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Spinal cord injury (SCI) has a high disability rate and poor treatment efficacy and severely affects the health and daily life of patients. Improving the local microenvironment after SCI is crucial for restoring the normal physiological function of the spinal cord. In this study, the injectable near-infrared (NIR) photothermal responsive drug-loaded multiwalled carbon nanotubes (DMWCNTs) containing hydrogel microspheres were prepared by microfluidic technology for SCI treatment. Specifically, paclitaxel (PTX) and vascular endothelial growth factor (VEGF) were loaded into dopamine-modified DMWCNTs, which were then further compounded into gellan gum (GG) by using microfluidic technology to obtain [PTX/VEGF]@DMWCNTs/GG microspheres. The physicochemical properties of the microspheres were characterized using various methods, including transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, optical microscopy, and scanning electron microscopy (SEM). Results showed that microspheres with good injectability and controllable drug release were successfully prepared by using microfluidic technology. The presence of MWCNTs endowed the microspheres with photothermal responsiveness, which led to more drug release under NIR irradiation. The cytotoxicity test results showed that the microspheres had no obvious cytotoxicity and the drug-loaded MWCNTs containing hydrogel microspheres could promote the differentiation of neural stem cells (NSCs). Immunofluorescence results in rats with hemisectioned SCI showed that the microspheres promoted the differentiation of NSCs and the growth of neurons and inhibited the formation of astrocytes and glial scars at the lesion site. In conclusion, the injectable near-infrared photothermal responsive drug-loaded multiwalled carbon nanotube hydrogel microspheres prepared in this study exhibit a promoting effect on SCI repair and provide a strategy for developing transplantation materials for SCI treatment. [ABSTRACT FROM AUTHOR]

In order to solve the problems of performance degradation in energy tower heat pump (ETHP) systems under low temperature conditions and soil heat imbalances in ground source heat pump (GSHP) systems in cold regions, a new coupled system of ETHP and GSHP systems (the ET–GSHP system) and its operating mode were proposed. The mathematical model of the system was constructed along with the system's form and operation scheme. The COP (coefficient of performance) and total energy consumption of the coupled system were then simulated and studied under a number of common operating situations. The heating season is divided into four periods based on varying outdoor ambient temperatures: the first period operates in series mode and has an average outdoor temperature of 2.38 °C; the second period operates in parallel mode and has an average outdoor temperature of −8.56 °C; the third period uses soil source heat pumps to operate separately; and the fourth period operates in series mode and has an average outdoor temperature of −11.32 °C. Operation of the coupled system in four periods was simulated and analyzed, and the operational efficiency and energy saving of the system were analyzed using an actual commercial building in a cold region as an example. The results demonstrate that the ET–GSHP system's overall energy consumption during the heating period is reduced by 4.34% when compared to the traditional GSHP systems; the system's COP can maintain a high level throughout the heating period, with an average COP of 3.315; and the soil temperature at the conclusion of the heating period is 25 °C, which is 8.89 °C higher than that of the traditional GSHP system, providing a guarantee of summer heat return. The new ET–GSHP system significantly boosts the efficiency of the system's operation, achieves effective coupling between various heat sources through multi-stage control, and offers improved energy-saving advantages. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to evaluate the effects of the depletion of SAM and SH3 domain‐containing protein 1 (SASH1) on functional recovery after spinal cord injury (SCI) and to investigate the possible mechanism of SASH1 knockdown in astrocytes facilitating axonal growth. Methods: SCI model was established in adult rats. SASH1 small interfering RNA (siSASH1) was used to investigate its function. Hindlimb motor function was evaluated by the Basso‐Bresnahan‐Beattie (BBB) assay. The gene expressions were evaluated by the methods of qRT‐PCR, Western‐blotting, ELISA, and immunohistochemistry. Results: SASH1 knockdown improved the BBB scores after SCI and significantly reduced GFAP expression. In cultured spinal astrocytes, siSASH1 treatment decreased interferon‐γ release and increased brain‐derived neurotrophic factor (BDNF) release. When cocultured with SASH1‐knockdown astrocytes, axonal growth increased. The neuronal tropomyosin receptor kinase B (BDNF receptor) expression increased, especially in the axonal tips. SASH1 expression increased while NSCs differentiated into glial cells, instead of neurons. After SASH1 depletion, differentiated NSCs maintained a higher level of Nestin protein and an increase in BDNF release. Conclusions: These results indicate that SASH1 acts as an astrocytic differentiation‐maintaining protein, and SASH1 downregulation limits glial activation and contributes toward functional recovery after SCI. [ABSTRACT FROM AUTHOR]

The solar-assisted cold water phase-change energy heat pump system is a clean energy heating system which can effectively reduce the ice melting energy consumption of the cold-water phase-change energy heat pump system. In this paper, the operation mode of the solar-assisted cold-water phase-change energy heat pump system is given, three new ice melting methods are proposed, the performance of three ice melting modes using solar energy for thermal ice melting are simulated, and the influence of ice thickness on system operation is analyzed. The results show that among the three ice melting modes, the affected serial dual-source heat pump mode has the largest system COP, and the pure serial dual-source heat pump mode has the smallest annual total cost. Among the solar collector price, glycol price and electricity price, the change in solar collector price has the greatest impact on the total annual cost, and the change in glycol price has the least impact on the total annual cost. When the ice thickness exceeds 8 mm, the increase in the space heating of the solar-assisted cold water phase-change energy heat pump system becomes smaller, and the increase in heat consumption of ice melting becomes larger. The solar-assisted cold-water phase-change energy heat pump system can simultaneously melt ice and heat, and its economic benefits are significant, with good application and promotion value. [ABSTRACT FROM AUTHOR]