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Mg-3Zn/HA Biodegradable Composites Synthesized via Spark Plasma Sintering for Temporary Orthopedic Implants
In the present study, an attempt has been made to improve the mechanical properties, biocompatibility and degradation rate of Mg/3Zn matrix composite, by reinforcing with chemically inert and osteoconductive hydroxyapatite (HA). The composites were synthesized through spark plasma sintering for better consolidation. The HA content, in Mg/3Zn matrix, was optimized with an aim of improving mechanical behavior, corrosion resistance and biocompatibility simultaneously. It has been observed that reinforcement with 15 wt.% HA could slow down the corrosion rate by ~ 60% and improve the hardness and compression strength by ~ 42.8 and 18%, respectively. In vitro studies, up to 56 days, unveil the effect of HA reinforcement in corrosion resistance of magnesium-based matrix. Osteoblastic activity has shown better cell proliferation on the composite surfaces, which were reinforced with HA.
Attenuation correction and metal artifact reduction in FDG PET/CT for prosthetic heart valve and cardiac implantable device endocarditis
No abstract prepared.
Iodine-123-metaiodobenzylguanidine cardiac SPECT imaging in the qualification of heart failure patients for ICD implantation
No abstract prepared.
Hybrid Cathode Lithium Battery Discharge Simulation for Implantable Cardioverter Defibrillators Using a Coupled Electro-Thermal Dynamic Model
Not provided.
Characterisation of radiation damage in W and W-based alloys from 2MeV self-ion near-bulk implantations
The displacement damage induced in bulk W and W-5 wt.% Re and W-5 wt.% Ta alloys by 2 MeV W + irradiation to doses 3.3×10 17 - 2.5×10 19 W + /m 2 at temperatures ranging from 300 to750°C has been characterized by transmission electron microscopy. An automated sizing and counting approach based on Image J has been proposed and performed for all irradiation data. In all cases the damage comprised dislocation loops, mostly of interstitial type, with Burgers vectors b = ½<111> (> 60%) and b = <100>. The diameters of loops did not exceed 20 nm, with the majority being ≤ 6 nm. The loop number density varied between 10 22 and 10 23 loops/m 3 . With increasing irradiation temperature, the loop size distributions shifted towards larger sizes, and there was a substantial decrease in loop number densities. The damage microstructure was less sensitive to dose than to temperature. Under the same irradiation conditions, loop number densities in the alloys were higher than in pure W but loops were smaller. In grains with normals close to z = <001>, loop strings developed in W at temperatures ≥ 500°C and doses ≥ 1.2 dpa, but such strings were not observed in the W-Re or W-Ta alloys. However, in other grain orientations complex structures appeared in all materials and dense dislocation networks formed at higher doses.
In situ micro tensile testing of He+2 ion irradiated and implanted single crystal nickel film
Not Available
Implantable biomaterial based on click chemistry for targeting small molecules
Not Available
3D-ink-extruded titanium scaffolds with porous struts and bioactive supramolecular polymers for orthopedic implants
Not Available
Changes in local surface structure and Sr depletion in Fe-implanted SrTiO[subscript 3] (001)
Abstract not provided
Magnesium and fluoride doped hydroxyapatite coatings grown by pulsed laser deposition for promoting titanium implant cytocompatibility
Not Available
Near-infrared laser irradiation improves the development of mouse pre-implantation embryos
The aim of the present study was to assess the effects of near-infrared laser irradiation on the in vitro development of mouse embryos. Female ICR mice were superovulated with pregnant mare serum gonadotropin and human chorionic gonadotropin (hCG), and mated with male mice. Two-cell stage embryos were collected 40 h after administering hCG and cultured in M16 medium. Two-cell embryos (0 h after culture), 8-cell embryos (approx. 30 h after culture), morula (approx. 48 h after culture), and blastocysts (approx. 73 h after culture) were irradiated at 904 nm for 60 s. These embryos were cultured in a time-lapse monitoring system and the timing of blastocyst hatching was evaluated. Some of the irradiated blastocysts were transferred to the uterine horns of pseudopregnant recipients immediately after irradiation. Pregnancy rates, and offspring growth and fertility, were evaluated. Near-infrared laser irradiation increased the speed of in vitro mouse embryo development. In irradiated blastocysts, hatching was faster than in control (non-irradiated) blastocysts (18.4 vs. 28.2 h, P < 0.05). When 195 irradiated blastocysts were transferred to 18 pseudopregnant mice, all became pregnant and 92 (47.2%) normal-looking pups were born alive. When 182 control blastocysts were transferred to 17 pseudopregnant mice, 14 (82.4%) became pregnant and 54 (29.7%) normal-looking pups were born alive. The growth trajectories (up to 5 weeks) of offspring from irradiated blastocysts were similar to those from control blastocysts. Second generation offspring from transplanted animals were all fertile. These results indicate that near-infrared laser irradiation improves the quality of mouse embryo development in vitro, and increases the live birth rate without affecting the normality of the offspring. Thus, the near-infrared laser method may enhance the quality of embryos and contribute to improvements in reproductive technologies in mammals. - Highlights: • Irradiation of blastocysts with a near-infrared laser improves embryo development. • Irradiation of blastocysts increases the live birth rate after embryo transfer. • Irradiation of blastocysts did not affect the normality of the pups. • Near-infrared laser irradiation may be useful to enhance the quality of embryos. • This study may contribute to improvements in reproductive technologies in mammals.