• Investigative Magnetic Resonance Imaging
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• v.12 no.2
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• pp.100-106
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• 2008

The purpose of this study was to confirm the exactitude of in vitro nuclear magnetic resonance spectroscopy(NMRS) and to complement the defect of in vivo NMRS. It has been difficult to understand the metabolism of a cerebellum using in vivo NMRS owing to the generated inhomogeneity of magnetic fields (B0 and B1 field) by the complexity of the cerebellum structure. Thus, this study tried to more exactly analyze the metabolism of a canine cerebellum using the cell extraction and high resolution NMRS. In order to conduct the absolute metabolic quantification in a canine cerebellum, the spectrum of our phantom included in various brain metabolites (i.e., NAA, Cr, Cho, Ins, Lac, GABA, Glu, Gln, Tau and Ala) was obtained. The canine cerebellum tissue was extracted using the methanol-chloroform water extraction (M/C extraction) and one group was filtered and the other group was not under extract processing. Finally, NMRS of a phantom solution and two extract solution (90% D2O) was progressed using a 500MHz (11.4 T) NMR machine. Filtering a solution of the tissue extract increased the signal to noise ratio (SNR). The metabolic concentrations of a canine cerebellum were more close to rat’s metabolic concentration than human’s metabolic concentration. The present study demonstrates the absolute quantification technique in vitro high resolution NMRS with tissue extraction as the method to accurately measure metabolite concentration.

• KSBB Journal
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• v.29 no.4
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• pp.285-296
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• 2014

Although the problems of the algal blooms have been world-widely observed in freshwater, estuary, and marine throughout the year, it is not yet certain what are the basic causes of such blooms. Consequently, it is very difficult to predict when and where algal blooms occur. The constituents of the Asian dust are in a good agreement with the elements required for the algal growth, which suggests some possible relationship between the algal blooms and the Asian dust. There have been frequently algal blooms in drinking water from rivers or lakes. However, there is no any algal blooms in upwelling waters where the Asian dust cannot penetrate into the soil due to its relatively weak settling velocity (size of particles, $4.5{\pm}1.5{\mu}m$), which implies the possible close relationship of the Asian dust with algal blooms. The present initiative study is thus intended firstly in Korea to illustrate such a relationship by reviewing typical previous studies along with 12 years of weekly iron profiles (2001~2012) and two slant culture experiments with the dissolved Asian dust. The result showed bacterial suspected colonies in the slant culture experiment that are qualitatively in a good agreement with the recent Japanese studies. Since the diatoms require cheap energy (8%) compared to other phytoplankton (100%) to synthesize their cell walls by silicate, the present results can be used to predict algal blooms by diatoms if the concentrations of iron and silicate are available during spring and fall. It can be postulated that the algal blooms occur only if the environmental factors such as light, nutrients, calm water surface layer, temperature, and pH are simultaneously satisfied with the requirements of the micronutrients of mineral ions supplied by the Asian dust as enzymatic cofactors for the rapid bio-synthesis of the macromolecules during algal blooms. Simple eco-friendly methods to regulate the algal blooms are suggested for the initial stage of blooming with limited area: 1) to cover up the water surface with black curtain and inhibit photosynthesis during the day time, 2) to blow air (20.9%) or pure oxygen into the bottom of the water and inhibit rubisco for carbon uptake and nitrate reductase for nitrogen uptake activities in algal growth during the night, 3) to eliminate the resting spores or cysts by suction of bottom sediments as deep as 5 cm to prevent the next year germinations.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.255-262
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• 2002

This experiment was performed to improve the stability of Lactobacillus fermentum YL-3 as a poultry probiotics. The culture conditions that improve acid tolerance of L. fermentum YL-3 were investigated by changing several factors such as medium composition, temperature, anaerobic incubation and culture time. Also, L. fermentum YL-3 was encapsulated with alginate, calcium chloride and chitosan. The stable culture conditions of L. fermentum YL-3 were obtained in anaerobic incubation using MRS media without tween 80 for 20 hour at $42^{\circ}C$. The capsule after treatment with 1% chitosan was formed close membrane by a bridge bond. Immobilization of L. fermentum YL-3 in capsule was observed by confocal laser scanning microscopy, and cell viability was $2.0{\times}10^9\;CFU/g$ above the average. L. fermentum YL-3 capsule after acid treated at pH 2.0 for 3 hour survived about 40%, but those encapsulated with 1% chitosan survived about 65%. Survival rate of capsule stored at room temperature decreased about $2{\sim}3$ log cycle during 3 weeks, but viability of capsule stored at $4^{\circ}C$ during 3 weeks maintained almost $10^8\;CFU/g$ levels.

• Journal of the Korean Chemical Society
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• v.32 no.6
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• pp.520-527
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• 1988

The crystal structures of $Co^{2+}\;and\;Ag^+\;exchanged\;zeolite\; A,\; Ag_6Co_3$-A(a = 12.131(5)$\AA$) and $Ag_3Co_{4.5}$-A(a = 12.145(1)$\AA$), have been determined by single crystal X-ray diffraction techniques. Both structures were solved and refined in the cubic space group Pm3m at 21(1)$^{\circ}C$. Full-matrix leastsquares refinement converged to the final error indices of R1 = 0.045 and R2 = 0.041 for $Ag_3Co_{4.5}-A,\; and\; R1 = 0.066\; and\; R2 = 0.076\; for\; Ag_6Co_3$-A using the 258 and 189 reflections, respectively, for which I > 3$\sigma$(I). Both structures indicate that CO(Ⅱ)ions are coordinated by three framework oxygens; the Co(II) to O(3) distances are 2.118(4)$\AA$ for $Ag_3Co_{4.5}$-A and 2.106(1)$\AA$ for $Ag_6Co_3-A$, respectively. In each structure, the angle substended at Co(II), O(3)-Co(II)-O(3) is ca 120°, close to the idealized trigonalplanar value. $Co^{2+}$ ions prefer to 6-ring sites and $Ag^+$ ions prefer to 8-ring site when total number of cations is more than 8. The crystals of hydrated and dehydrated $Ag_{12-2x}Co_x-A (x > 4.5)$ had no crystalline diffraction pattern, indicating the apparent exchange limit of $Co^{2+}\; into\; Ag_{12}-A\; is\; 4.5 Co^{2+}$ ions per unit cell. $Co^{2+}$ ions hydrolyze $H_2O$ molecules and $H_3O^+$ concentraction is accumulating. These $H_3O^+$ ions destroy the zeolite structures.

• Radiation Oncology Journal
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• v.24 no.3
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• pp.164-170
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• 2006

[ $\underline{Purpose}$ ]: This study identified the result of postoperative radiation therapy and the prognostic factors to affect survival rates in cancer patients. $\underline{Materials\;and\;Methods}$: One hundred and thirty three patients with cervical cancer who were treated with postoperative radiation therapy following surgery at our institution between June 1985 and November 2002 were retrospectively analyzed. One hundred and thirteen patients had stage IB disease, and 20 patients had stage IIA disease. Histological examination revealed 118 squamous cell carcinoma patients and 15 adenocarcinoma patients. Sixty seven patients were noted to have stromal invasion greater than 10 mm, and 45 patients were noted to have stromal Invasion 10 mm or less. Positive lymphovascular invasion was found in 24 patients, and positive pelvic lymph nodes were noted in 39 patients. Positive vaginal resection margin was documented in 8 patients. All of the patients were treated with external beam radiation therapy to encompass whole pelvis and primary surgical tumor bed. Intracavitary radiation therapy was added to 19 patients who had positive or close surgical margins. $\underline{Results}$: Actuarial overall and disease-free survival rates for entire group of the patients were 88% and 84% at 5 years, respectively. Five-year disease-free survival rates for patients with stromal invasion greater than 10 mm and 10 mm or less were 76% and 97%, respectively (p<0.05). Also there was a significantly lower survival in patients with positive pelvic lymph nodes compared with patients with negative pelvic lymph nodes (p<0.05). However, lymphovascular invasion, positive vaginal resection margins were not statistically significant prognostic factors. Addition of neoadjuvant chemotherapy or type of surgery did not affect disease-free survival. $\underline{Conclusion}$: Postoperative radiation therapy appears to achieve satisfactory local control with limited morbidity in cervical cancer patients with high pathologic risk factors. Distant metastasis was a dominant failure pattern to affect survival in cervical cancer patients after radical surgery and radiation and more effective systemic treatment should be investigated in these high-risk patients.

• Journal of the Korean Magnetics Society
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• v.17 no.1
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• pp.18-21
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• 2007

The hexagonal $HoMn_{1-x}-Fe_xO_3$(x=0.00, 0.05) thin films were prepared using pulsed laser deposition(PLD) method on $Pt/Ti/SiO_2/Si$ substrate. The microstructure and magnetic properties have been studied by x-ray diffraction(XRD), atomic force microscopy (AFH), scanning electron microscope(SEM:), x-ray photoelectron spectroscopy(XPS), and conversion electron $M\"{o}ssbauer$ spectroscopy(CEMS). From the analysis of the x-ray diffraction patterns, the crystal structure for all films was found to be a hexagonal($P6_3cm$), which was preferentially grown along(110) direction. The lattice constant $c_0$ of the film with x=0.05 was close to that of single crystal, whereas lattice constant $a_0$ with respect to single crystal shows a slight decrease. This difference of lattice parameters between film and single crystal was caused by the lattice mismatch between the film and $Pt/Ti/SiO_2/Si$ substrate. Conversion electron $M\"{o}ssbauer$ spectrum of $HoMn_{0.95}Fe_{0.05}O_3$ thin film shows an asymmetry doublet absorption ratio at room temperature, which is due to the oriented direction of crystallographic domains. This is corresponding with analysis of x-ray diffraction. The quadrupole splitting(${\Delta}E_Q$) at room temperature is found to be $1.62{\pm}0.01mm/s$. This large ${\Delta}E_Q$ was caused by asymmetry environment surrounding Fe ion.

• Journal of Radiation Protection and Research
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• v.18 no.2
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• pp.1-16
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• 1993

As guides to decision-making in the management of the victims in case of acute whole body or partial body radiation exposure, we studied the relationship between radiation dose and the frequency of chromosomal aberrations observed in peripheral lymphocytes that were irradiated in vitro with $^{60}Co\;{\gamma}-rays$ at doses ranging from 2Gy to 12Gy. The yields of cells with unstable chromosomal aberrations (dicentric chromosomes, ring chromosomes, and acentric fragment pairs) were 32% at 2Gy, 47% at 4Gy, 80% at 6Gy, 94% at 8Gy, and 100% at 10Gy and over. Ydr, which reflect average dose to the whole body in case of acute whole body exposure, were 1.373 at 2Gy, 0.669 at 4Gy, 1.734 at 6Gy, 2.773 at 8Gy, 3.746 at 10Gy and 5.454 at 12Gy. The relationship between radiation dose (D) and the frequency of dicentric plus ring chromosomes per cell(Ydr) could be expressed as $Ydr=9.322{\times}10^{-2}/Gy {\times}D+2.975{\times}10^{-2}/Gy^2{\times}D^2$. Qdr, which are used in estimating dose of partial body exposure and dose of past exposure, were 1.166 at 2Gy, 1.436 at 4Gy, 2.173 at 6Gy, 2.945 at 8Gy, 3.746 at 10Gy and 5.454 at 12Gy. To see how confidently this dosimetry system may be used, we obtained Qdr values from those who received one fraction of homogenous partial body irradiation of 1.BGy, 2.5Gy, and 7.OGy therapeutically; in vivo Qdr values were 1.109, 1.222 and 2.222 respectively. The estimated doses calculated from these in vivo Qdr values using the equation $Qdr=Ydr/(1- e^{-Ydr})$ were 1.52Gy, 2.48Gy, and 6.54Gy respectively, which were very close to the doses actually given.

• Korean Journal of Ecology and Environment
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• v.54 no.4
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• pp.303-314
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• 2021

To understand how to efficiently observe the biomass and community of phytoplankton, phytoplankton sampling was carried out from June to October 2019 at the Yeongju dam sediment control reservoir(YJ) and Bohyeonsan dam reservoir(BH1 and BH2). The results derived from microscopic observation, such as the conventional phytoplankton qualitative/quantitative analysis, and from the CHEMTAX method based on the pigments, were compared. The relative contribution of phytoplankton, calculated by the microscopy and CHEMTAX methods, showed a significant difference in all four classes: cryptophyta, chlorophyta, cyanobacteria, and diatoms. In addition, the correlation between the two observation methods was poor. This might be caused by methodological differences in microscopy that do not consider the varying cell sizes among phytoplankton species. In this study, by converting the cells into carbon, the slope between both carbon biomasses based on microscopy and CHEMTAX was improved close to the 1 : 1 line, and the y-intercept was closer to 0 for cryptophyta and diatoms. For cyanobacteria, the slope increased, the y-intercept decreased, and the plot approached 1 : 1 although the correlation coefficients were not improved in all classes. The present study suggests that application of CHEMTAX based on pigment analysis could be a possible approach to efficiently determine the relative carbon proportions of individual classes of phytoplankton community composition.

• Tuberculosis and Respiratory Diseases
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• v.44 no.2
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• pp.360-378
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• 1997

Background : Severe acute lung injury(ALI), also known as the adult respiratory distress syndrome(ARDS), is a heterogenous nature of dynamic and explosive clinical synrome that exacts a mortality of approximately 50%. Endotoxin(ETX) is an abundant component of the outer membrane of gram-negative bacteria capable of inducing severe lung injury in gram-negative sepsis and gram-negative bacterial pneumonia, which are among the most common predisposing causes of ARDS. The influx of PMNs into airway tissue is a pathological hallmark of LPS-induced lung injury. And there is a substantial evidence suggesting that cytokines are important mediators of lung injury in gram-negative sepsis. However, the kinetics of phagocytes and cytokines by an exact time sequence and their respective pathogenic importance remain to be elucidated. This study was performed to investigate the role of phagocytes and proinflammatory cytokines in ETX-induced ALI through a time course of changes in the concentration of protein, $TNF{\alpha}$ and IL-6, and counts of total and its differential cells in BALF. The consecutive histologic findings were also evaluated. Method : The experimental animals, healthy male Sprague-Dawley, weighted $200{\pm}50g$, were divided into control- and ALI- group. ALI was induced by an intravenous administration of ETX, 5mg/kg. Above mentioned all parameters were examined at 0(control), 3, 6, 24, 72 h after administration of ETX. $TNF{\alpha}$ and IL-6 cone. in BALF were measured by a bioassay. Results : The protein concentration and total leukocyte count(TC) in BALF was significantly increased at 3h compared to controls(p < 0.05). The protein conc. was significantly elavated during observation period, but TC was significantly decreased at 72h(p < 0.05 vs. 24h). There was a close relationship between TC and protein cone. in BALF(r = 0.65, p < 0.001). The PMN and monocyte count was well correlated with TC in BALF, and the correlation of PMN(r = 0.97, p < 0.001) appeared to be more meaningful than that of monocyte(r = 0.61, p < 0.001). There was also a significant correlation between protein cone. and PMN or monocyte count in BALF(PMN vs. monocyte : r = 0.55, p < 0.005 vs. r = 0.64, p < 0.001). The count of monocyte was significantly elavated during observation period though a meaningful reduction of PMN count in BALF at 72h, this observation suggested that monocyte may, at least, partipate in the process of lung injury steadly. In this study, there was no relationship between IL-6 and $TNF{\alpha}$ cone., and $TNF{\alpha}$ but not IL-6 was correlated with TC(r = 0.61, p < 0.05) and monocyte(r = 0.67, p < 0.05) in BALF only at 3, 6h after ETX introduced. In particular, the IL-6 cone. increased earlier and rapidly peaked than $TNF{\alpha}$ cone. in BALF. In histologic findings, the cell counts of lung slices were increased from 3 to 72h(p < 0.001 vs. NC). Alveolar wall-thickness was increased from 6 to 24h(p < 0.001 vs. NC). There was a significant correlation between the cell counts of lung slices and alveolar wall-thickness(r= 0.61, p < 0.001). This result suggested that the cellular infiltrations might be followed by the alterations of interstitium, and the edematous change of alveolar wall might be most rapidly recovered to its normal condition in the process of repair. Conclusion : We concluded that although the role of PMN is partly certain in ETX-induced ALI, it is somewhat inadequate to its known major impact on ALL Alveolar macrophage and/or non-immune cells such as pulmonary endothelial or epithelial cells, may be more importantly contributed to the initiation and perpetual progression of ETX-induced ALI. The IL-6 in ETX-induced ALI was independent to $TNF{\alpha}$, measured by a bioassay in BALF. The early rise in IL-6 in BALF implies multiple origins of the IL-6.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.1
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• pp.1-9
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• 2006

Regardless of the recent observed warmer winters in Korea, more freeze injuries and associated economic losses are reported in fruit industry than ever before. Existing freeze-frost forecasting systems employ only daily minimum temperature for judging the potential damage on dormant flowering buds but cannot accommodate potential biological responses such as short-term acclimation of plants to severe weather episodes as well as annual variation in climate. We introduce 'dormancy depth', in addition to daily minimum temperature, as a complementary criterion for judging the potential damage of freezing temperatures on dormant flowering buds of grape vines. Dormancy depth can be estimated by a phonology model driven by daily maximum and minimum temperature and is expected to make a reasonable proxy for physiological tolerance of buds to low temperature. Dormancy depth at a selected site was estimated for a climatological normal year by this model, and we found a close similarity in time course change pattern between the estimated dormancy depth and the known cold tolerance of fruit trees. Inter-annual and spatial variation in dormancy depth were identified by this method, showing the feasibility of using dormancy depth as a proxy indicator for tolerance to low temperature during the winter season. The model was applied to 10 vineyards which were recently damaged by a cold spell, and a temperature-dormancy depth-freeze injury relationship was formulated into an exponential-saturation model which can be used for judging freeze risk under a given set of temperature and dormancy depth. Based on this model and the expected lowest temperature with a 10-year recurrence interval, a freeze risk probability map was produced for Hwaseong County, Korea. The results seemed to explain why the vineyards in the warmer part of Hwaseong County have been hit by more freeBe damage than those in the cooler part of the county. A dormancy depth-minimum temperature dual engine freeze warning system was designed for vineyards in major production counties in Korea by combining the site-specific dormancy depth and minimum temperature forecasts with the freeze risk model. In this system, daily accumulation of thermal time since last fall leads to the dormancy state (depth) for today. The regional minimum temperature forecast for tomorrow by the Korea Meteorological Administration is converted to the site specific forecast at a 30m resolution. These data are input to the freeze risk model and the percent damage probability is calculated for each grid cell and mapped for the entire county. Similar approaches may be used to develop freeze warning systems for other deciduous fruit trees.