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This paper investigates the neural network (NN) synchronization controller design problem of fractional-order chaotic systems (FOCSs) subject to disturbances and backlash-like hysteresis input. First, we divide the backlash-like hysteresis input into two parts, one of which is the actual controller and the other that can be approximated by NNs. Then, an adaptive NN synchronization control input is implemented to drive the synchronization error between two identical FOCSs into a small domain. Finally, the effect of our approach is indicated by simulation results. [ABSTRACT FROM AUTHOR]

Synchronization problem for a class of uncertain fractional order chaotic systems is studied. Some fundamental lemmas are given to show the boundedness of a complicated infinite series which is produced by differentiating a quadratic Lyapunov function with fractional order. By using the fractional order extension of the Lyapunov stability criterion and the proposed lemma, stability of the closed-loop system is analyzed, and two sufficient conditions, which can enable the synchronization error to converge to zero asymptotically, are driven. Finally, an illustrative example is presented to confirm the proposed theoretical results. [ABSTRACT FROM AUTHOR]

In this paper, we propose the command filtered adaptive fuzzy backstepping control (AFBC) approach for Chua’s chaotic system with external disturbance. Based on two proposed first-order command filters, the convergence of tracking errors as well as the problem of “explosion of complexity” in traditional backstepping design procedure is solved. In the command filtered AFBC design, we do not need to calculate the complicated partial derivatives of the virtual control inputs. Fuzzy logic systems (FLSs) are used to identify the system uncertainties in real time. Based on Lyapunov stability criterion, the proposed controller can guarantee that all signals in the closed-loop system keep bounded, and the tracking errors converge to a small region eventually. Finally, simulation studies have been provided to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper presents an adaptive fuzzy synchronization control strategy for a class of different uncertain fractional-order chaotic/hyperchaotic systems with unknown external disturbances via T-S fuzzy systems, where the parallel distributed compensation technology is provided to design adaptive controller with fractional adaptation laws. T-S fuzzy models are employed to approximate the unknown nonlinear systems and tracking error signals are used to update the parametric estimates. The asymptotic stability of the closed-loop system and the boundedness of the states and parameters are guaranteed by fractional Lyapunov theory. This approach is also valid for synchronization of fractional-order chaotic systems with the same system structure. One constructive example is given to verify the feasibility and superiority of the proposed method. [ABSTRACT FROM AUTHOR]

This paper proposes a fuzzy adaptive control method for uncertain horizontal platform system with unknown control gain, which is capable of guaranteeing the prescribed performance bounds. An error transformation is introduced to transform the original constrained system into an equivalent unconstrained one. Then, based on the error transformation technique and the predefined performance technique, a fuzzy adaptive controller is designed for the unconstrained system. It is shown that all the variables of the resulting closed-loop system are bounded. Finally, an illustrative example is given to demonstrate the effectiveness and usefulness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper proposes a novel image encryption algorithm based on an integer form of chaotic mapping and 2-order bit compass diffusion technique. Chaotic mapping has been widely used in image encryption. If the floating-point number generated by chaotic mapping is applied to image encryption algorithm, it will slow encryption and increase the difficulty of hardware implementation. An innovative pseudo-random integer sequence generator is proposed. In chaotic system, the result of one-iteration is used as the shift value of two binary sequences, the original symmetry relationship is changed, and then XOR operation is performed to generate a new binary sequence. Multiple iterations can generate pseudo-random integer sequences. Here integer sequences have been used in scrambling of pixel positions. Meanwhile, this paper demonstrates that there is an inverse operation in the XOR operation of two binary sequences. A new pixel diffusion technique based on bit compass coding is proposed. The key vector of the algorithm comes from the original image and is hidden by image encryption. The efficiency of our proposed method in encrypting a large number of images is evaluated using security analysis and time complexity. The performance evaluation of algorithm includes key space, histogram differential attacks, gray value distribution(GDV),correlation coefficient, PSNR, entropy, and sensitivity. The comparison between the results of coefficient, entropy, PSNR, GDV, and time complexity further proves the effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]

Ferroptosis is an iron-dependent form of regulated cell death, driven by excessive lipid peroxidation and/or inactivation/depletion of protective molecules against lipid peroxidation. Ionizing radiation can induce ferroptosis in both normal tissues and tumor cells. Here, we reviewed the findings of ionizing radiation-induced ferroptosis. Ionizing radiation induces an increase in hydroxyl radicals, free iron, and lipid metabolic enzymes, which subsequently synergistically initiate a high level of lipid peroxidation, making ionizing radiation an exogenous inducer of ferroptosis. In addition, ferroptosis may be the primary form of cell death in the bone marrow under hematopoietic acute radiation syndrome. Ionizing radiation can also induce changes in iron metabolism, which may be a target for regulating ferroptosis. Finally, ionizing radiation-induced ferroptosis initiates from the cytoplasm and ends on the membrane, and is independent of DNA damage. [ABSTRACT FROM AUTHOR]

Presents an ultrastructural investigation on the ADP-ribosylation factor (ARF)-6 GTPase localization which targets recycling vesicles to the plasma membrane and intercellular endosomal compartments. Methodology used in the investigation; Result sof the investigation; Discussion on the results from the investigation.