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The effects of single event upset (SEU) by alpha particles and heavy ions on the data flip of a 3 nm technology node gate-all-around (GAA) nanosheet field-effect transistor (NSFET) 6T static random-access memory (SRAM) cell was studied through technology computer-aided design (TCAD) simulations. It was found that the sensitivity to radiation in the “off” pull-down transistor varies depending on the position of the alpha particle and heavy ions in the incident. The most significant radiation-induced increase in electron density occurs at the drain-channel junction. Heavy ion strikes lead to the lowest threshold linear energy transfer (LETth) value during the hold operation compared to read and write operations. The partial bottom dielectric isolation (PDI) scheme demonstrates lower radiation sensitivity than the conventional scheme, as the PDI layer acts as a physical barrier preventing charge migration from the substrate to the drain.

Total ionizing dose (TID) effects of gamma rays were investigated on DDR4 dynamic random access memory (DRAM) and analyzed using TCAD simulations. In this study, we considered the operating states, dose rates, temperatures, and annealing to analyze the impact of TID under different conditions. The worst degradation was observed in the operated state and at a low-dose rate because of the absence of an electrostatic barrier that reduced the possibility of interface trap formation under unbiased and high-dose rate conditions. At lower temperatures, the effects of radiation were mitigated by the reduced production of protons ( $\text{H}^{+}$ ). In addition, the unbiased DRAM and high-temperature conditions are the fastest to recover during post-irradiation annealing. In TCAD simulations, the retention time decreased with increasing temperature because the band-to-band tunneling (BTBT) generation increased. Furthermore, the retention time and row activation latency ( $t_{\mathrm {RCD}}$ ) degraded as the concentration of the interface traps increased. This is because the interface traps caused leakage currents and hindered the flow of electrons.

A novel memory cell transistor structure based on a saddle fin-based DRAM is presented for highly reliable operations. The overhang saddle fin (oss-fin) active structure is formed by two steps of etching of the fin; isotropic etching for the short side and anisotropic etching for the long side of the fin. The overhang sidewall fin structure results in the increase of retention time, decrease of isolation leakage current, increase of rowhammering tolerance, and increase of programming efficiency. A Technology Computer-Aided Design (TCAD) simulation study compares the overhang and the conventional saddle fin (s-fin) in terms of those reliability parameters. A lowered electric field underneath the storage node, a lowered passing gate coupling capacitance, and an elongated isolation leakage path are attributed to the reliability enhancements in the overhang saddle fin.

Memristive stateful logic for Boolean computers and memristive neural networks for neuromorphic computers are two distinct emerging applications enabled by memristors in future computing. Interestingly, they both utilize an identical crossbar array platform, suggesting their simultaneous implementation is possible. Herein, a new methodology combining the two technologies to create synergy in neuromorphic computing is proposed. A genetic algorithm in the memristive neural network is introduced, where the stochastic stateful logic realizes the required mutation and crossover operators. Under optimized genetic evolution conditions with the fittest selection algorithm, without any backpropagation circuits, the modified national institute of standards and technology dataset recognition accuracy of 90.1% for a 784 × 100 size network is anticipated, which is comparable to 93.9% accuracy using a conventional deep neural network.

In the modern electronic warfare signal environment, multiple radar signals of high density are mixed and received, and separating them into signals for each emitter is an essential step for emitter identification. Each radar has its own pulse repetition interval (PRI), which is a key parameter for deinterleaving pulse trains. The PRI is modulated in various forms depending on the purpose of the radar operation, and analyzing the mean PRI and the modulation type of PRI is the core of electronic warfare signal processing. Many existing papers have tried separate independent approaches for deinterleaving and for PRI modulation recognition. However, many distortions are unintentionally generated in the process of extracting the pulse train using the PRI estimated through deinterleaving for the PRI modulation recognition. This degrades the modulation recognition performance. In this paper, we propose a unified method for the deinterleaving and PRI modulation recognition of radar pulses using deep learning-based multitasking learning. The simulation results demonstrate the good performance of the proposed method for deinterleaving and modulation recognition, compared to the conventional method, and prove that the proposed method is robust in noisy radar signal environments.

Background The effect of a forest therapy in a natural environment noted that the forest therapy induced a state of relaxation among workers, thereby decreasing cortisol levels and work-related stress. Objective The primary objective of this study is to determine the effects of the forest therapy for employees in the manufacturing industry on psychological stress responds, stress hormone and heart rate variability (HRV). The secondary objective is to determine the effects of the forest therapy for employees in the manufacturing industry on cytotoxic activity of natural killer (NK) cells, health-related quality of life and mood states compare to urban untreated and remained in urban environment. Methods Forty-two employees were recruited from a single workplace located in Incheon city, Republic of Korea. Participants were allocated to either an experimental group (n= 21), wherein they participated in the forest therapy and or a control group (n= 21), wherein they were given no treatment. Participants were assigned to these groups on a randomized, open-label basis. Pre and post-test measures of natural killer (NK) cell activity, salivary cortisol, heart rate variability (HRV), health-related quality of life, stress response, and mood states were taken for both groups. Results The results showed that participants who took part in the forest therapy showed greater physiological improvement when compared to those in the control group, as indicated by a significant increase in some HRV measures. The forest therapy also contributed to a significantly greater decrease in work-related stress symptoms and a significantly greater improvement in health-related quality of life and mood states compared to participants in the control group. Conclusions These results may suggest that the forest therapy could be an effective means of relaxation technique, reducing stress and leads to an increase in positive mood for employees in the manufacturing industry.

Abstract Background Asian traditional herbal remedies are typically a concoction of a major and several complementary herbs. While balancing out any adverse effect of the major herb, the complementary herbs could dilute the efficacy of the major herb, resulting in a suboptimal therapeutic effect of an herbal remedy. Here, we formulated Chung-Sang (CS) by collating five major herbs, which are used against inflammatory diseases, and tested whether an experimental formula composed of only major herbs is effective in suppressing inflammation without significant side effects. Methods The 50% ethanol extract of CS (eCS) was fingerprinted by HPLC. Cytotoxicity to RAW 264.7 cells was determined by an MTT assay and a flow cytometer. Nuclear NF-κB and Nrf2 were analyzed by western blot. Ubiquitinated Nrf2 was similarly analyzed following immunoprecipitation of Nrf2. Acute lung inflammation and sepsis were induced in C57BL/6 mice. The effects of eCS on lung disease were measured by HE staining of lung sections, a differential cell counting of bronchoalveolar lavage fluid, a myeloperoxidase (MPO) assay, a real-time qPCR, and Kaplan-Meier survival of mice. Results eCS neither elicited cytotoxicity nor reactive oxygen species. While not suppressing NF-κB, eCS activated Nrf2, reduced the ubiquitination of Nrf2, and consequently induced the expression of Nrf2-dependent genes. In an acute lung inflammation mouse model, an intratracheal (i.t.) eCS suppressed neutrophil infiltration, the expression of inflammatory cytokine genes, and MPO activity. In a sepsis mouse model, a single i.t. eCS was sufficient to significantly decrease mouse mortality. Conclusions eCS could suppress severe lung inflammation in mice. This effect seemed to associate with eCS activating Nrf2. Our findings suggest that herbal remedies consisting of only major herbs are worth considering.

Silicon displacement defects are caused by various effects. For instance, epitaxial crystalline silicon growth and ion implantation often result in defects induced by the fabrication process, whereas displacement damage is induced by terrestrial cosmic radiation. Clustered displacement damage reportedly reduces the on-state current (Ion) in ordinary MOSFETs. In the case of an extremely scaled device such as a nanosheet field-effect transistor (NS-FET), the impact of displacement defect size was analyzed on the basis of the NS dimensions related to the device characteristics. In this study, we investigated the effect of displacement defects on NS-FETs using technology computer-aided design; the simulation model included quantum transport effects. The geometrical conditions, temperatures, trap concentrations, and scattering models were considered as the variables for on-state current reduction.

Though memristors can potentially emulate neuron and synapse functionality, useful signal energy is lost to Joule heating. Here, the authors demonstrate neuro-transistors with a pseudo-memcapacitive gate that actively process signals via energy-efficient capacitively-coupled neural networks.

Abstract Background The aim of this study was to assess correlation between pain and degenerative bony changes on cone-beam computed tomography (CBCT) images of temporomandibular joints (TMJs). Methods Two hundred eighty-three temporomandibular joints with degenerative bony changes were evaluated. Pain intensity (numeric rating scale, NRS) and pain duration in patients with degenerative joint disease (DJD) were also analyzed. We classified condylar bony changes on CBCT into five types: osteophyte (Osp), erosion (Ero), flattening (Fla), subchondral sclerosis (Scl), and pseudocyst (Pse). Results Degenerative bony changes were the most frequent in the age groups of 10~19, 20–29, and 50~59 years. The most frequent pain intensity was “none” (NRS 0, 34.6%) followed by “annoying” (NRS 3–5, 29.7%). The most frequent condylar bony change was Fla (219 joints, 77.4%) followed by Ero (169 joints, 59.7%). “Ero + Fla” was the most common combination of the bony changes (12.7%). The frequency of erosion was directly proportional to NRS, but the frequency of osteophyte was inversely proportional. The prevalence of Ero increased from onset until 2 years and gradually decreased thereafter. The prevalence of Osp, Ero, and Pse increased with age. Conclusions Osp and Ero can be pain-related variables in degenerative joint disease (DJD) patients. “Six months to 2 years” may be a meaningful time point from the active, unstable phase to the stabilized late phase of DJD.

Abstract In this paper, we present a unique resistive switching (RS) mechanism study of Pt/TiO2/Pt cell, one of the most widely studied RS system, by focusing on the role of interfacial bonding at the active TiO2–Pt interface, as opposed to a physico-chemical change within the RS film. This study was enabled by the use of a non-conventional scanning probe-based setup. The nanoscale cell is formed by bringing a Pt/TiO2-coated atomic force microscope tip into contact with a flat substrate coated with Pt. The study reveals that electrical resistance and interfacial bonding status are highly coupled together. An oxygen-mediated chemical bonding at the active interface between TiO2 and Pt is a necessary condition for a non-polar low-resistance state, and a reset switching process disconnects the chemical bonding. Bipolar switching mode did not involve the chemical bonding. The nature of chemical bonding at the TiO2-metal interface is further studied by density functional theory calculations.

Field-effect transistor (FET)-based biosensors have garnered significant attention for their label-free electrical detection of charged biomolecules. Whereas conventional output parameters such as threshold voltage and channel current have been widely used for the detection and quantitation of analytes of interest, they require bulky instruments and specialized readout circuits, which often limit point-of-care testing applications. In this study, we demonstrate a simple conversion method that transforms the surface potential into an oscillating signal as an output of the FET-based biosensor. The oscillation frequency is proposed as a parameter for FET-based biosensors owing to its intrinsic advantages of simple and compact implementation of readout circuits as well as high compatibility with neuromorphic applications. An extended-gate biosensor comprising an Al2O3-deposited sensing electrode and a readout transistor is connected to a ring oscillator that generates surface potential-controlled oscillation for pH sensing. Electrical measurement of the oscillation frequency as a function of pH reveals that the oscillation frequency can be used as a sensitive and reliable output parameter in FET-based biosensors for the detection of chemical and biological species. We confirmed that the oscillation frequency is directly correlated with the threshold voltage. For signal amplification, the effects of circuit parameters on pH sensitivity are investigated using different methods, including electrical measurements, analytical calculations, and circuit simulations. An Arduino board to measure the oscillation frequency is integrated with the proposed sensor to enable portable and real-time pH measurement for point-of-care testing applications.

Lectin is an important protein in medical and pharmacological applications. Impurities in lectin derived from natural sources and the generation of inactive proteins by recombinant technology are major obstacles for the use of lectins. Expressing recombinant lectin with a tandem repeat structure can potentially overcome these problems, but few studies have systematically examined this possibility. This was investigated in the present study using three distinct forms of recombinant mannose-binding lectin from Bryopsis plumosa (BPL2)—i.e., the monomer (rD1BPL2), as well as the dimer (rD2BPL2), and tetramer (rD4BPL2) arranged as tandem repeats. The concentration of the inducer molecule isopropyl β-D-1-thiogalactopyranoside and the induction time had no effect on the efficiency of the expression of each construct. Of the tested constructs, only rD4BPL2 showed hemagglutination activity towards horse erythrocytes; the activity of towards the former was 64 times higher than that of native BPL2. Recombinant and native BPL2 showed differences in carbohydrate specificity; the activity of rD4BPL2 was inhibited by the glycoprotein fetuin, whereas that of native BPL2 was also inhibited by d-mannose. Our results indicate that expression as tandem repeat sequences can increase the efficiency of lectin production on a large scale using a bacterial expression system.

Lectins, characterized by their carbohydrate-binding ability, have extensive practical applications. However, their industrial use is limited due to impurity. Thus, quality-controlled production of recombinant lectin is necessary. In this study, the algal lectin BPL3 (Bryopsis plumosa lectin 3) was successfully produced using a bacterial expression system, BL21(DE3), with an artificial repeated structure (dimeric construct). Recombinant dimeric BPL3 (rD2BPL3) was confirmed by LC-MS/MS spectrometry. Expression efficiency was greater for the construct with the repeat structure (rD2BPL3) than the monomeric form (rD1BPL3). Optimal conditions for expression were 1 mM IPTG at 20 °C. Recombinant lectin was purified under denaturing conditions and refolded by the flash dilution method. Recombinant BPL3 was solubilized in 1× PBS containing 2 M urea. rD2BPL3 showed strong hemagglutination activity using human erythrocyte. rD2BPL3 had a similar sugar specificity to that of the native protein, i.e., to N-acetyl-glucosamine (GlcNAc) and N-acetyl-galactosamine (GalNAc). Glycan array results showed that recombinant BPL3 and native BPL3 exhibited different binding properties. Both showed weak binding activity to α-Man-Sp. Native BPL3 showed strong binding specificity to the alpha conformation of amino sugars, and rD2BPL3 had binding activity to the beta conformation. The process developed in this study was suitable for the quality-controlled large-scale production of recombinant lectins.

A resistive switching memory suitable for integration into textiles is demonstrated on a copper wire network. Starting from copper wires, a Cu/CuxO/Pt sandwich structure is fabricated. The active oxide film is produced by simple thermal oxidation of Cu in atmospheric ambient. The devices display a resistance switching ratio of 102 between the high and low resistance states. The memory states are reversible and retained over 107 seconds, with the states remaining nondestructive after multiple read operations. The presented device on the wire network can potentially offer a memory for integration into smart textile.