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In this research, optical absorption regulation of Ag nanodisc arrays in a monolayer MoS2 hybrid system is investigated using the FDTD technique. Ag nanodisc arrays are designed on monolayer MoS2 on SiO2/Si and Au/SiO2 substrates. For Ag/1L MoS2/SiO2/Si, two absorption peaks near 620 nm and 670 nm are showed, with different intensification amplitudes of absorption peaks and slight shifts in peak position changing diameters or spacing of Ag nanodiscs. When the diameter is 220 nm, the strongest absorption peak is displayed at 745 nm. When the spacing s is 300 nm, the absorption peak at 759 nm has the highest intensity. When the thickness of the SiO2 film increases from 90 to 280 nm and 300 nm, the intensity of the absorption peak near 620 nm increases by 1.7 times, and the peak blueshifts to 585 nm. In the band from 550 to 700 nm, the presence of the Ag nanodisc array significantly enhances the absorption of the film system, when the thickness of the SiO2 film is 300 nm, and the enhancement amplitude of the absorption peak near 620 nm reaches three times. For Ag/1L MoS2/Au/SiO2, when the diameter or spacing of the Ag nanodisc increases from 100 to 220 nm every 30 nm, the peak positions of 620 nm and 670 nm are changed. When the diameter of the Ag nanodisc is 100 nm and 220 nm, the normalized absorption rates at 686 nm and 707 nm are 0.95 and 0.96, respectively. When the spacing s is 200 nm and 400 nm, the normalized absorption rates at 562 nm and 686 nm are 0.94 and 0.96, respectively. By comparing the optical absorption with and without the Ag nanodisc array, the absorption of the monolayer MoS2 hybrid system is greatly enhanced. When the surrounding medium is changed from air to water, the absorption peaks of 641 nm and 686 nm become 587 nm and 775 nm, the distance between peak positions is enlarged, and the intensity is obviously weakened, which is due to the weakening of the surface plasmon effect of the Ag nanodisc array. [ABSTRACT FROM AUTHOR]

Highlights: A flexible tribotronic artificial synapse with bioinspired neurosensory behaviour was demonstrated, which establishes an active interaction mechanism with the environment. The device can well exhibit tuneable synaptic behaviours by changing the mechanical input modes, including excitatory postsynaptic current, paired-pulse facilitation, and the hierarchical memorial process. The device has excellent mechanical flexibility that can exhibit stable synaptic functions even under strain conditions with a bending radius of 20 mm after 1000 bending cycles. As key components of artificial afferent nervous systems, synaptic devices can mimic the physiological synaptic behaviors, which have attracted extensive attentions. Here, a flexible tribotronic artificial synapse (TAS) with bioinspired neurosensory behavior is developed. The triboelectric potential generated by the external contact electrification is used as the ion-gel-gate voltage of the organic thin film transistor, which can tune the carriers transport through the migration/accumulation of ions. The TAS successfully demonstrates a series of synaptic behaviors by external stimuli, such as excitatory postsynaptic current, paired-pulse facilitation, and the hierarchical memory process from sensory memory to short-term memory and long-term memory. Moreover, the synaptic behaviors remained stable under the strain condition with a bending radius of 20 mm, and the TAS still exhibits excellent durability after 1000 bending cycles. Finally, Pavlovian conditioning has been successfully mimicked by applying force and vibration as food and bell, respectively. This work demonstrates a bioinspired flexible artificial synapse that will help to facilitate the development of artificial afferent nervous systems, which is great significance to the practical application of artificial limbs, robotics, and bionics in future. [ABSTRACT FROM AUTHOR]

• An intrinsically stretchable tribotronic mechanoplastic artificial synapse was proposed. • The device can be modulated by the triboelectric potential induced by mechanical stimulation. • The device establishes an active mechanically adjustable synaptic plasticity. Stretchable synaptic devices with adaptability to elastic deformation, sensing environmental stimuli, and unique information processing functions are of great significance for the development of the next generation of artificial nervous systems. Here, an intrinsically stretchable tribotronic mechanoplastic artificial synapse (STMAS) is proposed, which is integrated by a triboelectric nanogenerator and an electrolyte-gated transistor with ion-gel as dielectric layer. The STMAS can be modulated by the triboelectric potential induced by mechanical stimulation without the need to apply an external gate voltage, achieving an active mechanical tuning of synaptic plasticity such as excitatory postsynaptic current, paired-pulse facilitation, short-term plasticity, and long-term plasticity. The STMAS exhibits stable synaptic plasticity under 0–50% stretcher strain in parallel and vertical to channel directions, respectively. Furthermore, the International Morse code triggered by mechanical signals has been successfully mimicked. This work has achieved an intrinsically stretchable tribotronic artificial synapse with mechanically tuned synaptic behavior, which will help promote the development of artificial nervous systems and expand the applications of artificial synapses in intelligent robotics, artificial limbs and human–machine interaction. [ABSTRACT FROM AUTHOR]

The interplay of two linear controlled terms – fractional diffraction and parity-time (PT) symmetric lattice – gives rise to unique and interesting linear Bloch gap structures within where the nonlinear localized gap modes may exist. In this study, we explore the formation and dynamics of one-dimensional gap solitons in the cubic–quintic physical model combining the fractional diffraction and PT symmetric lattice. Two classes of gap solitons, which we name the fundamental gap solitons and dipole ones, are constructed and their stability regions within the first finite gap of the associated linear Bloch spectrum are identified by means of linear-stability analysis and direct perturbed numerical simulations. We stress that the gap solitons are always unstable under the condition of PT symmetry breaking (the imaginary part of which is above 0.5). The excitations of the stable two classes of gap solitons are also investigated by using the adiabatic variation of the system's parameters. The results predicted here shed some light on soliton physics in physical systems with combined fractional diffraction and PT symmetric lattice and the competing nonlinearities. • This study primarily investigated the impacts of the interaction between fractional diffraction and periodic lattices on nonlinear systems. • We proved that 0.5 is the critical value at which the spectrum of the linear Hamiltonian operator is entirely real. • We also studied the ground state and dipole solitons in nonlinear systems, their stability, and excitations of stable solitons. [ABSTRACT FROM AUTHOR]

Sesame (Sesamum indicum L.) is a valuable oilseed crop with numerous nutritional benefits containing a diverse range of bioactive compounds. However, sesame is also considered an allergenic food that triggers various mild to severe adverse reactions (e.g., anaphylaxis). Strict dietary avoidance of sesame components is the best option to protect the sensitized consumers. Sesame or sesame-derived foods are always consumed after certain food processing operations, which would cause a considerable impact on the structure of sesame proteins, changing their sensitization capacity and detectability. In the review, the molecular structure properties, and immunological characteristics of the sesame allergens were described. Meanwhile, the influence of food processing techniques on sesame proteins and the relevant detection techniques used for the sesame allergens quantification are also emphasized critically. Hopefully, this review could provide valuable insight into the development and management for the new "Big Eight" sesame allergen in food industry. • Sesame could trigger various mild to severe allergic reactions (e.g., anaphylaxis). • Structure properties and immunological characteristics of sesame allergens were described. • Effect of food processing on sesame proteins and detection techniques are discussed. • Novel detection and processing techniques are need for proper diagnosis. [ABSTRACT FROM AUTHOR]

Carbon materials have become a research hotspot in many fields because of their unique properties. In this paper, carbon nanowires (CNWs) were constructed with the finite-difference time-domain (FDTD) technique, and the effects of different structural parameters on the optical absorption properties of CNWS arrays at 350–810 nm were investigated. The results show that different lengths, diameters and spacings of the nanowires lead to different absorption properties of the arrays. In addition to a sharp decrease in the absorption at high incidence or viewing angles, the arrays have strong absorption properties at other angles. However, the array absorption at high incidence or viewing angles can be enhanced to some extent by varying the lengths of the nanowires. The wavelength and polarization direction of the excitation light have little effect on the absorption properties of the arrays. It is very important to determine the corresponding structural parameters of CNWs with the strongest absorption for the fabrication of nanowire arrays and their applications in stealth technologies, nanolight-emitting devices, photoelectric sensors and photovoltaic cells. [ABSTRACT FROM AUTHOR]

Secondary cooling electromagnetic stirring (S-EMS) significantly impacts the internal quality of continuous casting slabs. In order to investigate the effects of S-EMS modes on segregation in slabs, a three-dimensional numerical model of the full-scale flow field, solidification, and mass transfer was established. A comparative analysis was conducted between continuous electromagnetic stirring and alternate stirring modes regarding their impacts on steel flow, solidification, and carbon segregation. The results indicated that adopting the alternate stirring mode was more advantageous for achieving uniform flow fields and reducing the disparity in solidification endpoints, thus mitigating carbon segregation. Specifically, the central carbon segregation index under continuous stirring at 320 A was 1.236, with an average of 1.247, while under alternate stirring, the central carbon segregation index decreased to 1.222 with an average of 1.227. [ABSTRACT FROM AUTHOR]

Spontaneous symmetry breaking, a spontaneous course of breaking the spatial symmetry (parity) of the system, is known to exist in many branches of physics, including condensed-matter physics, high-energy physics, nonlinear optics, and Bose–Einstein condensates. In recent years, the spontaneous symmetry breaking of solitons in nonlinear wave systems is broadly studied; understanding such a phenomenon in nonlinear fractional quantum mechanics with space fractional derivatives (the purely nonlinear fractional systems whose fundamental properties are governed by a nonlinear fractional Schrödinger equation), however, remains pending. Here, we survey symmetry breaking of solitons in fractional systems (with the fractional diffraction order being formulated by the Lévy index α) of a nonlinear double-well structure and find several kinds of soliton families in the forms of symmetric and anti-symmetric soliton states as well as asymmetric states. Linear stability and dynamical properties of these soliton states are explored relying on linear-stability analysis and direct perturbed simulations, with which the existence and stability regions of all the soliton families in the respective physical parameter space are identified. [ABSTRACT FROM AUTHOR]

Self-trapped modes suffer critical collapse in two-dimensional cubic systems. To overcome such a collapse, linear periodic potentials or competing nonlinearities between self-focusing cubic and self-defocusing quintic nonlinear terms are often introduced. Here, we combine both schemes in the context of an unconventional and nonlinear fractional Schrödinger equation with attractive-repulsive cubic–quintic nonlinearity and an optical lattice. We report theoretical results for various two-dimensional trapped solitons, including fundamental gap and vortical solitons as well as the gap-type soliton clusters. The latter soliton family resembles the recently-found gap waves. We uncover that, unlike the conventional case, the fractional model exhibiting fractional diffraction order strongly influences the formation of higher band gaps. Hence, a new route for the study of self-trapped modes in these newly emergent higher band gaps is suggested. Regimes of stability and instability of all the soliton families are obtained with the help of linear-stability analysis and direct simulations. Stabilising localised solitons in higher dimensions is more challenging than their one dimensional counterpart due to the onset of critical collapse. Here, competing nonlinear terms are added to a linearly-modulated optical lattice to predict regimes of stability for different soliton families. [ABSTRACT FROM AUTHOR]

Gas pressure is one of the major factors to characterize the outburst danger of coal seams. Generally, the process of gas pressure determination is complicate and cannot ensure the accuracy of results, which may cause a wrong identification of outburst danger. This paper discussed and revealed a positive correlation between initial gas emission and gas pressure, which provides a new approach to identify the outburst danger by initial gas emission. Through theoretical analysis and numerical simulation, the liner equation of gas pressure and initial gas emission was deduced. Laboratory experiments under adsorption and desorption of CO2 and N2 were performed using coal samples from Weishe coal mine. The data of initial gas emission under different gas pressure were recorded, and the fitting curves were obtained. The results show a positive correlation between initial gas emission and gas pressure, and the curve of N2 was below the CO2. Especially, while the adsorption gas pressure was under 0.663 and 0.675 MPa, the difference of corresponding initial gas emission was only 0.01 L/s, which indicates the high degree of correlation. The results validated the theoretical and practical feasibility to identify the coal and the gas outbursts through initial gas emission. [ABSTRACT FROM AUTHOR]

Eucommia ulmoides Oliver seed oil, rich in polyunsaturated fatty acids (PUFAs), is susceptible to lipid oxidation in foods. Tea polyphenols (TPs) may effectively retard lipid oxidation in non-polar systems according to the polar paradox theory. In this study, we constructed a TPs-loaded water-in oil (W/O) microemulsion, which is a transparent, spontaneously formed, and thermodynamically stable colloidal system. This system consisted of E. ulmoides oil (38%, w/w), Span80, Tween 80, 1,2 propanediol, water, and TPs (3%, w/w). TPs were encapsulated in water cores of microemulsion, endowing this system with the higher oxidative stability and radical scavenging abilities. The accelerated oxidation assay demonstrated that low-dose TPs (<0.5%, w/w) were more effective in retarding lipid oxidation than that of high-dose TPs. Within 56 d, the peroxide value of TPs-loaded microemulsion increased to 16.479 meq/kg oil at 65 ℃ and that of E. ulmoides oil exceeded the Food Safety standards value within only 45 d. These findings indicate that TPs encapsulated into microemulsion effectively inhibit PUFA-rich oil oxidation. The nano-scale W/O dispersed system favors the protection and practical application of natural water-soluble antioxidants in PUFAs-rich lipid foods. [Display omitted] • TPs- E. ulmoides oil microemulsion was designed to allow sufficient dispersion of a polar antioxidant. • The system has nano-sized reverse micelles and excellent physicochemical stability. • This system can efficiently retard lipid oxidation and scavenge free radicals. [ABSTRACT FROM AUTHOR]

Abstract We propose a method to preliminarily determine the thicknesses of bulk MoS 2 layers based on their colours. The reflectance spectra of thin-layer and bulk MoS 2 on three substrates were calculated by using the finite-difference time-domain technique; then, based on chromaticity theory, the corresponding colour coordinates were obtained. By comparing the colours of the experimental sample and the corresponding structure, whose reflection spectrum was calculated, the thicknesses of bulk MoS 2 layers were determined preliminarily, which laid the foundation for the accurate measurement of the thickness, subsequently, through methods based on atomic force microscopy, Raman spectroscopy, and other linear and nonlinear optical processes. [ABSTRACT FROM AUTHOR]

The heat transfer of a slab is significantly influenced by roll contact during the continuous casting process. The influence of roll contact calculation methods on the predicted heat transfer results has not been previously investigated. In this work, the non-uniform solidification of the wide-thick slab was studied with a 2D heat transfer model using real roll contact method (R. method) and equivalent roll contact method (E. method). The predicted slab surface temperature and shell thickness were verified with the measured results of the infrared camera and nail shooting experiments, respectively. Then, the predicted heat transfer results (including the slab surface temperature, mushy region length, and solidification end position) for the wide-thick slab with different thicknesses and different casting speeds were calculated using the E. method and R. method, and the influence of these two roll contact methods on the predicted heat transfer results was discussed for the first time. The results show that both these two roll contact methods could be applied to accurately predict the slab surface temperature without considering the transient temperature dips in the roll–slab contact regions. However, the deviation of the predicted mushy region length and solidification end position using the E. method are obvious. Compared with the R. method, the predicted mushy region length obtained using the E. method is larger and the solidification end obviously subsequently moves along the casting direction. [ABSTRACT FROM AUTHOR]

The stabilization of one-dimensional solitons by a nonlinear lattice against the critical collapse in the focusing quintic medium is a challenging issue. We demonstrate that this purpose can be achieved by combining a nonlinear lattice and saturation of the quintic nonlinearity. The system supports three species of solitons, namely, fundamental (even-parity) ones and dipole (odd-parity) modes of on- and off-site-centered types. Very narrow fundamental solitons are found in an approximate analytical form, and systematic results for very broad unstable and moderately broad partly stable solitons, including their existence and stability areas, are produced by means of numerical methods. Stability regions of the solitons are identified by means of systematic simulations. The stability of all the soliton species obeys the Vakhitov-Kolokolov criterion. [ABSTRACT FROM AUTHOR]

Recent years have witnessed a staggering escalation in the power density of modern electronic devices. Because increasingly high power density accumulates heat, efficient heat removal has become a critical limitation for the performance, reliability, and further development of modern electronic devices. Thermal interface materials (TIMs) are widely employed between the two solid contact surfaces of heat sources and heat sinks to increase heat removal for electric devices. Composites of graphene and matrix materials are expected to be the most promising TIMs because of the remarkable thermal conductivity of graphene. Here, the recent research on the thermal properties of graphene filled polymer composite TIMs is reviewed. First, the composition of graphene filled polymer composite TIMs is introduced. Then, the synthetic methods for graphene filled polymer composite TIMs are primarily described. This study focuses on introducing the methods for improving and characterizing the thermal properties of graphene filled polymer composite TIMs. Furthermore, the challenges facing graphene filled poly­mer composite TIMs for thermal management applications in the modern electronic industry and the further progress required in this field are discussed. [ABSTRACT FROM AUTHOR]

• CN antigenicity can be effectively reduced by chymosin-papain hydrolysis. • Chymosin pretreatment led to higher accessibility at Tyr sites for papain hydrolysis. • Peptides over 8 amino acids of αs1 CN were decreased by the two-step hydrolysis. • Non-coagulation pre-treatment of chymosin accelerates the subsequent hydrolysis. Cow milk protein allergy (CMPA) induced by casein poses major health challenges that hinders the consumption of milk-based formulas. In this study, a novel sequential enzymatic hydrolysis catalysed by chymosin and papain was proposed to reduce casein antigenicity. Its effects on reducing casein antigenicity, structural properties and peptide profiles were evaluated by ELISA, multispectral techniques and peptidome analysis. It was revealed that the sequential enzymatic hydrolysis obtained a similarly residual antigenicity level in a shorter time (60 min) compared to papain-hydrolysis for 360 min. The hydrolysis-site at Tyr residues accessibility of papain was increased to 36.84 % by the chymosin pretreatment and it was significantly higher than 26.93 % obtained by only papain for 60 min. Moreover, the sequential enzymatic hydrolysis led to decrease in the large fragment peptides from αs1 casein. These findings suggested that the proposed sequential enzymatic hydrolysis can be exploited in the development of CMPA-free formulas. [ABSTRACT FROM AUTHOR]

Arginine methylation is a common post-translational modification and is critical for many cellular processes. Sfm1 is a novel arginine methyltransferase that contains a SpoU-TrmD ( SPOUT) domain, a typical fold known for RNA methylation, but acts on a ribosomal protein. The underlying mechanism is poorly understood. Here, we report cocrystal structures of Sfm1 in complex with various ligands. We found that a critical loop responsible for S-adenosyl- l-methionine ( SAM) binding adopts a different conformation from previous reports, and SAM appears to exhibit double conformations. Deletion of this loop greatly reduces the affinity of Sfm1 to SAM. Additionally, by comparison to closely related tRNA-methyltransferase Trm10, our structural analyses offer a good explanation why the two enzymes utilize distinct substrates, providing insights into the molecular mechanism. [ABSTRACT FROM AUTHOR]

• Interface interaction of αs1-CN binding to IgG was revealed by molecular simulation. • E77-Q97, Y154-T174, and N190-L198 were the main regions of αs1-CN binding to IgG. • The binding affinity of αs1-CN to IgG were mainly hydrogen bond and ionic bonds. • Papain can strongly reduce the antigenicity of αs1-CN by breaking the vital epitopes. αs1-Casein (αs1-CN) is a major cow milk allergen, while the tertiary structure of αs1-CN and conformational epitopes of αs1-CN have not been clarified. Here, a reasonable three-dimensional structure of αs1-CN was established using ab initio methods, and hot-spot residues and epitopes were investigated by combining molecular dynamics simulation, peptides synthesis, and ELISA. Obtained results demonstrated that the binding mechanism between αs1-CN and IgG was located on three main regions: a helical structure zone (E77-Q97), the flexible loop zone (Y154-T174), and a flexible C-terminal (N190-L198), mainly connecting via hydrogen bond and ionic bonds. The hydrolysates produced by papain with lowest antigenicity (12.43%), which could considerably destroy the essential epitopes of αs1-CN confirmed by epitope synthesis, and LC-MS/MS. The results reported herein would provide novel insights into the interface interactions between αs1-CN and IgG, and prove valuable for developing hypoallergenic infant-formula and peptide vaccines for allergen-specific immunotherapy. [ABSTRACT FROM AUTHOR]

The wearable tactile sensors have attracted great attention in the fields of intelligent robots, healthcare monitors and human-machine interactions. To create active tactile sensors that can directly generate electrical signals in response to stimuli from the surrounding environment is of great significance. Triboelectric nanogenerators (TENGs) have the advantages of high sensitivity, fast response speed and low cost that can convert any type of mechanical motion in the surrounding environment into electrical signals, which provides an effective strategy to design the self-powered active tactile sensors. Here, an overview of the development in TENGs as tactile stimulators for multifunctional sensing and artificial synapses is systematically introduced. Firstly, the applications of TENGs as tactile stimulators in pressure, temperature, proximity sensing, and object recognition are introduced in detail. Then, the research progress of TENGs as tactile stimulators for artificial synapses is emphatically introduced, which is mainly reflected in the electrolyte-gate synaptic transistors, optoelectronic synaptic transistors, floating-gate synaptic transistors, reduced graphene oxides-based artificial synapse, and integrated circuit-based artificial synapse and nervous systems. Finally, the challenges of TENGs as tactile stimulators for multifunctional sensing and artificial synapses in practical applications are summarized, and the future development prospects are expected. [ABSTRACT FROM AUTHOR]

The effective photonic control is one of the key issues in photo-physics. Significant advancement in photonic crystals, quantum optics, ultrafast optics as well as micro-nano-optics gives rise to new opportunities to manipulate the emission and propagation in optical fields, leading to a number of new and interesting discoveries, e.g., ultrashort light pulse storage and efficient energy conversion. This paper reviews the latest research progress in storage, release and energy conversion for ultrashort laser pulses in periodical arrays of absorbing medium. Techniques to fabricate such devices are also presented. [ABSTRACT FROM AUTHOR]

By means of standard Thomas–Fermi approximation, we present stable solutions of one- and two-dimensional (1D and 2D) multihump soliton structures, including 1D and 2D modulated solitons as well as 2D soliton clusters, supported by inhomogeneous defocusing nonlinear Kerr media. Such nonlinear settings may apply to nonlinear optics and Bose–Einstein condensates. All the 1D and 2D fundamental modes with different numbers of humps (for both modulated solitons and soliton clusters) are demonstrated to be robustly stable. Besides, the considered 2D nonlinear setting also supports a vast varieties of vortex modes—vortex soliton clusters. Such novel type of vortex soliton clusters is qualitatively different from the ordinary vortex clusters, on the account of the fact that the latter type is a single large soliton with several-vortex configurations inside it, while our predicted vortex clusters structures are composed of the arrays of unitary vortex solitons. Stability regions for all the soliton structures are identified via linear stability analysis and direct simulations. • Approximate analytical solutions of modulated solitons and soliton clusters under inhomogeneous defocusing nonlinear Kerr media are obtained. • The solutions are produced by means of the standard Thomas–Fermi approximation. • Modulated solitons, soliton and vortex clusters are demonstrated to be stable profiles under such inhomogeneous defocusing nonlinear media. • The modulated solitons, soliton and vortex clusters predicted here may be realized in experiments in nonlinear optics and Bose–Einstein condensates by means of the state of-the-art technologies. [ABSTRACT FROM AUTHOR]

Solitons in the fractional space, supported by lattice potentials, have recently attracted much interest. The limit of deep 1D and 2D lattices in this system is considered, featuring finite bandgaps separated by nearly flat Bloch bands. Such spectra are also a subject of great interest in current studies. The existence, shapes, and stability of various localized modes, including fundamental gap and vortex solitons, are investigated by means of numerical methods; some results are also obtained with the help of analytical approximations. In particular, the 1D and 2D gap solitons, belonging to the first and second finite bandgaps, are tightly confined around a single cell of the deep lattice. Vortex gap solitons are constructed as four‐peak "squares" and "rhombuses" with imprinted winding number S=1$S=1$. Stability of the solitons is explored by means of the linearization and verified by direct simulations. [ABSTRACT FROM AUTHOR]

Ultrasonic technology is often used to modify proteins. Here, we investigated the effects of ultrasound alone or in combination with other heating methods on emulsifying properties and structure of glycinin (11S globulin). Structural alterations were assessed with Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS–PAGE), intrinsic fluorescence spectroscopy, ultraviolet (UV) absorption spectroscopy, and Fourier transform infrared (FTIR) spectroscopy. The size distribution and zeta-potential of 11S globulin were evaluated with a particle size analyzer. An SDS-PAGE analysis showed no remarkable changes in the primary structure of 11S globulin. Ultrasound treatment disrupted the 11S globulin aggregates into small particles with uniform size, narrowed their distribution and increased their surface charge density. Fluorescent spectroscopy and second-derivative UV spectroscopy revealed that ultrasound coupled with heating induced partial unfolding of 11S globulin, increasing its flexibility and hydrophobicity. FTIR further showed that the random coil and α-helix contents were higher while β-turn and β-sheet contents were lower in ultrasound combined with heating group compared to the control group. Consequently, the oil-water interface entirely distributed protein and reduced the surface tension. Moreover, ultrasound combined with heating at 60 °C increased the emulsifying activity index and emulsifying stability index of 11S globulins by 6.49-folds and 2.90-folds, respectively. These findings suggest that ultrasound combined with mild heating modifies the emulsification properties of 11S globulin. [ABSTRACT FROM AUTHOR]

Two decades ago, standard quantum mechanics entered into a new territory called space‐fractional quantum mechanics, in which wave dynamics and effects are described by the fractional Schrödinger equation. Such territory is now a key and hot topic in diverse branches of physics, particularly in optics driven by the recent theoretical proposal for emulating the fractional Schrödinger equation. However, the light‐wave propagation in saturable nonlinear media with space fractional derivatives is yet to be clearly disclosed. Here, such nonlinear optics phenomenon is theoretically investigated based on the nonlinear fractional Schrödinger equation with nonlinear lattices—periodic distributions of either focusing cubic (Kerr) or quintic saturable nonlinearities—and the existence and evolution of localized wave structures allowed by the model are addressed. The model upholds two kinds of one‐dimensional soliton families, including fundamental solitons (single peak) and higher‐order solitonic structures consisting of two‐hump solitons (in‐phase) and dipole ones (anti‐phase). Notably, the dipole solitons can be robust stable physical objects localized merely within a single well of the nonlinear lattices—previously thought impossible. Linear‐stability analysis and direct simulations are executed for both soliton families, and their stability regions are acquired. The predicted solutions can be readily observed in optical experiments and beyond. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the mechanism of bone repair mediated by recombination BMP-2 (rhBMP-2)/recombination CXC chemokine ligand-13 (rhCXCL13)-loaded hollow hydroxyapatite (HA) microspheres/chitosan (CS) composite. Firstly, the biological activity of rhBMP-2 and rhCXCL13 released from the complex was investigated. Secondly, the effect of rhBMP-2 sustained release solution on ALP activity and rhCXCL13 sustained release solution on cell migration of rat bone marrow mesenchyme stem cells was tested. Thirdly, osteoblasts differentiation test, X-ray scoring and three-point bending test were performed. Finally, the mRNAs expression of osteogenic marker genes and the protein expression of Runx2 was tested by reverse transcription-polymerase chain reaction (RT-PCR) and western blotting (WB), respectively. RhBMP-2 could significantly promote the proliferation and differentiation, and RhCXCL13 could promote the migration of rat bone marrow MSCs. Detection of ALP activity and calcium salt deposition showed that rhBMP-2 and rhCXCL13 could significantly improve the biological activity and promote cell differentiation ability. X-ray scoring of radius and flexural strength test showed that rhBMP-2 and rhCXCL13 could promote bone healing and improve the bending resistance of bone tissue. The in vitro molecular experiments including RT-PCR and WB further demonstrated the roles of rhBMP-2 and rhCXCL13 in bone formation and bone repair. Our results indicated that the hollow HA microspheres/CS composite could be effective as a delivery vehicle for rhBMP-2 and rhCXCL13 in bone regeneration and bone repair. In this process, rhBMP-2 may promote bone regeneration by regulating bone marrow MSCs cells recruited by rhCXCL13. [ABSTRACT FROM AUTHOR]

β-Glucosidase is the rate-limiting component of a cellulase-hydrolyzing reaction. Thermostability and glucose-tolerance are two critical criteria of the enzyme, which practically determine its performance in industrial applications. In this study, a thermostable and glucose-tolerant β-glucosidase (named Bgl1317) belonging to the glycoside hydrolase family 1 was acquired from a metagenomic library of Turpan soil through functional screening. Bgl1317 showed excellent thermostability and glucose-tolerance and its crystal structure was subsequently determined at a high resolution. Rational design based on the structure was conducted, producing three beneficial mutations A397R, L188A and A262S. While A397R improved the cellobiose activity by 80%, L188A and A262S increased the IC 50 value of glucose from 0.8 to 1.5 M. The residues that may play a role in glucose-tolerance of GH1 β-glucosidases were summarized and the performances of glucose-tolerant β-glucosidases reported in recent years were discussed and compared. This study provides insights into enzymatic properties of Bgl1317 for engineering it into a powerful catalyst and β-glucosidases in general. [ABSTRACT FROM AUTHOR]

Ubiquitin E3 Ligase MARCH7 is involved in T cell proliferation and neuronal development. In our previous study, we demonstrated MARCH7 promoted malignant behavior of ovarian cancer via the nuclear factor (NF)-κB and Wnt/β-catenin signaling pathway. However, the expression and function of MARCH7 in cervical cancer remains unknown. The present study aimed to unravel the expression and function of MARCH7 in cervical cancer to elucidate its potential role in the diagnosis and pathogenesis of cervical cancer. Results indicated that the expression of MARCH7 was abnormally high in cervical cancer tissues than normal cervical tissues. However, silencing the expression of MARCH7 in HeLa cells resulted in decreased cell proliferation and invasion. Mechanistic investigations revealed that MARCH7 interacted with VAV2. Silencing the expression of MARCH7 in HeLa cells inhibited the VAV2-RAC1-CDC42 signaling pathway. Overall, the results of the present study identified MARCH7 as a candidate oncogene in cervical cancer, and a potential target for cervical cancer therapy. [ABSTRACT FROM AUTHOR]

The wyosine derivatives present at position 37 in transfer RNAs (tRNAs) are critical for reading frame maintenance. The methyltransferase Trm5a from Pyrococcus abyssi (PaTrm5a) plays a key role in this hypermodification process in generating m1G37 and imG2, two products of the wyosine biosynthetic pathway, through two methyl transfers to distinct substrates, but the mechanism is currently unknown. We report two cocrystal structures of PaTrm5a in complex with tRNAPhe and reveal the structural basis for substrate recognition, which was supported by in vitro activity assays. The crystal structures showed that the D1 domain of the enzyme undergoes large conformational changes upon the binding of tRNA. The deletion of this domain greatly reduces the affinity and activity of PaTrm5a toward its RNA substrate, indicating that the enzyme recognizes the overall shape of tRNA. Using the small-angle x-ray scattering technique and crystallographic analysis, we discovered that PaTrm5a adopts distinct open conformations before and after the binding of tRNA. Last, through structure comparison with its ortholog Methanococcus jannaschii Trm5b (MjTrm5b), we propose a reaction mechanism for the double methylation capability of this unique enzyme. [ABSTRACT FROM AUTHOR]

A series of direct‐current tribovoltaic nanogenerators (TVNGs) with high current density have been developed for energy harvesting and mechanical sensing recently, but the lead wires that need to be connected to two relatively moving parts have greatly restricted the application of TVNG. Herein, a freestanding‐mode TVNG (FTVNG) is proposed based on metal, p‐type silicon (p‐Si), and n‐type silicon (n‐Si). As the freestanding part of metal simultaneously rubs against p‐Si and n‐Si, opposite direct current (DC) outputs can be generated, thus forming a DC output from p‐Si to n‐Si in the external circuit. Resulting from the distinctive structure, FTVNGs are applicable for harvesting energy from moving objects without attached wires. Additionally, by using steel needles to precisely control the actual contact area, the electrical output characteristics and influence laws of the tribovoltaic effect under different working parameters such as area and speed are studied. Moreover, FTVNG is integrated into the traditional rolling bearing as a triboelectric bearing, realizing energy recovery from the rotational motion of mechanical parts and speed sensing, which demonstrates the great application potential of TVNG in basic components and parts. [ABSTRACT FROM AUTHOR]

Background. Cervical cancer (CC) is one of the most frequent female malignancy. Cancer stem cells (CSCs) positively affect survival outcomes in cancer patients, but in cervical cancer, the mechanism of tumor stem cells is still uncertain. Methods. RNA-seq data and related clinical follow-up of patients suffering from CC were from TCGA. Consensus clustering screened prognostic mRNAsi-related genes and identified molecular subtypes for CC. Based on the overlapping differentially expressed genes (DEGs) in subtypes, we employed LASSO and multivariate Cox regression to screen prognostic-related genes and established the RiskScore system. The patients were grouped by RiskScore, the prognosis was analyzed by the Kaplan-Meier (K-M) curve among the various groups, and the precision of the RiskScore was assessed by the ROC curve. Finally, the potential worth of RiskScore in immunotherapy/chemotherapy response was assessed by evaluating TIDE scores and chemotherapy drug IC 50 values. Results. We noticed that patients with low mRNAsi had a shorter survival and then identified three molecular subtypes (C1-3), with the C1 having the worst prognosis and the lowest mRNAsi. Finally, we identified 7 prognostic-related genes (SPRY4, PPP1R14A, MT1A, DES, SEZ6L2, SLC22A3, and CXCL8) via LASSO and Cox regression analysis. We established a 7-gene model defined RiskScore to predict the prognosis of CC patients. K-M curve indicated that low RiskScore patients had improved prognosis, and ROC curves indicated that RiskScore could precisely direct the prognostic evaluation for those suffering from the cancer. This was also confirmed in the GSE44001 and GSE52903 external cohorts. Patients were more sensitive to immunotherapy if with low RiskScore, and RiskScore exhibited precise assessment ability in predicting response to immunological therapy in CC patients. Conclusion. CC stemness is associated with patient prognosis, and the RiskScore constructed based on stemness characteristics is an independent prognostic index, which is expected to be a guide for immunotherapy, providing a new idea for CC clinical practice. [ABSTRACT FROM AUTHOR]

This paper describes the preparation of low-temperature sintered nanosilver paste with inverse microemulsion method with Span-80/Triton X-100 as the mixed-surfactant and analyzes the influence of different sintering parameters (temperature, pressure) on the shear properties of low-temperature sintering of nanosilver. Experimental results show that the shear strength of the low-temperature sintering of nanosilver increases as the temperature and pressure increase. But there are many pores and relative fewer cracks on the sintering layer after low-temperature sintered. The test thermal resistance of low-temperature sintered nanosilver paste is 0.795 K/W which is greater than SAC305 weld layer with a T3ster thermal analyzer. The adhesive performance and the heat dispersion of low-temperature sintered nanosilver paste need to be further researched and improved. [ABSTRACT FROM AUTHOR]

Spray drying is an efficient, rapid and relatively low-cost method for preparing microencapsulated lactic acid bacteria (LAB) in industry, but high temperature reduces the survival rate of LAB. Oil can polymerise with LAB by hydrophobicity and reduce the thermal and oxidative damage on bacteria during spray drying. However, oil is easily oxidised during spray drying, and its insolubility makes it difficult to evenly disperse the emulsion in the oil phase. In this comprehensive review, the oils used for LAB microcapsule and its protectional mechanism were discussed. And then wall materials and modification methods, which stabilizes co-microcapsule containing lactic acid bacteria and oil, is presented. Oils were a promising material for spray-dried LAB. Liquid oils with more unsaturated fatty acids reduced oxidative stress. Solid oils with high saturated fatty acid content are often added in the form of solid small particles, reducing the bacterial thermal damage by absorbing heat during spray drying. Appropriate wall materials and pre-treatment on oil-LAB co-microcapsule can reduce lipid oxidation, stabilize the emulsion and enhance the survival rate of lactic acid bacteria after spray drying. [Display omitted] • Oil provides a protective barrier to oxygen and heat. • The polysaccharide matrix forms a mesh gel that stabilizes bacteria. • Proteins unfold and reorient at the water-oil interface to stabilize the emulsion. • The survival rate of bacteria could be improved by wall material modification. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sarcoplasmic calcium-binding protein (SCP) was expressed, purified and identified. • The potential allergenicity and digestibility of heat-treated rSCP were examined. • The structural change of heat-treated rSCP was assessed by MD simulation analysis. • Autoclaved rSCP showed notable reduction in IgE reactivity and digestion stability. • Epitopes masking with protease sites exposed were confirmed in heat-treated rSCP. In the present study, sarcoplasmic calcium-binding protein (SCP) was first expressed in E. coli BL21 (DE3), and then identified based on immunoblotting and SCP amino acid sequencing of shrimp (Litopenaeus vannamei) using mass spectrometry (MS). The recombinant SCP (rSCP) was treated with different temperature conditions to investigate its immunological properties, in vitro digestibility and structural changes with enzyme-linked immunosorbent assay (ELISA), immunoblotting, spectrophotometry and molecular dynamics simulation techniques. The immunoglobulin (Ig) E-binding activity of the rSCP could remain stable until 80 °C, whereas the higher thermal processing temperatures resulted in a significant decrease in IgG/IgE-binding capacity coupled with alterations in the secondary and tertiary structures. Notably, the maximum reduction of IgG/IgE reactivity and in vitro digestibility were observed in the autoclaved rSCP. The decrease in the potential allergenicity of rSCP not only correlated well with the decreasing of α-helix, epitopes masking and exposure of more protease cleavage sites, but also with the destruction of Ca2+ binding sites due to the unfolding of the rSCP with heating treatments, which was supported by the thermal-induced changes of the secondary and tertiary structures. These findings indicate that autoclaved treatment may be an effective and promising approach for producing hypoallergenic seafood. [ABSTRACT FROM AUTHOR]

In this work, conical cavities with a fixed top diameter and varied bottom diameter have been utilized to improve the signal intensity, signal-to-noise ratio (SNR), and signal stability of laser-induced breakdown spectroscopy (LIBS). It is observed that the postponement of the maximum enhancement of spectral intensity and SNR occurs abnormally with decreasing the bottom diameter due to the energy dissipation from the plasma to the cavity walls. Optimization of the cavity size indicates that the conical cavity is superior to the widely-used cylindrical cavity in improving the performance of LIBS. It is also found that the emission enhancement in the conical cavity with larger bottom diameters is attributed to the increase in plasma temperature and electron number density, but the enhancement in the conical cavity with smaller bottom diameters is ascribed to the growth of electron number density. For the first time, the exact efficiencies of conical cavities suppressing the total number density fluctuation are acquired to evaluate the performance of improving signal stability through analysis of the signal uncertainty composition. [ABSTRACT FROM AUTHOR]

Based on the coupling effect of contact electrification and electrostatic induction, the triboelectric nanogenerator (TENG) as an emerging energy technology can effectively harvest mechanical energy from the ambient environment. However, due to its inherent property of large impedance, the TENG shows high voltage, low current and limited output power, which cannot satisfy the stable power supply requirements of conventional electronics. As the interface unit between the TENG and load devices, the power management circuit can perform significant functions of voltage and impedance conversion for efficient energy supply and storage. Here, a review of the recent progress of switching power management for TENGs is introduced. Firstly, the fundamentals of the TENG are briefly introduced. Secondly, according to the switch types, the existing power management methods are summarized and divided into four categories: travel switch, voltage trigger switch, transistor switch of discrete components and integrated circuit switch. The switch structure and power management principle of each type are reviewed in detail. Finally, the advantages and drawbacks of various switching power management circuits for TENGs are systematically summarized, and the challenges and development of further research are prospected. [ABSTRACT FROM AUTHOR]

Power management is an efficacious route to promote the development of triboelectric nanogenerators (TENGs), in which the buck switch for efficient energy extraction has always been a challenge. Here, we propose a three-port cantilever buck switch which can autonomously release energy from the TENG in maximum by the generated electrostatic field of the TENG. The influence of closing voltage of the buck switch on different structure parameters has been thoroughly investigated. The U-Q curve indicates that the optimal energy extraction can reach 90.86%, and the matched impedance of the TENG is reduced from 60 MΩ to 470 kΩ. Compared to the output power at matched impedance, the average power managed by this three-port cantilever buck switch is increased by 1.554 times, which can power the Bluetooth device, electronic watch, calculator and thermo-meter. This work has realized ultra-efficient power management of TENG by leveraging an autonomous cantilever buck switch, which can contribute to the efficient utilization of micromechanical energy. • A three-port cantilever buck switch controlled by the electrostatic field of the TENG for its power management is pioneered. • A detailed analysis of the force-electricity conversion process has been conducted. • U-Q curve and P-R curve has been linked to characterize the output efficiency for the first time. [ABSTRACT FROM AUTHOR]

The gas emission rate of boreholes is one of the most important indices for coal and gas outburst prediction. In this work, instantaneous gas emission velocity and environmental effects on borehole gas emission were studied. Through theoretical analysis, the mechanism of crack propagation in the coal borehole was clarified, and the effect of soft and hard coal on gas desorption and gas emission. The results of numerical simulations also indicated that the initial gas emission has a function relationship to the drilling distance and the physical characteristics of the coal seam. A novel dynamic testing technology was proposed to obtain gas emission velocity. Laboratory experiments under adsorption and desorption of CO2 and N2 were performed using coal samples from Xuehu, Fenghui, Weishe, and Wuzhong coal mines. The data of initial gas emission under different coal samples were recorded, and the fitting curves were obtained. The results show a positive correlation between initial gas emission and drilling depth. However, abnormal would occur when the drill pipe enters the soft stratification, and the maximum value of the initial gas emission of the abnormal part is 3.8 times the normal value, which indicates a high degree of sensibility to soft stratification. The results were revealed the dynamic gas emission law of boreholes. [ABSTRACT FROM AUTHOR]