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Surface flashover is an inevitable insulation issue for basin-type insulators in gas-insulated switchgears/lines, which significantly challenges the reliability of the electrical power systems. Previous studies have indicated that polymer/semiconductor-filler composite coatings effectively improve the insulation properties; however, the influence mechanism of the coating materials on flashover has not been demonstrated from a molecular perspective. In this work, epoxy/silicon-carbide (EP/SiC) composites were coated onto an EP substrate. The energy-level structure, surface trap, surface charging, and DC flashover voltage in SF6/N2 were calculated and characterized, and the process by which the tailored molecular energy level influences surface charge transport and flashover characteristics was elucidated. The incorporating of SiC particles reduced the width of the bandgap and introduced shallow traps, which improved carrier mobility and surface conductivity. Quantitative analysis of charge transport indicated that the improved carrier mobility and reduced surface trap level accelerated the surface charge dissipation. This reduced the tangential electrical field distortion and surface charge density and further impeded gas ionization. When the SiC concentration was 15 wt%, the flashover performance improved by 20.88%. This study describes the mechanism by which the EP/SiC coating regulates the surface charge distribution to improve the surface flashover performance by establishing a relationship among the microscopic molecular energy-level structures, mesoscopic charge transport, and macroscopic discharge phenomena. [ABSTRACT FROM AUTHOR]

The development of a low-cost and multifunctional sensing and monitoring device would be a meaningful endeavor. In this research, a novel spirooxazine with a two double-bonded structure, designated as (1-butyl-3,3-dimethylspiro[indoline-2,3'-naphtho[2,1-b] [1, 4]oxazine]-5,8'-diyl)bis(methylene)bis(2-methylacrylate) (SO-DB), was successfully synthesized and incorporated as a functional cross-linker into a polyhydroxyethyl methacrylate hydrogel system. Notably, this hydrogel system based on a single responsive component exhibits photo-pH dual responsiveness, which avoids the addition of multiple components that may affect other properties of the hydrogel. Particularly, in comparison to traditional surface grafting and physical blending, crosslinking with SO-DB leads to the formation of a denser and stronger three-dimensional polymer network in the stimuli-responsive hydrogel. Under UV light irradiation, spirooxazine absorbs energy and undergoes cleavage of the Cspiro-O bond, transforming the molecule from a colorless closed-ring state to an open-ringed photomerocyanine (PMC) state. Under acidic conditions, hydrophobic spirooxazine undergoes a reversible protonation open-ring reaction, forming a stable intermediate form, a protonated photomerocyanine (PMCH). Furthermore, the addition of SO-DB as a crosslinking agent to the hydrogel system increases its stability and fatigue resistance, and maintains good repeatability over 24 light cycles and 7 pH cycles without performance loss. Such approach to generate stimulus-responsive hydrogels could have great potential in both wearable biosensors and food packaging field. [ABSTRACT FROM AUTHOR]

The maximum mass of neutron stars (M TOV) plays a crucial role in understanding their equation of state (EoS). Previous studies have used the measurements for the compactness of massive pulsars and the tidal deformability of neutron stars in binary neutron star (BNS) mergers to constrain the EoS and thus the M TOV. The discovery of the most massive pulsar, PSR J0952−0607, with a mass |$\sim 2.35\, {\rm M}_{\odot }$|⁠ , has provided a valuable lower limit for M TOV. Another efficient method to constrain M TOV is by examining the type of central remnant formed after a BNS merger. Gravitational wave (GW) data can provide the total mass of the system, while accompanying electromagnetic signals can help infer the remnant type. In this study, we combine all the previous constraints and utilize the observational facts that about 24 per cent of the short gamma-ray bursts are followed by an X-ray internal plateau, which indicate that roughly this fraction of BNS mergers yield supermassive neutron stars, to perform (Markov Chain) Monte Carlo simulations. These simulations allow us to explore the probability density distribution of M TOV and other parameters related to BNS mergers. Our findings suggest that M TOV is likely around |$2.49\!-\!2.52\, {\rm M}_{\odot }$|⁠ , with an uncertainty range of approximately [ |$-0.16$|⁠ , |$0.15\, {\rm M}_{\odot }$| ] ([ |$-0.28$|⁠ , |$0.26\, {\rm M}_{\odot }$| ]) at 1σ (2σ) confidence level. Furthermore, we examine the type of merger remnants in specific events like GW170817 and GW190425 to further constrain M TOV and other relevant parameters, which can help to understand the physical processes involved in BNS mergers. [ABSTRACT FROM AUTHOR]

As the most energetic explosions in the Universe, gamma-ray bursts (GRBs) are commonly believed to be generated by relativistic jets. Recent observational evidence suggests that the jets producing GRBs are likely to have a structured nature. Some studies have suggested that non-axisymmetric structured jets may be formed through internal non-uniform magnetic dissipation processes or the precession of the central engine. In this study, we analyze the potential characteristics of GRB afterglows within the framework of non-axisymmetric structured jets. We simplify the profile of the asymmetric jet as a step function of the azimuth angle, dividing the entire jet into individual elements. By considering specific cases, we demonstrate that the velocity, energy, and line-of-sight direction of each jet element can greatly affect the behaviour of the overall light curve. The radiative contributions from multiple elements may lead to the appearance of multiple distinct peaks or plateaus in the light curve. Furthermore, fluctuations in the rising and declining segments of each peak can be observed. These findings establish a theoretical foundation for future investigations into the structural characteristics of GRBs by leveraging GRB afterglow data. [ABSTRACT FROM AUTHOR]

Traditional transmission line fault diagnosis approaches ignore local structure feature information during feature extraction and cannot concentrate more attention on fault samples, which are difficult to diagnose. To figure out these issues, an enhanced feature extraction-based attention temporal convolutional network (EATCN) is developed to diagnose transmission line faults. The proposed EATCN suggests a new comprehensive feature-preserving (CFP) technique to maintain the global and local structure features of original process data during dimension reduction, where the local structure-preserving technique is incorporated into the principal component analysis model. Furthermore, to diagnose transmission line faults more effectively, a CFP-based attention TCN scheme is constructed to classify the global and local structure features of a fault snapshot dataset. To be specific, to cope with the gradient disappearance problem and improve learning capability, a skip connection attention (SCA) network is developed by incorporating a skip connection structure and two fully connected layers into the existing attention mechanism. By combining the developed SCA network with the conventional TCN's residual blocks, an EATCN-based diagnosis model is then constructed to dynamically pay attention to various imported global and local structure features. Detailed experiments on the datasets of the simulated power system are performed to test the effectiveness of the developed EATCN-based fault diagnosis scheme. [ABSTRACT FROM AUTHOR]

The formation of black hole–neutron star (BH–NS) or BH–BH systems may be accompanied by special supernova (SN) signals, due to the accretion feedback from the companion BH. The additional heating, which is mainly attributed to the Blandford–Payne mechanism, would disrupt the isotropic nature of the luminosity distribution on the surface of the SN ejecta, leading to the appearance of polarization. Here we develop a three-dimensional Monte Carlo polarization simulation code to conduct simulations for these special SNe. We find that the maximum polarization level of ∼2% occurs at the peak time of SN emission in the "close-binary" scenario, while in the "faraway-binary" case maximum polarization (i.e., ∼0.7%) is observed at a considerably later time than the peak of the SN. The magnitude of polarization is dependent on the degree of unevenness in the luminosity distribution and the angle between the line of sight and the equatorial direction. When considering the geometric distortion of SN ejecta at the same time, the magnitude of polarization may either increase (for a oblate ellipsoidal shape) or decrease (for a prolate ellipsoidal shape). The polarization signatures represent a promising auxiliary instrument to facilitate the identification of the companion-fed SNe. Moreover, comparing the event rate of these special SNe with the event rate density of LIGO-Virgo-detected BH–NS/BH systems could further help to distinguish the BH–NS/BH formation channel. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD) seriously affects patient's life. A systematic summary of the latest epidemic trend and pathogenesis of IBD is lacking. In addition, some health benefits of lactic acid bacteria (LAB) were reported, whereas a comprehensive review of its mechanisms for alleviating IBD is limited. This review systematically revealed the epidemic trend and pathogenesis of IBD, and showed the potential regulatory mode of LAB on gut health, then critically exhibited the possible mechanisms of LAB in alleviating IBD based on animal and clinical studies. Moreover, it pointed out the challenges and opportunities of LAB for IBD. Higher incidences and death rates of IBD were found in developed countries. Environmental and genetic factors are important factors for the occurrence of IBD. LAB provided numerous advantages and had great potential for improving IBD as its ability to produce bioactive metabolites, regulate gut immunity, protect the intestinal mechanical barriers, inhibit oxidative damage, and restore unbalanced gut microbiota. Then, the manuscript advice to screen effective LAB by cell models and metabolites, to control the optimal intake of LAB through dose-effect studies, to encapsulate LAB through nanoencapsulation and microencapsulation to improve utilization, to promote the understanding of LAB by investigating the mechanism, and to improve the design of the clinical study to improve the lives of patients. This will contribute to understanding the epidemic trend, pathogenesis, and treatment of IBD, and promote the development of targeted therapeutic products such as LAB. • Higher incidences and death rates of IBD were found in developed countries. • The intestinal mucosal barrier is an important target for regulating IBD. • LAB have potential benefits to human health. • LAB alleviate IBD by improving the intestinal mucosal barrier. • LAB are helpful for adjuvant therapy of IBD patients. [ABSTRACT FROM AUTHOR]

Radix aconiti carmichaeli is a widely used traditional Chinese medicine that has been found to be effective in treating cardiovascular diseases and metabolic disorders. Patients with these diseases often experience a heat generation disorder, which is characterized by chilliness and can worsen the progression of the disease. This study established an in vitro screening model combining the examination of cellular mitochondrial membrane potential and mitochondrial temperature to screen drugs with thermogenic activity. After differentiation and determination of the content of characteristic metabolites of the drug-containing serum blood components, it was found that Fuziline (FZL) is the key thermogenic property in Radix aconiti carmichaeli, responsible for its thermogenic effects with a high relative importance of 33%. Experiments were conducted to evaluate the thermogenic activity of Radix aconiti carmichaeli and FZL in vivo by assessing temperature changes in various organs, including the rectum, liver, and brown adipose tissue. Moreover, the effects of intracellular β3-adrenergic receptor (β3-AR) agonistic effects were evaluated using transient β3-AR transfection and dual-luciferase assay systems. The molecular mechanism by which FZL promotes thermogenesis and improves mitochondrial function was investigated by verifying the β-adrenergic receptors (β-AR) downstream signaling pathway. The results suggest that FZL activates β-AR nonselectively, which in turn activates the downstream cAMP-PKA signaling pathway and leads to an increase in liver glycogenolysis and triglyceride hydrolysis, accompanied by enhancing mitochondrial energy metabolism. Consequently, the liver and brown adipose tissue receive energy to generate heat. In summary, these findings provide insight into the therapeutic application of Radix aconiti carmichaeli for metabolic disorders associated with heat generation disorders. [ABSTRACT FROM AUTHOR]

CO2 adsorption is one of the promising CCS technologies, and activated coke is a solid adsorbent with excellent adsorption properties. In this study, activated coke was prepared by using bituminous coal and coconut shells activated with KOH or CaCl2 in a physically activated atmosphere and modified with ammonia. The effect of the active agent impregnation ratio on the physicochemical properties of activated coke was investigated by N2 adsorption isotherms, scanning electron microscopy (SEM) and Fourier transform infrared spectrometry (FTIR). The CO2 adsorption performance of activated coke was tested, and the effect of nitrogen-containing functional groups on CO2 adsorption was investigated by experiments and simulations. The results showed that the specific surface area of activated coke reached 629.81 m2/g at a KOH impregnation ratio of 0.5 and 610.66 m2/g at a CaCl2 impregnation ratio of 1. The maximum CO2 adsorption capacity of activated coke reached 71.70 mg/g and 90.99 mg/g for conventional power plant flue gas and oxy–fuel combustion flue gas, respectively. After ammonia modification, the CO2 adsorption capacity of activated coke was further increased. Simulations showed that pyrrole and pyrrole functional groups changed the polarity of graphene and established weak interactions with CO2. [ABSTRACT FROM AUTHOR]

Recently, some gamma-ray bursts (GRBs) whose light curves consist of repeating emission episodes with similar temporal profiles have attracted extensive attention. They are proposed to be candidates of millilensing events, although smoking gun evidence is lacking, since there are no redshift measurements and no angular offset detections for any of these candidates. Here we show that without invoking gravitational lensing, the repeating light-curve properties of these GRBs could also be interpreted under the jet precession model, as long as the detectable period in every precession circle is less than the precession period, and the precession period is close to the jet emission duration. By fitting the gamma-ray light curves of these GRBs, we suggest that the jet precession angle for these bursts should be relatively small (e.g., θ p < 5.°3), and the jet structure for these bursts are more likely Gaussian. The results suggest us to be careful when identifying millilensing GRBs. Multiband afterglow data and especially angular offset detections are essential to provide comprehensive justification for this identification. [ABSTRACT FROM AUTHOR]

GRB 221009A is a bright gamma-ray burst (GRB) with isotropic energy larger than 1054 erg. Its fairly low redshift makes it a promising candidate for high-energy neutrino detection. However, a neutrino search for this GRB reported by the IceCube collaboration yielded a null result. In this paper, we utilize the upper limit from the IceCube observation to test different GRB prompt emission models. We find that, at least for this specific burst, the dissipative photosphere model could be ruled out in a large parameter space. The internal-shock model can survive only with a large bulk motion Lorentz factor Γ, where the most stringent and conservative constraints are Γ > ∼ 450 and Γ > ∼ 200, respectively. Also, the ratio of the total dissipated energy that goes into the protons and electrons (ϵ p / ϵ e ) can be constrained with a given Γ. For Γ < 400, ϵ p / ϵ e < 10 is required. For the Internal-collision-induced Magnetic Reconnection and Turbulence (ICMART) model, the constraint from GRB 221009A is modest. Under the ICMART model, only for extreme situations when most dissipated energy deposit into protons and all accelerated protons are suitable for producing neutrinos, a slightly large bulk motion (Γ > ∼ 250) is required. [ABSTRACT FROM AUTHOR]

The detailed chemical reaction mechanism of high temperature pyrolysis is constructed through the comparison of various current reaction mechanisms and sub‐models. This mechanism can better predict the formation of polycyclic aromatic hydrocarbons. Through path analysis, the interrelationship of the growth mechanisms of polycyclic aromatic hydrocarbons is expounded. And the important contribution pathways of five‐membered/six‐membered rings at high temperatures are investigated. Through component flux analysis and sensitivity analysis, the results show that the main formation path of the external five‐membered ring is the acetylene addition of naphthalene. Its stability decreases with increasing temperature and is the main introduction route of molecular curvature during low temperature pyrolysis. However, the embedded five‐membered ring obtained by benzene cycloaddition is less affected by temperature and is the most important chemical reaction process introduced by high temperature molecular curvature. The hydrogen abstraction acetylene addition mechanism still plays a dominant role at different temperatures and is a classical pathway for the formation of six‐membered rings. By cooperating with multiple reaction mechanisms, the formation mechanism of polycyclic aromatic hydrocarbons at different temperatures can be well predicted. [ABSTRACT FROM AUTHOR]

As a frontier imaging technique for biomedical applications, photoacoustic (PA) imaging has been developed rapidly. The development of new design strategies and excellent PA imaging reagents to boost PA conversion is eagerly desirable for high quality PA imaging but complicated to realize. Herein, we develop a new strategy in which PA imaging reagents with better properties can be easily optimized by polymerization. A series of new PA imaging reagents were designed and synthesized. The polymerization strategy can effectively promote the PA signal by specifically increasing the thermal-to-acoustic conversion efficiency. As these materials shared the same building units, the optimized effectiveness of polymerization strategy in terms of near-infrared light-harvesting capacity and thermal-to-acoustic conversion efficiency are discussed, rationally. The polymers with intense intramolecular motion exhibit an amplified PA signal by elevating thermal-to-acoustic conversion and its higher light-harvesting capability at redshifted region. The simultaneously strong PA signal and photothermal conversion efficiency of p-TTmB NPs enable precise PA imaging and effective photothermal therapy. This work highlights a simple and available design guideline of polymerization for amplifying the PA effect and optimizing existing materials. [ABSTRACT FROM AUTHOR]

The efficient utilization of energy in rich fuel detonation processes and the effective control method of soot are important topics in combustion research. In this paper, we numerically study the detonation wave behavior of acetylene–air systems in rich fuel condition by using a reduced reaction mechanism. The non-stiff terms of the governing equations are solved explicitly using the gas kinetic scheme, and the stiff terms are solved implicitly. Our results show that the acetylene pyrolysis is the dominant reaction process. The oxidation reaction is exploited to initiate the reaction induction process, providing the required energy to overcome the potential energy barrier. The secondary detonation structure is due to the stable interaction of the transverse waves and the combined action of the vinyl reaction system, thus effectively improve the energy release rate and providing a powerful solution for the fuel-rich high-energy release of advanced heat engines. The area of the unreacted pocket increases with the acetylene concentration, resulting in an irregular wave-front and detonation cell. The reflected shock wave impacting on the wall induces the secondary reaction of the detonation products. The concentration of polycyclic aromatic hydrocarbons decreases significantly and regenerates near the wall. Our approach provides an effective tool for controlling detonation soot and the preparation of carbon particles. [ABSTRACT FROM AUTHOR]

As the only known intelligent civilization, human beings are always curious about the existence of other communicating extraterrestrial intelligent civilizations (CETIs). Based on the latest astrophysical information, we carry out Monte Carlo simulations to estimate the number of possible CETIs within our Galaxy and the communication probability among them. Two poorly known parameters have a great impact on the results. One is the probability of life appearing on terrestrial planets and eventually evolving into a CETI (f c ), and the other determines at what stage of their host star’s evolution CETIs would be born (F). In order to ensure the completeness of the simulation, we consider a variety of combinations of f c and F. Our results indicate that for optimistic situations (e.g., F = 25% and f c = 0.1%), there could be 42,777 âˆ' 369 + 267 CETIs and they need to survive for 3 âˆ' 2 + 17 yr ( 2000 âˆ' 1400 + 2000 yr) to achieve one-way communication (two-way communication). In this case, human beings need to survive 0.3 âˆ' 0.298 + 0.6 Myr to receive one alien signal. For pessimistic situations (e.g., F = 75% and f c = 0.001%), only 111 âˆ' 17 + 28 CETIs could be born and they need to survive for 0.8 âˆ' 0.796 + 1.2 Myr ( 0.9 âˆ' 0.88 + 4.1 Myr) to achieve one-way communication (two-way communication). In this case, human beings need to survive 50 âˆ' 49.6 + 250 Myr to receive one signal from other CETIs. Our results may quantitatively explain why we have not detected any alien signals so far. The uncertainty of the results has been discussed in detail and would be alleviated with the further improvement of our astronomical observation ability in the future. [ABSTRACT FROM AUTHOR]

Background: Iron deficiency (ID) impairs patient physical activity, recognition and life quality, which is difficult to perceive but should not be underestimated. Worldwide efforts have been made to lower ID burden, however, whether it decreased equally in different regions and sexes is unclear. This study is to examine regional and sex inequalities in global ID from 1990 to 2017. Methods: We conducted a longitudinal, comparative burden-of-disease study. Disability-adjusted life-years (DALYs) of ID were obtained from Global Burden of Disease Report 2017. Human Development Index (HDI) data were obtained from Human Development Report 2017. Gini coefficient and the concentration index were calculated to assess the equities in global burden of ID. Results: A downward trend of global ID burden (from 569.3 (95% Uncertainty Interval [UI]: 387.8–815.6) to 403.0 (95% UI: 272.4–586.6), p < 0.001), age-adjusted DALYs per 100,000 population) but an uptrend of its inequalities (from 0.366 to 0.431, p < 0.001, Gini coefficients) was observed between 1990 and 2017. ID burden was heavier in women than that in men ([age-adjusted DALYs per 100,000 population from 742.2 to 514.3] vs [from 398.5 to 291.9]), but its inequalities were higher in men since 1990. The between-sex gap of ID burden was narrowed with higher HDI (β = − 364.11, p < 0.001). East Asia & Pacific and South Asia regions made a big stride for ID control in both sexes over decades [age-adjusted DALYs per 100,000 population from 378.7 (95% UI: 255.8–551.7) in 1990 to 138.9 (95%UI: 91.8–206.5) in 2017], while a heavy burden among Sub-Saharan African men was persistent[age-adjusted DALYs per 100,000 population, 572.5 (95% UI: 385.3–815) in 1990 and 562.6 (95% UI: 367.9–833.3) in 2017]. Conclusions: Redistributing attention and resources to help countries with low HDI, especially take care of women with low socioeconomic status (SES) and men under high ID burden may help hold back the expanding ID inequality. [ABSTRACT FROM AUTHOR]

Effective sound energy transmission and beam manipulation through stiff and dense materials such as metal remain daunting tasks. It is in part attributable to the vast impedance mismatch between those materials and ambient media. Adding openings may facilitate to better bridge energy over, yet ineffective in many applications and may also damage the structural integrity. Here, we present an auxiliary ultrasound focusing meta-lens for stiff and dense materials. It offers significantly enhanced ultrasound transmission and focusing through a stiff metal plate yet without enforcing any through holes or openings. The simple, one-sided only meta-structures are designed and optimized by an inverse strategy based on the genetic algorithm. We numerically and experimentally demonstrate the much enhanced ultrasound transmission when the meta-lens is added to a flat brass plate, along with the capability to offer simultaneous ultrasound focusing. This design methodology can be easily extended to deal with more complex shaped target in a straightforward manner, offering a practical solution to the efficient tunneling of ultrasound energy through stiff and dense materials. With simple grating structures, the meta-lens can be easily fabricated, showing great application prospects in medical imaging and disease treatment. [ABSTRACT FROM AUTHOR]

In this paper, we simulate the prompt emission light curve, spectrum, and E p evolution patterns of gamma-ray bursts (GRBs) within the framework of the Internal-collision-induced Magnetic Reconnection and Turbulence (ICMART) model. We show that this model can produce a Band-shaped spectrum, whose parameters (E p, α, β) could follow the typical distribution of GRB observations, as long as the magnetic field and the electron acceleration process in the emission region are under appropriate conditions. On the other hand, we show that for one ICMART event, E p evolution is always a hard-to-soft pattern. However, a GRB light curve is usually composed of multiple ICMART events that are fundamentally driven by the erratic activity of the GRB central engine. In this case, we find that if one individual broad pulse in the GRB light curve is composed of multiple ICMART events, the overall E p evolution could be disguised as an intensity-tracking pattern. Therefore, mixed E p evolution patterns can coexist in the same burst, with a variety of combined patterns. Our results support the ICMART model as a competitive model to explain the main properties of GRB prompt emission. The possible challenges faced by the ICMART model are also discussed in detail. [ABSTRACT FROM AUTHOR]

Background: Culex pipiens quinquefasciatus Say (Cx. quinquefasciatus) and Culex pipiens form molestus Forskal (Cx. molestus) in the Culex pipiens complex group show considerable differences in host seeking, blood feeding, mating behavior and in vector competence. Blood-feeding mosquito behaviors are closely related to their olfactory gene expression and olfactory gene repertoire composition. Comparing olfactory genes between these two subspecies with significantly different blood-feeding behaviors can support further research on the molecular mechanism of the Culex pipiens complex olfactory sensory system, providing a new approach for determining candidate attractant or repellent compounds. Methods: Non-blood-feeding (NBF) and post-blood-feeding (PBF) olfactory system transcriptomes of the two subspecies were sequenced, and the biological functions of their differentially expressed genes were described by bioinformatics analysis. A quantitative polymerase chain reaction (qPCR) was applied to validate the RNA-seq data. The roles of particular olfactory receptors in Cx. quinquefasciatus blood-feeding behaviors were evaluated by RNAi. Results: Five, 7, 24, and 3 Cx. quinquefasciatus-specific OBPs, Cx. molestus-specific OBPs, Cx. quinquefasciatus-specific ORs and Cx. molestus-specific ORs were identified, respectively. The majority of selected ORs were consistent with the predicted transcriptome sequencing results after qRT-PCR validation. OR5 was expressed only in Cx. quinquefasciatus, and OR65 was the only gene upregulated after blood feeding in Cx. molestus. The blood-feeding rates of the OR5 and OR78 dsRNA groups were significantly lower (4.3%±3.1% and 13.3%±11.5%) than those of the enhanced green fluorescence protein (EGFP) group (64.5%±8.7%). Conclusion: Most OBPs and ORs were expressed in both subspecies but showed divergence in expression level. OR5 and OR65 might be species-specific expressed genes that regulate the olfactory behaviors of Cx. quinquefasciatus and Cx. molestus, respectively. The RNA interference of OR5 and OR78 could inhibit the blood-feeding behavior of Cx. quinquefasciatus, providing new targets for screening effective repellent compounds to control mosquito-borne diseases effectively and efficiently. Author summary: The transcriptomic gene expression of the olfactory tissues of Cx. quinquefasciatusthe and Cx. molestus differ significantly. The majority of ORs and OBPs are expressed in both subspecies but are clearly differentiated in expression level. OR5 and OR65 may be species-specific olfactory genes expressed in Cx. quinquefasciatus and Cx. molestus, respectively. After the microinjection of OR5-dsRNA and OR78-dsRNA into female Cx. quinquefasciatus adults, the blood-feeding rate was significantly lower than that of the control group, suggesting that OR5 and OR78 are associated with the blood-feeding behavior of Cx. quinquefasciatus. [ABSTRACT FROM AUTHOR]

Photochromic materials with stable properties during long-term use have a very broad application prospect. Herein, five kinds of spirooxazines (SO1-SO5) with antioxidant properties were successfully synthesized by blending and covalently bonding antioxidants. Then various photochromic polyacrylate laminating adhesives (PA1-PA7) with good fatigue resistance were prepared by incorporating spirooxazines into polyacrylate. Among them, this study used 2, 6 -di-tert-butyl-4-methylphenol (BHT) as the main antioxidant, and tris (2, 4-di-tert-butylphenyl) phosphite (168) as the auxiliary antioxidant. Upon ultraviolet (UV) activation, these PA films possessed superior photochromism and light responsiveness. Importantly, unlike traditional physical blending photochromic polymers, SO2 was successfully covalently bonded into PA through reaction (PA6), effectively improving the fatigue resistance and thermal stability of the PA film. Doping with BHT, it further improved the photochromic properties of the compound film (PA7). [ABSTRACT FROM AUTHOR]

Technologies enabling passive daytime radiative cooling and daylight harvesting are highly relevant for energy-efficient buildings. Despite recent progress demonstrated with passively cooling polymer coatings, however, it remains challenging to combine also a passive heat gain mechanism into a single substrate for all-round thermal management. Herein, we developed an optical wood (OW) with switchable transmittance of solar irradiation enabled by the hierarchically porous structure, ultralow absorption in solar spectrum and high infrared absorption of cellulose nanofibers. After delignification, the OW shows a high solar reflectance (94.9%) in the visible and high broadband emissivity (0.93) in the infrared region (2.5–25 μm). Owing to the exceptional mass transport of its aligned cellulose nanofibers, OW can quickly switch to a new highly transparent state following phenylethanol impregnation. The solar transmittance of optical wood (OW-II state) can reach 68.4% from 250 to 2500 nm. The switchable OW exhibits efficient radiative cooling to 4.5 °C below ambient temperature in summer (cooling power 81.4 W m−2), and daylight heating to 5.6 °C above the temperature of natural wood in winter (heating power 229.5 W m−2), suggesting its promising role as a low-cost and sustainable solution to all-season thermal management applications. • Combining phenylethanol and delignified wood was first achieved with switching between radiative cooling and solar heating. • The OW exhibits efficient radiative cooling to 4.5°C below ambient temperature in summer (cooling power = 81.4 W m−2).• • The OW exhibits daylight heating to 5.6 °C above the temperature of natural wood in winter (heating power = 229.5 W m−2). • Delignification and solvent impregnation are used to achieve cyclic thermal management properties. • The material we used — wood is obviously green, renewable and degradable. [ABSTRACT FROM AUTHOR]

A newly born millisecond magnetar is thought to be the central engine of some gamma-ray bursts (GRBs), especially those that present long-lasting X-ray plateau emissions. By solving the field equations, we find that when the rotational speed of the magnetar is approaching the breakup limit, its radius R and moment of inertia I undergo an obvious evolution as the magnetar spins down. Meanwhile, the values of R and I sensitively depend on the adoption of a neutron star (NS) equation of state (EoS) and the NS baryonic mass. With different EoSs and baryonic mass considered, the magnetic dipole radiation luminosity (Ldip) could be variant within one to two orders of magnitude. We thus suggest that when using the X-ray plateau data of GRBs to diagnose the properties of the nascent NSs, EoS and NS mass information should be invoked as simultaneously constrained parameters. On the other hand, due to the evolution of R and I, the temporal behavior of Ldip becomes more complicated. For instance, if the spin-down process is dominated by gravitational wave emission due to the NS asymmetry caused by magnetic field distortion (), the segment Ldip ∝ t0 could be followed by Ldip ∝ t−γ with γ larger than 3. This case could naturally interpret the so-called internal X-ray plateau feature shown in some GRB afterglows, which means the sharp decay following the plateau unnecessarily corresponds to the collapse of the NS. This may explain why some internal X-ray plateaus are followed by late-time central engine activity, manifested through flares and second shallow plateaus. [ABSTRACT FROM AUTHOR]

This investigation aimed to examine the development mechanism of Cu–Ni–Sn compounds and analyze the mechanical properties of mixed solder (MS) joints. Results show that an intermetallic compound (IMC) layer was formed in an SAC305 solder joint prepared herein comprising (Ni, Cu) 3 Sn 4 and (Cu, Ni) 6 Sn 5 phases following the reflow process. The morphology of the (Cu, Ni) 6 Sn 5 grains was identified to be dodecahedral. Meanwhile, the IMC layer of the prepared MS joints contained only the (Cu, Ni) 6 Sn 5 phase, which exhibited a hexagonal prism morphology. The lattice characteristics of Cu 6 Sn 5 changed after Ni dissolution, forming (Cu, Ni) 6 Sn 5 crystals with an X-shaped morphology in the MS joints that exhibited a high Cu content during the aging process. After reflow, the MS joints exhibited slightly higher shear strength than the SAC305 solder joint. After aging at 165 °C for 1000 h, the shear strength of the SAC305 solder joint reduced by 21.72% compared to its value after reflow owing to the annexation of Sn grains. However, the number of Sn grains in the MS joints did not considerably decrease after aging. Further, the grain boundaries of β-Sn and (Cu, Ni) 6 Sn 5 particles contributed to the strengthening of the MS joints. The shear strength of the MS joints decreased by 11.06%–18.35% after aging. • The growth mechanism of Cu–Ni–Sn compounds at Sn–Ag–Cu/Ni solder joints was studied. • The (Cu,Ni) 6 Sn 5 grain morphology of the IMC layer of SAC305 is dodecahedral. • The lattice parameters of Cu 6 Sn 5 changed after Ni dissolution. • X-shaped (Cu,Ni) 6 Sn 5 was formed inside mixed solder joints during aging. • (Cu,Ni) 6 Sn 5 and grain boundaries were strengthened the mixed solder joint. [ABSTRACT FROM AUTHOR]

[Display omitted] • An ultraviolet irradiation in vacuum technique enhancing flashover voltage of SIR. • Illustrate the influence of UVIV on the chain structure of SIR. • Establish a relation between crosslinking of SIR and surface trap parameters. • Explain the effects of surface traps on surface charging and flashover. • Clarify the UVIV improved flashover mechanisms from microscopic to macroscopic. In surface science, surface flashover, which poses a severe danger to the safe operation of modern silicone rubber (SIR)-based electrical equipment, is a continuous discharge event that happens when an intense electric field is produced along the gas-solid interface. To improve the flashover performance, the ultraviolet irradiation in vacuum (UVIV) technique is proposed to modify the SIR surface and the DC flashover threshold increases approximately 14.8 % after 6 h UVIV treatment. Then, the influence mechanisms of UVIV are investigated from microscopic molecule modification to macroscopic flashover performance: The UVIV generates high-energy photons to break C H and Si C bonds in SIR chains, and atoms, group, side chains, and free radicals in chains recombine through the thermally dynamic, causing SIR chains to crosslink. The crosslink chain structure enhances the deep trap energy around the Si O Si bond and introduces large amounts of deep traps. The increment in surface deep trap energy and density captures electrons. It establishes a high electrostatic near the cathode barrier that impedes subsequent electron injection, causing surface charge density decreases far away from the cathode. The reduced surface charges restrict the collision ionization in gas, finally increasing the DC surface flashover voltage through UVIV treatment. [ABSTRACT FROM AUTHOR]

Epoxy nanocomposites with excellent mechanical, thermal and dielectric properties have potential applications in electrical and power electronic devices. However, due to the complex structure of the interfacial region in nanocomposites, molecular dynamic characteristics and how they relate to macro-dielectric performances still needs to be investigated. In this study, several kinds of epoxy nanocomposites were prepared. Segmental dynamics and charge migration parameters are characterised by a dielectric spectroscopy using the Havriliak–Negami equation. The DC breakdown strength of EP/TiO 2 nanocomposites was tested for temperature values between 403 and 433 K, and the influence of segmental dynamic characteristics on DC breakdown was discussed. The results indicate that EP/TiO 2 nanocomposites with optimised filler content (0.5 wt%) have lower values of dielectric relaxation strength, characteristic relaxation time and thermal expansion coefficients than other samples and that segment dynamics and charge transport processes are suppressed by nanoparticle incorporation. The DC breakdown strength of EP/TiO 2 nanocomposites with filler content initially increases and then decreases at a certain temperature, while it significantly decreases with temperature. Correlation analysis indicates that DC breakdown above the glass transition temperature is dominated by segmental dynamics rather than carrier transport. Owing to the tight bond between the nanoparticle and the epoxy matrix, segmental dynamics are impeded when the proper contents of nanoparticles is incorporated, resulting in a decrease in the free-volume fraction and an increase in DC breakdown strength. However, when the temperature rises, the free volume in the intersection of segments expands due to thermal stimulation and free electrons gain sufficient energy in the free length to trigger DC breakdown, hence DC breakdown strength decreases with temperature. [Display omitted] • Characterize the segmental dynamics of EP/TiO 2 nanocomposites. • Improve DC breakdown strength by incorporating 0.5 wt% TiO 2 nanoparticles. • Establish a relationship among breakdown strength, free volume, and chain dynamics. • Discover DC breakdown strength of EP/TiO 2 above T g is governed by segmental dynamics. [ABSTRACT FROM AUTHOR]

To determine the effects of minerals inside char particles and bed materials, the process and mechanism of char combustion in a fluidized bed were studied using a Micro Fluidized Bed Reactor Analyzer. A demineralization procedure using HCl and HF was employed to remove the minerals from pyrolyzed char samples. Raman spectroscopy was used to study the carbon structure of the remaining solid char after demineralization at 500 °C, 600 °C, 700 °C and 800 °C. From the regular changes in band area ratio and full width at half maximum, it can be concluded that as pyrolysis temperature increases, the carbon structure becomes highly ordered, the plane lattice size gradually increases, and the reaction activity decreases from 0.245 s−1 to 0.138 s−1.Furthermore, minerals both within the char particle and in the external bed had marked catalytic activity on char combustion, and their combined catalysis was most notable. CaO and Fe 2 O 3 were the dominant active minerals components contributing to catalytic combustion of char in this study. The catalytic action of CaO was stronger than that of Fe 2 O 3. The activation energy of char combustion ranged from 57.70 kJ/mol to 91.53 kJ/mol, and it significantly decreased in the presence of the bed materials. • The contribution of the minerals in the char and the external material bed to the combustion of the char was studied. • The catalysis of oil shale ash in the external material bed is sometimes greater than the pyrolysis temperature. • CaO and Fe 2 O 3 have obvious catalytic activity. • CaO shows catalytic activity at both low and high temperature, whereas Fe 2 O 3 had strong activity only at low temperature. • The change of ordered carbon structure has a negative effect on the reaction rate of char combustion. • The catalytic mechanism of combustion is concluded. [ABSTRACT FROM AUTHOR]

We investigated the differences in serum brain-derived neurotrophic factor (BDNF) and glial cell line–derived neurotrophic factor (GDNF) levels and clinical symptoms with first-episode depression at different ages. Ninety patients (15–60 years old) diagnosed with first-episode depression were enrolled as the study group, and they were divided into early-onset, adult and late-onset groups. The age-matched control groups were healthy volunteers. Serum BDNF and GDNF concentrations were determined by enzyme-linked immunosorbent assay (ELISA). GraphPad Prism 9 was used for t tests, one-way ANOVAs, chi-square tests, and correlation analyses. p < 0.05 indicated significant differences. Serum BDNF and GDNF levels were lower in the whole study group and the three subgroups than in the healthy groups. Illness severity, anxiety and education were higher in the early-onset than late-onset patients. Serum BDNF levels were lower in the adult than late-onset patients. Serum BDNF levels were negatively correlated with patient CGI-SI scores. After the LSD test for multiple comparisons, the results were also significant. Low serum BDNF and GDNF levels may be involved in the pathophysiology of first-episode depression, and there were differences in serum BDNF levels at different ages, verifying that serum BDNF and GDNF could serve as potential biomarkers of depression. Depression is often conceptualised as a systemic illness with different biological mechanisms, but satisfactory explanations have not been provided thus far. The aim of our study was to investigate differences in serum BDNF and GDNF levels and their relationships with clinical symptoms in patients with first-episode depression at different ages. The potential of the neurotrophic factor hypothesis to advance the diagnosis and treatment of depression will be a very exciting new strategy for future research. [ABSTRACT FROM AUTHOR]

Aims Human skin is the first barrier against pathogens and environmental hazards and the highest contact frequency occurs with the hands. Environmental and personal metabolic factors may affect skin microbes. This study was conducted to clarify the diversity in the skin microbial community that was mainly due to individual skin metabolites rather than lifestyle and environmental factors. Methods and Results Skin microbiota samples were collected from 11 volunteers who met similar lifestyle inclusion criteria. The V3-V4 region of the 16S rRNA gene was amplified. After library construction and sequencing, we compared the composition and diversity of the hand skin microbiota in different sexes and BMI groups with bioinformation analysis. The whole sequence data were annotated as 42 phyla, 538 families, and 1215 genera. Four dominant phyla accounted for 97% of the total including Actinobacteriota (50.18%), Firmicutes (23.85%), Proteobacteria (21.64%) and Bacteroidota (2.05%). The genera that were detected in all subjects with high relative abundance were Cutibacterium, Staphylococcus, Corynebacterium, Streptococcus, Lawsonella, Enhydrobacter, Escherichia-Shigella, Asaia and Micrococcus. Conclusions The diversity and richness of the microbiota of male hand skin in our study was higher than that of females. Interestingly, Cutibacterium, Staphylococcus , and Corynebacterium might serve as important skin microbiota to distinguish sexes. [ABSTRACT FROM AUTHOR]

• Elastic analogues of the Su–Schrieffer–Heeger model and their realization. • Alternating coupling or damping can lead to topological phase transition. • Experimental demonstration of coupling-induced elastic topological edge states. • Experimental demonstration of damping-induced elastic topological edge states. Topological edge states, identified by topological invariants, have been widely investigated in classical wave systems over the past decades due to their intriguing features such as robustness against defects. Most previous studies in this field have so far focused on their Hermitian Hamiltonians characterized by real-valued eigenfrequencies and orthogonal eigenvectors, while the intrinsically lossy nature of classical wave systems has inspired explorations towards their non-Hermitian counterparts for more realistic experimental investigations and practical applications. Here, we present and experimentally demonstrate a type of elastic metamaterials that can be described by the Su–Schrieffer–Heeger (SSH) model to realize topological edge states in elastic wave system under Hermitian or non-Hermitian modulation. The elastic metamaterials are one-dimensional tight-binding chains consisting of square plates (corresponding to mass points) connected by thin beams (corresponding to rigid bonds). For the hypothetically Hermitian case, alternating hopping strengths contribute to dimerization which gives rise to topologically non-trivial and trivial band gaps as well as the associated topological edge states. For the non-Hermitian case, when uneven absorptive dampings are applied to the double-sized unit cell, topological edge states can still be obtained even though the hopping strengths are identical. These results extend the topological physics in elastic wave systems beyond the conventional Hermiticity assumption and could offer greater possibilities for related elastic functional devices. [ABSTRACT FROM AUTHOR]

Many macrocyclic compounds are attractive drug‐like molecules or intermediates due to their special properties. However, the bulk synthesis of such compounds are hindered by the necessity of using diluted solutions, in order to prevent intermolecular reactions that yields oligomer impurities, thereby resulting in a low production efficiency. Such challenge can be adequately addressed by using continuous reactors, allowing improved efficiency with smaller space footprints. In this work, we proposed a novel continuous process for the synthesis of a macrocyclic sulfite of tetraethylene glycol (PEG4‐MCSi), which is a precursor to a very useful building block, PEG4‐macrocyclic sulfate (PEG4‐MCS). The basic reaction parameters, including stoichiometry and temperature, were first confirmed with small batch reactions, and the effectiveness of coiled reactors and continuous stirred tank reactors (CSTRs) were compared. Cascaded CSTRs were proven to be suitable, and the reaction parameters were subject to further optimization to give a robust continuous process. The process was then tested with 4 parallel runs for up to 64 h. Finally, the merits and demerits of batch and continuous reactions were also compared, demonstrating the suitability of latter in the bulk production of macrocyclic PEG‐MCSi compounds. [ABSTRACT FROM AUTHOR]

Strong gravitational lensing effect is a powerful tool to probe cosmological models and gravity theories. Recently, the time-delay cosmography from strong lensing and the stellar kinematics of the deflector, which encode the Hubble constant and the post-Newtonian parameter via two distance ratios reflecting the lensing mass and dynamical mass, respectively, have been proposed to investigate these two parameters simultaneously. Among strong-lensing systems with different sources, strongly lensed fast radio bursts (FRBs) have been proposed as precision probes of the universe since the time-delay ∼ 10 d between images could be measured extremely precisely because of their short duration of a few milliseconds. In this work, we investigate the ability of strongly lensed FRBs on simultaneously estimating these two parameters via simulations. Take the expected FRB detection rate of upcoming facilities and lensing probability into consideration, it is likely to accumulate 10 lensed FRBs in several years and we find that H 0 could be determined to an |$\sim 1.5{{\,\rm per\,cent}}$| precision and γPPN could be constrained to an |$\sim 8.7{{\,\rm per\,cent}}$| precision simultaneously from them. These simultaneous estimations will be helpful for properly reflecting the possible correlation between these two fundamental parameters. [ABSTRACT FROM AUTHOR]

To improve the security, robustness and imperceptibility of watermark scheme, a novel watermark scheme is devised by fusing multiple techniques, including DWT-SVD, Speed-Up Robust Feature (SURF), Random Sample Consensus (RANSAC) algorithm and improved Artificial Bee Colony algorithm named as IABC. To solve the false positive problem in various SVD-based watermark schemes, DWT is employed on the host image and then block wise singular components (maximum) are used for watermark's principal component insertion. On the one hand, IABC algorithm is applied to optimize the scaling factors to balance invisibility and robustness and on the other hand to improve the convergence speed. Moreover, SURF and RANSAC algorithm are used to correct probable geometrical distortion to maintain watermark synchronization. Experimental outcomes demonstrated that compared with the related existing schemes, this scheme exhibits an overall superior performance in the aspects of security, imperceptibility and robustness. [ABSTRACT FROM AUTHOR]

Millilensing of gamma-ray bursts (GRBs) is expected to manifest as multiple emission episodes in a single triggered GRB with similar light-curve patterns and similar spectrum properties. Identifying such lensed GRBs could help improve constraints on the abundance of compact dark matter. Here we present a systemic search for millilensing among 3000 GRBs observed by the Fermi GBM up to 2021 April. Eventually we find four interesting candidates by performing an autocorrelation test, hardness test, and time-integrated/resolved spectrum test. GRB 081126A and GRB 090717A are ranked as the first-class candidates based on their excellent performance in both temporal and spectrum analysis. GRB 081122A and GRB 110517B are ranked as the second-class candidates (suspected candidates), mainly because their two emission episodes show clear deviations in part of the time-resolved spectrum or in the time-integrated spectrum. Considering a point-mass model for the gravitational lens, our results suggest that the density parameter of lens objects with mass M L ∼ 106 M ⊙ is larger than 1.5 Ă— 10âˆ'3. [ABSTRACT FROM AUTHOR]

The transition-edge sensor (TES) as a type of low-temperature superconducting detector offers superior sensitivity due to its low thermal noise. In this work, we present a prototype TES bolometer designed for cosmic microwave background (CMB) polarization measurements. This TES is made of aluminum doped with a low concentration of manganese (2000 ppm by atomic percentage), and is deposited on the SiNx membrane which connects to the silicon substrate via narrow legs. In order to calculate its electrothermal parameters we have performed dark characterizations, which include measuring voltage-current (IV) curve at different bath temperatures, square-wave time response at various bias voltages, and noise level. This TES bolometer shows a noise equivalent power (NEP) of about 5 × 10 - 17 W/ Hz , which meets the requirement of CMB observation. However, its saturation power is smaller and time constant is larger than what are expected. We have analyzed the reasons and will make corresponding improvements in our future work. [ABSTRACT FROM AUTHOR]

Precision control of multiple robotic fish visual navigation in complex underwater environments has long been a challenging issue in the field of underwater robotics. To address this problem, this paper proposes a multi-robot fish obstacle traversal technique based on the combination of cross-modal variational autoencoder (CM-VAE) and imitation learning. Firstly, the overall framework of the robotic fish control system is introduced, where the first-person view of the robotic fish is encoded into a low-dimensional latent space using CM-VAE, and then different latent features in the space are mapped to the velocity commands of the robotic fish through imitation learning. Finally, to validate the effectiveness of the proposed method, experiments are conducted on linear, S-shaped, and circular gate frame trajectories with both single and multiple robotic fish. Analysis reveals that the visual navigation method proposed in this paper can stably traverse various types of gate frame trajectories. Compared to end-to-end learning and purely unsupervised image reconstruction, the proposed control strategy demonstrates superior performance, offering a new solution for the intelligent navigation of robotic fish in complex environments. [ABSTRACT FROM AUTHOR]

Summary: Thermoelectric generator (TEG) can utilize intermittent temperature fluctuations of the aircraft's fuselage to provide power for wireless structural health monitoring systems. In this article, a novel phase change material (PCM)‐TEG system of integrating PCM with TEG for improving the output performance was reported. The proposed system was almost adiabatic with the external environment, which effectively avoided heat exchange with the internal environment of the aircraft. High‐performance paraffin/expanded graphite (EG) composite PCM was fabricated by a simple melting‐adsorption approach. Because of the porous structure and high thermal conductivity of EG, significant enhancement in the thermal conductivity of the composite was observed, while there was little decrease in the latent heat capacity. A variety of typical experimental conditions were designed by aero‐thermal calculation method that based on the actual service environment of aircraft. The output performance of the TEG and thermal transfer properties of the composite were investigated systematically, which showed that the existence of PCM increased the temperature difference between the two sides of the TEG and effectively promoted its energy conversion potential. Finally, the performance for the PCM‐TEG system was also compared under different experimental conditions. The study provides a solution for obtaining electrical power source, which is highly desired in wireless structural health monitoring systems. [ABSTRACT FROM AUTHOR]

Electrochemical hydrogen compressors (EHC) are favored for their quiet operation, efficiency, and low energy consumption in hydrogen purification and compression. A key challenge in EHC development is developing high-performance proton exchange membranes (PEMs) that manages water effectively. Herein, we've crafted a series of comb-shaped N-alkylation sulfonated poly(oxindole biphenylene) (SPOBP-C n -x) (n = 0, 6, 10, 16) PEMs with varying side chain lengths. These PEMs feature distinct designs with sulfonic acid groups and hydrophobic chains attached to different locations of the indigo groups, which not only enhance ion conductivity by inducing the formation of microphase separated morphology but also retain their water absorption behaviors. The SPOBP-C 10 -10 membrane displayed the highest proton conductivity of 209.7 mS/cm (60 °C) and retain water uptake of 148.8 wt%. All the membranes exhibited low hydrogen back-diffusion permeability. Moreover, SPOBP-C n -10 membranes outperformed Nafion 112 in EHC cells, with SPOBP-C 10 -10 exhibiting a notably low 0.1 V operating voltage at 1 A/cm2 (RH = 100%). EHC device durability tests for SPOBP-C 10 -10 at 200 mA/cm2 and 60 °C demonstrated a stability for over 440 h with very slight variations in voltage. These results indicate that the comb-shaped structure with alkyl side chains and sulfonic acid groups adjacent to the backbone is an effective strategy for achieving satisfactory high conductivity, water uptake and energy efficiency of PEMs for use in EHC. [Display omitted] • A series of ether-free backbone comb-shaped SPOBP-C n -x were designed and synthesized. • Comb-shaped SPOBP-C 10 -10 membrane exhibited an optimized proton conductivity of 209.7 mS/cm at 60 °C. • EHC initial performance of SPOBP-C 10 -10 achieved an operating voltage of 0.1 V at 1 A/cm2. [ABSTRACT FROM AUTHOR]

Thermal protection materials with excellent thermal insulation properties and high reliability are crucial for aerospace vehicle. Mullite fiber insulation tiles coated with MoSi 2 -borosilicate glass (MFIT@MoSi 2) were prepared by a simple slurry method. Results shown that the surface temperature rapidly reached 1043.1 °C under the heat flux of 450 kW/m2, while the cold-surface remained at room temperature. The adjusting effects of MoSi 2 -based coating on the thermal response and transfer properties of MFIT were investigated systematically. Compared with MFIT, the surface and internal temperatures of MFIT@MoSi 2 were obviously suppressed, due to the existence of MoSi 2 -based coating with high emissivity, which effectively enhanced the thermal radiation of the surfaces. Finally, the structural reliability under coupled environment of heating (q 0 = 450 kW/m2) and random vibration with high magnitude (20–2000 Hz, Grms = 20 g) was also investigated. Destructive cracking and peeling of the coating were not observed, due to the excellent bonding strength between the coating and the substrate. The results provided an important basis for the potential application of insulation tiles with mullite fibers in aerospace vehicles and the design of lightweight thermal protection systems. [ABSTRACT FROM AUTHOR]

Gamma-ray bursts (GRBs) at high redshifts are expected to be gravitationally lensed by objects of different mass scales. Other than a single recent claim, no lensed GRB has been detected so far by using gamma-ray data only. In this paper, we suggest that multiband afterglow data might be an efficient way to search for lensed GRB events. Using the standard afterglow model, we calculate the characteristics of the lensed afterglow lightcurves under the assumption of two popular analytic lens models: the point-mass and singular isothermal sphere models. In particular, when different lensed images cannot be resolved, their signals would be superimposed together with a given time delay. In this case, the X-ray afterglows are likely to contain several X-ray flares of similar width in linear scale and similar spectrum, and the optical afterglow lightcurve will show re-brightening signatures. Since the lightcurves from the image arriving later would be compressed and deformed in the logarithmic timescale, the larger time delay (i.e., the larger mass of the lens), the easier it is to identify the lensing effect. We analyzed the archival data of optical afterglows and found one potential candidate of the lensed GRB (130831A) with time delay ∼500 s; however, observations of this event in gamma-ray and X-ray bands seem not to support the lensing hypothesis. In the future, with the cooperation of the all-sky monitoring gamma-ray detectors and multiband sky survey projects, the method proposed in this paper would be more efficient in searching for strongly lensed GRBs. [ABSTRACT FROM AUTHOR]

Gamma-ray bursts (GRBs) at high redshifts are expected to be gravitationally lensed by objects of different mass scales. Other than a single recent claim, no lensed GRB has been detected so far by using gamma-ray data only. In this paper, we suggest that multiband afterglow data might be an efficient way to search for lensed GRB events. Using the standard afterglow model, we calculate the characteristics of the lensed afterglow lightcurves under the assumption of two popular analytic lens models: the point-mass and singular isothermal sphere models. In particular, when different lensed images cannot be resolved, their signals would be superimposed together with a given time delay. In this case, the X-ray afterglows are likely to contain several X-ray flares of similar width in linear scale and similar spectrum, and the optical afterglow lightcurve will show re-brightening signatures. Since the lightcurves from the image arriving later would be compressed and deformed in the logarithmic timescale, the larger time delay (i.e., the larger mass of the lens), the easier it is to identify the lensing effect. We analyzed the archival data of optical afterglows and found one potential candidate of the lensed GRB (130831A) with time delay ∼500 s; however, observations of this event in gamma-ray and X-ray bands seem not to support the lensing hypothesis. In the future, with the cooperation of the all-sky monitoring gamma-ray detectors and multiband sky survey projects, the method proposed in this paper would be more efficient in searching for strongly lensed GRBs. [ABSTRACT FROM AUTHOR]

Background: Alcohol consumption and cardiovascular disease (CVD) have a complex relation.Objectives: We examined the associations between alcohol consumption, fasting plasma proteins, and CVD risk.Methods: We performed cross-sectional association analyses of alcohol consumption with 71 CVD-related plasma proteins, and also performed prospective association analyses of alcohol consumption and protein concentrations with 3 CVD risk factors (obesity, hypertension, and diabetes) in 6745 Framingham Heart Study (FHS) participants (mean age 49 y; 53% women).Results: A unit increase in log10 transformed alcohol consumption (g/d) was associated with an increased risk of hypertension (HR = 1.14; 95% CI: 1.04, 1.26; P = 0.007), and decreased risks of obesity (HR = 0.80; 95% CI: 0.71, 0.91; P = 4.6 × 10-4) and diabetes (HR: 0.68; 95% CI: 0.58, 0.80; P = 5.1 × 10-6) in a median of 13-y (interquartile = 7, 14) of follow-up. We identified 43 alcohol-associated proteins in a discovery sample (n = 4348, false discovery rate <0.05) and 20 of them were significant (P <0.05/43) in an independent validation sample (n = 2397). Eighteen of the 20 proteins were inversely associated with alcohol consumption. Four of the 20 proteins demonstrated 3-way associations, as expected, with alcohol consumption and CVD risk factors. For example, a greater concentration of APOA1 was associated with higher alcohol consumption (P = 1.2 × 10-65), and it was also associated with a lower risk of diabetes (P = 8.5 × 10-6). However, several others showed unexpected 3-way associations.Conclusions: We identified 20 alcohol-associated proteins in 6745 FHS samples. These alcohol-associated proteins demonstrated complex relations with the 3 CVD risk factors. Future studies with integration of more proteomic markers and larger sample size are warranted to unravel the complex relation between alcohol consumption and CVD risk. [ABSTRACT FROM AUTHOR]

The detection of a secular post-merger gravitational wave (GW) signal in a binary neutron star (BNS) merger serves as strong evidence for the formation of a long-lived post-merger neutron star (NS), which can help constrain the maximum mass of NSs and differentiate NS equations of state. We specifically focus on the detection of GW emissions from rigidly rotating NSs formed through BNS mergers, using several kilohertz GW detectors that have been designed. We simulate the BNS mergers within the detecting limit of LIGO-Virgo-KARGA O4 and attempt to find out on what fraction the simulated sources may have a detectable secular post-merger GW signal. For kilohertz detectors designed in the same configuration of LIGO A+, we find that the design with peak sensitivity at approximately 2 kHz is most appropriate for such signals. The fraction of sources that have a detectable secular post-merger GW signal would be approximately |$0.94{\!-\!}11~{{ \rm per\ cent}}$| when the spin-downs of the post-merger rigidly rotating NSs are dominated by GW radiation, while it would be approximately |$0.46{\!-\!}1.6~{{ \rm per\ cent}}$| when the contribution of electromagnetic (EM) radiation to the spin-down processes is non-negligible. We also estimate this fraction based on other well-known proposed kilohertz GW detectors and find that, with advanced design, it can reach approximately |$12{\!-\!}45~{{ \rm per\ cent}}$| for the GW-dominated spin-down case and |$4.7{\!-\!}16~{{\rm per\ cent}}$| when both the GW and EM radiations are considered. [ABSTRACT FROM AUTHOR]

The determination of the low-temperature plasma propagation of SF6/N2 in gas discharge will accelerate the application of SF6/N2 in advanced electrical equipment. This study investigates the positive streamer propagation characteristics of SF6/N2 by establishing a plasma discharge model and discusses the effects of SF6 ratio on the electron density, electric field, chemical reaction rates, ion concentrations, and streamer thickness and velocity. As the streamer propagates, the shapes of the electron density and electric field become "narrower and taller." Moreover, the ionization and attachment reaction rates increase, and the streamer thickness and velocity decrease with increasing SF6 mixing ratio and propagation time. As the SF6 ratio increases, the electric field distortion degree and particle mobility near the high-voltage electrode decrease due to the increase in the ionization and attachment rates. Consequently, the streamer velocity remains nearly unchanged, but the streamer thickness obviously decreases in the corona discharge process. In the streamer propagation process, the decrease in the streamer thickness and velocity with increasing SF6 ratio is attributed to the reduction in the electric field distortion and particle mobility, which stems from the increase in the DC breakdown voltage with the SF6 mixing ratio. The study results clarify the influence mechanisms of the SF6 mixing ratio on the particles' spatiotemporal evolution during streamer propagation. [ABSTRACT FROM AUTHOR]

Plant organ primordia develop successively at the shoot apical meristem (SAM). In Arabidopsis, primordia formed early in development differentiate into vegetative leaves, whereas those formed later generate inflorescence branches and flowers. TERMINAL FLOWER 1 (TFL1), a negative regulator of transcription, acts in the SAM to delay flowering and to maintain inflorescence meristem indeterminacy. We used confocal microscopy, time-resolved transcript profiling and reverse genetics to elucidate this dual role of TFL1. We found that TFL1 accumulates dynamically in the SAM reflecting its dual function. Moreover, TFL1 represses two major sets of genes. One set includes genes that promote flowering, expression of which increases earlier in tfl1 mutants. The other set is spatially misexpressed in tfll inflorescence meristems. The misexpression of these two gene sets in tfl1 mutants depends upon FD transcription factor, with which TFL1 interacts. Furthermore, the MADS-box gene SEPALLATA 4, which is upregulated in tfl1, contributes both to the floral transition and shoot determinacy defects of tfl1 mutants. Thus, we delineate the dual function of TFL1 in shoot development in terms of its dynamic spatial distribution and different modes of gene repression. [ABSTRACT FROM AUTHOR]

The attainment of accurate motion control for robotic fish inside intricate underwater environments continues to be a substantial obstacle within the realm of underwater robotics. This paper presents a proposed algorithm for trajectory tracking and obstacle avoidance planning in robotic fish, utilizing nonlinear model predictive control (NMPC). This methodology facilitates the implementation of optimization-based control in real-time, utilizing the present state and environmental data to effectively regulate the movements of the robotic fish with a high degree of agility. To begin with, a dynamic model of the robotic fish, incorporating accelerations, is formulated inside the framework of the world coordinate system. The last step involves providing a detailed explanation of the NMPC algorithm and developing obstacle avoidance and objective functions for the fish in water. This will enable the design of an NMPC controller that incorporates control restrictions. In order to assess the efficacy of the proposed approach, a comparative analysis is conducted between the NMPC algorithm and the pure pursuit (PP) algorithm in terms of trajectory tracking. This comparison serves to affirm the accuracy of the NMPC algorithm in effectively tracking trajectories. Moreover, a comparative analysis between the NMPC algorithm and the dynamic window approach (DWA) method in the context of obstacle avoidance planning highlights the superior resilience of the NMPC algorithm in this domain. The proposed strategy, which utilizes NMPC, demonstrates a viable alternative for achieving precise trajectory tracking and efficient obstacle avoidance planning in the context of robotic fish motion control within intricate surroundings. This method exhibits considerable potential for practical implementation and future application. [ABSTRACT FROM AUTHOR]

The path planning problem has gained more attention due to the gradual popularization of mobile robots. The utilization of reinforcement learning techniques facilitates the ability of mobile robots to successfully navigate through an environment containing obstacles and effectively plan their path. This is achieved by the robots' interaction with the environment, even in situations when the environment is unfamiliar. Consequently, we provide a refined deep reinforcement learning algorithm that builds upon the soft actor-critic (SAC) algorithm, incorporating the concept of maximum entropy for the purpose of path planning. The objective of this strategy is to mitigate the constraints inherent in conventional reinforcement learning, enhance the efficacy of the learning process, and accommodate intricate situations. In the context of reinforcement learning, two significant issues arise: inadequate incentives and inefficient sample use during the training phase. To address these challenges, the hindsight experience replay (HER) mechanism has been presented as a potential solution. The HER mechanism aims to enhance algorithm performance by effectively reusing past experiences. Through the utilization of simulation studies, it can be demonstrated that the enhanced algorithm exhibits superior performance in comparison with the pre-existing method. [ABSTRACT FROM AUTHOR]

Biological agents known as anti-tumor necrosis factor (TNF) drugs are frequently utilized in the treatment of inflammatory bowel disease (IBD). In this study, we analyzed the shared processes of pyroptosis in Ulcerative colitis (UC) and Crohn's disease (CD), as well as explored the correlation between the burden of pyroptosis and the results of anti-TNF treatment based on bioinformatics analyses. We identified CAPS1, CASP5, GSDMD, AIM2, and NLRP3 as the hub genes, with AIM2 being the most effective indicator for predicting the response to anti-TNF therapy. We also noticed that non-responders received anti-TNF therapy exhibited elevated AIM2 protein expression. Subsequently, we conducted a cluster analysis based on AIM2-inflammasome-related genes and discovered that patients with a higher burden of AIM2 inflammasome displayed stronger immune function and a poor response to anti-TNF therapy. Overall, our study elucidates the pathway of pyroptosis in IBD and reveals AIM2 expression level as a potential biomarker for predicting the effectiveness of anti-TNF therapy. [ABSTRACT FROM AUTHOR]

Spectral lag of the low-energy photons with respect to the high-energy ones is a common astrophysical phenomenon (such as gamma-ray bursts and the Crab Pulsar) and may serve as a key probe to the underlying radiation mechanism. However, spectral lag in keV range of the magnetar bursts has not been systematically studied yet. In this work, we perform a detailed spectral lag analysis with the Li et al.'s Cross-Correlation Function (Li-CCF) method for SGR J1935+2154 bursts observed by Insight - Hard X-ray Modulation Telescope (HXMT), Gravitational Wave High-energy Electromagnetic Counterpart All-sky Monitor (GECAM), and Fermi /Gamma-ray Burst Monitor (GBM) from 2014 July to 2022 January. We discover that the spectral lags of about 61 per cent (non-zero significance >1σ) bursts from SGR J1935+2154 are linearly dependent on the photon energy (E) with t lag(E) = α(E /keV) + C , which may be explained by a linear change of the temperature of the blackbody-emitting plasma with time. The distribution of the slope (α) approximately follows a Gaussian function with mean and standard deviation of 0.02 ms keV−1 (i.e. high-energy photons arrive earlier) and 0.02 ms keV−1, respectively. We also find that the distribution can be well fitted with three Gaussians with mean values of ∼−10.009, 0.013, and 0.039 ms keV−1, which may correspond to different origins of the bursts. These spectral lag features may have important implications on the magnetar bursts. [ABSTRACT FROM AUTHOR]

A realistic and visible dynamic simulation platform can significantly facilitate research on underwater robots. This paper uses the Unreal Engine to generate a scene that resembles real ocean environments, before building a visual dynamic simulation platform in conjunction with the Air-Sim system. On this basis, the trajectory tracking of a biomimetic robotic fish is simulated and assessed. More specifically, we propose a particle swarm optimization algorithm-based control strategy to optimize the discrete linear quadratic regulator controller for the trajectory tracking problem, as well as tracking and controlling discrete trajectories with misaligned time series through introducing a dynamic time warping algorithm. Simulation analyses of the biomimetic robotic fish following a straight line, a circular curve without mutation, and a four-leaf clover curve with mutation are carried out. The obtained results verify the feasibility and effectiveness of the proposed control strategy. [ABSTRACT FROM AUTHOR]