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Cadmium (Cd) and arsenic (As) co-contamination has threatened rice production and food safety. It is challenging to mitigate Cd and As contamination in rice simultaneously due to their opposite geochemical behaviors. Mg-loaded biochar with outstanding adsorption capacity for As and Cd was used for the first time to remediate Cd/As contaminated paddy soils. In addition, the effect of zero-valent iron (ZVI) on grain As speciation accumulation in alkaline paddy soils was first investigated. The effect of rice straw biochar (SC), magnesium-loaded rice straw biochar (Mg/SC), and ZVI on concentrations of Cd and As speciation in soil porewater and their accumulation in rice tissues was investigated in a pot experiment. Addition of SC, Mg/SC and ZVI to soil reduced Cd concentrations in rice grain by 46.1%, 90.3% and 100%, and inorganic As (iAs) by 35.4%, 33.1% and 29.1%, respectively, and reduced Cd concentrations in porewater by 74.3%, 96.5% and 96.2%, respectively. Reductions of 51.6% and 87.7% in porewater iAs concentrations were observed with Mg/SC and ZVI amendments, but not with SC. Dimethylarsinic acid (DMA) concentrations in porewater and grain increased by a factor of 4.9 and 3.3, respectively, with ZVI amendment. The three amendments affected grain concentrations of iAs, DMA and Cd mainly by modulating their translocation within plant and the levels of As(III), silicon, dissolved organic carbon, iron or Cd in porewater. All three amendments (SC, Mg/SC and ZVI) have the potential to simultaneously mitigate Cd and iAs accumulation in rice grain, although the pathways are different.
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Arsénico , Cadmio , Carbón Orgánico , Magnesio , Oryza , Contaminantes del Suelo , Suelo , Oryza/química , Cadmio/análisis , Cadmio/química , Carbón Orgánico/química , Contaminantes del Suelo/análisis , Arsénico/análisis , Suelo/química , Magnesio/química , Hierro/química , Restauración y Remediación Ambiental/métodosRESUMEN
In this study, we investigated improving the performance of a layered double hydroxide (LDH) for the adsorption of As(III) and As(V) by controlling the morphology of LDH crystals. The LDH was synthesized via a simple coprecipitation method using barely soluble MgO as a precursor and succinic acid (SA) as a morphological control agent. Doping the LDH crystals with carboxylate ions (RCOO-) derived from SA caused the crystals to develop in a radial direction. This changed the pore characteristics and increased the density of active surface sites. Subsequently, SA/MgFe-LDH showed excellent affinity for As(III) and As(V) with maximum sorption densities of 2.42 and 1.60 mmol/g, respectively. By comparison, the pristine MgFe-LDH had sorption capacities of 1.56 and 1.31 mmol/g for As(III) and As(V), respectively. The LDH was effective over a wide pH range for As(III) adsorption (pH 3-8.5) and As(V) adsorption (pH 3-6.5). Using a combination of spectroscopy and sorption modeling calculations, the main sorption mechanism of As(III) and As(V) on SA/MgFe-LDH was identified as inner-sphere complexation via ligand exchange with hydroxyl group (-OH) and RCOO-. Specifically, bidentate As-Fe complexes were proposed for both As(III) and As(V) uptake, with the magnitude of formation varying with the initial As concentration. Importantly, the As-laden adsorbent had satisfactory stability in simulated real landfill leachate. These findings demonstrate that SA/MgFe-LDH exhibits considerable potential for remediation of As-contaminated water.
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Arsénico , Hidróxidos , Óxido de Magnesio , Ácido Succínico , Contaminantes Químicos del Agua , Adsorción , Contaminantes Químicos del Agua/química , Cinética , Arsénico/química , Ácido Succínico/química , Hidróxidos/química , Óxido de Magnesio/química , Purificación del Agua/métodos , Modelos QuímicosRESUMEN
BACKGROUND: Rheumatoid arthritis (RA) is a chronic inflammatory joint disease with all-cause mortality increasing globally. Dietary magnesium (Mg), an anti-inflammatory nutrient, has been proven to be associated with the all-cause mortality. The association of dietary Mg intake and all-cause mortality in RA patients remains unknown. The aim of this study was to assess the association between dietary Mg intake and all-cause mortality in RA patients. METHODS: RA patients were extracted from the NHANES 1999-2018, and followed for survival through December 31, 2019. Dietary Mg intake data were obtained from 24-h dietary recall interview. The association between dietary Mg intake and RA patients' all-cause mortality was explored based on weighted univariate and multivariate Cox proportional hazard models and described as absolute risk difference (ARD), hazard ratios (HRs) and 95% confidence intervals (CIs). This association was further explored in subgroup analyses based on different age, gender and body mass index (BMI). RESULTS: Totally 2,952 patients were included. Until 31 December 2019, a total of 825 deaths were documented. RA patients with higher dietary Mg intake had a 11.12% reduction of all-cause mortality (ARD=-11.12%; HR = 0.74, 95%CI: 0.56-0.99) in the fully adjusted model, especially in female (HR = 0.68, 95%CI: 0.47-0.98), aged < 65 years (HR = 0.59, 95%CI: 0.37-0.94) and BMI ≤ 30 kg/m2 (HR = 0.62, 95%CI: 0.42-0.91). CONCLUSION: RA patients who consumed adequate dietary Mg from diet as well as supplements may had a lower risk of all-cause mortality.
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Artritis Reumatoide , Dieta , Magnesio , Encuestas Nutricionales , Humanos , Artritis Reumatoide/mortalidad , Femenino , Masculino , Persona de Mediana Edad , Magnesio/administración & dosificación , Anciano , Adulto , Modelos de Riesgos Proporcionales , Causas de Muerte , Mortalidad , Bases de Datos Factuales , Estados Unidos/epidemiología , Índice de Masa CorporalRESUMEN
Background and aims Laryngoscopy and intubation cause an increased sympatho-adrenergic pressor response, which can be detrimental to patients with coronary artery disease, hypertension, etc. Various drugs and manoeuvres have been tried to reduce the pressor response with acceptable results but the quest for the ideal drug still continues. Hence, we planned to compare the effects of magnesium sulfate with paracetamol and fentanyl with lignocaine on attenuating the hemodynamic responses due to direct laryngoscopy and intubation and to note the complications of these drugs. Methods We studied 60 adult patients of the American Society of Anaesthesiologists (ASA) physical status I and II of either sex, scheduled for elective surgery under general anaesthesia. The patients were randomly divided into two groups. Group A received 25 mg/kg magnesium sulphate mixed with paracetamol 1 gram IV (100 ml) given over 10 minutes before induction and Group B received 2 mcg/kg fentanyl and 1.5 mg/kg lignocaine, 3 minutes before intubation. All patients were uniformly pre-medicated, induced, and intubated as per standard protocol. Heart rate (HR) and systemic arterial pressures were recorded at baseline, after study drug infusion, after induction, and 1, 3, 5, 10, and 15 mins after intubation. Hemodynamic parameters were compared using repeated measures analysis of variance (ANOVA). In the post-hoc tests, p value < 0.05 was considered statistically significant. Results We observed the mean pre-op HR (p = 0.161) and mean HR one-minute post-induction (p = 0.144). The percentage change from baseline at one-minute post-induction was 9.7 in Group A and 15.2 in Group B. We observed the mean pre-op mean arterial pressure (MAP) (p = 0.119) and mean MAP one minute post-induction (p = 0.585). The percentage change from baseline at one-minute post-induction was 3.3 in Group A and 2.8 in Group B. The percentage change from baseline was found to be within 15%, for HR in Group A and for systolic blood pressure (SBP), diastolic blood pressure (DBP), and MAP in Group B. However, there was no statistically significant difference (p > 0.05) between the mean HR, SBP, DBP, and MAP between the time points. Conclusion In our study, both the combinations of drugs, magnesium sulphate with paracetamol (Group A drugs) and fentanyl with lignocaine (Group B drugs) were found to be equally effective (i.e. neither group was superior to the other) in attenuating the hemodynamic response to laryngoscopy and intubation.
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BACKGROUND: In various disease contexts, magnesium abnormalities are associated with acute kidney injury (AKI) incidence. However, this association remains unclear and has not been systematically investigated in patients with cirrhosis. Hence, we aimed to elucidate the association between admission serum magnesium levels and AKI incidence in intensive care unit (ICU)-admitted cirrhotic patients. METHODS: A retrospective cohort study was conducted using MIMIC-IV2.2 data, focusing on critically ill patients with cirrhosis. We employed univariable and multivariable logistic regression and restricted cubic spline analyses to robustly address our research objectives. To further substantiate the findings, subgroup and sensitivity analyses were also conducted. RESULTS: Among the 3,228 enrolled ICU-admitted cirrhotic patients, 34.4% were female, and the overall AKI incidence was 68.6% (2,213/3,228). Multivariable logistic regression analysis revealed an independent relationship between elevated serum magnesium levels and increased AKI risk (OR = 1.55 [95% CI = 1.15-2.09], p = 0.004). Compared with individuals with serum magnesium levels < 1.6 mg/dL, individuals with serum magnesium levels in Q2 (1.6-2.6 mg/dL) and Q3 (≥2.6 mg/dL) had adjusted ORs for AKI of 1.89 (95% CI = 1.34-2.65, p < 0.001) and 2.19 (95% CI = 1.27-3.75, p = 0.005), respectively. The restricted cubic spline analysis revealed that AKI risk increased linearly with increasing serum magnesium levels. Subgroup analysis revealed that the association between serum magnesium levels and AKI incidence was remarkably stable in subgroup analysis (all Pinteraction >0.05). CONCLUSIONS: High serum magnesium concentrations were significantly associated with an increased AKI risk in ICU-admitted patients with cirrhosis. Further randomized trials are needed to confirm this association.
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Lesión Renal Aguda , Unidades de Cuidados Intensivos , Cirrosis Hepática , Magnesio , Humanos , Lesión Renal Aguda/sangre , Lesión Renal Aguda/epidemiología , Lesión Renal Aguda/etiología , Femenino , Magnesio/sangre , Estudios Retrospectivos , Masculino , Persona de Mediana Edad , Cirrosis Hepática/sangre , Cirrosis Hepática/complicaciones , Unidades de Cuidados Intensivos/estadística & datos numéricos , Incidencia , Anciano , Factores de Riesgo , Enfermedad Crítica , Modelos Logísticos , Bases de Datos Factuales , AdultoRESUMEN
With excessive Mn(â ¡) and Cu(â ¡) pollution in aquatic environments posing potential health risks to inhabitants, the emergence of carbon capture, utilization and storage (CCUS) technology has promoted the improvement of heavy metal remediation technologies. Using hydrothermal sediment as a crystal seed, rhamnolipid was used to mediate biomimetic mineralization to prepare hydrated magnesium carbonate (HMC) composites to enhance the Mn(â ¡)/Cu(â ¡) adsorption performance of alginate hydrogels. Hydrothermal sediment is beneficial for accelerating biomimetic mineralization, while rhamnolipid can induce a crystalline phase transformation from dypingite to nesquehonite. The addition of sediment significantly enhanced the compressive mechanical properties and thermal stability of the hydrogels. The adsorption performances of the nesquehonite and dypingite hydrogels were better for Mn(II) and Cu(II), respectively. An increase in the amount of sediment improved the adsorption of Cu(II) by the hydrogels appropriately, resulting in stronger selectivity for Cu(II). The adsorption of Mn(II) and Cu(II) on the hydrogel beads was thermodynamically spontaneous. The inhibitory effects of sodium dodecyl benzene sulfonate (SDBS), fulvic acid (FA) and alginate on Cu(II) adsorption were more obvious than those of bovine serum albumin (BSA). Both the complexation of functional groups on alginate and mineralization by HMC participated in the adsorption of Mn(II) and Cu(II).
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Resin cement integrated with zein-incorporated magnesium oxide nanoparticles has previously been found to inhibit oral microbes and decrease bacterial biofilm. However, the bond strength and surface features of this biomaterial have yet to be investigated. The objective of this study was to evaluate the shear bond strength, mode of fracture, and surface roughness of resin cement modified with zein-incorporated magnesium oxide nanoparticles. Characterization of the cement was performed by X-ray diffraction, field emission scanning electron microscopy, and Fourier transform infrared spectroscopy. 126 human teeth were divided into 3 groups and cemented to lithium disilicate ceramic using resin cement with zein-incorporated magnesium oxide nanoparticles at concentrations of 0%, 1%, and 2% (n = 42). 21 samples of each group were subjected to the shear bond strength test, while the other 21 underwent thermocycling for 10,000 cycles before the test, after which all samples were evaluated for the mode of fracture. To assess surface roughness, resin cement disks were analyzed by a profilometer before and after undergoing thermocycling for 10,000 cycles. The shear bond strength of the cement with 1% and 2% nanoparticles was significantly higher than the control before thermocycling. The mode of fracture was found to be mainly adhesive with all groups, with the unmodified cement presenting the highest cohesive failure. There was no significant difference in surface roughness between the groups before or after thermocycling. The addition of zein-incorporated magnesium oxide nanoparticles to resin cement improved or maintained the shear bond strength and surface roughness of the resin cement.
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BACKGROUND: Laryngospasm is sustained closure of the airways and can be a life-threatening condition. Magnesium sulphate is postulated to reduce the incidence of laryngospasm if administered peri-operatively. This systematic review and meta-analysis was performed to assess the efficacy of magnesium sulphate in preventing peri-operative laryngospasm in paediatric patients undergoing non-cardiac surgery. METHODS: Four databases and a trial registry were searched. Inclusion criteria were paediatric patients undergoing general anaesthesia. Exclusion criteria were patients who underwent cardiopulmonary bypass during surgery. The intervention of interest was the peri-operative administration of magnesium sulphate. The intervention was compared to either a placebo or other pharmacological agent. The primary outcome was the incidence of laryngospasm. A meta-analysis of all studies was performed. Sub-group analysis was subsequently performed. RESULTS: A total of 953 patients from 13 trials were included in this study. Nine RCTs administered magnesium intravenously and 4 RCTs administered magnesium locally. Laryngospasm rates were 6% lower in the magnesium group (OR 0.48 [95% CI 0.25-0.96], p = 0.04) compared to control in the pooled data. Subgroup analysis showed laryngospasm rates were lower by 12.5% (Odds Ratio 0.26 [CI 0.09-0.76], p = 0.01) in the local magnesium group. Subgroup analysis of studies that only administered intravenous magnesium did not show a statistically significant difference in the incidence of laryngospasm (OR 0.73 [95% CI 0.33-1.63], p = 0.44). CONCLUSIONS: This review shows a potential role for magnesium in the prevention of laryngospasm in paediatric patients undergoing general anaesthesia. There is a correlation between local administration of magnesium and reduction in laryngospasm rates. Further studies are required to assess the efficacy of intravenous magnesium in prevention of laryngospasm. REGISTRATION: Prospective Register of Systematic Reviews (PROSPERO); PROSPERO ID CRD42022307868 (https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022307868).
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Inorganic sources of Mg are commonly used in dairy cow diets, but their availability varies significantly. This study assessed the relative availability of 4 commonly used inorganic Mg sources and a novel alkalinizing proprietary mineral blend [PMB; Multesium (GLC Minerals, LLC, Green Bay, WI, USA)]. The study was a duplicated 6 × 6 Latin square, with 12 nonlactating, non-pregnant Holstein dairy cows assigned to a square based on BW and parity. Cows were fed 90% of their voluntary DMI (diet contained 0.21% Mg). Each experimental period lasted 7 d. On d 2 of each period, urinary catheters were fitted. Total urine collection started on d 3 for 48 h with samples collected and measured every 12 h. On d 4, 30 g of Mg were administered as boluses with gelatin capsules: negative control (one empty capsule), magnesium oxide (MgO), magnesium sulfate (MgSO4), calcium magnesium hydroxide [CaMg(OH)4], calcium magnesium carbonate [CaMg(CO3)2], and PMB [a blend of Ca and Mg sources that includes CaMg(CO3)2, CaMg(OH)4, and MgO]. Blood samples were collected at 0, 1, 2, 3, 12, and 24 h after treatment administration on d 4 of each treatment period. Urine and blood samples were analyzed for Mg and Ca concentration. Statistical analyses were conducted with PROC GLIMMIX including treatment, time, period, square, treatment × time, treatment × period, and time × period as fixed effects, and cow nested within square as a random effect in the model. Urinary Mg excretion for 4 of the Mg sources studied [PMB, MgO, CaMg(OH)4, and MgSO4] increased significantly, representing an increase of at least 40.8% relative to control. The supplementation of CaMg(CO3)2 did not significantly increase relative to control. There were no significant changes in blood Mg concentration with treatment; but, a significant treatment × time effect was observed. Calcium-rich sources [PMB, CaMg(OH)4, CaMg(CO3)2] had lower blood Mg concentrations at 12 or 24 h after treatment than control and CaMg(CO3)2. Based on urinary Mg excretion 24 h after treatment, 4 of the Mg sources evaluated (including PMB) showed a similar availability, however, the availability of the commercial CaMg(CO3)2 source included in our study was similar to the negative control (no-supplemented cows).
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BACKGROUND: Intravenous administration of magnesium sulfate (MgSO4) to expectant individuals before childbirth, has been evaluated to reduce the likelihood of mortality and occurrence cerebral palsy in their offspring. Therefore, this systematic review and meta-analysis conducted to determine if were the prophylactic use of magnesium sulfate in women at risk for preterm delivery leads to decrease in the incidence of death or cerebral palsy. METHODS: A comprehensive search of electronic databases was done to identify relevant studies. Selection of eligible studies was based on predetermined inclusion criteria. Data extraction was performed, and the methodological quality of the selected studies was assessed using appropriate evaluative tools. A meta-analysis was carried out to estimate the overall effect of intravenous administration of magnesium sulfate on the incidence of death or cerebral palsy. RESULTS: A total of 7 studies met the inclusion criteria and were included in the final analysis. No significant publication bias was observed. The risk of fetal neurological impairment was significantly lower in the MgSO4 group compared to the control group relative risk (RR = 0.70, 95% CI: 0.56 to 0.87; I20%). However, neonatal mortality was not significantly associated with MgSO4 injection. (RR = 1.03, 95% CI: 0.88 to 1.21; I2 = 42%). Subgroup analysis was done based on the bolus dosage of MgSO4 and the duration of the trial follow-up. revealing a non-significant differences between-group. CONCLUSION: This study demonstrated that MgSO4 administration can improve fetal neurological impairment and cerebral palsy but is not linked to reducing mortality. Further studies are necessary to strengthen the evidence and clarify the underlying mechanisms.
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Parálisis Cerebral , Sulfato de Magnesio , Fármacos Neuroprotectores , Ensayos Clínicos Controlados Aleatorios como Asunto , Femenino , Humanos , Recién Nacido , Embarazo , Parálisis Cerebral/etiología , Parálisis Cerebral/prevención & control , Sulfato de Magnesio/uso terapéutico , Sulfato de Magnesio/administración & dosificación , Fármacos Neuroprotectores/uso terapéutico , Fármacos Neuroprotectores/administración & dosificación , Nacimiento PrematuroRESUMEN
BACKGROUND: Numerous studies have shown inverse associations between serum magnesium (Mg) and risk of cardiovascular disease (CVD), but studies of dietary Mg have not been consistent. AIM: To examine the association of a Mg-rich diet score with risks of CVD, coronary heart disease (CHD), and ischemic stroke in the Atherosclerosis Risk in Communities (ARIC) study. METHODS: There were 15,022 Black and White adults without prevalent CVD at baseline (1987-89) included in this analysis. Diet was assessed at two visits 6 years apart using an interviewer-administered 66-item food frequency questionnaire. A Mg-rich diet score was created that included servings of whole grain products, nuts, vegetables, fruit, legumes, coffee, and tea. Cox proportional hazard regression evaluated associations of incident CVD, CHD and stroke across quintiles of Mg-rich diet score, adjusting for demographics, lifestyle factors, and clinical characteristics. RESULTS: Over >30 years of follow-up, there were 3,531 incident CVD events (2,562 CHD, 1,332 ischemic stroke). Participants who consumed more Mg-rich foods were older, female, White, had lower blood pressure, fewer were not current smokers, and more reported being physically active. A Mg-rich diet was inversely associated with incident CVD (HRQ5 vs Q1=0.87, 95%CI: 0.77-0.98, ptrend=0.02) CHD (HRQ5 vs Q1=0.82, 95%CI: 0.71-0.95, ptrend=0.01); however, the diet-stroke association was null (HRQ5 vs Q1=1.00, 95%CI: 0.82-1.22, ptrend=0.97). CONCLUSIONS: Consuming a diet including Mg-rich foods, such as whole grains, nuts, vegetables, fruits, legumes, coffee and tea, is associated with lower risk of CVD and CHD, but not ischemic stroke.
This study showed an inversely association between a magnesium-rich (mg-rich) diet score and risk of cardiovascular disease (CVD) in adults aged 45-64 at baseline (1987-89) and followed for over 30 years. The mg-rich diet score was created by summing the reported number of daily servings consumed from whole grain products, fruit, vegetables, legumes, nuts, coffee and tea.A mg-rich diet score may be associated with lower risk of developing CVD and coronary heart disease, but not ischemic stroke.
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Magnesium, an essential mineral for various physiological functions, is subject to tight regulation within the body. Understanding its absorption across epithelial cell monolayers is crucial for optimizing dietary magnesium intake and therapeutic strategies. The Caco-2 monolayer model, widely recognized for its relevance to the human intestinal epithelium, provides a suitable platform for this investigation. This protocol covers the step-by-step procedures for the cultivation of Caco-2 monolayer preparation of transwell systems. It provides guidance on the setup of magnesium transport experiments, which involve the application of magnesium salts to the apical side of the Caco-2 monolayer and monitoring their transport to the basolateral side.
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Mucosa Intestinal , Magnesio , Humanos , Células CACO-2 , Mucosa Intestinal/metabolismo , Magnesio/metabolismo , Permeabilidad , Transporte Biológico , Técnicas de Cultivo de Célula/métodos , Absorción Intestinal/efectos de los fármacos , Sales (Química)/metabolismoRESUMEN
Magnesium alloys have been extensively studied as degradable biomaterials for clinical applications due to their biocompatibility and mechanical properties. However, their poor corrosion resistance can lead to issues such as osteolysis and the release of gaseous hydrogen. This study investigated the influence of the activation time of magnesium surfaces in a sodium hydroxide (NaOH) solution on the concentration of active hydroxyl groups and corrosion resistance. The results indicated that immersion time significantly influences the formation of a corrosion-resistant film and the distribution of surface hydroxyl groups. Specifically, specimens treated for 7.5 h exhibited the highest concentration of hydroxyl groups and the most uniform oxide film distribution. Electrochemical tests demonstrated capacitive behavior and passive surface formation for all evaluated times, with the 7.5-h immersion in NaOH yielding superior corrosion resistance, lower current density, and a more efficient and thicker protective film. SEM and EDS analyses confirmed increased formation of Mg(OH)2 for samples treated for 5 and 7.5 h, while a 10-h treatment resulted in a brittle, porous layer prone to degradation. Statistical analysis using ANOVA and Fisher's LSD test corroborated these findings. The optimal 7.5-h alkali treatment enhanced magnesium's corrosion resistance and surface properties, making it a promising candidate for orthopedic implants. However, further studies are necessary to assess biocompatibility and physiological responses before clinical implementation.
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Rechargeable magnesium batteries (rMBs) are promising candidates for next-generation batteries in which sulfides are widely used as cathode materials. The slow kinetics, low redox reversibility, and poor magnesium storage stability induced by the large Coulombic resistance and ionic polarization of Mg2+ ions have obstructed the development of high-performance rMBs. Herein, a Cu1.8S1-xSex cathode material with a two-dimensional sheet structure has been prepared by an anion-tuning strategy, achieving improved magnesium storage capacity and cycling stability. Element-specific synchrotron radiation analysis is evidence that selenium incorporation has indeed changed the chemical state of Cu species. Density functional theory calculations combined with kinetics analysis reveal that the anionic substitution endows the Cu1.8S1-xSex electrode with favorable charge-transfer kinetics and low ion diffusion barrier. The principal magnesium storage mechanisms and structural evolution process have been revealed in details based on a series of ex situ investigations. Our findings provide an effective heteroatom-tuning tactic of optimizing electrode structure toward advanced energy storage devices.
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Bismuth-based compounds based on conversion-alloying reactions of multielectron transfer have attracted extensive attention as alternative anode candidates for rechargeable magnesium batteries (rMBs). However, the inadequate magnesium storage capability induced by the sluggish kinetics, poor reversibility, and terrible structural stability impedes their practical utilization. Herein, monodispersed Bi2S3 anchored on MXene has been prepared via a simple self-assembly strategy to induce the interfacial bonding of Ti-S and Ti-O-Bi. Unique superiority, including good electrical conductivity, high mechanical strength, and rapid charge transfer, is cleverly integrated together in the Bi2S3/MXene heterostructures, which endowed heterostructures with enhanced magnesium storage performance. Density functional theory calculations combined with kinetic behavior analyses confirm the favorable charge transfer and low ion diffusion barrier in hybrids. Furthermore, a stepwise insertion-conversion-alloying reaction mechanism is revealed in depth by ex situ investigations, which may also account for promoting performance. This work provides significant inspirations for constructing ingenious multicompositional hybrids by strong interfacial coupling engineering toward high-performance energy storage devices.
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Herein, we report for the first time a simple strategy to design a hierarchical chemically exfoliated magnesium diboride and guar gum network structure decorated with Ru nanoparticles (eMgB2-GG@Ru) as an electrode to evaluate its electrochemical performance for the application of supercapacitor. The eMgB2 and functionalized eMgB2-GG@Ru materials were thoroughly examined using XRD, TGA, DLS, FE-SEM, STEM, AFM, XPS, and BET techniques. The combined eMgB2-GG@Ru electrode exhibits a network structure morphology with an increased interlayer distance of eMgB2 nanolayers along with a uniform distribution of spherical Ru nanoparticles. The electrochemical performance of eMgB2-GG@Ru and its pristine materials was studied through CV, GCD, and EIS to determine their supercapacitor performance. The eMgB2-GG@Ru electrode demonstrates higher specific capacitance (352 F/g) than its eMgB2@Ru (258.9 F/g), and MgB2 (214.5 F/g) counterparts at a current density of 0.5 A/g in a three-electrode setup using 3 M KOH electrolyte. The hierarchical eMgB2-GG@Ru solid-state symmetric devices maintained higher capacity retention of 89 % even after 7000 cycles, achieving a maximum energy density of 26.12 kW/kg at the power density of 450 W/kg at 0.5 A/g. Therefore, the innovative eMgB2-GG@Ru electrode offers superior electrochemical performance with efficient electrolyte ion mobility for energy storage applications.
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Pullulan-based composite film can be a potential alternative packing material to non-environmentally friendly plastic wrap (PE) to preserve fresh-cut carrots. However, many developed pullulan-based composites either have high water vapor permeability (WVP) and high mechanical strength or vice versa, which limits the practicality of the developed packaging materials for potential commercialization. Herein, Abelmoschus manihot gum (AMG)/pullulan/magnesium L-ascorbate (MLA) was created as a green composite film (APL) to preserve fresh-cut carrots. The optimal amount of MLA was found to be 10 % (APL10), demonstrating a balance of lower WVP and greater mechanical strength and antioxidant performance than many pullulan-based films. This effectively solved many problems faced by other pullulan-based packaging films. After the fresh-cut carrots were packed with the composite film for 4 days, it was found that APL10 was effective in preserving the quality of carrots, in terms of freshness, weight loss rate, Vitamin C (VC), and malondialdehyde (MDA) content after 4 days of storage, much better than non-biodegradable PE. Thus, based on these findings, it is concluded that APL films have huge potential as a green packaging material for food to replace PE in the future.
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Metal-ion-dependent nucleases play crucial roles in cellular defense and biotechnological applications. Time-resolved crystallography has resolved catalytic details of metal-ion-dependent DNA hydrolysis and synthesis, uncovering the essential roles of multiple metal ions during catalysis. The histidine-metal (His-Me) superfamily nucleases are renowned for binding one divalent metal ion and requiring a conserved histidine to promote catalysis. Many His-Me family nucleases, including homing endonucleases and Cas9 nuclease, have been adapted for biotechnological and biomedical applications. However, it remains unclear how the single metal ion in His-Me nucleases, together with the histidine, promotes water deprotonation, nucleophilic attack, and phosphodiester bond breakage. By observing DNA hydrolysis in crystallo with His-Me I-PpoI nuclease as a model system, we proved that only one divalent metal ion is required during its catalysis. Moreover, we uncovered several possible deprotonation pathways for the nucleophilic water. Interestingly, binding of the single metal ion and water deprotonation are concerted during catalysis. Our results reveal catalytic details of His-Me nucleases, which is distinct from multi-metal-ion-dependent DNA polymerases and nucleases.
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ADN , Histidina , Histidina/metabolismo , Histidina/química , ADN/metabolismo , ADN/química , Cristalografía por Rayos X , Catálisis , Metales/metabolismo , Metales/química , Hidrólisis , Cationes Bivalentes/metabolismo , Modelos MolecularesRESUMEN
Background: Considerable morbidity and death are associated with acute kidney damage (AKI) following total aortic arch replacement (TAAR). The relationship between AKI following TAAR and serum magnesium levels remains unknown. The intention of this research was to access the predictive value of serum magnesium levels on admission to the Cardiovascular Surgical Intensive Care Unit (CSICU) for AKI in patients receiving TAAR. Methods: From May 2018 to January 2020, a prospective, observational study was performed in the Guangdong Provincial People's Hospital CSICU. Patients accepting TAAR admitted to the CSICU were studied. The Kidney Disease: Improving Global Outcomes (KDIGO) definition of serum creatinine was used to define AKI, and KDIGO stages two or three were used to characterize severe AKI. Multivariable logistic regression and area under the curve receiver-operator characteristic curve (AUC-ROC) analysis were conducted to assess the predictive capability of the serum magnesium for AKI detection. Finally, the prediction model for AKI was established and internally validated. Results: Of the 396 enrolled patients, AKI occurred in 315 (79.5%) patients, including 154 (38.8%) patients with severe AKI. Serum magnesium levels were independently related to the postoperative AKI and severe AKI (both, P < 0.001), and AUC-ROCs for predicting AKI and severe AKI were 0.707 and 0.695, respectively. Across increasing quartiles of serum magnesium, the multivariable-adjusted odds ratios (95% confidence intervals) of postoperative AKI were 1.00 (reference), 1.04 (0.50-2.82), 1.20 (0.56-2.56), and 6.19 (2.02-23.91) (P for Trend < 0.001). When serum magnesium was included to a baseline model with established risk factors, AUC-ROC (0.833 vs 0.808, P = 0.050), reclassification (P < 0.001), and discrimination (P = 0.002) were further improved. Conclusions: Serum magnesium levels on admission are an independent predictor of AKI. In TAAR patients, elevated serum magnesium levels were linked to an increased risk of AKI. In addition, the established risk factor model for AKI can be considerably improved by the addition of serum magnesium in TAAR patients hospitalized in the CSICU.