• Animal Bioscience
• /
• v.37 no.6
• /
• pp.1021-1030
• /
• 2024

Objective: R-loops are DNA:RNA triplex hybrids, and their metabolism is tightly regulated by transcriptional regulation, DNA damage response, and chromatin structure dynamics. R-loop homeostasis is dynamically regulated and closely associated with gene transcription in mouse zygotes. However, the factors responsible for regulating these dynamic changes in the R-loops of fertilized mouse eggs have not yet been investigated. This study examined the functions of candidate factors that interact with R-loops during zygotic gene activation. Methods: In this study, we used publicly available next-generation sequencing datasets, including low-input ribosome profiling analysis and polymerase II chromatin immunoprecipitation-sequencing (ChIP-seq), to identify potential regulators of R-loop dynamics in zygotes. These datasets were downloaded, reanalyzed, and compared with mass spectrometry data to identify candidate factors involved in regulating R-loop dynamics. To validate the functions of these candidate factors, we treated mouse zygotes with chemical inhibitors using in vitro fertilization. Immunofluorescence with an anti-R-loop antibody was then performed to quantify changes in R-loop metabolism. Results: We identified DEAD-box-5 (DDX5) and histone deacetylase-2 (HDAC2) as candidates that potentially regulate R-loop metabolism in oocytes, zygotes and two-cell embryos based on change of their gene translation. Our analysis revealed that the DDX5 inhibition of activity led to decreased R-loop accumulation in pronuclei, indicating its involvement in regulating R-loop dynamics. However, the inhibition of histone deacetylase-2 activity did not significantly affect R-loop levels in pronuclei. Conclusion: These findings suggest that dynamic changes in R-loops during mouse zygote development are likely regulated by RNA helicases, particularly DDX5, in conjunction with transcriptional processes. Our study provides compelling evidence for the involvement of these factors in regulating R-loop dynamics during early embryonic development.

• Korean Journal of Radiology
• /
• v.20 no.4
• /
• pp.621-630
• /
• 2019

Objective: To study the prevalence and clinical characteristics of decreased myocardial blood flow (MBF) quantified by dynamic computed tomography (CT) myocardial perfusion imaging (MPI) in symptomatic patients without in-stent restenosis. Materials and Methods: Thirty-seven (mean age, 71.3 ± 10 years; age range, 48-88 years; 31 males, 6 females) consecutive symptomatic patients with patent coronary stents and without obstructive de novo lesions were prospectively enrolled to undergo dynamic CT-MPI using a third-generation dual-source CT scanner. The shuttle-mode acquisition technique was used to image the complete left ventricle. A bolus of contrast media (50 mL; iopromide, 370 mg iodine/mL) was injected into the antecubital vein at a rate of 6 mL/s, followed by a 40-mL saline flush. The mean MBF value and other quantitative parameters were measured for each segment of both stented-vessel territories and reference territories. The MBF_ratio was defined as the ratio of the mean MBF value of the whole stent-vessel territory to that of the whole reference territory. An MBF_ratio of 0.85 was used as the cut-off value to distinguish hypoperfused from non-hypoperfused segments. Results: A total of 629 segments of 37 patients were ultimately included for analysis. The mean effective dose of dynamic CT-MPI was 3.1 ± 1.2 mSv (range, 1.7-6.3 mSv). The mean MBF of stent-vessel territories was decreased in 19 lesions and 81 segments. Compared to stent-vessel territories without hypoperfusion, the mean MBF and myocardial blood volume were markedly lower in hypoperfused stent-vessel territories (77.5 ± 16.6 mL/100 mL/min vs. 140.4 ± 24.1 mL/100 mL/min [p < 0.001] and 6.4 ± 3.7 mL/100 mL vs. 11.5 ± 4 mL/100 mL [p < 0.001, respectively]). Myocardial hypoperfusion in stentvessel territories was present in 48.6% (18/37) of patients. None of clinical parameters differed statistically significantly between hypoperfusion and non-hypoperfusion subgroups. Conclusion: Decreased MBF is commonly present in patients who are symptomatic after percutaneous coronary intervention, despite patent stents and can be detected by dynamic CT-MPI using a low radiation dose.

• Journal of Korean Society of Environmental Engineers
• /
• v.38 no.1
• /
• pp.14-24
• /
• 2016

Information on the lists of pollutants from industrial wastewater discharge are essential not only to specify the key pollutants to be managed in permission process but to design the treatment facilities by the dischargers. In this study, wastewater quality analysis was conducted for three industrial categories including the specified hazardous water pollutants. The general description of the wastewater occurrence, major sources, treatment facilities are also investigated to obtain integrated database on the pollutant inventories for the industrial categories. In addition Based on the analysis of raw wastewater and final effluent, the detected pollutant items are confirmed by analyzing their presence in the raw or supplement materials, the potential of formation as byproducts, and the possibility of inclusion as impurities. The three industrial categories include petrochemical basic compounds, basic organic compounds, and thermal power generation. The water pollutants emitted from petrochemical basic compound manufacturing facilities are 31 items including 16 specified hazardous water pollutants. Basic organic compound manufacturing facilities discharge 30 kinds of pollutants including 14 specified hazardous water pollutants. Thermal power generation facilities emit 20 pollutants, 8 specified hazardous water pollutants among them. These substances were decided as emission inventories of water pollutants finally through the probability evaluation. The compounds detected for each categories are screened through investigation on the possible causes of their occurrence and confirmed as the final water pollutant inventories.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.44 no.3
• /
• pp.347-355
• /
• 2015

Oxidative stress is one of the key mechanisms involved in neuronal damage. Neuroprotective effects and underlying mechanisms of action of several wild vegetables, Cirsium setidens (CS), Pleurospermum kamtschaticumin (PK), and Allium victorials (AV), against oxidative stress induced by hydrogen peroxide in SK-N-SH cells were investigated. CS and AV up to $400{\mu}g/mL$ showed no detectable effects on cell viability of human SK-N-SH neuro-blastoma cells compared with control. Incubation of SK-N-SH cells with hydrogen peroxide resulted in significant induction of cell death and reaction oxygen species (ROS) production, whereas treatment of cells with CS and AV significantly reduced cell death and ROS production, respectively. Among the wild vegetables tested, CS and PK showed more effective DPPH radical scavenging activity than AV, whereas PK showed strong cytotoxicity in SK-N-SH cells compared with the control. CS showed much higher inhibitory effects on cell death and ROS generation against oxidative stress than AV. Thus, CS was selected for subsequent experiments. Ethyl acetate (EA), hexane, butanol, aqueous, and chloroform extracts from CS significantly inhibited cell death and ROS generation in SK-N-SH cells induced by oxidative stress. EA extract from CS (CS-EA) showed the highest DPPH radical-scavenging activity, intra-cellular ROS-scavenging activity, and neuroprotective effects. CS-EA attenuated apoptosis signal-regulating p38 activation by inhibiting phosphorylation. The findings suggest that CS-EA protects neuronal cells through antioxidant activity and inhibition of phosphorylation of p38 in brain neural cells.

• Journal of Energy Engineering
• /
• v.23 no.4
• /
• pp.61-72
• /
• 2014

This paper analyzed transition pathways toward a low carbon society in Korea to meet global $2^{\circ}C$ climate target. Lower economic growth, industrial structure change, enhance of energy demand management, decarbonization of power sector, and replacement of low carbon fuel could reduce greenhouse gas (GHG) emission from fuel combustion in 2050 by 67% against in 2011, or by 74% against in BAU (Business-As-Usual). Lower economic growth contributes to 13% of cumulative emission reduction relative to BAU, industrial structure change 9%, enhance of energy demand management 72%, decarbonization of power sector 5% and replacement of low carbon fuel 1% respectively. Final energy consumption in 2050 needs to be reduced to 50% relative to 2011, or to 41% relative to BAU. Nuclear, coal and renewable energy represent 31%, 40%, 2% respectively among electricity generation in 2011, but 38%, 2%, 32% in 2050. CCS represents 23% of total generation in 2050. Emission intensity of electricity in 2050 was decreased to 19% relative to 2011, or to 24% relative to BAU. Primary energy in 2050 was decreased to 64% compared to 2011, or to 44% compared to BAU. Final energy consumption, primary energy supply and GHG emission from fuel combustion from 1990 to 2011 increased by 176%, 197%, 146%. Radical change from historical trend is required to transit toward a low carbon society by 2050. Appropriate economic growth, structural change to non-energy intensive industries, energy technology research, development and deployment (RD&D) in terms of enhancement of energy efficiency and low carbon energy supply technologies, and fuel change to electricity and renewable energy are key instruments.

• Journal of Energy Engineering
• /
• v.23 no.2
• /
• pp.125-148
• /
• 2014

This paper performs a historical analysis on the various factors contributing to the current carbon lock-in of Korean electricity industry by using techo-institutional complex. The possibilities of the industry's carbon lock-out toward more sustainable development are also investigated. It turns out that market, firm, consumer, and government factors are all responsible for the development of the carbon lock-in of Korean power industry; the Korean government consistently favoring large power plants based on the economy of scale; below-cost electricity tariff; inflation policy to suppress increases in power price; rapid demand growth in summer and winter seasons; rigidities of electricity tariff; and expansion of gas-fired and imported coal-fired large power plants. On the other hand, except for nuclear power generation and smart grid, environment laws and new and renewable energy laws are the other remaining factors contributing to the carbon lock-out. Considering three key points that Korea is an export-oriented economy, the generation mix is the most critical factor to decide the amounts of carbon emission in the power industry, and the share of industry and commercial power consumption is over 85%, it is unlikely that Korea will achieve the carbon lock-out of power industry in the near future. Therefore, there are needs for more integrated approaches from market, firm, consumer, and government all together in order to achieve the carbon lock-out in the electricity industry. Firstly, from the market perspective, it is necessary to persue more active new and renewable energy penetration and to guarantee consumer choices by mitigating the incumbent's monopoly power as in the OECD countries. Secondly, from the firm perspective, the promotion of distributed energy system is urgent, which includes new and renewable resources and demand resources. Thirdly, from the consumer perspective, more green choices in the power tariff and customer awareness on the carbon lock-out are needed. Lastly, the government shall urgently improve power planning frameworks to include the various externalities that were not properly reflected in the past such as environmental and social conflict costs.

• Journal of Environmental Impact Assessment
• /
• v.32 no.1
• /
• pp.1-14
• /
• 2023

When carrying out development projects around Ardeidae breeding habitats, we intend to devise a plan for sustainable coexistence by presenting measures to select and reduce key evaluation items so that conflicts can be prevented in advance at the environmental impact assessment stage. The results of the study are as follows. The main evaluation items are animal and plant items for preservation of Ardeidae breeding habitats and odor and noise items that can evaluate the effects of odors and noise in Ardeidae breeding habitats. First, the scope of the survey in animals and plants categories is not limited to legal guardian species, but includes egrets breeding and feeding grounds corresponding to major species breeding grounds and migratory birds, and preservation measures are established according to the reduction of the area of breeding and feeding grounds. Second, in the odor category, the irradiation period includes the period when the odor generation is the highest from the end of June to the end of July. The odor evaluation standard is based on the complex odor discharge standard, which is a concentration regulation, and the odor concentration felt by humans shall be 2 to 5OU/m³ and the frequency shall be 2% or less. Third, in the noise category, the timing of the survey is measured every month from May to August, including when the sound of egrets and young birds is combined to maximize noise generation. Since the noise of Ardeidae, a bird in summer, occurs only for a certain period of time, measures are taken to reduce noise by securing separation distances, securing buffer green areas, and installing construction rather than installing artificial structures such as soundproof walls. In order for existing Ardeidae breeding sites to maintain an appropriate density of populations and not move populations elsewhere, it is necessary to manage nesting tree and maintain stable habitat quantity and quality.

• Journal of Intelligence and Information Systems
• /
• v.22 no.4
• /
• pp.247-264
• /
• 2016

With the rapid acceleration of low-birth rate and population aging, the employment of the neglected groups of people including the middle aged class is a crucial issue in South Korea. In particular, in the 2010s, the number of the middle aged who want to find a new job after retirement age is significantly increasing with the arrival of the retirement time of the baby boom generation (born 1955-1963). Despite the importance of matching jobs to this emerging middle aged class, private job portals as well as the Korean government do not provide any online job service tailored for them. A gigantic amount of job information is available online; however, the current recruiting systems do not meet the demand of the middle aged class as their primary targets are young workers. We are in dire need of a specially designed recruiting system for the middle aged. Meanwhile, when users are searching the desired occupations on the Worknet website, provided by the Korean Ministry of Employment and Labor, users are experiencing discomfort to search for similar jobs because Worknet is providing filtered search results on the basis of exact matches of a preferred job code. Besides, according to our Worknet data analysis, only about 24% of job seekers had landed on a job position consistent with their initial preferred job code while the rest had landed on a position different from their initial preference. To improve the situation, particularly for the middle aged class, we investigate a soft job matching technique by performing the following: 1) we review a user behavior logs of Worknet, which is a public job recruiting system set up by the Korean government and point out key system design implications for the middle aged. Specifically, we analyze the job postings that include preferential tags for the middle aged in order to disclose what types of jobs are in favor of the middle aged; 2) we develope a new occupation classification scheme for the middle aged, Korea Occupation Classification for the Middle-aged (KOCM), based on the similarity between jobs by reorganizing and modifying a general occupation classification scheme. When viewed from the perspective of job placement, an occupation classification scheme is a way to connect the enterprises and job seekers and a basic mechanism for job placement. The key features of KOCM include establishing the Simple Labor category, which is the most requested category by enterprises; and 3) we design MOMA (Middle-aged Occupation Matching Algorithm), which is a hybrid job matching algorithm comprising constraint-based reasoning and case-based reasoning. MOMA incorporates KOCM to expand query to search similar jobs in the database. MOMA utilizes cosine similarity between user requirement and job posting to rank a set of postings in terms of preferred job code, salary, distance, and job type. The developed system using MOMA demonstrates about 20 times of improvement over the hard matching performance. In implementing the algorithm for a web-based application of recruiting system for the middle aged, we also considered the usability issue of making the system easier to use, which is especially important for this particular class of users. That is, we wanted to improve the usability of the system during the job search process for the middle aged users by asking to enter only a few simple and core pieces of information such as preferred job (job code), salary, and (allowable) distance to the working place, enabling the middle aged to find a job suitable to their needs efficiently. The Web site implemented with MOMA should be able to contribute to improving job search of the middle aged class. We also expect the overall approach to be applicable to other groups of people for the improvement of job matching results.

• Korean Journal of Remote Sensing
• /
• v.37 no.5_1
• /
• pp.1029-1042
• /
• 2021

As part of the next-generation Compact Advanced Satellite 500 (CAS500) project, CAS500-4 is scheduled to be launched in 2025 focusing on the remote sensing of agriculture and forestry. To obtain quantitative information on vegetation from satellite images, it is necessary to acquire surface reflectance through atmospheric correction. Thus, it is essential to develop an atmospheric correction method suitable for CAS500-4. Since the absorption and scattering characteristics in the atmosphere vary depending on the wavelength, it is needed to analyze the sensitivity of atmospheric correction parameters such as aerosol optical depth (AOD) and water vapor (WV) considering the wavelengths of CAS500-4. In addition, as CAS500-4 has only five channels (blue, green, red, red edge, and near-infrared), making it difficult to directly calculate key parameters for atmospheric correction, external parameter data should be used. Therefore, thisstudy performed a sensitivity analysis of the key parameters (AOD, WV, and O₃) using the simulated images based on Sentinel-2 satellite data, which has similar wavelength specifications to CAS500-4, and examined the possibility of using the products of GEO-KOMPSAT-2A (GK2A) as atmospheric parameters. The sensitivity analysisshowed that AOD wasthe most important parameter with greater sensitivity in visible channels than in the near-infrared region. In particular, since AOD change of 20% causes about a 100% error rate in the blue channel surface reflectance in forests, a highly reliable AOD is needed to obtain accurate surface reflectance. The atmospherically corrected surface reflectance based on the GK2A AOD and WV was compared with the Sentinel-2 L2A reflectance data through the separability index of the known land cover pixels. The result showed that two corrected surface reflectance had similar Seperability index (SI) values, the atmospheric corrected surface reflectance based on the GK2A AOD showed higher SI than the Sentinel-2 L2A reflectance data in short-wavelength channels. Thus, it is judged that the parameters provided by GK2A can be fully utilized for atmospheric correction of the CAS500-4. The research findings will provide a basis for atmospheric correction of the CAS500-4 in the future.

• Korean Journal of Culture and Social Issue
• /
• v.21 no.3
• /
• pp.551-573
• /
• 2015

The rise of single living has been one of the most important demographic shifts of recent decades. The solo household is a little less than 40% in Europe areas and that of Tokyo is over 45%. Being impacted this figure, the formation of single economy is the key word in World Economic Forum(WEF) 2008. Seoul' single household is increasing rapidly. Between 2000 and 2005, the growth of single person is around 34%, the population of single person reached 700,000 people. Now 20% of total household in Seoul is Single household. Living alone or solo living is not exceptional or special in Seoul Metropolitan City. The rise in single living will create pressures towards poverty and inequality and so on. Seoul should develop and prepare the urban policy for single household. We figured out the four key trends which composed of single household in Seoul. Four types of single person are like below : Gold Mr and Miss, Reserved labor forces, depressed single and silver generation. Gold group is amonst people aged 30 and 40 who is working in the area of white collar and professional. They are usually elective single person household who have chosen solo living. Reserved labor forces group is usually among 20s people who have not get the regular hob. For this group, job acquiring is the most important issue. Depressed single person household group is among people aged late 30s and 40s. Its group is the result from the broken family. The silver group is among aged over 65 that is the main issue of the aged society. In this research, we stressed that people living alone can be split into two types - elective single person households who have chosen single living, and forced single person household who have been constrained to this lifestyle by circumstances. Except gold group, the rest of the group is the forced single household who are faced to poverty. The monthly income of single person household is almost under 2 million won. Single person household is usually working in the blue collar job and service area. So, except gold group that is the smallest part of single person household, almost single person is not the target of private market, but the object of public policy.