• 한국가시화정보학회지
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• 제8권4호
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• pp.48-53
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• 2010

Water-uptake through roots, is an essential process of the water flow in plants. Its visualization is very useful for understanding sap flow dynamics at whole plant level. In this study, the tips of Arabidopsis' root hairs were excised and exposed to repeated dehydration and rehydration processes. The water-refilling through individual xylem vessels was visualized using the synchrotron X-ray micro-imaging technique. The high temporal resolution ($2\;{\mu}m$) and beam intensity of the X-ray source allowed to acquisition of consecutive X-ray images of the water-refilling process up to 10 frames/sec. Various flow patterns were observed and the ascending speed of the water-air interfaces was analyzed. The relation between the water-rising height and ascending speed was also analyzed. The present results would provide better alternative for investigating sap flows in roots.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.415.2-415.2
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• 2002

We investigated the absorption enhancing effect of BuOH extract of the root of Aralia elata (BERAE) in Caco-2 cell monolayers and rats. At the concentration of both 0.04% and 0.08% (w/v). BERAE decreased the transepithelial electrical resistance (TEER) values and increased the permeability of intact chondroitin sulfate (CS) and its digestion products as hydrophilic macromolecules in a dose dependent manner. We also evaluated the cytotoxicity of BERAE for the determination of a proper concentration as an absorption enhancer. (omitted)

• 한국약용작물학회지
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• 제20권6호
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• pp.479-486
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• 2012

The production of adventitious roots derived from root explant of Echinacea angustifolia and its secondary metabolite content were assessed in different types and levels of auxin. The induction of adventitious roots from root explant cultured in Murashige and Skoog solid medium supplemented with 1.0 mg/L indole -3-butyric acid (IBA) attained highest as 20.87 mg fresh weight and 3.07 mg dry weight per culture but root suspension culture at the same concentration of IBA enhanced biomass production as 3.07 g fresh weight and 0.38 g per culture after 4 weeks in culture. 3.0 mg/L ${\alpha}$-naphthalene acetic acid (NAA) treatment had similar effect on root biomass production as 3.07 g fresh weight and 0.38 g per culture with liquid suspension culture, whereas adventitious roots exposed to over 3.0-5.0 mg/L IBA or 5.0 mg/L NAA were less responsive by reducing the number of adventitious roots and/or changing root morphology such as short and thick. The content of secondary metabolites such as phenolic, flavonoids and total caffeic acid in adventitious roots cultured on MS medium supplemented with 1.0 mg/L IBA were attained highest as 27.20, 9.60. 10.67 mg/g dry weight, respectively. Overall, the best production of root biomass and secondary metabolites were given by 1.0 mg/L IBA.

• 생약학회지
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• 제34권2호통권133호
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• pp.179-184
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• 2003

We have investigated the effect of MeOH extract of the adventious root culture of Panax ginseng on hyperlipidemic rats induced by fat-rich diet. We also analyzed and compared the content ginsenoisdes of the cultured ginsengs by HPLC. After oral administration of the MeOH extract to hyperlipidemic rats for four weeks, the variables including body weight, cholesterol, HDL, LDL, and triglyceride levels in serum were measured. One of the cultured ginseng roots (CBN3) decreased cholesterol and LDL-cholesterol and increased HDL-cholesterol levels in serum. HPLC analysis demonstrated that CBN3 contains more $Rb_1$ and Rd ginsenosides than any other cultured ginsengs and cultivated ginseng. These results suggest that CBN3 with high contents of $Rb_1$ and Rd may be useful in lowering blood cholesterol.

• Natural Product Sciences
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• 제12권1호
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• pp.29-37
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• 2006

One hundred and twenty six Vietnamese traditional herbals belonging to 59 families were screened for their free radical (DPPH) scavenging activity and inhibitory effect on lipid peroxidation. Of these, MeOH extracts of seven plants, including Euphorbia thymifolia (leaf), Gnetum montanum (stem), Heterosmilax erythrantha (root), Morus alba (leaf), Syzygium formosum (leaf), Jussiaea repens (aerial parts), and Camellia sinensis (leaf), exhibited significant antioxidant activities. All of these herbs showed remarkable free radical scavenging activities with $IC_{50}$ values of 11.0, 14.5, 17.0, 13.6, 10.8, 7.7, and $8.5\;{\mu}g/ml$, respectively, and significant inhibitory effects on lipid peroxidation with 79.7, 83.8, 78.9, 82.5, 88.8, 88.0, and 96.2% inhibitions, respectively, at the concentration of $50\;{\mu}g/ml$.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2023년도 학술발표회
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• pp.37-37
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• 2023

There is currently a high-accuracy modern forecasting method that uses machine learning algorithms or artificial neural network models to forecast river water levels or flowrate. As a result, this study aims to develop a mathematical model based on artificial neural networks to effectively forecast river water levels upstream of Tranh Culvert in North Vietnam's Bac Hung Hai irrigation system. The mathematical model was thoroughly studied and evaluated by using hydrological data from six gauge stations over a period of twenty-two years between 2000 and 2022. Furthermore, the results of the developed model were also compared to those of the long-short-term memory neural networks model. This study performs four predictions, with a forecast time ranging from 6 to 24 hours and a time step of 6 hours. To validate and test the model's performance, the Nash-Sutcliffe efficiency coefficient (NSE), mean absolute error, and root mean squared error were calculated. During the testing phase, the NSE of the model varies from 0.981 to 0.879, corresponding to forecast cases from one to four time steps ahead. The forecast results from the model are very reasonable, indicating that the model performed excellently. Therefore, the proposed model can be used to forecast water levels in North Vietnam's irrigation system or rivers impacted by tides.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2019년도 학술발표회
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• pp.154-154
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• 2019

Characterization of reliable field-scale root-zone soil moisture (RZSM) variability contribute to effective hydro-meterological monitoring. Although a promising cosmic-ray neutron probe (CRNP) holds the pontential for field-scale RZSM measurement, it is often restricted at deeper depths due to the non-unique sensitivity of CRNP-measured fast neutron signal to other hydrogen pools. In this study, a merging framework relied on coupling cosmic-ray soil moisture with a representative additional RZSM, was introduced to scale shallower CRNP effective depth to represent root-zone layer. We tested our proposed framework over a densely vegetated region in South Korea covering a network of one CRNP and nine in-situ point measurements. In particular, cosmic-ray soil moisture and ancillary RZSM retrieved from the most time stable location were considered as input datasets; whereas the remaining point locations were used to generate a reference RZSM product. The errors between these two input datasets and the reference were forecasted by a linear autoregressive model. A linear combination of forecasts was then employed to compute a suitable weight for merging two input products from the predicted errors. The performance of merging framework was evaluated against reference RZSM in comparison to the two original products and a commonly used exponential filter technique. The results of this study showed that merging framework outperformed other products, demonstrating its robustness in improving field-scale RZSM. Moreover, a strong relationship between the quality of input data and the performance merging framework in light of CRNP effective depth variation has been also underlined via the merging framework.

• 한국식품저장유통학회지
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• 제18권5호
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• pp.739-745
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• 2011

실험에서는 구절초를 꽃, 잎 줄기, 뿌리 등의 부위별로 구분하여 메탄올로 추출하고 추출 수율, 총 폴리페놀 및 총 플라보노이드 함량, DPPH radical 소거능, ABTS radical 소거능, superoxide anion radical 소거능, 아질산염소거능, 철 이온에 대한 킬레이트 효과, 환원력 등을 측정하였다. 추출 수율은 꽃이 가장 높았고 총 폴리페놀 함량은 꽃에서 가장 높게 나타났고 뿌리에서 가장 낮게 나타났다. DPPH radical 소거능과 ABTS radical 소거능은 추출물의 농도가 증가함에 따라 증가하였고 꽃과 잎 줄기가 뿌리보다 높은 소거능을 나타내었다. Superoxide anion radical 소거활성도 추출물의 농도 증가에 따라 증가하여 꽃 부위가 가장 높게 나타났으나 DPPH나 ABTS radical 소거활성보다는 다소 낮은 수치를 보였다. 철 이온에 대한 킬레이트 효과는 추출물의 농도가 증가함에 따라 증가하였고 꽃에서 가장 높게 나타났고 뿌리에서 가장 낮게 나타났다. 환원력은 꽃과 잎 줄기에서 높게 나타났고 뿌리에서 낮게 나타났다. 이상의 결과를 종합하여 보면 총 폴리페놀 함량이 가장 높은 구절초 꽃이 높은 항산화활성을 보였고 그 다음으로 잎 줄기가 활성을 보임으로써 향후 천연 항산화제로서의 개발 가능성이 시시되었다.

• 대한수학회보
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• 제53권4호
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• pp.1185-1196
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• 2016

We show a class of homogeneous polynomials of Fermat-Waring type such that for a polynomial P of this class, if $P(f_1,{\ldots},f_{N+1})=P(g_1,{\ldots},g_{N+1})$, where $f_1,{\ldots},f_{N+1}$; $g_1,{\ldots},g_{N+1}$ are two families of linearly independent entire functions, then $f_i=cg_i$, $i=1,2,{\ldots},N+1$, where c is a root of unity. As a consequence, we prove that if X is a hypersurface defined by a homogeneous polynomial in this class, then X is a unique range set for linearly non-degenerate non-Archimedean holomorphic curves.

• Restorative Dentistry and Endodontics
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• 제11권1호
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• pp.7-10
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• 1985

Coccal form of microorganism (staphylococcus) isolated from infected root canal was inoculated on the thioglycolate agar and paper discs (5mm in diameter) immersed with 0.1ml of 10% Formaldehyde, Thymol, Eugenol Phenol (90%) and 5% Silver nitrate were placed on the media. The thioglycolate plate was incubated at $37^{\circ}C$ for 48 hours. Inhibition zone was measured as follow: The greatest value was 3.9mm at Formaldehyde, next followed Thymol 3.6mm, Eugenol 3.5mm and Phenol 3.4mm. The least value, 3.0mm was found at Silver nitrate.