Special Issue “Bacillus subtilis as a Model Organism to Study Basic Cell Processes”

Bacillus subtilis has served as a model microorganism for many decades [...]

Structural Design Method for Constructions: Simulation, Manufacturing and Experiment

The development of additive manufacturing technology leads to new concepts for design implants and prostheses. The necessity of such approaches is fueled by patient-oriented medicine. Such a concept involves a new way of understanding material and includes complex structural geometry, lattice constructions, and metamaterials. This leads to new design concepts. In the article, the structural design method is presented. The general approach is based on the separation of the micro- and macro-mechanical parameters. For this purpose, the investigated region as a complex of the basic cells was considered. Each basic cell can be described by a parameters vector. An initializing vector was introduced to control the changes in the parameters vector. Changing the parameters vector according to the stress-strain state and the initializing vector leads to changes in the basic cells and consequently to changes in the microarchitecture. A medium with a spheroidal pore was considered as a basic cell. Porosity and ellipticity were used for the parameters vector. The initializing vector was initialized and depended on maximum von Mises stress. A sample was designed according to the proposed method. Then, solid and structurally designed samples were produced by additive manufacturing technology. The samples were scanned by computer tomography and then tested by structural loads. The results and analyses were presented.

Serial RRAM Cell for Secure Bit Concealing

Non-volatile memory cells are exposed to adversary attacks since any active countermeasure is useless when the device is powered off. In this context, this work proposes the association of two serial RRAM devices as a basic cell to store sensitive data, which could solve this bothersome problem. This cell has three states: ‘1’, ‘0’, and masked. When the system is powered off or the data is not used, the cell is set to the masked state, where the cell still stores a ‘1’ or a ‘0’ but a malicious adversary is not capable of extracting the stored value using reverse engineering techniques. Before reading, the cell needs to be unmasked and it is masked afterwards until the next reading request. The operation of the cell also provides robustness against side-channel attacks. The presented experimental results confirm the validity of the proposal.

Models and Paradigms of Cellular Automata With One Active Cell

The chapter describes the basic models and paradigms for constructing asynchronous cellular automata with one active cell. The rules for performing local state functions and local transition functions are considered. The basic cell structures during the transmission of active signals for various local transmission functions are presented. The option is considered when the cell itself selects among the cells in the neighborhood of the cell, a cell that will become active in the next time step, and also the structure with active cells under control is considered. The analysis of cycles that occur in cellular automata with one active cell is carried out, and approaches to eliminating cycles are formulated. Cell structures are constructed and recommendations for their modeling in modern CAD are formulated.

Cell-to-cell Mathematical Modeling of Arrhythmia Phenomena in the Heart

With an aperiodic, self-similar distribution of two-dimensional arrangement of atrial cells, it is possible to simulate such phenomena as Fibrillation, Fluttering, and a sequence of Fibrillation-Fluttering. The topology of a network of cells may facilitate the initiation and development of arrhythmias such as Fluttering and Fibrillation. Using a GPU parallel architecture, two basic cell topologies were considered in this simulation, an aperiodic, fractal distribution of connections among 462 cells, and a chessboard-like geometry of 60×60 and 600×600 cells. With a complex set of initial conditions, it is possible to produce tissue behavior that may be identified with arrhythmias. Finally, we found several sets of initial conditions that show how a mesh of cells may exhibit Fibrillation that evolves into Fluttering.