• Journal of Dental Rehabilitation and Applied Science
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• v.28 no.2
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• pp.119-126
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• 2012

State of problem: Cement-retained implant-supported prostheses are routinely used in dentistry. The use of high strength cements has become more popular with the increasing confidence in the stability of the implant-abutment screw connection and the high survival rates of osseointegrated implants. No clinical data on retention of metal copings using CAD/CAM. To evaluate retention of metal copings using CAD/CAM system bonded to short titanium abutment with four different cements and compare retentive strength of metal copings with sandblasting or without sandblasting before cementation. Forty titanium abutment blocks were fabricated and divided into 4 groups of 10 samples each. Forty metal copings with occlusal hole to allow for retention testing were fabricated using CAD/CAM technology. The four cements were Fujicem(Fuji, Japan), Maxcem Elite(Kerr, USA), Panavia F2.0(Kurarary, Japan) and Superbond C&B(Sunmedical, Japan). The copings were cemented on the titanium abutment according to manufacture's recommendation. All samples were stored for 24h at 37oC in 100% humidity and tested for retention using universal testing machine(Instron) at a crosshead speed of 1.0mm/min. Force at retentive failure was recorded in Newton. The mode of failure was also recorded. Means and standard deviations of loads at failure were analyzed using ANOVA and Paired t-test. Statistical significance was set at P<0.05. Panavia F2.0 provided significantly higher retentive strength than Fujicem, Maxcem Elite(P<0.05). Sandblasting significantly increased bond strength(P<0.05). The mode of failure was cement remaining principally on metal copings. Within the limitation of this study, Panavia F2.0 showed significantly stronger retentive strength than Fujicem, Maxcem Elite(p<0.05). The Ranking order of the cements to retain the copings was Panavia F2.0, Fujicem = Maxcem Elite. Sandblasting significantly increased bond strength(P<0.05). The retentive strength of metal copings on implant abutment were influenced by surface roughness and type of cements.

• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.1
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• pp.73-82
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• 2009

Injectable calcium phosphate cement (CPC) has been used as bone substitute successfully due to good biocompatibility and osteoconductivity. One of the important mechanical characteristics of CPC is flowablility, which can be evaluated by measuring rheological parameters. However, there have been few studies that measured rheological properties of CPC. The purpose of this study was to evaluate the effects of temperature and concentrations of 2 kinds of setting solutions, hydroxyprophyl methylcellulose (HPMC) and polyacrylic acid (PAA), on rheological properties of CPC. The CPC used was dicalcium phosphate dihydrate (DCPD). Rheological properties of CPC paste were measured using rheometer. The effect of concentrations of each solution (2% and 1% HPMC and 35% and 17.5% PAA) was evaluated. The effect of temperature ($25^{\circ}C$ and $37^{\circ}C$) on the rheological properties of CPC was also investigated. The statistical analysis was carried out with Mann-whitney test with Bonferronis collection. CPC with both setting solutions showed shear thinning behavior. Higher concentrations of setting solution (2% HPMC and 35% PAA) produced significantly higher viscosity than lower concentrations of setting solution (1% HPMC and 17.5% PAA). CPC with HPMC showed significantly higher viscosity at $37^{\circ}C$ that at $25^{\circ}C$. CPC with PAA showed lower viscosity at $37^{\circ}C$ than at $25^{\circ}C$, although the difference was not statistically significant. The results showed that CPC with HPMC or PAA solutions are pseudoplastic and the concentrations of setting solutions and temperature may have an effect on the rheological properties of CPC paste. These results showed that the flowability of injectable CPC could be improved by use of increasing frequency of oscillation. In clinical practice, the use of ultrasonic vibration would be helpful in application of injectable CPC. CPC with HPMC could be more easily applicated at $25^{\circ}C$ than $37^{\circ}C$. The use of lower concentrations of HPMC and PAA solution would be beneficial in terms of flowability.

• Tuberculosis and Respiratory Diseases
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• v.53 no.2
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• pp.136-147
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• 2002

Background : Interstitial lung disease has various manifestations that are differentiated by their pathology, progress and treatment. However, all manifestations eventually progresses to pulmonary fibrosis. Recent studies have shown that apoptosis of pulmonary epithelial cells might be related to pulmonary fibrosis. The correlation of the apoptotic index with the clinical manifestations, pathological findings, HRCT findings and the response to treatment were examined. Materials and Methods : Twenty subjects (14 men, 16 women), who had been diagnosed with interstitial lung disease through an open lung biopsy, were enrolled in this study. The subtypes were one AIP, two NIP, eight BOOP, and seven UIP cases. The apoptotic index was scaled from 0-2 depending on the fraction of positive staining cells by TUNEL method. The clinical severity was assessed by a modification of a previously developed CRP scoring system. The pathologic scores were based on 4 components: fibrosis, cellularity, desquamation, and granulation. In the HRCT study, each lobe was scored by the radiologists on a scale for both fibrosis and ground-glass attenuation. The treatment response was assessed by an increase in more than 10% of the CRP score, and comparing the results 3 months before and after treatment. Results : The apoptotic index showed no correlation with the CRP and HRCT scoring system. The apoptotic index correlated with the pathologic elements including fibrosis, cellularity and the desquamation score (p<0.05). Of the 16 patients who received corticosteroid therapy, 9 patients (56.3%) responded to therapy. There was no correlation between the response to corticosteroid and the apoptotic index. In the case of patients with acute and subacute ILD, the apoptotic index showed a correlation with the cellularity, desquamation, and the total histological score (p<0.05). In the case of patients with chronic ILD, the apoptotic index correlated with the fibrosis and cellularity score (p<0.05). Conclusion : Apoptosis of the pulmonary epithelial cells is implicated in the pathogenesis of interstitial lung disease particularly on a pathological basis.

• Korean Chemical Engineering Research
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• v.58 no.1
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• pp.29-35
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• 2020

In this study, the skin permeability was measured by adding cell penetrating peptides, arginine oligomers; (tetra-D-arginine (R4) and hexa-D-arginine (R6)) to little skin-permeable anti-wrinkle peptides (GHK, GHK-Cu, and Pal-GHK), and the results were analyzed by the following six cases. First, in cases where only anti-wrinkle peptides were contained, copper ions (Cu₂⁺) and palmitic acid enhanced the transdermal permeability. Second, when arginine oligomers (R4, R6) were added to GHK, arginine oligomers (R4, R6) increased percutaneous permeability, and R4 showed better percutaneous permeability. Third, the addition of R4 and R6 to GHK-Cu resulted in increased percutaneous transmittance, followed by R6 < R4 percutaneous transmittance. Fourth, when R4 and R6 were added to Pal-GHK, the percutaneous permeability increased with results in R6 < R4 order. Fifth, when R4 was added to GHK, GHK-Cu, and Pal-GHK, the transdermal permeability increased in the order of GHK+R4 < GHK-Cu+R4 < Pal-GHK+R4. Finally, the addition of R6 to GHK, GHK-Cu and Pal-GHK also resulted in increased percutaneous transmittance in the order of GHK+R4 < GHK-Cu+R4 < Pal-GHK+R4. This study provides optimal conditions for enhancing skin absorption of anti-wrinkle peptides GHK, GHK-Cu, and Pal-GHK, and propose a wide range of applications in anti-wrinkle functional cosmetics by suggesting ways to maximize their efficacy.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.12C
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• pp.1288-1298
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• 2002

To implement elliptic curve cryptosystem in GF(2$\^$m/) at high speed, a fast divider is required. Although bit-parallel architecture is well suited for high speed division operations, elliptic curve cryptosystem requires large m(at least 163) to support a sufficient security. In other words, since the bit-parallel architecture has an area complexity of 0(m$\^$m/), it is not suited for this application. In this paper, we propose a new serial-in serial-out systolic array for computing division operations in GF(2$\^$m/) using the standard basis representation. Based on a modified version of tile binary extended greatest common divisor algorithm, we obtain a new data dependence graph and design an efficient bit-serial systolic divider. The proposed divider has 0(m) time complexity and 0(m) area complexity. If input data come in continuously, the proposed divider can produce division results at a rate of one per m clock cycles, after an initial delay of 5m-2 cycles. Analysis shows that the proposed divider provides a significant reduction in both chip area and computational delay time compared to previously proposed systolic dividers with the same I/O format. Since the proposed divider can perform division operations at high speed with the reduced chip area, it is well suited for division circuit of elliptic curve cryptosystem. Furthermore, since the proposed architecture does not restrict the choice of irreducible polynomial, and has a unidirectional data flow and regularity, it provides a high flexibility and scalability with respect to the field size m.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.6
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• pp.778-783
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• 2015

We studied about the strength characteristics of the FRP bonding method due to reduce accident on the oceans and protect life for my people. We test tension and bending strength of butt joint, lap joint, V-scarf joint, X-scarf joint. The result of test, it's pattern is similar both tension and bending strength. Tension strength and bending strength was excellent in order to X-scarf-butt joint-V-scarf-lap joint. The tension strength is the best properties X-scarf showed a 57% strength rate of the basic material, and bending strength showed a 77% strength rate of the basic material. Overall, the X-scarf 12t joint has most excellent properties of tension and bending strength. The lap joint has worst properties of tension and bending strength. We have to test having different over-lay of V-scarf and X-scarf joint each 12t, 16t, 20t. V-scarf of 20t over-lay has excellent character of tension and bending strength. But X-scarf of 12t over-lay has excellent character of tension and bending strength. The results are shown to the contrary. The ship is received a lot of stress. it's hard to compare a direction both actual and test. But we can acknowledge material basic characteristic of strength through tension and bending test. We give the four repair method; butt joint, lap joint, V-scarf joint, X-scarf joint and the reduced ratio in comparison with basic material; In addition give the separated data for V-scarf and X-scarf characteristic of 12t, 16t, 20t overlay length. For our study repair man can select good repair method in his work station.

• The Journal of Dong Guk Oriental Medicine
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• v.8 no.2
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• pp.131-154
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• 2000

Nan Jing(Difficult Classic), as a catechism, describes in detail and deeply the ideas in Nei Jing(Huangdi's Internal Classic). The description of Nan Jing is focused on basic theories including theories about some disease and is excellent in identification and analysis. The contents of Nan Jing are as follows: 1-23 Nan-pulse and pulse condition, 24~29 Nan-channels and collaterals, 30~47 Nan-viscera and bowels(Zang Fu organs), 48~61 Nan-disease, 62~68 Nan-acupuncture points, 69~91 Nan-acupuncture. Especially, diagnosis techniques in Nan Jing make 'Only method of cunkou pulse taking' that is a technique for feeling the pulse widely applied in these days in Oriental medicine clear. Thus, this book adjusts the theory of pulse and pulse condition given in 1~23 Nan of 'The Study of Nan Jing' in order to enhance an understanding about the theory of pulse and pulse condition. The text of 1~23 Nan about pulse lore centers on all pulse of human body interconnected each other and cunkou, both ends of the pulse, and contrasts regular pulse with irregular pulse. 1. 10 Nan describes the theory about five kinds of evils and hardness and softness, and unique pulse condition of each bowels. 2. 13 Nan explains that the relative difficulty of medical treatment is determined by the degree of balance or unbalance among three factors-colors, pulse and pulse condition, flesh shape. 3. 14 Nan divides pulse and pulse condition into slow pulse and rapid pulse, and explains separately abnormality, great loss of semen, death caused by slow pulse, and abnormality, great loss of semen, death caused by rapid pulse. 4. 15 Nan about taut pulse(弦), full pulse(鉤), floating pulse(毛), deep pulse(石脈) describes that pulse and pulse condition differs according to four seasons. Therefore, Nan Jing establishes clearly techniques of feeling the pulse in 'Only method of cunkou pulse taking(獨取寸口)' and advances the theory of Nei Jing. Futhermore, Nan Jing is more valuable in that it suggests unique theory different with Nei Jing.

• Radiation Oncology Journal
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• v.15 no.1
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• pp.57-64
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• 1997

Purpose : Before we report the results of curative radiotherapy in cervix cancer patients, we review the significance and safety of our dose specification methods in the brachytherapy system to have the insight of the potential Predictive value of doses at specified points. Matersials and Methods : We analyze the 리5 cases of cervix cancer patients treated with intracavitary brachytherapy in the lateral simulation film we draw the isodose curve and observe the absorbed dose rate of point A, the reference point of bladder(SBD) and rectum(SRD). In the sagittal view of Pelvic MRI film we demarcate the tumor volume(TV) and determine whether the prescription dose curve of point A covers the tumor volume adequately by drawing the isodose curve as correctly as possible. Also we estimate the maximum Point dose of bladder(MBD) and rectum(MRD) and calculate the inclusion area where the absorbed dose rate is higher than that of point A in the bladder(HBV) and rectum(HRV), respectively. Results : Of forty-five cases, the isodose curve of point A seems to cover tumor volume optimally in only 24(53%). The optimal tumor coverage seems to be associated not with the stage of the disease but with the tumor volume. There is no statistically significant association between SBD/SRD and MBD/MRD, respectively. SRD has statistically marginally significant association with HRV, while TV has statistically significant association with HBV and HRV. Conclusion : Our current treatment calculation methods seem to have the defect in the aspects of the nonoptimal coverage of the bulky tumor and the inappropriate estimation of bladder dose. We therefore need to modify the applicator geometry to optimize the dose distribution at the position of lower tandem source. Also it appears that the position of the bladder in relation to the applicators needs to be defined individually to define 'hot spots'.

• The Korean Journal of Food And Nutrition
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• v.29 no.3
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• pp.438-447
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• 2016

This study was conducted in order to investigate the physiochemical properties and antioxidative activity of red ginseng manufactured using the high temperature high pressure (HTHP) process, which is faster and simpler than the conventional process. According to increasing the steaming temperature, pressure and time, the content of minor non-polar ginsenosides, such as Rg3, Rk3, Rh4, Rk1 and Rg5 gradually increased. Also, the contents of acidic polysaccharide, total phenolic compounds and maltol gradually increased. Based on the results of the physiochemical properties and appearance quality, the optimum conditions of HTHP process were estimated as $140^{\circ}C$, $3kg/cm^2$ in 20 min. The total phenolic compounds and maltol contents of the HTHP process red ginseng (1.0% and 2.49 mg%, respectively) were higher than those of conventional red ginseng (0.23% and 0.60 mg%, respectively). In addition, the antioxidative activity was investigated using DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-aziono-bis(3-ethylbenzthiazoline-6-sulfonic acid)) radical scavenging activity. DPPH and ABTS radical scavenging activities of HTHP process red ginseng increased by 3.4 and 3.6 folds, respectively, compared with conventional red ginseng. In addition, total phenolic compounds and maltol contents, as well as the antioxidant activity of the HTHP process red ginseng were similar to black ginseng. The present results suggest that the HTHP process is available for the development of value-added red ginseng products.

• Applied Biological Chemistry
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• v.39 no.6
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• pp.482-487
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• 1996

Five barley and two oat varieties grown in Korea were investigated for soluble, insoluble, and total $(1{\to}3)$, $(1{\to}4)-{\beta}-D-glucans$. Total and insoluble ${\beta}-glucans$ after extraction of soluble ${\beta}-glucans$ with water were analyzed, and the soluble ${\beta}-glucans$ were calculated as the difference between total and insoluble ${\beta}-glucans$. The total ${\beta}-glucans$ in whole barleys were in a range of $3.3{\sim}5.6%$(average 4.4%), and those in pearled barleys were In a range of $3.3{\sim}7.1%$(average 5.2%). In whole barleys, on average, 54% of the ${\beta}-glucans$ was soluble and in pearled barley 46%. Whole oats contained $3.1{\sim}4.0%$ total ${\beta}-glucans$, and dehulling increased the groat ${\beta}-glucans$ contents to $4.0{\sim}4.8%$. Oats demonstrated considerably higher ${\beta}-glucans$ solubility of 84% than barley. ${\beta}-Glucans$ in barley and oats were rapidly extracted at the beginning of the extraction and almost all of the ${\beta}-glucans$ were extracted after $2{\sim}3 hr extraction. As extraction temperature increased from $23^{\circ}C$ to $45^{\circ}C$, more soluble ${\beta}-glucans$ were extracted. However, solubility of barley ${\beta}-glucans$ decreased at a relatively high temperature of $65^{\circ}C$. Steam-cooking reduced the analytical solubility of barley and oat ${\beta}-glucans$, while roasting seemed to render the ${\beta}-glucans$ of barley more soluble.