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Magnesium phosphate bone cement (MPBC) is a bone repair material that has been extensively studied. For better availability of clinical medicine, its degradation rate needs to be effectively controlled. Hydroxypropyl methylcellulose (HPMC) has often been used as a drug carrier for controlled drug release. This property was utilized to influence the release kinetics of MPBC. This work investigated the degradation mechanism of MPBC controlled by HPMC. It was found that MPBC samples with 3 wt. % HPMC had the optimal properties. In this case, the setting time was 11 min and the maximum strength was 63.9 ± 2.5 MPa. The study found HPMC primarily controlled the degradation of MPBC hydration products via the combined actions of gradual diffusion, and release of MPBC hydration products, which subsequently caused the swelling, corrosion, and dissolution of the HPMC skeleton. Besides, the results showed that HPMC‐modified MPBC has good bioactivity, which is beneficial to bone repair. This bioactive HPMC‐modified MPBC showed a controllable degradation rate and proper mechanic properties, which may be applied to bone repair. [ABSTRACT FROM AUTHOR]

BACKGROUND Alginate oligosaccharides (AOS), with various physiological effects, have been widely used in the food, agricultural, and pharmaceutical industries. The biological enzymatic method of preparing AOS, using alginate lyase, has more advantages compared with physical and chemical methods. Cloning and heterologously expressing alginate lyase are therefore very important. RESULTS: A novel alginate lyase, BY17PV7, from Microbulbifer sp. BY17, isolated from Gracilaria, was cloned and expressed in Escherichia coli BL21(DE3). BY17PV7 was about 27 KDa. BY17PV7 showed the greatest activity (150.42 ± 3.32 U/mg) at 43 °C and pH 8.9. It could be activated by Ca2+, Mn2+, Co2+, Fe3+, Na+, and inhibited by Mg2+, Zn2+, Ba2+, Cu2+, sodium dodecyl sulfate (SDS), ethylene diamine tetraacetic acid (EDTA). BY17PV7 had a wide range of substrate specificity and good degradation effects for poly β‐D‐mannuronate (polyM) and poly α‐L‐guluronate (polyG), demonstrating that it is a bifunctional alginate lyase. The kinetic parameters showed that BY17PV7 had a greater affinity for polyG. BY17PV7 released AOS with a degree of polymerization (DP) of 3–4 in an endolytic manner from sodium alginate. Alginate oligosaccharides showed strong antioxidant ability of reducing Fe3+ and scavenging radicals such as hydroxyl, 2,2‐azion‐bia (3‐ethylbenzo‐thiazoline‐6‐sulfonic acid diammonium salt) (ABTS) and 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH). CONCLUSION: A novel bifunctional alginate lyase, BY17PV7, was expressed and characterized in Escherichia coli BL21(DE3). The results were helpful for the analysis of the molecular mechanisms of degrading patterns in the polysaccharide lyase (PL) family. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

2D moiré superlattices offer a versatile platform for manipulating quantum materials, exploiting their spatially varying atomic registry to modify electronic structures, resulting in the emergence of flat electronic minibands, enhanced electronic interactions, and the onset of novel quantum phenomena. Despite extensive investigations into moiré excitons within twisted bilayer moiré superlattices, the interplay between moiré superlattices and optical microcavities remains elusive. Here, a WSe2 homobilayer with a small twist angle positioned on optical microcavities atop a SiO2 (285 nm)/Si substrate is investigated. Utilizing low‐temperature photoluminescence (PL) spectroscopy, it is observed that the twisted homobilayer at the edge of the optical cavity (Edge‐THB) exhibits enhanced localization of moiré excitons and a deeper moiré potential. This behavior is attributed to the combined influence of strain induced by the optical microcavity structure on the moiré superlattice and the amplification of the electromagnetic field. Furthermore, the existence of moiré excitons through a comprehensive analysis, encompassing temperature‐dependent PL spectra, circularly polarized PL spectra, and Landé g‐factor measurements for Edge‐THB is validated. These findings provide valuable insights into the intricate interaction between moiré superlattices and optical microcavities, paving the way for future applications in quantum technologies. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs), which are known as a class of porous coordination polymers, have proven to be of great significance to manifold applications, owing to their fascinating topology, ultrahigh porosity, enormous internal surface area, and the combination of being as rigid as inorganic materials and as flexible as organic materials . In this review, we give a concise history of the development of MOFs as functional materials prior to our entry into this area in 2006, then a summary of our road to participate in and extend the outline of the research in MOFs chemistry, as well as the challenge in further designing applicable functional materials. We describe not only the road of evolution from the past, present, and future of this chemistry, but also the road to finalize a functional material from the desire to the design, synthesis, and postmodification of a MOF. Throughout the review, we particularly emphasize the improvements in the application of MOFs as heterogeneous catalysts, such as employing MOFs as one component for the construction of composites, and their extended scope in tough catalytic reactions. Examples of applications in gas storage and separation, small molecular sensing, and our perspectives for future applications triggered by MOFs, are also introduced. [ABSTRACT FROM AUTHOR]

ABSTRACT [ABSTRACT FROM AUTHOR]

Background: Gliomas are highly refractory intracranial cancers characterized by genetic and transcriptional heterogeneity. However, therapeutic options are limited. In the last years, copper‐induced cell death is becoming a prospective treatment strategy for gliomas and other solid tumors, but copper metabolism‐related genes associated with cancer development remain unclear. Methods: We first collected gene expression data from The Cancer Genome Atlas (TCGA) to identify significantly differentially expressed copper metabolism‐related genes in gliomas. Using these genes, we performed COX regression and Least Absolute Shrinkage and Selection Operator (LASSO) regression to construct the prognostic model. The prognostic value of the model was further validated by CGGA testing set. Subsequently, functional analyses were carried out, including gene set enrichment analysis (GSEA), immune infiltration analysis, and mutation analysis. Finally, the expression levels of these genes were verified by immunohistochemical analysis. Results: The prognostic model consisted of 7 genes: CDK1, LOXL2, LOXL3, NFE2L2, SLC31A1, SUMF1 and FDX1. According to this prognosis model, glioma patients could be split into the high‐risk group or low‐risk group, and the low‐risk group showed significantly better prognostic survival (p < 0.001). Moreover, the high‐risk group had higher levels of immune cell infiltration, immune checkpoint genes expression, and higher tumor mutational burden (TMB), which indicates that they might benefit more from immunotherapy. Finally, we confirmed the expression level of FDX1, SUMF1, and SLC31A1 protein as significantly different in glioblastoma, lower‐grade glioma, and non‐tumor brain tissues by immunohistochemical analysis, and the high expression of FDX1 and SLC31A1 protein was related to poor survival in glioma patients. Conclusions: Our study could contribute to the prognosis prediction and decision‐making in patients with gliomas. [ABSTRACT FROM AUTHOR]

Using solar energy through green and simple artificial photosynthesis systems are considered as a promising way to solve the energy and environmental crisis. However, one of the important primary steps of photosynthesis, i.e., energy transfer, is long being ignored especially in inorganic semiconducting systems due to the small exciton binding energies. Herein, the simultaneous interrogation of the charge transfer and energy transfer steps in a photoexcitation process is proposed by utilizing few‐layered nanosheet‐assembled hierarchical BiOBr nanotubes with rich oxygen vacancies (OVs) as efficient multifunctional photocatalysts. Benefiting from the integrated 1D/2D structure and abundant OV defects, the excitonic effect strikes a delicate balance in the optimized BiOBr photocatalyst, showing not only improved charge carrier separation and transfer but also enhanced exciton generation. As a result, the hierarchical BiOBr nanotubes exhibit high efficiency toward photocatalytic CO2 reduction with an impressive CO evolution rate of 135.6 µmol g−1 h−1 without cocatalyst or photosensitizer. The dominant reactive oxygen species of singlet oxygen (1O2) are discriminated for the first time, which originated from an energy transfer process, with electrophilic character, whereas the minor effect of superoxide anion radical (•O2−) with a nucleophilic rate‐determining step in the photocatalytic aerobic oxidation of sulfides. [ABSTRACT FROM AUTHOR]

HYDRUS‐1D has been extensively applied to the simulation of wettable soil infiltration, but very few studies have explored its applicability to the infiltration of water‐repellent soil (WRS) at different depths. To this end, HYDRUS‐1D was used to simulate water movement of layered soil with a surface repellent thickness of 10 cm. The parameters of the van Genuchten model were calibrated and validated using cumulative infiltration (CI), distance of the wetting front (Zf) and volumetric water content (θv) through five respective treatments. Another 10 tilled scenarios were selected to simulate water movement of tilled WRS. RRMSE (relative root mean square error) and CRM (coefficient of residual mass) were adopted to evaluate simulation accuracy. For the calibration and validation, the RRMSE values ranged from 0.04 to 0.251 and 0.042 to 0.101, respectively, indicating that HYDRUS‐1D could effectively simulate water movement of WRS. Furthermore, for layered treatments, the simulation accuracy of θv, CI and Zf decreased with the increase of the degree of repellency and thickness. The treatments with the repellent thickness of 10 cm had higher simulation accuracy than that with repellent thickness of 5 cm when the top layer had the same WRS. The results revealed HYDRUS‐1D was effective in the simulation of water movement in repellent clay loam with different degrees of repellency and depths. Highlights: The applicability of HYDRUS‐1D to the infiltration of water‐repellent soil (WRS) at different depths was explored.The simulation of different degrees of repellency and depths was first conducted.Simulation accuracy decreased with the increase of degree of repellency and thickness.HYDRUS‐1D was effective in simulating water movement of repellent soil. [ABSTRACT FROM AUTHOR]

Artificial H2O2 photosynthesis by covalent organic frameworks (COFs) photocatalysts is promising for wastewater treatment. The effect of linkage chemistry of COFs as functional basis to photoelectrochemical properties and photocatalysis remains a significant challenge. In this study, three kinds of azoles‐linked COFs including thiazole‐linked TZ‐COF, oxazole‐linked OZ‐COF and imidazole‐linked IZ‐COF were successfully synthesized. More accessible channels of charge transfer were constructed in TZ‐COF via the donor‐π‐acceptor structure between thiazole linkage and pyrene linker, leading to efficient suppression of photoexcited charge recombination. Density functional theory calculations support the experimental studies, demonstrating that the thiazole linkage is more favorable for the formation of *O2 intermediate in H2O2 production than that of the oxazole and imidazole linkages. The real active sites in COFs located at the benzene ring fragment between pyrene unit and azole linkage. [ABSTRACT FROM AUTHOR]

Artificial H2O2 photosynthesis by covalent organic frameworks (COFs) photocatalysts is promising for wastewater treatment. The effect of linkage chemistry of COFs as functional basis to photoelectrochemical properties and photocatalysis remains a significant challenge. In this study, three kinds of azoles‐linked COFs including thiazole‐linked TZ‐COF, oxazole‐linked OZ‐COF and imidazole‐linked IZ‐COF were successfully synthesized. More accessible channels of charge transfer were constructed in TZ‐COF via the donor‐π‐acceptor structure between thiazole linkage and pyrene linker, leading to efficient suppression of photoexcited charge recombination. Density functional theory calculations support the experimental studies, demonstrating that the thiazole linkage is more favorable for the formation of *O2 intermediate in H2O2 production than that of the oxazole and imidazole linkages. The real active sites in COFs located at the benzene ring fragment between pyrene unit and azole linkage. [ABSTRACT FROM AUTHOR]

Review: [59 refs. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) and related derivatives have attracted significant research attention due to their potential applications in a variety of fields. However, it remains challenging to fabricate MOF‐based composites into multidimensional structures, especially to endow them with ordered structures. Here, a facile strategy is developed for the preparation of Pt@ zeolitic imidazolate frameworks (ZIF)‐8/SiO2 composite with 3D‐ordered macroporous (3DOM) structure (denoted as 3DOM‐Pt@ZIF‐8/SiO2) by the in situ self‐templated transformation of Pt/ZnO/SiO2 composite with 3DOM structure (denoted as 3DOM‐Pt/ZnO/SiO2), which is prepared by a nanocasting method with face‐centered cubic (fcc) polystyrene spheres as the template. The sampling analysis at various crystallization times confirms the detailed dissolution–precipitation process from 3DOM‐Pt/ZnO/SiO2 to 3DOM‐Pt@ZIF‐8/SiO2, in which Pt nanoparticles (NPs) are fully encapsulated into the 3DOM framework of ZIF‐8/SiO2 by a continuous ZIF‐8 shell in the surface. Besides, it is found that choosing suitable volume ratio of N,N‐dimethylformamide (DMF):H2O and SiO2 content is crucial to induce the in situ nucleation and growth of continuous ZIF‐8 shell on the 3DOM structure and also to prevent the 3DOM structure from collapsing. Crucially, the obtained 3DOM‐Pt@ZIF‐8/SiO2 shows high size‐selective catalytic properties for the hydrogenation of n‐hexene and cis‐cyclooctene due to the molecular sieve effect of ZIF‐8 shell on the framework. A facile self‐templated strategy is developed for the encapsulation of Pt nanoparticles within zeolitic imidazolate frameworks (ZIF)‐8/SiO2 with 3D‐ordered macroporous (3DOM) structure by in situ transformation of Pt/ZnO/SiO2 with 3DOM structure based on a dissolution–precipitation mechanism. The obtained 3DOM‐Pt@ZIF‐8/SiO2 exhibits steady size‐selective catalytic properties for the hydrogenation of n‐hexene and cis‐cyclooctene. [ABSTRACT FROM AUTHOR]

The surface martensite strengthening of ultra‐fine isotropic porous iron has been performed via carburization and quenching treatment at 950 °C for 30 min. This paper is devoted to investigating the evolution of microstructure and related mechanical behavior of porous iron after carburization treatment. Results indicate that an effective carburization thickness (300 µm) contributes to a substantial improvement in compressive ductility (62%) and surface hardness (219 HV0.025) of carburized porous iron. Further, the quenching treatment after carburization produces the porous iron with an ultra‐fine martensite microstructure on surface layer that makes porous iron attain the highest yield strength (256 MPa) and energy absorption capacity (85 KJ kg−1). The major contribution of this present work is a demonstration that an improvement in mechanical properties of ultra‐fine porous iron can be achieved through the carburization and quenching treatment to control the phase structure on surface. Thus, the surface martensite strengthening is considered as a feasible method to prepare more valuable porous iron based alloys, and to provide them with more promising applications on key structural parts. [ABSTRACT FROM AUTHOR]

Review: 199 refs. [ABSTRACT FROM AUTHOR]