Effect of Mn and C on Age Hardening of Fe–Mn–Al–C Lightweight Steels

Sung‑Won Park,Jun Young Park,Kyong Mox Cho,Jae Hoon Jang,Seong‑Jun Park,Joonoh Moon,Tae‑Ho Lee,Jong‑Ho Shin 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.3

The effects of Mn and C content on the age hardening of Fe–Mn–Al–C lightweight steels, which have austenitic or duplex(austenite and ferrite) microstructures, were investigated. An increase in Mn content induced a delay of the age hardeningthat is caused by the formation of intra-granular κ-carbides. In order to interpret the effect of Mn content, first-principlescalculations were conducted using the supercells of Fe24Al8C8,Fe24Al8C7,Fe24(Al7Mn)C8, and Fe24(Al7Mn)C7. The calculationsshowed that an increase in Mn content could be the source of the delay of the intra-granular κ-carbide formation bysuppressing C atom’ occupation of the vacancy at the body-centered site of L12. An increase in C content accelerated theformation of intra-granular κ-carbides, which induced the intense age hardening, and coarse inter-granular κ-carbides, whichresulted in significant decrease in impact absorbed energy due to inter-granular fracture.

A Multi-Center Educational Research Regarding Breastfeeding for Pediatrics Residents in Korea

Yong Sung Choi,정성훈,김은선,Eun Sun Kim,Eunhee Lee,Euiseok Jung,So-Yeon Lee,이우령,Hye Sun Yoon,Yong Joo Kim,Ji Kyoung Park,Son Moon Shin,Ellen Ai-Rhan Kim 대한신생아학회 2022 Neonatal medicine Vol.29 No.1

Purpose: Pediatricians have a significant responsibility to educate mothers about the importance of breastfeeding. However, there have been minimal efforts in the courses of resident training in Korea. The purpose of this study is to evaluate the change in knowledge and attitude before and after a 4-week breastfeeding educational intervention among multicenter residents. Methods: Prospective interventional educational research was designed for residents at eight training hospitals in Korea. Institutional reviews were obtained in each hospital. The education curriculum consisted of 14 courses regarding breastfeeding theory and practice. These materials were used to teach pediatric residents for 4 weeks. Knowledge-based tests were administered before the course, and re-tests were administered after the course using different test items of similar levels. Test scores and survey responses were compared before and after the intervention. Results: A total of 73 residents (1st year 20, 2nd year 23, 3rd year 16, and 4th year residents 14) from eight training hospitals completed the intervention. Their average age was 30.3±2.9 years, 17 (23.3%) were male, 22 (30.1%) were married, and eight had more than one child of their own. The mean pre-test score was 61.8±13.4 and the mean post-test score was 78.3±7.5 (P<0.001). The inter-grade difference in the score was significant in the pre-test (P=0.005), but not significant in the post-test (P=0.155). There were more responses of obtaining confidence after the intervention (P<0.001). Conclusion: In our study, pediatric residents showed improvement in their knowledge and confidence level after 4 weeks of the breastfeeding curriculum. This will provide a basis for future policymaking in the training of pediatric residents regarding breastfeedReceived: 6 January 2022 Revised: 15 February 2022 Accepted: 15 February 2022 Correspondence to: Ellen Ai-Rhan Kim, MD Department of Pediatrics, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, Korea Tel: +82-2-3010-3390 Fax: +82-2-3010-6978 E-mail: arkim@amc.seoul.kr A Multi-Center Educational Research Regarding Breastfeeding for Pediatrics Residents in Korea Yong-Sung Choi, MD,PhD1, Sung-Hoon Chung, MD, PhD2, Eun Sun Kim, MD, PhD3, Eun Hee Lee, MD4, Euiseok Jung, MD5, So Yeon Lee, MD, PhD5, Wooryoung Lee, MD6, Hye Sun Yoon, MD, PhD7, Yong Joo Kim, MD, PhD8, Ji Kyoung Park, MD, PhD9, Son Moon Shin, MD, PhD9, and Ellen Ai-Rhan Kim, MD, PhD5 1Department of Pediatrics, Kyung Hee University Hospital, Seoul, Korea 2Department of Pediatrics, Kyung Hee University Hospital at Gangdong, Seoul, Korea 3Department of Pediatrics, Kangwon National University Hospital, Chuncheon, Korea 4Department of Pediatrics, Korea University Anam Hospital, Seoul, Korea 5Department of Pediatrics, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea 6Department of Pediatrics, Soonchunhyang University Seoul Hospital, Seoul, Korea 7Department of Pediatrics, Nowon Eulji Medical Center, Eulji University, Seoul, Korea 8Department of Pediatrics, Hanyang University Seoul Hospital, Seoul, Korea 9Department of Pediatrics, Inje University Busan Paik Hospital, Busan, Korea Neonatal Med 2022 February;29(1):28-35 https://doi.org/10.5385/nm.2022.29.1.28 pISSN 2287-9412 . eISSN 2287-9803 Copyright(c) 2022 By Korean Society of Neonatology This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http:// creativecommons.org/licenses/by-nc/4.0), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Original Article 29 Neonatal Med 2022 February;29(1):28-35 https://doi.org/10.5385/nm.2022.29.1.28 ing in Korea.

근막 결손의 복원과 자궁천골인대 고정을 통한 전자궁적출술 후 질탈출의 성공적 교정

문화숙(Hwa Sook Moon),최진국(Jin Koo Choi),김경서(Kyung Seo Kim),박근식(Kyun Sik Park),황지영(Ji Young Hwang),문성은(Sung Eun Moon),한지원(Ji Won Han),김상국(Sang Gook Kim),김상갑(Sang Gap Kim) 대한산부인과학회 2002 Obstetrics & Gynecology Science Vol.45 No.7

목적 : 본 연구는 전자궁적출술 후 질탈출을 부위-특이적인 결함의 개념에 입각하여 치골경부 근막과 직장질 격막의 연결을 통한 골반내 근막의 복원과 자궁천골인대 고정술을 이용한 질탈출의 성공적인 수술적 교정의 방법과 결과를 보고하고자 한다. 연구 방법 : 1999년부터 2001년 8월까지 자궁적출술 후 질궁탈출 증상으로 문화병원 산부인과를 내원, 탈출된 질의 근막을 재건시킨 다음, 이를 자궁천골인대에 고정시킴으로써 질의 부위-특이적인 교정술을 받은 3명의 환자를 대상으로 하였다. 3명중 1명은 개복술을 하였고 2명은 내시경 수술을 하였다. 결과 : 환자의 연령 분포는 49-67세였으며, 수술시간은 평균 113분 (105-125)이었다. 세 환자 모두 수술 후 질의 상태가 해부학 및 기능적으로 정상이었으며, 9일째 특이사항 없이 퇴원하였다. 수술 후 HRT를 시행한 1명을 포함한 3명 모두 각각 24개월, 12개월, 7개월간의 추적 검사에서도 특이한 합병증이나 재발 없이 좋은 경과를 보였다. 결론 : 골반 근막 결손의 복원과 자궁천골인대 고정술은 전자궁적출술 후 질탈출의 교정에 매우 안전하고 효과적이며, 기능적인 방법으로 사료되며, 자궁천골인대를 질탈출 교정에 이용한 연구는 본 연구가 국내에서 처음이다. Objective : To report the method and efficacy of the site specific-defects repair in the endopelvic fascia and uterosacral ligament suspension for the correction of posthysterectomy vaginal vault prolapse. Methods : This study was performed in 3 patients with posthyterectomy vaginal vault prolapse who underwent the surgery for the reconstruction of endopelvic fascia and the correction of vault prolapsed vagina by using uterosacral ligament suspension at the department of Obstetrics and Gynecology in Moon-Hwa Hospital. Among them, 1 patient was treated by laparotomy, and 2 patients were treated by laparoscope. Results : The age of patients ranged from 49 to 67 years. The mean operation time was 111 minutes (105-120 minutes). The status of postoperative vagina was normal in all 3 patients, who were discharged 9 days after operation without symptoms. No complication or recurrence were found in them despite long-term follow-up for 24 months, 12 months, 7 months, respectively after operation. One patient has been treated with HRT therapy. Conclusion : The reconstruction of the defect of endopelvic fascia and uterosacral ligament fixation may be very safe, effective, and functional in the correction of vaginal vault prolapse. This study reports the treatment of vaginal vault prolapse using uterosacral ligament within Korea for the first time.

바이모달 트램의 위치 인식 방법 및 정밀 정차 구현

서기원(Seo Ki-Won),박주연(Park Ju-Yeon),이상남(Lee Sang-Nam),류희문(Ryu Hee-Moon),변윤섭(Byun Yeun-Sub) 한국철도학회 2009 한국철도학회 학술발표대회논문집 Vol.2009 No.5월

This paper presents a method for precisely localizing and parking of bimodal trams. In order to gain an automatically driving system for bimodal trams, precise up-to-date localization, velocity recognition, distance to next station and precise parking location estimation functions are required. This paper proposes a system consisting of control device, steering device, sensor input equipment, driving system, tachometer, vehicle-side sensors, magnetic markers and magnetic sensors. The tram recognizes the precise location via magnetic markers containing information. Parking position and precise distance calculation is embodied by a tachometer. The vehicle-side sensors are used to assure safe station approaching and parking magnetic markers provide improvement of precision while tram parking. This paper provides a system realizing localization and precise parking and afterwards the automatic drive test results are reported and analyzed.

Purification and Partial Characterization of the Storage Protein-like Protein from the 5th Instar Larval Haemolymph of the Chinese Oak Silkworm, Antheraea pernyi .

Park, Nam Suk,Lee, Sang Mong,Moon, Jae Yu,Seong, Su Il 한국잠사학회 1999 한국잠사곤충학회지 Vol.41 No.2

The storage protein-like protein has been purified from the 5th instar larval haemolymph of the Chinese oak silkworm, Antheraea pernyi, and the preparation was shown to be homogeneous by 7.5% nativePAGE. The molecule was consisted of a single Submit with a molecular weight of 80K, but the number of the subunits was not determined. The protein was defined as glycoprotein by Schiffl's reagent stainting. Rabbit antibody prepared against the purified protein crossreacted with the 5th instar larval haemolymph protein of Antheraea pernyi and Anteraea yamamai, but not with those of Bombyx mori and Bombyx mandarina.

Development and validation of rapid and simultaneous method for determination of 12 hair-growth compounds in adulterated products by UHPLC–MS/MS

Park, Han Na,Lee, Ji Hyun,Park, Sung-Kwan,Baek, Sun Young,Lee, Yong-Moon,Kang, Hoil Elsevier 2018 Forensic science international Vol.284 No.-

<P><B>Abstract</B></P> <P>Synthetic hair-growth compounds have been illegally used in diverse products to enhance the short-term efficacy of these products. In this study, a rapid and simultaneous method for the determination of hair-growth compounds in adulterated products based on ultra high pressure liquid chromatography-tandem mass spectrometry (UHPLC–MS/MS) was developed and validated. The limit of detection (LOD) and limit of quantitation (LOQs) of the method were 0.08–43.6ng/mL and 0.27–145ng/mL for the solid-, liquid-, and cream-type samples, respectively. Good calibration linearity for all compounds was demonstrated with a correlation coefficient (<I>r</I> <SUP>2</SUP>) higher than 0.997. The intra- and inter-assay precisions were within 11%. The corresponding accuracies were 86–117% and 81–113%, respectively. The mean recoveries obtained for the solid-, liquid, and cream-type samples ranged from 87 to 114%, with a relative standard deviation (RSD) within 6%. The RSD of the stability evaluated at 4°C for 48h was less than 6%. The established method was used to screen 76 samples advertised as hair-growth treatments, from online and offline markets, over the course of two years. In 10% of the samples, four compounds, including triaminodil, minoxidil, finasteride, methyltestosterone, and testosterone–propionate were detected. The concentrations were in the range of 0.5–16.4mg/g. This technique provides a reliable platform for technical analysis for continuous monitoring of adulterated products to protect public health.</P> <P><B>Highlights</B></P> <P> <UL> <LI> UHPLC–MS/MS used for hair-growth compounds. </LI> <LI> A validated procedure was developed for 12 hair-growth compounds. </LI> <LI> The 76 samples consisted of dietary supplements, drug, sanitary aids and cosmetics. </LI> <LI> Five compounds were detected as adulterants in hair-growth products. </LI> <LI> About 10% of samples were adulterated and accounted in range of 0.5–16.5mg/g. </LI> </UL> </P>

Clinical study on psoriasis patients for past 5 years (2012-2017) in Pusan national university hospital psoriasis clinic

( Sang-hyeon Won ),( Kihyuk Shin ),( Woo-il Kim ),( Min-young Yang ),( Won-ku Lee ),( Tae-wook Kim ),( Sung-min Park ),( Hyun-joo Lee ),( Gun-wook Kim ),( Hoon-soo Kim ),( Hyun-chang Ko ),( Moon-bum K 대한피부과학회 2018 대한피부과학회 학술발표대회집 Vol.70 No.2

Background: Psoriasis is an chronic inflammatory disease affecting multiple aspects of patients’ lives. The long-term clinical study with large number of patients is important to elucidate the epidemiologic and clinical features of psoriasis. Objectives: To investigate the epidemiologic and clinical characteristics of psoriasis patients from the Psoriasis Clinic of Pusan National University Hospital. Methods: Clinical data were collected and analyzed from the medical records of 541 psoriasis patients, who were newly diagnosed as psoriasis at the Psoriasis Clinic of Pusan National University Hospital between 2012 and 2017. Results: The sex ratio was 1.5:1 (male 60.6%, female 39.4%). The peak age of onset was 20s. The most common morphological type was small plaque (63.6%), followed by large plaque (27.2%) and guttate (6.8%). Nail involvement and psoriatic arthritis accompanied in 20.3% and 9.6% of patients, respectively. Hypertension (14.2%), diabetes mellitus (7.2%), and dyslipidemia (5.2%) were the most frequently observed comorbidities in patients with psoriasis. The most common oral agents as initial treatment was Methotrexate (76.8%), followed by Cyclosporin (19.9%) and Acitretin (3.3%). Conclusion: This study highlighted the epidemiologic and clinical characteristics of psoriasis in Korea.

Biodegradation of Gas-phase Styrene in a High-performance Biotrickling Filter using Porous Polyurethane Foam as a Packing Medium

Moon, Cheul-Hyun,Lee, Eun-Yeol,Park, Sung-Hoon 한국생물공학회 2010 Biotechnology and Bioprocess Engineering Vol.15 No.3

A biotrickling filter (BTF) packed with porous polyurethane (PU) foam sheets was developed and operated for removal of gas-phase styrene. The specific surface area and void fraction of the PU foam sheet were determined to be 497 $m^2/m^3$ and 0.92, respectively, by using mathematical modeling and experimental measurement. The effects of gas flow direction (co-current and counter-current), styrene loading rate and empty bed residence time on the efficiency of the BTF were analyzed. The BTF achieved a high elimination capacity of 4.0 ~ 5.0 kg styrene/$m^3$day due to the high specific surface area of the PU foam. The BTF could be operated repeatedly when excessively-grown biomass was periodically removed, using circulating NaOH solution for 2 h every four days.

A Study on Robust Control of Robotic Hand with 12 Joints

Moon-Youl Park,Byoung-Kyun Shim,Ki-Won Sung,Sung-Won Jung,Yang-Keun Jeong,Eon-Uck Kang,Sung-Hyun Han 제어로봇시스템학회 2013 제어로봇시스템학회 국제학술대회 논문집 Vol.2013 No.10

Graphene quantum dots: structural integrity and oxygen functional groups for high sulfur/sulfide utilization in lithium sulfur batteries

Park, Jungjin,Moon, Joonhee,Kim, Chunjoong,Kang, Jin Hyoun,Lim, Eunhak,Park, Jaesung,Lee, Kyung Jae,Yu, Seung-Ho,Seo, Jung-Hye,Lee, Jouhahn,Heo, Jiyoung,Tanaka, Nobuo,Cho, Sung-Pyo,Pyun, Jeffrey,Caban Nature Publishing Group 2016 NPG Asia Materials Vol.8 No.-

<P>Lithium-sulfur (Li-S) batteries are expected to overcome the limit of current energy storage devices by delivering high specific energy with low material cost. However, the potential of Li-S batteries has not yet been realized because of several technical barriers. Poor electrochemical performance is mainly attributed to the low electrical conductivity of the fully charged and discharged species, the irreversible loss of polysulfide anions and the decrease in the number of electrochemically active reaction sites during battery operation. Here, we report that the introduction of graphene quantum dots (GQDs) into the sulfur cathode dramatically enhanced sulfur/sulfide utilization, yielding high performance. In addition, the GQDs induced structural integrity of the sulfur-carbon electrode composite by oxygen-rich functional groups. This hierarchical architecture enabled fast charge transfer while minimizing the loss of lithium polysulfides, which is attributed to the physicochemical properties of GQDs. The mechanisms through which excellent cycling and rate performance are achieved were thoroughly studied by analyzing capacity versus voltage profiles. Furthermore, experimental observations and theoretical calculations further clarified the role played by GQDs by proving that C-S bonding occurs. Thus, the introduction of GQDs into Li-S batteries will provide an important breakthrough allowing their use as high-performance and low-cost batteries for next-generation energy storage systems.</P>