무기질 불균형: 골 탈석회화와 연조직 석회화

정대원(Daewon Jeong),임현숙(Hyun-Sook Lim),강영희(Young-Hee Kang) 한국식품영양과학회 2009 한국식품영양과학회지 Vol.38 No.12

여러 단백질과 다양한 무기질(칼슘 등)을 함유한 단단한 기관인 골은 정상적으로 다른 연조직 세포로 무기질을 공급하는 역할을 수행하지만, 비타민 결핍, 노화, 폐경기 및 대사성 질환 등으로 인해서 골다공증이 유발되고 동시에 다양한 연조직(심장, 대동맥, 신장, 허파, 췌장 등)의 석회화가 빈번히 유도된다. 같은 중간엽 줄기세포로부터 유래되는 연조직을 구성하는 세포와 조골세포 사이에서는 상호 횡간의 분화가 될 수 있는 여지가 있어, 연조직 세포는 칼슘 축적으로 골을 형성하는 조골세포와 유사한 세포로 분화될 수 있다. 연조직을 이루는 다양한 연조직 장기의 칼슘 축적으로 인한 석회화는 치명적인 장기손상으로 생명을 위협할 수 있으므로 적극적인 예방과 치료가 중요할 것이다. 골다공증과 연조직 석회화는 상호 밀접한 연계성이 있어 한 가지의 질병이 진행되면 다른 질병이 연속적으로 발병할 우려가 있으므로 초기 질병에 대한 적극적인 치료가 필요하다. 향후 초고속 고령화 사회 진입으로 이의 두 질환의 급격한 증가가 예상되므로, vitamin K와 D를 비롯한 다양한 무기질을 균형적으로 조절할 수 있는 식습관과 다량의 항산화제를 함유한 음식물 섭취로 이의 질환을 예방할 수 있을 것이다. Based on the soft and rigid extents, tissues are mainly divided into two groups in mammals, soft tissues including heart, lung, kidney and brain, and hard tissues including tendon, cartilage, teeth and bone. Among various tissues, bone, a dynamic rigid organ, is continuously remodeled by the opposing functional activity between bone formation by osteoblasts and bone destruction by osteoclasts. Bone protects the soft tissues and provides mineral reservoirs, which can supply the mineral needs of other soft tissues to normally maintain cellular function. While calcification in bone is an important action to fundamentally support the body and protect the soft tissues, calcification in soft tissues, including the heart, aorta, kidney, lung and spleen, results in severe organ damages, eventually causing sudden death. A growing body of evidence indicates that the osteoporotic patient who are aging, post-menopausal, diabetes and chronic kidney disease simultaneously represent a high clinical incidence of soft tissue calcification, illustrating a link between soft tissue calcification and bone decalcification (osteoporosis). This study will review what is currently known about the connection between bone decalcification and soft tissue calcification.

The Role of Ruthenium on Carbon-Supported PtRu Catalysts for Electrocatalytic Glycerol Oxidation under Acidic Conditions

Kim, Youngmin,Kim, Hyun Woo,Lee, Seonhwa,Han, Jisu,Lee, Daewon,Kim, Jeong-Rang,Kim, Tae-Wan,Kim, Chul-Ung,Jeong, Soon-Yong,Chae, Ho-Jeong,Kim, Beom-Sik,Chang, Hyunju,Kim, Won Bae,Choi, Sung Mook,Kim, Wiley Blackwell (John Wiley Sons) 2017 ChemCatChem Vol.9 No.9

Formation Tracking Control Algorithm for Multi-agent Combined with Fast Terminal Sliding Mode Control And Disturbance Observer

Daewon Park,Hansol Jeong,Nguyen Ngoc Phi,Sung Kyung Hong 제어로봇시스템학회 2021 제어로봇시스템학회 국제학술대회 논문집 Vol.2021 No.10

This paper presents a robust formation tracking control algorithm for multi-agent system in a finite time. For faster convergence and less steady state error than the existing formation tracking algorithm, we first propose a fast and robust formation tracking control algorithm by using the fast terminal sliding mode control. Then, a disturbance observer algorithm is added to formation tracking control law to handle external disturbances. The stability of the algorithm is verified by Lyapunov theory. The numerical simulation is proposed to show the effectiveness of proposed method using MATLAB environment.

Measuring Psychological Support for the Unemployed: The Case of Kakao NEET Project

( Jaekwan Jeong ),( Kahui Park ),( Yaewon Hyun ),( Daewon Kim ) 한국인터넷정보학회 2021 KSII Transactions on Internet and Information Syst Vol.15 No.4

This paper attempts to investigate Korean youth Not in Education, Employment and Training (NEET) and how daily activities and community participation may influence their positive emotions and job search desire. First, we conducted a focus group interview with 16 NEETs who participated in the Kakao NEET Company project. The project allowed participants to experience employment by founding a virtual company in which each participant selected a daily activity to perform as part of the company’s operations. Second, the interview responses were categorized and assigned emotional values using the card sorting technique and multi-dimensional analysis (MDS). A total of 11 emotional values were derived through this process. Finally, a social network analysis was conducted in order to measure the density of relations among the emotional values. Results suggest that immersion, confidence, belongingness were the three highest values evaluated by participants. Furthermore, network diagrams imply that the stronger participants perceived social support and belongingness with others, the stronger their responsibility grew, further leading them to establish steady goals. In particular, the high eigenvector score for “desire for job” suggests that emotional values are sequentially connected to the immersion-social support-responsibility-goal-job desire. This sequence suggests that digital services that are developed with the aim to enhance social values such as the Kakao NEET Project may engender motivation and confidence in youth NEETs. The overall results suggest that a systematic approach to policymaking should be considered in order to provide fundamental solutions and expand opportunities for social participation and emotional comfort, as social isolation due to low self-esteem has been reported as one of the reasons for NEETs’ failure in the labor market.

통합 서비스 플랫폼을 위한 사물인터넷(IoT) 서비스 분류 알고리즘 개발

조정훈 ( Jeong-hoon Jo ),이대원 ( Daewon Lee ) 한국정보처리학회 2017 한국정보처리학회 학술대회논문집 Vol.24 No.1

센서 및 초근거리 통신 기술의 발전으로 다양한 사물인터넷 서비스가 등장하였다. 현재 사물인터넷 서비스는 단일화된 서비스만을 제공하고 있지만 서비스들이 융합된 새로운 서비스로 발전되고 있다. 서비스 융합시 발생할 수 있는 프로토콜의 다양성, 모듈의 중복성등의 문제를 해결하기 위하여 통합 서비스 플랫폼의 필요성이 대두되었다. 이에 본 연구에서는 보다 효율적인 통합 서비스 플랫폼을 제공하기 위한 기반 연구로 사물인터넷 서비스 분류 알고리즘을 제안한다. 제안하는 서비스 분류 알고리즘은 서비스 별 세부 동작을 기반으로 구성된다. 그리고 후속 연구로 실제 서비스에 제안한 서비스 분류알고리즘을 적용하여 서비스간 유사도 분석을 통한 서비스 그룹화에 관한 연구를 진행할 예정이다.

폐금속 실시간 분류 시스템 개발

김대원(Daewon Kim),박준현(Junhyun Park),박기환(Kyihwan Park),정성호(Sungho Jeong) 대한기계학회 2018 대한기계학회 춘추학술대회 Vol.2018 No.5

콜 대리업체 서비스에서 O2O 방식이 적용된 대리운전 사업 모델로의 소비자 전환 의도에 관한 연구

김대원(Daewon Kim),정혜승(Hye Seung Jeong) 한국전자거래학회 2016 한국전자거래학회지 Vol.21 No.3

O2O(online to offline)가 온라인 상거래(e-commerce)의 새로운 트렌드가 되면서, 다채로운 분야에서 O2O와 기존 산업 간의 결합이 진행되고 있다. 본 연구에서는 이 중 대리운전 산업과 O2O 방식이 접목된 서비스(앱 대리)에 대한 소비자 수용 의사를 탐색했다. 구체적으로 본 연구에서는 기존의 대리운전 서비스 방식인 콜 대리 서비스(콜 대리)에서 O2O 방식이 접목된 앱 대리로의 소비 전환의도를 발생시키는 기제를 확인하고자 했다. 소비전환 의도에 대한 이론적 논의와 확장된 통합기술 수용이론을 토대로 변인을 도출하고, 설문 문항을 고안했다. 설문 조사는 기존의 콜 대리 서비스 경험을 보유한 500명을 대상으로 실시됐다. 연구 결과, 기존의 대리운전 서비스 체계인 콜 대리에 대한 불만족은 콜 대리에서 앱 대리로의 소비 전환 의도를 높이는 요인으로 확인됐다. 콜 대리에 대한 충성도와 콜 대리에서 앱 대리로의 전환 비용은 콜 대리에 대한 불만족과 콜 대리에서 앱 대리로의 소비 전환 의도 간 관계에서 조절 변인으로서 기능을 하지 못하는 것으로 나타났다. 앱 대리 사용 시 기대되는 효과, 앱 대리 사용 과정의 편의성, 앱 대리 사용 과정에서 확보될 수 있는 도움이나 앱 대리 사용에 대한 사용자 개인의 지식의 정도, 그리고 앱 대리의 소비자 가격의 합리성에 대한 기대가 콜 대리에서 앱 대리로의 소비 전환 의도를 제고하는 요인으로서 유의한 영향을 미치는 것으로 확인됐다. 성별, 연령, 그리고 앱 대리 사용 경험은 전술한 앱 대리 선택에 영향을 미치는 요인과 앱 대리로의 소비전환 의도 간의 관계에서 조절 효과 요인으로서는 유의하지 못한 것으로 파악됐다. Online-to-offline (O2O) commerce is the new trend that merges online commerce with traditional industries in various fields. The primary purpose of this paper is to find out which factors influence customers’ intention to switch from call-based driver-for-hire services to O2O app-based services. This study used variables and factors based on Theory of Switching Intention, and Extended Unified Theory of Acceptance and Use of Technology in order to design research questions. We surveyed 500 users of call-based driver-for-hire services. According to the result of this study, dissatisfaction with the current call-based driver-for-hire services is estimated to be a significant factor that strengthens customers’ intention to switch from the call-based driver-for-hire services to the app-based services. Loyalty to the previous call-based driver-for-hire services was not seen as a crucial motivator that causes customers to switch to the new O2O driver service. Switching cost also did not play a key role in explaining the relationship between dissatisfaction with the current call-based service and the intention to use the new app-based service. Performance expectancy, easiness in use, the level of user’s knowledge or available assistance in relation to the use of app-based services, and expectancy for reasonable price was found to have meaningful impacts on customers’ intention to switch from the call-based driver-for-hire services to the app-based services. Age, gender and user experience on the new service were found incapable of moderating the relationship between aforementioned factors which influence customers’ choice of the app-based driver-for-hire service, and customers’ intent to switch to the app-based service.

Bioinspired Transparent Laminated Composite Film for Flexible Green Optoelectronics

Lee, Daewon,Lim, Young-Woo,Im, Hyeon-Gyun,Jeong, Seonju,Ji, Sangyoon,Kim, Yong Ho,Choi, Gwang-Mun,Park, Jang-Ung,Lee, Jung-Yong,Jin, Jungho,Bae, Byeong-Soo American Chemical Society 2017 ACS APPLIED MATERIALS & INTERFACES Vol.9 No.28

<P>Herein, we report a new version of a bioinspired chitin nanofiber (ChNF) transparent laminated composite film (HCLaminate) made of siloxane hybrid materials (hybrimers) reinforced with ChNFs, which mimics the nanofiber-matrix structure of hierarchical biocomposites. Our HCLaminate is produced via vacuum bag compressing and subsequent UV-curing of the matrix resin-impregnated ChNF transparent paper (ChNF paper). It is worthwhile to note that this new type of ChNF-based transparent substrate film retains the strengths of the original ChNF paper and compensates for ChNF papers drawbacks as a flexible transparent substrate. As a result, compared with high-performance synthetic plastic films, such as poly(ethylene terephthalate), poly(ether sulfone), poly(ethylene naphthalate), and polyimide, our HCLaminate is characterized to exhibit extremely smooth surface topography, outstanding optical clarity, high elastic modulus, high dimensional stability, etc. To prove our HCLaminate as a substrate film, we use it to fabricate flexible perovskite solar cells and a touch-screen panel. As far as we know, this work is the first to demonstrate flexible optoelectronics, such as flexible perovskite solar cells and a touch-screen panel, actually fabricated on a composite film made of ChNF. Given its desirable macroscopic properties, we envision our HCLaminate being utilized as a transparent substrate film for flexible green optoelectronics.</P>

Preparation of a Water-based Al/Fe/Mo Catalyst Using a Microfluidic System

Moon, Hyoseung,Jeong, Seok Jae,Lee, Yun Tack,Sohn, Daewon The Chemical Society of Japan 2010 Chemistry letters Vol.39 No.8

<P>We adapted a microfluidic system using water drops in an oil phase to make an Al/Fe/Mo catalyst with a well-defined shape, with the assistance of UV polymerization on the microfluidic channel.</P>

Osteoclast Precursors Display Dynamic Metabolic Shifts toward Accelerated Glucose Metabolism at an Early Stage of RANKL-Stimulated Osteoclast Differentiation

Kim, Jin-Man,Jeong, Daewon,Kang, Hyun Ki,Jung, Sung Youn,Kang, Sam Sik,Min, Byung-Moo S. Karger AG 2007 CELLULAR PHYSIOLOGY AND BIOCHEMISTRY Vol.20 No.6

<P>Mature osteoclasts have an increased citric acid cycle and mitochondrial respiration to generate high ATP production and ultimately lead to bone resorption. However, changes in metabolic pathways during osteoclast differentiation have not been fully illustrated. We report that glycolysis and oxidative phosphorylation characterized by glucose and oxygen consumption as well as lactate production were increased during receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis from RAW264.7 and bone marrow-derived macrophage cells. Cell proliferation and differentiation varied according to glucose concentrations (0 to 100 mM). Maximal cell growth occurred at 20 mM glucose concentration and differentiation occurred at 5 mM concentration. Despite the similar growth rates exhibited when cultured cells were exposed to either 5 mM or 40 mM glucose, their differentiation was markedly decreased in high glucose concentrations. This finding suggests the possibility that osteoclastogenesis could be regulated by changes in metabolic substrate concentrations. To further address the effect of metabolic shift on osteoclastogenesis, we exposed cultured cells to pyruvate, which is capable of promoting mitochondrial respiration. Treatment of pyruvate synergistically increased osteoclastogenesis through the activation of RANKL-stimulated signals (ERK and JNK). We also found that osteoclastogenesis was retarded by blocking ATP production with either the inhibitors of mitochondrial complexes, such as rotenone and antimycin A, or the inhibitor of ATP synthase, oligomycin. Taken together, these results indicate that glucose metabolism during osteoclast differentiation is accelerated and that a metabolic shift towards mitochondrial respiration allows high ATP production and induces enhanced osteoclast differentiation.</P><P>Copyright © 2007 S. Karger AG, Basel</P>