• Applied Chemistry for Engineering
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• v.18 no.2
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• pp.99-110
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• 2007

Efficient and inexpensive hydrogen storage is an essential prerequisite for the utilization of hydrogen, one of the new and clean energy sources for $21^{st}$ century. In this review, several storage techniques are briefly reviewed and compared. Especially, adsorption/storage via physisorption at low temperature, by using nanoporous adsorbents, is reviewed and evaluated for further developments. The adsorption over a porous material at low temperature is currently investigated deeply to fulfill the storage target. In this review, several characteristics needed for the high hydrogen adsorption capacity are introduced. It may be summarized that following characteristics are necessary for high storage capacity over porous materials: i) high surface area and micropore volume, ii) narrow pore size, iii) strong electrostatic field, and iv) coordinatively unsaturated sites, etc. Moreover, typical results demonstrating high storage capacity over nanoporous materials are summarized. Storage capacity up to 7.5 wt% at liquid nitrogen temperature and 80 atm is reported. Competitive adsorbents that are suitable for hydrogen storage may be developed via intensive and continuous studies on design, synthesis, manufacturing and modification of nanoporous materials.

• Applied Chemistry for Engineering
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• v.26 no.6
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• pp.640-647
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• 2015

As the need for next-generation flexible electronics grows, novel materials and technologies that can replace conventional indium tin oxide (ITO) for transparent electrodes have been of great interest. Among them, a conducting polymer, especially poly(3,4-ethylenedioxythiophene) : poly(styrene sulfonate) (PEDOT : PSS) is one of the most promising candidates because it is mechanically flexible, inexpensive, and capable of being processed in solution. Currently, there are a lot of research efforts on enhancing its electrical conductivity to the level of ITO or metal electrodes through chemical and/or physical processing. In this review article, we present various additives and pre-/post-deposition processing methods for improving the electrical conductivity of PEDOT : PSS. Some of representative reports are also introduced, which demonstrated the use of conductivity-enhanced PEDOT : PSS as transparent electrodes in electronics and energy conversion.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.906-911
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• 1999

This study was to determine whether DNA 'Comet Assay' can be applied to the detection of grains irradiated with low doses of Co-60 gamma radiation. Sesame, perilla, wheat, barley and rice were exposed to different doses of 0.1, 0.3, 0.5, 0.7 and 1.0 kGy. The cells isolated from the samples were embedded in a agarose gel on a microscope slide, lysed in lysis solution, and subjected to electrophoresis. DNA and its fragments migrated in the gel produced the characteristic pattern of DNA comet, of which the tail length was measured in a microscope. All the samples irradiated at 0.3 kGy and higher were applicable to detect post-irradiation by the tail length of their comets. Irradiated samples showed comets with long tails and their tail length increased with the dose, while unirradiated samples showed no or very short tails. Especially, sesame, perilla and wheat irradiated at 0.1 kGy could be distinguished from unirradiated samples by visual inspection of the slide in a microscope. Thus, DNA 'Comet Assay' might be applied to the detection of irradiated grains as a simple, inexpensive and rapid screening test.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.17
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• pp.7351-7355
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• 2014

Background: Laryngeal carcinogenesis is a multifactorial process that has not been fully elucidated. Despite extensive research, reliable markers with diagnostic and prognostic value are still lacking. It was recently reported that an elevated preoperative neutrophil-to-lymphocyte ratio (NLR) may correlate with an increased risk of recurrence, tumor aggressiveness and poorer prognosis in various malignancies. The aim of this study was to examine whether NLR could be used as an inflammatory marker to differentiate laryngeal squamous cell carcinoma (LSCC) patients from benign laryngeal lesion (BLL) and precancerous laryngeal lesion (PLL) patients. Materials and Methods: This retrospective study was performed on 209 patients admitted to a tertiary referral center with laryngeal lesions and undergoing biopsies to establish their histopathological diagnosis. We reviewed the patient files for their clinical, histopathological and laboratory data. The patients were divided into three groups according to their histopathological findings, as BLL, PLL and LSCC groups. The patients in the PLL group were also divided into three subgroups as mild, moderate and severe dysplasia/carcinoma in situ (CIS) subgroups. The groups were compared for NLR and the other laboratory data. Results: The mean NLRs of the BLL, PLL and the LSCC groups were $2.12{\pm}0.86$, $2.32{\pm}0.68$ and $3.46{\pm}1.51$, respectively, and the difference was statistically significant (p=0.001). The mean NLRs of the patients with PLL and LSCC were significantly higher than the patients with BLL (p=0.031 and p=0.001, respectively). The mean NLRs were similar among mild dysplasia, moderate dysplasia and severe dysplasia / CIS groups (p>0.05). Conclusions: To our knowledge, this is the first study investigating NLR in BLL, PLL and LSCC. NLR is an inexpensive, reproducible and widely available blood test, and could be a useful inflammatory marker to differentiate LSCC from BLL and PLL.

• Journal of the Korean Chemical Society
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• v.45 no.4
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• pp.341-350
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• 2001

Aluminum Hydroxide was employed as a thermal retardent and flame retardent for Chloropolyethylene (CPE) rubbery materials which is the construction material of automotive oil cooler hose. and then cure characteristics, physical properties, thermal resistance and flame retardation of compounded rubber were investigated, and optimum mixing conditions of rubber and flame retarding agent were deduced from the experimental results. CPE rubber material which has excellent properties of chemical corrosion resistance and cold resistance and inexpensive in price was used to prepare rubber specimen. The by-product of ething, produced from the process of surface treatment of aluminum was processed to aluminum hydroxide via crushing and purification, which is characterized by XRD, PSA, SEM and ICP-AES techniques in terms of phase, size, distribution, morphology and components of particles and then mixed to CPE rubber materials in the range of 0~80 phr. Hardness, tensile strength, elongation and thermal properties of compounded rubber specimens were tested. The optimum mixing ratio of rubber to additives to give maximum effect on thermal resistance and flame retardation, within the range of tolerable specification for rubber materials, was determined to be 40 phr. The flame retardation of CPE rubber materials was found to be increased by 5 times at this mixing ratio.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.46 no.4
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• pp.28-38
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• 2009

In this study, a remote air quality monitoring system for underground spaces was developed by using NDIR-based CO$_2$ sensor. And the remote monitoring system based on wireless sensor networks was installed practically on the subway station platform. More than 6.5 million citizens commutate everyday by the Seoul subway transportation that is the most typical public transportation. They concern about air quality with increasing interest on public health or many workers in subway stations or underground shopping centers. Recently, the Korean Ministry of Environment has operated the air quality monitoring system in some subway stations for testing phase. However, it showed many defects which are large-scale, high-cost and maintenance of precision sensors imported from abroad. Therefore this research includes the reliability test and a theoretical study about the inexpensive commercialized CO$_2$ sensor for reliable measurement of air quality which changes rapidly by the surrounding environments. And then we develop the wireless sensor nodes and the gateway applied for remote air quality monitoring. In addition, web server program was realized to manage air quality in the subway platform. This result will be valuable for a basic research for air quality management in underground spaces for future study.

• Korean Journal of Clinical Pharmacy
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• v.15 no.2
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• pp.75-81
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• 2005

Community acquired pneumonia (CAP) remains a prevalent and potentially life threatening illness. American Thoracic Society and Infectious Disease Society America recommend combination therapies with ${\beta}-lactam$ plus a macrolide or a fluoroquinolone monotherapy for the empirical treatment of CAP. The aim of this study was to compare moxifloxacin monotherapy with cephalosporin plus azithromycin combination therapies. From January 2004 to March 2005, 18 patients in the moxifloxacin group(MG) and 21 patients in the cefuroxime or ceftriaxone plus azithromycin group(CAG) with CAP were retrospectively reviewed with regard to clinical, laboratory and microbiological data. Each patient was stratified into mild (risk class I-II), moderate (risk class III) and severe (risk class VI, V) group according to and PSI (Pneumonia Severity Index) score. Each group was compared for microbiological eradication, clinical assessment, the length of hospital stay. As results, Total 39 patients with CAP were reviewed. The appropriateness of admission was 83.3% in MC vs. 76.2% in CAC. The mean length of the hospital day was for 8.31 days vs. 7.39 days, days switching parenteral to oral antibiotics in 5.19 days vs. 5.28 days, clinical improvement in 2.43 days vs. 2.61 days in MG vs. CAC. Radiological improvement required 3.75 days vs 3.63 days in MG vs. CAG and bacteriological eradication rate at discharge was the same in the both groups. Mortality rate was 11.1% (2 of 18) vs 14.3% (3 of 21) in MG vs. CAG (p=0.77). Drug cost of the mean 5 hospital days requiring parenteral antibiotics was the most inexpensive in moxifloxacin group for the 147,045 won, and ceftriaxone 1g-azithromycin group for the 170,285 won, cefuroxime bid-azithromycin group for the 207,800 won, ceftriaxone 2g-azithromycin group far the 220,570 won, cefuroxime tid-azithromycin group for the 251,700 won. There was no significant statistical difference in clinical, bacterial, radiological cure and hospital days, and switch to oral days. In conclusion, that i.v. moxifloxacin monotherapy was as effective as azithromycin plus cefuroxime or ceftriaxone combination therapies fur the treatment of CAP. In drug cost analysis, moxifloxacin is less expensive than CAG.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.3
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• pp.213-220
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• 2015

Wireless sensor network(WSN) is made up of a lot of battery operated inexpensive sensors that, once deployed, can not be replaced. Therefore, energy efficiency of WSN is essential. Among the methods for energy efficiency of the network, clustering algorithms, which divide a WSN into multiple smaller clusters and separate all sensors into cluster heads and their associated member nodes, are very energy efficient routing technique. The first cluster-based routing protocol, LEACH, randomly elects the cluster heads in accordance with the probability. However, if the distribution of selected cluster heads is not good, uniform energy consumption of cluster heads is not guaranteed and it is possible to decrease the number of active nodes. Here we propose a new routing scheme that, by comparing the remaining energy of all nodes in a cluster, selects the maximum remaining energy node as a cluster head. Because of decrease in energy gap of nodes, the node that was a cluster head operates as a member node much over. As a result, the network lifespan is increased and more data arrives at base station.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.984-991
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• 2006

Effects of spent composts of selenium-enriched mushroom (Se-SMC) on plasma glutathione peroxidase (GSH-Px) activity and selenium (Se) deposition in finishing Hanwoo (Bos taurus coreanae) steers were investigated. Twenty-five Hanwoo steers (average body weight = 613 kg, average age = 22 months) were allotted to treatments in five groups of five steers per pen for 12 weeks preceding slaughter. Treatments were SMC alone (CON; 0.1 ppm Se), 0.3 ppm (0.3 Se-SMC), 0.6 ppm (0.6 Se-SMC), 0.9 ppm (0.9 Se-SMC), and 0.9 ppm (sodium selenite; SENI) Se. During the experimental period, blood samples were taken to analyze Se concentrations and GSH-Px activities. Muscle and liver samples were collected for analyses of Se contents after slaughter. Dry matter intake and body weight gain were not affected by Se-SMC or sodium selenite supplementation. Selenium concentration in the whole blood and GSH-Px activity in plasma were linearly increased (p<0.01) with increasing levels of Se-SMC. The whole blood Se concentration of SENI treatment was significantly higher (p<0.05) than that of CON treatment from 4 weeks, whereas there was no significant difference in GSH-Px activities between both treatments at 8 and 12 weeks. Selenium content in the hind leg and liver increased linearly (p<0.05) with increasing levels of Se-SMC, but those of SENI treatments were not significantly different from CON treatments. These results suggested that Se in the Se-SMC was highly bioavailable to blood and tissues of ruminants, especially compared with Se in the sodium selenite. Therefore, Se-SMC might be used not only as an inexpensive way of providing Se for ruminants but also as another way of producing Se-fortified beef.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.6041-6048
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• 2013

Background: Japanese women in their 40s or older have been encouraged to attend breast cancer screening. However, the breast cancer screening rate in Japan is not as high as in Europe and the United States. The aim of this study was to identify psychological and personal characteristics of women concerning their participation in breast cancer screening using the Health Belief Model (HBM). In addition, the attributes of screening more easily accepted by participants were analyzed by conjoint analysis. Materials and Methods: In this cross sectional study of 3,200 age 20-69 women, data were collected by an anonymous questionnaire. Questions were based on HBM and personal characteristics, and included attitudes on hypothetical screening attributes. Data of women aged 40-69 were analyzed by logistic regression and conjoint analysis to clarify the factors affecting their participation in breast cancer screening. Results: Among responses collected from 1,280 women of age 20-69, the replies of 993 women of age 40-69 were used in the analysis. Regarding the psychological characteristics based on HBM, the odds ratios were significantly higher in "importance of cancer screening" (95%CI: 1.21-2.47) and "benefits of cancer screening" (95%CI: 1.09-2.49), whereas the odds ratio was significantly lower in "barriers to participation before cancer screening" (95%CI: 0.27-0.51). Conjoint analysis revealed that the respondents, overall, preferred screening to be low cost and by female staff members. Furthermore, it was also clarified that attributes of screening dominant in decision-making were influenced by the employment status and the type of medical insurance of the women. Conclusions: In order to increase participation in breast cancer screening, it is necessary to disseminate accurate knowledge on cancer screening and to reduce barriers to participation. In addition, the attributes of screening more easily accepted were inexpensive, provided by female staff, executed in a hospital and finished in a short time.