How effective is intragastric balloon insertion as an obesity treatment in Korea?

Youngdae Kim 대한소화기내시경학회 2023 Clinical Endoscopy Vol.56 No.3

EDITORIAL

Planning of Memorial History Park using Abandoned Gyeongchun Line Site

Youngdae Kim,MyungSun Kim,HwanHee Lee 한국색채학회 2017 AIC 2017 Jeju Vol.2017 No.10

In the past, people made efforts for destroying an existing building and constructing a new one in order to improve spaces in the city center and for making space, using a space regeneration method for city regeneration. In such cases, “color” is used as a method of space regeneration, and it plays an important role considering various aspects in spatial planning, such as theme compliance, visibility, and attention, and it is an effective method that can maximize purpose, with a relatively high economic efficiency. Hwarangdae, a modern simple station located in Gongneung-dong, Nowon-gu, Seoul, is an abandoned station, which currently does not function as a station and is designated and preserved as a historical cultural property. However, the local government, thinking that it is not desirable to keep the abandoned station, is trying to rebuild it as a place for conservation and coexistence at the same time. Considering the history, cultural values, and aesthetics of the scenery of Hwarangdae abandoned station, this study was conducted to plan a memorial park using the abandoned Gyeongchun Line site. The objective was to investigate and analyze the space and color of Hwarangdae abandoned station, which is the target place to establish a space plan, and suggest the regeneration theme of Memorial History Park. The shape was composed of straight lines, curved lines, and oblique lines based on the theme of railroad; in the color aspect, the achromatic group of Gray series gave the appearance of tone on tone, complementing the feeling of calm and a reverent feeling of the historic memorial park; it was harmonized with the natural landscape using the color of yellow forsythia flowers blooming in spring as a highlight color to neutralize static and calm images. We believe that this study will be used as a reference for various projects of urban regeneration and space reconstruction, and the Hwarangdae abandoned station will be rebuilt into a better space for citizens as a recreational park.

Seaweed aquaculture: cultivation technologies, challenges and its ecosystem services

Kim, Jang K.,Yarish, Charles,Hwang, Eun Kyoung,Park, Miseon,Kim, Youngdae The Korean Society of Phycology 2017 ALGAE Vol.32 No.1

Seaweed aquaculture technologies have developed dramatically over the past 70 years mostly in Asia and more recently in Americas and Europe. However, there are still many challenges to overcome with respect to the science and to social acceptability. The challenges include the development of strains with thermo-tolerance, disease resistance, fast growth, high concentration of desired molecules, the reduction of fouling organisms and the development of more robust and cost efficient farm systems that can withstand storm events in offshore environments. It is also important to note that seaweed aquaculture provides ecosystem services, which improve conditions of the coastal waters for the benefit of other living organisms and the environment. The ecosystem services role of seaweed aquaculture and its economic value will also be quantitatively estimated in this review.

Application of metagenome analysis to characterize the molecular diversity and saxitoxin-producing potentials of a cyanobacterial community: a case study in the North Han River, Korea

Kim, Keon Hee,Yoon, Youngdae,Hong, Woon-Young,Kim, JaeBum,Cho, Yung-Chul,Hwang, Soon-Jin The Korean Society for Applied Biological Chemistr 2018 Applied Biological Chemistry (Appl Biol Chem) Vol.61 No.2

A wide variety of cyanobacterial species that inhabit freshwater systems are known to produce diverse toxins and off-flavor compounds during the development of environmentally harmful blooms. However, cyanobacterial community development and toxin production potential have not been well studied. In this study, we examined the taxonomic diversity and saxitoxin production potential of cyanobacteria in the water and sediments of a large river, the North Han River in South Korea, by metagenome analysis using next-generation sequencing (NGS) and molecular biological approaches, respectively. NGS revealed that the entire cyanobacterial community in the study area consisted of 39 genera and 47 species. The most abundant genera were Microcystis, Anabaena, Cyanobium, and Synechococcus, which accounted for more than 90% of the entire community. The saxitoxin production potential of the cyanobacterial community was assessed by detecting the sxtA and sxtG genes related to saxitoxin production. Eleven sxtA and 24 sxtG genes were identified through molecular cloning and sequencing. Phylogenic analysis revealed that three sxtA genes that grouped in one phylogenic branch with Scytonema sp. were distinctly separated from the sxtA genes of Anabaena, Aphanizomenon, Lyngbya, and Cylindrospermopsis. Sixteen of the detected sxtG genes were phylogenically similar to those of Anabaena circinalis (Dolichospermum circinale), Aphanizomenon gracile, and Aphanizomenon flos-aquae. Our study demonstrates the utility of the metagenomics approach for characterizing the natural community structure of cyanobacteria containing diverse and even rare species, and the evaluation of saxitoxin-producing potential in the cyanobacterial community.

Transformation of Surface Brightness Profile Types of Dwarf Galaxies : KMTNet Supernova Program Data

Youngdae Lee,Hong Soo Park,Sang Chul Kim,Dae-Sik Moon,Dong-Jin Kim,Sang-Mok Cha 한국천문학회 2018 天文學會報 Vol.43 No.1

미소 시편을 이용한 가스터빈 블레이드 사용품의 인장 및 미세조직 특성평가

Kim Youngdae,He Yinsheng,Bang Jiye,Jung Jinesung 대한금속·재료학회 2022 대한금속·재료학회지 Vol.60 No.11

A gas turbine (GT) blade is a key hot-pass component for advanced GT engines, and should have stable properties under extreme conditions of 1,350°C and 3,600rpm, etc. The GT blade, after operating with nearly 800 equivalent start-stops (ES) or 24,000 equivalent operation hours (EOH), should be replaced due to degradation of properties and microstructure, particularly, the formation of cracks in the airfoil tip and platform region. To date, the assessment of materials, prototype blade, etc, has been extensively studied in a laboratory simulated environment; however, evaluation of the full-scale blades in a service environment has been rarely reported. Here, the properties and microstructures of an F-class GT first stage blade, with a service history of 800ES were investigated. The results showed decreasing tensile properties at the airfoil part due to its higher temperature exposure. The microstructural characterization results revealed that the finer grain size and dendrite interfaces facilitated the formation of Cr-enriched M₂₃C₆ along grain boundaries, as well as the spherical γ' in the airfoil part, resulting in a decrease in tensile properties. The results obtained here provide precious background for assessing the serviced blade and developing advanced blades.

Discovery of the Kinematic Alignment of Early-type Galaxies in the Virgo Cluster

Kim, Suk,Jeong, Hyunjin,Lee, Jaehyun,Lee, Youngdae,Joo, Seok-Joo,Kim, Hak-Sub,Rey, Soo-Chang American Astronomical Society 2018 ASTROPHYSICAL JOURNAL LETTERS - Vol.860 No.1

골격성 III급 비대칭과 하악의 양측 제2소구치 결손을 동반한 부정교합 환자의 절충치료

김영대(YoungDae Kim),채화성(Hwa Sung Chae) 대한치과교정학회 2023 대한치과교정학회 임상저널 Vol.13 No.3

This case report highlights how functional and aesthetic outcomes can be achieved through a compromise treatment for adult patients with moderate skeletal Class III malocclusion and missing teeth. The report focuses on the treatment of a 38-year-old male patient with a bilateral mandibular second premolar edentulism, partial crossbites, and mandibular midline deviation to the right. The mandibular left third molar was fully erupted. The treatment primarily focused on molar distalization. The mandibular right second premolar space was gained, followed by dental implant placement, while that of the mandibular left was completed without further prosthesis. After 19 months of treatment, functional occlusion was achieved, and the initial non-aesthetic gingival line and periodontal problems caused by mesially angulated first molars were improved. The retention records demonstrated stable dentition over 3.5 years.

Modulation of the Metal(loid) Specificity of Whole-Cell Bioreporters by Genetic Engineering of ZntR Metal-Binding Loops

( Hyojin Kim ),( Geupil Jang ),( Bong-gyu Kim ),( Youngdae Yoon ) 한국미생물 · 생명공학회 2020 Journal of microbiology and biotechnology Vol.30 No.5

Bacterial cell-based biosensors, or whole-cell bioreporters (WCBs), are an alternative tool for the quantification of hazardous materials. Most WCBs share similar working mechanisms. In brief, the recognition of a target by sensing domains induces a biological event, such as changes in protein conformation or gene expression, providing a basis for quantification. WCBs targeting heavy metal(loid)s employ metalloregulators as sensing domains and control the expression of genes in the presence of target metal(loid) ions, but the diversity of targets, specificity, and sensitivity of these WCBs are limited. In this study, we genetically engineered the metal-binding loop (MBL) of ZntR, which controls the znt-operon in Escherichia coli. In the MBL of ZntR, three Cys sites interact with metal ions. Based on the crystal structure of ZntR, MBL sequences were modified by site-directed mutagenesis. As a result, the metal-sensing properties of WCBs differed depending on amino acid sequences and the new selectivity to Cr or Pb was observed. Although there is room for improvement, our results support the use of currently available WCBs as a platform to generate new WCBs to target other environmental pollutants including metal(loid)s.

중학교 학생들이 귀추 전략을 적용하여 지구과학 탐구문제를 해결한 사례 분석

김현주(Kim Hyunju),김영대(Kim Youngdae),김동영(Kim Dongyeong),위수민(Wee Soo-Meen) 학습자중심교과교육학회 2018 학습자중심교과교육연구 Vol.18 No.15

본 연구의 목적은 중학교 1학년 학생들이 지구과학 탐구문제 해결에 사용하는 귀추 전략을 분석하여 지구과학 문제 해결 과정의 특징을 규명하는 것이다. 학생들의 배경지식을 활성화시켜 귀추적 사고를 유발할 수 있는 탐구과제의 유형을 분석하여 귀추적 사고가 학생들의 지적, 창의적 사고 능력에 미치는 영향을 파악하였다. 중학교 1학년 학생 18명을 대상으로 3모둠을 구성하여 2007년 개정 교육과정 과학 교과 서의 지구과학 영역 5문항을 제시하였다. 자료 수집은 2011년 2학기에 진행되었으며, 문제 해결과정이 기록된 텍스트와 학생들의 토론과정을 전사하여 추론과정에 사용된 귀추 전략을 귀추법의 삼단논법 형식에 따라 분석하였다. 사례 분석 결과, 지구과 학적 특성을 반영한 문제 해결방법으로서 귀추적 추론은 지구과학 영역에서 적절한 가설을 세워 적용하고 검증하는 방법으로 유의미하였다. 단답형 문제 해결과정에서 유추 전략이 주로 사용되었으나 서술형 문제에서는 귀추 전략이 사용되었다. 특히, 단서가 여러 개 제시되는 문제에서 다양한 귀추 전략을 이용하여 복합적인 사고과정이 관찰되었다. 따라서 지구과학 영역의 문제 해결 능력을 함양시키는 귀추적 탐구 과제가 다양하게 개발될 필요가 있다. 실생활과 유사하도록 단서가 여러 개 존재하는 서술형 탐구문제에 많은 비중을 두어야 할 것이다. 또한 문제에 알맞은 배경 지식과 자료를 제공할 필요가 있음을 시사한다. The purpose of this study is to provide information on problem solving characteristics of earth science questions to teachers through an analysis of abductive strategies that are being used and how they are actually used in solving earth science inquiry questions. Five questions were selected in the field of earth science in the 2007 revised educational curriculum for the first grade middle school science curriculum. Subjects were divided into 3 groups in which they solved earth science inquiry questions and an analysis was conducted by revealing the discussion process of students and tests which recorded the problem solving process from that process. An analysis was conducted on the types of abductive strategies used in the inference process and organizing according to the syllogistic forms of abductive reasoning for the inference process of students. The results of the study are as follows. First, abductive inference method showed to have significance as a verification method reflecting earth science characteristics solving questions as well as establishing and applying appropriate hypothesis. Second, among the strategies used ‘analogy was the most frequently particularly in short-answer questions. Third, various abductive strategies were used in the problem solving process in descriptive answers and a complex thought process appeared using various abductive strategies in questions with multiple answers. Fourth, various abductive strategies were used in solving questions in cases where clues were appropriately provided and where many clues were provided in each step. When looking at the study results, abductive inquiry tasks in the field of earth science improved students intellectual, creative and cognitive skills making it necessary to develop various abductive inquiry tasks. In addition, teachers need to provide questions and appropriate background knowledge as well as materials to induce a right direction for students inquiry.