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We investigate the transport behavior of two-terminal graphene ballistic devices with bias voltages up to a few volts suitable for electronics applications. Four graphene devices based ballistic designs, specially fabricated from mechanically exfoliated graphene encapsulated by hexagonal boron nitride, exhibit strong nonlinear I-V characteristic curves at room temperature. A maximum asymmetry ratio of 1.58 is achieved at a current of 60 µA at room temperature through the ballistic behavior is limited by the thermal effect at higher bias. An analytical model using a specular reflection mechanism of particles is demonstrated to simulate the specular reflection of carriers from graphene edges in the ballistic regime. The overall trend of the asymmetry ratio depending on the geometry fits reasonably with the analytical model.

Fas‐associated factor 1 (FAF1) has gained a reputation as a member of the FAS death‐inducing signalling complex. However, the role of FAF1 in the immunity response is not fully understood. Here, we report that, in the human retinal pigment epithelial (RPE) cell line ARPE‐19 cells, FAF1 expression level was downregulated by Toxoplasma gondii infection, and PI3K/AKT inhibitors reversed T. gondii‐induced FAF1 downregulation. In silico analysis for the FAF1 promoter sequence showed the presence of a FOXO response element (FRE), which is a conserved binding site for FOXO1 transcription factor. In accordance with the finding, FOXO1 overexpression potentiated, whereas FOXO1 depletion inhibited intracellular FAF1 expression level. We also found that FAF1 downregulation by T. gondii is correlated with enhanced IRF3 transcription activity. Inhibition of PI3K/AKT pathway with specific inhibitors had no effect on the level of T. gondii‐induced IRF3 phosphorylation but blocked IRF3 nuclear import and ISGs transcription. These results suggest that T. gondii can downregulate host FAF1 in PI3K/AKT/FOXO1‐dependent manner, and the event is essential for IRF3 nuclear translocation to active the transcription of ISGs and thereby T. gondii proliferation.

Among various available materials used in transparent and flexible devices, MXenes are attracting attention as a brand-new candidate in this category. Ti3C2Tx MXene as a 2D material has exceptional properties, making it a potential material having numerous applications in different areas. Because of its high conductivity, it can be used in transparent conducting electrodes (TCEs). In this study, the MXenes etched by highly concentrated acid at 50 °C,were spin-coated on polyethylene terephthalate (PET) film and annealed at moderate temperatures up to 170 °C. The adhesion of MXene to PET was found to be remarkably improved by annealing. These TCEs exhibited a sheet resistance of ∼424 Ω/sq. and transmittance of ∼87%. The aging stability of MXene-coated PET films against oxidation under ambient conditions was studied up to 28 days and resistance change was found ∼30% during this period. The flexibility test showed low bending resistance change (∼1.5%) at 1000th cycle and cumulative resistance change of ∼20% at a bending radius of ∼3.9 mm after 1000 cycles. These transparent, flexible, and conducting electrodes were used to fabricate polymer dispersed liquid crystal (PDLC)-based flexible smart windows. The smart windows fabricated by curing PDLC mixture sandwiched between the MXene electrodes were also found flexible in ON/OFF states. The MXene-based flexible smart windows resulted in good opacity in the OFF state and high transparency in the ON state, exhibiting low threshold voltage

Purpose To compare the clinical and magnetic resonance imaging (MRI) outcomes of meniscal repair using absorbable versus nonabsorbable sutures in patients undergoing concomitant anterior cruciate ligament reconstruction. Methods Data of 142 patients who underwent meniscal repair with concomitant anterior cruciate ligament reconstruction using either absorbable or nonabsorbable sutures for longitudinal meniscal tear were retrospectively reviewed. Inside-out suture technique was used for all meniscal repairs. Weight bearing and flexion (>90°) were allowed after 6 weeks postoperatively. Clinical evaluations were assessed by the International Knee Documentation Committee subjective score, Lysholm score, and Tegner activity score preoperatively and at 2-year follow-up. MRI outcomes at 1-year follow-up were compared to identify the successful healing (complete or partial healing) rate and incidence of additional meniscal tears. Subgroup analysis was performed to evaluate the results of medial or lateral meniscus. Results Eighty patients underwent meniscal repair using absorbable sutures (mean age, 26.3 ± 11.9 years) and 62 patients with nonabsorbable sutures (mean age, 27.2 ± 10.0 years). There were no differences in zone and length of meniscal tears and stability tests between the groups. At a 2-year follow-up, all clinical scores had improved in both groups but did not differ significantly between the groups. Successful healing rate based on 1-year postoperative MRI was not significantly different between the absorbable and nonabsorbable sutures (93.7% vs 96.8%, P = .469). However, the absorbable sutures showed a lower additional tear incidence than the nonabsorbable sutures (2.5% vs 9.6%, P = .031). Subgroup analysis showed that the successful healing rate was not significantly different between the suture materials in both the medial and lateral menisci. Conclusions The use of absorbable sutures leads to comparable healing rates to and lower incidence of additional tears than nonabsorbable sutures in patients undergoing meniscal repair with anterior cruciate ligament reconstruction. Level of Evidence Level III, retrospective comparative therapeutic trial.

The effect of Ti3C2Tx MXene etched at different temperatures (25 °C, 50 °C, and 80 °C) on the capacitance of supercapacitors without the use of conducting carbon-black or a binder was studied. The MXene etched using concentrated HCl acid (12 M)/LiF was used as an active electrode and Ni-foil as a current collector. It was observed that the elevated etching temperature facilitates the etching of the MAX phase and the exfoliation of MXene layers. However, this led to the formation of additional functional groups at the MXene surface as the temperature was increased to 80 °C. The specific capacitance of Ti3C2Tx-based supercapacitors increased from 581 F g−1 for MXene etched at 25 °C to 657 F g−1 for those etched at 50 °C at the scan rate of 2 mV s−1. However, the specific capacitance reduced to 421 F g−1 as the etching temperature was increased to 80 °C at the same scan rate. The supercapacitors based on MXenes etched at the intermediate temperature (50 °C) exhibited higher specific capacitance in a wide range of scan rate, symmetry in charge/discharge curves, high cyclic stability at a scan rate of 1000 mV s−1 for up to 3000 cycles. The electrochemical impedance spectroscopy studies indicated low series resistance, reduced charge-transfer resistance, and decreased Warburg impedance for the supercapacitor based on the MXene etched at the intermediate temperature.

The long mean free path close to a micrometer in encapsulated graphene enabled us to rectify currents ballistically at room temperature. In this study, we introduce a ballistic rectifier that resembles a diode bridge and is based on graphene encapsulated using hexagonal boron nitride. Our device’s asymmetric geometry combined with the exploitation of the ratcheting effect means that it can operate successfully and provides excellent performance. The device’s estimated responsivities at 38,000 V/W for holes and 23,000 V/W for electrons at room temperature, are among the highest values for a ballistic device reported to date. Due to the device’s zero threshold voltage, it is able to rectify Johnson noise signals converting thermal excitation to electrical energy at room temperature. The bandwidth of the device at the ballistic regime is estimated at ~ 1.1 GHz for holes and 2 GHz for electrons. The device developed in this study is an important step along an innovative pathway that will lead to harvesting electrical energy directly from thermal energy.

Acupuncture point (AP) selections can vary depending on clinicians’ acupuncture style, and therefore, acupuncture style is an important factor in determining the efficacy of acupuncture treatment. However, few studies have examined the differences in AP selections according to the acupuncture styles and theoretical backgrounds causing the differences. We compared the AP prescriptions used for 14 diseases in three classical medical textbooks, Dongeuibogam (DEBG), Saamdoinchimgooyogyeol (SADI), and Chimgoogyeongheombang (CGGHB), which represent unique acupuncture styles and have affected clinicians during this time. AP prescriptions showed more diversity between textbooks than between types of diseases. Among the three textbooks, AP prescriptions of SADI were most different compared to those of DEBG and CGGHB. Importantly, we found each style can be more clearly explained by AP attributes than by the APs per se. Specifically, SADI, DEBG, and CGGHB preferred five transport points located on the limbs, APs of the extra meridians, and source points, respectively. This suggests the possibility that the theoretical diversity of acupuncture styles results in the heterogeneity of AP selections.

The effect of Ti

Among p–n junction devices with multilayered heterostructures with WSe2 and MoSe2, a device with the MoSe2–WSe2–MoSe2 (NPN) structure showed a remarkably high photoresponse, which was 1000 times hi...

In this study, series of experiments and finite element method analyses were conducted, and the results were used to demonstrate the effect of the autofrettage pressure on the cycling life and the failure mode, and to determine an optimal condition of autofrettage process for self-contained breathing apparatus. Total 20 vessels went through different autofrettage pressures, i.e., 1.0, 1.1, …, 2.9 times the test pressure. Then, each vessel was subjected to the ambient hydraulic cycling test of the same condition until fluid leaks. Cycling life of a vessel was estimated based on the stress-strain diagram and stress-cycle curve that were obtained by the tensile test and the fatigue test, respectively, of the liner sample. By using ABAQUS code, the compressive residual stress and the maximum strain distribution at each autofrettage pressure were computed. As a result, the failure modes were in good agreements with the computations. And it is concluded that the proportionality factor of 1.7 or above should be applied in the autofrettage process for significant extension of the cycling life, and, with the factor of 2.5, the maximum cycling life and the desired failure mod are achieved simultaneously.

Recently, we can find news about toxic and combustible gas accident. So, we have to develop gas detector that can measure gas at dangerous area for preventing gas accidents. In this paper, we calculate a approximation function from sensor's output using the linear regressiong. And we develop software algorithm using Neville's algorithm for measuring gas concentration. Finally, we compare our algorithm with combustible gas detectors that are already developed, by using standard gas samples manufactured Korea Gas Safety. As a result of this experiment, we confirm that performance of our algorithm is more improved than performance of already developed combustible gas detectors. In the future, we'll research how to improve reliability from using count, temperature and humidity. And we'll design hardware applied explosion proof for safety.

Purpose To investigate (1) the correlation between lateral posterior tibial slope (PTS) and clinical outcomes of lateral meniscus allograft transplantation (MAT) and (2) the difference of lateral PTS between the extrusion and nonextrusion groups or between the failure and nonfailure groups in lateral MAT. Methods Between January 2001 and February 2016, we retrospectively evaluated 61 patients (mean age, 29.1 ± 12.2 years) who underwent postoperative magnetic resonance imaging (MRI) and were followed for a minimum of 2 years after primary lateral MAT. The lateral PTS and graft extrusion in the coronal and sagittal planes were assessed by using MRI performed at 1 year postoperatively. Clinical scores and graft failure were evaluated at the last follow-up visit. The correlation between lateral PTS and clinical outcomes (clinical scores, graft extrusion) was analyzed. Lateral PTS was compared between the extrusion and nonextrusion groups and between the failure and nonfailure groups. Results Mean lateral PTS on MRI was 6.6° ± 3.1° (range, 0.8° to 15.7°). A significant correlation was not identified between lateral PTS and clinical outcomes (clinical scores, graft extrusion in the coronal and sagittal planes). A significant difference in lateral PTS was not identified between the extrusion and nonextrusion groups in the coronal (6.2° ± 2.5° vs 7.0° ± 3.4°, P = .400) and sagittal (anterior horn, 6.5° ± 2.3° vs 6.7° ± 3.7°, P = .988; posterior horn, 6.8° ± 3.5° vs 6.5° ± 2.7°, P = .771) planes. Moreover, a significant difference was not identified between the failure and nonfailure groups (7.5° ± 3.3° vs 6.4° ± 3.0°, P = .388). Conclusions A significant correlation between lateral PTS and clinical or radiologic outcomes of lateral MAT was not identified. Level of Evidence Level IV, therapeutic case series with subgroup analysis.

Heart rate and blood pressure monitoring during physical activity and exercise allow early diagnosis of cardiovascular disease (CVD) and obesity. Plethysmography(PPG) has become popular worldwide for personal health monitoring systems. However, the accuracy of this technology in monitoring heart rate and blood pressure during activity is poorer than at rest. It limits their application. In this study, the performance of the wearable sensor and arm cuff blood pressure meter in measuring heart rate and blood pressure on the left arm is compared. Five healthy volunteers conducted the same exercise protocols, i.e., at rest, jump rope, treadmill walking, running (long run) and sprinting (short-run). The wearable sensor shows a mean absolute percentage error in 6.08% and Pearson coefficient in 0.61. Besides, the lowest range of 95% limit of agreement for diastolic blood pressure during treadmill run was found at 30.50.

Recently, visible light communication(VLC) is being actively researched as green wireless communication services are drawing attention. Currently, VLC mostly uses LED for transmission and PD(Photo Diode) for receiving. However, this kind of system has limited applications. Therefore, we design and propose in this paper, a LED-to-LED two way VLC system that doesn`t use PD(Photo Diode). This system has the following features and contributions. First, this system uses just LED at both transmitter and receiver with analog switch, Second, this system support both one-way communication and two way communication together. One way communication can support multi-hop communication. The performance evaluation of the proposed system is conducted at a place with standard light. We test the success or failure of one way communication by changing distance and baud rate while test the success and failure of two way communication by changing distance. We expect that the proposed LED-to-LED system in this paper can be applied for various application fields.

As the interest in hydrogen energy is being increased, it is a widely issue to develop a lot of hydrogen technologies in the field of production, storage, transportation, application and others. In the aftermath, there is a hydrogen town in Ul San, which is expected to expand application fields of hydrogen energy, as a demonstration project. The hydrogen town in Ul San can consist of high and low pressure part by the gas pressure. The high pressure part is managed by 'the high pressure gas safety control act'. And, low pressure part is managed by 'the guideline for the safety management of demonstration project of hydrogen town'. In this paper, to improve efficiency of safety management, the direction of safety management is reviewed by an analysis of low pressure hydrogen facility and safety management items. And then, some improvement directions are suggested. In the end, it is expected that the results of this study could help to activate construction of hydrogen town and improve efficiency of safety management as well.

This research aims to increase the reliability and reproducibility of the ambient cycling test by properly making corrections to the test procedure. The vessel (106 L) is initially filled with 70 L of water and horizontally placed on a balance. The pressure range inside the vessel varies from 2.5 to 25.9 MPa at the frequency of 6 cycles per minute. After reviewing the results, there was a temperature difference of approximately 10 °C between the air pocket and the water, and the upper part of the liner faced a repeated temperature change of 40 °C. It is possible for the aluminum liner of the composite vessel to be damaged by such a sharp change in temperature. Additionally, as a result, no pass having anything to do with the purpose of the test would occur. Therefore, it is suggested that the air pocket be completely removed.KeyWords : Ambient Hydraulic Cycling Test(상온수압반복시험), Type3 Composite Vessel( 3 ),타입복합재용기 Internal Temperature Variations(내부온도변화) # Corresponding Author : sklyu@gnu.ac.kr Tel: +82-55-772-1632, Fax: +82-55-772-1578

To assess the diagnostic value of gadoxetic acid-enhanced magnetic resonance (MR) imaging in follow-up of patients with hepatocellular carcinomas (HCCs) who were treated with radiofrequency (RF) ablation and to compare it with that of four-phase multi-detector row computed tomography (CT).From July 2007 to May 2008, 36 patients (43 HCCs) were enrolled who were treated with RF ablation (tumor size, 20-47 mm; mean, 24.5 mm) and underwent gadoxetic acid-enhanced MR imaging and four-phase (precontrast, arterial, portal venous, and equilibrium) multidetector CT for follow-up. Two radiologists independently reviewed these images, and conspicuity of tumor margins and detection of residual or recurrent tumor were assessed on a five-point scale with receiver operating characteristic (ROC) curve analysis. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were evaluated.The mean conspicuity value of tumor margins was significantly higher on MR imaging than on multidetector CT (P.001). The degree of differentiation between residual/recurrent tumor and hyperemia was significantly greater on MR imaging (P.001). The mean area under the ROC curve was significantly higher with MR imaging (P = .015), as were sensitivity, specificity, PPV, NPV, and accuracy of detection rate (mean, 100%, 96.2%, 82.4%, 100%, and 96.7%, respectively, vs 41.7%, 56.8%, 13.5%, 85.7%, and 54.7% for multidetector CT). The interobserver agreement rate for MR imaging was higher (0.919) than for multidetector CT (0.672; P.05).Diagnostic accuracy, conspicuity of tumor margins, and detection rate of residual or recurrent tumor were found to be better with gadoxetic acid-enhanced MR imaging than with four-phase multidetector CT.

In this paper, we proposed a design of the field-supported portable ammonia detector. Ammonia gases are toxic gases so they stimulate nose and throat and cause many diseases. So, we designed the detector for detecting the ammonia gases more safely. The structure of this detector is a detachable structure. Its detection part and display part can be separated. It has algorithms of an accuracy improvement using least square method and Neville interpolation. Also, it can use Bluetooth communication. Bluetooth communication is used when the display part and detection part is separated. So, it can check, adjust, and transmit the measured data when it is separated. Furthermore, the measured data of concentration of ammonia gases can be transmitted to the smart devices using Bluetooth communication and can be manage the data in the smart devices.

In this paper, we developed and tested comparison performance of our developed Integrated Cathodic Protection Monitor (ICPM) with other instruments. ICPM is more accurate than other products due to using high impedances(100MO) to fit high soil specific resistances. And we achieved measuring of corrosion protection voltages at the fields and comparing of those data with other instruments. We demonstrated our ICPM more excellent than other products through experiments.

Recently, we can find news about toxic and combustible gas accident. So, we have to develop gas detector that can measure gas safely at dangerous area and be possible to monitor gas detection at remote area. In this paper, we analyze and estimate gas sensor modules and combustible gas detectors that is already developed, by using standard gas sample manufactured Korea Gas Safety. We apply result analyzed data from experience for developing next generation combustible gas detector.

EEFL can be driven by square wave driving method. A square wave is applied directly to both ends of EEFL by cascaded multi-stage full-bridge inverter. The various current shapes of lamp are achieved by various inductors between lamp and inverter. In this paper, it is newly investigated that the area of current directly influences the luminance. Furthermore, the 3-level square wave is considered to drive EEFL with self-discharge characteristics. The highest luminance efficiency is achieved by properly controlling the rate of self-discharge usage.

Amyloidosis is a disorder characterized by extracellular deposition of amyloid in various tissues and organs. Gastrointestinal manifestations including gastroparesis, constipation, malabsorption, intestinal pseudo-obstruction, and bleeding are common. GI bleeding is a rare initial symptom which can be fatal in some cases. Absence of systemic symptoms and nonspecific endoscopic findings in amyloidosis may make diagnosis difficult. Therefore, amyloidosis-induced GI bleeding should be considered in patients with an obscure hemorrhage. Recently, we experienced a 65-year-old woman who presented with massive hematochezia as a manifestations of amyloidosis. Colonoscopy and SMA angiography showed massive bleeding in the small and large intestine. Colonoscopic biopsy established amyloidosis. We report this case with a review of the relevant literatures.

The aim of this study was to identify the bacteria isolated from acute endodontic lesions by cell culture and 16S rDNA sequencing. The necrotic pulpal tissue was collected from 17 infected root canals, which were diagnosed as being either an acute pulpitis or acute periapical abscess. Samples were collected aseptically from the infected pulpal tissue of the infected root canals using a barbed broach and a paper point. The cut barbed broaches and paper points were transferred to an eppendorf tube containing 500 ul of 1 XPBS. The sample solution was briefly mixed and plated onto a BHI-agar plate containing sheep blood. The agar plates were incubated in a anaerobic chamber for 7 days. The bacteria growing on the agar plate were identified by 16S rRNA coding gene (rDNA) cloning and sequencing at the species level. Among the 71 colonies grown on the agar plates, 56 strains survived and were identified. In dental caries involving the root canals, Streptococcus spp. were mainly isolated. Actinomyces, Clostridia, Bacteroides and Fusobacteria were isolated in the periapical lesion without dental caries. Interestingly, two new Actinomyces spp. (ChDC B639 and ChDC B631) were isolated in this study. These results showed that there was diversity among the species in endodontic lesions, This suggests that an endodontic infection is a mixed infection with a polymicrobial etiology. These results may offer the bacterial strains for pathogenesis studies related to an endodontic infection.

For good endodontic obturation, a canal system that has been cleaned and shaped in all its dimensions is necessary. However, once this has been accomplished, the complete seal of the root canal system is an essential component in assuring longterm clinical success as it is this seal that maintains the barrier between the oral environment and the periradicular tissues. The essentials of an excellent barriComparative study on the apical sealing ability according to the obturation techniques