Integral Nonlinearity of Third Order Single Bit Sigma-Delta Modulator

Roman Kochan,Tomasz Ganczarczyk,Orest Kochan,Halyna Klym 제어로봇시스템학회 2016 제어로봇시스템학회 국제학술대회 논문집 Vol.2016 No.10

전문가 인터뷰

Thomas A. Kochan(토론자) 한국노동연구원 2004 국제노동브리프 Vol.2 No.3

미국 노동법과 노동정책의 원칙 및 대안에 관한 제언

Thomas A. Kochan 한국노동연구원 2018 국제노동브리프 Vol.16 No.11

Modeling of Hydrothermal Oxidation for Hazardous Wastes

Chang H. Oh,Robert J. Kochan 대한기계학회 1998 Heat transter conference Vol.7 No.1

Recombinant Human (rh)IL-4-Mediated Apoptosis and Recombinant Human IL-6-Mediated Protection of Recombinant Human Stem Cell Factor-Dependent Human Mast Cells Derived from Cord Blood Mononuclear Cell Progenitors

Oskeritzian, Carole A.,Wang, Zhiliang,Kochan, Janema P.,Grimes, Margaret,Du, Zhongmin,Chang, Hyeun-Wook,Grant, Steven,Schwartz, Lawrence B. 영남대학교 약품개발연구소 2000 영남대학교 약품개발연구소 연구업적집 Vol.10 No.-

Although stem cell factor(SCF) appears to be the major growth factor for human mast cells, other factors undoubtedly play important roles in the development, survival, and function of these cells. The current study examined the effects of recom-binant human(rh) IL-4 and rhIL-6 on rhSCF-dependent development and survival of human mast cells derived in vitro from cord blood progenitor cells. After 4-8 wk of culture with rhSCF and various amounts of rhIL-4, a dramatic decline in mast cell numbers was observed with rhIL-4, the EC_(50) being about 0.1ng/ml. Numbers of other cell types remained high. Mast cells derived from cord blood progenitors after 7 wk of culture with rhSCF alone displayed an MC_(T) phenotype and expressed Kit, FceRI, and IL-4R on their surface. Mast cells examined after purification by immunomagnetic sorting became apoptotic within hours after exposure to rhIL-4, a phenomenon blocked by anti-IL-4 Ab. Because rhIL-4-dependent apoptosis but not the loss of mitochondrial membrane potential potential was prevented by the pan-caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp-(Z-VAD)-fluoromethylketone, mitochondrial perturbation most likely preceded caspase activation. Consistent with this con-clusion was the observation that both apoptosis and loss of mitochondrial membrane potential(△Ψ_(m)) were inhibited by cyclosporin A in combination with aristolochic acid. rhIL-6 protected cord blood mast cells from rhIL-4-induced apoptosis. Thus, IL-4 can cause both maturation and apoptosis of human mast cells, the latter effect being abrogated by IL-6. The journal of Immunology, 1999, 163: 5105-5115.

활동기반 시뮬레이터 입력 자료의 전처리 방안에 대한 연구: FEATHERS Seoul을 사례로

조성진,황정환,Tom Bellemans,Bruno Kochan,이원도,최기주,조창현 대한교통학회 2014 大韓交通學會誌 Vol.32 No.5

ICAO에서 제시한 국가항공프로그램(State Safety Program, SSP)에 따르면, 국가의 항공안전 목표 달성을 위해 안전성과 측정 및 평가에 활용되는 안전성과지표(SPI)의 설정과 관리가 필수적이다. 이에 따라, 세계 여러 국가들은 자국의 실정에 맞는 SPI 수립을 연구개발하고 있다. 그에 반해, 우리나라는 2008년 국가항공안전프로그램이 제정된 이후로 지금까지 동일한 지표를 사용해왔으며, SPI 수립체계에 대한 체계적인 정책 사업 및 관련 연구가 미비한 실정이다. 따라서, 본 연구는 국내 SPI체계 개발의 일환으로 항공선진국인 유럽과 미국의 SPI 개발계획에 대한 동향 조사를 하고자 한다. 이를 위해 EU의 유럽항공안전국 (EASA), 영국의 민간항공국 (CAA), 핀란드의 교통안전국 (FTSA) 및 미국의 연방항공청 (FAA) 사례를 분석했다. 도출 결과를 기반으로 국내외 SPI 개발계획 및 수립체계의 차이점을 밝혔다. 본 연구를 통하여 도출된 분석 결과들은 향후 국내 SPI 수립체계의 발전방향 제시하기 위한 기틀을 마련할 수 있을 것이다. According to the State Safety Program (SSP) of the International Civil Aviation Organization (ICAO), it is essential to establish and manage Safety Performance Indicators (SPIs) which are used for monitoring the safety performance to achieve the national aviation safety goal. There have been enormous efforts to develop the framework of SPIs by considering the current status for each country. In case of Republic of Korea, however, there has been limited research and policy projects related to the framework for SPIs. Furthermore, Korea has used identical SPIs since the SSP was legislated in 2008. With this background, this research is, as part of strategy for the state level of SPI development, the study cases of advanced aviation countries for SPI development plans, such as the European Aviation Safety Agency (EASA) of the EU, the Civil Aviation Authority (CAA) of the UK, the Finish Transport Safety Agency (FTSA) of the Finland and the Federal Aviation Administration (FAA) of the U.S. The comparison between the foreign and domestic policies for SPI development strategies are provided in the conclusion of this study. The results and analyses of the case studies performed in this research will be helpful to provide some valuable development strategies for further SPI research in Korea.

Age-related cognitive decline and associations with sex, education and apolipoprotein E genotype across ethnocultural groups and geographic regions: a collaborative cohort study

Lipnicki, Darren M.,Crawford, John D.,Dutta, Rajib,Thalamuthu, Anbupalam,Kochan, Nicole A.,Andrews, Gavin,Lima-Costa, M. Fernanda,Castro-Costa, Erico,Brayne, Carol,Matthews, Fiona E.,Stephan, Blossom Public Library of Science 2017 PLoS medicine Vol.14 No.3

<▼1><P><B>Background</B></P><P>The prevalence of dementia varies around the world, potentially contributed to by international differences in rates of age-related cognitive decline. Our primary goal was to investigate how rates of age-related decline in cognitive test performance varied among international cohort studies of cognitive aging. We also determined the extent to which sex, educational attainment, and apolipoprotein E ε4 allele (<I>APOE*4</I>) carrier status were associated with decline.</P><P><B>Methods and findings</B></P><P>We harmonized longitudinal data for 14 cohorts from 12 countries (Australia, Brazil, France, Greece, Hong Kong, Italy, Japan, Singapore, Spain, South Korea, United Kingdom, United States), for a total of 42,170 individuals aged 54–105 y (42% male), including 3.3% with dementia at baseline. The studies began between 1989 and 2011, with all but three ongoing, and each had 2–16 assessment waves (median = 3) and a follow-up duration of 2–15 y. We analyzed standardized Mini-Mental State Examination (MMSE) and memory, processing speed, language, and executive functioning test scores using linear mixed models, adjusted for sex and education, and meta-analytic techniques. Performance on all cognitive measures declined with age, with the most rapid rate of change pooled across cohorts a moderate -0.26 standard deviations per decade (SD/decade) (95% confidence interval [CI] [-0.35, -0.16], <I>p</I> < 0.001) for processing speed. Rates of decline accelerated slightly with age, with executive functioning showing the largest additional rate of decline with every further decade of age (-0.07 SD/decade, 95% CI [-0.10, -0.03], <I>p</I> = 0.002). There was a considerable degree of heterogeneity in the associations across cohorts, including a slightly faster decline (<I>p</I> = 0.021) on the MMSE for Asians (-0.20 SD/decade, 95% CI [-0.28, -0.12], <I>p</I> < 0.001) than for whites (-0.09 SD/decade, 95% CI [-0.16, -0.02], <I>p</I> = 0.009). Males declined on the MMSE at a slightly slower rate than females (difference = 0.023 SD/decade, 95% CI [0.011, 0.035], <I>p</I> < 0.001), and every additional year of education was associated with a rate of decline slightly slower for the MMSE (0.004 SD/decade less, 95% CI [0.002, 0.006], <I>p</I> = 0.001), but slightly faster for language (-0.007 SD/decade more, 95% CI [-0.011, -0.003], <I>p</I> = 0.001). <I>APOE*4</I> carriers declined slightly more rapidly than non-carriers on most cognitive measures, with processing speed showing the greatest difference (-0.08 SD/decade, 95% CI [-0.15, -0.01], <I>p</I> = 0.019). The same overall pattern of results was found when analyses were repeated with baseline dementia cases excluded. We used only one test to represent cognitive domains, and though a prototypical one, we nevertheless urge caution in generalizing the results to domains rather than viewing them as test-specific associations. This study lacked cohorts from Africa, India, and mainland China.</P><P><B>Conclusions</B></P><P>Cognitive performance declined with age, and more rapidly with increasing age, across samples from diverse ethnocultural groups and geographical regions. Associations varied across cohorts, suggesting that different rates of cognitive decline might contribute to the global variation in dementia prevalence. However, the many similarities and consistent associations with education and <I>APOE</I> genotype indicate a need to explore how international differences in associations with other risk factors such as genetics, cardiovascular health, and lifestyle are involved. Future studies should attempt to use multiple tests for each cognitive domain and feature populations from ethnocultural groups and geographical regions for which we lacked data.</P></▼1><▼2><P>In a collaborative cohort study, Darren Lipnicki and colleagues investigate associations between age-related cognitive decline and sex, education, and apoli

An improved procedure for the development of human mast cells from dispersed fetal liver cells in serum-free culture medium

Kambe, Naotomo,Kambe, Michiyo,Chang, Hyeun-Wook,Matsui, Atsushi,Min, Hae-Ki,Hussein, Mousa,Oskeritzian, Carole A.,Kochan, Jarko,Irani, Anne-Marie A.,Schwartz, Lawrence B. 영남대학교 약품개발연구소 2000 영남대학교 약품개발연구소 연구업적집 Vol.10 No.-

The in vitro development of human mast cells from fetal liver cells with recombinant human stem cell factor in serum-containing RPMI was compared to that in AIM-V media with and without serum. Compared to serum-containing media, AIM-V media caused mast cells to develop earlier and in greater numbers. By 2 weeks, about 60% of cells in serum-free AIM-V medium were phenotypic mast cells, ~2 times the percentages in serum-containing media. By 6 weeks the percentages of mast cells were ≥80% under all conditions, but the number of mast cells was 3-4-fold greater in serum-free AIM-V medium than in serum-supplemented media. Mast cells obtained in serum-free AIM-V medium exhibited rounded nuclei, like tissue-derived mast cells; mast cells obtained in serum-supplemented media had segmented nuclei. By 10-12 weeks of culture about 40% of the AIM-V-derived cells showed strong chymase immunocytochemical staining, a pattern observed for only 14% of the cells in serum-containing media. AIM-V medium is a suitable medium for the development of human mast cells in vitro, and permits an earlier, more selective and greater expansion of mast cells than serum-containing media.