• Korean Journal of Clinical Laboratory Science
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• v.53 no.2
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• pp.158-164
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• 2021

Hypertriglyceridemia is the main risk factor for atherosclerosis. It is reported that triglyceride (TG) induces macrophage cell death, and is involved in the formation of plaques and development of atherosclerosis. We previously reported that TG-induced cell death of macrophages is mediated via pannexin-1 activation, which increases the extracellular ATP and subsequent increase in potassium efflux, thereby activating the caspase-2/caspase-1/apoptotic caspases, including the caspase-8 pathway. Contrarily, some studies have reported that caspase-8 is an upstream molecule of caspase-1 and caspase-2 in several cellular processes. Therefore, this study was undertaken to investigate whether caspase-8 influences its upstream molecules in TG-stimulated macrophage cell death. We first confirmed that caspase-8 induces caspase-3 activation and poly ADP-ribose polymerase (PARP) cleavage in TG-treated macrophages. Next, we determined that the inhibition of caspase-8 results in reduced caspase-1 and -2 activity, which are upstream molecules of caspase-8 in TG-induced cell death of macrophages. We also found that ATP treatment restores the caspase-8 inhibitor-induced caspase-2 activity, thereby implying that caspase-8 affects the upstream molecules responsible for increasing the extracellular ATP levels in TG-induced macrophage cell death. Taken together, these findings indicate that caspase-8 potentiates the TG-induced macrophage cell death by activating its upstream molecules.

• Particle and aerosol research
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• v.16 no.4
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• pp.107-117
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• 2020

Based on the airborne measurement results over a coal fired power plant and steel work in Dangjin city, SO2 emission amounts of each site are estimated (top-down emission). Airborne measurements were carried out on May-June and October-November 2019. The estimated SO2 emission in 2019 for the power plant was 1502.1 kg/hr and that for the steel work was 2850.5 kg/hr, higher as much as a factor of 2.5 and 2.0, respectively, than the emission amounts provided by both facilities (bottom-up emission). The outcomes strongly illustrates that well designed airborne observations can serve a quantitative diagnostic tool for bottom-up emission estimates. Further research direction to improve the reliability of the top-down emission estimates is suggested.

• The Mathematical Education
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• v.61 no.4
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• pp.521-537
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• 2022

The unprecedented COVID-19 pandemic has disrupted, interrupted, and changed the way we normally prepare our teacher candidates in teacher preparation programs. In this paper, we, two mathematics teacher educators (MTEs), reflect our own experiences in appropriating, transforming, reconstructing, and modifying our pedagogies of teacher education in making a transition from face-to-face to online environment during the COVID-19 pandemic. Using a collaborative self-study, we discussed issues, challenges, changes, opportunities, and innovations of teaching an elementary mathematics methods course in the online environment. Using a constant comparison method, we explored the following three themes: (1) using virtual manipulatives; (2) creating collaborative, interactive, and shared learning experiences for preservice teachers; and (3) making preservice teachers engaged in student thinking. These findings indicated that online teaching requires transformative knowledge for teacher educators. Transferring face-to-face to online is not a simple matter of putting the existing content to online; it should focus on pedagogical improvement in teaching mathematics rather than technology's sake or how it can be repurposed in a new online environment in a way that students' learning is optimized. The findings of this study provide implications for unpacking MTEs' technological pedagogical content knowledge (TPACK), creating collaborative learning experiences for preservice teachers, and designing a collaborative self-study between MTEs engaged in the community of professional learning.

• Journal of Appropriate Technology
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• v.6 no.2
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• pp.115-125
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• 2020

Housing issues such as mushrooming slums remain as chronic in most developing countries. Due to the state's restrained capacity, the housing-vulnerable's self-help approaches have been increasingly inevitable and vital for addressing the housing issues. However, there are still two challenges: securing good quality with economic efficiency, and climate change mitigation and adaptation. This study aims at doing an architectural experiment by developing and educating the production of eco-friendly interlocking stabilized soil bricks (ISSB) by employing vernacular materials and technologies for housing-vulnerable communities in Indonesia. In collaboration with a local architectural NGO, the study features a co-creation workshop in which 40 evicted households participate in the whole process. Soil analysis, mixed design, compression tests, and economic analysis are carried out. This paper illustrates that ISSB also has a high potential as an alternative to a burned brick or a cement block. The application of ISSB to self-help housing is expected to have socioeconomic and environmental effects, thereby facilitating the housing-vulnerable's self-help approaches and contributing to addressing the housing challenges in Indonesia.

• Journal of the Korean Wood Science and Technology
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• v.32 no.4
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• pp.58-65
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• 2004

This study was performed to investigate the protease activity from fruit body of Sarcodon aspratus and its features. The specific protease activity was increased with the increasing purification steps, 2.62 times by desalting, 17 times by CMC column chromatography, 113.8 times by DEAE-Sephadex A-50 column chromatography, and 728.3 times by Sephadex G-75 column chromatography. Proteases were identified as two different enzymes having different isoelectric points at pH 4.35 (its recovery rate 8%) and pH 4.7 (its recovery rate 3.5%). Those proteases were purified by 3,025 folds and 3,257 folds in terms of specific activity. Two proteases having different isoelectric points had similar enzymatic properties. This protease was estimated to be 43,000 daltons of molecular weights by SDS-PAGE. This protease with optimum pH 4 was almost stable in the pH range of 4~7. Optimal temperature of protease activity was 40 to 50℃, and the protease activity was completely inhibited at 70℃ for 30 min.

• Journal of the Korean Wood Science and Technology
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• v.32 no.5
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• pp.12-19
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• 2004

This study was performed to investigate the optimum condition of protease production from submerged culture of oak mushroom (Lentinula edodes, Sanlim No. 5) and its enzymatic features. Among several combinations of media, the combination of wheat bran, corn flour, water and corn oil (WB+CF+W+ CO) yielded 84.8 U/g of maximum protease activity. This combination of ingredients, in spite of not being particularly protein-rich in comparison to the other media, allowed for good growth of the fungus and maximal protease production. Comparison of different growth medium liquids indicated that demineralized water afforded the best growth of the fungus and the highest protease activity. Acetate buffer and acidified water negatively affected The protease production peaked around 72 hr of incubation, and decreased thereafter. The molecular weights of produced protease were about 45,000 by Sephadex G-75 chromatography. The pH optimum for protease activity was 4, while maximal activity incubated at 37℃ for 1 hr was observed between pH 4~6. The optimum temperature of this protease was 55℃, and the enzyme was active over a broad temperature range (30~60℃), indicating that this protease would be suitable for a wide range of applications where. different pH and temperature are necessary, such as digestive aids, food industry, beer and tannery industries.

• Journal of the Korean Wood Science and Technology
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• v.32 no.5
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• pp.39-44
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• 2004

This study was carried out to investigate the tenderizing effect of Neungi mushroom (Sarcodon aspratus) powder and its protease. The addition of Neungi mushroom powder and its protease enhanced water retention values (WRY) of meat. The WRY of meat was increased 26.8% by protease addition, compared to 13.8% WRV by sugar addition. This increase in WRY derived to the increase of water soluble fraction in the meat texture by hydrolysis of meat protein, and had the meat tenderized. Concerned to the meat tenderizing effect, the addition of Neungi mushroom powder and its protease have decreased of meat hardness and gave similar tenderizing effect, as compared to commercial tenderizer, papain. The decreasing rates of meat hardness were 51.6% of Neungi mushroom powder, 58.5% of its protease, and 563% of commercial tenderizer, papain. This tenderizing effect of protease attributed to the degradation of muscle fiber protein in meat, such as actin, myosin and connectin etc. The addition of Neungi mushroom to foods gives significant changes in food color, mainly decreasing lightness.

• The Korean Society of Law and Medicine
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• v.23 no.2
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• pp.67-96
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• 2022

"Aid in Dying" means that when a decision-making patient suffers from an incurable disease, a drug that can speed up death is prescribed by a doctor and used to lead to death. Since the suspension of life-sustaining treatment was institutionalized based on human dignity and patient autonomy, the question of whether assisted death can be legally justified in relation to the right to receive medical help to shorten one's life to die with dignity has recently been actively discussed. In Korea, since the suspension of life-sustaining treatment was institutionalized by the enactment of the Life-sustaining Treatment Decision Act in 2016, an amendment to the Life-sustaining Treatment Act was recently proposed to legalize Aid in Dying. The global trend is that human "Right to Die" is discussed in the division of life and death, from the suspension of life-sustaining treatment to assisted death, and again in the order of euthanasia. In this paper, we started discussing dignified death and institutionalized patients' right to self-determination, looked at the controversy in the United States, which legislated assisted death in many states since the 2000s, and analyzed the main contents of California's End of Life Option Act and the data after enforcement. The strict requirements for Aid in Dying, such as voluntary confirmation of patients' intentions and doctors' obligation to provide information, and the results of California's Aid in dying system, composed of relatively diverse races, were reviewed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.1
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• pp.10-18
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• 2022

With the increase in world trade through ships, the destruction of the marine ecosystem and socioeconomic damage due to invasive alien species (IAS) are continuously increasing. In particular, marine organisms attached on the hull surface and niche area increase the friction resistance of ships as well as the invasion of non-indigenous species, and causes a decrease in operational efficiency and an increase in GHG (Green House Gas) emissions. The International Maritime Organization (IMO) has recently begun revising guidelines for the control and management of ship's biofouling, and New Zealand and California in the United States are already regulating biofouling management under their own laws. This study investigated the management status of the submerged surface of ships and marine organisms attachments on five international ships entering South Korea, and analyzed species group and coverage (%) of biofouling communities to evaluate the LoF (Level of Fouling) rank. Macroflouling was observed on all ships surveyed, and specially, the adhesion of macro organisms in niche areas such as bow thruster, bilge keels and sea-chest gratings appeared to be at a serious level. This study proposed the management direction our country should take with regard to ship's biofouling and the improvement measures for evaluation of LoF rank and inspection methods of hull and niche ares.

• Journal of the Korean Geotechnical Society
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• v.23 no.2
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• pp.47-60
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• 2007

Conventional active surface wave measurements performed using a transient or continuous source are often limited in the maximum depth of penetration due to the difficulty of generating low-frequency energy with reasonably portable sources. This limitation may inhibit accurate seismic site response calculations because of the inability to define deeper subsurface structure. By measuring surface wave generated by passive sources including microtremors and cultural noise, it is possible to overcome this problem and develop soil stiffness profiles to much larger depth. Reliability of dispersion estimates from the passive surface wave measurements is critical to present reliable shear wave velocity profiles and can be improved by the measurements and analyses of passive surface waves based on correct understanding of systematic errors included in passive dispersion data. In this study, the systematic errors caused by poor wavenumber resolution and energy leakage into sidelobes in passive tests are mainly explored. Recommendations for reliable passive surface wave measurements and dispersion estimates are presented and illustrated at a site in San Jose, California, U.S.