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Environmentally persistent free radicals (EPFRs) play an important role in aerosol effects on air quality and public health, but their atmospheric abundance and sources are poorly understood. We measured EPFRs contained in PM2.5 collected in Fairbanks, Alaska, in winter 2022. We find that EPFR concentrations were enhanced during surface-based inversion and correlate strongly with incomplete combustion markers, including carbon monoxide and elemental carbon (R2 > 0.75). EPFRs exhibit moderately good correlations with PAHs, biomass burning organic aerosols, and potassium (R2 > 0.4). We also observe strong correlations of EPFRs with hydrocarbon-like organic aerosols, Fe and Ti (R2 > 0.6), and single-particle mass spectrometry measurements reveal internal mixing of PAHs, with potassium and iron. These results suggest that residential wood burning and vehicle tailpipes are major sources of EPFRs and nontailpipe emissions, such as brake wear and road dust, may contribute to the stabilization of EPFRs. Exposure to the observed EPFR concentrations (18 ± 12 pmol m-3) would be equivalent to smoking ∼0.4-1 cigarette daily. Very strong correlations (R2 > 0.8) of EPFR with hydroxyl radical formation in surrogate lung fluid indicate that exposure to EPFRs may induce oxidative stress in the human respiratory tract.

Electronic (e-) cigarette formulations containing nicotine salts from a range of organic acid conjugates and pH values have dominated the commercial market. The acids in the nicotine salt formulations may alter the redox environment in e-cigarettes, impacting free radical formation in e-cigarette aerosol. Here, the generation of aerosol mass and free radicals from a fourth-generation e-cigarette device was evaluated at 2 wt % nicotine salts (pH 7, 30:70 mixture propylene glycol to vegetable glycerin) across eight organic acids used in e-liquids: benzoic acid (BA), salicylic acid (SLA), lactic acid (LA), levulinic acid (LVA), succinic acid (SA), malic acid (MA), tartaric acid (TA), and citric acid (CA). Furthermore, 2 wt % BA nicotine salts were studied at the following nicotine to acid ratios: 1:2 (pH 4), 1:1 (pH 7), and 2:1 (pH 8), in comparison with freebase nicotine (pH 10). Radical yields were quantified by spin-trapping and electron paramagnetic resonance (EPR) spectroscopy. The EPR spectra of free radicals in the nicotine salt aerosol matched those generated from the Fenton reaction, which are primarily hydroxyl (OH) radicals and other reactive oxygen species (ROS). Although the aerosol mass formation was not significantly different for most of the tested nicotine salts and acid concentrations, notable ROS yields were observed only from BA, CA, and TA under the study conditions. The e-liquids with SLA, LA, LVA, SA, and MA produced less ROS than the 2 wt % freebase nicotine e-liquid, suggesting that organic acids may play dual roles in the production and scavenging of ROS. For BA nicotine salts, it was found that the ROS yield increased with a higher acid concentration (or a lower nicotine to acid ratio). The observation that BA nicotine salts produce the highest ROS yield in aerosol generated from a fourth-generation vape device, which increases with acid concentration, has important implications for ROS-mediated health outcomes that may be relevant to consumers, manufacturers, and regulatory agencies.

GaCH2, a free radical thought to play a role in the chemical vapor deposition of gallium-containing thin films and semiconductors, has been spectroscopically detected for the first time. The radical was produced in a pulsed discharge jet using a precursor mixture of trimethylgallium vapor in high pressure argon and studied by laser-induced fluorescence and wavelength resolved emission techniques. Partially rotationally resolved spectra of the hydrogenated and deuterated species were obtained, and they exhibit the nuclear statistical weight variations and subband structure expected for a 2A2–2B1 electronic transition. The measured spectroscopic quantities have been compared to our own ab initio calculations of the ground and excited state properties. The electronic spectrum of gallium methylene is similar to the corresponding spectrum of the aluminum methylene radical, which we reported in 2022. [ABSTRACT FROM AUTHOR]

C4F7N/CO2 gas mixtures have attracted extensive attention because of their excellent insulating properties and environmental friendliness. High electrical and thermal stability is an important indicator for evaluating their performance, but there have been few molecular dynamics studies of their decomposition mechanisms. In this study, using ReaxFF molecular dynamics simulations and quantum chemistry theory, the decomposition mechanism of a C4F7N/CO2 gas mixture and the effect of the O2 content on the decomposition of the mixture were simulated on the microscopic level. It was found that there are three main decomposition pathways of C4F7N molecules, of which the generation of C3F4N⋅ and CF3⋅ free radicals is the most likely to occur. COF2 is the main oxygen-containing product of the C4F7N/CO2 gas mixture, and its generation is significantly affected by the simulation time and temperature. COF2 can be regarded as the characteristic decomposition product of the C4F7N/CO2 gas mixture. The addition of O2 slightly promotes the decomposition of C4F7N, whereas the maximum decomposition rate of CO2 decreases by 0.3% and 1% after the addition of 2% and 8% O2, respectively. Relevant results of this research can provide a theoretical basis and guidance for research into the performance of C4F7N/CO2 gas mixtures and practical engineering applications of these mixtures in the future. [ABSTRACT FROM AUTHOR]

Absolute line strengths of several transitions in the ν1 fundamental band of the hydroxyl radical (OH) have been measured by simultaneous determination of hydrogen peroxide (H2O2) and OH upon laser photolysis of H2O2. Based on the well-known quantum yield for the generation of OH radicals in the 248-nm photolysis of H2O2, the line strength of the OH radicals can be accurately derived by adopting the line strength of the well-characterized transitions of H2O2 and analyzing the difference absorbance time traces of H2O2 and OH obtained upon laser photolysis. Employing a synchronized two-color dual-comb spectrometer, we measured high-resolution time-resolved absorption spectra of H2O2 near 7.9 µm and the OH radical near 2.9 µm, simultaneously, under varied conditions. In addition to the studies of the line strengths of the selected H2O2 and OH transitions, the kinetics of the reaction between OH and H2O2 were investigated. A pressure-independent rate coefficient kOH+H2O2 was determined to be [1.97 (+0.10/−0.15)] × 10−12 cm3 molecule−1 s−1 at 296 K and compared with other experimental results. By carefully analyzing both high-resolution spectra and temporal absorbance profiles of H2O2 and OH, the uncertainty of the obtained OH line strengths can be achieved down to <10% in this work. Moreover, the proposed two-color time-resolved dual-comb spectroscopy provides a new approach for directly determining the line strengths of transient free radicals and holds promise for investigations on their self-reaction kinetics as well as radical–radical reactions. [ABSTRACT FROM AUTHOR]

To investigate the influence of gangue left in goafs on the low-temperature oxidation characteristics of coal, the variations of gas products and free radical parameters of coal-gangue mixed samples with different gangue contents were tested. The results show the concentration of gas products is directly proportional to temperature and inversely proportional to gangue content (except the sample with 20% gangue content (G(20))). In addition, the oxygen consumption rate and heat release intensity follow a variation trend similar to that of gas product. Pure gangue corresponds to the highest apparent activation energy, 57.6 kJ/mol, and G(20) has the lowest value, 48.8 kJ/mol. With the rise of temperature, the free radical concentration of the mixed samples decreased slowly when it was lower than 90°C and higher than 210°C, and increased between 90°C and 210°C. Compared with the theoretical calculation results, the mixed samples all possess higher gas product, oxygen consumption rates, heat release intensities, free radical concentrations and lower apparent activation energy in the experiments, which indicates that gangue can remarkably promote the reaction of coal during low-temperature oxidation. As a result, the gangue left in goafs may promote the risk of coal spontaneous combustion. [ABSTRACT FROM AUTHOR]

The fundamental combustion field of ammonia-hydrogen fuel is being extensively researched. However, studies on the laminar burning velocity (LBV) under high pressure with varying hydrogen concentration conditions are relatively scarce. This study innovatively used the constant volume method (CVM) to measure LBV of ammonia-hydrogen fuels with various hydrogen concentrations X H2 = 15%–30%, initial temperatures T i = 298–428 K, initial pressures P i = 1–3 bar, and equivalence ratios ϕ = 0.8–1.4. The LBV of the fuel mixture up to the temperature and pressure of 540 K and 7 bar under isentropic adiabatic assumption was determined with the CVM method. The results illustrate that the enhancing effect of hydrogen concentration on LBV is suppressed under high pressures, supporting the argument that the equivalence ratio associated with the maximum LBV is solely determined by the initial fuel composition. Chemical kinetics simulations were also analyzed including flame structure, sensitivity analysis, and reaction pathways. It indicated that the elementary reaction H + O 2 <=>O + OH predominantly governs the LBV of ammonia-hydrogen. An increase in hydrogen concentration intensifies this process by boosting the concentration of free radical hydrogen, albeit with a concomitant rise in NO emissions due to nitrogen-containing radical oxidation. Conversely, an increase in initial pressure diminishes NO emissions by strengthening the pathway from NO to NNH. The findings of this study enhance the LBV database of ammonia-hydrogen fuel at high pressures and high temperatures, and can further act as a reference for other experiments. • Investigated NH 3 /H 2 /Air laminar burning velocity via the constant volume method. • Provided the laminar burning velocity data under continuously elevating temperature and pressure. • Analyzed the impact of elevated hydrogen concentration and pressure on NO emissions. • Findings show that increased pressure aids in reducing NO emissions by promoting its consumption. [ABSTRACT FROM AUTHOR]

Isolating high-performance phenol degradation microorganisms with high salt tolerance and studying their resistance mechanisms are urgent issues. To address these issues, a typical bacteria (Klebsiella sp. YP-1) with high salt and phenol tolerance was isolated. Its strategies for resisting high salt and high phenol stress were studied. The results indicated that Klebsiella sp. YP-1 was able to degrade 1000 mg/L phenol within 44 h at 70 g/L NaCl, which was faster than most microorganisms reported in the literature. Lyxose secreted by Klebsiella sp. YP-1 played an important role on assisting Klebsiella sp. YP-1 to resist stress. Lyxose increased phenol degradation rate by microorganisms due to its protection on cell membrane. Quantum chemical calculation results indicated that lyxose was more likely attacked by free radical than cell membrane. In addition, lyxose could bind to the cell membrane through hydrogen bonds. Thus, lyxose prevented reactive oxygen species from harming cell membranes. Moreover, lyxose has broad protective effect on microbial cell membranes. This study provides a novel idea for microorganisms to resist oxidative stresses. [Display omitted] • A strain of Klebsiella sp. YP1 with high salt-phenol tolerance was isolated. • A novel strategy for Klebsiella sp. to resist stress was presented: secreting lyxose. • Lyxose improves the ability of microbe to degrade high salt-phenol wastewater. • The mechanism of lyxose protecting cell membrane was revealed for the first time. • Lyxose has broad protection effect on microbial cell membranes. [ABSTRACT FROM AUTHOR]

New isatin-thiosemicarbazone (1–6) were obtained from various 5-methylisatin and various isothiocyanates with good yields and efficient methods. The structures of the synthesized compounds were clarified by FT-IR, 1H-NMR, and 13C-NMR spectroscopic techniques and elemental analysis. The antioxidant activity properties of the compounds were investigated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method and total reducing power determinations. In our total reducing power study, where we chose Trolox as the standard antioxidant, it was found that the reducing powers of compounds containing different substituent groups and positions were close to each other and lower than Trolox. In the study using butylated hydroxytoluene (BHT) as a reference antioxidant, DPPH antiradical scavenging capacities of the synthesized compounds were determined. The free radical scavenging effects of the synthesized compounds were compared with the IC50 values obtained from the concentration equations and were found in the order BHT > 6 > 3 > 5 > 1 > 2 > 4. Structural and electronic properties of the compounds were examined by density functional theory (DFT) calculations and their relationship with the antioxidant properties of the compounds was discussed. DFT calculations played an important role in determining how the electronic properties of the synthesized compounds, especially in the presence of different substituents and in the ortho and meta positions, and accordingly the antioxidant properties of the compounds, changed. Experimental and theoretical results confirmed that methoxy-containing structures in the synthesized compounds exhibit higher antioxidant effects compared to halogen-containing structures, regardless of their position. [ABSTRACT FROM AUTHOR]

In this study, tetradecyl methacrylate-maleic anhydride-benzylidene acetone (C14MC-MA-MCA) terpolymers were synthesized via free radical polymerization and evaluated as pour point depressants (PPDs) for coal-based diesel. The findings indicate that the C14MC-MA-MCA (3:1:1) terpolymer exhibited the most effective inhibition of the solid point (SP) at 1500 ppm concentration. Specifically, it reduced the SP of coal-based diesel from − 4 to − 42 °C, marking a significant decrease of 38 °C. Furthermore, the crystallization behavior and SP reduction mechanism of C14MC-MA-MCA in coal-based diesel were investigated using viscosity analysis and polarized optical microscopy (POM). [ABSTRACT FROM AUTHOR]

BACKGROUND: Freshly extracted sugarcane juice is an ideal substrate for microbial fermentation and browning reactions. The present study is the first report on the potential of pulsed light (PL) processing in improving microbial stability with the retention of major bioactive. PL processing at different levels of voltage (2.1–2.7 kV) and number of pulses (100–200) was explored. The present study aimed to investigate the impact of PL processing on the quality of sugarcane juice, bioactive composition and microbial load. RESULTS: The microbial load, such as aerobic mesophiles, yeast and mold, and total coliform, was reduced to below 1 log colony‐forming units mL−1 in juice samples subjected to intense PL treatment at 2.7 kV. The maximum value of the total color difference of the sugarcane juice was below 4.0, even at extreme levels of PL process parameters. In comparison with the unprocessed juice, the reduction in total phenols (Folin ciocalteu reagent assay) and the total antioxidant capacity (2,2‐diphenyl‐1‐picrylhydrazyl free radical scavenging assay) was limited to 6% and 16.7%, respectively, when treated at 2.7 kV/200 pulses. The pH and total soluble solids of the juice remained unaffected in all the processed samples. Among the process parameters considered, the treatment voltage was found to significantly affect the quality parameters and microbial load. CONCLUSION: PL processing at 2.1 kV/170 pulses gave an optimally processed juice with a microbial load below the permissible limit and desirability value of 0.77. The results suggest that the PL treatment is effective for enhancing the microbial stability and maintaining the bioactive components of the sugarcane juice. Furthermore, the outcomes from the present study are expected to pave the way for further in‐depth investigation of the effect of PL treatment on the critical quality attributes and shelf life of sugarcane juice. The technology will be useful for adoption by different stakeholders, including manufacturers and retailers in the food processing sector. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Groundwater contamination in India exposes an estimated 70 million people to arsenic. Over 10 million people in the state of Bihar (India) are at risk of arsenic poisoning. As reported 27 districts of the state's thirty-eight districts are under a state of catastrophe. Symptoms noticed by those who have been exposed to the arsenic caused disease are-lack of appetite, neurobehavioral problems, hyperkeratosis, and melanosis on the skin. So, this study's primary objective is to find novel approaches to treat arsenic poisoning in rats using the Charles Foster model. Following permission from the Institutional Animal Ethics Committee, the animals were divided into three groups: one group served as a control, the second group received arsenic treatment, and the third group received Ganoderma lucidum extract after arsenic treatment. For the arsenic group, the rats were given 8 mg/kg body weight of sodium arsenite orally every day for 90 days, and then for 60 days, they were given 80 mg/Kg body weight of Ganoderma lucidum extract via gavage. Their biochemical values, including those of the liver and kidneys, were found to be increased. In addition, their levels of free radicals, including lipid peroxidation, were measured and found to be substantially higher. In addition, the levels of arsenic in the kidney and liver tissue were very high. However, biochemical and lipid peroxidation levels were significantly restored after administration of Ganoderma lucidum ethanolic extract. Arsenic levels in rat liver and kidney tissues were also found to be reduced. Ganoderma lucidum has a therapeutic impact against arsenicinduced toxicity, according to the present research. [ABSTRACT FROM AUTHOR]

The spontaneous combustion and gas explosion induced by crushed small coal pillars and the residual coal of adjacent goaf will cause a large amount of coal loss and casualties of workers. Moreover, it also seriously pollutes the environment and aggravates the greenhouse effect. To effectively block small coal pillars and fracture zones of adjacent old workings is the key to prevent gas and coal spontaneous combustion in small coal pillars. However, the commonly used blocking materials at present are easy to shrink and chap after air drying, and they have no chemical inhibitory property. Thus, these materials cannot realize the coordinated prevention of gas and coal spontaneous combustion. In this paper, a low-cost and eco-friendly Synergistic Inhibiting and Sealing Material (SISM)with strong inhibitory properties is proposed. The optimal ratio of the material was determined by experiments. The inhibitory properties of the material are analyzed by testing and comparing the generation rate of free radical and CO generation rate. The experimental results showed that the optimal molar ratio of main antioxidant and auxiliary antioxidant was 5:2, and the optimal mass ratio of synergistic antioxidant and high water material was 1:8. Secondly, SISM can prevent or delay the production of new free radicals during coal spontaneous combustion, significantly reduce the concentration of free radicals in coal and finally delay the process of coal spontaneous combustion. Thirdly, both physical and chemical inhibitory properties are taken into account when preparing SISM. Hence, it can maintain both high inhibitory properties in the whole temperature range and the inhibition effect on coal-oxygen compound reaction, which is significantly better than MgCl2 and yellow mud (YM) with only physical inhibition. [ABSTRACT FROM AUTHOR]

Taxodium ‘Zhongshanshan’ is a distinctive tree known for its rapid growth and robust stress resilience. To enhance the utilization of forestry resources, tannin extracts were procured from the barks (BE) and leaves (LE) of Taxodium ‘Zhongshanshan’. The tannin structures were characterized by FT-IR and MALDI-TOF MS, and found to be condensed tannin with a degree of polymerization not exceeding 6. The tannin extracts exhibited a potent ability to scavenge free radicals at capacities of 60–80 % compared to Vitamin C (VC). They inhibited the bacterial strains Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), with a pronounced effect on the latter. Furthermore, tannin from Taxodium ‘Zhongshanshan’ appears benign and have no significant effect on cell activity. [ABSTRACT FROM AUTHOR]

To investigate the combustion characteristics of non-stick coal and the formation patterns of main combustion products and radicals, this study initially conducted a TG-DSC experiment of non-stick coal. Subsequently, non-stick coal was characterized and analyzed using XPS and 13C NMR experiments, and a molecular model with the formula C208H199O23N3S was constructed. Subsequently, the ReaxFF MD method was employed to simulate the combustion molecular dynamics of the non-stick coal periodic mixing model under varying oxygen content and temperature conditions. The analysis focused on elucidating the formation patterns of free and primary products during combustion. Experimental findings indicate that the combustion of non-stick coal progresses through stages, including water evaporation and desorption (30–145.65 °C), dynamic equilibrium (145.65–181.76 °C), oxygen weight gain (181.76–263.56 °C), thermal decomposition (263.56–379.14 °C), combustion (379.14–562.04 °C) and burnout (562.04–800 °C). The ignition temperature of non-stick coal was determined to be 379.14 °C. The simulation results indicate that an increase in temperature and oxygen content further enhances the relatively stable peak production of CO2. The peak increase of CO production is weaker than that of CO2. The rise in temperature also promotes the formation of H2O, while the increase in oxygen content initially enhances and subsequently inhibits the peak production of H2O. H radicals, O radicals, and OH radicals are primarily generated through the decomposition reactions of small molecular compounds or other free radicals. Free radical polymerization and the decomposition of small molecular compounds represent the primary pathways for the formation of CO, CO2, and H2O. [ABSTRACT FROM AUTHOR]

Hydrogen (H2) therapy is an emerging, novel, and safe therapeutic modality that uses molecular hydrogen for effective treatment. However, the impact of H2 therapy is limited because hydrogen molecules predominantly depend on the systemic administration of H2 gas, which cannot accumulate at the lesion site with high concentration, thus leading to limited targeting and utilization. Biomaterials are developed to specifically deliver H2 and control its release. In this review, the development process, stimuli‐responsive release strategies, and potential therapeutic mechanisms of biomaterial‐based H2 therapy are summarized. H2 therapy. Specifically, the produced H2 from biomaterials not only can scavenge free radicals, such as reactive oxygen species (ROS) and lipid peroxidation (LPO), but also can inhibit the danger factors of initiating diseases, including pro‐inflammatory cytokines, adenosine triphosphate (ATP), and heat shock protein (HSP). In addition, the released H2 can further act as signal molecules to regulate key pathways for disease treatment. The current opportunities and challenges of H2‐based therapy are discussed, and the future research directions of biomaterial‐based H2 therapy for clinical applications are emphasized. [ABSTRACT FROM AUTHOR]

Free radical generation plays a key role in many biological processes including cell communication, maturation, and aging. In addition, free radical generation is usually elevated in cells under stress as is the case for many different pathological conditions. In liver tissue, cells produce radicals when exposed to toxic substances but also, for instance, in cancer, alcoholic liver disease and liver cirrhosis. However, free radicals are small, short-lived, and occur in low abundance making them challenging to detect and especially to time resolve, leading to a lack of nanoscale information. Recently, our group has demonstrated that diamond-based quantum sensing offers a solution to measure free radical generation in single living cells. The method is based on defects in diamonds, the so-called nitrogen-vacancy centers, which change their optical properties based on their magnetic surrounding. As a result, this technique reveals magnetic resonance signals by optical means offering high sensitivity. However, compared to cells, there are several challenges that we resolved here: Tissues are more fragile, have a higher background fluorescence, have less particle uptake, and do not adhere to microscopy slides. Here, we overcame those challenges and adapted the method to perform measurements in living tissues. More specifically, we used precision-cut liver slices and were able to detect free radical generation during a stress response to ethanol, as well as the reduction in the radical load after adding an antioxidant. [ABSTRACT FROM AUTHOR]

Oxidative species, generated endogenously via metabolism or from exogenous sources, play crucial roles in the body. At low levels, these species support immune functions by participating in phagocytosis. They also aid in cellular signaling and contribute to vasomodulation. However, when the levels of oxidative species exceed the body's antioxidant capacity to neutralize them, oxidative stress occurs. This stress can damage cellular macromolecules such as lipids, DNA, RNA, and proteins, driving the pathogenesis of diseases and aging through the progressive deterioration of physiological functions and cellular structures. Therefore, the body's ability to manage oxidative stress and maintain it at optimal levels is essential for overall health. Understanding the fundamentals of oxidative stress, along with its reliable quantification, can enable consistency and comparability in clinical practice across various diseases. While direct quantification of oxidant species in the body would be ideal for assessing oxidative stress, it is not feasible due to their high reactivity, short half-life, and the challenges of quantification using conventional techniques. Alternatively, quantifying lipid peroxidation, damage products of nucleic acids and proteins, as well as endogenous and exogenous antioxidants, serves as appropriate markers for indicating the degree of oxidative stress in the body. Along with the conventional oxidative stress markers, this review also discusses the role of novel markers, focusing on their biological samples and detection techniques. Effective quantification of oxidative stress may enhance the understanding of this phenomenon, aiding in the maintenance of cellular integrity, prevention of ageassociated diseases, and promotion of longevity. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The implementation of Salix psammophila sand barriers measures constitutes a crucial element in desertification control, providing a solid theoretical foundation for the future application and pretreatment of sand barriers in production practices. To address the specific damage types predominant in desert environments, we executed simulations of ultraviolet irradiation and rainfall phenomena on mechanical sand barriers in sandy areas and also inspected the variations in chemical properties during accelerated aging processes. The findings unequivocally demonstrate that: (1) The synergistic impact of ultraviolet irradiation and water accelerated the deformation and fracturing of the S.psammophila sand barriers, thereby causing a partial degradation of its chemical properties and conspicuous lignin oxidation; (2) The fissure of the sand barrier deepened, resulting in structural alterations. The existence of water expedites the degradation process of S.psammophila sand barriers under ultraviolet irradiation. (3)With respect to the binding form of C atoms, the carbon atoms at S.psammophila sand barriers were highly oxidized after 576 hours of accelerated aging. The components of C2 (C-O) and C3 (C=O) rising to 40.16% and 12.24% respectively, while the components of C1 (C-C) declined to 47.60%. The amount of hydroxyl (O-C-O), carbonyl (C=O), and carboxyl (O-C=O) groups increases in line with the expansion of the contact area between the sand barrier structure and ultraviolet irradiation as well as water. More free radical substances are generated, thereby causing the chemical binding properties to tend to be more stable. In summary, Ultraviolet irradiation and water change are the primary factors influencing the degradation of S.psammophila sand barriers material structure and properties. In future desertification control, it is imperative to focus on enhancing the longevity of sand barriers by ensuring their waterproofing capabilities and resistance to ultraviolet irradiation. [ABSTRACT FROM AUTHOR]

The current study explores the effects of microwave treatment at varying wattage and durations on the phytoconstituents, antioxidant status, anti-nutritional factors (ANFs), and metabolite profiles of de-oiled rice bran. The total phenolics and flavonoids showed both increases and decreases depending on specific microwave parameters, while flavonol content consistently increased across all treated groups compared to the control. The DPPH and ABTS free radical scavenging activity, total antioxidant capacity, FRAP, CUPRAC, metal chelating activity, and ascorbic acid content were enhanced in most of the microwaved samples; however, longer microwave exposure at higher wattage led to their reduction. A treatment-specific decrease in ANFs, including condensed tannins, oxalates, and phytates, was observed. HRMS-based untargeted metabolomics identified a diverse range of primary and secondary metabolites, which clustered in a group-specific manner, indicating notable group-wise metabolite variations. Analysis of discriminating metabolites revealed no significant differences in the overall levels of phenolics, flavonoids, vitamins and cofactors, sugars, amino acids, terpenoids, fatty acids, and their derivatives among the treated groups compared to the control; however, several individual metabolites within these metabolite classes differed significantly. These findings suggest that optimized microwaving of de-oiled rice bran can enhance phytochemicals and antioxidants while improving the metabolite profile. [ABSTRACT FROM AUTHOR]

AbstractThe synthesis of a novel large type double-layered cyclophanes has been successfully accomplished by free radical coupling reaction with the bis(N-alkylene benzothiazolium) dibromide salts as their important synthetic intermediates. The structures of the two-layered cyclophanes and the synthetic intermediates have been elucidated based on the NMR data and X-ray structural analysis, respectively. The two-layered cyclophanes consist of two different geometries, anti-two cyclic lactam amide rings inside and two bridges of disulfide bonds outside, which are unique and novel structures. Their physical properties were investigated by UV–Vis and redox potential, too. [ABSTRACT FROM AUTHOR]

When the level of reactive oxygen species (ROS) increases abnormally in the body, it damages tissue cells and is closely related to the occurrence of various chronic diseases. Antioxidant peptides (APs) are a class of active short peptides with antioxidant capacity, which have great research value. In this paper, two APs were designed and synthesized based on the structural features of APs: CHIWM (AP1) and CHCPWM (AP2). The reactive sites and activities of APs were analyzed using the quantum chemical density functional theory (DFT) method. The reactive sites are all located in the indolyl heterocycle of tryptophan residues, among which AP1 has a smaller energy gap and single point energy. Multiple free radical scavenging assays showed that AP1 and AP2 had stronger antioxidant activity than the positive control, glutathione (GSH). For scavenging DPPH free radicals, the IC50s values were 0.613 mg/mL and 0.606 mg/mL, respectively. In cellular assays, both AP1 and AP2 were able to scavenge ROS in the cells and attenuate cellular damage. In conclusion, AP1 and AP2 designed in this paper have good antioxidant activity and have the potential to be applied in the treatment of chronic diseases caused by cellular oxidative damage. [ABSTRACT FROM AUTHOR]

As one of the mainstream biodegradable materials, poly(butylene adipate-co-terephthalate) (PBAT) foams offer a sustainable alternative to traditional plastic foams, effectively reducing environmental pollution. However, the high cost and poor mechanical performance of PBAT foams impede their practical application. Herein, the glycidyl methacrylate-grafted biomass lignin (GML) was used to produce a PBAT/GML composite foam with good foaming performance and mechanical properties at high lignin-filling amounts by twin-screw melting free radical polymerization and supercritical CO2 foaming process. The compatibility of GML in the PBAT matrix was improved due to the formation of ester bonds in modified lignin, endowing the PBAT/GML (PGML) composite foam with exceptional foaming performance. Additionally, the mechanical properties of PGML composite foam were remarkably enhanced due to the introduction of the abundant aromatic structures of GML and the construction of a stable covalent crosslinking network. The compressive strengths and compression modulus of the PGML foam were improved by 2.53 times and 2.47 times, while its bending strength and bending modulus were improved by 1.27 times and 3.92 times compared to the neat PBAT. This research affords a new strategy for developing low-cost biodegradable biomass PBAT/lignin composite foam materials with good foaming performance and mechanical properties. [ABSTRACT FROM AUTHOR]

Increased intramitochondrial free iron is a key feature of various liver diseases, leading to oxidative stress, mitochondrial dysfunction, and liver damage. Polydatin is a polyphenol with a hepatoprotective effect, which has been attributed to its ability to enhance mitochondrial oxidative metabolism and antioxidant defenses, thereby inhibiting reactive oxygen species (ROS) dependent cellular damage processes and liver diseases. However, it has not been explored whether polydatin is able to exert its effects by protecting the phospholipid cardiolipin against damage from excess iron. Cardiolipin maintains the integrity and function of electron transport chain (ETC) complexes and keeps cytochrome c bound to mitochondria, avoiding uncontrolled apoptosis. Therefore, the effect of polydatin on oxidative lipid damage, ETC activity, cytochrome levels, and ROS production was explored in iron-exposed rat liver mitochondria. Fe2+ increased lipid peroxidation, decreased cardiolipin and cytochromes c + c1 and aa3 levels, inhibited ETC complex activities, and dramatically increased ROS production. Preincubation with polydatin prevented all these effects to a variable degree. These results suggest that the hepatoprotective mechanism of polydatin involves the attenuation of free radical production by iron, which enhances cardiolipin levels by counteracting membrane lipid peroxidation. This prevents the loss of cytochromes, improves ETC function, and decreases mitochondrial ROS production. [ABSTRACT FROM AUTHOR]

The exhaustion of conventional light oils necessitates the shift towards unconventional sources such as biomass, heavy oil, oil shale, and coal. Non-catalytic thermal cracking by a free radical mechanism is at the heart of the upgrading, prior to refining into valuable products. However, thermal pyrolysis is hindered by the formation of asphaltenes, precursors to coke, limiting cracking, causing equipment fouling, and reducing product stability. Free radicals are inherently present in heavy fractions and are generated during thermal processes. This makes these reactive intermediates central to understanding these mechanisms and limiting coking. Electron spin resonance (ESR) spectroscopy facilitates such mechanistic studies. Over the past decade, there has been no review of using in-situ ESR for studying thermal processes. This work begins with a brief description of free radicals' chain reactions during thermal reactions and the wealth of information ESR provides. We then critically review the literature that uses ESR for mechanistic studies in thermal pyrolysis of biomass, heavy oil, shales, and coal. We conclude that limited literature exist, and more investigations are necessary. The key findings from existing literature are summarized to know the current state of knowledge. We also explicitly highlight the research gaps. [ABSTRACT FROM AUTHOR]

Alternating copolymers are crucial for diverse applications. While dispersity (Ð, also known as molecular weight distribution, MWD) influences the properties of polymers, achieving low dispersities in alternating copolymers poses a notable challenge via free radical polymerizations (FRPs). In this work, we demonstrated an unexpected discovery that dispersities are affected by the participation of charge transfer complexes (CTCs) formed between monomer pairs during free radical alternating copolymerization, which have inspired the successful synthesis of various alternating copolymers with low dispersities (>30 examples, Ð=1.13–1.39) under visible‐light irradiation. The synthetic method is compatible with binary, ternary and quaternary alternating copolymerizations and is expandable for both fluorinated and non‐fluorinated monomer pairs. DFT calculations combined with model experiments indicated that CTC‐absent reaction exhibits higher propagation rates and affords fewer radical terminations, which could contribute to low dispersities. Based on the integration of Monte Carlo simulation and Bayesian optimization, we established the relationship map between FRP parameter space and dispersity, further suggested the correlation between low dispersities and higher propagation rates. Our research sheds light on dispersity control via FRPs and creates a novel platform to investigate polymer dispersity through machine learning. [ABSTRACT FROM AUTHOR]

The (BiO)4CO3(OH)2/BiOBr heterojunction was developed by a facile hydrothermal process using polyhedral (BiO)4CO3(OH)2 as the precursor and HBr as the etching agent. BiOBr nanosheets were vertically and orderly grown on the surface of (BiO)4CO3(OH)2, and the obtained (BiO)4CO3(OH)2/BiOBr heterojunction exhibits outstanding photocatalytic performance to degrade 50 mg L−1 of Cr(VI) and 30 mg L−1 of TC in 25 and 20 min, respectively, under simulated sunlight. The enhanced photocatalytic performance is the synergistic effect of the two factors: the unique hierarchical structure can effectively utilize light, and the suitable position of the band edge is conducive to the construction of a Z-scheme heterostructure. The free radical capture confirms that superoxide free radicals (˙O2−) and hydroxyl radicals (˙OH) are the major active agents during photocatalysis. Based on the transient photocurrent response and electrochemical impedance measurements, the (BiO)4CO3(OH)2/BiOBr heterostructure shows excellent separation efficiency of the photogenerated electron–hole pairs. This finding will inspire many researchers to develop novel high-performance photocatalysts for degrading harmful and toxic pollutants and remediating environmental pollution. [ABSTRACT FROM AUTHOR]

Although the fundamental configuration (tetrahedron-type and capsule-type) of Zr-MOCs is well understood, the synthesis of amino-functionalized Zr-based capsule (denoted as ZrC-1-NH2) based on 2-aminoterephthalic acid remains a considerable challenge. Fortunately, we obtained single crystals under solvothermal conditions and further achieved the rapid synthesis of ZrC-1-NH2 with pure phase and high yield using a microwave-assisted solvothermal method. In addition, ZrC-1-NH2 was utilized as a photocatalyst to perform the degradation of tetracycline (TC) in water. The degradation efficiency of 92.3% was achieved at the optimal conditions, and the main active free radical was determined as ·O2− according to the trapping agent experiment and EPR results. Furthermore, the possible degradation pathway of TC was proposed. [ABSTRACT FROM AUTHOR]

After cerebral ischemia, the brain encounters noxious stimuli that result in a dysfunctional balance between the production and elimination of reactive oxygen species, which in turn cause damage to cellular components. Oxidative stress may activate the inflammatory response, promoting apoptosis, autophagy, etc. Flavonoids are present in a wide range of foods and have antioxidant, anti-inflammatory, antimutagenic and anticancer properties. Dietary flavonoid intake have beneficial effects against ischemic stroke. Dietary flavonoids can significantly reduce the risk of ischemic stroke and improve its prognosis by directly scavenging free radicals, regulating redox balance, and modulating signaling pathways and gene expression to counteract the cellular damage of brain caused by oxidative stress after ischemic stroke. Therefore, this review summarizes the effect of dietary flavonoids against oxidative stress on ischemic stroke. [ABSTRACT FROM AUTHOR]

Myracrodruon urundeuva, popularly known as 'aroeira-do-sertão', a large tree, with a tall trunk. Belonging to the Anacardiaceae family, it occurs in the 'caatinga' and dry forests of Brazil, from Ceará to the states of Paraná and Mato Grosso do Sul. The present study aimed to analyse the whitening and antioxidant activities of the aqueous extract of the leaves of Myracrodruon urundeuva (AELMU). Inhibition of the tyrosinase enzyme, as well as its copper chelating capacity and antioxidant effect were evaluated. The AELMU (at 2000 µg/mL) showed excellent inhibitory action (83.76%) on tyrosinase by chelating the copper ion while kojic acid at the same concentration inhibited 97.81%. Moreover, the extract displayed important antioxidant activity (inhibited 76,46% of the 2,2-diphenyl-1-picrylhydrazyl radical - DPPH; 49,59% of thiobarbituric acid reactive substances and 51,07% of the hydroxyl radical). Thus, the extract under study is promising for use in cosmetics, given its multifactorial action. [ABSTRACT FROM AUTHOR]

Diblock copolymers of phenyl methacrylate (PMA) and butyl methacrylate (BMA) were synthesized using dual-wavelength photopolymerization with a bifunctional photoinitiator 2-(4-(2-hydroxy-2-methylpropanoyl)phenoxy)ethyl(E)-3-(1-methyl-1H-pyrrol-2-yl)acrylate (PAA-2959). [ABSTRACT FROM AUTHOR]

In this study, two characteristics of boehmite nanoparticles (BNs) were used to improve the dynamic‐mechanical properties of pure unsaturated polyester resin (Neat UP). (1) Boehmite's ability to target free radical control in the radical curing reaction of UP resin, and (2) adsorption of alkyd chains and creation of attractive interactions with the resin network. X‐ray diffraction (XRD), Fourier‐transform infrared spectroscopy (FT‐IR), and field‐emission scanning electron microscopy (FESEM) analysis were used to identify the synthesis of particles. The results of FESEM analysis showed that the average particle size was 80–100 nm. TGA was used to investigate the thermal properties of the Neat UP and UP resin containing 0.3 wt% BNs (UP 0.3 BNs). The results of the dynamic‐mechanical analysis showed that the elastic modulus of the UP 0.3 BNs composite increased by 42% compared to the Neat UP. To investigate the significant increase observed in the dynamic‐mechanical properties, the curing kinetics were investigated by differential scanning calorimetry (DSC). Investigating the activation energy in terms of the conversion degree showed earlier dominance of the diffusion phenomenon in the UP 0.3 BNs composite. Investigating the diffusion factors provided by Vyazovkin–Sbirrazzouli showed a significant decrease in K and ED in the UP 0.3 BNs composite (−10.5, 19 kJ/mol) compared to the Neat UP resin (−9.5, 40 kJ/mol). Highlights: Targeted control of free radicals increases network regularity of the UP/BNs.Impressive improvement of mechanical properties of UP/BNs compared to Neat UP.Increasing diffusion phenomenon dominance of UP/BNs system compared to Neat UP. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Inflammatory infiltration of synovial M1 macrophages, high levels of ROS, and NO exacerbate osteoarthritis (OA) progression. The PdZn/CoSA‐NC nanozymes, which are highly ordered PdZn intermetallic nanoparticles loaded with Co single atom N‐doped carbon‐rich in multi‐level pores, in an attempt to serve as SOD and CAT mimicking nanozymes for OA therapy is designed. The PdZn/CoSA‐NC nanozymes' high electron transfer and dual active site sufficient exposure enhances free radical adsorption and lower reaction energies, accelerating SOD‐like, CAT‐like, and GPx‐like catalyzed reactions, outperforming CoSA‐NC and PdZn/NC alone. Furthermore, PdZn/CoSA‐NC nanozymes exhibit favorable biocompatibility, reduce synovial macrophage oxidative stress in OA, alleviate hypoxia, restore mitochondrial function, regulate energy metabolism, increase antioxidant factors, and reduce inflammatory factors, thus effectively mitigating the progression of OA. Mechanistically, PdZn/CoSA‐NC nanozymes downregulate M1‐type phenotypic markers like IL‐1β by regulating purine metabolism. The PdZn/CoSA‐NC nanozymes offer a novel approach to treating oxidative stress‐related inflammatory diseases. [ABSTRACT FROM AUTHOR]

ABSTRACT Hyaluronic acid (HA) is extensively utilized in biomedical applications, and its functionality can be enhanced by introducing aldehyde groups (─CHO) through oxidation. In this study, cold atmospheric plasma (CAP) was used to treat aqueous HA solutions, resulting in the formation of plasma‐modified HA (PMHA) containing ─CHO groups. The free radicals generated from interactions between water molecules and CAP particles reacted with HA, leading to the oxidation of hydroxyl groups into ─CHO and the cleavage of glycosidic bonds, causing molecular depolymerization. The PMHA was then used to synthesize hydrogels in combination with carboxymethyl chitosan and ɛ‐polylysine. This study presents an effective approach for generating HA with aldehyde functionalities and offers insights into the interaction between CAP and polysaccharides. [ABSTRACT FROM AUTHOR]

We report on the synthesis, structure and reactivity of [{NCNMe4}Sb(C6H2-tBu2-3,5-O-4)] (3), an organoantimony(III)-oxyaryl species obtained upon Csp2–H bond activation in a phenolate ligand and stabilised by the monoanionic pincer {NCNMe4}−. The mechanism leading to the formation of 3 is highly sensitive to steric considerations. It was probed experimentally and by DFT calculations, and a number of intermediates and related complexes were identified. All data agree with successive heterolytic bond cleaving and bond forming processes involving charged species, rather than a pathway involving free radicals as previously exemplified with congeneric bismuth species. The nucleophilic behaviour of the oxyaryl ligand in 3, a complex that features both zwitterionic and quinoidal attributes, was illustrated in derivatisation reactions. In particular, insertion of CS2 in the Sb–Coxyaryl bond generates [{NCNMe4}Sb(S2C-C6H2-tBu2-3,5-O-4)]. [ABSTRACT FROM AUTHOR]

In this article, a CRET-based chemiluminescent sensor was developed for ascorbic acid detection. Au/Pt@Cu2O/CuO NPs with peroxidase activity were prepared to catalyse the decomposition of H2O2 to produce free radicals, which led to the enhancement of the chemiluminescence (CL) signal, and the CRET between luminol and MnO2 NSs was able to take place and the CL signal was reduced; the presence of ascorbic acid would reduce MnO2 NSs, which was able to weaken the energy transfer between luminol and MnO2 NSs and restored the CL signal. Under the optimal experimental conditions, the detection range of ascorbic acid was 1–1000 μM, and the LOD was 0.35 μM. The method is sensitive and has a wide linear range, and is expected to be applied to the detection of ascorbic acid in more complex environments. [ABSTRACT FROM AUTHOR]

5-Lipoxygenase (5-LOX) is a key enzyme involved in the biosynthesis of pro-inflammatory leukotrienes, leading to asthma. Developing potent 5-LOX inhibitors are highly attractive. In this research the previously synthesized isoxazole derivatives has been investigated against 5-LOX inhibitory and antioxidant in vitro assay. The compound 3 caused concentration dependent inhibition of 5-LOX with overall IC50 value of 8.47 μM. The investigated compounds C5 also exhibited good 5-LOX inhibitory effect. The IC50 demonstrated for C5 was 10.48. Among the 10 synthesized compounds, the potential 5-LOX inhibitory effect was reported for C6. The most potent compound which showed excellent free radical scavenging effect was C3 having IC50 value of 10.96 μM. The next most potent antioxidant activity was reported for C5 which non-significantly showed free radical scavenging effect. The IC50 value observed for C5 was 13.12 μM. Compound C6 also showed potent dose dependent antioxidant effect with IC50 value of 18.87 μM having percent inhibition of 91.63±0.55, 88.45±0.49, 83.53±0.45, 78.42±0.66 and 73.72±0.64 at concentration 1000–62.5 μg/mL respectively. Among the tested compounds, C6 was found most potent which showed significant 5-LOX percent inhibition assay and also reported the minimum IC50 value comparable to the reference drug. The in vitro 5-LOX enzymes inhibition assays of C5 and C3 also showed excellent percent inhibition and good potency next to C6. We concluded that amongst the investigated designed molecules the C3 was found best potent and showed significant dose dependent antioxidant activity against DPPH screening. The IC50 value reported for C3 was found good as compared to standard drug. Moreover, C5 and C6 also showed excellent free radical scavenging effect against DPPH assay. Computational methods have also been employed to explore the probable interaction model of inhibitors and enzyme active sites, and also to correlate the results of in silico and in vitro studies. [ABSTRACT FROM AUTHOR]

Turbinaria ornata, Polycladia myrica, and Padina pavonica is a perennial Mediterranean-native seaweed that is commonly used for mass display. The principal aims of this reconnaissance were the isolation of various compounds from methanolic seaweeds extraction and screening the potential effect as antibacterial, and antioxidant. The micro-dilution method was used to measure antibacterial activity. Gas chromatography-mass spectrophotometry (GC. Mass) abused to analyze the chemical components of the methanolic seaweed extract. The existence of 19 secondary metabolites was discovered using GC–MS analysis: 8 different compounds for each seaweed's species. Among these bioactive compounds, 4 compounds from P. pavonica extract showed the binding affinity and ability to react with Beta-ketoacyl synthase (PDB ID 1EK4) of Escherichia coli. The phytocompounds' drug-like and poisonous characteristics were predicted. Auto Dock was used to examine the ligand receptor complexes' binding strength. T. ornate and P. pavonica had the highest activity against K. pneumonia, with 22.50 mm (0.78 µg/ml) and 22.23 mm (5.10 µg/ml) obtained, respectively. In a concentration-dependent manner, the extract components demonstrated substantial antioxidant activity. P. pavonica had the highest scavenging activity (78.00%, IC50 = 6.35 µg/ml), while ascorbic acid had a 96.45% scavenging impact. Because the chemicals bind to the Lipinski Ro5, they have drug-like characteristics. The compounds had no hepatotoxic effects. P. pavonica extract has the prospect of being used as a source of medicinal drug-like chemicals. The docking investigation found a strong correlation between the experimental results and the docking results. Finally, brown seaweed extract, particularly P. pavonica extract, demonstrated strong antibacterial, antioxidant, and free radical scavenging properties. [ABSTRACT FROM AUTHOR]

Simple Summary: In fish farming, protein is the most expensive macronutrient in the diet. Research on the physiology of fish nutrition has focused on the relationships between nutrient intake and animal development and metabolism. The dynamics of protein metabolism are influenced by the body's nutrient needs and dietary protein and energy intake. The Amazonian Pintado, a crossbred hybrid of Pseudoplatystoma reticulatum × Leiarius marmoratus, is farmed due to its growth rate, feed conversion efficiency, carcass yield, and absence of intramuscular bones. This study aimed to evaluate the effects of dietary digestible protein levels on muscle growth dynamics and oxidative stress in the white muscle of Amazonian Pintado. The results revealed that high dietary levels of digestible protein, despite increasing protein and free amino acid concentrations in the muscle, restrict muscle hypertrophy and increase tissue exposure to oxidative damage in Amazonian Pintado farming. This study aimed to evaluate the effects of dietary digestible protein levels on the growth dynamics and oxidative stress status of white muscle fibers in Amazonian Pintado (Pseudoplatystoma reticulatum × Leiarius marmoratus). Four hundred and fifty-five juveniles of Amazonian Pintado were fed diets containing varying digestible protein levels (225, 250, 275, 300, 325, 350, or 375 g kg−1) for 75 days. At the end of the experiment, the fish were fasted for 24 h, anesthetized, and euthanized to obtain muscle samples. The linear and quadratic effects of dietary digestible protein levels on white muscle fiber diameter, metabolite concentrations, and oxidative stress were assessed. The results revealed that increasing dietary digestible protein levels linearly raised the concentrations of free amino acids and total proteins in muscle tissue but also led to elevated levels of TBARS, indicating increased oxidative stress. Notably, the average area of muscle fibers with a cell area greater than 1133 µm2 decreased, reflecting restricted muscle hypertrophy, whereas glycogen and glucose levels also declined. These findings suggest that although high dietary digestible protein enhances protein and free amino acid concentrations in muscle tissue, it may compromise muscle hypertrophy and increase oxidative damage in Amazonian Pintado, underscoring the complexity of optimizing diet formulation. [ABSTRACT FROM AUTHOR]

Background: In people with type 1 diabetes mellitus, free radical activity is a major contributor to vascular problems. However, there is a dearth of information on vascular consequences in type 2 diabetes mellitus. Objectives: This research evaluated the free radical activity of individuals with type 2 diabetes who had hypertension to those who did not. Supplies and Procedures: Fifty type 2 diabetes outpatients had their blood levels of the lipid peroxidation product MDA (malondialdehyde), the free radical scavenger SOD (superoxide dismutase), and NO (nitric oxide) measured. The diabetic outpatients without hypertension were considered the controls. Result: Among 50 patients thus studied 18 were hypertensive. The concentration (median (range)) of both SOD (20.31(5.33-26.64) vs. 16.65(6.66-22.64) U/dl; p< 0.05) and NO (19.54 (11.40-37.07) vs.20.40 (15.69-35.65) U/dl; p< 0.05) were reduced in the hypertensive group. Similarly, concentration (median (range) of MDA (354(231-718) vs. 390(256-666)lmoles/dl; p< 0.01 were increased in thehypertensive group.. Conclusion: In comparison to healthy controls, we concluded that our study shows a considerable increase in free radical activity in Type II diabetes patients. [ABSTRACT FROM AUTHOR]

The aging process is influenced by the accumulation of both beneficial and harmful factors in the external environment. While extensive literature has explored the health benefits of short-term forest bathing, the potential for long-term exposure to forests to delay the aging process remains unclear. This study aimed to investigate the impact of prolonged urban forest contact on aging using a murine model. Forty male Specified Pathogen Free degree Kunming mice (6 weeks old, average weight 30.44 ± 0.91 g) were subjected to continuous subcutaneous injection of D-galactose in an urban environment and an urban forest environment to simulate an accelerated aging process lasting six weeks. Results showed that compared to urban environment, mice living in the forest environment exhibited significantly increased levels of serum oxidases CAT, GSH-Px, and SOD, as well as decreased levels of oxidative products H2O2 and MDA. These findings suggest that long-term forest living enhances serum Nrf2 expression, downstream oxidase activity, total antioxidant capacity, and resistance to free radicals and oxidative products, thus delaying the aging process. This study offers valuable insights into the potential health benefits of long-term forest living, which may play a role in delaying the aging process in humans. [ABSTRACT FROM AUTHOR]

Context: An inclusion complex between 2,2′-azobis(2-methylpropionamidine) dihydrochloride (AAPH), a widely employed azocompound, and cucurbit[7]util (CB[7]), has shown an increased yield of radicals derived from the homolytic cleavage of the azo bond. Aimed to get insights about the formation of complexes and their effect on the yield of radicals production, complexes of CB[7] with seven azocompounds were studied by computational methods. Molecular electrostatic surfaces and structural analysis showed that the inclusion of symmetrical azocompounds inside of CB[7] depends mainly on the charge density and position of the functional groups at the main chain of the azoderivative. Analysis of non-covalent interactions and thermodynamic outcomes revealed that positively charged azocompounds with amidinium or imidazolium groups presented strong favorable interactions (multiple hydrogen bonds) with the oxygens of CB[7] portals. Additionally, carbon-centered radicals generated from the complexes (azocompounds@CB[7]) were corroborated using the electron localization function (ELF). Results evidenced that the strength of the interactions and the level of inclusion (partial or complete) between the azocompound and CB[7] determined the final orientation of the radicals (located out- or inside of the CB[7] cavity). Obtained results could be employed to design new supramolecular systems based on the properties of azocomplound@CB[7] complexes for new scientific or industrial applications. Methods: First-principles calculations at B3LYP-D3BJ/6-311g(d,p) level theory in the gas phase and in solvent (PCM, water) were performed in Gaussian 16 software package. The dispersion energy correction was included through the Grimme's dispersion with Becke-Johnson damping D3(BJ). Thermodynamical data and the minimum character of all structures were obtained from vibrational frequency calculations. NBO, Multiwfn, Chemcraft, and NCIPLOT software were used to perform population analysis, analyze outcomes, visualize data, and display non-covalent interactions respectively. [ABSTRACT FROM AUTHOR]

Background: Environmentally persistent free radicals (EPFRs) are generated in the combustion processes of solid waste and can cause adverse influences on human health, especially lung diseases. Lung cancer is one of the most serious malignancies in recent years, which the global deaths rate is about 1.6 million every year. Methods and Results: In this study, we verified that ZnO/MCB EPFRs promote cell proliferation and migration, impedes cell apoptosis in lung cancer. Furthermore, we found that ZnO/MCB could influence the expression of miRNAs (miR-18a and miR-34a). In vivo, ZnO/MCB and ZnO EPFRs can reduce the weight and survival rate of BALB/c male mice more than that of BALB/c female mice. In the ZnO/MCB exposed group, male mice lung became even smaller, while the female mice the lung increased significantly. Taken together, our results provide evidence for assessing the potential health risks of persistent free radicals on fine particles. Conclusions: This study linked toxicity of EPFRs with miRNAs revealed the potential health hazard to human lung cancer. [ABSTRACT FROM AUTHOR]

Lubricin, secreted primarily by chondrocytes, plays a critical role in maintaining the function of the cartilage lubrication system. However, both external factors such as friction and internal factors like oxidative stress can disrupt this system, leading to osteoarthritis. Inspired by lubricin, a lubricating nanozyme, that is, Poly‐2‐acrylamide‐2‐methylpropanesulfonic acid sodium salt‐grafted aminofullerene, is developed to restore the cartilage lubrication system using an "In‐Out" strategy. The "Out" aspect involves reducing friction through a combination of hydration lubrication and ball‐bearing lubrication. Simultaneously, the "In" aspect aims to mitigate oxidative stress by reducing free radical, increasing autophagy, and improving the mitochondrial respiratory chain. This results in reduced chondrocyte senescence and increased lubricin production, enhancing the natural lubrication ability of cartilage. Transcriptome sequencing and Western blot results demonstrate that it enhances the functionality of mitochondrial respiratory chain complexes I, III, and V, thereby improving mitochondrial function in chondrocytes. In vitro and in vivo experiments show that the lubricating nanozymes reduce cartilage wear, improve chondrocyte senescence, and mitigate oxidative stress damage, thereby mitigating the progression of osteoarthritis. These findings provide novel insights into treating diseases associated with oxidative stress and frictional damage, such as osteoarthritis, and set the stage for future research and development of therapeutic interventions. [ABSTRACT FROM AUTHOR]

NH3 is a highly promising zero‐carbon fuel. In this paper, 19 important reactions involving NH3, NH2, and NH in the ammonia system are studied to better establish the combustion reaction mechanism of ammonia. These reactions encompass the reactions of NH3, NH2, and NH with free radicals and inorganic compounds such as O, H, OH, NO, H2O, and O2. Utilizing the transition state theory and Yao‐Lin method, energy barrier diagrams for these reactions are presented, and the harmonic and anharmonic rate constants are calculated over the temperature range from 300 to 4000 K. The calculation results reveal that, in most reactions, the harmonic rate constants exceed the anharmonic rate constants and the experimental results are closer to the anharmonic rate constants. Additionally, the kinetic and thermodynamic parameters are fitted. To summarize, most reactions are significantly influenced by the anharmonic effect. [ABSTRACT FROM AUTHOR]