Elderly kidney transplant recipients have favorable outcomes but increased infection-related mortality

임정훈,Lee Ga Young,Jeon Yena,Jung Hee-Yeon,Choi Ji Young,CHO, JANG-HEE,Park Sun Hee,김용림,Kim Hyung-Kee,Huh Seung,유은상,Won Dong Il,Kim Chan-Duck 대한신장학회 2022 Kidney Research and Clinical Practice Vol.41 No.3

Background: The number of elderly patients with end-stage kidney disease has been increasing, but the outcomes of kidney transplants (KT) remain poorly understood in elderly patients. Therefore, we evaluated the clinical outcomes of elderly KT recipients and analyzed the impact of elderly donors. Methods: This retrospective cohort study included patients who underwent KT between 2000 and 2019. KT recipients were divided into four groups according to a combination of recipient and donor age (≥60 or <60 years); elderly recipients: old-to-old (n = 46) and young-to-old (n = 83); young recipients: old-to-young (n = 98) and young-to-young (n = 796). We compared the risks of mortality, graft failure, and acute rejection between groups using Cox regression analysis. Results: The incidence of delayed graft function, graft failure, and acute rejection was not different among groups. Annual mean tacrolimus trough level was not lower in elderly recipients than young recipients during 10-year follow-up. Mortality was significantly higher in elderly recipients (p = 0.001), particularly infection-related mortality (p < 0.001). In multivariable Cox regression analysis, old-toold and young-to-old groups had increased risk of mortality (adjusted hazard ratio [aHR], 2.89; 95% confidence interval [CI], 1.14– 7.32; p = 0.03; aHR, 3.06; 95% CI, 1.51–6.20; p = 0.002). However, graft failure and acute rejection risks were not increased in elderly recipients. Conclusion: In elderly recipients, graft survival and acute rejection-free survival were not inferior to those of young recipients. However, mortality, especially risk of infection-related death, was increased in elderly recipients. Thus, low immunosuppression intensity might help decrease mortality in elderly recipients.

Development of a Reduction Algorithm of GEO Satellite Optical Observation Data for Optical Wide Field Patrol (OWL)

Sun-youp Park,Jin Choi1,Jung Hyun Jo,Ju Young Son,Yung-Sik Park,Hong-Suh Yim,Hong-Suh Yim,Hong-Kyu Moon,Young-Ho Bae,Jang-Hyun Park 한국우주과학회 2015 Journal of Astronomy and Space Sciences Vol.32 No.3

An algorithm to automatically extract coordinate and time information from optical observation data of geostationary orbit satellites (GEO satellites) or geosynchronous orbit satellites (GOS satellites) is developed. The optical wide-field patrol system is capable of automatic observation using a pre-arranged schedule. Therefore, if this type of automatic analysis algorithm is available, daily unmanned monitoring of GEO satellites can be possible. For data acquisition for development, the COMS1 satellite was observed with 1-s exposure time and 1-m interval. The images were grouped and processed in terms of “action”, and each action was composed of six or nine successive images. First, a reference image with the best quality in one action was selected. Next, the rest of the images in the action were geometrically transformed to fit in the horizontal coordinate system (expressed in azimuthal angle and elevation) of the reference image. Then, these images were median-combined to retain only the possible non-moving GEO candidates. By reverting the coordinate transformation of the positions of these GEO satellite candidates, the final coordinates could be calculated.

산업자재용 폴리에스터 섬유의 강도 향상에 관한 연구

박영신,남영식,정상영,최재호,장기혁,박원호,Park, Young-Shin,Nam, Young-Sik,Jung, Sang-Young,Choi, Jae-Ho,Jang, Ki-Hyuk,Park, Won-Ho 한국섬유공학회 2012 한국섬유공학회지 Vol.49 No.1

In this work, effects of total draw ratio change on the mechanical properties of polyester fibers were studied. The process parameter was a total draw ratio and the draw ratios that were used ranged from 6.6 to 7.0. Tensile properties are determined from the tensile tester, and crystallite parameters from the density measurement and X-ray diffraction were discussed with the different total draw ratios. The tenacity, young's modulus and crystallinity were increased to 10.6 g/d, 123.2 g/d and 42.1%, respectively, with increase in the total draw ratio. The relations between total draw ratio and mechanical properties of high tenacity polyester fiber were discussed.

경포호의 어류상 및 어류군집 특성

최준길,박승철,장영수,이광열,최재석 강원대학교 부속 환경연구소 2005 Journal of the Environment Vol.2 No.-

The characteristics of ichthyofauna and fish community in the Lagoon Gyeongpo, Korea were investigated from May to October 2005. The total number of fish caught during the period was representing 26 specis and 18 families. Most dominant species was T. hakonensis(50.65%) and subdominant specis was A. flavimaus(25.41%). K. punctatatus(11.07%), M. cephalus(6.53%), E. japonicus(1.46%), C. castaneus(1.01%) were also numerous. The total biomass of collected fish showed 147.00kg, 135.83kg, 85.60kg,23.76kg, repectively. A pattern of the fish community according to seasonal veriations appear to be related tp spawning periods of species. Comparison of the ichthyofauna in present study with the references from early years suggests that there has been a gradual decrease, in composition, of primary freshwater specis accompanying with the increase of peripheral freshwater and seawater specis.

Aluminium板의 環境破壞에 關한 基礎的 硏究

崔壯宇,金榮萬,李龍福 弘益大學校 1982 弘大論叢 Vol.14 No.2

It is known that the most of Enviroment Assisted Fracture affected remarkably by the various environmental effect are brittle fracture, and that the above field is very wide. In this paper, Environment Assisted Fracture is discussed from the view point of fracture mechanics. Aluminium and SUS304 Stainless Steel in solutions of several percentage of MgCl₂(10%, 15%, 20%) at the temperature(60℃±3℃)is investigated according to the crack growth, and the value of K is compared with the K obtained by the changes of deflection according to the crack growth. THe results of the experiment is summarized as following 1)The tendency of crack growth as time goes by is shown as 4 region in both materials. 2)The experimental value of K of SUS304 Stainless Steel is same as the calculated value from the variation of the compliance according to crack growth, but not in Aluminium.

이산화된 탐색공간에서 다구찌 방법을 이용한 구조 최적설계에 관한 연구

장성현,정우영,정용민,권봉철,최영휴 한국공작기계학회 2008 한국공작기계학회 추계학술대회논문집 Vol.2008 No.-

Nowadays, there are several design problem having discrete variables in the industrial fields. The researchers are using the optimization method, such as genetic algorithm (GA), simulated annealing (SA), design of experiment (DOE) and taguchi method (TM), to solve it's design problem. Moreover, people want to decrease the computational cost and time. Therefore, in this paper, we proposed the iterative optimization algorithm which repetitively searched a local region to find best solution in discrete searching space using TM. The optimal solution in each local region is obtained by S/N ratio for the evaluation function that consists of the objective function and penalty function. Also, we have applied our algorithm to 3-bar, 10-bar, and 25-bar truss optimization problem.

복합레진의 수리 시 표면처리가 결합강도에 미치는 영향

최정인,김영재,김정욱,이상훈,김종철,한세현,장기택 大韓小兒齒科學會 2008 大韓小兒齒科學會誌 Vol.35 No.4

본 연구의 목적은 표면처리가 기존의 레진과 새로운 레진 사이의 전단결합강도에 미치는 영향을 평가하는 것이다. 준비된 레진 시편을 6군으로 임의로 배분하여 각각의 표면처리를 한 후 수리용 레진을 축조하였다. 일주일간 보관 후 전단결합강도를 측정하였고 일원분산 분석법으로 통계처리하여 다음과 같은 결과를 얻었다. 1. 3군과 4군(air abrasion)은 1군(산부식)에 비해 전단결합강도가 유의하게 높게 나타났다(p<0.005). 5군과 6군(diamond bur)은 1군(산부식)에 비해 높은 전단결합강도를 나타냈으나 통계적으로 유의하지 않았다(p<0.005). 2. 2군(자가부식 접착제)은 1군(산부식)에 비해 전단결합강도가 낮게 나타났으나 유의한 차이는 없었다(p<0.005). 3. 3군(air abrasion)과 4군(air abrasion +산부식)에서 전단결합강도의 차이는 유의하지 않았다(p<0.005). 4. 5군(diamond bur)과 6군(diamond bur+산부식)에서 전단결합강도의 차이는 유의하지 않았다(p<0.005). 결론적으로,복합레진의 수리 시 air abrasion으로 표면처리를 했을 때의 결합강도가 가장 높았고,산부식 방법과 처리여부는 수리강도에 유의한 영향을 미치지 않았다. The purpose of this study was to evaluate the effect of surface treatment on the shear bond strength between new and old composite resin. The prepared resin specimens were separated 6 groups, and each group then received a different surface treatment. Then the repair material was added. Shear bond strengths for repair were measured after 7 days and the results were analyzed by using one way ANOVA. The results were as follows ; 1. Group 3, 4(air abrasion) showed significantly higher shear bond strength than Group l (phosphoric acid)(p<0.05). Group 5, 6(diamond bur) showed higher bond strength than Group l(phosphoric acid) but not significantly different(p<0.05). 2. Group 2(self-etching adhesive) showed lower shear bond strength than Group 1 (phosphoric acid) but not significantly different (p<0.05). 3. There was no statistically significant difference between Group 3 (air abrasion) and Group 4(air abrasion + etching). 4. There was no statistically significant difference between Group 5(diamond bur) and Group 6(diamond bur+etching). In conclusion, the surface treatment with air abrasion resulted in higher repair bond strength than other methods. Repair bond strength was not significantly affected by acid etching.

평면 2자유도 모델을 이용한 리니어 모터로 구동되는 다축 마이크로 밀링머신 크로스헤드의 진동해석

장성현,황현영,정용민,최영휴,홍정표 한국공작기계학회 2008 한국공작기계학회 추계학술대회논문집 Vol.2008 No.-

In this paper, a simple 2-D.O.F. planar motion model is proposed in order to analyze the snake motion of a cross head assembly of a Multi-axis micro milling machine (M4) for BT-factory, that is travelling on linear guide. In the proposed mathematical model, the friction between head and guide ways is neglected, and also the support structures including the linear guides of M4 are assumed to be rigid. The equations of motion of the proposed model are derived and successfully solved to determine vibration responses of a cross head assembly due to some applied traction forces.

[논문]보양조건 및 타설주기를 고려한 매스 콘크리트 구조물의 수화열 해석

이영호,서기영,최덕락,엄장섭,진치섭* 釜山大學校生産技術硏究所 2004 生産技術硏究所論文集 Vol.63 No.-

콘크리트 구조물의 공용수명은 콘크리트 재료의 초기에 발생하는 수화열에 의해 아주 큰 영향을 받는다. 수화열은 콘크리트의 열전달 및 열응력 특성으로 결정되어지는 온도균열지수를 통해 분석되고 있다. 본 연구에서는 이러한 온도균열 지수의 분석을 통해 매스 콘크리트 구조물의 시공시 적절한 시벤트 종류, 보양방법,타설주기 및 타설높이 둥 최적의 시공방안 구하는데 도움을 주어 향후 시공 예정인 매스 콘크리트 구조물에 발생 가능한 온도균열을 미리 예측하여 이를 방지하기 위한 시공 방안을 제안하는데 그 목적을 두고 있다.

천연가스 사용 난방 및 산업보일러의 NOx와 CO 배출계수 산정 연구

장영기,최상진,김관,송기봉,김호정,정봉진 한국대기환경학회 2004 한국대기환경학회지 Vol.20 No.5

This study was conducted for developing the emission factors of nitrogen oxide(NOx) and carbon monoxide (CO) from the combustion boilers burning liquefied natural gas (LNG). These emission factors were compared with those of U.S. EPA and European Environment Agency (EEA). NOx and CO concentration in the flow gas were measured using Kane-May, KM9106 and Thermo Environmental Instruments Inc., 42C-HL. Measurement were conducted at thirty industrial and commercial LNG boilers. Emission factors were calculated on the basis of fuel consumption (kg-pollutant/㎥-fuel burned). NOx concentration at industrial boiler was 14~125 ppm and it was measured as 35~125 ppm at commercial boiler. NOx emission factors of industrial boiler and commercial boiler were 1.84kg/㎥ and 2.09kg/㎥, respectively. NOx emission factor of commercial boiler was higher than that of industrial boiler. The NOx emission factors estimated in this study were lower than those of U.S. EPA and higher than those of EEA. Average CO emission factor of industrial boiler was 0.65 kg/㎥ and at commercial boiler it was 0.70kg/㎥, CO emission factor at industrial boiler was lower than that at commercial boiler.