http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Kyuhyun Yoon,Jayeun Kim,Kyong Ran Peck,Hyun Soo Kim,Hyukmin Lee,Yoo-Sung Hwang,Soon Young Lee,Sung-il Cho,Hun Jae Lee,Yeong-gyeong Kim,Byoungguk Kim,June-Woo Lee,Ah-Ra Kim,Hyeon Nam Do,Dong-Hyun Kim 한국역학회 2022 Epidemiology and Health Vol.44 No.-
OBJECTIVES After the third wave of coronavirus disease 2019 (COVID-19), by mid-February 2021, approximately 0.16% of the Korean population was confirmed positive, which appeared to be among the lowest rates worldwide at that time. However, asymptomatic transmission is challenging for COVID-19 surveillance. Therefore, a community-based serosurvey of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was conducted to understand the effectiveness of Korea’s strong containment strategy. METHODS We collected 5,002 residual sera samples from January 30 to March 3, 2021, from 265 medical facilities in Seoul, 346 in Gyeonggi Province, and 57 in Incheon. Sixty samples from tertiary institutions were excluded. We defined the sub-regions according to the addresses of the medical facilities where the specimens were collected. Elecsys Anti-SARS-CoV-2 was used for screening, and positivity was confirmed using the SARS-CoV-2 sVNT Kit. Prevalence was estimated using sampling weights and the Wilson score interval for a binomial proportion with a 95% confidence interval. RESULTS Among the 4,942 specimens, 32 and 25 tested positive for COVID-19 in the screening and confirmatory tests, respectively. The overall crude prevalence of SARS-CoV-2 antibodies was 0.51%. The population-adjusted overall prevalence was 0.55% in women and 0.38% in men. The region-specific estimation was 0.67% and 0.30% in Gyeonggi Province and Seoul, respectively. No positive cases were detected in Incheon. CONCLUSIONS The proportion of undetected cases in Korea remained low as of early 2021. Therefore, an infection control strategy with exhaustive tracing and widespread pre-emptive testing appears to be effective in containing community spread of COVID-19.
Apolipoprotein(a) Kringles for Gene Therapy of Colon Cancer
Kyuhyun Lee,Sung-Tae Yun,Byung-Yoon Ahn,Eui-Cheol Jo 한국생물공학회 2019 Biotechnology and Bioprocess Engineering Vol.24 No.1
Lipoprotein(a) is a proatherogenic, prothrombotic lipoprotein that comprises apolipoprotein(a) (apo(a)) tethered to apolipoprotein B-100, which surrounds a lowdensity lipoprotein (LDL) moiety. Despite its molecular similarity to plasminogen, apo(a) plays distinct physiological and pathological roles both in vitro and in vivo. In this study, we examined possible target molecules and the therapeutic potential of gene therapy using a recombinant adeno-associated virus (AAV) carrying the LK8 and LK68 (LKs) genes, which encode the cryptic kringle fragment of apo(a) (rAAV-LK), for the treatment of colon carcinoma. The results showed that AAV-produced LKs inhibited the migration of HUVECs induced by different angiogenic factors in a dose-dependent manner, and the potency was >1,000-fold than that of recombinant LK8 and LK68 proteins. A single intramuscular injection of rAAV-LKs (1 × 109 infectious particles (IP)/mouse) significantly inhibited the growth of subcutaneously transplanted LS174T tumors and reduced the number of tumor nodules in metastasized livers. Immunohistochemical analysis showed that AAVproduced LKs inhibited microvessel formation within the tumor mass, thereby inducing apoptosis in the tumor periphery, leading to the suppression of both tumor growth and metastasis. Taken together, these results suggest that AAV-produced LKs are multi-potent angiogenesis inhibitors that suppress the growth and metastasis of colon carcinoma.
A Numerical Study on Performance of Air-to-Air Plastic Plate Heat Exchanger
Minho Chung,Seongyeon Yoo,Kyuhyun Han,Hongik Yoon,Hyoungchul Kang 대한설비공학회 2009 International Journal of Air-Conditioning and Refr Vol.17 No.2
The purpose of this research is to develop high efficiency plastic plate heat exchangers which can be substituted for conventional aluminum plate heat exchangers. Four simulation models of plastic plate heat exchangers are designed and simulated: that is, flat plate type, turbulent promoter type, corrugate type and dimple type heat exchanger. The flat plate type is designed as the reference model in order to evaluate how much thermal performance increases. The turbulent promoter type is fabricated with cylindrical-type vortex generators and rib-type turbulent promoters. The corrugate type is obtained from the conventional stainless steel compact heat exchangers, which are called the herringbone-type compact heat exchangers. The dimple type has a number of dimples on its surface. In this study, the flow and heat transfer characteristics of the plastic plate heat exchanger are investigated using numerical simulation and compared with experimental results. Numerical simulation is carried out using the FLUENT code. The flows are assumed as a three-dimensional, incompressible and turbulent model. The computational analysis and experimental results both show that the friction coefficient and Nu number is highest in the corrugate type. The tendency of numerical simulation results is in good agreement with that of the experimental results.