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This study investigates the effects of a carbon fiber layer formed on the surface of an etched aluminum current collector on the electrochemical properties of the activated carbon electrodes for an electric double layer capacitor. A particle size analyzer, field-emission SEM, and nitrogen adsorption/desorption isotherm analyzer are employed to analyze the structure of the carbon fiber layer. The electric and electrochemical properties of the activated carbon electrodes using a carbon fiber layer are evaluated using an electrode resistance meter and a charge-discharge tester, respectively. To uniformly coat the surface with carbon fiber, we applied a planetary mill process, adjusted the particle size, and prepared the carbon paste by dispersing in a binder. Subsequently, the carbon paste was coated on the surface of the etched aluminum current collector to form the carbon under layer, after which an activated carbon slurry was coated to form the electrodes. Based on the results, the interface resistance of the EDLC cell made of the current collector with the carbon fiber layer was reduced compared to the cell using the pristine current collector. The interfacial resistance decreased from 0.0143 Ω·cm2 to a maximum of 0.0077 Ω·cm2. And degradation reactions of the activated carbon electrodes are suppressed in the 3.3 V floating test. We infer that it is because the improved electric network of the carbon fiber layer coated on the current collector surface enhanced the electron collection and interfacial diffusion while protecting the surface of the cathode etched aluminum; thereby suppressing the formation of Al-F compounds.

A transient model of frost growth on a flat plate was developed, taking the surface characteristics of the plate into consideration. Five regression models were applied, three traditional (Multiple Linear, LASSO, Ridge) and two machine-learning (Artificial Neural Network, Support Vector Machine) regression models. The training database was established using data extracted from previously published experimental studies. The experimental data consisted of forced convection (1067 data points) and natural convection data (992 data points). The model outputs were then evaluated using common statistical indicators and the best performing model was selected. The highest R2 values for the artificial neural network were 0.9899 and 0.9944 for forced and natural convection, respectively, after removal of outliers. The frost thickness was predicted for various conditions, including different surface characteristics. The model produced good predictions despite the occurrence of nonlinear complex growth mechanism dependent on various conditions in the dataset obtained.

This paper presents a high-gain wideband circularly polarized antenna composed of an end-fire dipole array antenna integrated with a metasurface. The antenna consists of a two-layer cascaded non-uniform metasurface made up of 4 × 4 circular patches with cross-slots of unequal lengths placed above an end-fire dipole array antenna with an air gap between the structures. The end-fire dipole array antenna comprises four equally spaced dipole elements, and each dipole is connected to a parallel stripline printed on the front and back sides of the substrate. The metasurface, which is made up of a circular patch with 2 × 2 center patches that have a different radius than the outer patches, and the cross-slots of unequal lengths are used for the polarization conversion of a linearly polarized wave to a circularly polarized wave. The measured reflection coefficients for |S11| < -10 dB yielded an impedance bandwidth of 25.6–31.8 GHz (21.5%), a 3-dB axial ratio (AR) bandwidth of 26.1–30.5 GHz (15.5%), a 3-dB gain bandwidth of 26.0–31.1 GHz (17.4%) with a peak gain of 11.0 dBic, and a radiation efficiency of more than 80% in the axial ratio bandwidth.

To assess the diagnostic performances of prostate specific antigen (PSA) and PSA with prostate magnetic resonance imaging (MRI) to predict prostate cancer in patients with PSA ≤ 20 ng/mL.Patients suspected of prostate cancer with a PSA test and prebiopsy MRI were included (n = 881). Prostate biopsy results or follow-up clinical data for 2 years were used to determine the presence of prostate cancer. The diagnostic performance of PSA, MRI, and PSA with MRI (referred to as the protocol) was evaluated. The positive predictive value (PPV) and negative predictive value (NPV) of the MRI were calculated in subgroups of patients with specific ranges of PSA level.Prostate cancer and CSC were diagnosed in 220 and 162 patients, respectively. Adding MRI to PSA could greatly improve specificity and PPV (0.833 and 0.567) for detecting CSC, compared to PSA ≥ 4 ng/mL alone (0.248 and 0.0219). Even though the sensitivity of the protocol (0.679) was lower than PSA (0.938), the NPV of the protocol was comparable to PSA (0.929 vs. 0.924). The protocol consistently showed the superior PPV and NVP to PSA only in not only patients within the gray zone of PSA, but also in patients with higher PSA.In conclusion, this longitudinal observational study confirmed that adding prebiopsy MRI to PSA was consistently beneficial in patients with PSA ≤ 20 ng/mL for avoiding unnecessary biopsy despite decrease in the sensitivity.

Background/Aims: The optimal treatment for acute malignant obstruction of the proximal colon (MOPC, proximal to the splenic flexure) remains challenging. Emergency resection, the traditional modality for MOPC, has shown significantly high mortality and morbidity rates, according to recent studies. This study aimed to investigate the clinical outcomes of stent vs stoma as a bridge to curative surgery for MOPC.Methods: This retrospective cohort study included 72 patients who underwent endoscopic placement of a self-expanding metallic stent (SEMS) or loop ileostomy for MOPC at six referral centers between January 2011 and July 2021. Clinical and pathological characteristics, procedure-related complications, and long-term mortality rates after curative surgery were analyzed.Results: During a mean follow-up period of 32 months, 30 patients (41.7%) underwent ileostomy preferentially for more proximal cancer, complete obstruction, and advanced tumor stage compared to the SEMS group. No difference was found in procedure-related complications, but five deaths were observed after ileostomy. Survival analysis for 5-year mortality after curative surgery showed no significant difference between the bridge modalities (log-rank p = 0.253).Conclusions: In this study, SEMS as a bridge to surgery showed relatively safe results in terms of post-procedural mortality. However, these results should be considered when performing ileostomy in patients with more advanced malignant obstruction.

Objectives. Otitis media is a common infection worldwide. Owing to the limited number of ear specialists and rapid development of telemedicine, several trials have been conducted to develop novel diagnostic strategies to improve the diagnostic accuracy and screening of patients with otologic diseases based on abnormal otoscopic findings. Although these strategies have demonstrated high diagnostic accuracy for the tympanic membrane (TM), the insufficient explainability of these techniques limits their deployment in clinical practice.Methods. We used a deep convolutional neural network (CNN) model based on the segmentation of a normal TM into five substructures (malleus, umbo, cone of light, pars flaccida, and annulus) to identify abnormalities in otoscopic ear images. The mask R-CNN algorithm learned the labeled images. Subsequently, we evaluated the diagnostic performance of combinations of the five substructures using a three-layer fully connected neural network to determine whether ear disease was present.Results. We obtained the receiver operating characteristic (ROC) curve of the optimal conditions for the presence or absence of eardrum diseases according to each substructure separately or combinations of substructures. The highest area under the curve (0.911) was found for a combination of the malleus, cone of light, and umbo, compared with the corresponding areas under the curve of 0.737–0.873 for each substructure. Thus, an algorithm using these five important normal anatomical structures could prove to be explainable and effective in screening abnormal TMs.Conclusion. This automated algorithm can improve diagnostic accuracy by discriminating between normal and abnormal TMs and can facilitate appropriate and timely referral consultations to improve patients’ quality of life in the context of primary care.

Background This study investigated the predictive potential of the albumin-to-alkaline phosphatase ratio (AAPR) for cerebrovascular accident (CVA) occurrence in patients with antineutrophil cytoplasmic antibody–associated vasculitis. Methods This study included 239 AAV patients and reviewed their medical records retrospectively. AAPR was calculated using the following formula: AAPR = serum albumin (g/dL)/serum alkaline phosphatase (IU/L). CVA was defined only as cerebral infarction after AAV diagnosis in this study. In patients with CVA and those without CVA, the follow-up duration based on CVA was defined as the period from AAV diagnosis to CVA occurrence and to the last visit day, respectively. Results The median age of 239 AAV patients (130 microscopic polyangiitis, 64 granulomatosis with polyangiitis, and 45 eosinophilic granulomatosis with polyangiitis) was 59.0 years and 32.6% were men. The median serum albumin and alkaline phosphatase levels, and AAPR were 3.7 g/dL, 70.5 IU/L and 0.051, respectively. Nineteen patients had CVA during the median follow-up duration of 34.8 months. Using the receiver operator characteristic curve analysis, the optimal cut-off of AAPR for CVA occurrence was obtained as ≤ 0.035. AAV patients with AAPR ≤ 0.035 showed a significantly higher risk of CVA occurrence after AAV diagnosis than those with AAPR >0.035 (relative risk 5.000, p < 0.001). In the multivariable Cox analysis, only AAPR ≤ 0.035 was independently associated with CVA occurrence among AAV patients (hazard ratio 3.195, 95% confidence interval 1.014, 10.062). Conclusion This study demonstrated the predictive potential of AAPR calculated at AAV diagnosis for CVA occurrence after AAV diagnosis among AAV patients.

Lamination of a thin film encapsulation (TFE) layer is regarded as one of the most promising methods that enable the reliable operation of organic electronic devices by attaching the TFE layers thereon directly using an adhesive layer. In this study, a low-temperature curable adhesive thin film with low glass transition temperature (T g) is newly designed and synthesized. Low T g allows conformal contact at the interface of the adhesive layer and the substrate subsequently leads to the enhancement of adhesion, and thus the barrier performance of the lamination of barrier film increases. In order to fabricate a low-T g adhesive layer, glycidyl methacrylate (GMA) was copolymerized with a 2-hydroxyethyl acrylate (HEA) monomer in the vapor phase via initiated chemical vapor deposition. With a 5 µm thick p(GMA-co-HEA) adhesive layer, a strong adhesion was readily achieved by curing it at 60 °C for 1 h, with the peel strength of 16.6 N/25 mm, and the water vapor transmission rate of the glass-laminated encapsulation was as low as 3.4 × 10−3 g/m2 · day under accelerating conditions (38 °C, 90% relative humidity). We believe the low-temperature curable thin adhesive layer will serve as a powerful material for the lamination of organic electronic devices in a damage-free way.