• Title/Summary/Keyword: enhancement factor

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A STUDY OF REGENERATION ENHANCEMENT OF DESTRUCTED PERIODONTAL TISSUE (파괴된 치주조직의 재생촉진에 관한 연구)

  • Han, Kyung-Yoon
    • Journal of Periodontal and Implant Science
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    • v.25 no.2
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    • pp.407-417
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    • 1995
  • In order to evaluate the effect of platelet-derived growth factor(PDGF-BB) and guided tissue regeneration(GTR) technique on the regeneration of destructed periodontal tissue,intentional through-and-through furcation defects(4mm in height) were made on both mandibular 2nd and 4th premolars of 8 adult male dogs(30-40lb). Experimental group 1 was composed of the premolars that were treated by only topical application of PDGF-BB with 0.05M acetic acid without any barrier membrane. Experimental group 2 was composed of the premolars that were treated by GTR with expanded polytetrafluoroethylene membrane(ePTFE : Gore-tex periodontal material, USA). Experimental group 3 was composed of the premolars that were treated by GTR with ePTFE after topical application of PDGFBE. Control group was composed of the premolars that were treated by coronally positioned flap operation only without use of PDGF-BB and ePTFE membrane. All ePTFE membranes were carefully removed 4 weeks after regenerative surgery, and all experimental animals were sacrificed 8 weeks after regenerative surgery. The light microscopic findings were as follows ; (1) In experimental group 1, rapid new bone formation along the-root surface with multiple ankylosis and root resorption by multinucleated giant cells, and dense connective tissue in the central portion of the furcation defects were observed. (2) In experimental group 2, it was observed that the furcation defects were filled with newly formed bone, Sharpey's fibers were embedded into new cementum on root dentin of furcation fornix area, but the central portion and the area under furcation fornix were still filled with dense connective tissue. (3) In experimental group 3, the furcation defects were regenerated with newly formed dense bone and regular periodontal ligament with Sharpey's fibers embedded into newly formed cementum and bone underneath fornix area. (4) In control group, unoccupied space, apical migration of epithelium, dense infiltration of inflammatory cells in subepithelial connective tissue in relation to heavy plaque accumulation, and root resorption by inflammatory reaction were shown, but any new cementum formation on resorbed dentin surface could not be observed. The present study demonstrated that the combined therapy of PDGF-BB and GTR could enhance the regeneration of destructed periodontal tissue.

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A Case of Spindle Cell Hemangioendothelioma Involving the Lung, Mediastinum and Brain (폐, 종격동 및 뇌를 침범한 방추세포형 혈관내피종 1예)

  • Kim, Hwan-Tae;Kim, In-Ho;Lee, Bong-Choon;Kang, Chang-Il;Yoon, Hye-Kyoung
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.3
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    • pp.301-307
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    • 1993
  • Intravascular bronchioloalveolar tumor is now recognized as a pulmonary form of hemangioendothelioma(HE). HE is an unusual tumor of adult life which is characterized by proliferation of an "epithelioid" or "spindle" endothelial cell. In the lung it usually presents as multiple bilateral slowly growing nodules less than 2 cm in diameter. The aetiology and pathogenesis of this disease are unknown. Spindle cell HE occurs at any age, but approximately one half of patient are 25 years of age or younger and males are affected twice more frequently than females. On light microscopic examination, the tumor show mild cellular atypia, nearly absent mitoses and electron-microscopic studies reveal evidence of endothelial cell differentiation. Intracytoplasmic localization of Factor VIII-related antigen is demonstrated on immunohistochemical study, which confirmed the endothelial origin of the tumor. No effective therapy is yet known for HE, but survival of this tumor can be quite long. However, one half of the patient have died, usually of progressive pulmonary insufficiency. This 19-yr-old male complained of Rt. chest pain and intermittent hemoptysis. Simple chest film and chest CT scan showed the Rt. pleural effusion, variable sized bilateral pulmonary nodules, irregular large heterogenous tumor with well enhancement and extensive necrosis in the anterior mediastinum. The mediastinal mass was biopsied and diagnosed as spindle cell HE by light microscopic finding and immunohistochemical studies.

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Analysis of Cylinder Swirl Flow and Lean Combustion Characteristics of 3rd Generation LPLI(Liquid Phase LPG Injection) Engine (제3세대 LPLI 엔진 연소실내 스월유동 및 희박연소 특성 해석)

  • Kang, Kern-Yong;Lee, Jin-Wook
    • Journal of Advanced Marine Engineering and Technology
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    • v.31 no.1
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    • pp.26-33
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    • 2007
  • The intake swirl motion, as one of dominant effects for an engine combustion. is very effective for turbulence enhancement during the compression process in the cylinder of 2-valve engine. Because the combustion flame speed is determined by the turbulence that is mainly generated from the mean flow of the charge air motion in intake port system. This paper describes the experimental results of swirl flow and combustion characteristics by using the oil spot method and back-scattering Laser Doppler velocimeter (LDV) in 2-valve single cylinder transparent LPG engine using the liquid phase LPG injection. For this. various intake port configurations were developed by using the flow box system and swirl ratios for different intake port configurations were determined by impulse swirl meter in a steady flow rig test. And the effects of intake swirl ratio on combustion characteristics in an LPG engine were analyzed with some analysis parameters that is swirl ratio. mean flow coefficient, swirl mean velocity fuel conversion efficiency. combustion duration and cyclic variations of indicated mean effective pressure(IMEP). As these research results, we found that the intake port configuration with swirl ratio of 2.0 that has a reasonable lean combustion stability is very suitable to an $11{\ell}$ heavy-duty LPG engine with liquid phase fuel injection system. It also has a better mean flow coefficient of 0.34 to develope a stable flame kernel and to produce high performance. This research expects to clarify major factor that effects on the design of intake port efficiently with the optimized swirl ratio for the heavy duty LPG engine.

Employment and Married Women's Health in Korea; Beneficial or Harmful? (기혼 여성의 직업이 신체적, 정신적 건강에 미치는 영향)

  • Kim, Il-Ho;Chun, Hee-Ran
    • Journal of Preventive Medicine and Public Health
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    • v.42 no.5
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    • pp.323-330
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    • 2009
  • Objectives : The aim of this study was to investigate whether working married women in different occupational classes affected diverse health outcomes. Methods : We used data for married women aged 25-59 (N=2,273) from the 2005 National Health and Nutritional Examination Survey. Outcome measures included physical/mental and subjective/objective indicators (selfrated poor health, chronic diseases, depression, and suicidal ideation from reported results; metabolic syndrome dyslipidemia from health examination results). Agestandardized prevalence and logistic regression were employed to assess health status according to three types working groups (housewives, married women in manual jobs, married women in non-manual jobs). Sociodemographic factors (age, numbers of children under 7, education, household income) and health behaviors (health examination, sleep, rest, exercise, smoking, drinking) and a psychological factor (stress) were considered as covariates. Results : Non-manual married female workers in Korea showed better health status in all five health outcomes than housewives. The positive health effect for the non-manual group persisted in absolute (age-adjusted prevalence) and relative (odds ratio) measures, but multivariate analyses showed an insignificant association of the non-manual group with dyslipidemia. Manual female workers showed significantly higher age-adjusted prevalence of almost all health outcomes than housewives except chronic disease, but the associations disappeared after further adjustment for covariates regarding sleep, rest, and stress. Conclusions : Our results suggest that examining the health impact of work on married women requires the consideration of occupational class.

Effects of Electrochemical Oxidation of Carbon Fibers on Mechanical Interfacial Properties of Carbon Fibers-reinforced Polarized-Polypropylene Matrix Composites (전기화학적 산화처리가 탄소섬유/극성화된 폴리프로필렌 복합재의 기계적 계면 특성에 미치는 영향)

  • Kim, Hyun-Il;Choi, Woong-Ki;Oh, Sang-Yub;An, Kay-Hyeok;Kim, Byung-Joo
    • Applied Chemistry for Engineering
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    • v.24 no.5
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    • pp.476-482
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    • 2013
  • In this work, the effects of electrochemical oxidation of carbon fiber surfaces on mechanical interfacial properties of carbon fibers-reinforced polarized-polypropylene matrix composites were studied with various current densities during the treatments. Surface properties of the fibers before and after treatments were observed by SEM, AFM, XPS, and contact angle measurements. Mechanical interfacial properties of the composites were measured in terms of critical stress intensity factor ($K_{IC}$). From the results it was found that $O_{1s}$ peaks of the fiber surfaces were strengthened after electrochemical oxidation which led to the enhancement of surface free energy of the fiber, resulting in good mechanical performance of the composites. It can be concluded that electrochemical oxidation of the carbon fiber surfaces can control the interfacial adhesion between the carbon fibers and polarized-polypropylene in this composites system.

Attitude toward One's Own Aging among Korean Middle-aged Adults and the Elderly (중장년 성인과 노인의 노화에 대한 태도)

  • Jo, Ahra;Oh, Heeyoung
    • Korean Journal of Adult Nursing
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    • v.29 no.1
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    • pp.41-50
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    • 2017
  • Purpose: The purpose of this study was to identify and compare the factors influencing attitude toward one's own aging among Korean middle-aged adults and the elderly. Methods: A cross sectional study was performed with a total sample of 70 middle-aged adults and 64 elderly reside in two metropolitan areas. Data were collected from August 2015 to November 2015 using the Perceived Health Status Scale, the Health Locus of Control Scale and the Attitude Toward own Aging (ATOA) Scale. The statistics used include percentage, t-test, Pearson's correlation coefficient, and multiple regression. Results: Mean age for each age group were about 52 and 76 years old for middle-aged adults and the elderly respectively. A considerable proportion of all participants reported a negative attitude toward aging. Perceived health status was the common factor influencing attitude toward one's own aging in both age groups. Middle-aged adults identified presence of chronic illness and internal health locus of control as important factors. In contrast, the elderly reported that education and others-dependent health locus of control such as powerful others had a significant impact on ATOA. Each regression model explained 31% and 55% of the total variance of ATOA among middle-aged adults and among the elderly. Conclusion: Both middle-aged adults and the elderly with low perceived health status are at risk of negative ATOA's. The type health locus of control need to be identified and utilized based on individuals' tendency to improve positive ATOA. That is, middle-aged adults might need reinforcement of their self-will whereas the elderly might need enhancement of social support and network of family and healthcare providers.

The Effect of Medium on the α -Effect: Nucleophilic Substitution Reaction of p-Nitrothenyl Diphenyl Phosphinate with Butane-2,3-dione Monoximate and Substituted Phenoxides in Cationic Micelles

  • Limb, Jin-Kyung;Jeon, Sang-Eun;Lee, Seung-Eun;Um, Ik-Hwan
    • Bulletin of the Korean Chemical Society
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    • v.23 no.9
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    • pp.1263-1307
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    • 2002
  • Pseudo-first-order rate constants (kobs) have been determined for the nucleophilic substitution reactions of p-nitrophenyl diphenyl phosphinate (PNPDPP) with substituted phenoxides (XC6H4O - ) and butane-2,3-dione monoximate (Ox- ) in 0.1 M borate buffer (pH = 10.0) at 25.0 ${\pm}0.1^{\circ}C$. The kobs value increases sharply upon addition of cethyltrimethylammonium bromide (CTAB) to the reaction medium up to near 7 ${\times}$ 10-4 M CTAB and then decreases smoothly upon further addition of CTAB. The rate enhancement upon the addition of CTAB is most significant for the reaction with -O2CC6H4O- and least significant for the one with C6H5O- , indicating that the reactivity of these aryloxides in the presence of CTAB cannot be determined by the basicity alone. The strength of the interaction of these anionic aryloxides with the positively charged micellar aggregates has been suggested to be an important factor to determine the reactivity in the presence of CTAB. The kobs value for the reaction with Ox- increases also upon the addition of CTAB. However, the increase in the kobs value is much more significant for the reaction with Ox- than for the one with ClC6H4O- , indicating that Ox- is less strongly solvated than ClC6H4O- in H2O. The ${\alpha}-effect$ shown by Ox- in H2O has been attributed to the ground-state solvation difference between Ox- and ClC6H4O- .

The Design of Compact and wideband antenna for wireless LAN at 5GHz band (5GHz대역 무선랜용 소형 광대역 안테나 설계)

  • Park Kyoung-Su;Choi Sung-Youl;Shin Phil-Soo;Ko Young-Ho
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.41 no.6 s.324
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    • pp.93-99
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    • 2004
  • According to rapid increment of demand for wireless Local Area Network (LAN), the HyperLAN of 5.1-533GHz and 5.725-5.825GHz is newly allocated for wireless LAM in many regions over the world. Also, because most of mobile communication equipments are small, the size of antenna is important factor of effective design. In this paper, the compacted and wide bandwidth antenna is designed for wireless LAN at 5GHz band. Although the structure of U-shaped slot antenna is simple, It has large bandwidth of $10-40\%$. Also, the U-slot antenna has good radiation pattern. However, in general, the size of U-slot antenna is large. Therefore, it is difficult to apply to wireless equipment such as PDA and Notebook. This proposed antenna has a wide bandwidth by U-shaped slot in rectangular patch and is compacted by using two layered dielectric substrates and foam. For the design of U-slot antenna, the Finite Difference Time Domain method is applied. Also, the method of MPI parallel program is used for the enhancement of the analyzing speed of the FDTD method.

A Study on Development of Fashion Orientation Scale for the On-line Image Consulting of Career Men (직장남성의 이미지 컨설팅을 위한 측정도구 개발에 관한 연구 -패션성향을 중심으로-)

  • No Ji Young;Koh Ae Ran;Chung Mi Sil
    • Journal of the Korean Society of Clothing and Textiles
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    • v.29 no.1 s.139
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    • pp.58-67
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    • 2005
  • This study was aimed at the development of scales measuring appearance management behaviors of career men for on-line image consulting. The purposes of this study were to develop a scale which can measure fashion orientation of career men and classify them according to fashion orientation. The data were collected from 380 career men for the first survey and 372 career men for the second survey in Seoul, Korea and were analyzed by factor analysis, reliability test, cluster analysis, one-way ANOVA and Duncan test. The results from this study were as follows: 1) Ten factors of fashion orientation were identified: clothing interest, satisfaction in clothing-selecting ability, individuality and self expression, interest in appearance management, appearance improvement and mood enhancement, clothing conformity, putting value on attractive appearance, maintenance of neat appearance, weight control and pursuit of fashion. The total variance explained by the ten factors was $65.70\%$ and Cronbach's $\alpha$ of 10 factors ranged from $.60\~.92.$ 2) Three groups were classified by the representative items of fashion orientation factors : passive appearance management group who were conscious of other people, positive appearance management group who were highly fashion-oriented and indifferent group to appearance management. The fashion orientation characteristics of groups classified in the second survey were nearly similar to those in the first.

Immuno-Modulatory Effects of Bacteriocin-Producing Pediococcus pentosaceus JWS 939 in Mice

  • Choi, Hyun-Jong;Kim, Ji-Ye;Shin, Myeong-Su;Lee, Sang-Myeong;Lee, Wan-Kyu
    • Food Science of Animal Resources
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    • v.31 no.5
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    • pp.719-726
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    • 2011
  • Pediococcus pentosaceus JWS 939 (JWS 939) is a nonpathogenic bacteriocin-producing probiotic isolated from the duck intestine. This study assessed the immunomodulatory effects of JWS 939 and compared them with those of Lactobacillus rhamnosus GG (LGG), a well-known immune enhancer. The immune-enhancing effects of JWS 939 were measured by measuring the production of nitric oxide (NO) and cytokines in C57BL/6 mouse peritoneal macrophages. In addition, to assess the immune enhancement abilities of JWS 939, in vivo, a Listeria monocytogenes challenge mice model was used. The results showed that heat-killed JWS 939 induced more NO and interleukin (IL)-$1{\beta}$ production in mouse peritoneal macrophages than in LGG, and that oral administration of viable JWS 939 in mice increased more NO, IL-$1{\beta}$, and tumor necrosis factor (TNF)-${\alpha}$ level than in LGG in serum upon L. monocytogenes challenge. In addition, mice fed with JWS 939 had a longer survival time after lethal challenge with L. monocytogenes, and these effects were stronger than those induced by LGG. Collectively, P. pentosaceus JWS 939 is a remarkable strain that, by releasing bacteriocin and enhancing host immune responses, may have potential as a duck feed additive to suppress pathogens.