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Blockchain is a new distributed infrastructure and computing paradigm, which has been widely used in various fields. For example, utilizing a chain data structure to verify and restore data, using a distributed node consensus algorithm to generate and update data, applying cryptography to ensure safe data transmission, and employing intelligent contracts composed of automated script code to manipulate data. Data, seen as an essential production factor, promotes the rapid development of blockchain. However, opportunities and challenges coexist, and data security on the blockchain is one of the key points that need attention. This paper introduces data security and the technical framework for deblocking, focusing on the techniques of zero knowledge proof, K-Anonymity, secure multi-party computing, ring signature, homomorphic encryption, trusted execution environment, and the association of these data security protection technologies with blockchain, and compares several data security protection technologies. In this survey, the focus of blockchain data security is structured by first mentioning the source of the data, then combining the characteristics of integration and non-tampering to the blockchain to solve the problems of traditional data security, and lastly, using data security technology to solve the blockchain data security on the Internet to achieve the ecological security of the blockchain. • Review the development of blockchain and existing data security technologies. • Expound on the current data security situation and the development of blockchain. • Detailed combining the development and status of data security technologies. • Prospect the future development of blockchain and data security. [ABSTRACT FROM AUTHOR]

This paper introduces an ultra-wideband terahertz thermal absorber, composed of double-layer square groove doped silicon cubes, exhibiting polarization independence. Within the frequency range of 0.9–9.7 THz, the absorption efficiency exceeds 95 %, and within an incident angle range of 0–67°, the absorption rate still maintains above 90 % in the frequency range of 1.4–9.7 THz. Through finite element method (FEM), this study clearly demonstrates the distribution of electromagnetic energy within the thermal absorber and thoroughly elucidates its notable absorption efficiency via impedance matching theory. Compared to existing technologies, the proposed double-layer square groove thermal absorber shows superior performance in terms of absorption efficiency and bandwidth. This ultra-broadband terahertz thermal absorber is highly applicable in areas including biomedical imaging, thermal imaging, and wireless communication. Considering its excellent manufacturing tolerance, this thermal absorber is significant for application in real industrial production. [ABSTRACT FROM AUTHOR]

There are very rich publications devoted to group sequential design, adaptive design and trial monitoring for continuous, binary and time to event endpoints. Many authors also discuss fixed design, blinded sample size re-estimation design and group sequential design for studies with a negative binomial outcome. Nonetheless, literature is sparse in adaptive design for a trial with a negative binomial endpoint. The features of such an endpoint in a flexible trial design setting remains inadequately understood. In this research, we seek to bridge this knowledge gap by offering a thorough examination of utilizing data components from a two-stage adaptive design for unblinded conditional power calculation and corresponding sample size re-estimation. We also provide expression for calculating the probability of meeting the futility criterion to determine the appropriate timing for the interim analysis. To evaluate the performance of the design, we conduct simulations to assess its operation characteristics. Finally, we provide a helpful and illustrative example to demonstrate the practical applications of the methods. [ABSTRACT FROM AUTHOR]

Abstract Conventional arc-melting and casting is the most widely used synthesis method of high-entropy alloys (HEAs). However, the extremely high melting temperature and repetitious melting processes cause the evaporation of some constituent elements with a low melting temperature, resulting in inaccurateness of composition. In this work, in-situ high throughput synthesis of FeCoNiCrCuAl x was carried out in the transmission electron microscope. The dynamic melting process of FeCoNiCrCu with Al was recorded, and the composition of FeCoNiCrCuAl x was examined by an energy dispersive spectrometer. The in-situ high throughput method provides a novel way to prepare HEA samples efficiently. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Molecular dynamics (MD) simulations provided insights into the favorable interactions between xylose nucleosides bearing a phosphonate moiety at their 3′-position and specific residues at the active site of the archetypal RNA-dependent RNA-polymerase (RdRp) of Enterovirus 71. Therefore, a series of xylosyl nucleoside phosphonates with adenine, uracil, cytosine, guanosine, and hypoxanthine as nucleobases were synthesized through multistep sequences starting from a single common precursor. Following antiviral activity evaluation, the adenine containing analogue was found to possess good antiviral activity against RNA viruses displaying an EC 50 of 12 and 16 μM against measles virus (MeV) and enterovirus-68 (EV-68), respectively, whereas lacking cytotoxicity. [Display omitted] • Molecular dynamics (MD) simulations were performed. • The synthesis of five xylosyl nucleoside phosphonates was carried out. • The adenine analogue displayed good activity against measles and enterovius-68. • The synthesized xylosyl nucleoside phosphonates lacked cytotoxicity. [ABSTRACT FROM AUTHOR]

In order to reduce wind-caused disasters and reduce the cost of production in summer, the large-span M-shaped greenhouse with superior wind resistance and cooling performance is proposed. This paper carries out a research on the optimization with the V-angle of M-shaped greenhouse, and the wind effect and ventilation performance of the optimized M-shaped greenhouse and ordinary large-span arch greenhouse (ordinary arch greenhouse) are studied and comparatively analyzed. It is obtained that the wind resistance of M-shaped greenhouse is optimal at a V-angle of 95°. For the four cases of relatively large net wind pressure coefficients of opening windward side vent, leeward side vent, side vents and top vents, the maximum net wind pressure coefficients of M-shaped greenhouse are lower than those of ordinary arch greenhouse. M-shaped greenhouse has higher ventilation efficiency and slightly lower temperature than ordinary arch greenhouse. It can be seen that M-shaped greenhouse has excellent wind resistance in both closed and open states, and has good ventilation and cooling effect in summer. It can be widely used in agricultural production as new wind-resistant cooling plastic greenhouses. • Large-span M-shaped greenhouse that is suitable for mechanization is proposed. • The angle of the V-shaped roof of M-shaped greenhouse is optimized. • M-shaped greenhouse has superior wind resistance and ventilation performance. [ABSTRACT FROM AUTHOR]

This study aimed to prepare the emulsion co-stabilized via soy protein isolate (SPI) and κ-carrageenan (KC) and then investigate the effects of the SPI/KC emulsion on the gel performance of surimi gels. Particle size and optical microscopy findings revealed that the d 4,3 of emulsion droplets reached the minimum (11.800 ± 0.010 μm) at the appropriate SPI/KC ratio (95:5, w/w). The hardness, springiness, gel strength, whiteness, and water holding capacity of surimi gels were maximum (115.38 ± 2.33 N, 6.00 ± 0.14 mm, 8.59 ± 0.20 N, 74.80 ± 0.09, 91.96 ± 0.73%, respectively) when the SPI/KC emulsion was added. According to rheological tests, surimi gels with emulsions possessed higher viscoelastic modulus (G′ and G″). The addition of the SPI/KC emulsion reduced the creep rate (0.011 ± 0.002 s−1) and increased the recovery percentage (45.226 ± 0.497%) of surimi gels compared to the control gel with soybean oil (0.018 ± 0.003 s−1 and 42.026 ± 0.814%), indicating an increased rigidity and elasticity. In addition, the SPI/KC emulsion addition allowed small oil droplets in surimi gels to be uniformly distributed in a dense and ordered protein network. In conclusion, the SPI/KC emulsion optimized the gel characteristics of surimi gels, thereby providing a new idea for developing novel emulsified surimi products. [Display omitted] • SPI/KC emulsion with tiny droplets was obtained at a 95:5 SPI/KC ratio. • SPI/KC emulsion increased the whiteness of surimi gels. • SPI/KC emulsion optimized the textural and rheological properties of surimi gels. • Tiny, evenly distributed oil droplets promoted the creation of dense gel networks. [ABSTRACT FROM AUTHOR]

Deep learning (DL)-based radiofrequency (RF) fingerprinting identification has shown significantly growing importance in the wireless industry including 5G, IoT and Wireless Sensor Networks (WSN). However, there is little investigation on the robustness of the corresponding DL models against adversarial attacks and adversarial defense. This paper discusses the effects of four cutting-edge adversarial attacks on DL-based RF fingerprinting identification and provides a graphical analysis of RF feature perturbations following adversarial attacks. For the first time we also demonstrate the results of combined physical attack (i.e. tuning the drain currents of the power amplifiers) by tuning the physical features of the device hardware (i.e. drain current), and adversarial attacks on DL-based classifiers. Experimental results from 16 Gallium nitride (GaN) power amplifiers (PA) reveal that adversarial attacks can seriously deteriorate the accuracy of RF identification from about 100.00% to below 10.00% even with only 0.50% adversarial perturbation. In order to deal with the problem of decreased accuracy caused by attacks, we proposed an adversarial defense method based on feature-level interpretability (FIAT), which improved the accuracy of RF identification with interpretability analysis. The results compared with several common defense methods validate that the proposed FIAT can maintain an accuracy of 96.00% even when the adversarial attack perturbation is 5.00% and with physical attack. Moreover, the changes of data features in the process of adversarial attacks and defense are given, providing a new way for the interpretability of adversarial attacks and defense on RF identification tasks. [ABSTRACT FROM AUTHOR]

The almost-complete violation of Kirchhoff's law possesses various potential applications, such as nonreciprocal thermal emitters, thermal routers, and other logic devices. Recently, Weyl semimetal materials have attracted wide attention. It exhibits a very unusual and extremely large gyroscopic optical response within the mid IR without an external magnetic field, which is due to its unique topologically nontrivial electronic state and inherent time-reversal symmetry breaking. Here, we show a planar multilayer structure composed of Weyl semimetals, which can achieve an almost-complete violation of Kirchhoff's law at an incident angle of 18° without applying any external magnetic field. By tuning the thickness of the ITO layer, the angle of incidence, and the axial vector of the WSM, an almost complete violation of Kirchhoff's law can persist over a wide range of angles (18°–52.3°) and wavelengths (6.6 μm–7.2 μm). Furthermore, through the study of the electric field distribution, it is revealed that this enhanced nonreciprocity is due to the local field-enhancing properties of TPPs. Our work may contribute a practical design scheme for constructing strongly nonreciprocal thermal emitters. • Strong nonreciprocal thermal radiation was achieved at an incident angle of 18 ° without any external magnetic field. • The strong nonreciprocal thermal radiation is attributed to the local field enhancement characteristic of TPPs. • Almost completely violate Kirchhoff's law over broad angular and wavelength ranges. • The model is useful for design and application in nonreciprocal thermal emitters. [ABSTRACT FROM AUTHOR]

• A metamaterial-free and flexible THz sensor based on the N -CNTs was developed. • It realized high sensitivity detection and visible to the naked eye assay for NRIs. • It exhibited high sensitivity, simplicity, low cytotoxicity and good biocompatibility. • It was combined with smartphone-integrated sensing platform for real time analysis. • It was used potential applications for food safety and environment monitoring. With the rapid advances in terahertz (THz) spectroscopy, metamaterial-free THz sensors have been of importance due to efficient cost, high sensitivity and overcoming the limited tunability of the optical constants of metals. Here, a metamaterial-free and flexible THz sensor based on nitrogen-doping carbon nanotubes (N -CNTs) coupled with signal-enhancing Au NPs was proposed for detecting nereistoxin-related insecticides (NRIs). Sensitivity and selectivity for NRIs detection have been realized over the range of 3.3–100 μg/L with good linear fitting (R2 ≥ 0.9003) and LOD was 1.33 μg/L. Accuracy was validated by the recovery rates of 105.87–109.75% of NRI in spiked food-matrix sample. These results indicated the developed signal-enhancing THz method, validated by LC-MS/MS, exhibited high sensitivity and simplicity detection, which has noteworthy potential for applications in food safety and environment monitoring. [ABSTRACT FROM AUTHOR]

In the present work, the phase change material dodecanol (DD) and the polymer polyvinyl alcohol (PVA) was used as the oil phase and water phase, respectively, to prepare the oil-in-water (O/W) core-sheath structured nanofibers. The forming mechanism of the core-sheath structure of O/W emulsion electrospun nanofibers has been studied. During emulsion electrospinning, the oil phase droplets are polarized, stretched, deformed and merged under the dual action of water phase and electric field force, resulting in the phase separation within jet to form core-sheath structured fibers. Then, the influences of the contents of water phase and oil phase materials on the fiber structures and phase change performances were explored. With a water phase content ≥10 wt% and an oil phase content ≤8 wt%, the fibers can exhibit an obvious core-sheath structure. It was shown that the nanofibers prepared using 10 wt% PVA and 8 wt% DD have a phase transition enthalpy as high as 67 J/g and a good thermal cycle stability with a loss rate of melting enthalpy as low as 0.3%. The results reported would be useful for the phase change temperature regulation based on the emulsion electrospun core-sheath structured nanofibers. [Display omitted] • The model of the core-sheath structure forming mechanism have been established. • The influences of water phase and oil phase on the formation of core-sheath fibers have been studied. • The 8% PCM fibers show the greatest application potential in the field of phase change temperature regulation. [ABSTRACT FROM AUTHOR]

As a social withdrawal personality trait, shyness is usually considered irrelevant or negatively related to aggression. However, Zimbardo (1990) found that 70% of first-time violent offenders had the shyness trait. Existing studies have also shown that shy individuals are more aggressive. Therefore, the current study investigates the relationship between shyness and aggression and explores the underlying mechanism of this relationship in late childhood through environmental and individual factors. The Shyness Scale, Parent-Child Conflict Scale, Self-Control Scale, and Aggression Questionnaire were used to measure primary school students in grades 4–6 to investigate the mediating roles of parent-child conflict and self-control between children's shyness and aggression. The results showed that when the shyness level in late childhood was higher, the children's aggression was stronger, and parent-child conflict and self-control played multiple mediating roles between shyness and aggression. Our study deepens the understanding of the relationship between shyness and aggression in late childhood, and it provides an intervention direction and a theoretical basis for effectively preventing the aggression of shy children in late childhood. • The higher the level of shyness in children, the more aggressive they are. • Shy children show stronger aggressive cognition，aggressive emotion and aggressive behavior. • Parent-child conflict and self-control play multiple mediating roles between children's shyness and aggression. [ABSTRACT FROM AUTHOR]

• A more reasonale DC-AC-DC test was developed to accelerate the corrosion damage of organic coatings. • The new method accelerates the damage without changing the degradation mechanism. • The accelerated damage has the same morphology, composition and impedance behavior as natural immersion. The corrosion damage of an organic coating system was accelerated by different AC-DC-AC tests in comprison with neutral salt spray (NSS) and natural immersionn. Electrochemical impedance spectroscopy (EIS), optical microscopy, scanning electron microscopy (SEM), laser microscopy, adhesion measurement, and energy dispersive spectroscopy (EDS) was employed to reveal the degradation processes of the coating. The results showed that the corrosion damage could be rationally accelerated in the same way as that in natural immersion condition if an alternate anodic polarization and a cathodic polarization were included in the DC step during the AC-DC-AC test. The accelerated corrosion damage had the same electrochemical behavior, surface morphology and product composition as that in natural immersion. [ABSTRACT FROM AUTHOR]

• AMPK is a key regulator on multiple metabolic processes. • AMPK can be activated by phytochemicals to prevent chronic diseases. • Several environmental pollutants induce metabolic disorders by inhibiting AMPK. • AMPK pathway factors require more attention to help address metabolic disorders. AMPK is a key player in a variety of metabolic and physiological processes, which might be considered one of the most promising targets for both prevention and treatment of metabolic syndrome and its associated diseases. Many dietary components and contaminants have been recently demonstrated to prevent or promote the development these diseases via AMPK-mediated pathways. AMPK can be activated by diverse phytochemical substances such as EGCG, chicoric acid, tomatidine, and others, all of which have been found to contribute to preventing or ameliorating chronic disorders. On the other hand, recent studies have found that metabolic disruptions induced by pesticides such as 1,3-Dichloro-2-propanol, imidacloprid, permethrin, are attributed to the inactivation of AMPK. This review may contribute to the development of functional foods for treatment of metabolic syndrome and associated diseases through modulating AMPK pathway. [ABSTRACT FROM AUTHOR]

The twinning mechanism in an FeCoNiCrAl 0.1 high-entropy alloy was investigated by in-situ transmission electron microscopy. Deformation twins were commonly found on the conjugate plane and were produced by twinning dislocation gliding on every adjacent (111) plane layer by layer. The twinning dislocations were Shockley partials and were generated from the cross-slip. [ABSTRACT FROM AUTHOR]

Effective N-doped TiO 2 nanotube arrays with rutile–anatase mixed phase were fabricated by two-step anodization method and annealing in a NH 3 atmosphere. Compared with pure anatase TiO 2 nanotube arrays, the photocurrent density of N-doped TiO 2 nanotube arrays with mixed phase increased by about three times under visible light. Moreover, the open circuit potential of 304 stainless steel obviously negatively shifted when coupled with N-doped TiO 2 nanotube arrays with mixed phase under visible light. The enhancement was mainly because N-doping extends light absorbance and the mixed phase is beneficial for the separation of photoexcited electrons–holes. Therefore, N-doped TiO 2 nanotube arrays with mixed phase showed highly effective photogenerated cathodic protection of 304 stainless steel under visible light. Interestingly, the photoelectrode also displayed a cathodic protection effect after removing irradiation, which is meaningful for practical applications. Compared with pure anatase TiO 2 nanotubes array, the photocurrent density of N-m- TNT increases by about 3 times under visible light and show highly effective photogenerated cathodic protection of 304 stainless steel in 3.5 wt% NaCl solution under visible light illumination. [Display omitted] • N-doped TiO 2 nanotube arrays with anatase/rutile mixed phase were successfully fabricated by annealing at NH 3 atmosphere. • The composite photoanode exhibits visible light absorbance and enhanced charge separation efficiency. • The composite photoelectrode shows enhanced photoelectricity response under solar light (1 sun) and visible light. • The composite photoelectrode shows effective photogenerated cathodic protection of 304 stainless steel under visible light. [ABSTRACT FROM AUTHOR]

To improve the alternating current-direct current-alternating current (AC-DC-AC) coating evaluation technique, the single DC step in the AC-DC-AC method was replaced with a combination of cathodic and anodic polarization in this work. The modified alternate anodic and cathodic AC-DC-AC method experimentally proved to more reliably evaluate the protection performance of an acrylic varnish paint coating than the conventional AC-DC-AC test, as it could more rationally accelerate the coating degradation process without changing the mechanism of the coating corrosion damage. The corrosion damage and mechanism of the acrylic varnish paint coating/Q215 steel system was discussed in detail based on the results obtained from the modified AC-DC-AC tests. • Conventional AC-DC-AC test accelerates the corrosion damage of an organic coating system differently from that in natural exposure. • The combination of the anodic and cathodic polarization in the DC step of the AC-DC-AC cycle reasonably speeds up the corrosion damage. [ABSTRACT FROM AUTHOR]