• Molecules and Cells
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• v.20 no.3
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• pp.361-363
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• 2005

Plasmid Achromobacter secretion (PAS) factor is a putative secretion factor that induces the secretion of periplasmic proteins. PAS factor from Vibrio vulnificus was crystallized at 294 K by the hanging drop vapor-diffusion method. It was isolated as a monomer during the purification procedures. The native crystal belongs to the F222 space group with unit cell parameters a = 56.1, b = 74.4, $c=80.0{\AA}$, ${\alpha}={\beta}={\gamma}=90^{\circ}$. The crystal was soaked in cryoprotectant containing 1 M NaBr for 1 h for MAD phasing. The diffraction limit of the Br-MAD data set was $1.9{\AA}$ using synchrotron X-ray irradiation at beam line BL-18B at the Photon Factory, Japan.

• Corrosion Science and Technology
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• v.6 no.1
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• pp.18-23
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• 2007

DLC coatings have been deposited onto substrate of STS 316L and Ti alloy using r.f. PACVD (plasma-assisted chemical vapor deposition) with a mixture of $C_{6}H_{6}$ and $SiH_{4}$ as the process gases. Corrosion performance of DLC coatings was investigated by electrochemical techniques (potentiodynamic polarization test and electrochemical impedance spectroscopy) and surface analysis (scanning electron microscopy). The electrolyte used in this test was a 0.89% NaCl solution of pH 7.4 at temperature $37^{\circ}C$. The porosity and protective efficiency of DLC coatings were obtained using potentiodynamic polarization test. Moreover, the delamination area and volume fraction of water uptake of DLC coatings as a function of immersion time were calculated using electrochemical impedance spectroscopy. This study provides the reliable and quantitative data for assessment of the effect of substrate on corrosion performance of Si-DLC coatings. The results showed that Si-DLC coating on Ti alloy could improve corrosion resistance more than that on STS 316L in the simulated body fluid environment. This could be attributed to the formation of a dense and low-porosity coating, which impedes the penetration of water and ions.

• YAKHAK HOEJI
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• v.40 no.5
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• pp.558-562
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• 1996

Betulinic acid and alphitolic acid, the triterpenoids of Zyziphi Fructus, were isolated with silica gel column chromatography and used as the standard substances for the analysis. The compounds were determined with HPLC and HPTLC. They were separated on reversed phase column (Nova-Pak C18) with 0.05M Na2HPO4-methanol (19:81) in HPLC and detected at 210nm. Separation on HPTLC precoated silica gel F254 plates was carried out with chloroform-methanol (6:1) and the separated compounds were reacted with p-anisaldehyde and detected at 540nm. The contents of betulinic acid and alphitolic acid in Zyziphi Fructus from four different regions in Korea were in the range of 2.9~3.8% and 3.2~3.9%, respectively.

• Journal of Korean Society on Water Environment
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• v.18 no.2
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• pp.113-122
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• 2002

A bench-scale anoxic membrane bioreactor (MBR) system, consisting of a bioreactor coupled to a ceramic crossflow ultrafiltration module, was evaluated to treat a synthetic wastewater containing alkaline hydrolysis byproducts (hydrolysates) of RDX, The wastewater was formulated the same as RDX hydrolysates, and consisted of acetate, formate, formaldehyde as carbon sources and nitrite, nitrate as electron accepters. The MBR system removed 80 to 90% of these carbon sources, and approximately 90% of the stoichiometric amount of nitrate, 60% of nitrite. The reactor was also operated over a range of transmembrane pressures, temperatures, suspended solids concentration, and organic loading rate in order to maximize treatment efficiency and permeate flux. Increasing transmembrane pressure and temperature did not improve membrane flux significantly. Increasing biomass concentration in the bioreactor decreased the permeate flux significantly. The maximum volumetric organic loading rate was $0.72kg\;COD/m^3/day$, and the maximum F/M ratio was 0.50 kg N/kg MLSS/day and 1.82 kg COD/kg MLSS/day. Membrane permeate was clear and essentially free of bacteria, as indicated by heterotrophic plate count. Permeate flux ranged between 0.15 and $2.0m^3/m^2/day$ and was maintained by routine backwashing every 3 to 4 day. Backwashing with 2% NaOCl solution every fourth or fifth backwashing cycle was able to restore membrane flux to its original value.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.17-18
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• 2022

Carbon dioxide emissions in the construction sector account for 38% of all industries, and environmental destruction is occurring due to indiscriminate use of natural resources. The purpose of this study is to develop by-product aggregate Non-Sintered Cement(NSC) that can replace sand used as natural aggregate and Portland cement. Therefore, Ground Granulated Blast Furnace Slag, Type C Fly Ash and Type F Fly Ash are used to replace cement, and water granulated ferro-nickel slag(FNS) is used to replace aggregate. The flow, compressive strength and flexural strength of the formulation using sand as an aggregate and the formulation replacing 100% FNS were compared. As a result of the experiment, the formulation using FNS had higher overall strength than the formulation using sand, and as the substitution rate of Type C fly ash increased, the strength was the best. Formulation using FNS is more fluid than using sand. Through this study, we show the possibility of 100% substitution of FNS and its applicability to secondary concrete products of by-product aggregate NSC.

• Journal of Fisheries and Marine Sciences Education
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• v.23 no.3
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• pp.410-424
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• 2011

This study was investigated for the purpose of obtaining basic data which can be applied to processing of canned sea mussel using tomato paste. Shell were washed, and then steamed and shucked. Sea mussel meat was prepared with ratio of sea mussel 90g, tomato paste sauce 65g(tomato paste 42%, gum guar 1.0%, salt 2.0%, starch syrup 2.0%, cooking wine 1%, water 52%). The sea mussel meats were packed with vacuum seamer in 301-3 can, and then sterilized for various F0 value(F0 8-12 min.) in a steam system retort at $118^{\circ}C$. The factors such as pH, VBN, amino-N, total amino acid, free amino acid, chemical composition, color value (L, a, b), texture profile, TBA value, mineral, sensory evaluation and viable bacterial count of the canned sea mussel produced with various sterilization condition(F0 8-12 min.) were measured. The same element was also measured during preservation. The results showed that the product sterilized at F0 8 min. and preserved for 90 days were the most desirable.

• Journal of radiological science and technology
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• v.36 no.4
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• pp.291-297
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• 2013

This study is aimed to evaluate the effect of $T_{1/2}$ upon count rates in the analysis of dynamic scan using NaI (Tl) scintillation camera, and suggest a new quality control method with this effects. We producted a point source with $^{99m}TcO_4^-$ of 18.5 to 185 MBq in the 2 mL syringes, and acquired 30 frames of dynamic images with 10 to 60 seconds each using Infinia gamma camera (GE, USA). In the second experiment, 90 frames of dynamic images were acquired from 74 MBq point source by 5 gamma cameras (Infinia 2, Forte 2, Argus 1). There were not significant differences in average count rates of the sources with 18.5 to 92.5 MBq in the analysis of 10 to 60 seconds/frame with 10 seconds interval in the first experiment (p>0.05). But there were significantly low average count rates with the sources over 111 MBq activity at 60 seconds/frame (p<0.01). According to the second analysis results of linear regression by count rates of 5 gamma cameras those were acquired during 90 minutes, counting efficiency of fourth gamma camera was most low as 0.0064%, and gradient and coefficient of variation was high as 0.0042 and 0.229 each. We could not find abnormal fluctuation in $x^2$ test with count rates (p>0.02), and we could find the homogeneity of variance in Levene's F-test among the gamma cameras (p>0.05). At the correlation analysis, there was only correlation between counting efficiency and gradient as significant negative correlation (r=-0.90, p<0.05). Lastly, according to the results of calculation of $T_{1/2}$ error from change of gradient with -0.25% to +0.25%, if $T_{1/2}$ is relatively long, or gradient is high, the error increase relationally. When estimate the value of 4th camera which has highest gradient from the above mentioned result, we could not see $T_{1/2}$ error within 60 minutes at that value. In conclusion, it is necessary for the scintillation gamma camera in medical field to manage hard for the quality of radiation measurement. Especially, we found a tendency that count rate changes over time at this study, and we proved that it can effect $T_{1/2}$. And also, there is need of appropriate phantoms and the method of quality management like this study, because there are not any advice or limitation degrees for domestic medical purpose scintillation camera.

• The Korean Journal of Nuclear Medicine
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• v.30 no.3
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• pp.299-314
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• 1996

The purpose of the present study was to validate the use of tissue radioactivity ratios instead of regional metabolic rates for the assessment of regional metabolic changes in Alzheimer's disease(AD) with [$^{18}F$]FDG PET and to examine the correlation of ratio indices with the severity of cognitive impairment in AD. Thirty-seven AD Patients(age $68{\pm}9 yrs$, $mean{\pm}s.d.$; 36 probable and 1 definite AD), 28 patients with dementia of non-Alzheimer type(age $66{\pm}7 yrs$), and 17 healthy controls(age $66{\pm}4 yrs$) underwent [$^{18}F$]FDG PET imaging. Two simplified radioactivity ratio indices were calculated from 37-66 min image: region-to-cerebellar radioactivity ratio(RCR) and a composite radioactivity ratio(a ratio of radioactivity in the most typically affected regions over the least typically affected regions: CRR). Local cerebral metabolic rate for glucose(LCMRglu) was also measured using a three-compartment, five-parameter tracer kinetic model. The ratio indices were significantly lower in AD patients than in controls(RCR in temporoparietal cortex, $0.949{\pm}0.136$ vs. $1.238{\pm}0.129$, p=0.0004; RCR in frontal cortex, $1.027{\pm}0.128$ vs. $1.361{\pm}0.151$, p<0.0001; CRR, $0.886{\pm}0.096$ vs. $1.032{\pm}0.042$. p=0.0024). On the RCR analysis, 86% of AD patients showed a pattern of bilateral temporoparietal hypometabolism with or without frontal involvement; hypometabolism was unilateral in 11% of the patients. When bilateral temporoparietal hypometabolism was considered to be suggestive of AD, the sensitivity and specificity of the RCR analysis for the differential diagnosis of AD were 86% and 73%, respectively. The RCR was correlated significantly with the macroparameter K [$K_1k_3/(k_2+k_3)$] (r=0.775, p<0.0001) and LCMRglu(r=0.633, p=0.0002) measured using the kinetic model. In patients with AD, both average RCR of cortical association areas and CRR were correlated with Mini-Mental Status Examination(r=0.565, p=0.0145; r=0.642, p=0.0031, respectively), Clinical Dementia Rating(r=-0.576, p=0.0124; r=-0.591, p=0.0077), and total score of Mattis Dementia Rating Scale (r=0.574, p=0.0648; r=0.737, p=0.0096). There were also significant correlations between memory and language impairments and corresponding regional RCRs. The results suggest that the [$^{18}F$]FDG PET ratio indices, RCR and CRR, reflect global and regional metabolic rates and correlate with the severity of cognitive impairment in AD. The simplified ratio analysis may be clinically useful for the differential diagnosis and serial monitoring of the disease.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.1
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• pp.16-21
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• 2007

Purpose: We evaluated the diagnostic value of $^{18}F-FDG$ PET/CT (PET/CT) in lymph node staging of non-small cell lung cancer (NSCLC) considering calcification and histologic types as well as FDG uptake. Materials and Methods: Fifty-three patients (38 men, 15 women; mean age, 62 years) with NSCLC underwent surgical resection (tumor resection and lymph node dissection) after PET/CT. After surgery, we compared PET/CT results with the biopsy results, and analyzed lymph node metastases, based on histologic types. PET diagnosis of lymph node metastasis was determined by maximum SUV (maxSUV) > 3.0, and PET/CT diagnosis was determined by maxSUV > 3.0 without lymph node calcification. Results: By PET diagnosis, the sensitivity, specificity, and accuracy of overall lymph node staging were 45% (13 of 29), 91% (228 of 252), and 86% (241 of 281). Specificity was 91% in both squamous cell carcinoma and adenocarcinoma, while sensitivity was 71% in squamous cell carcinoma and 36% in adenocarcinoma. When we excluded calcified lymph node with maxSUV > 3.0 from metastasis by PET/CT diagnosis, specificity improved to 98% in squamous cell carcinoma and 97% in adenocarcinoma. The degree of improvement was not dependent on histologic types. Conclusion: PET/CT improved specificity of lymph node staging by reducing false positive lymph node regardless of histologic types of NSCLC.

• Economic and Environmental Geology
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• v.27 no.4
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• pp.375-385
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• 1994

The studied area is composed of Precambrian gneiss complex, middle Jurassic biotite granite, late Cretaceour sediments, volcanics and pink feldspar granite. Characteristic minerals of the biotite granite is plagioclase and hornblende whereas the pink feldspar granite is pink feldspar (perthite) and quartz. Plagioclase compositions of the biotite granite and the pink feldspar granite are oligoclase to calcic andesine ($An_{18-44}$) and sodic albite ($An_{0.5-5.0}$), respectively. In the variation diagrams of the Harker and normative Q-Or-Pl diagram, the biotite granite belongs to the category from granodiorite to granite, the pink feldspar granite from nomal to late granite. The values of D.I. L.I. and alkalinity of the pink feldspar granite are higher than those of the biotite granite. While CaO is enriched in the biotite granite, $K_2O$ is enriched in the pink feldspar granite. The ratio of $K_2O/Na_2O$ which indicates the relative ratio of alkali is 1.06 in the pink feldspar granite, and 0.86 in the biotite granite. In A-M-F and N-C-K diagrams both these granites are plotted in peraluminus granite ($Al_2O_3$>$Na_2O+K_2O+CaO$) region, assigned to calc alkaline series and alkaline series respectively. Put into the form of A-C-F diagram, the biotite granite falls under I-type, and the pink feldspar granite S-type. On the base of whole rock ratios of $Fe^{+3}/Fe^{+2}+Fe^{+3}$ and $^{87}Sr/^{86}Sr$ for the granites in studied area, the biotite granite indicates ilmenite series (0.26) and S-type and/or contaminated I-type ($0.72020{\pm}0.00050$), the pink feldspar granite magnetite series (0.44) and I-type ($0.70826{\pm}0.00020$).