• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.340-345
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• 2006

A potato (Solanum tuberosum L. cv. Superior) cultivar was grown in aeroponic cultivation system to investigate the effect of root zone cooling in summer. Based on their nutrient uptake, growth responses, and tuberization, the possibilities for potato seed production were determined. Although shoot growth and early tuberization increased in the conventional non-cooling root zone system (root zone temperature of $25\pm2^{\circ}C$), stolen growth, photosynthesis, transpiration rate and number of tubers produced were higher in the cooling root zone system ($20\pm2^{\circ}C$) than in the non-cooling system. Increasing root zone temperature above $25^{\circ}C$ stimulated absorption of K more than T-N, P, Ca, Fe and Mn. On the other hand, root zone temperatures in the range of $20^{\circ}C$ to $25^{\circ}C$ did not affect Mg contents. The lower uptake and supply to leaves of T-N, Fe and Mn at the high root zone temperature promoted early tuberization and advanced haulm senescence. The results stress the importance of keeping root zone temperature to as low as below 20, particularly in summer under temperate Bone.

• Plant Disease and Agriculture
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• v.5 no.2
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• pp.90-94
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• 1999

Effect of inoculum concentration inoculation method and plant age on development of clubroot disease of Chinese cabbage seedling were examined in growth chambers. Root galls were developed at the concentration of 105 resting spore or above per ml of incoulum and as the inoculum concentration became higher rate of development of root galls was faster. In the plants with root gall development fresh weight of above ground parts was reduced to 30-44% of that of healthy plants but root weight increased by 4-10 times. Growth of diseased plants was greatly reduced as compared to healthy plants. Planting in the diseased soil as a inoculation method was most effective for disease development showing uniform infections but time of initial root gall development was delayed by root soaking inoculation. Some plants inoculated by soil drenching method did not develop root galls. However root gall enlargement after its initial formation did not differ greatly among inoculation methods. Nine-day-old seedlings showed poor development of root gall but 16-days-old seedlings was found to be most adequate for inoculation for gall development.

• Korean Journal of Medicinal Crop Science
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• v.22 no.1
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• pp.23-31
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• 2014

This study was carried out to investigate change of ginsenoside contents in red and fresh ginseng according to root part and age by hydrolysis. Neutral total ginsenoside contents by hydrolysis in 6-year main root and lateral root were significantly increased than those by non-hydrolysis, as 41.6 and 32.8%, respectively. However, there was no significant difference in red ginseng. In fresh ginseng, ginsenoside contents of the protopanaxatriol group such as Re, Rf, $Rg_1$, $Rg_2$, and $Rh_1$ were not significantly different, but $Rb_1$, $Rb_2$, $Rb_3$, Rc, and Rd showed significant difference. The increase rate of neutral total ginsenoside content by hydrolysis was higher in epidermis-cortex than stele. Also, the neutral total ginsenoside content was fine root > rhizome > lateral root > main root, respectively. While there was no tendency towards the increase of ginsenoside by hydrolysis with the increase of root age in fine root and rhizome, there was significant decrease in main root and lateral root.

• Journal of The Korean Society of Grassland and Forage Science
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• v.9 no.3
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• pp.135-140
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• 1989

This experiment was to study the relationship between shoot and root system in perennial ryegrass at different stages of growth. The results are summarized as follows; 1. The dry weight of shoot was significantly correlated with the dry weight of root at both stages of growth. 2. The yield components of shoot and root systems were changed by the stages of growth. Thus, the dry weights of shoot and root were positive correlated with the number of tillers and roots at 60 days after sowing. But, the dry weights of shoot and root were positive correlated with the dry weight of root, the dry weight of tiller, length of plant and length of root at 90 days after sowing. 3. Maprirna variety was obtained a higher dry weights of shoot and root at 60 days after sowing, but, Alta variety was obtained at 90 days after sowing, respectively. 4. The dry weight of shoot was positive correlated with leaf area at both stages of growth. 5. The dry weight of shoot was significantly negative correlated with specific leaf weight at 60 days after sowing, but positive correlated with specific leaf weight at 90 days afikr sowing. 6. The dry weight of root was smcantly positive correlated with leaf area at 60 days after sowing, but not recognized at 90 days after sowing.

• Korean journal of food and cookery science
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• v.24 no.4
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• pp.431-438
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• 2008

This study examined the quality characteristics of Sulgitteok samples prepared with different ratios of lotus root powder over 4 days of storage. The moisture contents of the lotus root powder-containing samples ranged from 35.39 to 37.31% and that of the Sulgitteok without lotus root powder control was 35.92%. The results showed that the various samples had the inconsistent changes during the storage period. As the content of lotus root powder increased, the L-values of samples decreased and the a- and b-values increased. However, their L-, a- and b-values did not show large differences with storage. When compared to the control, the hardness, gumminess, and chewiness of samples slowly increased as the amount of lotus root powder increased. Springiness and cohesiveness decreased according to the amount of added lotus root powder. And increasing amounts of lotus root powder and storage time resulted in greater reductions in adhesiveness. In addition, increasing storage time caused cohesiveness to decrease and springiness to increase. The sensory evaluation results showed that the 20% lotus root Sulgitteok received the highest scores, therefore, this samples was deemed superior.

• The Journal of the Korean dental association
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• v.40 no.7 s.398
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• pp.542-547
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• 2002

This study was aimed to help diagnose the vertical root fractures in endodontically and in nonendodontically treated teeth. This was a study about mine teeth with a vertical root fractures. Four cases were nonendodontically treated teeth and five cases were endodontically treated teeth. A collection of information including past dental history, periodontal probing, and X-ray was gathered on each case. One of the endodontic cases had no periodontal pocket depth and was in acute pain. It was confusing to find whether causes were because of endodontic failure or vertical root fractures. Most of the vertical root fractures were found in patients aged between 50 and 60. Vertical root fractures were found in the molar and premolar of maxillary and mandibular teeth. The second molars repecially, which had C shaped roots had vertical root fractures with apical propagation type. The apical propagation type means that vertical root fracture initiates in root apex and propagate to coronal root. The teeth with vertical root fractures of the apical propagation type, which was in acute pain, were very difficult in differential diagnosis of periodontal lesion and endodontic failure. Therefore, the dental history was very important to make a differential diagnosis. Past pain history repeated uncomfortable symptoms in bite was a key of differential diagnosis.

• Restorative Dentistry and Endodontics
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• v.38 no.2
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• pp.59-64
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• 2013

Apical surgery cuts off the apical root and the crown-to-root ratio becomes unfavorable. Crown-to-root ratio has been applied to periodontally compromised teeth. Apical root resection is a different matter from periodontal bone loss. The purpose of this paper is to review the validity of crown-to-root ratio in the apically resected teeth. Most roots have conical shape and the root surface area of coronal part is wider than apical part of the same length. Therefore loss of alveolar bone support from apical resection is much less than its linear length.The maximum stress from mastication concentrates on the cervical area and the minimum stress was found on the apical 1/3 area. Therefore apical root resection is not so harmful as periodontal bone loss. Osteotomy for apical resection reduces longitudinal width of the buccal bone and increases the risk of endo-perio communication which leads to failure. Endodontic microsurgery is able to realize 0 degree or shallow bevel and precise length of root resection, and minimize the longitudinal width of osteotomy. The crown-to-root ratio is not valid in evaluating the prosthodontic prognosis of the apically resected teeth. Accurate execution of endodontic microsurgery to preserve the buccal bone is essential to avoid endo-perio communication.

• The Korean Journal of Ecology
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• v.26 no.2
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• pp.59-64
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• 2003

We examined the effects of fertilization [control (C), 200 kg N ha^{-1} + 25 kg P ha^{-1}$ (LNP), and 400 kg N $ha^{-1} + 50 kg P ha^{-1}$ (HNP)] on fine root (＜ 2 mm diameter) dynamics using monthly soil coring method in a 39-year-old Pinus rigida plantation of central Korea. The average fine root biomass (live + dead) (kg $ha^{-1}$ $\pm$ SE) during the first growing season for C, LNP, and HNP was 1301 $\pm$ 54, 1084 $\pm$ 47, and 1328 $\pm$ 22, respectively. The fine root production (kg $ha^{-1}$ $\pm$ SE) was 2394 $\pm$ 128 for C, 2048 $\pm$ 101 for LNP, and 2768 $\pm$ 150 for HNP, respectively. Over the same period, fertilization treatments had impact on N and P concentrations of live fine root. Nitrogen and P inputs (kg $ha^{-1}$ $yr^{-1}$) into the soil through fine root turnover for C, LNP, and HNP were 16.6 and 0.9, 17.2 and 0.9, and 24.1 and 1.6, respectively. There were no significant differences in fine root biomass and production during the first growing season after fertilization. However, fertilization increased fine root N and P concentrations, and in consequence resulted in increased N and P inputs into soil through fine root turnover.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.25 no.2
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• pp.375-387
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• 1995

The purpose of this study was to quantitatively evaluated experimental tooth root resorption for digital radiography. For this study, experimentally three root sites were used, and radiograms were taken with standardized apparatus. Digital imaging system were consisted of NEC PC-980l(computer), TRINITRON(monitor), SONY XC-711 CCD camera. The display monitor had a resolution of 512X512 pixels. The obtained results were as follows: 1. In the difference of the four X-ray film of the contrast correction, the contrast difference was one gray scale variation at mean value. 2. Viewing of the view box of the periapical radiographs, experimental tooth root resorption of the periapical area of the first premolar, middle of mesial surface of the first molar mesial root, middle of lingual surface of the first molar distal root were recognized by increased diameter. 3. On the analysis by histogram, the periapical area of the first premolar, the middle of mesial surface of the first molar mesial root were each recognized tooth root resorption of the 5,6,7 pixel, 2,4,5 pixel by increased diameter. 4. On the analysis by histogram, the middle of lingual surface of the first molar distal root was each recognized tooth root resorption of the none, 3,6 pixel by increased diameter.

• Journal of Plant Biology
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• v.28 no.2
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• pp.127-140
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• 1985

A comparative anatomy between the secondary xylem in the root and stem of Korean Betulaceae, including 5 genera and 6 species, was carried out in this study. Anatomical characteristics of the secondary xylem in the root and stem are as follows: Diameter of vessel and fiber is wider in the root than the stem, while the number of vessel and fiber per unit area is fewer in the root than the stem. The length of vessel element is longer in the stem than the root, whereas length of the fiber is longer in the root than the stem. Number of bar in the perforation plate is more in the stem than the root, and the angle of perforation plate is broader in the root than the stem. Number of ray per unit area is more in the root than the stem.