Physicochemical Interactions Research Articles

Intercellular junction-driven stromal cell stacking in a confined 3D microcavity.

Understanding the detailed mechanisms driving fibroblast migration within native tissue settings during pathophysiological events presents a critical research challenge. In this study, we elucidate how stromal cells migrate and contribute to the development of three-dimensional (3D) cellular aggregates within confined microcavities. Integrin α5β1 and β-catenin (β-cat) are central in guiding this collective migration and achieving optimal filling of the microcavity. When β-cat is suppressed, cells tend to migrate more sporadically, leading to less efficient cellular organization. Furthermore, we also detail the pivotal roles of Cx43 and N-cadherin (N-cad) in orchestrating collective migration and in shaping efficient cellular stacking. Suppressing gap junctions, especially Cx43, significantly impacts the extracellular matrix expression, integrin α5 and β1, and other elements in the 3D construct, emphasizing the importance of physicochemical cell-cell interactions. The distribution patterns of N-cad and focal adhesion kinase (FAK) further corroborate the essential roles in forming cell-cell junctions and FAK in establishing the foundational layer that underpins the cell stacking within the microcavity. Interestingly, neither Rho-associated protein kinase (ROCK) nor RhoA significantly alter the cell migration pattern toward microcavity. These findings provide fresh perspectives on fibroblast activities in 3D space, enriching our understanding and offering implications for advancements in wound healing and tissue engineering.

Experiment and simulation on the coupled effects of calcium leaching and chloride transport in concrete under hydraulic pressure

This study investigated the coupled effect of calcium leaching and chloride erosion on concrete subjected to hydraulic pressure by combining experiments and numerical simulations. Several tests including titration, pH, XRD, TG, MIP, and SEM-EDS were employed to analyze chloride concentration, pH value, solid phase compositions, and microstructure of concrete under hydraulic pressure. Concurrently, a model based on the physicochemical interactions between the pore solution and the hydration products was constructed to elucidate the process of calcium leaching and multi-ion transport. The experimental and simulation results reveal that hydraulic pressure accelerates calcium leaching in concrete, leading to a maximum porosity that reaches 1.5 times the initial porosity after a year. In addition, both the pH value and chloride binding capacity in the zone close to the exposure surface decrease. The enrichment of Ca2+ and OH− occurs at a specific depth within concrete during the calcium leaching process, and over time, this enrichment effect grows increasingly significant. Along the depth within the concrete, a transient increase in chloride binding capacity can be observed, which can be attributed to OH− and Ca2+ enrichment.

Adsorptive Removal of Dyes: A Comparison of Graphene Oxide to Granular Activated Carbon and Zeolite NaY

Synthetic carbon-based compounds are a prevalent wastewater contaminant that can adversely impact water resources due to their potential carcinogenic and toxic effects on aquatic biota and human health. This research investigates the versatility of graphene oxide (GO) as an alternative to commonly used adsorbents (zeolite NaY (NaY) and granular activated carbon (GAC)) for removal of synthetic cationic dyes. Rhodamine B (RhB) and methylene blue (MB), were selected as the target contaminants to represent cationic synthetic dyes with differing molecular sizes and structural compositions. Batch experiments using GO, NaY, and GAC as adsorbents were used to assess both physicochemical interactions between adsorbent surfaces and contaminants, and removal efficiency. GO demonstrated the highest removal efficiency for both target contaminants—at 99% and 86%, respectively—while the lowest removal efficiency was observed for NaY. Langmuir, Freundlich, Temkin, and BET isotherm models were used to describe the adsorption isotherms. Overall, GO demonstrated a more robust and higher removal efficiency of cationic dyes compared with GAC and NaY, indicating the potential of graphene oxide for the removal of complex structured organic contaminants in wastewater treatment.

Thermal analysis and modeling of phase equilibria in the NaCl–NaBr–Na2WO4 system

The phase complex of a three-component system of sodium chlorides, bromides and tungstates was studied for the first time using experimental and theoretical methods. It was found that the liquidus surface of the system consists of the crystallization fields of NaBr, Na2WO4, Na3ClWO4 compounds and NaClxBr1–x solid solutions. The differential thermal method of physico-chemical analysis (DTA) revealed the compositions and melting points of eutectic in the quasi–binary and three–component systems NaBr–Na3ClWO4 and NaCl–NaBr–Na2WO4, respectively. To establish the nature of the physico-chemical interaction in the system, three compositions were studied in the secondary triangle NaCl–NaBr–Na3ClWO4 by the DTA method, thermal effects of tertiary crystallization were not recorded on the DTA curves of these compositions, which is proof of the absence of a non-invariant composition in the NaCl–NaBr–Na3ClWO4 simplex. To determine the composition and melting point of the nonvariant composition located in the NaBr–Na2WO4–Na3ClWO4 simplex, a polythermal section located in the field of crystallization of sodium bromide and a nonvariant section emerging from the crystallization pole of sodium bromide passing through the point of joint crystallization of sodium chloride and the compound, with a constant decrease in the content of sodium bromide in the studied compositions before the onset of non-invariant crystallization process. The composition of the three-component eutectic of ED in molar percentages, crystallizing at 560оC with the following component content, has been determined: 7.5% NaCl; 38.5% NaBr; 54% Na2WO4. Based on data on the melting temperatures of the initial salts, compositions and crystallization temperatures of two- and three-component systems, a 3D-model of the “composition–temperature” phase complex in the temperature range 500–700оC was formed using theoretical methods. On the basis of the model, the isotherms of the liquidus surface and the T–x diagram of the polythermal section for which experimental studies were conducted was constructed. Also, as an example of using a 3D-model, the composition of the equilibrium phases released during cooling of an arbitrarily selected figurative point in the temperature range from 700 to 500оC. was calculated.

Adsorption of methyl orange and methylene blue on activated biocarbon derived from birchwood pellets

This study explored the adsorption capacity of a physically activated biocarbon derived from the pyrolysis of birchwood pellets (ABPB) towards two dyes - methyl orange (MO, anionic) and methylene blue (MB, cationic), at pH 2, 7 and 11. Compared to mineral commercial activated carbon (CACmineral), ABPB exhibited lower SSA, pores volume and surface; higher external surface and average pore diameter, similar ash content and aromaticity, and stronger hydrophilicity and polarity. The maximum adsorption capacity on ABPB was equal to 220 mg/g for MO and 91 mg/g for MB after 17 h. Batch tests with variable adsorbent amount (0.5–2.5 g/L) showed for both ABPB and CACmineral better results for lower adsorbent dose. Under all tested conditions, ABPB showed higher or analogous adsorption capacity compared to CACmineral. Based on the pKa of MB (3.80) and MO (3.46) and on the pHPZC of ABPB (5.3), the adsorption was favored at pH 2 for MO and at pH 11 for MB. Kinetics analysis and isotherm modelling revealed that, although many different physicochemical interactions occurred between ABPB and the dyes molecules, chemisorption is the rate-controlling step and prevalent mechanism. In conclusion, this study may provide support to further research aimed at exploring the effect of ABPB's physicochemical properties on the efficiency and mechanisms of dyes adsorption.

Effects of Frequency on the Performance of Ultrasonic Vibration Assisted Chemical Mechanical Polishing for Sapphire

Abstract Sapphire (Al2O3) is renowned for its exceptional properties, yet its unique natural presents a surface processing challenge. To enhance the polishing quality and efficiency, the sapphire ultrasonic vibration assisted chemical mechanical polishing (UV-CMP) has been proposed. This paper employs computational fluid dynamics (CFD) simulation and polishing experiments to investigate the action and mechanism of ultrasonic frequency on sapphire UV-CMP. The CFD simulation reveals that an increase in frequency can effectively elevate the fluid velocity, pressure, and cavitation. The enhancement in pressure, Z-direction, and resultant velocity has a positive impact on the cutting ability and utilization rate of nano-abrasives. A high frequency can enhance the physical fields of slurry, but it suppresses the growth of cavitation bubbles, and is detrimental to the number and size of abrasive particles. The best processing performance of sapphire UV-CMP is obtained at 40 kHz due to coordinated physicochemical interactions. X-ray photoelectron spectroscpy proves the product of solid-solid chemical reaction between nano-SiO2 and sapphire is softer Al2Si2O7 instead of Al2SiO5, which is beneficial to the material removal. This article provides theoretical and practical guidance for sapphire UV-CMP.

Physicochemical Interactions Between Concomitantly Administered Anti-Retroviral and Anti-Malarial Drug

Physicochemical Interactions Between Concomitantly Administered Anti-Retroviral and Anti-Malarial Drug

Synergistic role of prebiotics and probiotics in gut microbiome health: Mechanisms and clinical applications

AbstractPrebiotic and probiotic usage has exploded, with most formulations promoting gastrointestinal and immunological benefits. Prebiotics modulate the gut microbiota, as a result, short‐chain fatty acids are released into the bloodstream. Prebiotics have immunomodulatory properties that reduce inflammation while enhancing immune responses and boosting gut health. The potential of probiotics has shown steady expansion in the digestive system, metabolic balance, and vaginal health. Probiotics offer therapeutic and preventative strategies for a range of human diseases. The in vitro studies suggested the delivery matrix might influence their effects through physicochemical interactions with molecular and cellular structures as well as modifications in cellular expression. Dietary fibers and polyphenols both contribute significantly to human health protection and can ferment in the gut microbiota to create butyrate. This comprehensive review aims to highlight the probiotics and prebiotics, and provide evidence to support their use in preventive and therapeutic medicine. It is anticipated that it will help the clinical and preclinical research to look into the effects of inclusion and processing on their activity in different food delivery formulations. There are potential opportunities needed to enhance immunological and digestive health by comprehending and using the interaction between the gut microbiota and the immune system in our diet.

Mechanistic Study on the Optimization of Asphalt-Based Material Properties by Physicochemical Interaction and Synergistic Modification of Molecular Structure

In order to investigate the relationship between the molecular structure of fibers and the differences in physicochemical interactions between fibers and asphalt on the performance of fiber-modified asphalt, this paper chose two types of fibers with different chemical structures: straw fiber and polyester fiber. First, the differences in molecular interactions between the two fibers and asphalt were explored using molecular dynamics, then the differences in the adsorption capacity of the two fibers on asphalt components were tested by attenuated total reflection infrared spectroscopy experiments, and finally, the differences in the rheological properties of the two fiber-modified asphalts were tested by dynamic shear rheology and low-temperature creep experiments. The molecular dynamics simulation findings reveal that polyester fibers may intersperse into asphalt molecules and interact with them via structures such as aromatic rings, whereas straw fibers are merely adsorbed on the asphalt’s surface. Straw fibers and asphalt exhibit hydrogen bonding, whereas polyester fibers and asphalt display van der Waals interactions. The results of attenuated total reflectance infrared spectroscopy indicated that polyester fiber absorbed asphalt components better than straw fiber. The rheological tests revealed that the polyester fiber had the highest complex shear modulus in the temperature range of 46–82 °C, and at 64 °C, the phase angle was 4.289° lower than that of the straw fiber-treated bitumen. Polyester fiber-modified asphalt had a 32.48%, 15.72%, and 6.09% lower creep modulus than straw fiber-modified asphalt at three low-temperature conditions: −6 °C, −12 °C, and −18 °C. It is clear that fibers with aromatic rings as a chemical structure outperform lignin-based fibers in terms of improving asphalt characteristics. The research findings can serve as a theoretical foundation for the selection of fibers to produce fiber-modified asphalt.

Unlocking the wound healing potential of Anastatica hierochuntica L. (Kaff Maryam) Extract's nanosuspension: UPLC-MS/MS metabolic profiling, formulation development and statistical optimization

BackgroundAnastatica hierochuntica L. (Kaff Maryam) is a desert plant with documented therapeutic applications. Various medicinal uses have been reported for the plant extract such as antioxidant, anti-inflammatory, antifungal, antimicrobial, hypoglycemic, hypolipidemic, and hepatoprotective activities. The abundant plants constituents are promising and encourage the investigation of novel therapeutic uses. The principal objective of this study was to identify the bioactive constituents of A. hierochuntica (AH) by phytochemical profiling of its ethanolic extract, alongside an investigation of its wound healing efficacy after being formulated into nanosuspension for topical localized wound treatment. MethodA comprehensive metabolomics study of the ethanolic extract of A. hierochuntica aerial parts was assessed using UPLC MS/MS technique. Additionally, the preparation of AH nanosuspension was executed utilizing the antisolvent-precipitation method. A D-optimal experimental design was adopted to investigate the influence of variables such as: stabilizer ratio, antisolvent: solvent ratio, and stabilizer type on particle size (PS), polydispersity index (PDI), and zeta potential (ZP). The design also was employed in the optimization process. The selected optimal formula was further assessed for size characteristics, morphological identification by TEM, storage stability, FTIR, cytocompatibility with human skin fibroblast (HSF), and scratch assay on HSF to assess wound healing aptitude. ResultsChemical profiling of the aerial parts revealed an abundance of glucosinolates, flavonoids, flavolignans, and fatty acids. The optimized AH-nanosuspension showed small particle size (128.87 ± 26 nm), small PDI (0.136 ± 0.05), and high ZP absolute value (−37.53 ± 0.52 mV). Furthermore, TEM photography of the optimal nanosuspension formula exhibited circular non-aggregating nanosized particles. FTIR confirmed the successful formulation of the AH ethanolic extract into nanosuspension with no physicochemical interactions. Additionally, AH-nanosuspension demonstrated cytocompatibility with HSF with IC50 = 58.317 μg/mL. Moreover, both AH pure extract and AH-nanosuspension exhibited a remarkable cell migration rate and wound closure % which propounds an auspicious wound healing potential. ConclusionThe study accentuates the supremacy of the nanosized delivery approach of AH aerial parts ethanolic extract and warrants further in-vivo investigations to establish its clinical utility for wound management.

Assessing the Toxicity of Metal- and Carbon-Based Nanomaterials In Vitro: Impact on Respiratory, Intestinal, Skin, and Immune Cell Lines.

The field of nanotechnology has experienced exponential growth, with the unique properties of nanomaterials (NMs) being employed to enhance a wide range of products across diverse industrial sectors. This study examines the toxicity of metal- and carbon-based NMs, with a particular focus on titanium dioxide (TiO2), zinc oxide (ZnO), silica (SiO2), cerium oxide (CeO2), silver (Ag), and multi-walled carbon nanotubes (MWCNTs). The potential health risks associated with increased human exposure to these NMs and their effect on the respiratory, gastrointestinal, dermal, and immune systems were evaluated using in vitro assays. Physicochemical characterisation of the NMs was carried out, and in vitro assays were performed to assess the cytotoxicity, genotoxicity, reactive oxygen species (ROS) production, apoptosis/necrosis, and inflammation in cell lines representative of the systems evaluated (3T3, Caco-2, HepG2, A549, and THP-1 cell lines). The results obtained show that 3T3 and A549 cells exhibit high cytotoxicity and ROS production after exposure to ZnO NMs. Caco-2 and HepG2 cell lines show cytotoxicity when exposed to ZnO and Ag NMs and oxidative stress induced by SiO2 and MWCNTs. THP-1 cell line shows increased cytotoxicity and a pro-inflammatory response upon exposure to SiO2. This study emphasises the importance of conducting comprehensive toxicological assessments of NMs given their physicochemical interactions with biological systems. Therefore, it is of key importance to develop robust and specific methodologies for the assessment of their potential health risks.

Molecular Fractionation of Ancient Organic Compounds in Deeply Buried Halite Crystals.

The molecular fractionation of organic compounds through adsorption in minerals has wide implications, including tracing the origins of life, carbon sequestration, and climate change. Here we present the first in situ examination of molecular fractionation within individual crystals via optical-photothermal infrared (O-PTIR) spectroscopy. Our study focuses on a unique inclusion trail within deeply buried halite crystals, characterized by a distinctive orange-to-blue fluorescence gradient, providing primary evidence of molecular variation in ancient carbon-based fluids within the inclusion trail. The findings reveal a trend in the CH2/C=O and CH3/C=O ratios, conforming with a consistent decrease from the blue fluorescence region to the orange fluorescence region. The chemically influenced fluorescent behavior of these ancient liquid carbon-based compounds is attributed to the fractionation of fluids in the inclusions as a result of microfractures within the crystal acting as chromatography capillaries. These capillaries facilitated interactions between specific organic compounds, serving as adsorbates, and the halite mineral, representing the adsorbent. Our study provides insights into the fluid-solid physicochemical interactions within extreme environments and extends our understanding of molecular processes in such settings.

Exploring the physicochemical and rheological properties of sustainable asphalt binders modified with lignin and high-viscosity additive

The primary objective of this investigation is to evaluate how the incorporation of lignin and high-viscosity modifiers impacts the performance of asphalt binders. Lignin-modified asphalt binder (LBA) and lignin-high viscosity modifier composite-modified asphalt binder (LHA) were created by blending 5 % and 15 % lignin, respectively. To understand the physicochemical interactions, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) were employed to analyze functional groups, thermal properties, and phase changes. Additionally, the linear rheological behavior and nonlinear rheological behavior were evaluated through frequency sweep and multiple stress creep recovery tests. The findings suggest that lignin blends physically with the asphalt binder and high-viscosity modifier without a chemical reaction. Although the onset pyrolysis temperature of lignin is significantly lower than that of asphalt binders, due to its relatively low content, the thermal decomposition of lignin-modified asphalt binders is primarily controlled by the asphalt binder itself and still exceeds the construction temperature. However, lignin incorporation increases the asphalt binder's glass transition temperature, potentially affecting low-temperature performance. Lignin significantly enhances the modulus in the high-frequency region of both unmodified and high-viscosity modified asphalt binder. However, it has a negative effect on the modulus in the low-frequency region of high-viscosity modified asphalt binder. Furthermore, nonlinear creep recovery test results demonstrate that lignin positively contributes to the deformation resistance of unmodified asphalt binder in a content-dependent manner, whereas it reduces the elastic behavior and deformation resistance of high-viscosity modified asphalt binder. In addition, low levels of lignin increase the stress sensitivity of binders, while high levels of lignin decrease it. Despite these effects, the performance of lignin and high-viscosity additive composite-modified asphalt binder remains superior to that of unmodified asphalt binder. These findings offer valuable insights into the combined use of lignin and polymers in asphalt binder modification.

Fluorimetric Detection of Vapor Pollutants with Diketopyrrolopyrrole Polymer Microcavities.

The increasing prevalence and detrimental effects of volatile organic compounds are driving the need for selective on-site sensors that do not require complex sampling or instrumentation. Broadband selective sensors exhibiting selectivity based on their distinct response mechanism is becoming of increasing technological relevance in both industrial and urban settings. In this context, we propose a label-free sensor based on a polymeric planar microcavity embedded with a fluorescent organic dye, designed to detect various pollutants in the vapor phase. The sensor consists of alternating layers of cellulose acetate and poly(N-vinylcarbazole) and contains a polystyrene defect layer doped with a quadrupolar diketopyrrolopyrrole. Both the structural properties of the polymer microcavity and the dye in the defect layer contribute to the sensor's response to analytes, creating a dual-probe system where a single photonic element translates chemical signals into optical signals, namely, transmission and fluorescence spectral variations. The discrimination capability of the photonic structure arises from the physicochemical interactions between the analytes and the polymer components. To validate our approach, we evaluate the sensor's response to four distinct volatile molecules and investigate the mechanisms influencing the optical response.

How does the coupled action of freeze - Thaw and acidification affect the release of toxic elements from indigenous Zn smelting slags?

Under complicated field conditions, such as the coupled effects of freeze - thaw cycles (FTs) and acidification, the leaching behavior of potentially toxic element (PTEs) from indigenous Zn smelting slags (ZSS) was intricately connected to the mineralogy (e.g., the composition, assemblage, microstructure of mineral particles). In this study, FTs tests were carried out to explore the interactions between PTEs release and ZSS mineralogy. Subsequently, advanced characterization techniques were adopted to quantify the mineralogy and microstructure of ZSS. The results indicated that ZSS were mainly composed of silicate minerals (e.g., quartz, biotite and chlorite) and secondary Fe (III) oxyhydroxides (e.g., magnetite and limonite), accounting for 67.48% and 24.23%, respectively. The occurrence mode analysis revealed that 81.95% of As, 21.31% of Pb and 7.77% of Zn were hosted in limonite. About 37.89%, 59.34% and 34.50% of Cd, Pb and Zn were associated with carbonate bound fractions. Under FTs interacting with different pH conditions, the leaching concentrations of As, Cd, Cu, Pb and Zn did not significantly increase with the increase in FTs and pH. The microstructure damage of mineral particles in ZSS with the higher porosity was caused by both FTs and proton corrosion. More importantly, the geochemical modeling results suggested that the precipitation of hematite and magnetite might have little impacts on PTEs release under FTs and FTs with acidification. This work would provide a deeper understanding of PTEs release from smelting waste slags under complex physicochemical interactions.

Preventing bacterial adhesion to skin by altering their physicochemical cell surface properties specifically

The adhesion of bacteria to surfaces is associated with physicochemical and biological interactions. The present investigations provide new results about the differential adhesion levels of skin bacteria using a representative 3D skin model which mainly relies on the different physicochemical properties of the respective surfaces. Modulation of the adhesion of bacteria and thus their colonization, may occur by adjusting the physicochemical properties of the epidermal and bacterial surfaces. Lewis acid and hydrophobicity were the most strongly correlated parameters with the antiadhesion properties of the tested compounds. Modulation of physicochemical properties appears to be the primary driver of reduced Staphylococcus aureus adhesion in this study, with no significant changes observed in the expression of genes associated with classical adhesion pathways.

N-(4-(1,3-benzothiazol-2-ylcarbamoyl)phenyl)isonicotinamide as corrosion mitigator for mild steel in 1 M HCl: A multifaceted study integrating synthesis, characterization, and molecular modelling

Newly synthesized, cost-effective corrosion inhibitor, N-(4-(1,3-benzothiazol-2-ylcarbamoyl)phenyl)isonicotinamide (BIA) was evaluated for mild steel/1M HCl interface. BIA showed a maximum inhibition efficiency of 90.40 % at 100 ppm and 303 ± 1 K, with efficiency increasing with concentration but decreasing with temperature. Inhibitor’s adsorption followed Langmuir isotherm via physicochemical interactions. Activation parameters revealed BIA retards both metal dissolution and hydrogen evolution held in unimolecular process. Potentiodynamic polarization (PDP) divulged BIA as a mixed-type, impeding charge-transfer. Electrochemical impedance spectra (EIS) confirmed BIA forms a protective double layer, blocking active sites at the interface. Surface analysis supported a protective film formation. Global and local reactivity descriptors using DFT/B3LYP/6-311G++(d,p) were calculated to relate inhibition efficiency with BIA’s electronic properties. Molecular dynamics simulation (MDS) showed an interaction energy of −224.7 kJ/mol between BIA and Fe(110) at 303 K, with Radial Distribution Function (RDF) showing bond lengths under 3.5 Å, confirming a chemical interaction. Theoretical results align with experimental data.

Quantitative investigation of temperature-dependent bound water degeneration in bentonite clays

Temperature increases in saturated clay alter the physicochemical clay-water interactions and may lead to the conversion of bound water into free water. These changes significantly influence the physical, chemical, and engineering properties of clays, which are critical for geotechnical and geological engineering and minimizing risks in areas with expansive clay soils. However, quantifying this phenomenon remains challenging in the literature. This study presents a robust experimental approach for quantifying the thermal-induced conversion of bound water in clays, providing valuable insights into the mechanisms governing their thermo-mechanical behavior. A novel experimental method is proposed to quantify the degenerated bound water content in a clay system subjected to temperatures ranging from 20 to 50 °C. The research employs the siphon principle to examine volume changes in a clay system at elevated temperatures, focusing on measuring the conversion of bound water to free water. This method accounts for thermal expansion of both the soil constituents and the confining glass cylinder, as well as potential evaporation losses. To validate the setup's accuracy, a calibration test using standard Ottawa sand with negligible bound water was performed. After measuring system error, the primary outcome was calibrated. Results showed that at 30 °C, 40 °C, and 50 °C, 3 %, 9 %, and 15 % of the initial bound water, respectively, converted to free water.

Short-term interactions between Longmaxi shale and carbon dioxide-based fracturing fluids

The shale is a dense quarried rock material containing abundant shale oil/gas. Extracting shale gas usually requires fracturing the rock formation to speed up gas desorption and migration. Supercritical carbon dioxide fracturing, as an environmentally friendly and waterless fracturing technique of reservoir stimulation, gains increasing recognition in commercial exploitation of shale oil and gas. However, there is insufficient understanding on the interaction between carbon dioxide-based fracturing fluids and shale, as well as its influence on the mechanical parameters of shale, which are pivotal for determining injection parameters and forming the fracture network. This study focuses on the injection of carbon dioxide-based fracturing fluids to enhance shale gas extraction and carbon dioxide sequestration. Simulation tests of injection were conducted to investigate the influence of different fracturing fluids (deionized water, gaseous/supercritical carbon dioxide, gaseous/supercritical carbon dioxide mixed with brine) injected into shale reservoirs on the microstructure and mechanical properties of shale after short-term physicochemical interaction. This article adopts research methods such as uniaxial compression and uniaxial tensile mechanical experiments based on acoustic emission monitoring and various physical characterizations such as scanning electron microscopy, X-ray diffraction, X-ray fluorescence spectrometer, etc. Results show that following treatment with different carbon dioxide-based fluids, the uniaxial tensile/compressive strength, elastic modulus, fractal dimension of pore structure, and the brittleness index of shale exhibit varying degrees of decrease compared to those of dry untreated shale samples. After interacting with different carbon dioxide-based fracturing fluids, the mechanical parameters and brittleness index of shale decrease more significantly than that of the others as the addition of brine. This study shows that the water in carbon dioxide-based fracturing fluids is a controlling factor affecting the elastic modulus of shale. Additionally, the ductility of the shale increases and the acoustic emission emitting lag due to the coupling effects of brine and carbon dioxide. The change law of the elemental and mineral composition of the shale is consistent with the mechanical strength; and the change of element content and mineral composition is the most significant. Compared to gaseous carbon dioxide, the supercritical carbon dioxide has a greater impact on mineral composition of the shale. The change of mechanical strength and microstructure evolution mechanism caused by the short-term interactions between the shale and fracturing fluids provide theoretical references and implications for the determination of injection parameters and permeability transformation of the Longmaxi shale reservoirs.

In Silico Analysis of the Molecular Interaction between Anthocyanase, Peroxidase and Polyphenol Oxidase with Anthocyanins Found in Cranberries.

Anthocyanins are bioactive compounds responsible for various physiological processes in plants and provide characteristic colors to fruits and flowers. Their biosynthetic pathway is well understood; however, the enzymatic degradation mechanism is less explored. Anthocyanase (β-glucosidase (BGL)), peroxidase (POD), and polyphenol oxidase (PPO) are enzymes involved in degrading anthocyanins in plants such as petunias, eggplants, and Sicilian oranges. The aim of this work was to investigate the physicochemical interactions between these enzymes and the identified anthocyanins (via UPLC-MS/MS) in cranberry (Vaccinium macrocarpon) through molecular docking to identify the residues likely involved in anthocyanin degradation. Three-dimensional models were constructed using the AlphaFold2 server based on consensus sequences specific to each enzyme. The models with the highest confidence scores (pLDDT) were selected, with BGL, POD, and PPO achieving scores of 87.6, 94.8, and 84.1, respectively. These models were then refined using molecular dynamics for 100 ns. Additionally, UPLC-MS/MS analysis identified various flavonoids in cranberries, including cyanidin, delphinidin, procyanidin B2 and B4, petunidin, pelargonidin, peonidin, and malvidin, providing important experimental data to support the study. Molecular docking simulations revealed the most stable interactions between anthocyanase and the anthocyanins cyanidin 3-arabinoside and cyanidin 3-glucoside, with a favorable ΔG of interaction between -9.3 and -9.2 kcal/mol. This study contributes to proposing a degradation mechanism and seeking inhibitors to prevent fruit discoloration.