• Clinical and Experimental Reproductive Medicine
• /
• v.37 no.4
• /
• pp.329-338
• /
• 2010

Objective: This study was carried out to know whether cryopreservation of sibling 2PN zygotes could increase the cumulative delivery rates in the patients who had less than 10 fertilized zygotes. Methods: A retrospective analysis was performed in 138 in vitro fertilization-embryo transfer (IVF-ET) cycles with less than 10 fertilized zygotes during January 2003 to December 2007 in Cheil General Hospital. These cycles were divided into two groups. In Group I (n=86), all fertilized embryos were cultured to transfer on day 3 without cryopreserved embryos at the 2PN stage. In Group II (n=52), among fertilized zygotes, some sibling zygotes were frozen at the 2PN stage, the remainder were cultured to transfer. Clinical outcomes in fresh ET cycles and cumulative ongoing pregnancy rates after subsequent frozen-thawed (FT)-ET cycles were compared. Results: There were no significant differences in female mean age, number of retrieved oocytes and total fertilized embryos between two groups, Number of cultured embryos was significantly lower in Group II ($5.2{\pm}0.5$) than in Group I ($8.4{\pm}0.7$) (p<0.01). Also, number of transferred embryos was significantly lower in Group II ($3.3{\pm}0.6$) compared with Group I ($3.6{\pm}0.6$) (p<0.01). ${\beta}$-hCG positive rates and delivery rates (51.2 vs. 46.2 % and 41.9 vs. 34.6 %, respectively) after fresh ET were slightly higher in Group I than in Group II. However, the differences were not statistically significant. Also, the cumulative delivery rates after subsequent FT-ET cycles were not significantly different between Group I (48.8%) and Group II (50.0%). Conclusion: This study showed that cryopreservation of sibling 2PN zygotes from patients who had less than 10 zygotes in the fresh ET cycles did not increase cumulative delivery outcomes. But, it could provide an alternative choice for patients due to offering more chance for embryo transfers if pregnancy was failed in fresh IVF-ET cycles.

• The Korean Journal of Mycology
• /
• v.35 no.2
• /
• pp.85-95
• /
• 2007

This study was carried out to investigate the physiological activities of the ethanol extract from Gymnopilus spectabilis mycelium (EGM) and of the supernatant obtained from fermentation broth (SGB). The contents of polysaccharides, phenol compounds and total ${\beta}-glucans$ of EGM were found to be 80.14%, 3.5 mg/ml and 5.91%, respectively and those for SGB were 78.68%, 3.32 mg/ml and 3.28%, respectively. Both EGM and SGB exhibited dose-dependent nitrate-scavenging abilities at pH 1.2. In addition, both EGM and SGB on the autoxidation rate of the linoleic acid demonstrated powerful antioxidant activities at 1 mg/ml level. With respect to fibrolytic activity, EGM showed 1,180 unit/g, which was the same activity as streptokinase, while SGB was 1,011 unit/g. The angiotensin converting enzyme inhibition activity of EMG determined by both the normal and pretreatment methods were estimated to be 8.2% and 10.2%, respectively. However, SGB showed no corresponding activity. The growth inhibitory effects of EGM on AGS, A549, HeLa and NCTC cells were over 58.88%, respectively. And the growth inhibitory effects of the SGB on HeLa and NCTC cells were 44.92 and 76.76%, respectively. Also, EGM and SGB activated the components of the alternative complement pathway from 51 and 62% at the concentration of 100 mg/ml, The xanthine oxidase inhibition activities of EGM and SGB (1 mg/ml) were 9.53 and 16.92%, respectively.

• Korean Journal of Optics and Photonics
• /
• v.27 no.1
• /
• pp.1-17
• /
• 2016

Over the past two decades, fiber-based lasers have made remarkable progress, now having reached power levels exceeding kilowatts and drawing a huge amount of attention from academy and industry as a replacement technology for bulk lasers. In this paper we review the significant factors that have led to the progress of fiber lasers, such as gain-fiber regimes based on ytterbium-doped silica, optical pumping schemes through the combination of laser diodes and double-clad fiber geometries, and tandem schemes for minimizing quantum defects. Furthermore, we discuss various power-limitation issues that are expected to incur with respect to the ultimate power scaling of fiber lasers, such as efficiency degradation, thermal hazard, and system-instability growth in fiber lasers, and various relevant methods to alleviate the aforementioned issues. This discussion includes fiber nonlinear effects, fiber damage, and modal-instability issues, which become more significant as the power level is scaled up. In addition, we also review beam-combining techniques, which are currently receiving a lot of attention as an alternative solution to the power-scaling limitation of high-power fiber lasers. In particular, we focus more on the discussion of the schematics of a spectral beam-combining system and their individual requirements. Finally, we discuss prospects for the future development of fiber laser technologies, for them to leap forward from where they are now, and to continue to advance in terms of their power scalability.

• Journal of Applied Biological Chemistry
• /
• v.61 no.3
• /
• pp.297-304
• /
• 2018

Coptis chinensis is used in oriental medicine for soothing, anti-inflammation, antimicrobial and antipyretic properties, and its main ingredient berberine is known to have strong antibacterial activity. In this study, we investigated the anti-microbial effect of hot water extract of Coptis chinensis (CW) on skin related microorganism and the airborne microbe, the antifungal effects of fungi, which are frequently detected in residential environments. CW showed antibacterial effect against Propionibacterium acnes, Staphylococcus aureus and Staphylococcus epidermidis, against the airborne microbe, which was collected in four different places. At the concentration of 100 mg/mL, the antimicrobial activity continued for 42 days, showed heat stability without change in the antimicrobial activity even after heat treatment. The MIC and MBC of CW against S. aureus was 0.03, 0.05 mg/mL, against S. epidermidis was 0.50, 0.75 mg/mL and against P. acne was 0.10, 0.15 mg/mL. As a result of measuring the MIC of four kinds of fungi with high detection frequency in the surrounding environment, Gliocladium virens was 65 mg/mL by determined as MIC which can inhibit one hundred percent of mycelial growth. The concentration 90 mg/mL was determined as MIC against Aureobasidium pullulans and 100 mg/mL against Penicilium pinophilum and Chaetomium globosum. CW was considered a safe extract that showed no irritation even in the ocular mucous membrane irritation evaluation test, a patch test. Therefore, these results suggest that Coptis chinensis has antimicrobial, antifungal and safety on human body and can be applied to the development of materials for cosmetic and residential environment industries.

• Journal of Korean Orthopaedic Sports Medicine
• /
• v.10 no.1
• /
• pp.18-26
• /
• 2011

Purpose: This study is to compare the clinical results of ACL reconstruction between three groups using hamstring tendon autograft, mixed and tibialis tendon allograft. Materials and Methods: Between August 2003 and August 2008, we analyzed 169 cases of ACL reconstruction, 66 cases used hamstring tendon autograft, 42 cases used mixed graft and 61 cases used tibialis tendon allograft, with a minimum follow-up of 12 months. For the clinical evaluation, we evaluated the Lysholm score, Telos stress test device and IKDC score. Results: The average side to side difference in Telos stress test decreased from $7.5{\pm}1.0$ mm to $1.6{\pm}1.0$ mm in autograft group, from $7.6{\pm}1.1$ mm to $1.4{\pm}1.1$ mm in mixed graft group and from $7.4{\pm}1.3$ mm to $2.5{\pm}1.3$ mm in allograft group. The average Lysholm knee score improved from 58.6 to 92.3 in autograft group, from 60.6 to 92.6 in mixed graft group and from 55.3 to 91.5 in allograft group. There was no significant difference between three groups in clinical results. At second look arthroscopy, tension of ligament and synovial coverage were good result in autograft and mixed graft than allograft group. Conclusion: All hamstring tendon autograft, mixed graft and tibialis tendon allograft groups showed satisfactory clinical results, with no significant difference in outcomes between the groups. Both hamstring tendon autograft and mixed graft showed good synovial coverage in second look arthroscopy. So mixed graft will be considered as good alternative in case of shorter or thin harvested hamstring tendon.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.21 no.12
• /
• pp.715-732
• /
• 2009

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2008. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends in thermal and fluid engineering have been surveyed in the categories of general fluid flow, fluid machinery and piping, new and renewable energy, and fire. Well-developed CFD technologies were widely applied in developing facilities and their systems. New research topics include fire, fuel cell, and solar energy. Research was mainly focused on flow distribution and optimization in the fields of fluid machinery and piping. Topics related to the development of fans and compressors had been popular, but were no longer investigated widely. Research papers on micro heat exchangers using nanofluids and micro pumps were also not presented during this period. There were some studies on thermal reliability and performance in the fields of new and renewable energy. Numerical simulations of smoke ventilation and the spread of fire were the main topics in the field of fire. (2) Research works on heat transfer presented in 2008 have been reviewed in the categories of heat transfer characteristics, industrial heat exchangers, and ground heat exchangers. Research on heat transfer characteristics included thermal transport in cryogenic vessels, dish solar collectors, radiative thermal reflectors, variable conductance heat pipes, and flow condensation and evaporation of refrigerants. In the area of industrial heat exchangers, examined are research on micro-channel plate heat exchangers, liquid cooled cold plates, fin-tube heat exchangers, and frost behavior of heat exchanger fins. Measurements on ground thermal conductivity and on the thermal diffusion characteristics of ground heat exchangers were reported. (3) In the field of refrigeration, many studies were presented on simultaneous heating and cooling heat pump systems. Switching between various operation modes and optimizing the refrigerant charge were considered in this research. Studies of heat pump systems using unutilized energy sources such as sewage water and river water were reported. Evaporative cooling was studied both theoretically and experimentally as a potential alternative to the conventional methods. (4) Research papers on building facilities have been reviewed and divided into studies on heat and cold sources, air conditioning and air cleaning, ventilation, automatic control of heat sources with piping systems, and sound reduction in hydraulic turbine dynamo rooms. In particular, considered were efficient and effective uses of energy resulting in reduced environmental pollution and operating costs. (5) In the field of building environments, many studies focused on health and comfort. Ventilation. system performance was considered to be important in improving indoor air conditions. Due to high oil prices, various tests were planned to examine building energy consumption and to cut life cycle costs.

• Journal of Korean Home Economics Education Association
• /
• v.30 no.1
• /
• pp.43-63
• /
• 2018

The purpose of this study is to examine the various contexts affecting life culture through practical reasoning process and to select the goal and contents system of unification education in middle school home economics to form healthy unification community and to develop teaching and learning process. Based on the Unification Education Guidelines, Unification Education Pre-Study, Pre-Study on North Korean Defectors, and Analysis of the 2015 Revision Home Economics Curriculum in Korea, Goal and content system. Based on this, we developed a teaching and learning process and a student activity place applying practical reasoning process after extracting practical problems, and prepared a final development plan based on the results of two expert group evaluations. The results of this study are summarized as follows. First, the goal of unification education in the middle school home economics class is to 'Based on the social-cultural context, we develop the ability to cultivate healthy reunification by respecting the differences between the cultures of the two Koreas and discovering common values in a unified society and resolving practical issues in a unified society.'. Second, the content system of middle school home economics unification education was selected as the core theme of 'Unification Education Focused on the Living Culture'. The content elements were comprehending the socio - cultural context that affects the life culture of the two Koreas, Related language, maintenance of diversity of dietary culture in each region including North Korean food, social norms and attire, correct housing value and common living etiquette. Based on the goals of unification education in the middle school home school curriculum, we selected practical issues as 'What should we do to create a healthy unified community?'. Third, the teaching and learning process of unification education in junior high school home economics education is to recognize the problem of unification, to analyze the factors affecting the life culture of the two Koreas, to grasp the effect of the action and the ripple effects, to select alternative methods, And 4 subjects for 8 teaching learning course plan, and 35 teaching materials.

• The korean journal of orthodontics
• /
• v.38 no.4
• /
• pp.275-282
• /
• 2008

Objective: The purpose of this study was to investigate the effect of using laser for ceramic bracket bonding of porcelain surfaces and to compare it with conventional treatment of porcelain surfaces. Methods: Ninety feldspathic porcelain specimens were divided into 9 groups of 10, with each group having different surface treatments performed. Surface treatment groups were orthophosphoric acid, orthophosphoric acid with silane, hydrofluoric acid, hydrofluoric acid with silane, sandblasted, sandblasted with silane, laser etched, laser etched with silane, and glazed surface served as a control group. In the laser etched groups, the specimens were irradiated with 2-watt superpulse carbon dioxide ($CO_2$) laser for 20 seconds. Ceramic brackets were bonded with light-cure composite resin and all specimens were stored in water at $37^{\circ}C$ for 24 hours. Shear bond strength was determined in megapascals (MPa) by shear test at 1 mm/minute crosshead speed and the failure pattern was assessed. For statistical analysis, one-way ANOVA and tukey test were used. Results: Statistical analysis showed significant differences between the groups. The HFA + S group showed the highest mean shear bond strength ($13.92{\pm}1.94\;MPa$). This was followed by SB + S ($10.16\;{\pm}\;1.27\;MPa$), HFA ($10.09\;{\pm}\;1.07\;MPa$), L + S ($8.25\;{\pm}\;1.24\;MPa$), L ($7.86\;{\pm}\;0.96\;MPa$), OFA + S ($7.22\;{\pm}\;1.09\;MPa$), SB ($3.41\;{\pm}\;0.37\;MPa$), OFA ($2.81\;{\pm}\;0.37\;MPa$), G ($2.46\;{\pm}\;1.36\;MPa$), Bond failure patterns of HFA and silane groups, except L + S, were cohesive modes in porcelain while adhesive failure was observed in the control group and the rest of the groups. Conclusions : A 2-watt superpulse $CO_2$ laser etching of porcelain surfaces can provide a satisfactory result for porcelain surface treatment for ceramic bracket bonding. Laser irradiation may be an alternative conditioning method for the treatment of porcelain surfaces.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.19 no.1
• /
• pp.94-131
• /
• 2007

A review on the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering in 2004 and 2005 has been done. Focus has been put on current status of research in the aspect of heating, cooling, air-conditioning, ventilation, sanitation and building environment. The conclusions are as follows. (1) Most of fundamental studies on fluid flow were related with heat transportation of facilities. Drop formation and rivulet flow on solid surfaces were interesting topics related with condensation augmentation. Research on micro environment considering flow, heat, humidity was also interesting for comfortable living environment. It can be extended considering biological aspects. Development of fans and blowers of high performance and low noise were continuing topics. Well developed CFD and flow visualization(PIV, PTV and LDV methods) technologies were widely applied for developing facilities and their systems. (2) The research trends of the previous two yews are surveyed as groups of natural convection, forced convection, electronic cooling, heat transfer enhancement, frosting and defrosting, thermal properties, etc. New research topics introduced include natural convection heat transfer enhancement using nanofluid, supercritical cooling performance or oil miscibility of $CO_2$, enthalpy heat exchanger for heat recovery, heat transfer enhancement in a plate heat exchanger using fluid resonance. (3) The literature for the last two years($2004{\sim}2005$) is reviewed in the areas of heat pump, ice and water storage, cycle analysis and reused energy including geothermal, solar and unused energy). The research on cycle analysis and experiments for $CO_2$ was extensively carried out to replace the Ozone depleting and global warming refrigerants such as HFC and HCFC refrigerants. From the year of 2005, the Gas Engine Heat Pump(GHP) has been paid attention from the viewpoint of the gas cooling application. The heat pipe was focused on the performance improvement by the parametric analysis and the heat recovery applications. The storage systems were studied on the performance enhancement of the storage tank and cost analysis for heating and cooling applications. In the area of unused energy, the hybrid systems were extensively introduced and the life cycle cost analysis(LCCA) for the unused energy systems was also intensively carried out. (4) Recent studies of various refrigeration and air-conditioning systems have focused on the system performance and efficiency enhancement. Heat transfer characteristics during evaporation and condensation are investigated for several tube shapes and of alternative refrigerants including carbon dioxide. Efficiency of various compressors and expansion devices are also dealt with for better modeling and, in particular, performance improvement. Thermoelectric module and cooling systems are analyzed theoretically and experimentally. (5) According to the review of recent studies on ventilation systems, an appropriate ventilation systems including machenical and natural are required to satisfied the level of IAQ. Also, an recent studies on air-conditioning and absorption refrigeration systems, it has mainly focused on distribution and dehumidification of indoor air to improve the performance were carried out. (6) Based on a review of recent studies on indoor environment and building service systems, it is noticed that research issues have mainly focused on optimal thermal comfort, improvement of indoor air Quality and many innovative systems such as air-barrier type perimeter-less system with UFAC, radiant floor heating and cooling system and etc. New approaches are highlighted for improving indoor environmental condition as well as minimizing energy consumption, various activities of building control and operation strategy and energy performance analysis for economic evaluation.

• Korean Journal of Acupuncture
• /
• v.33 no.2
• /
• pp.67-74
• /
• 2016

Objectives : The Knee degenerative osteoarthritis patients are not satisfied with the conventional therapies of KDOA, which results in the use of alternative therapies. The miniscalpel acupuncture is effective in treating chronic soft tissue, releasing contractures. However, there is little scientific evidence supporting the use of miniscalpel acupuncture in knee degenerative osteoarthritis. This study was designed to obtain basic data for a further large-scale trial as well as provide information about the feasibility of miniscalpel acupuncture in knee degenerative osteoarthritis patients. Methods : We describe the protocol for a randomized controlled pilot clinical trial of 5 weeks duration. Twenty patients will be recruited and randomly allocated to two treatment groups: miniscalpel acupuncture treatment(experimental group); and acupuncture and electro-acupuncture treatment(control group). Miniscalpel acupuncture will be performed once with a 1-week interval for 3 weeks. Electro-acupuncture will be administered twice per week for a period of 3 weeks. The primary outcomes will be measured by visual analogue scale and range of motion. The secondary outcomes will be short-form McGill Pain Questionnaire and Western Ontario and McMaster Universities Osteoarthritis Index. Both primary and secondary outcomes will be measured at baseline and at 1, 2, 3 and 5 weeks(i.e. 2 weeks after treatment completion). Conclusions : This pilot study will provide a basic foundation for a future large-scale trial as well as information about the feasibility of miniscalpel acupuncture in knee degenerative osteoarthritis.