• Economic and Environmental Geology
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• v.44 no.4
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• pp.313-320
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• 2011

The Taebaegsan Mineralized District is the most prospective region for the useful mineral commodities such as a coal, non-metallic, metallic mineral in South Korea. From a general point of view, Cambro- Ordovician limestone formations, Myobong slate and Pungchon (Daegi) limestone, are the most fertilizable formations in the Taebaegsan Mineralized District. The geology around Weondong mine area consists mainly of Carboniferous-Triassic formations and Cambro-Ordovician formations intruded by rhyolite/quartz porphyry. The great overthrusted fault of N40~$50^{\circ}E$ direction, so called Weondong overthrust fault, is observed in the central part of the mine area and the NS fault system cuts the overthrusted fault. By postulating from the favorable geological and structural condition around Weondong area, the possibility of deep seated hidden ore bodies is expected. In 2010, on the basis of the results of LOTEM and CSAMT survey, the cross-hole survey was performed for the investigation of the hidden polymetallic ore body in the deep parts of the Weondong mine area and the grade of the newly-discovered orebody is as follows; (1) The cut-off grade for lead-zinc 3%; an weighted average grade 5.50% (2.7 m), (2) The cutoff grade for copper 0.1%; an weighted average grade 0.91% (14.65 m), (3) The cut-off grade for iron 30%; an weighted average grade 38.18% (3.3 m), (4) $WO_3$ for each cut-off grade(0.01%, 0.05%, 0.1%); an weighted average grade 0.29 wt. % (8.8 m), 1.15 wt. % (2.1 m), 1.97 wt. % (1.2 m), (5) $MoS_2$ for each cut-off grade(0.01%, 0.1%); an weighted average grade 0.15 wt. % (6.3S m), 0.28 wt. % (3.15 m), (6) $Ta_2O_5$ for each cut-off grade (0.01%, 0.1%); an weighted average grade 0.13% (19.S m), 1.11% (1.8 m), (7) $Nb_2O_5$ for each cut-offgrade (0.01%, 0.1%); an weighted average grade 0.06% 11.5 m), 0.15% (3.0 m).

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.6
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• pp.60-74
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• 2018

This study was to investigate the pedestrian's thermal environments in the North Sidewalk of E-W Street during summer heatwave. We carried out detailed measurements with four human-biometeorological stations on Dongjin Street, Jinju, Korea ($N35^{\circ}10.73{\sim}10.75^{\prime}$, $E128^{\circ}55.90{\sim}58.00^{\prime}$, elevation: 50m). Two of the stations stood under one row street tree and hedge(One-Tree), two row street tree and hedge (Two-Tree), one of the stations stood under shelter and awning(Shelter), while the other in the sun (Sunlit). The measurement spots were instrumented with microclimate monitoring stations to continuously measure microclimate, radiation from the six cardinal directions at the height of 1.1m so as to calculate the Universal Thermal Climate Index (UTCI) from 24th July to 21th August 2018. The radiant temperature of sidewalk's elements were measured by the reflective sphere and thermal camera at 29th July 2018. The analysis results of 9 day's 1 minute term human-biometeorological data absorbed by a man in standing position from 10am to 4pm, and 1 day's radiant temperature of sidewalk elements from 1:16pm to 1:35pm, showed the following. The shading of street tree and shelter were mitigated heat stress by the lowered UTCI at mid and late summer's daytime, One-Tree and Two-Tree lowered respectively 0.4~0.5 level, 0.5~0.8 level of the heat stress, Shelter lowered respectively 0.3~1.0 level of the heat stress compared with those in the Sunlit. But the thermal environments in the One-Tree, Two-Tree and Shelter during the heat wave supposed to user "very strong heat stress" while those in the Sunlit supposed to user "very strong heat stres" and "exterme heat stress". The main heat load temperature compared with body temperature ($37^{\circ}C$) were respectively $7.4^{\circ}C{\sim}21.4^{\circ}C$ (pavement), $14.7^{\circ}C{\sim}15.8^{\circ}C$ (road), $12.7^{\circ}C$ (shelter canopy), $7.0^{\circ}C$ (street funiture), $3.5^{\circ}C{\sim}6.4^{\circ}C$ (building facade). The main heat load percentage were respectively 34.9%~81.0% (pavement), 9.6%~25.2% (road), 24.8% (shelter canopy), 14.1%~15.4% (building facade), 5.7% (street facility). Reducing the radiant temperature of the pavement, road, building surfaces by shading is the most effective means to achieve outdoor thermal comfort for pedestrians in sidewalk. Therefore, increasing the projected canopy area and LAI of street tree through the minimal training and pruning, building dense roadside hedge are essential for pedestrians thermal comfort. In addition, thermal liner, high reflective materials, greening etc. should be introduced for reducing the surface temperature of shelter and awning canopy. Also, retro-reflective materials of building facade should be introduced for the control of reflective sun radiation. More aggressively pavement watering should be introduced for reducing the surface temperature of sidewalk's pavement.

• Journal of Korean Society for Atmospheric Environment
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• v.10 no.E
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• pp.311-324
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• 1994

The quantitative knowledge of N $O_{\gamma}$ (＝N $O_{x}$ ＋HN $O_3$＋/PAN＋N $O_3$ ＋$N_2$ $O_{5}$ ＋HN $O_2$＋N $O_3$$^{-10}$ ＋organic nitrates＋......)distribution is essential in tropospheric chemistry, especially, especially that related to understanding the processes leading to ozone production. Ambient concentrations of NO, N $O_2$, HN $O_3$ and PAN as well as total N $O_{\gamma}$ were measured during June and early July 1992 at a rural site(Candor, NC), in the central Piedmont region of NC. The measurements of N $O_{\gamma}$ species were made in an effort to provide a comprehensive understanding of nitrogen chemistry and to investigate the total nitrogen budget at the site. N $O_{\gamma}$, N $O_2$, and NO showed diurnal variations with maxima in the morning. The maximum N $O_{\gamma}$ concentration reached was 14.5 ppbv, and the maximum concentrations of NO and N $O_2$ were 5.4 and 7.8 PPbv, respectively. The mean N $O_{\gamma}$ concentration as found to be 2.88$\pm$1.58 ppbv(n=743). The mean concentrations of NO and N $O_2$, were found to be 0.15 $\pm$ 0.29 ppbv(n＝785) and 1.31 $\pm$ 0.99 ppbv(n＝769). Products of photochemical oxidants, (N <$O_{\gamma}$-N $O_{x}$ ), such as HN $O_3$ and PAN, as well as ozone showed diurnal variation with maxima in the afternoon and minima at night The fractions of individual reactive nitrogen species to total N $O_{\gamma}$ were investigated and contrasted to the results from remote marine site and rural continental sites. N $O_{x}$ was the major species to total N $O_{\gamma}$(45%). NO concentrations appeared to be nearly constant whether the Prevailing winds were from continental areas or from oceanic areas. Linear regression of $O_3$ with (N $O_{\gamma}$- N $O_{x}$ )/N $O_{\gamma}$ (i.e. percent N $O_{x}$ converted to the photochemical products of N $O_{\gamma}$) yielded ( $O_3$) ＝25.8 〔 N $O_{\gamma}$-N $O_{x}$ 〕/(N $O_{\gamma}$) ＋27, ( $r^{2}$＝0.58). The regression intercept is interpreted as the ozone back ground (intercept=27ppbv) and the slope suggests that 8.6 molecules of ozone are formed per molecule of N $O_{x}$ oxidized products (when the average N $O_{\gamma}$ concentration, about 3 ppbv at the site, is used). The N $O_{x}$ N $O_{\gamma}$ ratio was used as an indicator of the chemical age of airmasses and the ratio showed strong positive correlations with HN $O_3$( $r^{2}$=0.58), PAN ( $r^{2}$=0.46) and $O_3$( $r^{2}$=0.62). Larger N $O_{\gamma}$ and N $O_{x}$ N $O_{\gamma}$ ratio were found when winds came from continental sides. It may suggest that synoptic meteorological conditions and transport of N $O_{x}$ are important in the distribution of N $O_{\gamma}$ and its relationship with photochemical oxidants at the site.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.2
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• pp.230-240
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• 2016

Information on the effects of different yeast species on ruminal fermentation is limited. This experiment was conducted in a $3{\times}4$ factorial arrangement to explore and compare the effects of addition of three different live yeast species (Candida utilis 1314, Saccharomyces cerevisiae 1355, and Candida tropicalis 1254) at four doses (0, $0.25{\times}10^7$, $0.50{\times}10^7$, and $0.75{\times}10^7$ colony-forming unit [cfu]) on in vitro gas production kinetics, fiber degradation, methane production and ruminal fermentation characteristics of maize stover, and rice straw by mixed rumen microorganisms in dairy cows. The maximum gas production (Vf), dry matter disappearance (IVDMD), neutral detergent fiber disappearance (IVNDFD), and methane production in C. utilis group were less (p<0.01) than other two live yeast supplemented groups. The inclusion of S. cerevisiae reduced (p<0.01) the concentrations of ammonia nitrogen ($NH_3$-N), isobutyrate, and isovalerate compared to the other two yeast groups. C. tropicalis addition generally enhanced (p<0.05) IVDMD and IVNDFD. The $NH_3$-N concentration and $CH_4$ production were increased (p<0.05) by the addition of S. cerevisiae and C. tropicalis compared with the control. Supplementation of three yeast species decreased (p<0.05) or numerically decreased the ratio of acetate to propionate. The current results indicate that C. tropicalis is more preferred as yeast culture supplements, and its optimal dose should be $0.25{\times}10^7$ cfu/500 mg substrates in vitro.

• Restorative Dentistry and Endodontics
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• v.8 no.1
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• pp.89-96
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• 1982

The purpose of this study is to identify the phases of four different types, low-copper lathe cut (Type II, class 1) and spherical (Type II, class 2) amalgam alloys which are made by Caulk company and high copper Dispersalloy (Type II, class 3) made by Johnson & Johnson and Tytin (Type I, class 2) made by S.S. White and to determine the Vickers hardness number on the individual phase and four different types of dental amalgam. After each amalgam alloy and Hg measured exactly by the balance was triturated by the mechanical amalgamator (De Trey), the triturated mass was inserted into the cylindrical metal mold which was 4 mm in diameter and 12mm in height and was pressed by the Instron Universal Testing machine (Model 1125) at the speed of 1mm/minute with 143$kg/cm^2$ according to the A.D.A. Specification No. 1. The Specimen removed from the mold, mounted and stored in the room temperature for 7 days. The speciman was polished with the emery paper from #220 to #1200 and finally on the polishing cloth with 0.3 and 0.05 um $Al_2O_3$ powder suspended in water. And then each specimen was etched by Allan's method and washed with Sodium Bisulfinite for 30 seconds. Finally differentiation and metallography on each phase were obtained by using metallographical microscope (Versamet, Union) and microhardness was obtained by using microhardness tester (MVH-2, Torsee). The results were as follows: 1. In the low-copper amalgam, the ${\gamma}$, ${\gamma}_1$ and ${\gamma}_2$ phase were observed and in the high-copper amalgam, the ${\gamma}$, ${\gamma}_1$. ${\epsilon}$ and ${\eta}$ phases were observed but ${\gamma}_2$ phase was not observed. 2. Among the microhardness of each amalgam phase measured under pressing a vickers diamond indenter with 2.0gm load for 30 seconds, e phase has the highest V.H.N (314 ${\pm}$ 20), and in low-copper amalgam 12 phase has the lowest V.H.N. (29${\pm}$1) and ${\eta}$ phase which was observed in high-copper amalgam has 230${\pm}$13 V.H.N and this phase is considerd to contribute to strengthen the handness in amalgam. 3. The V.H.N. measured under pressing a Vickers diamond indenter with 300.0gm load for 30 seconds in low-copper amalgam was lower than that of high-copper amalgam.

• Journal of Food Hygiene and Safety
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• v.13 no.3
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• pp.305-312
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• 1998

In order to investigate the species, serobiological characteristics and antibiotic sensitivity of Pseudomonas spp, we isolated Pseudomonas spp from 57 spring waters around Seoul area for spring, summer and autumn and identified Pseudomonas spp by biochemical characteristics and serological method. And also we tested the antibiotic sensitivity test by discdiffusion method. Of 57 spring waters tested, Pseudomonas spp were isolated from 33 spring waters(57.9%). Isolation rate of Pseudomonas spp in spring season was 28.1%, summer 21.1% and autumn 28.1%. Only 1 spring water was detected Pseudomonas spp in all seasons and 9 (15.8%) were detected for 2 seasons and 13 (22.8%) were for only 1 season. Isolation rate of Pseudomonas spp at Mt. Cheonggye was 50% and followed by Mt. Bookhan 35.7%, Mt. Daemo 33.3%, Mt. Dobong 29.6%, Mt. Surak 25.9%, Mt. Woomyun 22.2% and Mt. Bulam 7.4%. Of 44 Pseudomonas spp, 22 strains (50%) were identified by Ps. putida, Ps. aeruginosa, Ps. fluorescens and Ps. mendocina were identified 6 strains (13.6%), respectively. 4 strains (9.1%) were identified by Ps. aureofaciens. Of 6 Ps. aeruginosa, serotype A was 2 strains, B, E, G, and K was 1 strain, respectively. Of 44 Pseudomonas spp, resistance rate to amoxicillin was 90.9% and followed by chloramphenicol 84.1%, tetracycline 84.1%, carbenicillin 81.8%, nalidixic acid 68.2%, neomycin 38.6%, streptomycin 31.8%, gentamicin 4.6%, kanamycin 4.6% and colistin 2.3%. Ps. aeruginosa was more sensitive to carbenicillin than other Pseudomonas spp isolated from spring waters in Seoul area but more resistant to kanamycin, and Ps. aureofaciens was no resistant to streptomycin. Among multiple drug resistance, resistance to 5 drugs was 31.8%, 4 drugs 15.9%, 7 drugs 13.6%, 1 drug and 2 drugs 4.6%, and 8 drugs 2.3%, respectively. The multiple resistance patterns detected highestly were NA-CB-C-TE-AMC (18.2%), NA-CB-N-C-TE-AMC (13.6%), CBC-TE-AMC (11.4%) and NA-CB-N-C-TE-AMC-S (9.1%).

• Microbiology and Biotechnology Letters
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• v.29 no.2
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• pp.72-77
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• 2001

Expression of f3 ~agarase Gene and Catabolite Repression in Escherichia coli by the Promoter of Alginate Lyase Gene Isolated from Marine Pseudomonas sp. Jin, Cheal~Ho, J~Hyeon Park, Jeong-Hyun Han, YoonM Hyeok Chae, Jong~Hee Lee, Jung-Kee Lee!, and In-800 Kong*. Faculty of Food Science and Biotechnology, Pukyong National UniversitYt Pusan 608-737, Korea, llnBioNet Co. 1690-3 Taejon 306-230, Korea - Promoter is a key factor for expression of the recombinant protein. There are many promoters for overexpression of protein in various organisms. The aly promoter of Pseudomonas sp. W7 isolated from marine environment was known to be a constitutive expression promoter of the alginate lyase gene, and it's promoter activity is repressed by glucose in Escherichia coli. To investigate the catabolite repression of the aly promoter ~md association between the promoter mutants, f3 agarase gene, which was also cloned from Pseudomonas sp. W7 was connected to the aly promoter with the sequence the coding 46 N-terminal amino acids ofthe alginate lyase gene. The constructed plasmid was introduced into E. coli and the agarase activity was measured. Fourty six amino acids of the alginate lyase gene was serially deleted using peR to the direction of 5' upstream region and subcloned. The agarase was overexpressed by the aly promoter and the production of agarase was repressed by the addition of glucose into culture media. Fourty six amino acids of alginate lyase did not affect the production of agarase at all. The deletion of a putative stem-loop structure in the aly promoter induced the decrease of f3 -agarase productivity.

• Archives of Pharmacal Research
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• v.25 no.5
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• pp.718-723
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• 2002

CKD-602 (7-[2-(N-isopropylamino)ethyl]-(20S)-camptothecin) is a recently-developed synthetic camptothecin analogue and currently under clinical development by Chong Kun Dang Pharm (Seoul, Korea). CKD-602 showed potent topoisomerase inhibitory activity in vitro and broad antitumor activity against various human tumor cells in vitro and in vivo in animal models. This study describes the pharmacodynamics of the immediate and delayed cytotoxicity induced by CKD-602 in a human colorectal adenocarcinoma cell line, HT-29, and its intracellular drug accumulation by HPLC. The present study was designed to address whether the higher activity of CKD-602 with prolonged exposure is due to delayed exhibition of cytotoxicity and/or an accumulation of anti proliferative effect on continuous drug exposure. The drug uptake study was performed to determine whether the delayed cytotoxicity is due to a slow drug accumulation in cells. CKD-602 produced a cytotoxicity that was exhibited immediately after treatment (immediate effect) and after treatment had been terminated (delayed effect). Both the immediate and delayed effects of CKD-602 showed a time dependent decrease in 4IC_{50}$ values. Drug uptake was biphasic and the second equilibrium level was obtained as early as at 24hr, indicating that the cumulative and delayed antitumor effects of CKD-602 were not due to slow drug uptake. On the other hand, CKD-602 treatment was sufficient to induce delayed cytotoxicity after 4hr, however, longer treatment (＞24hr) enhanced its cytotoxicity due to the intracellular accumulation of the drug, which requires 24hr to reach maximum equilibrium concentration. In addition, $C^n$$\times$T=h analysis (n=0.481) indicated that increased exposure times may contribute more to the overall antitumor activity of CKD-602 than drug concentration. Additional studies to determine the details of the intracellular uptake kinetics (e.g., concentration dependency and retention studies) are needed in order to identify the optimal treatment schedules for the successful clinical development of CKD-602.

• Pediatric Infection and Vaccine
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• v.10 no.2
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• pp.208-214
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• 2003

Purpose : We performed a retrospective study on bacterial meningitis in children, pertaining to the causative organisms, bacterial resistance to antibiotics and the effect of recent introduction of Haemophilus influenzae type b(Hib) vaccine. Methods : We analysed the forty-three cases of bacterial meningitis which had been treated at the Inha University Hospital from June 1996 to June 2003. Results : Nineteen cases(44.2%) of them were infants younger than 2 months of age, and 29 cases(67.5%) younger than 1 year of age. The common causative organisms under 2 months of age were group B streptococcus(GBS)(47.4%), E. coli(21.1%), and Klebsiella pneumoniae(21.1%). In the age group beyond 2 months of age, S. pneumoniae were seen in 50 %, H. influenzae in 16.7% and N. meningitidis in 16.7%. All of the five cases of Hib meningitis had not been vaccinated for Hib. There has been no Hib meningitis cases since 2001. Overall fatality rate was 4.5%, and complication occurred in 39%. Complications was significantly less frequent in patients resumed to be treated within 48 hours after onset compared to after 48 hours after onset. Penicillin resistance of S. pneumoniae and GBS isolated among bacterial meningitis cases was high. Conclusion : Timing of treatment after the onset of the disease appeared the most important factor for prognosis of bacterial meningitis. The cases of H. influenzae meningitis have decreased probably due to Hib vaccination.

• Journal of Korean Medical Science
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• v.33 no.47
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• pp.292.1-292.10
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• 2018

Background: We investigated the incidence of active tuberculosis among patients with inflammatory bowel disease (IBD) treated with tumor necrosis factor (TNF) inhibitors, with or without latent tuberculosis infection (LTBI). Methods: The study was performed at a Korean tertiary referral center between January 2011 and June 2017. In total, 740 patients with IBD who underwent LTBI screening tests and were followed-up for ${\geq}1$ year after TNF inhibitor treatment initiation were enrolled. LTBI was detected on the basis of tuberculin skin test results, interferon-gamma release assay results, chest X-ray findings, and previous tuberculosis treatment history. The patients were classified into LTBI (n = 84) or non-LTBI (n = 656) group. The risk of developing tuberculosis in each group was assessed on the basis of standardized incidence ratio (SIR) and 95% confidence interval (CI) for active tuberculosis. Results: Mean patient age was 33.1 years, and patients with Crohn's disease were predominant (80.7%). Within 1 year after the initiation of TNF inhibitor treatment, 1 patient in the LTBI group (1/84; 1.2%) and 7 patients in the non-LTBI group (7/656; 1.1%) developed active tuberculosis. The overall 1-year incidence of tuberculosis among the patients was significantly higher than that among the general population (SIR, 14.0; 95% CI, 7.0-28.0), and SIR was not affected by LTBI status (LTBI group: 14.5, 95% CI, 2.0-102.6; non-LTBI group: 14.0, 95% CI, 6.7-29.4). Conclusion: Patients with IBD undergoing TNF inhibitor treatment showed a higher 1-year incidence of tuberculosis than the general population irrespective of LTBI status.