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Piezoelectric materials, a type of “smart” material that generates electricity while deforming and vice versa, have been used extensively for many important implantable medical devices such as sensors, transducers, and actuators. However, commonly utilized piezoelectric materials are either toxic or nondegradable. Thus, implanted devices employing these materials raise a significant concern in terms of safety issues and often require an invasive removal surgery, which can damage directly interfaced tissues/organs. Here, we present a strategy for materials processing, device assembly, and electronic integration to 1) create biodegradable and biocompatible piezoelectric PLLA [poly(l-lactic acid)] nanofibers with a highly controllable, efficient, and stable piezoelectric performance, and 2) demonstrate device applications of this nanomaterial, including a highly sensitive biodegradable pressure sensor for monitoring vital physiological pressures and a biodegradable ultrasonic transducer for blood–brain barrier opening that can be used to facilitate the delivery of drugs into the brain. These significant applications, which have not been achieved so far by conventional piezoelectric materials and bulk piezoelectric PLLA, demonstrate the PLLA nanofibers as a powerful material platform that offers a profound impact on various medical fields including drug delivery, tissue engineering, and implanted medical devices.

The peripheral nervous system (PNS) is an attractive target for modulation of afferent input (e.g., nociceptive input signaling tissue damage) to the central nervous system. To advance mechanistic understanding of PNS neural encoding and modulation requires single-unit recordings from individual peripheral neurons or axons. This is challenged by multiple connective tissue layers surrounding peripheral nerve fibers that prevent electrical recordings by existing electrodes or electrode arrays. In this study, we developed a novel microelectrode array (MEA) via silicon-based microfabrication that consists of 5 parallel hydrophilic gold electrodes surrounded by silanized hydrophobic surfaces. This novel hydrophilic/hydrophobic surface pattern guides the peripheral nerve filaments to self-align towards the hydrophilic electrodes, which dramatically reduces the technical challenges in conducting single-unit recordings. We validated our MEA by recording simultaneous single-unit action potentials from individual axons in mouse sciatic nerves, including both myelinated A-fibers and unmyelinated C-fibers. We confirmed that our recordings were single units from individual axons by increasing nerve trunk electrical stimulus intensity, which did not alter the spike shape or amplitude. By reducing the technical challenges, our novel MEA will likely allow peripheral single-unit recordings to be adopted by a larger research community and thus expedite our mechanistic understanding of peripheral neural encoding and modulation.

BACKGROUND: The aim of this research was to engineer solid dispersion lipid particles (SD-SLs) in which a solid dispersion (SD) was encapsulated to form the core of solid lipid particles (SLs), thereby achieving an efficient enhancement in the dissolution of a poorly water-soluble drug. METHODS: Ultrasonication was introduced into the process to obtain micro/nanoscale SLs. The mechanism of dissolution enhancement was investigated by analysing the crystalline structure, molecular interactions, and particle size of the formulations. RESULTS: The drug release from the SD-SLs was significantly greater than that from the SD or SLs alone. This enhancement in drug release was dependent on the preparation method and the drug-to-polymer ratio of the SD. With an appropriate amount of polymer in the SD, the solidification method had the potential to alter the drug crystallinity to an amorphous state, resulting in particle uniformity and molecular interactions in the SD-SLs. CONCLUSIONS: The proposed system provides a new strategy for enhancing the dissolution rate of poorly water-soluble drugs and further improving their bioavailability.

Recently, reverse supply chain (RSC)has received significant attention from researchers, governments and industries. Most current studies assumed that parameters in RSC are deterministic or known in advance. In addition, risk and incentive elements in RSC models are neglected. Risk factors normally come from transportation and treatment processes which can lead to the increasing cost of the RSC system. Incentive fee can support consumers to return their end-of-life products. This research aims to minimize the total cost of an RSC model incorporating risk and incentive factors while some key parameters in the model are represented by fuzzy numbers. Fuzzy mathematical programming is utilized to solve the problem and find the optimal locations of facilities as well as the flow of materials in the network. A numerical example of electronic waste (e-waste)is investigated to demonstrate the usefulness of the proposed model. This study can provide significant implications since it can support managers to determine important strategic decisions in the design of an effective RSC model towards sustainable development. Refereed/Peer-reviewed

Due to fast-paced advancements in technology and innovation, new product development (NPD) has received great attention from industries. This development can assist companies to maintain their business's competitive edge. However, NPD task is a risk and complex process which is normally handled by NPD teams. These teams are currently lacking effective procedures to enhance their efforts to develop truly innovative products. Hence, this paper aims to develop a new systematic approach for new product development by integrating TRIZ principles into the Design for six sigma methodology. The proposed method will be effective in triggering creative concepts for innovative products and applied for a wide range of products. Refereed/Peer-reviewed

Approximately 10-15% of the population worldwide is affected by Chronic Kidney Diseases (CKD). The most severe form of CKD is an end-stage renal disease (ESRD) and the treatment for ESRD is either by dialysis or kidney transplantation. Around 30% of patients with ESRD have a willing living donor in time of transplant, but their donors are incompatible due to either blood group incompatibility or human leucocyte antigen sensitization of the recipient against the donor. Kidney Exchange Program (KEP) is a policy that aims to solve this issue by matching incompatible pairs of donors and recipients with other incompatible pairs, thus increasing the chance of both pairs of receiving a kidney. Most existing research applied the exact method to solve the KEP models, but this method has some drawbacks. This research aims to propose a Genetic Algorithms (GA) approach in order to maximize the potential number of transplants in KEP. The proposed method counts and extracts all the cycles and chains prior to starting the algorithm. This step will significantly decrease the computing time needed to run the algorithm, which is one of the drawbacks of using GA. The result showed that solving the KEP by GA approach has the potential of achieving optimal results with 88.8% matching efficiency. Refereed/Peer-reviewed

Along with the search for new therapeutic agents, advanced formulation and fabrication of drug carriers are required for better targeting, sensing, and responding to environmental stimuli as well as maximizing treatment efficiency. The emergence of intelligent therapeutics involves the use of functional biomaterials to mimic biological system for prolonged circulation and to work harmoniously with the body. One of the main concerns lies in the feasibility of creating systems with well-defined architectures including size, shape, components, and functionality. This review provides an overview regarding current challenges and potential of manufacturing and fabrication of biomaterials at small scales for various biomedical applications. Accordingly, novel lithography-based fabrication approaches are introduced together with their remarkable applications. Besides being popular in microelectronics, lithography techniques have demonstrated a great potential use for drug delivery, tissue engineering, and diagnostic tools.

Marine environment exhibits an enormous diversity of organisms which contains an abundant source of polysaccharides. As polymer matrix carriers, marine-based polymers possess several valuable properties including high stability, non-toxicity, hydrophilicity, biodegradability, with low production cost. Despite notable biological activities of these natural polymers, there are certain limitations in exploring their functions in applications of nano-sized drug delivery systems. The review aims to demonstrate exceptional characteristics of marine-based polymers including fucoidan, alginate, carrageenan, hyaluronic acid, chondroitin sulfate, and chitosan as well as provide perspectives of current publications on their nanoparticle formulations for biomedical applications.