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We have synthesized the orthocarbonate Sr2CO4, in which carbon is tetrahedrally coordinated by four oxygen atoms, at moderately high pressures [20(1) GPa] and high temperatures (≈3500 K) in a diamond anvil cell by reacting a SrCO3 single crystal with SrO powder. We show by synchrotron powder X-ray diffraction, Raman spectroscopy, and density functional thoery calculations that this phase, and hence sp3-hybridized carbon in a CO44- group, can be recovered at ambient conditions. Pterostilbene The C-O bond distances are all of similar lengths [≈1.41(1) Å], and the O-C-O angles deviate from the ideal tetrahedral angle by a few degrees only.Hydroxyapatite (HA) is the main inorganic component of human bones and teeth. It has good biocompatibility and bioactivity, which promotes its good application prospects in the field of bone drug carriers. In this study, tetraethylenepentamine-graphene (rGO-TEPA)/CaCO3HA composite microspheres were prepared via microwave hydrothermal synthesis using rGO-TEPA/CaCO3 solid microspheres as intermediates. Furthermore, the incompletely transformed CaCO3 was removed by soaking in a citric acid buffer to obtain rGO-TEPA/HA hollow composite microspheres. The two types of as-prepared composite microspheres exhibited sea urchin-like structures, large BET surface areas, and good dispersibility. Mouse preosteoblast cells (MC3T3-E1) were used for in vitro cytotoxicity experiments. The in vitro cell viability test showed that the two composite drug carriers exhibited noncytotoxicity. Moreover, the doxorubicin (DOX) loading and releasing investigations revealed that the two types of prepared carriers had mild storage-release behaviors and good pH responsiveness. Hence, these rGO-TEPA/HA hollow microspheres have promising applications as bone drug carriers.Mesenchymal stem/stromal cells (MSCs) evoke great excitement for treating different human diseases due to their ability to home inflamed tissues, suppress inflammation, and promote tissue regeneration. Despite great promises, clinical trial results are disappointing as allotransplantation of MSCs trigger thrombotic activity and are damaged by the complement system, compromising their survival and function. To overcome this, a new strategy is presented by the silencing of tissue factor (TF), a transmembrane protein that mediates procoagulant activity. Novel Pluronic-based micelles are designed with the pendant pyridyl disulfide group, which are used to conjugate TF-targeting siRNA by the thiol-exchange reaction. This nanocarrier design effectively delivered the payload to MSCs resulting in ∼72% TF knockdown (KD) without significant cytotoxicity. Hematological evaluation of MSCs and TF-KD MSCs in an ex vivo human whole blood model revealed a significant reduction in an instant-blood-mediated-inflammatory reaction as evidenced by reduced platelet aggregation (93% of free platelets in the TF-KD group, compared to 22% in untreated bone marrow-derived MSCs) and thrombin-antithrombin complex formation. Effective TF silencing induced higher MSC differentiation in osteogenic and adipogenic media and showed stronger paracrine suppression of proinflammatory cytokines in macrophages and higher stimulation in the presence of endotoxins. Thus, TF silencing can produce functional cells with higher fidelity, efficacy, and functions.Aramid paper has been widely used in high-voltage motors and transformers due to its excellent insulation property and thermal durability. However, the smoothness and chemical inertness of aramid fibers lead to a loose structure (voids) of aramid paper, which limits its potential applications in harsh environments, such as high-frequency and high-voltage circuits. This work reports a simple and efficient method to improve the mechanical and insulation properties of meta-aramid paper via controllable dissolving and regeneration of aramid fibers. To obtain a dense and robust structure, the pristine meta-aramid paper was immersed in a dimethyl sulfoxide/potassium hydroxide (DMSO/KOH) mixture to make aramid fibers swelled and dissolved, followed by regeneration in water vapor, eventually generating densified aramid paper with fewer voids and enhanced insulation and mechanical performance. Optimum conditions resulted in aramid paper with the best comprehensive performance, and the tensile strength, Young's modulus, and electrical breakdown strength of the consolidated aramid paper were 22.85 MPa, 0.72 GPa, and 15.3 kV/mm, respectively, which were significantly higher than those of the pristine aramid paper (12.53 MPa, 0.41 GPa, and 8.36 kV/mm). Meanwhile, such treatment did not cause any chemical structure change, and thus it still retained the excellent thermal resistance (Td > 430 °C) of aramid fibers. This simple method can effectively regulate the surface porosity and the mechanical and breakdown strength of aramid paper, as well as provide a generic method for postprocessing and enhancing aramid paper.In China, the problem of myopia among children and adolescents is prominent, and it is urgent to strengthen the prevention and control. Myopia screening and refractive archives establishment are important basic work for myopia prevention and control. However, at present, myopia screening, refractive archives establishment as well as its management and application are still in the initial stage, and face many problems and challenges. In this paper, the significance and standardization of myopia screening and refractive archives establishment, hierarchical closed-loop management after the screening, as well as the difficulties and prospects are discussed, hoping to provide a reference for orderly promoting myopia prevention and control, reducing the prevalence of myopia among children and adolescents in China and promoting the improvement of vision health.Tumor markers (TM) detection is of great significance in tumor screening, monitoring and treatment intervention, which puts forward higher requirements for its detection quality. TM traceability is very important in the process of reagent production and clinical laboratory testing, which can help improving the reliability and comparability of TM testing. Based on the current principles and classification system of metrology traceability in the world, this paper reviews the quality requirements of reference materials and reference measurement methods related to protein and nucleic acid of TM, as well as the problems existing in the international convention reference measurement procedure and traceability system of TM, so as to provide a new idea for the quality assurance work of TM detection.