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Electro-active scaffolds play an important role in bone tissue engineering applications, serving as physical substrates for cell proliferation and osteogenic differentiation, ultimately realizing new bone regeneration. This paper discusses a novel strategy to synthesize graphene through laser-induced surface doping, using bone collagen as the carbon source, serving as a key functional filler to be combined with biocompatible, biodegradable poly(ε-caprolactone) (PCL), for the fabrication of the next generation electro-active bone tissue engineering scaffolds. Scaffolds are fabricated through material-extrusion additive manufacturing. The developed graphene is proven to present a significant enhancement effect on surface and mechanical properties over the conventional graphene material. [ABSTRACT FROM AUTHOR]

Abstract: (ZrB2+3Y-ZrO2)/BN composites were fabricated by hot-pressing with different contents of 3Y-ZrO2 ranging from 0 to 30vol%. The mechanical properties and thermal shock resistance of composites were systematically investigated. The mechanical properties of the composites exhibit a gradual degradation while the thermal shock resistance is improved with the increasing ZrO2 content. The flexural strength and fracture toughness of 30vol% ZrO2/BN composite are 183MPa and 3.80MPam1/2, respectively. The residual strength ratio claims a slight decline to the lowest value of 86.8% after thermal shock, which is improved mainly due to the lower elastic modulus and higher ratio of fracture toughness to flexural strength with increasing ZrO2 content. Furthermore, when temperature difference ranges from 1100 up to 1400°C, the residual flexural strength of the composites increases, which is attributed to the self-healing of cracks and the thermal-barrier effect of the oxide layer. [Copyright &y& Elsevier]

The TRPM (transient receptor potential melastatin) family belongs to the superfamily of TRP cation channels. The TRPM subfamily is composed of eight members that are involved in diverse biological functions such as temperature sensing, inflammation, insulin secretion, and redox sensing. Since the first cloning of TRPM1 in 1998, tremendous progress has been made uncovering the function, structure, and pharmacology of this family. Complete structures of TRPM2, TRPM4, and TRPM8, as well as a partial structure of TRPM7, have been determined by cryo-EM, providing insights into their channel assembly, ion permeation, gating mechanisms, and structural pharmacology. Here we summarize the current knowledge about channel structure, emphasizing general features and principles of the structure of TRPM channels discovered since 2017. We also discuss some of the key unresolved issues in the field, including the molecular mechanisms underlying voltage and temperature dependence, as well as the functions of the TRPM channels' C-terminal domains. [ABSTRACT FROM AUTHOR]

Carbon-based materials have recently attracted tremendous attention for their applications in highly sensitive wearable devices for human motion monitoring. Embedding rare metal nanoparticles such as Au, Ag, and Pt has been proved to significantly improve the sensitivity of the carbon-based strain sensors. However, the existing method to prepare nanoparticles usually involves multi-step, time-consuming procedures. Here, we report a facile one-step laser process to synthesize porous 3D graphene structures embedded with Pt nanoparticles. This is achieved by irradiating an ultraviolet (355 nm) picosecond laser on a film formed with a mixture of polybenzimidazole (PBI) and Pt(acac) 2 solution to simultaneously induce the formation of graphene and reduction of the Pt precursor. The assembled strain sensor with loaded Pt nanoparticles in laser-induced graphene (Pt/LIG) demonstrates ultra-high sensitivity (a gauge factor, GF max ≈ 489.3) and a wide strain range up to 20%. Additionally, the strain sensor with an optimized concentration of Pt(acac) 2 has low hysteresis, minor lag errors, and a highly stable response (>5000 cycles). Various human motion signals are detected, from subtle physical activities (including chewing muscles movement, pulse beating) to large-scale limb track (finger bending, knee movement, and waist extending). This one-step laser process is facile, rapid, and potentially scalable for the mass production of high-performance wearable strain sensors. [Display omitted] • A one-step laser process to synthesize 3D graphene loaded with Pt nanoparticles. • Strain sensor with Pt/LIG showing ultra-high sensitivity (GF max ≈ 489.3). • Strain sensor showing minor lag errors and stable response (>5000 cycles). • Reliable human motion signal detection from subtle activities to limb track. • Facile, rapid and potentially scalable laser process for mass production. [ABSTRACT FROM AUTHOR]

In this paper, an ultra-wideband, angle and polarization-insensitive laser assisted graphene metamaterial absorber is presented. The design consists of double graphene resistive layers with the combination of three dielectric substrates. The graphene imbedded nano-magnetic material Fe 3 O 4 has been synthesisedby laser direct writing technology, which demonstrates a high degree of uniformity with deviations less than 6% for different designed values of sheet resistance. Numerical simulation and analytical studies were carried out in order to analyze the absorption mechanism. The measured results confirm that the absorber operates from 1.32 to 17.9 GHz with over 90% absorptivity. The absorber achieves 173% fractional absorption bandwidth with a thickness of 0.068λ L. [Display omitted] [ABSTRACT FROM AUTHOR]

The Col1a2 +/ G610C knock-in mouse, models osteogenesis imperfecta in a large old order Amish family (OOA) with type IV OI, caused by a G-to-T transversion at nucleotide 2098, which alters the gly-610 codon in the triple-helical domain of the α2(I) chain of type I collagen. Mineral and matrix properties of the long bones and vertebrae of male Col1a2 +/ G610C and their wild-type controls ( Col1a2 +/+ ), were characterized to gain insight into the role of α2-chain collagen mutations in mineralization. Additionally, we examined the rescuability of the composition by sclerostin inhibition initiated by crossing Col1a2 +/ G610C with an LRP +/ A214V high bone mass allele. At age 10-days, vertebrae and tibia showed few alterations by micro-CT or Fourier transform infrared imaging (FTIRI). At 2-months-of-age, Col1a2 +/ G610C tibias had 13% fewer secondary trabeculae than Col1a2 +/+ , these were thinner (11%) and more widely spaced (20%) than those of Col1a2 +/+ mice. Vertebrae of Col1a2 +/ G610C mice at 2-months also had lower bone volume fraction (38%), trabecular number (13%), thickness (13%) and connectivity density (32%) compared to Col1 a2 +/+ . The cortical bone of Col1a2 +/ G610C tibias at 2-months had 3% higher tissue mineral density compared to Col1a2 +/+ ; Col1a2 +/ G610C vertebrae had lower cortical thickness (29%), bone area (37%) and polar moment of inertia (38%) relative to Col1a2 +/+ . FTIRI analysis, which provides information on bone chemical composition at ~ 7 μm-spatial resolution, showed tibias at 10-days did not differ between genotypes. Comparing identical bone types in Col1a2 +/ G610C to Col1a2 +/+ at 2-months-of-age, tibias showed higher mineral-to-matrix ratio in trabeculae (17%) and cortices (31%). and in vertebral cortices (28%). Collagen maturity was 42% higher at 10-days-of-age in Col1a2 +/ G610C vertebral trabeculae and in 2-month tibial cortices (12%), vertebral trabeculae (42%) and vertebral cortices (12%). Higher acid-phosphate substitution was noted in 10-day-old trabecular bone in vertebrae (31%) and in 2-month old trabecular bone in both tibia (31%) and vertebrae (4%). There was also a 16% lower carbonate-to-phosphate ratio in vertebral trabeculae and a correspondingly higher (22%) carbonate-to-phosphate ratio in 2 month-old vertebral cortices. At age 3-months-of-age, male femurs with both a Col1a2 +/ G610C allele and a Lrp5 high bone mass allele ( Lrp5 +/ A214V ) showed an improvement in bone composition, presenting higher trabecular carbonate-to-phosphate ratio (18%) and lower trabecular and cortical acid-phosphate substitutions (8% and 18%, respectively). Together, these results indicate that mutant collagen α2(I) chain affects both bone quantity and composition, and the usefulness of this model for studies of potential OI therapies such as anti-sclerostin treatments. [ABSTRACT FROM AUTHOR]

Abstract: Numerical simulations are performed to investigate the performance of an active magnetic regenerator (AMR) operating near room temperature. A two-dimensional porous model is established to analyze the impact different heat transfer fluids (HTFs) have on the performance of the AMR. The internal temperature distribution and cooling capacity of the system are analyzed and the influence of the HTF discussed. The simulation results show that when mercury is substituted in place of water as the HTF, the cooling capacity can be enhanced by nearly 600%. A fluid with high conductivity, high density, and low specific heat is most suitable for use as the HTF. Furthermore, as the environmental conditions have a great impact upon the performance of the AMR, three feasible methods of standardization testing are proposed. These involve: the evaluation index under fixed test environment conditions, a maximum exergy method, and a maximum specific exergy method around the Curie temperature. [Copyright &y& Elsevier]