Source-Sink Partitioning of Mineral Nutrients and Photo-assimilates in Tomato Plants Grown under Suboptimal Nutrition

Jwakyung Sung,Suyeon Lee,Yejin Lee,Hongbae Yun,Sangkeun Ha,Yongsik Ok 한국토양비료학회 2013 한국토양비료학회지 Vol.46 No.6

A huge number of greenhouse soils in Korea have accumulated mineral elements which induce many nutritional and pathological problems. The present study was performed to the effects of the reduced fertilization on plant growth, and uptake and partitioning of minerals (N, P, K) and soluble carbohydrates using highly minerals-accumulated farmer’s greenhouse soil. On the basis of the recommended application for tomato crop, the application rates of N, P and K were 110(50%)-5.2(5%)-41.5(35%)kg ha<SUP>-1</SUP>, respectively, using Hoagland’s nutrient solution. Tomato growth rates during the whole experiment were not significant between treatments, but it was found that a decrease in daily growth represented after 60 days of treatment (DAT). The reduced application led to a drastic decrease in the concentration of N, P and K in fruits, and, thus, this resulted in lower uptake after 40 DAT. The lower phloem export and utilization of soluble carbohydrates caused an accumulation of extra-carbohydrates in leaves, stems and fruits in the reduced application. The reduced fertilization induced the capture of N, P and K in leaves and of soluble carbohydrates in stems compared to the conventional application. In this study, we suggest that it is possible to delay the first fertigation time in minerals-accumulated soils without an adverse impact on crop growth, but it is necessary to regularly monitor mineral status in soil to ensure a balanced uptake, synthesis and partitioning of minerals and carbohydrates.

Effect of Flow Rate on Smoke Control System for Railway Tunnel Fire

Yejin Ha(Yejin Ha),Joonho Jeon(Joonho Jeon) 한국화재소방학회 2023 International Journal of Fire Science and Engineer Vol.37 No.2

Tunnel is a semi-closed structure with a high risk of fire becuse of difficulty of smoke exhaust and restricted evacuation route in fire. No specific guidelines on smoke control systems have been developed for railway tunnels. Therefore, in the railway tunnel design, an average airflow velocity of 2.5 m/s inside a tunnel for the entry and exit of workers has been used as a reference. In this study, a fire simulation conducted to examine whether the average flow velocity can sufficiently apply on smoke control system in railway tunnel design. An 870-m-long railway tunnel with a single track and double track was modeled, and fire scenarios for light rail cars were simulated. It was found that the reference flow velocity showed sufficient smoke control performance, even at a maximum fire source of 60 MW. However, evacuees might be exposed to smoke due to the backlayer formed immediately. Furthermore, the smoke control performance for the reference velocity does not reflect the influence of the tunnel length. It is necessary to conduct a study on standard for appropriate smoke control performance to reduce fire risk in a railway tunnel fire.

Poly-Si 1T-DRAM의 Array 구조에서의 Disturbance 특성 분석

Yejin Ha,Wookyung Sun,Jisun Park,Hyungsoon Shin 대한전자공학회 2021 대한전자공학회 학술대회 Vol.2021 No.6

Immunomodulatory Effects of Extract from Pinus Koraiensis Cone Peel in vitro

Yejin HA,Minhee Lee,Jee-Yun Chang,Han Ol Kwon,Woojin Jun,Jeongmin Lee 한국식품영양과학회 2015 한국식품영양과학회 학술대회발표집 Vol.2015 No.8

Measurements of Location-Dependent Nitric Oxide Levels on Skin Surface in relation to Acupuncture Point

Ha, Yejin,Kim, Misun,Nah, Jiseon,Suh, Minah,Lee, Youngmi Hindawi Publishing Corporation 2012 Evidence-based Complementary and Alternative Medic Vol.2012 No.-

<P>Location-dependent skin surface's partial nitric oxide pressure (pNO) is studied using highly sensitive amperometric NO microsensor with a small sensing area (diameter = 76 <I><I>μ</I></I>m). The pNO level of LI4 (Hegu) acupuncture point is measured and compared with the pNO level of nonacupuncture point. In addition, the mapping of pNO is carried out over the left wrist skin area one- as well as two-dimensionally. Statistically higher pNO levels near the position of acupuncture points than non-acupuncture points are observed consistently, implying tight relationship between the level of NO release of skin and acupuncture points. The amperometric planar NO microsensor successfully monitors the heterogeneity of skin pNO distribution in high spatial resolution due to its advantageous features such as high sensitivity and small sensing dimension. The current study suggests the direct connection between NO and acupuncture points and possibly provides beneficial information to understand physiological roles and basis of the acupuncture points.</P>

Anti-inflammatory Effect of Extract from Pinus Koraiensis Cone Peel on the Lipopolysaccharide-induced Inflammation in Mouse Model

Yejin HA,Minhee Lee,Jee-Yun Chang,Han Ol Kwon,Woojin Jun,Jeongmin Lee 한국식품영양과학회 2015 한국식품영양과학회 학술대회발표집 Vol.2015 No.8

Parental intention to vaccinate daughters with the human papillomavirus vaccine in Korea: a nationwide cross-sectional survey

Yejin Ha,Kyeongmin Lee,Bomi Park,Mina Suh,Jae Kwan Jun,Kui Son Choi 한국역학회 2023 Epidemiology and Health Vol.45 No.-

OBJECTIVES: We aimed to identify and compare the characteristics and factors associated with parental intention to vaccinate daughters under 12 years old against human papillomavirus (HPV), examining data from 2016 and 2020. METHODS: Data were obtained from the Korean National Cancer Screening Survey conducted in 2016 and 2020. The present study included 3,510 parents with daughters under 12 years old. Changes in parental intention-to-vaccinate rates were calculated. To identify factors associated with parental intention to vaccinate their daughters, the chi-square test and logistic regression analysis were used. RESULTS: The percentage of respondents intending to vaccinate their daughters increased from 33.4% in 2016 to 58.9% in 2020, constituting a 25.5 percentage point (%p) increase. Since 2016, the proportion of men expressing positive intention towards HPV vaccination increased by 31.5%p, while that of women demonstrated a 20.9%p increase. Logistic regression analysis indicated that parents with a strong intention to vaccinate their daughters tended to be younger, more educated, and aware of the free vaccination program available, as well as to have a history of HPV vaccination and to have undergone cervical cancer screening within 2 years, compared to those who did not intend to vaccinate. Being a mother with a history of HPV vaccination was the strongest predictor of positive intention to vaccinate a daughter. CONCLUSIONS: The intention among parents to vaccinate daughters remains relatively low, although it is rising. To increase the HPV vaccination rate, strong recommendations and education should be provided to parents and the younger generation.

화재 시뮬레이션을 이용한 다중 연료 적용에 대한 검토

하예진(Yejin Ha),전준호(Joonho Jeon) 한국화재소방학회 2022 한국화재소방학회 학술대회 논문집 Vol.2022 No.춘계

연료는 연소의 4요소 중 가연물에 해당하며 고체연료, 기체연료, 액체연료 등 다양한 형태의 연료가 존재한다. 연료는 구성 성분에 따라 단일 물질로만 이루어진 연료가 있고 다중 물질로 이루어진 연료도 있다. 하지만, 대부분의 수치해석 연구는 단일 연료를 적용하여 화재를 해석하고 있다. 최근 FDS(Fire Dynamics Simulator)에서는 다중 연료를 구현할 수 있는 기능을 추가하였다. 따라서 본 연구에서는 다중 연료를 해석한 기존 연구를 분석하여 화재 시뮬레이션을 통해 단일 연료로만 해석한 경우와 다중 연료로 해석한 경우의 시뮬레이션 결과와 기존 연구결과를 비교하여 다중 연료 적용에 대해 검토하고자 한다. 또한, 다중 연료 중 한 연료의 구성 성분비 변화가 온도, 농도 등에 미치는 영향을 세부적으로 분석하고자 한다. 본 연구결과가 화재 시뮬레이션에서의 다중 연료 적용을 위한 기초자료로 사용할 수 있을 것으로 기대한다.

울금 주정 추출물이 자연살해세포와 T 면역세포에 미치는 영향

하예진(Yejin Ha),김옥경(Ok-Kyung Kim),남다은(Da-Eun Nam),김용재(Yongjae Kim),김은(Eun Kim),전우진(Woojin Jun),이정민(Jeongmin Lee) 한국식품영양과학회 2015 한국식품영양과학회지 Vol.44 No.3

본 연구에서는 국내에서 재배되는 울금의 면역조절 효과에 대해 평가하고자 20% 주정 추출물을 이용하여 자연살해세포와 T 세포에 미치는 영향을 관찰하였다. 마우스의 비장세포에서 분리한 자연살해세포를 종양세포 YAC-1 세포와 함께 배양시켜 울금 20% 주정 추출물의 처리에 따른 변화를 관찰하였다. 그 결과 울금 20% 주정 추출물의 처리는 자연살해세포의 CD69 발현과 IFN-γ의 발현을 증가시켰고 결과적으로 활성이 증가되어 YAC-1 세포의 제거를 증가시켰음을 확인하였다. 또한 마우스의 비장세포에서 울금 20% 주정 추출물의 처리에 따른 T 세포의 변화를 관찰한 결과에서는 CD4+ T 세포보다는 CD8+ T 세포를 증가시켰음을 확인하여 감염된 세포나 종양세포 제거를 효과적으로 할 수 있을 것이라고 예상할 수 있었다. 결론적으로 울금 20% 주정 추출물은 내재면역과 적응면역에 영향을 미쳐 면역조절에 긍정적인 변화를 보였음을 확인하였다. The present study investigated the immunomodulatory effects of Curcuma longa L. ethanol extracts on natural killer (NK) cells and T cells. We treated Curcuma longa L. ethanol extracts at concentrations of 20, 50, 100, and 150 μg/mL to murine NK cells co-incubated with YAC-1 cells. Curcuma longa L. ethanol extracts resulted in increased NK cell activity compared to the control group at all concentrations. In the groups treated with Curcuma longa L. ethanol extracts, CD69 and IFN-γ expression levels significantly increased compared to the control group at 100 and 150 μg/mL. In addition, Curcuma longa L. ethanol extracts induced significant elevation of CD8+ T cell numbers in a dose-dependent manner. However, Curcuma longa L. ethanol extracts also led to reduction of CD4+ T cell and MHCⅡ numbers. The findings of this study suggest that Curcuma longa L. ethanol extracts could enhance the immune response through activation of NK and cytotoxic T cells due to a proliferative shift of antigen presentation from MHCⅡ to MHCⅠ, presumably.

장대터널 내 대형화재 발생 시 제연설비 성능 확보를 위한 수치적 연구

하예진(Yejin Ha),전준호(Joonho Jeon) 한국화재소방학회 2022 한국화재소방학회논문지 Vol.36 No.6

본 연구에서는 장대 터널 내 대형화재 시 제연설비 성능을 세부적으로 검토하기 위해 fire dynamics simulator를 이용하여 전산시뮬레이션을 수행하였다. 항만 지역에 위치해 물류 이동이 많은 지역 터널을 기반으로 한 장대 터널을 시뮬레이션 대상으로 선정하였다. 화재 시나리오는 기존 실규모 실험 연구 데이터를 바탕으로 하여 대형화재에 해당하는 화물차량 화재로 설정하였다. 지역 터널에서 사용하는 내경이 1250 mm인 제트팬을 시뮬레이션 터널에 동일하게 적용시켰다. 적절한 제연설비 성능을 확보하기 위해, 제트팬 유량 및 설치 간격의 변화가 연기 거동, 가시거리, 온도에 미치는 영향을 분석하였다. 제트팬 유량이 감소할수록 긴 역기류가 나타났으며, 인명 안전 기준에 도달하는 시간이 빨라졌다. In this study, a numerical simulation was performed using the fire dynamics simulator to examine the performance of a smoke control system in the case of a large fire in a long tunnel. A regional long tunnel that facilitates frequent movement in the port area was simulated. The fire scenario was set as a heavy goods vehicle fire corresponding to a large fire based on the existing real-scale experimental research data. A jet fan with an inner diameter of 1250 mm used in the regional tunnel was included in the tunnel simulation. For the evaluation of the smoke control system performance, the effects of the flow rate and installation interval of the jet fan on the smoke behavior, visibility, and temperature was analyzed. As the flow rate of the jet fan decreased, backlayering was lengthened, which reduced the time to achieve life safety standard.