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Introduction: The esophagus and duodenum are rare sites of manifestation for extrapulmonary tuberculosis (TB). Its rarity makes the diagnosis challenging, especially when no other organ is involved, and the endoscopic findings may resemble malignancy. Case Presentation: We report a unique case of a 37-year-old woman who presented with dysphagia secondary to esophageal TB with an endoscopic appearance of a submucosal mass resembling malignancy. Conclusion: Esophageal TB is a rare cause of dysphagia, especially in a western setting. It should always be considered as a potential etiology in patients with dysphagia.

This study describes a unique case of single mucin-rich brain metastasis in a patient with breast cancer, mimicking the T2-fluid attenuation inversion recovery (FLAIR) mismatch sign and masquerading as an isocitrate dehydrogenase-mutant astrocytoma. This case highlights the importance of considering mucin-rich lesions in the differential diagnosis of intracranial tumors exhibiting T2-FLAIR mismatch. Clinicians must recognize the potential convergence in imaging characteristics between these metastases and gliomas to guarantee prompt and accurate patient care.

Abstract Tactile function is essential for human life as it enables us to recognize texture and respond to external stimuli, including potential threats with sharp objects that may result in punctures or lacerations. Severe skin damage caused by severe burns, skin cancer, chemical accidents, and industrial accidents damage the structure of the skin tissue as well as the nerve system, resulting in permanent tactile sensory dysfunction, which significantly impacts an individual’s daily life. Here, we introduce a fully-implantable wireless powered tactile sensory system embedded artificial skin (WTSA), with stable operation, to restore permanently damaged tactile function and promote wound healing for regenerating severely damaged skin. The fabricated WTSA facilitates (i) replacement of severely damaged tactile sensory with broad biocompatibility, (ii) promoting of skin wound healing and regeneration through collagen and fibrin-based artificial skin (CFAS), and (iii) minimization of foreign body reaction via hydrogel coating on neural interface electrodes. Furthermore, the WTSA shows a stable operation as a sensory system as evidenced by the quantitative analysis of leg movement angle and electromyogram (EMG) signals in response to varying intensities of applied pressures.

This paper proposes a novel pixel circuit and driving scheme that adopts low-temperature polycrystalline silicon and oxide thin-film transistors (LTPO TFTs) for mobile devices using active-matrix organic light-emitting diode (AMOLED) displays. The proposed pixel circuit and driving scheme provide uniform luminance and render flicker invisible at variable refresh rates (VRRs) from 1 to 120 Hz. Using the proposed pixel circuit with extended compensation time (tCOMP) improves the luminance uniformity at a high-frame rate. The proposed driving scheme applies a voltage to the driving TFTs (D-TFTs) higher than the programmed data voltage during the skip frame. This reduces the flicker caused by the hysteresis of D-TFTs during low-frame rate driving. A 6.0-inch quad high-definition (QHD) LTPO-based AMOLED display was fabricated using the new pixel circuit and driving scheme. Experimental results of the proposed pixel circuit show that the standard deviation of luminance was reduced from 0.056 to 0.008 by extending tCOMP from 2 to 8 µs. The flicker level was −51 dB, so there was no visual artifact during 1 Hz driving. A flicker-free LTPO-based AMOLED display with low power consumption is possible; driving can proceed in 1–120 Hz range.

Abstract In active matrix organic light emitting diode (AMOLED) displays, when a variable refresh rate is applied and the frame rate changes, the image’s color and luminance quality in AMOLED displays deteriorates. The frequency-dependent cognitive differences were experimentally demonstrated by using 6.76″ AMOLED displays. This phenomenon is dependent on the emission time and the data programming time on the frame rate. This degradation of the image quality during the frequency switch could be prevented by applying a variable initial voltage (VINI) to the OLED anode. For a frequency change between 60 and 120 Hz, the measured just noticeable color difference (JNCD) decreased from 7.50 to less than 1.00 in luminance, and from 2.34 to 0.02 in color. As our approach can prevent image quality distortion by utilizing an existing compensation pixel structure without additional compensation steps, it will be a promising technique for improving the picture quality in AMOLED displays.

We proposed a new channel edge doping (CED) technique for hump reduction in n-type low-temperature polycrystalline silicon (LTPS) thin-film transistors (TFTs) and validated it through experiments and technology computer-aided design (TCAD) simulations. The TCAD simulations indicate that the hump effect in LTPS TFTs is due to the high electron (e−) concentration (∼1016 cm−3) induced by an enhanced electric field (e-field) at the channel edge region along the width direction. In order to reduce the hump effect, we focused on decreasing the e− concentration at the channel edge. The CED process led to the selective control of the e− concentration at the channel edge. The decrease in the maximum e− concentration from 3.4 × 1016 to 2.9 × 1014 cm−3 at the channel edge using CED led to an effective reduction in the hump characteristic of LTPS TFTs. Furthermore, the CED process does not require any additional masks and is highly effective in hump reduction, rendering it beneficial for manufacturing active-matrix organic light-emitting diode displays.

Abstract Demand for increased scalability of oxide thin‐film transistors (TFTs) continues to rise, along with the need for ever‐higher integration densities and driving currents. However, the undesirable channel length (LCH)‐dependency renders short channels difficult. To overcome such behavior in back‐channel etched devices, back‐channel interface engineering using commercially favorable silicon oxide (SiOx) and the effects thereof on the electrical characteristics of fully integrated TFTs are investigated. Process‐dependent investigation reveals that a sequential formation of double‐layered SiOx with a defect control layer (DCL) effectively alleviates back‐channel damage. The proposed method imparts advanced functionality to conventional materials of SiOx. The DCL promotes oxygen inter‐diffusion to the oxygen‐deficient back‐channel, suppresses excess hydrogen inflow, and boosts out‐diffusion of residual copper from the back‐channel. This afforded excellent device uniformity and electrical characteristics with the proposed device, including field effect mobility of ≈14.0 ± 1.0 cm2 V−1 s−1, threshold voltage (Vth) of ≈1.22 ± 0.39 V, and subthreshold gate swing of ≈0.46 ± 0.09 V dec−1 at W/L = 4/7 µm. Furthermore, Vth variation when LCH decreased from 20 to 4 µm is dramatically suppressed from >11.39 V with the pristine device to 0.78 V with the proposed device, because of controlled back‐channel properties providing sufficient effective LCH.

The principal causes of the poor picture quality on active matrix organic light-emitting diode (AMOLED) displays, operating under extremely low brightness and gray-scale conditions, were analyzed and verified by measuring and modelling of the electrical simulations. Through the analysis, it was found that the deteriorated picture quality was induced by a delayed saturation voltage, which means the electric potential difference between the initial voltage applied to the anode of the OLED (Vinit) and the OLED saturated voltage (Vsat) for emission. This is because the deviations of pico-ampere-level currents and delayed OLED charging prior to light emission increased the saturation voltage when there were low driving currents. Thus, we optimized the voltage by increasing Vinit from −4.5 to −2.7 V, effectively eliminating image deterioration by reducing the OLED charging delay. Thus, the proposed approach opens up advancements of obtaining superior picture quality with ultra-low luminance, even in the dark illuminance environments. We discuss how OLED picture quality may be enhanced under low brightness, including the driving methods, design considerations, and processes involved.

Based on the movement and accumulation of ions in the 1-ethyl-3-methylimidazolium dicyanamide ([EMIM]DCA) electrolyte under a positive gate bias, the electrical double layer (EDL) was formed between a nanomesh channel and the [EMIM]DCA electrolyte to contribute to the increase in the conductance of the channel. The basic functions of artificial synapses, such as excitatory postsynaptic current (EPSC), paired pulse facilitation (PPF), short-term plasticity (STP), and long-term plasticity (LTP), are realized successfully. Besides, the high-pass filter function was implemented, which shows the application potential of the device in signal processing.

Here, the authors report the realization of an active pixel image sensor array composed by 64 pairs of switching transistors and phototransistors, based on wafer-scale bilayer MoS2. The device exhibits sensitive photoresponse under RGB light illumination, showing the potential of 2D MoS2 for image sensing applications.

We used a pulsed green laser to activate indium gallium zinc oxide thin-film transistors (IGZO TFTs). The IGZO films with large bandgaps (>3 eV) were easily activated by heat delivered by a pulsed green laser to the gate, source, and drain metal electrodes. The IGZO TFTs were quickly and selectively activated in the absence of conventional annealing. Compared to the IGZO TFTs that were annealed at 300°C, the IGZO TFTs that were activated via pulsed green laser irradiation exhibited superior electrical characteristics: a field effect mobility of 11.98 ± 0.64 cm2 V−1 s−1, a subthreshold swing of 0.33 ± 0.02 V dec−1, and an on/off ratio of 8.28 × 109 ± 7.42 × 109, which were attributable to increases in the number of metal–oxide (M-O) bonds and oxygen vacancies, and reduced levels of OH-related species. The pulsed green laser broke weak chemical M-O bonds in the IGZO films through dihydroxylation of the OH-related species, and then strengthened the residual M-O bonds via heat transfer from the metal electrodes. This new activation process could replace conventional annealing and is expected to expand the applications of flexible and transparent devices.

In this research, the use of indium gallium zinc oxide (IGZO) thin-film transistors (TFTs) with a porous oxide layer (POL) resulting from the mechanochemical treatment of spin-coated oxide films is suggested for the detection of visible light. Mechanochemical treatment is a new technique that uses cellophane tape to induce the selective formation of hydrophobic dots on the surface of the a-IGZO. These dots interfere with the deposition of the film during spin coating, resulting in pore formation. The IGZO TFT with a POL exhibits 341.32 A/W photoresponsivity, 1.10 × 106 photosensitivity, and 4.54 × 1010 Jones detectivity under 532 nm light illumination.

Nitrocellulose is proposed as a passivation layer for multilayer molybdenum disulfide (MoS2) thin-film transistors (TFTs) to improve the stability of the devices. After the devised passivation layer was stacked, the threshold voltage shift of the nitrocellulose-passivated MoS2 TFT after the positive-bias temperature stress tests decreased from 11.43 to 4.80 V. This enhanced stability was the result of the protection of the MoS2 channel from external reactive molecules like H2O, O2, and others in the atmosphere. Not only the stability was improved; the electrical performance was also enhanced. The field effect mobility and on/off ratio increased 1.13 and 3.05 times, respectively, due to the narrowed width of the Schottky barrier from the interfacial dipoles between the nitrocellulose and the MoS2 layers. Additionally, the formation of Mo-N bonding generated deep-level subgap states into the bandgap, which led to a higher probability of photoexcitation. Therefore, the MoS2 TFT with a nitrocellulose passivation layer exhibited 202.35 A/W enhanced photoresponsivity, 1.83 × 103 photosensitivity, and 9.94 × 109 Jones detectivity under 635 nm light at 10 mW/mm2.

Photolithography is an established microfabrication technique but commonly uses costly shortwavelength light sources to achieve high resolution. Here the authors use metal patterns embedded in a flexible elastomer photomask with mechanical robustness for generation of subdiffraction patterns as a cost effective near-field optical printing approach.

In this research, glucose was adopted as the switching layer of resistive random access memory (RRAM) for transient electronics. The fabricated glucose-based RRAM showed bipolar switching behavior with stable endurance (100 cycles) and retention (104 seconds) characteristics, without significant degradation, demonstrating its stable data storage capability and reliability. To investigate the switching mechanism of the glucose-based RRAM, various organic materials were prepared for the switching layer of RRAM. In addition, the dissolution characteristic of the glucose-based RRAM was evaluated to investigate the feasibility of its utilization for transient electronics, using a water-soluble substrate: a sodium carboxymethyl cellulose film. With this approach, a biocompatible glucose-based RRAM was successfully fabricated for future transient electronics.

A novel organic material named ‘collodion’ was suggested as a gate insulator for amorphous indium gallium zinc oxide thin-film transistors (a-IGZO TFTs). To find the optimized condition of the collodion gate insulator (CGI), the following three parameters of collodion solution were controlled: (1) the concentration of collodion solution; (2) the number of stacked layers; and (3) the spin-coating speed. The single-layered diluted CGI (collodion:ethanol=1:1) that was fabricated with a 3 krpm spin-coating speed exhibited an acceptable dielectric strength (J

Skin aging induced by ultraviolet (UV) irradiation increases expression of matrix metalloproteinase-1 (MMP-1) and destroys collagen fibers, as a result accelerating wrinkle formation. Natural products have been received scientific attention as utilized agents against photoaging. The aim of this study was to investigate the protective effect of Adenocaulon himalaicum Edgew. extract (AHE) against ultraviolet B (UVB)-induced skin damage, and to explain the underlying mechanisms in human dermal fibroblasts and epidermal keratinocytes. AHE effectively protects skin photoaging by preventing collagen degradation through MMP-1 inhibition via the MAPK/AP-1 signaling pathway. AHE significantly increased the expression of skin hydration factors, such as filaggrin, involucrin, loricrin, and caspase-14. To find how AHE possesses a direct impact on cellular activities, we identified neochlorogenic acid as a bioactive component of AHE for the first time. Neochlorogenic acid showed the anti-photoaging effect through ameliorating UVB-induced collagen degradation, reinforcing the skin barrier. Like the AHE-regulating mechanism, neochlorogenic acid modulates the MAPK/AP-1 signaling pathway and skin hydration factors. Taken together, these results suggest that AHE and neochlorogenic acid are well-qualified candidate for enhancing the conditions of photoaged skin.

Taurine is ubiquitously distributed in mammalian tissues and is highly concentrated in the heart, brain, and leukocytes. Taurine exerts neuroprotective effects in various central nervous system diseases and can suppress infarct formation in stroke. Taurine reacts with myeloperoxidase (MPO)-derived hypochlorous acid (HOCl) to produce taurine chloramine (Tau-Cl). We investigated the neuroprotective effects of taurine using a rat middle cerebral artery occlusion (MCAO) model and BV2 microglial cells. Although intranasal administration of taurine (0.5 mg/kg) had no protective effects, the same dose of Tau-Cl significantly reduced infarct volume and ameliorated neurological deficits and promoted motor function, indicating a robust neuroprotective effect of Tau-Cl. There was neutrophil infiltration in the post-MCAO brains, and the MPO produced by infiltrating neutrophils might be involved in the taurine to Tau-Cl conversion. Tau-Cl significantly increased the levels of antioxidant enzymes glutamate–cysteine ligase, heme oxygenase-1, NADPH:quinone oxidoreductase 1, and peroxiredoxin-1 in BV2 cells, whereas taurine slightly increased some of them. Antioxidant enzyme levels were increased in the post-MCAO brains, and Tau-Cl further increased the level of MCAO-induced antioxidant enzymes. These results suggest that the neutrophils infiltrate the area of ischemic injury area, where taurine is converted to Tau-Cl, thus protecting from brain injury by scavenging toxic HOCl and increasing antioxidant enzyme expression.

Grain boundaries in polycrystalline materials may offer the opportunity to explore physical phenomena that do not normally occur within the crystal grains. Here, the authors show that twin boundaries in Bi2Te3works as an electron supply for the whole bulk material.

We report on the effects of the intense pulsed light (IPL) rapid annealing process and back-channel passivation on the solution-processed In-Ga-Zn-O (IGZO) thin film transistors (TFTs) array. To improve the electrical properties, stability and uniformity of IGZO TFTs, the oxide channel layers were treated by IPL at atmospheric ambient and passivated by photo-sensitive polyimide (PSPI). When we treated the IGZO channel layer by the IPL rapid annealing process, saturation field effect mobility and subthreshold swing (S.S.) were improved. And, to protect the back-channel of oxide channel layers from oxygen and water molecules, we passivated TFT devices with photo-sensitive polyimide. The IGZO TFTs on glass substrate treated by IPL rapid annealing without PSPI passivation showed the field effect mobility (μFE) of 1.54 cm2/Vs and subthreshold swing (S.S.) of 0.708 V/decade. The PSPI-passivated IGZO TFTs showed higher μFE of 2.17 cm2/Vs than that of device without passivation process and improved S.S. of 0.225 V/decade. By using a simple and fast intense pulsed light treatment with an appropriate back-channel passivation layer, we could improve the electrical characteristics and hysteresis of IGZO-TFTs. We also showed the improved uniformity of electrical characteristics for IGZO TFT devices in the area of 10 × 40 mm2. Since this IPL rapid annealing process could be performed at a low temperature, it can be applied to flexible electronics on plastic substrates in the near future.

Flexible and transparent conducting electrodes are essential for future electronic devices. In this study, we successfully fabricated a highly-interconnected metal-mesh structure (MMS) using a self-formable cracked template. The template—fabricated from colloidal silica—can be easily formed and removed, presenting a simple and cost-effective way to construct a randomly and uniformly networked MMS. The structure of the MMS can be controlled by varying the spin-coating speed during the coating of the template solution or by stacking of metal-mesh layers. Through these techniques, the optical transparency and sheet resistance of the MMS can be designed for a specific purpose. A double-layered Al MMS showed high optical transparency (~80%) in the visible region, low sheet resistance (~20 Ω/sq), and good flexibility under bending test compared with a single-layered MMS, because of its highly-interconnected wire structure. Additionally, we identified the applicability of the MMS in the case of practical devices by applying it to electrodes of thin-film transistors (TFTs). The TFTs with MMS electrodes showed comparable electrical characteristics to those with conventional film-type electrodes. The cracked template can be used for the fabrication of a mesh structure consisting of any material, so it can be used for not only transparent electrodes, but also various applications such as solar cells, sensors, etc.

The high spatial resolution NO2 vertical column densities (VCDs) were measured from the airborne observations using the low-cost Hyperspectral Imaging Sensor (HIS) at three industrial areas (i.e., Chungnam, Jecheon, and Pohang) in Korea, where point sources (i.e., power plant, petrochemical complex, steel yard, and cement Kiln) with significant NO2 emissions are located. An innovative and versatile approach for NO2 VCD retrieval, hereafter referred to as the Modified Wavelength Pair (MWP) method, was developed to overcome the excessively variable radiometric and spectral characteristics of the HIS attributed to the absence of temperature control during the flight. The newly developed MWP method was designed to be insensitive to broadband spectral features, including the spectral dependency of surface and aerosol reflectivity, and can be applied to observations with relatively low spectral resolutions. Moreover, the MWP method can be implemented without requiring precise radiometric calibration of the instrument (i.e., HIS) by utilizing clean pixel data for non-uniformity corrections and is also less sensitive to the optical properties of the instrument and offers computational cost competitiveness. In the experimental flights using the HIS, NO2 plumes emitted from steel yards were particularly conspicuous among the various NO2 point sources, with peak NO2 VCD of 2.0 DU at Chungnam and 1.8 DU at Pohang. The typical NO2 VCD uncertainties ranged between 0.025-0.075 DU over the land surface and 0.10-0.15 DU over the ocean surface, and the discrepancy can be attributable to the lower signal-to-noise ratio over the ocean and higher sensitivity of the MWP method to surface reflectance uncertainties under low-albedo conditions. The NO2 VCDs retrieved from the HIS with the MWP method showed a good correlation with the collocated TROPOMI data (R=0.73, mean absolute error=0.106 DU). However, the temporal disparities between the HIS frames and the TROPOMI overpass, as well as the different observation geometries under complex vertical wind fields, limited the correlation. The comparison of TROPOMI and HIS NO2 VCD further demonstrated that the satellite sub-grid variability could be intensified near the point sources, with more than a threefold increase in HIS NO2 VCD variability (e. g., difference between 25th and 75th quantiles) over the TROPOMI footprints with NO2 VCD values exceeding 0.8 DU compared to footprints with NO2 VCD values below 0.6 DU. [ABSTRACT FROM AUTHOR]