With the deep popularity of mobile Internet, the "eyeball economy" is more active than ever. Driven by powerful modern media, livestreaming, as a new form of attracting public attention to obtain ...economic benefits, is worth studying its influence path on consumers. Based on the technology acceptance model and the mediating effect of emotion, this study constructs the consumer influencing factor model of livestreaming e-commerce. The research model and related hypotheses are verified by SPSS and linear multiple regression models. The research found that emotional trust and perceived emotional value could be regarded as mediating variables to stimulate consumers' purchase intention in livestreaming e-commerce. They have a full mediating effect on product and atmosphere and a partial mediating effect on homogeneity and promotion, which identifies that online celebrity's homogeneity, and sales promotion could influence consumers' purchase intention through the partial mediating role of emotional trust and perceived emotional value, while product and atmosphere induced by emotional contagion could exert influence on consumers' purchase intention through the full mediating effect of emotional trust and perceived emotional value.
Next-generation polarized mid-infrared imaging systems generally requires miniaturization, integration, flexibility, good workability at room temperature and in severe environments, etc. Emerging ...two-dimensional materials provide another route to meet these demands, due to the ease of integrating on complex structures, their native in-plane anisotropy crystal structure for high polarization photosensitivity, and strong quantum confinement for excellent photodetecting performances at room temperature. However, polarized infrared imaging under scattering based on 2D materials has yet to be realized. Here we report the systematic investigation of polarized infrared imaging for a designed target obscured by scattering media using an anisotropic tellurium photodetector. Broadband sensitive photoresponse is realized at room temperature, with excellent stability without degradation under ambient atmospheric conditions. Significantly, a large anisotropic ratio of tellurium ensures polarized imaging in a scattering environment, with the degree of linear polarization over 0.8, opening up possibilities for developing next-generation polarized mid-infrared imaging technology.
Magnetism in 2D has long been the focus of condensed matter physics due to its important applications in spintronic devices. A particularly promising aspect of 2D magnetism is the ability to ...fabricate 2D heterostructures with engineered optical, electrical, and quantum properties. Recently, the discovery of intrinsic ferromagnetisms in atomic thick materials has provided a new platform for investigations of fundamental magnetic physics. In contrast to 2D CrI3 and Cr2Ge2Te6 insulators, itinerant ferromagnetic Fe3GeTe2 (FGT), which has a larger intrinsic perpendicular anisotropy, higher Curie temperature (TC), and relatively better stability, is a promising candidate for achieving permanent room‐temperature ferromagnetism through interface or component engineering. Here, it is shown that the ferromagnetic properties of FGT thin flakes can be modulated through coupling with a FePS3. The magneto‐optical Kerr effect results show that the TC of FGT is improved by more than 30 K and that the coercive field is increased by ≈100% due to the proximity coupling effect, which changes the spin textures of FGT at the interface. This work reveals that antiferromagnet/ferromagnet coupling is a promising way to engineer the magnetic properties of itinerant 2D ferromagnets, which paves the way for applications in advanced magnetic spintronic and memory devices.
Significant enhancements of Curie temperature (TC) and coercive field (HC) are achieved in ultrathin Fe3GeTe2 (FGT) flakes by using the proximity effect between FGT and FePS3 (FPS). The TC is improved by more than 30 K and the HC is increased by ≈100%, which makes 2D FPS/FGT heterostructures promising candidates for applications in magnetic sensors and storage devices.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
•To the best of our knowledge, this is the first time that salient objects are detected based on extracting explicit material property embedded in the spectral responses via retrieval of endmembers ...and estimating their abundance.•The novelty also comes from adopting hyperspectral unmixing model as a preprocessing step for salient object detection. This allows the spatial distribution of endmembers be estimated, so the method is capable of dealing with mixed spectral responses in low spatial resolution hyperspectral images.•Different from existing hyperspectral salient object detection methods, we developed a novel method to fuse both local and global features for hyperspectral salient object detection.•We built a hyperspectral image dataset for salient detection, which contains mixed objects with similar color but different materials.
While salient object detection has been studied intensively by the computer vision and pattern recognition community, there are still great challenges in practical applications, especially when perceived objects have similar appearance such as intensity, color, and orientation, but different materials. Traditional methods do not provide good solution to this problem since they were mostly developed on color images and do not have the full capability in discriminating materials. More advanced technology and methodology are in demand to gain access to further information beyond human vision. In this paper, we extend the concept of salient object detection to material level based on hyperspectral imaging and present a material-based salient object detection method which can effectively distinguish objects with similar perceived color but different spectral responses. The proposed method first estimates the spatial distribution of different materials or endmembers using a hyperspectral unmixing approach. This step enables the calculation of a conspicuity map based on the global spatial variance of spectral responses. Then the multi-scale center-surround difference of local spectral features is calculated via spectral distance measures to generate local spectral conspicuity maps. These two types of conspicuity maps are fused for the final salient object detection. A new dataset of 45 hyperspectral images is introduced for experimental validation. The results show that our method outperforms several existing hyperspectral salient object detection approaches and the state-of-the-art methods proposed for RGB images.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
As one of the main functional substances, carbohydrates account for a large proportion of the human diet. Conventional analysis and detection methods of dietary carbohydrates and related products are ...destructive, time-consuming, and labor-intensive. In order to improve the efficiency of measurement and ensure food nutrition and consumer health, rapid and nondestructive quality evaluation techniques are needed. In recent years, terahertz (THz) spectroscopy, as a novel detection technology with dual characteristics of microwave and infrared, has shown great potential in dietary carbohydrate analysis. The current review aims to provide an up-to-date overview of research advances in using the THz spectroscopy technique in analysis and detection applications related to dietary carbohydrates. In the review, the principles of the THz spectroscopy technique are introduced. Advances in THz spectroscopy for quantitative and qualitative analysis and detection in dietary carbohydrate-related research studies from 2013 to 2022 are discussed, which include analysis of carbohydrate concentrations in liquid and powdery foods, detection of foreign body and chemical residues in carbohydrate food products, authentication of natural carbohydrate produce, monitoring of the fermentation process in carbohydrate food production and examination of crystallinity in carbohydrate polymers. In addition, applications in dietary carbohydrate-related detection research using other spectroscopic techniques are also briefed for comparison, and future development trends of THz spectroscopy in this field are finally highlighted.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
Independent vector analysis (IVA) and tensor decomposition are two types of effective algorithms for joint blind source separation (JBSS) with different statistical assumptions. Although IVA and ...tensor decomposition are intrinsically linked, their explicit connection has not been reported. In this letter, we reveal their explicit connection through a piecewise stationary multivariate complex Gaussian signal model. With this model, IVA can be explained as reconstructing the covariances of the mixtures in a similar manner as double coupled canonical polyadic decomposition (DC-CPD), a typical tensor-based algorithm, with the only difference being the distance metric used in the cost function. Numerical experiments show that IVA can achieve better separation performance but is highly dependent on how well the a priori model matches the actual signal, while DC-CPD is more robust to the model mismatch.
To improve the performance of conventional double-effect absorption refrigeration systems (DEARS), new series parallel (SP) and reverse parallel (RP) configurations using LiCl-H2O and LiBr-H2O as ...working fluids, combined with two vapor compressors (VC), are proposed and thermodynamically evaluated. The effects of the distribution ratio (D) and compression ratio (CR) on the system performance are discussed. The results reveal that both configurations can extend the operation ranges of DEARS effectively at a higher distribution ratio, and the performance for low-grade heat source utilization is improved substantially by the use of VC. The compressor positioned between the evaporator and absorber is superior to that between the high-pressure generator and low-pressure generator because of the better performance improvement and larger operating ranges. In all the examined cases, LiCl-H2O systems perform better than LiBr-H2O systems in terms of the coefficient of performance (COP) and exergetic efficiency. At the higher CR of approximately 2, the compression-assisted DEARS can be driven by heat sources below 100 °C with high levels of COPs above 1.16 for the LiBr-H2O working pair and 1.29 for the LiCl-H2O working pair. The system can operate at the optimum condition by adjusting the CR values according to the characteristics of the heat sources.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The serine/threonine-protein kinase general control nonderepressible 2 (GCN2) is a well-known stress sensor that responds to amino acid starvation and other stresses, making it critical to the ...maintenance of cellular and organismal homeostasis. More than 20 years of research has revealed the molecular structure/complex, inducers/regulators, intracellular signaling pathways and bio-functions of GCN2 in various biological processes, across an organism's lifespan, and in many diseases. Accumulated studies have demonstrated that the GCN2 kinase is also closely involved in the immune system and in various immune-related diseases, such as GCN2 acts as an important regulatory molecule to control macrophage functional polarization and CD4
T cell subset differentiation. Herein, we comprehensively summarize the biological functions of GCN2 and discuss its roles in the immune system, including innate and adaptive immune cells. We also discuss the antagonism of GCN2 and mTOR pathways in immune cells. A better understanding of GCN2's functions and signaling pathways in the immune system under physiological, stressful, and pathological situations will be beneficial to the development of potential therapies for many immune-relevant diseases.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Abstract
Graphene-based photodetectors have attracted significant attention for high-speed optical communication due to their large bandwidth, compact footprint, and compatibility with silicon-based ...photonics platform. Large-bandwidth silicon-based optical coherent receivers are crucial elements for large-capacity optical communication networks with advanced modulation formats. Here, we propose and experimentally demonstrate an integrated optical coherent receiver based on a 90-degree optical hybrid and graphene-on-plasmonic slot waveguide photodetectors, featuring a compact footprint and a large bandwidth far exceeding 67 GHz. Combined with the balanced detection, 90 Gbit/s binary phase-shift keying signal is received with a promoted signal-to-noise ratio. Moreover, receptions of 200 Gbit/s quadrature phase-shift keying and 240 Gbit/s 16 quadrature amplitude modulation signals on a single-polarization carrier are realized with a low additional power consumption below 14 fJ/bit. This graphene-based optical coherent receiver will promise potential applications in 400-Gigabit Ethernet and 800-Gigabit Ethernet technology, paving another route for future high-speed coherent optical communication networks.
Supported platinum intermetallic compound catalysts have attracted considerable attention owing to their remarkable activities and durability for the oxygen reduction reaction in proton-exchange ...membrane fuel cells. However, the synthesis of highly ordered intermetallic compound catalysts remains a challenge owing to the limited understanding of their formation mechanism under high-temperature conditions. In this study, we perform in-situ high-temperature X-ray diffraction studies to investigate the structural evolution in the impregnation synthesis of carbon-supported intermetallic catalysts. We identify the phase-transition-temperature (T
)-dependent evolution process that involve concurrent (for alloys with high T
) or separate (for alloys with low T
) alloying/ordering stages. Accordingly, we realize the synthesis of highly ordered intermetallic catalysts by adopting a separate annealing protocol with a high-temperature alloying stage and a low-temperature ordering stage, which display a high mass activity of 0.96 A mg
at 0.9 V in H
-O
fuel cells and a remarkable durability.
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