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The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has claimed millions of lives worldwide, not to mention innumerable losses in the global economy and disruptions in social relationships. Unfortunately, state-of-the-art treatments still lag behind the fast emergence of new variants of concern. The key to resolve this issue is to develop broad-spectrum antivirals with innovative antiviral mechanisms in which coronaviruses are deactivated regardless of their variant development. Herein, we report a new antiviral strategy involving extracellular disintegration of viral proteins that are indispensable for viral infection with hyperanion-grafted enediyne molecules. The sulfate groups ensure low cellular permeability and rather low cytotoxicity of the molecules, while the core enediyne generates reactive radical species and causes significant damage to the spike (S) protein of coronavirus. The enediyne compounds exhibit antiviral activity at micromolar to nanomolar concentrations, and the selectivity index of up to 20,000 against four kinds of human coronaviruses, including the SARS-CoV-2 omicron variant, suggesting the high potential of this new strategy in combating the COVID-19 pandemic.

With the rapid development of e-commerce in China and the global pandemic of COVID-19, more and more sales personnel and brands have abandoned the physical retail industry and started investing in e-commerce. The consumer culture of livestream e-commerce is becoming popular in China. However, a report from Southern Finance Omnimedia Corp of China pointed out that among China's top 1,000 livestream sellers, the top 20 sellers have contributed to nearly half of the gross merchandise volume (GMV), using three major Chinese streaming platforms: Taobao, Douyin, and Kuaishou. Moreover, a novice in livestream e-commerce knows less about the important impact factors of the realm. Akin to the adage, “well aware is well prepared,” knowing more about the influencing factors of livestream e-commerce more will be the chances to promote the commercial value. A benchmark research is needed to systematically trace out the most important and influencing factors and to make possible the rising of selling with less effort, hence this study. The research intends to sort out the relevant influencing factors that affect consumers’ shopping motivation in livestream e-commerce by reviewing previous related literature. Then, through the Delphi method, eight experts constructed the 14 main influencing factors that affect consumers’ shopping motivation in livestream e-commerce. Through DEMATEL-ANP, we can not only find the key factors but also sort out the causal relationship between the main key factors, forming a preliminary evaluation model of the commercial value of livestream sellers. The importance-performance analysis (IPA) of these impact factors found that “seller popularity” is the most critical factor affecting consumers’ shopping motivation. At the same time, product discounts, product quality, and the attractiveness of the sellers are being included in effects by the “seller popularity.” The investigation followed in this study revealed that characteristics of the livestream seller are one of the most influencing factor achieving a total weight of 0.3020, whereas the streaming platform is the least influencing factor (total weight is 0.1333). The assessment made the study explore the sustainability of livestream e-commerce in China, and the proposed evaluation model can be used for the preliminary business value evaluation of people engaged in livestream sellers and related industries.

Human activity monitoring is a complex endeavor, which mainly depends on pressure or strain sensors.

Piezoresistive pressure sensors based on conductive polyurethane (PU) sponge have attracted much attention due to their facile fabrication, convenient signal collection and good stability, yet it is a challenge to prepare a cost-effective PU composite for pressure sensing with good sensitivity and a wide strain range. Herein, a conductive poly(vinyl alcohol)/sulfuric gel electrolyte@PU (PVA/H2SO4@PU) composite is fabricated by impregnating commercial PU sponge into a PVA/H2SO4 gel electrolyte. The conductivity of the as-prepared composite is provided by the gel electrolyte and the carbonized PU sponge by sulfuric acid. Due to the typical porous structure of the elastic PU sponge and the high elasticity of the PVA/H2SO4 gel electrolyte, the composite shows excellent compression performance. The PVA/H2SO4@PU-based piezoresistive pressure sensor exhibits a good sensitivity of 0.080 kPa−1 in a tiny and low pressure range (0.51–3.01 kPa), a wide sensing range (0–80.0%) and a long durability over 1800 s (1325 cycles). Thereafter, the pressure sensor was used to monitor facial muscle movements, airflow, finger bending, grasping different amounts of weights, etc. This indicates that the pressure sensor obtained in this work has broad application prospects in human activity monitoring. Furthermore, the PVA/H2SO4 gel electrolyte is readily available and inexpensive, which reduces the cost of the composites for pressure sensing.

The development of wearable devices has stimulated significant engineering and technologies of textile electronics (TEs). Improving sensing, energy-storing, and electro-heating capabilities of TEs is still challenging but crucial for their practical applications. Herein, a drip-coating method that constructs a dense β-FeOOH scaffold on a nylon strip for enhancing polypyrrole loading is proposed, which facilitates the fabrication of highly conductive and hydrophobic PFCNS (polypyrrole/β-FeOOH/nylon strip). The space provided by the β-FeOOH scaffold increases the mass of polypyrrole on fibers from 1.1 (polypyrrole/nylon strip) to 3.0 mg cm

This study presented an experimental investigation on heat transfer performance of a shell-and-tube heat exchanger with and without circular fins. Particular attention has been paid to the effect of injection flow rate of heat transfer fluid (HTF) on the thermal performance of the heat exchanger. A purposely-designed apparatus was built for experimental observation. Results showed that the application of fins had a great effect on improving phase change heat transfer and the full charging time was significantly reduced. Injection flow rate of HTF was found to have little influence upon the performance of the heat exchanger.

The flexible piezoresistive sensor (FPS) with typical three-dimensional (3D) structure is a key component for many wearable products because of its excellent performance. We report a high-performance FPS based on micro-nano 3D networked conductive electrospun membrane. This membrane is framed by thermoplastic polyurethane electrospun membrane (TPUEM) coated with reduced graphene oxide(rGO) bridged conductive poly (styrene-co-methacrylic acid)@polypyrrole (P(St-MAA)@PPy) microspheres. Interestingly, P(St-MAA)@PPy microsphere is adsorbed on the surface of rGO/TPU fiber, leading to the formation of a hierarchical conductive surface that enhances the sensitivity to external pressure. The obtained P(St-MAA)@PPy/rGO/TPUEM pressure sensor can effectively detect small pressure (0.94 Pa). The pressure sensor shows a low operating voltage (1.0 V), high sensitivity (13.65 kPa−1), short response time (37 ms), and excellent cycle stability (over 1650 cycles). As a result, this pressure sensor is used to monitor the body's physiological signals and motions, such as the human pulse, facial muscles and joint movements, etc. This novel P(St-MAA)@PPy/rGO/TPUEM pressure sensor can meet the performance requirements of wearable electronic products, demonstrating great potential in human health monitoring and human-computer interaction.