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Additive manufacturing (AM) technologies allow for the creation of components with greater design flexibility. The complexity in geometry and composition can enhance functionality, while parts made from multiple materials have the capacity to deliver improved performance. Nonetheless, most multimaterial printing methods are still in their infancy and face numerous challenges. Numerous materials require individual post-treatment, and some may not be compatible with each other regarding shrinkage, melting or sintering temperatures, and interactions. In this study, we introduce a technique for producing a metal–ceramic multimaterial prototype for electronic packages through powder-bed additive manufacturing technology. Silicon carbide-based ceramic substrate was manufactured by selective laser melting, on which molybdenum-based conductive tracks were printed. The results indicated that the SiC-based samples exhibit a relatively uniform microstructure with homogeneously distributed porosity. Mo-based powder containing 5% silicon was successfully SLM-ed on the SiC layer. The microstructural and chemical analyses show that Mo reacted with Si during selective laser melting, resulting in formation of molybdenum silicides. The surface of Mo-based layer surface is smooth; however, there are few cracks on it. The Vickers hardness was measured to be 7.6 ± 1 GPa. The electrical resistivity of the conductive track is 2.8 × 10−5 Ω·m.

Electroactive polymers are effective actuators that respond to electrical stimuli, producing mechanical displacement. Their combined features encourage the application of electroactive polymers in the medical and healthcare sectors. Dielectric elastomers (DEAs) are the most promising electroactive polymers due to their high efficiency, fast response time, lightweight, and large strain. This review discusses the working principle, typical configurations, structures, key materials for DEAs, and their potential use in biological systems. Additionally, we discuss the applications, advantages, and disadvantages of DEAs in modern medicine. The influence of dielectric permittivity and the elastic modulus of the material on the deformation rate of the elastomer is discussed. Mechanical, biological, and chemical requirements for biomedical DEAs are addressed. The role of the structure of a dielectric elastomer actuator in the development of artificial muscles and other actuators is considered.

New technologies in additive manufacturing and patient-specific CT-based custom implant designs make it possible for previously unimaginable salvage and limb-sparing operations a practical reality. This study presents the design and fabrication of a lattice-structured implant for talus replacement surgery. Our primary case involved a young adult patient who had sustained severe damage to the talus, resulting in avascular necrosis and subsequent bone collapse. This condition caused persistent and debilitating pain, leading the medical team to consider amputation of the left foot at the ankle level as a last resort. Instead, we proposed a Ti6Al4V-based patient-specific implant with lattice structure specifically designed for pan-talar fusion. Finite element simulation is conducted to estimate its performance. To ensure its mechanical integrity, uniaxial compression experiments were conducted. The implant was produced using selective laser melting technology, which allowed for precise and accurate construction of the unique lattice structure. The patient underwent regular monitoring for a period of 24 months. At 2-years follow-up the patient successfully returned to activities without complication. The patient’s functional status was improved, limb shortening was minimized.

Copper oxide-doped alumina nanofibres were fabricated by the solution combustion method. The bundled alumina nanofibres were impregnated with a copper nitrate–glycine (oxidizer–fuel) solution and heat-treated in an open-air environment at 400 °C for 30 min. The microstructure and phase composition of the final product were characterized by XRD, SEM, and EDS analyses. A uniform distribution of a fine-grained CuO film on the surface of gamma-alumina nanofibres was revealed. The obtained results showed a dramatical effect of the amount of fuel, the ratios of fuel to oxidizer and fibres to Cu(II) ions in the reaction mixture on the particle size of the combustion product, its phase composition, and microstructure morphology.

Copper oxide-doped alumina nanofibres were fabricated by the solution combustion method. The bundled alumina nanofibres were impregnated with a copper nitrate-glycine (oxidizer-fuel) solution and heat-treated in an open-air environment at 400 degree C for 30 min. The microstructure and phase composition of the final product were characterized by XRD, SEM, and EDS analyses. A uniform distribution of a fine-grained CuO film on the surface of gamma-alumina nanofibres was revealed. The obtained results showed a dramatical effect of the amount of fuel, the ratios of fuel to oxidizer and fibres to Cu(II) ions in the reaction mixture on the particle size of the combustion product, its phase composition, and microstructure morphology.

Nickel aluminate spinel (NiAl2O4) has received attention as a catalyst solid support due to its stability, strong resistance to acids and alkalis and high melting point. The properties and quality of the catalysts are heavily affected by crystal size, morphology, phase homogeneity and surface characteristics of the materials, which themselves are dependent on method and parameters of processing rout. In this work, we report on the fabrication of novel NiAl2O4 nanofibers covered by NiO nanolayer by combustion method.The XRD patterns show that the combustion technique was excellent to prepare NiO/NiAl2O4 nanofibers. The crystallite sizes of NiAl2O4 and NiO were found to be around 27 and 19 nm correspondingly. Scanning electron micrographs (SEM) and Energy dispersive X-ray (EDX) analysis showed that the NiO/NiAl2O4 nanofibers with more than 20 nm in diameter were consist of NiAl2O4 core and NiO outer layer.

Nickel aluminate spinel (NiAl2O4) has received attention as a catalyst solid support due to its stability, strong resistance to acids and alkalis and high melting point. The properties and quality of the catalysts are heavily affected by crystal size, morphology, phase homogeneity and surface characteristics of the materials, which themselves are dependent on method and parameters of processing rout. In this work, we report on the fabrication of novel NiAl2O4 nanofibers covered by NiO nanolayer by combustion method.The XRD patterns show that the combustion technique was excellent to prepare NiO/NiAl2O4 nanofibers. The crystallite sizes of NiAl2O4 and NiO were found to be around 27 and 19 nm correspondingly. Scanning electron micrographs (SEM) and Energy dispersive X-ray (EDX) analysis showed that the NiO/NiAl2O4 nanofibers with more than 20 nm in diameter were consist of NiAl2O4 core and NiO outer layer.

Ceramic materials have become of high industrial importance in some applications as their properties outperform ones of metallic components. However, use of ceramics is limited due to the difficulties in shaping. Electrically conductive ceramics can be machined by Electro-Discharge Machining (EDM) irrespective of its hardness or strength. In this study, yttria stabilized zirconia (YTZP) conductive composite was produced by incorporation of the cost-effective graphene coated alumina nanofibers (ANFC) into the matrix. Almost fully dense YTZP/5 vol.% ANFC nanocomposite was obtained by spark plasma sintering (SPS) at 1250 °C with uniaxial pressure of 40 MPa. Scanning electron microscopy observation of the microstructures showed that ANFCs were homogeneously dispersed in the matrix. Addition of ANFC resulted in slightly decreased mechanical properties, but the electrical resistivity of the composite dropped 9 orders of magnitude compared to monolithic zirconia, exhibiting 1.4 Ω∙m, satisfying the required condition for the EDM.

Graphene is a promising component for next-generation high-performance structural and multifunctional composite materials. Graphene deposited onto nanofibers of high aspect ratio can serve as reinforcement agent for improving ceramic fracture toughness and electroconductivity. It was found that quality and quantity of graphene sheets on the fiber surface essentially depends on the pyrolysis of carbon source conditions such as gas flow, duration, temperature and the composition of the gas mixture. The alumina/graphene composites of 10 and 15 wt% of nanofibers covered by graphene were produced by spark plasma sintering (SPS) at 1380 °C. Both composites show improvement in mechanical and electrical properties as compared to the monolithic alumina. The main advantage of the graphene growth on the fibers surface is a lack of complicated step of constituents mixing. Graphene platelets are believed to act as toughening agents prevailing crack propagation under loading.

Assessments of age-specific mortality and life expectancy have been done by the UN Population Division, Department of Economics and Social Affairs (UNPOP), the United States Census Bureau, WHO, and as part of previous iterations of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD). Previous iterations of the GBD used population estimates from UNPOP, which were not derived in a way that was internally consistent with the estimates of the numbers of deaths in the GBD. The present iteration of the GBD, GBD 2017, improves on previous assessments and provides timely estimates of the mortality experience of populations globally. The GBD uses all available data to produce estimates of mortality rates between 1950 and 2017 for 23 age groups, both sexes, and 918 locations, including 195 countries and territories and subnational locations for 16 countries. Data used include vital registration systems, sample registration systems, household surveys (complete birth histories, summary birth histories, sibling histories), censuses (summary birth histories, household deaths), and Demographic Surveillance Sites. In total, this analysis used 8259 data sources. Estimates of the probability of death between birth and the age of 5 years and between ages 15 and 60 years are generated and then input into a model life table system to produce complete life tables for all locations and years. Fatal discontinuities and mortality due to HIV/AIDS are analysed separately and then incorporated into the estimation. We analyse the relationship between age-specific mortality and development status using the Socio-demographic Index, a composite measure based on fertility under the age of 25 years, education, and income. There are four main methodological improvements in GBD 2017 compared with GBD 2016: 622 additional data sources have been incorporated; new estimates of population, generated by the GBD study, are used; statistical methods used in different components of the analysis have been further standardised and improved; and the analysis has been extended backwards in time by two decades to start in 1950. Globally, 18·7% (95% uncertainty interval 18·4–19·0) of deaths were registered in 1950 and that proportion has been steadily increasing since, with 58·8% (58·2–59·3) of all deaths being registered in 2015. At the global level, between 1950 and 2017, life expectancy increased from 48·1 years (46·5–49·6) to 70·5 years (70·1–70·8) for men and from 52·9 years (51·7–54·0) to 75·6 years (75·3–75·9) for women. Despite this overall progress, there remains substantial variation in life expectancy at birth in 2017, which ranges from 49·1 years (46·5–51·7) for men in the Central African Republic to 87·6 years (86·9–88·1) among women in Singapore. The greatest progress across age groups was for children younger than 5 years; under-5 mortality dropped from 216·0 deaths (196·3–238·1) per 1000 livebirths in 1950 to 38·9 deaths (35·6–42·83) per 1000 livebirths in 2017, with huge reductions across countries. Nevertheless, there were still 5·4 million (5·2–5·6) deaths among children younger than 5 years in the world in 2017. Progress has been less pronounced and more variable for adults, especially for adult males, who had stagnant or increasing mortality rates in several countries. The gap between male and female life expectancy between 1950 and 2017, while relatively stable at the global level, shows distinctive patterns across super-regions and has consistently been the largest in central Europe, eastern Europe, and central Asia, and smallest in south Asia. Performance was also variable across countries and time in observed mortality rates compared with those expected on the basis of development. This analysis of age-sex-specific mortality shows that there are remarkably complex patterns in population mortality across countries. The findings of this study highlight global successes, such as the large decline in under-5 mortality, which reflects significant local, national, and global commitment and investment over several decades. However, they also bring attention to mortality patterns that are a cause for concern, particularly among adult men and, to a lesser extent, women, whose mortality rates have stagnated in many countries over the time period of this study, and in some cases are increasing. Bill & Melinda Gates Foundation.