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In this work, two zinc‐based metal–organic frameworks (Zn‐MOFs) with different morphologies were successfully produced by the surfactant‐mediated synthesis method. They were grown on the Polytetrafluoroethylene (PTFE)/polydopamine (PDA) to prepare PTFE/PDA/Zn‐MOFs fiber fabrics. Then the epoxy resin (EP) matrix was poured onto fabrics to prepare EP/PTFE/PDA/Zn‐MOF. PTFE was modified by introducing a PDA adhesion layer, which can provide absorption sites for Zn‐MOFs growth and improve the bonding strength with EP. The microscopic morphologies and structures of the PTFE and modified PTFE were studied. Compared with pure EP, the friction coefficient and specific wear rate of the EP/PTFE/PDA/ZnMOF2 composite were reduced by 67% and 91%, and the EP/PTFE/PDA/ZnMOF1 composite were reduced by 55% and 88%, respectively, which were due to the loading of ZnMOF2 onto the PTFE surface, improving the interfacial bonding between the PTFE and EP matrix and can prevent the PTFE fabric from coming out of the EP matrix. ZnMOF2 also presents its structural advantage: the unique thin layer structure plays a vital role in friction and wear reduction. [ABSTRACT FROM AUTHOR]

Antibody‐mediated rejection (AMR) is the commonest cause of failure of a pig graft after transplantation into an immunosuppressed nonhuman primate (NHP). The incidence of AMR compared to acute cellular rejection is much higher in xenotransplantation (46% vs. 7%) than in allotransplantation (3% vs. 63%) in NHPs. Although AMR in an allograft can often be reversed, to our knowledge there is no report of its successful reversal in a pig xenograft. As there is less experience in preventing or reversing AMR in models of xenotransplantation, the results of studies in patients with allografts provide more information. These include (i) depletion or neutralization of serum anti‐donor antibodies, (ii) inhibition of complement activation, (iii) therapies targeting B or plasma cells, and (iv) anti‐inflammatory therapy. Depletion or neutralization of anti‐pig antibody, for example, by plasmapheresis, is effective in depleting antibodies, but they recover within days. IgG‐degrading enzymes do not deplete IgM. Despite the expression of human complement‐regulatory proteins on the pig graft, inhibition of systemic complement activation may be necessary, particularly if AMR is to be reversed. Potential therapies include (i) inhibition of complement activation (e.g., by IVIg, C1 INH, or an anti‐C5 antibody), but some complement inhibitors are not effective in NHPs, for example, eculizumab. Possible B cell‐targeted therapies include (i) B cell depletion, (ii) plasma cell depletion, (iii) modulation of B cell activation, and (iv) enhancing the generation of regulatory B and/or T cells. Among anti‐inflammatory agents, anti‐IL6R mAb and TNF blockers are increasingly being tested in xenotransplantation models, but with no definitive evidence that they reverse AMR. Increasing attention should be directed toward testing combinations of the above therapies. We suggest that treatment with a systemic complement inhibitor is likely to be most effective, possibly combined with anti‐inflammatory agents (if these are not already being administered). Ultimately, it may require further genetic engineering of the organ‐source pig to resolve the problem entirely, for example, knockout or knockdown of SLA, and/or expression of PD‐L1, HLA E, and/or HLA‐G. [ABSTRACT FROM AUTHOR]

In tribology, a considerable number of computational and experimental approaches to understand the interfacial characteristics of material surfaces in motion and tribological behaviors of materials have been considered to date. Despite being useful in providing important insights on the tribological properties of a system, at different length scales, a vast amount of data generated from these state-of-the-art techniques remains underutilized due to lack of analysis methods or limitations of existing analysis techniques. In principle, this data can be used to address intractable tribological problems including structure–property relationships in tribological systems and efficient lubricant design in a cost and time effective manner with the aid of machine learning. Specifically, data-driven machine learning methods have shown potential in unraveling complicated processes through the development of structure–property/functionality relationships based on the collected data. For example, neural networks are incredibly effective in modeling non-linear correlations and identifying primary hidden patterns associated with these phenomena. Here we present several exemplary studies that have demonstrated the proficiency of machine learning in understanding these critical factors. A successful implementation of neural networks, supervised, and stochastic learning approaches in identifying structure–property relationships have shed light on how machine learning may be used in certain tribological applications. Moreover, ranging from the design of lubricants, composites, and experimental processes to studying fretting wear and frictional mechanism, machine learning has been embraced either independently or integrated with optimization algorithms by scientists to study tribology. Accordingly, this review aims at providing a perspective on the recent advances in the applications of machine learning in tribology. The review on referenced simulation approaches and subsequent applications of machine learning in experimental and computational tribology shall motivate researchers to introduce the revolutionary approach of machine learning in efficiently studying tribology. [ABSTRACT FROM AUTHOR]

Water‐based anticorrosive coatings have poor water resistance, which easily lead to coating deterioration and metal corrosion. In order to improve the anticorrosion performance of waterborne coating, herein, the polytetrafluoroethylene/dimethyl siloxane/epoxy resin (PTFE/PDMS/EP) hydrophobic anticorrosive coating was prepared by layer‐by‐layer construction. The spatial structure and microscopic morphology of the hydrophobic coating were analyzed by XRD, FTIR, and SEM. The hydrophobicity and corrosion resistance of the composite coating were analyzed by hydrophobicity test, electrochemical polarization curve, hydrophobicity and corrosion resistance test of the mixed layer, Tafel polarization curves, and AC impedance spectrum. The results showed that the water contact angle of PTFE/PDMS/EP coating reached 141° and the protection efficiency of PTFE/PDMS/EP coating was 98.62%. After soaking for 7 days, the corrosion process still stays at the initial stage, which was mainly due to the good sealing and barrier properties and high anticorrosion efficiency of PTFE/PDMS/EP coating. The coating has high corrosion protection efficiency and long service life, which is of great significance to metal corrosion protection in harsh marine environments. [ABSTRACT FROM AUTHOR]

Particulate matter 2.5 (PM 2.5.) pollution is a serious threat to human health. In this paper, we firstly used electrospraying technology to fabricate composite polytetrafluoroethylene (PTFE)/expanded graphite (EG) coated spun‐bond polypropylene (PP) microporous filters that show tremendous potential for its use as an effective PM 2.5. capture medium. The surface morphology, the surface area, the surficial chemical structure, the hydrophobicity, the antifouling ability, the mechanical property, the air permeability, and the filtration efficiency (FE) of the prepared composite PTFE/EG coated microporous filters were investigated. It is found that with the increase of EG content, the surface area of the filter tended to increase, and the pore size decreased correspondingly. Physical adhesion between the PTFE or PTFE/EG and the PP fabric is found. The composite PTFE/EG coated spun‐bond PP microporous filter exhibits an excellent hydrophobicity and antifouling ability. Compared with the original spun bond PP, the FE of the composite PTFE/EG coated spun bond PP microporous filter for PM 2.5. is significantly increased from 52.18% to 85.00%, and the quality factor (QF) increases from 0.0238 to 0.0431. These results indicate that the composite PTFE/EG coated spun‐bond PP microporous filter is an excellent material for PM 2.5. capture. [ABSTRACT FROM AUTHOR]