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Fiber reinforced plastics using natural fibers are attracting keen interest as renewable materials and for efficient CO2 fixation. We focused on Erianthus arudinaceus as a cellulose resource crop for enhancing the mechanical properties and the thermal stability of biocomposites and improving the interfacial adhesion between polypropylene (PP) and Erianthus fiber (ETF). To achieve this purpose, we proposed classifications of fiber size after grinding. Maleic anhydride-polypropylene (MAPP) is used as a compatibilizer in the polymer matrix. The ETF/PP and ETF/PP/MAPP composites were prepared using a twin screw extrusion followed by injection molding. Tensile strength and flexuraI strength of ETF/PP composites revealed a weak adhesion between matrix and wood fibers. However, the ETF/PP/MAPP composites show improved tensile strength and flexural strength. Moreover, we examined the influence of ETF fiber size in biocomposites on mechanical strength and thermal degradation stability. [ABSTRACT FROM AUTHOR]

The purpose of this study is to propose a conceptual model for a community of practice, which is the core of knowledge management, by conducting a literature review. Communities of practices can effectively solve business problems or achieve specific objectives by generating and sharing powerful knowledge. The conceptual model suggests successive approaches to develop communities of practice, starting with accomplishing the fundamental dimension of motivating employees, through creating an organizational culture, and culminating in the strategic dimension of providing organizational support. The model also indicates potential barriers when implementing knowledge management interventions, such as cultural issues, internal fear of criticism, external confidentiality issues, lack of time, and shortage of technology. Based on the conceptual model, implications and recommendations for HRD practitioners seeking to optimally implement communities of practice in their organizations are presented. [ABSTRACT FROM AUTHOR]

Photoinverter and electrical-inverter applications of amorphous GaSnZnO thin-film transistors (GTZO-TFTs) with Al2O3 dielectrics were studied. The inverters were composed of two serially connected top-gate GTZO-TFTs with different gate electrodes: semitransparent conducting NiOx and opaque Al. Since the two electrodes have so different work functions as to properly arrange the respective threshold voltages of driver and load TFTs, our inverter exhibited a desirable voltage transfer characteristics with voltage gain of over 25 for electrical gating. A dynamic photogating was demonstrated with an output photogain of ∼2 V as we applied a blue illumination onto semitransparent NiOx gate, through which the photons are transmitted to excite the trapped electrons at the Al2O3 dielectric/GTZO channel interface. [ABSTRACT FROM AUTHOR]

Background/Aims Small rectal neuroendocrine tumors (NETs) can be resected endoscopically. This study aimed to determine whether modified endoscopic mucosal resections (EMRs), including EMR with ligation (EMR-L), EMR with precutting (EMR-P), and strip biopsy, are superior than the conventional EMR (cEMR) in achieving histological complete and curative resections for the treatment of rectal NETs. Methods The medical records of 215 patients who were treated with endoscopic resections for well-differentiated rectal NETs <1.5 cm in size between January 2011 and July 2017 were retrospectively evaluated. Of the patients, 110, 33, 29, and 43 were treated with cEMR, EMR-P, EMR-L, and strip biopsy, respectively. For each method, histological complete resection (negative resection margin) and curative resection rates (negative resection margin with no lymphovascular invasion) were calculated. Results The histological complete resection rates for cEMR, EMR-P, EMR-L, and strip biopsy were 74.5%, 90.9%, 93.1%, and 90.7%, respectively, and the cEMR was significantly inferior to the modified EMRs (p=0.045 for cEMR vs EMR-P, p=0.031 for cEMR vs EMR-L, p=0.027 for cEMR vs strip biopsy, and p=0.001 for cEMR vs modified EMRs). The curative resection rates were 58.2%, 84.8%, 82.8%, and 76.7% for cEMR, EMR-P, EMR-L, and strip biopsy, respectively, and cEMR was significantly inferior to the modified EMRs (p=0.006 for cEMR vs EMR-P, p=0.018 for cEMR vs EMR-L, p=0.041 for cEMR vs strip biopsy, and p=0.000 for cEMR vs. modified EMRs) (Table 1). No significant differences were observed in en bloc resection (p=0.096) and complication rates (p=0.071) but EMR-P required longer procedure time (p=0.000). Conclusions The modified EMR techniques were better than the conventional EMR in accomplishing histological complete and curative resections for the endoscopic treatment of rectal NETs. [ABSTRACT FROM AUTHOR]

Background/Aims Ischemic colitis (IC) is considered to be an intestinal injury as a result of insufficient blood flow and severities of IC can range from mild to life-threatening. The aim of this study was to identify predictive risk factors and propose a scoring model of severe IC. Methods In a retrospective study, we analyzed medical records of patients with IC admitted to Chungnam National University Hospital from January 2010 to December 2018. The patients were divided into two groups by Favier endoscopic classification: non-severe (stage 1) and severe (stage 2, 3). By using the logistic regression analysis, we obtained a new risk scoring model for early prediction of severe IC. Results A total of 274 patients with endoscopic evaluated IC were included. One hundred and eighty-one patients (66.1%) were classified as severe IC. In a multivariate analysis, five factors were independently and significantly associated with severe IC: tachycardia (odds ratio [OR], 3.83; 95% confidence interval [CI], 1.65 to 8.87; p=0.002), low-dose aspirin (OR, 4.45; 95% CI, 2.05 to 9.69; p<0.001), non-aspirin antiplatelet agents (OR, 4.67; 95% CI, 1.68 to 12.95; p=0.003), elevated C-reactive protein (OR, 4.80; 95% CI, 2.57 to 8.97; p<0.001) and thrombocytopenia (OR, 7.86; 95% CI, 2.01 to 30.7; p=0.003). AUROC (area under receiver operating characteristic curve) of our new risk scoring model was 0.796 (95% CI, 0.743 to 0.842; p<0.001) (Fig. 1). Conclusions A new risk scoring model based on presence of tachycardia, administration of low-dose aspirin and non-aspirin antiplatelet agents, elevated C-reactive protein and thrombocytopenia could be used to predict the severity of IC in early stage. [ABSTRACT FROM AUTHOR]

Abstract Background This study aimed to compare the clinical and radiological outcomes of medial patellofemoral ligament reconstruction (MPFLR) between anatomic femoral tunnel positions at anterior and posterior footprints. Methods Fifty-seven patients who underwent MPFLR for patellofemoral instability with anterior or posterior femoral tunnels between 2014 and 2021 with at least 2 years of follow-up were retrospectively analyzed. Based on postoperative images, the femoral tunnel positions anterior to the line connecting the adductor tubercle and medial epicondyle were assigned to the anterior group, group A, and those posterior to the line to the posterior group, group P. Thirty-two patients were included in group A (mean age, 22.4 ± 8.8 years), and another 25 patients were included in group P (mean age, 21.1 ± 6.1 years). The International Knee Documentation Committee (IKDC) subjective score, Lysholm score, Tegner activity score, Kujala score, and complications were evaluated. Radiologically, the Caton–Deschamps index (CDI), patellar tilt angle, and patellofemoral osteoarthritis (PFOA) using the Kellgren–Lawrence (KL) scale were evaluated. The patellofemoral cartilage status according to the International Cartilage Repair Society (ICRS) grade, bone contusion, femoral tunnel enlargement, and MPFL graft signal intensity were also evaluated. Results All clinical scores significantly improved in both groups (p

Background: Although there is no obvious recommendation for the management of pneumothorax recurrence after surgery, chemical pleurodesis with tetracycline has been applied as a significant treatment approach. The objective of this study was to evaluate the effectiveness of chemical pleurodesis with tetracycline for the management of postoperative recurrence of primary spontaneous pneumothorax (PSP). Methods: We retrospectively analyzed patients who underwent video-assisted thoracic surgery (VATS) as therapy for PSP at Hallym University Sacred Heart Hospital from January 2010 to December 2016. Patients who had ipsilateral recurrence after surgery were included in this study. Patients who underwent pleural drainage with chemical pleurodesis were compared with patients who only underwent pleural drainage. Results: In total, 932 patients who underwent VATS for PSP were analyzed, and ipsilateral recurrence after surgery occurred in 67 patients (7.1%). The treatment modalities for recurrence after surgery were observation (n=12), pleural drainage alone (n=16), pleural drainage with chemical pleurodesis (n=34), and repeated VATS (n=5). Eight of the 16 patients (50 %) treated with pleural drainage alone had recurrence again, while 15 of the 34 patients (44.1%) treated with pleural drainage and chemical pleurodesis experienced further recurrence. Chemical pleurodesis with tetracycline did not show a meaningful difference in the re-recurrence rate in comparison with pleural drainage alone (p=0.332). Conclusion: Chemical pleurodesis with tetracycline for the management of postoperative recurrence of PSP was not effective. Further research is required to identify alternative drugs that can significantly decrease the re-recurrence rate.

Abstract Artificial neural networks (ANNs) are widely used in numerous artificial intelligence‐based applications. However, the significant amount of data transferred between computing units and storage has limited the widespread deployment of ANN for the artificial intelligence of things (AIoT) and power‐constrained device applications. Therefore, among various ANN algorithms, quantized neural networks (QNNs) have garnered considerable attention because they require fewer computational resources with minimal energy consumption. Herein, an oxide‐based ternary charge‐trap transistor (CTT) that provides three discrete states and non‐volatile memory characteristics are introduced, which are desirable for QNN computing. By employing a differential pair of ternary CTTs, an artificial synaptic segregation with multilevel quantized values for QNNs is demostrated. The approach establishes a platform that combines the advantages of multiple states and robustness to noise for in‐memory computing to achieve reliable QNN performance in hardware, thereby facilitating the development of energy‐efficient AIoT.

Abstract Background Esophageal squamous cell carcinoma (ESCC) still remains intractable disease with few therapeutic options. Programmed death-ligand 1 (PD-L1), which is essential for immune evasion, is involved in the pathogenesis of ESCC and thus is a potential therapeutic target. PIK3CA, KRAS, and BRAF mutations, microsatellite instability (MSI) caused by deficient mismatch repair (dMMR), and human papillomavirus (HPV) can potentially upregulate PD-L1 expression, which might contribute to the clinical outcome of patients with ESCC. Methods We investigated the significance of the present druggable markers [PD-L1, PIK3CA, KRAS, and BRAF mutations, MSI caused by deficient dMMR, and HPV] in 64 curatively resected ESCCs, using immunohistochemistry (PD-L1 and MMR protein expression), direct sequencing (KRAS, BRAF, and PIK3CA mutations), real-time PCR (HPV infection), and MSI using quasi-monomorphic markers. Results PD-L1 expression, PIK3CA mutation, and MSI/dMMR were detected in 35.9, 12.5, and 17.2% of ESCCs, respectively. HPV was rarely detected (1.6%) (high-risk HPV68), whereas KRAS and BRAF mutations were not detected in ESCCs. PD-L1-positive tumors were not correlated with PIK3CA mutation or MSI/dMMR (all P > 0.05). PD-L1, PIK3CA mutation, and MSI/dMMR characterized the patients associated with light smoking, female and younger age, and younger age and well-differentiated tumors, respectively (all P

Abstract Background Therapeutic extracorporeal membrane oxygenation (ECMO) is a challenging procedure in patients who have experienced severe trauma. Particularly, patients with traumatic lung injury and posttraumatic acute respiratory distress syndrome (ARDS) have a high risk of bleeding during this procedure. This study aimed to determine the safety and feasibility of ECMO in patients with traumatic ARDS. Methods We retrospectively reviewed medical records and investigated the clinical outcomes of ECMO in 42 patients with traumatic ARDS, among whom near-drowning (42.9%) was the most frequent cause of injury. Results Thirty-four of 42 patients (81%) survived and were discharged after a median hospital stay of 23 days. A multivariate analysis identified a lactate level (odds ratio: 1.493, 95% confidence interval: 1.060–2.103, P = 0.022) and veno-venous (VV) ECMO (odds ratio: 0.075, 95% confidence interval: 0.006–0.901, P = 0.041) as favorable independent predictors of survival in patients with traumatic ARDS who underwent ECMO. The optimal cut off value for pre-ECMO lactate level was 10.5 mmol/L (area under the curve = 0.929, P = 0.001). In Kaplan-Meier analysis, the survival rate at hospital discharge was significant higher among the patients with a pre-ECMO lactate level of 10.5 mmol/L or less compared with patients with pre-ECMO lactate level greater than 10.5 mmol/L (93.8% versus 40.0%, respectively; P = 0.01). Conclusions ECMO yielded excellent survival outcomes, particularly in patients with low pre-treatment lactate levels who received VV ECMO. Therefore, ECMO appears safe and highly feasible in a carefully selected population of trauma patients.

A 71-year-old man was referred for an anterior chest wall mass. Chest computed tomography (CT) and positron emission tomography-CT suggested a malignant tumor. Surgical biopsy through a vertical subxiphoid incision revealed an extra-gastrointestinal stromal tumor (EGIST). En bloc resection of the tumor, including partial resection of the sternum, costal cartilage, pericardium, diaphragm, and peritoneum, was performed. Pathologic evaluation revealed a negative resection margin and confirmed the tumor as an EGIST. On postoperative day 17, the patient was discharged without any complications. At the 2-week follow-up, the patient was doing well and was asymptomatic.