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Objective Alzheimer’s disease (AD) is the most common type of dementia and the prevalence rapidly increased as the elderly population increased worldwide. In the contemporary model of AD, it is regarded as a disease continuum involving preclinical stage to severe dementia. For accurate diagnosis and disease monitoring, objective index reflecting structural change of brain is needed to correctly assess a patient’s severity of neurodegeneration independent from the patient’s clinical symptoms. The main aim of this paper is to develop a random forest (RF) algorithm-based prediction model of AD using structural magnetic resonance imaging (MRI).Methods We evaluated diagnostic accuracy and performance of our RF based prediction model using newly developed brain segmentation method compared with the Freesurfer’s which is a commonly used segmentation software.Results Our RF model showed high diagnostic accuracy for differentiating healthy controls from AD and mild cognitive impairment (MCI) using structural MRI, patient characteristics, and cognitive function (HC vs. AD 93.5%, AUC 0.99; HC vs. MCI 80.8%, AUC 0.88). Moreover, segmentation processing time of our algorithm (

Objective Previous studies investigating association of alcohol intake and fracture risk in elderly yielded conflicting results. We first examined the association between alcohol intake and total fracture risk in elderly subjects and further analyzed whether the association varied by fracture locations.Methods This is a nationwide population-based cohort study which included all people aged 66 (n=1,431,539) receiving the National Screening Program during 2009–2014. Time-to-event were defined as duration from study recruitment, the day they received health screening, to the occurrence of fracture.Results Total fracture was significantly lower in mild drinkers [adjusted hazard ratio (aHR)=0.952; 95% confidence interval (95% CI) =0.931–0.973] and higher in heavy drinkers (aHR=1.246; 95% CI=1.201–1.294) than non-drinkers. Risk pattern of alcohol consumption and fracture differed according to affected bones. Similar J-shaped trends were observed for vertebra fractures, but risk of limb fracture showed a linear relationship with alcohol intake. For hip fracture, risk decrement was more pronounced in mild and moderate drinkers, and significant increment was noted only in very severe drinkers [≥60 g/day; (aHR)=1.446; 1.162–1.801].Conclusion Light to moderate drinking generally lowered risk of fractures, but association between alcohol and fracture risk varied depending on the affected bone lesions.

Objective We aimed to explore the impact of moderate intensity exercise on the cortical thickness and subcortical volumes of preclinical Alzheimer’s disease (AD) patients.Methods Sixty-three preclinical AD patients with magnetic resonance imaging (MRI) and 18-florbetaben positron emission tomography (PET) data were enrolled in the study. Information on demographic characteristics, cognitive battery scores, self-reported exercise habits were attained. Structural magnetic resonance images were analyzed and processed using Freesurfer v6.0.Results Compared to Exercise group, Non-Exercise group demonstrated reduced cortical thickness in left parstriangularis, rostral middle frontal, entorhinal, superior frontal, lingual, superior parietal, lateral occipital, inferior parietal gyrus, temporal pole, precuneus, insula, fusiform gyrus, right precuneus, superiorparietal, lateral orbitofrontal, rostral middle frontal, medial orbitofrontal, superior frontal, lingual, middle temporal gyrus, insula, supramarginal, parahippocampal, paracentral gyrus. Volumes of right thalamus, caudate, putamen, pallidum, hippocampus, amygdala were also reduced in Non-Exercise group.Conclusion Moderate intensity exercise affects cortical and subcortical structures in preclinical AD patients. Thus, physical exercise has a potential to be an effective intervention to prevent future cognitive decline in those at high risk of AD.

High-precision printing machines are essential for the fabrication of more sophisticated printed electronics. In particular, roll-to-roll printing with flexible substrates and nonideal rolls, which exhibit cylindricity, misalignment, and run-outs, produces nonlinear effects that are hard to manage with conventional control systems. For instance, printing rolls with cylindricity and run-outs cause large perturbations in the printing forces. In this paper, we propose a hybrid printing force control system that provides uniform printing conditions in the regions where printing occurs. The unique parallel arrangement of two force components provides excellent regulation of the printing force; this system also consumes less power. Our experimental results verify that the force control performance of the hybrid force control system is better than that of a conventional system. We also report the results of in situ printing quality tests with a pressure-sensitive film that confirm the effectiveness of the proposed system.

Recently, various electronic devices, such as foldable displays, disposable sensors, and flexible batteries have been widely demanded. Accordingly, we tried to create extremely flexible conductive features that can tolerate severe mechanical stress using photonic sintering process. Additionally, based on significant differences in adhesion between light-exposed and non-exposed regions with respect to the underlying substrate, it was confmned that patterning of conductive electrodes could be easily accomplished on large area. The potential of IPL treated electronic conductive features were clearly demonstrated by fabricating various emerging devices such as a light-emitting diode circuit and a flexible transparent heater with unimpaired functionality under various deformations. Our results facilitate their widespread application in future electronics, such as wearable e-skins, smart textiles and foldable display.

A simple route to fabricate defect-free Ag-nanoparticle-carbon-nanotube composite-based high-resolution mesh flexible transparent conducting electrodes (FTCEs) is explored. In the selective photonic sintering-based patterning process, a highly soft rubber or thin plastic substrate is utilized to achieve close and uniform contact between the composite layer and photomask, with which uniform light irradiation can be obtained with diminished light diffraction. This well-controlled process results in developing a fine and uniform mesh pattern (≈12 μm). The mesh patternability is confirmed to be dependent on heat distribution in the selectively light-irradiated film and the pattern design for FTCE could be adopted for more precise patterns with desired performance. Moreover, using a very thin substrate could allow the mesh to be positioned closer to the strain-free neutral mechanical plane. Due to strong interfacial adhesion between the mesh pattern and substrate, the mesh FTCE could tolerate severe mechanical deformation without performance degradation. It is demonstrated that a transparent heater with fine mesh patterns on thin substrate can maintain stability after 100 repeated washing test cycles in which a variety of stress situations occurring in combination. The presented highly durable FTCE and simple fabrication processes may be widely adoptable for various flexible, large-area, and wearable optoelectronic devices.

Transparent conducting electrodes (TCEs) were developed through the roll-offset printing of Ag grid mesh patterns for the application of all-solution processed organic solar cells (OSCs). Due to the remarkable printability of roll-offset printing, the printed TCEs did not show the step coverage problem of subsequent thin layers, which was a chronic problem in other printing techniques. The control of ink cohesion was verified as a critical factor for the high printing quality, which was optimized by adding a polyurethane diol of 2 wt.%. The tensile strength of optimized Ag ink was 322 mN, which led to the clear patterning of Ag nanoparticles. The printed TCEs with different mesh densities of the Ag grid were designed to have a similar property of indium tin oxide (ITO). The measured sheet resistance was 13 Ω/□, and optical transmittance was 86%, including the glass substrate, which was found to be independent of wavelength in the visible spectrum, in contrast with the optical transmittance of ITO. To evaluate the TCE performance as bottom electrodes, all-solution processed OSCs were fabricated on top of the TCEs. The power conversion efficiency (PCE) of the OSCs increased with the increments of the mesh density due to the distinctive increase of the short circuit current density (J sc ), notwithstanding the similar transmittance and sheet resistance of the TCEs. In comparison with ITO, a higher PCE of OSCs was obtained because the printed TCEs with a high mesh density were able to facilitate effective current collection, leading to a significant increase of J sc .

High-linearity wideband transmitter with a high linearity Mixer and RF-PGA is proposed for 802.1af/ah long-range Wi-Fi standards. The transmitter is direct conversion architecture while supporting 1/2/4/6/8/16 MHz signal bandwidth for 802.11af/ah. Implemented in a 40-nm CMOS process with the chip size of 1.0 mm × 1.9 mm, the full transmitter shows a conversion gain range of 31.5 dB with 0.5 dB step and achieves EVM −36.8 dB (802.11 ah) and −37 dB (802.11af) in sub-GHz frequency bands. The measured OIP3 of the transmitter is from 20 dBm to 25 dBm, while consuming 36 mA with the supply voltage of 1.1/2V.

Flexible electronics have been to the fore because it is believed that flexibility can add incredible value such as light weight and mobility into the existing electronic devices and create new markets of large-area and low-cost electronics such as wearable eletronics in near future. Offset printing processes are regarded as major candidates for manufacturing the flexible electronics because they can provide the patterning resolution of micron-size effectively in large-area. In view of mechanics, the most important viewpoint in offset printing is how to achieve the synchronized movement of two contact surfaces in order to prevent slip between two contact surfaces and distortion of the blanket surface during ink transfer so that the high-resolution and good-overlay patterns can be printed. In this paper, a novel low-cost measurement method of the synchronization error using the motor control output signals is proposed and the compensation method is presented to minimize the synchronization error.

This paper presents an analytic model of cartwheel flexure. 6-DOF (degrees of freedom) stiffness equations for cartwheel flexure are derived and verified by comparing the model's predictions with FEM (finite element method) simulations and experiments. The model prediction accuracy relative to FEM simulations is found to be satisfactory, with errors of less than 10%. The deviation of the model's prediction from the experiments’ results is slightly higher because of body deformations and manufacturing errors. The effects of manufacturing errors on the model accuracy are analyzed, with the results indicating that the first mode is greatly affected by the manufacturing errors, while the thickness variation of the cartwheel flexure hinge has the largest effect on the model prediction accuracy. The cartwheel flexure hinge is evaluated in terms of the motion range, stiffness and stiffness ratio and compared with the conventional right circular hinge to confirm the appropriateness of the cartwheel flexure hinge as a large displacement flexure joint. Finally, an example of cartwheel flexure design is presented to show that the analytic stiffness model can provide a set of optimized design parameters in less time than FEM simulations.

Simple, low-cost and scalable patterning methods for Cu nanowire (NW)-based flexible transparent conducting electrodes (FTCEs) are essential for the widespread use of Cu NW FTCEs in numerous flexible optoelectronic devices, wearable devices, and electronic skins. In this paper, continuous patterning for Cu NW FTCEs via a combination of selective intense pulsed light (IPL) and roll-to-roll (R2R) wiping process was explored. The development of continuous R2R patterning could be achieved because there was significant difference in adhesion properties between NWs and substrates depending on whether Cu NW coated area was irradiated by IPL or not. Using a custom-built, R2R-based wiping apparatus, it was confirmed that nonirradiated NWs could be clearly removed out without any damage on irradiated NWs strongly adhered to the substrate, resulting in continuous production of low-cost Cu NW FTCE patterns. In addition, the variations in microscale pattern size by varying IPL process parameters/the mask aperture sizes were investigated, and possible factors affecting on developed pattern size were meticulously examined. Finally, the successful implementation of the patterned Cu NW FTCEs into a phosphorescent organic light-emitting diode (PhOLED) and a flexible transparent conductive heater (TCH) were demonstrated, verifying the applicability of the patterned FTCEs. It is believed that our study is the key step toward realizing the practical use of NW FTCEs in various flexible electronic devices.

In printed electronics technology, the overlay accuracy of printed patterns is a very important issue when applying printing technology to the production of electric devices. In order to achieve accurate positioning of the printed patterns, this study proposes a novel precision reverse offset printing system. Furthermore, the study evaluates the effects of synchronization and printing force on position errors of the printed patterns, and presents methods of controlling synchronization and printing force so as to eliminate positional errors caused by the above-mentioned reasons. Finally, the printing position repeatability of 0.40 μm and 0.32 μm (x and y direction, respectively) at a sigma level is obtained over the dimension of 100 mm under repeated printing tests with identical printing conditions.

This article presents the design and performance evaluation of a compact high precision XY -scanner providing nanometer-level resolution and a millimeter-level travel range. The proposed XY -scanner is composed of a voice coil motor (VCM) and double compound linear spring flexure guide mechanism. The challenge was to determine design variables properly while simultaneously satisfying the requirements of high resolution, long working range, high response speed, and compact size, because the relationships between the design variables and the system parameters are complex. Therefore, we developed a design that would provide the optimal tradeoff in terms of design variables. The objective was to maximize the first resonant frequencies of the XY -scanner to increase response speed while limiting the size of the scanner to 100 mm × 100 mm × 50 mm. The XY -scanner was fabricated with optimally-designed values, and its performance was evaluated. From the experimental results, the first resonant frequencies of XY -scanner were 26.68 Hz for the X -axis and 22.79 Hz for the Y -axis. The measured results of the 10 nm resolution and 2 mm working range confirmed that the designed scanner could be successfully used in precision fields requiring nanometer-level resolution and millimeter-level travel range.

We demonstrate an alignment method for a laboratory-scale soft X-ray microscope, which utilizes a liquid-jet laser-produced plasma source in combination with a tandem ellipsoidal condenser mirror and a diffractive micro zone plate. Because the intensity of the laser-produced plasma source is relatively low, we developed the tandem ellipsoidal condenser mirror to increase the photon density in the objective plane and to obtain a high-resolution image within a short exposure time. But, aligning the tandem ellipsoidal condenser mirror is a difficult task because it has 5 degrees of freedom (DOF) alignment tolerances and there is a connection among these tolerances. We performed its tolerance analysis and developed a new fully automated alignment algorithm via computer control. As a result, a 12.5-µm-pitch gold mesh image was measured using 700× magnification and a 5 min exposure and the resultant edge detection resolution was about 70 nm.

In this paper, the development of compact transmission soft x-ray microscopy (XM) with sub-50 nm spatial resolution for biomedical applications is described. The compact transmission soft x-ray microscope operates at lambda = 2.88 nm (430 eV) and is based on a tabletop regenerative x-ray source in combination with a tandem ellipsoidal condenser mirror for sample illumination, an objective micro zone plate and a thinned back-illuminated charge coupled device to record an x-ray image. The new, compact x-ray microscope system requires the fabrication of proper x-ray optical devices in order to obtain high-quality images. For an application-oriented microscope, the alignment procedure is fully automated via computer control through a graphic user interface. In imaging studies using our compact XM system, a gold mesh image was obtained with 45 nm resolution at x580 magnification and 1 min exposure. Images of a biological sample (Coscinodiscus oculoides) were recorded.

This article presents the design and control of an ultraprecision XYϑZ stage with nanometer accuracy. The stage has a plane mechanism and symmetric hexagonal structure which consists of a monolithic flexure hinge mechanism with three piezoelectric actuators and six flexures preserving the plane motion. The symmetric design reduces the effect of temperature gradient on the structure. Because the relationship between design variables and system parameters are quite complicated and there are some trade-offs among them, it is very difficult to set design variables manually and optimal design procedure is used. The objective of design is maximizing the 1st resonant frequency to improve the dynamic characteristics. The reason is that the stage must move with heavy load of about 20 kg. The higher resonant frequency also makes the stage stiffer and stronger against the dynamic force and moment. This paper describes the procedures of selecting parameters for the optimal design and a mathematical formulation for the optimization problem. The stage was designed to attain ±10 um in the X- and Y-direction and ±90arcsec in the yaw direction at the same time and have the 1st resonant frequencies of 455.5 Hz in X- and Y-direction and 275.3 Hz for yaw direction without load. The stage was fabricated according to the optimal design results and experimental results indicate that the design procedure is effective. A conventional PI control results are presented for ultraprecision motion.

Next-generation patterning processes have been extensively studied recently, with a view to replacing the photo-lithographic process and to reducing production costs. For micron scale patterning, the printing process is one of major candidates. In particular, contact printing is more promising in view of the possibilities for mass production. In this process, the motion of the two printing contact surfaces should be synchronized perfectly to prevent slip and unwanted distortion in the surfaces and to make precise ink transfer between the surfaces. In this article, a force-based direct measurement method of the synchronization error is proposed, and the effect of synchronization error on the printing process is analyzed.Copyright © 2013 by ASME

In roll-offset printing (patterning) technology with a PDMS blanket as a transfer medium, one of the major reliability issues is the occurrence of swelling, which involves absorption of the ink solvent in the printing blanket with repeated printing. This study developed a method to resolve blanket swelling in gravure offset roll printing and performed experiments for performance verification. The physical phenomena of mass and heat transfer were applied to fabricate a device based on convection drying. The proposed device managed to effectively control blanket swelling through drying by blowing air and additional temperature control. The experiments verified that printing quality (in particular the variation of the width of printed patterns) was maintained over 500 continuous printing.

In this presentation, the development of compact transmission soft x-ray microscopy (XM) as a imaging tool for sub-50nm spatial resolution hydrated cell imaging is described. The compact transmission soft x-ray microscope operates at λ = 2.88 nm (430eV) and is based on a tabletop regenerative x-ray source in combination with tandem ellipsoidal condenser mirror (TECM) for sample illumination, objective micro zone plate (OZP) and thinned back-illuminated charge coupled device (CCD) to record an x-ray image. The spectral resolution of illumination soft x-ray has been shown to be E/□E=1000. The new, compact x-ray microscope system requires the fabrication of proper x-ray optical devices in order to obatain high-quality images. For an application-oriented microscope, the alignment procedure is fully-automated via computer control through a graphic user interface. On imaging studies using our compact XM system, the gold mesh image was obtained with 45 nm resolution at ×580 magnification and 1 minute exposure. The images of the biological sample were recorded.

Interest in the production of printed electronics using a roll-to-roll system has gradually increased due to its low mass-production costs and compatibility with flexible substrate. To improve the accuracy of roll-to-roll manufacturing systems, the movement of the web needs to be measured precisely in advance. In this paper, a novel measurement method is developed to measure the displacement and velocity of the web precisely and directly. The proposed algorithm is based on the traditional single field encoder principle, and the scale grating has been replaced with a printed grating on the web. Because a printed grating cannot be as accurate as a scale grating in a traditional encoder, there will inevitably be variations in pitch and line-width, and the motion of the web should be measured even though there are variations in pitch and line-width in the printed grating patterns. For this reason, the developed algorithm includes a precise method of estimating the variations in pitch. In addtion, a method of correcting the Lissajous curve is presented for precision phase interpolation to improve measurement accuracy by correcting Lissajous circle to unit circle. The performance of the developed method is evaluated by simulation and experiment. In the experiment, the displacement error was less than 2.5 μm and the velocity error of 1σ was about 0.25%, while the grating scale moved 30 mm.

Actinomycosis is a chronic suppurative disease and caused by Actinomycosis species, principally Actinomyces israelii, which are part of the normal inhabitant on the mucous membrane of the oropharynx, gastrointestinal tract, and urogenital tract. It usually affects cervicofacial, thoracic and abdominal tissue. Cervicofacial type has the highest percentage of occurrence with 50%. Actinomycosis frequently occurs following dental extraction, jaw surgery, chronic infection or poor oral hygiene. It may also be considered as an opportunistic infection in immunocompromised patients such as malignancy, human immunodeficiency virus infection, diabetes mellitus, steroid usage or alcoholism. But, actinomycosis rarely occurs in adults with normal immunity and rare in the esophagus. We report an unusual case of esophageal actinomycosis which was developed in a patient with normal immunity and improved by therapy with intravenous penicillin G followed oral amoxicillin, and we also reviewed the associated literature.

Correspondence to Hyoung Jun Kim, M.D. Division of Cardiology, Department of Internal Medicine, Dongkang Hospital, 239 Taehwa-ro, Jung-gu, Ulsan 681-711, Korea Tel: +82-52-241-1114, Fax: +82-52-241-1180, E-mail: khj035@hanmail.net Copyrightc 2013 The Korean Association of Internal Medicine This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited. 베흐체트병에서 폐동맥 협착에 의한 중증 폐동맥 고혈압의 풍선 성형술

This paper details the development of a novel flexure jointed precision parallel nano-positioning system in combination with piezo-electric stepping motor for the application of precise optics alignment. The characteristics of the developed system are evaluated in this paper by the simulation and experiments. Based on the precision piezo-electric stepping motor and flexure joints, a high precision motion is obtained. Results of this paper include that of a translation resolution of 15 nm and a rotational resolution of 0.14 arc sec being achieved. In addition, the piezo-electric stepping motors provide a power-off hold characteristic to the system. Meanwhile, the parallel structure provides the high dynamic bandwidth of the lowest resonant frequency of 396.1 Hz. The symmetric structure is advantageous for thermal variation. To increase the motion range of the system, all of flexure joints are designed specially and the coupled workspace of ±2 mm × ±2 mm × ±2 mm × ±2° × ±2° × ±2° is achieved. The overall size of the designed system is Φ350 mm × 120 mm.

Behcet's disease is a rare multisystemic disorder whose main pathological defectis vasculitis, and superior vena cava (SVC) syndrome without thrombosis is a very rare manifestation of the disease. These authors encountered a case of SVC syndrome without thrombosis caused by Behcet's disease. A 33-year-old man visited the hospital for aggravated dyspnea without any related medical and familial history. He had a threeday history of abrupt swelling of the face, neck, and right arm. He suffered from recurrent oral ulcer, and there were acneiform nodules on his face as well as redness and swelling at the site of the intravenous injection. On the multi-detected computed tomography (CT) chest angiograms (chest angio MDCT), the SVC narrowed without thrombosis. Venogram was carried out, and percutaneous transluminal balloon angioplasty of the SVC stenotic site was performed. The following day, the swelling was found to have subsided. The details of the case are reported herein.

To establish of standard technique of nanolength measurement in a two-dimensional plane, a new (AFM) system has been designed. In this system, measurement uncertainty is dominantly affected by the Abbe error of the XYZ scanning stage. No linear stage is perfectly straight; in other words, every scanning stage is subject to tilting, pitch, and yaw motion. In this article, an AFM system with minimum offset of XYZ sensing is designed. And, the XYZ scanning stage is designed to minimize the rotation angle because Abbe errors occur through the multiply of offset and rotation angle. For XY stage, optimal design is performed to minimize the rotation angle by maximizing the stiffness ratio of motion direction to the parasitic motion direction of each stage. For the Z stage, the optimal design of maximizing the first-resonant frequency is performed. When the resonant frequency increases, the scan speed is improved, thereby reducing errors caused by sensor drift. This article describes the procedures of selecting p...