Search Results (370)

Background: Obesity is commonly seen as a condition of overnutrition; however, it is paradoxically associated with micronutrient deficiencies. These deficiencies are clinically relevant and may contribute to the progression of obesity-related comorbidities through interconnected pathways, including chronic low-grade inflammation, oxidative stress, gut dysbiosis, and impaired nutrient absorption. Objectives: This narrative review aims to summarize current evidence regarding the prevalence, underlying mechanisms, and clinical consequences of micronutrient deficiencies in individuals with obesity, with particular emphasis on their metabolic implications and potential therapeutic strategies. Results: Among individuals with obesity, iron, zinc, magnesium, calcium, vitamin D, vitamin B12, and folate are the most frequently reported deficiencies. These deficiencies arise from multiple mechanisms, including poor diet quality, increased metabolic demands, and compromised gastrointestinal absorption. In addition, obesity-related alterations in pharmacokinetics may further interfere with micronutrient distribution and bioavailability. Together, these mechanisms may lead to various clinical outcomes, such as anemia, immune, metabolic, and cardiovascular dysfunctions, along with cognitive impairment. Although several studies suggest that correcting these deficiencies may improve clinical outcomes, findings remain inconsistent, highlighting the complex and multifactorial pathophysiology underlying micronutrient imbalance in obesity. Conclusions: Micronutrient deficiencies represent frequently overlooked contributors to metabolic dysregulation in obesity. Their identification and correction should be considered a central part of the obesity management strategy. A personalized supplementation approach, based on clinical, biological, and pathophysiological characteristics, may provide a complementary support for weight-management treatments. Full article

A composite meeting the UL94 V-0 rating was produced by adding 30 wt% epoxy silane-modified aluminum trihydrate (EPATH) to a 60/40 epoxy/benzoxazine matrix. Various bimodal and trimodal composites containing 20–40 wt% of three types of ceramic fillers, i.e., aluminum oxide (Al₂O₃), boron nitride (BN), and magnesium oxide (MgO), were prepared to simultaneously achieve flame-retardant and thermal conductive properties. The bimodal composites with 40 wt% of Al₂O₃ and MgO exhibited thermal conductivities of 1.22 W/m∙K and 1.29 W/m∙K, respectively, which were superior to that of the composite containing the same amount of ATH (1.0 W/m∙K). In contrast, both the coefficient of thermal expansion (CTE) and shear strength decreased with increasing ceramic filler content. For agglomerated BN, the filler loading was constrained above 30 wt% because its high specific volume caused a significant rise in the viscosity. In the trimodal composites with a total filler content of 40 wt% of Al₂O₃ and BN, a BN fraction of 7.5 wt% yielded the highest thermal conductivity of 1.64 W/m∙K and the lowest water absorption of 0.69%. When the trimodal composites were exposed to −55 °C and 150 °C for 1000 h, they exhibited a reduction in shear strength of less than 30% compared to their initial values. Full article

The growing interest in functional beer production has led to the exploration of unconventional raw materials, such as hemp (Cannabis sativa L.), for brewing applications. This study aimed to evaluate the volatile organic compound (VOC) profile and the macro- and microelement composition of barley wort enriched with varying proportions (10% and 30%) of malted and unmalted hemp seeds, using solid-phase microextraction followed by gas chromatography–mass spectrometry (SPME–GC–MS) and atomic absorption spectrometry (AAS). A total of 64 VOCs were identified across four wort variants: control (barley malt only), 10% malted hemp, 30% malted hemp, and 30% unmalted hemp. The aroma profile was significantly influenced by compounds such as 2,3-butanediol, 1-hexanol, 3-methyl-1-butanol, 3-hydroxy-2-butanone, hexanoic acid, and 4-vinylguaiacol (p < 0.001). Principal component analysis (PCA) revealed clear separation between wort types based on the relative abundance of alcohols, acids, ketones, and phenols, indicating a progressive shift from sweet/malty toward acidic, green, and herbal aroma notes as hemp addition increased. Notably, unmalted hemp seeds resulted in a pronounced dominance of hexanoic acid, which may contribute to earthy and rancid sensory attributes. The evaluation of selected mineral elements showed that the key macroelements differentiating the worts were potassium, magnesium, phosphorus, and calcium, while among the microelements the distinguishing elements were manganese, iron, and sodium. These findings demonstrate the strong modulating effect of aromatic hemp-derived materials on the aroma composition and selected mineral content of brewing worts, supporting their targeted use in novel beer formulations. Full article

Sea turtles are increasingly being used as bioindicators of marine pollution, yet baseline data on trace elements in the blood are still limited. This study quantified magnesium (Mg), iron (Fe), zinc (Zn), copper (Cu), cadmium (Cd) and lead (Pb) in green turtles (Chelonia mydas) (55 plasma samples and 71 cell concentrate samples) and olive ridleys (Lepidochelys olivacea) (101 plasma samples and 65 cell concentrate samples) sampled off the Caribbean (Tortuguero) and Pacific (Ostional) coasts of Costa Rica in 2003–2004. The metals were measured using atomic absorption spectroscopy; whole-blood concentrations were derived from the plasma and the erythrocyte values. The present results were compared with published datasets to evaluate the spatial and temporal patterns of metal exposure over the past two decades. The essential elements showed matrix-specific distributions, with Mg and Cu higher in the plasma, and Fe and Zn higher in the cell concentrates in both species (p < 0.001). C. mydas generally exhibited higher Cu, Fe and Zn levels in the plasma (p < 0.001), whereas L. olivacea showed markedly higher Cd levels (p < 0.001). Overall, the Pb levels were low as compared with many other rookeries worldwide. These data provide one of the earliest, large-sample baselines for trace elements in sea turtle blood in the Eastern Tropical Pacific and Western Caribbean and underscore the value of blood-fraction analysis for long-term ecotoxicological monitoring. Full article

Trifoliate orange (Poncirus trifoliata L.) is one of the most widely utilized rootstocks in citrus production; however, it exhibits a relatively high sensitivity to salt stress. When cultivated in salinized soil, it frequently develops nutrient uptake disorders, leaf chlorosis, as well as reduced fruit yield and quality. To enhance the salt stress tolerance of citrus plants, this study investigated the effects of Trichoderma harzianum inoculation on the growth and response mechanisms of citrus seedlings under salt stress conditions. The results showed that salt stress significantly inhibited the growth of citrus seedlings, while T. harzianum inoculation effectively alleviated the inhibitory effect. After treatment with T. harzianum, the plant height, stem diameter, leaf number, and biomass of citrus seedlings increased significantly. The net photosynthetic rate, stomatal conductance, intercellular CO₂ concentration, transpiration rate, and chlorophyll content were significantly increased by T. harzianum inoculation. Meanwhile, T. harzianum inoculation increased the content of nitrogen, phosphorus, calcium, magnesium, zinc, and copper, and decreased sodium content in citrus seedlings. In addition, T. harzianum inoculation significantly up-regulated the expression of stress-responsive genes such as SOSs, PIPs, TIP1, TIP4, and TIP9. In conclusion, T. harzianum inoculation improved the salt stress tolerance of citrus seedlings through increasing photosynthetic efficiency, promoting nutrient absorption, sodium efflux, and water utilization via up-regulating the expression of SOSs and aquaporin genes. Full article

Mixed-anion silicate–phosphate oxysulfide glasses have attracted increasing interest due to their tunable thermal stability, electrical response, and potential use in functional glass and glass–ceramic materials. In this work, silicate–phosphate oxysulfide glasses in the SiO₂-P₂O₅-K₂O-MgO-SO₃-ZnO system were examined to determine how partial substitution of MgO with ZnO influenced their thermal and electrical properties under reducing conditions. Melting in a strongly reducing atmosphere predominantly converted sulfur to reduced sulfur species, producing mixed oxygen–sulfur glass networks. Differential scanning calorimetry (DSC) shows that ZnO substitution reduces the configurational heat capacity at the glass transition (ΔC_p) by up to ~40%, suppresses crystallization exotherms, and shifts crystallization onset temperatures by more than 100 °C toward higher values, indicating enhanced network rigidity. Potassium and magnesium K-edge X-ray absorption spectroscopy (XAS) revealed increased short-range ordering around Mg²⁺ in Zn-free glasses after heat treatment, whereas Zn-containing glasses remain more structurally disordered. Impedance spectroscopy demonstrated that ZnO-substituted glasses exhibit higher activation energies for electrical transport (≈0.9–1.0 eV) and lower AC conductivity compared to Zn-free compositions, reflecting restricted alkali-ion mobility. These results demonstrate that partial substitution of MgO with ZnO significantly enhances the thermal stability and electrical insulating behavior of reduced silicate–phosphate oxysulfide glasses, providing valuable structure–property insights for the design of thermally stable functional glasses and glass–ceramics. Full article

This study presents the development of an environmentally benign and economically viable methodology for the synthesis of graphene-containing carbon materials derived from renewable agricultural residues, specifically walnut shells, rice husks, and apricot stones. The proposed synthesis route involves sequential stages of controlled pre-carbonization, desilicification, chemical activation with potassium hydroxide (KOH), and subsequent mild exfoliation, resulting in the formation of few-layer graphene with a high degree of structural ordering. Pre-carbonization carried out at 523–573 K, followed by activation at 1123 K, yields graphene sheets exhibiting a specific surface area of 1300–1800 m²/g, a carbon content of 60–90%, and an average pore diameter below 100 nm. The synthesized materials were subjected to comprehensive physicochemical characterization using BET surface area analysis, Raman spectroscopy, FTIR spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic absorption flame emission spectrophotometry. Raman spectroscopic analysis revealed an I_G/I_2D intensity ratio of approximately 1.5–2.0, indicating the presence of graphene structures consisting of approximately four to five layers. To enhance adsorption performance, the graphene-containing carbon materials were further functionalized with sulfuric acid, and the successful incorporation of surface functional groups was confirmed by FTIR spectroscopy. The adsorption properties of the functionalized graphene-containing carbon materials were evaluated in aqueous solutions containing sodium, potassium, calcium, and magnesium salts, demonstrating adsorption efficiencies of up to 80%. Compared to conventional biomass-derived graphene synthesis methods, the developed approach produces materials with enhanced porosity, higher graphitic ordering, and improved chemical purity. These characteristics highlight the strong potential of the synthesized graphene-containing carbon materials for applications in energy storage systems, adsorption-based water purification technologies, and environmentally sustainable nanotechnological applications. Full article

Aloe vera (Aloe barbadensis Miller) represents a rich natural source of water, minerals, polysaccharides, vitamins, phenolic compounds and bioactive molecules that exert multiple health-promoting effects relevant to athletic performance. Its high content of water and minerals (magnesium, calcium, potassium) supports hydration and electrolyte balance during physical activity. At the same time, polysaccharides, especially acemannan, contribute to tissue regeneration, muscle recovery, immune modulation and gastrointestinal protection. Antioxidant compounds reduce exercise-induced oxidative stress, potentially improving recovery and limiting inflammatory damage. Aloe vera-based beverages, including leaf juices and fermented formulations, offer a practical and palatable vehicle for delivering these bioactives. In addition to supporting gut integrity and reducing symptoms such as reflux and heartburn, Aloe vera supplementation may enhance nutrient absorption and modulate glucose metabolism, contributing to better metabolic stability during exercise. The increasing commercial interest in natural functional beverages highlights the relevance of Aloe vera as a nutraceutical candidate for athletes. This review explores the multiple benefits of Aloe leaf derivatives, bridging traditional medicine and evidence-based applications for metabolic health (gastrointestinal comfort, hydration, antioxidant defence and post-exercise recovery). However, further clinical studies are needed to fully define dosage, efficacy and mechanisms of action. Full article

We report on the study of the immobilization process of non-radioactive rhenium (Re), a chemical analogue of technetium-99 (⁹⁹Tc), in compounds based on magnesium potassium phosphate (MKP), as well as the possibility of enhancing their properties with iron-bearing additives/fillers. Powdered Re₂O₇ was used as the initial Re-containing source. Because of the solubility and high leachability of Tc (VII), which is also volatile at high temperatures, its immobilization for long-term storage and disposal poses a serious challenge to researchers. Taking this into account, low-temperature stabilization technology based on MKP, a cementitious material, is currently considered promising. We prepared experimental specimens based on Re-incorporated MKP matrices and analyzed their microstructure in detail using analytical methods of X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Considering that iron-bearing substances can reduce Tc (VII) to the lower-valence form Tc (IV), which is more stable, attention was also paid to evaluate the effect of fillers (Fe₂O₃, Fe₃O₄, Fe, FeS and blast furnace slag (BFS)) on strength, oxidation state, and water resistance (expressed as leaching cumulative concentration). The addition of fillers ensures the formation of denser compounds based on MKP after 28 days of curing under ambient conditions and increases their mechanical strength. The oxidation state of Re and the reduction from Re (VII) to Re (IV) was estimated using X-ray-absorption near-edge structure (XANES) analysis. Considering the Re leaching concentrations from tests using the ANS-16.1 standard in water, enhanced leachability indices (LI) for Re from MKP matrices were determined with the addition of iron-bearing fillers. Overall, the average LI values were greater than the minimum limit, indicating their acceptance for disposal recommended by the U.S. Nuclear Regulatory Commission. Full article

Magnesium has significant potential for hydrogen storage in the solid state because its capacity is about 7.6 wt%. However, the high stability of magnesium hydride requires operating temperatures superior to 380 °C for hydrogen release. It is well known that Ni could catalyze the hydrogen absorption and desorption in magnesium. In this study, carbon-coated nickel nanoparticles were employed as catalysts to enhance the hydrogen absorption and desorption kinetics of pre-hydrogenated magnesium particles. The carbon-coated nickel nanoparticles were uniformly dispersed across the surface of the pre-hydrogenated magnesium particles. In dehydrogenation at 375 °C and 350 °C, the best sample desorbs 4.90 and 4.1 wt%, respectively, in 10 min. After 45 cycles at 375 °C, the hydrogen desorption capacity is 4.91 wt%, indicating a retention capacity of 100%. Our results demonstrate that carbon-coated nickel nanoparticles can be effectively incorporated into pre-hydrogenated magnesium without the need for ball milling, significantly enhancing hydrogen absorption and desorption performance. Full article

Coral aggregate concrete (CAC) serves as a critical material for sustainable development in marine engineering, effectively addressing the shortage of aggregate resources in the construction of offshore islands and reefs. In this paper, the aggregate characteristics, static and dynamic mechanical properties and modification technology of CAC are systematically reviewed. Research indicates that the coral aggregates (CAs), due to its high porosity (approximately 50%), low bulk density (900–1100 kg/m³), and rough, porous surface, results in relatively low static compressive strength (20–40 MPa), insufficient elastic modulus, and significant brittleness in CAC. However, its dynamic performance shows the opposite advantage. Under impact loads, the energy absorption capacity is enhanced by 32.6–140.3%, compared to ordinary concrete (OC) due to the energy dissipation mechanism of pore platic deformation. Through the modification techniques, such as aggregate pre-treatment (acid washing/coating), incorporation of auxiliary cementitious materials (silica fume increases strength by 16.4%), fibre reinforcement (carbon fibres enhance flexural strength by 33.3%), and replacement with novel cementitious materials (magnesium sulphate cement improves chloride ion binding capacity by 90.7%), the mechanical properties and durability of CAC can be significantly optimised. This paper highlights gaps in current research regarding the high strain rate (>200 s⁻¹) dynamic response, multi-factor coupled durability in marine environments, and the engineering application of alkali-activated materials, providing theoretical basis for future research directions. Full article

The initial formation of corrosion products in pure humid air on magnesium alloys AZ91 and AZ31 was studied using infrared reflection absorption spectroscopy (IRRAS), infrared spectroscopic imaging, and SEM-EDS. The kinetics of corrosion product formation were monitored in situ with IRRAS during exposure to humid air (95% relative humidity) under two different CO₂ concentrations: low (≤1 ppm) and ambient (400 ppm). For low CO₂ concentrations, the primary corrosion product detected on both alloys was magnesium hydroxide (Mg(OH)₂). In contrast, under ambient CO₂ conditions (400 ppm), magnesium hydroxy carbonate was the dominant product. After 16 h of exposure, the amount of magnesium converted into corrosion products was approximately 8–10 times higher under low-CO₂ conditions compared to ambient levels. The smaller formation of corrosion products but increased magnesium carbonate formation on AZ91D is attributed to its higher aluminium content compared to AZ31. Corrosion attack and product formation were largely localised to the centre of the α-phase in AZ91D, with the β-phase likely serving as sites for cathodic reactions. Full article

Magnetite (Fe₃O₄) is an essential material for enhancing microwave absorption performance and is widespread and abundant as a solid solution in natural minerals and metallurgical slags. In this work, the effect of Mg²⁺ on the structure, stabilization, and microwave absorption performance of magnesium-containing magnetite (Mg_xFe_3−xO₄) was investigated. On the basis of experiments on the reactions of Fe₂O₃ and MgO under different levels of p_CO/(p_CO + p_CO2), Mg_xFe_3−xO_{4 (x=0.0,0.2,0.4,0.6,1.0)} was synthesized, and Mg²⁺ was found to inhibit the re-oxidation of magnetite. On this basis, the microwave absorption performance of various synthesized Mg_xFe_3−xO₄ samples was measured and analyzed, where Mg²⁺ was found to enhance the microwave absorption performance of Fe₃O₄, and the RL_min value of Mg_0.2Fe_2.8O₄ increased to −50.43 dB compared to that of −19.20 dB for Fe₃O₄. Furthermore, the enhancement mechanism of Mg²⁺ was revealed through impedance matching, dielectric and magnetic loss tangents, and magnetization curves, where the Mg²⁺ ions were found to accelerate the hopping of electrons and change the impedance matching of Mg_xFe_3−xO₄ to a more ideal state. Full article

The CO₂ absorption rate and total uptake by MgO aqueous suspensions were investigated in batch experiments by systematically varying MgO concentrations (0.5–5 wt.%), CO₂ flow rates (0.5–2 L/min), temperatures (278–363 K), NaCl salinities (0–7 wt.%), Na₂SO₄ and K₂SO₄ concentrations (0–10.5 wt.%), and gas–liquid mixing systems (pipe outlet and porous stone sparger). Results show that temperature strongly controls the carbonation process: increasing temperature above 303 K consistently reduced both the CO₂ absorption rate $\eta \left(t\right)$ and the total CO₂ uptake $V_{CO2}$ due to the destabilization of metastable Mg(HCO₃)₂ solutions and accelerated precipitation of less soluble hydrated magnesium carbonates. Under optimal low-temperature conditions (278–283 K, 1–1.5 wt.% MgO, sparger mixing, pure system), the average capture efficiency reached ≈ 35%, with maximum peaks over 70% and total CO₂ uptakes of ≈ 12–17 L. Adding NaCl at typical seawater levels (3.5–7 wt.%) slightly increased CO₂ uptake at temperatures above 323 K. Sulfate ions (Na₂SO₄ and K₂SO₄) were found to enhance the absorption rate at low concentrations (<2 wt.%) but reduce it at higher levels, with no significant impact on the total CO₂ uptake observed in this study. Using a CO₂ sparger significantly improved gas–liquid contact, achieving average CO₂ capture efficiencies ${\eta }_{max}\left(t\right)$ above 70% at low temperatures, compared to <20% with simple pipe bubbling. A direct comparison with Ca(OH)₂ aqueous carbonation confirmed that, despite its lower solubility and slower kinetics, MgO can outperform Ca-based systems under specific conditions. These results provide practical experimental benchmarks and process guidance for designing Mg-based aqueous carbonation systems, including applications that use brines, industrial wastewater or seawater. Full article

Background: Psoriasis vulgaris is a systemic immune-mediated disease marked by oxidative stress and disruptions in mineral homeostasis. This study evaluated the effect of 12-week cyclosporine A (CsA) therapy on serum micro-/macroelements and redox balance in adults with moderate–severe disease. Methods: Thirty-seven patients were prospectively assessed at baseline, day 42, and day 84. Disease severity was quantified using PASI and BSA. Serum copper, zinc, magnesium, calcium, iron, sodium, and potassium were measured by atomic absorption spectrometry. Total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI = TOS/TAS × 100) were determined spectrophotometrically. Results: CsA treatment produced significant clinical improvement, demonstrated by reductions in PASI and BSA. Parallel biochemical changes included decreased copper and increased zinc, magnesium, calcium, and iron levels toward reference ranges (all p < 0.0001). TAS increased, TOS decreased, and OSI was markedly reduced, indicating restored redox balance. The Cu/Zn ratio declined throughout therapy, and elevated magnesium at week 12 correlated with greater clinical improvement. Sodium and potassium levels remained stable. Subgroup analyses suggested differing biochemical responses in smokers, patients with diabetes, and individuals with obesity. Conclusions: CsA improves psoriasis severity while ameliorating systemic oxidative stress and mineral disturbances. The Cu/Zn ratio and serum magnesium may support personalized monitoring during CsA therapy. Full article