• Journal of Biomedical Engineering Research
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• v.23 no.2
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• pp.139-145
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• 2002

Bis-GMA, 2.2-bis[p(2-hydroxy-3-methacryloyloxypropokyl)phenyl]Propane, is an essential component as a multifunctional methacrylate prepolymer in the light-curable polymeric dental composite resins. Two hydroxyl groups of the Bis-GMA molecule are considered to induce water sorption of the photocured composite resin in a mouth, resulting in gradual long-term deterioration of aesthetics and mechanical properties of the composite resins. In this study, some additives such as light stabilizer and antioxidant were added to composite resins to promote durability and storage stability of the last product. First of all, color change increased as a light stabilizer. Tinuvin P, was added to the composed resins and color stability was improved as an antioxidant, Irganox 245, was added to ones. In addition, when Tinuvin P and Irganox 245 were added together to the composed resins. the color stability was enhanced and mechanical properties such as diametral tensile strength before and after acceleration tests were also not greatly decreased. Therefore, when 0.5 weight Percent of Tinuvin P and 0.1 weight percent of Irganox 245 were added together to dental composite resins. the durability and color stability were enhanced, and furthermore the storage stability was also improved for the composed resins.

• Journal of Preventive Medicine and Public Health
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• v.36 no.2
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• pp.101-107
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• 2003

Objectives : Dementia has emerged as a leading public health problem in elderly persons, and its early detection is important for the treatment of curable cases, and in the educational support for other family members. Although dementia screening tests are available, they have not gained widespread use in community or primary care settings. Our goal was to validate the Tine and Change (T&C) Test, -including its validity and reliability in patients, and to assess it as a simple, standardized method for the screening of dementia in the rural elderly. Methods : The participants in this study comprised of 59 patients from an urban hospital and 405 persons from a rural community aged 65 years or older. The time test evaluated the understanding of clock hands indicating 11:10, and the change test the ability to make 1,000 Won from a group of coins, consisting of one 500, seven 100, and seven 50 Won coins. The T&C ratings were validated against a reference standard based on the physician's diagnosis of the patients. The convergent validity in relation to other cognitive measure, test-retest agreement, and inter-observer reliability were assessed. To assess the relationship between the Korean Mini-Mental State Exam (K-MMSE) and the T&C Test, the mean K-MMSE scores were compared with the results of the T&C Test in the elderly from a rural community. Results The T&C Test had a sensitivity and specificity of 73.0, and 90.9%, and positive and negative predictive values of 93.1, and 66.7%, respectively. The test-retest and inter-observer agreement rates were both 95%. The K-MMSE scores and T&C Test were significantly related in the elderly from a rural community (p<0.01), The T&C Test was not influenced by the educational status. The Time and Change Tests took a mean of 6.3 and 12.7 seconds, respectively, to complete Conclusion : The T&C Test is a simple, accurate and reliable, performance-based tool in the screening for dementia. Because it is quick, and easy-to-use, it is hoped the T&C Test will be used for the widespread cognitive screening of aging populations.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.5
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• pp.475-479
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• 2012

We present a novel polymer fabrication process involving direct UV patterning of a hyperbranched polymer, AEO3000. Compared to PDMS, which is the most widely used polymer in bioMEMS devices, the present polymer has advantages with regard to electrode integration and fast fabrication. We designed a four-chip microelectrofluidic bench having three electrical pads and two fluidic I/O ports. We integrated a microfluidic mixer and a cell separator on the bench to characterize the interconnection performance and sample manipulation. Electrical and fluidic characterization of the microfluidic bench was performed. The measured electrical contact resistance was $0.75{\pm}0.44{\Omega}$, which is small enough for electrical applications, and the pressure drop was 8.3 kPa, which was 39.3% of the value in the tubing method. By performing yeast mixing and a separation test in the integrated module on the bench, we successfully showed that the interconnected chips could be used for bio-sample manipulation.

• Korean Journal of Head & Neck Oncology
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• v.17 no.1
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• pp.59-62
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• 2001

Objectives: We report an interim result of conformal radiotherapy in a patient with early stage cancer at the base of the tongue, which developed in a previously irradiated area. Materials and Methods: A 64-year-old male patient was diagnosed with T4N0M0 supraglottic cancer. He received 72Gy of radiation therapy from 21 November 1988 to 24 February 1989. He had local failure and underwent a salvage total laryngectomy on 28 August 1989. Subsequently, he did well. In early 1999, he suffered from throat pain. He had a 2.5cm ulcerative mass at the base of his tongue, in the area that had been irradiated previously. Biopsy showed squamous cell carcinoma. After workup, he was diagnosed with base of tongue cancer with T2N0M0. Surgery was not feasible because the morbidity was not acceptable. Since it was difficult to re-irradiate the area with a curable dose using conventional 2D radiation therapy with an acceptable morbidity, we decided to try conformal radiotherapy. We used 7 static beam ports with field sizes from $7x6.4\;to\;8x8cm^2$, using 6 and 10MV photons. The fractionation regimen was 1.8Gy, 5 times per week. He received 64.8Gy in 36 fractions from 9 April 1999 to 1 June 1999. Results: In the 21 months since radiotherapy, the patient has not experienced any acute or chronic complications, such as xerostomia. He experienced relief of pain shortly after the start of radiotherapy, showed a complete response, and is still doing well. Conclusion: Conformal radiotherapy can be used to treat cancer that develops within a previously irradiated field, with curative intent.

• Journal of Pharmacopuncture
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• v.21 no.3
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• pp.139-150
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• 2018

Averagely 80% to 90% of breastfeeding women experience the nipple pain and fissures. The important factor for successful breastfeeding is to treat this problem. This study has done as a review with the aim of analysis of the clinical trials in the field of the prevention and treatment of the nipple fissures and pain due to the importance of breastfeeding. For this purpose, the key words of sore, nipples, fissure, trauma, wound, prevention, treatment, therapeutics, therapy, clinical trial, breastfeeding and their Persian synonyms and all of their possible combinations were searched in the national databases: SID and Iran Medex and Magiran, and in the international databases: PubMed, Scopus, Medline, Science direct by May 2017. The Jadad criterion was used to assess the quality of the articles and the articles with a score of 3 or more were included in this study. Finally, 48 clinical trials were reviewed that 17 of them (sample size 1801) scored 3 or more based on the Jadad criterion. Seven articles were also in the non- drug treatment group (sample size 491) and 2 articles in the drug treatment group (sample size 337) and 8 articles in the herbal treatment group (sample size 973).The results show that menthol and warm water compress as well as teaching the correct breastfeeding methods are effective treatments to prevent and treat the nipple pain and fissures. Moreover, applying the herbal medicine for prevention and treatment of the issues raised from breastfeeding may have beneficial such as Aloe vera, Portulaca olearacea. However, more studies with a great methodology are necessary to obtain more accurate evidence.

• The Journal of Korean Medicine
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• v.19 no.1
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• pp.430-443
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• 1998

The research on the actual condition of the oriental health related industry has been made with defining it's phase. As a result, I have come to develope korean-type health model, which can solve the problems derived from the past herb medicine industry. The prospects and roles of the oriental health related industries are as follows: The phase adjustment of the oriental health related industry. The problems of modern medical science happens in the beginning of 21st century, the importance of oriental health improvement in the field of health business is now being on the rise. therefore it is necessary to readjust the present status of the oriental medicine and to take it into health area. Should the responsible institutes regarded on oriental medicine make clear prescription in terms of oriental health industry's role and limitation, they could contribute health circumstance in the 21st century. This is because oriental health related industry can be utiliged in not only protective area and curable area. The present situation of the oriental health related industry. These herb medical societies are flooded with various oriental health industry apart from the legal systematic control so far health industry apart from the legal systematic control so far. The expected survey can not be complete but random under these situations. Nevertheless oriental medical health industry area such as a diet cure, exercise treatment and living condition cure are being considerably expanded, especially living facilities improvement and mind control areas are toward worldwide. Consquently herb health industries are now？ consistantly developed by the influence of western nature treatment stemmed from the oriental medicine theory. The role and prospect of the oriental health related industry in 21st century. The oriental health industries can be helpful for the human being's health improvement in general but by the lack of scholastic oriental health theory, it does not contribute to the health welfare. If these problems are made up for in the field of theory area, the oriental health related industry will surely have the potentiallity and know how for health welfare. The successive role of these industry is depended on the fact that the characteristics of the oriental medicine should adjust to the real society with the systematic management. In the 21C, oriental health industry will certainly be vitalized owing to the social and periodical request especially in the area of oriental medical industry, oriental health drink industry, oriental health mind exercise industry, oriental health leasure industry and oriental health complex management industry. Among these areas, it is the oriental health complex amagement industry that will be the limestone of prosperity of the oriental health industry in 21C. Proposal for the social contribution of the oriental health related industry in the 21C. To achive the ultimate role of the oriental health industry in the 21c, first we should know how to use the oriental medicine. Second We should make an effort to revitalize the oriental health industry. So it is indespensible that government, academic institution and enterprise should concentrate their interest on the oriental health industry with common knowledge and systematic management in advance.

• Restorative Dentistry and Endodontics
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• v.25 no.3
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• pp.421-434
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• 2000

The purpose of this study was to evaluate the influences of incorporation of zirconium-silicate on diametral tensile strength, shear bond strength to the enamel, and depth of cure of 7 experimental composites. One group contained no filler(group 1 or control group), and the other 6 composites contain 75% filler in which zirconium-silicate(Zr-Si) were 0%, 2%, 4%, 6%, 8%, 10% with reduced contents of silica filler, respectively. Both of fillers were treated with 1% silane (${\gamma}$-methacryloxypropyltrimethoxy silane). Light curable monomers were prepared by mixing Bis-GMA and TEGDMA with 3:1 ratio and adding camphoroquinone(CQ) 0.6% with tertiary amine 0.3%. Diametral tensile strengths of specimens with $3mm{\times}6mm$ were measured with Instron (No.4467, USA) with 1mm/min crosshead speed. Shear bond strengths of composites which bonded to bovine enamel etched with 37% phosphoric acid were measured at Instron Testing Machine with as same speed as in diametral tensile strengths. Depth of cure were measured by a method that composite was filled in cylinder mold, illuminated at one side. and uncured composite was removed with acetone, and the residual thickness of composite was measured. Following results were obtained ; 1. Composites containing 0%, 2%, or 4% zirconium-silicate filler(group 2, 3 and 4) showed the statistically higher diametral tensile strength than the others. (p<0.05) 2. Increase of zirconium-silicate filler contents reduced the diametral tensile strength of experimental composites. ($r^2$=0.8721, p=0.0002) 3. Increase of zirconium-silicate filler contents did not affect the shear bond strength of experimental composites. ($r^2$=0.2815, p=0.4067) 4. Increase of zirconium-silicate filler contents reduced significantly the depth of cure of experimental composites. ($r^2$=0.9700, p<0.0001) These results mean that the mechanical properties of composites could not be improved by incorporation of small amount of zirconium-silicate filler. Also, the increased contents of zirconium-silicates fillers was found to reduce the diametral tensile strength and depth of cure.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.4
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• pp.348-354
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• 2015

Urethane waterproofing materials which currently being used most commonly in the Korean domestic market have high applicability and construct layers without forming any joints, but under the influence of low temperature and low humidity, as well as the thickness of the applied layer, the curing time of this material may become extended in construction sites. To resolve these issues, a proposed method of using water-hardening type of polyurethane waterproofing materials are being developed. However, there currently lacks any standards or evaluation methods on determining an optimal mixture ratio of water for the water-hardening polyurethane waterproofing materials. Therefore, workers and construction workers are relying on their hands-on-skills and experience to determine this ratio and are not able to obtain a consistent performance quality out of these materials. Therefore, for the establishment of a board applicability of the water-hardening polyurethane waterproofing methods in construction sites, this study objectively analyzes the changes in the performance of these materials depending on the changes of the water mixture ratio and attempts to procure the optimal ratio on the basis of forming a provisionary standard. The study prepares mixtures of varying ratio(no water added, 5, 10, 15, 20, 25, 30, 40 and 50) and conducts comparative analysis respective mixtures' performances and their changes in the physical properties in an objective manner and proposes a provisional optimal value that can serve as a data base that can be used as a reference for future studies.

• Journal of Adhesion and Interface
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• v.11 no.2
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• pp.50-56
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• 2010

Polyethyleneterephthalate (PET) film is widely used in various industrial fields such as mobile phone, display pannel, notebook etc. Recently PET film attached on indium tin oxide (ITO) surface has a role of high pencil hardness, high refractive index etc. So we synthesized two types of multi-functional monomer which are epoxy modifed acrylate and unmodified acrylate type using recyclable resource like phloroglucinol, derived from trinitrotoluene. We studied the effect of multi-functional monomer's chemical structure on the various properties such as refractive index, optical transmittance, and pencil hardness. We characterized synthesized multi-functional monomer by qualitative analysis through H NMR. We observed that pencil hardness of 1,3,5-triepoxide benzene and 1,3,5-triacrylate benzene they have the range of 2~3 H at high UV dosage of 300 mW. Refractive index appeared the value of 1.54~1.57. Transmittance of all multi-functional monomers has more than 93%.

• Journal of Adhesion and Interface
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• v.18 no.1
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• pp.25-32
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• 2017

For application to display module junction process, the silk screen printing based on UV curable acrylic pressure sensitive adhesive(PSA) with silica nano-particles and the rheological properties were studied to investigate the effect on printability and adhesion. The monomers for PSA were based on 2-ethylhexyl acrylate(2-EHA) and acrylic acid(AA) 93:7, butyl acylate(BA), 2-hydroxyethyl acrylate(2-HEA) and tetrahydrofurfuryl acrylate(THFA) were added. Additionally, hydrophobic and hydrophilic nano-particles AEROSIL R974 and AEROSIL 200 were added, respectively. When the ratio of nano-particle was used above 4 or 7 phr, G' and ${\eta}^*$ were increased significantly. When the ratio of AEROSIL 200 was used above 7 phr, the penetration property was decreased during the silk screen printing. We found that the adhesion was decreased with increasing the nano-particle content, and it was decreased in the case of the hydrophilic nano-particle AEROSIL 200.