• Title/Summary/Keyword: Natural Experiment

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Isolation and Identification of an Autophagy-inducing Compound from Raphani Semen

  • Gu, Ming-Yao;Kwon, Hak Cheol;Song, Min Ok;Ko, Hyeonseok;Cha, Jin-Wook;Lee, Won Jong;Yang, Hyun Ok
    • Natural Product Sciences
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    • v.19 no.3
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    • pp.242-250
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    • 2013
  • The autophagy-lysosomal pathway is an important protein degradation system, and its dysfunction has been implicated in a number of neurodegenerative diseases, including Parkinson's disease. Raphani Semen, one of the herbs of Yeoldahanso-tang (YH), has neuroprotective effects via the autophagy pathway. The activity-guided method was used to isolate and identify the components of Raphani Semen. In this experiment, the total extract of Raphani Semen was partitioned to n-butanol, methylene chloride, and water fractions. Flow cytometry data showed that only the water fraction showed autophagy-inducing activity in vitro. Compounds 1 and 2 were isolated from this water fraction by preparative HPLC separation. The structures of compounds 1 and 2 were identified as stachyose and raffinose, respectively, by the analysis of various spectral data ($^1H$ NMR, $^{13}C$ NMR, and MS) and comparisons with standard stachyose and raffinose. Of these two compounds, raffinose showed autophagy-inducing activity in PC12 cells through the mTOR pathway.

Mitigating the Urban Heat Island Phenomenon Using a Water-Retentive Artificial Turf System

  • Tebakari, Taichi;Maruyama, Tatsuya;Inui, Masahiro
    • Proceedings of the Korea Water Resources Association Conference
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    • 2010.05a
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    • pp.91-100
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    • 2010
  • To investigate the thermal properties of a water-retentive artificial turf system (W-ATS), we estimated hydrologic parameters including thermal conductivity, heat capacity, and surface albedo for both the W-ATS and natural grass. We used a model experiment to measure surface temperature and evaporation for both the W-ATS and natural grass. We found that the W-ATS had lower thermal conductivity than natural grass did, and it was difficult for the W-ATS to convey radiant heat to the ground. Compared to natural grass, the W-ATS also had lower heat capacity, which contributed to its larger variation in surface temperature: the W-ATS had higher surface temperatures during daytime and lower surface temperatures during nighttime. The albedo of the W-ATS was one-quarter that of natural grass, and reflected shortwave radiation from the W-ATS surface was lower than that from the surface of natural grass. These results indicate that the W-ATS caused the soil temperature to increase. Furthermore, evaporation from the W-ATS was one-quarter the value of evapotranspiration from natural grass.

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Nitrogen Removal using Zeolite at On-site Wastewater Treatment System (소규모 오수처리 시스템에서의 제올라이트에 의한 질소 제거)

  • 방천희;권순국
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.44 no.2
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    • pp.161-173
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    • 2002
  • Recently, absorbent biofilters, which are inexpensive and easy to manacle, have been supplied to the rural areas, but have limitations in removing the nutrients effectively. Accordingly, as an alternative plan. natural zeolites were arranged in front or at the rear of the absorbent biofilters, and their removal efficiency for nitrogen and, ultimately, their applicability to the on-site wastewater treatment system were studied. Furthermore, the same experiments were carried out on artificial zeolites, made from coal ashes at National Honam Agricultural Experiment Station, to compare natural zeolites with artificial ones. Treated wastewater through the Absorbent Biofilter showed 22.6% nitrogen removal efficiency, while 64.6% was attained when natural Zeolites were placed in front of the absorbent biofilters (Zeolite-Aerobic process). As an addition, phosphorus was also efficiently removed. On the other hand, Aerobic-Zeolite process, which arranged natural zeolites at the rear of the biofilters, did not have significantly higher nitrogen removal as compared to the treatment using only the absorbent biofilters. Furthermore, upon regeneration of the natural zeolite, the ion exchange rate was fecund to increase over 10% as compared to before regeneration. Our results show that natural zeolites, applied to the on-site wastewater treatment system through the Zeolite-Aerobic process, not only increase the removal efficiency of nutrients, but, by choosing the appropriate regeneration time, can also be cast-effective. Artificial zeolites, on the other hand, though more efficient in removing nutrients, cannot be regenerated and, therefore, are not cost-effective.

A study on Natural Disaster Prediction Using Multi-Class Decision Forest

  • Eom, Tae-Hyuk;Kim, Kyung-A
    • Korean Journal of Artificial Intelligence
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    • v.10 no.1
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    • pp.1-7
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    • 2022
  • In this paper, a study was conducted to predict natural disasters in Afghanistan based on machine learning. Natural disasters need to be prepared not only in Korea but also in other vulnerable countries. Every year in Afghanistan, natural disasters(snow, earthquake, drought, flood) cause property and casualties. We decided to conduct research on this phenomenon because we thought that the damage would be small if we were to prepare for it. The Azure Machine Learning Studio used in the study has the advantage of being more visible and easier to use than other Machine Learning tools. Decision Forest is a model for classifying into decision tree types. Decision forest enables intuitive analysis as a model that is easy to analyze results and presents key variables and separation criteria. Also, since it is a nonparametric model, it is free to assume (normality, independence, equal dispersion) required by the statistical model. Finally, linear/non-linear relationships can be searched considering interactions between variables. Therefore, the study used decision forest. The study found that overall accuracy was 89 percent and average accuracy was 97 percent. Although the results of the experiment showed a little high accuracy, items with low natural disaster frequency were less accurate due to lack of learning. By learning and complementing more data, overall accuracy can be improved, and damage can be reduced by predicting natural disasters.

Effects of Gargle Using Natural Substances on Oral Environment

  • Kyung Min Kim;Kyung Yae Hyun;Min Kyung Lee
    • Biomedical Science Letters
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    • v.29 no.2
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    • pp.75-80
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    • 2023
  • In this study, natural mouthwash was developed based on natural substances based on cinnamon and ginger, which are familiar to the public, to check the effectiveness of mouthwash and changes in microbial distribution. This study was conducted on 24 people who fully explained the purpose and method of the study and agreed to participate among those who visited D University from October 2021 to December 2021. The subject's oral cavity was examined and placed in three groups to have similar conditions, and after using mouthwash for a week, a survey, saliva test, breath measurement test, and PCR test were performed. As a result of the experiment, the amount of saliva after using natural mouthwash increased compared to the control group (P<0.05). In the comparison of bacteria, it was confirmed that Pg and Fn bacteria decreased after using natural mouthwash (Pg t=4.852, P=.002, Fn t=2.888, P=.023). Following this study, it is expected that research on the development and efficacy of natural mouthwash will be conducted through various clinical applications, which will be useful in real life and dental care institutions.

Dynamic Properties of Artificial Stone with Waste Porcelain according to the ratio of Blast Furnace Slag (고로슬래그 치환율에 따른 폐자기 인조석재의 역학적 특성)

  • Seol, Dong Keun;Lee, Sang Soo;Song, Ha Young
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2015.11a
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    • pp.15-16
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    • 2015
  • Natural stone causes environmental pollution when it is collected and processed. Also, it is hard to make consistent products. Therefore, this study focuses on the artificial stone with waste porcelain to replace natural stone. The flexural strength and compressive strength are lower according to the replacement ratio of blast furnace slag in the result of experiment.

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A Study on Dynamic Characteristics of Reed Valve in Hermetic Compressor (압축기 밸브의 동적 특성에 대한 연구)

  • 조성욱;박성근;김형석;임종윤
    • Journal of KSNVE
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    • v.3 no.2
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    • pp.163-167
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    • 1993
  • Suction and discharge valves of special type refrigerant compressor are designed by finite element method for effective valve design development procedure. It is well known that valve dynamic characteristics, for example, the natural frequencies and vibration modes, are necessary for the computer simulation of compressor valve dynamics, the analysis of flow patterns, noise, impact stresses and their propagation phenomena. This paper has analysed the natural frequencies and vibration modes for the first three orders under the given special boundary conditions and the experiments are conducted by laser holography. And also stress distribution is analysed and experiment by strain gage is followed.

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RELAP5 Analysis of a Condensation Experiment in an Inverted U-tube

  • Park, Chul-Jin;Lee, Sang-Yong
    • Proceedings of the Korean Nuclear Society Conference
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    • 1995.10a
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    • pp.383-388
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    • 1995
  • Two-phase transient phenomena in the noncondensable gas-filled closed loop was investigated numerically using the RELAP5/MOD3 version 3.1 computer code. The condensation heat transfer correlation for noncondensable gases was studied in detail. Two modes of the reflux condensation which can be characterized by countercurrent flow of steam and its condensed water and the oscillatory between reflux condensation and natural circulation were predicted well. However, the natural circulation mode which the condensed water carried over the U-bend concurrently with steam was failed to predict.

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Finding-out the Natural Frequency of the Axle Gearbox Suspension System of the High-speed Train (고속전철 액슬 기어박스 현가계의 고유 진동수 측정)

  • 최진욱;차수덕;김용기;이태화
    • Proceedings of the KSR Conference
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    • 2001.10a
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    • pp.163-170
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    • 2001
  • Axle Gearbox of the High Speed Train has rotational degree of freedom centered on the Axle Shaft Center Line, and constrained by the Reaction Arm connected to the Bogie Frame via Resilient Ring made of Rubber. This System is laid on the Power Train and can influence on the Power transmitted from Motor to Axle. The stiffeness of the Resilient Ring have to be selected for the Natural Frequency of this System do not overlap with the Teeth-mating Frequency. To confirm the Design Parameters, Calculation and Experiment were executed and compared.

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Screening of Korean medicinal plants for antitumor activity

  • Chang, Il-Moo;Woo, Won-Sick
    • Archives of Pharmacal Research
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    • v.3 no.2
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    • pp.75-78
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    • 1980
  • Potential antinumor activity of sixteen Korean medicinal plants was tested against leukemia SN 36, murine tomor model. Survival studies by measuring life span indicated that Morus alba (Moraceae), Verbascum phlomoides (Scrophulariaceae), Curcuma longa (Zingbieraceae), Torilis japonica (Umbelliferae), Bupleurum falcatum (Umbelliferae) and Codonopsis pilosula (Campanulaceae) exhibited significant antitumor activity with the dose-schedule employed in the experiment. Methanol (70%) extracts of Platycodon gradiflorum (Campanulaceae), Bupleurum longeradiatum (Umbelliferae) and Asiasarum sieboldii (Aristolochiaceae) showed rather potent toxicity.

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