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[Display omitted] • GHPSM displayed enhanced accumulation and controlled drug release in OA cartilage site. • GHPSM delayed OA progression by reshaping OA microenvironment via multi-channel. • The progressions of early OA disease after treatments were tracked by fluorescence/MR imaging. Osteoarthritis (OA) is a degenerative joint disease of the knee joint, suffering from the limited therapeutic effect and serious side effects. Unfortunately, there are currently rarely available materials to fundamentally delay and monitor OA progression. The OA microenvironment, including excessive inflammation, matrix metalloproteinases (MMPs), oxidative stress, and reactive oxygen species (ROS), play a crucial role in the pathogenesis of OA. Utilizing and remodeling OA microenvironment may be an effective strategy for the diagnosis and treatment of OA. This work developed an intelligent responsive nanoprobe, Gd-HMPB@SMT@MMP (GHPSM) by encapsulating S-methylisothiourea (SMT) loaded mesoporous Prussian Blue (Gd-HMPB) with Tetramethyl Rhodamine (TAMRA) labeled MMP-13 peptide (MMP-13-TAMRA) for this aim. GHPSM displayed enhanced accumulation in OA cartilage site due to the decrease in the content of negatively charged aminoglycans (GAGs) in early degenerative articular cartilage and activated fluorescence signal as well as SMT controlled release due to the cleavage of MMP-13-TAMRA from GHPSM by overexpressed MMP-13 matrix protease in OA microenvironment. Furthermore, integrating the function of SMT and PB nanozyme, GHPSM reshaped the OA microenvironment by reducing the release of ROS and inflammatory factors (TNF-α, IL-6, iNOS), increasing the expression of intermediate structural proteins (COL2 and Aggrescan), thereby reducing cartilage degradation and chondrocyte apoptosis, ultimately delaying the development of OA. The progressions of early OA disease after different treatments were successfully tracked based on fluorescence/MR imaging with X-ray imaging of knee joint for comparation. These findings highlight the potentials of GHPSM in monitoring the status of cartilage in real-time and delay OA progression by reshaping the OA microenvironment, providing novel ideas for future research in OA diagnosis and treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe(II) can provide electrons to promote the reduction of nitrite. • Fe(III) supported the growth and metabolism of P. JM-7 as an electron acceptor. • The higher growth and proliferation of P. JM-7 in iron-containing fillers. • The morphology of phosphate was similar to bidentate-bonded Fe–PO 4 complexes. • Administering Fe(II)/Fe(III) should consider their nucleation and crystallization. The interdependence between iron and nitrogen in the environment is of utmost importance, and this study has explored the intricate relationship between denitrification and iron valence cycling using Pseudomonas sp. strain JM-7 (P. JM-7) as a model bacteria. Our research demonstrated that P. JM-7 had the ability to effectuate electron transfer from the periplasmic space to electron acceptors, such as nitrate, via Cytochrome c -proteins (c-Cyts). We found that iron valence state transformations with Fe(II)/Fe(III) promoted P. JM-7′s denitrification of nitrate coupled to yeast extract powder (YEP) oxidation. Denitrification rates depended on temperature (>21 °C) and pH (6–9). During logarithmic growth, 5 g/L YEP enabled 350 mg/L nitrate removal, increasing to 1650 mg/L in stable growth. Addition of 4 mM Fe(II)/Fe(III) increased denitrification to 500 mg/L during logarithmic growth. The dynamic test results displayed that compared to the SiO 2 filler control group, iron-containing fillers could facilitate P. JM-7 to reduce 100 mg/L nitrate with 50 mg/L YEP electrons, corresponding to 6 times the maximum electron transfer efficiency in the static test. Overall, iron redox cycling significantly enhanced P. JM-7 denitrification, imparting insights into iron–nitrogen interactions. In summary, our research imparts valuable insights into the nexus between iron and nitrogen in the environment, highlighting the potential application of P. JM-7 in environmental engineering. Our findings indicate that P. JM-7 exhibits a significant denitrification capability, and further research is recommended to investigate its ability to remove phosphorus and promote sustainable environmental remediation practices. [ABSTRACT FROM AUTHOR]

• Z-scheme ZIS/BTO heterojunction with piezoelectric effect was synthesized. • ZIS/BTO heterojunction promoted charge separation and prolonged carrier lifetime. • Charge transfer mechanism was investigated by DFT calculations and experiments. • ZIS/BTO heterojunction exhibited significant CO yield under light and ultrasound. Converting CO 2 into high-value-added chemicals by artificial photosynthesis technology effectively solves environmental problems and energy shortages. Nevertheless, it remains challenging to improve CO 2 conversion rates due to low photo-utilization and rapid electron-hole recombination. In this study, we successfully synthesized direct Z-scheme ZnIn 2 S 4 /BaTiO 3 heterojunction structure by a hydrothermal method. Specifically, compared with previous studies of various heterojunction catalysts, ZnIn 2 S 4 /BaTiO 3 heterojunction structure achieved a remarkably high yield of 105.89 μmol g-1 h-1, increasing 2.55 and 3.62-fold over the individual performance of ZnIn 2 S 4 and BaTiO 3 , respectively. Our investigation of photocatalytic mechanism suggest that the improved photocatalytic CO 2 reduction performance can be attributed to the synergistic effects of the piezoelectric effect and Z-scheme electron transfer mechanism. These effects can synergistically enhance space charge separation and retain photogenerated electrons, thereby facilitating a more efficient CO 2 reduction process. Consequently, this innovative piezoelectric effect-assisted Z-scheme heterojunction demonstrates immense potential to offer a novel strategy for addressing CO 2 reduction challenges and advancing sustainable energy development. [ABSTRACT FROM AUTHOR]