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The combination of graphene (G) and multi-walled carbon nanotubes (MWCNTs) creates three-dimensional hybrid structures particularly suitable as next-generation electrical interface materials. Nevertheless, efficient mixing of the nanopowders is challenging, unless previous disaggregation and eventual surface modification of both is reached. To avoid use of solvents and multistep purification process for synthesis of stable G/MWCNTs hybrids, herein, a novel dry method based on an air sonication process was used. Taking advantage from the vigorous turbulent currents generated by powerful ultrasonication in air that induces strong thermal convection or radiation to and from the particles, it simultaneously ensures disentanglement of the large MWCNT bundles and G exfoliation and their only mild surface modifications. By changing the ratio between MWCNTs and G, a range of hybrids was obtained, different in surface morphology and chemistry. These hybrids have shown great potential as sensing material for designing mass-based sensors for toxic gases and chemiresistor for vapors detection.A promising alternative to current treatment options for degenerative conditions of the temporomandibular joint (TMJ) is cartilage tissue engineering, using 3D printed scaffolds and mesenchymal stem cells. Gelatin, with its inherent biocompatibility and printability has been proposed as a scaffold biomaterial, but because of its thermoreversible properties, rapid degradation and inadequate strength it must be crosslinked to be stable in physiological conditions. The aim of this study was to identify non-toxic and effective crosslinking methods intended to improve the physical properties of 3D printed gelatin scaffolds for cartilage regeneration. Dehydrothermal (DHT), ribose glycation and dual crosslinking with both DHT and ribose treatments were tested. The crosslinked scaffolds were characterized by chemical, mechanical, and physical analysis. The dual-crosslinked scaffolds had the highest degree of crosslinking and the greatest resistance to hydrolytic and enzymatic degradation. Compared to the dual-crosslinked group, the ribose-crosslinked scaffolds had thinner printed strands, larger pore surface area and higher fluid uptake. The compressive modulus values were 2 kPa for ribose, 37.6 kPa for DHT and 30.9 kPa for dual-crosslinked scaffolds. None of the crosslinking methods had cytotoxic effects on the seeded rat bone marrow-derived mesenchymal stem cells (rBMSC). After 4 and 7 d, the dual-crosslinked scaffolds exhibited better cell proliferation than the other groups. Although all scaffolds supported chondrogenic differentiation of rBMSC, dual-crosslinked scaffolds demonstrated the lowest expression of the hypertrophy-related collagen 10 gene after 21 d. The results show that 3D printed gelatin scaffolds, when dually crosslinked with ribose and DHT methods, are not toxic, promote chondrogenic differentiation of rBMSC and have potential application in tissue engineering of TMJ condylar cartilage.Objective.To restore central vision in patients with atrophic age-related macular degeneration, we replace the lost photoreceptors with photovoltaic pixels, which convert light into current and stimulate the secondary retinal neurons. Clinical trials demonstrated prosthetic acuity closely matching the sampling limit of the 100μm pixels, and hence smaller pixels are required for improving visual acuity. However, with smaller flat bipolar pixels, the electric field penetration depth and the photodiode responsivity significantly decrease, making the device inefficient. Smaller pixels may be enabled by (a) increasing the diode responsivity using vertical p-n junctions and (b) directing the electric field in tissue vertically. Here, we demonstrate such novel photodiodes and test the retinal stimulation in a vertical electric field.Approach.Arrays of silicon photodiodes of 55, 40, 30, and 20μm in width, with vertical p-n junctions, were fabricated. The electric field in the retina was directed vertically using a co.Advanced biomaterials have produced a significant impact on healthcare by improving the quality of life of people with disabilities. Biomaterials are immensely used in tissue engineering, wound healing applications, and delivery of cancer targeted therapeutics. Biocompatibility and cytotoxicity screening of biomaterials on cell culture systems is the first step before their in vivo testing in animal models and subsequent clinical trials. Direct use of biomaterials on animals may create technical challenges as well as ethical concerns. In order to avoid the ethical concerns of animal use, many non-animal models such as stem cell cultures are being developed and utilized for testing their safety. However, due to several limitations including the inability to recapitulate the complex in vivo microenvironment, the application of stem cell cultures is limited. However, properties of stem cells such as their self-renewal and ability to differentiate into various cell lineages like hepatocytes, cardiomyocytes, and neural cells make them an ideal candidates for in vitro screening studies. Furthermore, the application of stem cells may overcome the challenges associated with the inability to develop a complex heterogeneous tissue using primary cells. Currently, Embryonic Stem Cells (ESCs), Adult Stem Cells (ASCs), and Induced Pluripotent Stem Cells (iPSCs) are being used as in vitro preliminary biomaterials testing models with demonstrated advantages over mature primary cell or cell line based in vitro models. Rocaglamide HSP (HSP90) inhibitor This review discusses the current status and future directions of in vitro stem cell-based cultures and their derivatives such as spheroids and organoids for the screening of their safety before their application to animal models and human in translational research.Objective. Bioimpedance devices are commonly used to assess health parameters and track changes in body composition. However, the cross-sectional agreement between different devices has not been conclusively established. Thus, the objective of this investigation was to examine the agreement between raw bioelectrical variables (resistance, reactance, and phase angle at the 50 kHz frequency) obtained from three bioimpedance analyzers.Approach. Healthy male (n = 76, mean ± SD; 33.8 ± 14.5 years; 83.9 ± 15.1 kg; 179.4 ± 6.9 cm) and female (n = 103, mean ± SD; 33.4 ± 15.9 years; 65.6 ± 12.1 kg; 164.9 ± 6.4 cm) participants completed assessments using three bioimpedance devices supine bioimpedance spectroscopy (BIS), supine single-frequency bioelectrical impedance analysis (SFBIA), and standing multi-frequency bioelectrical impedance analysis (MFBIA). Differences in raw bioelectrical variables between the devices were quantified via one-way analysis of variance for the total sample and for each sex. Equivalence testing was used to determine equivalence between methods.