Search Results (451)

Oxidative catalytic fractionation (OCF) under the lignin-first strategy has emerged as a critical technological approach for biomass refining. To address the inevitable carbohydrate degradation and lignin condensation in conventional OCF, this study designed a cobalt-doped layered double hydroxide oxide (Co-LDO) catalyst compatible with non-alkaline (without Brønsted bases) organic systems, which exhibits excellent performance in poplar biomass OCF. With a straightforward preparation process, the Co-LDO catalyst yields high-content oxidized lignin oligomers while efficiently retaining carbohydrates, providing feedstock rich in carbohydrates (cellulose and hemicellulose) for the subsequent production of bioenergy and biomass-based chemicals. Under optimized conditions screened via systematic reaction condition investigation and metal-doped LDO catalyst evaluation, the process achieved a 94.01 wt% delignification rate, with 72.19 wt% of lignin converted into lignin oligomer oil, supported by detailed product composition and structural characterization. Meanwhile, 74.14 wt% hemicellulose and 98.23 wt% cellulose were recovered in solid residues, with structurally intact hemicellulose retention being 2.3 times higher than in traditional OCF. Mass balance calculation confirmed a total poplar refining yield of 81.58 wt%. In summary, this Co-LDO-catalyzed OCF strategy provides a high-activity non-precious metal system, effectively suppressing lignin condensation while preserving high-yield carbohydrates, realizing the efficient full-component refining of poplar biomass. Full article

The reaction mechanism of the gold-catalyzed hydrothiolation of alkenes (1) with thiols (2) has been investigated in detail. The tetranuclear gold complex, (PPh₃)₄Au₄(SPh)₂(NTf)₂ (A), is a key intermediate in the catalytic hydrothiolation of alkenes. It forms instantaneously when PPh₃AuNTf₂ and PhSH are mixed in THF. Monitoring the reaction over time using ³¹P NMR spectroscopy revealed that gold complex A remained stable in the reaction system throughout the hydrothiolation process. In addition, we successfully observed a rapid ligand-exchange reaction between the thiolate group of gold complex A and thiols in solution. The gold-catalyzed alkene hydrothiolation reaction has been applied to the catalytic hydrothiolation of allenes, which have degenerate double bonds. Hydrothiolation of allenes proceeded regioselectively at the terminal double bond. However, the yield was lower than that observed for alkenes, and catalyst deactivation occurred. The hydrothiolation products of allenes were difficult to detach from the gold catalyst, necessitating an increase in the reaction temperature. Since high periodic transition metals such as gold and platinum are effective for hydrothiolation of alkenes and allenes, it is interesting to clarify whether iridium complexes, which belong to the same period as gold and platinum, could also catalyze alkene hydrothiolation. Through a detailed investigation of iridium ligands and reaction conditions, it was found that, in iridium systems, disulfide formation via oxidative coupling of thiols occurs preferentially over hydrothiolation reactions. This is likely due to steric hindrance around the iridium center, which inhibits alkene coordination to the iridium. Additionally, the hydrothiolation proceeding at low yields is believed to be a radical reaction involving electron transfer through the iridium complex. Full article

Background/Objectives: This study aimed to evaluate the effects of short-term broccoli powder supplementation on metabolically demanding exercise performance, muscle power, and blood lactate recovery. It also investigated broccoli powder-derived sulforaphane bioavailability and its effects in attenuating exercise-induced oxidative stress. Methods: Seventeen healthy males (age 23.8 ± 4.9 years, height 182.3 ± 6.1 cm, weight 80.0 ± 12.8 kg), in a double-blind crossover design, three weeks apart, consumed ten standard doses of either broccoli powder or spinach powder as a placebo over a period of 2 weeks. They then performed a maximal progressive cycling task with concomitant analysis of expired gas composition. Plasma malondialdehyde (MDA) level was measured before and 60 min after the completion of the task, and blood lactate and muscle power (counter-movement vertical jump (CMJ) performance) were measured before and up to 60 min after exercise. Results: The main findings were that despite urine sulforaphane output being markedly higher following broccoli supplementation (p < 0.05), which confirms effective absorption and systemic availability of the compound, this did not influence exercise-induced changes in plasma MDA concentration, blood lactate dynamics, exercise test performance, or functional recovery measured as muscle power via CMJ performance (p > 0.05). Conclusions: In conclusion, broccoli powder supplementation, despite efficient delivery of sulforaphane, does not seem to either acutely affect performance or modify oxidative stress and recovery from metabolically demanding exercise. Full article

Magnetic nanoparticles represent the next-generation drug delivery systems, enabling drug targeting to specific organs without adverse effects on the body and with a controlled release rate. Their strengths are represented by biocompatibility, low cost, and easy drug loading; some drawbacks are aggregation and poor stability in biological media. In the present work, we synthesized magnetic core–shell structures with a magnetite core coated with layered double hydroxides (LDHs) based on Mg²⁺ or Zn²⁺ and Al³⁺ ions and loaded with meloxicam, a poorly water-soluble anti-inflammatory drug. Several syntheses have been attempted to obtain iron oxides based on the only magnetite phase. The combined use of different characterization techniques allowed us to reveal that the best product, showing the crucial room temperature superparamagnetism and a good level of compositional uniformity, was obtained from co-precipitation in nitrogen flow. The next LDH coating was successful, even if the hybrids showed the occurrence of aggregation. The drug was mainly adsorbed onto the LDH surfaces, as shown by the X-ray diffraction and Infrared Spectroscopy techniques. The loaded meloxicam amount was low, but the subsequent release into simulated body fluid could be prolonged for 4 days. Our study provides a proof of concept about the importance of a thorough characterization of the nanocomposite hybrids and their possible use for tricky drugs, such as those of class II of the Biopharmaceutical Classification System. Full article

Preeclampsia is a double-hit vascular disorder centred on the VEGF-HO-1-CSE axis. First, excess placental soluble Flt-1 (sFlt-1) neutralises vascular endothelial growth factor (VEGF) and placental growth factor (PlGF), producing an angiogenic deficit that drives endothelial dysfunction, hypertension, proteinuria and end organ injury. Second, the failure of endogenous vascular brakes, heme oxygenase-1 (HO-1/CO) and cystathionine-γ-lyase (CSE)/hydrogen sulfide (H₂S) removes physiological restraint on anti-angiogenic factor release (sFlt-1; soluble endoglin) and amplifies oxidative–inflammatory stress, lowering the threshold at which VEGF loss precipitates severe disease. We synthesise human, animal and translational data that (i) establish placental sFlt-1 source and release, (ii) demonstrate human mechanistic causality via sFlt-1 removal, (iii) show prospective clinical validation that sFlt-1 rises and free PlGF falls before disease onset, and (iv) identify HO-1 and CSE/H₂S as protective pathways that restrain anti-angiogenic drive. Finally, we summarise preclinical evidence that the orally administered H₂S-donor prodrug MZe786 restores the HO-1/CSE axis, lowers sFlt-1 and soluble endoglin (sEng), and improves maternal haemodynamics and foetal outcomes across complementary pregnancy models, and we outline the role of sFlt-1/PlGF and M-PREG-based triage in clinical decision making. While valuable for short-term triage, current sFlt-1/PlGF-based approaches cannot sub-stratify among positive cases. Framing severe preeclampsia as a double-hit vascular disorder provides a biologically grounded framework that can inform risk stratification strategies like M-PREG^®, a clinical decision support system informed by the double hit framework, and prevention strategies, pairing early risk stratification with mechanism-informed interventions. Full article

Landfill leachate, a byproduct of municipal solid waste treatment, typically contains hazardous substances such as toxic metals (e.g., lead) and eutrophication agents (e.g., phosphate). This study addresses the pressing challenge of polishing complex wastewater, such as landfill leachate, through the development of a novel ternary layered double hydroxide (LDH). As CaFe-LDHs are known to have an affinity for anions, and CoFe-LDHs have shown an affinity for toxic metal cations, CoCaFe-LDH was proposed to integrate both functionalities. The LDH was anchored on activated biochar to synthetize the novel composite adsorbent CoCaFe-LAB. Key operational parameters (including initial pH, adsorbent dosage, contact time, initial adsorbate concentration, presence of coexisting ions, and regeneration capability) were systematically evaluated. Kinetic and equilibrium analyses revealed that Elovich and Sips models, respectively, best described the adsorption behavior of Pb²⁺ and PO₄³⁻, indicating a heterogeneous adsorption system. Maximum adsorption capacities in synthetic solutions reached 140.81 mg Pb²⁺ g⁻¹ and 25.19 mg PO₄³⁻ g⁻¹ at 45 °C. The CoCaFe-LAB composite proved highly effective, particularly for lead removal. In real effluent tests, the adsorbent achieved complete phosphate removal (100%) from electro-oxidized landfill leachate at a dosage of 2.0 g L⁻¹, confirming its practical applicability and efficiency. Full article

Glutathione (GSH), often referred to as the “master antioxidant,” plays a vital role in protecting cells against oxidative stress. This human pilot study aimed to evaluate the oral absorption and safety profile of a novel formulation of micellar glutathione (LipoMicel^®, LMG) compared with two commonly used dietary supplement forms: standard glutathione (STD) and liposomal glutathione (Setria^® Glutathione, LSG). In the first phase, a randomized, double-blind, crossover study was conducted in healthy adults (n = 14) to assess whole-blood GSH following single oral doses using baseline-adjusted pharmacokinetic parameters (incremental AUC_0–24 [iAUC_0–24], C_max, T_max) and a targeted panel of glutathione-related metabolites. In the second phase, a 30-day, single-arm follow-up assessed the safety and tolerability of the most bioavailable formulation (LMG) in the same participants. Compared with STD (500 mg), LMG (300 mg) produced significantly higher baseline-adjusted systemic GSH exposure and peak response (iAUC_0–24: 1287.5 ± 179.0 vs. 517.8 ± 180.0 µg·mL·h; p = 0.0064; ΔC_max: 103.9 ± 11.8 vs. 42.8 ± 11.5 µg/mL; p = 0.0003), corresponding to ~2.49-fold higher incremental exposure and ~2.43-fold higher peak response at the administered doses. When dose-normalized to a 300 mg equivalent, the incremental exposure (iAUC) and C_max were up to 4-fold higher for LMG than STD. In the targeted metabolite panel, most analytes showed no formulation-dependent differences; however, dose-normalized methionine exposure was significantly higher with LMG than STD (iAUC: 149.9 ± 30.8 vs. 32.7 ± 28.3 µg·mL·h; p = 0.0151; ~4.58-fold). No significant differences were observed in oxidized glutathione (GSSG) exposure, while the GSH/GSSG ratio was higher following LMG versus STD (p = 0.001). No significant changes in clinical safety markers (e.g., ALT, AST, ALP, creatinine) were observed following 30 days of daily LMG administration at 600 mg/d. The novel micellar glutathione formulation demonstrated enhanced oral bioavailability compared with a standard glutathione preparation and was well tolerated over 30 days in healthy adults. These findings present LipoMicel^® as a promising approach for oral glutathione delivery and warrant further investigation into its long-term physiological and clinical effects. This clinical trial was registered at ClinicalTrials.gov under trial ID NCT06345950 on 3 April 2024. Full article

This study examines the impact of photovoltaic (PV) modeling fidelity utilizing single-diode (SDM), double-diode (DDM), and triple-diode (TDM) representations on the precision of hydrogen production (H₂P) estimates when integrated with various electrolyzer technologies, specifically proton exchange membrane (PEM), alkaline (AEL), and solid oxide electrolysis cells (SOECs). Precise evaluation of solar-powered green hydrogen (H₂) systems necessitated a dependable estimate of PV power under authentic working circumstances. Hourly site-specific irradiance and ambient temperature (T_a) data for Riyadh, Saudi Arabia, were used to calculate PV power outputs, which were then sent to physically based electrolyzer models regulated by electrochemical voltage relationships and Faraday’s law. The findings indicate that while all PV models display the same seasonal patterns, SDM somewhat overestimates yearly PV energy in comparison to DDM and TDM, with relative errors around 0.03%. These discrepancies somewhat affect H₂ yield estimations but do not change the relative ranking of electrolyzer technology. Among the assessed options, SOEC consistently produced the highest H₂ output, generating approximately 21.8% more H₂ than PEM and 9.1% more than AEL, with annual yields of 62.46–62.47 g for PEM, 69.70–69.71 g for AEL, and 76.04–76.05 g for SOEC across the SDM, DDM, and TDM frameworks under equivalent solar power inputs. The findings indicate that the selection of electrolyzer technology significantly impacts H₂P more than the choice of a PV model, while high-fidelity PV modeling is crucial for a physically realistic and precise system-level assessment of integrated PV-H₂ energy systems. Full article

In laboratory installations, wastewater from the distillery industry (ethanol stillage and vinasse) is treated via a two-stage combination of microbial sulfate reduction (MSR) and biomethanation, assisted by bioelectrochemical systems (BESs). In the first stage, a sulfidogenic bioreactor with an integrated microbial fuel cell (MFC) is used, which partially oxidizes the produced H₂S and facilitates the conversion of organic compounds. Sulfate removal reaches 95.4% (stillage) and 92.8% (vinasse), with corresponding COD reductions of 30.6% and 36.5%, respectively. The polarization curves, power density, generated current, and coulombic efficiency are analyzed. The sulfidogenic bioreactor consortium is dominated by Deltaproteobacteria, which contributes to acetate accumulation during the MSR stage. Methanogens are dominated by the genus Methanofolis. In the second stage of anaerobic digestion, three treatment options are investigated: direct biomethanation, biomethanation after preliminary MSR, and biomethanation after MSR with a microbial electrolysis cell (AD-MEC). The highest COD conversion rates are achieved in the AD-MEC variants: 91.36% for ethanol stillage and 92.8% for vinasse. Microbial communities are dominated by acetoclastic methanogens of the genus Methanothrix. For stillage treated after MSR, biogas production is nearly double that from direct methanation. For vinasse, the largest amount of biogas is generated during by the integrated MEC system, followed direct methanation. Methane content is the highest in methanation after MSR in AD-MEC (93.4–93.6%). Full article

Novel porous geopolymer (IGP&SS), possessing mesoporous structure and a compressive strength of 9.40 MPa, was synthesized through alkali activation of double solid wastes such as iron tailings and steel slag. To overcome the high activation energy barrier of oxidants for refractory pollutant treatment, the IGP&SS was designed to efficiently activate peroxymonosulfate (PMS) under visible-light irradiation, generating reactive radicals for the rapid degradation of methylene blue (MB). The system achieved nearly complete removal within 30 min. To enhance MB removal, the effects of key factors including IGP&SS dosage, PMS dosage, initial MB concentration, temperature, and pH on the degradation process were systematically investigated. Quenching experiments revealed that several reactive oxygen species contributed to MB degradation, with the order of contribution being •OH > ¹O₂ > SO₄•⁻ > •O₂⁻. Mechanistic studies indicated that the efficient MB degradation was primarily attributed to the flexible Fe(II)/Fe(III) redox cycling in IGP&SS, which accelerated PMS activation and radical generation. X-ray photoelectron spectroscopy (XPS) analysis of the post-reaction catalyst confirmed its structural robustness, revealing a characteristic binding energy shift in the O 1s peak to 530.8 eV and a quantitative redistribution of iron species (Fe(III) content increasing from 40.4% to 57.0%). Given its outstanding performance, demonstrated stability, and eco-friendly preparation, IGP&SS holds great promise for PMS-based advanced oxidation processes in dye wastewater treatment, offering a sustainable approach for high-value utilization of iron tailings and steel slag while alleviating resource scarcity. Full article

Ammonium dinitramide (ADN), a new-generation green high-energy oxidizer, faces application challenges due to its strong hygroscopicity and poor compatibility with polymer binders. This study proposes a double-shell structure with ADN as the core, graphene oxide (GO) as the intermediate layer, and a binder as the outer shell. Molecular dynamics simulations were performed to investigate composite systems using nitrocellulose (NC), cellulose acetate butyrate (CAB), polystyrene (PS), and their blends NC/CAB and NC/PS as binders. The results demonstrate that GO acts as a “molecular double-sided adhesive”, significantly enhancing the interfacial interaction between ADN and the binders. The NC/PS blend binder exhibits the best overall performance, with the binding energy increased by 1.13 times. Analysis revealed that the NC/PS system establishes the strongest intermolecular interactions among ADN, GO, and the binder via mechanisms like π-π stacking and multiple hydrogen bonds. The glass transition temperature reaches 400.93 K, indicating excellent thermal stability and potential safety/reliability. Mechanical property analysis shows that the NC/PS composite system imparts a better comprehensive balance of stiffness, shear performance, and structural isotropy to the ADN-based polymer-bonded explosive (PBX). This research elucidates the enhancement mechanism of GO and the regulation principles of binders at the molecular scale, providing a theoretical foundation for designing high-performance energetic material. Full article

Heart failure (HF) is a global health challenge characterized by the heart’s inability to satisfy metabolic demands, driven by renin–angiotensin–aldosterone system (RAAS) overactivation, a neurohormonal imbalance, and emerging mechanisms like the gut–heart axis and mitochondrial dysfunction. Affecting over 6 million adults in the US alone, HF incurs a 5-year mortality rate of 50% and escalating costs projected to double by 2030. This review examines HF’s molecular paradigms, integrating established pathways with advances in omics, stem cell therapy, genetic modification, and personalized medicine. The RAAS blockade remains central, yet its efficacy is limited in HF with preserved ejection fraction (HFpEF). Stem cell therapies (mesenchymal and induced pluripotent stem cells) show regenerative potential but face poor retention (<10% survival at 30 days). CRISPR/Cas9 offers precision, though off-target effects persist. The gut microbiome, via trimethylamine N-oxide, exacerbates inflammation, while omics technologies promise biomarkers for tailored treatments. Challenges include translating these innovations into practice, particularly for HFpEF. Future directions involve novel HFpEF therapies, enhanced stem cell delivery, precise genetic tools, and microbiome interventions, supported with artificial intelligence. By 2030, these advances could shift HF management toward regeneration, contingent on overcoming translational barriers through global collaboration. Full article

Nitrous oxide (N₂O) emissions in cereal-based rotations often show short-lived peaks after fertilization, but their contribution to annual budgets and their responsiveness to straw management remain poorly quantified. We combined a 13-year legacy fertilization experiment with two years of high-frequency N₂O monitoring in a rice–wheat rotation in central China to quantify post-fertilization peak windows and test how straw-return rate modulates these windows and annual emissions. Five long-term treatments were compared: an unfertilized control (CK), straw only (2M, 12 t ha⁻¹ yr⁻¹), mineral fertilizer (NPK), and NPK with 6 or 12 t ha⁻¹ yr⁻¹ straw (MNPK and 2MNPK). Under N input, wheat-season emissions dominated annual totals, with the ratio of wheat-season to annual N₂O emissions (WN/TN, where WN denotes wheat-season N₂O emissions and TN denotes annual cumulative N₂O emissions) of ~73–75% for NPK and MNPK, significantly higher than in CK and the straw-only control. Decomposition of annual fluxes showed that 56.6–65.4% of N₂O in N-applied treatments occurred within short windows after the two wheat-season fertilizations, whereas rice-season peaks were small and largely insensitive to treatment. Planned contrasts expressed as geometric mean ratios (GMRs) with 95% confidence intervals (CIs) highlighted a strong management leverage point: increasing straw from 6 to 12 t ha⁻¹ yr⁻¹ with NPK reduced annual and wheat-season N₂O by ~47% and 58%, respectively, primarily by lowering peak magnitude and shortening peak duration. Microbial analyses suggested that treatment effects on N₂O were better reflected by community compositional shifts (β-diversity) than by α-diversity, while amoA abundance showed guild-specific responses. Collectively, this study provides an event-window quantification framework that links high-frequency field measurements to a specific, actionable mitigation lever (straw-return rate) in rice–wheat systems. Together, these results identify wheat-season post-fertilization windows as the main control points for annual N₂O in rice–wheat rotations and show that pairing NPK fertilization with higher straw return can temper short-lived peaks. By explicitly pinpointing when (which windows) and how (attenuating peak magnitude and duration) mitigation is achieved, our findings offer a management-ready and transferable basis for targeted N₂O abatement in double-cropping systems. Full article

Objectives: The objective of this study was to evaluate the effect of 21-day dietary omega-3 fatty acid supplementation on the levels of postexercise inflammation response, oxidative stress, and selected exerkine secretion among physically active young men. Methods: In a randomized double-blind study, 24 physically active men were assigned to two groups: a supplementation group (n = 12), receiving 3250 mg of n-3 polyunsaturated fatty acids (PUFAs) daily, and a placebo group (n = 12). Blood samples were collected before and after twenty-one days of dietary supplementation to measure total fatty acids and inflammatory markers, including IL-1β, IL-6, IL-10, BDNF, and FGF23. Results: After 21 days of n-3 fatty acid supplementation, there were no significant changes in anaerobic performance parameters. However, significant interactions were found in the systemic immune-inflammation index (SII), FGF-23, IL-1β, IL-1Ra, IL-6, and IL-10 in response to exercise and supplementation. Conclusions: 21 days of n-3 fatty acid supplementation modified PUFA content and influenced inflammation status, but did not affect maximal anaerobic performance. Full article

Background: Hemodialysis (HD) patients frequently develop muscle wasting and chronic inflammation, conditions associated with functional decline and reduced quality of life (QoL). Nutritional strategies that provide targeted anabolic support without increasing nitrogen load may offer clinical benefits. The aim of this study was to evaluate the possible impact of a food for special medical purposes (FFSMP), composed of free-form branched-chain amino acids, β-hydroxy-β-methylbutyrate, and zinc, on muscle mass and strength, laboratory parameters, physical performance (PP), and QoL in HD patients. Methods: in this randomized double-blind crossover study, 24 adult HD patients received the FFSMP (10 g/day; two sachets) supplementation or placebo for 12 weeks, separated by an 8-week wash-out (protocol code RS 29.23). Measured outcomes included quadriceps rectus femoris thickness (QRFT) muscle, body composition analysis, inflammatory markers, oxidative stress indices, other routine biochemical parameters, PP, and QoL (SF-36 questionnaire). Results: FFSMP supplementation resulted in significant increases in QRFT and in fat-free mass percentage. Reductions in oxidative stress and inflammatory biomarkers were observed. Routine biochemical parameters remained stable, with the exception of a decrease in pre-dialysis urea. Functional performance measures did not differ between treatment periods. Improvements were noted in selected SF-36 domains, specifically energy/fatigue and general health. No major adverse events occurred during the study. Conclusions: In HD patients, this FFSMP produced favorable changes in markers of muscle mass and systemic inflammation without affecting short-term physical performance. These findings support the potential clinical utility of targeted amino acid supplementation in this patient population, highlighting the need for larger, longer-term trials. Full article