Home-based Detection and Prediction of Diabetic Foot Ulcers at EarlyStage Using Sensor Technology and Supervised Learning

For years, foot ulcers linked with diabetes mellitus and neuropathy have significantly impacted diabetic patients health-related quality of life (HRQoL). Diabetes foot ulcers impact 15% of all diabetic patients at some point in their lives. The facilities and resources used for DFU detection and treatment are only available at hospitals and clinics, which results in the unavailability of feasible and timely detection at an early stage. This necessitates the development of an at-home DFU detection system that enables timely predictions and seamless communication with users, thereby preventing amputations due to neglect and severity. This paper proposes a feasible system consisting of three major modules: an IoT device that works to sense foot nodes to send vibrations onto a foot sole, a machine learning model based on supervised learning which predicts the level of severity of the DFU using four different classification techniques including XGBoost, K-SVM, Random Forest, and Decision tree, and a mobile application that acts as an interface between the sensors and the patient. Based on the severity levels, necessary steps for prevention, treatment, and medications are recommended via the application.     

Influence of solid lubricants and fibre reinforcement on wear behaviour of polyethersulphone

Polyethersulphone (PES), is an amorphous, brittle and high temperature engineering thermoplastic. Two composites of PES containing short glass fibres (GF) and solid lubricants viz. PTFE and MoS₂; and two composites containing short carbon fibre (CF) [30% and 40%] were selected for the present studies. Compositional analysis of selected materials was done with various techniques such as gravimetry, solvent extraction and thermal analysis viz. thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). These materials were studied for adhesive and abrasive wear performance by sliding against a mild steel disc and silicon carbide abrasive paper respectively, under different loads. It was observed that GF reinforcement along with incorporation of solid lubricants (PTFE and MoS₂) enhanced the wear performance of PES by an order of two. In the case of solid lubricants, PTFE proved to be more beneficial than MoS₂. CF reinforcement, however, proved to be the most effective in enhancing wear performance of PES. PES reinforced with 40% CF exhibited a specific wear rate in the order of 10⁻¹⁶m³/Nm which is considered to be very good for the thermoplastic composite. In the case of abrasive wear behaviour, however, incorporation of fibres or solid lubricants deteriorated the performance of the neat matrix. SEM was employed to investigate the wear mechanisms.     

Influence of molecular weight on performance properties of polyethersulphone and its composites with carbon fabric

The effect of molecular weight (MW) of a polymer on the wettability of fibers and its influence on the performance properties need to be addressed in detail. Specialty polymer, viz. polyethersulphone (PES), with varying MW was selected as a matrix material to develop the composites with carbon fabric (CF). Since carbon fiber is inert towards the matrix, cold remote nitrogen–oxygen plasma (CRNOP) treatment was employed to improve its chemical reactivity, by incorporating functional groups to promote the fiber–matrix adhesion. Evaluation of mechanical and sliding wear properties of polymers and composites led to the conclusion that the CRNOP treatment was beneficial to enhance performance properties. The MW and MFI have inverse relation. MW proved to be a controlling parameter for pristine polymers while melt flow index (MFI) was the decisive parameter for the performance of composites. Perforations and increased roughness on the treated carbon fiber, as observed by the field emission scanning electron microscopy (FESEM), were responsible for the improved fiber–matrix adhesion and hence performance properties.     

Tissue Engineering of Cartilage Using a Random Positioning Machine

Articular cartilage is a skeletal tissue of avascular nature and limited self-repair capacity. Cartilage-degenerative diseases, such as osteoarthritis (OA), are difficult to treat and often necessitate joint replacement surgery. Cartilage is a tough but flexible material and relatively easy to damage. It is, therefore, of high interest to develop methods allowing chondrocytes to recolonize, to rebuild the cartilage and to restore joint functionality. Here we studied the in vitro production of cartilage-like tissue using human articular chondrocytes exposed to the Random Positioning Machine (RPM), a device to simulate certain aspects of microgravity on Earth. To screen early adoption reactions of chondrocytes exposed to the RPM, we performed quantitative real-time PCR analyses after 24 h on chondrocytes cultured in DMEM/F-12. A significant up-regulation in the gene expression of IL6, RUNX2, RUNX3, SPP1, SOX6, SOX9, and MMP13 was detected, while the levels of IL8, ACAN, PRG4, ITGB1, TGFB1, COL1A1, COL2A1, COL10A1, SOD3, SOX5, MMP1, and MMP2 mRNAs remained unchanged. The STRING (Search Tool for the Retrieval of Interacting Genes/Proteins) analysis demonstrated among others the importance of these differentially regulated genes for cartilage formation. Chondrocytes grown in DMEM/F-12 medium produced three-dimensional (3D) spheroids after five days without the addition of scaffolds. On day 28, the produced tissue constructs reached up to 2 mm in diameter. Using specific chondrocyte growth medium, similar results were achieved within 14 days. Spheroids from both types of culture media showed the typical cartilage morphology with aggrecan positivity. Intermediate filaments form clusters under RPM conditions as detected by vimentin staining after 7 d and 14 d. Larger meshes appear in the network in 28-day samples. Furthermore, they were able to form a confluent chondrocyte monolayer after being transferred back into cell culture flasks in 1 g conditions showing their suitability for transplantation into joints. Our results demonstrate that the cultivation medium has a direct influence on the velocity of tissue formation and tissue composition. The spheroids show properties that make them interesting candidates for cellular cartilage regeneration approaches in trauma and OA therapy.     

Development of a gelatin-g-poly(acrylic acid-co-acrylamide)–montmorillonite superabsorbent hydrogels for in vitro controlled release of vitamin B12

Gelatin (Ge)-g-poly(acrylic acid-co-acrylamide) and montmorillonite (MMT)-clay-based nanocomposite hydrogels were fabricated to study the controlled release of vitamin B₁₂. Polymeric hydrogels were characterized with Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). FTIR spectroscopy confirmed the grafting of partially neutralized acrylic acid on a Ge backbone. The incorporation of MMT fillers inside the nanocomposite hydrogels and their increased crystallinity were established by XRD analysis. The rough surface morphologies of the composite hydrogels shown by SEM resulted from the assimilation of MMT inside the same. TEM confirmed the formation of nanosized composites. The average length and width of the MMT platelets were found to be 184.37 and 20.48 nm, respectively. The maximum swelling of the hydrogel was 375 g/g, and the results were established with Design-Expert software. The biodegradability of the nanocomposite increased in comparison to that of the copolymer hydrogel. Biocompatibility and cytotoxicity studies were also performed. During different time intervals, the controlled release of vitamin B₁₂ in artificial gastric fluid (AGF) and artificial intestinal fluid (AIF) was evaluated with a UV–visible spectrophotometer; this resulted in different controlled release curves. The release in AGF was 42%, and in AIF, the cumulative release was 80% over 6 h. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47596.     

Passive direct formic acid microfabricated fuel cells

This paper reports on microscale silicon-based direct formic acid fuel cells (Si-DFAFCs) in which the fuel and the oxidant are supplied to the electrodes in a passive manner. Passive delivery of fuel and oxidant eliminates the need for ancillary components and associated parasitic losses. In this Si-DFAFC, an aqueous solution of formic acid is in direct contact with a Pd- or Pt-based anode and a Pt-based cathode is exposed to either a forced oxygen stream or quiescent air. In the presence of a forced oxygen flow on the cathode side the cell with Pd catalyst on the anode delivers a maximum power density of about 30 mW cm⁻² at room temperature, limited mostly by mass transfer at the anode, while in an all-passive mode (quiescent air on the cathode side) a maximum power density of 12.3 mW cm⁻² is obtained, limited by oxygen transport. This all-passive Si-DFAFC is fabricated using processes that are post-CMOS compatible, and thus can be integrated directly with envisioned MEMS applications, such as small sensors and actuators.     

Edible coating materials—their properties and use in the fortification of rice with folic acid

This study investigated the technical feasibility of adding folic acid on to rice and coating with edible polymers. The coating solutions were cast into film and their properties were investigated. A concentrated premix of rice was prepared in a rotating coating pan by spraying first with folic acid solution, and then with polymer solutions and drying. The fortified rice premixes were evaluated for washing and cooking losses. The loss of folic acid in washing was lowest in rice premixes coated with ethyl cellulose followed by pectin, composite mixtures of locust bean and other coating materials with highest loss in gum arabic coated rice. No edible polymer could satisfactorily retain folic acid during boiling in excess water. Edible polymers failed to mask the yellow color of folic acid and additional masking agent was needed. The premixes had a higher water uptake ratio than raw milled rice had. Triangle tests did not show any significant difference (=0.05) between the sensory qualities of cooked fortified rice and raw milled rice.