• 제목/요약/키워드: Al sample

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임플란트 구성요소의 파절면에 관한 주사전자현미경적 연구 - Part I: 임플란트 고정체 (Fracture Analysis of Implant Components using Scanning Electron Microscope - Part I : Implant Fixture)

  • 임광길;김대곤;조리라;박찬진
    • 구강회복응용과학지
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    • 제26권3호
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    • pp.297-309
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    • 2010
  • 보철물의 실패는 파절로 인해 다수 발생하게 되지만 파절 발생시 그 원인을 파악하는 것은 어렵다. 보철물의 실패를 예방하고 예후를 예측하기 위해 보철물의 원인을 분석하는 것이 중요하며, 원인을 밝히기 위해 파절면 분석을 시행하게 된다. 파절면 분석은 파절면 뿐 아니라 주위 환경(응력 상황)에 대한 분석이 동반되며, 이를 이용하여 균열 진행, 파절 양상, 파절 원인 등을 파악하게 된다. 이 연구의 목적은 임상적으로 기능 후 파절된 임플란트 고정체의 파절면 분석을 시행하여 파절 기전 및 파절 원인(하중 양상)을 밝히는 것이다. 파절된 임플란트 고정체는 3년간 강릉-원주 대학교에 임플란트 고정체의 파절을 주소로 내원한 환자를 대상으로 수집하였다. 먼저 임상 및 방사선 사진 분석을 하였으며, 시편 세척 과정을 거쳐 주사 전자 현미경을 이용한 파절면 분석을 시행하였다. 임플란트 파절면 분석 시 피로 줄무늬, 벽개 파절 등의 파절 지표를 통해 피로 파절로 인해 파절이 발생되었음을 확인할 수 있었다.

Sealer의 사용이 임프란트 나사의 안정성에 미치는 영향 (A STUDY ON THE STABILITY OF IMPLANT SCREW BY USE OF THE SEALER)

  • 이흥태;김낙형;정재헌
    • 대한치과보철학회지
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    • 제39권4호
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    • pp.366-375
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    • 2001
  • The objective of this study was to investigate the surface contact and screw joint stability between screw and implant interface by use of sealer. The implants evaluated in this study were Steri-Oss futures(Hexlock $3.8D{\times}10mm$: Steri-Oss, Yorba Linda, CA), and Steri-Oss staight abutment. Titanium alloy screws were used to secure abutments to implants. The other titanium alloy screws applicating sealer(Impla-Seal, Implant Support Systems, Inc. Irvine, CA) were used to secure abutments to implants. In one another sample, 6kg of force was applied during simulated intraoral movements after abutment screws were secured to the implants with sealer. All samples were cross sectioned with sandpaper and polished with $0.1{\mu}m\;Al_2O_3$. Then samples were recorded with an scanning electron microscope. The results were as follows : 1. In the case of titanium alloy screw, irregular contacts and relatively large gap were present at thread mating surface. Also abutment screw/implant interface demonstrate incomplete seating and only one surface contact of threads between implant and screw. 2. In the case of titanium alloy screw applecating sealer, sealer was present between implant and screw. Therefore implant and screw had relatively close and tight contact without the presence of large gap. 3. On the other hand, in the case of titanium alloy screw applicating sealer and dynamic loading of suprastructures, sealer was partially present between implant and screw. Conclusively, sealer fills voids, creating a barrier to moisture and bacteria. In addition, loading of suprastructures may change the situation and limit the indications for gap sealing.

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CONSTRAINING COSMOLOGICAL PARAMETERS WITH IMAGE SEPARATION STATISTICS OF GRAVITATIONALLY LENSED SDSS QUASARS: MEAN IMAGE SEPARATION AND LIKELIHOOD INCORPORATING LENS GALAXY BRIGHTNESS

  • Han, Du-Hwan;Park, Myeong-Gu
    • 천문학회지
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    • 제48권1호
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    • pp.83-92
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    • 2015
  • Recent large scale surveys such as Sloan Digital Sky Survey have produced homogeneous samples of multiple-image gravitationally lensed quasars with well-defined selection effects. Statistical analysis on these can yield independent constraints on cosmological parameters. Here we use the image separation statistics of lensed quasars from Sloan Digital Sky Survey Quasar Lens Search (SQLS) to derive constraints on cosmological parameters. Our analysis does not require knowledge of the magnification bias, which can only be estimated from the detailed knowledge on the quasar luminosity function at all redshifts, and includes the consideration for the bias against small image separation quasars due to selection against faint lens galaxy in the follow-up observations for confirmation. We first use the mean image separation of the lensed quasars as a function of redshift to find that cosmological models with extreme curvature are inconsistent with observed lensed quasars. We then apply the maximum likelihood test to the statistical sample of 16 lensed quasars that have both measured redshift and magnitude of lens galaxy. The likelihood incorporates the probability that the observed image separation is realized given the luminosity of the lens galaxy in the same manner as Im et al. (1997). We find that the 95% confidence range for the cosmological constant (i.e., the vacuum energy density) is $0.72{\leq}{\Omega}_{\Lambda}{\leq}1.0$ for a flat universe. We also find that the equation of state parameter can be consistent with -1 as long as the matter density ${\Omega}_m{\leq}0.4$ (95% confidence range). We conclude that the image separation statistics incorporating the brightness of lens galaxies can provide robust constraints on the cosmological parameters.

흰 쥐의 선상 절개 창상모델에서 저출력 레이저 자극이 조직 염증반응에 미치는 영향 (The Effects of Low Power Laser Treatment on Tissue Inflammatory Reactions in the Linear Incision Wound on Rat Skin)

  • 임인혁;이정원;김현숙
    • 한국전문물리치료학회지
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    • 제10권2호
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    • pp.61-70
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    • 2003
  • The purposes of this study was to evaluate the effect of low power GaAsAl laser on tissue contraction in a linear incision wound on rat skin. The linear incision wound was made on the midline of the backside in the experimental animals. Low power laser applications with different intensities such as 3, 6, or 10 mW were applied to the experimental animals twice a day for 10 days. On either the seventh or tenth postoperative day, the quantitative analysis of the inflammatory reaction surrounding the linear incision wounds on the rats were performed using enzymatical analysis of myeloperoxidase (MPO) activity. The number of neutrophil was $.07-1.0{\times}106/m{\ell}$ from a normal blood sample that was obtained from the normal experimental animals. Each concentration of neutrophil showed .04-.62 unit activity of MPO. Therefore, the 6 unit activity of MPO per neutrophil was $.57{\pm}.014{\times}10^{-6}$ unit. On the 7th and 10th post operative day, non treated tissues demonstrated increased MPO activity as compared to that of normal tissue. These data indicated that the inflammatory reaction of tissue was induced after wound induction and the MPO activity were increased in the inflammed tissues. While both 3 mW or 6 mW intensity of laser treatments did not affect the tissue MPO activity, 10 mW intensity of laser treatment significantly decreased the tissue MPO activity on the 7th and 10th post operative day. These data demonstrated that only 10 mW intensity of laser treatment successfully suppressed tissue inflammatory reaction after wound induction. In conclusion, these findings suggested that 10 mW of GaAIAs laser treatments effectively suppressed the inflammatory reaction of tissue that was induced during the wound healing process.

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저소득.일반가정 유아의 학습관련 기술과 초기학습능력: 어머니 교육참여의 조절효과를 중심으로 (Learning-related Skills and Academic Abilities of Young Children: The Moderating Effects of Their Mothers' Involvement)

  • 김영희;박지현
    • 한국지역사회생활과학회지
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    • 제22권1호
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    • pp.145-154
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    • 2011
  • This study investigated the effects of young children's learning-related skills and the maternal involvement on academic abilities. The sample consisted of 310 children from 7 child-care centers located in Seoul and Gyeonggi Province. All variables were measured by the teachers and the mothers of surveyed children. The instrument included the Korean Child Development Inventory(K-CDI) for 4 to 6-year olds and Preschool Learning Behavior Scale(McDermott et al 2000) and the questionnaire on mother's involvement about their children's education. The collected data was analyzed by t-test and hierarchical regression using the SPSS Program. The findings are as follows. First, regardless of the family income level, verbal comprehension and numerical abilities were positively associated with their learning-related skills of young children. Second, the interaction effect of learning-related skills and the mothers' involvement on verbal comprehension of young children in the low-income families was observed. However, no interaction effect was seen in terms of learning-related skills and the maternal involvement on verbal comprehension and numerical abilities of young children in the high-income families. These findings highlight the importance of learning-related skills and their mothers' involvement during the preschool period for the low-income family in improving the early academic achievement.

어육중의 riboflavin 함량의 측정 (Determination of Riboflavin Content in Fishes)

  • 송영옥;조덕문;변재형
    • 한국수산과학회지
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    • 제20권3호
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    • pp.219-223
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    • 1987
  • 초산연법 어육중의 riboflavin 함량측정에 적용가능한지를 검토하기 위하여 riboflavin 함량과 형광강도 상관성을 검량곡선으로 비교검토하였으며, 그 회귀식을 구하였다. 1. 초산연법은 개량 AOAC법에 비하여 정확도가 높고 실험방법이 간단 신속하므로 실험상의 오차를 줄일 수 있어 어육중의 riboflavin 함량측정에 적용할 수 있는 방법일 것으로 판단된다. 2. 백색어육류의 riboflavin 함량을 초산연안법으로 측정하였은 때 riboflavin 함량과 형광강도와의 상관식은 y=129.70x+0.71 이었다. 3. 9종의 백색육어류의 riboflavin 함량은 생식료 100g 중 $0.29\~0.48mg$ 4. 말쥐치육을 18일간 빙장한 결과, riboflavin의 함량변화는 미미하였다.

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Breast Cancer Knowledge, Perception and Breast Self-Examination Practices among Yemeni Women: an Application of the Health Belief Model

  • Al-Sakkaf, Khaled Abdulla;Basaleem, Huda Omer
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권3호
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    • pp.1463-1467
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    • 2016
  • Background: The incidence of breast cancer is rapidly increasing in Yemen with recent indications of constituting one-third of female cancers. The main problem in Yemen remains very late presentation of breast cancer, most of which should have been easily recognisable. Since stage of disease at diagnosis is the most important prognostic variable, early diagnosis is an important option to be considered for control of breast cancer in low resourced settings like Yemen. In the present study, we aimed at describing breast cancer knowledge, perceptions and breast self-examination (BSE) practices among a sample of Yemeni women. Materials and Methods: This cross-sectional study covered 400 women attending four reproductive health centres in Aden, Yemen through face-to-face interview using a structured questionnaire during April - July 2014. We collected data on sociodemographic characteristics, knowledge about breast cancer, and screening practices as well as respondents' perceptions based on the five sub scales of the Health Belief Model (HBM): perceived susceptibility; perceived severity; perceived barriers; perceived benefits; and self-efficacy. The response format was a five-point Likert scale. Statistical Package for Social Sciences (SPSS 20) was used for statistical analysis. Statistical significance was set at p<0.05. Logistic regression analysis was conducted with BSE as a dependent variable. Results: The mean age of women was 26.5 (S.D=5.6) years. The majority (89.0%) had never ever performed any screening. Two-thirds of respondents had poor knowledge. Perceived BSE benefits and self-efficacy and lower BSE barriers perception were significant independent predictors of BSE practice. Conclusions: Poor knowledge and inadequate BSE practices are prevailing in Yemen. The need for implementing culturally sensitive targeted education measures is mandatory in the effort to improve early detection and reduce the burden of breast cancer.

Exploration of Barriers to Breast-Self Examination among Urban Women in Shah Alam, Malaysia: A Cross Sectional Study

  • Al-Dubai, Sami Abdo Radman;Ganasegeran, Kurubaran;Alabsi, Aied M.;Manaf, Mohd Rizal Abdul;Ijaz, Sharea;Kassim, Saba
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권4호
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    • pp.1627-1632
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    • 2012
  • Background: Breast cancer is the most common cancer among women in Malaysia. Barriers for practicing breast self examination (BSE) await exploration. Objective: To assess the practice of BSE and its correlated factors and particularly barriers amongst urban women in Malaysia. Methods: This cross-sectional study was conducted with 222 Malaysian women using a self-administered questionnaire. Results: The mean (SD) age was 28.5 (${\pm}9.2$) years, 59.0% were university graduates. Of the total, 81.1% were aware of breast cancer and 55% practiced BSE. Amongst 45% of respondents who did not practice BSE, 79.8% did not know how to do it, 60.6% feared being diagnosed with breast cancer, 59.6% were worried about detecting breast cancer, 22% reported that they should not touch their bodies, 44% and 28% reported BSE is embarrassing or unpleasant, 29% time consuming, 22% thought they would never have breast cancer or it is ineffective and finally 20% perceived BSE as unimportant. Logistic regression modeling showed that respondents aged ${\geq}45$ years, being Malay, married and having a high education level were more likely to practice BSE (p<0.05). Conclusion: In this study sample, a significant proportion of respondents was aware of breast cancer but did not practice BSE. Knowledge, psychological, cultural, perception and environmental factors were identified as barriers. BSE practice was associated significantly with socio-demographic factors and socioeconomic status.

A Metal Enhanced Flow-Injection Chemiluminescence Method for the Rapid Determination of Norfloxacin in Pharmaceutical Formulations and Serum Sample

  • Kamruzzaman, Mohammad;Ferdous, Taslima;Alam, Al-Mahmnur;Lee, Sang-Hak;Kim, So-Yeun;Kim, Young-Ho;Kim, Sung-Hong
    • Bulletin of the Korean Chemical Society
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    • 제32권2호
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    • pp.639-644
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    • 2011
  • A simple and highly sensitive chemiluminescence method to determine norfloxacin (NFLX) has been proposed by measuring the chemiluminescence (CL) intensities using a flow injection (FI) system. The CL intensity of the luminol-$H_2O_2$ system is strongly enhanced by the addition of Cu (II) in alkaline condition. The CL intensity is substantially increased after the injection of NFLX into the luminol-$H_2O_2$-Cu (II) system. The enhancement effect is attributed to a catalytic effect of Cu (II) due to the interaction with NFLX which forms a complex with the catalyst. Under the optimal conditions, the sensitizing effect of the CL intensity is proportional to the concentration of NFLX in the range of $1.5{\times}10^{-9}-5.9{\times}10^{-7}molL^{-1}$ (r = 0.9994) with a detection limit ($3{\sigma}$) of $2.98{\times}10^{-10}molL^{-1}$. The proposed method had good reproducibility with the relative standard deviation (RSD, n = 5) of 1.6% for $1{\times}10^{-7}molL^{-1}$ of NFLX. The possible reaction mechanism of the CL reaction is also discussed. This method has been successfully applied for the determination of trace amount of NFLX in pharmaceutical preparations and serum samples.

에스트로젠 호르몬 대치요법이 혈압, 심박동변이, 갱년기증상에 미치는 효과 (The Effects of Estrogen Replacement Therapy on Blood Pressure, Heart Rate Variability, and Climacteric Symptoms in Postmenopausal Women)

  • 이혜경
    • 여성건강간호학회지
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    • 제8권2호
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    • pp.151-164
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    • 2002
  • PURPOSE: Estrogen replacement therapy is indicated for the relief of hot flushes and urogenital atrophy, the prevention of osteoporosis and the reduction in risk of cardiovascular disease. The present study assessed by blood pressure, heart rate variability, and climacteric symptoms in menopausal women before treatment and at 1 month during estrogen replacement therapy. METHODS: The study sample consisted of 16 healthy menopausal women (range 49 to 59 years, mean : 53.4 years) attending menopausal clinics for the complaint of climateric symptoms at S. hospital in Chunchoen. They were all non-smokers and no patient had symptoms or evidence of cardiovascular disease. They took estrogen replacement therapy (conjugated estrogen 0.625 mg with or without medroxy progesteron 2.5mg) for 1 month. Blood pressure, heart rate variability(heart period and vagal tone) through ECG, and climacteric symptom were measured in all subjects before treatment and at 1 month during treatment. Climacteric symptom questionnaire which was developed by Neugarten et al.(1963) was modified with 20 items of question(Cronbach's alpha = 88 -.89). The data was collected from Sept. 1. 2000 to July. 30. 2001. RESULTS: There was no significant difference in mean systolic and diastolic pressure between the baseline and at 1 month during treatment. The mean heart period and vagal tone were slightly increased, but difference of mean heart period and vagal tone were not statistically significant between the baseline and at 1 month during treatment. The score of climacteric symptoms decreased significantly from the baseline after treatment. CONCLUSIONS: Even though, this study did not show that estrogen replacement therapy led decrease of blood pressure and increase heart rate variability, climacteric symptoms reduced much in all subjects after taking drugs. These results suggest that there is need to repeat study with long term period.

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