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The purpose of this paper is to investigate the geometric effects and pulsatile characteristics during the stenotic flows in tapering arteries.

The low Reynolds number k − ω turbulence model is applied to describe the stenotic flows in the tapering arteries in this paper. The results are divided into two sections. The first section characterizes the geometric effects on the turbulent flow under steady condition. The second section illustrates the key physiological parameters including the pressure drop and wall stress during the periodic cycle of the pulsatile flow in the arteries.

The tapering and stenoses severity intensify the turbulent flow and stretch the recirculation zones in the turbulent arterial flow. The wall shear stress, pressure drop and velocity vary most intensively at the peak phase during the periodic cycle of the pulsatile turbulent flow.

This paper provides a comprehensive understanding of the spatial‐temporal fluid dynamics involved in turbulent and transitional arterial flow with stenoses. The low Reynolds number k − ω turbulence model method is applied for the analyses of the geometric effects on the arterial flow and fluid feature during the periodic cycle.

The purpose of this paper is to propose a new conceptual framework for big data analytics (BDA) in the healthcare sector for the European Mediterranean region. The objective of this new conceptual framework is to improve the health conditions in a dynamic region characterized by the appearance of new diseases.

This study presents a new conceptual framework that could be employed in the European Mediterranean healthcare sector. Practically, this study can enhance medical services, taking smart decisions based on accurate data for healthcare and, finally, reducing the medical treatment costs, thanks to data quality control.

This research proposes a new conceptual framework for BDA in the healthcare sector that could be integrated in the European Mediterranean region. This framework introduces the big data quality (BDQ) module to filter and clean data that are provided from different European data sources. The BDQ module acts in a loop mode where bad data are redirected to their data source (e.g. European Centre for Disease Prevention and Control, university hospitals) to be corrected to improve the overall data quality in the proposed framework. Finally, clean data are directed to the BDA to take quick efficient decisions involving all the concerned stakeholders.

This study proposes a new conceptual framework for executives in the healthcare sector to improve the decision-making process, decrease operational costs, enhance management performance and save human lives.

This study focused on big data management and BDQ in the European Mediterranean healthcare sector as a broadly considered fundamental condition for the quality of medical services and conditions.

Coronary artery disease (CAD) is reported as one of the most common sources of death all over the world. The presence of stenosis (plaque) in the coronary arteries results in the restriction of blood supply, leading to myocardial infarction. The current study investigates the influence of multi stenosis on hemodynamic properties in a patient-specific left coronary artery.

A three-dimensional model of the patient-specific left coronary artery was reconstructed based on computed tomography (CT) scan images using MIMICS-20 software. The diseased model of the left coronary artery was investigated, having the narrowing of 90% and 70% of area stenosis (AS) at the left anterior descending (LAD) and left circumflex (LCX), respectively.

The results indicate that the upstream region of stenosis experiences very high pressure for 90% AS during the systolic period of the cardiac cycle. The pressure drops maximum as the flow travels into the stenotic zone, and the high flow velocities were observed across the 90% AS. The higher wall shear stresses occur at the stenosis region, and it increases with the increase in the flow rate. It is found that the maximum wall shear stress across 90% AS is at the highest risk for rupture. A recirculation region immediately after the stenosis results in the further development of stenosis.

The current study provides evidence that there is a strong effect of multi-stenosis on the blood flow in the left coronary artery.

The coupling impact of hybrid uncertain errors on the machine precision is complex, as a result of which the designing method with multiple independent error sources under uncertainties remains a challenge. For the purpose of precision improvement, this paper focuses on the robot design and aims to present an assembly precision design method based on uncertain hybrid tolerance allocation (UHTA), to improve the positioning precision of the mechanized robot, as well as realize high precision positioning within the workspace.

The fundamentals of the parallel mechanism are introduced first to implement concept design of a 3-R(4S) &3-SS parallel robot. The kinematic modeling of the robot is carried out, and the performance indexes of the robot are calculated via Jacobian matrix, on the basis of which, the 3D spatial overall workspace can be quantified and visualized, under the constraints of limited rod, to avoid the singular position. The error of the robot is described, and a probabilistic error model is hereby developed to classify the hybrid error sensitivity of each independent uncertain error source by Monte Carlo stochastic method. Most innovatively, a methodology called UHTA is proposed to optimize the robot precision, and the tolerance allocation approach is conducted to reduce the overall error amplitude and improve the robotized positioning precision, on the premise of not increasing assembly cost.

The proposed approach is validated by digital simulation of medical puncture robot. The experiment highlights the mathematical findings that the horizontal plane positioning error of the parallel robotic mechanism can be effectively reduced after using UHTA, and the average precision can be improved by up to 39.54%.

The originality lies in UHTA-based precision design method for parallel robots. The proposed method has widely expanding application scenarios in industrial robots, biomedical robots and other assembly automation fields.

This paper aims to concentrate on recent innovations in flexible wearable sensor technology tailored for monitoring vital signals within the contexts of wearable sensors and systems developed specifically for monitoring health and fitness metrics.

In recent decades, wearable sensors for monitoring vital signals in sports and health have advanced greatly. Vital signals include electrocardiogram, electroencephalogram, electromyography, inertial data, body motions, cardiac rate and bodily fluids like blood and sweating, making them a good choice for sensing devices.

This report reviewed reputable journal articles on wearable sensors for vital signal monitoring, focusing on multimode and integrated multi-dimensional capabilities like structure, accuracy and nature of the devices, which may offer a more versatile and comprehensive solution.

The paper provides essential information on the present obstacles and challenges in this domain and provide a glimpse into the future directions of wearable sensors for the detection of these crucial signals. Importantly, it is evident that the integration of modern fabricating techniques, stretchable electronic devices, the Internet of Things and the application of artificial intelligence algorithms has significantly improved the capacity to efficiently monitor and leverage these signals for human health monitoring, including disease prediction.

The COVID-19 pandemic is indeed a once-in-a-lifetime emergency. While it seems that the end is nigh, there is also a renewed talk of the looming fourth wave spurred by the mutated Delta, Delta+, and other variants. The pandemic has made several fault lines visible in almost all societies. These include but are not limited to the tentativeness of our knowledge (especially science), the precariousness of our health systems, and failings of the educational systems, particularly citizenship education. While the COVID-19 pandemic will be long remembered as the health crisis of our times; we contend that the pandemic is also an educational crisis. Results of neoliberal neglect of citizenship-related education are now apparent in form of unethical, unjust, racist, and socially irresponsible attitudes and behaviors of individuals, collectives, and states. At the individual level, these are obvious in the irresponsible behaviors that endanger the lives of fellow citizens. At the community level, the failure of citizenship education is evident in vaccination inequality both within and between societies. Finally, at the level of international community, one can see vaccination nationalism, and politically and economically motivated vaccination diplomacy as markers of unethical citizenship.

This paper aims to develop a novel type of bionic underwater robot (BUR) with multi-flexible caudal fins. With the coordinate movement of multi-caudal fins, BUR will combine the undulation propulsion mode of carangiform fish and jet propulsion mode of jellyfish together organically. The use of Computational Fluid Dynamics (CFD) and experimental method helps to reveal the effect of caudal fin stiffness and motion parameters on its hydrodynamic forces.

First, the prototype of BUR was given by mimicking the shape and propulsion mechanism of both carangiform fish and jellyfish. Besides, the kinematics models in both undulation and jet propulsion modes were established. Then, the effects of caudal fin stiffness on its hydrodynamic forces were investigated based on the CFD method. Finally, an experimental set-up was developed to test and verify the effects of the caudal fin stiffness on its hydrodynamic forces under different caudal fin actuation frequency and amplitude.

The results of this paper demonstrate that BUR with multi-flexible caudal fins combines the hydrodynamic characteristics of undulation and jet propulsion modes. In addition, the caudal fin with medium stiffness can generate larger thrust force and reduce the reactive power.

This paper implies that robotic fish can be equipped with both undulation and jet propulsion modes to optimize the swimming performance in the future.

This paper provides a BUR with multi-propulsion modes, which has the merits of high propulsion efficiency, high acceleration performance and overcome the head shaken problem effectively.

The magnetohydrodynamic (MHD) flow problems are important in the field of biomedical applications such as magnetic resonance imaging, inductive heat treatment of tumours, MHD-derived biomedical sensors, micropumps for drug delivery, MHD micromixers, magnetorelaxometry and actuators. Therefore, there is the impact of the magnetic field on the transport of non-Newtonian Carreau fluid in the presence of binary chemical reaction and activation energy over an extendable surface having a variable thickness. The significance of irregular heat source/sink and cross-diffusion effects is also explored.

The leading governing equations are constructed by retaining the effects of binary chemical reaction and activation energy. Suitable similarity transformations are used to transform the governing partial differential equations into ordinary differential equations. Subsequent nonlinear two-point boundary value problem is treated numerically by using the shooting method based on Runge–Kutta–Fehlberg. Graphical results are presented to analyze the behaviour of effective parameters involved in the problem. The numerical values of the mass transfer rate (Sherwood number) and heat transfer rate (Nusselt number) are also calculated. Furthermore, the slope of the linear regression line through the data points is determined in order to quantify the outcome.

It is established that the external magnetic field restricts the flow strongly and serves as a potential control mechanism. It can be concluded that an applied magnetic field will play a major role in applications like micropumps, actuators and biomedical sensors. The heat transfer rate is enhanced due to Arrhenius activation energy mechanism. The boundary layer thickness is suppressed by strengthening the thickness of the sheet, resulting in higher values of Nusselt and Sherwood numbers.

The effects of magnetic field, binary chemical reaction and activation energy on heat and mass transfer of non-Newtonian Carreau liquid over an extendable surface with variable thickness are investigated for the first time.

The purpose of this study is to assess the opportunity for a distributed, networked open biomedical repository (OBR) using a knowledge management system (KMS) conceptual framework. An innovative KMS conceptual framework is proposed to guide the transition from a traditional, siloed approach to a sustainable OBR.

This paper reports on a cycle of action research, involving literature review, interviews and focus group with leaders in biomedical research, open science and librarianship, and an audit of elements needed for an Australasian OBR; these, along with an Australian KM standard, informed the resultant KMS framework.

The proposed KMS framework aligns the requirements for an OBR with the people, process, technology and content elements of the KM standard. It identifies and defines nine processes underpinning biomedical knowledge – discovery, creation, representation, classification, storage, retrieval, dissemination, transfer and translation. The results comprise an explanation of these processes and examples of the people, process, technology and content dimensions of each process. While the repository is an integral cog within the collaborative, distributed open science network, its effectiveness depends on understanding the relationships and linkages between system elements and achieving an appropriate balance between them.

The current research has focused on biomedicine. This research builds on the worldwide effort to reduce barriers, in particular paywalls to health knowledge. The findings present an opportunity to rationalize and improve a KMS integral to biomedical knowledge.

Adoption of the KMS framework for a distributed, networked OBR will facilitate open science through reducing duplication of effort, removing barriers to the flow of knowledge and ensuring effective management of biomedical knowledge.

Achieving quality, permanency and discoverability of a region’s digital assets is possible through ongoing usage of the framework for researchers, industry and consumers.

The framework demonstrates the dependencies and interplay of elements and processes to frame an OBR KMS.