• Journal of Chest Surgery
• /
• v.42 no.2
• /
• pp.157-164
• /
• 2009

Background: Various studies and experimental trials have been done to develop bioprosthetic devices to treat complex congenital heart disease due to the limited usage of homograft tissue. The purpose of the present study was to evaluate the effect of diamine bridges with using L-lysine, as compared with using ethanol. Material and Method: Porcine pericardium was fixed at 0.625% GA (commercial fixation). An interim step of ethanol (80%; 1 day at room temperature) or L-lysine (0.1 M; 2 days at $37^{\circ}C$) was followed by completion of the GA fixation (2 days at $4^{\circ}C$ and 7 days at room temperature). The tensile strength and thickness of the porcine percardium were measured, respectively. The treated pericardiums were implanted subcutaneously into three-week old Long-Evans rats for 8 weeks. The calcium content of the implants was assessed by atomic absorption spectroscopy and the histology. Result: Ethanol pretreatment ($13.6{\pm}10.0ug/mg$, p=0.008), L-lysine pretreatment ($15.3{\pm}1.0 ug/mg$, p=0.002), and both treatment ($16.1{\pm}11.1ug/mg$, p=0.012) significantly inhibited calcification, as compared with the controls $(51.2{\pm}8.5ug/mg)$. L-lysine pretreatment ($0.18{\pm}0.02mm,\;1.20{\pm}0.30kg$ f/5 mm) significantly increased the thickness and tensile strength, as compared with ethanol pretreatment ($0.13{\pm}0.03mm,\;0.85{\pm}0.36$ 1.0 kg f/5 mm) (p<0.01, p=0.035). Conclusion: The diamine bridges using L-lysine seemed to decrease the calcification of porcine pericardium fixed with glutaraldehyde, and this was comparable with Ethanol. Additionally, it seemed to enhance the thickness and tensile strength.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.11 no.3
• /
• pp.150-159
• /
• 2008

The marine litter generated as by-products of human activities and economic development enters to the sea through rivers or stream Indirectly, and through sea-based activities directly. It is commonly comprised of materials that degrade very slowly, such as various plastic products, polystyrene, glass, rubber, metal, wood, derelict fishing nets, wire, rope and so on. Such litter is found in the water column and on the seafloor as well as coastal areas In the Northwest Pacific region. It causes injury or death of human and other living organisms and also accident or damage of the vessel. It is not only a problem of country but also regional and/or global problem because it is transported by currents and winds from one country to another. In this regard, Northwest Pacific Action Plan (NOWPAP) Marine Litter Activity (MALITA) project had been carried out during 2006-2007 biennium and NOWPAP Regional Action Plan on Marine Litter (RAP MALI) has been also continuously implemented in the 2008-2009 biennium as next phase step of MALITA. MERRAC, one of four Regional Activity Centres (RACs) of NOWPAP, has developed monitoring guidelines, sectoral guidelines, and brochures related to sea-based marine litter and port reception facilities and services through MALITA project. Based upon these output, MERRAC will continuously implement relevant activities of RAP MALI in order to help to establish and improve a regional mechanism to deal with the sea-based marine litter problem. This paper aims to introduce MERRAC activities under MALITA and RAP MALI, and to suggest several recommendations to reduce marine litter in the NOWPAP region.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.33 no.1
• /
• pp.21-30
• /
• 2015

Bulguksa Temple, a typical temple of Silla was lost during Japanese Invasion of Korea and there are records of reconstructing in its record, Bulguksa Sajeok. There is no record after that. And reconstructing was stopped due to lack of money and repair works were conducted for two times in Japanese colonial era. First repair work was from 1989 to 1919 and second repair work was conducted from 1922 to 1925. After Liberation, Bulguksa Temple Restoration Committee was established in 1969 and the construction has started since 1970 after excavation investigation to complete in 1973. The shape of south arcade without walls in the main temple of Bulguksa was found in a blue print of Bulguksa in Japanese colonial era in National Archives of Korea now and a picture of Bulguksa in 1902 taken by Sekino Tadashi. It verified the correlation between Gupumyeonji which was discovered in restoration work in 1970s and a legend of Muyoungtap. And a stair from the hall of Paradise to the main temple was introduced as a stair including Pure Land Buddhism doctrine in many literature materials, but a blue print of Bulguksa in Japanese colonial era and reports of excavation investigation in 1970s verified that it was a temporary stair built by Japan and its meaning was given later. This research checked the scenery of Bulguksa Temple before Japanese colonial era and it is intended for basic data to conduct restoration or reconstruction project in the future.

• The Journal of Korean Society for Radiation Therapy
• /
• v.18 no.2
• /
• pp.81-87
• /
• 2006

Purpose: Few researches have been peformed on the dose distribution of the moving organ for radiotherapy so far. In order to simulate the organ motion caused by respiratory function, multipurpose phantom and moving device was used and dosimetric measurements for dose distribution of the moving organs were conducted in this study. The purpose of our study was to evaluate how dose distributions are changed due to respiratory motion. Materials and Methods: A multipurpose phantom and a moving device were developed for the measurement of the dose distribution of the moving organ due to respiratory function. Acryl chosen design of the phantom was considered the most obvious choice for phantom material. For construction of the phantom, we used acryl and cork with density of $1.14g/cm^3,\;0.32g/cm^3$ respectively. Acryl and cork slab in the phantom were used to simulate the normal organ and lung respectively. The moving phantom system was composed of moving device, moving control system, and acryl and cork phantom. Gafchromic film and EDR2 film were used to measure dose ditrbutions. The moving device system may be driven by two directional step motors and able to perform 2 dimensional movements (x, z axis), but only 1 dimensional movement(z axis) was used for this study. Results: Larger penumbra was shown in the cork phantom than in the acryl phantom. The dose profile and isodose curve of Gafchromic EBT film were not uniform since the film has small optical density responding to the dose. As the organ motion was increased, the blurrings in penumbra, flatness, and symmetry were increased. Most of measurements of dose distrbutions, Gafchromic EBT film has poor flatness and symmetry than EDR2 film, but both penumbra distributions were more or less comparable. Conclusion: The Gafchromic EBT film is more useful as it does not need development and more radiation dose could be exposed than EDR2 film without losing film characteristics. But as response of the optical density of Gafchromic EBT film to dose is low, beam profiles have more fluctuation at Gafchromic EBT. If the multipurpose phantom and moving device are used for treatment Q.A, and its corrections are made, treatment quality should be improved for the moving organs.

• Korean Chemical Engineering Research
• /
• v.47 no.6
• /
• pp.762-767
• /
• 2009

In this study, the feasibility of using vegetable oil extracted from tropical crop seed as a biodiesel feedstock was investigated by producing biodiesel and analysing the quality parameters as a transport fuel. In order to produce biodiesel efficiently, two step reaction process(pre-treatment and transesterificaion) was required because the tropical crop oil have a high content of free fatty acids. To determine the suitable acid catalyst for the pre-esterification, three kinds of acid catalysts were tested and sulfuric acid was identified as the best catalyst. After constructing the experimental matrix based on RSM and analysing the statistical data, the optimal pre-treatment conditions were determined to be 26.7% of methanol and 0.982% of sulfuric acid. Trans-esterification experiments of the pre-esterified oil based on RSM were carried out, then discovered 1.24% of KOH catalyst and 22.76% of methanol as the optimal trans-esterification conditions. However, the quantity of KOH was higher than the previously established KOH concentration of our team. So, we carried out supplemental experiment to determine the quantity of catalyst and methanol. As a result, the optimal transesterification conditions were determined to be 0.8% of KOH and 16.13% of methanol. After trans-esterification of tropical crop oil, the produced biodiesel could meet the major quality standard specifications; 100.8% of FAME, 0.45 mgKOH/g of acid value, 0.00% of water, 0.04% of total glycerol, $4.041mm^2/s$ of kinematic viscosity(at $40^{\circ}C$).

• Sijohaknonchong
• /
• v.26
• /
• pp.25-54
• /
• 2007

This paper examines the literatherapy effects of Korea's oldest form of literature, Sijo, and its role in the future of literatherapy. Since literature is the expression of human emotions, and therapy is related to medicine, the two seem to have little in common, but they share the function of resolving conflicts. The effectiveness of literatherapy has only recently become a matter of discussion. However, literatherapy is greatly involved with the utility value of literature, and should be taken seriously. This research focused on the literatherapy function of the 16th-17th century Gangho-Sijo. Gangho-Sijo was created by literary men from the Sarim-school, who were removed from their posts in the government due to a massacre(Sawha) and rianly(Dangjaing), and spent most of their time away from politics. Their Sijo were mostly about life in retreat, and their mental state at that time. In relation to literatherapy, the mentality and attitudes of these scholars can be divided into three stages. The first is anxiety and depression, the second tranquility and harmony. and the third serenity. At the final stage, the scholars are liberated from worldly desires. Each of these phases hold the effect of literatherapy. The first stage can relate to 'theory of purgation', ISO-Prinsip, which is based on 'like cures like' which means to treat something with its own kind Fight fire with fire. The second step involves 'theory of purification', and by balancing his emotions, the scholar can achieve mental stability. In the final stage, literatherapy is acquired when the scholar expresses his emotions in a clarification(theory of clarification). At this phase, literatherapy finally has an effect, while the phase itself functions as literatherapy as well. The study of literatherapy is still at its early stages, thus has many limitations. However, literatherapy has bright prospects, and it is my hope that this report will be used as a reference for its further research.

• Korean Journal of Environment and Ecology
• /
• v.34 no.4
• /
• pp.334-344
• /
• 2020

A total of 24 families, 44 species, and 658 benthic macroinvertebrates were identified, and Ecdyonurus dracon Kluge (13%) was the dominant species in forested streams within the Yeonyeopsan (Mt.). A total of four habit categories (i.e., clingers (56%), burrowers (19%), swimmers (14%), and sprawlers (56%)) were identified, and clingers were the dominant habit at all survey points except point one (UP1). Habitat characteristics were depended on the hydraulic factors (e.g., flow velocity, depth, and substrates), water quality (e.g., DO and water temperature), and the habitat characteristics were differed in the riffle, which has a faster the flow velocity, compared by in the stagnant pool. In other words, in riffles, the clingers dominated in high flow velocity with the large maximum and median grain size for substrates in the habitats regardless of depth, but the burrowers and sprawlers were dominant in low flow velocity with the small maximum and median grain size for substrates in the habitats. Moreover, DO and flow velocity were in positive correlation (y = 0.6666x - 0.659, R² = 0.0851), and the habitat for burrowers was wider than that for sprawlers or clingers. The water depth was negatively correlated with water temperature (y = -26.397x + 283.87, R² = 0.1802) since the water temperature is more sensitive to insolation in shallow depth. pH was positively correlated with water temperature. The investigation of the habitat characteristics by separating the relations between pH and DO in upstream and downstream showed the low pH and high DO in the upstream with a high crown density of 68%, regardless of community composition. On the other hand, high pH and low DO in the downstream with a relatively low crown density of 51%. It was considered that the riparian forest played a role in suppressing the growth of attached algae and the controlling water temperature in headwater streams. Our findings identified the habitat characteristics of benthic macroinvertebrates in a headwater stream. We expected that the finding can provide reference data for suggesting conservation and management plans in a headwater stream and increasing academic value.

• Progress in Medical Physics
• /
• v.23 no.1
• /
• pp.33-41
• /
• 2012

For applying the quality assurance (QA) of volumetric modulated arc therapy (VMAT) introduced in Eulji Hospital, we classify it into three different QA steps, treatment planning QA, pretreatment delivering QA, and treatment verifying QA. These steps are based on the existing intensity modulated radiation therapy (IMRT) QA that is currently used in our hospital. In each QA step, the evaluated items that are from QA program are configured and documented. In this study, QA program is not only applied to actual patient treatment, but also evaluated to establish a reference of clinical acceptance in pretreatment delivering QA. As a result, the confidence limits (CLs) in the measurements for the high-dose and low-dose regions are similar to the conventional IMRT level, and the clinical acceptance references in our hospital are determined to be 3 to 5% for the high-dose and the low-dose regions, respectively. Due to the characteristics of VMAT, evaluation of the intensity map was carried out using an ArcCheck device that was able to measure the intensity map in all directions, $360^{\circ}$. With a couple of dosimetric devices, the gamma index was evaluated and analyzed. The results were similar to the result of individual intensity maps in IMRT. Mapcheck, which is a 2-dimensional (2D) array device, was used to display the isodose distributions and gave very excellent local CL results. Thus, in our hospital, the acceptance references used in practical clinical application for the intensity maps of $360^{\circ}$ directions and the coronal isodose distributions were determined to be 93% and 95%, respectively. To reduce arbitrary uncertainties and system errors, we had to evaluate the local CLs by using a phantom and to cooperate with multiple organizations to participate in this evaluation. In addition, we had to evaluate the local CLs by dividing them into different sections about the patient treatment points in practical clinics.

• Applied Chemistry for Engineering
• /
• v.8 no.4
• /
• pp.560-567
• /
• 1997

A new approach to obtain stable $W_1/O/W_2$ multiple emulsions has been studied ; The basis of the interfacial interaction between a PCL-PEO-PCL triblock copolymer and a lipophilic emulsifier in the dispersed oil phase was examined. $W_1/O/W_2$ multiple emulsions were prepared by the two-step method. Arlacel P-l35 was used as a liphophilic emulsifier and Synperonic PE/F 127 as a hydrophilic one. Eutanol-G was used as an oil phase. NaCl was encapsulated within the multiple emulsion droplets as the internal marker and its release rate studies were carried out. The suability of the multiple emulsions have been assessed by measuring Separation Ratios(%) and microscopic observations. The release of NaCl was significantly reduced in $W_1/O/W_2$ multiple emulsions containing PCL-PEO-PCL triblock copolymer(2k-4k-2k or 6k-4k-6k) in the oil phase. It may be concluded that the copolymer and the emulsifier form effective interfacial complex to enhance stability and to control the release rate. The effective diffusion coefficients of the NaCl were estimated as $2.64{\times}10^{-15}s$and $3.23{\times}10^{-16}gcm^2/s$ for the $W_1/O/W_2$ multiple emulsion containing 1.2 wt % of PCL-PEO-PCL triblock copolymers with compositions of 2k-4k-2k and 6k-4k-2k, respectively. The rate of release decreased with the increase of the initial concentration of NaCl. The results were examined in view of Higuchi mechanism. A kinetic model which is similar to the model for release of dispersed drugs from a polymeric matrix was found to be suitable for the release of NaCl from $W_1/O/W_2$ multiple emulsions.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.32 no.1
• /
• pp.75-88
• /
• 2005

Ameloblastoma is the most commonly occurring odontogenic tumor in oral cavity. Although most are benign epithelial neoplasm, they are generally considered to be locally aggressive and destructive, exhibiting a high rate of recurrence. The biological behavior of this neoplasm is a slowly growing, locally invasive tumor without metastasis, therefore malignant neoplasm, changed its histological appearance to carcinoma or showed distant metastasis, is only defined clinically. In this study, we identified the differentially expressed genes(DEGs) in stages under benign or malignant ameloblastoma compared with normal patient using ordered differential display(ODD) reverse transcription(RT)-PCR and $GeneFishing^{TM}$ technology. ODD RT-PCR is rather effective when the investigation of samples containing very small amounts of total RNA must be accomplished. ODD RT-PCR used the means of amplification with anchored T-primer and adaptor specific primer. bearing definite two bases at their 3' ends and so this method could display differential 3'-expressed sequence taqs(ESTs) patterns without using full-length cDNAs. Compared with standard differential display, ODD RT-PCR is more simple and have enough sensitivity to search for molecular markers by comparing gene expression profiles, However, this method required much effort and skill to perform. $GeneFishing^{TM}$ modified from DD-PCR is an improved method for detecting differentially expressed genes in two or more related samples. This two step RT-PCR method uses a constant reverse primer(anchor ACP-T) to prime the RT reaction and arbitrary primer pairs(annealing control primers, ACPs) during PCR. Because of high annealing specificity of ACPs than ODD RT-PCR, the application of $GeneFishing^{TM}$ to DEG discovery generates reproducible, authentic, and long(100bp to 2kb) PCR products that are detectable on agarose gels. Consequently, various DEGs observed differential expression levels on agarose gels were isolated from normal, benign, and malignant tissues using these methods. The expression patterns of the some isolated DEGs through ODD RT-PCR and $GeneFishing^{TM}$ were confirmed by Northern blot analysis and RT-PCR. The results showed that these identified DEGs were implicated in ameloblastoma neoplasm processes. Therefore, the identified DEGs will be further studied in order to be applied in candidate selection for marker as an early diagnosis during ameloblastoma neoplasm processes.