• 한국자원식물학회지
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• 제30권3호
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• pp.311-317
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• 2017

This study was conducted with the aim of evaluating the antibiotic effects of leaves, stems, and roots in yacon (Smallanthus sonchifolius). Antibacterial activity of leaf extract by disk diffusion method with Bacillus subtilis and Escherichia coli respectively showed 13.3 and 13.75mm diameters of clear zone. There was no significant difference between the stems and leaves. The minimum inhibitory concentration of leaves' heating and agitation extraction showed a restrain of strain at 1mg/ml, but the stems and root extract did not appear. Yacon is a functional antibacterial material, and methanol extraction is more effective than water. This research was to investigate the growth stage of collection has the most effective antibacterial effects. It has collected yacon's leaves from June to October, which is an appropriate time for collection right before reaping. Yacon leaf has antibacterial effects on Bacillus subtilis, Escherichia coli, Enterococcus faecium, and Salmonella enteritifis. There were no significant differences by the growth stage of collection. Leaves collected in July are high in phenol which helps in sulfating activity works well considering the high scavenging capability of DPPH. Leaves collected in September are high in total flavonoid.

• The Plant Pathology Journal
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• 제35권2호
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• pp.156-163
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• 2019

Our study investigated the available chlorine content, contact time and difference among strains of each pathogen for sodium hypochlorite (NaOCl) to control chemically against soil-borne fungal pathogens, such as Phytophthora rot by Phytophthora cactorum, violet root rot by Helicobasidium mompa, and white root rot by Rosellinia necatrix, causing die-back symptom on apple trees. As a result, the colony growth of Phytophthora cactorum was inhibited completely by soaking over 5 s in 31.25 ml/l available chlorine content of NaOCl. Those of H. mompa and R. necatrix were inhibited entirely by soaking over 160 s in 62.5 and 125 ml/l available chlorine content in NaOCl, respectively. Also, inhibition effect on available chlorine in NaOCl among strains of each soil-borne pathogen showed no significant difference and was similar to or better than that of fungicides.

• The Journal of Asian Finance, Economics and Business
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• 제8권2호
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• pp.453-463
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• 2021

Economic globalization provides a good channel for the development of foreign trade around the world. Due to this background, this paper sets the Organization for Economic Co-operation and Development (OECD) countries as a sample to explore the importance of international logistics in foreign trade. An annual panel data from 2000 to 2017 will be used to conduct an empirical estimation under the panel unit root test and the fixed effect model. Foreign trade is treated as an explained variable and international logistics is treated as explanatory variables. The findings show that international logistics have a positive spillover effect on export trade and the speed of international logistics development has a regulatory effect on the relationship between both of them, which presents a U-shaped curve. When the speed of international logistics development is slow, an increase of it restrains the positive spillover effect of international logistics on export trade. However, when it rises to a certain extent, this increase releases the positive spillover effect of international logistics on export trade. As can be seen by the evidence that this paper provides, the impact of international logistics on foreign trade is dynamic. Moreover, this paper also puts forward some corresponding measures about the relationship between both of them.

• Journal of Plant Biology
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• 제13권4호
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• pp.13-22
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• 1970

The rice variety, Kwanok, was reared in the water, land and salt seed beds and transplanted to the reclaimed soil area having an average of 0.48% salt content (0.67% at the end of April). The plant height of land bel seedlings at transplanting stage was short but the dry-weight/plant-height ratio was large and the rooting ability was vigorous remarkably after transplantation in the salty area. The central cylinder, vessels, sclerenchyma, endodermis and other mechanical tissues of the root of land bed seedlings were well developed while the size of cortical cell layers were small. The cytoplasm of the cortical parenchyma at the root tips seemed to be most abundant in the land bed seedlings. The formation of the aerial cavity in the cortex of primary root was rapid and it seemed that the developmental mechanism of the aerial cavity in the rice plant roots was related to the development of the lateral roots.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 춘계학술대회
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• pp.316-317
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• 1997

For successful endodontic therapy, complete and accurate biochemical and chemical preparations will allow accurate root canal. Hence the accurate determination of root length is very important for the highest rates of success in endodontic therapy. Among the apex locators, frequency dependent type has higher accuracy and more advantages than others. In this paper, we proposed better frequencies for the method of measuring root canal length by the ratio of two different impedances. It was found that 500Hz and 10kHz is better selection than other frequencies used in the commercial products.

• Journal of Ginseng Research
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• 제6권1호
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• pp.75-83
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• 1982

In this study it was found that the enzyme activities of diseased ginseng contributed greatly on the development of its root-rot disease. The 4i sensed ginseng showed higher activities of $\alpha$-amylase, p amylase, invertase, catalase, and cellulase than those of fresh one. The increased enzyme activities of diseased ginseng were originated in those from infected pathogens, which showed a proportional relationship between enzyme activities and root-rot power of them. The increases of enzyme activities during incubation of inoculated ginseng could be considerably depressed by controlling culture environments as to temperature below 4$^{\circ}C$, pH 8-9, and relative humidity about 60%, Some metal ions and organic reagents also inhibited the enzyme activities of diseased ginseng. But their inhibitory effects were not so great that they might be used to protect the disease.

• The Plant Pathology Journal
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• 제16권5호
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• pp.283-285
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• 2000

Two field tests were conducted in 1995 to examine the effects of composts and soil amendments on physicochemical properties of soil in relation to Phytophthora root and crown rot of bell pepper. Chitosan, crab shell waste, humate, sewage sludge-yard trimmings, and wood chips were applied to test plots, some of which affected the levels of P, K, Mg, pH, and H. Physicochemical properties were not related with disease incidence, but percent organic matter, estimated nitrogen release, K, and Mg were correlated with total microbial activity. The elements K and Mg were especially responsible for the increased soil microbial activity that could affect development of root and crown rot of pepper.

• 한국정밀공학회지
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• 제34권1호
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• pp.23-27
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• 2017

This paper aims to develop a prediction model for the product quality of a casting process. Prediction of the product quality utilizes an artificial neural network (ANN) in order to renovate the manufacturing technology of the root industry. Various aspects of the research on the prediction algorithm for the casting process using an ANN have been investigated. First, the key process parameters have been selected by means of a statistics analysis of the process data. Then, the optimal number of the layers and neurons in the ANN structure is established. Next, feed-forward back propagation and the Levenberg-Marquardt algorithm are selected to be used for training. Simulation of the predicted product quality shows that the prediction is accurate. Finally, the proposed method shows that use of the ANN can be an effective tool for predicting the results of the casting process.

• The Plant Pathology Journal
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• 제28권2호
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• pp.202-206
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• 2012

Root colonization by the rhizobacterium Pseudomonas chlororaphis O6 in Arabidopsis thaliana Col-0 plants resulted in induced tolerance to drought and salinity caused by halide salt-generated ionic stress but not by osmotic stress caused by sorbitol. Stomatal apertures decreased following root colonization by P. chlororaphis O6 in both wild-type and ABA-insensitive Arabidopsis mutant plants. These results suggest that an ABA-independent stomatal closure mechanism in the guard cells of P. chlororaphis O6-colonized plants could be a key phenotype for induced systemic tolerance to drought and salt stress.

• Plant Resources
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• 제2권2호
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• pp.65-68
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• 1999

This study was conducted to obtain the basic breeding information of Colocasia esculenta Schott. Effect of supplemental plant growth regulators and genotype difference were investigated on dormant bud tissue for proliferation. The plant regeneration ratio, plant height and root length were the best upon mixed treatment of 0.8mg/L IAA and 2.0mg/L zeatin. Both leaf weight and root weight were heavy upon culture in a dark condition. The leaf and root weights were heaviest in 6Pie sucrose concentrations. In several collected area the heaviest one was Binnangxin and then in the order of Suwon, Wanju and Puan. Genotype differences of tuber diameter and tuber weight were found in Suwon. Tuber weight was found in the order of Suwon (862mg) >Wanju(723mg) >Puan(649mg) >Binnangxin (424mg).