• Journal of Chest Surgery
• /
• v.46 no.5
• /
• pp.346-352
• /
• 2013

Background: Transcatheter aortic valve implantation (TAVI) has been an alternative to conventional aortic valve replacement (AVR) in old and high risk patients. The goal of this study is to compare the early outcomes of conventional AVR vs. TAVI in high risk severe AS patients. Methods: From January 2008 to July 2012, 44 high risk severe aortic stenosis patients underwent conventional AVR, and 15 patients underwent TAVI. We compared echocardiographic data, periprocedural complication, and survival. The mean follow-up duration was $14.5{\pm}10$ months (AVR), and $6.8{\pm}3.5$ months (TAVI), respectively. Results: AVR group was younger ($78.2{\pm}2.4$ years vs. $82.2{\pm}3.0$ years, p<0.001) and had lower operative risk (Euroscore: $9.4{\pm}2.7$ vs. $11.0{\pm}2.0$, p=0.044) than TAVI group. There was no significant difference in early mortality (11.4% vs. 13.3%, p=0.839), and 1 year survival ($87.4%{\pm}5.3%$ vs. $83.1%{\pm}1.1%$, p=0.805). There was no significant difference in postoperative functional class. There was no significant difference in periprocedural complication except vascular complication (0% [AVR] vs. 13.3% [TAVI], p=0.014). TAVI group had more moderate and severe paravalvular leakage. Conclusion: In this study, both groups had similar periprocedural morbidity, and mortality. However, TAVI group had more greater than moderate paravalvular leakage, which can influence long-term outcome. Since more patients are treated with TAVI even in moderate risk, careful selection of the patients and appropriate guideline need to be established.

• Journal of Chest Surgery
• /
• v.46 no.4
• /
• pp.249-255
• /
• 2013

Background: The continuous suture (CS) technique has several advantages as a method for simple, fast, and secure aortic valve replacement (AVR). We used a simple CS technique without the use of a pledget for AVR and evaluated the surgical outcomes. Materials and Methods: Between October 2007 and 2012, 123 patients with aortic valve disease underwent AVR alone (n=28) or with other concomitant cardiac procedures (n=95), such as mitral, tricuspid, or aortic surgery. The patients were divided into two groups: the interrupted suture (IS) group (n=47), in which the conventional IS technique was used, and the CS group (n=76), in which the simple CS technique was used. Results: There were two hospital deaths (1.6%), which were not related to the suture technique. There were no significant differences in cardiopulmonary bypass time or aortic cross-clamp time between the two groups for AVR alone or AVR with concomitant cardiac procedures. In the IS group, two patients had prosthetic endocarditis and one patient experienced significant perivalvular leak. These patients underwent reoperations. In the CS group, there were no complications related to the surgery. Postoperatively, the two groups had similar aortic valve gradients. Conclusion: The simple CS method is useful and secure for AVR in patients with aortic valve disease, and it may minimize surgical complications, as neither pledgets nor braided sutures are used.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.25 no.1
• /
• pp.96-101
• /
• 2021

Arduino is one of the open source microcontroller projects, and Arduino boards using AVR microcontrollers are commonly used. In general, AVR microcontrollers use ISP (In System Programming) upload, but in Arduino, serial upload through a bootloader is basically used, and a dedicated microcontroller is built into the board for this purpose. In order to use the ISP upload in Arduino, a dedicated upload device is required, which is not included in the Arduino board. In this paper, we propose a unified programmer that can handle ISP upload and serial upload through one dedicated microcontroller, and show that ISP and serial upload are possible using the unified programmer. In addition, the proposed unified programmer works as a USB-serial converter, supports serial communication with a computer, and it is also possible to burn the Arduino bootloader. All operations of the unified programmer can be confirmed through the experimental results.

• Molecules and Cells
• /
• v.39 no.5
• /
• pp.426-438
• /
• 2016

Plant disease resistance occurs as a hypersensitive response (HR) at the site of attempted pathogen invasion. This specific event is initiated in response to recognition of pathogen-associated molecular pattern (PAMP) and subsequent PAMP-triggered immunity (PTI) and effector-triggered immunity (ETI). Both PTI and ETI mechanisms are tightly connected with reactive oxygen species (ROS) production and disease resistance that involves distinct biphasic ROS production as one of its pivotal plant immune responses. This unique oxidative burst is strongly dependent on the resistant cultivars because a monophasic ROS burst is a hallmark of the susceptible cultivars. However, the cause of the differential ROS burst remains unknown. In the study here, we revealed the plausible underlying mechanism of the differential ROS burst through functional understanding of the Magnaporthe oryzae (M. oryzae) AVR effector, AVR-Pii. We performed yeast two-hybrid (Y2H) screening using AVR-Pii as bait and isolated rice NADP-malic enzyme2 (Os-NADP-ME2) as the rice target protein. To our surprise, deletion of the rice Os-NADP-ME2 gene in a resistant rice cultivar disrupted innate immunity against the rice blast fungus. Malic enzyme activity and inhibition studies demonstrated that AVR-Pii proteins specifically inhibit in vitro NADP-ME activity. Overall, we demonstrate that rice blast fungus, M. oryzae attenuates the host ROS burst via AVR-Pii-mediated inhibition of Os-NADP-ME2, which is indispensable in ROS metabolism for the innate immunity of rice. This characterization of the regulation of the host oxidative burst will help to elucidate how the products of AVR genes function associated with virulence of the pathogen.

• Proceedings of the Korean Institute of Communication Sciences Conference
• /
• 2006.07a
• /
• pp.352-352
• /
• 2006

• Journal of Chest Surgery
• /
• v.50 no.4
• /
• pp.255-262
• /
• 2017

Background: Transcatheter aortic valve replacement (TAVR) has been suggested as a less invasive treatment for high-risk patients with aortic valve disease. I n this study, we compared the outcomes of conventional surgical aortic valve replacement (AVR) and TAVR in elderly patients aged over 80. Methods: A total of 108 patients aged 80 years or older who underwent isolated AVR (n=35) or TAVR (n=73) from 2010 through 2015 at Asan Medical Center were identified. Early and late clinical outcomes, including echocardiographic findings, were evaluated in both groups. The mean follow-up duration was $766.4{\pm}528.7days$ in the AVR group and $755.2{\pm}546.6days$ in the TAVR group, and the average timing of the last follow-up echocardiography was at $492.6{\pm}512.5days$ in the AVR group and $515.7{\pm}526.8days$ in the TAVR group. Results: The overall early mortality was 2.8% (0 of 35, 0% in the AVR group vs. 3 of 73, 4.1% in the TAVR group). Permanent pacemaker insertion was significantly more common in the TAVR group (p=0.010). Renal failure requiring dialysis and new-onset atrial fibrillation was more frequent and the length of hospital stay was longer in the AVR group; however, this difference did not reach statistical significance. In the TAVR group, 14 patients (19.2%) were rehospitalized due to cardiac problems, and 13 patients (17.8%) had developed significant paravalvular leakage by the time of the last follow-up echocardiography. Conclusion: TAVR could be a good alternative to conventional surgical AVR in elderly patients. However, TAVR has several shortcomings, such as frequent significant paravalvular leakage or readmission, which should be considered in decision-making.

• Journal of Intelligence and Information Systems
• /
• v.15 no.3
• /
• pp.17-29
• /
• 2009

C programming is a main programming for the Educational Robot Arm which is based on AVR ATmega128. The development environment is not integrated, so it is complex and difficult to study for middle or high school students who want to learn programming and control the educational robot arm. Furthermore, there is no debug and testing environment support. This paper presents a Java-based development platform for the educational robot arm. This platform includes: an up-to-date tiny Java Virtual Machine (NanoVM) for the educational robot arm; An Eclipse based Java integrated development environment as an Eclipse plug-in; a 3D simulator on the PCs to support testing and debugging programs without real robots. The Java programming environment makes development for educational robot arm easier for students.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.51 no.2
• /
• pp.214-219
• /
• 2014

In this paper, a new robot system is designed and manufactured to improve the educational robot. The main processor is realized using the ARM Cortex-M3 and the co-processor is implemented by AVR ATMega2560 to deal with data coming from sensor modules. The processor of sensor modules was developed by the AVR ATMega8. The communication system is composed with IIC communication to alleviate the load of main processor. We have developed the educational robot system adopting the hub module for extension characteristics.

• Proceedings of the KIPE Conference
• /
• 2005.07a
• /
• pp.317-320
• /
• 2005

본 논문은 멀티-레벨 H-bridge 인버터에서 입력전압 변동에 따른 AVR(Auto Voltage Regulation)기능을 적용 그 타당성을 제안하였다. 기존의 범용 인버터에서 (V/F)로 구동되는 전동기 시스템에 있어서 인버터에 공급되는 입력 전압은 출력 주파수에 따라 출력 전압 비율을 일정하게 하고 기동에 필요한 전압을 더하여 출력하는 방식이다. 집중 제어 방식의 멀티-레벨 H-bridge 인버터에서는 Cell의 DC-Link 전압을 Master에서 받아들여서 각각의 Cell에 기준 전압값을 지령하게 된다. 그러므로 입력 전압 변동에 따른 DC-Link 전압의 변동이 발생하게 되면 상전압 Unbalance 가 발생하게 되어 부하가 원하는 출력 전압을 낼 수가 없게 된다. 또한 각각의 Cell을 제어하는 Master 제어기가 가지고 있는 문제점을 보완하여 각각의 Cell 제어기 스스로가 AVR을 수행하는 좀더 나은 방법을 제안하였다.

• Journal of the Korean Wood Science and Technology
• /
• v.41 no.5
• /
• pp.456-465
• /
• 2013

Log cross sections of yellow poplar were dried in a radio frequency vacuum (RFV) dryer under alternating vacuum and release (AVR) process. The average moisture content (MC), temperature and vapor pressure at the volumetric center were monitored as functions of time. Three different log thicknesses (33, 60 and 75mm) were tested. The results show that the AVR process caused an increase in the drying rate when the moisture content was above fiber saturation point (FSP, about 30% MC) but that it had an inverse effect on the drying rate when the MC was below FSP. The effect of the AVR process on the drying rate decreased, and the severity of heart checks increased, with the increase in the thickness of the specimens.