• The Journal of Advanced Prosthodontics
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• v.5 no.4
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• pp.440-447
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• 2013

PURPOSE. Template-guided implant therapy has developed hand-in-hand with computed tomography (CT) to improve the accuracy of implant surgery and future prosthodontic treatment. In our present study, the accuracy and causative factors for computer-assisted implant surgery were assessed to further validate the stable clinical application of this technique. MATERIALS AND METHODS. A total of 102 implants in 48 patients were included in this study. Implant surgery was performed with a stereolithographic template. Pre- and post-operative CTs were used to compare the planned and placed implants. Accuracy and related factors were statistically analyzed with the Spearman correlation method and the linear mixed model. Differences were considered to be statistically significant at $P{\leq}.05$. RESULTS. The mean errors of computer-assisted implant surgery were 1.09 mm at the coronal center, 1.56 mm at the apical center, and the axis deviation was $3.80^{\circ}$. The coronal and apical errors of the implants were found to be strongly correlated. The errors developed at the coronal center were magnified at the apical center by the fixture length. The case of anterior edentulous area and longer fixtures affected the accuracy of the implant template. CONCLUSION. The control of errors at the coronal center and stabilization of the anterior part of the template are needed for safe implant surgery and future prosthodontic treatment.

• Journal of Internet of Things and Convergence
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• v.2 no.4
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• pp.15-20
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• 2016

This paper describes the construction of knowledge data retrieval management system based on medical image CT. The developed system is aimed to improve the efficiency of the hospital by reading the medical images using the intelligent retrieval technology and diagnosing the patient 's disease name. In this study, the medical image DICOM file of PACS is read, the image is processed, and feature values are extracted and stored in the database. We have implemented a system that retrieves similarity by comparing new CT images required for medical treatment with the feature values of other CTs stored in the database. After converting 100 CT dicom provided for academic research into JPEG files, Code Book Library was constructed using SIFT, CS-LBP and K-Mean Clustering algorithms. Through the database optimization, the similarity of the new CT image to the existing data is searched and the result is confirmed, so that it can be utilized for the diagnosis and diagnosis of the patient.

• Transactions on Electrical and Electronic Materials
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• v.4 no.2
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• pp.29-34
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• 2003

Ferroelectric YMnO$_3$ thin films were etched with Ar/C1$_2$ and CF$_4$/C1$_2$ Plasma. The maximum etch rate of YMnO$_3$ thin film was 300 $\AA$/min at a Cl$_2$/Ar gas mixing ratio of 8/2, an RF power of 800 W, a do bias of-200 V, a chamber pressure of 15 mTorr, and a substrate temperature of 3$0^{\circ}C$. From the X-ray photoelectron spectroscopy (XPS) analysis, yttrium was not only etched by chemical reactions with Cl atoms, but also assisted by Ar ion bombardments in Ar/C1$_2$ plasma. In CF$_4$/C1$_2$ plasma, yttrium formed nonvolatile YF$_{x}$ compounds and remained on and the etched surface of YMnO$_3$. Manganese etched effectively by forming volatile MnCl$_{x}$ and MnF$_{y}$. From the X-ray diffraction (XRD) analysis, the (0004) diffraction peak intensity of the YMnO$_3$ thin film etched in Ar/Cl$_2$ plasma shows lower than that in CF$_4$/Cl$_2$ plasma. It indicates that the crystallinty of the YMnO$_3$ thin film is more easily damaged by the Af ion bombardment than the changes of stoichiometry due to nonvolatile etch by-products.cts.s.

• Biomedical Science Letters
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• v.26 no.3
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• pp.186-191
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• 2020

This study was designed to investigate the median nerve cross-sectional area of the upper extremity which is the main cause of CTS in the 20s and 30s. The median nerve cross-sectional area (MNC-area) of each part of the upper limb was measured in healthy 20s and 30s females and males without neurological diseases or other diseases. This MNC-area was compared with the hand, wrist, finger, and other body indexes. The research group was divided into 20s female and male groups, and the 30s were also divided into female and male groups. In the comparison between the ages, the hand, and wrist configurations in the 30s were significantly higher than those of the 20s. The mean median nerve cross-sectional area was significantly larger in the male group than in the female group in both 20s and 30s, and it was larger in both men and women than in the 20s. Hand and wrist configurations were also positively correlated with the median nerve cross-sectional area in both 20s and 30s. The median values of hand ratio and wrist ratio were 2.26 and 0.65, respectively. This median value of hand ratio was inversely correlated with the median nerve cross-sectional area. The median nerve cross-area of the 20s was 6.88~7.38 ㎟ in the male group and 5.69~6.99 ㎟ in the female group, respectively. The median nerve cross-area of the 30s was 6.32~8.89 ㎟ in the male group and 6.15~7.17 ㎟ in the female group, respectively. The mean median nerve cross-sectional area was positively correlated with body mass index in both groups. Most of the variables were higher in their 30s than in their 20s.

• Molecules and Cells
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• v.38 no.3
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• pp.279-284
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• 2015

Obatoclax, a pan-Bcl2 inhibitor, shows antitumor activities in various solid malignancies. Bcl2-deficient mice have shown the importance of Bcl2 in osteoclasts, as the bone mass of the mice was increased by the induced apoptosis of osteoclasts. Despite the importance of Bcl2, the effects of obatoclax on the proliferation and differentiation of osteoclast precursors have not been studied extensively. Here, we describe the anti-proliferative effects of obatoclax on osteoclast precursors and its negative role on fusion of the cells. Stimulation with low doses of obatoclax significantly suppressed the proliferation of osteoclast precursors in a dose-dependent manner while the apoptosis was markedly increased. Its stimulation was sufficient to block the activation of ERK MAP kinase by RANKL. The same was true when PD98059, an ERK inhibitor, was administered to osteoclast precursors. The activation of JNK1/2 and p38 MAP kinase, necessary for osteoclast differentiation, by RANKL was not affected by obatoclax. Interestingly, whereas the number of TRAP-positive mononuclear cells was increased by both obatoclax and PD98059, fused, multinucleated cells larger than $100{\pm}m$ in diameter containing more than 20 nuclei were completely reduced. Consistently, obatoclax failed to regulate the expression of osteoclast marker genes, including c-Fos, TRAP, RANK and CtsK. Instead, the expression of DC-STAMP and Atp6v0d2, genes that regulate osteoclast fusion, by RANKL was significantly abrogated by both obatoclax and PD98059. Taken together, these results suggest that obatoclax down-regulates the proliferation and fusion of osteoclast precursors through the inhibition of the ERK1/2 MAP kinase pathway.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.3
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• pp.442-450
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• 2015

Climate temperature affects animal production. This study was conducted to evaluate whether climatic conditions affect beef carcass characteristics of Korean cattle steers. The monthly carcass characteristics of Korean cattle steers (n = 2,182,415) for 8 yr (2006 through 2013) were collected from the Korean Institute for Animal Products Quality Evaluation. Daily climate temperature (CT) and relative humidity (RH) data were collected from the Korean Meteorological Administration. Weather conditions in South Korea during summer were hot and humid, with a maximum temperature of $28.4^{\circ}C$ and a maximum RH of 91.4%. The temperature-humidity index (THI), calculated based on CT and RH, ranges from 73 to 80 during summer. Winter in South Korea was cold, with a minimum temperature of $-4.0^{\circ}C$ and a wind-chill temperature of $-6.2^{\circ}C$. Both marbling score (MS) and quality grade (QG) of Korean cattle steer carcasses were generally best (p<0.05) in autumn and worst in spring. A correlation analysis showed that MS and QG frequencies were not associated (p>0.05) with CT. Yield grade (YG) of Korean cattle steer carcasses was lowest (p<0.05) in winter (November to January) and highest in spring and summer (May to September). A correlation analysis revealed that YG frequency was strongly correlated ($r{\geq}0.71$; p<0.01) with CT and THI values. The rib eye area, a positive YG parameter, was not associated with CT. Backfat thickness (BT), a negative YG factor, was highest in winter (November and December). The BT was strongly negatively correlated ($r{\leq}-0.74$; p<0.01) with CTs. Therefore, the poor YG during winter is likely due in part to the high BT. In conclusion, YG in Korean cattle steer carcasses was worst in winter. QGs were not associated with winter or summer climatic conditions.

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2331-2334
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• 2014

$Cu_2SnSe_3$ (CTSe) and $Cu_2ZnSnSe_4$ (CZTSe) nanoparticles were synthesized by sonochemical reactions under multibubble sonoluminescence (MBSL) conditions. First, $Cu_2SnSe_3$ nanoparticles were synthesized by the sonochemical method with an 85% yield, using CuCl, $SnCl_2$, and Se. Second, ZnSe was coated on the CTSe nanoparticles by the same method. Then, they were transformed into CZTSe nanoparticles of 5-7 nm diameters by heating them at $500^{\circ}C$ for 1 h. The ratios between Zn and Sn could be controlled from 1 to 3.75 by adjusting the relative concentrations of CTSe and ZnSe. With relatively lower Zn:Sn ratios (0.75-1.26), there are mostly CZTSe nanoparticles but they are believed to include very small amount of CTS and ZnSe particles. The prepared nanoparticles show different band gaps from 1.36 to 1.47 eV depending on the Zn/Sn ratios. In this sonochemical method without using any toxic or high temperature solvents, the specific stoichiometric element Zn/Sn ratios in CZTSe were controllable on demand and their experimental results were always reproducible in separate syntheses. The CZTSe nanoparticles were investigated by using X-ray diffractometer, a UV-Vis spectrophotometer, scanning electron microscope, Raman spectroscopy, and a high resolution-transmission electron microscope.

• Journal of Convergence for Information Technology
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• v.10 no.6
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• pp.1-7
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• 2020

The demand on the underwater communications is extremely increasing in searching for underwater resources, marine expedition, or environmental researches, yet there are many problems with the wireless communications because of the characteristics of the underwater environments. Especially, with the underwater wireless networks, there happen inevitable delay time and spacial inequality due to the distances between the nodes. To solve these problems, this paper suggests a new solution based on ALOHA-Q. The suggested method use random NAV value. and Environments take reward through communications success or fail. After then, The environments setting NAV value from reward. This model minimizes usage of energy and computing resources under the underwater wireless networks, and learns and setting NAV values through intense learning. The results of the simulations show that NAV values can be environmentally adopted and select best value to the circumstances, so the problems which are unnecessary delay times and spacial inequality can be solved. Result of simulations, NAV time decreasing 17.5% compared with original NAV.

• Nuclear Engineering and Technology
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• v.44 no.1
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• pp.61-70
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• 2012

In this study, a simple post-reconstruction dual-energy computed tomography (CT) method is proposed. A dual-energy CT algorithm for monochromatic x-rays was adopted and applied to the dual-energy CT of polychromatic x-rays by assigning a representative mono-energy. The accuracy of algorithm implementation was tested with mathematical phantoms. To test the sensitivity of this algorithm to the inaccuracy of representative energy value in energy values, a simulation study was performed with mathematical phantom. To represent a polychromatic x-ray energy spectrum with a single-energy, mean energy and equivalent energy were used, and the results were compared. The feasibility of the proposed method was experimentally tested with two different micro-CTs and a test phantom made of polymethyl methacrylate (PMMA), water, and graphite. The dual-energy calculations were carried out with CT images of all possible energy pairs among 40, 50, 60, 70, and 80 kVp. The effective atomic number and the electron density values obtained from the proposed method were compared with theoretical values. The results showed that, except the errors in the effective atomic number of graphite, most of the errors were less than 10 % for both CT scanners, and for the combination of 60 kVp and 70 kVp, errors less than 6.0 % could be achieved with a Polaris 90 CT. The proposed method shows simplicity of calibration, demonstrating its practicality and feasibility for use with a general polychromatic CT.

• Journal of Nutrition and Health
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• v.31 no.6
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• pp.1014-1023
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• 1998

The influences of fish oil and different levels of vitamin I supplement on hepatocellular chemical carcinogenesis have been studied. Male Sprague-Dawley rats received diethylnitrosamine (DEN)(200mg/kg body weight) and were subjected to two-thirds partial hepatectomy to induce murine chemical hepatocarcinogenic procedure. Placental glutathione S-transferase(GST-P) positive foci area, antioxidant enzymes(Cu/Zn-superoxide dismutase(SOD), catalase, glutathione reductase (GR), total- glutathione peroxidase (TGPx), glutathione S -transferase (GST)), glucose 6-phosphatase (G6Pase) activities, and lipid peroxidation of microsomes(thiobarbituric acid reactive substances (TBARS)) were measured. Experimental animals were fed 15% corn or fish oil with 0, 40, 1,000, 10,000IU vitamin E /kg diet for 8 weeks. Vitamin E supplements decreased the area of GST-P positive foci in both groups. The higher the vitamin E levels, the smaller the area of GST-P positive foci were noticed. Compared to 0 IU vitamin E, 40 IU in corn oil and 1,000 IU in fish oil groups were effective in decreasing G57-P positive foci area. Fish oil groups tended to have smaller area of GST-P positive foci. fish oil groups showed lower body weight, lower activities of Cu/Zn-SOD and TGPx, higher TBARS contents, higher activities of GST, catalase, G6Pase, GR and higher liver/body ratio than corn oil groups. As the level of vitamin I increased, GST-P positive foci count, catalase activities, and TBARS tended to decrease. G6Pase activities tended to increase in both groups. At higher vitamin E levels, GST activities tended to decrease in fish oil groups. These results suggest that vitamin I has suppressive offects on hepatocellular chemical carcinogenesis probably through antioxidant eH:cts decreasing TBARS contents, $H_2O$$_2$, and organic peroxides. fish oil tended to have greated suppressive offects than corn oil on hepatocellular carcinogenesis. (Korean J Nutrition 31(6) : 1014-1023, 1998)