• The Korean Journal of Physiology and Pharmacology
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• 제10권2호
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• pp.71-77
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• 2006

The goal of this study was to analyze the effects of genistein, a widely used tyrosine kinase inhibitor, on cloned Shaw-type $K^+$ currents, Kv3.1 which were stably expressed in Chinese hamster ovary (CHO) cells, using the whole-cell configuration of patch-clamp techniques. In whole-cell recordings, genistein at external concentrations from 10 to $100{\mu}M$ accelerated the rate of inactivation of Kv3.1 currents, thereby concentration-dependently reducing the current at the end of depolarizing pulse with an $IC_{50}$ value of $15.71{\pm}0.67{\mu}M$ and a Hill coefficient of $3.28{\pm}0.35$ (n=5). The time constant of activation at a 300 ms depolarizing test pulses from -80 mV to +40 mV was $1.01{\pm}0.04$ ms and $0.90{\pm}0.05$ ms (n=9) under control conditions and in the presence of $20{\mu}M$ genistein, respectively, indicating that the activation kinetics was not significantly modified by genistein. Genistein $(20{\mu}M)$ slowed the deactivation of the tail current elicited upon repolarization to -40 mV, thus inducing a crossover phenomenon. These results suggest that drug unbinding is required before Kv3.1 channels can close. Genistein-induced block was voltage-dependent, increasing in the voltage range $(-20\'mV{\sim}0\'mV)$ for channel opening, suggesting an open channel interaction. Genistein $(20{\mu}M)$ produced use-dependent block of Kv3.1 at a stimulation frequency of 1 Hz. The voltage dependence of steady-state inactivation of Kv3.1 was not changed by $20{\mu}M$ genistein. Our results indicate that genistein blocks directly Kv3.1 currents in concentration-, voltage-, time-dependent manners and the action of genistein on Kv3.1 is independent of tyrosine kinase inhibition.

• 스마트미디어저널
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• 제5권3호
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• pp.17-24
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• 2016

우리나라 농업은 현재 농촌인구감소, 농촌인구의 고령화, 곡물자급률 하락, 기후변화 심화 등의 원인으로 어려움을 겪고 있으며, FTA 수입개방의 확대에 따른 우리나라의 농축산업의 경쟁력 확보가 필요하다. 낙후된 경쟁력 확보를 위해 정부에서는 한국형 스마트 팜 확대를 위해 1세대모델부터 3세대모델까지를 정의하고 있으며, 농업의 스마트화를 통해 농업의 성장한계를 극복하고 6차+${\alpha}$산업으로 발전하기 위한 노력하고 있다. 본 논문에서는 2세대 모델에 대한 IoF(Internet of Farming)-Cloud 기반의 실질적인 서비스들에 대한 정의 및 서비스를 검증하며, IoF-Cloud의 온실 테스트베드를 제시한다.

• 한국산학기술학회논문지
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• 제14권3호
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• pp.1519-1526
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• 2013

본 연구에서는 현장조사를 통해 주물 제조 사업장의 일부 용해공정에 적용되고 있는 캐노피 후드(canopy hood)의 흡인 성능을 검토하였다. 또한, CFD model을 이용하여 유해대기오염물질 포집 능력을 향상시킬 수 있는 방안들을 대한 유동장 및 압력장을 비교 및 평가하였다. Case-2(플랜지 부착+이중 후드)의 경우 포집 성능 측면에서는 개선이 가능하지만 후드 정압이 기존 구조보다 약 70% 이상 증가할 것으로 예측되어 현장 적용성이 좋지 않을 것으로 나타났다. 흡인효율을 개선하기 위해서는 case-3(플랜지 부착+이중 콘 부착)의 형상이 가장 적합할 것으로 판단된다. 이는 개구부 중앙에 이중 콘(cone)이 설치되어 후드 가장자리로 유량을 집중시킬 수 있으며, 또한 후드 중앙으로 상승되는 흄(hume)은 콘의 기울기에 의해 정압 상승의 요인 없이 제어할 수 있기 때문이다.

• 폴리머
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• 제28권3호
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• pp.232-238
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• 2004

약물 전달체로서 메톡시 폴리(에틸렌 글리콜) (MPEG, methoxypolyethylene glycol)과 생분해성 폴리에스테르 계열의 카프로탁톤 ($\varepsilon$-CL, $\varepsilon$-caprolactone)으로 구성된 MPEG-PCL 블록 공중합체를 개환중합을 통해 합성하였다. MPEG-PCL의 결정성과 열적특성은 X선 굴절계와 시사주차열량계를 통하여 분석하였다 모델 단백질로서 알부민 (FITC-BSA, albumin bovine-fluorescein isothiocyanate)과 블록 공중합체를 동결 제분 후, 직접압축 성형방법에 의해 웨이퍼를 제조하였다. 알부민의 방출은 pH 7.4 인산염완충액을 사용하여 37$^{\circ}C$에서 14일 동안 관찰하였다. 알부민의 방출양은 형광분광기를 통하여 FITC의 강도에 의해 결정되었다. 웨이퍼의 형태학적 관찰은 디지털 카메라와 전자주사현미경을 통하여 관찰하였다. 알부민의 방출 속도와 초기 burst는 MPEG-PCL 블록 공중합체의 분절 내에서 폴리(에틸렌 글리롤)의 분자량이 증가할수록 또한 폴리카프로락톤의 분자량이 감소할수록 많은 초기방출과 단축된 방출기간을 보였다.

• Nuclear Engineering and Technology
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• 제50권2호
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• pp.218-222
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• 2018

An oxide-dispersion-strengthened (ODS) layer was formed on Zircaloy-4 tubes by a laser beam scanning process to increase mechanical strength. Laser beam was used to scan the yttrium oxide ($Y_2O_3$)-coated Zircaloy-4 tube to induce the penetration of $Y_2O_3$ particles into Zircaloy-4. Laser surface treatment resulted in the formation of an ODS layer as well as microstructural phase transformation at the surface of the tube. The mechanical strength of Zircaloy-4 increased with the formation of the ODS layer. The ring-tensile strength of Zircaloy-4 increased from 790 to 870 MPa at room temperature, from 500 to 575 MPa at $380^{\circ}C$, and from 385 to 470 MPa at $500^{\circ}C$. Strengthening became more effective as the test temperature increased. It was noted that brittle fracture occurred at room temperature, which was not observed at elevated temperatures. Resistance to dynamic high-temperature bursting improved. The burst temperature increased from 760 to $830^{\circ}C$ at a heating rate of $5^{\circ}C/s$ and internal pressure of 8.3 MPa. The burst opening was also smaller than those in fresh Zircaloy-4 tubes. This method is expected to enhance the safety of Zr fuel cladding tubes owing to the improvement of their mechanical properties.

• 대한두개안면성형외과학회지
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• 제12권1호
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• pp.33-36
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• 2011

Background: In a frontal sinus reconstruction, the literature primarily recommends a surgical approach for definite treatment with the exception of for anterior wall fractures with no dislocation. Many studies have assessed a range of methods for the reduction of frontal sinus fractures. This paper presents a case, in whom the anterior wall of the frontal sinus was reconstructed using an outer table calvarial bone graft in an en bloc manner. Patient and methods: A 36-year-old male visited the emergency room with a heavy injury to the forehead. He was diagnosed with fractures of the anterior and posterior wall of the frontal sinus. The neurosurgeon removed the fractured area and repaired the meninges. Afterwards, cranialization was performed and the opening of the nasofrontal duct was obstructed. After fixing the removed bone to its original location, all fragments of fractured anterior wall were purged out and the anterior wall reconstructed using an en bloc calvarial bone graft. Results: In the post-operative 8 months period, there were no complications, the round contour of the forehead was expressed well and the patient was satisfied with the result. Conclusion: There are many methods for reconstructing the anterior wall of the frontal sinus. On the other hand, in cases of large fracture sites with many fractured bone fragments, en bloc harvesting of the outer table calvarial bone could be a better choice than making use of only plates and screws because this method shows a good results in terms of aesthetics with a low complication rate.

• 한국항만경제학회지
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• 제23권2호
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• pp.1-24
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• 2007

빠른 경제성장과 교역량의 증가에 힘입어 중국은 이제 세계에서 가장 많은 컨테이너 물동량을 처리한 국가가 되었다. 그리고 컨테이너선의 대형화와 신속화 추세에 발맞추어 동북아 주요항만이 직면하는 환경도 상당히 빠르게 변하고 있다. 상해항은 육지로부터 약 30km 떨어진 대양산과 소양산을 개발하여 2005년 말에 제1기 터미널을 그리고 2006년에 제2기 터미널을 개장하였다. 그리고 2012년까지 전체 29선석을 조성하여 1,500만 TEU를 처리할 예정으로 있다. 컨테이너 처리물량에서 부산항을 추월한 상해항은 2,006년도 연간 물동량을 약 2,170만 TEU를 처리하여 세계 제3위의 지위를 확고히 했으며, 향후 세계 제1위의 컨테이너 처리항만으로 부상할 것으로 보인다. 세계 제5위의 컨테이너 처리항만이고, 동북아 중심항만이 되고자 하는 부산항에 양산항의 개장 및 향후 개발 계획에 따른 주변 상황에 능동적으로 대처하기 위한 다양한 대응전략을 제시해 본다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제45권1호
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• pp.15-20
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• 2019

Objectives: The aim of this study was to use four sets of success criteria to evaluate the outcomes of arthrocentesis treatment with hyaluronic acid injection in patients with internal derangement (ID) of the temporomandibular joint (TMJ). Materials and Methods: The study included 40 patients diagnosed with unilateral Wilkes stage III TMJ dysfunction. Clinical parameters, including maximum mouth opening (MMO) and pain during function, were evaluated preoperatively, 6 months, and 1 year after TMJ arthrocentesis. Outcomes were assessed and compared using four sets of success criteria from the following: the American Association of Oral and Maxillofacial Surgeons (AAOMS; MMO ${\geq}35mm$ and visual analogue scale [VAS] score ${\leq}3$), Murakami et al.'s criteria (MMO >38 mm and VAS score <2), Emshoff and Rudisch criteria (MMO ${\geq}35mm$ and >50% pain reduction), and patient self-reports (self-evaluation of treatment as successful or unsuccessful). Results: Significant improvements in MMO and pain reduction during function were observed between the preoperative period and 6 months and 1 year postoperatively (P<0.01). The success rates of treatment determined using AAOMS (52.5%), Emshoff and Rudisch criteria (57.5%), and self-reported patient criteria (40.0%) were similar. Application of the Murakami et al. criteria reported the lowest success rate (12.5%). Conclusion: The AAOMS and Emshoff and Rudisch criteria are consistent with patient expectations and can be used to assess treatment efficacy.

• 한국응급구조학회지
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• 제22권3호
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• pp.35-45
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• 2018

Purpose: The purpose of this study was to compare laryngoscopic views and ease of use and success of intubation, via the percentage of glottic opening (POGO) scale when using the Miller blade and Macintosh blade in paraglossal approach. Methods: Forty intern doctors were randomized for laryngoscopy to be performed in a crossover manner. They performed endotracheal intubation with Miller blade and Macintosh blade in two airway scenarios: normal airway and difficult airway with edema. We observed the rate of successful intubation, time required for visualizing the glottis, time to complete endotracheal intubation, ease of intubation, and the POGO scale. Results: In the normal airway, there was no difference in intubation between the two endoscopes. In the difficult airway, the time for visualizing the glottis (7.80 versus 10.24 sec; p=.006), the time to tube passage (19.38 versus 23.03 sec; p=.038) and the time to complete endotracheal intubation (21.84 versus 28.54 sec; p=.022) with Miller blade was shorter than with Macintosh blade. The POGO scale(%) of the Miller blade was higher than that of the Macintosh blade's (62.25 versus 56.32; p=.030). Conclusion: Compared to the Macintosh blade, Miller blade provided better visualization of the glottis and POGO scale, and faster time to completion of endotracheal intubation.

• 의학교육논단
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• 제21권1호
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• pp.41-50
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• 2019

The aim of this study is to analyze the current status and performance evaluation systems of faculty in Korean medical colleges and professional graduate medical schools (called medical schools). We developed a research tool based on previous studies and distributed it to 40 medical schools from July to October 2017. The response rate was 100%. We calculated the number of faculty members and analyzed the faculty evaluation systems and awareness according to national and private medical schools. As of 2017, the number of medical faculty in Korea was 11,111 (4,973 faculty were employed by their alma mater, which is 44.76% of the total), with non-medical doctor faculty accounting for 754 of the total. The medical schools reflect research achievements as most important for re-appointment and screening to promote faculty, and the area of education is secondary excepting clinical faculty of private medical schools. However, important issues in the faculty evaluation deal with the relevance of research achievement and the need for qualitative assessment. Some medical schools revised or have been revising the faculty evaluation system in areas such as minimum standards of education for promotion and separation of promotion and tenure review. Opening non-tenure track lines for faculty show positive effects such as increasing the number of positions for hire and easing the financial burdens of medical schools. Downfalls include inconsistencies between the responsibilities and actual practices of tenure not being available and the instability of faculty's status. In conclusion, medical schools need to prepare a faculty evaluation system that fits the position of faculty members and attempt to establish a reasonable compensation system.