• Progress in Medical Physics
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• v.27 no.3
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• pp.156-161
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• 2016

When air discharged from a radioisotope production facility is contaminated with radiation, the public may be exposed to radiation. The objective of this study is to manage such radiation exposure. We measured the airborne radioactivity concentration at a 30 MeV cyclotron radioisotope production facility to assess whether the exhaust gas was contaminated. Additionally, we investigted the radioactive contamination of the air filter for efficient air purification and radiation safety control. To measure the airborne radiation concentration, specimens were collected weekly for 4 h after the beginning of the radioisotope production. Regarding the air purifier, five specimens were collected at different positions of each filter-pre-filter, high-efficiency particulate air filter, and charcoal filter-installed in the cyclotron production room. The concentrations of F-18, I-123, I-131, and Tl-201 generated in the radioiodine production room were $13.5Bq/m^3$, $27.0Bq/m^3$, $0.10Bq/m^3$, and $11.5Bq/m^3$, respectively; the concentrations of F-18, I-123, and I-131 produced in the radioisotope production room were $0.05Bq/m^3$, $16.1Bq/m^3$, and $0.45Bq/m^3$, correspondingly; and those of F-18, I-123, I-131, and Tl-201 generated in the accelerator room were $2.07Bq/m^3$, $53.0Bq/m^3$, $0.37Bq/m^3$, and $0.15Bq/m^3$, respectively. The maximum radiation concentration of I-123 generated in the radioiodine production room was 1,820 Bq/g, which can be disposed after 2 days. The maximum radiation concentration of Tl-202 generated in the radioisotope production room was 205 Bq/g, and this isotope must be stored for 53 days. The I-123 generated in the radioiodine production room had a maximum concentration of 1,530 Bq/g and must be stored for 2 days. The maximum radiation concentration of Na-22 generated in the radioisotope production room was 0.18 Bq/g and this isotope must be disposed after 827 days. To manage the exhaust, the efficiency of air purification must be enhanced by selecting an air purifier with a long life and determining the appropriate replacement time by examining the differential pressure through systematic measurements of the airborne radiation contamination level.

• Korean Journal of Medicinal Crop Science
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• v.7 no.1
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• pp.31-36
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• 1999

This study was carried out to investigate the effect of sulfuric fertilizers on allylisothiocyanate(allylNCS) content of upland Wasabia japonica Matsum cultivated in heating condition in the winter season. The rhizome's growth characters following soil application of sulfur dust were not significantly different compared to control, though its soil acidity and available sulfur content was higher than other treatments. Total sulfur content of plant was increased by soil application as compared to foliar application and allylNCS content of rhizome increased up to 22.8% in the sulfur dust treatment. The result showed that soil application was effective for supplying $SO_4^{-2}$ in upland Wasabia japonica Matsum when cultivated in heating condition. In the analysis of correlation coefficients between growth and quality characteristics, allylNCS content of rhizome showed the significantly positive correlation with total sulfur content of shoot, rhizome and allylNCS content of shoot.

• Journal of Digital Convergence
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• v.13 no.1
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• pp.297-304
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• 2015

Recently, the demand for a PRT(Personal Rapid Transit) system based on autonomous navigation is increasing. Accordingly, the applicability investigations of the PRT system on rail tracks or roadways have been widely studied. In the case of unmanned vehicle operations without physical guideways on roadways, to monitor the position of the vehicle in real time is very important for stable, robust and reliable guidance of an autonomous vehicle. The Global Positioning System (GPS) has been commercially used for vehicle positioning. However, it cannot be applied in environments as tunnels or interiors of buildings. The PRT navigation system based on magnetic markers reference sensing that can overcome these environmental restrictions and the vehicle dynamics model for its H/W configuration are presented in this study. In addition, the design of a control S/W dedicated for unmanned operation of a PRT vehicle and its prototype implementation for experimental validation on a pilot network were successfully achieved.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.229-229
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• 2010

With the scaling down of ultra large integrated circuits (ULSI) to the sub-50 nm technology node, the need for an ultra-thin, continuous and conformal diffusion barrier and Cu seed layer is increasing. However, diffusion barrier and Cu seed layer formation with a physical vapor deposition (PVD) method has become difficult as the technology node is reduced to 30 nm and beyond. Recent work on self-forming barrier processes using PVD Cu alloys have attracted great attention due to the capability of conformal ultra-thin barrier formation using a simple technique. However, as in the case of the conventional barrier and Cu seed layer, PVD of the Cu alloy seed layer will eventually encounter the difficulty in conformal deposition in narrow line trenches and via holes. Atomic layer deposition (ALD) has been known for its good step coverage and precise thickness control, and is a candidate technique for the formation of a thin conformal barrier layer and Cu seed layer. Conformal Cu-Mn seed layers were deposited by plasma enhanced atomic layer deposition (PEALD) at low temperature ($120^{\circ}C$), and the Mn content in the Cu-Mn alloys were controlled form 0 to approximately 10 atomic percent with various Mn precursor feeding times. Resistivity of the Cu-Mn alloy films decreased by annealing due to out-diffusion of Mn atoms. Out-diffused Mn atoms were segregated to the surface of the film and interface between a Cu-Mn alloy and $SiO_2$, resulting in self-formed $MnO_x$ and $MnSi_xO_y$, respectively. No inter-diffusion was observed between Cu and $SiO_2$ after annealing at $500^{\circ}C$ for 12 h, indicating an excellent diffusion barrier property of the $MnSi_xO_y$. The adhesion between Cu and $SiO_2$ was enhanced by the formation of $MnSi_xO_y$. Continuous and conductive Cu-Mn seed layers were deposited with PEALD into 32 nm $SiO_2$ trench, enabling a low temperature process, and the trench was perfectly filled using electrochemical plating (ECD) under conventional conditions. Thus, it is the resultant self-forming barrier process with PEALD Cu-Mn alloy film as a seed layer for plating Cu that has further potential to meet the requirement of the smaller than 30 nm node.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.2
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• pp.63-70
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• 2006

Natural product compounds are the source of numerous therapeutic agents. The marine environment produces natural products from a variety of structural classes exhibiting activity against numerous disease targets including anticancer agents. Among these, pectenotoxin-2 (PTX-2), which was first identified as a cytotoxic entity in marine sponges, which depolymerizes actin filaments, was found to be highly effective and more potent to activate an intrinsic pathway of apoptosis in p53-deficient tumor cells compared to those with functional p53 both in vitro and in vivo. However, the anti-proliferative mechanism of the compound at non-cytotoxic concentrations has not yet been explored. In the current study, we sought to investigate anti-proliferation and apoptosis of PTX-2 against U937 human leukemic cells and its underlying molecular mechanism. Exposure of U937 cells to PTX-2 resulted in growth inhibition and induction of apoptosis in dose- and time-dependent manner as measured by MTT assay, fluorescent microscopy and flow cytometric analysis. The anti-proliferative effect of PTX-2 was associated with a marked increase in the expression of cyclin-dependent kinase p21 (WAF1/CIP1) mRNA which was tumor suppressor p53-independent. The increase in apoptosis was connected with a time-dependent down-regulation of anti-apoptotic Bcl-XL and inhibitor of apoptosis proteins (IAPs) family such as XIAP and cIAP-2. Though additional studies are needed, these findings suggested that PTX-2-induced inhibition of U937 cells was associated with the induction of apoptotic cell death and the results provided important new insights into the possible molecular mechanisms of the anti-cancer activity of PTX-2.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.138-143
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• 2003

Total methanolic extract of Chrysanthemum coronarium L. var. spatiosum (Compositae) was revealed to have anti-hepatotoxic activity against galactosamine-induced toxicity on primary cultured rat hepatocytes. After successive partitioning with chloroform, n-butanol, and water, the chloroform fraction showed a significant inhibition activity of 51% at 50 ppm, compared with that of silybin, 45.9% at $100\;{\mu}M$. The chloroform fraction was subjected to silica gel column chromatography and yielded active CH-II, CH-V and CH-VI subfractions, and the anti-hepatotoxic activity of these subfractions were 47.6, 56.3, and 23.2%, respectively, at 50 ppm. Total glutathione contents of CH-II, CH-V, and CH-VI increased by 49.8, 43.9, and 47.5% of the control, respectively at 50 ppm, whereas that of silymarin was, 59.7% at $100\;{\mu}M$ after challenged with galactosamine. The ratio of (reduced glutathione) / (total glutathione) in CH-II, CH-V and CH-VI subfraction showed similar values of $0.86{\sim}0.87$ at 50 ppm, whereas that of silymarin was, 0.85 at $100\;{\mu}M$. The incorporation of $[^3H]-uridine$ uptake into RNA was not affected by these active subfractions.

• Journal of the Korean Society for Marine Environment & Energy
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• v.16 no.1
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• pp.9-16
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• 2013

An experiment was conducted to evaluate the biochemical adverse effect of increased carbon dioxide in seawater on marine polychaete, Perinereis aibuhitensis. We measured the available energy reserves, Ea (total carbohydrate, protein, and lipid content) and the energy consumption, Ec (electron transport activity) of Perinereis aibuhitensis exposed for 7-d to a range of $CO_2$ concentration such as 0.39 (control =390 ppmv), 3.03 (=3,030 ppmv), 10.3 (=10,300 ppmv), and 30.1 (=30,100 ppmv) $CO_2$ mM, respectively. The cellular energy allocation (CEA) methodology was used to assess the adverse effects of toxic stress on the energy budget of the test organisms. The results of a decrease in CEA effect of increased carbon dioxide in seawater from all individual in Ea and Ec. Increase of carbon dioxide reduced pH in seawater, significantly. The chemical changes in sea- water caused by increasing $pCO_2$ might cause stresses to test organisms and changes in the cellular energy allocations. Results of this study can be used to understand the possible influence of $CO_2$ concentration increased by the leakage from sub-sea bed storage sites as well as fossil fuel combustion on marine organisms.

• Korean Journal of Food Science and Technology
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• v.49 no.6
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• pp.676-684
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• 2017

The present study aimed to examine the hepatoprotective effects of ethanol extracts from steam-dried ginseng berry (SGBE) in both $\text\tiny{D}$-Galactosamine/Lipopolysaccharide ($\text\tiny{D}$-GalN/LPS)-sensitized mice and in vitro models. Our results clearly demonstrated that SGBE significantly reduced the level of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase in blood, and $TNF{\alpha}$ was normalized in 8 h after the treatment with $\text\tiny{D}$-GalN/LPS. Coincidently, major organs remained unimpaired when compared to $\text\tiny{D}$-GalN/LPS control group. Moreover, p38, which stimulates expression of NAFLD-associated cytokines, was markedly inhibited when treated with SGBE. In vitro analysis revealed that the main components of SGBE, linoleic acid and ginsenoside Re/Rd, may play a role in protecting liver from $\text\tiny{D}$-GalN/LPS-induced toxicity. Finally, we concluded that SGBE may be a promising therapeutic agent for preventing damage to the liver.

• Journal of Bio-Environment Control
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• v.25 no.2
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• pp.106-110
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• 2016

In this study, a planting density-growth-harvest (PGH) chart was developed to easily read the growth and harvest factors such as crop growth rate, relative growth rate, shoot fresh weight, shoot dry weight, harvesting time, marketable rate, and marketable yield of common ice plant (Mesembryanthemum crystallinum L.). The plants were grown in a nutrient film technique (NFT) system in a closed-type plant factory using fluorescent lamps with three-band radiation under a light intensity of $140{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and a photoperiod of 12 h. Growth and yield were analyzed under four planting densities ($15{\times}10cm$, $15{\times}15cm$, $15{\times}20cm$, and $15{\times}25cm$). Shoot fresh and dry weights per plant increased at a higher planting density until reached an upper limit and yield per area was also same tendency. Crop growth rate, relative growth rate and lost time were described using quadratic equation. A linear relationship between shoot dry weight and fresh weights was observed. PGH chart was constructed based on the growth data and making equations. For instance, with within row spacing (= 20 cm) and fresh weight per plant at harvest (= 100 g), we can estimate all the growth and harvest factors of common ice plant. The planting density, crop growth rate, relative growth rate, lost time, shoot dry weight per plant, harvesting time, and yield were $33plants/m^2$, $20g{\cdot}m^{-2}{\cdot}d^{-1}$, $0.27g{\cdot}g^{-1}{\cdot}d^{-1}$, 22 days, 2.5 g/plant, 26 days after transplanting, and $3.2kg{\cdot}m^{-2}$, respectively. With this chart, we could easily obtain the growth factors such as planting density, crop growth rate, relative growth rate, lost time and the harvest factors such as shoot fresh and dry weights, harvesting time, marketable rate, and marketable yield with at least two parameters, for instance, planting distance and one of harvest factors of plant. PGH charts will be useful tools to estimate the growth and yield of crops and to practical design of a closed-type plant production system.

• Journal of Korean Society of Forest Science
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• v.100 no.1
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• pp.112-117
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• 2011

This study was conducted for searching the functional feeding groups, and community stability of the macroinvertebrate on forest fire area of Uljin-gun. The samples were collected from 2 sites of control area and 2 sites of experimental area during 2007 to 2009. The identified species were 89 belonged to 47 families, 16 order, 6 class, and 4 phylum in control area. And 84 belonged to 43 families, 16 order, 6 class, and 4 phylum were identified in experimental area. As a result of changes in species and individuals of E.P.T. taxa investigated in experimental area by year, Ephemeroptera was 21 species, $2,434.6inds./m^2$, Plecoptera was 3 species, $199.8inds./m^2$, and Trichoptera 14 species, $540.2inds./m^2$ in 2007. And in 2009, Ephemeroptera was 9 species, $296inds./m^2$, Trichoptera was 4 species, $44.4inds./m^2$, and Plecoptera was none, showing that species and individuals belonging to E.P.T. taxa decrease rapidly every year. Community analysis by year, in 2008 when the water system started to be influenced by the fire directly, it showed a trend that H' and RI decreased in the experimental area. Functional feeding group by year, it showed a trend that species and individuals of GC type which is a functional group picking up and eating FPOM (fine particulate organic matter) from deposits in the bottom of water or benthic areas and performs an important function of material circulation in ecosystem decrease every year. Community stability by year, an environment of water system in forest fire area started to be somewhat destroyed, from 2008, it is shown that both species in I area which have great ability of resistance and recovery and species in III area which live in relatively stable water system decreased a little.