Antimicrobial resistance is a major public health threat, as resistant infections are harder to treat and carry greater risks. Using a One Health framework, this survey of freshwater samples investigated the influence of local land use on the occurrence of waterborne third-generation cephalosporin-resistant Enterobacterales (3GC-E) mediated through extended-spectrum β-lactamases (ESBLs) or plasmid-mediated AmpC (pAmpC) genes. A cross-sectional survey of 339 freshwater samples from 49 New Zealand sites was undertaken, encompassing catchments with urban, agricultural (namely dairy; sheep and beef; and mixed dairy, sheep, and beef), avian-impact, and low-impact (exotic/native forest) dominant land uses. 3GC-E (n = 63), including E. coli, Enterobacter, Citrobacter, and Klebsiella, were isolated from freshwater samples (n = 35), where urban (32), dairy (1), avian (1), and sheep and beef (1) were identified as the dominant land use. 3GC-E genome assemblies (n = 43) from freshwater were compared with human ESBL-E. coli (n = 467) assemblies. Waterborne 3GC-E. coli were phylogenetically diverse, represented by seven phylotypes and 20 sequence types (ST131, ST38, ST68, and ST219) associated with human infections, suggesting contamination with urban wastewater. Two freshwater E. coli harbored the plasmid-associated carbapenemase-encoding blaNDM-5-bleMBL gene cassette, which was absent from the human isolates. Two further freshwater E. coli and four human E. coli isolates carried pAA plasmids containing agg genes encoding for enteroaggregative E. coli adherence factors. By linking local land use at a national scale with the occurrence of freshwater 3GC-E. coli, we demonstrate the value of a One Health approach for understanding how human activities influence the environmental dissemination of antimicrobial resistance with implications for infectious disease risk. Antimicrobial resistance (AMR) threatens public health by making infections harder and more expensive to treat. While AMR is often studied in clinical settings, environmental pathways that spread resistant bacteria remain less understood. Using a One Health approach, we investigated how land use influences the presence of third-generation cephalosporin-resistant Enterobacterales in freshwater across New Zealand. We found that resistant Escherichia coli, including strains carrying plasmid-associated virulence factors, were most frequently detected at sites impacted by urban land use and human fecal contamination. These findings show that human activities shape the environmental distribution of clinically relevant resistance and highlight freshwater as a potential exposure pathway. By linking national-scale land-use patterns with the occurrence of resistant bacteria in the environment, this study demonstrates how integrated environmental and public health surveillance can improve our understanding of AMR dissemination and inform strategies to reduce the spread of resistant pathogens.
Free-living amoebae (FLA), such as Acanthamoeba, are protozoan parasites that take advantage of opportunities with a widespread distribution in various environmental sources, such as a wide range of water sources. The amoeba can accidentally infect individuals and cause a variety of diseases, including amoebic encephalitis and keratitis, in both immunocompetent and immune-deficient individuals. The amoeba can act as reservoirs and carriers for pathogenic microorganisms, increasing the risk of pathogenicity in humans. The objective of this research was to identify the genotypes, besides in addition to the species of the FLA, in water sources in Qazvin province using high-resolution melting analysis (HRM). A total of 44 DNA isolates from FLA, including samples from swimming pools irrigation canals, and drinking water, were analyzed for the 18SrDNA gene using HRM. The data was evaluated using Chi-square test and Fisher's exact tests. The Molecular analysis revealed that 79.5% of the isolates were of the T3 genotype, 6.9% were of the T4 genotype of Acanthamoeba, and 13.6% were identified as Protoacantamoeba bohemica species. The statistical analysis exhibited a significant difference among the contamination and water source. As water sources directly related to the public health, this study recommends paying close attention to treating water sources and utilizing new and accurate molecular methods to identify the potential pathogenic amoeba.
Batik wastewater contains high concentrations of recalcitrant hydrophobic wax, reactive dyes, and heavy metals. Conventional biological treatments are limited because single strains often cannot degrade wax effectively, whereas free bacterial consortia (FBC) are susceptible to washout. This study evaluated indigenous wax-degrading bacterial consortia immobilized on sequentially activated geothermal waste silica and optimized the carrier properties to enhance wax and organic load removal from real batik wastewater. Geothermal silica was tailored through a four-step activation sequence including water washing, hydrochloric acid activation, thermal activation, and surface functionalization to improve its physicochemical suitability as an immobilization carrier. The performance of immobilized bacterial consortia (IBC) was compared with FBC using standard indicators (oil and grease, COD, and BOD). The activated silica achieved an immobilization efficiency of 64.04%. In real batik wastewater, IBC delivered 99.32% oil and grease removal with simultaneous reductions of 56.01% in BOD and 58.20% in COD, outperforming FBC (98.96% oil and grease removal; 26.29% BOD and 47.73% COD reduction). These results demonstrate that sequentially activated geothermal silica is a low-cost, effective carrier for immobilizing indigenous consortia, enabling more stable and enhanced removal of wax and organic load in batik wastewater.
Understanding how trees balance carbon storage, hydraulic function, and growth under drought is critical for predicting forest resilience to climate change. However, little is known about the interactive roles of non-structural carbohydrates (NSC), particularly starch and soluble sugars, in coordination with wood anatomical traits and stable isotope signatures in mediating tree responses to drought stress. This study investigates the interplay between NSC, wood anatomical traits, and intrinsic water use efficiency (iWUE) in 56 European beech (Fagus sylvatica L.) trees from different crown conditions across drought and wet years in four sites in northeastern France with contrasted soil water deficit. We followed NSC (starch and soluble sugars) content in sapwood of trees each year and analyzed retrospectively tree ring width, vessel anatomy and stable isotopes (δ13C, δ18O). Results revealed that drought years significantly reduced starch content but increased soluble sugars, reflecting their role in osmotic regulation and metabolic demands. The soluble sugars to NSC ratio increased during drought, highlighting a dynamic carbon reallocation. Growth (tree basal area increment) declined in drought years, with starch accumulation in wetter years and soluble sugars prioritizing survival under stress. Soluble sugars to NSC ratio correlated positively with vessel density and theoretical specific xylem hydraulic conductivity (Kth), suggesting their involvement in hydraulic maintenance, while starch exhibited a negative relationship with Kth, indicating a trade-off between carbon storage and hydraulic efficiency. Elevated δ13C and iWUE during drought confirmed stomatal closure to conserve water, though at the cost of reduced carbon assimilation. δ18O correlated positively with soluble sugars, closely coupling carbohydrate dynamics to altered transpiration. These findings underscore how NSC dynamics, anatomical adjustments, and isotopic signals collectively mediate drought responses, offering insights into carbon-water trade-offs in temperate forests.
This paper quantifies the impact of prenatal exposure to lead in drinking water on infant health at birth by exploiting a quasi-experiment in Jackson, Mississippi. This setting provides a unique context where behavioral changes to avoid lead-contaminated water are limited due to delayed water testing and dissemination of information about lead contamination. We apply synthetic control using other US cities and Mississippi counties as donors to identify the effect of lead exposure on birth outcomes. We find that prenatal lead exposure in Jackson increased the incidence of low birth weight by approximately 1.5 percentage points, relative to a synthetic Jackson.
Harmful cyanobacterial blooms (HABs) pose serious risks to freshwater ecosystems, drinking water supplies, and public health, highlighting the need for reliable early-warning systems. This study presents a rigorously validated machine learning framework for predicting cyanobacterial alert levels under strongly imbalanced conditions using routinely measured physicochemical variables. Four gradient boosting algorithms were systematically combined with 12 resampling strategies and evaluated within a nested cross-validation framework to ensure unbiased performance assessment. Model evaluation incorporated metrics tailored to imbalanced classification, including recall, F1-score, balanced accuracy (BA), and the Matthews correlation coefficient (MCC), with particular emphasis on the detection of alert events. Results demonstrate that resampling is critical for improving minority-class detection, with SMOTE-based approaches consistently providing the most favorable balance between sensitivity and precision across algorithms. LightGBM combined with SMOTE achieved the highest recall and F1-score, together with strong BA and MCC values and low variability across folds, indicating robust generalization. XGBoost combined with SMOTE exhibited a more balanced precision-recall profile with comparable overall performance but higher variability. SHAP-based interpretability analyses revealed consistent and ecologically meaningful drivers across models, with water temperature, turbidity, and pH emerging as the most influential predictors. By restricting inputs to variables measurable in near real time using low-cost in situ sensors, the proposed framework is designed to support operationally feasible early-warning applications through frequent updates of alert-level predictions within environmental monitoring systems. Overall, the findings highlight the importance of addressing class imbalance, ensuring rigorous validation, and incorporating interpretability to support practical and operationally feasible cyanobacterial early-warning applications.
Prussian Blue is not only the oldest synthetic pigment, but also an electrochemically active material with modern technological relevance for its electrochromic properties and applications in energy storage. In this work, we study the fundamental mechanism of electron transport processes in this material, and how it varies as the material is progressively oxidized from Prussian White to Prussian Blue. Recently developed methods in spectroelectrochemical ultrafast 2D infrared spectroscopy allow us to measure the electron transfer rate within a film of Prussian Blue deposited onto the working electrode in an electrochemical cell as a function of applied bias potential. The intrinsic CN stretching modes serve as a local probe of the Fe oxidation state and as a measure for the solvation dynamics induced by water molecules incorporated into the subcells of the zeolitic lattice. We observe a fast, ps-scale electron transfer process with a rate that varies with the state of the material, revealing the intrinsic mobility of electrons decoupled from the slow diffusion of K+ ions. By correlating these observations to changes in the local structural distributions of FeIII sites, K+ ions and water molecules with the aid of a lattice model, we obtain insight into the mechanism of electron transport in this material. These results demonstrate a method for observing fast electron transfer and correlating them with nuclear motions, and provide a way to study chemical transformations at the electrochemical interface.
The globally distributed precious metals beryllium and tungsten have recently become elements of interest for environmental regulators due to their presence in mine tailings and their potential to migrate to the broader environment. The chronic toxicity of these elements to freshwater species is poorly understood, which is of particular concern in the Southwest Australia ecoregion, an area classified as a Global Biodiversity Hotspot, given the significant existing and proposed mining activities in the region. Here, the chronic toxicity of beryllium and tungsten was assessed using the recently developed Southwest Australian Toxicity Test Suite, comprising eight species local to the region. Beryllium was generally more toxic to local species than tungsten, with sensitivity based on the no (significant) effect concentrations (N(S)EC) ranging from 667-3,300 µg/L (beryllium) and 2,000-4,770 µg/L (tungsten) in moderately hard water. Species sensitivity (N(S)EC) to beryllium from most to least sensitive was cladoceran, Ceriodaphnia dubia > alga, Chlamydomonas oviformis > green hydroid, Hydra viridissima > alga, Scenedesmus sp. > alga, Chlorella sp. > cladoceran, Simocephalus exspinosus > alga, Tetradesmus obliquus > gastropod, Glyptophysa georgiana. The order of sensitivity for tungsten was different: Hydra viridissima > Chlorella sp. > Scenedesmus sp. > Tetradesmus obliquus > Glyptophysa georgiana > Ceriodaphnia dubia > Simocephalus exspinosus > Chlamydomonas oviformis. Median effect concentrations (EC50s) and 10% effect concentrations (EC10s) are also presented. This article provides chronic toxicity datasets for beryllium and tungsten to inform environmental risk assessment in the region and contribute to the knowledgebase of these globally significant toxicants.
Paracoccus marginatus is a regulated, highly invasive pest that poses a significant risk to papaya production and international trade, necessitating effective phytosanitary disinfestation measures. Hot-water treatment (HWT) is widely recognized as a residue-free alternative to chemical fumigation; however, its operational schedules require alignment between pest thermal tolerance and fruit quality. In this study, the thermal tolerance of developmental stages of P. marginatus was quantified, and candidate HWT regimes were evaluated based on thermal tolerance determined on a surrogate host (sprouting potato), while papaya physiological and sensory responses were assessed separately. Eggs exhibited the highest heat tolerance among developmental stages and were therefore used as the conservative biological endpoint for treatment optimization. Time-mortality analysis and large-scale confirmatory trials conducted on sprouting potato demonstrated that immersion at 49 °C for 22 min, or 47 °C for 81 min, achieved complete mortality of P. marginatus. Fruit quality assessments indicated that optimized HWT regimes delayed ripening, reduced decay incidence, and maintained firmness, color, and sensory acceptability during storage, whereas prolonged exposure at lower temperatures induced cumulative physiological stress. By combining pest mortality data from sprouting potato with papaya fruit tolerance limits, this study identifies candidate temperature-time parameters that may achieve phytosanitary security while preserving papaya fruit quality. The results provide a practical basis for developing heat treatment schedules consistent with the International Standards for Phytosanitary Measures. © 2026 Society of Chemical Industry.
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Signal transducer and activator of transcription 5B (STAT5B) plays a critical role in milk protein synthesis in mammals. However, its transcriptional regulatory mechanisms in buffalo, particularly in Binglangjiang buffalo, a breed characterized by high milk protein content, remain largely unclear. The study isolated and identified the functional STAT5B transcript variant in lactating buffalo mammary gland tissues. Expression analysis revealed that STAT5B was significantly upregulated in lactating buffalo mammary epithelial cells (BuMECs) compared with non-lactating BuMECs, suggesting its potential involvement in lactation regulation. Subcellular localization analysis confirmed that STAT5B was distributed in both the nucleus and cytoplasm of BuMECs, providing a structural basis for its transcriptional regulatory function. Importantly, functional experiments identified a novel positive feedback loop between ELF5 and STAT5B, through which STAT5B promoted casein synthesis in BuMECs. The findings significantly expand our understanding of STAT5B-mediated transcriptional regulation in ruminants and enrich the molecular regulatory network of milk protein synthesis in buffalo. These findings provide important theoretical support and potential molecular targets for genetic improvement of milk protein content in the buffalo dairy industry. STAT5B is critical for buffalo milk protein synthesis, while its regulatory mechanism remained unknown. The study identified a functional STAT5B variant in lactating buffalo mammary glands that promotes casein synthesis and cell proliferation via JAK2-STAT5 and mTOR pathways, and uncovered a novel ELF5-STAT5B positive feedback loop. These findings provide a theoretical basis for enhancing buffalo milk quality and improving milk nutritional value to meet consumer demands.
Mining operations with local geogenic processes and other anthropogenic activities significantly alter quality of natural water resources systems. In complex geological settings these interactions influence contaminant transport behavior leading to shifts in hydrogeochemical signatures of (sub)-surface waters. Hence, a methodological framework is crucial to coherently link these geogenic and anthropogenic signatures with contamination sources and evaluate associated health risks in mining regions. The hydrogeochemical processes were initially studied using Gibbs and Piper plots, along with mineral saturation indices to establish baseline conditions in limestone mining environments. Thereafter, Entropy Water Quality Index (EWQI) was applied to delineate contamination hotspots. Non-carcinogenic risks from potentially toxic elements (PTEs) were evaluated to validate effects of contaminated water exposure. Finally, Principal Component Analysis (PCA) was employed to distinguish natural geochemical signatures from anthropogenic inputs. The results showed that (sub)-surface water quality was controlled by geogenic processes, particularly carbonate and silicate weathering, with additional inputs from anthropogenic activities. The piper plot classified most samples into CaMgHCO3 facies (53%) reflecting dissolution of limestone and dolomite minerals. The mineral saturation indices highlighted thermodynamically favorable conditions for carbonate dissolution. EWQI values exceeding 150 indicated contamination hotspots characterized by extremely poor water quality. The health risk assessment validated these findings, with Hazard Index (HI) indicating significant non-carcinogenic risks, particularly for children. HI values exceeded the threshold of 1 in both groundwater (1.70-5.66) and surface water (1.60-17.65) samples across seasons. PCA further differentiated geogenic controls from anthropogenic sources such as mining and agriculture. This study establishes a holistic hydrogeochemical framework for quantifying both geogenic and anthropogenic processes and associated health and environmental risks in mining regions globally.
Aminobacter niigataensis MSH1 is a candidate for bioaugmentation of sand filters in drinking water treatment plants (DWTP), as it mineralizes the ubiquitous groundwater micropollutant 2,6-dichlorobenzamide (BAM). The DWTP sand filter isolate Piscinibacter sp. K169 improves BAM mineralization by MSH1 in an apparent accidental mutual cooperation, and co-inoculation of the organism was proposed to assist bioaugmentation with MSH1. In this study, we questioned whether this accidental mutual positive interaction extends to four other pesticide catabolic bacterial strains of the same or a different genus of MSH1, and examined the longevity of the cooperation. Negative interactions were never observed in either direction. As observed for BAM mineralization by MSH1, K169 stimulated BAM mineralization by A. niigataensis LG1 and 2,4-D mineralization by Cupriavidus pinatubonensis JMP134 without affecting the cell density of the catabolic strains. Linuron mineralization by Variovorax sp. SRS16 and carbofuran mineralization by Novosphingobium sp. KN65.2 were not affected. In the other direction, growth of K169 was stimulated by all pesticide catabolic strains except JMP134, indicating a common underlying mechanism. After 2 weeks, the beneficial effects of K169 on MSH1, LG1, and JMP134 functionality diminished or even reversed, likely because of organic carbon depletion. In contrast, cell densities of K169 in all dual-species systems remained higher than in the K169 monoculture system. This study extends our knowledge on accidental interactions and the beneficial effect of a sand filter isolate toward other pesticide degraders, opening doors for Piscinibacter sp. K169-assisted bioaugmentation of other/multiple pesticide degraders in DWTPs. Sand‑filter bioaugmentation with the BAM‑catabolic Aminobacter niigataensis MSH1 represents an advanced strategy for removing BAM from groundwater in drinking water treatment; however, prior studies indicate that efficacy lasts only for 1-2 weeks. Piscinibacter sp. K169, an isolate from drinking‑water sand filters, supports mineralization of BAM by MSH1 through accidental mutual cooperation, and co‑inoculation with K169 was suggested as an innovation to improve MSH1 bioaugmentation. We show that K169 promotes mineralization of OMPs by other bacteria and, hence, that the K169-degrader cooperation can be extended to support removal of other or even multiple OMPs. Benefits declined over time, likely due to nutrient depletion, making nutrient management a requirement for maintaining the cooperation. To the best of our knowledge, this is the first study to examine specificity in accidental microbial cooperation, especially in a bioaugmentation context of water treatment. It is relevant both to a fundamental understanding of accidental microbial interactions and to applications in water treatment.
Water scarcity in arid and desert regions critically threatens agricultural sustainability. We report a cellulose-based superabsorbent hydrogel achieving an ultrahigh water absorption ratio exceeding 20,000 wt %, the highest among all reported cellulose hydrogel systems. It retains ∼82% of its swelling capacity after five wet-dry cycles, demonstrating outstanding recyclability. In desert sand at 40 °C, just 3 wt % hydrogel sustained over 10% residual moisture for 48 h without irrigation. Swelling followed a quasi-second-order model with dual-phase diffusion, enabling rapid hydration and controlled water release. Hydrogel-amended sand markedly enhanced Triticum aestivum seedling drought resilience, extending wilting time by 5-7 days. Biodegradable and recyclable, this hydrogel simultaneously boosts soil moisture retention, respiration rate, microbial activity, and crop stress tolerance, offering a powerful, sustainable strategy for agriculture and ecological restoration in water-limited regions.
Water is indispensable to life and plays a central role in biological functions. In this study, glycopolymers with distinct backbones (acrylamide or acrylate) and linker lengths (methylene or ethylene) were synthesized via RAFT polymerization to investigate their hydration states. Thermal analysis revealed that glycopolymers with an acrylamide backbone retained more hydration water than those with acrylate backbones. This trend was consistently supported by terahertz spectroscopy and molecular dynamics simulations. In addition, the amount of hydration water increased with increasing linker length. Hemagglutination inhibition assays showed that acrylate-type glycopolymers exhibited markedly higher binding affinity for concanavalin A than their acrylamide-type counterparts across all degrees of polymerization. Importantly, these results reveal a clear inverse correlation between the amount of hydration water and binding affinity, indicating that excessive hydration hinders lectin recognition.
Urban rivers supplying drinking water face mounting pollution and AMR threats. We combined shotgun metagenomics with physicochemical analysis to investigate microbial community and resistome dynamics in Bangladesh's Shitalakshya River, a drinking water source under increasing pollution pressure, during early and peak dry seasons. Peak dry season water quality deteriorated markedly, characterized by hypoxia and elevated nutrient and organic carbon levels, which drove pronounced restructuring of the river microbiome. A distinct shift occurred from Myroides dominance toward a more diverse assemblage enriched in pollution-tolerant and opportunistic genera, notably Comamonas, Brevundimonas, Tissierella, and Aeromonas. Metagenomic profiling revealed a diverse resistome encompassing antibiotic, metal, and biocide resistance genes. Although overall antibiotic resistance gene abundance declined slightly, metal resistance genes increased more than twofold, with strong enrichment of mercury resistance determinants such as merA. Concurrent increases in multidrug efflux pump genes suggested potential co-selection driven by metal and chemical stressors. These findings indicate that dry-season pollutant concentration reshapes both microbial communities and resistance profiles through non-antibiotic selective pressures. Despite limited sampling, this study provides a baseline metagenomic snapshot of antimicrobial resistance dynamics in a climate-stressed urban river system, offering vital insights for pollution abatement and the safeguarding of drinking water safety.
Variations in ionic profiles and chemical characteristics viz. aerosol liquid water content (ALWC) and in situ pH of fine aerosol plausibly caused by crop residue burning (CRB) over the North-Western Indo-Gangetic Plain were studied. Ambient PM2.5 samples were collected and criteria air pollutants were obtained for Amritsar, Punjab, from September to December, covering pre-CRB and CRB phases. These samples were analyzed for water-soluble ionic species. Further, Extended Aerosol Inorganics Model (E-AIM) model II was used to calculate ALWC and in situ pH. PM2.5 concentrations increased significantly from 48.5 ± 22.6 μg m-3 (pre-CRB) to 77.6 ± 24.3 μg m-3 during CRB, showing a 60% increase during the CRB phase. Scaling analysis revealed that while gaseous pollutants (NO2, SO2) were primarily amplified by meteorological trapping, the surge in PM2.5 was driven by a 2.7-fold increase, from 23 ± 36 (pre-CRB) to 63 ± 88 (CRB), in fire detection counts. Chemical characterization of water-soluble ionic species showed a doubling of the biomass burning marker K+ from 746 ng m-3 to 1367 ng m-3 and a significant rise in secondary inorganic aerosols, particularly nitrate (NO3-), which increased from 198 ng m-3 to 2439 ng m-3. Charge balance analysis revealed an alkaline aerosol nature, with neutralization pathways shifting from terrigenous dust (Ca2+, Mg2+) to anthropogenic (NH4+ + K+) during the CRB phase. Interestingly, the median value of ALWC increased significantly (p = 0.002) from 6.18 μg m-3 (pre-CRB) to 16.48 μg m-3 (CRB). However, no significant variation in in situ pH was observed between pre-CRB and during CRB periods. This could be attributed to internal changes observed in the ionic profiles of fine aerosol due to CRB emissions.
Developing low-cost, corrosion-resistant catalytic electrodes for the oxygen evolution reaction (OER) is essential for efficient and durable hydrogen production via anion exchange membrane water electrolysis (AEMWE). Herein, we report a polydopamine (PDA)-coated Fe,Cr codoped NiS2 self-supporting electrode (PDA-Fe,Cr-NiS2@NF). The nitrogen-rich functional groups of PDA establish robust M-N coordination bonds with active metal centers, thereby suppressing metal dissolution during anodic reconstruction. In parallel, the conductive PDA layer regulates interfacial electron redistribution and optimizes the hydrogen-bond network of interfacial water, lowering the OER activation energy. Its conformal protective layer further enhances catalyst stability. The optimized electrode delivers an OER overpotential of only 247 mV at 1 A cm-2. When integrated as the anode with a PtNiC cathode in an AEMWE cell, the system reaches a current density of 1 A cm-2 at only 1.737 V at 70 °C and operates stably for 1000 h, with a voltage decay rate of only 0.1 mV h-1, an electrolysis efficiency of 71.96%, and an energy consumption of 4.157 kWh Nm3- H2. This work establishes a viable coordination-protection strategy for constructing durable, high-performance OER electrodes for industrial-scale water electrolysis.
Double emulsions of water-in-oil-in-water (w1/o/w2) are critical for encapsulation and controlled release in microfluidic applications. In this work, double emulsion droplets were produced via a two-step flow-focusing process in a microchannel. A low-viscosity silicone oil (4.6 mPa s) was used as the oil phase, while the aqueous phase consisted of 48 wt% water and 52 wt% glycerol. Sodium dodecyl sulfate (SDS) was added at concentrations 0.2, 0.5, 1, and 2 times its critical micelle concentration (CMC = 11 mM) to systematically vary the interfacial tension. Three distinct formation regimes, namely drop-in-drop, drop-in-plug, and drop-in-thread, were identified under varying flow rate ratios and interfacial tensions. A semi-empirical model was developed to predict double droplet size in the drop-in-drop regime, which has significant practical relevance. For conditions with C/CMC ≥ 1, where interfacial tension is assumed to have reached equilibrium, good agreement with the experimental data was obtained, with mean absolute percentage errors (MAPE) of 8.16% for the core droplets and 9.54% for the double droplets. For lower surfactant concentrations, incorporating dynamic interfacial tension gave a MAPE of 8.17% for double droplet size prediction. These results provide a quantitative framework for droplet size prediction and offer operating guidance for the controlled generation of encapsulated droplets in microfluidic systems.
To identify intersectional vulnerability profiles among 5-year-old children with untreated dental caries and to analyze associated social inequalities in Brazil. This is a population-based, cross-sectional study using data from the National Survey of Oral Health (SB Brasil 2023). Five-year-old children examined in the survey were included. The variables used to identify profiles were: race/skin color, household income, maternal level of education, beneficiaries of social welfare programs, and region of residence. For profile comparison, the variables "last dental appointment" and "presence of piped water at home" were used. Descriptive, bivariate (χ²), Two-Step Cluster, and binary and multinomial logistic regression analyses were performed. A total of 7,185 children were analyzed, of whom 44.8% presented untreated dental caries. Higher prevalence values were observed among children with low maternal education (51.9%), Black (49.9%) and Indigenous (75.0%), low income (54.1%), living in the North (56.3%) region, and beneficiaries of social welfare programs (53.0%) (p<0.001). Three profiles were identified: Profile A (boys, Black, from the Northeast, low income, and high dependence on social welfare programs) showed lower probability of dental appointment in the past 2 years (OR 0.59; 95%CI 0.48-0.73; p<0.001); Profile B (boys, White, from the Northeast, low income, and beneficiaries of social welfare programs) showed worse conditions regarding the presence of piped water at home (OR 0.38; 95%CI 0.19-0.76; p=0.006); and Profile C (girls, Black, from the North, higher income, and lower dependence on social welfare programs) concentrated the best conditions for dental appointment and piped water (p<0.001). Untreated dental caries among 5-year-old children reflects structural inequities combining racial, socioeconomic, territorial, and income-related inequalities.