• The Korean Journal of Pharmacology
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• v.27 no.1
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• pp.53-67
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• 1991

The characteristics and differences between DMPP and McN-A-343 on the secretory effect of catecholamines(CA) were studied in the isolated perfused rat adrenal glands. DMPP(100 uM) and McN-A-343(100 uM) perfused into an adrenal vein of the gland casued significant increases in CA secretion. On molar basis the secretory effect of McN-A-343 was about one fifth as potent as that of DMPP. Tachyphylaxis to releasing effects of CA evoked by DMPP and McN-A-343 was not observed by repeated perfusion of these agents. The DMPP-evoked CA secretion was significantly inhibited by pretreatment with chlorisondamine, desipramine and profusion of $Ca^{2+}-free$ Krebs solution containing EGTA, while it was not affected by pirenzepine, ouabain and physostigmine. However, pretreatment with atropine rather enhanced CA release by DMPP. The releasing effect of CA induced by McN-A-343 was markedly depressed by pretreatment with atropine, pirenzepine, chlorisondamine, physostigmine, and perfusion of $Ca^{2+}-free$ medium plus EGTA but was not influenced by desipramine, except for the case of ouabain which clearly potentiated CA release by McN-A-343. These experimental results suggest that both DMPP and McN-A-343 cause greatly secretion of CA from the isolated perfused rat adrenal glands by a calcium-dependent exocytotic mechanism. The secretory effect of DMPP is due to the stimulation of cholinergic nicotinic receptors and the secretion by McN-A-343 via activation of selecive $M_{1}-muscarinic$ receptors in the adrenal gland. It is also thought that the DMPP-evoked secretory effect is much greater than McN-A-343-induced effect.

• Korean Journal of Medicinal Crop Science
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• v.12 no.1
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• pp.17-23
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• 2004

This study was carried out to obtain the basic information on mating parents and selection for high yielding safflower breeding. Thirty nine world safflower lines, which had collected from 13 countries of origjn, were evaluated for major agronomic characters, correlation and path-coefficients. The results obtained were summarized as follows. Days to flowers ranged from 83 days to 100 days. Days to flower of most foreign lines were later than that of domestic lines. Plant height ranged from 75 cm to 162 cm. The plant height and stem diameter of most foreign lines were higher than those of domestic lines. The leaf number and size of domestic lines were much more than those of foreign lines. The total branch numbers of foreign lines were more than domestic lines. Particularly, the number of third branch ranged from 0 to 25 and there were none in domestic lines. The number of corolla of foreign lines was much more than that of domestic lines. The yield of foreign lines collected from Central Asia and United States of America were more than any others. Significantly positive correlations were observed between yield and days to flower, stem diameter, the number of branch and the number of corolla. In the analysis of path-coefficient, the highest direct effects on yield was the number of corolla followed by the number of total branch, whereas those of the number of second branch and stem diameter were negative.

• Journal of the Institute of Convergence Signal Processing
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• v.15 no.4
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• pp.162-168
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• 2014

The OFDM system have been widely studied for the purpose of increasing data rate with more reliable communications in underwater channel environments. And it is possible only when the sub-carrier's bandwidth is smaller than the coherence bandwidth of channel in the underwater OFDM communication system. However, the size of the FFT for the OFDM system will be increased because the coherence bandwidth is as small as several tens of Hz in real underwater channel environments. Also, It is necessary to add a CP having a length longer than the rms delay spread of a channel. So the complexity of the system is increased and the data efficiency is reduced. Therefore, in this paper, we have studied the increase of the coherence bandwidth by adapting the beamforming technologies. To do this, we have collected data from real underwater channel environments and analyzed the coherence bandwidth when adapting the beamforming technologies. Analyzing the experimental data show that the coherence bandwidth by the beamforming technologies in underwater channel environments was greatly increased compared to that of a single sensor.

• The Journal of Korean Academy of Prosthodontics
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• v.34 no.4
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• pp.746-754
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• 1996

The purpose of this study was to evaluate the fracture strength of porcelain laminate veneer with various lingual extention length when incisal restoring. Sixty recently extracted, intact maxillary incisors were used and stored in a physiologic saline solution from the time of extraction. Seating form was preparation at the labial surface of each tooth with a water-cooled round diamond bur. Standard block was formed with 32 gauge and 24 gauge wax at tooth labial and lingual surface. Lingual extention length differed according to each group. (group I : 0.5mm, group II : 1 mm, group III : 2mm, group IV : 0mm) All tooth specimens were impressioned with examix(GC Inc., Japan). Refractory cast were maked with refractory die material(Ceramco Inc., U.S.A.) Laminate porcelain (Ceramco II Veneer porcelain, Ceramco Inc., U.S.A.) was condensed in refractory die cast and baked according to the manufacturer's recommendations. Each surface was contoured with low speed diamond bur according to guide block. All porcelain specimens were sandblasted and ultrasonically cleaned in distlled water for 3 minutes. Then, all porcelain specimen were etched with 8% hydrofluoric acid for 5 minutes. Sixty specimens were bonded with composite resin cement(Choice Porcelain Veneer System, Bisco Inc., U.S.A.) according to manufacture's directions. The fracture loads of the specimen were measured by Instron universal testing machine. The mean values of fracture loads for the groups were statistically compared by Duncan's multiful range test. The result were as follows : Mean fracture strengths of each group were 86.95Mpa in no lingual extention group, 44.98Mpa in 0.5mm lingual extention group, 27.47Mpa in 1mm lingual extention group, 19.61Mpa in 2mm lingual extention group. There was a statistically significant difference between all group(p<0.01).

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.4
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• pp.688-702
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• 1999

The purpose of this study was to investigate the revascularization and reinnervation of calcitonin gene-related peptide immunoreactive nerves in immediately replanted rat molars. First maxillary right molars in 56 rats(35days old) were extracted and immediately replanted. The rats were killed 1, 2, 3, 7, 14, 28 and 42 days after replantation and revascularization of pulpal blood vessels were examined microangiogram with korean traditional ink and reinnervation of pulpal nerve were examined immunohistochemical method using calcitonin gene-related peptide(CGRP) antiserum. The results were as follows; 1. Revascularization and reinnervation of CGRP immunoreactive nerve fibers were observed mesial side whole pulp tissue of replanted teeth. Revascularization and reinnervation of CGRP immunoreactive fiber were made at 2days after replantation in entire pulp of replanted teeth and the distribution density of blood vessels were gradually increased according time elapsed, but did not achieve the density of control. 2. Postoperative dentin formation in replanted teeth revealed at 1week after replantaton and gradually increased according to time elapsed. 3. Revascularization and Reinnervation of CGRP immunoreactive nerve fibers were established at the same time and it seems to be closed relatationship between revascularization and reinnervation.

• Journal of dental hygiene science
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• v.13 no.4
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• pp.461-470
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• 2013

In order to examine the anticariogenic effect after fluoride varnish was applied to sound enamel and artificial caries enamel, anterior teeth of healthy cattle were used and divided into four groups such as group 1 (sound enamel), group 2 (application of fluoride varnish to sound enamel), group 3 (artificial caries enamel) and group 4 (application of fluoride varnish to artificial caries enamel). Remineralization on the surface of enamel and changes of crystalline structure after demineralization were observed by using a field emission scanning electron microscope (FE-SEM). Quantitative analysis of Ca and P was measured by using the energy dispersive X-ray spectrophotometer (EDS). The following conclusions were obtained: 1)Surface pattern of enamel was the roughest in group 3 due to the defects caused by porosity and microcracks. Group 4, group 1 and group 2 were followed in order; 2) It was found that pattern of crystalline structures in a group of application of fluoride varnish and a group of no application showed bigger change in artificial caries enamel than that in sound enamel. In other words, groups 4 and 1 showed a similar pattern; 3) The contents of Ca and P were higher in groups of application of fluoride varnish (group 2 and group 4) than in groups of no application of fluoride varnish (group 1 and group 3). Taken results of this study together, in the case of application of fluoride varnish, crystalline structure was changed by remineralization even in the sound enamel. In particular, porous structures showed a smooth and uniform pattern due to the recalcification in the artificial caries enamel. In addition, according to results of EDS analysis, the contents of Ca and P were increased and it had great anticariogenic effects which inhibit decalcification of sound enamel and artificial caries enamel.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.10
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• pp.95-104
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• 2004

This paper propose a motion estimator architecture to reduce the power consumption of the most-power-consuming motion estimation method when designing multimedia SoC with deep submicron technologies below 0.13${\mu}{\textrm}{m}$. The proposed architecture considers both dynamic and static power consumption so that it is suitable for large leakage process technologies, while conventional architectures consider only dynamic power consumption. Consequently, it is suitable for mobile information terminals such as mobile videophone where efficient power management is essential. It exploits full search method for simple hardware implementation. It also exploits early break-off method to reduce dynamic power consumption. To reduce static power consumption, megablock shutdown method considering power line noise is also employed. To evaluate the proposed architecture when applied multimedia SoC, system-level control flow and low-power control algorithm are developed and the power consumption was calculated based on thor From the simulation results, power consumption was reduced to about 60%. Considering the line width reduction and increased leakage current due to heat dissipation in chip core, the proposed architecture shows steady power reduction while it goes worse in conventional architectures.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.25 no.2
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• pp.399-408
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• 1995

The purpose of this study was to obtain information on the clinical and radiographic features of the dentigerous cysts in the jaws. For this study, the authors examined and analysed the clinical records and radiographs of 233 patients who had lesions of dentigerous cyst diagnosed by clinical and radiographic or histopathological examinations. And the obtained results were as follows: 1. Dentigerous cysts occurred the most frequently in the 2nd decade(38.2％) and occurred more frequently in males(67.4％) than in females(32.6％). 2. The most common clinical symptom was swelling of the jaw(33.9％), and the lesions were treated by the method of surgical removal. 3. The type of lesions was mainly observed as central type(72.5％), and size of the lesion was most frequently observed 2 - 2.9cm in the widest length. 4. The lesions were most frequently observed well-defined outline with hyperostotic border(49.8％), and smooth margin(73.4％), and homogeneous lesional radiolucency(79.4％). 5. Cortical thinning and expansion of the lesions(82.0％) were observed, and their direction were most frequently observed toward buccal side(64.0％). 6. The effect on the causative tooth were observed as tooth displacement(41.2％) and delayed root development(l9.3％), and the distance between cemento-enamel junction and lesional wall attachment of the causative tooth was mainly observed as below 2mm(79.6％). 7. The effect on the adjacent tooth were observed as loss of lamina dura(66.8％), root resorption(33.9％), and tooth displacement(31.5％). 8. The effects on the adjacent anatomic structures were observed as displacement of the mandibular canal(46.5％) and maxillary sinus or nasal cavity(72.2％).

• The Journal of Korean Academy of Prosthodontics
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• v.50 no.4
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• pp.324-329
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• 2012

Excessive tooth wear causes loss of tooth structure, disharmony of occlusal plane, functional and esthetic problems. Although the decrease of occlusal vertical dimension may be compensated by growth of alveolar bone, if the length of tooth is not enough for the retention of restoration, minimum increase of occlusal vertical dimension is required without discomfort of the patient. In this case, 33-year-old woman drinks more than 1 liter of soft drinks a day and has bruxism in night time, visited in Seoul National University Dental Hospital with chief complaint of generalized tooth wear and related esthetic and functional problems. It was considered as a loss of occlusal vertical dimension based on the accelerated tooth wear caused by erosion and bruxism and facial appearance, phonetic, esthetic, functional evaluations. It was planned to raise occlusal vertical dimension by provisional restoration two times for patient's adaptation, 3 mm and 2 mm each, total 5 mm. Confirming no discomfort and clinical symptom during total 16 weeks after restoration with provisional fixed restoration, it was restored with porcelain fused to gold crown and bridge. Because the patient was young woman, anterior teeth were restored with collarless porcelain fused to gold crown. This case presents that satisfactory esthetic and functional result by full mouth rehabilitation with increase of occlusal vertical dimension.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.3
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• pp.407-412
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• 2002

The primary cause of missing teeth vary depending on the region. The loss of posterior teeth is mainly due to dental caries, whereas that of the anterior teeth occur primarily due to trauma at the age of standing and walking and secondarily from the rampant dental caries. Particularly, reduction of the arch length in the cases of premature loss of primary teeth may compromise the eruption of succedaneous permanent teeth. This may result in crowding and impaction of the permanent teeth, and asymmetry of arch, thus a careful consideration for space maintenance should be made in such cases. Space maintainer is required in the case of premature loss of primary posterior teeth, because space loss result from the approximate and centrifugal movement of the neighboring teeth. Generally, in the case of primary incisor, space loss occurs when 1) tooth contact is relevant, 2) crowding in primary dentition is present, and 3) a primary incisor is lost before the eruption of primary canine. Contrarily, in the case of primary dentition with interdental space, space loss will not be observed, mostly when a primary incisor is lost after the eruption of primary canine. Thus, using a space maintainer in cases of premature loss of primary incisor has been introduced primarily not for the purpose of space maintaining but for an aesthetic purpose, prevention of parafunctional oral habits such as tongue thrust, and of pronunciation. Additionally, few case studies have been reported of space loss in cases of premature loss of primary incisor. This study is to report cases of the space loss following the premature loss of primary incisors observed in children.