The PoN (Proof of Nonce) distributed consensus algorithm basically uses a non-competitive consensus method that can guarantee an equal opportunity for all nodes to participate in the block generation process, and this method was expected to resolve the first trilemma of the blockchain, called the decentralization problem. However, the decentralization performance of the PoN distributed consensus algorithm can be greatly affected by the network transaction transmission delay characteristics of the nodes composing the block chain system. In particular, in the consensus process, differences in network node performance may significantly affect the composition of the congress and committee on a first-come, first-served basis. Therefore, in this paper, we presented a problem by analyzing the decentralization performance of the PoN distributed consensus algorithm, and suggested a fairness control algorithm using a learning-based probabilistic acceptance rule to improve it. In addition, we verified the superiority of the proposed algorithm by conducting a numerical experiment, while considering the block chain systems composed of various heterogeneous characteristic systems with different network transmission delay.

In recent years, importance of blockchain systems has been grown after success of bitcoin. Distributed consensus algorithm is used to achieve an agreement, which means the same information is recorded in all nodes participating in blockchain network. Various algorithms were suggested to resolve blockchain trilemma, which refers conflict between decentralization, scalability, security. An algorithm based on Byzantine Agreement among Decentralized Agents (BADA) were designed for the same manner, and it used limited committee that enables an efficient consensus among considerable number of nodes. In addition, election of committee based on Proof-of-Nonce guarantees decentralization and security. In spite of such prominence, application of BADA in actual blockchain system requires further researches about performance and essential features affecting on the performance. However, performance assessment committed in real systems takes a long time and costs a great deal of budget. Based on this motivation, we designed and implemented a simulator for measuring performance of BADA. Specifically, we defined a simulation framework including three components named simulator Command Line Interface, transaction generator, BADA nodes. Furthermore, we carried out response surface analysis for revealing latent relationship between performance measure and design parameters. By using obtained response surface models, we could find an optimal configuration of design parameters for achieving a given desirable performance level.

Metformin (1,1-dimethylbiguanide hydrochloride), derived from French lilac (Galega officinalis), is a first-line anti-diabetic drug prescribed for patients with type 2 diabetes. However, the role of metformin in odontoblastic cell differentiation is still unclear. This study therefore undertook to examine the effect of metformin on regulating odontoblast differentiation in MDPC-23 mouse odontoblastic cells derived from mouse dental papilla cells. As compared to controls, metformin significantly accelerated the mineralization, significantly increased and accelerated the expressions of ALP and Col I mRNAs, and significantly increased the accelerated expressions of DSPP and DMP-1 mRNAs, during differentiation of MDPC-23 cells. There was no alteration in cell proliferation of MDPC-23 cells, on exposure to metformin. These results suggest that the effect of metformin on MDPC-23 mouse odontoblastic cells derived from mouse dental papilla cells, facilitates the odontoblast differentiation and mineralization, without altering the cell proliferation.

RAPD 마커를 이용하여 인삼 품종 및 육성계통의 유전적 다양성 및 유연관계를 분석한 결과는 다음과 같다. 1. 총 130개의 primer 중 polymorphism을 나타내는 70개의primer를 선발하였고, 그 중 재현성이 있으면서 polymorphism이 높은 25개의 primer를 선발하였다. 증폭된 DNA 단편의수는 189개이고, PCR 산물은 100 ~ 2,800 bp 범위로 증폭되었다. 2. 각 primer에 의해 증폭된 DNA 단편의 수는 3개 ~ 17개로 다양하였으며, primer 한 개당 평균 7.6개의 DNA 단편이증폭되었다. OPD19 primer를 이용한 유전분석 결과, 총 5개의 유전양상이 나타났는데, 약 500 ~ 1,300 bp의 증폭산물에서품종 및 계통 간 유전적 다형성을 나타냈다. 3. 선발된 primer별 대립인자는 최소 1.33에서 최대 2.00의 범위였고, 평균 1.709이었다. primer별 유전적 다양성은 OPD15가 가장 높았고, OPF2가 가장 낮은 값을 나타내었다. 본 연구에서 분석에 이용된 25개의 RAPD primer 중에서 D15, D19, B5, A19등은 인삼 품종과 계통에서 비교적 높은 수의 대립단편과 높은 유전적 다양성 값을 나타내는 primer였다. 4. 유사도 계수 0.98을 기준으로 24개의 품종 및 계통을 대상으로 군집분석을 수행한 결과, 미국에서 수집 육성된 G04116과 국내 품종인 천풍, 연풍 그리고 국내 육성 계통인 G04009, G04026, G04069, G04084는 그룹을 형성하지 않았고, 17개의 품종 및 계통은 2그룹으로 분류되었다. I 그룹에는 고풍, 금풍과 12계통(85%), II 그룹에 3계통(15%)이 포함되었다.

Background : Recently, there is a urgent demand for development of new varieties with enhanced resistance to various biotic/abiotic stresses. In order to develop ginseng varieties with such traits, systematic breeding program and comprehensive field studies are prerequisite. Methods and Results : ‘Jinwon' seeds were collected in 2003 from the farmer field of Pocheon. Physiological investigation and propagation were conducted from 2008 to 2010. It was given the name 'Eumseong No. 11 through the observed yield trial from 2011 to 2013 and local adaptability was carried out from 2014 to 2017. All phenotypes including agronomic characteristics, seed yield, and physiological response to biotic/abiotic stresses were investigated according to the ginseng GAP and UPOV guidelines. Red leaf and red berry at maturing stage were observed. The time of emergence, flowering and berry maturity of the ‘Jinwon’ were faster than those of ‘Chunpoong’. Stem length of ‘Jinwon’ was longer than that of ‘Chunpoong’, whereas stem diameter was thicker than that of ‘Chunpoong’. Main root length was similar but main root diameter is thicker than that of ‘Chunpoong’. The yield performance of this variety was 576 ㎏/10 a in local adaptability test for two years, which is 9% higher than that of ‘Chunpoong’. ‘Jinwon’ showed strong resistance at high temperatures. Conclusion : Our study demonstrated that ‘Jinwon’ is an ideal variety with heavier root weight and enhanced stress resistance and contribute will enhance biotic/abiotic stress resistance and increase the farmers' income.

Background: In Korea, 6-year-old ginseng root is economically more important than 4 or 5-year-old roots. In general, the root age is determined by counting the number of stem vestiges. However, this method does not accurately estimate ginseng root age. Methods and Results: In this study, the stem vestige counting method was used to survey a total of 18,395 fresh ginsengs cultured in 2014, and 2015, to determine the accuracy of this method. The proportion of 6-year-old roots, with more than four stem vestiges, was 46.1% in 2014. For the cultivar Chunpoong cultivated in Eumseong and Goesan countries in 2015, the proportion of more than four stem vestiges was 55.9%, and 43.5%, respectively. The proportion of more than four stem vestiges for the Gumpoong cultivated in Eumseong and Yangpyeong countries was 67.0%, and 35.1%, respectively, whereas that for the cultivar Yunpoong was 36.0% and 61.0%, respectively. Moreover, it was confirmed that differences in the levels of Rg1 will enable root age determination. Conclusions: Root age determination by the stem vestige test was found to differ depending on the environmental and cultivation conditions. To determine the age of ginseng roots, a comprehensive method, such as counting stem vestiges and evaluating differences in ginsenoside levels, should be applied.

Background : For cultivation of varieties of ginseng, the pure line selection method, which is to select the best among those cultivated in farms for pedigree breeding, replicated yield trials and regional adaptation trials before registering as a new variety, is widely used. Although there are 25 registered varieties of ginseng in Korea, the quality of ginseng is declining together with the amount of harvest being decreased by 15 - 20% due to the heat injuries and diseases from the warming & abnormal climate. Thus, the needs for development of disaster-resistant varieties with better chances of surviving through high temperature, salts and disease are increasing. Therefore, this study is to cultivate disaster-resistant varieties among those selected for their disaster tolerance and salt tolerance through regional adaptation trials. Methods and Results : As a result of examining the growth characteristics of the selected 2 - 5 year old varieties used in the study, among the 5-year old crops, Goryeo 4 and Eumseong 5 showed superior growth in both above and below aerial parts, and among the 4-year old crops, Eumseong 11 and Cheonryang showed superior growth while the growth in the below aerial parts were satisfactory in the order of Cheonryang > Eumseong 10 > Eumseong 11 > Eumseong 9. Among the 3-year old crops, the most superior growth in both above and below aerial parts was observed in Eumseong 14 with the weight of the below aerial part, root diameter and taproot length at 13.8 g, 11.8 ㎝ and 6.2 ㎝ respectively. Among the 2-year old crops, Eumseong 10 showed the most superior growth in both above and below aerial parts. Conclusion : Based on the above results, Goryeo 4 and Eumseong 5 among the 5-year old crops, Eumseong 11 among the 4-year old crops, Eumseong 14 among the 3-year old crops and Eumseon 10 among the 2-year old crops showed the most superior growth among the selected varieties. The growth characteristics of both above and below aerial parts in each year will continuously be monitored.

Background : This study aimed to investigate the effect of elevated temperature by climate change on growth and ginsenoside contents of Korean ginseng, which requires low temperature during growth period. Methods and Results : Yunpoong was transplanted in temperature gradient chamber (TGC) for high temperature treatment and then growth characteristics and ginsenoside contents were investigated by growth period. Stem length, petiole length, leaf length and leaf width were increased as the temperature was higher than Ambient Temperature (Amb), but stalk diameter was decreased and small petiole length, number of petiole and leaf were no significant difference. Root growth, whereas, including length diameter and weight were decreased as the temperature was higher than Amb. Compared with Amb, root length, diameter and weight were decreased by 19.6%, 22.4% and 41.5% at Amb+6, respectively. The higher the temperatures are associated with the more ginsenoside contents. Compared to Amb, total ginsenoside contents were increased by 68% and 78% at Amb+4℃ and Amb+6℃, respectively. Almost all contents of individual ginsenoside, with the exception of Rg1, made a significant difference. Conclusion : When temperatures rises during growth period, the growth of ginseng was decreased but, ginsenoside contents were increased.

Background: Cylindrocarpon destructans (Zins) Scholten is an important pathogenic fungus that causes ginseng root rot in many ginseng growing areas in China. Although C. destructans have been studied worldwide, research on its chemotaxis towards ginseng (Panax ginseng C. A. Meyer) root exudates in the rhizosphere remains limited.Methods and Results: In this study, we collected ginseng root exudates with three different polarities from three-year-old ginseng roots, and performed chemotaxis and spore germination assays to investigate the ability of these exudates to induce the response in C. destructans. The results showed that, compared with other conditions, when C. destructans cultivated at 20°C and a pH of 6 exhibited a strong positive chemotactic response toward 2 ㎎/ℓ aqueous phase, 20 ㎎/ℓ butanol phase, and 0.2 ㎎/ℓ petroleum ether from ginseng root exudates, the chemotactic moving indexes were 0.1581, 0.1638 and 0.1441, respectively. In addition, the spore germination rate with optimal chemotactic parameters were 48%, 53%, and 41% in the aqueous phase, butanol phase and petroleum ether groups, respectiviely, which were significantly higher than that in the control group (23%) (p < 0.05). The mycelial growth rate with optimal chemotactic parameters increased with culture time, and the maximum growth rates in the aqueous phase, butanol phase and petroleum ether groups were 0.425, 0.406 and 0.364 respectively, on the 4th day. The optimal chemotactic parameters were 39.73 ㎎/50 ㎎/ℓ , 48.93 ㎎/50 ㎎/ℓ , and 31.43 ㎎/50 ㎎/ℓ , in aqueous phase, butanol phase and petroleum ether respectively, from ginseng root exudates, compared with 5.5 ㎎/50 ㎎/ℓ , in the control group.Conclusions: The present study revealed that certain ginseng root exudates containing chemical attractants act as nutritional sources or signals for C. destructans and support its colonization of ginseng roots.

Background : Ginseng (Panax ginseng C. A. Meyer) is a precious herb plant belonging to Araliaceae family especially in Asia and it has been cultivated more than a thousand years as a traditional medicine. Due to their pharmacological efficacy, old ginseng plants are traded high price, however, there are no crucial criteria to determine the ginseng age. To prevent illegal transactions, we assessed the telomere of ginseng roots based on modifications of the assays reported previously. Methods and Results : It is known that telomere length of ginseng root is shorter upon organismal aging. In this study, to support the determination of ginseng age, we modified and investigated methods through telomere analysis. Firstly, we examined the southern blot analysis whether telomere length depends on ginseng age. Based on previous study, we measured telomerase activity that is correlate with age. Furthermore, telomeric DNA was quantified by fluorescence in situ hybridization (FISH) to corroborate telomere shortening. The older ginseng root was shown short telomere length to compare with younger ginseng roots. Also enzyme activity of telomerase and amount of telomeric DNA represented decrease patterns upon age. Conclusion : Taken together, it is help to determine the age of ginseng through various methods using telomere because the results shown to positive correlation between telomeric characteristics and age for ginseng.

Background : Both Panax ginseng Meyer and Panax quinquefolius are obligate shade-loving plants whose natural habitats are broadleaved forests of Eastern Asia and North America. Panax species are easily damaged by photoinhibition when they are exposed to high temperatures or insufficient shade. In this study, a cytohistological study of the leaf structures of two of the most well-known Panax species was performed to better understand the physiological processes that limit photosynthesis. Leaves of ginseng plants grown in soil and hydroponic culture were sectioned for analysis. Methods and Results : Leaf structures of both Panax species were observed using a light microscope, scanning electron microscope, and transmission electron microscope. The mesostructure of both P. ginseng and P. quinquefolius frequently had one layer of noncylindrical palisade cells and three or four layers of spongy parenchymal cells. P. quinquefolius contained a similar number of stomata in the abaxial leaf surface but more tightly appressed enlarged grana stacks than P. ginseng. The adaxial surface of the epidermis in P. quinquefolius showed cuticle ridges with a pattern similar to that of P. ginseng. Conclusion : The anatomical leaf structure of both P. ginseng and P. quinquefolius shows that they are typical shade-loving sciophytes. Slight differences in chloroplast structure suggests that the two different species can be authenticated using transmission electron microscopy images, and light-resistant cultivar breeding can be performed via controlling photosynthesis efficiency.

Background : This study was carried out to distribute superior cultivars to farmers by analyzing growth characteristics of ginseng and effectively set the target for breeding by investigating annual agronomic characteristics of ginseng. Methods and Results : As a plant materials, Chunpoong (CP), Yunpoong (YP), Gopoong(GP), Gumpoong (GU) and Sunun (SU) were transplanted in Eumseong (ES), Geumsan (GS) and Yeoncheon (YC) on March 2013. Cultivation and management were conducted on the basis of the standard guidelines. According to stem and petiole by region, YC represent the largest stem diameter, leaf length and petiole length of cultivars, followed by those in ES and those in GS. Leaf growth of cultivars was overall the best in YC. Although CP had long and narrow leaves in all regions, YP and SU had short and narrow leaves. Root weight of all cultivars was the best in YC, but there was no significant differences by them. Growth of CP, YP and GP was generally good in ES. Growth of cultivars was relatively even in GS, but it was poor compared to cultivars which were cultivated in ES and YC. Conclusion : There were considerable differences in root growth of cultivars. However, this results suggest that CP of 4-year-old is produced stably in some regions because it had a small coefficient of variation.

Background : Stable ginseng production is highly dependent on specific climate conditions. Recently, ginseng yield and quality are negatively affected by climate changes, particularly global warming. Thus, it is imperative to apply a new systematic cultivation method and to develop new varieties with enhanced heat resistance to cope with elevated temperatures. Up to date, ginseng breeding program has mainly focused on the quantity and process ability of red ginseng. New varieties with increased resistance to diverse abiotic stresses need to be developed. Methods and Results : In this study, 13 varieties and 100 germplasms were screened for resistance to heat stress. To measure heat resistance, seedlings were transplanted to a pot 3 times in threes. Two months later, the pot was placed in a temperature chamber at 46℃ for 1 hour, a critical condition that ginseng appears to stop cellular respiration. After waiting for 1 day, the pot was examined for survival rate and fluorescent reaction. Fluorescent reaction was tested according to Nedbal et al. (2000) and Park et al. (2010) and with an image fluorometer. After testing chlorophyll fluorescent reaction, Fm/Fo, Fv/Fm and Rfd were used as screening indices for high temperature resistance. It was found that the adequate values for Fm/Fo, Fv/Fm and Rfd were over 2.2, over 0.55 and over 0.8, respectively. Also, the degree of the above-ground damage is investigated in the 4-year old field. Under our heat stress conditions, susceptible varieties (Chunpoong) and germplasm lines showed drooping and wilting leaf phenotypes, whereas the leaves of a resistant line (named Eumseong 11) remained healthy. Eumseong 11 had the highest values with 2.3, 0.61 and 0.98 in fluorescent test. In addition, compared to the susceptible lines which were wilted in 4-year old field, no detrimental phenotypes were observed in Eumseong 11. Conclusion : ‘Eumseong11’ was selected as a superior line with increased resistance to heat stress. We are now testing how Eumseong11 responds to other abiotic stresses. Our effort will contribute to increase the farmers' income.

Background : Panax ginseng C. A. Meyer is a slow-growing perennial herb that is cultivated in shading condition. Climate change occur around the world that make a lot of problem such as damage of high temperature, drought, salinity and disease. The problems lower the ginseng productivity that cause income reduction of farmers. To achieve stable ginseng production, development of elite varieities resistant to abiotic and biotic stresses is consistently required. It is very time consuming process in order to develop new ginseng varieties because ginseng flowers after 3 years of growth. So, early selection system of elite line must be established. This study was conducted to develope efficient ginseng breeding techniques for early identification of heat or salinity resistance. Methods and Results : Ginseng petioles was soaked in mixed salts solution consisting of KNO3, KH2PO4, MgSO4․H2O in order to test resistant or susceptible salinity. The degree of resistance was quantified according to damage size. Also, ginseng lines transplanted in pot were treated 46℃ for 1 hour and then chlorophyll fluorescence reaction were measured in order to test resistant or susceptible high-temperature. The measured values such as Fm/Fo, Fv/Fm, Rfd were differentiated between resistant and susceptible line. Conclusion : Several lines showed that they are resistance to high temperature or salinity. The selected lines will be utilized for parents to develop new varieties.

Background : The P. ginseng breeding line G07006, was selected for salt tolerance through salinity screening of mature leaves at the NIHHS of the RDA in 2014-2016. However, it is difficult to maintain a genetically stable breeding line of cross-pollinating crop in the field. Therefore molecular marker required to identify and maintain breeding line G07006. Methods and Results : DNA was extracted following the CTAB DNA extraction protocol (Doyle and Doyle, 1987) with modifications. A pair-end (PE) library was constructed and sequenced using an Illumina MiSeq platform by Lab Genomics, Inc. (Seongnam, Korea). Approximately 4.0 Gb of sequencing data were obtained, and de novo assembled by a CLC genome assembler(v. beta 4.6, CLC Inc., Rarhus, Denmark). The complete chloroplast(CP) genome size is 156,356 bp, including two inverted repeats (IRs) of 52,060 bp, separated by the large single-copy (LSC 86,174 bp) and small single-copy (SSC 18,122 bp) regions. This CP genome encodes 114 unigenes (80 protein-coding genes, four rRNA genes, and 30 tRNA genes), in which 18 are duplicated in the IR regions. Conclusion : This complete chloroplast DNA sequence will provide conducive to discriminate line G070006 (salt-tolerant) and further enhancing genetic improvement program of this important medical plant.

Background: Developing new ginseng cultivars is a significant time-consuming process owing to the three years of growth required for ginseng to flower. To shorten the ginseng breeding process, it is necessary to establish rapid progression through each generation. In this study, we examined it was possible to rapidly break ginseng seed dormancy using gibberellic acid (GA3) treatment and alternating temperature. Methods and Results: Seeds were obtained from local variety. Seeds were treated with either GA3 at a concentration of 100 ㎎/ℓ, constant temperature (−2℃ and 2℃), alternating temperature (2℃ followed by −2℃, followed by 2℃) or a combination GA3 and temperature treatment. Following experimental treatment, seeds were sown into trays and placed in a greenhouse. Low germination rates were observed in seeds that did not receive GA3 treatment, which were similar following 2℃ and −2℃ constant temperature treatment. Germination rates increased in proportion to GA3 and more so when combined with alternating temperature treatment. In additon, stem and leaf lengths of the resulting ginseng plants were increased following GA3 treatment, although no synergistic effect was observed with alternating temperature treatment. Conclusions: These results suggest that a combination GA3 and alternating temperature treatment enhances ginseng seed germination, which can contribute to shortening the time required to progress through a single ginseng generation for breeding.

Background: This study aimed to investigate the flowering and fruits formation characteristics of Korean Panax ginseng varieties. The results will provide basic data for ginseng seed production and breeding program. Methods and Results: The characteristics investigated included flowering date, seed setting rate, seed type and seed production. The ginseng variety Chungsun had the earliest emergency and flowering dates, whereas Sunhyang showed late emergence and flowering dates. The emergence date of Chunpoong was not later than that of the other varieties, but the flowering date was delayed. The seed setting rate was 64.6%, 75.8%, 78.5% and 74.4% for three, four, five and six-year-old varieties, respectively. The ratio of double seed (RD) for Sunhyang and Chungsun were higher than those for the others, whereas the RD for Chunpoong was the lowest. Yunpoong and Sunone had many stems per plant and a high seed production rate. Seed production was 21.7, 67.7, 74.4 and 89.0㎏/ 10 a in three, four, five and six-year-old varieties, respectively. Conclusions: The emergence date ranged from April 15 to 25, and the flowering date was from May 10 to the 19 for the new ginseng varieties. The average seed multiplication of the ginseng varieties was about 8.5 and 21.1 times a year for varieties in which, seed-production occurs once a year for over four years and four times over six years, respectively.