• 제목/요약/키워드: University of British Columbia

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The effect of occlusogingival placement of clinical bracket points on the adaptation of a straight wire to the lingual arch form

  • Abdi, Amir Hossein;Motamedian, Saeed Reza;Balaghi, Ehsan;Nouri, Mahtab
    • The korean journal of orthodontics
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    • v.48 no.4
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    • pp.236-244
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    • 2018
  • Objective: The aim of this study is to compare the adaptation of a straight wire between brackets positioned at the mid-lingual surface and those placed gingivally by using a three-dimensional simulation software. Methods: This cross-sectional study was performed using OrthoAid, an in-house software. The subjects were 36 adolescents with normal Class I occlusion. For each dental cast, two bracket positioning approaches, namely the middle and gingival, were examined. In the middle group, the reference points were placed on the mid-lingual surface of each tooth, while in the gingival group, the reference points were positioned lingually on the anterior teeth. A 4th degree polynomial was adopted, and the in-plane and off-plane root mean squares (RMSs) of the distances between the reference points and the fitted polynomial curve were calculated using the software. Statistical analysis was performed using the paired-samples t-test (${\alpha}=0.05$). Results: The mean in-plane RMS of the polynomial curve to the bracket distance in the gingival group was significantly lower than that in the middle group (p < 0.001). The off-plane RMS was higher in the gingivally positioned brackets in the maxilla than in the middle group (p < 0.001). However, the off-plane RMS in mandible was not statistically significantly different between the two groups (p = 0.274). Conclusions: The results demonstrated that the gingival placement of lingual brackets on the anterior teeth could decrease the distance between a tooth and the straight wire.

Validation of the Korean Version of the Biological Rhythms Interview of Assessment in Neuropsychiatry

  • Cho, Chul-Hyun;Jung, Seo-Yeon;Kapczinski, Flavio;Rosa, Adriane R;Lee, Heon-Jeong
    • Psychiatry investigation
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    • v.15 no.12
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    • pp.1115-1120
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    • 2018
  • Objective The Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN) is a scale used to clinically evaluate disturbances in biological rhythm. In this study, we aimed to examine the reliability and validity of the Korean version of the BRIAN (K-BRIAN) in a Korean population. Methods A total of 181 participants, including 141 outpatients with bipolar disorder (BD; type I, 62; type II, 79) and 40 controls, were recruited. Construct validity was tested by comparing the mean K-BRIAN scores of the BD patients and control subjects. Concurrent validity was tested by evaluating the association between the K-BRIAN and the Morningness-Eveningness Questionnaire (MEQ). Results The mean K-BRIAN scores of the control subjects and patients with BD differed significantly (p<0.001). Particularly, the mean K-BRIAN score was considerably lower among control subjects (mean${\pm}$standard deviation=$35.00{\pm}8.88$) than among patients with BD type I ($41.19{\pm}12.10$) and type II ($50.18{\pm}13.73$). The Cronbach's alpha for the K-BRIAN was 0.914. The K-BRIAN was found to correlate with the MEQ (r=-0.45, p<0.001). Conclusion The findings affirm that the K-BRIAN has good construct validity and internal consistency. This suggests that the K-BRIAN can be used to assess biological rhythms in the Korean population, especially for patients with mood disorder.

Attachment systems for mandibular implant overdentures: a systematic review

  • Kim, Ha-Young;Lee, Jeong-Yol;Shin, Sang-Wan;Bryant, S. Ross
    • The Journal of Advanced Prosthodontics
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    • v.4 no.4
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    • pp.197-203
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    • 2012
  • PURPOSE. The aim of this systematic review was to address treatment outcome according to attachment systems for mandibular implant overdentures in terms of implant survival rate, prosthetic maintenance and complications, and patient satisfaction. MATERIALS AND METHODS. A systematic literature search was conducted using PubMed and hand searching of relevant journals considering inclusion and exclusion criteria. Clinical trial studies on mandibular implant overdentures until August, 2010 were selected if more than one type of overdenture attachment was reported. Twenty four studies from 1098 studies were finally included and the data on implant survival rate, prosthetic maintenance and complications, patient satisfaction were analyzed relative to attachment systems. RESULTS. Four studies presented implant survival rates (95.8 - 97.5% for bar, 96.2 - 100% for ball, 91.7% for magnet) according to attachment system. Ten other studies presented an implant survival rate ranging from 93.3% to 100% without respect to the attachment groups. Common prosthetic maintenance and complications were replacement of an assay for magnet attachments, and activation of a matrix or clip for ball or bar attachments. Prosthetic maintenance and complications most commonly occurred in the magnet groups. Conflicting findings were found on the rate of prosthetic maintenance and complications comparing ball and bar attachments. Most studies showed no significant differences in patient satisfaction depending upon attachment systems. CONCLUSION. The implant survival rate of mandibular overdentures seemed to be high regardless attachment systems. The prosthetic maintenance and complications may be influenced by attachment systems. However patient satisfaction may be independent of the attachment system.

Field Treatments of Small Diameter Logs Using Sap Displacement Method (I) - Feasibility of Treatment Using Transpiration Method and Butt-end Method - (수액치환법을 이용한 소경재의 산지처리(I) - 증산법과 원구법을 이용한 처리 가능성 -)

  • Chun, Su-Kyoung;Kim, Jae-Jin;Ra, Jong-Bum;Kim, Gyu-Hyeok
    • Journal of the Korean Wood Science and Technology
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    • v.30 no.4
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    • pp.58-65
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    • 2002
  • This research was carried out to develop field treatment techniques of thinned small diameter softwood logs and less utilized hardwood logs using sap displacement method. In this paper, we report the feasibility of using transpiration method and butt-end method for the treatment of three softwood species and three hardwood species with preservatives, fire-retardant chemicals, and dimensional stabilizer. Butt-end method was effective as a field treatment technique compared to transpiration method when considered the treatability, easiness of treatment, productivity of treated wood, and environmental aspects related to chemical treatment, regardless of the combination of wood species and chemicals.

Implementing and Evaluating a Nurse Led Hereditary Cancer Genetics Educational Program in a Korean Breast Cancer Surgery Clinic (한국형 유방 난소 종양유전상담 프로그램 적용 및 평가)

  • Choi, Kyung-Sook;Jun, Myung-Hee;Ahn, Sei-Hyun;Anderson, Gwen
    • Korean Journal of Adult Nursing
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    • v.20 no.6
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    • pp.815-828
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    • 2008
  • Purpose: This study was to develop and evaluate the clinical utility of the breast and ovarian cancer genetic counselling program specific for 20 Korean women(KBOCGP). Methods: The KBOCGP was developed using three types of approaches: an ethnography among Korean women who underwent BRCA1/2 test, designing and implementing one week clinical genetic educational course for clinical cancer nurses, educational observation visits to three American cancer genetic counselling programs. And then pre-experimental design was implicated to evaluate the change of the women's knowledge about the hereditary breast and ovarian cancer and the level of the satisfaction with genetic counselling. Results: The mean score of the knowledge has significantly increased from $7.45{\pm}3.86$ to $11.55{\pm}2.21$ (t = 5.63, p < .001). The level of the satisfaction with the counselling was very high ($27.47{\pm}1.35$). Because most of the subjects have young kids, they showed strong concerns about their kids' getting cancer. Conclusion: This new KBOCGP is the satisfactory program for the education and communication of the genetic information to the Korean women with HBOC. But it is needed more to strengthen the cultural sensitivity especially to Korean family relationships. Authors recommend that this program be provided by other nurses who are counselling women at high risk of breast cancer.

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Removing Sapstain of Radiata Pine by Bleaching (표백에 의한 라디에타소나무의 청변 제거)

  • Kim, Gyu-Hyeok;Kim, Hyung-Jun;Ra, Jong-Bum;Kim, Jae-Jin
    • Journal of the Korean Wood Science and Technology
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    • v.31 no.1
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    • pp.46-51
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    • 2003
  • The feasibility of using bleaching treatments for removing fungal stain was evaluated on heavily stained raiadta pine sapwood. Sodium chlorite and sodium hypochlorite appeared to destain fungal discoloration by providing proper treatment conditions (chemical concentration, treatment temperature, and treatment time), while hydrogen peroxide did not remove fungal stain under the bleaching regimes evaluated. The addition of sodium silicate and sodium hydroxide in the hydrogen peroxide solution as a buffer could remove fungal discoloration completely; however, the color of wood surface turned faint green after bleaching, thereby reducing the lightness of bleached samples. The results suggest that hydrogen peroxide bleaching could be a feasible method for removing fungal discoloration of stained radiata pine sapwood, although further research is needed to solve the problem of color change after bleaching. Also, further tests under field conditions are recommended.

Solvent Extraction of Preservative Components from CCA Treated Wood (CCA 처리재로부터 방부제 유효성분의 용제추출)

  • Kim, Gyu-Hyeok;Kong, Il-Gon;Ra, Jong-Bum;Cho, Jae-Sung;Kim, Jae-Jin
    • Journal of the Korean Wood Science and Technology
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    • v.31 no.4
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    • pp.50-56
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    • 2003
  • This research was performed to select an appropriate agent to extract preservative components from CCA-treated wood, and then to evaluate the effect of reagent concentration, extracting temperature, and extracting time on the removal of chrome, copper, and arsenic from treated wood. Hydrogen peroxide was selected as the best extracting agent when considered extraction yield as well as use and environmental safety. Its extraction yield was dependent on extracting variables (temperature, concentration, and time), and a highly significant interaction existed among variables. It should be possible to optimize extraction by manipulating these extracting variables. The results may suggest that the required temperature conditions for the reasonable removal of CCA components are at least above 40℃ because extracting time is too long at low temperature (20℃). Reagent concentrations for extracting at above 40℃ should be decided by considering the extracting time.

Polarization-sensitive Optical Coherence Tomography Imaging of Pleural Reaction Caused by Talc in an ex vivo Rabbit Model (생체 외 토끼 모델에서의 탈크에 의해 유발되는 흉막 반응의 편광 민감 광 결맞음 단층촬영 이미징)

  • Park, Jung-Eun;Xin, Zhou;Oak, Chulho;Kim, Sungwon;Lee, Haeyoung;Park, Eun-Kee;Jung, Minjung;Kwon, Daa Young;Tang, Shuo;Ahn, Yeh-Chan
    • Korean Journal of Optics and Photonics
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    • v.31 no.1
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    • pp.1-6
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    • 2020
  • The chest wall, an organ directly affected by environmental particles through respiration, consists of ribs, a pleural layer and intercostal muscles. To diagnose early and treat disease in this body part, it is important to visualize the details of the chest wall, but the structure of the pleural layer cannot be seen by chest computed tomography or ultrasound. On the other hand, optical coherence tomography (OCT), with a high spatial resolution, is suited to observe pleural-layer response to talc, one of the fine materials. However, intensity-based OCT is weak in providing information to distinguish the detailed structure of the chest wall, and cannot distinguish the reaction of the pleural layer from the change in the muscle by the talc. Polarization-sensitive OCT (PS-OCT) takes advantage of the fact that specific tissues like muscle, which have optical birefringence, change the backscattered light's polarization state. Moreover, the birefringence of muscle associated with the arrangement of myofilaments indicates the muscle's condition, by measuring retardation change. The PS-OCT image is interpreted from three major perspectives for talc-exposure chest-wall imaging: a thickened pleural layer, a separation between pleural layer and muscle, and a phase-retardation measurement around lesions. In this paper, a rabbit chest wall after talc pleurodesis is investigated by PS-OCT. The PS-OCT images visualize the pleural layer and muscle, respectively, and this system shows different birefringence of normal and damaged lesions. Also, an analyisis based on phase-retardation slope supports results from the PS-OCT image and histology.

On validation of fully coupled behavior of porous media using centrifuge test results

  • Tasiopoulou, Panagiota;Taiebat, Mahdi;Tafazzoli, Nima;Jeremic, Boris
    • Coupled systems mechanics
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    • v.4 no.1
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    • pp.37-65
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    • 2015
  • Modeling and simulation of mechanical response of infrastructure object, solids and structures, relies on the use of computational models to foretell the state of a physical system under conditions for which such computational model has not been validated. Verification and Validation (V&V) procedures are the primary means of assessing accuracy, building confidence and credibility in modeling and computational simulations of behavior of those infrastructure objects. Validation is the process of determining a degree to which a model is an accurate representation of the real world from the perspective of the intended uses of the model. It is mainly a physics issue and provides evidence that the correct model is solved (Oberkampf et al. 2002). Our primary interest is in modeling and simulating behavior of porous particulate media that is fully saturated with pore fluid, including cyclic mobility and liquefaction. Fully saturated soils undergoing dynamic shaking fall in this category. Verification modeling and simulation of fully saturated porous soils is addressed in more detail by (Tasiopoulou et al. 2014), and in this paper we address validation. A set of centrifuge experiments is used for this purpose. Discussion is provided assessing the effects of scaling laws on centrifuge experiments and their influence on the validation. Available validation test are reviewed in view of first and second order phenomena and their importance to validation. For example, dynamics behavior of the system, following the dynamic time, and dissipation of the pore fluid pressures, following diffusion time, are not happening in the same time scale and those discrepancies are discussed. Laboratory tests, performed on soil that is used in centrifuge experiments, were used to calibrate material models that are then used in a validation process. Number of physical and numerical examples are used for validation and to illustrate presented discussion. In particular, it is shown that for the most part, numerical prediction of behavior, using laboratory test data to calibrate soil material model, prior to centrifuge experiments, can be validated using scaled tests. There are, of course, discrepancies, sources of which are analyzed and discussed.

From Corridors to Intercity Networks : The Role of the Emerging Urban System in Building Regional Networks in Northeast Asia

  • Terry G. McGee;Xiaomin Pang;Shin, Dong-Ho
    • Journal of the Korean Regional Science Association
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    • v.15 no.2
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    • pp.21-38
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    • 1999
  • This paper is concerned with analyzing the role of Northeast Asia intercity networks in Northeast Asia in creating regional networks. For the purpose of this paper, we have followed Choe's (1996) definition of Northeast Asia which includes the Russian Fat East, the Northeast region of China, South Korea, North Korea and Japan. The central hypothesis of the paper is that the geopolitical conditions of Northeast Asia compared for example with Southeast Asia, favor bilateral rather than multilateral linkages between nation states. In these circumstances, it is our hypothesis that cities will play an important role in developing a "local image" of regio-nalism and intercity networks. In order to analyze this hypothesis, the paper is divided into three parts. Part A analyzes the emerging urban system of the Northeast Asia region using Choe's concept of the BESETO corridor and updating his data from the late 1980s to the mid 1990s just prior to the financial crisis. This analysis is further supported by the analysis of economic and transportation linkages within the urban system of the region with some discussion of emerging urban nodes. Part B looks at the specific case studies of the region including the Bohai Sea region, the Japan Sea and case studies of Sapporo, the Japan Sea and case studies of Sapporo, Pusan and Shandong province cities. Part C summarizes this preceding analysis and that the development of regionalism and servicing urban nodes is move likely to emerge from a myriad of linkages developed between the region's cities than from a supra-regional role of nation states. This finding has important implications for regional policy formation suggesting that there should be considerate national support for international linkages between cities.en cities.

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