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Due to the potential environment and health risks of tert-butylhydroquinone (TBHQ), rapid, portable, selective and sensitive quantification of TBHQ in food and the environment are strictly essential. With this in mind, a selective, sensitive and rapid colorimetric TBHQ biosensor was developed using rationally designed copper-crosslinked carbon dot hydrogel nanozyme (BC-CDs@Cu). The BC-CDs@Cu had a high peroxidase-like activity toward the chromogenic reaction of hydrogen peroxide with dopamine via the generation of hydroxyl radicals and electron transfer process. The Michaelis-Menten constants of BC-CDs@Cu for dopamine and hydrogen peroxide were determined to be 0.86 and 0.91 mM. The added TBHQ markedly inhibited the BC-CDs@Cu-catalyzed dopamine oxidation by hydrogen peroxide, ascribing to the highly effective and rapid scavenging of hydroxyl radicals and the suppression of electron transfer. The inhibitory extent was applied for well quantifying TBHQ in the range of 0.5 − 20.0 μM with a detection limit of 70 nM. The proposed biosensor had a negligible response to various interfering substances. Moreover, a smartphone-assisted visual ratiometric biosensor was fabricated, and used to accomplish portable quantification of TBHQ in edible oils and water samples. This work reveals the enormous potential of hydrogel nanozyme, which will open a new situation for the detection of hazardous substances. [Display omitted] • The BC-CDs@Cu hydrogel nanozyme was rationally designed for colorimetric TBHQ sensing. • The BC-CDs@Cu hydrogel nanozyme was simply synthesized on a large scale. • The peroxidase-like mechanism of BC-CDs@Cu hydrogel nanozyme was revealed. • The inhibition mechanism of BC-CDs@Cu hydrogel nanozyme by TBHQ was revealed. • Smartphone-assisted visual detection of TBHQ in edible oils and water was achieved. [ABSTRACT FROM AUTHOR]

We demonstrate significantly longer plasmon lifetime and stronger electric field enhancement by lifting the nanoantenna arrays above the substrate by dielectric nanopillars. The role of the pillar is to offer a more homogeneous dielectric background allowing stronger diffraction coupling among plasmonic nanoantennas leading to a Fanolike asymmetric lineshape. It is found that the electric fields around the nanoantennas can be greatly enhanced when the Fanolike resonance is excited, and a 4.2 times enhancement is achieved compared with the pure resonance in individual nanoantennas. Furthermore, only a collective surface mode with its electric fields of the same direction as the induced electric moment in the nanoantennas could mediate the excitation of such a Fanolike resonance. More importantly, the sensitivity and the figure of merit (FOM) of this plasmonic structure can reach as high as 900 nm/RIU and 53, respectively. Our study offers a new, simple, and efficient way to design the plasmonic systems with desired electric field enhancement and spectral lineshape for different applications. [ABSTRACT FROM AUTHOR]

A ratiometric electrochemical sensor is developed for fast, simple and accurate determination of BHA using polythionine/multiwalled carbon nanotube composite modified glassy carbon electrode (pThi/MWCNT/GCE). The preparation of pThi/MWCNT/GCE is characterized by various analytical techniques. The pThi/MWCNT composite is demonstrated to possess large specific surface area, good electrical conductivity, and high electrocatalytic ability. Moreover, it is demonstrated that the use of ratiometric signal involving the electro-oxidation of both BHA and pThi improves the accuracy and reliability of the BHA analysis due to the built-in correction function of the inner reference polythionine probe. A linear ratiometric signal can be achieved over the concentration range of 0.5–70.0 μM with the detection limit of 0.21 μM (S / N = 3). The BHA sensor also exhibits high selectivity, high reproducibility, and good stability, and can be used for the analysis of BHA in edible oil samples with satisfactory results. A ratiometric electrochemical sensor is constructed for butylated hydroxyanisole (BHA) detection based on polythionine/multiwalled carbon nanotube composite modified glassy carbon electrode (pThi/MWCNT/GCE) in edible oils. [Display omitted] • A ratiometric electrochemical sensor was constructed to detect BHA in edible oil samples. • The ratiometic sensor improved the accuracy and reliability of BHA analysis. • The pThi/MWCNT composite enhanced the analytical performance for BHA detection. • The reaction mechanism of BHA electro-oxidation at the pThi/MWCNT/GCE was proposed. [ABSTRACT FROM AUTHOR]

Although companies are investing more in avatars to improve interactivity and engage their customers better, the effectiveness of avatars in online markets needs more evidences. This study explores the influence mechanism of anthropomorphism on consumers' willingness to accept virtual live streamers, grounded in social identity theory and construal levels theory. Three research hypotheses were formulated and tested through an online scenario experiment employing a 2 (high anthropomorphism vs. low anthropomorphism) and 2 (utilitarian products vs. hedonic products) between-subjects design (N = 214). The results reveal that anthropomorphism positively influences consumers' willingness to accept virtual live streamers. This effect is mediated through the chain mediation effects of psychological distance and trust (effect = 0.181, 95% confidence interval = [0.075, 0.299]). Additionally, product type serves as a moderator in this process. Specifically, the mediation is significant for utilitarian products (effect = 0.410, 95% confidence interval = [0.203, 0.604]) but not for hedonic products (effect = 0.102, 95% confidence interval = [-0.106, 0.310]). These findings contribute to understanding the effectiveness of avatar marketing in live streaming commerce, specifically consumers' willingness to accept virtual live streamers, and enrich the literature on anthropomorphism in online marketplaces. Furthermore, they assist live streaming commerce operators in developing effective anthropomorphism strategies to enhance the utilization efficiency of virtual live streamers. • Anthropomorphism positively influences consumers' willingness to accept virtual live streamers. • Psychological distance and trust form a chain mediation effect. • Product type plays a crucial moderator, the mediation is significant for utilitarian products but not for hedonic products. • Aid operators in developing anthropomorphism strategies to optimize the efficiency of using virtual live streamers. [ABSTRACT FROM AUTHOR]

An important component of any CO2 sequestration project is seismic monitoring for tracking changes in subsurface physical properties, such as velocity and density. Different reservoirs have different amplitude variation with offset (AVO) responses, which can define underground conditions. In the present paper we investigate walkaway vertical seismic profile (VSP) AVO response to CO2 injection at the Ketzin site, the first European onshore CO2 sequestration pilot study dealing with research on geological storage of CO2. First, we performed rock physics analysis to evaluate the effect of injected CO2 on seismic velocity using the Biot-Gassmann equation. On the basis of this model, the seismic response for different CO2 injection saturation was studied using ray tracing modeling. We then created synthetic walkaway VSP data, which we then processed. In contrast, synthetic seismic traces were created from borehole data. Finally, we found that the amplitude of CO2 injected sand layer with different gas saturations were increased with the offset when compared with the original brine target layer. This is the typical class III AVO anomaly for gas sand layer. The AVO responses matched the synthetic seismic traces very well. Therefore, walkaway VSP AVO response can monitor CO2 distribution in the Ketzin area. [ABSTRACT FROM AUTHOR]

Salvia bowleyana is a traditional Chinese medicinal plant that is a source of nutritional supplements rich in salvianolic acid B and a potential experimental system for the exploration of salvianolic acid B biosynthesis in the Labiatae. Here, we report a high‐quality chromosome‐scale genome assembly of S. bowleyana covering 462.44 Mb, with a scaffold N50 value of 57.96 Mb and 44,044 annotated protein‐coding genes. Evolutionary analysis revealed an estimated divergence time between S. bowleyana and its close relative S. miltiorrhiza of ~3.94 million years. We also observed evidence of a whole‐genome duplication in the S. bowleyana genome. Transcriptome analysis showed that SbPAL1 (PHENYLALANINE AMMONIA‐LYASE1) is highly expressed in roots relative to stem and leaves, paralleling the location of salvianolic acid B accumulation. The laccase gene family in S. bowleyana outnumbered their counterparts in both S. miltiorrhiza and Arabidopsis thaliana, suggesting that the gene family has undergone expansion in S. bowleyana. Several laccase genes were also highly expressed in roots, where their encoded proteins may catalyze the oxidative reaction from rosmarinic acid to salvianolic acid B. These findings provide an invaluable genomic resource for understanding salvianolic acid B biosynthesis and its regulation, and will be useful for exploring the evolution of the Labiatae. [ABSTRACT FROM AUTHOR]

The basic structure and work mechanism of laser-triggered vacuum switch (LTVS) are introduced briefly in this paper, and the processes of primary plasma production and expansion are analyzed as well. A series of experiments has been carried out with different gap voltages, laser wavelengths, laser energies, polarity configuration modes, switch structures, focal lengths, and laser waveforms. The switch structure is modified to improve the heavy-current capability of the switch, and the gap distance is increased to improve the voltage capacity. The special design of the trigger structure can reduce the dependence on the laser energy of the switch and the time delay. A new laser waveform of LTVS multiple wave crests could further decrease the laser energy, and it is the research basis of laser trigger miniaturization and its application in the LTVS. [ABSTRACT FROM PUBLISHER]

In this paper, the basic structure and working mechanism of laser triggered vacuum switch (LTVS) are briefly introduced, the processes of primary plasma production and expansion are also analyzed. A series of experiments have been carried out under different conditions of LTVS, such as laser energy levels, voltages, and polarity configuration modes. The relationship of conduction and jitter time delays among the laser energy, voltage, and polarity are described, and the effect of main electrode and the expansion of primary plasma are analyzed. The theoretical basis for structure optimization design of LTVS is provided. Under positive polarity configuration that is beneficial to generate the cathode spots, the high working reliability and small time delay of LTVS are verified by the experiments. The results prove that the expansion of primary plasma is the growth of plasma sheath near cathode. [ABSTRACT FROM PUBLISHER]