• Title/Summary/Keyword: Functional levels

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H-induced Magnetism at Stepped Si (100) Surface

  • Lee, Jun-Ho;Cho, Jun-Hyung
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.211-211
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    • 2012
  • Using spin-polarized density-functional theory calculations, we find that the existence of either Peierls instability or antiferromagnetic spin ordering is sensitive to hydrogen passivation near the step. As hydrogens are covered on the terrace, the dangling bond electrons are localized at the step, leading to step-induced states. We investigate the competition between charge and spin orderings in dangling-bond (DB) wires of increasing lengths fabricated on an H-terminated vicinal Si(001) surface. We find antiferromagnetic (AF) ordering to be energetically much more favorable than charge ordering. The energy preference of AF ordering shrinks in an oscillatory way as the wire length increases. This oscillatory behavior can be interpreted in terms of quantum size effects as the DB electrons fill discrete quantum levels.

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Green Light-emitting diode using a germyl-substituted PPV derivative

  • Hwang, Do-Hoon;Lee, Jeong-Ik;Cho, Nam-Sung;Shim, Hong-Ku
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.582-584
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    • 2004
  • The light-emitting properties of poly(2-triethylgermyl-1,4-phenylenevinylene) (TEG-PPV) are compared with those of the silyl-substituted PPV homologue, poly(2-trimethylsilyl-1,4phenylenevinylene) (TMS-PPV). The precursor polymer is solution-processable. After carrying out thermal elimination on the precursor polymer film, the resulting fully conjugated polymer film was found to exhibit high thermal stability in air, and absorption that is shifted to the longer wavelength region owing to the extension of the n-conjugated system. TEG-PPV exhibits efficient green light emission; the maximum PL emission of a TEG-PPV thin film was found to be at 515 nm. The HOMO and LUMO energy levels were also determined using photo-emission spectroscopy. The performance of the TEG-PPV EL device was found to be comparable to that of the TMS-PPV device.

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Esthetic Realignment of Periodontally Compromised Anterior Teeth (치주질환으로 인한 전치부 정출(Extrusion)의 심미적 수복에 관한 증례)

  • Choi, Won-Seok
    • Journal of the Korean Academy of Esthetic Dentistry
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    • v.8 no.1
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    • pp.60-63
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    • 1999
  • Dental clinicians commonly encounter extrusion of the anterior teeth due to localized alveolar bone loss in adult patients with chronic periodontitis. This pathologic migration of the anterior not only may cause loss of functional anterior guidance and continuous periodontal destruction, but also can lead to esthetic disaster. In fact, most frequently reported chief complaint of the patients with extruded anterior teeth is the 'loss of esthetics', not the periodontal problem itself. The utilization of the expertise and skills in the various dental disciplines is thought to be the best treatment modality for the ultimate functional and esthetic attainment. Interdisciplinary therapy, involving periodontics, orthodontics, and restorative dentistry, was performed for the highest levels of patient and provider satisfaction in this case.

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Biomedicinal implications of high-density lipoprotein: its composition, structure, functions, and clinical applications

  • Cho, Kyung-Hyun
    • BMB Reports
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    • v.42 no.7
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    • pp.393-400
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    • 2009
  • High-density lipoprotein (HDL) is a proven biomarker for the monitoring of changes in antioxidant and anti-inflammation capability of body fluids. The beneficial virtues of HDL are highly dependent on its lipids and protein compositions, and their ratios. In normal state, the HDL particle is enriched with lipids and several HDL-associated enzymes, which are responsible for its antioxidant activity. Lower HDL-cholesterol levels (<40 mg/dL) have been recognized as an independent risk factor for coronary artery disease, as well as being a known component of metabolic syndrome. Functional and structural changes of HDL have been recognized as factors pivotal to the evaluation of HDL-quality. In this review, I have elected to focus on the functional and structural correlations of HDL and the roles of HDL-associated apolipoproteins and enzymes. Recent clinical applications of HDL have also been reviewed, particularly the therapeutic targeting of HDL metabolism and reconstituted HDL; these techniques represent promising emerging strategies for the treatment of cardiovascular disease, for drug or gene therapy.

Functional Mediastinal Pheochromocytoma

  • Lee, Jang Hoon;Lee, Seok Soo;Lee, Jung Cheul;Kim, Myeong Su;Choi, Joon Hyuk
    • Journal of Chest Surgery
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    • v.46 no.1
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    • pp.88-91
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    • 2013
  • A 36-year-old man visited Yeungnam University Hospital with a sudden onset of palpitation, headache, and was found to be hypertensive. Chest radiography showed a 6 cm sized mass lesion on the posterior mediastinum. A biochemical study showed elevated levels of catecholamines. An I-123 metaiodobenzylguanidine scan revealed a hot uptake lesion on the posterior mediastinum. The patient was prepared for surgery with ${\alpha}$ and ${\beta}$ blocking agents. Two months later, we removed the tumor successfully. A histological study proved that the resected tumor was mediastinal pheochromocytoma. Functional mediastinal pheochromocytomas are rare. Therefore, we reported the case with a literature review.

Physical Therapy Approaches for Respiratory Diseases (호흡계 질환의 물리치료적 접근방법)

  • Kim, Ki-Song
    • Journal of Korean Physical Therapy Science
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    • v.16 no.3
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    • pp.67-74
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    • 2009
  • Background: Various functional factors should be incorporated during assessment and intervention for patient rehabilitation. Stable respiratory function is one of required factors for functional restoration. To maximize respiratory physical therapy intervention outcome, it is required to understand clinical features of respiratory diseases and physical therapy approaches. Methods: Previous studies were systematically reviewed through computerized search. Methodological qualities of selected studies were evaluated and the levels of recommendations were determined. Results: Assessment for respiratory pattern and thoracic mobility is of importance to improve cardiopulmonary fitness during physical reconditioning. Application of optimal therapeutic protocol can increase thoracic mobility and respiratory function. Interdisciplinary communication is critical during rehabilitation for respiratory patients. Health care provider should have professional knowledge and experience for cardiopulmonary fitness and obligation to endeavor for patients' respiratory rehabilitation. It is necessary to standardize therapeutic intervention, and rehabilitative respiratory exercise should be applied to confirm the effects of intervention. Conclusion: Respiratory diseases that may reduce patients' quality of life and cardiopulmonary fitness should be resolved through physical therapy approaches. Through conducting research, effect of evidence-based and patients' function-oriented intervention can be determined.

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RNA Interference in C. elegans: History, Application, and Perspectives

  • Min, Kyoeng-Woo;Lee, Jun-Ho
    • Animal cells and systems
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    • v.11 no.2
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    • pp.99-104
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    • 2007
  • RNA interference (RNAi) is the phenomenon of gene silencing by double-stranded RNA (dsRNA) at transcriptional and post-transcriptional levels in a sequence-specific manner. Reverse genetic approaches using RNA interference (RNAi) have become a major tool for biological researches since its discovery in the nematode Caenorhabditis elegans. In this review, we overview how the RNAi phenomenon was discovered and how the underlying mechanism has been elucidated. We also describe and discuss how RNAi experiments can be performed and how RNAi can be used for genetic studies.

Development and Evaluation of a Patient Garment Based on Functional-Modesty-Aesthetic (FMA) Model

  • Koo, Helen S.;Min, Seoha
    • International Journal of Costume and Fashion
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    • v.14 no.2
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    • pp.67-79
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    • 2014
  • Recent research suggested that hospitals have not responded to consumer demand for the improved aesthetic and comfort of their patient garments. Thus a new patient garment has been developed considering human factors based on the Functional-Modesty-Aesthetics model. Based on the reviewed literature and the model, necessary design requirements were identified. Then the patient garment was evaluated in comparison to existing ones with regard to potential patients' satisfaction levels. As a result, the developed patient garment received better evaluations in the aspects of overall aesthetic satisfaction, color satisfaction, and willingness to wear than the existing patient garments.

A Study on the Science and Technology Level of Strategic Items in Korea (우리나라 10대 전략제품의 과학기술수준 조사연구)

  • 한성구;정근하;이상엽
    • Proceedings of the Technology Innovation Conference
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    • 2000.06a
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    • pp.153-173
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    • 2000
  • This study is focused on measuring levels of science and technology aspect of ten strategic items in korea to serve as a guidance for the government R&D policy-making, and provide appropriate information for promoting the national R&D programs. The survey of the precise technology level for study applies functional and technical parameters. Functional parameters are used for measuring technology level of the specification and performance of emerging items such as 256M DRAM, TFT-LCD ect. in the present and / or near future; technical parameters, the element / core technologies on emerging items. The study suggests that the result of the survey should be applied for strategic technology planning to narrow the technology gap and draw the criteria for resource allocation in national R&D programs.

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Characteristics of Pinitol as a Functional Food Biomaterial (건강기능성 식품소재로서 pinitol의 특성)

  • Son, Min-Sik;Seo, Myung-Seon;Lee, Sang-Han
    • Journal of Life Science
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    • v.19 no.1
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    • pp.147-151
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    • 2009
  • D-pinitol, another chemical structure of 3-O-methyl-D-chiro-inositol, is an important insulin-sensitizer. The purpose of this review is to examine the characteristics of pinitol and other analogs as functional food biomaterials which were well known to reduce blood glucose levels. Pinitol can be converted to chiro-inositol in normal humans, while diabetic patients can not use the molecule, resulting in exhibiting low level of chiro-inositol in their urine. Recently, it is reported that pinitol can trigger phospholipase C/D, thus the rate of glucose metabolism accelerates to use as fuel for human body. To not only reduce insulin resistance of diabetic patients, but also alleviate the symptoms of diabetes, obesity, and muscle contraction, pinitol and its dietary supplementation is needed.