EEG-Based Auditory Attention Detection via Frequency and Channel Neural Attention

10.1109/thms.2021.3125283IEEE Transactions on Human-Machine System

The Microstructure and Mechanical Properties of Dual-Spot Laser Welded-Brazed Ti/Al Butt Joints with Different Groove Shapes

Laser welding-brazing was performed to join Ti and Al together. The dual-spot laser beam mode was selected as the heat source in this study. Ti-6Al-4V and 6061-T6 Al alloys were selected as the experimental materials. Al-12Si welding wire was selected as the filler material. The effect of groove shape on the weld appearance, microstructure, temperature field, and mechanical performance of Ti/Al welded-brazed butt joints was investigated. The interfacial intermetallic compound (IMC) layer at the Ti/Weld brazing interface was inhomogeneous in joints with I-shaped and Y-shaped grooves. In Ti/Al joints with V-shaped grooves, the homogeneity of temperature field and IMC layer was improved, and the maximum thickness difference of IMC layer was only 0.20 μm. Nano-sized granular Ti7Al5Si12, Ti5Si3, and Ti(Al,Si)3 constituted the IMCs. The tensile strength of Ti/Al joints with V-shaped grooves was the highest at 187 MPa. The fracture mode transformed from brittle fractures located in the IMC layer to ductile fractures located in the Al base metal, which could be attributed to the improvement of the IMC layer at the brazing interface

A Neural-Inspired Architecture for EEG-Based Auditory Attention Detection

10.1109/THMS.2022.317621

An Overview of Flexible Sensors: Development, Application, and Challenges

The emergence and advancement of flexible electronics have great potential to lead development trends in many fields, such as “smart electronic skin” and wearable electronics. By acting as intermediates to detect a variety of external stimuli or physiological parameters, flexible sensors are regarded as a core component of flexible electronic systems and have been extensively studied. Unlike conventional rigid sensors requiring costly instruments and complicated fabrication processes, flexible sensors can be manufactured by simple procedures with excellent production efficiency, reliable output performance, and superior adaptability to the irregular surface of the surroundings where they are applied. Here, recent studies on flexible sensors for sensing humidity and strain/pressure are outlined, emphasizing their sensory materials, working mechanisms, structures, fabrication methods, and particular applications. Furthermore, a conclusion, including future perspectives and a short overview of the market share in this field, is given for further advancing this field of research

A New Method of Assessing Environmental Flows in Channelized Urban Rivers

Assessing environmental flows (e-flows) for urban rivers is important for water resources planning and river protection. Many e-flow assessment methods have been established based on species’ habitat provision requirements and pollutant dilution requirements. To avoid flood risk, however, many urban rivers have been transformed into straight, trapezoidal-profiled concrete channels, leading to the disappearance of valuable species. With the construction of water pollution-control projects, pollutant inputs into rivers have been effectively controlled in some urban rivers. For these rivers, the e-flows determined by traditional methods will be very small, and will consequently lead to a low priority being given to river protection in future water resources allocation and management. To more effectively assess the e-flows of channelized urban rivers, we propose three e-flow degrees, according to longitudinal hydrological connectivity (high, medium, and low), in addition to the pollutant dilution water requirement determined by the mass-balance equation. In the high connectivity scenario, the intent is for the e-flows to maintain flow velocity, which can ensure the self-purification of rivers and reduce algal blooms; in the medium connectivity scenario, the intent is for the e-flows to permanently maintain the longitudinal hydrological connectivity of rivers that are isolated into several ponds by means of weirs, in order to ensure the exchange of material, energy, and information in rivers; and in the low connectivity scenario, the intent is for the e-flows to intermittently connect isolated ponds every few days (which is designed to further reduce e-flows). The proposed methods have been used in Shiwuli River, China, to demonstrate their effectiveness. The new methods can offer more precise and realistic e-flow results and can effectively direct the construction and management of e-flow supply projects. Keywords: Environmental flow, Urban river, Channelized rivers, River restoratio

Electrochemical alcohol oxidation reaction on Precious‐Metal‐Free catalysts:Mechanism, activity, and selectivity

The electrochemical alcohol oxidation reaction (AOR) is pivotal for the development of sustainable energy. The complete oxidation of alcohols has attracted extensive attention as a vital process in fuel cells. Moreover, as an alternative reaction to the oxygen evolution reaction, the selective oxidation of alcohols emerges as an effective means to lower the energy expenditure associated with electrolytic hydrogen production while yielding high‐value products. Nonprecious metal materials have been widely applied in the selective oxidation catalysis of alcohols due to their cost‐effectiveness and excellent durability. In recent years, leveraging the advantages of nonprecious metal materials in electrocatalytic AOR, researchers have delved into catalytic mechanisms and various efficient catalysts have been fabricated and evaluated. This review provides an overview of the current advancements in the electrocatalytic selective oxidation of diverse alcohols and the catalytic systems centered around nonprecious metal materials. It systematically summarizes the shared traits and distinctions in catalytic reaction characteristics across various systems, thereby laying the theoretical foundation for developing novel catalyst systems that are efficient, stable, and highly selective. This review will facilitate the utilization of nonprecious metal catalysts further toward the electrocatalytic oxidation of alcohols

Mapping global lake dynamics reveals the emerging roles of small lakes

Lakes are important natural resources and carbon gas emitters and are undergoing rapid changes worldwide in response to climate change and human activities. A detailed global characterization of lakes and their long-term dynamics does not exist, which is however crucial for evaluating the associated impacts on water availability and carbon emissions. Here, we map 3.4 million lakes on a global scale, including their explicit maximum extents and probability-weighted area changes over the past four decades. From the beginning period (1984–1999) to the end (2010–2019), the lake area increased across all six continents analyzed, with a net change of +46,278 km2, and 56% of the expansion was attributed to reservoirs. Interestingly, although small lakes (<1 km2) accounted for just 15% of the global lake area, they dominated the variability in total lake size in half of the global inland lake regions. The identified lake area increase over time led to higher lacustrine carbon emissions, mostly attributed to small lakes. Our findings illustrate the emerging roles of small lakes in regulating not only local inland water variability, but also the global trends of surface water extent and carbon emissions

The expression profile and tumorigenic mechanisms of CD97 (ADGRE5) in glioblastoma render it a targetable vulnerability

Glioblastoma (GBM) is the most common and aggressive primary brain malignancy. Adhesion G protein-coupled receptors (aGPCRs) have attracted interest for their potential as treatment targets. Here, we show that CD97 (ADGRE5) is the most promising aGPCR target in GBM, by virtue of its de novo expression compared to healthy brain tissue. CD97 knockdown or knockout significantly reduces the tumor initiation capacity of patient-derived GBM cultures (PDGCs) in vitro and in vivo. We find that CD97 promotes glycolytic metabolism via the mitogen-activated protein kinase (MAPK) pathway, which depends on phosphorylation of its C terminus and recruitment of β-arrestin. We also demonstrate that THY1/CD90 is a likely CD97 ligand in GBM. Lastly, we show that an anti-CD97 antibody-drug conjugate selectively kills tumor cells in vitro. Our studies identify CD97 as a regulator of tumor metabolism, elucidate mechanisms of receptor activation and signaling, and provide strong scientific rationale for developing biologics to target it therapeutically in GBM