• Title/Summary/Keyword: crown formation

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Correlation Between the Microclimate and the Crown of Platanus orientalis and Ulmus davidiana (버즘나무(Platanus orientalis)와 느릅나무(Ulmus davidiana)의 수관부와 미기후간의 상호 관계)

  • Lee, Jae-yoon;Ki, Kyong-Seok
    • Korean Journal of Environment and Ecology
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    • v.30 no.4
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    • pp.793-799
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    • 2016
  • This study examined Platanus orientalis and Ulmus davidiana planted in downtown parks to identify the correlations among microclimatic factors such as temperature in the crown, air flow, and wind speed. For the field survey, measurements were taken at 1 hour intervals from 09:00 am to 06:00 pm in August. For the measurement of microclimatic factors, data on temperature, light intensity, air flow, and wind speed were collected using a quantum sensor (PAR Quantum Sensor SKP215), a precision thermometer (Pt1000-Sensor), and a combination anemometer (1467 G4 & HG4). The results of the analysis demonstrated that both Platanus orientalis and Ulmus davidiana, showed a greater cooling effect inside the crown as compared with the outside temperature. The cooling effect inside the crown was more evident with air flow and wind speed factors. With relation to wind, the inner temperature of the crown of Platanus orientalis decreased due to air flow while that of Ulmus davidiana decreased due to wind speed. With no wind, the average variation in temperature inside the crown was $-0.9^{\circ}C$ for Ulmus davidiana and $-0.958^{\circ}C$ for Platanus orientalis, indicating that Platanus orientalis was relatively more effective in lowering the temperature of the planting space than Ulmus davidiana. This study is significant because it shows that different tree species have different effects on the microclimate and that factors affecting the formation of the microclimate of trees may vary with species. Further studies on species other than broad leaf trees, such as evergreen trees and shrubs, are required in order to plan the distribution of landscaping trees that are effective in regulating the microclimate within urban green spaces.

INTENTIONAL REPLANTATION OF CROWN-ROOT FRACTURED TOOTH WITH OPEN APEX (의도적 재식술을 이용한 치관-치근 파절된 미성숙영구치의 치험례)

  • Ryu, Jung-A;Lee, Jae-Ho;Choi, Byung-Jai;Son, Heung-Kyu;Choi, Hyung-Jun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.31 no.2
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    • pp.267-272
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    • 2004
  • This case report describes an uncommon treatment method for crown-root fractured incisor with immature root. A 7-year-old girl was referred for treatment of crown-root fractured maxillary central incisor. The fracture line extended to 1/2 of the total tooth length with incomplete root formation. The prognosis of crown-root fracture is usually poor and extraction is usually undertaken. But, in the mixed dentition, extraction of maxillary permanent incisor results in many complications, such as resorption of alveolar bone, poor esthetics, pronunciation and mastication. Conservative therapy in the permanent dentition comprises of few treatment modalities; supragingival restoration, gingivectomy, orthodontic extraction of apical fragment, surgical extrusion of apical fragment with or without rotational replantation. However, in this case, these indications are not applicable, so intentional replantation with adhesive resin system is the treatment of choice. The tooth was followed-up for 12 months. Currently, there are no symptoms. Since this modality adopts the respective advantages of both intentional replantation and adhesive treatment, it might be the treatment of choice in cases of vertical crown-root fracture.

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A Facile Synthesis of p-Nitrophenyl Glycosides

  • Yoon, Shin-Sook;Kim, Dong-Sung;Nam Shin, Jeong E.
    • Bulletin of the Korean Chemical Society
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    • v.15 no.7
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    • pp.559-563
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    • 1994
  • Glycosylation of benzoylated glycosyl halides of glucose, galactose and mannose with potassium p-nitrophenoxide and 18-crown-6 complex in chloroform resulted in the stereospecific formation of 1,2-trans p-nitrophenyl glycopyranosides in good yields. The same reaction with benzylated mannopyranosyl chloride gave the ${\alpha}-and\;{\beta}-p-nitrophenyl$ mannopyranosides in 3 : 1 ratio. However, acetylated 2-azido-altropyranosyl chloride gave ${\beta}-p-nitrophenyl$ altropyranoside only.

Expression and Localization of Keap1 During Amelogenesis in the Developing Molar Germ of Rats

  • Kim, Sun-Hun;You, Yong-Ouk;Ko, Hyun-Mi;Kim, Hyun-Jin
    • International Journal of Oral Biology
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    • v.43 no.4
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    • pp.177-183
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    • 2018
  • The objective of this study was to examine the expression pattern of Kelch-like ECH-associated protein 1 (Keap1) in the maxillary $2^{nd}$ molar germs of rats. We used the maxillary $2^{nd}$ molar germs in rats' pup at postnatal day 3 (bell stage), 6 (crown formation stage) and 9 (root formation stage). The investigation on mRNA and protein levels were done using reverse transcription - polymerase chain reaction and western blot. Localization of Keap 1 in the maxillary $2^{nd}$ molar germs were revealed through immunofluorescence staining. Keap1 from the maxillary 2nd molar germs were mostly manifested on postnatal day 3 and dramatically decreased on postnatal day 6 and 9 at mRNA and protein levels, while amelogenin and ameloblastin increased during the development of maxillary 2nd molar germs. During immunofluorescence analysis, the strong immunoreactivity against Keap1 was detected in the apical side of ameloblasts at the presecretory and secretory stages. However, Keap1 expression was hardly observed in the ameloblasts at the maturation stage. These results shows that Keap1 is strongly expressed in the presecretory and secretory ameloblasts of amelogenesis, and suggest that Keap1 may be a crucial molecule for the regulatory mechanisms tasked with the formation of enamel layer.

Determination of Complex Formation Constant of Sodium-Selective Ionophores in Solvent Polymeric Membranes (용매 고분자막 상에 고정된 나트륨 이온선택성 물질의 착물형성상수 결정)

  • Kang, Tae Young;Kim, Sung Bae;Oh, Hyon Joon;Han, Sang Hyun;Cha, Geun Sig;Nam, Hakhyun
    • Analytical Science and Technology
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    • v.13 no.4
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    • pp.466-473
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    • 2000
  • The complex formation constants (${\beta}_{MLn}$) of potassium and various sodium-selective neutral carriers in solvent polymeric membranes have been determined using solvent polymeric membrane-based optodes and ion-selective electrodes (ISEs). Two different types of PVC-based membranes containing the H^+selective chromoionophore (ETH 5294) with and without a sodium ionophore (4-tert-bntylcalix[4]arenetetraacetic acid tetraethyl ester, ETH 2120, bis[(12-crown-4)methyl] dodecylmethylmalonate or monensin methyl ester) were prepared and their optical responses to either the changes in alkali metal cation (e.g., sodium and potassium) concentrations at a fixed pH (0.05 M Tris-HCl, pH 7.2) or varying pH at a fixed alkali metal cation concentration (0.1 M) were measured. The same type of membranes were also mounted in conventional electrode body and their potentiometric responses to varying pH at a fixed alkali metal cation concentration (0.1 M) were measured. The complex formation constants of the ligand could be calculated from the calibration plots of the relative absorbance vs. the activity ratios of cation and proton ($a_{M^+}/a_{H^+}$) and of the emf vs. pH. It was confirmed that the ratio values of the complex formation constants for the primary and interfering ions are closely related to the experimental selectivity coefficients of ISEs.

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A Study on Development of the Third Molar as an Aid in Age Determination (제 3 대구치 발육의 연령감정에서의 응용에 관한 연구)

  • 이주장;김종열
    • Journal of Oral Medicine and Pain
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    • v.10 no.1
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    • pp.53-62
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    • 1985
  • This study was undertaken to obtain the data for age determination following the calcification degree of the third molar in the point of forensic odontology. The orthopantomograms of 1399 male and 2517 female ranging from 7 to 22 years of age were studied. The developmental state of the third molar was divided into 12 stages following the calcification degree and the mean ages of stage was obtained and statistically analyzed. The results were as follows : 1. There was remarkable correlation between the development of the third molar and age. 2. There was no significant developmental difference between the right and left third molar. 3. The development of the third molar presents difference between the male and female in the crown formation stages, but it was retarded in female than male in the root formation stages. 4. At the age under 20 years, we can determine the age within the range of * 2 years by means of orthopantomogram.

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The Effect of Combustion Process by Intensifying the Air Flow in Combustion Chamber of D.I. Diesel Engine (직접분사식 디젤기관의 연소실내 공기유동강화가 연소과정에 미치는 영향)

  • Bang, Joong-Cheol
    • Transactions of the Korean Society of Automotive Engineers
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    • v.15 no.5
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    • pp.153-159
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    • 2007
  • The performance of a direct-injection type diesel engine often depends on the strength of air flow in the cylinder, shape of combustion chamber, the number of nozzle holes, etc. This is of course because the process of combustion in the cylinder was affected by the mixture formation process. In the present paper, high speed photography was employed to investigate the effectiveness of holes penetrated from the bottom of cavity wall to piston crown for some more useful utilization of air. The holes would function to improve mixing of fuel and air by the increase of air flow in the cylinder. The results obtained are summarized as follows, (1) Activated first of the combustion by shorten of ignition timing and rapid flame propagation (2) Raised the combustion peak pressure, more close to TDC the formation timing of peak pressure.

ROENTGENOGRAPHIC STUDIES ON THE DEVELOPMENT OF ROOTS OF MANDIBULAR SECOND MOLARS (하악제2대구치 치근 발육에 관한 X-선학적 연구)

  • Cho Jung Hyun
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.1 no.1
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    • pp.13-19
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    • 1971
  • The author has studied on 910 roentgenograms of lower second molars, which were taken by intraoral technic, and obtained the following results. 1. The development of crown of lower second molars was completed 8.25 years. 2. The formation of mesial and distal roots in full length on lower second molars was completed as follows: a. mesial roots 15. 07 years b. distal roots 15. 53 years 3. The formation of apical foramina of mesial and distal roots of lower second molars was closured as follows: a. apical foramen of mesial root 18.00 years b. apical foramen of distal root 18.79 years 4. As a general rule, the mesial roots were developed more earlier than distal roots.

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A Numerical Analysis of a Drop Impact on the Liquid Surface (액적의 액막 충돌에 대한 수치해석)

  • Lee, Sang-Hyuk;Hur, Nahm-Keon;Son, Gi-Hun
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.2568-2573
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    • 2008
  • A drop impact on the liquid film/pool generates several phenomena such as the drop floating, bouncing, formation of vortex ring, jetting, bubble entrapment and splashing. These phenomena depend on the impact velocity, the drop size, the drop properties and the liquid film/pool thickness. These parameters can be summarized by four main dimensionless parameters; Weber number, Ohnesorge number, Froude number and non-dimensional film/pool thickness. In the present study, the phenomena of the splashing and bubble entrapment due to the drop impact on the liquid film/pool were numerically investigated by using a Level Set method for the sharp interface tracking of two distinct phases. After the drop impact, the splashing phenomena with the crown formation and spreading were predicted. Under the specific conditions, the bubble entrapment at the base of the collapsing cavity due to the drop impact was also observed. The numerical results were compared to the available experimental data showing good agreements.

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Effective Combination of Agrobacterium tumefaciens Strains and Ti Plasmids for the Construction of Plant Vector System

  • Kim, Mi-Suk;Park, Jeong-Du;Eum, Jin-Seong;Sim, Woong-Seop
    • Journal of Plant Biology
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    • v.39 no.3
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    • pp.179-184
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    • 1996
  • The purpose of this study is to obtain the most efficient combination of Agrobacterium tumefaciens strains and Ti plasmids for the construction of dicotyledonous plant vector system. Ti plasmid-curing A. tumefaciens A136 and KU12C3 were transformed with four kinds of Ti plasmids, pTiBo542, pTiA6, pTiKU12 and pTiAch5, respectively. The stems of 28 species of dicotyledonous plants were then inoculated with these transformants and examined for crown gall formation. The different combination of A. tumefaciens strains and Ti plasmids showed quite a difference in terms of the crown gall formation. Agrobacterium strins A136 and KU12C3 have a same plant host range in case that both strains harour the same kind of Ti plasmid, pTiBo542 or pTiAch5. However, the above-mentioned both strains have quite different host range in the event of containing the same Ti plasmid, pTiKU12 or pTiA6. In case that KU12C3 contains pTiA6 or pTiKU12, this strain has a wider plant host range than A136. The plant host range of pTiBo542 is the widest, followed by pTiA6, pTiKU12 and pTiAch5. Twelve plants among 28 tested plants are not transformed by any virulent Agrobacterium strains used in this study. In conclusion, A. tumefaciens KU12C3 and A136 harboring pTiBo542 showed the widest host range for transforming dicotyledonous plants. Also, it was acertained that the host range of Ti plasmids is affected by chromosomal level.

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