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Background: Postoperative atrial fibrillation (A-fib) is a serious complication of cardiac surgery that is associated with increased mortality and morbidity. Traditional 24-hour Holter monitors have limitations, which have prompted the development of innovative wearable electrocardiogram (ECG) monitoring devices. This study assessed a patch-type wearable ECG device (MobiCARE-MC100) for monitoring A-fib in patients undergoing cardiac surgery and compared it with 24-hour Holter ECG monitoring. Methods: This was a single-center, prospective, investigator-initiated cohort study that included 39 patients who underwent cardiac surgery between July 2021 and June 2022. Patients underwent simultaneous monitoring with both conventional Holter and patchtype ECG devices for 24 hours. The Holter device was then removed, and patch-type monitoring continued for an additional 48 hours, to determine whether extended monitoring provided benefits in the detection of A-fib. Results: This 72-hour ECG monitoring study included 39 patients, with an average age of 62.2 years, comprising 29 men (74.4%) and 10 women (25.6%). In the initial 24 hours, both monitoring techniques identified the same number of paroxysmal A-fib in 7 out of 39 patients. After 24 hours of monitoring, during the additional 48-hour assessment using the patch-type ECG device, an increase in A-fib burden (9%→38%) was observed in 1 patient. Most patients reported no significant discomfort while using the MobiCARE device. Conclusion: In patients who underwent cardiac surgery, the mobiCARE device demonstrated diagnostic accuracy comparable to that of the conventional Holter monitoring system.

Abstract Background Acute aortic regurgitation (AR) is uncommon condition and usually results in an emergent situation because the left ventricle does not adapt quickly due to a sudden increase in end-diastolic volume caused by the regurgitant flow. Thoracic endovascular aortic repair (TEVAR) is a procedure that places a stent-graft on the lesion of thoracic aorta through a minimally invasive approach. Case presentation Here we report that a catheter-induced aortic valve injury associated with TEVAR can cause delayed AR, exemplified by the case of a patient who developed acute AR 42 months after TEVAR. For this, aortic valve replacement was performed and the patient was discharged without complications. Conclusion Our results demonstrate that when a catheter-related procedure is performed around the aortic valve, slight injury of the valve can cause aortic insufficiency even 3 years after surgery. Consequently, when performing a catheter-related procedure around the aortic valve, special attention is always required.

Electric vehicles (EVs) offer benefits in terms of reducing emissions and saving energy over other conventional vehicles. There have been various studies on EVs for energy efficiency and driving performance improvement. As an area of EV systems, dual-motor systems with planetary gear trains have been studied for fuel efficiency improvement, but they have limitations for torque vectoring and maximum torque compared to other typical systems. To overcome these limitations, a novel dual-motor EV system with a planetary gear train has been suggested for eco and dynamic driving modes. The system achieves variable motor operating points for energy efficiency improvement by using dual motors with a planetary gear train. Multiple driving modes are implemented by a synchronizer for torque vectoring and motor maximum torque driving. The suggested system was analyzed by comparison with a typical left-and-right-wheel independent drive dual-motor system with representative EPA test cycles. The novel dual-motor system shows not only the possibility of eco driving by improving fuel efficiency compared to typical dual-motor systems but also performance driving with torque vectoring functionality, which is not available for previous dual-motor systems with planetary gear trains.

Background: Patients with high-risk (HR) operable non-small cell lung cancer (NSCLC) may have unique prognostic factors. This study aimed to evaluate surgical outcomes in HR patients and to investigate prognostic factors in HR patients versus standard-risk (SR) patients. Methods: In total, 471 consecutive patients who underwent curative lung resection for NSCLC between January 2012 and December 2017 were identified and reviewed retrospectively. Patients were classified into HR (n=77) and SR (n=394) groups according to the American College of Surgeons Oncology Group criteria (Z4099 trial). Postoperative complications were defined as those of grade 2 or higher by the Clavien-Dindo classification. Results: The HR group comprised more men and older patients, had poorer lung function, and had more comorbidities than the SR group. The patients in the HR group also experienced more postoperative complications (p≤0.001). More HR patients died without disease recurrence. The postoperative complication rate was the only significant prognostic factor in multivariable Cox regression analysis for HR patients but not SR patients. HR patients without postoperative complications had a survival rate similar to that of SR patients. Conclusion: The overall postoperative survival of HR patients with NSCLC was more strongly affected by postoperative complications than by any other prognostic factor. Care should be taken to minimize postoperative complications, especially in HR patients.

Hybrid powertrains have widely been developed as eco-friendly system and commercialized in the passenger vehicle market with clear benefits over conventional powertrains. Accordingly, there have been various research topics on architectures of hybrid power systems to further improve the system performance ability and sizing optimization for the packaging and production cost reduction. In this study, a novel multimode power split hybrid architecture has been suggested, which is based on multiple driving modes such as input- and output-power split and parallel hybrid modes in order to achieve fuel efficiency improvement and sizing optimization. The performance ability and sizing aspects of the invented system have been analyzed in comparison with Toyota Hybrid System (THS), which is a kind of typical power split hybrid architecture. The fuel efficiency of the suggested system has been compared by a backward-facing simulation with Dynamic Programming (DP) for representative driving test cycles from Environmental Protection Agency (EPA). In terms of the component sizing, the maximum torque and speed variation trends of motors have been analyzed according to the velocity variation. In the simulation and analysis results, the invented system shows opportunities to improve fuel efficiency with multiple driving modes and to reduce component sizing of power electronics which is related to the production cost reduction as well as the vehicle packaging space minimization.

A 65-year-old man underwent right trisectionectomy of the liver and reconstruction of the chest wall and diaphragm with a 2-mm Gore-Tex membrane due to recurrent hepatocellular carcinoma. After 3 years, the Gore-Tex membrane in the diaphragm migrated to the abdominal cavity and perforated the colon. We report a rare complication of a Gore-Tex membrane after diaphragm repair.

In recent years, social media messaging app data has served as a precious resource to extract useful information, such as critical clues and evidence in legal trials and criminal investigations. Although these data can be of various types, they are mostly in the form of natural language text. Therefore, to extract information from them efficiently, it is essential to research practical natural language processing approaches. This study proposes applying a deep-learning-based named-entity recognition (NER) system as a natural language processing approach for information extraction to these messaging data. In addition, a system for automatically constructing NER training data is presented using the distant supervision method for the training data of deep-learning models. Because social media messaging app data generally include a significant amount of noise, such as typographical and word-spacing errors, a NER system with robustness against these types of noisy data is required to extract information from the messaging data effectively. The results demonstrate that the proposed approach outperforms that of a NER system with manually labeled training data.

In this work, we fabricated a Pt/SiN/TaN memristor device and characterized its resistive switching by controlling the compliance current and switching polarity. The chemical and material properties of SiN and TaN were investigated by X-ray photoelectron spectroscopy. Compared with the case of a high compliance current (5 mA), the resistive switching was more gradual in the set and reset processes when a low compliance current (1 mA) was applied by DC sweep and pulse train. In particular, low-power resistive switching was demonstrated in the first reset process, and was achieved by employing the negative differential resistance effect. Furthermore, conductance quantization was observed in the reset process upon decreasing the DC sweep speed. These results have the potential for multilevel cell (MLC) operation. Additionally, the conduction mechanism of the memristor device was investigated by I-V fitting.

Junction networks made of longitudinally connected metal oxide nanowires (MOx NWs) have been widely utilized in resistive-type gas sensors because the potential barrier at the NW junctions leads to improved gas sensing performances. However, conventional MOx–NW-based gas sensors exhibit limited gas access to the sensing sites and reduced utilization of the entire NW surfaces because the NW networks are grown on the substrate. This study presents a novel gas sensor platform facilitating the formation of ZnO NW junction networks in a suspended architecture by growing ZnO NWs radially on a suspended carbon mesh backbone consisting of sub-micrometer-sized wires. NW networks were densely formed in the lateral and longitudinal directions of the ZnO NWs, forming additional longitudinally connected junctions in the voids of the carbon mesh. Therefore, target gases could efficiently access the sensing sites, including the junctions and the entire surface of the ZnO NWs. Thus, the present sensor, based on a suspended network of longitudinally connected NW junctions, exhibited enhanced gas response, sensitivity, and lower limit of detection compared to sensors consisting of only laterally connected NWs. In addition, complete sensor structures consisting of a suspended carbon mesh backbone and ZnO NWs could be prepared using only batch fabrication processes such as carbon microelectromechanical systems and hydrothermal synthesis, allowing cost-effective sensor fabrication.

In recent years, research concerning autonomous driving has gained momentum to enhance road safety and traffic efficiency. Relevant concepts are being applied to the fields of perception, planning, and control of automated vehicles to leverage the advantages offered by the vehicle-to-everything (V2X) communication technology. This paper presents a V2X communication-aided autonomous driving system for vehicles. It is comprised of three subsystems: beyond line-of-sight (BLOS) perception, extended planning, and control. Specifically, the BLOS perception subsystem facilitates unlimited LOS environmental perception through data fusion between local perception using on-board sensors and communication perception via V2X. In the extended planning subsystem, various algorithms are presented regarding the route, velocity, and behavior planning to reflect real-time traffic information obtained utilizing V2X communication. To verify the results, the proposed system was integrated into a full-scale vehicle that participated in the 2019 Hyundai Autonomous Vehicle Competition held in K-city with the V2X infrastructure. Using the proposed system, the authors demonstrated successful completion of all assigned real-life-based missions, including emergency braking caused by a jaywalker, detouring around a construction site ahead, complying with traffic signals, collision avoidance, and yielding the ego-lane for an emergency vehicle. The findings of this study demonstrated the possibility of several potential applications of V2X communication with regard to autonomous driving systems.

An optimal design process of a 600 kJ SMES magnet combined with mechanical stress analysis is described. The results have led to the development of an optimum design of a single-pole double pancake coil (DPC) type 600 kJ SMES magnet.

A single phase 5 MVA high temperature superconducting (HTS) transformer is proposed by using 2G wires and AC losses due to the winding methods are analyzed. Its size is shown to be almost similar to that of a 33 MVA single phase HTS transformer.

The study was conducted to determine the stability of daidzein and genistein in model systems with riboflavin, cholorophyll b or methylene blue photosensitization. Results proved that daidzein and genistein were unstable in riboflavin photosensitization.

AC loss is one of the major topics in large AC power applications using high temperature superconductor such as power transformers, transmission cables and fault current limiters because it is closely related to operation efficiency. Multi-stacked tape conductors should be used to transport the large current in those power applications. A research of various arrangements of HTS tapes for multi-stacked tapes has been performed to increase the capacity of transport current in HTS power applications. In this paper, we studied magnetization loss and shield effect from several different arrangements of BSCCO tapes such as Face-to-Face type, regular matrix type (m × 2) and irregular matrix type. The results show that the magnetization loss of the Face-to-Face arrangement was lower than those of the other matrix types for the same stacking numbers. We think that the result was due to the shield effect by demagnetization of adjacent HTS tapes which were located as face to face. [ABSTRACT FROM AUTHOR]

Examines the fabrication and testing of a high temperature superconducting transformer with double pan cake windings. Components of the transformer; Short circuit testing; Full load testing; Over-load capability and reliability of the transformer.

Reports on the results of transport current loss in bifilar winding solenoid type high temperature superconducting (HTS) coil. Transport current loss in solenoid type winding coil with BSCCO tapes; Removal of external field effect generated by transport currents flowing in other tapes in the coil.

A trend in 3D mesh compression is codec design with low computational complexity which preserves the input vertex and face order. However, this added information increases the complexity. We present a fast 3D mesh compression method that compresses the redundant shared vertex information between neighboring faces using simple first-order differential coding followed by fast entropy coding with a fixed length prefix. Our algorithm is feasible for low complexity designs and maintains the order, which is now part of the MPEG-4 scalable complexity 3D mesh compression standard. The proposed algorithm is 30 times faster than MPEG-4 3D mesh coding extension. [ABSTRACT FROM AUTHOR]