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Although the use of bioactive ions and proteins are crucial for bone defect repair, delivering them in a stable and controlled manner remains challenging. To achieve controlled delivery of osteogenic active factor, we developed a novel double network (DN) hydrogel capable of co-delivering Mg2+ ions and BMP2 in a controlled localized manner. This DN hydrogel was composed of poly (acrylamide) and chitosan, in which the poly (acrylamide) was cross-linked via covalent bond and the chitosan was grafted using bisphosphonate (BP) to form metal coordination bonds with Mg2+ ions. Due to this dynamic dissociation and re-association of the "BP-Mg2+" coordination bond, it was possible to deliver Mg2+ ions in a stable and controlled manner. Additionally, the obtained DN hydrogel exhibited an effective tensile strength (0.62 MPa), perfect stretchability (973% fracture strain), and good creep and recovery properties due to the dynamic cross-linking effect of "BP-Mg2+". Additionally, the hydrogel could synergistically promote the proliferation and differentiation of mouse embryo osteoblast precursor cells (MC3T3-E1 cells) in vitro via the BMP2/Wnt pathway. In the skull defect rat model, this positive delivery government of Mg2+ ions and BMP2 synergistically accelerated bone regeneration. In conclusion, this dynamic cross-linked hydrogel containing Mg2+ ions established a new platform for the sustained release of osteogenesis factor and accelerated the bone regeneration process. • The hydrogel was cross-linked by covalent and ions dynamic coordination bond. • The dissociation and re-association of the coordination bond enables Mg2+ ions to be delivered in controlled manner. • The sulfhydryl group of BMP2 protein can bind with Mg2+ ions to form the "S-Mg2+-S" coordination bond. • The cross-linked hydrogel became degraded to adapt new bone regeneration as the Mg2+ ions released outside. [ABSTRACT FROM AUTHOR]

The remote and non-invasive optical thermometer exploiting fluorescence intensity ratio technology is of great importance in various intelligent optoelectronic sensors. Dual-emitting YNbO 4 :Bi3+, Eu3+ phosphor is synthesized and investigated for the development of temperature sensing materials. The phosphor excited at 318 nm shows a blue broad band emission and several red sharp peaks. The value of Bi3+→Eu3+ energy transfer can reach 98.2% when Eu3+ doping content is 0.14. Benefiting from diverse thermal response behaviors due to Bi3+ and Eu3+ ions completely different electronic configurations, a dual-emitting optical thermometer is designed. The maximum values of absolute and relative sensitivities are as high as 2.51% K−1 at 473 K and 1.43% K−1 at 423 K, respectively. The thermochromic phosphor possesses a great chromaticity shift (ΔE = 317×10−3) with temperature. Based on superior color discriminability, visual colorimetry temperature measurement relied on thermal characteristic is proposed. All the results demonstrate that YNbO 4 :0.01Bi3+, 0.005Eu3+ phosphor as a sensitive and reliable optical thermometer has great potentials in temperature measurement. [ABSTRACT FROM AUTHOR]

• Metabolic alteration of articular cartilage is associated with pathogenesis of Osteoarthritis (OA). This study aims to identify the metabolism-related genes, corresponding transcription factors, and relevant pathways. We established a comprehensive network integrated with transcription factors, metabolism-related genes, and hallmarks. Metabolic alteration of articular cartilage is associated with the pathogenesis of Osteoarthritis (OA). This study aims to identify the metabolism-related genes, corresponding transcription factors (TFs), and relevant pathways. Overall, RNA sequencing profiles of articular cartilage were collected from the GEO database. Metabolism-related genes and OA-related hallmarks were collected from the MSigDB v7.1. Differential expression analysis, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, and Gene Set Variation Analysis (GSVA) were conducted to identify pathways or hallmarks that were related to the pathogenesis of OA. The Pearson correlation analysis was used to establish the regulatory network among transcription factors, metabolism-related genes, and hallmarks. To further confirm the regulation of the identified transcription factors, Chromatin Immunoprecipitation-sequencing (ChIP-seq) was conducted, and single-cell sequencing was used to locate the cell clusters. Connectivity Map (CM) analysis were also conducted to identify the potential specific bioactive small molecules targeting the metabolic alteration of osteoarthritis. scTPA database was used to detect activated signaling pathways. Collectively, a total of 74 and 38 differentially expressed metabolism-related genes and TFs were retrieved. Skeletal system development, extracellular matrix, and cell adhesion molecule binding were important pathways in GO analysis. Human papillomavirus infection, PI3K-Akt signaling pathway, and Human T-cell leukemia virus 1 infection were the top 3 pathways in KEGG. 7 and 12 hallmarks were down- and up-regulated in GSVA, respectively. Ten bioactive small molecules may be potential treatments of OA by regulating the metabolism of articular cartilage. ChIP-seq analysis showed high relativity between transcription factors and their target genes. Furthermore, single-cell sequencing confirms the high expression of identified transcription factors in chondrocytes. To conclude, we established a comprehensive network integrated with transcription factors, metabolism-related genes, and hallmarks. [ABSTRACT FROM AUTHOR]

The healing of critical-sized bone defects is a major challenge in the field of bone tissue engineering. Gelatin-related hydrogels have emerged as a potential solution due to their desirable properties. However, their limited osteogenic, mechanical, and reactive oxygen species (ROS)-scavenging capabilities have hindered their clinical application. To overcome this issue, we developed a biofunctional gelatin-Mxene nanocomposite hydrogel. Firstly, we prepared two-dimensional (2D) Ti 3 C 2 MXene nanosheets using a layer delamination method. Secondly, these nanosheets were incorporated into a transglutaminase (TG) enzyme-containing gallic acid-imbedded gelatin (GGA) pre-gel solution to create an injectable GGA-MXene (GM) nanocomposite hydrogel. The GM hydrogels exhibited superior compressive strength (44–75.6 kPa) and modulus (24–44.5 kPa) compared to the GGA hydrogels. Additionally, the GM hydrogel demonstrated the ability to scavenge reactive oxygen species (OH- and DPPH radicals), protecting MC3T3-E1 cells from oxidative stress. GM hydrogels were non-toxic to MC3T3-E1 cells, increased alkaline phosphatase secretion, calcium nodule formation, and upregulated osteogenic gene expressions (ALP, OCN, and RUNX2). The GM400 hydrogel was implanted in critical-sized calvarial defects in rats. Remarkably, it exhibited significant potential for promoting new bone formation. These findings indicated that GM hydrogel could be a viable candidate for future clinical applications in the treatment of critical-sized bone defects. • The successful incorporation of MXene nanosheets into a GGA hydrogel • The hydrogel was formed with a mild, simple, and controllable enzymatic method. • Improved compressive strength and modulus • The hydrogel presented in vitro osteogenic and ROS-scavenging properties • Ability to promote rat critical-sized calvarial defects repair. [ABSTRACT FROM AUTHOR]

• A macrophage membrane coated curcumin-loaded biomimetic nanosponge system was designed for osteoarthritis alleviation. • This system can alleviate the progression of osteoarthritis by synergistically suppressing inflammation and ferroptosis. • We broadened the biomedical application of macrophage membrane as an anti-ferroptosis agent in OA treatment. Osteoarthritis (OA) is a chronic degenerative joint disease characterized by the degradation of articular cartilage while sustained inflammation and ferroptosis have been demonstrated to play crucial roles in the progression of OA. It is an effective strategy to fabricate nanomedicines for OA treatment. However, current research primarily concentrates on anti-inflammation, whereas nanomedicine systems for anti-ferroptosis in OA treatment are rarely reported. Additionally, there are few studies integrating inflammation inhibition with anti-ferroptosis within a single system to ameliorate OA progression. In this study, we introduce a curcumin-loaded biomimetic nanosponge (CM@Cur-NPs) to alleviate OA by synergistically suppressing inflammation and ferroptosis. CM@Cur-NPs were obtained by encapsulating curcumin within polymeric nanoparticles and coating them with macrophage cell membranes. The in vitro and in vivo synergistic anti-inflammatory and anti-ferroptotic effects of CM@Cur-NPs were investigated. It was discovered that the CM@Cur-NPs significantly reduced pro-inflammatory cytokines (TNF-α, IL-6), iNOS, ROS, and apoptosis levels of chondrocytes while concurrently increasing the anti-inflammatory cytokine (IL-4) and extracellular matrix (ECM) content in vitro. We also found that CM@Cur-NPs decreased the expression of the ferroptosis marker Fe2+, ACSL4, and MDA, coupled with an increase in the levels of SLC7A11 and GPX4 of chondrocytes. Lipid peroxidation of chondrocytes was attenuated by CM@Cur-NPs as well. In vivo results indicated that CM@Cur-NPs effectively alleviated OA progression and achieved cartilage protection by upregulating Aggrecan and collagen II expression, along with downregulating ADAMTS5 and MMP13 expression. This study demonstrated that CM@Cur-NPs exhibited enhanced chondroprotective effects through synergistic anti-inflammatory and anti-ferroptotic actions. It is a promising approach to integrate inflammation and ferroptosis inhibition by bioactive nanomaterials for OA treatment. [ABSTRACT FROM AUTHOR]

Abstract: The Lattice Boltzmann Method (LBM) with a forcing scheme is used to simulate homogeneous isotropic turbulence, and the resolutions of 1283 and 2563 are compared. Two models, D3Q15 and D3Q19, are used in the investigation. Results demonstrate that the Lattice Boltzmann Method can capture important features of turbulence such as the vortex-like tubes and the Kolmogorov −5/3 power spectrum. Visualization of the elongated vortices using the high rotational identification method, , is also presented. For 2563, a longer range of the Kolmogorov −5/3 slope can be observed than in the case of 1283 grid points. As the resolution increases, the turbulence characteristics of the flow are found to become similar to those obtained in studies by the spectral method regardless of which model is used. [Copyright &y& Elsevier]

Researches on tunable luminescence and temperature sensitivity of phosphors have become an increasingly popular trend. This paper reports a series of Ca 2 YZr 2 Al 3 O 12 (CYZA):Bi3+, Sm3+ phosphors prepared by solid-state reaction. The phase purity, energy transfer, luminescent properties and temperature sensing performance of the phosphors have been carefully studied. CYZA:Bi3+, Sm3+ phosphors excited by ultraviolet light show tunable color emission, and the color shifts from dark blue to pink due to Bi3+→Sm3+ energy transfer. The related luminescent mechanism of phosphors is also explained. In addition, according to the different thermal sensitivity of Bi3+ and Sm3+, the temperature sensitivity of the phosphors is studied by fluorescence intensity ratio model. The maximum values of absolute sensitivity and relative sensitivity reach up to 0.099% K−1 at 423 K and 0.356% K−1 at 473 K, respectively. These findings indicate that CYZA:Bi3+, Sm3+ phosphors are potential candidates for tunable luminescence and temperature sensing. • The color-tunable property can be obtained in CYZA:Bi3+, Sm3+ phosphors. • Energy transfer from Bi3+ to Sm3+ ions. • Different thermal attenuation behaviors of Bi3+ and Sm3+ ions. • Temperature sensing performance is investigated by FIR model. [ABSTRACT FROM AUTHOR]

Vulnerability detection is important for smart contracts because of their immutable and irreversible features. In this work, a new detection method based on adversarial multi-task learning is proposed to improve the accuracy of existing vulnerability detection methods, which is based on the multi-task learning framework, including a shared part and a task-specific part. We optimize the multi-task learning frameworks and propose the mixed parameter sharing method to make each task not only maintain its uniqueness, but also share features with other tasks, which helps solve the problem that the hard parameter sharing method cannot constrain the underlying shared layer and improve the quality of extracted features. In addition, we introduce adversarial transfer learning to reduce noise pollution caused by the private feature and interference between the general feature and the private feature. We experimented on datasets obtained from our previous work, and the experimental results prove that our proposed model can judge whether there are vulnerabilities in smart contracts and then identify their types. Additionally, the results also show that our model effectively improves detection accuracy and has an advantage in performance over representative methods. [ABSTRACT FROM AUTHOR]

Osteoporosis is a common disease in elderly individuals, and osteoporosis can easily lead to bone and hip fractures that seriously endanger the health of elderly individuals. At present, the treatment of osteoporosis is mainly anti-osteoporosis drugs, but there are side effects associated with anti-osteoporosis drugs. Therefore, it is very important to develop early diagnostic indicators and new therapeutic drugs for the prevention and treatment of osteoporosis. Long noncoding RNAs (lncRNAs), noncoding RNAs longer than 200 nucleotides, can be used as diagnostic markers for osteoporosis, and lncRNAs play an important role in the progression of osteoporosis. Many studies have shown that lncRNAs can be the target of osteoporosis. Therefore, herein, the role of lncRNAs in osteoporosis is summarized, aiming to provide some information for the prevention and treatment of osteoporosis. [ABSTRACT FROM AUTHOR]

Berberine (BBR) has recently been reported to be extensively used for musculoskeletal disorders such as osteoporosis through enhancing osteogenic differentiation, inhibiting osteoclastogenesis and bone resorption and repressing adipogenesis. Although canonical Wnt signaling plays a crucial role in suppressing bone marrow-derived mesenchymal stem cells (MSCs) commitment to the chondrogenic and adipogenic lineage and enhancing osteogenic differentiation, no previous reports have shown an association between BBR-induced osteogenesis and Wnt/β-catenin signaling pathway. In this study, we aimed to investigate the stimulatory effect and the mechanism of BBR on osteogenic differentiation of human bone marrow-derived MSCs. MSCs were isolated from bone marrow specimens and treated with different concentration of BBR. Cell viability was measured by the WST-8 assay. Effects of BBR on osteogenic differentiation of MSCs were assessed by von Kossa staining, ALP staining and ALP activity. Osteogenic specific genes, chondrogenic and adipogenic related marker genes were determined by quantitative real-time polymerase chain reaction analysis. Western blot and Immunofluorescence staining were performed to analyze OCN and OPN, and β-catenin expression in the presence or absence of BBR combined with DKK-1 or β-catenin siRNA transfection. Increasing concentration of BBR (3, 10 and 30 μM) promoted osteogenic differentiation and osteogenic genes expression after incubation for various days compared with DMSO group, whereas expression levels of chondrogenic and adipogenic related marker genes were dramatically suppressed. After treated with 10 μM BBR for 7 days, β-catenin, OPN and OCN expression were significantly induced, which could be effectively suppressed by the addition of DKK-1 or β-catenin siRNA β-catenin. Interestingly, the expression level of Runx2 gene was also decreased by inhibiting the transduction of Wnt/β-catenin signaling. These findings suggest that BBR can stimulate osteogenic differentiation of MSCs not only by enhancing Runx2 expression but also by activating canonical Wnt/β-catenin signaling pathway, and canonical Wnt/β-catenin signaling pathway is in part responsible for BBR-induced osteogenic differentiation of MSCs in vitro. BBR is a potential pharmaceutical medicine by enhancing osteogenic differentiation for bone disorders, such as osteoporosis. [ABSTRACT FROM AUTHOR]

• UV photodetectors based on GaN/PSS/PANI hybrid heterojunction were fabricated. • The photodetector is self-powered, which can work at 0 V bias voltage. • The device can produce a high photocurrent of 2.05 μA in 60 ms under 365 nm light. • The performance of the device can be optimized with the thicknesses of PANI and PSS. A series of highly sensitive and self-powered ultraviolet (UV) photodetectors were prepared. The photodetectors adopt a p-i-n heterojunction structure composed of a layer of molecular beam epitaxy (MBE) grown n-type GaN, a layer of spin coated high resistance poly (styrenesulfonate) (PSS) and a layer of dip-coating applied p-type polyaniline (PANI) synthesized by oxidation reaction. The effects of the thickness of PSS and PANI on device performance were investigated. With the increase of PANI and PSS thickness, the photocurrent increases and reaches the highest value, and then decreases gradually with the further increase of their thickness. The optimized device can rapidly produce a photocurrent of 2.05 μA when illuminated with a 6.7 mW/cm2 UV light at 365 nm without any external power supply. This type of UV photodetector has potential applications in optoelectronics. [ABSTRACT FROM AUTHOR]