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In two previous papers, we calculated the dielectrophoresis (DEP) force and corresponding trajectories of high- and low-conductance 200-µm 2D spheres in a square 1 × 1-mm chamber with plane-versus-pointed, plane-versus-plane and pointed-versus-pointed electrode configurations by applying the law of maximum entropy production (LMEP) to the system. Here, we complete these considerations for configurations with four-pointed electrodes centered on the chamber edges. The four electrodes were operated in either object-shift mode (two adjacent electrodes opposite the other two adjacent electrodes), DEP mode (one electrode versus the other three electrodes), or field-cage mode (two electrodes on opposite edges versus the two electrodes on the other two opposite edges). As in previous work, we have assumed DC properties for the object and the external media for simplicity. Nevertheless, every possible polarization ratio of the two media can be modeled this way. The trajectories of the spherical centers and the corresponding DEP forces were calculated from the gradients of the system's total energy dissipation, described by numerically-derived conductance fields. In each of the three drive modes, very high attractive and repulsive forces were found in front of pointed electrodes for the high and low-conductance spheres, respectively. The conductance fields predict bifurcation points, watersheds, and trajectories with multiple endpoints. The high and low-conductance spheres usually follow similar trajectories, albeit with reversed orientations. In DEP drive mode, the four-point electrode chamber provides a similar area for DEP measurements as the classical plane-versus-pointed electrode chamber. [ABSTRACT FROM AUTHOR]

In two previous papers, we calculated the dielectrophoresis (DEP) force and corresponding trajectories of high- and low-conductance 200-µm 2D spheres in a square 1 × 1-mm chamber with plane-versus-pointed, plane-versus-plane and pointed-versus-pointed electrode configurations by applying the law of maximum entropy production (LMEP) to the system. Here, we complete these considerations for configurations with four-pointed electrodes centered on the chamber edges. The four electrodes were operated in either object-shift mode (two adjacent electrodes opposite the other two adjacent electrodes), DEP mode (one electrode versus the other three electrodes), or field-cage mode (two electrodes on opposite edges versus the two electrodes on the other two opposite edges). As in previous work, we have assumed DC properties for the object and the external media for simplicity. Nevertheless, every possible polarization ratio of the two media can be modeled this way. The trajectories of the spherical centers and the corresponding DEP forces were calculated from the gradients of the system’s total energy dissipation, described by numerically-derived conductance fields. In each of the three drive modes, very high attractive and repulsive forces were found in front of pointed electrodes for the high and low-conductance spheres, respectively. The conductance fields predict bifurcation points, watersheds, and trajectories with multiple endpoints. The high and low-conductance spheres usually follow similar trajectories, albeit with reversed orientations. In DEP drive mode, the four-point electrode chamber provides a similar area for DEP measurements as the classical plane-versus-pointed electrode chamber.

The concept of targeted and controlled drug delivery, which directs treatment to precise anatomical sites, offers benefits such as fewer side effects, reduced toxicity, optimized dosages, and quicker responses. However, challenges remain to engineer dependable systems and materials that can modulate host tissue interactions and overcome biological barriers. To stay aligned with advancements in healthcare and precision medicine, novel approaches and materials are imperative to improve effectiveness, biocompatibility, and tissue compliance. Electronically controlled drug delivery (ECDD) has recently emerged as a promising approach to calibrated drug delivery with spatial and temporal precision. This article covers recent breakthroughs in soft, flexible, and adaptable bioelectronic micro-systems designed for ECDD. It overviews the most widely reported operational modes, materials engineering strategies, electronic interfaces, and characterization techniques associated with ECDD systems. Further, it delves into the pivotal applications of ECDD in wearable, ingestible, and implantable medical devices. Finally, the discourse extends to future prospects and challenges for ECDD., (© 2023 The Authors. Advanced Healthcare Materials published by Wiley‐VCH GmbH.)

The paper deals with the classification, applications, and advantages of microelectromechanical systems (MEMS), materials, and technologies used. This area of production represents one of the most promising technologies of 21st century, with a big impact in manufacturing 4.0. Nowadays, MEMS fabrication methods have a very big influence in the area of medicine, and therefore the review applications of utmost importance like micromechanical stents or antenna stents are related. The study presents information about MEMS based micro‐EDM, regarding working parameters and some examples of techniques used to realize MEMS devices. These have the purpose to minimize the cost together with the increase of the output technological parameters. The process capabilities of micro‐ECM, associated with working parameters are also treated, and the potential applications in industries like automotive, aerospace, biomedical, security, communication, etc. Finally, some future challenges of MEMS application in the specified fields are exposed. [ABSTRACT FROM AUTHOR]

Targeted delivery of pharmaceuticals is promising for efficient disease treatment and reduction in adverse effects. Nano or microstructured magnetic materials with strong magnetic momentum can be noninvasively controlled via magnetic forces within living beings. These magnetic carriers open perspectives in controlling the delivery of different types of bioagents in humans, including small molecules, nucleic acids, and cells. In the present review, we describe different types of magnetic carriers that can serve as drug delivery platforms, and we show different ways to apply them to magnetic targeted delivery of bioagents. We discuss the magnetic guidance of nano/microsystems or labeled cells upon injection into the systemic circulation or in the tissue; we then highlight emergent applications in tissue engineering, and finally, we show how magnetic targeting can integrate with imaging technologies that serve to assist drug delivery. [ABSTRACT FROM AUTHOR]

Targeted delivery of pharmaceuticals is promising for efficient disease treatment and reduction in adverse effects. Nano or microstructured magnetic materials with strong magnetic momentum can be noninvasively controlled via magnetic forces within living beings. These magnetic carriers open perspectives in controlling the delivery of different types of bioagents in humans, including small molecules, nucleic acids, and cells. In the present review, we describe different types of magnetic carriers that can serve as drug delivery platforms, and we show different ways to apply them to magnetic targeted delivery of bioagents. We discuss the magnetic guidance of nano/microsystems or labeled cells upon injection into the systemic circulation or in the tissue; we then highlight emergent applications in tissue engineering, and finally, we show how magnetic targeting can integrate with imaging technologies that serve to assist drug delivery.

This work presents the results of the experimental and theoretical study of the static pull-in of tilting actuation executed by a hybrid levitation micro-actuator (HLMA) based on the combination of inductive levitation and electrostatic actuation. A semi-analytical model to study such a pull-in phenomenon is developed, for the first time, as a result of using the qualitative technique based on the Lagrangian approach to analyze inductive contactless suspensions and a recent progress in the calculation of mutual inductance and force between two circular filaments. The obtained non-linear model, accounting for two degrees of freedom of the actuator, allows us to predict accurately the static pull-in displacement and voltage. The results of modeling were verified experimentally and agree well with measurements.

The technique of solid phase micro-extraction (SPME) is an important method for sample pretreatment in analytical chemistry, especially for the analysis in micro-systems. Surface enhanced Raman scattering (SERS) is an ultra-sensitive and fast detection technique. Both are particularly important in qualitative analysis of trace amount of substance. In this study, combining the magnetic nanoparticles with magnetic SPME device, we develop a high efficient new pretreatment method named as disperse magnetic solid phase micro-extraction (Dis-MSPME). In comparison to the traditional SPME, the proposed Dis-MSPME realizes solid phase micro-extraction from dispersive system, which improved the extraction efficiency largely. Conjunction the advantages both of Dis-MSPME and SERS is proposed as Dis-MSPME-SERS as a new detection method, which realize enrichment, magnetic separation and detection all-in-one. Making it a simpler, more efficient and sensitive approach in identifying the illegal additives. Sildenafil citrate (SC) in 500 μL health wine as an example of illegal additive was successfully detected in a LOD of 1.0 × 10 −8 M. Moreover, comparative study on the extract efficient of Dis-MSPME-SERS with SPME-SERS shows it takes only 10 min to detect sildenafil citrate in the health wine, from enrichment to detection by Dis-MSPME-SERS. [ABSTRACT FROM AUTHOR]

In this article we present a qualitative approach to study the dynamics and stability of micro-machined inductive contactless suspensions (MIS). In the framework of this approach, the induced eddy current into a levitated micro-object is considered as a collection of m -eddy current circuits. Assuming small displacements and the quasi-static behavior of the levitated micro-object, a generalized model of MIS is obtained and represented as a set of six linear differential equations corresponding to six degrees of freedom in a rigid body by using the Lagrange-Maxwell formalism. The linear model allows us to investigate the general stability properties of MIS as a dynamic system, and these properties are synthesized in three major theorems. In particular we prove that the stable levitation in the MIS without damping is impossible. Based on the approach presented herewith, we give general guidelines for designing MIS. Additionally, we demonstrate the successful application of this technique to study the dynamics and stability of symmetric and axially symmetric MIS designs, both based on 3D micro-coil technology. [ABSTRACT FROM AUTHOR]

Through remote forces, levitating micro-actuators completely eliminate mechanical attachment between the stationary and moving parts of a micro-actuator, thus providing a fundamental solution to overcoming the domination of friction over inertial forces at the micro-scale. Eliminating the usual mechanical constraints promises micro-actuators with increased operational capabilities and low dissipation energy. Further reduction of friction and hence dissipation by means of vacuum leads to dramatic increases of performance when compared to mechanically tethered counterparts. In order to efficiently employ the benefits provided by levitation, micro-actuators are classified according to their physical principles as well as by their combinations. Different operating principles, structures, materials and fabrication methods are considered. A detailed analysis of the significant achievements in the technology of micro-optics, micro-magnets and micro-coil fabrication, along with the development of new magnetic materials during recent decades, which has driven the creation of new application domains for levitating micro-actuators is performed.

Background: Leadership development impacts on quality of care and on workplace cultures for staff. Clinical leadership embracing transformational and other collective leadership approaches is a key enabler for developing effective workplace cultures at the micro-systems level. Following the development of a shared purpose and values framework, an internal interprofessional clinical leadership programme was set up to grow a critical community of transformational leaders across one NHS organisation in England. This programme had been unsuccessful in engaging medical doctors for more than two years. Aims and objectives: This paper shares how a dedicated, practice development-based clinical leadership programme set out to support medical doctors across one organisation with their leadership journey, equipping them to become transformational and collective leaders, and facilitators with the skills to develop and sustain person-centred, safe and effective workplace cultures. Methods: Practice development methodology, with its collaborative, inclusive and participative approach to developing person-centred cultures, combined with clinical leadership strategies, formed the basis of the programme. It emphasised the use of active and action learning, drawing on the workplace as the main resource for learning, development and improvement. Self-assessment and collective thinking about clinical leadership, together with collaborative analysis of evaluation data, led to the synthesis of insights through the use of reflection and action planning. Findings: These are presented at two levels: 1. Five individual reflections by authors to illustrate their leadership journeys, which also demonstrate the use of a range of tools and their impact. Insights and learning include recognition of the benefits of peer support and networking, development of a disciplined approach to learning, and self-management 2. A collaborative reflection and critique that embraced a sense of team ethos and community cohesion, for the first time in a safe environment, as well as a sense of shared purpose and values. Conclusions: The programme helped to identify the impact of leadership on workplace cultures and to begin to embed ways of working that are collaborative, inclusive, participative and celebratory. This unique approach by one organisation to leadership development has enabled medical clinical leaders to embark on a journey of self-transformation. Implications for practice: • An internal model grows clinical leadership capacity across an organisation through peer support and networking, and collective leadership • Investing in a safe, confidential space for clinical leads and other staff groups is a potentially effective strategy for leadership development practice • There is need to develop more skilled critical companions to support leadership, improvement and development activities • Clinical leadership development, informed by practice development methodology, demonstrates the potential to enable transformative and collective leadership to promote person-centred cultures in the workplace [ABSTRACT FROM AUTHOR]

Abstract: An innovative approach for the numerical study of spontaneous adhesion (or stiction) phenomena in Micro-Electro-Mechanical Systems (MEMS) is proposed, based on the use of 3D Finite Element (FE) models. Stiction is a major reliability problem in MEMS which can completely destroy the normal mobility of parts which have the task e.g. to sense the external acceleration in micro-accelerometers or the rotation velocity in micro-gyroscopes. Capillary and van der Waals forces are first selected as the most important sources of stiction; subsequently, these forces are modelled in a simplified way in view of their introduction in a FE model. As a second important ingredient in the proposed modelling approach for spontaneous adhesion, rough surfaces are numerically generated by making use of suitably adapted algorithms originally developed for tribology studies. A complete 3D FE model for two rough surfaces which come at very short distances is thus built and various results showing the modelling capabilities are shown. A comparison with experimental results recently appeared in the literature is proposed. [Copyright &y& Elsevier]

This paper discusses the use of risk and resilience theory to understand how individuals and communities respond to natural disasters that present ongoing developmental challenges to personal and collective well-being. In the past two to three decades, mental health workers have developed numerous disaster relief strategies; while economists have become expert at estimating risk. These develops are explored. [ABSTRACT FROM AUTHOR]

Abstract: Three-dimensional non-contact optical techniques for rapid and accurate mapping of micro-machined surfaces are important for the optoelectronic industry. Interferometry is a well-established technique for 3-D surface profiling. The conventional interferometric surface profilers using a single wavelength offer excellent vertical resolution, but a serious limitation to their use is that they can only handle smooth profiles and step heights less than half a wavelength. In this paper we describe a two-wavelength micro-interferometric setup for 3-D surface profile characterization of smooth as well as rough micro-specimens. The method removes ambiguity associated with the single-wavelength data and also extends the phase measurement range compared to the conventional single-wavelength interferometry. Seven-phase step algorithm is used for quantitative fringe analysis. The design of the system along with experimental results on smooth and rough micro-specimens is presented. [Copyright &y& Elsevier]

Abstract: In this note, we examine the high Péclet number limit of the stationary extended Graetz problem for which two families of real and imaginary eigenvalues are associated, respectively, with a downstream convective relaxation and the upstream diffusive establishment. The asymptotic behavior of both families of eigenvalues is studied, in the limit of large Péclet number and thin wall, which bring to the fore a single parameter dependence, previously mentioned in the literature from numerical investigations [M.A. Cotton, J.D. Jackson, in: R.W. Lewis, K. Morgan (Eds.), Numerical Methods in Thermal Problems, vol. IV, Pineridge Press, Swansea, 1985, pp. 504–515]. The fully developed region is specifically studied thanks to the first eigenvalue dependence on the Péclet number, on the thermal conductivity coefficients and on the diameter ratio of the cylinders. The effective transport between the fluid and the solid is investigated through the evaluation of the fully developed Nusselt number and experimental measurements. [Copyright &y& Elsevier]

Demographic, economic and social conditions developed countries are faced with require a paradigm change for delivering high quality and efficient health services. In that context healthcare systems have to turn towards individualized of patient's care, also called personal care. Interoperability requirements for ubiquitous personalized health services reach beyond current concepts of health information integration among professional stakeholders and related Electronic Patient Records (“e-Health”): Future personal health platforms have particularly to maintain semantic interoperability among systems using different modalities and technologies, different knowledge representation and domain experts' languages as well as different coding schemes and terminologies to include home, personal and mobile systems. The paper introduces the evolving paradigm related to personal health information systems. [ABSTRACT FROM AUTHOR]

Functional and semantic interoperability requirements for ubiquitous personalised health services reach beyond current concepts of health information integration among professional stakeholders and related Electronic Patient Records (“eHealth”): Future health telematics infrastructures have particularly to maintain semantic interoperability among systems using different coding schemes and terminologies and to include home, personal and mobile systems. [ABSTRACT FROM AUTHOR]

The remarkable advances in miniaturization have been achieved largely by the monolithic integration techniques developed by the integrated circuit industry. However, monolithic integration frequently results in compromised performance and for complete systems frequently there is “some assembly required”. Assembly is typically an expensive procedure that is carried out serially either by human hands or by automated machinery. However, with the growing demand for microsystems, there is an opportunity to drastically reduce assembly costs by arraying both the parts and microsystems, so that parallel assembly can be used. This paper describes an approach to parallel assembly that makes use of silicon micro electro mechanical systems that should achieve low assembly costs while maintaining high precision and a clear path to downscaling. [Copyright &y& Elsevier]

This work presents the results of the experimental and theoretical study of the static pull-in of tilting actuation executed by a hybrid levitation micro-actuator (HLMA) based on the combination of inductive levitation and electrostatic actuation. A semi-analytical model to study such a pull-in phenomenon is developed, for the first time, as a result of using the qualitative technique based on the Lagrangian approach to analyze inductive contactless suspensions and a recent progress in the calculation of mutual inductance and force between two circular filaments. The obtained non-linear model, accounting for two degrees of freedom of the actuator, allows us to predict accurately the static pull-in displacement and voltage. The results of modeling were verified experimentally and agree well with measurements. [ABSTRACT FROM AUTHOR]

This paper presents the results of experiments and combined numerical calculations for various kinds of automotive sensors and different microcomponents and microsystems for 'high tech' applications. With growing miniaturization, the 'local' properties of interconnected materials exert a greater influence on the reliability of microcomponents and microsystems than in any macroscopic component. The research team of the author has applied such techniques as acoustic microscopy, laser scanning microscopy, thermography, various kinds of laser field measuring techniques, X-ray stress analysis and the micro-DAC method, combined with FEA field simulation and reliability concepts. Special attention has been given to analysing the thermal fatigue and creep behaviour of solder regions (e.g. solder bumps and micro-solder interconnects) in the near chip regions of microsystem packages and housings. Advanced packaging strategies in automotive applications (e.g. the micromechatronic packaging approach, area array packaging, CSP, etc.) are in the focus of this research. The micro-moiréand micro-DAC techniques are described, using a laser and electron beams for the detection of local micro-deformation fields as well. Different automotive sensors, HF devices and other microcomponents and microsystems have been investigated and evaluated with respect to reliability and lifetime estimation. Crack avoidance strategies have been developed and employed successfully in various applications. Besides the classic concepts of FEA and also stochastic FEM, tools are applied in detail and combined with probabilistic fracture concepts to study the influence of scattering material parameters and of the geometric configuration on reliability estimations as well. The aim is to show that an adequate combination of advanced experimental and simulation approaches leads to reliable results for failure assessment and lifetime predictions of 'high tech' microsystems, e.g. MEMS, in automotive applications. [ABSTRACT FROM AUTHOR]

Through remote forces, levitating micro-actuators completely eliminate mechanical attachment between the stationary and moving parts of a micro-actuator, thus providing a fundamental solution to overcoming the domination of friction over inertial forces at the micro-scale. Eliminating the usual mechanical constraints promises micro-actuators with increased operational capabilities and low dissipation energy. Further reduction of friction and hence dissipation by means of vacuum leads to dramatic increases of performance when compared to mechanically tethered counterparts. In order to efficiently employ the benefits provided by levitation, micro-actuators are classified according to their physical principles as well as by their combinations. Different operating principles, structures, materials and fabrication methods are considered. A detailed analysis of the significant achievements in the technology of micro-optics, micro-magnets and micro-coil fabrication, along with the development of new magnetic materials during recent decades, which has driven the creation of new application domains for levitating micro-actuators is performed. [ABSTRACT FROM AUTHOR]

Abstract: In micro-electromechanical systems (MEMS), coupling of structures through electrostatic forces is a primordial phenomenon. Simulating the dynamics of MEMS and taking into account such strong coupling effects allows one to predict dynamical performance and stability, and is therefore an essential issue in the design of highly effective and reliable devices. Analysis techniques for such systems require special attention in order to provide to the designer accurate and fast tools. We propose a finite element approach (FEM) that properly handles the strong electromechanical coupling in MEMS. In the simulation example of a micro-bridge, we show that such simulation techniques can reveal complex dynamical behaviors of MEMS such as dynamic pull-in. [Copyright &y& Elsevier]