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961.
Qingchao Kong Manlin Qi Wen Li Yujia Shi Jing Su Shimeng Xiao Jiao Sun Xue Bai Biao Dong Lin Wang 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(43):2302547
Porphyrin-based antibacterial photodynamic therapy (aPDT) has found widespread applications in treating periodontitis. However, its clinical use is limited by poor energy absorption, resulting in limited reactive oxygen species (ROS) generation. To overcome this challenge, a novel Z-scheme heterostructured nanocomposite of Bi2S3/Cu-TCPP is developed. This nanocomposite exhibits highly efficient light absorption and effective electron–hole separation, thanks to the presence of heterostructures. The enhanced photocatalytic properties of the nanocomposite facilitate effective biofilm removal. Theoretical calculations confirm that the interface of the Bi2S3/Cu-TCPP nanocomposite readily adsorbs oxygen molecules and hydroxyl radicals, thereby improving ROS production rates. Additionally, the photothermal treatment (PTT) using Bi2S3 nanoparticles promotes the release of Cu2+ ions, enhancing the chemodynamic therapy (CDT) effect and facilitating the eradication of dense biofilms. Furthermore, the released Cu2+ ions deplete glutathione in bacterial cells, weakening their antioxidant defense mechanisms. The synergistic effect of aPDT/PTT/CDT demonstrates potent antibacterial activity against periodontal pathogens, particularly in animal models of periodontitis, resulting in significant therapeutic effects, including inflammation alleviation and bone preservation. Therefore, this design of semiconductor-sensitized energy transfer represents an important advancement in improving aPDT efficacy and the treatment of periodontal inflammation. 相似文献
962.
Zhiwen Zheng Xiaotong Zheng Degang Kong Kai Ding Zhao Zhang Run Zhong Jing He Shaobing Zhou 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(24):2207252
The abnormal pressure in tumor tissue is a significant limitation on the drug delivery efficiency of tumor therapy. This work reports a gradient-driven nanomotor as drug nanocarrier with the pressure-counterworking function. The dual-fuel nanomotors are formed by co-electrospinning of the photosensitive polymers with calcium peroxide (CaO2) and catalase (CAT), followed by ultraviolet (UV) irradiation and bovine serum albumin (BSA) incubation. The UV-responsive cleavage nanomotors can effectively release O2 molecules at the fractures as a driving force to increase the delivery speed and escape the phagocytosis of macrophage system in normal tissues. Furthermore, CAT catalyzes H2O2 produced by CaO2 and the tumor interstitial fluids to provide stronger power for the nanomotors. Additionally, according to the analysis of directional motions of the nanomotors, the functional relationship between the rotational diffusion coefficient (DR) and the physiological viscosity is constructed. The dual-fuel nanocarriers enable up to 13.25% of the injected dose (ID)/per gram tissue and significantly improve the penetration in deep tumor. It is of vital importance to design and obtain the adaptive pressure-gradient counterworking nanomotors, which can effectively improve the drug delivery efficiency in vitro and in vivo. 相似文献
963.
Linchangqing Yang Junfang Li Meng Yin Qingkong Kong Guangcheng Xi 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(28):2300996
Due to the intrinsic layered structure, graphdiyne (GDY) strongly tends to form 2D materials, therefore, most of the current research are based on GDY 2D structures. Up to now, the synthesis of its ultrathin nanowires with a high aspect ratio has not been reported. Here, the ultrathin GDY nanowires with diameters below 3 nm are reported for the first time by a two-phase interface synthesis method, which has excellent crystallinity and an aspect ratio of more than 2500. Evidence shows that the GDY ultrathin nanowires are formed by the oriented-attachment mechanism of nanoparticles. The GDY ultrathin nanowires exhibit a significant quantum confinement effect, enhanced photoelectric effect, and promising applications in surface-enhanced Raman sensing. 相似文献
964.
Lanxing Wang Chunxiao Qi Hongmei Cao Yanwen Zhang Xing Liu Lina Qiu Hang Wang Lijuan Xu Zhenzhou Wu Jianfeng Liu Shusen Wang Deling Kong Yuebing Wang 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(38):2301019
Type 1 diabetes (T1D), which is a chronic autoimmune disease, results from the destruction of insulin-producing β cells targeted by autoreactive T cells. The recent discovery that mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) function as therapeutic tools for autoimmune conditions has attracted substantial attention. However, the in vivo distribution and therapeutic effects of MSC-EVs potentiated by pro-inflammatory cytokines in the context of T1D have yet to be established. Here, it is reported that hexyl 5-aminolevulinate hydrochloride (HAL)-loaded engineered cytokine-primed MSC-EVs (H@TI-EVs) with high expression of immune checkpoint molecule programmed death-legend 1 (PD-L1) exert excellent inflammatory targeting and immunosuppressive effects for T1D imaging and therapy. The accumulated H@TI-EVs in injured pancreas not only enabled the fluorescence imaging and tracking of TI-EVs through the intermediate product protoporphyrin (PpIX) generated by HAL, but also promoted the proliferative and anti-apoptotic effects of islet β cells. Further analysis revealed that H@TI-EVs exhibited an impressive ability to reduce CD4+ T cell density and activation through the PD-L1/PD-1 axis, and induced M1-to-M2 macrophage transition to reshape the immune microenvironment, exhibiting high therapeutic efficiency in mice with T1D. This work identifies a novel strategy for the imaging and treatment of T1D with great potential for clinical application. 相似文献
965.
Mohammed Muhammad Zafran Raja Ng Zi Wei Putranto Aditya Kong Zong Yang Sunarso Jaka Aziz Muhammad Zein Sharif H. Giwangkara Jannata Butar Ivan 《Clean Technologies and Environmental Policy》2023,25(5):1551-1567
Clean Technologies and Environmental Policy - This study aims to propose a new process design, simulation, and techno-economic analysis of an integrated process plant that produces glucose and... 相似文献
966.
A novel linear switched termination active cross‐coupled low‐voltage differential signaling (LVDS) transceiver operating at 1.5 GHz clock frequency is presented. On the transmitter side, an active cross‐coupled linear output driver and a switched termination scheme are applied to achieve high speed with low current. On the receiver side, a shared preamplifier scheme is employed to reduce power consumption. The proposed LVDS transceiver implemented in an 80 nm CMOS process is successfully demonstrated to provide a data rate of 6 Gbps/pin, an output data window of 147 ps peak‐to‐peak, and a data swing of 196 mV. The power consumption is measured to be 4.2 mW/pin at 1.2 V. 相似文献
967.
Chen LL Wu XL Guo YG Kong QS Xia YZ 《Journal of nanoscience and nanotechnology》2010,10(12):8158-8163
Nanostructured composite fibers consisting of carbon coated Mn3O4 nanoparticles (Mn3O4@C) were prepared from thermal decomposition of manganese alginate fibers produced by wet-spinning technique, and investigated with SEM, TEM, XRD, nitrogen adsorption-desorption isotherms, and electrochemical tests toward energy storage. It is found that the as-obtained Mn304@C fibers consist of plenty of nano-sized Mn3O4 crystals with even diameter of 10-15 nm and carbon coating layer with a thickness of 1-2 nm. The composite fibers exhibit also a porous structure consisting of both micropores and mesopores. The electrochemical performances of Mn3O4@C fibers were examined by cyclic voltammetry and galvanostatic charge-discharge techniques. The results indicate that Mn3O4@C fibers possess a higher specific capacitance and superior rate capability when used as electrode materials for supercapacitor compared with commercial Mn3O@4. The improved performances of Mn3O4C fibers can be attributed to the nano-dimension of Mn3O4 particles, the thin carbon coating layer and the nanopores existing among Mn304@C nanoparticles. 相似文献
968.
969.
目前,光折变非线性元件在光学并行图像处理中有着非常广泛的应用。光折变晶体用于图像边缘增强,图像加、减运算,非相干—相干转换(PICOC),图像相关和卷积运算等研究已取得显著成果。本文研究了Cu;KNSBN晶体中多重图像的存贮问题,指出可以利用这种技术实现光学目标识别并给出了一些初步实验结果。此外,还从理论上分析了具有相同衍射效率的多重全息信息记录技术。 相似文献
970.
基于变传动比的线控转向前轮转角控制 总被引:1,自引:0,他引:1
提出一种基于混合智能变传动比技术的前轮转角控制算法;分析了车辆转向性能和转向稳定性的影响因素,利用模糊神经网络设计以控制车辆转向性能为重点的传动比控制器,利用直线拟合方法设计以转向稳定性为重点的传动比控制器,然后应用模糊软切换技术对两传动比进行切换融合,最终得出兼顾转向性能和转向稳定性的恰当总传动比;利用该传动比直接控制前轮转角,并将控制策略进行仿真实验;实验结果表明总传动比不仅在数值范围和曲线形状上更接近理想传动比,而且将对应的峰值速度控制在110km/h左右,优于其他两个分传动比的控制效果;用该传动比控制的整车稳定性和前轮路径跟踪能力较好,可见整个控制策略的有效性。 相似文献