Potential Measurements Research Articles

Looking outside the box with a pathology aware AI approach for analyzing OCT retinal images in Stargardt disease

Stargardt disease type 1 (STGD1) is a genetic disorder that leads to progressive vision loss, with no approved treatments currently available. The development of effective therapies faces the challenge of identifying appropriate outcome measures that accurately reflect treatment benefits. Optical Coherence Tomography (OCT) provides high-resolution retinal images, serving as a valuable tool for deriving potential outcome measures, such as retinal thickness. However, automated segmentation of OCT images, particularly in regions disrupted by degeneration, remains complex. In this study, we propose a deep learning-based approach that incorporates a pathology-aware loss function to segment retinal sublayers in OCT images from patients with STGD1. This method targets relatively unaffected regions for sublayer segmentation, ensuring accurate boundary delineation in areas with minimal disruption. In severely affected regions, identified by a box detection model, the total retina is segmented as a single layer to avoid errors. Our model significantly outperforms standard models, achieving an average Dice coefficient of for total retina and for retinal sublayers. The most substantial improvement was in the segmentation of the photoreceptor inner segment, with Dice coefficient increasing by . This approach provides a balance between granularity and reliability, making it suitable for clinical application in tracking disease progression and evaluating therapeutic efficacy.

Revealing Light-Magnetism Coupling via Anomalous Hall Effect and Magneto-Photoresponse in Proximity-Coupled CrSBr/Graphene Heterostructures.

The interplay between light and magnetism sparks groundbreaking concepts for the next-generation versatile spintronic and nanoelectronic devices. However, direct measurements of light-magnetism coupling remain challenging due to the intrinsic difficulties in characterizing these properties simultaneously. Herein, via harnessing magnetic proximity and anomalous Hall effect (AHE), we report the effective modification of magnetism in the graphene/CrSBr heterostructure by an unpolarized 405 nm light. The emergence of magnetism in graphene is ascribed to the proximity effect, which arises from its coupling with the neighboring CrSBr. The photoinduced charge transfer doping into graphene exerts a precise tune over the Fermi level (EF), facilitating the optical control of carrier density and mobility. This operation engenders an adjustable anomalous Hall resistance and magnetoresistance congruent with the Fermi level tuning, further verified by surface potential measurements. In parallel, high-performance magneto-photoresponse has been realized, which is believed to result from spin polarization-enhanced photoinduced charge separation. Our study offers insights into the interplay between light and magnetism, showcasing the potential of 2D proximity-coupled heterostructures in opto-spintronics.

The Aberrant Behavior Checklist for Fragile X Syndrome: A Qualitative Clinician Evaluation of Content Validity.

Objective: The current intense period of drug development for fragile X syndrome (FXS) and other neurodevelopmental disorders (NDDs) indications has highlighted the importance of behavioral outcome measures with strong psychometric properties and specifically content validity. The Aberrant Behavior Checklist-Community Edition (ABC-C), which has successfully been applied to autism spectrum disorder drug trials, has been revised for FXS (ABCFX) and is widely used for both clinical and research purposes. Despite its strong psychometric validation, the ABCFX and its parent measure have not been subjected to qualitative content validity evaluations. The present study intended to fill this gap. Methods: Using two surveys administered sequentially and developed with guidance and review from the Food and Drug Administration (FDA), we asked 10 clinicians experienced in FXS and related NDDs to determine the adequacy of the ABCFX for assessing its behavioral constructs, its relevance to FXS, and its potential for detecting response to interventions. Various descriptive statistic parameters and ad hoc metrics were used to analyze categorical and Likert-like scale responses. Results: Experts considered that most items and all six ABCFX subscales indeed evaluated their explicit or implicit behavioral constructs. However, item and subscale specificity were relatively low (∼25%-30%). Relevance of items of the Hyperactivity subscale was relatively high while low for many items of the Socially Unresponsive/Lethargic subscale. These items were also considered of low responsiveness potential. Irritability, Hyperactivity, Stereotypy, and Social Avoidance were the subscales with the strongest profiles, although the experts estimated that Stereotypy items may not be that responsive to treatment. A novel Anxiety construct, representing mainly recently reported observable behaviors, contributed mainly by Irritability items, emerged as a potential measure. Conclusions: The present study demonstrated the overall adequacy of the ABCFX for its behavioral constructs, its relevance to FXS, and its potential for detecting response to treatment. It also showed that anxiety, a distinctive feature of FXS and other genetic NDDs, can also be measured by the ABCFX. These findings can help with the implementation and interpretation of the ABCFX, as well as with potential improvements to the measure in FXS and other NDDs.

Synthesis and Bioactivity of Selenium Nanoparticles from Tussilago farfara L Polysaccharides: Antioxidant Properties and MCF-7 Cell Inhibition.

The present study reports the synthesis of a selenium nanocomplex (Se-TFPs) using purified polysaccharides from Tussilago farfara L (coltsfoot). It evaluates its structural characteristics, physicochemical properties, and inhibitory effects of Michigan Cancer Foundation-7 (MCF-7) breast cancer cells. The influence of processing conditions on nanoparticle size and stability at 25 °C was assessed using particle size and zeta potential measurements. The Se-TFPs were synthesized by optimizing the processing conditions via response surface methodology, yielding nanoparticles with a selenium (Se)-to-polysaccharide mass ratio of 1:13.5, a Se-to-ascorbic acid molar ratio of 1:4.5, a selenite concentration of 10.7 mM, and a reaction time of 4.4 h. The resulting Se-TFPs had an average particle size of 107.2 nm and a zeta potential of -35.1 mV. Structural and physicochemical analyses confirmed successful nanoparticle formation. Compared to TFPs, Se-TFPs exhibited significantly enhanced scavenging activity against 2,2-Diphenyl-1-picrylhydrazyl (DPPH), 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), hydroxyl radicals, and superoxide anion radicals. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, flow cytometry, and cell cycle apoptosis analysis revealed that Se-TFPs effectively inhibited MCF-7 cell proliferation at the S phase, with an IC50 value of 119.62 μg/mL.

Consequences of multiple axions in theories with dark Yang-Mills groups

General consistency requirements of quantum gravity suggest the existence of one axion per Yang-Mills group (YM) [a gauged special unitary group SU(n)]. In this work we take this requirement seriously and consider theories with dark Yang-Mills sectors and investigate general phenomenological implications of these axions. We carry out computations for two simple models, namely a pure Yang-Mills sector and N exact Standard Model (SM) copies. For the former, the misalignment mechanism results in a minimal dark confinement scale Λconf≳1 eV if the dark sector axion is supposed to make up the dark matter. For the latter, the misalignment mechanism without fine-tuning of the initial misalignment angle places an upper bound on N below the species bound. When the Peccei-Quinn symmetries are broken during inflation, the collective isocurvature fluctuations do not necessarily tighten the bound on the inflationary Hubble scale arising from a single axion. We also point out that axion stars collectively made from axions of different dark sectors with a suppressed mass spectrum are not possible. Lastly, for the two models at hand, intersector interaction through axion kinetic mixing leads to the existence of two distinct axion states. For a single dark YM sector, the upper bound Λconf≲1012 GeV emerges from the stability requirement of the dark sector axion. For N exact SM copies, the mass and photon coupling of the second state is completely determined after a potential measurement of the analogous parameters of the first axion. Published by the American Physical Society 2025

Preparation, characterization, and pesticide adsorption capacity of chitosan-magnetic graphene oxide nanoparticles with toxicological studies.

This study investigated magnetic graphene oxide nanoparticles (MGO-NPs) and functionalized with chitosan (CS-MGO-NPs) for removing florasulam, metalaxyl, and thiamethoxam pesticides from water. A comprehensive characterization employing Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), zeta potential measurements, XRD analysis, and surface area/porosity determinations confirmed the successful synthesis of the composites with the desired properties. Factorial experimental design was applied to identify the most significant factors of pesticide concentration, adsorbent amount, temperature, pH, agitation time, and ionic strength on the efficiency of removal of tested pesticides from water samples. CS-MGO-NPs exhibited superior removal efficiencies for all three pesticides compared to MGO-NPs. They achieved high removal rates for florasulam (average 92.94%) and metalaxyl (average 88.95%), while demonstrated moderate effectiveness against thiamethoxam (average 64.04%). Different kinetic and isotherm models described how well the nanoparticles adsorbed each pesticide. According to these models, the pseudo-first-order kinetic model interpreted well the adsorption of florasulam, and thiamethoxam onto CS-GO-NPs. While the pseudo-second-order kinetic model interpreted well the adsorption of metalaxyl. The Freundlich isotherm model gave the best fit with florasulam onto CS-GO-NPs. While the Langmuir isotherm model gave the best fit with metalaxyl and thiamethoxam. Finally, the toxicological studies of CS-MGO-NPs in rats were performed, and it was found negative effects at high doses, suggesting caution is needed for practical applications. Overall, this study shows promise for CS-MGO-NPs in water purification, but safety needs further investigation.

Age-related immune response disparities between adults and children with severe COVID-19: a case–control study in China

BackgroundElucidation of immune response differences is critical for uncovering underlying mechanisms and developing potential intervention measures among adults and children with COVID-19.MethodsIn this retrospective study, we analyzed serum biochemical markers and cytokine profiles among adults and children with COVID-19 in the First People’s Hospital of Chenzhou in Hunan, China from 1 December 2022 to 13 February 2023. A case–control study was conducted using propensity score matching (PSM) to mitigate possible confounding factors.ResultsThe significant differences observed included lymphocyte exhaustion, an increased neutrophil-to-lymphocyte (NEU/LYM) ratio, high levels of C-reactive protein (CRP), and a cytokine storm, characterized by high levels of Th1 proinflammatory cytokines, including interleukin 1β (IL-1β), IL-6, IL-8, interferon type I (IFN-γ), and tumor necrosis factor (TNF-α) in the lung among severe adult COVID-19 patients. Additionally, systemic immune responses were observed in children with COVID-19.ConclusionSignificant differences in immune responses between adults and children with COVID-19 highlight the different mechanisms and potential intervention measures of COVID-19.

Development of a Dermal Nanoemulsion with Antioxidants Derived from Rice Residues Using an HLD Theory Approach

Agricultural waste, such as rice straw, has become increasingly valuable as biocomposites in various industries. For cosmetic and pharmaceutical sectors, these biocomposites have improved active substance incorporation and waste reduction, which is pivotal for mitigating environmental impact. This study reports the encapsulation of a protein derivative derived from rice straw within a nanoemulsion for skin care applications, emphasizing stability and efficacy. Protein hydrolysates were produced by extracting proteins in an alkaline medium, followed by precipitation at the isoelectric point. The hydrolysates were enzymatically treated with Alcalase® at 80 °C and pH 10 for 45 min to generate antioxidant-rich formulations. Utilizing Hydrophilic-Lipophilic Deviation (HLD) theory, oil-in-water (O/W) emulsions were formulated by adjusting variables to achieve an HLD near zero. Sunflower oil and surfactants were combined, stirred at 70 °C, and homogenized using a rotor–stator. The final formulation's stability and permeability were evaluated through fluorescence microscopy, particle size analysis, zeta potential measurements, and accelerated stability assays. Nanoemulsion ENE37 showed high stability with 47.25 nm size, PDI 0.21, and excellent dispersion, maintaining integrity without phase separation. Hydrolyzed protein into ENE37 (NE37-HP) improved stability, increasing zeta potential and preventing aggregation while maintaining structure without phase inversion. NE37-HP exhibited shear-thinning behavior and good diffusion capacity, achieving 20.14 μg/cm2.h. The HLD theory and ternary diagrams are valuable methodological tools for formulating stable nanoscale emulsions. Additionally, this dosage form, containing protein hydrolysates derived from rice straw, demonstrated potential for adequate dermal absorption in humans.Graphical

Retracing the Cold Plasma Dispersion Law in Pulsar B0329+54: New Insights into Frequency-dependent Dispersion Measures

Abstract Multiple studies have investigated potential frequency-dependent dispersion measures (DMs) in PSR B0329+54, with sensitivities at levels of 10−3 pc cm−3 or higher, using frequencies below 1 GHz. Utilizing the extensive bandwidth of the upgraded Giant Metrewave Radio Telescope, we conducted simultaneous observations of this pulsar across a frequency range of 300–1460 MHz. Our observations reveal a distinct point in the pulse profile of PSR B0329+54 that appears to align remarkably well with the cold-plasma dispersion law, resulting in a unique measured DM across the entire frequency range. In contrast, using times of arrival from widely adopted pulsar timing techniques (e.g., FFTFIT) leads to frequency-dependent DMs. We investigated the potential causes of these frequency-dependent DMs in this pulsar and their relationship with the underlying magnetic field geometry corresponding to the radio emission. Our study reveals that all frequencies in the range 300–1460 MHz originate from a region no larger than 204 km, and the dipolar magnetic-field geometry model indicates that the emission region is centered at ~800 km from the star. This is the tightest constraint on the size of the emission region reported so far for PSR B0329+54 at the given frequencies, and it is at least 5 times more stringent than the existing emission height constraints based on the dipolar geometry model.

PRG4CNN: A Probabilistic Model Checking-Driven Robustness Guarantee Framework for CNNs

As an important kind of DNN (deep neural network), CNN (convolutional neural network) has made remarkable progress and been widely used in the vision and decision-making of autonomous robots. Nonetheless, in many scenarios, even a minor perturbation in input for CNNs may lead to serious errors, which means CNNs lack robustness. Formal verification is an effective method to guarantee the robustness of CNNs. Existing works predominantly concentrate on local robustness verification, which requires considerable time and space. Probabilistic robustness quantifies the robustness of CNNs, which is a practical mode of potential measurement. The state-of-the-art of probabilistic robustness verification is a test-driven approach, which is used to manually decide whether a DNN satisfies the probabilistic robustness and does not involve robustness repair. Robustness repair can improve the robustness of CNNs further. To address this issue, we propose a probabilistic model checking-driven robustness guarantee framework for CNNs, i.e., PRG4CNN. This is the first automated and complete framework for guaranteeing the probabilistic robustness of CNNs. It comprises four steps, as follows: (1) modeling a CNN as an MDP (Markov decision processes) by model learning, (2) specifying the probabilistic robustness of the CNN via the PCTL (Probabilistic Computational Tree Logic) formula, (3) verifying the probabilistic robustness with a probabilistic model checker, and (4) probabilistic robustness repair by counterexample-guided sensitivity analysis, if probabilistic robustness does not hold on the CNN. We here conduct experiments on various scales of CNNs trained on the handwriting dataset MNIST, and demonstrate the effectiveness of PRG4CNN.

Towards sustainable microplastic cleanup: Al/Fe ionotropic chitosan hydrogels for efficient PET removal.

Chitosan (CHI) was modified with iron and aluminum salts to create ionotropic beads, Fe-CHI and Al-CHI, for the removal of polyethylene terephthalate microplastics (PET-MP) from water. Infrared spectroscopy revealed reduced hydrogen bonding associated with N-H vibration of CHI (3500-3100cm-1) due to the interaction with the metal ions, and absorption peaks between 500 and 916cm⁻1 predominantly due to metal-oxygen stretching vibrations. The swelling behavior of the beads increased with temperature but decreased as pH and metal doping concentration increased. Conductivity and PET-MP removal efficiency improved with higher metal ion concentrations, with Al-CHI exhibiting greater swelling and conductivity compared to Fe-CHI. The highest efficiency for MP remediation was recorded at low pH levels. MP adsorption decreased with rising temperatures and varied with pH changes due to protonation and deprotonation reactions of CHI, along with the various cationic and anionic species formed by the metals. At pH 7, MP removal by Fe-CHI beads declined as the doping concentration increased, attributed to specific Fe species that emerged at this pH. The zeta potential measurements showed that both the beads and the MP were in an unstable range at low pH but shifted towards stability at higher pH levels. Re-adsorption efficiencies exceeded 70% for both low and high-doped Fe-CHI and Al-CHI beads when tested with ~ 40 MP/mL of MP suspension over three different cycles. Overall, the use of ionotropic CHI beads offers a promising, eco-friendly method for effectively reducing PET-MPs in water.

Development, Characterization, and Antimicrobial Evaluation of Hybrid Nanoparticles (HNPs) Based on Phospholipids, Cholesterol, Colistin, and Chitosan Against Multidrug-Resistant Gram-Negative Bacteria

Background: Colistin, a lipopeptide antibiotic usually used as a last resort against multidrug-resistant bacterial strains, has also begun to address the challenge of antimicrobial resistance. Objective: this study evaluates whether hybrid nanoparticles (HNPs) composed of Phospholipon® 90G, cholesterol, and colistin can enhance its effectiveness against resistant clinical isolates of Klebsiella pneumoniae, a clinically significant Gram-negative bacterium. Methods: HNPs were developed using the ethanol injection method and coated with chitosan through a layer-by-layer technique. HNP characterization included measurements of particle size, polydispersity index (PDI), and zeta potential, along with thermal (DSC) and spectrophotometric (FT-IR) analyses. Ultrafiltration and ATR-FTIR were employed to assess colistin’s association and release efficiencies. The biological evaluation followed CLSI guidelines. Results: uncoated hybrid nanoparticles (U-HNP) and chitosan-coated hybrid nanoparticles (Ch-HNP) described monodisperse populations, with respective PDI values of ~0.124 and ~0.150, Z-averages of ~249 nm and ~250 nm, and zeta potential values of +17 mV and +20 mV. Colistin’s association and release efficiencies were approximately 79% and 10%, respectively. Regarding antimicrobial activity, results showed that colistin as part of HNPs is poorly effective against this microorganism. However, in the most resistant strain, colistin activity increased slightly when the HNP was coated with chitosan. Conclusions: HNPs described high stability against disaggregation, limiting the colistin release and, therefore, affecting antimicrobial performance.

Mitochondrial ROS modulate presynaptic plasticity in the drosophila neuromuscular junction.

The elevated emission of reactive oxygen species (ROS) from presynaptic mitochondria is well-documented in several inflammatory and neurodegenerative diseases. However, the potential role of mitochondrial ROS in presynaptic function and plasticity remains largely understudied beyond the context of disease. Here, we investigated this potential ROS role in presynaptic function and short-term plasticity by combining optogenetics, whole cell electrophysiological recordings, and live confocal imaging using a well-established protocol for induction and measurement of synaptic potentiation in Drosophila melanogaster neuromuscular junctions (NMJ). Optogenetic induction of ROS emission from presynaptic motorneuron mitochondria expressing mitokiller red (mK) resulted in synaptic potentiation, evidenced by an increase in the frequency of spontaneous mini excitatory junction potentials. Notably, this effect was not observed in flies co-expressing catalase, a cytosolic hydrogen peroxide (H2O2) scavenging enzyme. Moreover, the increase in electrical activity did not coincide with synaptic structural changes. The absence of Wnt1/Wg release from synaptic boutons suggested involvement of alternative or non-canonical signaling pathway(s). However, in existing boutons we observed an increase in the active zone (AZ) marker Brp/Erc1, which serves as docking site for the neurotransmitter vesicle release pool. We propose the involvement of putative redox switches in AZ components as the molecular target of mitochondrial H2O2. These findings establish a novel framework for understanding the signaling role of mROS in presynaptic structural and functional plasticity, providing insights into redox-based mechanisms of neuronal communication.

Ultrasound assisted complexation of soybean peptide aggregates and soluble soybean polysaccharide: pH optimization, structure characterization, and emulsifying behavior.

This study aims to enhance the emulsifying properties of soybean peptide aggregates (SPA) by preparing SPA-soluble soybean polysaccharide (SSPS) composite particles at the assistance of ultrasound technique. The optimal pH for SPA and SSPS complexation was determined by measuring the charge and particle size of the composites. The effects of ultrasound power and duration on the physicochemical properties of the composite particles were assessed through measurements of particle size, zeta potential, contact angle, FTIR, and SEM. The influence of ultrasound duration on the emulsifying properties of the composite particles was evaluated by particle size, zeta potential, microstructure, rheology, and in vitro digestibility. The optimal pH for SPA and SSPS complexation was determined to be 4.0. Zeta potential and FTIR analyses indicated that ultrasound enhanced the electrostatic interactions and hydrogen bonding between SPA and SSPS. Emulsions stabilized with ultrasonicated composite particles exhibited reduced particle sizes, increased viscosity, improved viscoelastic properties, and better in vitro digestibility. The results suggest that moderate ultrasound treatment can strengthen the interactions between SPA and SSPS, thereby enhancing their emulsifying properties. This study offers valuable insights into enhancing the emulsifying performance of highly hydrophobic protein particles.

Applying Shapley Effect for Sensitivity Analysis During Reactor Transient

Sensitivity analysis is a critical tool in reactor safety assessments, as it evaluates the impact of uncertainties in input parameters, identifies key factors, and highlights potential safety risks and measures. Conventional sensitivity methods, such as Spearman, Pearson, or Kendall, while straightforward, are typically limited to linear relationships and independent input parameters. Shapley values offer a more advanced, model-agnostic approach to sensitivity analysis, making them particularly valuable in scenarios with dependent parameters or nonlinear systems. This study not only applies variance-based sensitivity methods, including Sobol indices and Shapley values, but also introduces the development of a reduced-order model (ROM) based on deep neural networks (DNNs) combined with Shapley values for time-dependent reactor simulations. This approach addresses the computational challenges of traditional methods, especially in cases involving correlated parameters, providing a more efficient and accurate sensitivity analysis. Sensitivity indices are calculated for the TWIGL benchmark, with two-group cross sections as the input parameters and core power during the ramp reactivity insertion transient as the output. The results demonstrate that Shapley values, combined with the DNN-based ROM, yield robust, accurate, and physically meaningful indices, especially in models with dependent parameters where Sobol indices may lead to over- or underestimation and might even result in negative indices. This highlights the advantages of Shapley values for comprehensive and reliable sensitivity analyses in complex reactor simulations.

Elucidating the mechanism of phthalates induced osteoporosis through network toxicology and molecular docking.

This study investigated the effects of plasticizers (phthalates) on the pathogenesis of osteoporosis (OP) and the associated molecular mechanisms, especially the interaction of plasticizers with key pathways. We performed differential expression analysis of different datasets by machine learning to identify target genes associated with OP. And, we also investigated the binding of plasticizers to target proteins using network toxicology and molecular docking techniques. A total of 29 genes are potential targets associated with plasticizer-induced OP. Subsequently, machine learning analysis identified six core target genes as key genes for plasticizer-induced OP. Among them, the up-regulated genes were CKM and SOAT2, and the down-regulated genes were TACR3, SGK1, ERAP2, and MMP12 (P＜0.05). Molecular docking revealed the specific binding effect between plasticizers and target proteins. This study demonstrates that plasticizers may influence the pathogenesis of OP by targeting specific genes and pathways. And the molecular docking simulations indicate a distinct binding specificity between plasticizers and target proteins. These results provide a foundation for further investigation into the mechanisms by which plasticizers affect bone health. Future research should focus on the dose-response relationship between plasticizer exposure and the risk of OP, and explore potential intervention measures to mitigate the adverse effects of plasticizers on bone health.

The Winner and still champion: Nodule volume doubling times.

There have been enormous advances in the approach to assessing malignancy status of indeterminate pulmonary nodules including risk models, image based biomarkers and numerous types of biologic and molecular markers. All of these have the advantage of guiding further workup once the nodule is identified. The traditional method, especially for smaller nodules relies primarily on assessing whether a nodule changes in size over time and is a feature in virtually every management protocol for both screen detected as well as incidentally detected nodules. Here, the potential downside is that during the waiting period for obtaining a second scan to assess for growth prognosis changes. However, there must be enough of a time delay to overcome potential measurement error. These two features must be balanced for optimal use of this approach. The alternative approaches do not have this inherent delay, however, their usefulness is a balance between the improvement in prognosis by not having any delays versus their potential to produce false positive and false negative results. Currently nodule volumetric approaches, especially for small nodules remains the method of choice for evaluation.

Development and characterization of bael fruit gum-pectin hydrogel for enhanced antimicrobial activity.

Natural polymers are crucial for developing sustainable biomedical solutions, as their bioactivity, biocompatibility, and biodegradability make them superior alternatives to synthetic materials. The objective of the study is to develop and characterize a chemically modified bael fruit gum (BFG) and pectin hydrogel to enhance antimicrobial activity. Due to BFG's anionic nature, it was chemically modified to introduce cationic groups, facilitating cross-linking with pectin. Physicochemical characterization of BFG and pectin was conducted using FTIR and DSC, which confirmed functional groups and thermal stability, respectively. Hydrogel optimization was achieved through Central Composite Design (CCD). Rheological evaluations indicated shear-thinning behavior with a viscosity reduction under high shear stress, reflecting thixotropic properties. The hydrogel exhibited satisfactory erosion and swelling within 24h, suggesting controlled release. Zeta potential measurements confirmed the hydrogel's stability, attributed to its negative surface charge. SEM revealed a porous structure, aiding in drug encapsulation and release. Antimicrobial testing showed synergistic antimicrobial effects with inhibition zones of 1.4cm and 1.5cm against Staphylococcus aureus and Escherichia coli, respectively. Stability studies demonstrated robustness over time. Overall, this study highlights the potential of natural polymer-based hydrogels as sustainable alternatives to synthetic polymers in pharmaceutical and biomedical fields, offering safer, environmentally friendly solutions.

Influence of synergistic effect of polyacrylamide and surfactant on dewatering performance of flotation clean coal

ABSTRACT The moisture content of flotation clean coal products is a critical factor influencing their calorific value, making dewatering research vital for the efficient utilization of coal. In this study, cationic polyacrylamide (CPAM) was employed as a high molecular weight flocculant and filter aid to investigate the mechanisms by which the anionic sodium dodecyl sulfate (SDS), cationic dodecyltrimethylammonium bromide (DTAB), and nonionic polyoxyethylene lauryl ether (Brij L23) affect the dewatering of flotation clean coal. The influence of these surfactants on the dewatering performance of flotation clean coal in conjunction with CPAM was examined through filter aid experiments, density functional theory, zeta potential measurements, agglomeration of flotation clean coal particles, and Nuclear Magnetic Resonance (NMR) analysis. The results indicated that DTAB and SDS exhibited a larger positive electrostatic potential compared to Brij L23, demonstrating stronger electrostatic adsorption on the molecules of flotation clean coal. However, the -OSO3 groups in SDS interacted more strongly with the molecules of flotation clean coal than the tertiary amine groups in DTAB. The ether and hydroxyl groups in Brij L23 interacted weakly with the molecules of flotation clean coal. The surfactants increased the compactness and structural complexity between particles within the flocs, leading to an increase in the fractal dimension of the flocs. Additionally, the surfactants enlarged the pores within the filter cake of flotation clean coal, which was beneficial for the removal of moisture.

Phosphorus release under short-term submergence of pasture soils in critical source areas.

Critical source areas (CSAs) can act as a source of phosphorus (P) in surface waters by releasing soil P to porewater during frequent rainfall events. The extent of P release under short-term, frequent submergence has not been systematically studied in CSAs in New Zealand. A study was conducted to explore the potential of three contrasting dairy and sheep/beef farm soils (Recent, Pallic and Allophanic soils) to release P to porewater and pondwater under short-term and frequent submergence. Five undisturbed soil blocks (20×20×15cm) were sampled from each soil. Porewater samplers and half-cell platinum electrodes for in-situ redox potential measurements were installed at 2 and 10cm depths from the soil surface. Six submerged events were created by maintaining a 5cm waterhead. Porewater and pondwater samples were collected immediately and three days after each submergence event. After three days of submergence, the soil blocks were drained and maintained at 70% of water holding capacity for 10 days before the next submergence event. Dissolved reactive phosphorus (DRP), pH, dissolved organic carbon, cations, anions, and alkalinity of the water samples were measured. Soil chemical P fractions were assessed in initial soils and soils in the middle and end of the experiment. Thermodynamic modelling was used to infer dissolution and formation of P and P-associated minerals. The Recent soil released P to porewater at both depths and to pondwater. The Pallic soil released P to porewater at both depths but did not change pondwater DRP. Allophanic soil sorbed P and did not increase DRP either in porewater or pondwater. The average pondwater DRP of the three soils during submergence were 17 to 65-fold higher than the New Zealand lowland river target DRP concentration (0.01mg/L). The mechanisms of P release from the Recent and Pallic soils were desorption and reductive dissolution of Mn(Ⅱ) minerals. Reductive dissolution of Fe(Ⅱ) minerals was not supported by fractionation or modelling results. Decreases in labile, moderately labile and stable P fractions contributed to P release in the Recent soil, while increases in the labile and moderately labile P fractions contributed to P retention in the Pallic and Allophanic soils. This study highlighted that the Recent soil is riskier than the other two soils in releasing P upon short-term submergence and the potential use of Allophanic soil as a P sorbing material in CSAs to mitigate P loss.