2,396 research outputs found
Investigation of the SH3BP2 Gene Mutation in Cherubism
Cherubism is a rare developmental lesion of the jaw that is generally inherited as an autosomal dominant trait. Recent studies have revealed point mutations in the SH3BP2 gene in cherubism patients. In this study, we examined a 6-year-old Korean boy and his family. We found a Pro418Arg mutation in the SH3BP2 gene of the patient and his mother. A father and his 30-month-old younger brother had no mutations. Immunohistochemically, the multinucleated giant cells proved positive for CD68 and tartrate-resistant acid phosphatase (TRAP). Numerous spindle-shaped stromal cells expressed a ligand for receptor activator of nuclear factor kB (RANKL), but not in multinucleated giant cells. These results provide evidence that RANKL plays a critical role in the differentiation of osteoclast precursor cells to multinucleated giant cells in cherubism. Additionally, genetic analysis may be a useful method for differentiation of cherubism.</p
Nano-structure fabrication of GaAs using AFM tip-induced local oxidation method: different doping types and plane orientations
In this study, we have fabricated nano-scaled oxide structures on GaAs substrates that are doped in different conductivity types of p- and n-types and plane orientations of GaAs(100) and GaAs(711), respectively, using an atomic force microscopy (AFM) tip-induced local oxidation method. The AFM-induced GaAs oxide patterns were obtained by varying applied bias from approximately 5 V to approximately 15 V and the tip loading forces from 60 to 180 nN. During the local oxidation, the humidity and the tip scan speed are fixed to approximately 45% and approximately 6.3 μm/s, respectively. The local oxidation rate is further improved in p-type GaAs compared to n-type GaAs substrates whereas the rate is enhanced in GaAs(100) compared to and GaAs(711), respectively, under the identical conditions. In addition, the oxide formation mechanisms in different doping types and plane orientations were investigated and compared with two-dimensional simulation results
Proto-type installation of a double-station system for the optical-video-detection and orbital characterisation of a meteor/fireball in South Korea
We give a detailed description of the installation and operation of a
double-station meteor detection system which formed part of a research &
education project between Korea Astronomy Space Science Institute and Daejeon
Science Highschool. A total of six light-sensitive CCD cameras were installed
with three cameras at SOAO and three cameras at BOAO observatory. A
double-station observation of a meteor event enables the determination of the
three-dimensional orbit in space. This project was initiated in response to the
Jinju fireball event in March 2014. The cameras were installed in
October/November 2014. The two stations are identical in hardware as well as
software. Each station employes sensitive Watec-902H2 cameras in combination
with relatively fast f/1.2 lenses. Various fields of views were used for
measuring differences in detection rates of meteor events. We employed the
SonotaCo UFO software suite for meteor detection and their subsequent analysis.
The system setup as well as installation/operation experience is described and
first results are presented. We also give a brief overview of historic as well
as recent meteor (fall) detections in South Korea. For more information please
consult http://meteor.kasi.re.kr .Comment: Technical/instrumentation description of a professional meteor
detection system, 23 pages, 20 figures (color/monochrome), 5 tables,
submitted to the Journal of Korean Astronomical Society (JKAS,
http://jkas.kas.org/, http://jkas.kas.org/history.html
Universal convex covering problems under translation and discrete rotations
We consider the smallest-area universal covering of planar objects of
perimeter 2 (or equivalently closed curves of length 2) allowing translation
and discrete rotations. In particular, we show that the solution is an
equilateral triangle of height 1 when translation and discrete rotation of
are allowed. Our proof is purely geometric and elementary. We also give
convex coverings of closed curves of length 2 under translation and discrete
rotations of multiples of and . We show a minimality of the
covering for discrete rotation of multiples of , which is an equilateral
triangle of height smaller than 1, and conjecture that the covering is the
smallest-area convex covering. Finally, we give the smallest-area convex
coverings of all unit segments under translation and discrete rotations
for all integers
Metal work-function-dependent barrier height of Ni contacts with metal-embedded nanoparticles to 4H-SiC
Metal, typically gold [Au], nanoparticles [NPs] embedded in a capping metal contact layer onto silicon carbide [SiC] are considered to have practical applications in changing the barrier height of the original contacts. Here, we demonstrate the use of silver [Ag] NPs to effectively lower the barrier height of the electrical contacts to 4H-SiC. It has been shown that the barrier height of the fabricated SiC diode structures (Ni with embedded Ag-NPs) has significantly reduced by 0.11 eV and 0.18 eV with respect to the samples with Au-NPs and the reference samples, respectively. The experimental results have also been compared with both an analytic model based on Tung's theory and physics-based two-dimensional numerical simulations
Optical pulse differentiation based on a resonant slow & fast light system
We experimentally demonstrate that temporal differentiation of optical pulses can be realized in a slow & fast light system based on a resonance. The waveform of a 13 ns Gaussian pulse was experimentally first-order differentiated
Accelerated Ulcer Healing and Resistance to Ulcer Recurrence with Gastroprotectants in Rat Model of Acetic Acid-induced Gastric Ulcer
Quality of ulcer healing (QOUH) is defined as ideal ulcer healing featuring with the fine granular ulcer scar, high functional restoration and the resistance to recurrence. This study was designed to compare the rates of QOUH achievement in rat gastric ulcer model between acid suppressant treated group and gastroprotectant treated group accompanied with elucidations of molecular mechanisms. Serosal injection of acetic acids for generating gastric ulcer and intraperitoneal (ip) injection of recombinant interleukin 1-beta (IL-1β) for recurring healed ulcer was done in SD rats. The 72 rats were divided into three groups according to treatment as follows; Group I, no further treatment, Group II, 8 weeks treatment of omeprazole, and Group III, 8 weeks of gastroprotectant treatment. IL-1β was administered for ulcer recurrence after 28 weeks of acetic acid injection. At four weeks after gastric ulcerogenesis, 58.3% (7/12) of active gastric ulcer were converted to healing stage in Group III, but 16.7% (2/12) in Group II and none in Group I, for which significant levels of epidermal growth factor, mucin, and pS2/trefoil peptide1 were contributive to these accelerated healings of Group III. ip injections of rIL-1β (200 µg/kg) at 28 weeks after acetic acid injection led to 100% of ulcer recurrence in Group I and 75.0% in Group II, but only 16.7% of Group III rats showed ulcer recurrence. Significantly attenuated levels of inflammatory cytokines including IL-2, transforming growth factor-alpha (TNF-α), cyclooxygenase-2 (COX-2), nitrotyrosine were responsible for the resistance to ulcer recurrence in Group III. Conclusively, gastroprotectant might be prerequisite in order to achieve ideal QOUH through significant inductions of remodeling
Erratum: Nation-Wide Korean Breast Cancer Data from 2008 Using the Breast Cancer Registration Program
nation-wide breast cancer data and analyzed the data using their online registration program biannually. The purpose of this study was to evaluate the characteristics of Korean breast cancer from 2008 and examine chronological based patterns. Methods: Data were collected from 38 medical schools (67 hospitals), 20 general hospitals, and 10 private clinics. The data on the total number, gender, and age distribution were collected through a questionnaire as well as other detailed data analyzed via the online registration program. Results: In 2008, there were 13,908 patients who were newly diagnosed with breast cancer. The crude incidence rate of female breast cancer was 57.3 among 100,000 and the median age was 49 years. The age distribution had not changed since the initial survey; however the proportion of postmenopausal patients had increased and median age was older than the past. In staging distribution, the proportion of early breast cancer (stage 0, I) was 47.2 % with, breast-conserving surgery performed in 58 % and mastectomy in 39.5%. Conclusion: Compared to past data, the incidence of breast cancer in Korea continues to rise. Furthermore, the proportion of those detected by screening and breast conservation surgery has increased remarkably. To understand the patterns of Korean breast cancer, the nation-wide data should continuously investigated
Ultraviolet light and laser irradiation enhances the antibacterial activity of glucosamine-functionalized gold nanoparticles
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