• Title/Summary/Keyword: Time Analysis

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Analysis of Heat Transfer Characteristics on Multi-layer Insulating Curtains Coated with Silica Aerogel (실리카 에어로겔이 흡착된 다겹보온커튼의 전열 특성 분석)

  • Jin, Byung-Ok;Kim, Hyung-Kweon;Ryou, Young-Sun;Lee, Tae-Seok;Kim, Young-Hwa;Oh, Sung-Sik;Kang, Geum-Choon
    • Journal of Bio-Environment Control
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    • v.28 no.3
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    • pp.273-278
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    • 2019
  • The multi-layer insulating curtains used in the experiment was produced in six combinations using non-woven fabric containing aerogel and compared and analyzed by measuring heat flux and heat perfusion rates due to weight, thickness and temperature changes. Using silica aerogel, which have recently been noted as new material insulation, this study tries to produce a new combination of multi-layer insulating curtains that can complement the shortcomings of the multi-layer insulating curtains currently in use and maintain and improve its warmth, and analyze the thermal properties. The heat flux means the amount of heat passing per unit time per unit area, and the higher the value, the more heat passing through the multi-layer insulating curtain, and it can be judged that the heat retention is low. The weight and thickness of multi-layer insulation curtains were found to be highly correlated with thermal insulation. In particular, insulation curtains combined with aerogel meltblown non-woven fabric had relatively higher thermal insulation than insulation curtains with the same number of insulation materials. However, the aerogel meltblown non-woven fabric is weak in light resistance and durability, and there is a problem that the production process and aerogel are scattering. In order to solve this problems, the combination of expanded aerogel non-woven fabric and hollow fiber non-woven fabric, which are relatively simple manufacturing processes and excellent warmth, are suitable for use in real farms.

Electroencephalographic Changes Induced by a Neurofeedback Training : A Preliminary Study in Primary Insomniac Patients (뉴로피드백 훈련에 의한 뇌파 변화 연구 : 일차성 불면증 환자에 대한 예비 연구)

  • Lee, Jin Han;Shin, Hong-Beom;Kim, Jong Won;Suh, Ho-Suk;Lee, Young Jin
    • Sleep Medicine and Psychophysiology
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    • v.26 no.1
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    • pp.44-48
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    • 2019
  • Objectives: Insomnia is one of the most prevalent sleep disorders. Recent studies suggest that cognitive and physical arousal play an important role in the generation of primary insomnia. Studies have also shown that information processing disorders due to cortical hyperactivity might interfere with normal sleep onset and sleep continuity. Therefore, focusing on central nervous system arousal and normalizing the information process have become current topics of interest. It has been well known that neurofeedback can reduce the brain hyperarousal by modulating patients' brain waves during a sequence of behavior therapy. The purpose of this study was to investigate effects of neurofeedback therapy on electroencephalography (EEG) characteristics in patients with primary insomnia. Methods: Thirteen subjects who met the criteria for an insomnia diagnosis and 14 control subjects who were matched on sex and age were included. Neurofeedback and sham treatments were performed in a random order for 30 minutes, respectively. EEG spectral power analyses were performed to quantify effects of the neurofeedback therapy on brain wave forms. Results: In patients with primary insomnia, relative spectral theta and sigma power during a therapeutic neurofeedback session were significantly lower than during a sham session ($13.9{\pm}2.6$ vs. $12.2{\pm}3.8$ and $3.6{\pm}0.9$ vs. $3.2{\pm}1.0$ in %, respectively; p < 0.05). There were no statistically significant changes in other EEG spectral bands. Conclusion: For the first time in Korea, EEG spectral power in the theta band was found to increase when a neurofeedback session was applied to patients with insomnia. This outcome might provide some insight into new interventions for improving sleep onset. However, the treatment response of insomniacs was not precisely evaluated due to limitations of the current pilot study, which requires follow-up studies with larger samples in the future.

Comparative Analysis on Antioxidant Activity in Various Human Skin Fibroblasts and Mesenchymal Stem Cells (사람의 피부 섬유아세포 및 중간엽 줄기세포에서 항산화 활성의 반응에 대한 비교 분석)

  • Kong, Ji-Weon;Park, Ryeok;Park, Joon-Woo;Lee, Joo-Yeong;Choi, Yeon-Joo;Moon, Sun-Ha;Kim, Hyeon-Ji;Jeon, Byeong-Gyun
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.2
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    • pp.394-406
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    • 2019
  • The cellular senescence may be due to damage by the reactive oxygen species (ROS). This study has compared the antioxidant activity in the human cell lines of various origins, including 10S and 50S-derived normal skin fibroblasts, and 10S bone marrow, dental tissue and adipose-derived adult stem cells. After being exposed to $H_2O_2$, half inhibitory concentration ($IC_{50}$) values by cytotoxicity assay was significantly (P<0.05) lower in 50S-derived skin fibroblasts, than in 10S-derived skin fibroblasts and various adult stem cell lines. The cell population doubling time (PDT) and the cell frequency with high senescence associated-${\beta}$-galactose activity were remarkably increased in 50S-derived fibroblasts exposed to 50 ppm $H_2O_2$ for 7 days, than those of 10S-derived fibroblasts and various adult stem cell lines. Further, the expression level of antioxidant-related genes, glutathione peroxidase (GPX) and catalase (CAT), was investigated in 10S and 50S-derived skin fibroblasts, and 10S-derived various adult stem cells by reverse transcription polymerase chain reaction (RT-PCR). The expression level of GPX was higher in most of cell lines, compared to CAT, and a significantly (P<0.05) higher expression level of GPX was observed in 10S-derived skin fibroblasts and adult stem cell lines, compared to 50S-derived skin fibroblasts. We concluded that old-aged skin fibroblasts seemed to be less resistant against ROS than young-aged skin fibroblasts and adult stem cells.

Interpretation of the Manufacturing Characteristics and the Mineral and Chemical Composition of Neolithic Pottery Excavated from the Jungsandong Site, Yeongjong Island, South Korea (영종도 중산동 신석기시대 토기의 광물 및 화학조성과 제작특성 해석)

  • Lee, Chan Hee;Kim, Ran Hee;Shin, Sook Chung
    • Korean Journal of Heritage: History & Science
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    • v.51 no.1
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    • pp.4-31
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    • 2018
  • The Neolithic pottery excavated from the Jungsandong site has been classified into four types of pottery (I: feldspar type, II: mica type, III: talc type and IV: asbestos type) according to their mineral composition. These four types of potteries generally appear to have undergone incomplete firing, while the level of oxidation in the type I pottery objects, which have a relatively higher clay content, was found to be particularly low. The type III objects, which have a high talc content, are judged to have been somewhat slow in removing carbon because they contain saponite belonging to the smectite group. Of the four types of pottery, type IV showed the highest redness and the most uniform characteristics, thus indicating a good level of oxidation. In particular, fixed carbide (C; 33.7 wt.%) with a thickness of about 1mm, and originating from organic substances, was detected inside the walls of the type I pottery, while the deep radial cracks in the outer surfaces of the pottery are thought to have been caused by repeated thermal shocks. Given that all of the pottery except for the type I artifacts are considered to be have been made for storage purposes, those containing talc and tremolite are easy to done liquid storing vessels based on an analysis of their material characteristics. As for the type II relics, which are composed of various minerals and exhibit poor physical properties, they seem to have been used for simple storage purposes. As domestic talc and asbestos mines were concentrated in the areas of Gyeonggi, Gangwon, Chungbuk, and Chungnam, it seems likely that talc and tremolite were produced as contiguous minerals. Considering the distance between the remains in Jungsandong and these mines and their geographical distribution, there is a possibility - albeit somewhat slight - that these mines were developed for the mining of various minerals. Although ultramafic rock masses - such as serpentine capable of generating talc and tremolite - have not been found in the Jungsandong area, limestone and biotite granite containing mica schist have been identified in the northwestern part of Yeongjong Island, indicating that small rock masses might have formed there in the past. Therefore, it is judged necessary to accumulate data on pottery containing talc and tremolite, other than the remains in Jungsandong, and to investigate the rocks and soils in the surrounding area with greater precision. The firing temperatures of the pottery found at the Jungsandong site were interpreted by analyzing the stability ranges of the mineral composition of each type. As a result, they have been estimated to range from 550 to $800^{\circ}C$ for the type I artifacts, and from 550 to $700^{\circ}C$ for the type I, II and IV artifacts. However, these temperatures are not the only factors to have affected their physical properties and firing temperature, and the types, particle sizes, and firing time of the clay should all be taken into consideration.

Validation of Stem-loop RT-qPCR Method on the Pharmacokinetic Analysis of siRNA Therapeutics (Stem-loop RT-qPCR 분석법을 이용한 siRNA 치료제의 생체시료 분석법 검증 및 약물 동태학적 분석)

  • Kim, Hye Jeong;Kim, Taek Min;Kim, Hong Joong;Jung, Hun Soon;Lee, Seung Ho
    • Journal of Life Science
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    • v.29 no.6
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    • pp.653-661
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    • 2019
  • The first small interfering RNA (siRNA) therapeutics have recently been approved by the Food and Drug Administration in the U.S., and the demand for a new RNA therapeutics bioanalysis method-which is essential for pharmacokinetics, including the absorption, distribution, metabolism, and excretion of siRNA therapeutics-is rapidly increasing. The stem-loop real-time qPCR (RT-qPCR) assay is a useful molecular technique for the identification and quantification of small RNA (e.g., micro RNA and siRNA) and can be applied for the bioanalysis of siRNA therapeutics. When the anti-HPV E6/E7 siRNA therapeutic was used in preclinical trials, the established stem-loop RT-qPCR assay was validated. The limit of detection was sensitive up to 10 fM and the lower limit of quantification up to 100 fM. In fact, the reliability of the established test method was further validated in three intra assays. Here, the correlation coefficient of $R^2$>0.99, the slope of -3.10 ~ -3.40, and the recovery rate within ${\pm}20%$ of the siRNA standard curve confirm its excellent robustness. Finally, the circulation profiles of siRNAs were demonstrated in rat serum, and the pharmacokinetic properties of the anti-HPV E6/E7 siRNA therapeutic were characterized using a stem-loop RT-qPCR assay. Therefore, the stemloop RT-qPCR assay enables accurate, precise, and sensitive siRNA duplex quantification and is suitable for the quantification of small RNA therapeutics using small volumes of biological samples.

A Case of Progressive FSGS and Chronic Kidney Disease in Congenital Chloride Diarrhea with SLC26A3 Mutation (선천성 염소성 설사를 가진 환아에서 국소 분절 사구체경화증이 발생하여 만성 신장병으로 발전한 사례)

  • Seo, Young-Jun;Cheong, Han Bin;An, Seok Min;Sin, Woo Cheol;Bae, Eun Joo;Yoon, Jong Hyung;Jeong, Hwal Rim;Lee, Hong Jin
    • Journal of The Korean Society of Inherited Metabolic disease
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    • v.18 no.3
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    • pp.87-94
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    • 2018
  • We present the case of long-term observation of a patient with chronic kidney disease (CKD) caused by advanced focal segmental glomerulosclerosis (FSGS) resulting from underlying congenital chloride diarrhea (CLD). A 20-year-old woman was admitted for prolonged proteinuria despite conservative treatment for CLD. She was diagnosed with CLD and started taking KCl salt supplementation from the time of birth. Mild proteinuria was first found at 12 years of age, which progressed to moderate proteinuria at 16 years of age. At 16 years of age, CKD stage 2 with FSGS was diagnosed based on the initial assessment of the glomerular filtration rate (GFR) and kidney histology. On admission, we re-assessed her renal function, histology and genetic analysis. GFR had deteriorated to CKD stage 4 and renal histology revealed an advanced FSGS combined with tubulointerstitial fibrosis. A homozygous mutation in the SLC26A3 gene (c.2063-1G>T) was found by diagnostic exome sequencing and may have been inherited from both parents. CLD patients can be more vulnerable to renal injury, which may also cause progression of renal failure. Therefore, even if there is an early diagnosis and adequate salt supplementation, close monitoring of renal function and tailored treatment should be emphasized for renal protection and favorable CLD prognosis.

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Numerical Analysis of the Grand Circulation Process of Mang-Bang Beach-Centered on the Shoreline Change from 2017. 4. 26 to 2018. 4. 20 (맹방해빈의 일 년에 걸친 대순환과정 수치해석 - 2017.4.26부터 2018.4.20까지의 해안선 변화를 중심으로)

  • Cho, Young Jin;Kim, In Ho;Cho, Yong Jun
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.31 no.3
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    • pp.101-114
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    • 2019
  • In this study, we carry out the numerical simulation to trace the yearly shoreline change of Mang-Bang beach, which is suffering from erosion problem. We obtain the basic equation (One Line Model for shoreline) for the numerical simulation by assuming that the amount of shoreline retreat or advance is balanced by the net influx of longshore and cross-shore sediment into the unit discretized shoreline segment. In doing so, the energy flux model for the longshore sediment transport rate is also evoked. For the case of cross sediment transport, the modified Bailard's model (1981) by Cho and Kim (2019) is utilized. At each time step of the numerical simulation, we adjust a closure depth according to pertinent wave conditions based on the Hallermeier's analytical model (1978) having its roots on the Shield's parameter. Numerical results show that from 2017.4.26 to 2017.10.15 during which swells are prevailing, a shoreline advances due to the sustained supply of cross-shore sediment. It is also shown that a shoreline temporarily retreats due to the erosion by the yearly highest waves sequentially occurring from mid-October to the end of October, and is followed by gradual recovery of shoreline as high waves subdue and swells prevail. It is worth mentioning that great yearly circulation of shoreline completes when a shoreline retreats due to the erosion by the higher waves occurring from mid-March to the end of March. The great yearly circulation of shoreline mentioned above can also be found in the measured locations of shoreline on 2017.4.5, 2017.9.7, 2017.11.7, 2018.3.14. However, numerically simulated amount of shoreline retreat or advance is more significant than the physically measured one, and it should be noted that these discrepancies become more substantial for the case of RUN II where a closure depth is sustained to be as in the most morphology models like the Genesis (Hanson and Kraus, 1989).

The Characteristics of Child and Adolescent Suicide Attempters Admitted to a University Hospital (일 대학병원에 자살 시도 후 입원한 소아청소년들의 특성)

  • Bang, Yeon-Sik;Lee, Jinhee;Min, Seongho;Ahn, Joung-Sook;Park, Ki-Chang;Kim, Min-Hyuk
    • Korean Journal of Psychosomatic Medicine
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    • v.26 no.2
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    • pp.135-144
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    • 2018
  • Objectives : The purpose of this study was to identify the differences of demographic and clinical characteristics between child-adolescents who received medical inpatient care and non-hospitalized adolescents after suicide attempts. Methods : The study included 35 child-adolescents who were hospitalized (Admission group) and 114 child-adolescents who were not hospitalized (Non-Admission group) as a result of a suicide attempt from 2009 to 2015. We compared sociodemographic, clinical, and suicide attempt-related characteristics through a chi-square test and logistic regression analysis to evaluate the differences between the two groups. Results : Child-adolescents of this study most commonly attempted suicide by poisoning, and for motivation of interpersonal problems. Admission group had significantly fewer attempts through injury by sharp objects (${\chi}^2=4.374$, p=0.037) and attempted suicide with a higher chance of actually dying when compared to Risk-Rescue Rating Scale (t=1.981, p=0.049). In addition, Admission group had relatively common motivation for academic problems (${\chi}^2=12.082$, p=0.001) and less motivation for interpersonal difficulties. (${\chi}^2=9.869$, p=0.002) Psychiatric diagnosis at the time of visiting the emergency department showed higher rates of depression in the admission group than Non-Admission group (${\chi}^2=8.649$, p=0.003). The results of logistic regression showed that depression affects hospitalization (OR=2.783, 95% CI 1.092-7.089, p=0.032). Conclusions : This study is meaningful in that it revealed the social and clinical characteristics of all child-adolescents who were hospitalized at a university hospital after attempting suicide. This study identified differences in motivation, methods, and psychiatric diagnosis of hospitalized adolescents and those who were not. Therefore, the results may help adolescent suicide attempters to get a discriminatory approach based on their admission.

Clozapine Administration Potentiate Platelet Activation in Patients with Schizophrenia : Retrospective Study (클로자핀을 투여한 조현병 환자에서 혈소판 활성 증가에 관한 후향적 연구)

  • Kim, Hyun-Ah;Lee, Jong Wook;Kim, Seung-Jun;Oh, Hong-Seok;Im, Woo Young;Kim, Ji-Woong
    • Korean Journal of Psychosomatic Medicine
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    • v.26 no.2
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    • pp.188-193
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    • 2018
  • Objectives : Clozapine is a widely prescribed antipsychotic drug for schizophrenia and is known to increase the risk of cardiovascular disease due to its metabolic side effects. However, little is known about the effect of clozapine on the platelet activation, another important factor in the development of cardiovascular disease. In this study, we tried to investigate the effect of clozapine on platelet activity in patients with schizophrenia by comparing the mean platelet component (MPC) values before and after the clozapine administration. Methods : A retrospective review of medical records of patients with schizophrenia, who newly started clozapine treatment from September 1st, 2003 to April 30th, 2007 at the Department of Psychiatry, Konyang University Hospital in Republic of Korea was performed. The final statistical analysis included 14 participants. Bayer ADVIA $120^{(R)}$ system was used to measure MPC. Results : Among the 14 participants, five subjects were males (28.60%), and ten subjects were females (71.40%). The mean age of participants was $37.50{\pm}11.64years$. Average of duration of illness was $91.00{\pm}93.96months$, with the mean dosage of clozapine taken by participants at the time of the last blood test was $337.50{\pm}109.52mg$. The mean MPC measurement before and after receiving clozapine was $26.12{\pm}2.22g/dL$ and $25.14{\pm}2.08g/dL$ respectively. Wilcoxon signed rank test showed that there was a statistically significant decrease in MPC levels after clozapine administration (V=16, p=0.024). Conclusions : Decreased MPC levels after clozapine administration implies that clozapine may increase platelet activation which could have an adverse effect on the occurrence of thromboembolic disease. Our findings also suggest that careful monitoring of the risk factors of cardiovascular diseases, such as platelets activity, is necessary when administering clozapine.

Arctic Climate Change for the Last Glacial Maximum Derived from PMIP2 Coupled Model Results (제2차 고기후 모델링 비교 프로그램 시뮬레이션 자료를 이용한 마지막 최대빙하기의 북극 기후변화 연구)

  • Kim, Seong-Joong;Woo, Eun-Jin
    • Journal of Climate Change Research
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    • v.1 no.1
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    • pp.31-50
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    • 2010
  • The Arctic climate change for the Last Glacial Maximum(LGM) occurred at 21,000 years ago (21ka) was investigated using simulation results of atmosphere-ocean coupled models from the second phase of the Paleoclimate Modelling Intercomparison Program(PMIP2). In the analysis, we used seven models, the NCAR CCSM of USA, ECHAM3-MPIOM of German Max-Planxk Institute, HadCM3M2 of UK Met Office, IPSL-CM4 of France Laplace Institute, CNRM-CM3 of France Meteorological Institute, MIROC3.2 of Japan CCSR at University of Tokyo, and FGOALS of China Institute of Atmospheric Physics. All the seven models reproduces the Arctic climate features found in the present climate at 0ka(pre-industrial time) in a reasonable degree in comparison to observations. During the LGM, the atmospheric $CO_2$ concentration and other greenhouse gases were reduced, the ice sheets were expanded over North America and northern Europe, the sea level was lowered by about 120m, and orbital parameters were slightly different. These boundary conditions were implemented to simulated LGM climate. With the implemented LGM conditions, the biggest temperature reduction by more than $24^{\circ}C$ is found over North America and northern Europe owing to ice albedo feedback and the change in lapse rate by high elevation. Besides, the expansion of ice sheets leads to the marked temperature reduction by more then $10^{\circ}C$ over the Arctic Ocean. The temperature reduction in northern winter is larger than in summer around the Arctic and the annual mean temperature is reduced by about $14^{\circ}C$. Compared to low mid-latitudes, the temperature reduction is much larger in high northern altitudes in the LGM. This results mirror the larger warming around the Artic in recent century. We could draw some information for the future under global warming from the knowledge of the LGM.