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The intrinsic variability of memristor switching behavior can be used as a natural source of randomness, this variability is valuable for safe applications in hardware, such as the true random number generator (TRNG). However, the speed of TRNG is still be further improved. Here, we propose a reliable Ag/SiNx/n-Si volatile memristor, which exhibits a typical threshold switching device with stable repeat ability and fast switching speed. This volatile-memristor-based TRNG is combined with nonlinear feedback shift register (NFSR) to form a new type of high-speed dual output TRNG. Interestingly, the bit generation rate reaches a high speed of 112 kb/s. In addition, this new TRNG passed all 15 National Institute of Standards and Technology (NIST) randomness tests without post-processing steps, proving its performance as a hardware security application. This work shows that the SiNx-based volatile memristor can realize TRNG and has great potential in hardware network security. [ABSTRACT FROM AUTHOR]

Neuromorphic computing aims to achieve artificial intelligence by mimicking the mechanisms of biological neurons and synapses that make up the human brain. However, the possibility of using one reconfigurable memristor as both artificial neuron and synapse still requires intensive research in detail. In this work, Ag/SrTiO3(STO)/Pt memristor with low operating voltage is manufactured and reconfigurable as both neuron and synapse for neuromorphic computing chip. By modulating the compliance current, two types of resistance switching, volatile and nonvolatile, can be obtained in amorphous STO thin film. This is attributed to the manipulation of the Ag conductive filament. Furthermore, through regulating electrical pulses and designing bionic circuits, the neuronal functions of leaky integrate and fire, as well as synaptic biomimicry with spike-timing-dependent plasticity and paired-pulse facilitation neural regulation, are successfully realized. This study shows that the reconfigurable devices based on STO thin film are promising for the application of neuromorphic computing systems. [ABSTRACT FROM AUTHOR]

This paper studies the automatic carrier landing controller design problem with output constraint and fixed-time convergence requirements. The proposed flight controller is separated into guidance, attitude control, and approach power compensation system. In each submodule, universal barrier Lyapunov function and fixed-time control scheme are applied in the controller design. In addition, adaptive estimation method is incorporated to improve the robustness to the external disturbances. The proposed controller ensures the position tracking error, attitude tracking error, and angle of attack tracking error not violate the predesigned boundaries, while the tracking errors will converge to a small set around zero in fixed-time. The output constraint and fixed-time convergence properties of the proposed controller improve the landing security to a narrow flight deck in a limited operation time. The simulation results verify the proposed controller in automatic carrier landing mission. [ABSTRACT FROM AUTHOR]

This study examined the effect of once‐weekly parathyroid hormone (PTH) combined with alendronate upon osteoporotic fracture healing after long‐term alendronate anti‐osteoporosis therapy. Seventy‐six 12‐week‐old female Sprague–Dawley rats were either sham operated or bilaterally ovariectomized (OVX). Following confirmation of osteoporosis 3 months after OVX, the remaining 64 animals received alendronate therapy. After 3 months of alendronate treatment, all rats underwent unilateral transverse tibial osteotomy. Animals were immediately randomly assigned to one of four groups: (1) alendronate followed by vehicle (ALN‐VEH), (2) continuation of alendronate (ALN‐ALN), (3) alendronate followed by once‐weekly PTH alone (ALN‐PTH), (4) continuation of alendronate combined with once‐weekly PTH (ALN‐ALN + PTH) until collection at 4 or 8 weeks after osteotomy. The fractured tibia was assessed using x‐ray, dual‐energy x‐ray absorptiometry, microcomputed tomography, biomechanical testing, histology, and sequential fluorescence labeling. The ALN‐ALN + PTH treatment significantly increased total callus volume, mineralized callus volume, mineralized callus volume/total callus volume, and biomechanical strength of the callus relative to ALN‐VEH and ALN‐PTH treatments at both 4 and 8 weeks and produced more mature trabecular bone compared with ALN‐ALN treatment at 8 weeks. RANKL/osteoprotegerin (OPG) are osteoclastogenesis markers, while cluster of differentiation 31 (CD31) is an important marker of angiogenesis. Qualitative immunohistochemical analysis revealed that CD31 and OPG expression was was strong after ALN‐ALN + PTH compared with ALN‐ALN treatment, whereas RANKL expression was weak after ALN‐ALN + PTH versus ALN‐PTH treatment. Our study showed that once‐weekly PTH combined with alendronate was beneficial in promoting the healing of fractures acquired after long‐term alendronate therapy in OVX‐induced osteoporotic rats. [ABSTRACT FROM AUTHOR]

Immunotherapies provide effective strategies for cancer treatment. Cholesterol induces CD8 + T cell exhaustion, which inhibits antitumor immunity. CD8 + T cells are derived from bone marrow and transport and function in bone marrow, where provides more porous cavities for drugs to access the circulation than other solid organs. We previously found that single-dose intraosseous (i.o.) injection of simvastatin suppresses breast cancer development and prolongs survival, but the exact mechanism remains unclear. In this study, we found the antitumor activity of simvastatin i.o. mainly depended on CD8 + T cells. Simvastatin i.o. increased the percentage and cytotoxicity of CD8 + T cells and downregulated the expression of PD-1, TIM3 and CTLA4 in CD8 + T cells in vivo. Simvastatin promoted the activation, proliferation and cytotoxicity of tumor antigen-specific CD8 + T cells in vitro. Furthermore, Simvastatin i.o. suppressed cancers by activating the T-cell antigen receptor signaling pathway. Taken together, simvastatin i.o. effectively suppresses cancer progression, which would be a potential strategy for cancer treatment., Competing Interests: Conflicts of interest statement The authors declare that there are no conflicts of interest., (Copyright © 2022 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)