POSTER SESSION : GROWTH - PHASE REGULATION OF THE ESCHERICHIA COLI THIOREDOXIN GENE

Chang Jin Lim,Tom Daws,James A . Fuchs 생화학분자생물학회(구 한국생화학분자생물학회) 1996 추계학술대회집 Vol.- No.-

Fractured styloid process masquerading as neck pain: Cone-beam computed tomography investigation and review of the literature

Khan, Hassan M.,Fraser, Andrew D.,Daws, Steven,Thoppay, Jaisri,Mupparapu, Mel Korean Academy of Oral and Maxillofacial Radiology 2018 Imaging Science in Dentistry Vol.48 No.1

Historically, Eagle syndrome is a term that has been used to describe radiating pain in the orofacial region, foreign body sensation, and/or dysphagia due to a unilateral or bilateral elongated styloid process impinging upon the tonsillar region. Because elongated styloid processes-with or without associated Eagle syndrome-can present with various symptoms and radiographic findings, it can be challenging for healthcare practitioners to formulate an accurate diagnosis. Abnormal styloid anatomy can lead to a multitude of symptoms, including chronic orofacial/neck pain, thus masquerading as more commonly diagnosed conditions. In this report, we describe a patient who presented to our department with styloid process elongation and fracture. A careful history, physical examination, and a cone-beam computed tomography (CBCT) investigation led to the diagnosis. The patient was then referred for appropriate care. This case report demonstrates the utilization of CBCT in differentiating a fracture site from a pseudo-joint that might mimic a fracture.

Fractured styloid process masquerading as neck pain: Cone-beam computed tomography investigation and review of the literature

Hassan M. Khan,Andrew D. Fraser,Steven Daws,Jaisri Thoppay,Mel Mupparapu 대한영상치의학회 2018 Imaging Science in Dentistry Vol.48 No.1

Historically, Eagle syndrome is a term that has been used to describe radiating pain in the orofacial region, foreign body sensation, and/or dysphagia due to a unilateral or bilateral elongated styloid process impinging upon the tonsillar region. Because elongated styloid processes-with or without associated Eagle syndrome-can present with various symptoms and radiographic findings, it can be challenging for healthcare practitioners to formulate an accurate diagnosis. Abnormal styloid anatomy can lead to a multitude of symptoms, including chronic orofacial/neck pain, thus masquerading as more commonly diagnosed conditions. In this report, we describe a patient who presented to our department with styloid process elongation and fracture. A careful history, physical examination, and a conebeam computed tomography (CBCT) investigation led to the diagnosis. The patient was then referred for appropriate care. This case report demonstrates the utilization of CBCT in differentiating a fracture site from a pseudo-joint that might mimic a fracture.

Van Der Waals Force Mediated, Rotationally Aligned Dry-Transfer-Stacking of Two-Dimensional Tungsten Diselenide

Daw Debottam,Sebait Riya,Biswas Chandan 한국물리학회 2020 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.77 No.10

Rotationally aligned, two-dimensional (2D), transition-metal dichalcogenides (TMDs) exhibit unique electronic, optical, and optoelectronic properties compared to random stacking. Rotationally aligned graphene stacking was demonstrated previously for numerous exotic phenomena, such as superconductivity, resonant tunneling, and moiré pattern. However, rotationally aligned dry-transfer techniques of TMDs, have yet to be demonstrated. Here, we show a simple method of selective cutting of a few-layer tungsten diselenide (WSe2) flake and rotationally aligning it by using dry-transfer stacking. The dry transfer techniques used for this study were adapted to maintain low sample contamination, a high-quality interface, a low number of defects. A combination of viscoelastic and thermoelastic materials was used for the TMD pickup and release to facilitate the rotationally aligned stacking. Aligned WSe2 stacks were characterized by Raman and photoluminescence spectroscopy to evaluate the integrity of the fabricated stack. This study highlights the possibility of using a rotationally aligned, artificial stacking method for exfoliated TMD materials for future electronic and optoelectronic applications.

Controlling the Properties of OPEFB/PLA Polymer Composite by Using Fe2O3 for Microwave Applications

Daw Mohammad Abdalhadi,Zulkifly Abbas,Ahmad Fahad Ahmad,Khamirul Amin Matori,Fahmiruddin Esa 한국섬유공학회 2018 Fibers and polymers Vol.19 No.7

Microwave-absorptive polymer composite materials provide protection against interference to communication systems caused by microwave-inducing devices. Microwave-absorptive polymer composites were prepared from polylactic acid (PLA) biocomposite blended with oil palm empty fruit bunch (OPEFB) fiber and commercial Iron oxide (Fe2O3) as filler using the melt-blending method. The composites characterization was carried out using the scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses. The coefficient of reflection S11 and coefficient of transmission S21 of the composites for various Fe2O3 filler percentages were determined using a rectangular waveguide in connection with microwave vector network analyser (HP/Agilent model PNA N5227). These coefficients were then used to calculate microwave-absorption properties (in decibels). XRD analysis showed that increasing amounts of reinforced material (Fe2O3) reduces the crystallinity of the composites. SEM data indicated that Fe2O3 filler ratio increased in the composites, and adhesion to the cellulose fiber grew gradually until the highest percentage of filler was added. The complex relative permittivity and relative permeability were obtained within the broad frequency range of 8-12 GHz at room temperature for various percentages of filler and were measured by the transmission/reflection method using a vector network analyser. Fe2O3 embedment in OPEFB/PLA was observed to have resulted in enhancing the dielectric and magnetic properties. The values of permittivity and permeability increased with increasing Fe2O3 filler content. Theoretical simulation studied the relation between ε' and ε" of the relative complex permittivity in terms of Cole-Cole dispersion law. The result indicated that the processes of Debye relaxation in Fe2O3/OPEFB/PLA, the unique dielectric characteristics of Fe2O3 cannot be accounted for by both the Debye dipolar relaxation and natural resonance. Results further showed that the material transmission, reflection, and absorption properties could be controlled by changing the percentage of Fe2O3 filler in the composites.

Springback prediction of the vee bending process for high-strength steel sheets

Daw-Kwei Leu,Zhi-Wei Zhuang 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.3

The precise prediction of springback is a key to assessing the accuracy of part geometry in sheet bending. A simplified approach is developed by considering the thickness ratio, normal anisotropy, and the strain-hardening exponent to estimate the springback of vee bending based on elementary bending theory. Accordingly, a series of experiments is performed to verify the numerical simulation. The calculation of the springback angle agrees well with the experiment, which reflects the reliability of the proposed model. The effects of process parameters such as punch radius, material strength, and sheet thickness on the springback angle are experimentally tested to determine the dominant parameters for reducing the springback angle in the sheet bending process for high-strength steel sheets. Moreover, the effects of the thickness ratio, normal anisotropy, and the strain-hardening exponent on the springback angle in the vee bending process for high-strength steel sheets are theoretically studied. Therefore, improving understanding on and control of the springback reduction of the vee bending process in practical applications is possible.

Positional deviation of bending point in asymmetric V-die bending process of HSS sheet: an experimental study

Daw-Kwei Leu 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.1

In this study, a series of experiments are performed to characterize the asymmetric V-die bending process for a High-strength steel(HSS) sheet. The main challenge in asymmetric V-die bending is positional deviation of the bending point during bending, given by amagnitude and a direction of deviation of the bending point. The effects of process parameters, such as radii of the punch head and thedie shoulder, on the positional deviation of the bending point were experimentally examined to identify those that govern the deviation ofthe bending point in an asymmetric bending process. This work improves our understanding of deviations of the bending point, and canbe used for developing process design guidelines for asymmetric bending of high-strength steel sheets to produce precise, asymmetricallybent parts.

Evaluation of friction coefficient using simplified deformation model of plastic hemispherical contact with a rigid flat

Daw-Kwei Leu 대한기계학회 2010 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.24 No.8

This work evaluates the friction coefficient using the model of plastic hemispherical contact against a rigid flat. The fractional profile of an ellipsoid is utilized to describe the deformed hemispherical shape, and simultaneously define the contact area ratio. Particularly, an adhesion factor is defined to assess the junction ability of asperity adhesion under compressive loading. Additionally, the complex process of contact is assumed as a series of contact states changing from fracture to shearing. The friction coefficient, which obeys the constant friction law, is then derived as a function of interference and strain hardening exponent via adhesion theory. Finally, a comparison of friction coefficient is made with the published experiment, showing that the calculated value is larger than the experimental value. Some practical conclusions are presented and a conceptual understanding of contact friction is provided.

Democracy and Development in Asia

( Daw Aung San Suu Kyi ) 서울대학교 통일평화연구원 2013 Asian Journal of Peacebuilding Vol.1 No.1

Responses of Eukaryotic Cells to Oxidative Stress

Dawes, Ian W. The Korean Society for Applied Biological Chemistr 2000 Journal of Applied Biological Chemistry (J. Appl. Vol.43 No.4

Oxidative stress is implicated in a number of diseases, in ageing of organisms, and in damage to plants that have been exposed to freezing and thawing or water stress. From the perspective of yeast as a model eukaryotic system, this article reviews the systems that are involved in the cellular responses to exposure to reactive oxygen species (ROS) generated during aerobic growth of the organism. The discussion includes the defense systems involved, the ability of cells to adapt to ROS treatment, cell-division cycle delay and the systems regulating gene expression that are activated by oxidative stress.