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Effective separation of inert gas such as Xe and Kr from used nuclear fuel is significant for maintaining ecological environment safety and recycling nuclear fuel. In this study, Al-CDC and Al-BDC with similar linear ligands were synthesized to reveal the influence of ligand regulation on Xe separation under different pressure conditions. The results displayed that the adsorption capacity of Al-BDC for Xe could reach 2.66 mmol g-1 under normal pressure, which is 1.11 times higher than that of Al-CDC, depending on its higher specific surface area and bigger pore volume. On the contrary, the Xe adsorption capacity of Al-CDC with the feature of narrow micropore structure and saturated C-H or oxygen-containing functional groups reached 1.44 mmol g−1 at 0.1 bar, which was 2.82 times higher than that of Al-BDC, resulting in a remarkable difference in Xe working capacity between Al-CDC (0.43 mmol g−1) and Al-BDC (0.073 mmol g−1) through dynamic breakthrough experiments. Meanwhile, the Henry's selectivity of Al-CDC for Xe/Kr and Xe/N 2 was up to 13.97 and 110.31, Compared with most porous adsorbents in previous reports, Al-CDC exhibits both high adsorption capacity and high selectivity. Innovatively, we analyzed the advantage in capacity and selectivity by the perspective of ligands, and the calculation results of the complete cell also proved that the saturated C-H group and benzene ring center on cyclohexane are the main adsorption sites of Al-CDC and Al-BDC for Xe, respectively. Therefore, a higher polar ligand in Al-CDC could lead to strong static binding energy and single cell binding energy which attribute to a high selective Xe adsorption. These results revealed the key structural characteristics for selective Xe adsorption under different pressure conditions, providing valuable suggestions for the design of separation materials from spent fuel. [Display omitted] ● Xe selective adsorption mechanism is proposed via experimental and quantum analyses. ● Higher specific surface area promotes Xe adsorption at normal pressure. ● Narrow channel is crucial to improve the London force effect on Xe at low pressure. ● Saturated C-H groups and high polarity profitably enhance Debye interactions for Xe. ● Carboxyl group and aromatic ring are attractive to Xe for CDC and BDC, respectively. [ABSTRACT FROM AUTHOR]

Background. Bone cement spacers are widely used in two-stage revision surgeries for periprosthetic joint infection (PJI) after total knee arthroplasty. Current spacer design results in insufficient release of drugs; therefore, current spacers have low efficacy. In this study, we explored a set of alternative articular spacer using 3D printing technology. This novel spacer will increase effectiveness of revision surgery for PJI. Methods. The spacer was designed using CAD software and constructed on site using 3D-printed silicone mold during debridement surgery. We carried out a retrospective study among patients undergoing treatment using traditional static and new articular spacers. Infection control rate, bone loss, difficulty of revision surgery, knee joint range of motion, function evaluation, and subjective satisfaction of the patients in the two groups were compared. Results. Forty-two patients undergoing knee revision surgery between Jan 2014 and Nov 2019 were included in this study. Twenty-two patients were treated with static antibiotic cement spacers, whereas the other twenty patients were with treated with 3D printing-assisted antibiotic loaded articulating spacers. Patients in the articular group showed significantly lower bone loss on the femur site and tibial site compared with patients in the static group. In addition, patients in the articular group showed significantly less operation time, intraoperative blood loss, and improved knee function and patient overall satisfaction compared with patients in the static group. Conclusions. The 3D printing-assisted articular spacer provides satisfactory range of motion during the interim period, prevents bone loss, facilitates second-stage reimplantation and postoperative rehabilitation, and results in low reinfection and complication rates. [ABSTRACT FROM AUTHOR]

Background. Bone cement spacers are widely used in two-stage revision surgeries for periprosthetic joint infection (PJI) after total knee arthroplasty. Current spacer design results in insufficient release of drugs; therefore, current spacers have low efficacy. In this study, we explored a set of alternative articular spacer using 3D printing technology. This novel spacer will increase effectiveness of revision surgery for PJI. Methods. The spacer was designed using CAD software and constructed on site using 3D-printed silicone mold during debridement surgery. We carried out a retrospective study among patients undergoing treatment using traditional static and new articular spacers. Infection control rate, bone loss, difficulty of revision surgery, knee joint range of motion, function evaluation, and subjective satisfaction of the patients in the two groups were compared. Results. Forty-two patients undergoing knee revision surgery between Jan 2014 and Nov 2019 were included in this study. Twenty-two patients were treated with static antibiotic cement spacers, whereas the other twenty patients were with treated with 3D printing-assisted antibiotic loaded articulating spacers. Patients in the articular group showed significantly lower bone loss on the femur site and tibial site compared with patients in the static group. In addition, patients in the articular group showed significantly less operation time, intraoperative blood loss, and improved knee function and patient overall satisfaction compared with patients in the static group. Conclusions. The 3D printing-assisted articular spacer provides satisfactory range of motion during the interim period, prevents bone loss, facilitates second-stage reimplantation and postoperative rehabilitation, and results in low reinfection and complication rates. [ABSTRACT FROM AUTHOR]

Background: The complicated hyperglycaemic and chronic inflammation of diabetic wounds in orthopaedic surgery leads to dysregulated immune cell function and potential infection risk. Immune interventions in diabetic wounds face a possible contradiction between simultaneous establishment of the pro-inflammatory microenvironment in response to potential bacterial invasion and the anti-inflammatory microenvironment required for tissue repair. To study this contradiction and accelerate diabetic-wound healing, we developed a photocurable methacryloxylated silk fibroin hydrogel (Sil-MA) system, co-encapsulated with metformin-loaded mesoporous silica microspheres (MET@MSNs) and silver nanoparticles (Ag NPs). Results: The hydrogel system (M@M–Ag–Sil-MA) enhanced diabetic-wound healing via spatiotemporal immunomodulation. Sil-MA imparts a hydrogel system with rapid in situ Ultra-Violet-photocurable capability and allows preliminary controlled release of Ag NPs, which can inhibit bacterial aggregation and create a stable, sterile microenvironment. The results confirmed the involvement of Met in the immunomodulatory effects following spatiotemporal dual-controlled release via the mesoporous silica and Sil-MA. Hysteresis-released from Met shifts the M1 phenotype of macrophages in regions of diabetic trauma to an anti-inflammatory M2 phenotype. Simultaneously, the M@M–Ag–Sil-MA system inhibited the formation of neutrophil extracellular traps (NETs) and decreased the release of neutrophil elastase, myeloperoxidase, and NETs-induced pro-inflammatory factors. As a result of modulating the immune microenvironmental, the M@M–Ag–Sil-MA system promoted fibroblast migration and endothelial cell angiogenesis in vivo, with verification of enhanced diabetic-wound healing accompanied with the spatiotemporal immunoregulation of macrophages and NETs in a diabetic mouse model. Conclusions: Our findings demonstrated that the M@M–Ag–Sil-MA hydrogel system resolved the immune contradiction in diabetic wounds through spatiotemporal immunomodulation of macrophages and NETs, suggesting its potential as a promising engineered nano-dressing for the treatment of diabetic wounds in orthopaedic surgery. [ABSTRACT FROM AUTHOR]

Robust bacterial metabolism and the immunosuppression on peripheral immune cells cause biofilm‐associated infections (BAIs) extremely refractory to be eradicated via antibiotics alone. Herein, hierarchical mesoporous UiO‐66 metal–organic framework is decorated with selenite, polypyrrole, and macrophage membrane (MM) to develop a biomimetic nanosphere (USPM). Following the recruitment of USPM to the biofilm microenvironment (BME) via the pathogen‐targeting ability derived from MM. The BME‐responsive USPM can precisely release selenite to penetrate the loosened biofilm in synergy with near‐infrared‐induced mild photothermal therapy (mPTT). Selenite can quickly react with reducing substances to generate hydrogen selenide (H2Se) inside the biofilm. H2Se can competitively inhibit bacterial metabolic processes and disrupt biofilm metabolic homeostasis by cascade amplification effects. Furthermore, H2Se inside the biofilm further sensitizes photothermia to exert a precise local photothermal effect. Outside the biofilm, USPM can simultaneously promote the phagocytosis and autophagy of macrophages to kill and decompose the phagocytosed bacteria. Finally, the well‐decomposed bacterial antigens in macrophages can be presented to antigen‐presenting cells to arouse adaptive immune responses and enhance anti‐biofilm effectiveness further. Such powerful mPTT‐enhanced bacterial metabolic disruption and macrophagic autophagy‐promoted adaptive immune activation suggest an alternative therapeutic strategy to cure refractory BAIs. [ABSTRACT FROM AUTHOR]

Efficient CH 4 /N 2 separation from unconventional natural gas is vital for both energy recycling and climate change control. Figuring out the reason for the disparity between ligands in the framework and CH 4 is the crucial problem for developing adsorbents in PSA progress. In this study, a series of eco-friendly Al-based MOFs, including Al-CDC, Al-BDC, CAU-10, and MIL-160, were synthesized to investigate the influence of ligands on CH 4 separation through experimental and theoretical analyses. The hydrothermal stability and water affinity of synthetic MOFs were explored through experimental characterization. The active adsorption sites and adsorption mechanisms were investigated via quantum calculation. The results manifested that the interactions between CH 4 and MOFs materials were affected by the synergetic effects of pore structure and ligand polarities, and the disparities of ligands within MOFs determined the separation efficiency of CH 4. Especially, the CH 4 separation performance of Al-CDC with high sorbent selection (68.56), moderate isosteric adsorption heat for CH 4 (26.3 kJ/mol), and low water affinity (0.1 g/g at 40% RH) was superior to most porous adsorbents, which was attributed to its nanosheet structure, proper polarity, reduced local steric hindrance, and extra functional groups. The analysis of active adsorption sites indicated that hydrophilic carboxyl groups and hydrophobic aromatic ring were the dominant CH 4 adsorption sites for liner ligands and bent ligands, respectively. The methylene groups with saturated C–H bonds enhanced the wdV interaction between ligands and CH 4 , resulting in the highest binding energy of CH 4 for Al-CDC. The results provided valuable guidance for the design and optimization of high-performance adsorbents for CH 4 separation from unconventional natural gas. [Display omitted] • Experimental and DFT data were combined to explore interactions for CH 4 separation. • Synergetic effects of pore structure and ligand polarity determined CH 4 separation. • Al-CDC possessed high S SP and moderate Q s t − C H 4 , preceding most porous adsorbents. • CH 4 preferred carboxyl groups for liner ligand and aromatic rings for bent ligand. [ABSTRACT FROM AUTHOR]

A comprehensive investigation was conducted to explore the adsorption behaviors of CH 4 over N 2 on ultra-microporous Al/Zr-FDCA frameworks, which were synthesized specifically using the eco-friendly and bio-sourced 2,5-furandicarboxylic acid (FDCA). Characterization results revealed that both Al-FDCA and Zr-FDCA exhibited similar specific surface area and surface groups, leading to comparable methane uptake per-unit mass at atmospheric pressure. However, the presence of Zr nodes generated ultra-micropores around 0.43 nm in size, leading to a pronounced affinity for CH 4. Zr-FDCA demonstrated a higher CH 4 /N 2 selectivity (8.90) calculated from the isotherms compared to Al-FDCA (3.86). Furthermore, breakthrough experiments indicated that under the same dynamic conditions, Zr-FDCA exhibited 1.5 times higher CH 4 uptake per unit volume and 2.5 times higher CH 4 /N 2 selectivity when compared to Al-FDCA. Initially, a four-step VPSA process was simulated to investigate the separation of CH 4 /N 2 mixture, in which the effects of feed-gas flow rate, adsorption time, adsorption pressure, and desorption pressure in VPSA cycle were extensively evaluated to enhance the purity and recovery of methane. Subsequently, a six-step process was employed for further optimization, achieving a purity of 95.9 % and a recovery of 99.1 %. The obtained results demonstrated the reliability of the established model and highlighted the significant potential of Zr-FDCA for CH 4 /N 2 separation. [Display omitted] • Ultra-microporous Al/Zr-FDCA MOFs with bio-sourced ligand synthesized for nature gas upgrading. • Zr-FDCA exhibits an excellent CH 4 /N 2 selectivity of 9.0, as 2.3 times as that of Al-FDCA at 298 K and 1 bar. • Dynamic CH 4 uptake and selectivity of per unit volume Zr-FDCA are 1.5 and 2.5 times as those of Al-FDCA. • Zr nodes had a significant impact on the pore size distribution and adsorption strength with methane. • CH 4 recovery and purity of the optimized six-step VPSA cycle reach 95.9 % and 99.1 % for Zr-FDCA. [ABSTRACT FROM AUTHOR]

Implant-associated infections (IAIs) pose a significant threat to orthopedic surgeries. Bacteria colonizing the surface of implants disrupt bone formation-related cells and interfere with the osteoimmune system, resulting in an impaired immune microenvironment and osteogenesis disorders. Inspired by nature, a zeolitic imidazolate framework (ZIF)-sealed smart drug delivery system on Ti substrates (ZSTG) was developed for the "natural-artificial dual-enzyme intervention (NADEI)" strategy to address these challenges. The subtle sealing design of ZIF-8 on the TiO 2 nanotubes ensured glucose oxidase (GOx) activity and prevented its premature leakage. In the acidic infection microenvironment, the degradation of ZIF-8 triggered the rapid release of GOx, which converted glucose into H 2 O 2 for disinfection. The Zn2+ released from degraded ZIF-8, as a DNase mimic, can hydrolyze extracellular DNA, which further enhances H 2 O 2 -induced disinfection and prevents biofilm formation. Importantly, Zn2+-mediated M2 macrophage polarization significantly improved the impaired osteoimmune microenvironment, accelerating bone repair. Transcriptomics revealed that ZSTG effectively suppressed the inflammatory cascade induced by lipopolysaccharide while promoting cell proliferation, homeostasis maintenance, and bone repair. In vitro and in vivo results confirmed the superior anti-infective, osteoimmunomodulatory, and osteointegrative capacities of the ZSTG-mediated NADEI strategy. Overall, this smart bionic platform has significant potential for future clinical applications to treat IAIs. [ABSTRACT FROM AUTHOR]

Summary: With the increasing challenge of energy, resource, and environment, it is highly desired to develop renewable energy and corresponding efficient energy storage technologies basing on reproducible materials. Recently, using biomass and biotechnology to prepare electrode material for energy storage devices is gaining growing attention. Here, we use biomass, celery, as a material source and developed a new way to prepare highly qualified graphitized porous carbon. Besides, instead of direct carbonization, the celery is first freeze‐dried to protect the original elements and structure of biomass. Furthermore, to sculpture more nanoscale pores in the produced material, the following carbonization process is also greatly modified by investigating proper carbonization temperature and time. Therefore, the interconnected hierarchical porous structure can be formed based on the protected original pores with size of micrometers and the newly formed pores with size of nanometers. The resulted interconnected hierarchical porous carbon is used to prepare supercapacitor electrode and exhibit excellent energy storage properties. Without any extra activating or doping process, the specific capacitance of the resulted electrode reached 350.0 F g−1 at 1 A g−1, which is 5.28 times of that of directly carbonized material. And the power density reached 8.0 kW kg−1 with the energy density maintaining 16.3 Wh kg−1. [ABSTRACT FROM AUTHOR]