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With the extensive use of high-power electronic appliances, polymer-based thermal insulation composites with excellent thermal properties are utilized in the field of heat management with the aim of improving heat dissipation. Due to the high thermal conductivity and good electrical insulation, boron nitride (BN) is rendered as a superior candidate material for thermally conductive fillers. However, the thermal conduction of the composites is inevitably hampered by the interfacial resistance between BN and the polymer matrix. In this work, BN surface was modified by dopamine hydrochloride (PDA) and phenyltrimethoxysilane to enhance its interface compatibility with the polymer matrix. Meanwhile, by applying pressure to the composites during processing, BN grains inside the composite were well aligned to the direction parallel to the heat flow, thereby improving the through-plane thermal conductivity. When the filler content is fixed at 31 vol%, the thermal conductivity of the phenyl silicone rubber (PVMQ)-based composite prepared from modified BN (mark as M-BN/PVMQ) reaches 1.642 W/(m·K), nearly equal to nine times the value for the pure PVMQ matrix (0.18 W/(m·K)). Furthermore, in a nitrogen atmosphere, the initial decomposition temperature (T5%) reaches 512 °C, 172 °C higher than that of pure PVMQ (340 °C). The improved thermal stability of the composites prepared from modified BN resulted from the enhanced interfacial effect, which was analyzed by thermogravimetric infrared gas mass spectrometry system (TG-IR-GC/MS). The high thermal conductivity and stability enable the M-BN/PVMQ composite a promising material for thermal management.

The Riemerella anatipestifer bacterium is known to cause infectious serositis in ducklings. Moreover, its adherence to the host’s respiratory mucosa is a critical step in pathogenesis. Membrane cofactor protein (MCP; CD46) is a complement regulatory factor on the surface of eukaryotic cell membranes. Bacteria have been found to bind to this protein on host cells. Outer membrane proteins (OMPs) are necessary for adhesion, colonisation, and pathogenicity of Gram-negative bacteria; however, the mechanism by which R. anatipestifer adheres to duck cells remains unclear. In this study, pull-down assays and LC–MS/MS identified eleven OMPs interacting with duck CD46 (dCD46), with OMP71 exhibiting the strongest binding. The ability of an omp71 gene deletion strain to bind dCD46 is weaker than that of the wild-type strain, suggesting that this interaction is important. Further evidence of this interaction was obtained by synthesising OMP71 using an Escherichia coli recombinant protein expression system. Adhesion and invasion assays and protein and antibody blocking assays confirmed that OMP71 promoted the R. anatipestifer YM strain (RA-YM) adhesion to duck embryo fibroblasts (DEFs) by binding to CD46. Tests of the pathogenicity of a Δ omp71 mutant strain of RA-YM on ducks compared to the wild-type parent supported the hypothesis that OMP71 was a key virulence factor of RA-YM. In summary, the finding that R. anatipestifer exploits CD46 to bind to host cells via OMP71 increases our understanding of the molecular mechanism of R. anatipestifer invasion. The finding suggests potential targets for preventing and treating diseases related to R. anatipestifer infection.

Riemerella anatipestifer infection is a critical disease that is a major threat to the poultry industry worldwide. The adhesion and invasion of host cells are key steps in the primary stages of bacterial infection. However, the outer membrane proteins that mediate these events in R. anatipestifer are poorly characterized. In this study, the PorV and PosF proteins, as well as the previously described OMP71 protein, were identified as important mediators of the adhesion and invasion of duck embryo fibroblast (DEF) cells by R. anatipestifer . Affinity chromatography-based surface proteomics was used to screen for adhesion proteins. The surface proteins on DEF cells were labelled with biotin-avidin to enrich for outer membrane proteins of R. anatipestifer, which generated 11 candidate proteins that were tested further. Protein adhesion and blocking assays and polyclonal antiserum inhibition analysis revealed that the PorV, PosF, and OMP71 proteins are adhesion factors. Knockout of porV or posF reduced the adhesion and invasion of R. anatipestifer in DEF cells. Moreover, the pathogenicity of the mutant strains was significantly attenuated, which supports the hypothesis that PorV and PosF are important virulence factors required for the pathogenicity of R. anatipestifer . The PorV protein is a key component of the type IX secretory system and is responsible for transporting effector substrates to the extracellular environment, whereas PosF belongs to the porin superfamily of barrel-shaped transmembrane proteins. This is the first description that PorV is an adhesin involved in host‒microbial interactions, which represents a breakthrough in pathogenicity studies of R. anatipestifer and other members of Flavobacteriaceae .

Polymer-derived SiCN ceramics containing cobalt was prepared with SiCN ceramics as matrix and cobalt nanoparticles as doping phase. Phase composition, Raman analysis, electromagnetic parameters and microwave absorption properties of SiCN ceramics with different cobalt content pyrolyzed at 1100 ℃ and cobalt content of 2 wt% but different pyrolysis temperature were carried out. The microstructures and magnetic properties of SiCN ceramics with cobalt content of 2 wt% and pyrolysis temperature of 900 ℃ were analyzed. The results show that some cobalt particles can react with carbon to form magnetic Co 3 C particles, which is one of the reasons for the magnetism of the sample. The good dielectric property of SiCN ceramics matches the magnetic property, which makes the material have excellent microwave absorption property. When the cobalt content is 2 wt% and the pyrolysis temperature is 900 ℃, the sample has the best microwave absorption performance. The minimum R L reaches − 10.9 at about 15 GHz, and the effective absorption bandwidth ( R L < − 10 dB) is 3.3 GHz with a thickness of 3 mm. When the thickness became 6 mm, the minimum R L of the sample can reach − 11.8 dB and the effective absorption bandwidth ( R L < − 10 dB) is 4.2 GHz, showing the excellent microwave absorption performance of materials we obtained.

Mycoplasma synoviae ( M. synoviae ) infections have become an increasingly serious concern in China because they cause huge economic losses to the poultry industry. Antibiotic treatment is one of control strategies that can be used to contain clinical outbreaks in M. synoviae -free flocks, especially because the bacteria can be transmitted through eggs. To understand M. synoviae infection status in farms of central China and the antibiotic susceptibility of the circulating strains in vivo and in vitro , 485 samples were collected from five provinces from 2019 to 2021. Fifty-two strains were isolated and identified. Determination of the minimum inhibitory concentration (MIC) of eight antibiotics (tylvalosin, tiamulin, tilmicosin, lincomycin, enrofloxacin, chlortetracycline, doxycycline and tylosin) for isolates showed that tylvalosin, doxycycline and tiamulin were effective against 52 clinical isolates (MIC values ≤ 0.0625–0.25 μg/mL, ≤0.0625–1 μg/mL, and 0.25–2 μg/mL, respectively). Tilmicosin, enrofloxacin and lincomycin had high MIC 90 values (>32 μg/mL). An artificial M. synoviae infection model was established in chickens for evaluation of the short-term therapeutic effect of these antibiotics. After 5 days of medication, doxycycline (200 mg/L) showed a superior ability to inhibit M. synoviae compared with other groups, as did tylvalosin (200 mg/L). Furthermore, the therapeutic efficacy of tylvalosin (0.4 μg/mL) on intra-embryo-injected M. synoviae was higher than that of tiamulin at the same dose. A combination of MIC values determined in vitro and therapeutic effects observed in vivo revealed that tylvalosin and doxycycline had the best therapeutic effects. Tylvalosin also showed better inhibitory effects on the vertical transmission of M. synoviae than tiamulin.

Phase instability poses a serious challenge to the commercialization of formamidinium lead iodide (FAPbI 3 )-based solar cells and optoelectronic devices. Here, we combine density functional theory and machine learning molecular dynamics simulations, to investigate the mechanism driving the undesired α-δ phase transition of FAPbI 3 . Prevalent iodine vacancies and interstitials can significantly expedite the structural transition kinetics by inducing robust covalency during transition states. Extrinsically, the detrimental roles of atmospheric moisture and oxygen in degrading the FAPbI 3 perovskite phase are also rationalized. Significantly, we discover the compositional design principles by categorizing that A-site engineering primarily governs thermodynamics, whereas B-site doping can effectively manipulate the kinetics of the phase transition in FAPbI 3 , highlighting lanthanide ions as promising B-site substitutes. A-B mixed doping emerges as an efficient strategy to synergistically stabilize α-FAPbI 3 , as experimentally demonstrated by substantially higher initial optoelectronic characteristics and significantly enhanced phase stability in Cs-Eu doped FAPbI 3 as compared to its Cs-doped counterpart. This study provides scientific guidance for the design and optimization of long-term stable FAPbI 3 -based solar cells and other optoelectronic devices through defect control and synergetic composition engineering. The black phase formamidinium lead iodide perovskite (α-FAPbI3) undergoes an undesired transformation to a non-perovskite δ-phase, rendering it inactive. Here authors show the significant role of inherent iodine defects in accelerating phase transition kinetics and exacerbating α-FAPbI3 instability.

Background Lysyl oxidase-like 4 (LOXL4) has been found to be dysregulated in several human malignancies, including hepatocellular carcinoma (HCC). However, the role of LOXL4 in HCC progression remains largely unclear. In this study, we investigated the clinical significance and biological involvement of LOXL4 in the progression of HCC. Methods LOXL4 expression was measured in HCC tissues and cell lines. Overexpression, shRNA-mediated knockdown, recombinant human LOXL4 (rhLOXL4), and deletion mutants were applied to study the function of LOXL4 in HCC. Exosomes derived from HCC cell lines were assessed for the ability to promote cancer progression in standard assays. The effects of LOXL4 on the FAK/Src pathway were examined by western blotting. Results LOXL4 was commonly upregulated in HCC tissues and predicted a poor prognosis. Elevated LOXL4 was associated with tumor differentiation, vascular invasion, and tumor-node-metastasis (TNM) stage. Overexpression of LOXL4 promoted, whereas knockdown of LOXL4 inhibited cell migration and invasion of HCC in vitro, and overexpressed LOXL4 promoted intrahepatic and pulmonary metastases of HCC in vivo. Most interestingly, we found that HCC-derived exosomes transferred LOXL4 between HCC cells, and intracellular but not extracellular LOXL4 promoted cell migration by activating the FAK/Src pathway dependent on its amine oxidase activity through a hydrogen peroxide-mediated mechanism. In addition, HCC-derived exosomes transferred LOXL4 to human umbilical vein endothelial cells (HUVECs) though a paracrine mechanism to promote angiogenesis. Conclusions Taken together, our data demonstrate a novel function of LOXL4 in tumor metastasis mediated by exosomes through regulation of the FAK/Src pathway and angiogenesis in HCC.

Highlights The zeolitic imidazolate framework functionalized modified layered double hydroxide (ZIF-8@MLDH) composite membranes with superior structural stability and Li+ permeability are prepared by selectively growing ZIF-8 nanoparticles in the framework defects of the MLDH membrane.The tailor-made ZIF-8@MLDH membrane has a large Li+ permeability of up to 1.73 mol m-2 h-1 and a high Li+/Mg2+ selectivity of 31.9, which exceed most of the current 2D lamellar membranes.Two-dimensional (2D) membrane-based ion separation technology has been increasingly explored to address the problem of lithium resource shortage, yet it remains a sound challenge to design 2D membranes of high selectivity and permeability for ion separation applications. Zeolitic imidazolate framework functionalized modified layered double hydroxide (ZIF-8@MLDH) composite membranes with high lithium-ion (Li+) permeability and excellent operational stability were obtained in this work by in situ depositing functional ZIF-8 nanoparticles into the nanopores acting as framework defects in MLDH membranes. The defect-rich framework amplified the permeability of Li+, and the site-selective growth of ZIF-8 in the framework defects bettered its selectivity. Specifically speaking, the ZIF-8@MLDH membranes featured a high permeation rate of Li+ up to 1.73 mol m−2 h−1 and a desirable selectivity of Li+/Mg2+ up to 31.9. Simulations supported that the simultaneously enhanced selectivity and permeability of Li+ are attributed to changes in the type of mass transfer channels and the difference in the dehydration capacity of hydrated metal cations when they pass through nanochannels of ZIF-8. This study will inspire the ongoing research of high-performance 2D membranes through the engineering of defects.

The Luoyang area of the Yellow River Basin, as a typical resource-based city, its special industrial structure and complex geological structure make the ecological and geological environment of the area extremely fragile. In order to realize the sustainable development of the region in this fragile ecological-geological environment, it is necessary to study its Ecological Geological Environmental Carrying Capacity (EGECC) to better serve the regional ecological-geological environment restoration and management work. This study constructs an indicator system encompassing three subsystems: Geological Environment (GE), Social Environment (SE), and Ecological Environment (EE). Based on game theory combination weighting (G1-IEW-GT) and the Normal Cloud model, the EGECC of Luoyang City from 2000 to 2022 was evaluated on a grid scale. Concurrently, a coupled model of geographic detectors and geographically weighted regression was established to recognize the spatial heterogeneity and driving mechanisms of the ecological geological environment system. The findings demonstrate that: (1) The overall EGECC in the Luoyang region of the YRB fluctuates upward, with the eastern area displaying more favorable conditions compared to the western region. (2) Over these twenty-two years, the geological environment system experienced initial deterioration followed by improvement, the ecological environment system remained relatively stable, and social and economic development continuously strengthened. (3) Landform types, elevation, human activity impact index, population density, and geological disaster susceptibility are the main driving elements for the assessment of the ecological geological environment system. Any pair of the 18 variables show varying degrees of enhancement effects on the EGECC. (4) The regression coefficients of the five major driving factors exhibit significant agglomeration characteristics in spatial distribution. Among them, geological disaster susceptibility has a negative driving effect on the EGECC, while landform, human activity impact index, and population density all display bidirectional effects. Overall, this study provides essential guidance for formulating ecological protection and restoration plans for the national territorial space in the Luoyang area of the YRB. Additionally, the evaluation methods established in this study have promotional value and can serve as a reference for the ecological geological spatial management of other resource-based cities.