• BMB Reports
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• v.53 no.3
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• pp.160-165
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• 2020

The root meristem of Arabidopsis thaliana is protected by the root cap, the size of which is tightly regulated by the balance between the formative cell divisions and the dispersal of the outermost cells. We isolated an enhancer-tagged dominant mutant displaying the short and twisted root by the overexpression of ZINC-FINGER OF ARABIDOPSIS THALIANA1 (ZAT1) encoding an EAR motif-containing zinc-finger protein. The growth inhibition by ZAT1 was shared by ZAT4 and ZAT9, the ZAT1 homologues. The ZAT1 promoter was specifically active in the outermost cells of the root cap, in which ZAT1-GFP was localized when expressed by the ZAT1 promoter. The outermost cell-specific expression pattern of ZAT1 was not altered in the sombrero (smb) or smb bearskin1 (brn1) brn2 accumulating additional root-cap layers. In contrast, ZAT4-GFP and ZAT9-GFP fusion proteins were distributed to the inner root-cap cells in addition to the outermost cells where ZAT4 and ZAT9 promoters were active. Overexpression of ZAT1 induced the ectopic expression of PUTATIVE ASPARTIC PROTEASE3 involved in the programmed cell death. The EAR motif was essential for the growth inhibition by ZAT1. These results suggest that the three related ZATs might regulate the maturation of the outermost cells of the root cap.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.28 no.2
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• pp.435-459
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• 1998

In order to achieve a successful endodontic treatment, root canals must be obturated three-dimensionally without causing any damage to apical tissues. Accurate length determination of the root canal is critical in this case. For this reason, I've used the conventional periapical radiography, Digora/sup (R)/(digital imaging system) and Root ZX/sup (R)/(the frequency dependent type apex locator) to measure the length of the canal and compare it with the true length obtained by cutting the tooth in half and measuring the length between the occlusal surface and the apical foramen. From the information obtained by these measurements, I was able to evaluate the accuracy and clinical usefulness of each systems. whether the thickness of files used in endodontic therapy has any effect on the measuring systems was also evaluated in an effort to simplify the treatment planning phase of endodontic treatment. 29 canals of 29 sound premolars were measured with #15, #20, #25 files by 3 different dentists each using the periapical radiography. Digora/sup (R)/ and Root ZX/sup (R)/. The measurements were then compared with the true length. The results were as follows: 1. In comparing mean discrepancies between measurements obtained by using periapical radiography(mean error: -0.449±0.444 mm), Digora/sup (R)/(mean error: -0.417±0.415 mm) and Root ZX/sup (R)/(mean error: 0.123±0.458 mm) with true length. periapical radiography and Digora/sup (R)/ system had statistically significant differences(p<0.05) in most cases while Root ZX/sup (R)/ showed none(p>0.05). 2. By subtracting values obtained by using periapical radiography, Digora/sup (R)/ and Root ZX/sup (R)/ from the true length and making a distribution table of their absolute values. the following analysis was possible. In the case of periapical film. 140 out of 261<53.6％) were clinically acceptable satisfying the margin of error of less than 0.5 mm. 151 out of 261 (53,6％) were acceptable in the Digora/sup (R)/ system while Root ZX/sup (R)/ had 197 out of 261(75.5％) within the limits of 0.5mm margin of error. 3. In determining whether the thickness of files has any effect on measuring methoths, no statistically significant differences were found(p>0.05). 4. In comparing data obtained from these methods in order to evaluate the difference among measuring methods, there was no statistically significant difference between periapical radiography and Digora/sup (R)/ system(p>0.05), but there was statistically significant difference between Root ZX/sup (R)/ and periapical radiography(p<0.05). Also there was statistically significant difference between Root ZX/sup (R)/ and Digora/sup (R)/ system(p<0.05). In conclusion, Root ZX/sup (R)/ was more accurate when compared with the Digora/sup (R)/ system and periapical radiography and seems to be more effective clinically in determining root canal length. But Root ZX/sup (R)/ has its limits in determining root morphology and number of roots and its accuracy becomes questionable when apical foramen is open due to unknown reasons. Therefore the combined use of Root ZX/sup (R)/ and the periapical radiography are mandatory. Digora/sup (R)/ system seems to be more effective when periapical radiographs are needed in a short period of time because of its short processing time and less exposure.

• Korean Journal of Environmental Agriculture
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• v.21 no.1
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• pp.69-73
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• 2002

Lettuce (Lactuca sativa L.) plants were grown under hydroponic system to characterize the diurnal change of nitrate concentration and nitrate uptake rate and to examine the effect of short term cold treatment to rhizosphere on nitrate concentration and uptake rate in lettuce plant. The nitrate concentrations in midrib were two times higher than those in leaf. Nitrate concentration in the shoot reached to minimum (8.7 mg-N/GDW) at 14:00 and, thereafter, increased continuously until 23:00. During 11:00$\sim$17:00, nitrate uptake by lettuce plant was maximum (4.8 mg-N/GDW-Root/hr). Short term cold treatment reduced nitrate concentration in the shoot by 14$\sim$18%, and nitrate uptake rate by 50$\sim$55%, respectively. These results showed that short term cold treatment before harvest could be applied for the purpose of reduction of nitrate concentration in the leaf under hydroponic culture.

• The Journal of the Acoustical Society of Korea
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• v.38 no.4
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• pp.433-441
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• 2019

In this paper, a method of estimating speech parameters for ultrasonic Doppler signals reflected from the articulatory muscles using LSTM (Long Short Term Memory) RNN (Recurrent Neural Networks) was introduced and compared with the method using MLP (Multi-Layer Perceptrons). LSTM RNN were used to estimate the Fourier transform coefficients of speech signals from the ultrasonic Doppler signals. The log energy value of the Mel frequency band and the Fourier transform coefficients, which were extracted respectively from the ultrasonic Doppler signal and the speech signal, were used as the input and reference for training LSTM RNN. The performance of LSTM RNN and MLP was evaluated and compared by experiments using test data, and the RMSE (Root Mean Squared Error) was used as a measure. The RMSE of each experiment was 0.5810 and 0.7380, respectively. The difference was about 0.1570, so that it confirmed that the performance of the method using the LSTM RNN was better.

• Journal of Plant Biology
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• v.13 no.4
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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.

• Proceedings of the KACD Conference
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• 2003.11a
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• pp.600-600
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• 2003

I. Objectives Effective endodontic obturation must provide a complete, three-dimensional filling of the root canal system, preventing the communication of fluids between root canal and surrounding periapical tissues. The objective of this study was to compare the apical leakage with or without the use of dentin adhesive system. II. Materials and Methods Forth extracted human teeth with single canals were decoronated. Root canals were instrumented using GT rotary files and Profile .04 file up to #40, 1mm short of the apex. After each instrumentation, copious irrigation with 5.25% sodium hypochlorite solution and confirmation of apical patency were performed.(omitted)

• Natural Product Sciences
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• v.24 no.2
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• pp.103-108
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• 2018

The usage of wild ginseng (Panax ginseng C.A. Meyer) has been limited due to short supply and high price. Therefore, sufficient production as well as efficient extraction of mountain ginseng are required for the development as products. In this study, wild ginseng adventitious root cultures were prepared for efficient production with advantages of fast growth and stable production. Treatment of methyl jasmonate (MJ) to wild ginseng adventitious root cultures increased the extraction yield and antioxidative activity. Further investigation on effect of extraction conditions suggested the importance of ethanol concentration on antioxidative activity and extraction yield of MJ-treated wild ginseng adventitious root cultures. Optimized extraction condition of MJ-treated wild ginseng adventitious root cultures for maximum extraction yield and antioxidative activity was determined using response surface methodology with three-level-three-factor Box-Behnken design (BBD). Extraction of 1 g MJ-treated wild ginseng adventitious root culture with 30 ml of 9% ethanol at $30^{\circ}C$ produced 310.2 mg extract with 71.0% antioxidative activity at $100{\mu}g/ml$. Taken together, MJ-treated wild ginseng adventitious root culture is valuable source for wild ginseng usage and optimized extraction condition can be used for the development of functional products or folk remedies.

• Journal of the Korean Society of Safety
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• v.9 no.1
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• pp.3-8
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• 1994

This paper has described the analysis of the Stress Intensity Factor behaviour of a short crack Initiated from notch tip. The model for finite element analysis is a double edge notched specimen. The parameters used in this study are crack length and notch root curvature radius.

• The Journal of the Korean dental association
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• v.10 no.6
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• pp.333-334
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• 1972

Bolk's so-called retromolar was found on the distal part of the upper third molar of adult male. The molar has a single short root and a tooth crown with five Cusps.

• Journal of international Conference on Electrical Machines and Systems
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• v.3 no.2
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• pp.190-199
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• 2014

In the last years, fault problem in power electronics has been more and more investigated both from theoretical and practical point of view. The fault problem can cause equipment failure, data and economical losses. And the analyze system require to ensure fault problem and also rectify failures. The current errors on these faults are applied for identified type of faults. This paper presents technique to detection and identification faults in three-phase voltage source inverter (VSI) by using time-frequency distribution (TFD). TFD capable represent time frequency representation (TFR) in temporal and spectral information. Based on TFR, signal parameters are calculated such as instantaneous average current, instantaneous root mean square current, instantaneous fundamental root mean square current and, instantaneous total current waveform distortion. From on results, the detection of VSI faults could be determined based on characteristic of parameter estimation. And also concluded that the fault detection is capable of identifying the type of inverter fault and can reduce cost maintenance.