광화학적 방법을 통한 InP계 양자점 표면결함 부동태화 연구

김도연,박현수,조혜미,김범성,김우병,Kim, Doyeon,Park, Hyun-Su,Cho, Hye Mi,Kim, Bum-Sung,Kim, Woo-Byoung 한국분말야금학회 2017 한국분말재료학회지 (KPMI) Vol.24 No.6

In this study, the surface passivation process for InP-based quantum dots (QDs) is investigated. Surface coating is performed with poly(methylmethacrylate) (PMMA) and thioglycolic acid. The quantum yield (QY) of a PMMA-coated sample slightly increases by approximately 1.3% relative to that of the as-synthesized InP/ZnS QDs. The QYs of the uncoated and PMMA-coated samples drastically decrease after 16 days because of the high defect state density of the InP-based QDs. PMMA does not have a significant effect on the defect passivation. Thioglycolic acid is investigated in this study for the effective surface passivation of InP-based QDs. Surface passivation with thioglycolic acid is more effective than that with the PMMA coating, and the QY increases from 1.7% to 11.3%. ZnS formed on the surface of the InP QDs and S in thioglycolic acid show strong bonding property. Additionally, the QY is further increased up to 21.0% by the photochemical reaction. Electron-hole pairs are formed by light irradiation and lead to strong bonding between the inorganic and thioglycolic acid sulfur. The surface of the InP core QDs, which does not emit light, is passivated by the irradiated light and emits green light after the photochemical reaction.

Overcoming anticancer resistance by photodynamic therapy-related efflux pump deactivation and ultrasound-mediated improved drug delivery efficiency

김도연,Park Suhyun,Yoo Hongkeun,Park Suhyeon,Kim Jeewon,Yum Kyuhee,김광명,Kim Hyuncheol 나노기술연구협의회 2020 Nano Convergence Vol.7 No.30

One of the major obstacles to successful chemotherapy is multi-drug resistance (MDR). A multi-drug resistant cancerous cell abnormally overexpresses membrane transporters that pump anticancer drugs out of the cell, resulting in low anticancer drug delivery efficiency. To overcome the limitation, many attempts have been performed to inhibit the abilities of efflux receptors chemically or genetically or to increase the delivery efficiency of anticancer drugs. However, the results have not yet been satisfactory. In this study, we developed nanoparticle-microbubble complexes (DOX-NPs/Ce6-MBs) by conjugating doxorubicin loaded human serum albumin nanoparticles (DOX-NPs) onto the surface of Chlorin e6 encapsulated microbubbles (Ce6-MBs) in order to maximize anticancer efficiency by overcoming MDR. Under the ultrasound irradiation, DOX-NPs and Ce6 encapsulating self-assembled liposomes or micelles were effectively delivered into the cells due to the sonoporation effect caused by the microbubble cavitation. At the same time, reactive oxygen (ROS) generated from intracellularly delivered Ce6 by laser irradiation arrested the activity of ABCG2 efflux receptor overexpressed in doxorubicin-resistant breast cancer cells (MCF-7/ADR), resulting in increased the chemotherapy efficacy. In addition, the total number of side population cells that exhibit the properties of cancer stem-like cells were also reduced by the combination of photodynamic therapy and chemotherapy. In conclusion, DOX-NPs/Ce6-MBs will provide a platform for simultaneously overcoming MDR and increasing drug delivery and therefore, treatment efficiency, under ultrasound irradiation.

Effects of endurance and strength training of cyclists and triathlon athletes on efficiency, economy and VO₂ kinetics

김도연,Kim, Do-Yeon The Society of Digital Policy and Management 2013 디지털융복합연구 Vol.11 No.11

The purpose of this study was to evaluate the economy and efficiency of two trained athlete groups of different training status. The subjects were 20 elite athletes composed of the cyclists group (n=10) and triathlon group (n=10). All subjects performed steady state testing at 50, 100, and 150 watts, with ample time to reach resting $VO_2$ and ventilation values between stages. The efficiency of two groups appears to be quite different, with triathlon competitors displaying superior efficiency values for the transitions from 0 to 50 and 100 watts. This same principle likely explains the economy of the groups, as triathlon competitor was again more economic at 50 and 100 watts. As though this matching of oxygen consumption and workload they can reduce the amount of oxygen deficit that must be repaid post exercise.

개방과 혁신을 통한 미래설계

김도연,Kim, Do-Yeon 한국특허정보원 2010 Patent 21 Vol.- No.92

연부 조직에 발생한 사구종

김도연,이수현,김민주,신규호,Kim, Do-Yeon,Lee, Soo-Hyun,Kim, Min-Ju,Shin, Kyoo-Ho 대한근골격종양학회 2009 대한골관절종양학회지 Vol.15 No.1

Purpose: Glomus tumors are rare benign vascular tumors, usually located in the skin or soft tissue of extremities. Approximately 30-50% of glomus tumors occur in subungal area, but glomus tumors have been described in every location even where glomus bodies are not or rarely present. The purpose of this study was to identify clinical, histologic and MRI characteristics of soft tissue glomus tumor. Materials and Methods: Between 1993 and 2008, eight patients underwent surgery of soft tissue Glomus tumor at our institution. Exclusion criteria were patients with Glomus tumors in digits, stomach, trachea and glomus tympanicum. We analyzed medical records, interviews, physical examinations, MR findings and histolocial types retrospectively. Results: There were four men and four women. The mean age was fourty-seven years. The mean prevalence time was eight-point-nine years. In the classic triad of symptoms, all eight patients had pain and tenderness. Two patients complained of cold sensitivity. Two showed skin color changes. After surgery, two showed symptom improvement (VAS $9^{\circ}{\rightarrow}8$, $8^{\circ}{\rightarrow}5$) and?six showed complete disappearance of symptoms. Slightly symptom improvemented (VAS $9^{\circ}{\rightarrow}8$) one had additional surgery two times after first surgery due to relapse/remaining Glomus tumor. The mean size was 13.9 mm. In histology, six were 'solid glomus tumor', one was a mixture of 'solid glomus tumor' and 'lomangioma' and one was 'malignant glomus tumor'. MR findings showed isointense signal on T1 image, high signal on T2 image and strong enhancement on the Gadolinium enhanced image. Conclusion: Glomus tumor has low recurrence rate and malignant change, rapid diagnosis and surgical excision is critical in treatment to prevent unnecessary pain of patient.

산업제어시스템의 사이버보안을 위한 취약점 분석

김도연,Kim, Do-Yeon 한국전자통신학회 2014 한국전자통신학회 논문지 Vol.9 No.1

Industrial control system (ICS) is a computer based system which are typically used in nation-wide critical infra-structure facilities such as electrical, gas, water, wastewater, oil and transportation. In addition, ICS is essentially used in industrial application domain to effectively monitor and control the remotely scattered systems. The highly developed information technology (IT) and related network techniques are continually adapted into domains of industrial control system. However, industrial control system is confronted significant side-effects, which ICS is exposed to prevalent cyber threats typically found in IT environments. Therefore, cyber security vulnerabilities and possibilities of cyber incidents are dramatically increased in industrial control system. The vulnerabilities that may be found in typical ICS are grouped into Policy and Procedure, Platform, and Network categories to assist in determining optimal mitigation strategies. The order of these vulnerabilities does not necessarily reflect any priority in terms of likelihood of occurrence or severity of impact. Firstly, corporate security policy can reduce vulnerabilities by mandating conduct such as password usage and maintenance or requirements for connecting modems to ICS. Secondly, platfom vulnerabilities can be mitigated through various security controls, such as OS and application patching, physical access control, and security software. Thirdly, network vulnerabilities can be eliminated or mitigated through various security controls, such as defense-in-depth network design, encrypting network communication, restricting network traffic flows, and providing physical access control for network components.

유럽의 포장 폐기물 발생 및 포장 재료별 재활용에 관한 고찰

김도연,고의석,이학래,심원철,양력명,김재능,Kim, Doyeon,Ko, Euisuk,Lee, Hakrae,Shim, Woncheol,Yang, Liming,Kim, Jaineung 한국포장학회 2017 한국포장학회지 Vol.23 No.1

In order to confirm European packaging waste statistics, this study was investigated annual variability of packaging waste generated, target of recovery and recycling rate for packaging waste and recycling rate of European countries based on Eurostat database. Eurostat is regional society statistics organization designated by European community to distribute development, production and European statistics. From 2005 to 2013, paper and paperboard packaging were generated the largest amount among the total amount of packaging waste generated during the period and the share of main packaging materials were generally constant among the packaging materials. In addition, European Union member countries have established target for the recycling rate and recycling rate for packaging waste which has been well maintained by most EU countries since the 2008 directive was enacted. The recycling rate for whole packaging waste such as glass, paper and paperboard, metal, plastic, wood continues to increase in Europe. In this study, Europe packaging waste statistics were organized and analyzed as yearly transformation of Europe packaging waste occurrence and disposal, recycling rate and recovery rate target value of Europe countries and recycling rate of each country in Europe base on centralized Eurostat database. Moreover GDP reduction were also confirmed due to trend changes and indirect impacts such as economic slump by packaging waste and recycling.

위성방송사업자 선정경과 및 사업전망

김도연,Kim, Do-Yeon 한국위성정보통신학회 2001 위성통신과 우주산업 Vol.9 No.1

급성 아킬레스건 파열의 수술적 치료: 경피적 봉합술과 관혈적 봉합술의 비교

김도연,김상범,허윤무,이정범,임재우,오형탁,Kim, Do-Yeon,Kim, Sang-Bum,Heo, Youn-Moo,Lee, Jung-Bum,Lim, Jae-Woo,Oh, Hyeong-Tak 대한족부족관절학회 2011 대한족부족관절학회지 Vol.15 No.2

Purpose: The purpose of the present study was to compare and analyze the clinical outcomes of the percutaneous and open repair of acute Achilles tendon ruptures. Materials and Methods: We performed a retrospective study on 24 patients (group 1) managed with percutaneous repair, and 21 patients (group 2) managed with open repair for acute Achilles tendon rupture. The postoperative evaluations were done by an Arner-Lindholm scale and AOFAS score. Postoperative overall satisfaction and cosmetic satisfaction were also evaluated. Results: By Arner-Lindholm scale and AOFAS score, there was no difference between two groups (p<0.05). As for postoperative overall satisfaction, 5 cases were very satisfied, 16 cases were satisfied and 3 cases were fair in group 1. In group 2, 12 cases were very satisfied, 9 cases were satisfied. For postoperative cosmetic satisfaction, 13 cases were satisfied, 11 cases were fair in group 1. In group 2, 9 cases were very satisfied, 12 cases satisfied. In open repair group, a case of deep wound infection and three cases of skin necrosis were reported as complication. 2 cases of sural nerve injury were seen in percutaneous repair group and were recovered within 3 months. Conclusion: Percutaneous repair of acute Achilles tendon ruptures have high level of cosmetic satisfaction compared with open repair without any significant difference in clinical outcomes.

말기 암 환자에서 완화적 진정 증례 토론

김도연,Kim, Do-Yeun 한국호스피스완화의료학회 2008 한국호스피스.완화의료학회지 Vol.11 No.2

Palliative sedation has been used in patients who undergo intractable suffering at the end of life. Its implementation, however, may be complicated due to resistance of clinicians and barrier of bioethical issues. Here, we present 50-year-old man with stomach cancer and multiple bone metastasis who was treated with palliative chemotherapy and radiotherapy. He suffered from refractory pain on the whole body even after standard analgesics and multidisplinary effort to relieve. Upon shared decision for sedation, he was given midazolam until discharge. Literature reviews reveal cases similar to the present case.