Search Results (2,546)

One-dimensional ZnO nanowires offer significant potential for optoelectronic applications, though their controlled synthesis remains challenging. This study optimized ZnO nanowire growth via carbothermal reduction vapor transport based on the vapor–liquid–solid mechanism. Key parameters investigated were gold catalyst thickness and annealing, source temperature, system pressure, and oxygen concentration. Results show that thinner Au films promote high-density, small-diameter nanowires. An optimal source temperature window (950–1000 °C) was identified, while pressure and oxygen content critically influenced growth mode by modulating vapor supersaturation. Under optimized conditions, aligned single-crystalline ZnO nanowires with hexagonal wurtzite structure were achieved. Structural and optical characterization confirmed high crystallinity and strong near-band-edge emission, demonstrating the efficacy of the developed approach for tailored nanowire synthesis. Full article

Cannabinoids can bind to several cannabinoid receptors and modulate cellular signaling and gene expression relevant to inflammation and lipid homeostasis. Likewise, several vitamin E analogs can modulate inflammatory signaling and foam cell formation in macrophages by antioxidant and non-antioxidant mechanisms. We analyzed the regulatory effects on the expression of genes involved in cellular lipid homeostasis (e.g., CD36/FAT cluster of differentiation/fatty acid transporter and scavenger receptor SR-B1) and inflammation (e.g., inflammatory cytokines, TNFα, IL1β) by cannabinoids (cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC)) in human THP-1 macrophages with/without co-treatment with natural alpha-tocopherol (RRR-αT), natural RRR-αTA (αTAn), and synthetic racemic all-rac-αTA (αTAr). In general, αTAr inhibited both lipid accumulation and the inflammatory response (TNFα, IL6, IL1β) more efficiently compared to αTAn. Our results suggest that induction of CD36/FAT mRNA expression after treatment with THC can be prevented, albeit incompletely, by αTA (either αTAn or αTAr) or CBD. A similar response pattern was observed with genes involved in lipid efflux (ABCA1, less with SR-B1), suggesting an imbalance between uptake, metabolism, and efflux of lipids/αTA, increasing macrophage foam cell formation. THC increased reactive oxygen species (ROS), and co-treatment with αTAn or αTAr only partially prevented this. To study the mechanisms by which inflammatory and lipid-related genes are modulated, HEK293 cells overexpressing cannabinoid receptors (CB1 or TRPV-1) were transfected with luciferase reporter plasmids containing the human CD36 promoter or response elements for transcription factors involved in its regulation (e.g., LXR and NFκB). In cells overexpressing CB1, we observed activation of NFκB by THC that was inhibited by αTAr. Full article

Gut microbiota has emerged as a modulator of host metabolism and energy balance. However, the precise microbial metabolites mediating thermogenic activation in obesity remain largely undefined. We investigated the effect of antibiotic treatment under a high-fat diet on metabolites and its contribution to lipolysis and thermogenesis. Antibiotic treatment in high-fat diet-fed rats reduced adiposity and enhanced adaptive thermogenesis. Metabolomics revealed elevated taurine levels in the cecum content and plasma of antibiotic-treated animals, correlating with increased expressions of UCP1 and TGR5 in brown adipose tissue. Taurine enhanced lipolysis and oxygen consumption in mouse adipose tissue and human adipocytes. Thereby, taurine modulated lipolysis dependent on TGR5 signaling in adipose tissue. Human data confirmed that taurine promotes browning of white adipocytes and that acute cold exposure leads to a marked drop in circulating taurine, suggesting its rapid recruitment into thermogenic tissues. Besides its synthesis in the liver and dietary uptake, taurine can be a microbiota-derived metabolite that activates adipose thermogenesis and lipolysis through TGR5 and possibly taurine transporter-dependent mechanisms. These findings uncover a gut–adipose axis with therapeutic potential for metabolic disease. Full article

Nanoplastics (NPs) pose significant risks due to their small size and ability to penetrate biological tissues. However, the molecular pathways and cellular mechanisms affected by NP exposure in marine teleosts remain poorly understood, especially in tropical reef fishes. This study examined the impact of short-term (7 days) waterborne exposure of 100 nm-carboxyl-modified polystyrene NPs on the false clownfish (Amphiprion ocellaris) exposed at two daily concentrations: low (20 µg/L, environmentally relevant) and high (2000 µg/L). A multidisciplinary approach, including biochemical and transcriptomic analyses, was conducted to assess toxic effects. Biochemical assays revealed limited changes in antioxidant defenses (CAT, GR, GST, TOSC). However, the Integrated Biomarker Response index (IBRv2i) suggested a compromised physiological condition, supported by transcriptomic data. Transcriptomic profiling revealed 409 significantly differentially expressed genes (DEGs) in the high-concentration and 354 DEGs in the low-concentration groups, with 120 shared DEGs mostly upregulated and indicative of a core molecular response. Collectively, the transcriptional profile of the low-concentration group resembled an early-warning, energy-reallocation strategy aimed at preserving essential sensory functions while minimizing expendable functions. The high-concentration group amplified the shared stress signature and recruited an additional 289 unique genes, resulting in pronounced enrichment of Gene Ontology terms related to “muscle contraction”, “oxygen transport”, “hydrogen-peroxide catabolism”, and “extracellular-matrix”. This study demonstrates that PS-NP exposure can alter gene expression and physiology in juvenile reef fish, even at environmentally relevant concentrations. Molecular responses varied with concentrations highlighting the role of exposure level in influencing biological systems and potential long-term impacts of NP pollution in marine environments. Full article

The agricultural industry faces increasing environmental degradation due to the intensive use of conventional chemical fertilizers, leading to water pollution and alterations in soil composition. In addition, root-knot and cyst nematodes are major constraints to cucumber production, causing severe root damage and yield losses worldwide, underscoring the need for sustainable alternatives to conventional fertilization and pest management. Under greenhouse conditions, a four-month cultivation trial evaluated vegetable oil-, micronutrient-, and activated flavonoid-based biostimulants, applying Key Eco Oil^® (Miami, USA) via soil drench (every 15 days) combined with foliar sprays of CropBioLife^® (Victoria, Australia) and KeyPlex 120^® (Miami, USA) (every 7 days). Results showed reduced parasitic nematodes by 66% in soil and decreased gall formation by 41% in roots. Chlorophyll fluorescence and infrared gas analysis revealed higher oxygen-evolving complex efficiency (38%), increased PSII electron transport, improved the fluorescence decrease ratio, also known as the vitality index (Rfd), and higher CO₂ assimilation compared to conventional treatments. Processed cucumbers showed higher sugar and nearly double ascorbic acid content, with improved flesh consistency and color. Therefore, the application of these bioactive products significantly reduced nematode infestation while enhancing plant growth and physiological performance, underscoring their potential as sustainable tools for crop cultivation and protection. These results provide evidence that sustainable bioactive biostimulants improve plant resilience, productivity, and nutritional quality, offering also an environmentally sound approach to pest management. Full article

The establishment of a sustained human presence on the Moon is critically dependent on the ability to utilize local resources, primarily the production of oxygen for life support and propellant. The ROXY (Regolith to Oxygen and metals conversion) process is a molten salt electrolysis technology designed for this purpose. This paper presents an economic analysis of a ROXY pilot plant capable of producing over one ton of oxygen per year. We evaluate the economic viability by analyzing development, transportation, and operational costs against the potential revenue from selling oxygen and metals within a nascent lunar economy. A key aspect of this analysis is the perspective of an early customer in habitation life support systems preceding that of much higher propellant production demand. The analysis contextualizes this paradigm by recognizing that the primary economic driver for oxygen production is the larger future market for propellant; however, early life support demand may incentivize a paradigm-shift from Earth-based consumable resupply. Scenarios based on varying transportation costs and development timelines are evaluated to determine the internal rate of return (IRR) and time to break even (TTBE). The results indicate that the ROXY pilot plant is economically viable, particularly in near-term scenarios with higher transportation costs, achieving a positive IRR of up to 47.4% when both oxygen and metals are sold. The analysis identifies facility mass, driven by the robotics subsystem, as the primary factor for future cost-reduction efforts, concluding that ROXY is a technically and economically sound pathway toward sustainable lunar operations. Full article

Neurons have exceptionally high energy demands, sustained by thousands to millions of mitochondria per cell. Each mitochondrion depends on the integrity of its mitochondrial DNA (mtDNA), which encodes essential electron transport chain (ETC) subunits required for oxidative phosphorylation (OXPHOS). The continuous, high-level ATP production by OXPHOS generates reactive oxygen species (ROS) that pose a significant threat to the nearby mtDNA. To counter these insults, neurons rely on base excision repair (BER), the principal mechanism for removing oxidative and other small, non-bulky base lesions in nuclear and mtDNA. BER involves a coordinated enzymatic pathway that excises damaged bases and restores DNA integrity, helping maintain mitochondrial genome stability, which is vital for neuronal bioenergetics and survival. When mitochondrial BER is impaired, mtDNA becomes unstable, leading to ETC dysfunction and a self-perpetuating cycle of bioenergetic failure, elevated ROS levels, and continued mtDNA damage. Damaged mtDNA fragments can escape into the cytosol or extracellular space, where they act as damage-associated molecular patterns (DAMPs) that activate innate immune pathways and inflammasome complexes. Chronic activation of these pathways drives sustained neuroinflammation, exacerbating mitochondrial dysfunction and neuronal loss, and functionally links genome instability to innate immune signaling in neurodegenerative diseases. This review summarizes recent advancements in understanding how BER preserves mitochondrial genome stability, affects neuronal health when dysfunctional, and contributes to damage-driven neuroinflammation and neurodegenerative disease progression. We also explore emerging therapeutic strategies to enhance mtDNA repair, optimize its mitochondrial environment, and modulate neuroimmune pathways to counteract neurodegeneration. Full article

Nitrite pollution in aquatic environments, often driven by human activity, can disrupt fish physiology. Nitrite is absorbed by freshwater fish through their gills, leading to internal accumulation and interference with nitric oxide (NO) signaling, redox state, and the oxygen-carrying capacity of blood. The effects of nitrite are concentration-dependent. Although moderate environmental nitrite levels have little impact on oxygen transport, they may still interfere with NO homeostasis and cellular metabolism. We report the effects of 72 h of exposure to 10 μM nitrite on adult zebrafish blood’s O₂-carrying capacity and on muscle mitochondrial activity, metabolism, and redox state. The results show that this environmentally relevant but moderate concentration of nitrite leads to decreases in fish routine oxygen consumption (rMO₂) and spontaneous activity, an increase in blood nitrosyl hemoglobin (HbNO), indicating increased NO production in the blood, accumulation of nitrite in muscle tissue, oxidative stress, and changes in muscle aerobic capacity linked to a rise in mitochondrial efficiency. Parallel to these effects, increases in antioxidant capacity, arginase activity, and urea and lactate levels were observed. Globally, these results are consistent with altered NO homeostasis in the fish body induced by nitrite stress. Full article

Developing electrocatalysts that are efficient and durable for the oxygen evolution reaction (OER) is essential for improving the energy efficiency of alkaline water splitting. Spinel-type transition-metal oxides have emerged as promising non-noble alternatives; however, their catalytic performance is often limited by sluggish charge transport and insufficient utilization of active sites. Herein, we present a systematic comparative study of electrodeposited Co₃O₄ (CO-300) and Cu-substituted Co₂CuO₄ (CCO-300) nanosheet films directly grown on Ni foam. Structural, morphological, and spectroscopic analyses reveal that Cu²⁺ integration into Co-oxide spinel lattice modifies the local electronic environment and produces a more open and interconnected nanosheet architecture, thereby enhancing conductivity and increasing the density of accessible redox-active sites. As a result, the optimized CCO-300 exhibits superior catalytic performance at higher current densities, along with a smaller Tafel slope (44 mV dec^–1), a larger electrochemically active surface area (ECSA), and reduced charge-transfer resistance compared to CCO-300, indicating accelerated reaction kinetics and improved electron-ion transport. Furthermore, the multistep chronopotentiometry measurements and long-term stability tests over 100 h at current densities of 10 and 250 mA cm^–2 highlight the excellent operational stability of the CCO-300 catalyst. Full article

Heat threatens male fertility in crops, yet the regulatory basis of anther dehiscence under high temperatures remains unclear. We compared a heat-sensitive pepper cultivar (DL) with a heat-tolerant landrace (B021) across two anther stages using integrated transcriptome, small-RNA, degradome, co-expression, and enzymatic assays. DL showed a collapse of anther dehiscence above 34–38 °C, whereas B021 retained normal dehiscence at 39 °C, and histology revealed tapetal enlargement, premature degeneration, and locule contraction only in DL. RNA-seq indicated genotype- and stage-dependent reprogramming, with DL suppressing phenylpropanoid/cell-wall, transport, and proteostasis pathways, while B021 maintained reproductive and stress-integration programs. Small-RNA profiling and degradome sequencing identified conserved miRNA families with in vivo target cleavage, and notably, miR397 targeting a laccase gene showed stronger evidence in B021, which is consistent with controlled lignification. Functional organization of differentially expressed miRNA targets highlighted modules in respiration/redox, hormone and terpenoid metabolism, vascular–cell-wall programs, and proteostasis/osmotic buffering. WGCNA modules correlated with heat-tolerance traits converged on the same processes. Enzyme assays corroborated multi-omics predictions, with SOD, CAT, and POD activities consistently induced in B021 and limited MDA accumulation. Together, the data supports a model in which tolerant anthers sustain dehiscence under heat by coordinating secondary-wall formation, auxin/jasmonate/gibberellin crosstalk, respiratory and reactive oxygen species buffering, and protein/membrane quality control, providing tractable targets for breeding heat-resilient peppers. Full article

Our main goal was to determine whether the accumulation of Cd and Cu is harmful for L. perenne or whether this plant can be used in the bioremediation, e.g., of wastewaters or contaminated soils. The IC50 values (concentration at which the tested parameter is inhibited to 50% against the control) for root and shoot inhibition after 14 days showed that Cu, as an essential element for plants, was more toxic than Cd. The translocation factor (TF), which refers to metal transport from the root to the shoot, did not exceed values of 0.228 and 0.353 for Cd and Cu, respectively, indicating their accumulation mostly in the roots rather than in the shoots. The protein thiol (-SH) groups as a parameter of the increased level of reactive oxygen species did not confirm the significantly higher level of oxidative stress for Cu, which is a redox-active cation. We confirmed a statistically significant positive correlation between -SH groups and chlorophyll a (r = 0.79; p < 0.05) and chlorophyll b (r = 0.84; p < 0.01) in the presence of Cd. We concluded that bioaccumulation of the tested metals occurred mostly in the roots, and the photosynthetic pigment content in the shoots was not significantly impaired by the increased presence of Cd or Cu in the shoots. Therefore, we suggest L. perenne as a suitable candidate for the phytomining or phytoextraction of metals, mostly from wastewater, in cooperation with other plant hyperaccumulators. Full article

Advanced ceramics are known for their lightweight, high-temperature resistance, corrosion resistance, and biocompatibility. They are crucial in energy conversion, environmental protection, and aerospace fields. This review highlights the recent advancements in ceramic matrix composites, high-entropy ceramics, and polymer-derived ceramics, alongside various fabrication techniques such as three-dimensional printing, advanced sintering, and electric-field-assisted joining. Beyond the fabrication process, we emphasize how different processing methods impact microstructure, transport properties, and performance metrics relevant to catalysis. Additive manufacturing routes, such as direct ink writing, digital light processing, and binder jetting, are discussed and normalized based on factors such as relative density, grain size, pore architecture, and shrinkage. Cold and flash sintering methods are also examined, focusing on grain-boundary chemistry, dopant compatibility, and scalability for catalyst supports. Additionally, polymer-derived ceramics (SiOC, SiCN, SiBCN) are reviewed in terms of their catalytic performance in hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, and CO₂ reduction reaction. CeO₂-ZrO₂ composites are particularly highlighted for their use in environmental catalysis and high-temperature gas sensing. Furthermore, insights on the future industrialization, cross-disciplinary integration, and performance improvements in catalytic applications are provided. Full article

This study investigates the impact of non-uniform carbon sphere diameter distributions on the structural and electrochemical performance of catalyst layers (CLs) in proton exchange membrane fuel cells (PEMFCs), utilizing the lattice Boltzmann method (LBM) for detailed simulations. The impact of carbon sphere diameter range and gradient distribution on oxygen transport, electrochemical reactivity, and catalyst layer morphology was investigated. The results show that gradient designs of carbon sphere diameters effectively modulate pore size distribution, electrochemically active surface area, and oxygen diffusion pathways within the CL. Specifically, placing larger carbon spheres near the gas diffusion layer improves pore connectivity and oxygen transport, while smaller spheres near the membrane enhance the availability of reaction sites. The three-layered gradient design, particularly the L-M-S configuration, demonstrated superior oxygen distribution, reduced concentration gradients, and increased current density by 15.4%. These findings underline the importance of optimizing carbon sphere diameter distributions for enhancing CL performance. This study offers a novel framework for designing catalyst layers with improved mass transport and electrochemical efficiency, providing significant insights for the future development of high-performance PEMFCs. Full article

Cystinosis is a rare lysosomal storage disorder characterized by defective cystine transport and progressive multi-organ damage, with the kidney being the primary site of pathology. In addition to the traditional perspective on lysosomal dysfunction, recent studies have demonstrated that cystinosis exerts a substantial impact on cellular energy metabolism, with a particular emphasis on oxidative pathways. Mitochondria, the central hub of ATP production, exhibit structural abnormalities, impaired oxidative phosphorylation, and increased reactive oxygen species. These factors contribute to proximal tubular cell failure and systemic complications. This review highlights the critical role of energy metabolism in cystinosis and supports the emerging idea of organelle communication. A mounting body of evidence points to a robust functional and physical association between lysosomes and mitochondria, facilitated by membrane contact sites, vesicular trafficking, and signaling networks that modulate nutrient sensing, autophagy, and redox balance. Disruption of these interactions in cystinosis leads to defective mitophagy, accumulation of damaged mitochondria, and exacerbation of oxidative stress, creating a vicious cycle of energy failure and cellular injury. A comprehensive understanding of these mechanisms has the potential to reveal novel therapeutic avenues that extend beyond the scope of cysteamine, encompassing strategies that target mitochondrial health, enhance autophagy, and restore lysosome–mitochondria communication. Full article

Nucleated erythroid cells (NECs) have emerged as active participants in immune responses in addition to their canonical oxygen transport function. The subpopulations and immune heterogeneity of chick erythroid cells (ch-ECs) upon infection have not been fully characterized. Single-cell RNA sequencing (scRNA-seq) was used to profile ch-ECs in chicks infected with avian pathogenic Escherichia coli (APEC). Unsupervised clustering uncovered ten distinct ch-EC subpopulations (C1–C10), with significant compositional shifts between infected and control groups. Pseudotime analysis revealed a developmental continuum: C1, C3, C5, and C9 as early progenitors; C2, C4, C6, C7, and C10 as mature erythroid cells; and C8 as a naive population. We revealed 62 immune-related genes, including protein kinases and heat shock proteins, and subpopulation-specific differentially expressed genes (DEGs) linked to immune functions. SCENIC analysis revealed Fos, Srf, and Stat3 as key transcription factors with elevated regulon activity and specificity following infection. Subpopulations C2, C4, C6, and C7, which exhibited marked abundance changes, were scrutinized for immune relevance through integrated multi-omics analysis. Immune-related genes including FOS, AKAP9, HS6ST1, GAB3, TFRC, HSPA8, HSP90AA1, and DNAJB6 were identified. Enrichment analysis indicated activation of the MHC class I antigen presentation pathway, while pathways such as Mitogen-Activated Protein Kinase (MAPK) signaling, NOD-like receptor (NLR) signaling, and the heat shock response were found to be suppressed. In conclusion, this study delineates the immune gene repertoire and signaling networks of ch-ECs during APEC infection, offering new perspectives on NEC immunoregulatory functions. Full article