Search Results (700)

This study aimed to evaluate the incorporation of graphene-based additives, graphene nanoplatelets (GNPs) and graphene oxide quantum dots (GOQDs), into polymeric fiber matrices used as biofilm supports in anaerobic digestion systems, determining additive specific effects by benchmarking the impregnated matrices against the same nylon carrier without additives under identical operational conditions. Modified matrices were assessed through BMP assays using the liquid fraction of fruit and vegetable waste (LF-FVW) as substrate. Intermediate GNP and GOQD loadings (FM50 and FMDOT50) achieved the highest methane yields (317.9 ± 20.2 and 348.4 ± 20.0 mL CH₄/g COD_(rem)) compared with the control fiber matrix (301.0 ± 20.1 mL CH₄/g COD_(rem)). Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) analyses confirmed nanomaterial retention on the matrix surface and interaction with microbial aggregates. Embedding the nanostructures within the fiber enhanced biofilm formation and methane yield while minimizing nanomaterial washout. Future work will focus on advanced physicochemical characterization (XRD, XPS, BET, and EDX mapping), leaching tests to assess long term stability, and scale up evaluation for full scale anaerobic digestion applications. Full article

The chemical profile of coffee depends on numerous factors, the complexity of which makes it difficult to clearly assess their influence. The aim of this study was to comprehensively evaluate the impact of selected coffee brewing methods (Espresso, Simple Infusion, French Press, V60), taking into account the coffee species (Arabica, Robusta, Blends), the degree of roasting (light, medium, dark) and the geographical origin (single-origin and multi-origin) on the chemical composition of the brew. Eighteen different types of coffee, which differ in the aforementioned characteristics, were analyzed. The caffeine content (using high-performance liquid chromatography), the total phenolic content (TPC; using a spectrophotometric method), and selected minerals (calcium, iron, potassium, magnesium, sodium, phosphorus, zinc; using Inductively Coupled Plasma–Optical Emission Spectrometry) were analyzed. The analysis showed that both the brewing method and the species had a significant influence on the chemical profile of the resulting brews, while the degree of roasting and the origin showed no significant influence. The Espresso method showed the highest caffeine, TPC, potassium, magnesium, and phosphorus content, the V60 method—calcium, iron, and sodium, and the French Press and Simple Infusion methods showed intermediate values. Robusta coffee contained more caffeine and TPC, Arabica contained more magnesium, and Blend showed medium values for both species. The results obtained may have practical implications for both consumers and the coffee industry, supporting informed decision-making and the refinement of brewing methods. Full article

CO₂ hydrogenation to methanol has attracted considerable attention as a promising catalytic route for both reducing CO₂ emissions and producing valuable chemical intermediates. Among various catalysts, Cu–ZnO-based systems are the most widely studied; however, their performance remains constrained by limited methanol selectivity and stability, highlighting the need for improved catalytic strategies. In this work, liquid metal gallium (Ga) was incorporated into Cu–ZnO catalysts as an additive for CO₂ hydrogenation to methanol. Owing to its high dispersibility and fluidity, Ga helps maintain long-term catalyst stability. We investigated different introduction methods for Ga promoters and found that the physical mixing approach generated the strongest alkaline sites, thereby enhancing CO₂ activation and increasing the CO₂ conversion to methanol. Moreover, this catalyst effectively suppressed carbon deposition, further improving its stability. These findings offer new insights into the use of liquid metal Ga in CO₂ hydrogenation and provide fresh perspectives for the rational design of efficient methanol synthesis catalysts. Full article

Skarn-type iron ore is economically significant, and numerous skarn ore deposits have been identified in the North China Craton. The newly discovered orbicular diorite in this region is distinguished from other analogous rocks due to the accumulation of large magnetite particles, which may shed new light on the genesis of this ore type. The magnetite in different parts of the orbicular structure exhibits distinct compositional differences. For example, magnetite at the edge has a small particle size (200 μm) and is associated with the minerals plagioclase and hornblende, indicating that it crystallized from normal diorite magma. By contrast, magnetite in the core has a relatively large particle size (>1000 μm), is associated with apatite and actinolite, and contains apatite inclusions as well as numerous pores. The size of magnetite in the mantle falls between that of the edge and the core. The syngenetic minerals of magnetite in the mantle include epidote and plagioclase. The magnetites in the cores of orbicules have a higher content of Ti, Al, Ni, Cr, Sc, Zn, Co, Ga, and Nb than those in the rim. The δ⁵⁶Fe value of the core magnetite (0.46‰–0.78‰) is much higher than that of the mantle and rim magnetite in orbicules. Moreover, the δ⁵⁶Fe value of magnetite increases as the V content of magnetite gradually decreases. This large iron isotope fractionation is likely driven by liquid immiscibility that forms iron-rich melts under high oxygen fugacity. The reaction between magma and carbonate xenoliths (Ca, Mg)CO₃ during magma migration generates abundant CO₂, which significantly increases the oxygen fugacity of the magmatic system. Under the action of CO₂ and other volatile components, liquid immiscibility occurs in the magma chamber, and Fe-rich oxide melts are formed by the melting of carbonate xenoliths. Iron oxides (Fe₃O₄/Fe₂O₃₎ will crystallize close to the liquidus due to high oxygen fugacity. These characteristics of magnetite in the Tanling orbicular diorite (Wuan, China) indicate that diorite magma reacts with carbonate xenoliths to form “Fe-rich melts”, and skarn iron deposits are probably formed by the reaction of intermediate-basic magma with carbonate rocks that generate such “Fe-rich melts”. A possible reaction is as follows: diorite magma + carbonate → (magnetite-actinolite-apatite) + garnet + epidote + feldspar + hornblende + CO₂↑. Full article

Pistachio (Pistacia vera L.) holds significant importance due to its diverse applications and nutritional benefits. The nuts are rich in essential amino acids, antioxidants, fiber, healthy fats, and minerals, making them highly valuable for human nutrition. However, pistachios are significantly challenged by salinity stress, which negatively affects their growth and metabolism. Understanding the impact of salinity stress on pistachios is crucial for developing effective strategies to enhance their tolerance, improve growth, and ensure sustainable production in saline environments. To investigate the effects of salinity on energy metabolism and amino acid composition, we monitored key metabolites and free amino acid levels in UCB-1 pistachio leaves at 7- and 21-day salt stress treatments using Liquid Chromatography–Mass Spectrometry (LC-MS) and Ultra Performance Liquid Chromatography (UPLC). Our findings revealed that salinity affected nearly all analyzed metabolites, with varied patterns observed at different time points. Notably, all free amino acids except threonine accumulated significantly in response to salt stress. Meanwhile, reductions in 3PGA, Fru1,6bP, and Glu6P+Fru6P (glycolysis and Calvin cycle intermediates) suggest a decrease in photosynthetic activity, which may ultimately impact respiration rates. These results demonstrate that salinity stress affects both amino acid metabolism and central carbon metabolism, with the magnitude and pattern of these changes depending on the duration of exposure. The observed metabolic adjustments likely represent an adaptive response, enabling the plant to partially mitigate the detrimental effects of salt stress. Full article

Alkaptonuria (AKU) is a rare metabolic disorder caused by homogentisate 1,2-dioxygenase (HGD) deficiency, leading to homogentisic acid (HGA) accumulation and ochronotic pigment deposition, which drug therapy cannot reverse. The process of pigment formation and deposition is still unclear. This study offers molecular insights into the polymeric structure, with the goal of developing future adjuvant strategies that can inhibit or reverse pigment formation, thereby complementing drug therapy in AKU. HGA polymerisation was examined under physiological, acidic, and alkaline conditions using liquid and solid phase nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR), and polyacrylamide gel electrophoresis. At physiological pH, HGA polymerised slowly, while alkaline catalysis accelerated pigment formation while retaining the HGA aromatic scaffold. During the process, EPR detected a semiquinone radical intermediate, consistent with an oxidative coupling mechanism. Reactivity profiling showed the diphenol ring was essential for polymerisation, while –CH₂COOH modifications did not impair reactivity. Pigments displayed a polydisperse molecular weight range (11–50 kDa) and a strong negative charge. Solid-state NMR has revealed the presence of phenolic ether and biphenyl linkages. Collectively, these identified structural motifs can serve as a foundation for future molecular targeting related to pigment formation. Full article

Elucidating amyloid formation inside biomolecular condensates requires models that resolve (i) local, chemistry specific contacts controlling β registry and (ii) mesoscale phase behavior and cluster coalescence on microsecond timescales—capabilities beyond single resolution models. We present a hybrid united atom/coarse grained (UA–CG) force field coupling a PACE UA peptide model with the MARTINI CG framework. Cross resolution nonbonded parameters are first optimized against all atom side chain potentials of mean force to balance the relative strength between different types of interactions and then refined through universal parameter scaling by matching radius of gyration distributions for specific systems using. We applied this approach to simulate a recently reported model system comprising the LVFFAR₉ peptide that can co-assemble into amyloid fibrils via liquid–liquid phase separation. Our ten-microsecond simulations reveal rapid droplet formation populated by micelle like nanostructures with its inner core composed of LVFF clusters. The nanostructures can further fuse but the fusion is reaction-limited due to an electrostatic coalescence barrier. β structures emerge once clusters exceed ~10 peptides, and the LVFFAR₉ fraction modulates amyloid polymorphism, reversing parallel versus antiparallel registry at lower LVFFAR₉. These detailed insights generated from long simulations highlight the promise of our hybrid UA–CG strategy in investigating the molecular mechanism of condensate aging. Full article

Advanced oxidation processes (AOPs) utilizing peroxymonosulfate (PMS) have recently gained attention for effectively removing organic dyes. Biochar, a carbon-based material, can act as a catalyst carrier for PMS activation. This study developed a nitrogen-doped biochar catalyst (NCMR800–2) from waste Chinese medicine residue (CMR) through one-step pyrolysis to efficiently remove Rhodamine B (RhB) from wastewater. Results indicate that NCMR800–2 rapidly achieved complete removal of 20 mg/L Rhodamine B (RhB), the primary focus of this study, within 30 min, while maintaining high degradation efficiencies for other pollutants and significantly outperforming the unmodified material. The material demonstrates strong resistance to ionic interference and operates effectively across a wide pH range. Quenching experiments and in situ testing identified singlet oxygen (¹O₂) as the primary active species in RhB degradation. Electrochemical analysis showed that nitrogen doping significantly enhanced the electrical conductivity and electron transfer efficiency of the catalyst, facilitating PMS decomposition and RhB degradation. Liquid chromatography–mass spectrometry (LC-MS) identified intermediate products in the RhB degradation process. Seed germination experiments and TEST toxicity software confirmed a significant reduction in the toxicity of degradation products. In conclusion, this study presents a cost-effective, efficient catalyst with promising applications for removing persistent organic dyes. Full article

Deoxynivalenol (DON) is one of the most common trichothecene mycotoxins found in cereals, posing a significant hazard to food and feed safety. Insects, especially the yellow mealworm (Tenebrio molitor), offer promising alternative protein sources; however, their capacity to metabolise mycotoxins and the nutritional implications are still not fully understood. In this study, T. molitor larvae were reared for two weeks on diets containing DON at 663 or 913 µg/kg, and their biomass was analysed using Liquid Chromatography–Quadrupole Time-of-Flight Mass Spectrometry (LC-QTOF) for DON metabolites and free amino acids, as well as Gas Chromatography–Flame Ionization Detector (GC-FID) for fatty acid profiles. Larvae metabolised DON via multiple pathways, including sulfonation, glucuronidation, sulfation, glucosylation, and de-epoxidation, with a time- and dose-dependent shift towards glucosylation and de-epoxidation. DON exposure significantly reduced the levels of essential amino acids such as methionine, lysine, phenylalanine, and isoleucine, and lowered metabolic intermediates like aspartic and glutamic acid. Conversely, prolonged DON exposure increased linoleic acid levels in larval fat, indicating altered lipid metabolism. These findings demonstrate that T. molitor larvae detoxify DON but incur measurable metabolic costs, leading to changes in amino acid and fatty acid profiles. The dual effect—reduction of toxin levels and nutritional shifts—highlights both the potential and the challenges of using insects for sustainable feed production. Full article

Background/Objectives: Trimethylamine N-oxide (TMAO), a gut microbiota-derived metabolite influenced by diet, has been linked to cardiovascular disease. Endothelial dysfunction, an early sign of vascular damage, is common in hypertension. This study examined the relationship between serum TMAO levels and endothelial function, assessed by the vascular reactivity index (VRI), in patients with hypertension. Methods: In total, 110 patients with hypertension were enrolled. Fasting serum TMAO was measured using high-performance liquid chromatography–mass spectrometry. Endothelial function was evaluated via digital thermal monitoring, with VRI categorized as good (>2.0), intermediate (1.0–1.9), or poor (<1.0). Results: Of the participants, 10 (9.1%) exhibited poor vascular reactivity, 57 (51.8%) had intermediate reactivity, and 43 (39.1%) exhibited good vascular reactivity. Poor reactivity correlated with older age (p = 0.010), higher total cholesterol (p = 0.007), low-density lipoprotein cholesterol (p = 0.009), and higher TMAO levels (p < 0.001). In multivariate forward stepwise linear regression, the log-transformed TMAO level (log-TMAO) remained independently and inversely associated with VRI (p < 0.001). Logistic regression analyses demonstrated that elevated TMAO concentrations were significantly associated with an increased likelihood of vascular reactivity dysfunction (intermediate and poor groups combined; odds ratio [OR] = 1.10, 95% confidence interval [CI]: 1.047–1.155; p < 0.001) and, in particular, with poor vascular reactivity (OR = 1.58, 95% CI: 1.002–2.492; p = 0.049). Conclusions: Elevated serum TMAO is independently associated with endothelial dysfunction in hypertension. Full article

End-stage kidney disease is preferably treated by kidney transplantation. The function of the allograft often determines kidney-controlled processes and requires long-term monitoring. Kidneys are organs with a very high metabolic rate, and, thus, a metabolomics approach is suitable to observe systemic metabolic changes that are related to graft adaptation. To understand these ongoing changes in post-transplant pediatric patients, we applied a targeted liquid chromatography/tandem mass spectrometry-based metabolomics approach. Time-dependent changes of 140 metabolites in plasma samples prospectively collected from 23 pediatric kidney graft recipients receiving tacrolimus-based immunosuppression were monitored over the first 4 years after transplantation and compared to levels prior to transplantation. Furthermore, by comparing the pre-transplant metabolite levels to those measured in healthy children, we were able to obtain insights into the pathways associated with kidney failure. Arginine biosynthesis, alanine, aspartate, glutamine, and glutamate metabolism, taurine and tryptophan metabolism were the most affected pathways that separate the pediatric patients with and without kidney failure. Accumulation of uremic toxins such as various tryptophan/kynurenine and tryptophan/indole metabolism pathway intermediates, and betaine and methionine cycle metabolites was evident in patients with restricted kidney function. Furthermore, reduced nicotinamide production, insufficient hydroxylation of phenylalanine to tyrosine, lowered cysteine, arginine, glutamine, taurine, and overall amino acid utilization, as well as diminished levels of protective antioxidants such as glutathione and vitamins B6 and C, were all the result of progressive kidney failure leading to transplantation. Importantly, following kidney transplantation and recovery of kidney function, the levels of most of the previously described metabolites normalized toward the levels observed in healthy participants. The here identified metabolic patterns could be used as markers to monitor the progression of pediatric chronic kidney disease patients towards kidney failure, and assuming their direct association with kidney function, they could serve as markers of successful graft adaptation. Full article

Introduction: Non-surgical biopsy is recommended for diagnosing solid pulmonary nodules measuring >8 mm when the probability of malignancy is low to moderate. However, currently available biopsy methods do not have a sufficient diagnostic yield for nodule size <20 mm. Previous work has shown that one-lung flooding (OLF) enables complete lung sonography and good demarcation of lung nodules. Therefore, here, we report the first experiences with ultrasound-guided transthoracic core needle biopsy (USgTTcNB) under OLF for the histological diagnosis of small pulmonary nodules. Methods: In two patients with small pulmonary nodules, a transbronchial/thoracic biopsy was not indicated due to the size and location of the nodules. Following nodule detection under OLF, the USgTTcNB was performed. The biopsy cylinder was immediately examined via the frozen section procedure. After liquid draining and re-ventilation, the patients were extubated in the operation room and monitored in the intermediate care unit. Results: In both patients, a histological diagnosis was achieved. In the case of malignancy, the patient underwent lobectomy during the same session. In the case of a benign diagnosis, a futile operation was avoided. In case two, a small apical pneumothorax occurred. The hemodynamic values during and after the intervention were in the normal range. Lung function on day 2 after the intervention increased compared with that before the intervention. Conclusions: USgTTcNB under OLF is feasible and enables a histological confirmation of small pulmonary nodules. Nevertheless, this new promising technique should be evaluated in a study with a larger cohort. Full article

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is caused by pathogenic mutations in the nuclear TYMP gene, which encodes the cytosolic enzyme thymidine phosphorylase. In addition to the systemic accumulation of thymidine and deoxyuridine, several case studies have reported abnormalities in a range of other metabolites in patients with MNGIE. Since metabolites are intermediates or end-products of numerous biochemical reactions, they serve as highly informative indicators of an organism’s metabolic activity. This study aimed to perform an untargeted metabolomic profiling to determine whether individuals with MNGIE exhibit a distinct plasma metabolic signature compared to 15 age- and sex-matched healthy controls. Metabolites were profiled using Ultra-High-Performance Liquid Chromatography–Mass Spectrometry (UHPLC-MS). A total of 160 metabolites were found to be significantly upregulated and 260 downregulated in patients with MNGIE. KEGG pathway enrichment analysis revealed disruptions in 20 metabolic pathways, with arachidonic acid metabolism and bile acid biosynthesis being the most significantly upregulated. Univariate receiver operating characteristic (ROC) curve analyses identified 23 individual metabolites with diagnostic potential, each showing an area under the curve (AUC) ≥ 0.80. We propose that an impaired resolution of inflammation contributes to a chronic inflammatory state in MNGIE, potentially driving disease progression. Additionally, we suggest that the gut–liver axis plays a central role in MNGIE pathophysiology, with hepatic function being bidirectionally influenced by gut-derived factors. Full article

Intermediate-temperature (IT) proton-exchange membranes (PEMs) play vital roles in hydrogen and direct liquid fuel cells, electrolyzers, and other electrochemical membrane reactors at elevated temperatures of higher than 150 °C. This article reports the fabrication and performance assessment of a type of new IT polymer–inorganic composite (PIC) PEMs that were made of cerium ultraphosphate (CeP₅O₁₄-CUP) as the durable solid-state proton conductor and undoped polybenzimidazole (PBI) as the high-temperature (HT) polymeric binder. The proton conductivity and electrochemical performance of the PIC PEMs were characterized at 200 °C with varying membrane thickness, processing parameters, and operating conditions using a single-stack hydrogen fuel cell connected to a fuel cell test station. Experimental results show that the PIC membranes (with CUP of 75 wt.%) carried high mechanical flexibility and strength as well as noticeably reduced water uptake of 4.4 wt.% compared to pristine PBI membranes of 14.0 wt.%. Single-stack hydrogen fuel cell tests at 200 °C in a humidified hydrogen and air environment showed that the proton conductivity of the PIC PEMs was measured up to 0.105 S/cm, and the electrochemical performance exhibited its dependence upon the membrane thickness with the power density of up to 191.7 mW/cm². Discussions are made to explore performance dependence and improvement strategies. The present study expects the promising future of the IT-PIC-PEMs for broad applications in high-efficiency electrochemical energy conversion and value-added chemical production at elevated temperatures of 200 °C or higher. Full article

Avocado is a unique fruit in which of seven-carbon (C7) sugars (notably D-mannoheptulose and perseitol) dominate the carbohydrate profile at harvest. Despite growing interest in sugar-mediated ripening processes, limited comparative data exist across cultivars. This work characterises the dynamic changes in non-structural carbohydrates in the mesotecarp of three commercially relevant avocado varieties—Bacon, Fuerte, and Hass—across four defined ripening stages, from unripe to overripe, with five biological replicates per stage. Using a validated hydrophilic interaction liquid chromatography–mass spectrometry (HILIC–MS) method, we quantified five key sugars and assessed their evolution through ripening. Concentrations varied among the studied samples within the following ranges: D-mannoheptulose, 0.4–49 mg/g dry weight (DW); perseitol, 0.5–23 mg/g DW; glucose, 0.8–5.3 mg/g DW; fructose, 0.6–4.5 mg/g DW; and sucrose, 0.5–3.4 mg/g DW. C7 sugar levels consistently declined, while C6 sugars increased—primarily between the intermediate and ready-to-eat stages—with distinct cultivar-specific patterns. Bacon maintained elevated C7 concentrations for a longer period; Fuerte exhibited a rapid transition from C7 to C6 sugars; and Hass displayed a more gradual and balanced shift. Multivariate analysis (partial least squares discriminant analysis, PLS-DA) effectively discriminated between cultivars at each ripening stage, confirming cultivar-specific metabolic signatures. These findings offer new insights into avocado carbohydrate metabolism, emphasising variety-dependent pathways that could inform breeding strategies, optimise postharvest ripening protocols, and support the nutritional characterisation of different avocado cultivars. Full article