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Introduction: The purpose of this study was to ascertain the primary ex vivo biomechanical stability of a novel bioabsorbable magnesium alloy (ZX00: Mg–Zn–Ca) bone anchor in human cadaveric proximal humeri, indicated in the reconstruction of the rotator cuff.

Methods: Twenty human Thiel-embalmed cadaveric humeri were prepared and freed from soft tissue. One $\varnothing$5.7 × 20.5-mm ZX00 anchor and one $\varnothing$5.5 mm × 16.3 mm Arthrex Titanium FT Corkscrew (ATC) control anchor were inserted into the footprint of the supraspinatus tendon, 15 mm apart. The humeri were mounted onto a material testing machine and following a 40 N preload, cyclic loading was performed over 400 cycles. If the construct remained intact, ultimate load to failure (ULTF) was measured using an increasing axial load of 1 mm/s, ULTF and mode of failure were recorded.

Results: No difference was found in the ability to withstand cyclic loading, mode or load-to-failure strengths between ZX00 and control anchors. The maximum tractional force loaded for the ZX00 anchors had a median of 257.4 N (range 165.3–328.2). The corresponding value for the ATC anchors averaged 239.9 N (range 118.9–306.7).

Conclusion: ZX00 alloy anchors appear to provide adequate initial biomechanical stability when compared to an industry-standard control in a cadaveric rotator cuff repair model.

Planar 1,2-naphthalocyanines present four different geometrical isomers of C_4h, C_2v, D_2h and C_s symmetries. In the case of magnesium complexes these four isomers have been isolated and characterized for the first time. The C_4h and C_s isomers of the magnesium complexes have been transformed in two steps into the corresponding lutetium mononaphthalocyanines 1,2-NcLuX.

Magnesium (Mg${}^{2+})$ is an essential mineral for several cellular functions. The concentration of this ion below the physiological concentration induces recurrent neuronal discharges both in slices of the hippocampus and in neuronal cultures. These epileptiform discharges are initially sensitive to the application of $N$-methyl-D-aspartate (NMDA) receptor antagonists, but these antagonists may lose their effectiveness with prolonged exposure to low [Mg${}^{2+}$], when extracellular Ca${}^{2+}$ reduction occurs, typical of ictal periods, indicating the absence of synaptic connections. The study herein presented aimed at investigating the effect of reducing the [Mg${}^{2+}$] during the induction of Nonsynaptic Epileptiform Activities (NSEA). As an experimental protocol, NSEA were induced in rat hippocampal dentate gyrus (DG), using a bath solution containing high-K${}^{+}$ and zero-added-Ca${}^{2+}$. Additionally, computer simulations were performed using a mathematical model that represents electrochemical characteristics of the tissue of the DG granular layer. The experimental results show that the reduction of [Mg${}^{2+}$] causes an increase in the duration of the ictal period and a reduction in the interictal period, intensifying epileptiform discharges. The computer simulations suggest that the reduction of the Mg${}^{2+}$ level intensifies the epileptiform discharges by a joint effect of reducing the surface charge screening and reducing the activity of the Na/K pump.

More than 4000 beard samples were collected from a single person every morning over a 12-year period and analyzed using a standard-free method. We detected significant annual variations in the concentrations of magnesium and calcium in the study period, although significant monthly and seasonal variations were not noted. Calcium tends not to be obtained from season-specific foods or drinks, so its variations may be affected by changes in the metabolism of the body. In contrast, however, potassium showed marked long-term variations with significant seasonal differences. As our previous studies confirmed that green vegetables contain large quantities of potassium and that their supply and consumption increase from May to July, the seasonal variations in potassium concentration were attributed to the ingestion of green vegetables. Although magnesium is also contained in green vegetables in large quantities, its principle supply sources are diverse and its concentration did not show any clear seasonal changes.

To evaluate a participatory role of environmental minerals in the pathogenesis of amyotrophic lateral sclerosis (ALS) in the Kii Peninsula of Japan, one of the three high-incidence foci, elemental and neuropathological investigations of lumbar spinal cord and hippocampal tissues were conducted, using particle-induced x-ray emission (PIXE) spectrometry and histomorphometric analysis. The PIXE analysis revealed extremely high contents of Al in both tissues of Kii ALS cases as compared with sporadic ALS and control cases. Morphometric analysis in the hippocampus showed abundant Alzheimer’s neurofibrillary tangles (NFTs) in the Kii ALS cases as compared with the other cases. Al content significantly correlated with the density of NFTs in all ALS cases (r=0.765, p < 0.0001). Interestingly, both Al content and density of NFTs in the hippocampus of all ALS cases significantly and negatively correlated with Ca and Mg contents in the birthplace area’s rivers. The extremely low Ca and Mg content in the focus rivers was confirmed along with the high ratio of Al₂O₃/CaO in the soil. Thus, Kii ALS patients may reflect the geochemical environment of their birthplace, i.e., long term Ca and Mg deficiencies and excess Al accumulation along with widespread NFT formation in the brain.

Bee venom (BV) has been used in Oriental medicine to treat inflammatory diseases, such as tendonitis, bursitis, and rheumatoid arthritis, despite the sensitivity of the victims and toxicity of the venom. This study examined the mechanisms for the effects of BV on the cardiovascular system in rats.

The arterial pressure and heart rate (HR) were measured in anesthetized rats. In addition, the left ventricular development pressure (LVDP) and total magnesium efflux ([Mg]_e) in isolated perfused hearts, the vascular tonic responses in the isolated aorta, and the blood ionic and biochemical changes were determined simultaneously. In the anesthetized rats, the mean arterial pressure, systolic pressure, and pulse pressure were reduced by BV in a dose-dependent manner, even though the HR was increased. BV had no effects on the relaxation of phenylephrine- or KCl-induced contraction of the aortic rings. In the isolated hearts, BV generated a reversible decrease in the LVDP and velocity with changes in pressure, which were accompanied by increases in the HR and [Mg]_e. BV increased the plasma ionized and total magnesium concentrations, and decreased the total magnesium level in the red blood cells. The ratio of ionized calcium/ionized magnesium was also decreased by the BV treatment. BV caused a detectable increase in blood creatine kinase, glutamic oxaloacetic transaminase, and lactic dehydrogenase, as well as a decrease in the blood total protein albumin and globulin levels.

These results suggest that BV induces cardiovascular depression by decreasing the cardiac pressure and increasing the ionized magnesium concentration in the blood.

The electrochemical deposition of magnesium was investigated in ethereal Grignard salt solution with tetraethylammonium bistrifluoro-methanesulfonimidate additive, using cyclic voltammetry, potentiostatic transients, and scanning electron microscope measurements. The voltammograms showed the presence of reduction and oxidation peaks associated with the deposition and dissolution of magnesium. From the analysis of the experimental current transients, it was shown that the magnesium deposition process was characterized as a three-dimensional nucleation. The deposited product obtained from potentiostatic reduction presented a generally uniform and dense film.

An inverse template method that relies on the use of a controlled porous spacer material was implemented to produce periodic magnesium (Mg) foams. Bulk infiltration pressures were varied to determine a processing-property map. The microstructure and mechanical properties of the resulting periodic Mg foams were investigated using optical and scanning electron microscopy (SEM), and compression testing, respectively. SEM was also used to analyze the surface topology of the periodic foams and compare it to the original template material. It was found that the casting pressure has a great effect not only on the success of the infiltration but also the surface roughness and other microstructural features of the foam.

In this study, three types of functionally graded Al₁₈B₄O₃₃/Mg composites which consisted of 2, 3 and 4 layers and where volume fractions of Al₁₈B₄O₃₃ were gradually changing from 0 to 35% were fabricated using squeeze infiltration technique. The mechanical parameters of each layer were measured for the analysis of residual stress. Elastic finite element numerical models were applied to the analysis of thermal residual stress. The analytic results showed that the residual stresses were significantly decreased in the macrointerface with increasing the number of layer.

Magnesium is light, biocompatible and has similar mechanical properties to natural bone, so it has the potential to be used as a biodegradable material for orthopedic applications. However, pure magnesium severely corrodes in a physiological environment, which may hinder its use for in vivo applications. Protective coatings are effective method to delay the corrosion of Mg. In this study, sol-gel and hydroxyapatite (HA) coatings were applied onto the surface of pure magnesium substrates using a biomimetic technique. The corrosion rate of surface-treated substrates was tested. It was found that both types of coatings substantially slowed down the corrosion of the substrate, the 60Ca so-gel and HA coating was more effectively than the 100Si so-gel and HA coating in hindering the degradation of the substrate. Thus, the corrosion rate of magnesium implants can be closely tailored by coating sol-gel then coating apatite thereby monitoring the release of magnesium ions into the body.

Magnesium (Mg) crystal structures are extensively explored using an evolutionary algorithm implemented in the USPEX code. Two structures with simple trigonal and tetragonal symmetries are discovered to possibly exist under high pressure. The stability of these symmetries is determined by elastic constants and phonon spectrum calculations. First-principle calculations are performed to investigate the structural, mechanical and electronic properties of different Mg structures under high pressure (up to 300 GPa). Above 190 GPa, the trigonal structure is more stable than the hexagonal close-packed (HCP) structure. Particularly, the trigonal structure can be considered a compromise between face-centered cubic (FCC) and HCP blocks. Interestingly, the tetragonal structure density is only 95% HCP structure. In addition, the tetragonal structure has strong directional bonding but is less stable than the HCP structure (up to 600 GPa). Pressure significantly changes the electronic properties of both structures although they remain metallic up to 300 GPa.

In this paper, hierarchical surface structures were developed to achieve the superhydrophobicity on AZ31 magnesium alloys. The uniform nodular microstructure was constructed by laser processing, and the subsequent cobalt electrodeposition fabricated a nanostructured needle-like morphology onto the surface nodules. The superhydrophobic surfaces prepared under varied electrodeposition current densities were characterized. When applying 7 mA/cm² current density, the sample revealed the best superhydrophobic performance. The chemical stability of superhydrophobic samples was tested, which confirmed excellent superhydrophobicity was hardly affected by the corrosion environment. The results showed the samples still possessed the hydrophobic ability after tests. The developed fabrication method combines the advantages of laser processing and electrodeposition, which serves as a fast and cost-effective pathway to manufacture superhydrophobic surfaces.

Polycrystalline nickel–zinc ferrites of chemical formula Ni_0.65-xMg_xZn_0.35Fe₂O₄ (x = 0.00 to 0.2 in steps of 0.04) have been prepared by conventional ceramic technique. Calcination and sintering of all samples have been carried out in air atmosphere at 950°C and 1250°C, respectively, followed by natural cooling to room temperature. All the samples were characterized by the X-ray diffraction (XRD) for structure determination. These samples were then investigated for their magnetic and electric properties, including saturation magnetization, Curie temperature, initial permeability measurements and DC electrical resistivity. Porosity was decreased drastically from 15% to 5% showed better quality of the sintered samples. There were increments in initial permeability and DC electrical resistivity throughout the series of samples. Variations in the observed properties as a function of magnesium concentration have been discussed in light of the existing understanding.

The isotope shifts of the $2s{}^2{\mathrm{\text{S}}}_{1/2}$–$2p{}^2{\mathrm{\text{P}}}_J(J=1/2,3/2)$ transitions for the Li-like neutron-rich and neutron-deficient ${}^{21\text{–}32}\mathrm{\text{Mg}}$ isotopes are calculated using the multi-configuration Dirac–Hartree–Fock (MCDHF) method and the relativistic configuration interaction approach. The results provided herein can be employed for the consistency check with the nuclear root-mean-square (rms) nuclear charge radii of the short-lived magnesium isotopes from the experimental isotope shifts using the corresponding transitions. The methods used here could also be applied to other few-electron Li-like systems and the analogous isotope shift results could be obtained.

This work focuses on the analytical study of mechanical and thermal properties of a nanocomposite that can be obtained by reinforcing graphene in magnesium. The estimated mechanical and thermal properties of graphene–magnesium nanocomposite are much higher than magnesium and other existing alloys used in aerospace materials. We also altered the weight percentage of graphene in the composite and observed mechanical and thermal properties of the composite increase with increase in concentration of graphene reinforcement. The Young’s modulus and thermal conductivity of graphene–magnesium nanocomposite are found to be $\ge$165 GPa and $\ge$175 W/mK, respectively. Nanocomposite material with desired properties for targeted applications can also be designed by our analytical modeling technique. This graphene–magnesium nanocomposite can be used for designing improved aerospace structure systems with enhanced properties.

In this paper, kappa and Druyvesteyn distributions of electronic velocity are discussed for non-Maxwellian distribution. For accurate temperature and electron density diagnostics of Magnesium plasma, for the Magnesium VIII ${}^2{P}_{1/2}^0$ to ${}^2{P}_{3/2}^0$ transitions, we calculate kappa averaged collision strengths for $\kappa$ = 2, 3 and 5 and the Druyvesteyn averaged collision strengths for $x$ = 1.5, 2 and 3, for temperature between $5\times 10^4$ and $2.5\times 10^5\mathrm{\text{K}}$. Results indicate that the kappa averaged collision strengths are slightly larger than those for the Maxwellian distribution, and the Druyvesteyn averaged collision strengths are slightly smaller than those for the Maxwellian distribution, furthermore, the averaged collision strengths will be close to those for Maxwellian distribution with increasing $\kappa$ for the kappa distribution and with decreasing $x$ for the Druyvesteyn distribution. The excitation rate coefficients are also calculated for Maxwellian and non-Maxwellian distributions. This discussion will be significant in study of plasma for the non-Maxwellian distribution.

Modification of bioceramics by ion implantation of magnesium (Mg) is of interest as Mg is the fourth abundant cation in the human body. In this work, magnesium was ion-implanted into a ZrO₂ based bioceramic stabilized with Y₂O₃ and Al₂O₃. Both Mg-implanted and unimplanted samples were soaked in a simulated body fluid (SBF) for a period of time. The deposits on the surface of various samples were characterized with scanning electron microscope (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). We find that the Mg-implanted ZrO₂ shows better bioactivity than the plain bioceramic. These results indicate that Mg-implantation can improve the bioactivity of the ZrO₂ based bioceramic. Mechanisms governing the improvement are discussed in this paper.

AZ91D magnesium alloys with and without dispersed SiC particles were oxidized between 420 and 500°C in air. They oxidized to fine MgO oxide grains containing dissolved ions of Al. Their oxidation rates increased almost linearly, with an increase in the oxidation temperature and time. SiC particles did not oxidize during oxidation, and increased the oxidation resistance of the alloy through diminishing the exposed surface area. With the increase in the amount of the dispersed SiC particles from 5 to 10, and to 20 wt.%, the oxidation resistance progressively increased.

The need of engineered materials with high strength to weight ratio was instrumental for the development of a novel magnesium metal–metal composite with the addition of titanium (reinforcement) and aluminum (alloying element) through disintegrated melt deposition technique. The X-ray diffraction analysis and scanning electron microscopy analysis used to explore the metallurgical insights of the developed magnesium metal–metal composite. Wear tests were carried out with pin-on-disc equipment by varying the input parameters load and sliding velocity over a sliding distance of 2000m. Wear was obtained as the output from the experiments, and the same was analyzed through Pareto analysis of variance, to identify the significant parameters. Also, a fuzzy logic-based model was developed to predict the wear behavior of the metal–metal composite. The wear mechanisms involved in the dry sliding wear behavior were analyzed through worn surface analysis and wear debris analysis.

Magnesium is reinforced with three different weight percentages (5%, 10% and 15%) of SiC particles (200 mesh size) by stir casting technique to fabricate Mg/SiC_p composites. The Scanning Electron Microscope (SEM) images, micro and macro hardness of three different composites are investigated. The comparison of micro and macro hardness clearly shows that increase in the weight percentage of SiC contributed to increase in hardness. However, uniform dispersion of SiC can be achieved while adding 5% SiC in the composite. Then, the Box Behnken experimental design in response surface methodology is employed for machining 3mm diameter hole in the Mg/SiC_p samples using EDM. The second-order model for Material Removal Rate (MRR) and Tool Wear Rate (TWR) are developed with the influencing parameters of weight percentage of SiC, current, pulse on time and pulse off time. The parameter optimization yields maximum MRR and minimum TWR.