• 한국치위생학회지
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• 제11권5호
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• pp.615-627
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• 2011

Objectives : The study has three aims: 1) to assess the perceptions, attitudes, and behaviors of dental hygiene students and other college students towards oral and dental care, 2) to provide grounds for developing an oral and dental health educational program, and 3) to improve the oral and dental health status among the college student population. Methods : The subjects in this study were 520 students who included dental hygiene students from J health college and other majors from a four-year university located in Seoul. The survey was conducted from September, 2010, to June 3, 2011. The collected 507 questionnaires were analyzed. The collected data were analyzed by the statistical package SPSS WIN 12.0, and the level of significance was set at 0.05. Results : 1. As for a daily toothbrushing frequency, the largest number of the students brushed their teeth three times a day, and the dental hygiene students did that more often than the other majors(p<0.001). Concerning awareness of the toothbrushing method and the time for the change of the toothbrush, the rolling method was more prevailing among the dental hygiene students than the others(p<0.001). 2. In regard to education experience about the toothbrushing method and satisfaction with the existing toothbrushing method, 64.7% of respondents ever received education about the toothbrushing method(p<0.001). 3. As to scaling experience and gingival bleeding, the dental hygiene students had more scaling experiences(p<0.001), and the other majors who underwent gingival bleeding from time to time outnumbered the dental hygiene students who did(p<0.01). 4. In relation to subjective oral health status, the dental hygiene students found themselves to be in better oral health than the other majors(p<0.001), and the latter had more parts of the mouth in which they didn't feel well than the former(p<0.01). The dental hygiene students were more concerned about their oral health(p<0.001) and felt more uncomfortable in chewing(p<0.05). The other majors felt more uncomfortable in pronunciation(p<0.01). Conclusions : The results of this study indicated that dental hygiene students strongly recognized the importance of knowledge, motivation, and self-care behaviors, and attitudes towards oral health and dental care compared to other college students. It suggested that regular educational programs for the college student population should be implemented to increase their concern for oral and dental issues and to improve their oral and dental health status.

• Safety and Health at Work
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• 제11권2호
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• pp.178-186
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• 2020

Background: Cognitive impairment is a public health burden. Our objective was to investigate associations between work hours and cognitive function. Methods: Multi-Ethnic Study of Atherosclerosis (MESA) participants (n = 2,497; 50.7% men; age range 44-84 years) reported hours per week worked in all jobs in Exams 1 (2000-2002), 2 (2002-2004), 3 (2004-2005), and 5 (2010-2011). Cognitive function was assessed (Exam 5) using the Cognitive Abilities Screening Instrument (version 2), a measure of global cognitive functioning; the Digit Symbol Coding, a measure of processing speed; and the Digit Span test, a measure of attention and working memory. We used a prospective approach and linear regression to assess associations for every 10 hours of work. Results: Among all participants, associations of hours worked with cognitive function of any type were not statistically significant. In occupation-stratified analyses (interaction p = 0.051), longer work hours were associated with poorer global cognitive function among Sales/Office and blue-collar workers, after adjustment for age, sex, physical activity, body mass index, race/ethnicity, educational level, annual income, history of heart attack, diabetes, apolipoprotein E-epsilon 4 allele (ApoE4) status, birth-place, number of years in the United States, language spoken at MESA Exam 1, and work hours at Exam 5 (β = -0.55, 95% CI = -0.99, -0.09) and (β = -0.80, -1.51, -0.09), respectively. In occupation-stratified analyses (interaction p = 0.040), we also observed an inverse association with processing speed among blue-collar workers (adjusted β = -0.80, -1.52, -0.07). Sex, race/ethnicity, and ApoE4 did not significantly modify associations between work hours and cognitive function. Conclusion: Weak inverse associations were observed between work hours and cognitive function among Sales/Office and blue-collar workers.

• Safety and Health at Work
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• 제11권1호
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• pp.33-40
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• 2020

Background: Exploratory study to investigate whether co-exposure to physical wrist stressors and chemicals is associated with carpal tunnel syndrome (CTS) in French male farmers and agricultural workers. Methods: Cross-sectional study of 711 men aged 30-65 years and working as either farmers or agricultural workers in 2009-2010 within a cohort covered by the French Agricultural Workers' and Farmers' Mutual Benefit Fund. CTS and exposure to physical wrist stressors and chemicals were assessed using a self-administered questionnaire. Associations between CTS and personal/medical factors, exposure to physical wrist stressors, exposure to chemicals, and co-exposure to physical wrist stressors and chemicals were studied using multivariate logistic regression models. Results: Forty-four men {5.6% [95% confidence interval (CI) 4.0-7.7]} reported that they had suffered from unilateral/bilateral CTS during the last 12 months. CTS was associated with age, current smoking [odds ratio (OR) = 2.1 (1.0-4.5)], and exposure to physical wrist stressors [OR = 2.6 (1.1-5.9)]. An association was found between CTS and co-exposure to physical wrist stressors and chemicals [OR = 3.3 (0.8-14.3), p = 0.044] in comparison with the no-exposure group. Conclusions: This exploratory study shows an association of CTS with exposure to biomechanical wrist stressors in male farmers and agricultural workers and suggests an association of CTS with co-exposure to physical wrist stressors and chemicals. Owing to the limitations of the study, this result must be confirmed by a prospective study with objective assessments of the outcome and exposure before drawing conclusions on the possible synergistic effects of mechanical stressors and chemicals on the impairment of the median nerve.

• 한국미생물·생명공학회지
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• 제38권3호
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• pp.322-328
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• 2010

발효홍어(홍어회)에 존재하는 박테리아 집단의 다양성을 확인하기 위해, 박테리아의 16S rDNA 절편들을 증폭하고 클로닝하여 라이브러리를 구축하였다. 삽입 서열의 염기서열을 결정한 후, BLAST 분석에 의해 미생물 동정을 하였다. 동일한 삽입서열 빈도를 계산하였을 때, 발효홍어(홍어회)에는 uncultured bacterium clone 054E11.b가 57.1% 나타남으로써 우점균으로 존재하고 있다고 추정하였다. 또한 발효홍어(홍어회) 현탁액을 한천배지에 도말하여 형성된 집락을 콜로니 PCR을 수행하였을 때, Pseudomonas sp. KC-EPS13 등 12 종의 박테리아가 동정되었다. 배양 의존적 방법과 배양 비의존적 방법으로 홍어회를 분석하였을 때, Psychrobacter sp. J466만이 두 가지 방법에서 모두 검출되었고 나머지 박테리아들의 균총은 상이하였다.

• 한국미생물·생명공학회지
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• 제38권3호
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• pp.315-321
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• 2010

비듬균(Malassezia furfur) 는 두피 질환을 일으키는 중요한 요소로써 오늘날 이러한 균들을 치료하는 치료제는 거의 없다. 몇몇의 전의 연구에서 오일들의 다양한 생물학적 활성이 보고되어졌지만 그것들의 항비듬균 활성은 거의 연구되지 않았고, 특히 Malassezia furfur에 대한 저해 활성은 보고되어 있지 않다. 따라서, 이 연구에서는 Malassezia furfur에 대한 식물 오일들의 저해활성을 평가하고, 이러한 오일 중에서 가장 활성이 좋은 오일을 가스 크로마토그래피(Gas chromatography-mass spectrometry)에 의해 성분을 분석하였다. 1차적으로 108개 오일의 스크리닝 과정에서 17개 오일[Allium sativum L., Carum carvi L., Coriandrum sativum L., Myroxylon balsamum var. pereirae Royle, Nepeta cataria L., Origanum vulgare L., Mentha pulegium L., Satureja hortensis L., Thymus vulgaris L. Thymus vulgaris L., Cinnamomum zeylanicum Blume, Pimenta dioica(L.) Merr., Eugenia caryophyllata Thumb.(Clove bud), Eugenia caryophyllata Thumb.(Clove leaf), Cymbopogon nardus L., Cymbopogon martinii Stapf., Citrus aurantifolia Swing. and Pimenta racemosa(Mill.) J.W.Moore] 이 2 mg/mL 의 농도에서 대조구인 이크라코나졸(itraconazole)과 비슷한 활성을 나타내었다. 이러한 17개 오일 중에서 Citrus auranifolia 오일이 가장 활성이 좋았으며, 처리농도 (1.5 mg/mL, 1.0 mg/mL, 0.5 mg/mL와 0.1 mg/mL) 에 따라 활성이 감소하는 경향을 보였다. 또한 Citrus auranifoli 오일의 가스크로마토그래피(GC-MS) 성분분석 결과 limonene, ${\gamma}$-terpinene and terpinolene의 함유율이 높은 것으로 나타났다. 그러므로 Citrus auranifolia 오일은 곰팡이 유래 질병들을 치료하기 위한 활성성분을 함유하고 있는 것으로 보인다.

• Korean Journal of Acupuncture
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• 제27권3호
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• pp.1-23
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• 2010

Objectives and methods : The Standards for Reporting Interventions in Clinical Trials of Acupuncture (STRICTA) were published in five journals in 2001 and 2002. These guidelines, in the form of a checklist and explanations for use by authors and journal editors, were designed to improve reporting of acupuncture trials, particularly the interventions, thereby facilitating their interpretation and replication. Subsequent reviews of the application and impact of STRICTA have highlighted the value of STRICTA as well as scope for improvements and revision. To manage the revision process a collaboration between the STRICTA Group, the CONSORT Group, and the Chinese Cochrane Centre was developed in 2008. An expert panel with 47 participants was convened that provided electronic feedback on a revised draft of the checklist. At a subsequent face-to-face meeting in Freiburg, a group of 21 participants further revised the STRICTA checklist and planned dissemination. Results : The new STRICTA checklist, which is an official extension of CONSORT, includes six items and 17 sub-items. These set out reporting guidelines for the acupuncture rationale, the details of needling, the treatment regimen, other components of treatment, the practitioner background, and the control or comparator interventions. In addition, and as part of this revision process, the explanations for each item have been elaborated, and examples of good reporting for each item are provided. In addition, the word "controlled" in STRICTA is replaced by "clinical", to indicate that STRICTA is applicable to a broad range of clinical evaluation designs, including uncontrolled outcome studies and case reports. Conclusions : It is intended that the revised STRICTA, in conjunction with both the main CONSORT Statement and extension for nonpharmacologic treatment, will raise the quality of reporting of clinical trials of acupuncture.

• 천문학회보
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• 제36권1호
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• pp.37.2-37.2
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• 2011

Our previous study on tiny pores (R < 2") observed by HINODE/Solar Optical Telescope (SOT) revealed that the plasma in the pores at the photosphere is always moving down and the pores are surrounded by the strong downward motions (highly red-shifted) of neighboring granulations. From this study, we speculated that the flow motions above the pore should be related with the motions at the photosphere, since the pore is strong magnetic field region. Meanwhile, SNU and KASI installed Fast Imaging Solar Spectrograph (FISS) in the Cude room of the 1.6 m New Solar Telescope (NST) at Big Bear Solar Observatory. FISS is a unique system that can do imaging of H-alpha and Ca II 8542 band simultaneously, which is quite suitable for studying of dynamics of chromosphere. To get some clue on the relationship between the photospheric and low-chromospheric motions at the pore region, we took a coordinate observation with NST/FISS and Hinode/SOT for new emerging active region (AR11117) on October 26, 2010. In the observed region, we could find two tiny pores and two small magnetic islands (SMIs), which have similar magnetic flux with the pores but does not look dark. Magnetic flux density and Doppler velocities at the photosphere are estimated by applying the center-of-gravity (COG) method to the HINODE/spectropolarimeter (SP) data. The line-of-sight motions above the photosphere are determined by adopting the bisector method to the wing spectra of Ha and CaII 8542 lines. As results, we found the followings. (1) There are upflow motion on the pores and downflow motion on the SMIs. (2) Towards the CaII 8542 line center, upflow motion decrease and turn to downward motion in pores, while the speed of down flow motion increases in the SMIs. (3) There is oscillating motion above pores and the SMIs, and this motion keep its pattern along the height. (4) As height increase, there is a general tendency of the speed shift to downward on pores and the SMIs. This is more clearly seen on the other regions of stronger magnetic field. In this talk, we will present preliminary understanding of the coupling of pore dynamics between the photosphere and the low-chromosphere.

• Journal of Genetic Medicine
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• 제7권1호
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• pp.45-52
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• 2010

목 적: 윌리암스증후군 아동의 인지와 관련된 두 가지 특성을 검증하고자 하였다; 윌리암스증후군 아동은 언어성 지능이 동작성 지능 보다 유의하게 높다; 윌리암스증후군 아동은 시공간기능의 선택적 저하를 보인다. 대상 및 방법: 평균연령 $90.86{\pm}20.73$개월의 5명의 윌리암스 증후군 아동의 인지적 특성을 연령 및 성별이 유사한 12명의 프라더윌리증후군 혹은 다운증후군 아동의 인지적 특성과 비교, 분석하였다. 결 과: 윌리암스증후군 아동에서 언어성 지능 항목의 합은 $15.71{\pm}9.27$, 동작성 지능 항목의 합은 $14.29{\pm}7.50$으로, 언어성 지능과 동작성 지능 간의 유의한 차이를 보이지 않았다. 윌리암스증후군, 프라더윌리증후군, 다운증후군 아동들간의 언어성 지능의 유의한 차이는 관찰되지 않았다. 윌리암스증후군 아동에서 시공간지각과 관여된 세부항목의 선택적 저하는 관찰되지 않았으나, 물체조합 항목에서 프라더윌리증후군 아동에 비하여 유의한 기능의 저하를 보였다. 결 론: 윌리암스증후군 아동이 전체 지능에 비하여 상대적으로 높은 언어성 지능을 보인다는 일반적인 개념은 본 연구에서는 관찰되지 않았다. 동시에 윌리암스증후군 아동은 프라더윌리증후군이나 다운증후군 아동과의 비교 시에도 우수한 언어기능을 보이지 않았다. 그러나 윌리암스증후군 아동은 프라더윌리증후군 아동과 비교 시 현저히 낮은 시공간기능을 보였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.59-59
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• 2010

Graphene is a 2-D sheet of $sp^2$-bonded carbon arranged in a honeycomb lattice. This material has attracted major interest, and there are many ongoing efforts in developing graphene devices because of its high charge mobility and crystal quality. Therefore clear understanding of the substrate effect and mechanism of synthesis of graphene is important for potential applications and device fabrication of graphene. In a published paper in J. Phys. Chem. C (2008), the effect of substrate on the atomic/electronic structures of graphene is negligible for graphene made by mechanical cleavage. However, nobody shows the interaction between Ni substrate and graphene. Therefore, we have studied this interaction. In order to studying these effect between graphene and Ni substrate, We have observed graphene synthesized on Ni substrate and graphene transferred on $SiO_2$/Si substrate through Raman spectroscopy. Because Raman spectroscopy has historically been used to probe structural and electronic characteristics of graphite materials, providing useful information on the defects (D-band), in-plane vibration of sp2 carbon atoms (G-band), as well as the stacking orders (2D-band), we selected this as analysis tool. In our study, we could not observe the doping effect between graphene and Ni substrate or between graphene and $SiO_2$/Si substrate because the shift of G band in Raman spectrum was not occurred by charge transfer. We could noticed that the bonding force between graphene and Ni substrate is more strong than Van de Waals force which is the interaction between graphene and $SiO_2$/Si. Furthermore, the synthesized graphene on Ni substrate was in compressive strain. This phenomenon was observed by 2D band blue-shift in Raman spectrum. And, we consider that the graphene is incommensurate growth with Ni polycrystalline substrate.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.456-456
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• 2010

CMOS 소자가 서브마이크론($0.1\;{\mu}m$) 이하로 스케일다운 되면서 단채널 효과(short channel effect), 게이트 산화막(gate oxide)의 누설전류(leakage current)의 증가와 높은 직렬저항(series resistance) 등의 문제가 발생한다. CMOS 소자의 구동전류(drive current)를 높이고, 단채널 효과를 줄이기 위한 가장 효율적인 방법은 소스 및 드레인의 얕은 접합(shallow junction) 형성과 직렬 저항을 줄이는 것이다. 플라즈마 도핑 방법은 플라즈마 밀도 컨트롤, 주입 바이어스 전압 조절 등을 통해 저 에너지 이온주입법보다 기판 손상 및 표면 결함의 생성을 억제하면서 고농도로 얕은 접합을 형성할 수 있다. 그리고 얕은 접합을 형성하기 위해 주입된 불순물의 활성화와 확산을 위해 후속 열처리 공정은 높은 온도에서 짧은 시간 열처리하여 불순물 물질의 활성화를 높여주면서 열처리로 인한 접합 깊이를 얕게 해야 한다. 그러나 접합의 깊이가 줄어듦에 따라서 소스 및 드레인의 표면 저항(sheet resistance)과 접촉저항(contact resistance)이 급격하게 증가하는 문제점이 있다. 이러한 표면저항과 접촉저항을 줄이기 위한 방안으로 실리사이드 박막(silicide thin film)을 형성하는 방법이 사용되고 있다. 본 논문에서는 (100) p-type 웨이퍼 He(90 %) 가스로 희석된 $PH_3$(10 %) 가스를 사용하여 플라즈마 도핑을 실시하였다. 10 mTorr의 압력에서 200 W RF 파워를 인가하여 플라즈마를 생성하였고 도핑은 바이어스 전압 -1 kV에서 60 초 동안 실시하였다. 얕은 접합을 형성하기 위한 불순물의 활성화는 ArF(193 nm) excimer laser를 통해 $460\;mJ/cm^2$의 에니지로 열처리를 실시하였다. 그리고 낮은 접촉비저항과 표면저항을 얻기 위해 metal sputter를 통해 TiN/Ti를 $800/400\;{\AA}$ 증착하고 metal RTP를 사용하여 실리사이드 형성 온도를 $650{\sim}800^{\circ}C$까지 60 초 동안 열처리를 실시하여 $TiSi_2$ 박막을 형성하였다. 그리고 $TiSi_2$의 두께를 측정하기 위해 TEM(Transmission Electron Microscopy)을 측정하였다. 화학적 결합상태를 분석하기 위해 XPS(X-ray photoelectronic)와 XRD(X-ray diffraction)를 측정하였다. 접촉비저항, 접촉저항과 표면저항을 분석하기 위해 TLM(Transfer Length Method) 패턴을 제작하여 I-V 특성을 측정하였다. TEM 측정결과 $TiSi_2$의 두께는 약 $580{\AA}$ 정도이고 morphology는 안정적이고 실리사이드 집괴 현상은 발견되지 않았다. XPS와 XRD 분석결과 실리사이드 형성 온도가 $700^{\circ}C$에서 C54 형태의 $TiSi_2$ 박막이 형성되었고 가장 낮은 접촉비저항과 접촉저항 값을 가진다.