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• SIRT1 might be an important target of Ligustrazine to relieve migraine symptoms. • Ligustrazine mitigates neuroinflammation by stabilization of SIRT1 in microglia. • Decline of SIRT1 in M1 microglia induces neuronal oxidative damage. • Ligustrazine participates in the microglial-neuronal crosstalk via Nrf2 signaling. Neuroinflammation with associated oxidative stress aggravates the pathogenesis and progression of migraine. Ligustrazine (LGZ) is a key component from traditional edible-medicinal herb Ligusticum chuanxiong Hort., and has the effects of anti-platelet aggregation, expanding small arteries, improving microcirculation and promoting blood circulation and removing blood stasis in clinic. This study aims to investigate the pharmacological effect and mechanism of LGZ in migraine. A mouse model of migraine was induced by nitroglycerin (NTG), and LPS/IFN-γ stimulated microglial cell model was conducted to investigate neuroinflammation, the paracrine interactions between microglia and neurons were determined by the co-culture system, and the effect of LGZ on stability of SIRT1 protein was measured by cellular thermal shift assay (CETSA). Whilst, the SIRT1 inhibitor EX527 was used alone or co-treatment with LGZ in vitro or in vivo. LGZ significantly attenuated migraine-like behaviors in NTG-induced mice, and ameliorated neuroinflammation and related oxidative damage in brain tissue, but co-treatment with SIRT1 inhibitor EX527 abolished the protective effects of LGZ. Mechanistically, LGZ mitigated neuroinflammation by upregulating SIRT1 expression and subsequently inhibiting the activation of NF-κB pathway in microglia. CETSA indicated that LGZ significantly maintained the stability of SIRT1 protein in microglia. While, in the co-culture system, culture medium from LPS/IFN-γ-treated microglia exacerbated neuronal damage and oxidative stress, which was suppressed by treating LPS/IFN-γ-induced microglia with LGZ, this effect might be related to the activation of Nrf2 signals in neurons. Notably, SIRT1 inhibitor EX527 abrogated the effects of LGZ both in vitro and in vivo. Consequently, SIRT1 might be an important pharmacological target of LGZ, which attenuates migraine associated neuroinflammation and oxidative stress by interfering the crosstalk between microglia and neurons, thereby relieving migraine. [Display omitted] [ABSTRACT FROM AUTHOR]

In the process of service, the coating is vulnerable to ultraviolet radiation, which leads to aging failure. The metakaolin base geopolymer coating studied in this paper has excellent mechanical and anti-corrosion properties through the previous mix ratio study. However, the UV aging resistance of the coating is unknown. In response to this issue, the present study devised UV aging experiments for metakaolin based geopolymer coatings. Employing UV irradiation in conjunction with EIS tests, the aging resistance of the geopolymer coatings was assessed through electrochemical fitting and analyses such as SEM. The study delves into the structural evolution of metakaolin based geopolymer coatings under UV aging conditions. After 500 h of ultraviolet irradiation, the resistance of the geopolymer coating is enhanced, its water diffusion coefficient is reduced, two orders of magnitude increase the resistance of the coating, and the protection performance of the geopolymer coating is enhanced. In the control group, the waterproof performance of epoxy resin decreased significantly, the impedance decreased, and the resistance decreased by three orders of magnitude. SEM results show that the post-curing of the coating under UV irradiation continuously generates NASH gels, and the coating microstructure is dense. The results show that geopolymer has strong aging resistance. • This experiment investigates the mechanism of UV ageing resistance of metakaolin base geopolymer coatings. • Comparison with epoxy resin coatings concludes that the geopolymer coatings have very good UV aging resistance. • The system of evaluating the water resistance and porosity of the coatings by capacitance method based on Fick's law of diffusion is applicable to the geopolymer coatings. • UV irradiation induces a post-curing reaction of the geopolymer coatings. [ABSTRACT FROM AUTHOR]

The digestibility and structural changes of rice starch induced by heat-moisture treatment (HMT) were investigated, and the relationships among the moisture content–starch structure–starch digestibility were revealed. HMT could simultaneously disorder and reassemble the rice starch molecules across multi-scale lengths and convert some fractions of rapidly-digestible starch (RDS) into slowly-digestible starch (SDS) and resistant starch (RS). In particular, the HMT rice starch with less than 30% moisture content showed a higher SDS + RS content (25.0%). During HMT, SDS and RS were preferably formed by the degraded starch molecules with M w between 4 × 10 5 and 4 × 10 6 g/mol, single helices and amylose-lipids complexes that were formed by degraded starch chains with higher thermal stability and crystalline lamellae with greater thicknesses. Thus, our research suggests a potential approach using HMT to control the digestion of starch products with desired digestibility. [ABSTRACT FROM AUTHOR]

Understanding the underlying interactions of nanoparticles (NPs) with cells is crucial to the nanotoxicological research. Evidences suggested lysosomes as a vital target upon the accumulation of internalized NPs, and lysosomal damage and autophagy dysfunction are emerging molecular mechanisms for NPs-elicite d toxicity. Nevertheless, the interaction with lysosomes, ensuing adverse effects and the underlying mechanisms are still largely obscure, especially in NPs-induced vascular toxicity. In this study, silica nanoparticles (SiNPs) were utilized to explore the adverse effects on lysosome in vascular endothelial cells by using in vitro cultured human endothelial cells (HUVECs), and in-depth investigated the mechanisms involved. Consequently, the internalized SiNPs accumulated explicitly in the lysosomes, and caused lysosomal dysfunction, which were prominent on the increased lysosomal membrane permeability, decline in lysosomal quantity, destruction of acidic environment of lysosome, and also disruption of lysosomal enzymes activities, resulting in autophagy flux blockage and autophagy dysfunction. More importantly, mechanistic results revealed the SiNPs-caused lysosomal impairments and resultant autophagy dysfunction could promote oxidative stress, DNA damage and the eventual cell apoptosis activated by ROS/PARP1/AIF signaling pathway. These findings improved the understanding of SiNPs-induced vascular injury, and may provide novel information and warnings for SiNPs applications in the fields of nanomedicine. [Display omitted] • SiNPs targeted endothelial lysosomes, impaired its structure and function. • SiNPs disrupted autophagosome-lysosome fusion, resulting in autophagy dysfunction. • Lysosome-autophagy dysfunction promoted oxidative stress, DNA damage and apoptosis. • Lysosome-autophagy dysfunction contributed to apoptosis by ROS/PARP1/AIF signaling. [ABSTRACT FROM AUTHOR]

Morphological transformation only occurs in polymer blends via changing their components, which can be utilized to form double percolation structures. However, the weight percentage of either polymer in the blend generally ranges from 40 wt% to 60 wt%, which does not favor the construction of a densely conductive path. Herein, a double percolation structure had been successfully constructed in a polylactide-polycaprolactone (PLA/PCL) blend with only 30 wt% PCL by adding silicon dioxide (SiO 2) to the PLA phase. The added SiO 2 effectively strengthens the viscosity and elasticity of the PLA phase, which results in the morphological transformation of the PCL phase from segregated to continuous. In the blend, multi-wall carbon nanotubes (MWCNTs) were selectively distributed in the PCL phase to construct a more efficient conductive network, which brings about an enormous increase in conductivity for the nanocomposites. The electrical conductivity of PLA/PCL nanocomposite increases from 1.19 × 10−14 S/m to 4.57 × 10−4 S/m with the addition of 1.0 wt% MWCNTs and 6.0 wt% SiO 2. The percolation threshold of the MWCNTs in the nanocomposite (0.11 wt%, i.e. 0.06 vol%) is 125% lower than that without SiO 2 (0.28 wt%, i.e. 0.14 vol%). Furthermore, the nanocomposites with SiO 2 were found to exhibit an electromagnetic interference (EMI) of approximately 26 dB with only 3.0 wt% MWCNTs, which means it can block 99.997% of microwaves. This study would provide a critical method to design eco-friendly nanocomposites with ultralow percolate threshold and excellent EMI shielding. The addition of SiO2 can change the viscosity ratio of PLA:PCL, then the morphology inversion occurs. The PCL (30 wt%) phase change from segregated to continue, and the MWCNTs was selectively dispersed in the PCL phase so that the conductive polymer nanocomposites with low percolation threshold and excellent EMI was achieved. [Display omitted] • A low percolation threshold of CPCs with excellent EMI was achieved. • It is first time to use the SiO 2 to alter the morphology and form the conductive network. • The MWCNTS was selectively dispersed in the PCL phase (30 wt%). [ABSTRACT FROM AUTHOR]

Because of their excellent insulation performance and processing properties, polymers are widely used in electrical and electronic applications. However, their further applications are severely constrained by their extremely low intrinsic thermal conductivity. Boron nitride (BN), which has high thermal conductivity and ideal insulation properties, is commonly used as a filler for improving the thermal conductivity of polymers. However, the high chemical inertia of the surface of BN makes it difficult to achieve an interconnection of BN sheets when building a three-dimensional (3D) BN skeleton in a polymer. In this study, urea melt pore preparation (UMPP) was used to fabricate a 3D BN skeleton. Urea was infiltrated into the BN skeleton to minimize the interfacial thermal resistance among the BN flakes and to join BNs. When the volume of a BN is 10 %, the thermal conductivity of the BN/epoxy composites is 3.15 W/(m·K). When the BN volume is 80 %, the thermal conductivity of BN/epoxy can reach 13.65 W/(m·K), which is 6500 % of pure epoxy resin. Additionally, the skeleton exhibits a remarkable mechanical strength capable of supporting weights up to 50,000 times its own, which facilitates easier handling and operation. The electrical resistivity volume of the UMPP composite is as high as that of the pure epoxy, whereas the dielectric loss is lower than that of pure epoxy. This study provides a new method for reducing internal interface thermal resistance of a skeleton formed by thermal conductive fillers with high chemical inertia such as boron nitride. [ABSTRACT FROM AUTHOR]

Abstract Organic light-emitting devices (OLEDs) consisting of a non-doped phosphorescent dye that inserted in an exciplex forming planar structure have been fabricated, and the thickness of ultrathin phosphor layer is optimized to achieve high efficiency. The results showed that OLEDs based on the exciplex interface and a 0.5 nm thick phosphorescent dye have a power efficiency, a current efficiency, and an external quantum efficiency of 37.4 lm/W, 40.5 cd/A, and 14.3%, respectively, which are almost two-folds higher than those with non-exciplex interface devices. Meanwhile, the efficiency roll-off is significantly suppressed. These improved device performances are attributed to the elimination of triplet energy leakage from exciplexes to constituting molecules, efficient energy up conversion of triplet exciplexes and complete host-guest Förster energy transfer. These results will provide an easily-fabricated and time-saving approach for high-performance OLEDs. Graphical abstract Image 1 Highlights • Efficiency enhanced PHOLEDs with an exciplex forming planar structure are realized. • PHOLEDs consist of phosphorescent dye slightly doped in electron D: A mixed co-hosts. • Exciplex based devices have low efficiency roll-off from host-guest energy transfer. [ABSTRACT FROM AUTHOR]

[Display omitted] • Quick start-up of Anammox process was achieved within 21 days. • The SNAD operates consistently and efficiently with an average DO of 0.051 mg/L. • The accumulation and dominance of AnAOB occur in the inner layers of biofilms. • The inhibition of NOB was effectively achieved in a continuous hypoxic environment. • The intermittent aeration operation mode was investigated. In this study, a SNAD-SBBR process was implemented to achieve ammonia removal and carbon reduction of mature landfill leachate under extremely low dissolved oxygen conditions (0.051 mg/L) for a continuous operation of 266 days. The process demonstrated excellent removal performance, with ammonia nitrogen removal efficiency reaching 100 %, total nitrogen removal efficiency reaching 87.56 %, and an average removal rate of 0.180 kg/(m3·d). The recalcitrant organic compound removal efficiency reached 34.96 %. Nitrogen mass balance analysis revealed that the Anammox process contributed to approximately 98.1 % of the nitrogen removal. Candidatus Kuenenia achieved a relative abundance of 1.49 % in the inner layer of the carrier. In the SNAD-SBBR system, the extremely low DO environment created by the highly efficient partial nitrification stage enabled the coexistence of AnAOB, denitrifying bacteria, and Nitrosomonas , synergistically achieving ammonia removal and carbon reduction. Overall, the SNAD-SBBR process exhibits low-cost and high-efficiency characteristics, holding tremendous potential for landfill leachate treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel IBBR system was developed to treat landfill leachate and operated 343 days. • PN/A process was quickly started through inoculated activated sludge within 86 days. • The thicker biofilm enables the enrichment of denitrifying bacteria in BAF. • High TNRE of 93.3 % and NRR of 1.13 kg N/(m3·d) was achieved. • A high abundance of AnAOB (Ca. Kuenenia) was enriched, accounting for 1.7%. Considering the challenges associated with nitrogen removal from mature landfill leachate, a novel combined continuous-flow process integrating denitrification and partial nitrification-Anammox (PN/A) was developed using an internal circulation (IC) system and a biological aerated filter (BAF) biofilm reactor (IBBR). In this study, IBBR successfully operated for 343 days, and when influent N H 4 + -N concentration of mature landfill leachate reached 1258.1 mg/L, an impressive total nitrogen removal efficiency (TNRE) of 93.3 % was achieved, along with a nitrogen removal rate (NRR) of 1.13 kg N/(m3·d). The analysis of the microbial community revealed that Candidatus Kuenenia , the dominant genus responsible for anammox, accounted for 1.7 % (day 265). Additionally, Nitrosomonas , Thauera and Truepera were identified as key contributors to the efficient removal of nitrogen from mature landfill. As a novel nitrogen removal strategy, the practical application of the IBBR system offers novel perspectives on addressing mature landfill leachate. [ABSTRACT FROM AUTHOR]

• This work shows a first attempt to research SMC issue for continuous-time nonlinear NCSs. • An ETM-based observer model is designed for the systems, which can not only obtain state information but also reduce the transmission rate of network bandwidth resources effectively. This work concentrates on addressing the sliding mode control problem of continuous-time nonlinear networked control systems. Considering the state information may not be utterly available in practice, a state observer model is designed to estimate the state information. Meanwhile, a type of discrete-time event-triggered mechanism is utilized to filter the sampled signal for reducing the occupation of network bandwidths and the transmission rate of resources. In addition, a random variable obeying the Bernoulli distribution is adopted to describe the phenomenon of uncertainties randomly occurring in the measurement. With the aid of the Lyapunov stability and sliding mode control theory, some sufficient criteria are given to both guarantee the mean-square asymptotic stability of the overall closed-loop system with an extended dissipative performance, and the reachability of predefined sliding surface. Whereafter, the event-triggered weighting matrix, and gains of sliding mode controller and with observer are obtained by solving the matrix convex optimization problem. Finally, the feasibility of the presented scheme is demonstrated through two illustrative examples. [ABSTRACT FROM AUTHOR]

• Rice starch-unsaturated fatty acid complex (R-UFA) was formed under HPH. • Ordered structure was induced as the complex registered into a V-type crystalline. • Longer chain length of unsaturated fatty acid led to lower digestibility of R-UFA. • Cis monounsaturated fatty acid led to lower digestibility of R-UFA. • Relations between structure and in-vitro digestibility of R-UFA were established. This study emphasized on structural alteration of rice starch-unsaturated fatty acid complexes by adding trans-2-dodecaenoic acid (t12), trans-oleic acid (t18), cis-oleic acid (c18) and linoleic acid (loa) with different concentration under high-pressure homogenization treatment, and further illustrated the underlying mechanism of modulating digestibility. Results showed that the complex primarily presented as V6 or type IIa polymorph; complex index, content of ordered structure and thermal stability appeared to be positively correlated to the concentration of unsaturated fatty acids. t12 was too mobile to form single helix, leading to the formation of loose matrix; t18 fitted better within the cavity of starch than c18, and formed structural domain with higher compactness and thermal stability; Rloa had lower complex index but higher degree of short-range order, and tended to form alternating amorphous and crystalline structure. The digestibility was higher in the order of Rloa, Rt18, Rc18 and Rt12. [ABSTRACT FROM AUTHOR]

• A CW laser deposition and pulsed laser finishing hybrid technique was proposed to repairing the 30CrMnSiNi2A steel. • The micro-hardness and the wear resistance of the repaired zone can be improved greatly compared with the matrix. • The surface finish and the grain refinement can be obviously improved. The 30CrMnSiNi2A ultra-strength steel features excellent comprehensive mechanical properties and has been widely used to manufacture structural parts such as the aircraft landing gear, the wing girder, the missile engine shell, etc. However, wear and defects are produced on the surface of these parts in the course of their long-term service. In this paper, a continuous-wave laser deposition and pulsed laser finishing hybrid technique was proposed to repair 30CrMnSiNi2A ultra-high strength steel. The microstructure and mechanical properties of 30CrMnSi2A alloy matrix, laser repairing and laser finishing parts were compared. Laser finishing parameters were optimized to further improve the surface properties of the repaired parts. The effect of different process parameters on the surface morphology, microstructures, micro-hardness and wear resistance was explored. The results revealed that the comprehensive surface properties of repair parts with an average surface roughness of 1.12 µm, a micro-hardness of 595.22HV and a wear rate of 4.78 × 10−3 mm3/N·m can be obtained with laser finishing. And, the surface roughness and wear rate were reduced by 64.96% and 27.68% respectively, and the micro-hardness can be improved 23.67% compared with the parts without laser finishing. [ABSTRACT FROM AUTHOR]

In the present research, the laser cladding 316 L stainless steel layer with and without exerting electrostatic field were investigated. The microstructure and mechanical properties analyses reveal that the high solidification rate and specific convection result in the grain coarsening by stages and the crystal tends to grow paralleling with the laser scanning direction. Moreover, the rapid solidification also leads to the micro-segregation inside grain. The exerting of electrostatic field opposite to laser scanning direction promotes the elements diffusion and convection in the molten pool, which benefits the directional solidification of the laser cladding layer and produces the columnar grains. In addition, the accelerated diffusion eliminates the micro-segregation but induces the formation of stacking faults inside grains. The exerting of electrostatic field consistent with laser scanning direction restricts the elements diffusion and convection in the molten pool, which results in the ordered mushy solidification and ultrafine grain structure in whole cladding layer. Moreover, the existence of electrostatic field consistent with laser scanning direction promotes the micro-segregation and precipitation of small MC carbides. Compared with the laser cladding layer, the exerting of electrostatic field could decrease the porosity and improve the modulus and hardness of the laser cladding layer except the hardness of dendritic region. The interdendritic region in laser cladding layer with exerting of electrostatic field opposite to laser scanning direction obtains the highest modulus and hardness. • Electrostatic field has been utilized to modify the laser cladding 316L stainless steel layer. • Electrostatic field opposite to laser scanning direction promotes the elements diffusion, benefiting the directional solidification. • Electrostatic field consistent with laser scanning direction restricts the elements diffusion, benefiting the ordered mushy solidification and ultrafine grain structure. • Electrostatic field decreases the porosity, and improves the modulus and hardness. [ABSTRACT FROM AUTHOR]