• Transactions on Electrical and Electronic Materials
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• 제15권5호
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• pp.235-240
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• 2014

Nanocomposites made of linear low density polyethylene (LLDPE) and organo-modified montmorillonite (O-MMT) were processed by melt compounding from a commercially available premixed LLDPE/nanoclay masterbatch, at different nanoclay loadings, by co-rotating twin-screw extruder. The morphological and dielectric properties of LLDPE/O-MMT nanocomposites were investigated to understand the structure-dielectric properties relationship in the nanocomposites. The microstructures of the materials were characterized by wide angle X-ray diffraction (WAXD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM). Initial findings by FTIR spectroscopy characterization indicated the absence of any chemical interaction between LLDPE and nanoclay during the extrusion process, while DSC showed that a 1% wt loading of nanoclay particles increased the degree of crystallinity of the nanocomposites samples. On the other hand, XRD, SEM, TEM and AFM indicated that nanoclay layers were intercalated or exfoliated in the LLDPE matrix. A correlation between the structure and dielectric properties of LLDPE/O-MMT nanocomposites was found and discussed.

• Transactions on Electrical and Electronic Materials
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• 제16권2호
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• pp.53-61
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• 2015

High-energy ball milling was tested as a method for producing Ultra High Molecular Weight Polyethylene (UHMWPE)- based nanodielectrics containing 1 wt% and 5 wt% OctaIsoButylPOSS (OibPOSS). Qualitative and quantitative evaluations were used to explore the compatibility between OibPOSS and PE. Several ball milling variables were optimized in a bid to achieve UHMWPE/OibPOSS nanodielectrics. The morphology, as well as the thermal and the dielectric properties of the samples, were characterized by scanning electron microscopy, thermogravimetric analysis, broadband dielectric spectroscopy, and progressive-stress breakdown tests. The results showed that (i) ball milling was an effective method for producing UHMWPE/OibPOSS dielectric composites, but appeared ineffective in dispersing OibPOSS at the nanoscale, and (ii) the resulting UHMWPE/OibPOSS dielectric composites presented thermal and dielectric properties similar to those of neat UHMWPE.

• Smart Structures and Systems
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• 제20권5호
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• pp.525-537
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• 2017

This paper explores different vibration control strategies for the cancellation of human-induced vibration on a structure with time-varying modal parameters. The main motivation of this study is a lively urban stress-ribbon footbridge (Pedro $G\acute{o}mez$ Bosque, Valladolid, Spain) that, after a whole-year monitoring, several natural frequencies within the band of interest (normal paring frequency range) have been tracked. The most perceptible vibration mode of the structure at approximately 1.8 Hz changes up to 20%. In order to find a solution for this real case, this paper takes the annual modal parameter estimates (approx. 14000 estimations) of this mode and designs three control strategies: a) a tuned mass damper (TMD) tuned to the most-repeated modal properties of the aforementioned mode, b) two semi-active TMD strategies, one with an on-off control law for the TMD damping, and other with frequency and damping tuned by updating the damper force. All strategies have been carefully compared considering two structure models: a) only the aforementioned mode and b) all the other tracked modes. The results have been compared considering human-induced vibrations and have helped the authors on making a decision of the most advisable strategy to be practically implemented.

• Journal of Trauma and Injury
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• 제28권1호
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• pp.1-8
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• 2015

Purpose: The purposes of this study are finding the elements for a fast determination of the need for a transfusion to a multiple trauma patient arriving at this clinic in the initial stage establishing objective bases for a doctor in an emergency department to determine the need for a transfusion immediately after a patient has arrived at the emergency department, and providing treatment by considering various factors based on the nine criteria suggested in the emergency room transfusion score (ETS). Methods: This study was conducted on 375 multiple-trauma patients who visited the Chosun University Hospital Emergency Medical Center and activated the Emergency Trauma Team from January 2010 to December 2013. The patients were divided into the transfused group and the non-transfused group by retrospectively analyzing their medical records. Subsequently, the medical records were examined using the nine items suggested by the ETS and the results were analyzed. Results: Three hundred seventy-five patients with multiple traumas visited the Chosun University Hospital Emergency Medical Center and activated the Emergency Trauma Team. Among them, 258 died and 117 recovered and left the hospital. The deceased patients consisted of 182 males and 76 females with an average age 45. Of the 375, 165 were transferred from other hospitals, and 245 were blunt trauma patients. One hundred sixty-nine patients were injured in traffic accidents, and 119 of those 169 who had systolic blood pressure less than 90 mm Hg died. Two hundred twenty-six (60.3%) out of the 375 patients with multiple traumas received an emergency blood transfusion and their average age was 48. The 375 patients consisted of 156 males, 151 who had been transferred from other hospitals, 218 who presented with blunt trauma, 134 who had been injured in traffic accidents, 156 who had a systolic blood pressure less than 90 mm Hg, 134 who scored higher than 9 points on the GCS, and 162 who had a stable pelvic fracture of these 143 died. Conclusion: During this study, 226 (60.3%) out of the patients with multiple traumas received an emergency blood transfusion. After analyzing the results related to emergency blood transfusion by using ETS, we found that an emergency blood transfusion had to be prepared quickly when patients were transferred from other hospitals when the systolic blood pressure was less than 90 mmHg. when abnormalities had been detected by ultrasonography and when the patient presented with a stable pelvic fracture.

• 자원ㆍ환경경제연구
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• 제28권3호
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• pp.385-413
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• 2019

본 연구는 유럽 30개 국가들을 대상으로 1990~2014년 동안의 패널 자료를 이용하여 유럽이 탄소배출권 거래시장을 도입한 2005년을 기준으로 도입 전과 후로 나누어 유럽 내 연결계통국가들의 전력 순수출 변화 결정요인을 이분산과 자기상관 문제를 고려한 패널 GLS 방법으로 추정하였다. 종속변수로는 전력 순수출량이 사용되었으며 설명변수로는 발전원별 발전량 비중, 이웃 국가들의 자국 내 전력수급, 에너지자원 보유국의 전력 생산량, 발전원 집중도 그리고 산업부문의 1인당 총에너지사용량 등을 사용하였다. 추정결과에 의하면, 2005년 이전과 이후 모두에서 에너지자원 보유국의 전력생산량과 발전원 집중도, 원자력 발전비중은 전력 순수출에 통계적으로 유의미하게 양(+)의 영향을 미쳤으며, 탄소배출권 거래제 도입 이후에 그 중요도는 증가하는 것으로 나타났다. 반면 이웃 국가들의 자국 내 전력수급과 산업부문의 1인당 총 에너지사용량, 재생에너지 발전비중은 통계적으로 유의하게 음(-)의 영향을 미치는 것으로 추정되었다. 석탄과 가스 발전비중의 경우에는 2005년 이전에만 통계적으로 유의미하게 전력 순수출에 음(-)의 영향을 미쳤다. 본 연구결과는 국가 간 전력교역상황에서 개별 국가들의 역할을 결정하는 요인이 무엇이며 그에 맞는 중 장기 전원믹스 방안을 도출하는 데 시사점을 제시하고 있다.

• 분석과학
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• 제16권4호
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• pp.299-308
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• 2003

실내 사무환경에 대해 흡연환경에 따라 흡연실, 흡연 허용 사무실, 비흡연사무실, 흡연실 인접 지역 등을 대상으로 ETS 중 발암물질인 카드뮴을 포함한 금속류, 니코틴, 3-EP, 호흡성먼지등 지표물질의 농도분포와 이의 분포에 영향을 주는 흡연밀도, 흡연지수 등을 조사하여 그 상관성을 파악하였다. 공기교환횟수는 흡연실과 흡연허용사무실에서 각각 평균 11.1, 4.6 회/시간을 나타냈으며, 흡연밀도는 최고 $2.6cig/m^2{\cdot}hr$에서부터 최저 $0.2cig/m^2{\cdot}hr$로 나타났다. 금속류 중 카드뮴은 기하정규분포를 보였으며 흡연환경별 기하평균 농도가 흡연실에서 $0.045{\mu}g/m^3$, 흡연실 인근 지역에서 $0.018{\mu}g/m^3$, 흡연허용사무실에서 $0.021{\mu}g/m^3$, 비흡연사무실에서는 $0.017{\mu}g/m^3$의 분포를 보였으며 통계적으로는 유의한 차이를 나타냈다(p<0.05). 실내 흡연 환경에 따른 카드뮴의 농도 비를 조사한 결과 비흡연실 기준으로 흡연실에서 2.6배, 흡연허용사무실에서 1.2배의 농도 분포를 보였다. 카드뮴과 지표물질간 상관성을 조사한 결과 니코틴과의 상관계수가 0.53 (p<0.001)으로 가장 높게 나타났으며 호흡성먼지와는 0.43, 3-EP와는 가장 낮은 0.41의 상관계수 값을 보였으며, 흡연 밀도와는 0.54 (P<0.001), 흡연지수와는 0.63(p<0.001)의 상관계수 값을 보였다. 이러한 연구 결과를 토대로 ETS 중 중금속류에서는 카드뮴을 지표물질로 활용할 수 있다고 판단할 수 있다.

• 한국농공학회논문집
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• 제47권1호
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• pp.3-9
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• 2005

The purpose of this study was to analyze the climatic water balance of the Korean peninsula using meteorological data and the evapotranspiration (ET) derived from NOAA/AVHRR, Quantifying water balance components is important to understand the basic hydrology, In this study, a simple method to estimate actual ET was proposed based on a regression approach between NDVI and Morton's actual ET using NOAA/AVHRR data, The Mortons actual ET for land surface conditions was evaluated using a daily meteorological data from 77 weather stations, and the monthly averaged Morton's ETs for each land cover was compared with the monthly NDVIs during the year 2001. According to the climatic water balance analysis, water deficit and surplus distributed maps were created from spatial rainfall, soil moisture, and actual and potential ETs map, The results clearly showed that the temporal and spatial characteristics of dryness and wetness may be detected and mapped based on the wetness index.

• Journal of Periodontal and Implant Science
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• 제40권1호
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• pp.39-44
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• 2010

Purpose: Bone tissues for clinical application can be improved by studies on osteoblast differentiation. Runx2 is known to be an important transcription factor for osteoblast differentiation. However, bone morphogenetic protein (BMP)-2 treatment to stimulate Runx2 is not sufficient to acquire enough bone formation in osteoblasts. Therefore, it is necessary to find other regulatory factors which can improve the transcriptional activity of Runx2. The erythroblast transformation-specific (ETS) transcription factor family is reported to be involved in various aspects of cellular proliferation and differentiation. Methods: We have noticed that the promoters of osteoblast differentiation markers such as alkaline phosphatase (Alp), osteopontin (Opn), and osteocalcin (Oc) contain Ets binding sequences which are also close to Runx2 binding elements. Luciferase assays were performed to measure the promoter activities of these osteoblast differentiation markers after the transfection of Runx2, myeloid Elf-1-like factor (MEF), and Runxs+MEF. Reverse-transcription polymerase chain reaction was also done to check the mRNA levels of Opn after Runx2 and MEF transfection into rat osteoblast (ROS) cells. Results: We have found that MEF, an Ets transcription factor, increased the transcriptional activities of Alp, Opn, and Oc. The addition of Runx2 resulted in the 2- to 6-fold increase of the activities. This means that these two transcription factors have a synergistic effect on the osteoblast differentiation markers. Furthermore, early introduction of these two Runx2 and MEF factors significantly elevated the expression of the Opn mRNA levels in ROS cells. We also showed that Runx2 and MEF proteins physically interact with each other. Conclusions: Runx2 interacts with MEF proteins and binds to the promoters of the osteoblast markers such as Opn nearby MEF to increase its transcriptional activity. Our results also imply that osteoblast differentiation and bone formation can be increased by activating MEF to elicit the synergistic effect of Runx2 and MEF.

• 대한한방종양학회지
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• 제4권1호
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• pp.131-146
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• 1998

To examine the effect of Shiquandabutang on the metastasis of cancer, the following experiments were made. Before the main experiments, the cytotoxicity was measured by putting Shiquandabutang sample in HT1080. Then zymography was made to examine the change of gelatinolytic activity. And western blotting was carried out to examine the changes of Fos, Jun, Ets, the transcription factors of MMP-2, MMP-9, and Erk, JNK on signal transduction pathway to AP-1. Third, in vitro invasion assay with transwells coated by collagen and matrigel was carried out. From the results of the above the following conclusions were obtained. 1. The experimental result about cytotoxicity of Shiquandabutang against HT1080 was as below. The stained cell count after being treated by Shiquandabutang sample $400{\mu}g/ml$ for 24 hours was 0.9% of total cells, and the stained cell count by Shiquandabutang sample $100{\mu}g/ml$ was 1.5% of total cells. Both were near the level of control group which showed 0.6% stained. 2. The result of collagenase assay was as below. In Shiquandabutang sample $400{\mu}g/ml$, MMP-2 was reduced as compared with TPA control group, and the band of MMP-9 induced by TPA disappeared. In Shiquandabutang sample $800{\mu}g/ml$, both bands of MMP-2 and MMP-9 disappeared. 3. The results of western blots for Jun, Fos, Ets, Erk, JNK were as below. In Shiquandabutang sample $200{\mu}g/ml$, Ets was reduced, and Fos were increased. 4. The result of invasion assay was as below. The number of cells which migrated across transwell membrane in Shiquandabutang-treated group was less than that of +TPA control group. From the above results, it was concluded that Shiquandabutang might control the appearing and acting of collagenase not by the MMP-2, -9 promoter but by other way.

• Asian-Australasian Journal of Animal Sciences
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• 제33권3호
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• pp.398-407
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• 2020

Objective: The Yip1 domain family (YIPF) proteins were proposed to function in endoplasmic reticulum (ER) to Golgi transport and maintenance of the morphology of the Golgi, which were homologues of yeast Yip1p and Yif1p. YIPF3, the member 3 of YIPF family was a homolog of Yif1p. The aim of present study was to investigate the expression and regulation mechanism of porcine YIPF3. Methods: Quantitative realtime polymerase chain reaction (qPCR) was used to analyze porcine YIPF3 mRNA expression pattern in different tissues and pig kidney epithelial (PK15) cells stimulated by polyinosine-polycytidylic acid (poly [I:C]). Site-directed mutations combined with dual luciferase reporter assays and electrophoretic mobility shift assay (EMSA) were employed to reveal transcription regulation mechanism of porcine YIPF3. Results: Results showed that the mRNA of porcine YIPF3 (pYIPF3) was widely expressed with the highest levels in lymph and lung followed by spleen and liver, while weak in heart and skeletal muscle. Subcellular localization results indicated that it expressed in Golgi apparatus and plasma membranes. Upon stimulation with poly (I:C), the level of this gene was dramatically up-regulated in a time- and concentration-dependent manner. pYIPF3 core promoter region harbored three cis-acting elements which were bound by ETS proto-oncogene 2 (ETS2), zinc finger and BTB domain containing 4 (ZBTB4), and zinc finger and BTB domain containing 14 (ZBTB14), respectively. In which, ETS2 and ZBTB4 both promoted pYIPF3 transcription activity while ZBTB14 inhibited it, and these three transcription factors all played important regulation roles in tumorigenesis and apoptosis. Conclusion: The pYIPF3 mRNA expression was regulated by ETS2, ZBTB4, and ZBTB14, and its higher expression in immune organs might contribute to enhancing ER to Golgi transport of proteins, thus adapting to the immune response.