A Review on Recognition of Explosives using Calixarene Framework

In terms of social security and support, quick, ultra-sensitive, and ultra-selective detection of explosives is urgently needed around the world. This review is ardent to calixarene a recent selective and sensitive explosive sensor. The structural binding properties of the Calix system and macromolecules can be modified by various structural mode changes and interactions, and multiple possibilities of functionalization of the calixarene make these versatile molecules in the phenomena of specific recognition. This study reflects on the use of fluorescence-based chemosensors for explosive detection that has been mentioned in the literature. From this review, it is implied that calixarene excellently complexes with high selectivity explosives and attraction associated with other simple ion receptor applications using different ions.

Potent neutralization of SARS-CoV-2 variants of concern by an antibody with a unique genetic signature and structural mode of spike recognition

The emergence of novel SARS-CoV-2 lineages that are more transmissible and resistant to currently approved antibody therapies poses a considerable challenge to the clinical treatment of COVID-19. Therefore, the need for ongoing discovery efforts to identify broadly reactive monoclonal antibodies to SARS-CoV-2 is of utmost importance. Here, we report a panel of SARS-CoV-2 antibodies isolated using the LIBRA-seq technology from an individual who recovered from COVID-19. Of these antibodies, 54042-4 showed potent neutralization against authentic SARS-CoV-2 viruses, including variants of concern (VOCs). A cryo-EM structure of 54042-4 in complex with the SARS-CoV-2 spike revealed an epitope composed of residues that are highly conserved in currently circulating SARS-CoV-2 lineages. Further, 54042-4 possesses unique genetic and structural characteristics that distinguish it from other potently neutralizing SARS-CoV-2 antibodies. Together, these findings motivate 54042-4 as a lead candidate for clinical development to counteract current and future SARS-CoV-2 VOCs.

Shining a Light on Colibactin Biology

Colibactin is a secondary metabolite encoded by the pks gene island identified in several Enterobacteriaceae, including some pathogenic Escherichia coli (E. coli) commonly enriched in mucosal tissue collected from patients with inflammatory bowel disease and colorectal cancer. E. coli harboring this biosynthetic gene cluster cause DNA damage and tumorigenesis in cell lines and pre-clinical models, yet fundamental knowledge regarding colibactin function is lacking. To accurately assess the role of pks+ E. coli in cancer etiology, the biological mechanisms governing production and delivery of colibactin by these bacteria must be elucidated. In this review, we will focus on recent advances in our understanding of colibactin’s structural mode-of-action and mutagenic potential with consideration for how this activity may be regulated by physiologic conditions within the intestine.

Frequency-Spectra-Based High Coding Capacity Chipless RFID Using an UWB-IR Approach

A novel methodology is proposed to reliably predict the resonant characteristics of a multipatch backscatter-based radio frequency identification (RFID) chipless tag. An ultra-wideband impulsion radio (UWB-IR)-based reader interrogates the chipless tag with a UWB pulse, and analyzes the obtained backscatter in the time domain. The RFID system consists of a radar cross-section (RCS)-based chipless tag containing a square microstrip patch antenna array in which the chipless tag is interrogated with a UWB pulse by an UWB-IR-based reader. The main components of the backscattered signal, the structural mode, and the antenna mode were identified and their spectral quality was evaluated. The study revealed that the antenna-mode backscatter includes signal carrying information, while the structural mode backscatter does not include any tag information. The simulation findings were confirmed by experimental measurements obtained in an anechoic chamber environment using a 6-bit multipatch chipless RFID tag. Finally, the novel technique does not use calibration tags and can freely orient tags with respect to the reader.

A Variable Structural Control for a Hybrid Hyperbolic Dynamic System

In this paper, we are concerned with a hybrid hyperbolic dynamic system formulated by partial differential equations with initial and boundary conditions. First, the system is transformed to an abstract evolution system in an appropriate Hilbert space, and spectral analysis and semigroup generation of the system operator is discussed. Subsequently, a variable structural control problem is proposed and investigated, and an equivalent control method is introduced and applied to the system. Finally, a significant result that the state of the system can be approximated by the ideal variable structural mode under control in any accuracy is derived and examined.

THE CONCEPT OF CONSTRUCTING SET-THEORETIC MODELS OF STRUCTURES OF INTELLIGENT MULTI-AXIS MECHATRONIC ROBOT MODULES

The article discusses the features and areas of application of multi-axis electromagnetic mechatronic modules in modules of mechatronic and robotic systems that allow not only to increase productivity and improve the quality of manufactured products, but also by replacing heavy, monotonous and sometimes associated with a risk to human health, manual labor with a machine to release a person for creative constructive work. The generalized structure of a multi-axis mechatronic module is presented; multiple theoretical models of construction principles for the study of electromagnetic mechatronic modules of robots and robotic systems are constructed. In this case, the main attention is paid to the determination of the main and auxiliary sources of the magnetic field in such modules. An algorithm for the formation of equations for electromagnetic mechatronic modules is given on the example of an electromagnetic mechatronic module with linear motion, formed from electrical, magnetic and mechanical components interconnected with each other. The algorithm includes questions of constructing a structural model, the transition from a structural model to a structural-mode model, the choice of variables and connections between the electrical, magnetic and mechanical parts of the module, writing the equations of nodal parallel or contour sequential variables according to the structural-mode model, depending on the appropriateness of one or another method for specific components of the mechatronic module.