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Edaravone is an important free radical scavenger with significant efficacy in acute ischemic stroke (AIS) patients, which is essential in medical research. The solubility data of edaravone were measured by the static gravimetric method in 12 pure solvents (2-butanone, 4-methyl-2-pentanone, hexane, 1,2-dichloroethane, 3-methyl-1-butanol, ethyl lactate, dimethyl carbonate, butyl acetate, methyl acetate, isopropyl acetate, isobutyl acetate, and propyl acetate) from 283.15 to 323.15 K and 101.2 kPa. The solubility of edaravone in all studied solvents increased with the increase of temperature. At 298.15 K, the solubility order of edaravone was: 1,2-dichloroethane (0.04168 mol/mol) > ethyl lactate (0.03918 mol/mol) > 2-butanone (0.03722 mol/mol) > 3-methyl-1-butanol (0.02609 mol/mol) > 4-methyl-2-pentanone (0.02432 mol/mol) > methyl acetate (0.02372 mol/mol) > propyl acetate (0.02279 mol/mol) > dimethyl carbonate (0.02011 mol/mol) > butyl acetate (0.01953 mol/mol) > isobutyl acetate (0.01419 mol/mol) > isopropyl acetate (0.01621 mol/mol) > hexane (0.0005202 mol/mol). The Hansen solubility parameters (HSPs) were utilized to assess the solvents’ capability and to elucidate their ability to dissolve edaravone. The data obtained are partially in agreement with the analyses of the HSPs. The main factors influencing the solubility behavior included the empirical solvent polarity parameters (ET(30)), hydrogen bonding, and cohesive energy density. It was found that the most important factor affecting the solubility of edaravone was the polarity of the solvent. Three solubility fitting models were used to correlate the experimental mole fraction solubility data, including the modified Apelblat model, the NRTL model, and the UNIQUAC model. At the same time, the model parameters and data deviation values were calculated. The results showed that the modified Apelblat model had better correlation results. Furthermore, mixing thermodynamic characteristics of edaravone in selected solvents were calculated by the NRTL model, which revealed that the mixing process was spontaneous and entropy-driven. The aim of this study was to supplement the solubility data of edaravone in pure solvents and provide data support for the production of its crystals with higher medicinal values.

Optimizing edge caching is crucial for the advancement of next-generation (nextG) wireless networks, ensuring high-speed and low-latency services for mobile users. Existing data-driven optimization approaches often lack awareness of the distribution of random data variables and focus solely on optimizing cache hit rates, neglecting potential reliability concerns, such as base station overload and unbalanced cache issues. This oversight can result in system crashes and degraded user experience. To bridge this gap, we introduce a novel digital twin-assisted optimization framework, called D-REC, which integrates reinforcement learning (RL) with diverse intervention modules to ensure reliable caching in nextG wireless networks. We first develop a joint vertical and horizontal twinning approach to efficiently create network digital twins, which are then employed by D-REC as RL optimizers and safeguards, providing ample datasets for training and predictive evaluation of our cache replacement policy. By incorporating reliability modules into a constrained Markov decision process, D-REC can adaptively adjust actions, rewards, and states to comply with advantageous constraints, minimizing the risk of network failures. Theoretical analysis demonstrates comparable convergence rates between D-REC and vanilla data-driven methods without compromising caching performance. Extensive experiments validate that D-REC outperforms conventional approaches in cache hit rate and load balancing while effectively enforcing predetermined reliability intervention modules.

To fully suppress the current harmonics of torque plane and zero-sequence dimension in open-end winding (OW) permanent-magnet synchronous motor (PMSM), a novel 3-D space vector pulsewidth modulation (SVPWM) strategy is proposed in this article. First, the distribution of 3-D space vectors is analyzed. Then, a subspace-based vector selection method is developed to utilize the adjacent vectors in space to synthesize the reference vector. On this basis, a repetitive controller is equipped for zero-sequence current to guarantee precise current tracking. By using the proposed 3D-SVPWM strategy, the current controls in 3D can be well balanced. Besides, the fault-tolerant control of open-phase fault in OW PMSM drive is realized with the proposed 3D-SVPWM strategy by simply changing zero-sequence current reference. The experiments are carried out to prove the effectiveness of the proposed strategy.

To solve the asymmetric problems of each phase caused by the different relative positions of the armature coils and excitation sources (PMs and excitation coils) in traditional three-phase hybrid-excited doubly salient generator (HEDSG), a novel HEDSG with long pitch field sources is proposed in this paper. Because of the adoption of excitation winding wound around the PMs sandwiched “four-teeth”, the symmetric magnetic circuits among phases can be achieved, thus the balanced three-phase back electromotive force (EMF) curves can be obtained. First, the configuration of proposed HEDSG is described, based on which its operation principle is discussed from the perspective of magnetic circuits. Besides, the flux regulation principle is analyzed based on the simplified equivalent magnetic circuit model. Then, a multi-step design optimization method is implemented to determine optimal structural parameters. Whereafter, the effect of the bidirectional excitation on the static and dynamic performances of the proposed HEDSG is investigated, which demonstrates it has a strong flux regulation ability. Furthermore, a comparative study between the proposed and traditional HEDSGs is conducted. It is shown that the proposed HEDSG can essentially solve the asymmetric problem among phases and possesses the merits of lower cogging torque and higher output power. Finally, a prototype of the proposed HEDSG is fabricated and tested so as to experimentally verify the analysis and simulation.

DC microgrid (DCMG) is characterized by a high degree of power electronics, low system inertia, and CPL (CPL) with a negative damping feature. Its system-level transient stability is of great concern. The stability of a DCMG system is affected by many factors, such as component parameters, load types, converter control methods, etc. To analyze the system-level stability of the DCMG, the constraints of large signal stability of the DCMG based on droop control are derived by using the Lyapunov direct method. Based on this conclusion, the influence of system parameters on large signal stability and voltage deviation of the DCMG is revealed, and the optional range of filter element parameters and droop coefficient under the stability and voltage constraints is proposed. The parameter selection work involves two evaluation indicators, system stability, and voltage deviation. This article uses the variable weight coefficient method to normalize these two indicators into a comprehensive evaluation index, and the appropriate droop coefficient is selected based on the optimal comprehensive evaluation index. The work of this article has reference values for the parameter design of the DCMG system components and the selection of the droop coefficient.

Due to the weak network architecture of mountainous power grid rich in grid-connected small hydropower, once the small hydropower units operate independently as a network when the upper power grid fails and loses power, the reliability of the power supply could be effectively improved. To cope with the problem of insufficient frequency regulation capacity of small hydropower units and the large risk of separation fault, this paper proposes a piecewise variable coefficient PID control strategy which improves the speed regulation control strategy of hydropower units, and a joint frequency regulation strategy of hydropower energy storage is designed to optimize the system operation state. Based on the MATLAB simulation platform, a hydropower energy storage microgrid model of mountainous power grid was built to verify the effectiveness of the segmented variable parameter control strategy. Using the proposed control strategy, the hydropower intelligent control terminal was developed and put into application in a certain area of Guangdong. Through simulation analysis and engineering applications, the practicality of the application of device engineering is verified to have good application and promotion value for a multi-hydropower mountainous power grid.

Coupling hydrogen production with selective organic synthesis in one cooperative manner offers a novel strategy for green synthesis by virtue of the photogenerated carriers. Herein, a dual-functional photocatalyst of CoSx/Cd0.7Zn0.3S without noble metals is reported for efficient selective benzaldehyde (BAD) synthesis coupled with H2production. The CoSx/Cd0.7Zn0.3S composite showed a higher photocatalytic performance than Cd0.7Zn0.3S and 1 wt% Pt/Cd0.7Zn0.3S, which was attributed to the loaded CoSx, as the cocatalyst, which could accumulate the photogenerated electrons from Cd0.7Zn0.3S, promote the separation of photogenerated charge carriers, and reduce the overpotential of hydrogen production. This study provides a new strategy for the design and synthesis of low-cost, high-efficiency composite materials for photocatalytic efficient selective benzaldehyde (BAD) synthesis coupled with H2production.

Engineering a system with a high mass fraction of active ingredients, especially water-soluble proteins, is still an ongoing challenge. In this work, we developed a versatile surface camouflage strategy that can engineer systems with an ultrahigh mass fraction of proteins. By formulating protein molecules into nanoparticles, the demand of molecular modification was transformed into a surface camouflage of protein nanoparticles. Thanks to electrostatic attractions and van der Waals interactions, we camouflaged the surface of protein nanoparticles through the adsorption of carrier materials. The adsorption of carrier materials successfully inhibited the phase transfer of insulin, albumin, β-lactoglobulin, and ovalbumin nanoparticles. As a result, the obtained microcomposites featured with a record of protein encapsulation efficiencies near 100% and a record of protein mass fraction of 77%. After the encapsulation in microcomposites, the insulin revealed a hypoglycemic effect for at least 14 d with one single injection, while that of insulin solution was only ∼4 h.

Neuroinflammation following spinal cord injury usually aggravates spinal cord damage. Many inflammatory cytokines are key players in neuroinflammation. Owing largely to the multiplicity of cytokine targets and the complexity of cytokine interactions, it is insufficient to suppress spinal cord damage progression by regulating only one or a few cytokines. Herein, we propose a two-pronged strategy to simultaneously capture the released cytokines and inhibit the synthesis of new ones in a broad-spectrum manner. To achieve this strategy, we designed a core/shell-structured microcomposite, which was composed of a methylprednisolone-incorporated polymer inner core and a biocompatible polydopamine outer shell. Thanks to the inherent adhesive nature of polydopamine, the obtained microcomposite (MP-PLGA@PDA) efficiently neutralized the excessive cytokines in a broad-spectrum manner within 1 day after spinal cord injury. Meanwhile, the controlled release of immunosuppressive methylprednisolone reduced the secretion of new inflammatory cytokines. Benefiting from its efficient and broad-spectrum capability in reducing the level of cytokines, this core/shell-structured microcomposite suppressed the recruitment of macrophages and protected the injured spinal cord, leading to an improved recovery of motor function. Overall, the designed microcomposite successfully achieved the two-pronged strategy in cytokine neutralization, providing an alternative approach to inhibit neuroinflammation in the injured spinal cord.

Developing high-efficiency photocatalysts for CO2photoreduction is one of the potential solutions to address both energy and pollution issues. In this study, α-Fe2O3modified La2Ti2O7was successfully synthesized with intimate contact between La2Ti2O7and α-Fe2O3, greatly facilitating the carrier separation and transfer during the photocatalytic reaction. The activity and stability for photocatalytic CO2reduction over α-Fe2O3/La2Ti2O7were significantly improved as compared with the La2Ti2O7substrate. The optimized 3% α-Fe2O3/ La2Ti2O7composite showed excellent CO2reduction activity after 5 h consecutive illumination, and the total utilized photoelectron number (UPN) reached 7.76 μmol, which was about 4.4 times higher than that of the pristine La2Ti2O7. The steady-state photoluminescence spectra, time-resolved photoluminescence spectra (TRPL) and photocurrent response results showed that the improved charge separation efficiency was the key factor to enhance the photocatalytic activity. This work provides novel insights into the design and fabrication of photocatalysts of high performance for CO2reduction for solar-to-energy applications.

In this paper, a small hydropower microgrid solution with high applicability is proposed to solve the problem of high line failure rate and long maintenance time, which can improve the reliability of distribution network in mountainous areas. In this scheme, small hydropower and local load constitute a low-cost but efficient microgrid operation to improve the reliability of rural electricity. In this scheme, small-sized hydropower and local load constitute microgrid operation. In case of failure, the scheme makes full use of the independent operation of microgrid to provide qualified power quality to local load. This scheme is easy to realize and does not need additional energy storage, so it has good economy. Firstly, the frequency disturbance characteristics of small hydropower microgrid is analyzed, which lays a theoretical foundation for small hydropower microgrid operation. Then it introduces the island operation mode to grid-connected operation mode transition of small hydropower, including the key technologies such as frequency adjustment strategy in island operation stage. Finally, the simulation studies show the effectiveness of the method.

The rate of retear after surgical repair remains high. Mesenchymal stem cells (MSCs) have been extensively employed in regenerative medicine for several decades. However, safety and ethical concerns constrain their clinical application. Tendon Stem/Progenitor Cells (TSPCs)-derived exosomes have emerged as promising cell-free therapeutic agents. Therefore, urgent studies are needed to investigate whether TSPC-Exos could enhance tendon-bone healing and elucidate the underlying mechanisms. In this study, TSPC-Exos were found to promote the proliferation, migration, and expression of fibrogenesis markers in BMSCs. Furthermore, TSPC-Exos demonstrated an ability to suppress the polarization of M1 macrophages while promoting M2 macrophage polarization. In a rat model of rotator cuff repair, TSPC-Exos modulated inflammation and improved the histological structure of the tendon-bone interface, the biomechanical properties of the repaired tendon, and the function of the joint. Mechanistically, TSPC-Exos exhibited high expression of miR-21a-5p, which regulated the expression of PDCD4. The PDCD4/AKT/mTOR axis was implicated in the therapeutic effects of TSPC-Exos on proliferation, migration, and fibrogenesis in BMSCs. This study introduces a novel approach utilizing TSPC-Exos therapy as a promising strategy for cell-free therapies, potentially benefiting patients with rotator cuff tear in the future.

The Elongator complex is conserved in a wide range of species and plays crucial roles in diverse cellular processes. We have previously shown that the Elongator protein PoELp3 was involved in the asexual development, pathogenicity, and autophagy of the rice blast fungus. In this study, we further revealed that PoElp3 functions via tRNA-mediated protein integrity. Phenotypic analyses revealed that overexpression of two of the tRNAs, tK(UUU) and tQ(UUG) could rescue the defects in ΔPoelp3strain. TMT-based proteomic and transcriptional analyses demonstrated that 386 proteins were down-regulated in ΔPoelp3strain compared with wild type strain Guy11, in a transcription-independent manner. Codon usage assays revealed an enrichment of Glutamine CAA-biased mRNA in the 386 proteins compared with the 70-15 genome. In addition to those reported previously, we also found that PoErp9, a sphingolipid C9-methyltransferase, was down-regulated in the ΔPoelp3strain. Through an ILV2-specific integration of PoERP9-GFPinto the wild type and ΔPoelp3strain, we were able to show that PoErp9 was positively regulated by PoElp3 translationally but not transcriptionally. Functional analyses revealed that PoErp9 was involved in the fungal growth, conidial development, pathogenicity, and TOR-related autophagy homeostasis in P. oryzae. Taken together, our results suggested that PoElp3 acts through the tRNA-mediated translational efficiency to regulate asexual development, pathogenicity, sphingolipid metabolism, and autophagy in the rice blast fungus.

The exploration of safe and efficient antibiotic-free antimicrobial agents, harboring the capacities of concurrent antibacterial and wound healing, are highly desired to combat the drug-resistance bacteria. In this report, a nanord-like crown ether-based porous organic polymer (CEP-POP) with intrinsic antibacterial activity containing porphyrin unites, was facilely prepared, which was implemented as a carrier to deposit silver nitroprusside nanoparticles (abbreviated as AgNNPs), denoted as CEP-POP-AgNNP. CEP-POP-AgNNP could effectively address the issues of Ag-based bactericide, which not only significantly enhance the stability of Ag-based bactericide, but also greatly reduce the toxicity to normal tissues. Bacteriostatic study demonstrated CEP-POP-AgNNP could function as a broad-spectrum antibacterial agent with superb synergistic bactericidal activity, whose bactericide rate reached 97.7 ± 0.5 % and 90.7 ± 0.5 %, towards E. coliand S. aureus, respectively, at an extremely low inhibitory concentration (5 μg mL−1), far exceeding the as-reported POP-based antimicrobials. Meanwhile, in vivo experiment on mice validated CEP-POP-AgNNP could further enhance the wound healing in synergy with the antibacterial effect. Hence, this novel but simple Ag immobilization strategy paves a new avenue for the rational design of antibiotic-free antimicrobial agents.

The penetration of CaO–MgO–Al2O3–SiO2(CMAS) is one of the most significant factors that induce the failure of air-plasma-sprayed thermal barrier coatings (APS TBCs). The direct penetration of CMAS changes the thermal/mechanical properties of the top coat (TC) layer, which affects the thermal mismatch stress behavior and the growth of thermally grown oxide (TGO) at the TC/bond coat (BC) interface, thereby resulting in a more complicated interface stress state. In the present study, a two-dimensional global model of APS TBCs with half of the TC layer penetrated by CMAS is established to investigate the effect of non-uniform CMAS penetration on the interface stress behavior. Subsequently, a local model extracted from the global model is established to investigate the effects of interface morphologies and CMAS penetration depth. The results show that non-uniform CMAS penetration causes non-uniform TGO growth in APS TBCs, which consequently causes the stress behavior to vary along the interface. Furthermore, the CMAS penetration depth imposes a significant effect on the TC/TGO interface stress behavior, whereas the interface roughness exerts a prominent effect on the stress level at the BC/TGO interface under CMAS penetration. This study reveals the mechanism associated with the effect of non-uniform CMAS penetration on the interface stress behavior in APS TBCSs.

Strong earthquakes can cause different kinds of hydrological responses, and several mechanisms have been suggested to explain them. Verification of these mechanisms, however, is often lacking. Here we test some hypotheses with a laboratory experiment, in particular the hypothesis that dynamic strain mobilizes trapped water in the unsaturated zone. We construct a sand chamber, partially saturated with water, and subject it to “seismic” shaking of controlled energy. Pore pressure in the saturated and unsaturated zones is monitored before and after shaking. We identify three distinct mechanisms: consolidation of sediments in the saturated zone, release of capillary water from the capillary fringe, and mobilization of isolated pore water in the unsaturated zone. Each mechanism may cause pore pressure in the saturated zone to suddenly increase with shaking, and each may offer new insights to understand the source of the extra water and other shallow hydrological responses that appear after earthquakes. Earthquakes interact with water in a variety of interesting ways. For instance, during earthquakes, streamflow and groundwater level may increase, as occurred following the recent earthquake swarm in Puerto Rico. The mechanisms for such changes, however, are still unclear. In our paper, we measure the response of groundwater pressure to seismic shaking to test the hypothesis that earthquakes can cause shallow groundwater to flow toward streams. To accomplish this, we built a tall sand column, filled it with water, and instrumented it with sensors that measure how the pressure of water between sand grains (pore pressure) responds when the chamber is shaken by an impact. We found that “trapped” water in the shallow subsurface, which is held in place by adhesive forces between sand and water, can be released to the water table by seismic shaking, where it can then flow toward a stream. We test mechanisms for groundwater response to earthquakes by performing laboratory experimentsWe observe consolidation of sediments, mobilization of pore water, and release of capillary water from the capillary fringeThese mechanisms can help explain coseismic increases in groundwater level and streamflow when there are no other apparent water sources