Search Results (277)

Environmental pH plays a critical role in microbial fermentation processes. Weizmannia coagulans attracts particular attention for exceptional acid tolerance and lactic acid productivity. Yet acidic stress impacts on its cell division regulation remain unclear. Here, a critical pH value (pH 4.20) for growth inhibition of the Gram-positive bacterium Weizmannia coagulans strain BC99 was first established. Transcriptomic analysis of metabolic pathways was then performed. The multi-layered regulatory network underlying acid stress-induced cell division was elucidated. Integrated transcriptomic and physiological analyses reveal that acid stress triggers multigene expression reprogramming. This drives core metabolic network reorganization, coordinately regulating division processes. RNA-seq analysis demonstrated acid stress triggered differential expression of division genes (FtsZ/Q downregulation), ATP synthase suppression, and peptidoglycan transport reduction, while enhancing membrane rigidification (Cfa) and magnesium homeostasis (CorA). The PhoPR dual-component system emerged as a central regulator, inhibiting septal assembly via RipA hydrolase and RpsU ribosomal suppression while rerouting carbon flux to glycolysis, elucidating bacterial acid adaptation mechanisms. Collectively, these adaptive changes prioritize cell survival over active proliferation under acidic conditions. This study provides molecular insights into how W. coagulans preserves viability under acid stress, offering a theoretical basis for optimizing its performance in probiotic applications. Full article

Manganese (Mn) is an essential micronutrient required for plant growth, photosynthesis and metabolic regulation. Its importance is related to the involvement in several metabolic processes that ensure proper cellular function and balanced plant development throughout the production cycle. In plants, Mn is absorbed predominantly as Mn²⁺, and its availability is strongly influenced by soil pH, aeration, and other mineral nutrients in the soil solution. After uptake by roots, Mn is translocated to the shoot, accumulating primarily in metabolically active organs such as stems, young leaves and flowers. Although Mn exhibits limited mobility in the phloem, adequate concentrations are necessary to sustain both vegetative development and reproductive growth. Adequate Mn concentration is directly reflected in fruit development, as well-nourished plants show improved flowering, greater assimilate translocation capacity, and better fruit filling, thereby positively influencing yield and quality. However, Mn deficiency is common in alkaline soils or soils with high organic matter, causing interveinal chlorosis in young leaves, reduced growth, and lower biomass production. Under prolonged conditions, deficiency leads to less vigorous plants with reduced metabolic efficiency. Conversely, Mn toxicity, typically associated with acidic and poorly drained soils, restricts root development and induces nutritional imbalances with other elements, such as calcium, magnesium, and iron. Therefore, proper Mn management is essential to ensure nutritional balance and optimal performance of agricultural crops. Overall, this review synthesizes advances in Mn transport, cellular compartmentalization, and metabolic regulation, emphasizing how Mn interacts with other mineral nutrients to influence plant physiology. Attention is given to the integration of Mn with redox networks, photosynthetic regulation, and reproductive development. By linking transport mechanisms with physiological outcomes, this review identifies key patterns governing Mn homeostasis and highlights implications for crop nutrition and sustainable nutrient management. Full article

Background: Neuropsychiatric disorders such as Alzheimer’s disease (AD), bipolar disorder (BD), and depression exhibit shared glutamatergic abnormalities, although their upstream molecular mechanisms remain poorly defined. Magnesium (Mg²⁺) serves as a key regulator of N-methyl-D-aspartate (NMDA) receptor function; however, the role of Mg²⁺ transporters, particularly SLC41A1, has not been systematically investigated. As NMDA receptor dysregulation contributes to emotional and cognitive impairments, elucidating Mg²⁺-NMDA signaling may enable the development of novel therapeutic strategies. Methods: We integrated Mendelian randomization, locus colocalization, human brain transcriptomics, functional enrichment, and co-expression analyses to determine whether SLC41A1 functions as a cross-disorder molecular driver. In addition, in vitro electrophysiological experiments using field potential recordings in hippocampal Schaffer-CA1 synapses were conducted to validate its functional role in NMDA receptor-mediated synaptic transmission. Results: Genetically elevated SLC41A1 expression increased the risk of AD, BD, depression, and alcohol dependence, with strong colocalization analyses supporting shared causal variants. Transcriptomic profiling revealed SLC41A1 upregulation in AD and BD, with enrichment in magnesium transport, mitochondrial function, and synaptic signaling pathways. Co-expression networks across GTEx brain regions demonstrated strong correlations with NMDA-related genes (e.g., GRINA, CAMK2G, GRIN2C). Under NMDAR-selective recording conditions, both imipramine treatment and SLC41A1 knockdown significantly reduced NMDAR-mediated fEPSP amplitudes, supporting a role for SLC41A1 in regulating NMDA receptor-dependent synaptic responses. Conclusions: This study identifies SLC41A1 as a magnesium-centered, transdiagnostic therapeutic target that links Mg²⁺ homeostasis to NMDA-dependent synaptic dysfunction. These findings provide a mechanistic foundation for developing SLC41A1-modulating or magnesium-based therapeutic approaches for mood and cognitive disorders. Full article

Magnesium is an essential macronutrient for both plants and humans. However, its availability in agricultural systems and dietary intake has been declining, raising concerns about crop productivity and nutritional security. In plants, magnesium plays a critical role in photosynthesis, enzyme activation, carbohydrate transport, and overall metabolic regulation, while in humans it is required for numerous biochemical processes related to energy metabolism, cardiovascular function, and disease prevention. Long-term studies have reported a 20–30% decrease in magnesium concentrations in fruits and vegetables worldwide, potentially contributing to widespread magnesium deficiency. Soil factors such as acidification, nutrient imbalance, and intensive agricultural practices further limit magnesium availability along the soil–plant–human continuum. This review summarizes the biological importance of magnesium in plants and humans, evaluates the occurrence and causes of magnesium deficiency, and discusses current strategies for improving magnesium nutrition through agronomic and genetic biofortification. It considers even fertilizer management, nano-fertilizers, and alternative magnesium sources such as serpentinite. The review highlights biofortification as a cost-effective and sustainable strategy to enhance crop magnesium concentration and mitigate global magnesium deficiency while emphasizing the need for further research on bioavailability, environmental safety, and long-term agricultural sustainability. Full article

With the development of science and technology, heat dissipation has become a bottleneck problem restricting the development of fields such as transportation, machinery, electronics, and aerospace. Aiming to resolve the bottleneck problem of low thermal conductivity in traditional commercial magnesium alloys, this paper designed alloy compositions to investigate the effects of the solid solubility of La and Ce, and the size, morphology, distribution, and volume fraction of the second phase in the microstructure of magnesium alloys during the heat dissipation performance of the Mg-RE binary system and the Mg-Mn-La(Ce) system. The research shows that through CAFE simulation calculations, regulation can be achieved via the following methods: increasing the average nucleation undercooling, which leads to larger grain sizes; reducing the nucleation density, which results in larger grain sizes; and increasing the standard deviation of the average nucleation undercooling, which reduces the area of small grains while increasing the area of large grains. The thermal conductivity of both as-cast and solid-solution Mg-La (Ce) binary alloys gradually decreases with the increase in the added elements. However, after solution treatment, the thermal conductivity of the Mg-La (Ce) binary alloys is higher than that of the as-cast alloys. The addition of the Ce element helps refine the as-cast microstructure of the Mg-0.5Mn alloy. With the increase in Ce addition, the volume fraction of the Mg12Ce phase also increases. The thermal conductivity of the as-cast Mg-0.5Mn-xCe alloy gradually increases with rising temperature. Meanwhile, at room temperature, the thermal conductivity of the as-cast Mg-0.5Mn alloy gradually decreases with the increase in Ce addition, and the rate of decline gradually slows down due to the precipitation of the Mg12Ce phase. Full article

Magnesium-sulfur (Mg-S) batteries present a compelling energy storage solution, characterised by their remarkable theoretical energy density and economic viability. Nonetheless, challenges arise, including swift capacity degradation and suboptimal polysulfide (acting as an electronic and ionic insulator) utilisation, mainly due to a phenomenon known as the polysulfide “shuttle effect.” This effect also leads to a decline in battery performance. The Becke, 3-parameter, Lee-Yang-Parr (B3LYP) functional and 6-311G (d,p) basis set were used to examine the optoelectronic and charge-transfer properties of a polyaniline-pyrrole (PANIPyr) composite, emphasising interatomic and electronic interactions that enhance charge transport and oxidation of MgS₂. The findings demonstrate the presence of coordination bonding between hydrogen in pyrrole and the N⁻ ion in quinonediimine of polyaniline, significantly enhancing the electrical properties of PANI. The PANIPyr_P1 (P1-pyrrole attached at position one) configuration exhibits the lowest Ɛ_gap and the highest charge-transfer capacity, compared to other studied molecules in this work, thereby improving reactivity towards polysulfides in comparison to pure PANI. Significant electrical interactions at this site establish accessible electrophilic and nucleophilic regions that stabilise the ionic sides of the polysulfides, thus reducing the shuttle effect and improving charge transport at the interface. PANIPyr_P1 demonstrates viability for minimising polysulfide migration and enhancing cathodic efficiency in Mg-S batteries, thereby laying a foundation for future investigations into polymer-based cathode modifiers. Full article

Using α-SiC powder as a raw material, with ytterbium oxide and magnesium oxide as liquid-phase sintering aids, silicon carbide ceramics were prepared via spark plasma sintering (SPS) at 1900, 2000, and 2050 °C with a 10 min dwell. As the sintering temperature increased, the grain size grew from 0.54 μm to 17.59 μm, while the thermal conductivity correspondingly increased from 122.4 W/(m·K) to 231.8 W/(m·K). Microstructural analyses revealed that elevated sintering temperatures significantly accelerated the dissolution–precipitation process, thereby inducing abnormal grain growth. Grain size is identified as the dominant factor governing the thermal conductivity of SiC ceramics. Larger grains reduce grain boundary density and interfacial thermal resistance, thereby facilitating phonon transport. Full article

Thiocyanate (SCN⁻), a persistent inorganic contaminant widely present in industrial wastewater, poses severe risks to plant growth and photosynthesis. Hydrogen sulfide (H₂S) is an emerging gaseous signaling molecule involved in the regulation of plant stress responses; however, its role in modulating Rubisco energy metabolism and activation under SCN⁻ stress remains unclear. Here, we investigated the effects of exogenous H₂S on magnesium homeostasis, ATP/NADPH metabolism, Rubisco activation, and photosynthetic performance in rice seedlings exposed to SCN⁻ stress via physiological, biochemical, and transcriptional approaches. We found that exogenous H₂S significantly increased Mg²⁺ accumulation, enhanced H⁺-ATPase and Mg²⁺-ATPase activities, and promoted Rubisco activase (RCA) abundance and activity. These changes were accompanied by reduced steady-state ATP and NADPH contents, indicating that increased energy consumption was driven by accelerated Calvin cycle turnover. At the transcriptional level, H₂S regulated key genes involved in ATP hydrolysis, Mg²⁺ transport, Rubisco activation, and chlorophyll biosynthesis. Consequently, the chlorophyll content, stomatal conductance, and transpiration rate improved under SCN⁻ stress. Collectively, our results demonstrate that exogenous H₂S enhances photosynthetic efficiency and Rubisco carboxylation capacity by coordinating Rubisco energy metabolism and activation. 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

The current research first investigates the flow in the fractional order of a vertical artery with atherosclerosis using a Casson-based penta-hybrid nanofluid. Gold (Au), copper (Cu), silver (Ag), magnesium oxide (MgO), and alumina (Al₂O₃) nanoparticles are dispersed in blood to make the hybrid nanofluid. It is assumed that the flow is very pulsatile. The mathematical model is constructed by using differential forms of the conservation laws of mass, momentum, energy, and irreversibility analysis. By applying the mild stenosis approximation, the governing equations are transformed into dimensionless form. To generalize the classical model to its fractional counterpart, the Caputo–Fabrizio fractional derivative (C-FFD) is employed. Closed-form solutions for the velocity and temperature fields are realized by the joint application of the Laplace and Hankel transforms. The impact of essential physical parameters on velocity, temperature, and entropy generation is displayed through figures. The physical significance of enhanced thermal characteristics is shown, emphasizing their potential relevance to thermal regulation, targeted drug delivery, and minimization of irreversible energy losses in biomedical flow systems. The velocity profile elevates with the increase in the Casson parameter, while the temperature drops as the fractional-order parameter rises. Entropy generation is observed to amplify with the increasing values of the thermodynamic parameter in question, whereas an opposite tendency is seen for the Bejan number. The Bejan number decreases as the control parameter becomes higher. The novelty of the present investigation lies in the simultaneous incorporation of Caputo–Fabrizio fractional dynamics, penta-hybrid nanoparticle suspension, and entropy generation analysis in a stenosed arterial configuration. Unlike existing fractional Casson blood flow models that primarily focus on single or hybrid nanofluids, the present framework highlights the synergistic enhancement of thermal transport and irreversibility control achieved through penta-hybrid nanoparticles, which may be relevant for advanced biomedical and targeted therapeutic applications. Full article

Magnesium ion (Mg²⁺), particularly its free intracellular form, is indispensable for regulating diverse cellular functions. This critical role implies the existence of dedicated transporters and channels in the plasma membrane that coordinate Mg²⁺ uptake, intracellular storage, and efflux to maintain homeostasis. Although numerous molecular entities responsible for such Mg²⁺ transport have been reported over the past decades, there is still limited knowledge of their precise functions and disease implications. This review focuses on the solute carrier family 41 (SLC41), which consists of three isoforms (A1, A2, and A3) that share homology with the prokaryotic magnesium transporter E (MgtE) Mg²⁺ transporter family. Accumulating evidence has established SLC41A1 as the Na⁺/Mg²⁺ exchanger—a predominant Mg²⁺-efflux system. By contrast, the subcellular site of SLC41A2-mediated Mg²⁺ flux remains undefined, with potential roles at either the plasma membrane or organellar membranes, and SLC41A3 facilitates Na⁺-dependent Mg²⁺ efflux from mitochondria. Additionally, several studies have reported the association between SLC41s and diseases, including Parkinson’s disease, hepatocellular carcinoma, and nephronophthisis-related ciliopathies. By synthesizing current knowledge, this review aims to enhance the understanding of SLC41 transporters in health and disease and to explore their potential as therapeutic targets for clinical intervention. Full article

Background/Objectives: Magnesium (Mg²⁺) supplements can contain different types of Mg²⁺ salts, which influence their bioavailability. A highly bioavailable and bioaccessible Mg²⁺ source is essential to meet requirements for many physiological processes that are fundamental to human health. The objective of this study was to compare the bioavailability of Mg²⁺ from different sources, with different composition and chemical structure, namely, Aquamin Mg Soluble (seawater), magnesium oxide, commercial magnesium bisglycinate 1, and analytical grade magnesium bisglycinate 2. In addition, the influence of the different Mg²⁺ sources on transported Mg²⁺ and expression of TRPM6 and TRPM7 genes in Caco-2 cell monolayers was also evaluated to estimate bioavailability. TRPM6 and TRPM7 are members of the transient receptor potential melastatin subfamily characterized as Mg²⁺ permeable channels. Method: The study involved analyzing bioavailability of the Mg²⁺ sources predigested with and without food using the Infogest model prior to application to a Caco-2 cell monolayer in transwells for assessing transport. Mg²⁺ concentration on the basolateral side was analyzed by ICP-MS, and expression of TRPM6 and TRPM7 genes in the monolayer was analyzed using real-time qPCR. Results: Aquamin Mg Soluble showed significantly higher bioavailability compared to magnesium bisglycinate 2 (p = 0.016) when digested with food prior to application to the Caco-2 monolayer. In the digestion without food prior to the Caco-2 monolayer, there was no significant difference between Mg²⁺ bioavailability among the tested supplements. The TRPM6 gene was significantly downregulated in Caco-2 monolayers exposed to Aquamin Mg Soluble compared to untreated Caco-2 cells (p < 0.001). Conclusions: The INFOGEST digestion model showed that Aquamin Mg Soluble provides a highly bioavailable form of Mg²⁺, while the Caco-2 monolayer model also demonstrated its increased bioavailability by the modulation of TRPM6 gene expression. Full article

Ultrapotassic lamprophyre dykes are spatially closely related to gold deposits in collision tectonic belts. However, the potential implication of these lamprophyre dykes to gold deposits remains poorly constrained. Abundant ultrapotassic lamprophyre dykes in the Baiyun gold deposit of Liaodong Peninsula, NE China, are closely associated with Au orebodies. This presents an excellent opportunity to investigate the genesis and tectonic significance of these dykes, as well as their potential connection to gold mineralization. Here, based on LA-ICPMS zircon U-Pb age, petrogeochemistry, and Sr-Nd-Hf isotopic composition characteristics, we studied the ultrapotassic lamprophyre dykes in the Baiyun gold deposit. Zircon U-Pb dating of lamprophyre dykes is 225.7 ± 1.3 Ma, which is consistent with the previous auriferous pyrite Re-Os data results within error, indicating that the lamprophyre dykes and gold deposits formed simultaneously in the Late Triassic, which coincided with the exhumation of the deeply subducted South Chin Block (SCB). The lamprophyre dykes belong to the shoshonitic series (K₂O + Na₂O = 6.39–7.57 wt.%, K₂O/Na₂O = 3.99–8.74) and are enriched with magnesium (MgO = 5.33–6.40 wt.%, Mg^# = 58–65), barium (Ba = 2225–3046 ppm), and strontium (Sr = 792–927 ppm), and their (⁸⁷Sr/⁸⁶Sr)_i isotopic composition ranges from 0.712514 to 0.714831, ε_Nd(t) ranges from −15.4 to −14.1, and zircon ε_Hf(t) values range from −14.3 to −12.5. These correspond to Paleoproterozoic model ages between 2.1 and 2.3 Ga, which are comparable to the ultra-high-pressure metamorphic rocks with the SCB nature found in the Dabie–Sulu orogenic belt. The results demonstrate that the overlying lithospheric mantle was possibly metasomatized by subducted SCB-derived melts before magma generation under the North China Block (NCB) in the Late Triassic. The lamprophyre dykes with high Nb/U and Th/Yb values, enriched Ba, Sr, REE, Na₂O + K₂O, K₂O/Na₂O, and the LOI demonstrate that the metasomatic agents were hydrous, high-pressure melts. These melts likely resulted from the partial melting of subducted continental crust, which is attributed to phengite breakdown in the subduction continental channel. The silica-rich melts migrate from the plate into the sub-continental lithospheric mantle (SCLM) and form potassic- and volatile-enriched metasomatized SCLM. Subsequently, the partial melting of metasomatized SCLM due to the decompression and thinning may be the main mechanism to generate the syn-exhumation ultrapotassic magma in a post-collision setting. This study suggests that the SCLM, metasomatized by melts derived from continental crust, plays a key role in generating volatile-rich hydrous SCLM during the continental subduction and collision stage. In contrast, during the post-collision stage, as tectonic forces transition from compressional to extensional, the abundant volatiles and ultrapotassic magma produced from the partially melted and metasomatized lithospheric mantle may significantly contribute to the transportation, enrichment, and precipitation of gold through magmatic-hydrothermal processes, facilitating the formation of gold deposits. Full article

In the current context of climate change, special attention should be paid to assuring the security of food and fruits. Lemon trees struggle to keep their physiological traits stable in the context of all the cumulated challenges originating from climate stress. Therefore, our aim was to assess two seed priming methods’ long-term effects on some physiological parameters of young lemon trees. The relative chlorophyll content reveals that hydropriming shows 26% increases from E1 to E6, similar to the control, while osmopriming has a 31% higher value at the beginning and after three years. Leaf stomatal density has 80% lower values due to osmopriming compared to the control, while hydropriming show 15% lower values. Leaf area development was slightly similar between treatments, with more leaves being developed after hydropriming treatments. Guard cell width has similar values for priming, with both being with 40% higher than that of the control. Lemon trees grown after osmotic stress have the highest mass percentages of magnesium and potassium in the leaves. Hydropriming promotes calcium oxalate accumulation and a high mass percentage of phosphorus. The percentage allocation of carbon as dry matter is 32% for osmopriming, significantly higher than for the other treatments. The quantum yield of photosynthetic electron transport is the only significant photosynthetic parameter for osmoprimed lemon young trees. Physiological techniques successfully enhanced the overall growth of three-year-old lemon trees, especially osmopriming treatment. Full article

Dysregulated magnesium (Mg²⁺) homeostasis contributes to colorectal cancer (CRC), yet its context-dependent function within the tumor microenvironment remains unresolved. This study aimed to determine how sustained low and high extracellular Mg²⁺ environments affect CRC spheroid (SP) growth and Mg²⁺ homeostasis using HT-29 SPs. We analyzed Mg²⁺ flux, the expression of Mg²⁺ transporters (e.g., Transient Receptor Potential Melastatin (TRPM) 6), viability, apoptotic and autophagic markers, and phospho-/oxidoproteomic alterations. Both Mg²⁺ extremes destabilized SP architecture, reduced viability, and induced apoptosis and autophagy, with SPs displaying heightened vulnerability relative to 2D cultures. Mg²⁺ stress impaired Mg²⁺ influx and eliminated adaptive transporter regulation in SPs. Loss of membrane TRPM6/7 heterodimers, driven by altered phosphorylation (e.g., TRPM6 Serine 141, Serine 1252, Threonine 1851) and elevated oxidation (e.g., Methionine 1755), suppressed channel activity. High Mg²⁺ caused profound metabolic failure despite increased total Mg²⁺, reflecting functional Mg²⁺ deficiency. CRC spheroids are acutely susceptible to Mg²⁺ imbalance due to collapsed transporter homeostasis and post-translational inhibition of Mg²⁺ channels. These findings reveal a targetable metabolic vulnerability and support the therapeutic potential of localized Mg²⁺ modulation in CRC. Full article