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A new gas sensor based on metal–oxide–semiconductor field-effect transistor was fabricated and characterized. The sensor has p-type channel, floating-gate, and control-gate formed horizontally so that various kinds of sensing material can be used in this basic sensing structure. As a sensing material in this letter, SnO\rm{x} was adopted to sense a target gas of NO{2}. Measured drain current was changed by 195% at a NO{2} gas concentration of 50 ppm. Sensing speed is <50~s at 180 C. [ABSTRACT FROM AUTHOR]

Low-frequency noise (LFN) characteristics have been studied in polycrystalline-\TiOx-based resistive random access memories (RRAMs). LFNs are proportional to \1/f in high-resistance state (HRS), but those in low-resistance state (LRS) are proportional to \1/f only in less than \sim100 Hz. The normalized noise power in HRS is around three orders of magnitude higher than that in LRS. Bias dependence of \1/f noise shows that the current conduction mechanisms from noise measurements are consistent with those from the current–voltage relationships in \TiOx-based unipolar RRAM devices. [ABSTRACT FROM PUBLISHER]

Predicting outcomes in pulmonary tuberculosis is challenging despite effective treatments. This study aimed to identify factors influencing treatment success and culture conversion, focusing on artificial intelligence (AI)-based chest X-ray analysis and Xpert MTB/RIF assay cycle threshold (Ct) values. In this retrospective study across six South Korean referral centers (January 1 to December 31, 2019), we included adults with rifampicin-susceptible pulmonary tuberculosis confirmed by Xpert assay from sputum samples. We analyzed patient characteristics, AI-based tuberculosis extent scores from chest X-rays, and Xpert Ct values. Of 230 patients, 206 (89.6%) achieved treatment success. The median age was 61 years, predominantly male (76.1%). AI-based radiographic tuberculosis extent scores (median 7.5) significantly correlated with treatment success (odds ratio [OR] 0.938, 95% confidence interval [CI] 0.895–0.983) and culture conversion at 8 weeks (liquid medium: OR 0.911, 95% CI 0.853–0.973; solid medium: OR 0.910, 95% CI 0.850–0.973). Sputum smear positivity was 49.6%, with a median Ct of 26.2. However, Ct values did not significantly correlate with major treatment outcomes. AI-based radiographic scoring at diagnosis is a significant predictor of treatment success and culture conversion in pulmonary tuberculosis, underscoring its potential in personalized patient management. [ABSTRACT FROM AUTHOR]

The use of Hf0.5Zr0.5O2 (HZO) films within hafnia‐based ferroelectric tunnel junctions (FTJ) presents a promising avenue for next‐generation non‐volatile memory devices. HZO exhibits excellent ferroelectric properties, ultra‐thinness, low power consumption, nondestructive readout, and compatibility with silicon devices. In this study, Mo/HZO/n+ Si devices are investigated, incorporating a 1 nm HfO2 dielectric layer at the top and bottom of the HZO ferroelectric layer. Comparing the FTJ device configurations, it is observed that the metal‐ferroelectric‐dielectric‐semiconductor (MFIS) outperforms the metal‐dielectric‐ferroelectric‐semiconductor (MIFS) in terms of ferroelectricity, displaying a high 2Pr value of ≈69 µC cm−2. Additionally, MFIS exhibits lower leakage current, higher tunneling electro‐resistance ratio, and a thin dead layer during short pulse switching, as confirmed through DC double sweeping of I−V characteristics. The modified half‐bias scheme demonstrates a maximum array size of 191 for MFIS, showcasing its superior performance over MIFS. Synaptic characteristics, including potentiation, depression, paired‐pulse facilitation, spike‐rate‐dependent plasticity, and excitatory postsynaptic current, are measured using MFIS, highlighting its outstanding ferroelectric properties. As a physical reservoir, the FTJ device implements 16 states of 4 bits in reservoir computing. Finally, pattern recognition using a deep learning neural network achieves high accuracy with using the Modified National Institute of Standards and Technology dataset. [ABSTRACT FROM AUTHOR]

Background and Objective: When multiple complex air pollutants are combined in real‐world settings, the reliability of estimating the effect of a single pollutant is questionable. This study aimed to investigate the combined effects of changes in air pollutants on small airway dysfunction (SAD). Methods: We analysed Korea National Health and Nutrition Examination Survey (KNHANES) V–VIII database from 2010 to 2018 to elucidate the associations between annual changes in air pollutants over a previous 5‐year period and small airway function. We estimated the annual concentrations of five air pollutants: NO2, O3, PM2.5, SO2 and CO. Forced expiratory flow between 25% and 75% of vital capacity (FEF25%–75%) <65% was defined as SAD. Using the quantile generalized‐Computation (g‐Computation) model, the combined effect of the annual changes in different air pollutants was estimated. Results: A total of 29,115 individuals were included. We found significant associations between SAD and the quartiles of annual changes in NO2 (OR = 1.10, 95% CI = 1.08–1.12), O3 (OR = 1.03, 95% CI = 1.00–1.05), PM2.5 (OR = 1.03, 95% CI = 1.00–1.05), SO2 (OR = 1.04, 95% CI = 1.02–1.08) and CO (OR = 1.16, 95% CI = 1.12–1.19). The combined effect of the air pollutant changes was significantly associated with SAD independent of smoking (OR = 1.31, 95% CI = 1.26–1.35, p‐value <0.001), and this trend was consistently observed across the entire study population and various subgroup populations. As the estimated risk of SAD, determined by individual‐specific combined effect models, increased and the log odds for SAD increased linearly. Conclusion: The combined effect of annual changes in multiple air pollutant concentrations were associated with an increased risk of SAD. [ABSTRACT FROM AUTHOR]

This study implements a highly uniform 3D vertically stack resistive random‐access memory (VRRAM) with a four‐layer contact hole structure. The fabrication process of a four‐layer VRRAM is demonstrated, and its physical and electrical properties are thoroughly examined. X‐ray photoelectron spectroscopy and transmission electron microscopy are employed to analyze the chemical distribution and physical structure of the VRRAM device. Multilevel capability, reliable endurance (>104 cycles), and retention (104 s) are successfully obtained. Synaptic memory plasticity, such as spike time‐dependent plasticity, spike rate‐dependent plasticity, excitatory post‐synaptic current, paired‐pulse facilitation, and long‐term potentiation and depression is presented. Finally, the vector‐matrix multiplication (VMM) operation is conducted on a 4 × 12 VRRAM array, according to the low resistance state ratio. It is ascertained that the accuracy drop, which can occur due to VMM error, can be limited to a decrease of less than 0.44% point. Utilizing the high‐density, multilevel, and biological characteristics of VRRAM, it is possible to implement high‐performance neuromorphic systems that require densely integrated synaptic devices. [ABSTRACT FROM AUTHOR]

Background: Sarcopenia is a risk factor for pneumonia in the elderly, and the timed up-and-go test (TUG) can be used as a screening tool for sarcopenia in this population. This study aimed to evaluate the association between TUG test results and future pneumonia or ventilator care. Materials and methods: From the National Health Insurance Service-Senior Cohort database, we identified 19,804 people without neurological diseases who underwent the TUG test in the National Screening Program for Transitional Ages at the age of 66 years during 2007–2008. Gait abnormality was defined as taking 10 s or longer to perform the TUG test. Pneumonia occurrence was defined using the International Classification of Diseases 10th Revision (ICD-10) code for pneumonia (J12–J18, J69), and ventilator care was defined by procedure codes (M5830, M5850, M5867, M5858, M5860, M5859) according to the Healthcare Common Procedure Coding system codes from 2007 to 2015. Results: The mean follow-up period was 7.4 years (standard error, SE 0.02). The incidence rates of pneumonia in the normal and slow TUG groups were 38 and 39.5/1000 person-years, respectively. The slow TUG group did not show a higher risk of pneumonia (adjusted hazard ratio [aHR], 1.042; 95% confidence interval [95% CI], 0.988–1.107]). Regarding ventilator care, the incidence was 4.7 and 5.2 cases per 1,000 person-years in the normal and slow TUG groups, respectively. Slow TUG groups also did not show an increased risk of ventilator occurrence (aHR, 1.136, [95% CI = 0.947–1.363]). Conclusion: The TUG test result was not associated with future pneumonia or ventilator care and may not be useful for predicting pneumonia in community-dwelling elderly individuals. Further studies are needed to identify additional functional tools for sarcopenia associated with future pneumonia occurrences. [ABSTRACT FROM AUTHOR]

Background & Aims: The association between nonalcoholic fatty liver disease (NAFLD) and pulmonary function remains elusive because of the heterogeneous spectrum and inaccurate diagnostic methods of NAFLD, and insufficient pulmonary function data. We conducted this study to identify the association between histological severity of NAFLD and pulmonary function. Methods: This study included patients ≥18 years old with baseline pulmonary function data between August 2014 and July 2019 within a biopsy‐evaluated prospective NAFLD cohort. Cross‐sectionally, pre‐/post‐bronchodilator spirometric data with diffusing capacity (DLCO) were compared according to histological severity of NAFLD in the various demographic and metabolic subgroups. Multivariable‐adjusted analysis revealed specific histological features associated with reduced pulmonary function. Results: In a total of 420 patients with biopsy‐proven NAFLD, pre‐/post‐bronchodilator forced vital capacities (FVCs; a percentage of the predictive value) were inversely correlated with histological severity of NAFLD. Conversely, pre‐bronchodilator forced expiratory volume in 1 second (FEV1)/FVC was positively correlated with NAFLD severity. Post‐bronchodilator FVC (%) decreased and DLCO/alveolar volume (VA) increased linearly with worsening histological severity of NAFLD in multivariable analysis. In particular, fibrosis stage remained a significant independent predictor of decreased post‐bronchodilator FVC (%) (β‐coefficient, 4.41; 95% confidence interval [−8.39, −0.43]; P =.031) even after adjusted for clinical variables, exclusively in age <65 years, female, never‐smoker and nonchronic obstructive pulmonary disease subgroups. Conclusions: Pulmonary function deteriorates with worsening histological severity of NAFLD, especially at the fibrosis stage. The common pathogenesis of reduced pulmonary function and NAFLD fibrosis progression should be further explored. [ABSTRACT FROM AUTHOR]

A simple design for a wideband bandpass filter is presented.A compact filter structure is achieved by placing a microstrip ring between two parallel coupling gaps. 3D electromagnetic simulation and measurement of the proposed filter validate its wideband characteristics. The proposed filter exhibits good insertion loss <1.2 dB and group delay variation <0.2 ns. Both simulated and measured results show good agreement. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:154-155, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25678 [ABSTRACT FROM AUTHOR]

Abstract: A study of the E–H mode transition was performed in Ar, O2, N2, and mixture gas inductively coupled plasma (ICP) from the measurement of the electron energy distribution function (EEDF). Changes of the EEDF and characteristics of the discharge on the E–H mode transition were discussed. At each E-mode, the measured EEDFs had different shapes depending on the gas type and pressure, while the EEDFs evolved into Maxwellian distribution with the E–H transition due to electron–electron collisions. This study was also focused on the transition ICP power when the discharge transits from E-mode to H-mode. As the ICP power increased in Ar discharge, the transition ICP power had minimum value at a particular pressure, while the transition ICP power was gradually increased with gas pressures in molecule gas discharge. The transition ICP power with gas mixing ratios was also studied in Ar/O2/N2 mixture gas discharge. [Copyright &y& Elsevier]

With the introduction of new anti-tuberculosis drugs, all-oral regimens with shorter treatment durations for multidrug-resistant tuberculosis have been anticipated. We aimed to investigate whether a new all-oral regimen was non-inferior to the conventional regimen including second-line anti-tuberculosis drugs for 20–24 months in the treatment of fluoroquinolone-sensitive multidrug-resistant tuberculosis. In this multicentre, randomised, open-label phase 2/3 non-inferiority trial, we enrolled men and women aged 19–85 years with multidrug-resistant tuberculosis confirmed by phenotypic or genotypic drug susceptibility tests or rifampicin-resistant tuberculosis by genotypic tests at 12 participating hospitals throughout South Korea. Participants with fluoroquinolone-resistant multidrug-resistant tuberculosis were excluded. Participants were randomly assigned (1:1) to two groups using a block randomisation, stratified by the presence of diabetes and cavitation on baseline chest radiographs. The investigational group received delamanid, linezolid, levofloxacin, and pyrazinamide for 9 months, and the control group received a conventional 20–24-month regimen, according to the 2014 WHO guidelines. The primary outcome was the treatment success rate at 24 months after treatment initiation in the modified intention-to-treat population and the per-protocol population. Participants who were "cured" and "treatment completed" were defined as treatment success following the 2014 WHO guidelines. Non-inferiority was confirmed if the lower limit of a 97·5% one-sided CI of the difference between the groups was greater than −10%. Safety data were collected for 24 months in participants who received a predefined regimen at least once. This study is registered with ClinicalTrials.gov , NCT02619994. Between March 4, 2016, and Sept 14, 2019, 214 participants were enrolled, 168 (78·5%) of whom were included in the modified intention-to-treat population. At 24 months after treatment initiation, 60 (70·6%) of 85 participants in the control group had treatment success, as did 54 (75·0%) of 72 participants in the shorter-regimen group (between-group difference 4·4% [97·5% one-sided CI –9·5% to ∞]), satisfying the predefined non-inferiority margin. No difference in safety outcomes was identified between the control group and the shorter-regimen group. 9-month treatment with oral delamanid, linezolid, levofloxacin, and pyrazinamide could represent a new treatment option for participants with fluoroquinolone-sensitive multidrug-resistant tuberculosis. Korea Disease Control and Prevention Agency, South Korea [ABSTRACT FROM AUTHOR]

Background: The standard treatment regimen for drug-sensitive tuberculosis (TB), comprising four companion drugs, requires a minimum duration of 6 months, and this lengthy treatment leads to poor adherence and increased toxicity. To improve rates of adherence, reduce adverse events, and lower costs, a simplified and shortened treatment regimen is warranted.Methods: This study is a multicenter, open-label randomized clinical trial of non-inferiority design that compares a new regimen with the conventional regimen for drug-sensitive pulmonary TB. The investigational group will use a regimen of high-dose rifampicin (30 mg/kg/day) with isoniazid and pyrazinamide, and the treatment will be maintained for 12 weeks after the achievement of negative conversion of sputum culture. The control group will be treated for 6 months with a World Health Organization-endorsed regimen consisting of isoniazid, rifampicin (10 mg/kg/day), ethambutol, and pyrazinamide. The primary endpoint is the proportion of unfavorable outcomes at 18 months after randomization. Secondary outcomes include time to unfavorable treatment outcome, time to culture conversion on liquid medium, treatment success rate at the end of treatment, proportion of recurrence at 18 months after randomization, time to recurrence after treatment completion, and adverse events of grade 3 or higher during the treatment. We predict a 10% unfavorable outcome for the control group, and 0% difference from the investigational group. Based on 80% verification power and a 2.5% one-sided significance level for a non-inferiority margin of 6%, 393 participants per group are required. Considering the 15% dropout rate, a total of 926 participants (463 in each group) will be recruited.Discussion: This study will inform on the feasibility of the treatment regimen using high-dose rifampicin with a shortened and individualized treatment duration for pulmonary TB.Trial Registration: ClinicalTrials.gov NCT04485156 . Registered on July 24, 2020. [ABSTRACT FROM AUTHOR]

Degree of expression of programmed death-ligand 1 (PD-L1) is related with Immune check point inhibitors (ICIs) response but it needs sufficient tumor tissue. There is unmet need for easily accessible and prognostic peripheral blood (PB) biomarkers. We investigated the application of serum peripheral lymphocyte count (PLC) as a predictive PB biomarker for ICI response in patients with NSCLC. We conducted a retrospective study and reviewed the patients with NSCLC who were treated with ICIs from April 1, 2016, to March 31, 2019. The PLC before and after 1 month of immunotherapy was collected. We evaluated the association between PLC and progression-free survival (PFS), overall survival (OS) and adverse events. A total of 231 patients were treated with ICIs for NSCLC. The median follow-up period was 4.7 months and the disease progressed in 138 patients (59.7%). Compared with the lowest quartile (Q1: the lowest 25%), the highest quartile (Q4: the highest 25%) of post-treatment PLC showed a significantly higher PFS (HR 0.28, 95% CI 0.16–0.52) and OS (HR 0.35, 95% CI 0.19–0.65) in the adjusted model. An association between adverse events and PLC was not observed. We revealed that an increased pre- and post-treatment PLC was associated with favorable PFS and OS with NSCLC patients treated with ICIs. PLC could be a helpful for ICI responses in NSCLC. [ABSTRACT FROM AUTHOR]

Abstract: We investigate the effects of the Co and Mn ratio on the structure, morphology, electrochemical properties, and thermal stability of Li[Ni0.52Co0.16+x Mn0.32−x ]O2 cathode materials. Li[Ni0.52Co0.16+x Mn0.32−x ]O2 (x =0, 0.08, 0.16) cathode materials are prepared via high temperature calcination of LiOH and coprecipitated [Ni0.52Co0.16+x Mn0.32−x ](OH)2 hydroxides. From an X-ray diffraction investigation, the prepared materials have a well ordered O3 type α-NaFeO2 layer structure . As the Co content (x) is increased, the initial discharge capacity increase slightly but it is accompanied by severe capacity fading during extensive cycling. Meanwhile, a small increase of Mn enhances the electrochemical stability at high temperature (55°C) as well as the thermal stability. Electrochemical impedance spectroscopy reveals that manganese substitution is effective to reduce the resistance during cycling due to stabilization of the host structure. [Copyright &y& Elsevier]

Background: The presence and progression of interstitial lung abnormalities (ILAs) is known to be associated with a decline of lung function and increased risk of mortality.Research Question: We aimed to elucidate the clinical course according to ILAs in patients with COPD.Study Design and Methods: A retrospective study was conducted between January 2013 and December 2018 of COPD patients who underwent chest CT imaging and longitudinal pulmonary function tests. We evaluated radiologic findings, history of acute exacerbations of COPD, and lung function changes during the longitudinal follow-up.Results: Of 363 patients with COPD, 44 and 103 patients had equivocal and definite ILAs, respectively. Patients with ILAs were significantly older and had lower FEV1 and FVC than patients without ILAs. During the mean follow-up period of 5.2 years, ILAs were associated significantly with the annual incidence of moderate to severe acute exacerbation of COPD (β ± SD, 0.38 ± 0.12; P = .002) and with the risk of frequent exacerbation (adjusted OR, 2.03; P = .045). Patients with progressive ILAs showed a significantly higher rate of annual decline in FEV1 and FVC than those showing no change in, or improved, ILAs.Interpretation: ILAs were associated significantly with moderate to severe acute exacerbation in patients with COPD, and the progression of ILAs was associated with an accelerated decline in lung function. [ABSTRACT FROM AUTHOR]

Objective: To investigate the incidence of tuberculosis (TB) in patients with rheumatic diseases receiving high-dose glucocorticoids and to evaluate the preventive effect of isoniazid (INH). Methods: This study included 1618 treatment episodes of prolonged (≥4 weeks), high-dose steroids (≥30mg/day of prednisone) in 1160 patients. Of these, INH was administered in 152 (9.4%) treatment episodes (INH group), while others received no prophylaxis (control group). The high-risk subgroup (n = 92) was defined as patients with 1) incomplete adherence to treatment of previous TB, 2) positive interferon-γ release assay, and/or 3) linear/reticular fibrotic lesions on chest radiographs. Primary outcome was 1-year incidence of TB in each group. Results: During 1579.8 person-years, 21 cases of TB occurred. The high-risk subgroup showed a significantly higher TB incidence than the non-high-risk subgroup (Incidence rate ratio = 8.29). INH did not significantly affect the 1-year TB incidence in the whole population but numerically reduced it only in the high-risk subgroup [adjusted hazards ratio = 0.37 (95% CI, 0.002–5.10)]. The incidence of adverse drug reactions (ADRs) related to INH was 111.6 (89.3–137.9)/100 person-years, including one fatal occurrence of fulminant hepatitis. The number needed to treat (NNT) to prevent one case of TB was lower than the number needed to harm (NNH) for one case of severe ADR only in the high-risk subgroup (11 vs. 16). Conclusion: INH treatment to prevent TB might be effective in high-risk patients but has a risk of frequent ADRs, which limits its use in general practice in patients not at a high risk of developing TB. [ABSTRACT FROM AUTHOR]

Background: There are limited data available on whether drug-induced hepatotoxicity (DIH) affects the clinical outcomes of tuberculosis (TB) treatment. We explored the effects of DIH on the clinical course and outcomes of pulmonary TB.Methods: In this retrospective cohort study, we included patients with culture-proven pulmonary TB treated in a tertiary hospital from 2013 to 2016. DIH was defined as proposed by the official American Thoracic Society statement. We compared the clinical outcomes of DIH and non-DIH patients.Results: Between January 1, 2013 and December 31, 2016, a total of 168 TB patients were included, and 20 (11.9%) were diagnosed with DIH. These patients were significantly older, had a higher Charlson Comorbidity Index score, exhibited more chronic liver disease, included more chronic alcoholics, and had a lower body mass index than non-DIH patients. We found no significant differences between DIH and non-DIH patients in the 2-month sputum culture conversion rate, the time to sputum culture conversion, treatment outcomes, or total treatment duration. However, the ratio of treatment interruption time to total treatment duration and the proportion of hepatotonic users were significantly higher among DIH patients.Conclusion: DIH development during TB treatment does not significantly affect the clinical outcomes of pulmonary TB. However, treatment interruption caused by DIH may increase the risks of future relapse and acquired resistance. Further study is needed. [ABSTRACT FROM AUTHOR]

• Corticosteroids in pneumonia associated with an increased risk of in-hospital MACEs. • The risk positively associated with duration and cumulative dose of corticosteroids. • The risk greater with more comorbidities and more severe pneumonia. Limited data are available concerning cardiovascular risk with respect to adjunctive corticosteroid use in patients with pneumonia. We aimed to assess the associations between systemic corticosteroid use and the occurrence of major adverse cardiovascular events (MACEs) in patients hospitalized for pneumonia. Among study participants enrolled via surveillance for severe acute respiratory infection from July 2016 to January 2017, the clinical course of patients with pneumonia was retrospectively investigated until December 2019. We evaluated the occurrence of in-hospital and after-discharge MACEs according to steroid use during hospitalization. Of the 424 patients hospitalized for pneumonia, 118 (28.8%) received systemic corticosteroids during hospitalization. The most common reason for steroid use was acute exacerbation of chronic lung disease (75.4%). Systemic steroid use was significantly associated with an increased risk of in-hospital MACEs; it was not associated with after-discharge MACEs. The risk of in-hospital MACEs was significantly greater in patients with more comorbidities, more severe pneumonia, and a higher inflammatory marker level; moreover, it was positively associated with duration and cumulative dose of steroid treatment. Systemic corticosteroid use was associated with an increased risk of in-hospital MACEs in patients hospitalized for pneumonia. [ABSTRACT FROM AUTHOR]

Abstract: A 5-W direct methanol fuel cell (DMFC) stack has been developed to investigate the dynamic behaviour of the performance. The stack generates the 5-W peak power with 10 cells of 3cm×3cm active area. Upon changing the load conditions, the transient behaviour of the stack voltage is monitored to evaluate the speed at which the stack adapts to the changes. The transient characteristics of the stack current are also studied with continuously changing fuel flow rates of 2M methanol solution and air. The optimum operating conditions for the stable operation of the 5-W DMFC stacks are reported. [Copyright &y& Elsevier]

• A CO gas sensor based on Si MOSFET technology is proposed. • Pt-decorated In 2 O 3 nanoparticles are formed as sensing layer by inkjet-printing method on FET-type platforms. • CO gas sensing performance is improved by catalytic Pt decoration. • The gas response and the recovery time of the sensor are greatly affected depending on the polarity of pulsed pre-bias. • Our sensors have reasonable selectivity for CO gas at 200 °C. This paper investigates carbon monoxide (CO) gas sensing performance in a silicon metal-oxide semiconductor field effect transistor (Si MOSFET)-based gas sensor having a structure in which a floating-gate (FG) and a control-gate (CG) are interdigitated in a horizontal direction. The sensing material, indium oxide (In 2 O 3) nanoparticles, is formed by an inkjet printing process between the FG covered with an insulator stack and exposed CG. Decorating the sensing layer with catalytic Pt and applying pulsed pre-bias are introduced as a method to improve CO gas sensing characteristics of the MOSFET sensor. First, CO gas sensing performance with Pt concentration and operating temperature is studied. The sensing performance is measured at 200 °C mainly by applying pulses to the CG. The response, response and recovery times of the MOSFET sensor are significantly enhanced with catalytic Pt decoration. In this work, 5% Pt decoration shows the best sensing characteristics. Response and recovery times are improved by 65% and 70%, by applying a pre-bias of 2 V and −2 V to the CG during response and recovery, respectively. [ABSTRACT FROM AUTHOR]

Background: Mucus plugs identified through chest computed tomography (CT) scans have emerged as potential prognostic factors in chronic obstructive pulmonary disease (COPD). This 5-year longitudinal study investigated their impact on exacerbations and FEV 1 decline., Methods: COPD patients with baseline chest CT and spirometric assessments were categorized based on mucus plug presence. Propensity-score matching yielded balanced groups. Exacerbation rates, time to exacerbation events, hazard ratio (HR) for exacerbations, and annual rates of FEV 1 decline were evaluated. Sensitivity analysis was performed with stratification according to mucus plug scores of 0, 1-2, and ≥3., Results: Among 623 eligible patients, the mucus plug group was 44.3%. Through 1:1 propensity-score matching, each group was comprised of 187 individuals with balanced covariates. The mucus plug group showed higher rates of moderate-to-severe (0.51/year vs. 0.58/year, P=0.035), severe exacerbations (0.21/year vs. 0.24/year, P=0.032), and non-eosinophilic exacerbations (0.45/year vs. 0.52/year, P=0.008). Mucus plugs were associated with increased hazard of moderate-to-severe (adjusted HR=1.502 [95% CI 1.116-2.020]), severe (adjusted HR=2.106 [95% CI, 1.429-3.103]), and non-eosinophilic exacerbations (adjusted HR=1.551 [95% CI, 1.132-2.125]). Annual FEV 1 decline was accelerated in the mucus plug group (β-coefficient=-62 [95% CI, -120 to -5], P=0.035). Sensitivity analysis showed higher risk of exacerbations and accelerated FEV 1 decline in mucus plug score ≥3 compared to score 0., Conclusions: Mucus plugs are associated with increased risks of exacerbations, particularly non-eosinophilic, and accelerated FEV 1 declines over 5 years. Our study identified the potential prognostic value of mucus plugs on future exacerbation risks and lung function decline trajectories., (Copyright © 2024 SEPAR. Published by Elsevier España, S.L.U. All rights reserved.)

Objective: We aimed to elucidate the clinical factors associated with acute exacerbation and disease progression in young patients with chronic obstructive pulmonary disease (COPD)., Methods: This retrospective longitudinal observational study included patients with COPD aged between 20 and 50 years with post-bronchodilator forced expiratory volume in one second (FEV 1 )/forced vital capacity (FVC)<0.7. Eligible patients were followed up with ≥2 spirometry examinations at 1 year interval after COPD diagnosis. The primary outcome was moderate-to-severe acute exacerbation in young patients with COPD. Secondary outcomes were early initiation of regular inhalation therapy and accelerated annual post-bronchodilator FEV 1 decline., Results: A total of 342 patients were followed up during a median of 64 months. In multivariable analyses, risk factors for moderate-to-severe exacerbation were history of asthma (adjusted HR (aHR)=2.999, 95% CI=[2.074-4.335]), emphysema (aHR=1.951, 95% CI=[1.331-2.960]), blood eosinophil count >300/µL (aHR=1.469, 95% CI=[1.038-2.081]) and low FEV 1 (%) (aHR=0.979, 95% CI=[0.970-0.987]). A history of asthma, sputum, blood eosinophil count >300/µL, low FEV 1 (%) and low diffusing capacity of the lung for carbon monoxide (DL CO ) (%) were identified as clinical factors associated with the early initiation of regular inhalation therapy. The risk factors associated with worsened FEV 1 decline were increasing age, female sex, history of pulmonary tuberculosis, sputum, low FEV 1 (%) and low DL CO (%)., Conclusions: In young COPD patients, specific high-risk features of acute exacerbation and disease progression need to be identified, including a history of previous respiratory diseases, current respiratory symptoms, blood eosinophil counts, and structural or functional pulmonary impairment., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: There is limited data regarding the clinical outcomes of clonal hematopoiesis of indeterminate potential (CHIP) in patients with chronic obstructive pulmonary disease (COPD). This study aimed to evaluate the clinical significance of CHIP as a COPD biomarker., Methods: This retrospective study was conducted on patients with COPD who were enrolled prospectively in the Seoul National University Hospital Airway Registry from January 2013 to December 2019 and underwent pulmonary function and blood tests. We evaluated the CHIP score according to smoking status and severity of airflow obstruction., Results: We analyzed next-generation sequencing data to detect CHIP in 125 patients with COPD. Current smokers had a higher prevalence of CHIP in combination of DNMT3A, TET2, and PPM1D (DTP), DNA methyltransferase 3 alpha (DNMT3A), and protein phosphatase, Mg2+/Mn2+ dependent 1D (PPM1D) genes than in never- or ex-smokers. CHIP of DTP and DNMT3A genes was significantly associated with current smokers (adjusted odds ratio [aOR], 2.80; 95% confidence interval [CI], 1.01 to 7.79) (aOR, 4.03; 95% CI, 1.09 to 14.0). Patients with moderate-to-severe airflow obstruction had a higher prevalence of CHIP in most of the explored genes than those with mild obstruction, although the difference was not statistically significant. CHIP in ASXL transcriptional regulator 1 (ASXL1) genes was significantly associated with history of mild, severe, and total acute exacerbation., Conclusion: Given that CHIP in specific genes was significantly associated with current smoking status and acute exacerbation, CHIP can be considered as a candidate biomarker for COPD patients.

Background and Objective: When multiple complex air pollutants are combined in real-world settings, the reliability of estimating the effect of a single pollutant is questionable. This study aimed to investigate the combined effects of changes in air pollutants on small airway dysfunction (SAD)., Methods: We analysed Korea National Health and Nutrition Examination Survey (KNHANES) V-VIII database from 2010 to 2018 to elucidate the associations between annual changes in air pollutants over a previous 5-year period and small airway function. We estimated the annual concentrations of five air pollutants: NO 2 , O 3 , PM 2.5 , SO 2 and CO. Forced expiratory flow between 25% and 75% of vital capacity (FEF 25%-75% ) <65% was defined as SAD. Using the quantile generalized-Computation (g-Computation) model, the combined effect of the annual changes in different air pollutants was estimated., Results: A total of 29,115 individuals were included. We found significant associations between SAD and the quartiles of annual changes in NO 2 (OR = 1.10, 95% CI = 1.08-1.12), O 3 (OR = 1.03, 95% CI = 1.00-1.05), PM 2.5 (OR = 1.03, 95% CI = 1.00-1.05), SO 2 (OR = 1.04, 95% CI = 1.02-1.08) and CO (OR = 1.16, 95% CI = 1.12-1.19). The combined effect of the air pollutant changes was significantly associated with SAD independent of smoking (OR = 1.31, 95% CI = 1.26-1.35, p-value <0.001), and this trend was consistently observed across the entire study population and various subgroup populations. As the estimated risk of SAD, determined by individual-specific combined effect models, increased and the log odds for SAD increased linearly., Conclusion: The combined effect of annual changes in multiple air pollutant concentrations were associated with an increased risk of SAD., (© 2024 Asian Pacific Society of Respirology.)

Higher functionality should be achieved within the device-level switching characteristics to secure the operational possibility of mixed-signal data processing within a memristive crossbar array. This work investigated electroforming-free Ta/HfO 2 /RuO 2 resistive switching devices for digital- and analog-type applications through various structural and electrical analyses. The multiphase reset behavior, induced by the conducting filament modulation and oxygen vacancy generation (annihilation) in the HfO 2 layer by interacting with the Ta (RuO 2 ) electrode, was utilized for the switching mode change. Therefore, a single device can manifest stable binary switching between low and high resistance states for the digital mode and the precise 8-bit conductance modulation (256 resistance values) via an optimized pulse application for the analog mode. An in-depth analysis of the operation in different modes and comparing memristors with different electrode structures validate the proposed mechanism. The Ta/HfO 2 /RuO 2 resistive switching device is feasible for a mixed-signal processable memristive array.

Background: Different progressions or prognoses of chronic obstructive pulmonary disease (COPD) have been reported according to structural abnormalities based on chest computed tomography (CT). This study aimed to investigate whether different structural abnormalities independently affect annual lung function changes and clinical prognosis in patients with COPD., Methods: This longitudinal multicenter observational study was conducted using the KOCOSS cohort (NCT02800499) database in Korea from January 2012 to December 2019. For COPD patients with chest CT findings at baseline enrolment and longitudinal spirometric data, annual forced expiratory volume in 1 s (FEV 1 ) decline rate (mL/year) and clinical outcomes were compared according to structural abnormalities, including emphysema, bronchiectasis (BE), and tuberculosis-destroyed lung (TDL). We estimated the adjusted annual FEV 1 changes using a mixed-effect linear regression model., Results: Among the enrolled 237 patients, 152 showed structural abnormalities. Emphysema, BE, and TDL were observed in 119 (78.3%), 28 (18.4%), and 27 (17.8%) patients, respectively. The annual decline in FEV 1 was faster in COPD patients with structural abnormalities than those without (β = -70.6 mL/year, P-value = 0.039). BE/TDL-dominant or emphysema-dominant structural abnormality contributed to an accelerated annual FEV 1 decline compared to no structural abnormality (BE/TDL-dominant, β = -103.7 mL/year, P-value = 0.043; emphysema-dominant, β = -84.1 mL/year, P-value = 0.018). Structural abnormalities made no significant differences in acute exacerbation rate and mortality., Conclusion: The lung function decline rate in COPD differed according to structural abnormalities on CT. These findings may suggest that more focus should be placed on earlier intervention or regular follow-up with spirometry in COPD patients with BE or TDL on chest CT., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Kwang Ha Yoo reports financial support was provided by 10.13039/501100003653Korea National Institute of Health. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Published by Elsevier Ltd.)

Background: Roflumilast is effective in reducing acute exacerbation in patients with chronic obstructive pulmonary disease (COPD) at high risk of severe exacerbation. Clinical traits related to the benefits of roflumilast need to be evaluated in patients with COPD., Methods: A longitudinal observational study in patients newly diagnosed with COPD was conducted using claims data from the Health Insurance Review and Assessment Service in South Korea from 2012-2020 after a 2-year washout period. The primary outcome was to estimate the ratio of hazard ratio (RHR) of roflumilast for moderate-to-severe exacerbation in prespecified subgroups. A time-dependent Cox regression model was used to estimate the hazard ratio (HR) for moderate-to-severe exacerbations., Results: Among 823,862 patients with COPD, 0.6% used roflumilast. The adjusted HR of roflumilast for moderate-to-severe exacerbations was reduced when treated for ≥3 months (RHR =0.558). Interaction effects of the variables on the HR of roflumilast for moderate-to-severe exacerbation were identified. The adjusted HR of roflumilast for moderate-to-severe exacerbation was significantly reduced in several subgroups: older age (65 years > age ≥50 years, RHR =0.838; age ≥65 years, RHR =0.818), a higher Charlson comorbidity index (1, RHR =0.832; 2, RHR =0.798; ≥3, RHR =0.790), history of exacerbation (RHR =0.886), bronchiectasis (RHR =0.774), chronic bronchitis (RHR =0.793), inhaled therapy [mono-bronchodilator, RHR =0.824; inhaled corticosteroid (ICS)/long-acting beta-agonist (LABA), RHR =0.591; LABA/long-acting muscarinic antagonist (LAMA), RHR =0.822; ICS/LABA/LAMA, RHR =0.570], methylxanthine (RHR =0.853), and statin (RHR =0.888)., Conclusions: The benefit of roflumilast in moderate-to-severe exacerbations was estimated to be greater in specific subgroups of patients with COPD. Personalised approaches to roflumilast based on clinical phenotypes would be effective for COPD., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jtd.amegroups.com/article/view/10.21037/jtd-23-1129/coif). C.K.R. serves as an unpaid editorial board member of Journal of Thoracic Disease. The other authors have no conflicts of interest to declare., (2024 Journal of Thoracic Disease. All rights reserved.)

Background: Preserved ratio impaired spirometry (PRISm) is a heterogeneous disease entity. Limited data are available regarding its prevalence, clinical course, or prognosis. We aimed to evaluate the longitudinal clinical course of patients with PRISm compared with chronic obstructive pulmonary disease (COPD)., Methods: A retrospective study enrolled PRISm and COPD patients who underwent chest computed tomography and longitudinal pulmonary function tests between January 2013 and December 2020. We compared the incidence of acute exacerbations and lung function changes between PRISm and COPD patients., Results: Of the 623 patients, 40 and 583 had PRISm and COPD, respectively. Compared to COPD patients, PRISm patients were younger, more likely to be female and have a history of tuberculosis, and less likely to be smokers. They also had less severe comorbidities, lower forced vital capacity (FVC) and diffusing capacity of the lungs for carbon monoxide (D LCO ). The clinical course was not significantly different between the PRISm and COPD patients in terms of the risk of moderate-to-severe acute exacerbations or proportion of frequent exacerbators. During follow-up, PRISm patients had a significantly slower annual decline of forced expiratory volume in 1 second, FVC, and DL CO than COPD patients., Conclusion: PRISm patients had no significant difference in the risk of acute exacerbations, but a significantly slower decline of lung function during longitudinal follow-up, compared with COPD patients., Competing Interests: The authors report no potential conflicts of interest in this work., (© 2024 Yoon et al.)

This study presents findings indicating that the ferroelectric tunnel junction (FTJ) or resistive random-access memory (RRAM) in one cell can be intentionally selected depending on the application. The HfAlO film annealed at 700 °C shows stable FTJ characteristics and can be converted into RRAM by forming a conductive filament inside the same cell, that is, the process of intentionally forming a conductive filament is the result of defect generation and redistribution, and applying compliance current prior to a hard breakdown event of the dielectric film enables subsequent RRAM operation. The converted RRAM demonstrated good memory performance. Through current-voltage fitting, it was confirmed that the two resistance states of the FTJ and RRAM had different transport mechanisms. In the RRAM, the 1/f noise power of the high-resistance state (HRS) was about ten times higher than that of the low-resistance state (LRS). This is because the noise components increase due to the additional current paths in the HRS. The 1/f noise power according to resistance states in the FTJ was exactly the opposite result from the case of the RRAM. This is because the noise component due to the Poole-Frenkel emission is added to the noise component due to the tunneling current in the LRS. In addition, we confirmed the potentiation and depression characteristics of the two devices and further evaluated the accuracy of pattern recognition through a simulation by considering a dataset from the Modified National Institute of Standards and Technology., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

A weak correlation between diffusing capacity of the lung for carbon monoxide (DL CO ) and emphysema has been reported. This study investigated whether impaired DL CO in chronic obstructive pulmonary disease (COPD) is associated with increased risk of acute exacerbation independent of the presence or extent of emphysema. This retrospective cohort study included patients with COPD between January 2004 and December 2019. The participants were divided into four groups based on visually detected emphysema and impaired DL CO . Among 597 patients with COPD, 8.5% had no emphysema and impaired DL CO whereas 36.3% had emphysema without impaired DL CO . Among the four groups, patients with impaired DL CO and emphysema showed a higher risk of moderate-to-severe or severe exacerbation than those with normal DL CO . Impaired DL CO was an independent risk factor for severe exacerbation (hazard ratio, 1.524 [95% confidence interval 1.121-2.072]), whereas the presence of emphysema was not. The risk of moderate-to-severe or severe exacerbation increases with the severity of impaired DL CO . After propensity-score matching for the extent of emphysema, impaired DL CO was significantly associated with a higher risk of moderate-to-severe (p = 0.041) or severe exacerbation (p = 0.020). In patients with COPD and heterogeneous parenchymal abnormalities, DL CO can be considered an independent biomarker of acute exacerbation., (© 2024. The Author(s).)

Background: Global Lung Function Initiative (GLI)-2012 reference equation is currently suggested for interpretation of spirometry results and a new local reference equation has been developed in South Korea. However, lung function profiles according to the different reference equations and their clinical relevance have not been identified in chronic obstructive pulmonary disease (COPD) patients., Methods: Our cross-sectional study evaluated Choi's, Korean National Health and National Examination Survey (KNHANES)-VI, and GLI-2012 reference equations. We estimated the percentages of predictive forced expiratory volume in one second (FEV 1 ) and airflow limitation severity according to reference equations and analyzed their associations with patient reported outcomes (PROs): COPD assessment test (CAT) score, St. George's Respiratory Questionnaire for COPD patients (SGRQ-C) score, and six minute walk distance (6MWD)., Results: In the eligible 2,180 COPD patients, lower predicted values of FEV 1 and forced vital capacity (FVC) were found in GLI-2012 compared to Choi's and KNHANES-VI equations. GLI-2012 equation resulted in a lower proportion of patients being classified as FEV 1 < 80% or FVC < 80% compared to the other equations. However, the Z-scores of FEV 1 and FVC were similar between the KNHANES-VI and GLI-2012 equations. Three reference equations exhibited significant associations between FEV 1 (%) and patient-reported outcomes (CAT score, SGRQ-C score, and 6MWD)., Conclusion: GLI-2012 reference equation may not accurately reflect FEV 1 (%) in the Korean population, but the Z-score using GLI-2012 equation can be a viable option for assessing FEV 1 and airflow limitation in COPD patients. Similar to the other two equations, the GLI-2012 equation demonstrated significant associations with PROs., Competing Interests: The authors have no potential conflicts of interest to disclose., (© 2024 The Korean Academy of Medical Sciences.)

Background and Objectives: Few studies have reported which inhaled combination therapy, either bronchodilators and/or inhaled corticosteroids (ICSs), is beneficial in patients with bronchiectasis and airflow obstruction. Our study compared the efficacy and safety among different inhaled combination therapies in patients with bronchiectasis and airflow obstruction., Methods: Our retrospective study analyzed the patients with forced expiratory volume in 1 s (FEV 1 )/forced vital capacity < 0.7 and radiologically confirmed bronchiectasis in chest computed tomography between January 2005 and December 2021. The eligible patients underwent baseline and follow-up spirometric assessments. The primary endpoint was the development of a moderate-to-severe exacerbation. The secondary endpoints were the change in the annual FEV 1 and the adverse events. Subgroup analyses were performed according to the blood eosinophil count (BEC)., Results: Among 179 patients, the ICS/long-acting beta-agonist (LABA)/long-acting muscarinic antagonist (LAMA), ICS/LABA, and LABA/LAMA groups were comprised of 58 (32.4%), 52 (29.1%), and 69 (38.5%) patients, respectively. ICS/LABA/LAMA group had a higher severity of bronchiectasis and airflow obstruction, than other groups. In the subgroup with BEC ≥ 300/uL, the risk of moderate-to-severe exacerbation was lower in the ICS/LABA/LAMA group (adjusted HR = 0.137 [95% CI = 0.034-0.553]) and the ICS/LABA group (adjusted HR = 0.196 [95% CI = 0.045-0.861]) compared with the LABA/LAMA group. The annual FEV 1 decline rate was significantly worsened in the ICS/LABA group compared to the LABA/LAMA group (adjusted β-coefficient=-197 [95% CI=-307--87]) in the subgroup with BEC < 200/uL., Conclusion: In patients with bronchiectasis and airflow obstruction, the use of ICS/LABA/LAMA and ICS/LABA demonstrated a reduced risk of exacerbation compared to LABA/LAMA therapy in those with BEC ≥ 300/uL. Conversely, for those with BEC < 200/uL, the use of ICS/LABA was associated with an accelerated decline in FEV 1 in comparison to LABA/LAMA therapy. Further assessment of BEC is necessary as a potential biomarker for the use of ICS in patients with bronchiectasis and airflow obstruction., (© 2024. The Author(s).)

This study presents a preliminary exploration of thermally oxidized TaOx-based memristors and their potential as artificial synapses. Unlike the 10-min annealed devices, which display instability due to current overshoots, the 5-min annealed device exhibits stable resistive switching, retention, and endurance characteristics. Moreover, our memristor showcases synaptic behaviors encompassing potentiation, depression, spike-timing-dependent plasticity, and excitatory postsynaptic currents. This synaptic emulation holds tremendous promise for applications in neuromorphic computing, offering the opportunity to replicate the adaptive learning principles observed in biological synapses. In addition, we evaluate the device's suitability for pattern recognition within a neural network using the modified National Institute of Standards and Technology dataset. Our assessment reveals that the Pt/TaOx/Ta memristor with an oxidized insulator achieves outstanding potential manifested by an accuracy of 93.25% for the identical pulse scheme and an impressive accuracy of 95.42% for the incremental pulse scheme., (© 2023 Author(s). Published under an exclusive license by AIP Publishing.)

Although vertical configurations for high-density storage require challenging process steps, such as etching high aspect ratios and atomic layer deposition (ALD), they are more affordable with a relatively simple lithography process and have been employed in many studies. Herein, the potential of memristors with CMOS-compatible 3D vertical stacked structures of Pt/Ti/HfO x /TiN-NCs/HfO x /TiN is examined for use in neuromorphic systems. The electrical characteristics (including I - V properties, retention, and endurance) were investigated for both planar single cells and vertical resistive random-access memory (VRRAM) cells at each layer, demonstrating their outstanding non-volatile memory capabilities. In addition, various synaptic functions (including potentiation and depression) under different pulse schemes, excitatory postsynaptic current (EPSC), and spike-timing-dependent plasticity (STDP) were investigated. In pattern recognition simulations, an improved recognition rate was achieved by the linearly changing conductance, which was enhanced by the incremental pulse scheme. The achieved results demonstrated the feasibility of employing VRRAM with TiN nanocrystals in neuromorphic systems that resemble the human brain.