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Highlights: The paper introduces a bioresorbable elastomer, poly(glycolide-co-ε-caprolactone) (PGCL), with remarkable mechanical properties, including high elongation-at-break (< 1300%), resilience, and toughness (75 MJ m−3) for soft and transient electronics. Fabrication of conducting polymers with PGCL yields stretchable, conductive composites for transient electronic devices, functioning reliably under external strains. The study demonstrates the feasibility of a disintegrable electronic suture system with on-demand drug delivery for rapid recovery of post-surgical wounds on soft, time-dynamic tissues or versatile biomedical areas of interest. Substrates or encapsulants in soft and stretchable formats are key components for transient, bioresorbable electronic systems; however, elastomeric polymers with desired mechanical and biochemical properties are very limited compared to non-transient counterparts. Here, we introduce a bioresorbable elastomer, poly(glycolide-co-ε-caprolactone) (PGCL), that contains excellent material properties including high elongation-at-break (< 1300%), resilience and toughness, and tunable dissolution behaviors. Exploitation of PGCLs as polymer matrices, in combination with conducing polymers, yields stretchable, conductive composites for degradable interconnects, sensors, and actuators, which can reliably function under external strains. Integration of device components with wireless modules demonstrates elastic, transient electronic suture system with on-demand drug delivery for rapid recovery of post-surgical wounds in soft, time-dynamic tissues. [ABSTRACT FROM AUTHOR]

This paper presents the design, development, and testing of an IoT-enabled smart stick for visually impaired people to navigate the outside environment with the ability to detect and warn about obstacles. The proposed design employs ultrasonic sensors for obstacle detection, a water sensor for sensing the puddles and wet surfaces in the user's path, and a high-definition video camera integrated with object recognition. Furthermore, the user is signaled about various hindrances and objects using voice feedback through earphones after accurately detecting and identifying objects. The proposed smart stick has two modes; one uses ultrasonic sensors for detection and feedback through vibration motors to inform about the direction of the obstacle, and the second mode is the detection and recognition of obstacles and providing voice feedback. The proposed system allows for switching between the two modes depending on the environment and personal preference. Moreover, the latitude/longitude values of the user are captured and uploaded to the IoT platform for effective tracking via global positioning system (GPS)/global system for mobile communication (GSM) modules, which enable the live location of the user/stick to be monitored on the IoT dashboard. A panic button is also provided for emergency assistance by generating a request signal in the form of an SMS containing a Google maps link generated with latitude and longitude coordinates and sent through an IoT-enabled environment. The smart stick has been designed to be lightweight, waterproof, size adjustable, and has long battery life. The overall design ensures energy efficiency, portability, stability, ease of access, and robust features. [ABSTRACT FROM AUTHOR]

Numerous medical operations employ blood transfusions, requiring X-ray irradiated blood for safety concerns. Current irradiation techniques can be significantly improved by replacing standard visual indicators with wireless dosimeter tags that automate the process, reducing inefficiencies, and eliminating blood wastage. A key requirement of the proposed dosimeter tag is flexible and efficient antennas that can be mounted on blood bags. This paper presents the design of a low-cost inkjet-printed dipole antenna on flexible Kapton substrate for a 2.45 GHz radio frequency identification (RFID) dosimeter tag. The tag is to be used in a lossy blood environment, which can severely affect antenna radiation performance. To mitigate this, the concept of artificial magnetic conductor (AMC) unit cells is investigated for best impedance and gain performance. When integrated with a dipole radiator, the fabricated AMC-backed antenna maintains broadside radiation with gains of 4.1–4.8 dBi under planar and bending conditions, and on a lossy blood bag. In a rectenna configuration, the antenna can power sensors for ranges up to 1 m. Measured output dc voltages up to 1.7 V are achieved across a 25 $\text{k}\Omega $ resistor. This antenna design is flexible, compact, efficient on lossy structures, and suitable for direct integration with biomedical sensing chips. [ABSTRACT FROM AUTHOR]

This paper reports the modelling approach and optimization of a magnetically actuated cell-stretching device. The paper first describes the numerical simulation of the actuation system consisting of a permanent magnet and an electromagnet. The magnetic flux density and magnetic force were verified experimentally over the range of superimposed magnetic flux density from 186 mT to 204 mT. The relative errors for magnetic flux density and magnetic force are 5% and 15%, respectively. This systematic modelling approach provides a reasonable numerical model for optimizing the electromagnetic actuator of the cell-stretching device. The induced actuation force was then coupled with the structural analysis of the cell-stretching device to determine the acceptable distance between the two magnets. The results suggested that this actuation system is capable of precisely predicting the behavior of our existing cell-stretching device. [ABSTRACT FROM AUTHOR]

This paper presents the design and implementation of a cantilever array device using a multi-user MEMS process for emerging point-of-care (PoC) diagnostic technologies. Each cantilever is incorporated with two capacitive sensing electrodes for the measurement of its beam deflection. A custom-made multichannel interface readout circuit was also developed using off-the-shelf elements for capacitance recording and data acquisition purposes. Herein, we demonstrate and discuss the functionality of the proposed capacitive cantilever array platform using interferometry and non-invasive rapid air-based characterization techniques. Based on simulation and experimental results, the proposed cantilever based platform can accurately measure μN-scale forces applied on each cantilever. The applicability of the proposed cantilever system was successfully investigated for PoC lung diagnostic purposes. Based on these results, the proposed system shows significant promise for use as an emerging free breathing measurement system for continuous assessment of respiratory health. [ABSTRACT FROM AUTHOR]

In this work, the selective laser melting (SLM) of CoCr alloy powder for producing cardiovascular stents is investigated. The paper aims to assess the feasibility of producing a CoCr stent precursor through SLM as an alternative method to the conventional manufacturing cycle, which is based on microtube production and consecutive laser microcutting. Design rules for manufacturability are investigated, and a simple prototype design for additive manufacturing is proposed. The SLM process is investigated with an industrial system that utilises pulsed wave emission. Different scan strategies, namely hatching and concentric scanning, were used. Strut thickness and roughness, as well as chemical composition, were analysed. Representative conditions were further analysed by microhardness measurements and X-ray micro computed tomography. Electrochemical polishing was applied to assess the feasibility of surface finishing. The results show that SLM can be considered as a substitute operation to microtube manufacturing and laser microcutting for shaping precursors in stent manufacturing. Prototype stents with acceptable geometrical accuracy were achieved and surface quality could be improved through electrochemical polishing. The chemical composition remained unvaried, with a marginal increase in the oxide content. [ABSTRACT FROM AUTHOR]

Functionally graded materials (FGMs) are innovative materials whose composition and/or microstructure gradually vary in space according to a designed law. As a result, also the properties gradually vary in space, so as to meet specific non-homogeneous service requirements without any abrupt interface at the macroscale. FGMs are emerging materials for orthopedic prostheses, since the functional gradient can be adapted to reproduce the local properties of the original bone, which helps to minimize the stress shielding effect and, at the same time, to reduce the shear stress between the implant and the surrounding bone tissue, two critical prerequisites for a longer lifespan of the graft. After a brief introduction to the origin of the FGM concept, the review surveys some representative examples of graded systems which are present in nature and, in particular, in the human body, with a focus on bone tissue. Then the rationale for using FGMs in orthopedic devices is discussed more in detail, taking into account both biological and biomechanical requirements. The core of the paper is dedicated to two fundamental topics, which are essential to benefit from the use of FGMs for orthopedic applications, namely (1) the computational tools for materials design and geometry optimization, and (2) the manufacturing techniques currently available to produce FGM-based grafts. This second part, in its turn, is structured to consider the production of functionally graded coatings (FGCs), of functionally graded 3D parts, and of special devices with a gradient in porosity (functionally graded scaffolds). The inspection of the literature on the argument clearly shows that the integration of design and manufacturing remains a critical step to overpass in order to achieve effective FGM-based implants. [ABSTRACT FROM AUTHOR]

Surface stress biosensor is one of the most promising ways to solve some of the problems concerning the increasing need to develop highly sensitive, fast and economic methods of analysis in medical diagnostics and high throughput screening of bioprocess for candidate drug screening and therapeutic effect monitor. Micro cantilever and micro membrane are two commonly used transducer structures of surface stress biosensors. The physical transducer often determines the limits of detection. Micro membrane-type surface stress biosensors can improve the signal-to-noise ratio. This paper presents PDMS (polydimethylsiloxane) micro membrane capacitance-type surface stress biosensors. The whole analyte-induced surface stress on the micro membrane is efficiently transduced to the membrane deflection and detected as the capacitive signal. The detection to Staphylococcus aureus ( S. aureus ) is realized based on this PDMS micro-membrane capacitance-type surface stress biosensor. For the state of S. aureus , the higher capacitive value corresponding to the less live S. aureus concentration, the maximum resolution of the biosensor is about 0.73 fF/bacterium in this study. S. aureus test result proves that the biosensor can be used as the device to examine the medical treatment effect. The biosensor is easy to form an ordered array, which has more potential biological and medical applications. [ABSTRACT FROM AUTHOR]

This paper presents an implantable encapsulated structure that can deliver localized heating (hyperthermia) and controlled concentrations of prodigiosin (a cancer drug) synthesized by bacteria (Serratia marcesce (subsp. marcescens)). Prototypical Poly-di-methyl-siloxane (PDMS) packages, containing well-controlled micro-channels and drug storage compartments, were fabricated along with a drug-storing polymer produced by free radical polymerization of Poly(N-isopropylacrylamide)(PNIPA) co-monomers of Acrylamide (AM) and Butyl-methacrylate (BMA). The mechanisms of drug diffusion of PNIPA-base gels were elucidated. Scanning Electron Microscopy (SEM) was also used to study the heterogeneous porous structure of the PNIPA-based gels. The release exponents, n, of the gels were found to between 0.5 and 0.7. This is in the range expected for Fickian (n = 0.5). Deviation from Fickian diffusion was also observed (n > 0.5) diffusion. The gel diffusion coefficients were shown to vary between 2.1 x 10-12 m²/s and 4.8 x 10-6 m²/s. The implications of the results are then discussed for the localized treatment of cancer via hyperthermia and the controlled delivery of prodigiosin from encapsulated PNIPA-based devices. [ABSTRACT FROM AUTHOR]

Electrochemotherapy (ECT) is a local anticancer treatment for superficial tumors which involves the administration of a chemotherapeutic drug followed by short, highvoltage pulses. Incipient clinical experience with breast cancer patients are encouraging, with a local complete response rate ranging from 50 to 90%. However, since many patients present with multiple or widespread metastases, ECT, despite its high local antitumor efficacy, need to be applied several times in order to complete treatment delivery or maintain tumor control during the follow-up. In this paper, we propose the prototype of a new grid electrode aimed at the improvement of ECT application. The device is suitable for treating large, tumor-infiltrated skin surfaces as in breast cancer patients with chest wall metastases after mastectomy. According to our tests in different in vitro models, the new device allows to apply the voltage pulses more quickly and homogeneously when compared with standard pulse applicators. This technical advancement holds promise for improving ECT outcome and, hopefully, for sparing a number of patients from the need of multiple treatments. [ABSTRACT FROM AUTHOR]

Abstract: Micropumps have gained a great potential to be applied as biomedical devices and micro systems. Because of low driven voltage, flexible operation, and self sensing ability, the ionic polymer metal composite (IPMC) material has been used as diaphragm of micropumps. This paper presents a novel design of IPMC diaphragm which helps to produce larger deformation and increase the durability of IPMC actuator. Unlike the conventional design of using a single piece of IPMC material clamped at all edges, we use several IPMC actuators (clamped at single edge) to drive elastic thin films. By eliminating the edge constrains for IPMC actuators, the new diaphragm can provide significantly larger deformation. Moreover, new design separates the IPMC from the pumping fluid and thus allows solvent to cover the IPMC and maintain long operating duration. An incorporation of physical induced stress model of IPMC actuators and the visual ANSYS environment is proposed to analyze the characteristic of the proposed diaphragms in comparison with the conventional one. Experiments have also been carried out to demonstrate the effectiveness of proposed model. Experimental results show that the new diaphragm design can produce deformation up to 0.4mm and maintain stable operation over 35min corresponding to a 3V–0.05Hz input signal, while the conventional design can produce only 0.2mm in deformation and the pumping performance decreases rapidly after 8min. [Copyright &y& Elsevier]

Abstract: The possibility of employing graphene sheets as a potential candidate for the construction of biofuel cells is reported in this paper. Initially, graphene sheets were chemically synthesized and characterized by surface characterization techniques. Following this, graphene was employed to fabricate the anode and cathode in the biofuel cell. The anode of the biofuel cell consists of a gold electrode on which we co-immobilized graphene – glucose oxidase using silica sol–gel matrix. Voltammetric measurements were conducted to quantitatively evaluate the suitability of employing graphene sheets as an electrode dopant and its performance was compared with single walled carbon nanotubes (SWCNTs). The cathode of the biofuel cell was constructed in a similar method except that graphene was co-immobilized with bilirubin oxidase. Finally, two membraneless enzymatic biofuel cells, one using graphene sheets and the other using SWCNTs, were constructed and their performances were compared. Upon comparison, graphene based biofuel cell exhibited a maximum power density of about 24.3±4μW (N =3), which is nearly two times greater than that of the SWCNTs biofuel cell, and the performance of the graphene biofuel cell lasted for 7 days. [Copyright &y& Elsevier]

In dental medicine, the study of mandibular movement has an important role in oral rehabilitation as it allows diagnosis of pathologies in the temporomandibular joint and the definition of adequate treatment plans. In this paper, a new device specially developed for the acquisition and analysis of 3D mandibular movement is presented. A facial arc is adopted as its main support structure and electromagnetic sensors are employed to acquire the mandibular movement. A neural network is used to transform the electrical signals output by the sensors into 3D Cartesian coordinates. A custom-made computer application is developed to display and analyse the movement acquired. The device is shown to be easy to use, comfortable for patients and capable of being produced at an affordable price. [ABSTRACT FROM AUTHOR]

Kaiser Permanente developed its approach to compliance with the privacy and security rules of the Health Insurance Portability and Accountability Act (HIPAA) of 1996 as part of its national, enterprise-wide approach to health information system design, purchasing, implementation and management. Widely perceived as a self-directed, leader in health information security, its experience in HIPAA compliance provides lessons in mobilizing and changing large, stable organizations in response to an externally imposed mandate. While Kaiser approached HIPAA primarily as an effort in certifying compliance, it saw HIPAA as an opportunity to investigate its security business processes and information technology. This paper explains how Kaiser evaluated over 3000 computer systems along with hundreds of types of biomedical devices and made the decisions necessary to bring them into compliance with the HIPAA Security Standard. [Copyright &y& Elsevier]

This paper presents the study of an implantable biomedical device for the localized released of chemotherapeutic drugs and the controlled heating of surrounding tumor tissue to enable cancer treatment via a hyperthermia and chemotherapy combination. The coupling of magnetic induction, heat transfer, and mass diffusion concepts used to model temperature changes and drug release from the biomedical device to a surrounding environment that mimics breast tumor tissue and normal breast tissue. The predictions of temperature change in the residual tumor cells and the normal breast tissue show that when an excitation current of 25 mA supplied to the device generates heat that required to kill the residual cancer cells without damaging the nearby healthy tissue. Also, the predictions of prodigiosin concentration released from the biomedical device into selected depths in the breast phantom model show that the residual tumor has a higher concentration than the healthy tissue. The proposed system proved capable for prolonged drug delivery and temperature rise of tumor to therapeutic values for effective localize cancer treatment. [ABSTRACT FROM AUTHOR]