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Materials (Basel, Switzerland) May 2024In the present paper, composite thin films of barium strontium titanate (BaSrTiO) with an acceptor modifier (magnesium oxide-MgO) were deposited on metal substrates...
In the present paper, composite thin films of barium strontium titanate (BaSrTiO) with an acceptor modifier (magnesium oxide-MgO) were deposited on metal substrates (stainless steel type) using the sol-gel method. The composite thin films feature BaSrTiO ferroelectric solid solution as the matrix and MgO linear dielectric as the reinforcement, with MgO concentrations ranging from 1 to 5 mol%. Following thermal treatment at 650 °C, the films were analyzed for their impedance response. Experimental impedance spectra were modeled using the Kohlrausch-Williams-Watts function, revealing stretching parameters (β) in the range of approximately 0.78 to 0.89 and 0.56 to 0.90 for impedance and electric modulus formalisms, respectively. Notably, films modified with 3 mol% MgO exhibited the least stretched relaxation function. Employing the electric equivalent circuit method for data analysis, the "circle fit" analysis demonstrated an increase in capacitance from 2.97 × 10 F to 5.78 × 10 F with the incorporation of 3 mol% MgO into BST-based thin films. Further analysis based on Voigt, Maxwell, and ladder circuits revealed trends in resistance and capacitance components with varying MgO contents, suggesting non-Debye-type relaxation phenomena across all tested samples.
PubMed: 38893755
DOI: 10.3390/ma17112491 -
ACS Omega Jun 2024[This corrects the article DOI: 10.1021/acsomega.2c01450.].
[This corrects the article DOI: 10.1021/acsomega.2c01450.].
PubMed: 38882120
DOI: 10.1021/acsomega.4c04613 -
Materials Today. Bio Jun 2024Osteoporosis (OP) can result in slower bone regeneration than the normal condition due to the imbalance between osteogenesis and osteoclastogenesis, making osteoporotic...
Injectable and high-strength PLGA/CPC loaded ALN/MgO bone cement for bone regeneration by facilitating osteogenesis and inhibiting osteoclastogenesis in osteoporotic bone defects.
Osteoporosis (OP) can result in slower bone regeneration than the normal condition due to the imbalance between osteogenesis and osteoclastogenesis, making osteoporotic bone defects healing a significant clinical challenge. Calcium phosphate cement (CPC) is a promising bone substitute material due to its good osteoinductive activity, however, the drawbacks such as fragility, slow degradation rate and incapability to control bone loss restrict its application in osteoporotic bone defects treatment. Currently, we developed the PLGA electrospun nanofiber sheets to carry alendronate (ALN) and magnesium oxide nanoparticle (nMgO) into CPC, therefore, to obtain a high-strength bone cement (C/AM-PL/C). The C/AM-PL/C bone cement had high mechanical strength, anti-washout ability, good injection performance and drug sustained release capacity. More importantly, the C/AM-PL/C cement promoted the osteogenic differentiation of bone marrow mesenchymal stem cells and neovascularization via the release of Mg (from nMgO) and Ca (during the degradation of CPC), and inhibited osteoclastogenesis via the release of ALN . Moreover, the injection of C/AM-PL/C cement significantly improved bone healing in an OP model with femur condyle defects . Altogether, the injectable C/AM-PL/C cement could facilitate osteoporotic bone regeneration, demonstrating its capacity as a promising candidate for treatment of osteoporotic bone defects.
PubMed: 38873105
DOI: 10.1016/j.mtbio.2024.101092 -
Science Advances Jun 2024Magnesium oxide (MgO) is a major component of the Earth's mantle and is expected to play a similar role in the mantles of large rocky exoplanets. At extreme pressures,...
Magnesium oxide (MgO) is a major component of the Earth's mantle and is expected to play a similar role in the mantles of large rocky exoplanets. At extreme pressures, MgO transitions from the NaCl 1 crystal structure to a CsCl 2 structure, which may have implications for exoplanetary deep mantle dynamics. In this study, we constrain the phase diagram of MgO with laser-compression along the shock Hugoniot, with simultaneous measurements of crystal structure, density, pressure, and temperature. We identify the 1 to 2 phase transition between 397 and 425 gigapascal (around 9700 kelvin), in agreement with recent theory that accounts for phonon anharmonicity. From 425 to 493 gigapascal, we observe a mixed-phase region of B1 and B2 coexistence. The transformation follows the Watanabe-Tokonami-Morimoto mechanism. Our data are consistent with 2-liquid coexistence above 500 gigapascal and complete melting at 634 gigapascal. This study bridges the gap between previous theoretical and experimental studies, providing insights into the timescale of this phase transition.
PubMed: 38848357
DOI: 10.1126/sciadv.adk0306 -
Ecotoxicology and Environmental Safety Jul 2024This study aimed to evaluate the effect of adding liquid extract of algae (Hypnea musciformis, Grateloupia acuminata, and Sargassum muticum) (HGS) and Magnesium oxide...
Synergistic effect of green synthesis magnesium oxide nanoparticles and seaweed extract on improving water quality, health benefits, and disease resistance in Nile tilapia.
This study aimed to evaluate the effect of adding liquid extract of algae (Hypnea musciformis, Grateloupia acuminata, and Sargassum muticum) (HGS) and Magnesium oxide nanoparticles (MgO NPs) using this extract to rear water of Oreochromis niloticus, on improving culture water indices, growth performance, digestive enzyme, hemato-biochemical characters, immune, antioxidative responses, and resistance after challenged by Aeromonas hydrophila with specific refer to the potential role of the mixture in vitro as resistance against three strains bacteria (Aeromonas sobria, Pseudomonas fluorescens, P. aeruginosa) and one parasite (Cichlidogyrus tilapia). The first group represented control, HGS0, whereas the other group, HGS5, HGS10, and HGS15 mL of liquid extract, as well as all groups with 7.5 μg mL MgO-NPs added to culture water of O. niloticus, for 60 days. Data showed that increasing levels at HGS 10 and HGS15 mL in to-culture water significantly enhanced growth-stimulating digestive enzyme activity and a significantly improved survival rate of O. niloticus after being challenged with A. hydrophila than in the control group. The total viability, coliform, fecal coliform count, and heavy metal in muscle partially decreased at HGS 10 and HGS15 mL than in the control group. Correspondingly, the highest positive effect on hemato-biochemical indices was noticed at levels HGS 10 and HGS15 mL. Fish noticed an improvement in immune and antioxidant indices compared to control groups partially at HGS 10 and HGS15 mL. Interestingly, fish cultured in rearing water with the mixture provided downregulated the related inflammatory genes (HSP70, TNF, IL-1β, and IL-8) partially at HGS15 mL. In vitro, the mixture showed positive efficiency as an antibacterial and partially antiparasitic at HGS 10 and HGS15 mL. This study proposes utilizing a mixture of (HGS) and (MgO-NPs) with optimum levels of 10-15 mL in cultured water to improve water indices, growth, health status, and increased resistance of O. niloticus against bacterial and parasitic infection.
Topics: Animals; Magnesium Oxide; Cichlids; Disease Resistance; Water Quality; Seaweed; Fish Diseases; Plant Extracts; Nanoparticles; Green Chemistry Technology; Metal Nanoparticles; Aeromonas hydrophila; Sargassum
PubMed: 38843743
DOI: 10.1016/j.ecoenv.2024.116522 -
Cureus Apr 2024Self-treatment with vitamin, mineral, and herbal supplements has become increasingly common among patients for the treatment of psychiatric disorders. Magnesium, in... (Review)
Review
Self-treatment with vitamin, mineral, and herbal supplements has become increasingly common among patients for the treatment of psychiatric disorders. Magnesium, in particular, is popular on social media for the treatment of anxiety and insomnia. Meanwhile, preclinical studies support associations between magnesium status, sleep quality, and symptoms of anxiety. The extent to which these claims are evidence-based is unclear. Therefore, a systematic review was performed to provide an updated examination of the clinical evidence on the use of magnesium for the treatment of the above conditions given the popularity of such supplements among patients and the public at large. A thorough search of the PubMed database was performed and results were systematically reviewed using PRISMA guidelines. The search was limited to anxiety disorders and sleep disorders and included interventional trials only. Exclusion criteria included insufficient (<50 mg/12.5% of recommended daily allowance (RDA)) or unknown magnesium dose, >3 other potentially active compounds present in the formulation, and articles in languages other than English. This query returned 860 articles of which 15 met full inclusion criteria. Eight measured sleep-related outcomes, seven measured anxiety-related outcomes, and one examined both. Sleep quality was measured most frequently using the Pittsburg Sleep Quality Index (PSQI). Anxiety measures included self-reported measures such as the Hamilton Anxiety Scale. The majority of included studies demonstrated improvement in at least one sleep- or anxiety-related parameter. Five out of eight sleep-related studies reported improvements in sleep parameters, while two studies reported no improvements, and one reported mixed results. Five out of seven studies measuring anxiety-related outcomes reported improvements in self-reported anxiety. Firm conclusions were limited by the heterogeneity of the data and the small number of participants involved in most of the studies. The dosages, formulations, and durations of the magnesium interventions used also differed across studies. Furthermore, some studies included additional, potentially active ingredients, further complicating interpretations. Given the generally positive results across studies, the preponderance of preclinical evidence, and minimal side effects, however, supplemental magnesium is likely useful in the treatment of mild anxiety and insomnia, particularly in those with low magnesium status at baseline. Notably, both negative anxiety trials featured populations with underlying endocrine factors likely contributing to their symptoms (patients with premenstrual symptoms and post-partum women). Nonetheless, larger, randomized clinical trials are needed to confirm efficacy and to establish the most effective forms and dosages of magnesium for the treatment of insomnia and anxiety disorders.
PubMed: 38817505
DOI: 10.7759/cureus.59317 -
Scientific Reports May 2024One of the major problems of using nanofluids in heat exchange applications is the forming and deposition of nanoparticles on the inner surface of the heat exchanger. In...
One of the major problems of using nanofluids in heat exchange applications is the forming and deposition of nanoparticles on the inner surface of the heat exchanger. In this paper, Water-Cmc fluid is used as a surfactant for nanoparticles to prevent deposition and congregation. The pressure drops and heat transfer in U-bend double pipe heat exchanger based on water-MgO-Cmc fluid, are examined. Nanoparticles of Magnesium Oxide (MgO) and Carboxymethyl Cellulose (Cmc) are used with pure water as a base fluid. The experimental rig and procedures are designed to facilitate various operational conditions such as flow rate, volume concentration of MgO particles and weight concentration of Cmc particles. Furthermore, convective heat transfer coefficient, heat exchanger effectiveness, pressure drop, friction factor, under different conditions, are measured. The results demonstrate convective heat transfer coefficient of U-bend double pipe heat exchangers is enhanced by 35% for 1 MgO vol.% and 0.2 Cmc wt.% compared to base fluid (Water-Cmc). It is concluded that pressure drops are directly proportion to the increase of MgO nanoparticles at same Cmc concentration by 23% at 0.2 wt.%. Whilst, friction factor of the system is inversely proportion to the increase of volumetric flow rate of water-MgO-Cmc fluid. An increase in MgO nanoparticle concentration increases the friction factor, hence maximum friction factor enhancement by 38% for MgO concentration of 1 vol.%. The effectiveness of heat exchanger is slightly increased by 8% with increase of MgO concentration and flow rate. Finally, thermo-physical characteristics of water-MgO-Cmc fluid at various temperatures, are measured.
PubMed: 38816432
DOI: 10.1038/s41598-024-63043-6 -
Nano Letters Jun 2024Magnesium is a recent addition to the plasmonic toolbox: nanomaterials that efficiently utilize photons' energy due to their ability to sustain localized surface plasmon...
Magnesium is a recent addition to the plasmonic toolbox: nanomaterials that efficiently utilize photons' energy due to their ability to sustain localized surface plasmon resonances. Magnesium nanoparticles protected by a native oxide shell can efficiently absorb light across the solar spectrum, making them a promising photocatalytic material. However, their inherent reactivity toward oxidation may limit the number of reactions in which Mg-MgO can be used. Here, we investigate the stability of plasmonic Mg-MgO core-shell nanoplates under oxidative conditions. We demonstrate that the MgO shell stabilizes the metallic Mg core against oxidation in air at up to 400 °C. Furthermore, we show that the reactivity of Mg-MgO nanoplates with water vapor (3.5 vol % in N) decreases with temperature, with no oxidation of the Mg core detected from 200 to 400 °C. This work unravels the potential of Mg-MgO nanoparticles for a broad range of catalytic transformations occurring in oxidative environments.
PubMed: 38814251
DOI: 10.1021/acs.nanolett.4c01720 -
Nutrients May 2024Endothelial dysfunction is a crucial event in the early pathogenesis of cardiovascular diseases and is linked to magnesium (Mg) deficiency. Indeed, in endothelial cells,...
Endothelial dysfunction is a crucial event in the early pathogenesis of cardiovascular diseases and is linked to magnesium (Mg) deficiency. Indeed, in endothelial cells, low Mg levels promote the acquisition of a pro-inflammatory and pro-atherogenic phenotype. This paper investigates the mechanisms by which Mg deficiency promotes oxidative stress and affects endothelial behavior in human umbilical vascular endothelial cells (HUVECs). Our data show that low Mg levels trigger oxidative stress initially by increasing NAPDH oxidase activity and then by upregulating the pro-oxidant thioredoxin-interacting protein TXNIP. The overproduction of reactive oxygen species (ROS) activates NF-κB, leading to its increased binding to the inducible nitric oxide synthase (iNOS) promoter, with the consequent increase in iNOS expression. The increased levels of nitric oxide (NO) generated by upregulated iNOS contribute to disrupting endothelial cell function by inhibiting growth and increasing permeability. In conclusion, we provide evidence that multiple mechanisms contribute to generate a pro-oxidant state under low-Mg conditions, ultimately affecting endothelial physiology. These data add support to the notion that adequate Mg levels play a significant role in preserving cardiovascular health and may suggest new approaches to prevent or manage cardiovascular diseases.
Topics: Humans; Nitric Oxide Synthase Type II; Human Umbilical Vein Endothelial Cells; Magnesium Deficiency; Oxidative Stress; Reactive Oxygen Species; Nitric Oxide; Magnesium; NF-kappa B; Carrier Proteins; Endothelium, Vascular
PubMed: 38794644
DOI: 10.3390/nu16101406