Triboelectric charge modulation of triboelectric nanogenerators using tribo-materials modified with high dielectric nanopaticles

Jaewook Ha,SeongMin Kim,Jin-Baek Kim 한국고분자학회 2016 한국고분자학회 학술대회 연구논문 초록집 Vol.41 No.2

Clinical Status of Inhaled Nitric Oxide Treatment in Infants with Persistent Pulmonary Hypertension of the Newborn in Korea: Post-Marketing Surveillance Results

Jaewook Ha,Eunhee Lee,박현경,Byung-Min Choi 대한신생아학회 2020 Neonatal medicine Vol.27 No.2

Purpose: Inhaled nitric oxide (iNO) is a potent selective pulmonary vasodilator and an important treatment for newborn infants with hypoxic respiratory failure due to persistent pulmonary hypertension of the newborn (PPHN). The Ministry of Food and Drug Safety of Korea first approved iNO in 2009 for use as a new drug to treat hypoxic respiratory failure with PPHN. A post-marketing surveillance study (PMSS) was conducted to assess the effectiveness and safety of the iNO treatment. We evaluated the clinical status of the iNO treatment currently available in Korea by using the PMSS data. Methods: We retrospectively reviewed the PMSS data from 22 hospitals in Korea from October 2014 to September 2018. Altogether, 97 infants were enrolled and divided into early response (ER), delayed response (DR), no response (NR), and death groups according to their response to the iNO treatment. Results: The ER group included 52 infants (53.6%); DR group, 33 (34.0%); NR group, seven (7.2%); and death group, five (5.2%). The iNO treatment was initiated within 14 days after birth at a concentration of 20 ppm. The median treatment duration was 91.5 hours (69.0 to 134.3) in all the infants. Of the infants, 43 (44.3%) received the treatment for >96 hours. Fifty-one infants (52.6%) needed >20 ppm of iNO, and 10 (10.5%) needed a maximum of 80 ppm of iNO. None of the infants had hypermethemoglobinemia or an alarm report of NO2. Conclusion: Korean neonatologists reported that a large proportion of the infants with PPHN showed improvement in oxygenation after treatment with the approved iNO. These infants received relatively longer durations and higher concentrations of the iNO treatment than the current recommendations, without any side and adverse effect.

Transfer-printable micropatterned fluoropolymer-based triboelectric nanogenerator

Ha, Jaewook,Chung, Jihoon,Kim, SeongMin,Kim, Jong Hun,Shin, Seungmin,Park, Jeong Young,Lee, Sangmin,Kim, Jin-Baek Elsevier 2017 Nano energy Vol.36 No.-

<P><B>Abstract</B></P> <P>Triboelectric nanogenerators (TENG) are increasingly considered as a promising energy harvesting system due to high output performance from various wasted energy sources. Numerous studies addressing the TENG configuration improve the performance of these devices by optimizing the paired triboelectric materials and structural geometry. Here, poly(1<I>H</I>,1<I>H</I>,2<I>H</I>,2<I>H</I>-perfluorodecyl methacrylate) (PFDMA) fluoropolymer is adopted as a novel negative tribo-material for application to a TENG, as it is at the topmost negative position of the triboelectric series and it is possible to tune the surface roughness under mild conditions. The intrinsic properties are examined and systematic measurements are carried out with the goal of applying the material to a TENG. PFDMA is suitable for application to a TENG, because PFDMA-TENG exhibits a high voltage, current, and power density of 68V, 6.68μA, and 150μW, respectively, under a load of 500MΩ. Moreover, a PFDMA film offers two distinctive advantages making it ideal for application to a TENG: transmittance higher than 98% even with a relatively high surface roughness, and transfer printing on diverse substrates. The results indicate that PFDMA is a novel negative tribo-material candidate for the fabrication of a TENG with superior triboelectric performance by controlling the surface charge density and morphology.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The new PFDMA shows strategy of fabricating roughened surface under mild condition.. </LI> <LI> This is the first analysis on effective work function and electrical output of PFDMA. </LI> <LI> The super-hydrophobic surface of PFDMA shows energy harvesting from water drops. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Single Point Insulin Sensitivity Estimator for predicting type 2 diabetes mellitus in obese adolescents

Ha Jaewook,Oh Ye-Rim,Kang Eungu,Nam Hyo-Kyoung,Rhie Young-Jun,Lee Kee-Hyoung 대한소아내분비학회 2022 Annals of Pediatirc Endocrinology & Metabolism Vol.27 No.3

Purpose: The prevalence of adolescents with type 2 diabetes mellitus (T2DM) has rapidly increased in Korea over the past few decades with the increase in the number of obese adolescents. The single point insulin sensitivity estimator (SPISE) was recently introduced as a surrogate marker for insulin sensitivity to predict T2DM in adults. We aimed to determine risk factors for T2DM in obese adolescents, including SPISE. Methods: This retrospective study included 104 adolescents diagnosed with T2DM at Korea University Hospital between January 2010 and December 2020. We compared clinical and biochemical parameters and the SPISE of normoglycemic overweight and obese individuals with those of prediabetic and diabetic adolescents to determine risk factors for T2DM. Receiver operating characteristic analysis was performed with the Youden index to determine the cutoff point of SPISE. Results: Frequency of fatty liver and family history of T2DM were significantly higher and SPISE level was significantly lower in patients with T2DM than in normoglycemic overweight/obese and prediabetic adolescents (P<0.01). A family history of T2DM, fatty liver, and SPISE value below the cutoff point (4.49) were identified as significant risk factors for T2DM in multiple logistic regression analysis after controlling for age, sex, and body mass index standard deviation score (P<0.01). Conclusion: Family history of T2DM, fatty liver, and low SPISE (<4.49) are risk factors that can independently affect the occurrence of T2DM in obese adolescents. Among these risk factors, SPISE is a promising marker for predicting adolescent T2DM; careful monitoring of these individuals is needed to prevent progression to T2DM.

3D Reconstruction Method Based on Binary coded Pattern

JaeWook Ha,Soon Kwon,Jaekyo Jeong,HyunWoo Kim 보안공학연구지원센터(IJSIP) 2013 International Journal of Signal Processing, Image Vol.6 No.6

자동차용 SUP-9 스프링강의 파괴인성치에 미치는 압축잔류응력의 영향

정재욱(Jaewook Jung),박원조(Wonjo Park),허선철(Sunchul HUh),이광영(Kwangyoung Lee),하경준(Kyungjun Ha) 한국자동차공학회 2003 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

Recently, the steel parts used at the aerospace and automobile industries are required to be used light weight parts. Therefor, used material, steel have to be a high stress, which is an indispensable condition in this field. At the consideration of parts design, high hardness of the lightweight parts have an benefit of saving fuel and material. A high stress of metal has a point of difference according to the shape of design, external cyclic load and condition of vibration. A crack generates on the surface of metal or under yield stress by defect of inner metal defect or surface defect and slowly, this crack grow stable growth. Finally, rapidity failure phenomena is happen. Fatigue failure phenomena, which happen in metal, bring on danger in human life and property. therefor, antifatigue failure technology take an important part of current industries Currently, the shot peening is used for removing the defect from the surface of steel and improving the fatigue strength on surface. Therefor, this paper investigated the effect on frcature toughness using shot peening which is improve the resistance of crack growth and crack expansion rate by fatigue that make a compressive residual stress on surface.<br/>

Synthesis and characterization of polymeric foaming agent containing sulfonyl hydrazide moiety

Jeong, Jaewook,Yang, Jieun,Ha, Chang-Sik,Cho, Won-Jei,Chung, Ildoo Springer-Verlag 2012 Polymer bulletin Vol.68 No.5

Tat-Dependent Heterologous Secretion of Recombinant Tyrosinase by <i>Pseudomonas fluorescens</i> Is Aided by a Translationally Fused Caddie Protein

Ryu, Jaewook,Byun, Hyunjong,Park, Joseph P.,Park, Jiyeon,Noh, Kyung Ha,Chung, Joo Hee,Lee, Haeshin,Ahn, Jung Hoon American Society for Microbiology 2019 Applied and environmental microbiology Vol.85 No.20

<P>We observed that the <I>S. antibioticus</I> extracellular tyrosinase secretion level was even higher in its nonnatural translationally conjugated fusion protein form than in the natural complex of two separated polypeptides. The results of this study demonstrate that tyrosinase-expressing <I>P. fluorescens</I> can be a stable source of bacterial tyrosinase through exploiting the secretory machinery of <I>P. fluorescens</I>.</P><P>Tyrosinase is a monooxygenase that catalyzes both the hydroxylation of <I>p</I>-hydroxyphenyl moieties to <I>o</I>-catechols and the oxidation of <I>o</I>-catechols to <I>o</I>-quinones. Apart from its critical functionality in melanogenesis and the synthesis of various neurotransmitters, this enzyme is also used in a variety of biotechnological applications, most notably mediating covalent cross-linking between polymers containing <I>p</I>-hydroxyphenyl groups, forming a hydrogel. Tyrosinases from the genus <I>Streptomyces</I> are usually secreted as a complex with their caddie protein. In this study, we report an increased secretion efficiency observed when the <I>Streptomyces antibioticus</I> tyrosinase gene <I>melC2</I> was introduced into <I>Pseudomonas fluorescens</I> along with its caddie protein gene <I>melC1</I>, which has the DNA sequence for the Tat (twin-arginine translocation) signal.</P><P><B>IMPORTANCE</B> We observed that the <I>S. antibioticus</I> extracellular tyrosinase secretion level was even higher in its nonnatural translationally conjugated fusion protein form than in the natural complex of two separated polypeptides. The results of this study demonstrate that tyrosinase-expressing <I>P. fluorescens</I> can be a stable source of bacterial tyrosinase through exploiting the secretory machinery of <I>P. fluorescens</I>.</P>

보행증진을 위한 도시 지역사회 조직의 네트워크 구조와 운영맥락 탐색: 서울시 일개 자치구 사례

강재욱(Jaewook Kang),김동하(Dong Ha Kim),유승현(Seunghyun Yoo) 한국보건교육건강증진학회 2021 보건교육건강증진학회지 Vol.38 No.2

활동적 생활을 위한 걷기증진 공공사업에 관한 고찰

김동하(Dong Ha Kim),강재욱(Jaewook Kang),유승현(Seunghyun Yoo) 한국농촌의학 지역보건학회 2021 농촌의학·지역보건 Vol.46 No.2

본 연구는 지역사회 걷기와 관련된 공공사업의 현황을 확인하고 정책적 시사점을 모색하기 위해 한국의 법령, 중앙정부부처의 백서, 그리고 우수사례로서 서울시 사업을 고찰하였다. 지역사회 걷기와 관련된 법령에는 물리적 환경 개선을 중심으로 제도적 근거가 마련되어 있고, 관련 법령을 소관하는 중앙정부부처에서만 걷기를 목적으로 한 다수의 사업을 장기적으로 추진하고 있어 지역사회 걷기증진을 위한 포괄적인 법적 토대를 구축해야 한다. 서울시는 지역사회 걷기와 관련된 유관부서의 개입이 다각적으로 이루어지고 있지만, 부서를 아우르고 연계, 조정할 수 있는 거버넌스 체계의 개발과 걷기 친숙한 사회문화적 여건을 조성하기 위한 보다 구체적이고 체계화된 노력이 요구된다. Objectives: This study aimed to describe the current public programs for community walking in Korea and to discuss their challenges. Method: We identified the literature related to community walking including five laws, 22 white papers from government departments and 84 program reports from the Seoul Metropolitan Government. Results: Korean law guarantees legal rights and validity to create safe, convenient and equitable environments for community walking. The government department, which has jurisdiction over legislation relating to community walking, has dominated community walking programs, and the role of public health department has been insufficient. Almost all sectors in the department of Seoul Metropolitan Government were involved in community walking programs. However, inter-sectoral cooperation system for community walking was insufficient. Conclusion: It is necessary to revise the condolences of the National Health Promotion Act to establish the role and perspective of public health in community walking promotion. Institutional efforts should be made to expand the network structure between sectors of community walking programs by establishing an organizational, budget, and performance sharing system for inter-sectoral approach.