• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.2
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• pp.267-272
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• 2004

This case report describes an uncommon treatment method for crown-root fractured incisor with immature root. A 7-year-old girl was referred for treatment of crown-root fractured maxillary central incisor. The fracture line extended to 1/2 of the total tooth length with incomplete root formation. The prognosis of crown-root fracture is usually poor and extraction is usually undertaken. But, in the mixed dentition, extraction of maxillary permanent incisor results in many complications, such as resorption of alveolar bone, poor esthetics, pronunciation and mastication. Conservative therapy in the permanent dentition comprises of few treatment modalities; supragingival restoration, gingivectomy, orthodontic extraction of apical fragment, surgical extrusion of apical fragment with or without rotational replantation. However, in this case, these indications are not applicable, so intentional replantation with adhesive resin system is the treatment of choice. The tooth was followed-up for 12 months. Currently, there are no symptoms. Since this modality adopts the respective advantages of both intentional replantation and adhesive treatment, it might be the treatment of choice in cases of vertical crown-root fracture.

• Tuberculosis and Respiratory Diseases
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• v.48 no.4
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• pp.464-470
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• 2000

Background : The recognition of bronchial asthma as an inflammatory disease led to the search for soluble markers that would be useful in assessing airway inflammation. Interleukin-6 (IL-6) is a representative proinflammatory cytokine that has been shown to be connected with various inflammatory diseases. IL-6 acts via specific receptors that consist of the IL-6 binding glycoprotein gp80 and the signal transducer gp130. In the search for markers of airway inflammation, delete the role of soluble interleukin-6 receptor (sIL-6R) and IL-6 in acute asthma were investigated. Methods : Serum levels of sIL-6R and IL-6 were measured in 78 acute asthmatics, in 15 patients with asymptomatic asthma and in 10 healthy control subjects by a specific ELISA using a murine antihuman IL-6R, IL-6 mAb ($Quantikine^{(R)}sIL$-6R, IL-6). Results : Serum levels of IL-6 in acute asthmatics significantly exceeded those of control subjects. The levels of sIL-6R in acute asthmatics were also significantly increased compared to those of control subjects. The serum concentrations of IL-6 obtained in acute asthmatics were elevated compared with those in asymptomatic asthmatics. However, association between eosinophilic count/IgE and IL-6/sIL-6R in acute asthma could not be found. Conclusion : Our results suggest that IL-6 may be involved in the pathogenesis of acute asthma, and serum levels of IL-6 and sIL-6R may reflect the severity of airway inflammation.

• Tuberculosis and Respiratory Diseases
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• v.58 no.1
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• pp.25-30
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• 2005

Background : An insertion-deletion polymorphism of angiotensin converting enzyme (ACE) gene has been shown to be associated with enzyme activity levels of ACE. Reported results that have been mutually contradictory about asthmatic hypersensitiveness and occurrence according to ACE gene insertion (I)/deletion (D) polymorphism. Also, the involvement of the ACE genes as the genetic basis of bronchial asthma is currently controversy. We investigated whether there was any association between polymorphisms of the ACE genes and airway hyper-responsiveness in chronic obstructive pulmonary disease (COPD). Methods : A total of 100 patients with COPD were enrolled in this study. The ACE genotypes were determined in all subjects by polymerase chain reaction. Pulmonary function test including bronchodilator response (BDR), methacholine bronchial provocation test (MBPT) were done in those patients. Airway hyper-responsiveness include any findings of positive BDR or MBPT. Results : In COPD patients, the ACE genotype distribution did not differ significantly among groups of patients with severities of COPD, and with or without airway hyper-responsiveness. Conclusions : These results suggest that polymorphisms of the ACE gene may not be associated with airway hyper-responsiveness, development and severity of COPD.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.4
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• pp.491-498
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• 2012

Recently, many papers have been proposed in order to improve the OFDM system performance in T-DMB DOCR (Digital On Channel Repeater), by using removing the feedback signal so that the transmitter power can be increased or by using the equalizer to remove ICI. Despite these efforts, however, signal quality at the receiving terminal has not been improved because of constellation smearing in T-DMB DOCR. In this paper, in order to suppress constellation smearing, we propose an effective equalizer algorithm that can improve system performance. We perform adaptive channel estimation and non-coherent decision directed noise cancellation method that can estimate the channel subsequently during data symbols period in the frequency domain. So we can obtain better quality of the signal at the receiving terminal. In order to secure QoS(Quality of Service) required in T-DMB handsets, we evaluate SNR and BER in T-DMB DOCR(Digital On Channel Repeater) and verified by simulation. In this simulation results, this system is satisfied the performance of BER=$10^{-5}$ at less than SNR=14 dB at the receiver after compensation of phase noise -18 dBc.

• Journal of Environmental Policy
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• v.5 no.3
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• pp.25-56
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• 2006

We reviewed and compared nationwide surveys conducted in advanced countries (i.e., Japan, Germany, USA, and UK) with those in Korea, including the third Nationwide Survey of Natural Environments, which began in 2006 and will proceed until 2010. Based on this comparative analysis, we suggest alternatives to the nationwide survey of natural environments that are suited to Korea. Given the focus on species abundances and distributions in previous nationwide surveys in Korea, surveys of habitats, ecosystems, and ecoregions are required to more effectively protect biological resources in Korea. Furthermore, their spatial distributions should be mapped using periodical satellite images and aerial photographs. In particular, satellite images can be used to survey species, habitats, and ecosystems. Natural resources monitoring and management specialists are needed to collect various data and improve survey results. The participation of community volunteers is also important to develop an awareness in local residents of natural environment conservation. Independent survey institute (i.e., a 'National Ecosystem Institute') should be established to develop a database and survey scheme for species, habitats, and ecosystems throughout Korea. Moreover, the survey institute could develop natural environmental policy through the data analysis to meet the objectives of the Convention on Biological Diversity. The establishment of a survey institute will allow the completion of a natural environment survey that considers various factors, including physical habitat conditions. This will allow us to detect subtle changes in species abundance and spatial distributions and provide accurate and timely information on natural environments.

• Animal cells and systems
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• v.16 no.1
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• pp.11-19
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• 2012

A major concern regarding the collection and storage of biodiversity information is the inefficiency of conventional taxonomic approaches in dealing with a large number of species. This inefficiency has increased the demand for automated, rapid, and reliable molecular identification systems and large-scale biological databases. DNA-based taxonomic approaches are now arguably a necessity in biodiversity studies. In particular, DNA barcoding using short DNA sequences provides an effective molecular tool for species identification. We constructed a large-scale database system that holds a collection of 5531 barcode sequences from 2429 Korean species. The Korea Barcode of Life database (KBOL, http://koreabarcode.org) is a web-based database system that is used for compiling a high volume of DNA barcode data and identifying unknown biological specimens. With the KBOL system, users can not only link DNA barcodes and biological information but can also undertake conservation activities, including environmental management, monitoring, and detecting significant organisms.

• Polymer(Korea)
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• v.30 no.2
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• pp.140-145
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• 2006

The mort commonly available substrate material is glass in the display fibrication process. However, glass is not desirable due to its heaviness and fragility. Recently, plastics such polysulfone (PSF), polyethesulfone (PES), polycarbonate (PC), polyethylene terephthalate (PET) and cyclic olefin polymers (COP) have been investigated to replace glass as a substrate material for display fibrication. Plastic substrates are advantageous in that they are lightweight, huh impart resistance, flexibility, and ability for roll to roll manufacturing process. But many plastics have poor chemical resistance in organic solvent. The chemica resistance is also lequired because they are exposed to solvents for various chemical treatments din the manufacturing process. So, we have an interest in the chemical modification of PSF to improve chemical resistance. We introduced crosslinkable imide moieties using chloromethylation method for the modification of PSF which could be overcome above shortcomings for display substrate based on plastic film. We prepared the cross-linked polysulfone films which were represented chemical resistance in HeOH, THF, DMSO and NMP. The thermal properties were measured by TGA, DSC and TMA. As the results, we have confirmed to enhance of the thermal property. They had low coefficient of thermal expansion (CTE) which decreased to 15% and had increased $T_g\;from\;180^{\circ}C\;to\;252^{\circ}C$. Cross-linked polysulfone films with imide side-chain had good optical properties and chemical resistance so that they could be used as flexible display substrate.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.3 s.52
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• pp.219-236
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• 2005

Glycolic acid, an alpha-hydroxy acid derived from fruit and milk sugars, has been commonly used as a cosmetic ingredient since it was known to have photo-protective, anti-inflammatory effects, and anti-oxidant effect in UV-irradiated skin. However, little has been know about the functional role of glycolic acid on UV-induced skin cell proliferation. It was previously found that glycolic acid inhibited UV-induced skin tumor development in hairless mouse. As a possible mechanism of glycolic acid on the UV-induced skin tumor development, the ability of glycolic acid to inhibit the UVB-induced cell growth and possible mechanisms were investigated. Glycolic acid treatment attenuated the UV-induced cell proliferation and apoptotic cell death in the skin. In vitro study, glycolic acid inhibited the UVB-induced cell growth and apoptotic death through inhibiting caspase-3 activity. These results suggest that glycolic acid may exert the Inhibitory effect on the UVB-induced skin tumor development by regulating cell growth and apoptotic cell death.

• Clean Technology
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• v.17 no.4
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• pp.346-352
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• 2011

The adsorption characteristics of propineb pesticide onto activated carbon has been investigated for the adsorption in aqueous solution with respect to initial concentration, contact time and temperature in batch experiment. The Langmuir and Freundlich adsorption models were applied to described the equilibrium isotherms and isotherm constants were also determined. The Freundlich model agrees with experimental data well. slope of isotherm line indicate that activated carbon could be employed as effective treatment for removal of propineb. The pseudo first order, pseudo second order kinetic models were use to describe the kinetic data and rate constants were evaluated. The adsorption process followed a pseudo second order model, and the adsorption rate constant($k_2$) decreased with increasing initial concentration of propineb. The activation energy, change of free energy, enthalpy, and entropy were also calculated to predict the nature adsorption. The estimated values for change of free energy were -7.28, -8.27 and -11.66 kJ/mol over activated carbon at 298, 308 and 318 K, respectively. The results indicated toward a spontaneous process. The positive value for change of enthalpy, 54.46 kJ/mol, found that the adsorption of propineb on activated carbon is an endothermic process.

• Journal of the Korean Chemical Society
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• v.38 no.9
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• pp.667-675
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• 1994

The precipitate flotation using $La(OH)_3$ as a coprecipitant was studied for the simultaneous determination of trace three elements in a sea water. Several experimental conditions such as pH, coprecipitant and surfactant were investigated with an artificial sea water. To remove the influence of Cr(VI) the Cr(VI) was reduced to Cr(III) using $NaBH_4$ prior to the flotation. Trace amounts of Cu(II), Co(II) and total Cr in 1.0 l sea water was coprecipitated together with the precipitation of $La(OH)_3$ in the solution of pH 9.8 adjusted with 3.OM NaOH solution. The precipitate was floated by using a mixed surfactant (1 to 8 of each 0.5% ethanolic sodium oleate and sodium dodecylsulfate solution) by bubbling a nitrogen gas. The floats was separated and filtrated from the mother liquor by suction. The precipitate was dissolved in 7.0 M $HNO_3$ solution and then marked to 25.0 ml with a deionized water. These elements were determined by graphite fumace atomic absorption spectrophotometry. This method was applied to determine the elements in the sea water of the Eastern and Western coasts. And the recoveries were over 90.0% in the samples into which given amounts of the analyte elements were spiked.