• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.11 no.1
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• pp.59-66
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• 1981

The dens evaginatus was a developmental variation which has arisen as a result of an evagination of inner enamel epithelium into the enamel organ. It has been given various. names by authors and was thought to be confined to Mongolian race. This study was performed to observe the incidence of dens evaginatus, and its ill-effects on the teeth and surrounding structures in 6356 Korean students and 10227 Korean adults. In plaster model, analysis was performed in accordance with forms and location of dens evaginatus on the. occlusal surface in the premolars. The pathologic changes caused by dens evaginatus were observed in paralleling periapical radiograms The results were as follows: 1. The prevalence of dens evaginatus in the student's group was 2.6%, and showed no sex predilection in the occurrence of evaginated teeth. 2. The sequence of dens evaginatus was in order of mandibular 2nd premolar, mandibular 1st premolar, maxillary 2nd premolar, and maxillary 1st premolar, respectively. 3. Of the cases with dens evaginatus, 73.5 % occured bilaterally. 4. The nipple form was the most frequent in respect of elevation of tubercle on the, occlusal surface. 5. In the base form of the tubercle, the occurrence of grooved form was the highest. 6. In the maxilla, those cases which the tubercle arose from the lingual ridge of the buccal cusp were most predominant. And in the mandible, those cases which the tubercle arose from the center of the occlusal surface were the most frequent. 7. The pulpal and periapical complications were shown in 24.4% of evaginated teeth in. periapical radiogram.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.46 no.5
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• pp.37-43
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• 2009

Streaming video service over wireless and mobile communication networks has received significant interests from both academia and industry recently. Specifically, mobile WiMAX (IEEE 802.16e) is capable of providing high data rate and flexible Quality of Service (QoS) mechanisms, supporting mobile streaming very attractive. However, we need to note that streaming videos can be partially deteriorated in their macroblocks and/or slices owing to errors on OFDMA subcarriers, as we consider that compressed video sequence is generally sensitive to the error-prone channel status of the wireless and mobile network. In this paper, we introduce an OFDMA subcarrier-adaptive mobile streaming server based on cross-layer design. This streaming server system is substantially efficient to reduce the deterioration of streaming video transferred on the subcarriers of low power strength without any modifications of the existing schedulers, packet ordering/reassembly, and subcarrier allocation strategies in the base station.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.4
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• pp.341-345
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• 2011

Genetic association study has been progressed in medicine along with advance in genetic technology. It focused on the individual differences in genotype due to errors occurring during DNA duplication, which can cause vulnerability to specific diseases. Polymorphism defines the varieties in phenotype due to those genetic variations. Polymorphism due to change in one DNA base sequence is called as a Single Nucleotide Polymorphism. In the near future, the evaluation of relative risk to specific disease according to SNP will be essential part of fundamental of medicine for the diagnosis, treatment and prevention. Dental caries and periodontal diseases has been first subject to genetic association study in dentistry and broaden out to other areas like bone formation and resorption. This article presents the current state of genetic association study and its application to dentistry.

• Journal of Life Science
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• v.16 no.1
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• pp.44-48
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• 2006

The gene for a L-aspartate $\beta-decarboxylase$ (ADC) from Enterococcus faecalis was cloned and sequenced. The gene comprised an open reading frame of 1,611 base pairs, which encodes a protein of 58,960 Da consisting of 536 amino acid residues. The gene was subcloned into an expression plasmid for overexpression of the ADC. The recombinant ADC was produced using E. coli as the host and purified to homogeneity. Our result showed that the ADC may be obtained from bacteria known nucleotide sequence. Thus, we suggest that high value L-alanine might be produced by low value aspartate.

• Smart Structures and Systems
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• v.12 no.3_4
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• pp.251-269
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• 2013

Measurement of deflections of certain bridges is usually hampered by corruption of the GPS signal by multipath associated with passing vehicles, resulting to unrealistically large apparent displacements. Field data from the Gorgopotamos train bridge in Greece and systematic experiments revealed that such bias is due to superimposition of two major effects, (i) changes in the geometry of satellites because of partial masking of certain satellites by the passing vehicles (this effect can be faced with solutions excluding satellites that get temporarily blocked by passing vehicles) and (ii) dynamic multipath caused from reflection of satellite signals on the passing trains, a high frequency multipath effect, different from the static multipath. Dynamic multipath seems to have rather irregular amplitude, depending on the geometry of measured satellites, but a typical pattern, mainly consisting of a baseline offset, wide base peaks correlating with the sequence of main reflective surfaces of the vehicles passing next to the antenna. In cases of limited corruption of GPS signal by dynamic multipath, corresponding to scale distortion of the short-period component of the GPS waveforms, we propose an algorithm which permits to reconstruct the waveform of bridge deflections using a weak fusion of GPS and RTS data, based on the complementary characteristics of the two instruments. By application of the proposed algorithm we managed to extract semi-static and dynamic displacements and oscillation frequencies of a historical railway bridge under train loading by using noisy GPS and RTS recordings. The combination of GPS and RTS is possible because these two sensors can be fully collocated and have complementary characteristics, with RTS and GPS focusing on the long- and short-period characteristics of the displacement, respectively.

• The KIPS Transactions:PartD
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• v.14D no.5
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• pp.459-470
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• 2007

A data stream is a massive unbounded sequence of data elements continuously generated at a rapid rate. Query processing for such a data stream should also be continuous and rapid, which requires strict time and space constraints. In most DSMS(Data Stream Management System), the selection predicates of continuous queries are grouped or indexed to guarantee these constraints. This paper proposes a new scheme tailed an ASC(Attribute Selection Construct) that collectively evaluates selection predicates containing the same attribute in multiple continuous queries. An ASC contains valuable information, such as attribute usage status, partially pre calculated matching results and selectivity statistics for its multiple selection predicates. The processing order of those ASC's that are corresponding to the attributes of a base data stream can significantly influence the overall performance of multiple query evaluation. Consequently, a method of establishing an efficient evaluation order of multiple ASC's is also proposed. Finally, the performance of the proposed method is analyzed by a series of experiments to identify its various characteristics.

• Korean Journal of Microbiology
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• v.53 no.2
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• pp.141-143
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• 2017

Caballeronia sordidicola strain PAMC 26577 was isolated from Cladonia sp., a lichen collected from Svalbard Archipelago in the Arctic Ocean. Draft genomic sequences of PAMC 26577 were determined using Illumina and 182 contigs were submitted to GenBank and N50 value was 159,226. The genome of PAMC 26577 was comprised of 8,334,211 base pairs and %G+C content was 59.4. The genome included 8 ribosomal RNA genes and 51 tRNA genes as non-coding sequences. Protein-coding genes were 8,065 in number and they included central metabolism genes as well as butanol/butyrate biosynthesis, polyhydroxybutyrate metabolism, serine cycle methylotrophy genes, and glycogen metabolism. Membrane transporters were more than two-hundreds in number, but sugar phosphotransferase system and TRAP transporters were lacking. PAMC 26577 lacked CRISPR-associated sequences and proteins. No transposable elements were observed and there were only limited number of phage remnant regions with 11 phage-related genes.

• ALGAE
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• v.21 no.2
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• pp.209-216
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• 2006

The characteristics of Peyssonnelia capensis Montagne (Peyssonneliaceae, Rhodophyta) from Jeju Island were investigated in order to clarify the species entity and re-evaluate taxonomic position. The morphological variations of the Peyssonnelia capensis from Jeju Island were divided into two types, the thin thallus type and the thick thallus type. The thin thallus type is characterized by thin, soft, orbicular, slightly lobed thallus with entire to undulate margin, and compact rhizoids. The thick thallus type has thick and stiff thallus with sinuate margin and scattered rhizoids, and has more branches than the thin thallus type. The basal layer and the epithallium of thin thallus type are similar to those of thick thallus types in their structure. However, the hypothallial cells of the thick thallus type are longer than those of the thin thallus type. The erect filament of thick thallus type has more cells than those of the thin thallus type. Tetrasporangial nemathecia are distinctly protruded. Mature tetrasporangia of this species are divided cruciately into four spores as those of other Peyssonneliaceae. In addition to their morphological and anatomical distinctness between two types, the nucleotide sequence analyses of SSU and ITS2 region make no differences among populations from Jeju and other localities in Korea. Therefore these two morphological variation may not base on genetic variation.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.407-409
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• 2006

Geochemical analyses carried out on samples collected from cores on and near the southern smit of Hydrate Ridge have advanced understanding by providing a clear contrast of the two major modes of marine gas hydrate occurrence. High concentrations (15%-40% of pore space) of gas hydrate occurring at shallow depths (0-40 mbsf) on and near the southern summit are fed by gas migrating from depths of as much as 2km within the accretionary prism. This gas carries a characteristic minor component of C2-C5 thermogenic hydrocarbons that enable tracing of migration pathways and may stabilize the occurrence of some structure II gas hydrate. A structure II wet gas hydrate that is stable to greater depths and temperatures than structure I methane hydrate may account for the deeper, faint second bottom simulating reflection (BSR2) that occurs on the seaward side of the ridge. The wet gas is migrating In an ash/turbidite layer that intersects the base of gas hydrate stability on the seaward side of and directly beneath the southern summit of Hydrate Ridge. The high gas saturation (>65%) of the pore space within this layer could create a two-phase (gas + solid) system that would enable free gas to move vertically upward through the gas hydrate stability zone. Away from the summit of the ridge there is no apparent influx of the gas seeping from depth and sediments are characterized by the normal sequence of early diagenetic processes involving anaerobic oxidation of sedimentary organic matter, initially linked to the reduction of sulfate and later continued by means of carbonate reduction leading to the formation of microbial methane.

• Animal cells and systems
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• v.5 no.2
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• pp.153-156
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• 2001

A key aspect of genomic research in the “post-genome era”is to associate sequence variations with heritable phenotypes. The most common variations in the human genome are single nucleotide polymorphisms (SNPs) that occur approximately once in every 500 to 1,000 bases. Although analyzing the phenotypic outcome of these SNPs is crucial to facilitate large-scale association studies of genetic diseases, detection of SNPs from an extended number of human DNA samples is often difficult, labor-intensive and time-consuming. Recent development in SNP detection methods using DNA microarrays and mass spectrophotometry has allowed automated high throughput analyses, but such equipments are not accessible to many scientists. In this study, we demonstrate that a simple PCR-based method using primers with a mismatched base at the 3'-end provides a fast and easy tool to identify known SNPs from human genomic DNA in a regular molecular biology laboratory. Results from this PCR amplification of specific alleles (PASA) analysis efficiently and accurately typed the Q576R polymorphism of human IL4 receptor from the genomic DNAs of 29 Koreans, including 9 samples whose genotype could not be discerned by the conventiona1 PCR-SSCP (single strand conformation polymorphism) method. Given the increasing attention to disease-associated polymorphisms in genomic research, this alternative technique will be very useful to identify SNPs in large-scale population studies.