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Tissue engineering using adult human mesenchymal stem cells (MSCs) seeded within biomaterial scaffolds has shown the potential to enhance bone healing. Recently, we have developed an injectable, biodegradable methacrylated gelatin‐based hydrogel, which was especially effective in producing scaffolds in situ and allowed the delivery of high viable stem cells and gene vehicles. The well‐demonstrated benefits of recombinant adeno‐associated viral (rAAV) vector, including long‐term gene transfer efficiency and relative safety, combination of gene and cell therapies has been developed in both basic and translational research to support future bone tissue regeneration clinical trials. In this study, we have critically assessed the applicability of single‐step visible light (VL) photocrosslinking fabrication of gelatin scaffold to deliver rAAV encoding human bone morphogenetic protein‐2 (BMP‐2) gene to address the need for sustained BMP‐2 presence localized within scaffolds for the repair of cranial bone defect in mouse model. In this method, rAAV‐BMP‐2 and human bone marrow‐derived MSCs (hBMSCs) were simultaneously included into gelatin scaffolds during scaffold formation by VL illumination. We demonstrated that the subsequent release of rAAV‐BMP‐2 constructs from the scaffold matrix, which resulted in efficient in situ expression of BMP‐2 gene by hBMSCs seeded within the scaffolds, and thus induced their osteogenic differentiation without the supplement of exogenous BMP‐2. The reparative capacity of this novel stem cell‐seeded and gene‐activated scaffolds was further confirmed in the cranial defect in the severe combined immunodeficiency mice, revealed by imaging, histology, and immunohistochemistry at 6 weeks after cranial defect treatment., Schematic diagram of adeno‐associated viral (AAV)‐activated visible light photocrosslinking scaffold for cranial bone defect repair in mice. AAV6‐human bone morphogenetic protein‐2 (BMP‐2) vector and human bone marrow‐derived mesenchymal stem cells (hBMSCs) were simultaneously incorporated into methacrylated gelatin scaffolds during visible light mediated photocrosslinking. We hypothesize that the released AAV6‐BMP‐2 construct from the matrix would result in efficient expression of BMP‐2 gene from hBMSCs co‐seeded within the scaffolds, promoting their osteogenic differentiation, and generating new bone.

With the development of science and technology, the interdisciplinary knowledge penetration has become an important trend in the development of science and technology. Computational thinking is expanding from the field of computer science to other disciplines. The computational thinking is the focus of the information technology in science and engineering. Python teaching is widely used in programming courses in colleges and universities. The combination of theory and practice can stimulate students’ initiative of independent innovation by teaching practice. It can effectively improve the effect and quality of computer thinking training.

It is more practical and efficient to deploy sensors in critical areas rather than common areas to ensure indoor positioning accuracy and reduce deployment cost. This study focused on the sensor placement optimization for critical-grid coverage problem with two objectives: accuracy and cost. After reviewing some related works, this article proposed a multi-objective optimization model for critical-grid coverage problem of indoor positioning considering k-coverage problem as well as the topological rationality of sensor distribution. Then, NSGA-II algorithm was used to solve the optimizing model of sensor placement. At last, the simulation experiment and real environment validation were conducted for proposed method. The results showed that the optimized schemes obtain a lower error (1.13, 1.21 m) and a higher reduction of sensor deployment cost than the uniform deployment scheme (1.44 m). As a conclusion, the proposed method could reduce the cost of sensor deployment while ensuring the accuracy of indoor positioning for critical areas. It also provides a new direction for improving the accuracy of indoor positioning.

In view of the characteristics of IoT engineering talents training, Android program design and teaching objectives, this paper proposes to use the active “project-driven” teaching method in the teaching of Android programming, which helps to improve students' interest in learning, and focus on training and improving IoT students Android program development capabilities. Based on the Active Project-Driven Learning Method, the Android curriculum reform has fully mobilized the enthusiasm and initiative of students in practical teaching. Students can master the overall process of project design and accumulate valuable project experience in learning, which helps to create strong conditions for employment. Project grouping operations can also cultivate students' awareness of teamwork and enhance their ability to communicate and collaboration. Teaching practice has proved that based on job-driven project-driven teaching. Android has achieved good teaching results with feasibility and promotion. A new idea has put forward for the teaching of Android programming course, which is the reference to the teaching of other practical courses of IOT engineering major.

During the epidemic period, we present personalized and hierarchical teaching to expand learning time and space according to the changing teaching methods by information technology. The curriculum reform of data structure as an example, we analyze the question of curriculum teaching in epidemic period. We propose a reform plan for online teaching based on the MOOC platform.

Osteoarthritis (OA), a major cause of pain and disability, is a serious public issue worldwide. Some microRNAs (miRNAs) and SOX9 have been found to be expressed in OA. Therefore, the aim of this study is to investigate effects of microRNA-384-5p (miR-384-5p) on cartilage cell proliferation and apoptosis in mice with OA by targeting SOX9 through the NF-κB signaling pathway. First, bioinformatics was used to predict the SOX9-mediated miRNA (miR-384-5p), and dual luciferase reporter gene assay was conducted to further verify the relationship between miR-384-5p and SOX9. Then, the expression of miR-384-5p, SOX9, and NF-kB in mice modeled with OA was detected. To investigate the specific mechanism of miR-384-5p in OA, mimic and inhibitor of miR-384-5p and siRNA against SOX9 were used to transfect cartilage cells. Finally, proliferation, cell cycle, and cell apoptosis were detected using MTT assay and flow cytometry, respectively. Our results indicated that OA mice exhibited decreased expression of SOX9 and NF-kB but higher miR-384-5p expression. In addition, over-expressed miR-384-5p or silenced SOX9 could inhibit cell proliferation, and block cell cycle entry and induces apoptosis. SOX9 was a target gene of miR-384-5p. The NF-kB signaling pathway was inactivated after overexpression of miR-384-5p. Furthermore, we also observed that the effect of miR-384-5p inhibition was rescued when SOX9 was knocked down. The results support the view that inhibition of miR-384-5p could impede apoptosis and promote proliferation of cartilage cells through activating the NF-κB signaling pathway by promoting SOX9, thereby preventing the development of OA.

Adipose-derived stem cell (ASC)-based therapy is a promising treatment strategy for diseases of the musculoskeletal system, as ASCs have the potential to differentiate into numerous cell lineages. However, this field has only recently been explored; therefore, a considerable amount of work is required to determine the therapeutic potential of ASCs. The mechanisms and factors associated with ASC proliferation and differentiation remain to be elucidated. In order to determine the biological properties and subsequent clinical applications of ASCs, these molecular mechanisms must be investigated. The transcriptional co-activator yes-associated protein (YAP), which is a major target of the Hippo signaling pathway, has been reported to serve a crucial role in stem cell proliferation and differentiation. To the best of our knowledge, the role of YAP in the proliferation and differentiation of rat ASCs (rASCs) has not yet been reported. The results of an immunofluorescence analysis revealed that subcellular distribution of YAP in rASCs was regulated by cell density and the actin cytoskeleton. Furthermore, western blot analysis demonstrated that YAP protein expression in rASCs was regulated by lysophosphatidic acid and the actin cytoskeleton. In addition, YAP activation promoted the proliferation of rASCs, whereas YAP inactivation promoted osteogenesis and inhibited adipogenesis of rASCs. In conclusion, these findings demonstrated that YAP may regulate the proliferation and differentiation of rASCs. Targeted modulation of YAP in rASCs may therefore increase the therapeutic effect of rASCs in musculoskeletal diseases.

Purpose Osteoarthritis (OA) is a degenerative joint disease that leads to the destruction of joint function. The aim of this study is to investigate the effects of microRNA-340-5p (miR-340-5p) and its target gene, FMOD, on the proliferation and apoptosis of chondrocytes in mice with OA through the extracellular signal-regulated kinase (ERK) signaling pathway. Materials Twenty healthy C57BL/6J mice aged 15 months with a weight of 50 ± 2 g were selected. Ten mice were treated using a unilateral knee anterior cruciate ligament transection as well as a medial meniscectomy to establish the OA model. Besides, another 10 mice were used as the control group. Methods A reverse transcription quantitative polymerase chain reaction and Western blot analysis methods were used to examine the expressions of related genes in cells of each group. A 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyl tetrazolium bromide assay and flow cytometry were also conducted to evaluate the cell function after transfection had been completed. Results The expressions of fibromodulin (FMOD), type II collagen (Col II), B-cell lymphoma-2 (Bcl-2), sex-determining region of Y chromosome (SRY)-related high-mobility group-box gene 9 (Sox9), and proliferating cell nuclear antigen (PCNA) were decreased, whereas the expressions of miR-340-5p, runt-related transcription factor-2 (Runx2), Bcl-2-associated X protein (Bax), and ERK1/2 were elevated in the OA mice. Downregulation of miR-340-5p and upregulation of FMOD decreased the expressions of Runx2, Bax, and ERK1/2, and cell apoptosis of chondrocytes, and increased the expressions of FMOD, Col II, Bcl-2, Sox9, and PCNA, and cell proliferation. Conclusion This study suggests that downregulation of miR-340-5p plays a role in promoting cell proliferation and suppressing cell apoptosis of chondrocytes in OA mice through inhibition of the ERK signaling pathway via the FMOD gene.

Aims Cell communication between mesenchymal stem cells and blood vessel cells are crucial for bone repair. We have previously shown that the phyto-molecule icariin significantly promoted osteogenic differentiation of rat adipose-derived stem cells (ASCs). In the present study, we aimed to investigate the relationship between icariin induced osteogenic differentiation of ASCs and angiogenesis of rat endothelial progenitor cells (EPCs). Besides, we used icariin doped 45S5 Bioglass seeded with ASCs to promote bone healing in rat calvarial bone defect models. Main methods The conditioned medium from undifferentiated ASCs (ASCs-CM) and icariin induced ASCs (Icariin-ASCs-CM) was obtained and the vascular endothelial growth factor (VEGF) protein secretion level was measured. The angiogenic capacity and molecular mechanism of ASC-CM and Icariin-ASCs-CM on rat EPCs was analyzed. Rat calvarial bone defect models were established and treated with scaffolds implantation. Micro-CT imaging, histological and immunohistological staining were performed on the isolated specimens at 12 weeks post-surgery. Key findings VEGF protein expression was significantly increased after icariin treatment with the highest expression in the 10−7 M icariin group. Icariin-ASCs-CM obviously increased the angiogenesis of rat EPCs and this capacity was inhibited by a VEGF/VEGF receptor-specific binding inhibitor bevacizumab. Results of the in vivo investigations showed that all scaffolds promoted bone healing compared to the Control group. Icariin significantly improved the healing capacity of 45S5 Bioglass seeded with ASCs. Significance Implantation of Icariin/45S5 Bioglass seeded with rat ASCs could obviously promote both osteogenesis and angiogenesis and therefore represents an ideal candidate bone substitutes for bone repair and regeneration.

Interaction of hypocrellin A (HA), a naturally perylenequinonoid, with fullerene C70 has been studied by UV–vis and fluorescence spectra, and the results show that HA and C70 can form a supramolecular assembly HA/C70 with a 2:1 stoichiometry in organic solvents and buffer solution containing poly(vinylpyrrolidone) (PVP). The triplet lifetime of HA and C70 are reduced due to the formation of supramolecular complex. Electron paramagnetic resonance (EPR) studies suggest that photoinduced electron transfer from N,N,N′N′-tetramethyldiethyleneamine (TMEDA) to the excited HA induces the generation of anion radical of HA (HA −), followed by further electron transfer from HA − to C70. HA can mediate the electron transfer from TMEDA to C70 and significantly enhance the intensity of characteristic Near-IR absorption transition of C70 −, through efficient electron-transfer processes. Upon visible light irradiation, HA/C70 exhibits stronger photodamage ability on calf thymus DNA under anaerobic condition than HA and C70.

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Based on the transient analysis of the compensation capacitor switching, studying the effect of the time of capacitor’s input and removal for grid stability. And based on the stationary solution unchanged, focusing on the general solution of the circuit-order homogeneous linear differential equations and analysis of the effect for the switching current shocks. The results show that the phenomenon of over-current can be avoided. The results of ATP simulation show that, the proposed method can effectively reduce the effect of capacitor switching for grid, improve power quality, and extend the life of the capacitor.

The effects of high-intensity pulsed electromagnetic stimulation (HIPEMS) on proliferation and differentiation of neonatal rat neural stem cells in vitro were investigated. Neural stem cells derived from neonatal rats were exposed to 0.1 Hz, 0.5-10 Tesla (T) [8 groups of B-I, respectively], 5 stimuli of HIPEMF. The sham exposure controls were correspondingly established. Inverted phase contrast microscope was used to observe the cultured cells, MTT assay to detect the viability of the cells as expressed by absorbance (A) value, and flow cytometry to measure differentiation of neural stem cells. The results showed that A values of neural stem cells in both 3.0 T and 4.0 T groups were significantly higher than the other groups 24 to 168 h post HPEMS, indicating a strong promotion of the growth of neural stem cells (P0.05). The A values of neural stem cells in the 6.0 T, 8.0 T, and 10.0 T groups were lower than the sham exposure control group, indicating a restraint of the growth of neural stem cells. The rate of neuron-specific enolase-positive neurons revealed by flow cytometry in HPEMS groups was the same as that in control group (P0.05). It was suggested that 0.1 Hz, 5 pulses stimulation of HPEMS within certain scale of intensity (0.5-10.0 T), significantly promoted the growth of neural stem cells with the rational intensity being 4.0 T.