• Restorative Dentistry and Endodontics
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• v.32 no.3
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• pp.222-235
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• 2007

The objectives of this study was to evaluate the effect of thermocycling on the ${\mu}TBS$ (microtensile bond strength) to dentin with four different adhesive systems to examine the bonding durability. Freshly extracted $3^{rd}$ molar teeth were exposed occlusal dentin surfaces, and randomly distributed into 8 adhesive groups 3-steps total-etching (Scotchbond Multi-Purpose Plus; SM, All Bond-2; AB), 2-steps total-etching (Single Bond; SB, One Step plus; OS), 2-steps self-etching (Clearfil SE Bond; SE, AdheSE AD) and single-step self-etching systems (Promp L-Pop; PL, Xeno III; XE) Each adhesive system in 8 adhesives groups was applied on prepared dentin surface as an instruction and resin composite (Z250) was placed incrementally and light-cured. The bonded specimens were sectioned with low-speed diamond saw to obtain $1\times1mm$ sticks after 24 hours of storage at $37^{\circ}C$ distilled water and proceeded thermocycling at the pre-determined cycles of 0, 1,000 and 2,000. The ${\mu}TBS$ test was carried out with EZ-tester at 1mm/min. The results of bond strength test were statistically analyzed using one-way ANOVA/ Duncan's test at the a < 0.05 confidence level. Also, the fracture mode of debonded surface and the interface were examined under SEM. The results of this study were as follows ; 1. 3-step total etching adhesives showed stable, but bond strength of 2-step adhesives were decreased as thermocycling stress. 2. SE showed the highest bond strength, but single step adhesives (PL, XE) had the lowest value both before and after thermocycling. 3 Most of adhesives showed adhesive failure. The total-etching systems were prone to adhesive failure and the single-step systems were mixed failure after thermocycling. Within limited results of this study, the bond strength of adhesive system was material specific and the bonding durability was affected by the bonding step/ procedure of adhesive Simplified bonding procedures do not necessarily imply improved bonding performance.

• Radiation Oncology Journal
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• v.14 no.3
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• pp.221-228
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• 1996

Purpose : We tried to evaluate the clinical characteristics, the treatment methods, the results of treatments, and the Patterns of failure in ovarian dysgerminoma retrospectively According to the results we would like to suggest the proper management guideline of stage la ovarian dysgerminoma patients who want to maintain fertility. Materials and Methods : Between 1975 and 1990, 34 patients with ovarian dysgerminoma were treated at the Yonsei University Hospital. The case records of these patients have been reviewed for presenting symptoms, treatment methods, local control and survival following treatment. Excluded from analysis were five patients with mixed ovarian germ cell tumors and gonadoblastomas (46,XY) Treatment results of the twenty nine patients were analysed by each treatment modality. Twenty one patients were treated with surgery and postoperative adjuvant radiotherapy (group 2). The other eight patients were treated with operation alone (group 2). The median age of twenty-nine patients was 23 years with a range of 8 to 39 years. Presenting symptoms were abdominal mass (20) pelvic discomfort or pain (5) et al. Radiotherapy was performed by 10MV LINAC or Co-60 teletherapy unit. The total radiation dose of the whole abdomen was 20-25 Gy/3weeks, 1-1.5 Gy/fraction with a boost to the whole pelvis 10-15 Gy/l-2weeks 1.8-2.0 Gy/fraction. Advanced stage disease (stage II or stage III) patients received prophylactic mediastinal and supraclavicular irradiation to a dose of 16-26 Gy. Median duration of follow-up of living patients was 80 months (range 13-201 months). Results : All of the twenty one patients of group 1 were alive without disease ($100\%$). Among the eight patients who were not treated with radiotherapy (group 2), six patients developed local recurrence. Four Patients referred with recurrent disease were treated with salvage radiotherapy. Three of four patients were salvaged and one Patient who had recurrent intra-abdominal disease died of progressed carcinomatosis at 11 months after salvage radiotherapy. The other two patients with recurrence were salvaged with chemotherapy (1 patient) or re-operation (1 Patient). Twenty eight patients remained alive without disease at last follow up, so the 5 year local control rate and 5 year overall survival rate for all groups were $96.6\%$ (28/29), respectively. Among thirteen patients with stage la unilateral tumors seven patients were treated with postoperative radiotherapy and the other six patients were treated with unilateral salpingo-oophorectomy alone. Five patients who did not received radiotherapy developed local failure but all of the recurrent ovarian dysgerminomas were salvaged with radiotherapy, chemotherapy or re-operation. So all the 13 patients with stage la ovarian dysgerminoma were free of disease from 20-201 months (median 80 months). Conclusion : The authors consider external irradiation to be an effective treatment as a complement to surgery in ovarian dysgerminoma. For those patients with disease presenting in stage la tumors who wish to maintain fertility, unilateral salpingo-oophorectomy alone may be curative and spare ovarian function considering excellent salvage rate of recurrent ovarian dysgerminoma in present study.

• Journal of East-West Nursing Research
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• v.13 no.2
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• pp.160-169
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• 2007

Background: Hwa-Byung is known as a specific Korean cultural syndrome which corresponds to DSM-IV(MMPI). Some Korean women who have experienced heart aching anger(Hwa-Byung) complain physical pains as well as psychological problems. As for these physical pains, upper limb arthropathy(e.g. golf elbow pains, tennis elbow pains, or shoulder-joint pains) have not been paid attentions. In spite of not having done her excessive physical endeavor or exercise, some Korean middle aged women complain those arthropathy pains. And they go round orthopedics, pain clinics, and oriental medicine clinics. Purpose: This study was practiced in Severance Oriental Medicine Clinic. The oriental medicine doctor had a question about the major origin of upper limb pains which were not caused by excessive physical endeavor. To answer the question, this study has been practiced. In the process of interview with some those women, the major cause of those syndromes has been revealed as Hwa-Byung. The purpose of this study is to discover the meanings of the women's life who have been experienced Hwa-Byung with upper limb arthropathy. Results: These upper limb arthropathy can be explained by meridian theory. Shoulder-joint pain and golf elbow with Hwabyung can be explained by Heart meridian of hand-shoyin and the points of these pains are in the flow of this meridian. Tennis elbow with Hwabyung can be explained by Small intestine meridian of hand-taiyang and this point is in the flow of this meridian. The results of interview with 9 middle aged women was analyzed and interpreted according to Spradley's method of ethnography. The analysis revealed three core cultural themes : 1) There are certainly external cause to provoke Hwa-Byung. A patricentric family system, husband's playing around with another woman, cruel treatment by husband's family, or financial failure may be present anteriorly. 2) The chief existing condition is the discord between husband and wife. The stoppage of mutual communication, lacking in understanding, unfeeling, heartless, or unsympathetic is an major phenomenon of married life. So the important factor is not the sexual relations or problems but the discords of communication. 3) The feeling of anger, the sense of nihility, the desire to escape, and the effort to forgiveness coexist together. At a glance, they seemed to be a process. For example, anger seemed to present at first, then nihility seemed at second, then escape seemed at third, and then forgiveness seemed at last. But at point of visiting clinic to be treated, they are mixed up together as if in a jumble.

• Composites Research
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• v.30 no.5
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• pp.316-322
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• 2017

Carbon fiber is a material with excellent mechanical, electrical and thermal properties, which is widely used as a composite material made of a polymer matrix. However, this composite material has a weak point of interlaminar delamination due to weak interfacial bond with polymer matrix compared with high strength and elasticity of carbon fiber. In order to solve this problem, it is essential to use reinforcements. Due to excellent mechanical properties, graphene have been expected to have large improvement in physical properties as a reinforcing material. However, the aggregation of graphene and the weak interfacial bonding have resulted in failure to properly implement reinforcement effect. In order to solve this problems, dispersibility will be improved. In this study, functionalization of graphene nanoplatelet was proceeded with melamine and mixed with epoxy polymer matrix. The carbon fiber reinforced polymer composites were fabricated using the prepared graphene nanoplatelet/epoxy and flexural properties and interlaminar shear strength were measured. As a result, it was confirmed that the dispersibility of graphene nanoplatelet was improved and the mechanical properties of the composite material were increased.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.2
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• pp.170-178
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• 2015

In this study, it was developed eco-friendly alkali-activated slag fiber reinforced concrete using ground granulated blast furnace slag, alkali activator (water glass, sodium hydroxides), and steel fiber. Eight reinforced concrete beam using alkali-activated slag concrete were constructed and tested under monotonic loading. The major variables were mixture ratio of alkali activator, mixed/without of steel fiber. Experimental programs were carried out to improve and evaluate the flexural performance of such test specimens, such as the load-displacement, the failure mode, the maximum load carrying capacity, and ductility capacity. All the specimens were modeled in scale-down size. The reinforced concrete beams using the eco-friendly alkali-activated slag fiber reinforced concrete was failed by the flexure or flexure-shear in general. In addition, the maximum strength increased with the adding the mol of sodium hydroxide, and the specimen reinforced the steel fiber showed the value of maximum strength which is increased by 15.8% through 25.9%. It is thought that eco-friendly alkali-activated slag fiber reinforced concrete can be used with construction material and product to replace normal concrete. If there is applied to structures such as precast concrete member and production of 2nd concrete product, it could be improved the productivity and reduction of construction duration etc.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.5
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• pp.284-293
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• 2013

Purpose: For reconstruction of craniomaxillofacial defects caused by tumor, trauma, infection etc, free flap transplantation with microvascular surgery is a very useful method. Thrombus formation at the anastomosis site is the major cause of graft failure. 4-Hexylresorcinol (4-HR) is generally known as an antiseptic and antiparasitic agent. This study was conducted in order to evaluate the effect of 4-HR on blood coagulation in vitro. In addition, we investigated thrombus formation and endothelial repair of an injured vessel in an animal model. Methods: In the in vitro experiment, we compared blood coagulation time between the 4-HR treated group and normal blood. Thirty rats were used for in vivo animal experiments. After exposure of the right femoral vein, a micro vessel clamp was placed and the femoral vein was intentionally cut. Microvascular anastomosis was performed on all rats using 10-0 nylon under microscopy. The animals were divided into two groups. In the experimental group (n=15), 4-HR (250 mg/kg) mixed with olive oil (10 mL/kg) was administered per os daily. Animals in the control group (n=15) were given olive oil only. The animals were sacrificed at three days, seven days, and fourteen days after surgery and rat femoral vein samples were taken. Vascular patency and thrombus formation were investigated just before sacrifice. Histologic analysis was performed under a microscope. Results: Results of an in vitro blood coagulation test showed that coagulation time was delayed in the 4-HR treated group. The results obtained from an in vivo 4-HR administered rat model showed that the patency of all experimental groups was better at thirty minutes, seven days, and fourteen days after microvascular anastomosis than that of the control group at seven and fourteen days after anastomosis, and the amount of thrombus in the experimental groups was much less than that of the control group. Endothelial repair was observed in the histologic analysis. Conclusion: Findings of this study demonstrated that blood coagulation was delayed in the vitro 4-HR treated group. In addition, good vascular patency, anti-thrombotic effect, and repair of venous endothelial cells were observed in the vivo 4-HR administered rat group.

• Clinical and Experimental Pediatrics
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• v.51 no.3
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• pp.329-334
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• 2008

Kwashiorkor is a syndrome of severe protein malnutrition, which manifests itself in hypoalbuminemia, diarrhea, dermatitis, and edema. It can be life-threatening due to associated immune deficiency and an increased susceptibility to infections. Kwashiorkor should be treated early with nutritional support and the control of infection. Dilated cardiomyopathy may develop during the treatment and in such cases a poor prognosis is expected. Kwashiorkor has been known as a common disease of poor countries. To date, in fact, there has been no report of kwashiorkor leading to death in technically advanced countries. We here report a fatal case of a baby girl admitted with kwashiorkor. She had been fed only with cereal grain mixed with juice, without any protein supplement, for 2 months. This diet was deficient not because of poverty, but due to the illiteracy of her parents. The patient suffered from diarrhea, whole body edema, hypothermia, and dermatitis. Laboratory findings revealed an immune-deficient state featuring leukopenia and decreased immunoglobulin. Blood and urine cultures revealed Alcaligenes Xylosoxidans growth. The patient was fed frequent small amounts of protein-containing formula and intravenous albumin and micronutrients were administered for nutritional support. She was also treated with intravenous immunoglobulin and antibiotics in order to control infection. Nevertheless, she developed dilated cardiomyopathy and multi-organ failure and died. We review this case in light of the literature.

• The Journal of the Korea Contents Association
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• v.18 no.9
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• pp.44-54
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• 2018

In the construction project, the design field has a crucial effect on the success or failure of the final product, and it is becoming more important as a core area of national industrial development because it creates high value added by technology. In addition, since the design work is carried out based on professional technical personnel, in order to secure the quality and competitiveness of the design, it is necessary to continuously input the excellent manpower and develop the technology, and above all, the appropriate design cost must be ensured. However, as a result of reviewing the current status of the design cost criterion in Korea, problems such as mixed cost calculation method, inaccuracy of construction cost ratio method, and inactivation of cost plus fixed fee method were analyzed. Therefore, it is difficult to calculate the fair value reflecting the characteristics of the project when calculating the construction design price. Therefore, the price criterion should be improved so that the fair value of the design can be determined according to the contents of the project, By analyzing the correlation and multiple regression analysis of the projects and price information of the completed road construction design, the factors influencing the design price and the level of influence were analyzed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.146-152
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• 2018

In this study, to improve the performance of asphalt mixtures for plastic deformation occurring mainly in Korea, complex modifiers were prepared by mixing powders and liquid type modifiers. The main constituents were powdery diatomaceous earth, mica and carbon black, and liquid type solid 70% SBR latex. The tensile strength ratios for the two asphalt mixtures used in the test were above 0.80 for the Ministry of Land Transportation (2017) asphalt mixture production and construction guidelines. The effects of increasing the tensile strength in the dry state was more than 14% when the composite modifier was added. The deformation rate per minute by the wheel tracking test load was an average of 0.07 to 0.147 for each mixture. The strain rate per minute was improved by the modifier, and the dynamic stability was improved by almost 100% from 295 to 590. In addition, the final settling was reduced from 11.38 mm to 9.57 mm. A plastic deformation test using the triaxial compression test showed that the amount of deformation entering the plastic deformation failure zone at the end of the second stage section and in the third stage plastic deformation section was 1.76 mm for the conventional mixture and 1.50 mm for the complex modifier mixture. The average slope of the complex modifier asphalt mixture mixed with the multi-functional modifier was 0.005 mm/sec. The plastic deformation rate is relatively small in the section where the road pavement exhibits stable common performance, i.e. the traffic load.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.1
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• pp.39-43
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• 2003

Dietary fatty acid including mainly palmitic acid and stearic acid was fed to fattening cattle and its effect on body weight gain, plasma lipid contents and rumen liquid fermentation in vitro was examined. In expt. 1, the effect of dietary fatty acid on body weight gain and plasma lipid concentrations was examined. In the control diet group, cattle were fed 1 kg/day of rice straw and concentrate which satisfied the requirement. In the fatty acid group, cattle were given 250 g/d of fatty acid with the same diet of the control diet group. In the excess concentrate group, cattle were given the same diet of the control diet group plus 735 g/d of concentrate corresponding to the same TDN of 250 g/d of fatty acid. Diets were given for 7 days. Body weight gain of cattle given dietary fatty acid was significantly greater than that of cattle fed only rice straw and concentrate. When dietary fatty acid was added to cattle feed, plasma NEFA and HDL-cholesterol concentrations increased. In expt. 2, the influence of dietary fatty acid on gas production and VFA profile in the rumen liquid was investigated in vitro. In the control group, 10 mg of rice straw and 90 mg of concentrate were incubated in the rumen fluid. In the excess concentrate group, 10 mg of rice straw and 97.5 mg of concentrate were incubated. In the fatty acid group, 10 mg of rice straw, 90 mg of concentrate and 2.5 mg of fatty acids were incubated. The rumen liquid mixed with feed materials was incubated for 24 h and the cumulative gas volume was measured. The VFA profile was also measured. Cumulative gas volume in the rumen liquid with fatty acid was equal to the control. Excess concentrate increased cumulative gas volume compared to the fatty acid group. There was no significant difference in total VFA concentration between experimental diet groups. It is suggested that dietary fatty acid has the potency to improve growth performance in fattening cattle without failure in rumen fermentation.