Search Results (14,115)

Oxygen stoichiometry critically governs the phase stability and physical properties of transition-metal oxides, yet a unified understanding of how oxygen-stoichiometry-driven phase reconstruction underlies the cooperative evolution of multiple physical properties in SrCoO_x remains lacking. Here, high-quality epitaxial brown millerite SrCoO_2.5 and perovskite SrCoO_3−δ thin films were grown by pulsed laser deposition under controlled oxygen conditions. Their structural, magnetic, electrical, optical, and photocatalytic properties were systematically compared. SrCoO_2.5 exhibits antiferromagnetic insulating behavior, infrared-dominant transmittance, and higher photocatalytic activity, whereas SrCoO_3−δ shows ferromagnetism, much lower resistivity, and strong optical opacity. First-principles calculations reveal that oxygen-stoichiometry-driven phase reconstruction strongly modifies the electronic structure, accounting for the distinct magnetic, transport, and optical responses. These results establish a direct correlation between oxygen stoichiometry, structural transformation, and multifunctional properties in SrCoO_x, highlighting oxygen-vacancy ordering as an effective route to tailoring correlated oxide functionalities. Full article

Maintaining asphalt pavements requires substantial quantities of materials and energy, which significantly contribute to greenhouse gas emissions in the road infrastructure sector. This study quantified the carbon dioxide equivalent (CO₂e) emissions associated with a maintenance and rehabilitation plan for an asphalt pavement using a simplified life-cycle perspective integrated with the Highway Development and Management Model (HDM-4). The methodology combined HDM-4 to define a 35-year intervention plan (2022–2057) with CO₂e emission factors for three quantified components: material production, transportation, and construction machinery operation. The approach was applied to a 7.8 km section of the Mexicali–San Felipe highway in Baja California, Mexico. The results indicate that the intervention plan generated approximately 2483.9 t CO₂e over the 35-year analysis period. Reconstruction was the most carbon-intensive activity, accounting for 1890 t CO₂e, while milling and overlay generated 292.15 t CO₂e per direction. Material extraction and production were the dominant sources of emissions, contributing about 70% of the total emissions in milling and overlay and 60% in reconstruction; in the latter case, transportation also represented a substantial share (35%) due to long haul distances. These findings show that the proposed approach can identify the most emission-intensive activities and processes within pavement maintenance plans and provide quantitative environmental criteria to support more sustainable road management decisions. Full article

This study aimed to elucidate the molecular mechanisms underlying phenotypic divergence between two Lentinula edodes strains, Le_L and Le_S, which exhibit distinct fruiting body morphologies. While phenotypic variation among mushroom strains has been widely observed, the relative contributions of transcriptional regulation and structural genomic variation to these differences remain poorly understood. Comparative transcriptome analysis identified 8541 differentially expressed genes (DEGs), revealing clear functional divergence between the two strains. Genes upregulated in Le_S were predominantly enriched in ribosomal components and translation-related processes, indicating enhanced protein synthesis activity. In contrast, Le_L-upregulated genes were associated with transporters, transcription factors, and diverse metabolic pathways, suggesting broader regulatory and physiological functions. Protein–protein interaction network analysis further highlighted distinct regulatory architectures, with ribosomal proteins forming highly interconnected hub gene modules in Le_S, whereas Le_L hub genes were functionally diverse and included multiple members of the Major Facilitator Superfamily (MFS). Ortholog analysis across 33 L. edodes strains demonstrated that most hub genes were conserved, indicating their roles as core genetic components. Despite widespread genome-wide variation, including 7931 SNPs and 1149 INDELs, sequence variation within hub genes was limited, and allele-specific expression analysis revealed no significant allelic imbalance. In contrast, presence–absence variation (PAV) analysis identified structural differences affecting MFS transporter genes, which were absent in Le_S but present and upregulated in Le_L. Collectively, these findings suggest that structural genomic variation, particularly involving transporter genes, may play a more prominent role than sequence-level variation in driving phenotypic divergence. This study provides new insights into the genetic basis of strain-specific traits in L. edodes and highlights the importance of integrating multi-level genomic analyses. Full article

Magnesium is an essential divalent cation required for adenosine triphosphate (ATP)-dependent reactions, nucleic acid metabolism, and ribosomal stability. Bacteria depend on specialized transport systems to maintain intracellular Mg²⁺ homeostasis as it cannot freely cross the phospholipid bilayer. During infection, host nutritional immunity restricts metal availability, and magnesium limitation within the phagosome compromises bacterial metabolism and stability. This review summarizes the major bacterial magnesium transport systems and their roles in survival and pathogenicity, with an emphasis on Salmonella and extension to clinically relevant ESKAPE pathogens. We focus on the PhoPQ-regulated MgtA, MgtB, and MgtC system, in which low magnesium, acidic pH, and other host-derived signals activate PhoPQ to induce mgt gene expression. MgtA and MgtB act as high-affinity P-type ATPases, whereas MgtC promotes bacterial survival within the intramacrophage environment by inhibiting bacterial F-type ATP synthase through specific interactions with subunit a. We also discuss CorA as a conserved channel for basal Mg²⁺ uptake and MgtE as a Mg²⁺-selective channel whose gating responds to intracellular Mg²⁺ and ATP. Finally, we consider the conservation and variation in these systems across pathogenic bacteria and their potential as therapeutic targets for antimicrobial development. Full article

Organic-type solar cells containing an active layer of block copolymer donor PTB7-Fx (x = 0, 20, and 100), based on benzo [1,2-b:4,5-b’]dithiophene and variably fluorinated thieno [3,4-b]thiophene units, and fullerene acceptor [6,6]phenyl-C₇₁-methylbutyrate, were constructed. The active layer thin film of the solar cells was obtained from a dichlorobenzene solution at an established concentration via spin-coating of the donor–acceptor mixture in the presence of solvent additives such as 3% diiodooctane and 1% triethyl phosphate. Organic photovoltaic elements with normal device architecture were prepared on glass substrates using an indium tin oxide anode, a spin-coated hole transporting layer of poly(ethylene dioxythiophene):polystyrenesulfonate, the aforementioned active layer, followed by an electron transporting layer of zinc oxide nanoparticles, and finally a magnetron sputtered silver (Ag) top-electrode. The optical properties, thin film morphology, and the thickness of the active layers were investigated. Additionally, current density–voltage characteristics and impedance spectra of photovoltaic devices were measured. It was found that PTB7-Fx:PC₇₁BM-based solar cells processed in the presence of two types of solvent additives, diiodooctane and triethyl phosphate, with a sputtered Ag top-electrode display similar absorption and quantum efficiency spectra, as well as comparable current density–voltage characteristics and efficiencies to the same devices fabricated without additives. The diiodooctane solvent additive preferably dissolves the fullerene component and has a positive effect on fill factor enhancement, impedance spectra improvement, and amelioration in charge carrier transport and collection, whereas the triethyl phosphate solvent additive preferentially dissolves the copolymer donor and has a more pronounced impact on the refined morphology of the thin film active layers. Full article

Primary succession following glacier retreat provides a natural system for testing whether soil development simply shifts fine roots along a single acquisitive–conservative axis orinstead changes the nutrient-acquisition pathway that dominates at the community level. We hypothesized a stage-dependent sequence, from substrate-limited exploration, to transient morphological capture, and finally to rhizosphere-mediated biochemical mobilization. To test this idea, we quantified fine-root morphology, absorptive-transport partitioning, anatomy, phosphatase activity, exudation, community-scale belowground structure, and soil and rhizosphere properties across woody communities representing approximately 20, 40, and 90 years since deglaciation in the Hailuogou Glacier foreland. Across succession stages, bulk density and pH declined, whereas field capacity, soil carbon, and soil nitrogen increased, indicating rapid development of the belowground resource environment. Fine-root strategies did not fall along a single acquisitive–conservative continuum. Instead, morphological nutrient capture peaked at intermediate succession: the 40-year stage had the highest specific root length, specific root area, absorptive-to-transport root length ratio, and root nitrogen concentration. In contrast, the 90-year stage showed lower specific root length but higher dry matter content, thicker cortex, greater standing fine-root biomass, larger rhizosphere volume, higher phosphatase activity, and greater area-based carbon exudation. This late-successional syndrome coincided with stronger extracellular enzyme activity, larger dissolved organic carbon and nitrogen pools, and higher microbial biomass, despite negative net nitrogen mineralization. Species-level analyses showed that biochemical-input traits were jointly shaped by successional stage, species identity, and their interaction. Together, these results show that primary succession did not simply increase or decrease root acquisitiveness. Instead, as soils developed, it changed the nutrient-acquisition pathway that dominated, with direct implications for nutrient cycling and vegetation dynamics in rapidly developing glacier-foreland ecosystems. Full article

Maritime transport is under increasing pressure to cut greenhouse gas and pollutant emissions to meet global decarbonization goals and tighter environmental standards. Ship electric propulsion systems offer a promising solution for short-range maritime operations, particularly for small vessels and coastal activities. Full-electric vessels can significantly reduce operational emissions; however, a key challenge is the extensive charging time for onboard energy storage, which can affect operational continuity and logistical efficiency. This study examines mission planning and energy management for a hybrid multi-source electric mail boat operating in the Aeolian archipelago. It evaluates the viability and performance of a daily inter-island route powered by a high-temperature methanol fuel cell, batteries, and photovoltaic panels. A routing and simulation framework was developed to model the boat’s itinerary among seven islands, accounting for realistic navigation speeds, scheduled stops, solar energy availability, and battery state-of-charge constraints. The study analyzes distance, travel time, energy consumption, solar power generation, and fuel–electric usage with high temporal resolution, enabling detailed analysis of power flows during sailing and docking. Several operational strategies were assessed, including periods of increased speed supported by battery assistance and fuel–electric cell output, combined with coordinated energy management to keep battery levels above a lower acceptable threshold while completing the route in a single day. The methodology provides a practical tool for planning low-emission island networks and supports the integration of innovative energy systems into small electric workboats operating in specific maritime regions. Full article

Infrared photodetectors are important for military, medical, and environmental applications. Dual-color quantum well infrared photodetectors (QWIPs) are attractive because they can provide multi-spectral information, but their performance is often limited by high dark current. In this study, we designed and fabricated two dual-color QWIPs. Sample A exhibits rectification-like dark-current behavior, whereas Sample B shows a nearly symmetric current–voltage characteristic together with an approximately two-order-of-magnitude reduction in dark current under the same operating condition. By combining secondary ion mass spectrometry (SIMS), scanning spreading resistance microscopy (SSRM), energy-band simulations, and optoelectronic characterization, we show that Sample B exhibits a larger disparity in effective carrier distribution between the two quantum-well groups than Sample A. The experimental results and simulations consistently indicate that this disparity, together with the higher barrier design, is associated with a redistribution of the internal potential and a stronger voltage drop across the lightly doped region, which is consistent with reduced thermally activated carrier transport. Although the lower carrier concentration in the lightly doped wells is accompanied by reduced blackbody responsivity, the stronger suppression of dark current leads to a higher peak blackbody detectivity under identical blackbody-illumination conditions. At 50 K and −1.5 V, the peak blackbody detectivity of Sample B is approximately four times that of Sample A. These results support the conclusion that combining barrier-height design with controlled inter-group carrier disparity is an effective strategy for tuning carrier transport and improving the peak blackbody detectivity trade-off in dual-color QWIPs within the conditions examined here. Full article

Cycling is widely recognized as a sustainable urban mobility solution, and many municipalities focus on cycling infrastructure expansion to promote improved environmental sustainability. However, the current literature on cycling has predominantly focused on safety and health benefits, while the environmental benefits including GHG mitigation benefits remain less explored. To summarize findings from the current literature that explore the GHG emissions-related benefits (or costs) of cycling infrastructure, we conducted a literature review using five major scientific databases, following the PRISMA guidelines. Out of 824 screened records, 17 studies met the inclusion criteria. Most studies were published in the last decade, reflecting a limited but growing interest in this topic. The current analytical approaches include mode shift analysis, life cycle assessment, and scenario modelling. Among these, mode shift analysis (i.e., assessing the potential benefits related to replacement of car trips with cycling) remains a commonly used method. We found that cycling offers significant operational benefits by reducing GHG emissions, especially in the context of large-scale expansions of cycling infrastructure. Existing research indicates that even when embodied emissions are considered, bicycle is a more sustainable mode of transportation compared to cars or even public transit. However, emissions associated with installation and maintenance of cycling infrastructure may sometimes negate the GHG benefits associated with additional cycling. We discussed gaps in the current literature and directions for future research. Full article

Solid oxide electrolysis cells (SOECs) are regarded as a promising technology for sustainable hydrogen production because of their high energy conversion efficiency. In this study, a multiphysics numerical model combined with a random particle packing framework was used to evaluate the influence of anode microstructural parameters on the electrochemical performance of a button-type SOEC. The effects of anode porosity, particle size, and electrode thickness on current density were systematically analyzed. Increasing porosity from 0.3 to 0.5 reduced the current density because of the decreased fraction of electrochemically active material. Increasing the anode particle size from 50 to 300 nm significantly shortened the triple-phase boundary (TPB) length, leading to a decrease in current density from 6289 to 5502 A m⁻². The effect of anode thickness reflects a trade-off between electrochemical activity and gas transport, with the current density increasing from 5502 to 5940 A m⁻² as the thickness increased from 10 to 20 μm. Overall, the results highlight the coupled roles of reaction-site availability and oxygen transport in determining SOEC performance. This study provides a parametric assessment of how anode microstructure affects SOEC performance and may support the structural optimization of SOEC oxygen electrodes. Full article

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), remains a major cause of morbidity and mortality worldwide, particularly due to the emergence of drug-resistant strains. Membrane-active antimicrobial peptides (AMPs) represent attractive therapeutic candidates because they target bacterial envelope integrity and disrupt essential cellular processes. We evaluated two rationally designed LL-37-derived peptides: a truncated C-terminally amidated analog (LL37-1) and a modified variant incorporating N-terminal acetylation and a single D-amino acid substitution (D-LL37). Dose–response analysis demonstrated that D-LL37 exhibited greater antimycobacterial potency, with lower inhibitory concentrations of 90% (IC₉₀) and 50% (IC₅₀) values (18.40 ± 0.39 μM and 10.11 ± 0.60 μM, respectively) compared with LL37-1 (25.44 ± 0.36 μM and 15.45 ± 1.40 μM). Fluorescence-based permeability assays revealed partial membrane disruption (36% and 44% at IC₉₀ for LL37-1 and D-LL37, respectively), which was supported by ultrastructural alterations observed by scanning electron microscopy, including bacillary shortening, rough surface formation, cell clusters, and the presence of cellular debris, all of which are consistent with membrane damage. RT-qPCR analysis demonstrated significant upregulation of the P-type ATPase genes ctpF, ctpA, and ctpH following D-LL37 exposure. Collectively, these findings indicate that optimized LL-37-derived peptides exert antitubercular activity associated with envelope perturbation and coordinated activation of ion transport-related stress responses. Full article

Growing mobility demand and declining vehicle utilization motivate dual-use vehicles that can alternately transport passengers and freight. This work presents an early-stage utility value analysis to select a baseline concept and integrates it into model-based systems-engineering architecture development of an autonomous dual-use shuttle. Existing dual-use-capable shuttle concepts were screened and comparatively assessed using a utility value analysis with exclusion criteria and weighted evaluation criteria, including operational versatility, module exchange flexibility, infrastructure effort, battery positioning, and technology readiness. Criterion weights were derived by pairwise preference analysis, emphasizing the versatility of use scenarios. The highest-ranking concept, 101 Modular Mobility, was selected as the reference architecture. Subsequently, a SysML system model was developed in a MagicGrid-structured model-based systems-engineering (MBSE) process, covering stakeholder needs, key use cases such as transport service usage, module exchange, and automated charging, and the resulting system context and interfaces. The system model is augmented by a tailored Grey Box structural viewpoint within the MagicGrid workflow to make module boundaries and inter-module interfaces explicit for the modular dual-use shuttle architecture. The resulting model provides a traceable early architectural baseline for further refinement and subsequent verification activities. Full article

The epithelium represents the first line of defense against viral infection, yet the precise mechanisms by which viruses penetrate this complex barrier remain incompletely understood. Single-virus tracking (SVT) has emerged as a powerful fluorescence microscopy approach to directly visualize viral dynamics with nanometer spatial precision and millisecond temporal resolution. In this review, we survey recent progress in SVT methodologies, from image-based approaches to active feedback techniques, and assess their capacity to resolve viral behavior in physiologically relevant epithelial models. We further evaluate advances in virus labeling strategies—including fluorescent proteins, organic dyes, and nanoparticles—that enable prolonged observation while preserving infectivity. By integrating developments in optical instrumentation and molecular labeling, SVT is increasingly capable of capturing critical processes, including extracellular diffusion, receptor engagement, internalization, and trans-epithelial transport. Finally, we discuss current challenges, including limited penetration depth, photobleaching, and the complexity of 3D epithelial tissues, and outline future opportunities to extend SVT towards in situ and tissue-level studies. Together, these advances position SVT as a transformative tool to illuminate virus–epithelium interactions and guide therapeutic strategies. Full article

The emerging problem that microplastics pose to our society is reflected in the exponential growth in investigations devoted to uncovering their toxicological potential in humans. However, these studies present several limitations, one of the most significant being the use of microplastics that do not represent their environmental counterparts. In this study, we evaluated the impact of two types of polyethylene microplastics (27–32 µm)—non-fluorescent and fluorescent—on the liver and intestine, targeting mitochondria. FVB/n mice were subjected to a subacute exposure to two concentrations representative of human exposure (0.002% (w/w) and 0.006% (w/w)). Both types of microplastics impaired mitochondrial respiration through disruption of NADH-linked pathways, with more pronounced effects at the highest concentration of fluorescent MPs. Electron transport chain complexes, particularly CIII and CIV, were affected, partially explaining the observed alterations in mitochondrial respiratory capacity. An increased SOD and GPx activity supported the link between mitochondrial dysfunction and increased reactive oxygen species overproduction under MPs exposure. Hepatic mitochondrial lipid remodelling was detected following exposure to fluorescent microplastics, while intestinal epithelial cells displayed impaired mitochondrial activity together with compromised cellular integrity, indicative of stress response. In parallel, shifts in gut composition suggest that PE MPs may contribute to intestinal barrier dysfunction. Overall, fluorescent MPs induced more severe mitochondrial and biochemical disturbances in both the liver and the intestine than their non-fluorescent counterparts. Our findings highlight mitochondria as central targets for microplastic-induced toxicity and underscore the need for improved MPs models in toxicological research. Full article

The increasing accumulation of poly(ethylene terephthalate) (PET) waste poses a significant environmental challenge and highlights the need for sustainable, value-added recycling strategies. In this study, porous carbon derived from PET was synthesized via carbonization and chemical activation and subsequently combined with manganese dioxide (MnO₂) to fabricate hybrid electrodes for aqueous supercapacitors. The PET-derived carbon exhibits a highly microporous structure with a large specific surface area and functions as a conductive and mechanically stable matrix that improves MnO₂ dispersion, charge transport, and electrochemical utilization. Systematic electrochemical investigations reveal strongly electrolyte-dependent charge-storage behavior. In an alkaline electrolyte, the capacitance is dominated by MnO₂ pseudocapacitive redox reactions, whereas in a neutral electrolyte, the response is primarily governed by electric double-layer charge storage. In a ferricyanide-containing redox-active electrolyte, additional electrolyte-mediated faradaic processes significantly enhance the apparent electrochemical performance. Under these conditions, the hybrid electrodes deliver a high apparent specific capacitance of 240–250 F g⁻¹ at moderate current densities. The electrodes further demonstrate stable cycling behavior and high apparent Coulombic efficiency, reflecting time-dependent utilization of both MnO₂ pseudocapacitance and redox-active electrolyte species during charge–discharge. Crucially, this work demonstrates that PET-derived carbon/MnO₂ hybrid electrodes exhibit complex, electrolyte-controlled charge-storage mechanisms and underscores the critical role of electrolyte selection in accurately interpreting electrochemical metrics and optimizing the performance of sustainable supercapacitors based on recycled polymer-derived carbons. Full article