The Effect of Pulsatility Index on Infarct Volume in Acute Lacunar Stroke

Kim, Yoon,Lee, Hanbin,An, Se-A,Yim, Byeongsoo,Kim, Jonguk,Kim, Ok Joon,Kim, Won Chan,Kim, Hyun Sook,Oh, Seung Hun,Kim, Jinkwon Yonsei University College of Medicine 2016 Yonsei medical journal Vol.57 No.4

<P><B>Purpose</B></P><P>Lacunar stroke, in the context of small vessel disease, is a type of cerebral infarction caused by occlusion of a penetrating artery. Pulsatility index (PI) is an easily measurable parameter in Transcranial Doppler ultrasound (TCD) study. PI reflects distal cerebral vascular resistance and has been interpreted as a surrogate marker of small vessel disease. We hypothesized that an increased PI, a marker of small vessel disease, might be associated with a larger infarct volume in acute lacunar stroke.</P><P><B>Materials and Methods</B></P><P>This study included 64 patients with acute lacunar stroke who underwent TCD and brain MRI. We evaluated the association between the mean PI value of bilateral middle cerebral arteries and infarct volume on diffusion-weighted MRI using univariate and multivariate linear regression.</P><P><B>Results</B></P><P>The mean infarct volume and PI were 482.18±406.40 mm<SUP>3</SUP> and 0.86±0.18, respectively. On univariate linear regression, there was a significant positive association between PI and infarct volume (<I>p</I>=0.001). In the multivariate model, a single standard deviation increase of PI (per 0.18) was associated with an increase of 139.05 mm<SUP>3</SUP> in infarct volume (95% confidence interval, 21.25 to 256.85; <I>p</I>=0.022).</P><P><B>Conclusion</B></P><P>We demonstrated that PI was an independent determinant of infarct volume in acute lacunar stroke. The PI value measured in acute stroke may be a surrogate marker of the extent of ischemic injury.</P>

석유화학 공장 사무실 공기질과 근로자 자각 증상과의 연관성에 관한 연구

김기연(Kiyoun Kim),김혜정(Hyejung Kim),김현수(Hyunsoo Kim),김치년(Chinyon Kim),원종욱(Jonguk Won),노영만(Youngman Roh),노재훈(Jaehoon Roh) 한국실내환경학회 2006 한국실내환경학회지 Vol.3 No.3

This research was performed with the subject of 111 offices in a chemical plant of Korea. Airborne concentration level of carbon dioxide, carbon monoxide, formaldehyde and total suspended particulates in the office rooms were measured along with temperature and relative humidity. Simultaneously, general characteristics and subjective health symptoms of 500 office workers were investigated through a questionnaire consisting of the five point weighting method : 0 = not at all, 1 = a little bit, 2 = moderately, 3 = quite a bit and 4 = extremely. Results showed that the mean values for temperature and relative humidity in investigated office rooms were 22.2℃ and 34.3%, respectively. The concentrations of formaldehyde, PM10, carbon dioxide and carbon monoxide were 0.17 ppb, 28.8 ㎍/㎥, 0.95 ppm and 424 ppm, respectively. 56.4% of all the workers investigated replied with a sense of fatigue or weariness (mean=2.23), drowsiness or languidness (mean=2.22), sneezing (mean=2.11) and ophthalmia oreye fatigue (mean=2.07). Female workers, non-smokers, non-drinkers, workers who do shift more than nine hours a day, and workers in poor health experienced more subjective symptoms than other workers (p<0.05). Subjective symptoms of office workers were significantly associated with the following items of office characteristics: the purchase date of office equipment, the change of office furniture, the use of paint, smoking in the office, ventilation condition, the use of an individual air-conditioner, the use of a fax machine, the degree of office repair, the proportion of workers per office, the degree of satisfaction in office environment, and the operation hours of the air-conditioner. Also, subjective symptoms were positively correlated with indoor environmental factors such as relative humidity, carbon dioxide level, level of PM10, and formaldehyde (p<0.05). In conclusion, office characteristics and air quality in a chemical plant affected subjective health symptoms of office workers. Thus, in order to improve the health of workers, to enhance work efficiency, and to establish a better office environment, air quality control in office rooms by optimal ventilation, adequately occupied number of workers in one office, and maintenance of office equipment should be fulfilled thoroughly.

PZT 파우더 첨가에 따른 티타늄 파우더/폴리머 콘크리트 복합재료의 진동 특성 및 압축 물성 분석

박재현,김석룡,김경수,김건,김석호,이범주,정안목,안종욱,김선주,이시맥,유형민,Park, Jaehyun,Kim, Seok-Ryong,Kim, Kyoung-Soo,Kim, Geon,Kim, Seok-Ho,Lee, Beom-Joo,Jeong, Anmok,An, Jonguk,Kim, Seon Ju,Lee, Si-Maek,Yoo, Hyeong-Min 한국복합재료학회 2022 Composites research Vol.35 No.3

In this study, Ti powder/Polymer concrete composites were processed by adding the PZT powder, one of the piezoelectric materials, to improve the vibration damping effect of Polymer concrete. Ti powder was added at a constant ratio in order to maximize the vibration damping effect using the piezoelectric effect. Three types of composite material specimens were prepared: a specimen without PZT powder, specimens with 2.5 wt% and 5 wt% of PZT powder. The vibration characteristics and compression properties were analyzed for all specimens. As a result, it was confirmed that as the addition ratio of PZT powder increased, the Inertance value at the resonant frequency decreased due to the piezoelectric effect when the vibration generated from Ti powder/polymer concrete was transmitted. Especially, the Inertance value was decreased by about 19.3% compared to the specimen without PZT at the resonant frequency. The change in acceleration with time also significantly decreased as PZT powder was added, confirming the effect of PZT addition. In addition, through the compression strength test, it was found that the degree of deterioration in compression properties due to the addition of PZT up to 5 wt% was insignificant, and it was confirmed that the powder was evenly dispersed in the composites through the cross-sectional analysis of the specimen.

Textural and geochemical characteristics of Fe-Mn crusts from four seamounts near the Marshall Islands, western Pacific

Jonguk Kim,Kiseong Hyeong,Chan Min Yoo,Jai-Woon Moon,Ki-Hyune Kim,Young-Tak Ko,Insung Lee 한국지질과학협의회 2005 Geosciences Journal Vol.9 No.4

Textural and geochemical properties of ferroman-ganese crust (Fe-Mn crust) samples from four adjacent seamountsnear the Marshall Islands were investigated to delineate the pale-oceanographic condition on their growth history. The Fe-Mn crustsamples of this study show four distinct layers (layers 1 to 4 fromtop to bottom). The uppermost layer 1 is massive and black, andis enriched in hydrogenetic elements such as Mn, Co, Ni, and Mo.The next layer 2 is porous and filled with sediment. Detrital (Al,Rb, and Ti) and biogenic (Cu, Zn, and Ba) elements are enrichedin layer 2. The layers 3 and 4 are phosphatized layers which areimpregnated with carbonate fluorapatite (CFA), and thereforetheir primary mineralogy and geochemistry were not preserved.The property of layer 2 suggested that this layer had grown underthe condition of high biogenic and detrital flux. Such a conditionmay be met in the Inter-tropical Convergence Zone (ITCZ) wherethe northeast and southeast trade winds met. Considering thehave formed when these seamounts were beneath the ITCZ. On theother hand, layer 1 may have started to grow after the seamountsmoved out of the ITCZ with the northwestward movement of thePacific plate. Our study indicates that the Fe-Mn crusts can beused to trace the paleolocation of ITCZ when precise age determi-nation and information on the plate movement are provided.

Prediction of transverse settlement trough considering the combined effects of excavation and groundwater depression

Kim, Jonguk,Kim, Jungjoo,Lee, Jaekook,Yoo, Hankyu Techno-Press 2018 Geomechanics & engineering Vol.15 No.3

There are two primary causes of the ground movement due to tunnelling in urban areas; firstly the lost ground and secondly the groundwater depression during construction. The groundwater depression was usually not considered as a cause of settlement in previous research works. The main purpose of this study is to analyze the combined effect of these two phenomena on the transverse settlement trough. Centrifuge model tests and numerical analysis were primarily selected as the methodology. The characteristics of settlement trough were analyzed by performing centrifuge model tests where acceleration reached up to 80g condition. Two different types of tunnel models of 180 mm diameter were prepared in order to match the prototype of a large tunnel of 14.4 m diameter. A volume loss model was made to simulate the excavation procedure at different volume loss and a drainage tunnel model was made to simulate the reduction in pore pressure distribution. Numerical analysis was performed using FLAC 2D program in order to analyze the effects of various groundwater depression values on the settlement trough. Unconfined fluid flow condition was selected to develop the phreatic surface and groundwater level on the surface. The settlement troughs obtained in the results were investigated according to the combined effect of excavation and groundwater depression. Subsequently, a new curve is suggested to consider elastic settlement in the modified Gaussian curve. The results show that the effects of groundwater depression are considerable as the settlement trough gets deeper and wider compared to the trough obtained only due to excavation. The relationships of maximum settlement and infection point with the reduced pore pressure at tunnel centerline are also suggested.

Effects of Less than 60 Days Delay in Surgery on Tumor Progression and Survival Outcomes in Invasive Breast Cancer Patients

Jonguk Lee,손병호,Saebyul Lee,Jong Won Lee,Beom Seok Ko,Hee Jeong Kim,Jisun Kim,Il Yong Chung,Guiyun Sohn,Sei Hyun Ahn 한국유방암학회 2016 Journal of Breast Disease Vol.4 No.2

Purpose: The effect of delays in surgical treatment on survival outcomes in patients with breast cancer remains uncertain, but it is an issue of importance to both patients and clinicians. The purpose of this study was to determine the impact of delayed surgical treatment on survival and tumor progression such as changes in tumor size and lymph node metastasis. Methods: Among 1,219 patients who underwent breast cancer surgery at Asan Medical Center between January 2008 and December 2008, 1,074 patients were finally included in the study following the application of inclusion and exclusion criteria. Patients were divided into two groups based on the interval between diagnosis and surgery: ≤30 days (group 1) and >30 days (group 2). We retrospectively analyzed clinical characteristics, changes in tumor size and axillary lymph-node status, and overall survival (OS) and disease-free survival (DFS) rates. Results: Between group 1 and group 2, there were no differences in clinical characteristics or in changes in tumor size between findings based on ultrasonography (USG) with biopsy at diagnosis and pathologic results (p=0.134). Furthermore, changes in tumor size and lymph-node status between USG results at Asan Medical Center and pathologic results also showed no differences (p=0.249 and p=0.233, respectively). There were also no significant differences in DFS (p=0.395) or OS (p=0.813). Conclusion: Our study showed that short-term delays of ≤2 months between diagnosis and surgery for breast cancer do not negatively affect cancer progression or survival rates.

Phosphorylation of the transcriptional repressor MYB15 by mitogen-activated protein kinase 6 is required for freezing tolerance in <i>Arabidopsis</i>

Kim, Sun Ho,Kim, Ho Soo,Bahk, Sunghwa,An, Jonguk,Yoo, Yeji,Kim, Jae-Yean,Chung, Woo Sik Oxford University Press 2017 Nucleic acids research Vol.45 No.11

<P><B>Abstract</B></P><P>The expression of <I>CBF</I> (C-repeat-binding factor) genes is required for freezing tolerance in <I>Arabidopsis thaliana. CBFs</I> are positively regulated by INDUCER OF CBF EXPRESSION1 (ICE1) and negatively regulated by MYB15. These transcription factors directly interact with specific elements in the <I>CBF</I> promoters. Mitogen-activated protein kinase (MAPK/MPK) cascades function upstream to regulate <I>CBFs</I>. However, the mechanism by which MPKs control <I>CBF</I> expression during cold stress signaling remains unknown. This study showed that the activity of MYB15, a transcriptional repressor of cold signaling, is regulated by MPK6-mediated phosphorylation. MYB15 specifically interacts with MPK6, and MPK6 phosphorylates MYB15 on Ser168. MPK6-induced phosphorylation reduced the affinity of MYB15 binding to the <I>CBF3</I> promoter and mutation of its phosphorylation site (MYB15<SUP>S168A</SUP>) enhanced the transcriptional repression of <I>CBF3</I> by MYB15. Furthermore, transgenic plants overexpressing MYB15<SUP>S168A</SUP> showed significantly reduced <I>CBF</I> transcript levels in response to cold stress, compared with plants overexpressing MYB15. The <I>MYB15<SUP>S168A</SUP></I>-overexpressing plants were also more sensitive to freezing than <I>MYB15</I>-overexpressing plants. These results suggest that MPK6-mediated regulation of MYB15 plays an important role in cold stress signaling in <I>Arabidopsis</I>.</P>

Sinking Particle Flux in the Subtropical Oligotrophic Northwestern Pacific from a Short-term Sediment Trap Experiment

Kim, Hyung Jeek,Kim, Jonguk,Kim, Dongseon,Chandler, Michael T.,Son, Seung Kyu Korean Ocean Research & Development Institute and 2018 OCEAN SCIENCE JOURNAL Vol.53 No.2

Time-series sediment traps were deployed in the subtropical oligotrophic northwestern Pacific (SONP) at three depths from August to September 2015 to better understand vertical flux of sinking particles. Sinking particles were collected at 5-day intervals over the sediment trap deployment period. The average total mass flux at water depths of 400 m, 690 m, and 1,710 m was 9.1, 4.4, and <TEX>$4.1mg\;m^{-2}day^{-1}$</TEX>, respectively. <TEX>$CaCO_3$</TEX> materials constituted 50 to 70% of sinking particles while in comparison particulate organic carbon (POC) constituted up to 20%. A synchronous variation of total mass flux was observed at the three depths, indicating that calcite-dominated particles sank from 400 to 1,710 m within a 5-day period. POC flux at these water depths was 2.4, 0.38, and <TEX>$0.31mg\;m^{-2}day^{-1}$</TEX>, respectively. Our results indicate low transfer efficiencies of 16% from 400 to 690 m and 13% for the 400 to 1,710 m depth range. The estimated transfer efficiencies were significantly lower than those observed at the K2 station in the northwest Pacific subarctic gyre, presumably because of a prevalence of pico-cyanobacteria in the SONP. Because cyanobacteria have a semi-permeable proteinaceous shell, they are more readily remineralized by bacteria than are siliceous phytoplankton in the northwest Pacific subarctic gyre. Continued surface water warming and expansion of the SONP will likely have a profound impact on ocean acidification in the northwest Pacific, possibly affecting the transfer efficiency of sinking POC to the deep-sea.

Design and evaluation of an AI model for automated tail vein administrator in rodent models

Jonguk Kim,Sung Woo Song,Chan Ho Song,Hae Jun Jeong,Jae Bong Lee,Hee Eun Kim,Sung Gurl Park 한국실험동물학회 2022 한국실험동물학회 학술발표대회 논문집 Vol.2022 No.7

Complete mitochondrial genome of the hydrothermal vent ghost shrimpParaglypturus tonganus(Crustacea, Axiidea, Callianassidae)

Kim, Se-Joo,Kim, Jonguk,Ahn, Dong-Ha,Ju, Se-Jong,Min, Gi-Sik,Kim, Sanghee Informa UK (Taylor Francis) 2016 Mitochondrial DNA. Part A Vol.27 No.2