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This paper presents a fixed‐time state observer‐based robust adaptive neural fault‐tolerant control (RANFTC) for attitude and altitude tracking and control of quadrotor unmanned aerial vehicles (UAVs), considering multiple actuator faults, parametric uncertainty, and unknown external disturbances simultaneously. A novel fixed‐time state error estimation based on sliding mode observer is designed, which is independent of initial conditions. A proportional–integral–derivative (PID) based sliding mode control (SMC) is proposed to handle actuator faults and unknown disturbances in combination with the fixed‐time observer within the fault‐tolerant control (FTC) design scheme. The radial basis function neural network (RBFNN) is employed with the controller to approximate the uncertain parameters of the system. Furthermore, two new adaptive laws are designed to estimate the sudden actuator fault and the unknown upper bound of disturbances independently. Implementing these estimation schemes avoids overestimation, enhances the robustness of the presented controller, and substantially eliminates the control chattering problem. By applying the Lyapunov stability concept, the suggested control strategy guarantees that the states of the quadrotor UAV converge to the origin in a finite time. Finally, simulation studies are conducted to demonstrate the tracking performance and highlight the effectiveness of the proposed FTC design compared to the existing FTC methods. [ABSTRACT FROM AUTHOR]

Radiochemistry faces a well-documented training and recruitment crisis. Older radiochemists are retiring, and fewer young people are studying radiochemistry. In turn, this is leading to a shortage in newly qualified radiochemists, as well as a loss of historical knowledge (as know-how is often not passed-on). Here, we analyzed the relevance of the study of radiochemistry in higher education through future radiochemists' perceptions. Our objective was to provide insights into future radiochemists' thinking and provide some clear examples on how to support relevance. A qualitative study was conducted through a research question: What perceptions of relevance do future radiochemists experience about radiochemistry studies and radiochemistry as a field? We used the relevance model of Stuckey et al. (2013) as the relevance framework. This was selected because it offers a comprehensive definition of relevance including individual, societal, and vocational dimensions. The data were gathered from postgraduate radiochemistry students (masters and Ph.D. level) through use of a qualitative questionnaire that was designed using the selected relevance framework. In total, 15 future radiochemists participated in the study. The data were analyzed through theory-based content analysis using the selected relevance framework. According to our data, future radiochemists experience their university study and the chemistry field as being highly relevant. They experienced that radiochemistry topics are interesting (individual relevance), the field has great societal impact through radiopharmaceuticals, energy solutions, and environmental problem-solving (societal relevance), and that their professional future was clear, for example, a job in the nuclear industry (vocational relevance). These results can be used in student recruitment and in developing radiochemistry teaching toward a more relevance-oriented direction.

The objective of this project is to develop a numerical approach that simulates the behavior of sloshing water with linear free surface waves on a sloping beach inside a 2D rectangular tank. The current computational approach represents the first stage in the development of a precise modeling framework for wave energy converters (WEC). The 2D tank model was generated using the ANSYS FLUENT program, with the Navier–Stokes equations being discretized on a regular structured grid employing the finite volume method (FVM). The validity of the model has been shown for linear sloshing conditions. Moreover, an examination is conducted to analyze the impact of tank flexibility on the phenomenon of liquid sloshing. The simulation was conducted under seven different wave steepness conditions. The primary objective of this study was to investigate the phenomenon of fluid–structure interaction in the context of movable plates. The investigation of the flow domain encompasses a crucial study on the output power of the plate WEC, specifically focusing on scenarios where plate heights remain constant and the motion of fluid streamlines around the plate is considered. The primary objective of this study is to investigate the relationship between drag force and wave steepness. This observation illustrates a positive correlation between wave steepness and drag force. The revolutionary structure of the ocean buildings may provide a novel and exact method for estimating the wave strength. The usefulness of WEC lies in its capacity to interact with water waves and harness renewable energy from the ocean. This study introduces a novel computational fluid dynamics (CFD) methodology that effectively captures the dynamic interaction between a solid object and a two-phase flow. The examination of the impact of wave steepness on the dynamics of a movable thin plate in intermediate water is a fresh and noteworthy subject of inquiry. This study has substantial importance as a valuable resource for the development of practical systems and possesses direct relevance in the design of WEC for the purpose of harnessing oceanic energy. [ABSTRACT FROM AUTHOR]

RNA-based therapeutics, including siRNA, have obtained recognition in recent years due to their potential to treat various chronic and rare diseases. However, there are still limitations to lipid-based drug delivery systems in the clinical use of RNA therapeutics due to the need for optimization in the design and the preparation process. In this study, we propose adaptive focused ultrasound (AFU) as a drug loading technique to protect RNA from degradation by encapsulating small RNA in nanoliposomes, which we term nanoplexes. The AFU method is non-invasive and isothermal, as nanoplexes are produced without direct contact with any external materials while maintaining precise temperature control according to the desired settings. The controllability of sample treatments can be effectively modulated, allowing for a wide range of ultrasound intensities to be applied. Importantly, the absence of co-solvents in the process eliminates the need for additional substances, thereby minimizing the potential for cross-contaminations. Since AFU is a non-invasive method, the entire process can be conducted under sterile conditions. A minimal volume (300 μL) is required for this process, and the treatment is speedy (10 min in this study). Our in vitro experiments with silencer CD44 siRNA, which performs as a model therapeutic drug in different mammalian cell lines, showed encouraging results (knockdown > 80%). To quantify gene silencing efficacy, we employed quantitative polymerase chain reaction (qPCR). Additionally, cryo-electron microscopy (cryo-EM) and atomic force microscopy (AFM) techniques were employed to capture images of nanoplexes. These images revealed the presence of individual nanoparticles measuring approximately 100–200 nm in contrast with the random distribution of clustered complexes observed in ultrasound-untreated samples of liposome nanoparticles and siRNA. AFU holds great potential as a standardized liposome processing and loading method because its process is fast, sterile, and does not require additional solvents. [ABSTRACT FROM AUTHOR]

The paper analyzes a second-order Stokes wave theory by CFD code and uses the volume of fluid (VOF) method in a 2D numerical wave tank (NWT) in the intermediate depth of water under different wave steepness conditions. The CFD simulation in an NWT generates a wave, validated with the already published experimental and numerical data to check the accuracy. It shows that current results are in good agreement with the published result and the difference in the results is within 2.1027%. Six tests under different wave heights for the time period T = 3. 2 4 s have been conducted in an NWT to verify the analysis of the wave theory. Horizontal and vertical velocity, surface elevation, and the velocity vector of the particle motion are the important objectives in this analysis. The study shows that the free surface of the water is a high energy density zone. The time discretization has been achieved with the first-order implicit scheme and the second-order upwind scheme. This analysis shows that the ocean characteristic of second-order Stokes wave theory on the free surface is important to the engineering sciences and further investigation. [ABSTRACT FROM AUTHOR]