Comparative occurrence of ischemic stroke with the rhythm versus rate control strategy in a national prospective cohort of atrial fibrillation

( Jae Guk Kim ),( Young Soo Lee ),( Ki-woon Kang ),( Eue-keun Choi ),( Myung-jin Cha ),( Jung-myung Lee ),( Jin-bae Kim ),( Junbeom Park ),( Jin-kyu Park ),( Tae-hoon Kim ),( Jae-sun Uhm ),( Jaemin Sh 대한내과학회 2021 The Korean Journal of Internal Medicine Vol.36 No.1

Background/Aims: Comparative occurrence of ischemic stroke for rhythm versus rate control strategy in patients with non-valvular atrial fibrillation (NVAF) is still inconclusive. The purpose of this study was to investigate whether the rhythm control strategy is associated with a lower risk of ischemic stroke compared to the rate control strategy in NVAF patients. Methods: The CODE-AF registry prospectively enrolled 6,280 consecutive patients who were treated for NVAF at 10 tertiary referral centers in South Korea. Of these, 2,513 NVAF patients (age, 67 ± 10 years; male, 61.8%) were clinically followed up for over 1-year and divided into rate and rhythm control groups. Results: Those treated with the rhythm control strategy were younger and had less proportions of underlying disease compared to those treated with the rate control strategy. After the propensity matching analysis, those treated with the rhythm control strategy had similar baseline characteristics including the CHA₂DS₂-VASC score compared to those treated with the rate control strategy. The rate of oral anticoagulation, all bleeding, and hospitalization were also similarly between the two groups. The incidence rate of ischemic stroke in the rhythm control group was significantly lower than in the rate control group (0.7 vs. 6.9 per 1,000 person-years, p = 0.011). Conclusions: The rhythm control strategy demonstrated a beneficial effect to lower the risk of ischemic stroke during a 1-year follow-up compared to the rate control strategy.

[논문]전위차계를 이용한 유리 소결체의 소결도 측정

차재민,이병철,류봉기 釜山大學校生産技術硏究所 2003 生産技術硏究所論文集 Vol.62 No.-

PDP(Plasrna Display Panel) Rib은 PDP의 부품 중 매 우 중요한 부분의 하나이 며 Rib의 소결 정도는 cross-talk와 같은 현상을 방지하는 데에 중요한 역할을 한다. Rib은 주로 스크린 프린팅법에 의해 제작되지만, 인쇄, 소성 등 일련의 제조 공정을 거친 후 얻어진 수백 μm 미세규격의 격벽 소결체의 소결도를 정확히 평가하기는 쉽지 않다. 본 연구에서는 Rib의 소결도를 직접적 판단할 수 있는 방법에 대한 연구의 일환으로서 기공의 응집,성장을 Potentiostat로 절연 파괴/ 전계 집중의 원리를 이용함으로서 소결도를 측정했다. 이 측정값은 각 온도에서 열처리한 시편에 대한 밀도값과 유사한 경향성이 나타남을 확인할 수 있었다. 개기공과 폐기공의 분포에 따라 예상될 수 있는 측정오차는 온도에 따른 미세구조의 변화를 수차례의 전자 현미경 관찰을 통해 확인하여I 미세규격 Rib 소결도의 판단을 전기화학적 방법으로 예측 가능 하다는 것을 알 수 있었다.

PbO-SiO_2계 유리에서의 유동 특성

차재민,김웅식,송현진,이병철,류봉기 釜山大學校生産技術硏究所 2002 生産技術硏究所論文集 Vol.61 No.-

유리에 관한 연구에 있어 점도는 가장 중요한 특성중의 하나로 여겨지며, 용융 상태, 작업 온도, 서냉 온도 또는 결정화 속도에 등과 같은 인자와도 크게 관계가 있다. 특히 각기 다른 조성을 가진 유리에서도 점도는 매우 다양하며, 온도에 크게 영향을 받는다. PbO-SiO_2 이성분계 유리에서는 PbO가 첨가됨에 따라 점도의 온도의존성이 커지고 표면장력이 감소하였다. 온도와 시간에 따른 spreading ratio를 비교한 결과 PbO의 함량이 증가함에 따라 유동성이 증가하였고 온도에 따른 유동성의 증가율도 크게 증가하였다. 그리고 일정한 온도에서 시간의 경과에 따른 유동성의 증가율은 감소하였다. The viscosity of a glass is one of the most important properties. It determines the melting conditions, the temperatures of working and annealing, fining behavior and devitrification rate. The viscosities of different glasses vary enormously with composition and are strong functions of temperature. On adding PbO in the PbO-SiO_2 binary system, the temperature dependence of the viscosity was large, the surface tension decreased. In the temperature and time dependence of spreading ratio, the spreading ratios of glass increased with increase PbO content and the rate in its increase decreased with time at constant temperature.

코치들의 직업관 및 근무환경에 관한 조사 연구

차봉준,조재기,이무진 東亞大學校 附設 스포츠科學硏究所 1997 스포츠科學硏究論文集 Vol.15 No.-

This study aims at examining the factors of professional consciousness and working conditions of coaches which is an urgent question of Pusan athletics, and giving the basic data for the improvement of thier positions and working conditions, when international sports games such as the Asian Games in 2002, the East Asian Games in '97. The World Cup in 2002 of joint auspices of Korea and Japan are invited and it is filled with a great deal of interest of sports than ever before and Pusan in riging as an international sports city. The subjects of examination were limited to 138 coaches who worked at elementary school, middle school, high school in Pusan. The way of analysis of data was intersection analysis and significance also was proved using Χ2 and signicance level was 0.05. The reliance coefficient of questionnaire was 0.6819 relatively high culculating CronBacha alpha value. The results of this study are as follows ; in the first place, in the professional conciousness, the motivation to have chosen choach job was "have aptitude for" which was highest. All answered positively to the questions ; Do you think choach job is the task of life? Do you have your firm view of teaching in coach job. Do you think coach job should be suited to your character and aptitude. Can you find your life worth living as choach? Do you have self-esteem as a choach"; and the professional consciousness of choaches was very high. but the question to players that do you want to be a choach was answered negatively. Second, in the working conditions, the teaching time of a day was positive but compensation system such as salary, stability of job, and private time, vacation or day off, was negative and it was proved that choach job don't gain public acceptance. But the relationship with director were all positive. In the items that should be developed for working conditions, the most answers were "gurantee of job in his life". The mediums that should impreve these problems prositvely were "school", "Education Board", "athletics association" in order. In the reasion of being content with choach job, the most answers were "for finding his life worth living as a choach" but in the reason of being discontent with choach job, the most answers were "no guaranting of status and the unstability of job". The salary that choach receives now was "athletics association", "school", and "parents of students" and "Education Board" in order. As the result above, in the factor of professional consciousness answers were greatly high and positive, but in the factor of working conditions there still remained problems of status guarantee, salary, compensation system, and thhe unstability of job.

폐 섬유 보강 복합재의 제조와 마찰특성

차준용,이정민,모상영,이재달,배기서,홍영기 忠南大學校 産業技術硏究所 1996 산업기술연구논문집 Vol.11 No.2

Fiber-reinforced composite materials are used in a wide variety of applications in the advanced field of industries such as electric clutch, motor, car, space and aviation etc. It is well known that the brake lining made of fiber-reinforced composites show excellent friction and wear properties compared to the conventional asbestos brakes and also are known to have high absorption energy and excellent high temperature properties in braking. In order to endow high friction and wear stability to the commercial brake lining, the waste fiber such as cotton, PAN, PET, nylon,kevlar, glass and it's binary mixture fibers were used the fiber reinforcements. The fiber/phenolic resin system has been carried out by preform molding method. The friction tester was especially designed and prepared for evaluation of frictional properties such as friction coefficient and stability. The physical properties of fiber reinforced composites were investigated in terms of the 3-point bending strength, the properties of friction, and morphology. The results obtained from the work are as follows ; 1. The friction properties of the cotton fiber reinforced composites were similar to those of the commercial brake linings, but in the cases of reinforcement of kevlar, glass. we can improve those properties, 2. The proper amount of organic and inorganic fiber mixtures can improve the properties of friction and the mechanical properties, 3. It is more desirable to manufacture hybrid fiber reinforced composites because single cotton or synthetic fiber reinforced composites aren't improved frictional properties, and 4. On evaluating frictional properties of waste fiber reinforced composites, frictional properties of waste fiber reinforced composites are superior to commercial disc lining. Therefore we can confirm practical possibility of waste fiber reinforced disc lining.

모자형단면 점용접부재의 축압궤특성에 관한 실험적 연구

차천석,김영남,심재기,김기형,양인영 朝鮮大學校 機械技術硏究所 2002 機械技術硏究 Vol.5 No.1

차량 전면충돌시 에너지흡수량이 가장 큰 차량전면부 사이드부재의 기본형상인 점용접된 단일모자형 단면부재에 대하여, 정적(0.00017m/sec), 준정적(0.017m/sec) 축방향 압궤실험을 행하였다. 이를 기초로 자체 제작한 수직식 공기압 충격실험장치를 이용하여 실제 차량이 충돌하는 것을 상정하여 충격속도 7.19m/sec(충격에너지 1034J)하에서 형상의 변화 및 폭비와 플랜지 용접간격의 변화에 따른 압궤특성을 고찰하여, 최적의 에너지 흡수성능을 갖는 구조부재에 대하여 검토하였다. The fundamentally and widely used spot welded sections of automobiles(hat and double hat shaped section members) absorb most of the energy in a front-end collision. The sections were tested on axial static(0.00017m/sec) and -quasi-staic(0.017m/sec) loads. Based on these test results, spcimens with various thicknesses, width ratios and spot weld pitches on the flange have been tested with high impact velocity(7.19m/sec 1034J) which imitate a real life car arash Characteristics of collapse have been reviewed and structures of optimal energy absorbing capacity is suggested.

腎疾患에서의 Cellulose Acetate 電氣泳動分劃에 對한硏究

宋基昌,朴在允,車德源,金昌世 朝鮮大學校 醫學硏究所 1979 The Medical Journal of Chosun University Vol.- No.-

Cellulose acetate electrophoretic studies of renal diseases were performed and the follo- wing results were obtained 1) The mean values for the electrophoretic fractions of serum protein in nephrotic syn- drome mere 1.18±0.48gm/100㎖(28.65±8.03%), 0.25±0.19 gn/100㎖ (5.05±3.17%)1.46±0.57 gn/100㎖(35.95±12.83%), 0.72±0.28 gn/100㎖(17.32±5.39%), and 0.56±0.21gm/100㎖(13.45±4.47%), respectively, for the albnmi, α_l-, α_2-, β-, and γ- globulin fractions. It was found that decrensed both albumin 2.11gm/100㎖(19a17%), and γ-glo-bulin, 0.94gm/100㎖(7.83%), fractions were more marked than in control groups. While α_2-globulin fraction was markedly increased, 0.7gm/100㎖(25.37%), to compare in control group. 2) The correlation coefficient between albumin and α_2-globulin fractions in nephrotic syndrome was γ=-0.84 and regression equation, was y=-1.34x-74.40. 3) The A/G ratio was markedly reversed as 0.40±0.16. 4) The mean values for the electrophoretic fractions of serum proteins in nonnephrotic syndrome, i. e. , acute and chronic glomerulonephritis, renal failure, pyelonephritis, and renal stones, were 2.35±0.59gm/100㎖(40.74±8.54%), 0.27±0.13gn/100㎖(4.65±1.98%), 0.78±0.25gm/100㎖(13.30±2.84%), 0.93±0.28gm/100㎖(15.75±4.33%), and 1.43±0.58gm/100㎖(24.14±8.14%), respectively, for the albumin, α_l-, α_2-, β-, and γ- globulin fractions. It was found that decreased albumin and increased α_l-globulin fractions were marked than in control group. 5) In the biochemical data in nephrotic syndrome it was found that serum cholesterol was increased. 2.5 times than in control group. In non-nephrotic syndrome group it was found that increased concentration of serum K and markedly increased concentration of serum creatinine(4.5 times) and BUN(3 times) were shown.

Hg₁-xMnxTe산화막의 홀효과에 관한 연구

오재근,최기영,송재흥,김영국,채건식,주유환,설정식,손인호,차성극,이상찬 慶南大學校 附設 基礎科學硏究所 1996 硏究論文集 Vol.8 No.-

HClO₄(pH:2) 수용액에서 양극산화 방법으로 HgMnTe(HMT)의 표면에 산화막을 형성 시켰다. 산화막의 두께는 SEM으로 측정하였으며 10㎛였다. 전류-전압 특성곡선을 얻어 산화 피크 전압으로부터 HTeO₂?, TeO?, HHgO₂? 막이 형성되었음을 알 수 있었다. 산화시키지 않은 HMT와 HClO₄수용액에서 산화시킨 HMT에 대해 Hall전압 및 자기저항을 각각 측정하였다. 홀전압과 자기저항은 HMT보다 HMT산화막에서 더 컸으며 이것은 HHgO₂? 공격자가 홀의 역할을 하고, TeO₄? 산화막은 전하의 포획도를 낮게하기 때문으로 생각할 수 있다. Anodic oxidation processes on HgMnTe surface has been studied in standard aqueous HClO₄(pH:2) solution. The 10㎛ thickness of the anodic oxide layers was measured by SEM. The Composition of the anodic oxide layers are evaluated from current-voltage(I-V) characteristic of HgMnTe Oxidation. The layers are composed of mixed oxide. ??, TeO₄, and?? in HClO₄solution. Transport properties have been investigated in HMT oxide layer made in HClO₄solution and virgin HMT samples at 300K. Hall voltage and magnetoresistance are greater in oxide layer HMT than virgin HMT. As a result, we know that the vacancy of ??in an anodic oxide layer acts as hole and the resulting oxide ?? layer exhibit a reduced degree of charge trapping and increase magnetoresistance.

腎疾患에서의 Cellulose Acetate 電氣泳動分劃에 對한 硏究

宋基昌,朴在允,車德源,金昌世 順天鄕大學校 1979 의대논문집 Vol.4 No.-

Cellulose acetate electrophoretic studies of renal diseases were performed and the following results were obtained : 1) The mean values for the electrophoretic fractions of serum protein in nephrotic syndrome were 1.18±0.48gm/100㎖(28.65±8.03%), 0.25±0.19gm/100㎖(5.05±3.17%)1.46±0.57gm/100㎖(35.95±12.83%), 0.72±0.28gm/100㎖(17.32±5.39%), and 0.56±0.21gm/100㎖(13.45±4.47%), respectively, for the albumi, a₁-, a₂-, β-, and r- globulin fractions. It was found that decrensed both albumin 2.11 gm/100㎖(19a17%), and r-globulin, 0.94gm/100.㎖(7. 83%), fractions were more marked than in control groups. While α₂-globlllin fraction was markedly increased, 0.7gm/100㎖(25.37%), to compare in control group. 2) The correlation coefficient between albumin and α₂-globulin fractions in nephrotic syndrome was r= -0.84 and regression equation was y= -1.34x+74.40. 3) The A/G ratio was markedly reversed as 0.40±0.16. 4) The mean values for the electrophoretic fractions of serum proteins in nonnephrotic syndrome, i. e., acute and chronic glomerulonephritis, renal failure, pyelonephritis, and renal stones, were 2.35±0.59gm/100㎖(40.74±8.54%), 0.27±0.13gm/100㎖(4.65±1.98%), 0.78±0.25gm/100㎖(13.30±2.84%), 0.93±0.28gm/100㎖(15.75±4.33%), and 1.43±0.58gm/100㎖(24.14±8.14%), respectively, for the albumin, a₁-, a₂-, β-, and r-globulin fractions. It was found that decreased albumin and increased α₁--globulin fractions were marked than in control group. 5) In the biochemical data in nephrotic syndrome it was found that serum cholesterol was increased 2.5 times than in control group. In non-nephrotic syndrome group it was found that increased concentration of serum K and markedly increased concentration of serum creatinine(4.5 times) and BUN(3 times) were shown.

트리스디에틸아미노수소화알루미늄 리튬의 합성과 환원특성

이재철,박기석,차진순,정승원 嶺南大學校附設 基礎科學硏究所 1988 基礎科學硏究 Vol.8 No.-

The stoichiometries and approximate rates on the reaction of representative organic compounds with a new reducing agent, lithium tris(diethylamino)aluminum hydride (LTDEA), prepared from the reaction of lithium aluminum hydride and 3 equivdiethylamine, have been examined systematically under the standardized conditions(THF,0℃) in order to characterize its reducing power. The introduction of dialkylamino group to LiAIH₄modifies the reducing characteristics of parent hydride. The reagent appears to be a mild, selective reducing agent. Especially, the reagent shows the possibility to reduce carboxylic acids, esters, amides, and nitriles. If the full scope of the reducing characteristics of this reagent has been completed, the utility in organic synthesis should be widely spread.