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In this paper, polypropylene (PP) film samples were obtained at different stretching ratios. The dielectric properties of PP samples were studied. The crystal morphology and orientation degree of the materials were characterized. The findings indicate that the PP film sample with the stretching ratio 5 × 5 has the lowest conductivity and the highest breakdown strength. Moreover, the effect mechanism of the stretching ratio on the dielectric properties of PP films was explored. A reasonable stretching ratio can make the molecular chains of PP aligned, form an orderly crystalline morphology, and improve the crystallinity. When the stretching ratio is too high, the orientation degree of PP will decrease and the spherulite structure will be destroyed, leading to a decrease in dielectric properties. The research results can serve as a reference for improving the dielectric properties of PP films.

In this paper, the surface grafting and crosslinking modification method is proposed for enhancing the dielectric properties of polypropylene (PP) films for metalized film capacitors (MFCs). The results indicate that the leakage conductivity of the modified film is 1.05 × 10−16 S/m, exhibiting better resistance characteristics. The DC breakdown strength could reach 625.2 kV/mm, marking a notable 14.8% increase compared to the pure PP film. The surface grafting could lead to charge concentration at the electrode/film interface, which weakens the interfacial electric field and inhibits charge injection. Furthermore, the crosslinking reaction could enhance the entanglement of macromolecular chains, thereby changing the crystal morphology of PP and decreasing the migration rate of carriers. This method improves the dielectric properties of the capacitor film from the perspective of charge transport.

Metallized film capacitors (MFCs) is the essential components of the superconducting magnetic energy storage (SMES) system. In this paper, a polymer insulation film partial discharge(PD) experimental system is established to explore the PD characteristics of biaxially oriented polypropylene (BOPP) and metallized films based on the simulation of insulation defects formed after the self-healing in MFCs. As the size and quantity of defects increase, the distortion of the electric field intensifies, thereby facilitating the occurrence of PD. However, the PD amplitude of the metallized film decreased by about 10%. The PD of BOPP films is mainly internal discharge. The metallized film initially occurs surface discharge. With the applied voltage increasing, the intensity of internal discharge amplifies. Self-healing and PD will cause the loss of electrodes, leading to the degradation in capacitor performance. The difference in PD characteristics between BOPP and metallized films is attributed to the excellent conductivity of the metallized film surface. This property promotes diffusion and combination of the space charge, while reducing the accumulation of charges in the defects. Thus the electric field distortion is reduced, which makes PD more difficult to occur and less intensive.

In this paper, a method based on irradiation cross-linking modification and crystallization regulation is proposed to improve the dielectric properties of polypropylene (PP) films. Sorbitol nucleating agent DMDBS with different contents is added during the preparation of cross-linked PP film to investigate the influence of nucleating agents on cross-linking modification. The results show that the cross-linked structure restricts the carrier migration behavior under the electric field, leading to a decrease in the conductivity. The doping of nucleating agents increased the nucleation density and the cross-linking degree of the PP films, thus further improving their insulating properties. The cross-linking degree of PP film doped with 0.05 wt% DMDBS is increased to 20.16%. The conductivity was decreased by 36.8%, and the breakdown strength was improved by 18.3% in contrast to pure PP film. The paper provides practical experience for the enhancement of insulating properties of PP films for capacitors.

Polypropylene (PP) is affected by the complex stresses such as electricity and heat for a long time in practical application, and the dielectric breakdown properties often decrease, which significantly lessens the service life of metalized film capacitors. The long-term stability of dielectric materials depends on the process parameter. In this paper, PP samples are prepared with various ash content, and the electrothermal aging test is carried out. The results suggest that after aging, the breakdown strength of the samples with high ash content indicates a reduction of 10.9%. In contrast, the breakdown strength of low ash content PP samples exhibits a decline of merely 3.8%. The matal ash within PP matrix generates initial free radicals during the process of aging degradation under the electrothermal field and catalyzes the decomposition of hydroperoxides to promote the aging reaction process. The research results provide guidance for enhancing the long-term operation performance of PP.

Aim: The study objective was to evaluate the primary feasibility of endoscopic submucosal resection (ESD) and endoscopic full-thickness resection (EFTR) via balloon-assisted enteroscopy (BAE) to treat small bowel subepithelial lesions (SELs). Method: A retrospective case series study was performed. The first fifteen consecutive patients who underwent ESD (n= 10) and EFTR (n= 5) via BAE to remove small bowel SELs from November 2016 to December 2023 were included. The main outcome measures were the technique success rate, operative time and complication rate. Results: This research focused on 15 cases of jejunoileal SELs, four cases of lipomyoma, three cases of ectopic pancreas, two cases of NETs, three cases of benign fibrous tumours and three cases of angioma. The overall technique success rate was 86.7%, with 100% (10/10) and 60% (3/5) for BAE-ESD and BAE-EFTR, respectively, in removing small bowel SELs. Two cases of EFTR failed, as the BAE operation was unsuitable for tumour resection and suture repair of a perforated wound. No serious bleeding or any postoperative complications occurred. The median time of endoscopic resection via BAE for SELs was 44 min (range 22–68 min). Conclusion: ESD and EFTR via BAE might be alternative choices for treating small SELs in the small bowel, with the advantages of clear and accurate positioning and minimal invasiveness. However, its superiority over surgery still needs to be further investigated.

In this article, the terephthalaldehyde/ polypropylene (PP) layer and the parylene (PN)/PP layer are introduced into the membrane near the anode side and cathode side to improve the dielectric properties of PP films. The results indicate that the composite film with 0.02 wt.% terephthalaldehyde and 0.015 wt.% PN in the corresponding functional layer exhibits best. The leakage conductivity declines by 94% at $30~^{\circ }$ C and decreases by 98% at $125~^{\circ }$ C. The charge accumulation rate K drops from 1.74 to 1.05 at $30~^{\circ }$ C and decreases from 2.48 to 1.28 at $125~^{\circ }$ C. The dc breakdown strength is improved by 26%–32%, and the discharged energy density is enhanced by 89%–101%. The introduction of the functional layers will trigger charge trapping effect and form a reverse electric field near the electrode, thereby suppressing the charge injection. This method provides a reference for obtaining films with better insulation performance and energy storage characteristics from the perspective of charge transport.

In this article, the polypropylene after long chain branching was subjected to simultaneous biaxially stretching at different multiplicities to form biaxially oriented modified PP films. Compared with pure PP, long-chain branched polypropylene (LCBPP) has more molecular chain entanglement points, which can inhibit the thermal motion of molecular chains at high temperatures, so it can improve the thermal stability of dielectrics. However, the tangling of molecular chains also suppresses the development of perfect spherical crystals, which limits the performance of LCBPP at room temperature. A higher multiplicity of biaxial stretching can optimize the connections between spherical crystals by stress-induced crystallization and promote the regular arrangement of molecular chains to form dense crystals. The compact aggregated state structure reduces the average free volume and suppresses the acceleration process of carriers within the free volume, so the stretched samples exhibit superior breakdown properties. Therefore, molecular orientation based on the introduction of long-chain branched structures allows further improvement of the dielectric properties of the films.

In this article, the terephthalaldehyde/ polypropylene (PP) layer is introduced to improve the breakdown strength of PP films for power capacitors. The length of the alkoxy group is regulated to explore the promotion effect of terephthalaldehyde. The results indicate that when the number of carbon atoms reaches 8, the leakage conductivity decreases by 92.1% at 30 °C and declines by 95.9% at 125 °C. The charge accumulation rate K decreases from 1.74 to 1.18 at 30 °C and declines from 2.48 to 1.33 at 125 °C. The dc breakdown strength is enhanced by 19%–25%, and the energy density is improved by 68%–70%. The accumulation of holes in the functional layer could suppress the charge injection from the anode and the alkoxy chain growth could enhance the ability of free holes capturing. This method provides a feasible idea to obtain the film with better insulation performance from the perspective of molecular and charge migration.

A Pd-catalyzed asymmetric higher-order dipolar cycloaddition between allenyl carbonates and azadienes is achieved by exploiting novel alkylidene-π-allyl-Pd dipoles. This research provides a modular platform for the synthesis of challenging chiral endocyclic allenes bearing a medium-sized heterocyclic motif and a centrally chiral stereocenter in good yields with high enantio- and diastereoselectivities (29 examples, up to 97% yield, 97:3 er and >19:1 dr). Experimental and computational studies elucidate the possible reaction mechanism and the observed stereochemical results. Based on the mechanistic understanding, a new π-propargyl-Pd dipole was designed to further extend the success of the higher order dipolar cycloaddition strategy to the synthesis of 10-membered endocyclic alkynes from propargyl carbonates and azadienes (13 examples, up to 98% yield and 94.5:5.5 er).

As lithium-ion batteries (LIBs) become more widespread, the number of spent LIBs gradually increases. Until now, recycling of spent LIBs has mainly concentrated on high-value cathodes, but the anode graphite has not yet attracted wide attention. In this work, spent graphite from LIBs was oxidized to graphene oxide and then thermally reduced to reduced graphene oxide (RGO), which serves as the cathode of aqueous Zn dual-ion batteries (ZDIBs). The thermal reduction process enables RGO with a large layer spacing and porous structure, which increase the anion insertion sites and transfer kinetics. As a result, the corresponding battery exhibits a high specific capacity of 96.82 mAh g–1at 1 A g–1, superior rate capability, and a high capacity retention rate of 80% after 2000 cycles. Moreover, RGO gradually transforms into a long-range disordered structure during the cycling process, which provides more transport routes and active sites for anion insertion and thus leads to the increase of capacity. This work combines the recycling of spent graphite with aqueous ZDIBs, realizing the high-value use of spent graphite.

Platinum(II) drugs as a first-line anticancer reagent are limited by side effects and drug resistance. Stimuli-responsive nanosystems hold promise for precise spatiotemporal manipulation of drug delivery, with the aim to promote bioavailability and minimize side effects. Herein, a multitargeting octahedral platinum(IV) prodrug with octadecyl aliphatic chain and histone deacetylase inhibitor (phenylbutyric acid, PHB) at axial positions to improve the therapeutic effect of cisplatin was loaded on the upconversion nanoparticles (UCNPs) through hydrophobic interaction. Followed attachment of DSPE-PEG2000and arginine-glycine-aspartic (RGD) peptide endowed the nanovehicles with high biocompatibility and tumor specificity. The fabricated nanoparticles (UCNP/Pt(IV)-RGD) can be triggered by upconversion luminescence (UCL) irradiation and glutathione (GSH) reduction to controllably release Pt(II) species and PHB, inducing profound cytotoxicity. Both in vitro and in vivo experiments demonstrated that UCNP/Pt(IV)-RGD exhibited remarkable antitumor efficiency, high tumor-targeting specificity, and real-time UCL imaging capacity, presenting an intelligent platinum(IV) prodrug-loaded nanovehicle for UCL-guided dual-stimuli-responsive combination therapy.

Introduction: The replacement intervals for infusion sets may differ among healthcare institutions, which may have an impact on the occurrence of central line-associated bloodstream infections (CLABSI). Nevertheless, there exists a limited amount of high-quality evidence available to assist clinicians in determining the most suitable replacement intervals for infusion sets. Therefore, the objective of this trial is to compare the efficacy of 24-h and 96-h replacement intervals for infusion sets on CLABSI among critically ill adults who have central venous access devices. Methods: This is a multicenter, parallel-group randomized controlled trial that will investigate the effect of infusion set replacement intervals on CLABSI in adult patients admitted to intensive care units (ICUs). The study will enroll 1240 participants who meet the inclusion criteria, which includes being 18 years or older, expected to stay in the ICU for longer than 96 h, and in need of central venous access. Participants will be randomly assigned to either a control group receiving a 96-h replacement interval or a treatment group receiving a 24-h replacement interval. Planned Outcome: The primary outcome of this trial is the rate of CLABSI within 28 days after randomization. Conclusion: This is the first randomized controlled trial to investigate the effects of infusion set replacement at 24-h and 96-h intervals on CLABSI in ICU patients. Trial Registration: ClinicalTrials.gov identifier, NCT05359601.

Epipyrone A is a unique C-galactosylated 4-hydroxy-2-pyrone derivative with an antifungal potential from the fungus Epicoccum nigrum. We elucidated its biosynthesis via heterologous expression and characterized an unprecedented membrane-bound pyrone C-glycosyltransferase biochemically. Molecular docking and mutagenesis experiments suggested a possible mechanism for the heterocyclic C-glycosylation and the importance of a transmembrane helix for its catalysis. These results expand the repertoire of C-glycosyltransferases and provide new insights into the formation of C-glycosides in fungi.

In this article, a modification method based on long-chain branching is proposed to improve the dielectric properties of polypropylene (PP) at high temperature. Long-chain branches are successfully grafted to linear PP using functional group reactions with furfuryl sulfide (FS). When FS is added at the amount of 0.05 wt%, the breakdown strength of the modified film is increased by 17.45% and the leakage conductivity is decreased by 86% at 125 °C. The energy storage density of the modified film is increased by 30.93% (25 °C) and 46.74% (125 °C). Functional monomers can form deep traps to capture electrons, and the long-chain branched structure can enhance the thermal stability of the molecular chain. The carrier concentration inside PP at high temperatures is efficiently reduced by the synergistic effect of functional monomers and long-chain branched structure.

The breakdown strength of polypropylene (PP) used in metalized film capacitors decreases sharply in the high-temperature environment, seriously affecting the stable operation of capacitors. This article proposes a method to improve the dielectric properties by crosslinking modified with UV irradiation. After crosslinking, the thermal stability of the molecular chain was enhanced due to the 3-D network structure, and the density of traps increased. Elevated crosslinking improved the breakdown strength and electrical conductivity of PP films at high temperatures. Results showed that the modified sample with 1.5 wt% of crosslinker addition had a maximum crosslinking degree of 17.8%, with a decrease in conductivity. The breakdown strength was 569.4 kV/mm at 115 °C, which was 16.2% higher compared to original PP. This article provides a new idea for improving the high-temperature dielectric properties of PP films.

This article proposes a method to enhance the dielectric properties of polypropylene (PP) films for capacitors by ultraviolet (UV) irradiation modification. The effect of different photoinitiator contents on the crosslinking reaction is analyzed, and the intrinsic correlation between the crosslinking structure and the insulation properties is investigated. The results show that a moderate amount of benzophenone (BP) addition (1.0 wt%) can improve the degree of dielectric crosslinking, with a gel content of 22.3% for PP10. However, excessive amounts of BP lead to the degradation of molecular chains, increasing small molecular groups within the matrix and causing damage to the polymer insulation. Experiments on direct current (dc) conductivity and breakdown at different temperatures show that the chemically crosslinked network enhances the extent of molecular chain entanglement in the amorphous region, improving the film’s thermal stability at high temperatures. At 115 °C, the breakdown strength of PP10 was 590.5 kV/mm, an increase of 20.5% compared to pure PP. This study provides a viable idea for the reliable application of PP films under electrothermal coupling fields.

This paper describes a technique for improving distribution network dispatch by using the four-quadrant power output of distributed energy storage systems to address voltage deviation and grid loss problems resulting from the large integration of distributed generation into the distribution network. The approach creates an optimization dispatch model for an active distribution network. The objective function aims to minimize power purchase costs, network loss costs, and voltage deviation penalties. In addition, the method employs an interval robust optimization technique to handle uncertainties related to solar turbine output and load demand. To solve the optimal power flow problem for AC in the distribution network, this paper implements the second-order cone relaxation technique to convert it into a solvable second-order cone programming problem. Moreover, the Big-M method is used to handle the nonlinear terms in the objective function. Finally, simulation experiments are conducted on the IEEE33 node system to verify the effectiveness and superiority of the proposed method. The simulation results indicate that the system's operating cost can be significantly reduced. Additionally, it has a positive impact on reducing voltage deviation and system loss, ultimately improving the operation of the distribution network system.

Directional control of thermal emission over its broad wavelength range is a fundamental challenge. Gradient epsilon-near-zero (ENZ) material supporting Berreman mode has been proposed as a promising approach. However, the bandwidth is still inherently limited due to the availability of ENZ materials covering a broad bandwidth and additional undesired omnidirectional modes in multilayer stacking with increased thickness. Here, we show that broadband directional thermal emission can be realized beyond the previously considered epsilon-near-zero and Berreman mode region. We then establish a universal approach based on effective medium theory to realizing ultra-broadband directional thermal emitter. We numerically demonstrate strong (emissivity >0.8) directional (80 ± 5°) thermal emission covering the entire thermal emission wavelength range (5–30 μm) by using only two materials. This approach offers a new capability for manipulating thermal emission with potential applications in high-efficiency information encryption, energy collection and utilization, thermal camouflaging, and infrared detection.

Reconstituted sheet tobacco (RST) is critical to the quality of cigarette. The purpose of this study was to extract and cultivate bacteria from tobacco leaf stalks, scraps, and concentrate from RST production lines. A total of 21 strains with unique morphologies were obtained. Through a series of screening tests, a Bacillus subtilisstrain B-NS-7 was found for its ability to produce high levels of protease, amylase, and pectinase, as well as ferment tobacco concentrate to enhance aroma. The B-NS-7 fermented concentrate had a 48.3% increase in aroma compared to the original concentrate as determined by HS–SPME–GC–MS. The concentrate was inoculated with a 1% volume fraction of the strain and fermented at 37 °C for 24 h to achieve maximum aroma production of 116.3 μg/mL. Among these, neophytadiene was responsible for the majority of the fragrance enhancement, and B-NS-7 was identified as an aldehydic and alkene-flavored strain with superior sensory quality to the original liquid. This strain has been deposited at the China General Microbiological Culture Collection Center (CGMCC No. 23716). By way of this study, B. subtilisB-NS-7 was intended to be used in the manufacturing of RST through microbial fermentation to improve the quality, and the fermentation conditions for aroma creation were optimized, providing suggestions for the microbial development of the RST industry.

Photocatalytic water splitting for hydrogen production provides a viable approach to address the energy crisis. However, the sluggish four-electron water oxidation severely restricts water splitting efficiency. Herein, with the Mo-doped ZnIn2S4(Mo-ZIS) photocatalyst, the hydrogen production reaction is significantly facilitated through synergistic integration with the kinetically favourable oxidation of benzyl alcohol (BA). The high-valence and unsaturated Mo species promote not only the separation of photo carriers but also the activation of BA, thereby accelerating the oxidation of BA. Moreover, Mo doping adjusts the band structure of ZIS, enhancing the oxidation capability of the photocatalyst without inducing the excessive oxidation of BA. Consequently, Mo-ZIS efficiently produces both high-value-added H2and benzaldehyde (BAD) products, exhibiting a remarkable hydrogen evolution rate (16,353 µmol g−1h−1) and BAD yield (13,942 µmolg−1h−1) without the need for additional noble-metal cocatalysts, significantly surpassing the performance of pristine ZIS photocatalysts. Strikingly, by modulating the desorption process of intermediates on the Mo-ZIS surface through adjusting the hydrogen bonding network strength between BA and the solvent, the BAD production rate of Mo-ZIS is 23,068 µmol g−1h−1, resulting in a 65% increase compared to acetonitrile solution. This work introduces a valuable strategy for combining photocatalytic hydrogen production with selective organic product transformation, providing new insights for the development of novel photocatalysts to achieve efficient solar energy conversion.

The dielectric properties of polypropylene (PP) for metalized film capacitors deteriorate severely at high temperatures. This article proposes a method to improve the dielectric strength of PP by introducing crosslinked structure. Compared with the original PP, the study shows that the crosslinking reaction creates chemical bonding linkages between the molecular chains and reduces the interchain distance, thereby inhibiting the mobility of the chain segments at high temperatures and weakening the free volume change at high temperatures. The traps introduced by the crosslinking points enhance the capture of carriers and reduce the electrical conductivity. At 115 °C, the breakdown strength of the modified films is enhanced by 20.2%, and the conductivity is reduced by 97.5%. In addition, the effect of irradiation time on the UV crosslinking reaction was investigated. The results show that the film properties can be improved at an irradiation time of 90 s. This method guides improving the PP high-temperature insulation from the molecular chain structure regulation perspective.

This paper studies the joint three-dimensional (3D) deployment and beamforming problem for a rate-splitting multiple access (RSMA)-enabled unmanned aerial vehicle base station (UBS) assisted by geographic information. Specifically, we maximize the minimum achievable rate among users by optimizing the beamforming, rate allocation and UBS deployment considering the power and building blockages constraints. To solve the intractable problem, an alternating optimization scheme is proposed. In particular, we first split the formulated problem into three sub-problems of deployment region modeling, joint beamforming and rate allocation, and 3D UBS deployment. For the first sub-problem, we define the allowable deployment region with geographic information with the aim of ensuring line-of-sight connections between the UBS and users. The feasible region is expressed as tractable constraints via the Big-M method and penalty function method. For the other sub-problems, semi-definite programming and successive convex approximation are employed to design the joint beamforming and rate allocation, and UBS deployment, respectively. These two sub-problems are optimized iteratively until convergence. Finally, numerical results validate the superiority of our proposed solution in comparison with the benchmark schemes with regard to the minimum achievable rate.

Neurofibromatosis type 1 associated plexiform neurofibroma (pNF) is characterized by abundant fibroblasts and dense collagen, yet the intricate interactions between tumor-origin cells (Schwann cells) and neurofibroma-associated fibroblasts (NFAFs) remain elusive. Employing single-cell RNA sequencing on human pNF samples, we generated a comprehensive transcriptomics dataset and conducted cell-cell communication analysis to unravel the molecular dynamics between Schwann cells and NFAFs. Our focus centered on the pleiotrophin (PTN)/nucleolin (NCL) axis as a pivotal ligand-receptor pair orchestrating this interaction. Validation of PTN involvement was affirmed through coculture models and recombinant protein experiments. Functional and mechanistic investigations, employing assays such as CCK8, EdU, Western Blot, ELISA, Hydroxyproline Assay, and Human phospho-kinase array, provided critical insights. We employed siRNA or inhibitors to intercept the PTN/NCL/proline-rich Akt substrate of 40 kDa (PRAS40) axis, validating the associated molecular mechanism. Our analysis highlighted a subset of Schwann cells closely linked to collagen deposition, underscoring their significance in pNF development. The PTN/NCL axis emerged as a key mediator of the Schwann cell-NFAF interaction. Furthermore, our study demonstrated that elevated PTN levels enhanced NFAF proliferation and collagen synthesis, either independently or synergistically with TGF-β1 in vitro. Activation of the downstream molecule PRAS40 was noted in NFAFs upon PTN treatment. Crucially, by targeting NCL and PRAS40, we successfully reversed collagen synthesis within NFAFs. In conclusion, our findings unveil the pivotal role of the PTN/NCL/PRAS40 axis in driving pNF development by promoting NFAFs proliferation and function. Targeting this pathway emerges as a potential therapeutic strategy for pNF. This study contributes novel insights into the molecular mechanisms governing pNF pathogenesis.

In this article, a method for enhancing the dielectric properties of polypropylene (PP) films based on crosslinking modification by gamma irradiation is presented. The effect of crosslinked structure on the dielectric properties of PP films is investigated by varying the gamma irradiation dose and the content of the sensitizer pentaerythritol triacrylate (PETA). Crosslinking forms a 3-D network structure in the amorphous region, and its strong intermolecular forces improve the thermal stability of PP. The slip and relaxation of molecular chains at high temperatures are restricted after crosslinking, thus limiting carrier transport in PP and contributing to low electrical conductivity and high breakdown strength. The results indicate that the maximum crosslinking degree of the modified samples reached 25.6% at the irradiation dose of 5 kGy and the sensitizer content of 1 wt%. The permittivity of the crosslinked films increases, and the conductivity decreases significantly at high temperatures. The breakdown strength of the crosslinked film is 595.4 kV/mm at 115 °C, which is 20.9% higher compared to PP. The maximum theoretical energy storage density after the modification reaches 3.48 J/cm3 (115 °C), which is 47.5% higher than PP. This article provides feasible ideas for enhancing the dielectric properties of PP films at high temperatures.

In this article, a modification method based on gamma ( $\gamma $ )-ray irradiation and applied to polypropylene (PP) films is proposed to enhance the dielectric properties for high-voltage direct current (HVdc) capacitors. With the addition of 0.2 wt% trimethylolpropane triacrylate (TMPTA), PP films are irradiated at doses of 0, 2, 5, and 10 kGy. The addition of sensitizer contributed to improving the crosslinking density of PP under the appropriate irradiation dose and the gel content can reach 22.54%. Experimental results show that dielectric loss and conductivity are decreased significantly after modification. Additionally, the breakdown strength of the modified films shows an increase of 13.8% and the energy density increases by 28.7% at 115 °C. It is found that the crosslinking of molecular chains forms stable 3-D network structures and improves the intermolecular forces, restricting transportation of charge carriers, which improves dielectric properties and the thermal stability of PP at high temperatures.

The replacement of WC-Co cermet coating partially or entirely has evolved as one of the most promising research hotspots in terms of coating properties as well as economic reasons. In this study, the TiC reinforced AlCoCrFeNi high entropy alloy (HEA) composite coating based on new sintering method was explored. Firstly, the combination of spray drying and plasma spheroidization is proposed to fabricate TiC/HEA composite powder for thermal spraying application. After that, the corresponding composite coating was deposited by high velocity air-fuel (HVAF) process. The results show that the developed TiC/HEA powder has a more compact structure and higher sphericity, which helps to improve powder fluidity, meanwhile, with 50 wt% TiC incorporation, the porosity、hardness、bonding strength and fracture toughness of TiC/HEA composite coating are 0.8 % 765.2 HV0.3,68.1 Mpa and 2.7 MPa m−1/2, respectively, showing simultaneous hardening, densifying and toughening effects after introducing dual-sized TiC particles. Besides, the good wear performances of TiC/HEA composite coating including low wear rate (4.2 × 10−5 mm3 N−1 m−1) and coefficient of friction (0.34) are obtained，indicating a valuable application prospect. In addition, the wear mechanisms of TiC/HEA composite coating are determined by abrasive and oxidation wears and that of grinding ball is abrasive wear and adhesive wears.

Key Message: Genome-wide identification of C2H2-ZF gene family in the poly- and mono-embryonic citrus species and validation of the positive role of CsZFP7in sporophytic apomixis. Abstract: The C2H2 zinc finger (C2H2-ZF) gene family is involved in plant vegetative and reproductive development. Although a large number of C2H2 zinc-finger proteins (C2H2-ZFPs) have been well characterized in some horticultural plants, little is known about the C2H2-ZFPs and their function in citrus. In this work, we performed a genome-wide sequence analysis and identified 97 and 101 putative C2H2-ZF gene family members in the genomes of sweet orange (C. sinensis, poly-embryonic) and pummelo (C. grandis, mono-embryonic), respectively. Phylogenetic analysis categorized citrus C2H2-ZF gene family into four clades, and their possible functions were inferred. According to the numerous regulatory elements on promoter, citrus C2H2-ZFPs can be divided into five different regulatory function types that indicate functional differentiation. RNA-seq data revealed 20 differentially expressed C2H2-ZF genes between poly-embryonic and mono-embryonic ovules at two stages of citrus nucellar embryogenesis, among them CsZFP52specifically expressed in mono-embryonic pummelo ovules, while CsZFP7, 37, 44, 45, 67 and 68 specifically expressed in poly-embryonic sweet orange ovules. RT-qPCR further validated that CsZFP7specifically expressed at higher levels in poly-embryonic ovules, and down-regulation of CsZFP7in the poly-embryonic mini citrus (Fortunella hindsii) increased rate of mono-embryonic seeds compared with the wild type, indicating the regulatory potential of CsZFP7in nucellar embryogenesis of citrus. This work provided a comprehensive analysis of C2H2-ZF gene family in citrus, including genome organization and gene structure, phylogenetic relationships, gene duplications, possible cis-elements on promoter regions and expression profiles, especially in the poly- and mono-embryogenic ovules, and suggested that CsZFP7is involved in nucellar embryogenesis.

In this article, an experimental system is established to characterize the internal, surface, and corona partial discharge (PD) properties of polypropylene films under a magnetic field. With the increase of the magnetic flux density, the PD inception voltage in various defects is reduced by 5%–12%. At the same time, the number of discharges under the magnetic field increases by 126%, 183%, and 61%, respectively. The magnetic field changes the charge-moving direction and reshapes the charge distribution through the Lorentz force. The influence of the magnetic field on internal discharge in the negative half cycle is more significant, by exciting electrons and distorting the electric field. The proportion of PD in the negative half cycles increases from 58.4% to 71.8%. The change of discharge characteristics on the surface is mainly reflected in the broadening of the discharge phase, which is due to the recombination of bipolar charges separated by the magnetic field and accumulated on the surface of the sample. The corona discharge ratio in the positive half voltage cycles increases from 9.50% to 22.1%, although it is still far less than that in the negative half voltage cycles. The trajectory of electrons in the air is changed by the magnetic field, which enhances the electric field near the high-voltage electrode in the positive half cycles.

In this article, an experimental device is designed to characterize the asymmetric distribution of charges caused by charge deflection under a magnetic field in the polypropylene (PP) dielectric. Under the magnetic field, the electric potential difference caused by the asymmetric distribution of charges appears on both sides of the sample. The potential difference increases with the enhancement of the magnetic field. The stronger electric field also promotes the accumulation of asymmetric charges. In addition, the charge packet phenomenon is observed in this experiment. Increasing the magnetic field can accelerate the charge packets to reach the dynamic equilibrium, and the enhanced electric field drives the charge packet to move faster toward the opposite electrode.

Physalis angulataLinn. is an exotic Amazonian fruit that is commonly recognized as wild tomato, winter cherry, and gooseberry. While its fruit is known to contain many nutrients, such as minerals, fibers, and vitamins, few papers have investigated withanolide derivatives from its fruits. UPLC-Q-Orbitrap-MS/MS, which produces fragmentation spectra, was applied for the first time to guide the isolation of bioactive withanolide derivatives from P. angulatafruits. As a result, twenty-six withanolide derivatives, including two novel 1,10-secowithanolides (1and 2) and a new derivative (3), were obtained. Compounds 1and 2are rare rearranged 1,10-secowithanolides with a tetracyclic 7/6/6/5 ring system. All structures were assigned through various spectroscopic data and quantum chemical calculations. Nine withanolide derivatives exhibited significant inhibitory effects on three tumor cell lines with IC50values of 0.51–13.79 μM. Moreover, three new compounds (1–3) exhibited potential nitric oxide inhibitory effects in lipopolysaccharide-stimulated RAW264.7 cells (IC50: 7.51–61.8 μM). This investigation indicated that fruits of P. angulatacould be applied to treat and prevent cancer and inflammatory-related diseases due to their potent active withanolide derivatives.

Microglia are specialized brain-resident macrophages that arise from primitive macrophages colonizing the embryonic brain1. Microglia contribute to multiple aspects of brain development, but their precise roles in the early human brain remain poorly understood owing to limited access to relevant tissues2–6. The generation of brain organoids from human induced pluripotent stem cells recapitulates some key features of human embryonic brain development7–10. However, current approaches do not incorporate microglia or address their role in organoid maturation11–21. Here we generated microglia-sufficient brain organoids by coculturing brain organoids with primitive-like macrophages generated from the same human induced pluripotent stem cells (iMac)22. In organoid cocultures, iMac differentiated into cells with microglia-like phenotypes and functions (iMicro) and modulated neuronal progenitor cell (NPC) differentiation, limiting NPC proliferation and promoting axonogenesis. Mechanistically, iMicro contained high levels of PLIN2+lipid droplets that exported cholesterol and its esters, which were taken up by NPCs in the organoids. We also detected PLIN2+lipid droplet-loaded microglia in mouse and human embryonic brains. Overall, our approach substantially advances current human brain organoid approaches by incorporating microglial cells, as illustrated by the discovery of a key pathway of lipid-mediated crosstalk between microglia and NPCs that leads to improved neurogenesis.

The tracking control for multiple Euler-Lagrange systems with external disturbances in finite time under undirected topology is investigated in this paper. A dynamic model is established for the multi-EL systems to accurately describe the general mechanical system. Furthermore, an integral terminal sliding mode surface is devised to converge the tracking errors of the system state to a neighborhood of zero within finite time, and the designed finite-time controller ensures fast convergence and high steady-state accuracy. To reduce the controller update frequency and network transmission communication load, a dynamic event-triggered mechanism is introduced between the sensor and controller, and no Zeno behavior was observed. Therefore, the Lyapunov stability theory and finite-time stability criterion prove that all signals in the closed-loop system are uniformly ultimately bounded in finite time. Finally, the simulation results verified the effectiveness of the proposed control method.

The peer merit review of research proposals has been the major mechanism to decide grant awards. However, research proposals have become increasingly interdisciplinary. It has been a longstanding challenge to assign interdisciplinary proposals to appropriate reviewers so proposals are fairly evaluated. One of the critical steps in reviewer assignment is to generate accurate interdisciplinary topic labels for proposal-reviewer matching. Existing systems mainly collect topic labels manually generated by principle investigators. However, such human-reported labels can be non-accurate, incomplete, labor intensive, and time costly. What role can AI play in developing a fair and precise proposal reviewer assignment system? In this study, we collaborate with the National Science Foundation of China to address the task of automated interdisciplinary topic path detection. For this purpose, we develop a deep Hierarchical Interdisciplinary Research Proposal Classification Network (HIRPCN). Specifically, we first propose a hierarchical transformer to extract the textual semantic information of proposals. We then design an interdisciplinary graph and leverage GNNs to learn representations of each discipline in order to extract interdisciplinary knowledge. After extracting the semantic and interdisciplinary knowledge, we design a level-wise prediction component to fuse the two types of knowledge representations and detect interdisciplinary topic paths for each proposal. We conduct extensive experiments and expert evaluations on three real-world datasets to demonstrate the effectiveness of our proposed model.