$300 ppm). Its antimicrobial activity was more effective and quicker in Gram-negative bacteria than Gram-positive bacteria. Its washing efficacy against E. coli O157:H7 exposed to the surfaces of tomatoes (grapes) was compared with that of the other sanitizers such as other kitchen synthetic detergent and 100-ppm chlorine water. For the toxicological evaluation of the sanitizers, viable counts of E. coli O157:H7 penetrated into the core of tomatoes after washing products were also compared. The result revealed that GC-100X stock solution and its 5% diluted solution had similar washing effects to 100-ppm chlorine water and more effective than the other kitchen synthetic detergent. This result indicated that GC- l00X had antimicrobial activity and no toxicological side effects, therefore, could be useful for a new sanitizer to use in flood safety and kitchen hygiene.

• Food Science of Animal Resources
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• v.26 no.1
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• pp.37-42
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• 2006

The current study was conducted to investigate the effect of types of crate and season on transport condition and mortality, and ultimately to identify the best practice for reducing economic lose. Total loading weight stocking density, transport and lairage times and mortality were surveyed from the management data sheet of two companies for each first week of January, April, August and October, An average loading weight, length of transport and lairage times and mortality were 3.9 ton, 96 min, 478 min and 0.6%, respectively. Mortality after lairage was not significant between two types of crate. In addition, container type crate showed higher loading weight and stocking density than box type one. Spring and winter had significantly higher mortality with 0.7 and 0.8%, respectively, then summer and fell of 0.5%. An interaction between crate type and season on mortality showed that mortality for box type on was higher in spring and winter with 0.8 and 0.7%, respectively, compared to summer and fall of 0,3 and 0.4% respectively. In the case of container type crate, spring, fall and winter had greatly different death into with 0.7, 0.5 and 0.8%, respectively, while there was no difference between spring and summer, and between summer and winter, Mortality after transportation was similar between both crate type, with higher rate for spring and winder than other seasons. The result was likely related to death of exposure due to extended waiting time without heating facility.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.1
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• pp.33-42
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• 2014

Purpose: I-131 scan using High Energy (HE) collimator is generally used. While, Medium Energy (ME) collimator is not suggested to use in result of an excessive septal penetration effects, it is used to improve the sensitivities of count rate on lower dose of I-131. This research aims to evaluate I-131 SPECT/CT image quality using by HE and ME collimator and also find out the possibility of ME collimator clinical application. Materials and Methods: ME and HE collimator are substituted as Siemens symbia T16 SPECT/CT, using I-131 point source and NEMA NU-2 IQ phantom. Single Energy Window (SEW) and Triple Energy Windows (TEW) are applied for image acquisition and images with CTAC and Scatter correction application or not, applied different number of iteration and sub set are reconstructed by IR method, flash 3D. By analysis of acquired image, the comparison on sensitivities, contrast, noise and aspect ratio of two collimators are able to be evaluated. Results: ME Collimator is ahead of HE collimator in terms of sensitivity (ME collimator: 188.18 cps/MBq, HE collimator: 46.31 cps/MBq). For contrast, reconstruction image used by HE collimator with TEW, 16 subset 8 iteration applied CTAC is shown the highest contrast (TCQI=190.64). In same condition, ME collimator has lower contrast than HE collimator (TCQI=66.05). The lowest aspect ratio for ME collimator and HE collimator are 1.065 with SEW, CTAC (+) and 1.024 with TEW, CTAC (+) respectively. Conclusion: Selecting a proper collimator is important factor for image quality. This research finding tells that HE collimator, which is generally used for I-131 scan emitted high energy ${\gamma}$-ray is the most recommendable collimator for image quality. However, ME collimator is also applicable in condition of lower dose, lower sensitive if utilizing energy window, matrix size, IR parameter, CTAC and scatter correction appropriately.

• Reproductive and Developmental Biology
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• v.31 no.3
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• pp.161-167
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• 2007

In this study, we constructed and tested retrovirus vectors designed to express the human thrombopoietin gene under the control of the tetracycline-inducible promoters. To increase the hTPO gene expression at him-on state, WPRE sequence was also introduced into retrovirus vector at downstream region of either the hTPO gene or the sequence encoding reverse tetracycline-controlled transactivator (rtTA). Primary culture cells (PFF, porcine fetal fibroblast; CEF, chicken embryonic fibroblast) infected with the recombinant retrovirus were cultured in the medium supplemented with or without doxycycline for 48hr, and induction efficiency was measured by comparing the hTPO gene expression level using RT-PCR, western blot and ELISA. Higher hPTO expression and tighter expression control were observed from the vector in which the WPRE sequence was placed at downstream of the hTPO (in CEF) or rtTA(in PFF) gene. This resulting tetracycline inducible vector system may be helpful in solving serious physiological disturbance problems which have been a major obstacle in successful production of transgenic animals.

• Korean Journal of Environmental Agriculture
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• v.36 no.2
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• pp.119-128
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• 2017

BACKGROUND: Miscellaneous cereal have been largely consumed in Korea as due to their physiological functions beneficial to human health. The cereals are currently a social concern because they have been found to contain heavy metals. Thus, monitoring heavy metals in the cereals is an important requirement for food safety analysis. In this study, we determined arsenic concentration in the cereals randomly harvested from different markets. METHODS AND RESULTS: Inorganic arsenic was determined by ICP-MS coupled with HPLC system. The HPLC-ICP-MS analysis was optimized based on the limit of detection and recover test to reach $0.13-1.24{\mu}g/kg$ and 94.3-102.1%, respectively. The concentrations of inorganic arsenic equivalent to daily exposure were levels of $19.91{\mu}g/day$ in mixed grain, $1.07{\mu}g/day$ in glutinous rice, $0.77{\mu}g/day$ in black brown rice, $0.13{\mu}g/day$ in barley and $0.11{\mu}g/day$ in soybeans. CONCLUSION: The levels of arsenic in miscellaneous cereals were found lower than the recommended The Joint FAO/WHO Expert Committee on Food Additives (JECFA) levels, suggesting that the cereals marketed in Korea are not potential concern in risk assessment.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.681-687
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• 2007

This study was designed to examine the suitable characteristics of potential probiotic bacteria. Possible probiotic bacteria, including Lactobacillus acidophilus DDS-1, Lb. acidophilus B-3208, Bifidobacterium bifidum KCTC 3357, Lb. plantarum, Leuconostoc mesenteroides ssp. mesenteroides ATCC 8293, and Lactococcus lactis ssp. lactis ATCC 7962 were selected. We then measured their acid and bile tolerances, adhesion properties in the gastrointestinal tract, antimicrobial activity against pathogenic bacteria, and immunomodulation activity. The acid tolerances of Lb. acidophilus DDS-1, Lb. acidophilus B-3208, Lb. plantarum, and Leu. mesenteroides ssp. mesenteroides ATCC 8293, in PBS (pH 2.5) for 2 hr, were high enough that 50% of the inocula survived. The bile tolerances of all bacteria, except Lc. lactis ssp. lactis ATCC 7962, were also observed at a 3% oxgall concentration in MRS broth. The results of the adhesion property assay showed that the total binding affinities of Lb. acidophilus DDS-1, Lb. acidophilus B-3208, and B. bifidum were about three times higher than those of the other bacteria. In testing their antimicrobial activities against pathogens, Lb. acidophilus B-3208, B. bifidum KCTC 3357, and Lb. plantarum inhibited the growth of pathogenic bacteria. For their immunomodulation activity, the cell wall fractions from Lb. acidophilus DDS-1 and Lb. acidophilus B-3208 showed the highest bone marrow cell proliferation activities. However, the cell wall fractions of Lb. acidophilus DDS-1 and B. bifidum, and the cytosol fraction of Lc. lactis ssp. lactis ATCC 7962 showed higher macrophage stimulation activities than those of the other bacteria. Since Lb. acidophilus DDS-1 and Lb. acidophilus B-3208 satisfy the requirements for probiotics, they can be considered suitable probiotic bacteria.

• Tuberculosis and Respiratory Diseases
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• v.55 no.5
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• pp.478-487
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• 2003

Background : There have been several studies showing that the angiotensin II and angiotensin converting enzyme(ACE) contributes to the apoptosis of alveolar epithelial cells in idiopathic interstitial pneumonia and the activation of fibroblasts during the process of pulmonary fibrosis. These results suggest that the pulmonary fibrosis can be inhibited by the angiotensin II receptor antagonist(AGIIRA). This study was performed to identify the therapeutic effect of AGIIRA in idiopathic pulmonary fibrosis(IPF). Method : Thirteen patients with IPF, who were diagnosed with an open lung biopsy(6 patients) and furfilling the ATS criteria(7 patients) between March 1999 and October 2001 at the Gachon medical center, were enrolled in this study. Of these patients, eight patients were treated with a regimen including AGIIRA(AT group), and five were treated without AGIIRA(NT group). The pulmonary function tests and dyspnea(ATS scale) were measured at diagnosis and 1 year after treatment. All the data was collected to analyze the therapeutic effect of AGIIRA on the patients with IPF. Results : The AT group contained 8 patients(M:F=4:4) and the NT group contained 5 patients(M:F=3:2). There was no significant difference in the serum angiotensin II level between the two groups($202.5{\pm}58.5$ vs $163.7{\pm}47.3pg/ml$, p>0.05). The AT group showed an upward trend in TLC(+3%), FVC(+4%), FEV1(+3%) and DLco(+2%) compared to the NT group(TLC(-14%), FVC(-3%), FEV1(-4%) except for DLco(+5%)). The dyspnea score in the AT group improved significantly but not in the NT group. Conclusion : These results suggest that the angiotensin II receptor antagonist may have an effect on stabilizing IPF.