Search Results (1,848)

Several studies have investigated counterflow and concurrent flow in channels separated by a membrane to simulate mass transfer through membranes; however, few of them have used computational fluid dynamics (CFD). The current study aimed to numerically simulate and physically describe the distribution of pressure and velocity in counter-current flow by solving Navier-Stokes (N-S) equations in the channel and membrane pores (vertical channels). This is in contrast to most previous studies, in which the channel flow was simulated using N-S equations while ultra-filtration membrane flow was simulated using Darcy’s law. Consequently, the current study was executed using a CFD simulation to achieve several significant features: avoiding the execution of experimental tests, reducing the effort of model design and the expense and time consumption of fabrication, and facilitating the easy observation of variations in the pressure and the horizontal and vertical velocity for each point in the model. Two-dimensional CFD methods directly simulated the flow in channels and membrane pores to solve the N-S equations for each point in the whole domain, for which the velocity (horizontal and vertical) and pressure were calculated. In the current study, it was found that the pressure decreased from the inlet to the outlet of the channel, the horizontal velocity decreased from the inlet to the middle of the channel length and then increased to the outlet of the channel, and the vertical velocity decreased from the inlet to the middle of the channel length (L/2) with an upward direction (positive) and from L/2 to the outlet of the channel with a downward direction (negative). The analytical solution (1D model) was used to validate a numerical simulation (CFD) for the current study, but there were slight differences in the results between them. The results were perfectly explored and displayed the flow distribution patterns inside the channels and the membrane pores (vertical channels). The current study model represents the hemodialysis process. Full article

Brucella anthropi is an emerging opportunistic pathogen characterized by intrinsic resistance to most $\beta$-lactams. However, the acquisition of carbapenem resistance in this species has rarely been documented in environmental, animal, or clinical settings. In this study, a multidrug-resistant strain, SBA01, was isolated from wastewater-irrigated soil. SBA01 exhibited phenotypic resistance to carbapenems and colistin, the latter being independent of mcr genes. Genomic analysis localized bla_IMP-1 on a stable 21 kb plasmid maintained by a Type II toxin–antitoxin system. While non-self-transmissible, this plasmid was mobilized to Escherichia coli and Klebsiella pneumoniae via an unclassified 50 kb helper plasmid. Additionally, a 217 kb prophage-bearing megaplasmid was identified, enhancing genomic plasticity. Genomic screening identified 32 putative virulence determinants, including markers associated with host interaction. Risk profiling indicated an elevated hazard index for SBA01, driven by the convergence of multidrug resistance, cryptic mobilization capacity, and opportunistic survival traits. These findings position B. anthropi as a resilient environmental reservoir for clinically relevant carbapenemases. Expanding surveillance frameworks to include such adaptive hosts is necessary to better evaluate potential occupational exposures at the wastewater–soil interface. Full article

Background: Wastewater treatment plants (WWTPs) are hotspots of antimicrobial resistance (AMR) due to inputs from diverse anthropogenic sources. Aeromonas spp., ubiquitous in aquatic environments, often carry clinically relevant antibiotic resistance genes (ARGs) and can persist beyond fecal contamination indicators, making them promising sentinel organisms for AMR dissemination. The aim of this study was to assess the suitability of Aeromonas spp. in this role by characterizing resistance profiles, associated virulence factor genes (VFGs), genetic mobility, and persistence across wastewater and drinking water treatment processes in the Barcelona metropolitan area, Spain. Methods: Isolates were phenotypically characterized and screened for ARGs, VFGs, integrons, and heavy metal tolerance genes, followed by whole-genome sequencing (WGS). Biofilm formation was assessed in vitro. Conjugation assays with Escherichia coli evaluated horizontal gene transfer (HGT) potential. Results: A total of 428 antibiotic-resistant Aeromonas spp., the most abundant antibiotic-resistant bacteria isolated during the 2023 sampling campaigns from two WWTPs and one drinking water treatment plant (DWTP), were characterized. Trimethoprim/sulfamethoxazole (SXT) non-susceptibility was most frequent (72%), followed by cefoxitin resistance (65.4%). The sul1 (57.5%) and bla_MOX (78.6%) genes predominated among SXT- and β-lactam-resistant isolates. The merA gene was detected in 23.6%; 97.9% harbored at least one VFG (aerA, act, fla, alt, or hlyA), and 70.3% carried intI1. Half formed biofilm. Conjugation confirmed bi-directional HGT, and WGS revealed persistent ST3458 clones across treatment stages. Conclusions: WWTPs and DWTPs act as reservoirs of antibiotic-resistant Aeromonas spp., demonstrating persistence and HGT potential. Findings support their use as sentinel organisms for AMR surveillance in aquatic environments and for assessing treatment efficacy, highlighting variability across treatment types and locations, and reinforcing their relevance for urban water reclamation monitoring. Full article

Dual-phase layered microstructures containing alternating regions of soft and hard phases can produce alloys with a unique combination of strength and ductility. In this study, the molecular dynamics (MD) method was utilized to simulate nanoindentation of a Ni/NiTi/Ni nanostructured film (NSF). This film features a unique alternating FCC/B2/FCC microstructure, in which the B2-phase NiTi acts as a superelastic shape memory alloy (SMA). The results indicate that Ni/NiTi/Ni NSF significantly reduces its hardness due to the superelasticity of the B2 phase. The presence of the NiTi interlayer effectively blocks the propagation path of dislocations and stacking faults by transforming the local dislocations transferred from the upper layer into a large-scale coordinated phase transition, significantly reducing local deformation misalignment. As the thickness of the surface film λ increases, the dislocation slip plane propagating horizontally appears in the upper pure Ni layer. The thicker the surface film, the more horizontal slip planes are formed. This study provides new insights into the contact mechanical behavior of nanostructured films based on NiTi shape memory alloys from the perspective of atomic scale. Full article

Machine learning was employed to make fluid agnostic laminar heat transfer prediction in supercritical conditions, encompassing three fluids (sCO₂, sH₂O, sC₁₀H₂₂) representing a wide range of operating conditions. High-fidelity training data, consisting of both non-dimensional and dimensional (operating parameter) as inputs and Nu and T_wall as outputs, were generated from grid-converged, steady-state, computational fluid dynamic (CFD) simulations. The Random Forest (RF) algorithm outperformed the artificial neural networks (ANNs) across all scenarios on the small multi-fluid dataset (~1600 data points) employed during the training process. When using non-dimensional parameters as inputs, Nu prediction fidelities were better than T_wall predictions for both ML algorithms across both horizontal and vertical configurations. The RF model trained on data from a specific flow configuration (horizontal/vertical) could predict T_wall within an accuracy of +/−1% with dimensional, operational parameters as inputs while being agnostic to the working fluid. Furthermore, by including the gravity vector as an additional variable during the training process, the RF model could predict T_wall accurately in a mixed, multi-fluid dataset containing data from both horizontal and vertical configurations. Full article

Horizontal transfer of mitochondrial DNA into the nuclear genome generates nuclear mitochondrial sequences (NUMTs), which serve as molecular fossils reflecting long-term mitochondrial–nuclear interactions and genome evolution. However, the biological mechanisms governing NUMT integration, retention, and evolutionary fate remain incompletely understood in domesticated animals. Here, using the latest pig reference genome assembly (Sscrofa11.1), we present a comprehensive genome-wide characterization of NUMTs in pigs and provide new insights into their genomic distribution and evolutionary constraints. We identified 513 high-confidence NUMTs, of which 460 were chromosomally mapped, accounting for 0.0106% of the nuclear genome. Beyond increased detection, our analyses reveal that pig NUMTs exhibit non-random origins, preferentially integrate into genomic regions under weak selective constraint, and are frequently associated with repetitive elements, consistent with a DNA repair-mediated insertion mechanism. NUMTs predominantly occur as short, fragmented sequences and show signatures of long-term neutral evolution, while insertions disrupting coding sequences are strongly selected against. Synteny-based analyses further identified clustered NUMT regions and duplicated NUMTs, suggesting secondary genomic duplication events following initial integration. Comparative analysis with the earlier Sscrofa10.2 assembly demonstrates that improved genome quality substantially enhances NUMT detection, particularly in repetitive and GC-rich regions, clarifying previously ambiguous sequence-context associations. Together, this high-quality pig NUMT map provides a robust foundation for future functional, evolutionary, and population-level investigations and contributes to the conservation and utilization of pig genetic resources. Full article

Background: Tumor-derived small extracellular vesicles (sEV), which we call TEX, carry a cargo of molecules that resembles the producer tumor cells. Circulating freely in body fluids, TEX potentially serve as a liquid tumor biopsy. TEX horizontally transfer their cargo to various recipient cells, imparting to them pro-tumor activity. Mechanisms of TEX-driven reprogramming might involve nucleic acids, especially double-stranded (ds)DNA. Methods: TEX isolated from supernatants of human tumor cells were identified as sEV, based on their size, endocytic origin and morphology. TEX treated with DNase/RNase cocktail were examined by transmission and cryo-electron microscopy and tested for biologic activity. DNA was extracted from enzyme-treated TEX, quantified by Qubit and analyzed for fragment sizes. The presence of genomic DNA in TEX was confirmed by PCR, and sequencing of the TP53 gene fragment for a mutational signature was performed. Results: Enzymatic and microscopic studies of TEX showed that nucleic acids are present in the biocorona on the outer surface. Their removal interfered with the biocorona integrity. A short TEX exposure to DNase/RNase altered their morphology without impairing vesicle functions; longer treatments induced TEX re-organization into smaller membrane-bound vesicles. The TEX lumen contained long fragments of protected genomic DNA with a mutational signature reflecting that of the tumor. Conclusions: Nucleic acids present on the TEX surface support the vesicular integrity. The TEX lumen contains membrane-protected large (ds)DNA fragments with the mutational signature of the parent tumor. The presence of surface and luminal nucleic acids in TEX, and especially their mutational signature, suggests that TEX may serve as highly promising cancer-specific biomarkers. Full article

Synanthropic cockroaches, especially Blattella germanica and Periplaneta americana, are persistent pests of human dwellings, healthcare facilities, food establishments, farms, and transport infrastructure. Accumulating field and laboratory studies indicate that synanthropic cockroaches carry clinically important bacteria, fungi, and parasites, including multidrug-resistant strains harbouring extended-spectrum β-lactamase, carbapenemase, and other antimicrobial-resistant determinants. Cockroaches acquire these organisms from sewage, waste, food residues, animal excreta, and contaminated clinical environments, and retain them on the cuticle and within a complex gut microbiota. Dissemination is predominantly mechanical, via contact transfer and deposition of regurgitate and faeces on food, equipment, and surfaces, but may be amplified by gut colonisation, microbial interactions, and horizontal gene transfer within the cockroach microbiome. In hospitals, cockroaches can connect high-burden reservoirs (drains, waste areas, kitchens) with vulnerable units, including intensive care units (ICUs), neonatal intensive care units (NICUs), burn units, and haemato-oncology wards. In food and livestock systems, they may contaminate housing, ingredients, and finished products, enabling spillover along supply chains and at ports. This review synthesises current evidence and highlights the following priorities: integrate cockroaches into infection prevention, food safety, and biosecurity; incorporate cockroach sampling into antimicrobial resistance (AMR) and genomic surveillance; and advance mechanistic research on cockroach–microbiota–pathogen interactions to improve pest management and safely explore cockroach-derived antimicrobial compounds. In this review, we distinguish external mechanical carriage (cuticular contamination) from internal gut carriage; we use “gut colonisation” only when persistence/replication or prolonged shedding is demonstrated. Full article

This work experimentally investigates the behavior of a new indoor air conditioning system based on the application of Peltier cells in a Horizontal Air–Ground Heat Exchanger (HAGHE). To this end, a laboratory-scale prototype focusing exclusively on the terminal section of the system was developed and tested under controlled conditions. A series of configurations was tested, each representing an evolution of the previous one. The results highlight the strong dependence of system performance on airflow velocity, applied voltage, and heat dissipation effectiveness, demonstrating both the potential and the critical limitations of the proposed configurations. The most promising results were obtained in the advanced (fourth and fifth) configurations, yielding average temperature increases of approximately +1.9 °C on the hot flow and decreases ranging from −1.0 °C to −1.7 °C on the cold flow at moderate total voltages (40–50 V) and higher airflow velocities (0.5–0.6 m/s). In line with the principles of the circular economy, the prototype was constructed using recycled materials, including plastic pipes and Peltier cells recovered from discarded devices. Full article

The expansion of tropical specialty livestock farming raises urgent concerns about airborne pathogen and antibiotic resistance dissemination. Ostrich farming, characterized by high-density stocking and feed exposure, yet their microbial ecology remain poorly characterized. This study analyzed 48 bioaerosols samples from an ostrich farm in Hainan, China, across dry and rainy seasons using 16S rRNA sequencing and metagenomics. The bacterial community were dominated by Firmicutes, Proteobacteria, and Actinobacteria, followed by Staphylococcus, Bacillus, and Acinetobacter as predominant genera, with particle size significantly shaping their structure. Large particles (>7.0 μm) carried higher species richness, while medium particles (2.1–3.3 μm) exhibited the highest diversity and evenness. Notably, small particles (0.65–1.1 μm), which can penetrate deep into the lungs, were enriched with Brevibacillus and Corynebacterium. Metagenomic analysis identified 638 antibiotic resistance genes (ARGs), dominated by efflux pump-associated determinants. The detection of clinically relevant ARGs (e.g., mcr-1 and bla_TEM) reflects the genetic potential of the airborne resistome, rather than confirmed resistance phenotypes or active horizontal gene transfer. Functional analysis revealed a strong potential for organic matter degradation, driven by abundant carbohydrate-active enzymes (CAZymes) and their corresponding CAZyme genes, as well as a nitrogen cycle dominated by assimilation and reduction pathways, while genes for nitrogen fixation and nitrification were absent. Our findings demonstrate that ostrich farming enhanced airborne microbial diversity and functional potential, facilitating the ARG dissemination and nitrogen transformation. This study provides critical insights into the ecological and health risks of bioaerosols in tropical livestock farms, informing environmental monitoring and risk management strategies. Full article

Antimicrobial resistance (AMR) constitutes one of the most severe and pressing threats to global public health, food security, and environmental integrity. This review synthesizes current evidence across interconnected One Health domains—humans, animals, food, and the environment—to delineate the scope, mechanisms, and drivers of AMR transmission. Our analysis reveals three principal findings. First, the scope of AMR is alarmingly extensive, with antibiotic-resistant bacteria (ARB) and genes (ARGs) now pervasive across all four ecological compartments, transcending traditional clinical boundaries. Second, this widespread distribution is critically facilitated by horizontal gene transfer mechanisms, particularly via mobile genetic elements such as plasmids, which enable ARGs to disseminate rapidly between diverse bacterial populations across different ecosystems. Third, we identify multiple interconnected drivers that actively promote this cross-ecosystem spread, encompassing both evolutionary and transmission drivers. By characterizing these critical transmission pathways and underlying drivers, this review provides an integrated framework to identify critical transmission risks and inform integrated strategies for mitigating antimicrobial resistance across One Health domains. Full article

The soil–water interface (SWI) represents a critical biogeochemical hotspot where steep physicochemical gradients across millimetre-to micrometre-scales create diverse ecological niches controlling nutrient cycling, carbon stabilisation, and contaminant transformation. This review synthesises emerging understanding of micro-scale microbial dynamics, biofilm architecture, and functional processes shaping SWI ecosystems. We examine redox stratification driving microbial community assembly, biofilm-mediated nutrient trapping and soil aggregate stabilisation, and dynamic drivers including hydrological fluctuations, viral lysis, and differential transport at gas–water versus solid–water interfaces. Advanced methodologies, microsensor profiling, cryo-sectioning, spatially resolved metatranscriptomics, and non-destructive imaging, now enable unprecedented resolution of SWI microhabitat chemistry and microbial organisation. Horizontal gene transfer within interface biofilms accelerates adaptive responses to environmental stressors. Integration of micro-scale observations into ecosystem-level models remains challenging but essential for predicting soil carbon sequestration, contaminant fate, and microbial resilience under climate change. Strategic SWI management through biofilm engineering and controlled redox manipulation offers novel pathways for sustainable agriculture and bioremediation, though it requires careful balance of multiple ecosystem functions. Full article

Cheese ripening is slow and costly, driving interest in accelerating maturation. This study aimed to isolate a safe, efficient adjunct starter from traditional Sichuan yak yoghurt, a niche rich in stress-adapted lactic acid bacteria. From 295 isolates, 15 strains tolerant to high salt, low pH, and low temperature were selected. Using acidification, autolysis, proteolysis, and peptidase activity as indices, principal component analysis identified Limosilactobacillus fermentum 270 as the best candidate. Phenotypic assays showed no haemolysis, gelatin liquefaction, indole production, or amino acid decarboxylase activity. Whole-genome sequencing confirmed species identity and revealed 52 protease/peptidase genes, complete pathways for diacetyl/acetoin biosynthesis and branched-chain amino acid conversion, and no functional biogenic amine synthesis genes. Stress-related genes (F-ATPase, glycine-betaine transport, cold-shock proteins) support cheese adaptability. Antibiotic resistance gene homologs were mainly chromosomal and unlinked to mobile genetic elements; a functional CRISPR-Cas system lowers horizontal transfer risk. The strain was developed as a freeze-dried direct-vat starter (97.3% viability). Orthogonal optimisation of yak Gouda cheese-making defined best conditions: 0.018% adjunct, 45 min acidification, pH 5.8, and 30% curd washing. L. fermentum 270 thus combines proteolytic, flavour-enhancing, genetic safety, and processing traits, offering a promising adjunct for accelerated cheese ripening. Full article

To achieve an all-directional and high-speed, high-accuracy autofocus (AF) function, we propose a CMOS image sensor with a Twisted Photodiode (PD) structure. The developed 3D-stacked back-side illuminated (BSI) sensor employs the Twisted PD, which enables equivalent angular response characteristics in both the horizontal and vertical directions for the two PDs integrated within a single pixel, thereby realizing AF detection for all pixels and all directions. This paper describes the Twisted PD structure that enables all-directional AF and presents an analysis of charge transfer behavior in this unique 3D configuration. In this paper, “all-directional” refers to robustness with respect to subject direction. Full article

Fusarium is a diverse genus of filamentous fungi that has long been recognized for its importance in plant disease and food security. Beyond its agricultural impact, a growing number of studies now show that Fusarium species can also act as opportunistic pathogens in animals and humans. This review synthesizes current knowledge on Fusarium biology by integrating perspectives from plant pathology, veterinary science, and medical mycology. We examine how shared virulence mechanisms, environmental reservoirs, and genomic plasticity—including accessory chromosomes and horizontal gene transfer—facilitate adaptation across plant, animal, and human hosts. We also consider the role of environmental change in shaping the distribution and pathogenic potential of this genus. By bringing together evidence that is often scattered across disciplines, this review emphasizes the need to move beyond host-specific views and highlights Fusarium as a useful model for understanding fungal adaptability and cross-kingdom pathogenicity within a One Health framework. Full article