Radical Formation Research Articles

Unravelling the role of silver in addressing the nitrate radical induced photocatalytic oxidation of olefins to epoxides or carbonyl compounds

Nitrate radicals possess the unique capability to add to unsaturated bonds, leading to the formation of carbon-centred radicals evolving to organic compounds, which cannot be achieved through more common reactive oxygen centred species. Therefore, the possibility of generating nitrate radicals through heterogeneous photocatalysis endows this technology with unprecedented possibilities in the field of green organic synthesis. In particular, previous research showcased the promising potential of nitrate radicals in selectively conducting the photocatalytic oxidative cleavage of limonene to limononaldehyde. However, the role of silver ions, required for the reaction to occur, remained uncertain. This study aims at elucidating the role of silver in determining conversion of limonene and selectivity towards the corresponding oxidized compounds. In particular, it has been demonstrated that silver ions efficiently scavenge photogenerated electrons, thus making molecular oxygen available for the nitrate radical induced production of limononaldehyde, obtained with selectivity values up to 60%. In this study it is shown that, nitrate radical formation is as well boosted by silver nanoparticles, in the absence of silver ions. However, in this case, the consequent oxidation of limonene produced both 1,2-limonene epoxide and limononaldehyde. Notably, in the absence of silver ions, molecular oxygen is the main electron scavenger and its lower availability for the oxidative cleavage mechanism addresses the reaction towards the epoxide. Ab initio calculations, confirmed this hypothesis, showing that, while formation of limononaldehyde is thermodynamically and kinetically favoured, formation of the epoxide is kinetically limited. Therefore, its formation takes place when the formation of limononaldehyde is hindered by factors such as the reduced availability of molecular oxygen. The identification of key parameters governing the process offers possibilities to tune the selectivity of the reaction towards oxidative cleavage or epoxidation. Moreover, it allows to further optimize this reaction, which may become an appealing and versatile method of chemicals green synthesis.

Textile dyes removing from the wastewater by green synthesized Cu-doped ZnO photocatalysts under the simulated sunlight illumination

Herein, Cu-doped ZnO photocatalysts were prepared via green synthesis method with utilization of Cannabis Sativa leaves. The catalytic activity was evaluated through the degradation of methylene blue (MB) and rhodamine B (RhB) under the simulated sunlight illumination. XRD, FESEM, EDAX, FTIR, BET-BJH and DRS were used for characterizations of Cu-doped ZnO. The results showed that, 3 wt % Cu-doped ZnO (CuZn3) displayed the excellent characterizations such as uniform dispersion, lower energy bandgap, smaller average particle size and greater surface area. For the photocatalysts with higher Cu loading (more than 3 wt %), non-uniform dispersion with larger particles, lower specific surface area and higher energy bandgap were found. The average particle size and energy bandgap for CuZn3 were 37.7 nm and 2.9 eV, respectively. Due to the superior properties, CuZn3 presented the highest amount of dyes degradations. After 180 min test, MB and RhB degradations by CuZn3 were 92.1 and 94.2 %, respectively. Moreover, it was found that optimum amount of CuZn3 was 100 ppm. Furthermore, applying of various scavengers revealed that hydroxyl radicals, superoxide radicals, and photo-generated electrons were the primary forms of radicals involved in dyes degradation using Cu-doped ZnO photocatalysts.

Azido derivatives of sesquiterpene lactones: Synthesis, anticancer proliferation, and chemistry of nitrogen-centered radicals

Sesquiterpene lactones (SLs) such as parthenolide (PTL) and dehydroleucodine (DhL) selectively kill cancer cells without exerting normal tissue toxicity, potentially due to presence of α-methylene-γ-lactone (αMγL) fragment. We hypothesize that the addition of an azido group to the αMγL fragment of PTL or DhL further augments their anticancer properties as well as radiation sensitivity of cancer cells. Azido-SLs containing the azido group at the C14 methyl position of PTL (i.e., azido-melampomagnolide B, AzMMB) while preserving the mechanistically crucial exomethylene unit of αMγL fragment were also prepared. Sham-irradiated (i.e., unirradiated control) or irradiated human breast cancer cells (MCF7) were treated with different concentrations of azido-PTL (AzPTL) or azido-DhL (AzDhL) along with parental SLs. Proliferation rate of MCF7 cells were measured by MTT-assay, and their colony forming ability was determined by colony formation assay. Both AzPTL and AzDhL significantly suppress proliferation rate and colony forming ability of MCF-7 cells. AzPTL suppressed colony forming ability, not cellular proliferation, following irradiation to a greater extent than PTL at lower concentrations (5 and 10 μM). Electron spin resonance (ESR) studies were performed employing gamma-irradiated homogeneous supercooled aqueous solutions to investigate radical formation through addition of radiation-mediated prehydrated electrons to the azide group of AzPTL and AzDhL and to follow subsequent reactions of these radicals. In AzPTL, formation of a tertiary carbon-centered radical plausibly via a metastable aminyl radical was observed, whereas AzDhL produced both π-aminyl and α-azidoalkyl radicals. These radicals may contribute to the antitumor activities of AzPTL and AzDhL.

Low plasma melatonin levels negatively correlate with melasma severity

Background: Chronic exposure to ultraviolet light plays a role in the pathogenesis of melasma. Exposure to excessive sunlight leads to the formation of free radicals. As a result, the body responds by forming antioxidants such as melatonin, which is activated through the melatoninergic antioxidative system to fight oxidative stress. The relationship between melatonin and melasma is yet to be elucidated. This study aims to determine the correlation between melatonin and the severity of melasma. Methods: This analytical cross-sectional study involved 50 melasma subjects and 10 non-melasma subjects who met the inclusion criteria and were aged between 21-50 years at Prof. I.G.N.G. Ngoerah National General Hospital, Denpasar. The severity of melasma was measured by calculating the melasma area severity index (MASI) score and plasma melatonin levels were assessed using the ELISA method. Results: The median plasma melatonin level in the melasma subjects was lower (92.48 ng/ml) than in non-melasma subjects (436.35 ng/ml), with a p-value of Conclusion: Low plasma melatonin levels negatively-correlate with the severity of melasma.

Tapping into the Power of Sol-Gel Method for Enhanced Antimicrobial Activity of Titania Nanoparticles

Increasing bacterial resistance to antibiotics has become a serious threat to global public health. In this context, this study aims to evaluate the antimicrobial activity of titanium dioxide nanoparticles (TiO2 NPS) synthesized using the sol-gel method. TiO2 NPS samples were prepared and characterized for morphology via field-emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) analysis. Kirby-Bauer disc diffusion method was used to test the antimicrobial activity of TiO2 NPS against Gram positive bacteria Staphylococcus aureus, Gram negative bacteria Escherichia coli, and pathogenic fungus Aspergillus penicillioides. The results showed that TiO2 NPS effectively inhibited the growth of microorganisms, with significant inhibition zones especially against fungi. The antimicrobial mechanism of TiO2 NPS involves the formation of hydroxyl radicals and superoxide ions that damage the cell membrane of microorganisms. The implications of this study are the development of potential antimicrobial nanomaterials for biomedical and environmental applications, as well as the importance of considering the physical and chemical properties of TiO2 NPS in designing effective infection treatment strategies.

The danger of microwave ovens in relation to free radicals formation, cellular inflammation, cancer initiation, and cancer progression

The US National Cancer Institute defines cancer as a disease in which some of the body’s cells grow uncontrollably and then spread to other parts of the body. Cancer is a major cause of death globally and based on the World Health Organization (WHO) most recent data it accounts for about 10 million deaths annually. Cancer is a disorder of cell growth and behaviour, so its ultimate cause has to be defined at the cellular and subcellular levels. The focus of this review is on the danger of microwave ovens as a major source of free radicals in food, which then eventually leads to cellular inflammation, cancer initiation, and cancer progression. Man-made microwave and radiofrequency radiation technologies have been steadily increasing with the growing demand for electronic appliances such as microwave oven. Research have shown that these appliances affect biological systems by increasing free radicals formation, thus leading to oxidative damage. Cancer is a multistage disease which includes initiation, promotion, and progression. Free radicals in the form of ROS and ORF usually lead to cellular inflammation. Free radicals also lead to DNA damage, gene mutation, and mitochondrial damage. Food prepared or heated in microwave ovens are a major source of free radicals. Hence, the need for people to reduce or totally stop the usage of microwave ovens, especially those already diagnosed with cancer disease. Various research findings support the clinical observations of the author as it relates to the causes and management of cancer disease. The findings also confirm anecdotal evidences on the link between cancer disease and the usage of microwave ovens.

Diamond-based quantum sensing of free radicals in migrating human breast cancer cells

Cell migration is a crucial parameter for disease progression in cancer. Reactive oxygen species (ROS) levels are involved in the regulation of the migration process, however, the exact role of free radical generation and where it occurs is unknown. Here we use a diamond-based quantum sensing technique to detect free radicals during cancer cell migration in real time with subcellular resolution. We investigated metastatic MDA-MB-231 human breast cancer cells and observed free radical formation after 16 h of starvation and 24 h of migration under low-serum conditions. Intracellular diamond dynamics were monitored at different migration points (0, 12, and 24 h), and cell morphology was evaluated. Additionally, the number of focal adhesions was analyzed as an indicator of the migratory potential of the cells. We further measured free radical generation under nicotinamide adenine dinucleotide phosphate hydrogen NADPH oxidases 2 (NOX2) inhibition by apocynin. We found that free radical levels decreased after 24 h treatment with 36 μg/mL apocynin while the levels of ROS and the migratory capacity of the cells increased. Our results evidence the complexity of the redox regulation in migrating cancer cells and offer a novel approach to specifically and locally interrogate pivotal players of the oxidative network behind metastatic success.

Formation of persistent free radicals from epigallocatechin Gallate in tea processing and their implications on DNA damage and cell cytotoxicity

Tea is widely consumed in both beverages and food. Epigallocatechin gallate (EGCG) is the most crucial active ingredient in tea. Currently, knowledges on transformation processes of EGCG during tea processing are lacking. Understanding the chemical reactions of EGCG and its products during tea processing is important for assessing the safety of tea-containing food. Here, we revealed the formation of persistent free radicals (PFRs) from EGCG under the influence of heating and light irradiation, which was substantiated with evidence. These PFRs exhibited stability for >30 min in simulated gastric fluid. Furthermore, we observed potential effects of these PFRs on DNA damage and cell cytotoxicity in vitro. By combining electron paramagnetic resonance spectrometer with Fourier transform ion cyclotron resonance mass spectrometry, we elucidated the pathways involved in free radical formation. These findings are expected to contribute to a comprehensive understanding of free radical chemistry in tea-containing food.

Sustainable photoelectrocatalytic oxidation of antibiotics using Ag–CoFe2O4@TiO2 heteronanostructures for eco-friendly wastewater remediation

Developing high-performance and durable catalysts presents a significant challenge for oxidizing toxic inorganic and pharmaceutical compounds in wastewater. Recently, there has been a surge in the development of new heterogeneous catalysts for degrading pharmaceutical compounds, driven by advancements in electrocatalysts and photoelectrocatalysts. In this study, a plasmonic Ag nanoparticles decorated CoFe2O4@TiO2 heteronanostructures have been successfully designed to fabricate a high-performing photoelectrode for the oxidation of pharmaceutical compounds. The developed Ag–CoFe2O4@TiO2 possessed a higher electrochemical stability and effectively harvested the UV to visible and NIR radiation in sunlight which generates the enormous photochemical reactive species that involved in the oxidation of ibuprofen in wastewater. Under direct sunlight irradiation, Ag–CoFe2O4@TiO2 achieved complete oxidation of ibuprofen in wastewater at 0.8 V vs RHE. This indicates that metallic Ag nanoparticles are involved in the charge separation and transport of charge carriers from the photoactive sites of CoFe2O4@TiO2, promoting the generation of abundant hydroxy, oxy, and superoxide radicals that actively break the bonds of ibuprofen. Additionally, oxidation agents such as urea and H2O2 were utilized to enhance the formation of superoxide ions and hydroxyl radicals, which rapidly participate in the oxidation of ibuprofen. Significantly, testing for recyclability confirmed the stability of the Ag–CoFe2O4@TiO2 photoanode, ensuring its suitability for prolonged use in photoelectrochemical advanced oxidation processes. Integrating Ag–CoFe2O4@TiO2 photoanodes into water purification systems could enhance economic feasibility, reduce energy consumption, and improve efficiency.

Effects of Nitrosyl Iron Complexes with Thiol, Phosphate, and Thiosulfate Ligands on Hemoglobin.

Nitrosyl iron complexes are remarkably multifactorial pharmacological agents. These compounds have been proven to be particularly effective in treating cardiovascular and oncological diseases. We evaluated and compared the antioxidant activity of tetranitrosyl iron complexes (TNICs) with thiosulfate ligands and dinitrosyl iron complexes (DNICs) with glutathione (DNIC-GS) or phosphate (DNIC-PO4-) ligands in hemoglobin-containing systems. The studied effects included the production of free radical intermediates during hemoglobin (Hb) oxidation by tert-butyl hydroperoxide, oxidative modification of Hb, and antioxidant properties of nitrosyl iron complexes. Measuring luminol chemiluminescence revealed that the antioxidant effect of TNICs was higher compared to DNIC-PO4-. DNIC-GS either did not exhibit antioxidant activity or exerted prooxidant effects at certain concentrations, which might have resulted from thiyl radical formation. TNICs and DNIC-PO4- efficiently protected the Hb heme group from decomposition by organic hydroperoxides. DNIC-GS did not exert any protective effects on the heme group; however, it abolished oxoferrylHb generation. TNICs inhibited the formation of Hb multimeric forms more efficiently than DNICs. Thus, TNICs had more pronounced antioxidant activity than DNICs in Hb-containing systems.

Photodynamic and Antibacterial Assessment of Gold Nanoparticles Mediated by Gold (III) Chloride Trihydrate and Sodium Citrate under Alkaline Conditions.

Sodium citrate (SC) is sensitive to violet light illumination (VLI) and acts as a weak reductant. Conversely, gold (III) chloride trihydrate (GC) often acts as an oxidant in a redox reaction. In this study, the influences of colored light on the production of gold nanoparticles (AuNPs) in a mixture of gold (III) ions and citrate via VLI and the antibacterial photodynamic inactivation (aPDI) of Escherichia coli (E. coli) are determined under alkaline conditions. The diameter of AuNPs is within the range of 3-15 nm, i.e., their mean diameter is 9 nm; when citrate is mixed with gold (III) ions under VLI, AuNPs are formed via an electron transfer process. Additionally, GC mixed with SC (GCSC) inhibits E. coli more effectively under VLI than it does under blue, green, or red light. GCSC and SC are shown to inhibit E. coli populations by 4.67 and 1.12 logs, respectively, via VLI at 10 W/m2 for 60 min under alkaline conditions. GCSC-treated E. coli has a more significant photolytic effect on anionic superoxide radical (O2•-) formation under VLI, as more O2•- is formed within E. coli if the GCSC-treated samples are subjected to VLI. The O2•- exhibits a greater effect in a solution of GCSC than that shown by SC alone under VLI treatment. Gold (III) ions in a GCSC system appear to act as an oxidant by facilitating the electron transfer from citrate under VLI and the formation of AuNPs and O2•- via GCSC photolysis under alkaline conditions. As such, the photolysis of GCSC under VLI is a useful process that can be applied to aPDI.

Insight into stable, concentrated radicals from sulfur-functionalized alkyne-rich crystalline frameworks and application in solar-to-vapor conversion

Organic radicals feature versatile unpaired electrons key for photoelectronic and biomedical applications but remain difficult to access in stable concentrated forms. We disclose easy generation of stable, concentrated radicals from various alkynyl phenyl motifs, including 1) sulfur-functionalized alkyne-rich organic linkers in crystalline frameworks; 2) the powders of these molecules alone; 3) simple diethynylbenzenes. For Zr-based framework, the generation of radical-rich crystalline framework was achieved by thermal annealing in the range of 300–450 °C. For terminal alkynes, electron paramagnetic resonance signals (EPR, indicative of free radicals) arise after air exposure or mild heating (e.g., 70 °C). Further heating (e.g., 150 °C for 3 h) raises the radical concentrations up to 3.30 mol kg−1. For more stable internal alkynes, transformations into porous radical solids can also be triggered, albeit at higher temperatures (e.g., 250–500 °C). The resulted radical-containing solids are porous, stable to air as well as heat (up to 300–450 °C) and exhibit photothermal conversion and solar-driven water evaporation capacity. The formation of radicals can be ascribed to extensive alkyne cyclizations, forming defects, dangling bonds and the associated radicals stabilized by polycyclic π-systems.

Visible light triggers the formation of reactive oxygen species in monoclonal antibody formulations

Most monoclonal antibody formulations require the presence of a surfactant, such as polysorbate, to ensure protein stability. The presence of high concentrations of polysorbate have been shown to enhance photooxidation of certain protein drug products when exposed to visible light. The current literature, however, suggest that photooxidation of polysorbate only occurs when exposed to visible light in combination with UVA light. This is probable as peroxides present in polysorbate solutions can be cleaved homolytically in the UVA region. In the visible region, photooxidation is not expected to occur as cleavage of peroxides is not expected at these wavelengths.This report presents findings suggesting that the presence of one or more photosensitiser(s) in polysorbate must be a cause and is required to catalyse the aerobic oxidation of polysorbate solutions upon exposure to visible light. Our investigation aimed to clarify the mechanism(s) of polysorbate photooxidation and explore the kinetics and the identity of the generated radicals and their impact on monoclonal antibody (mAb) degradation. Our study reveals that when polysorbate solutions are exposed to visible light between 400 - 800 nm in the absence of proteins, discolouration, radical formation, and oxygen depletion occur. We discuss the initial formation of reactive species, most likely occurring directly after reaction of molecular oxygen, with the presence of a triplet state photosensitiser, which is generated by intersystem crossing of the excited singlet state. When comparing the photooxidation of PS20 and PS80 in varying quality grades, we propose that singlet oxygen possesses potential for reacting with unsaturated fatty acids in PS80HP, however, PS20HP itself exhibited no measurable oxidation under the tested conditions. The study’s final part delves into the photooxidation behaviour of different PS grades, examining its influence on the integrity of a mAb in the formulation. Finally, we examined the effect of photooxidation on the integrity of monoclonal antibodies. Our findings show that the exposure to visible light in polysorbate-containing mAb solutions at high PS concentrations of 4 mg·ml−1 results in increased monoclonal antibody degradation, highlighting the need for cautious evaluation of the correct PS concentration to stabilise protein therapeutics.

Kinetic and thermodynamic behavior of co-pyrolysis of olive pomace and thermoplastic waste via thermogravimetric analysis

This work represents the first attempt to analyze kinetics, thermodynamics and reaction mechanism of olive pomace (OP) and waste plastic materials (PM) co-pyrolysis. Among PM, polypropylene (PP), polystyrene (PS), high density polypropylene (HDPE), polyvinyl chloride (PVC) and poly (ethylene terephthalate) glycol (PETG) were selected. Non-isothermal TG experiments were carried out under inert conditions at four heating rates, namely 5, 10, 20 and 40 °C/min. The kinetic triplet for raw materials and their blends was determined using Starink, Kissinger-Akahira-Sunose and Ozawa-Flynn-Wall iso-conversional models. Pyrolysis mechanism reactions were explained by diverse models, depending on thermal degradation progress. Results shown that co-pyrolysis followed a complex multi-step reaction mechanism. A synergistic effect was detected during co-pyrolysis of OP/PM mixtures. The addition of 50 % (w/w) OP biomass to PM waste decreased the energy of activation (Ea) from 50 to 25 % for all blends, except for PVC/OP. Thermodynamic analysis reveals that adding OP generally reduces the energy barrier (ΔH), except for PS-OP, and improves energy efficiency (ΔG) by facilitating radical formation and molecular chain cleavage.As a conclusion, this study may open up new avenues for waste valorization and resource recovery. Thus, it may contribute to the transition towards a circular and sustainable economy, through zero waste goal.

ANALYSIS OF ANTIOXIDANT SYSTEM OF TEST ANIMALS IN THE DYNAMICS OF THE WOUND PROCESS AT LOCAL APPLICATION OF HYDROGEL DRESSINGS

Introduction. The development of the inflammatory process is always accompanied by the activation of lipid peroxidation, which is caused by tissue hypoxia. This, in turn, catalyzes a change in the physiological parameters of the antioxidant system. The aim of the study is to analyze the dynamics of the antioxidant balance of wounds in an experiment using hydrogels saturated with silver ions and an antioxidant drug for the local treatment of inflammatory processes. Object and research methods. The experimental study was carried out on 80 Wistar rats weighing 150 to 200 grams. Animals were removed from the experiment. for 3, 7, 10, 14 days. Catalase activity in the dynamics of the wound process was determined. Research results and their discussion. The content of catalase on the 7th day in the third experimental group is 0.51±0.03 μKat/l. On the 10th day, the indicator of the antioxidant system in the second (0.44±0.05 μKat/l) and third experimental groups was 0.42±0.02 μKat/l. At the final stage of the study on the 14th day, the analysis of catalase content showed that in all animals with a simulated inflammatory process, the indicator of antioxidant activity had no significant differences between themselves and, importantly, with the indicators of intact animals (0.33±0.01 μKat /l). The indicators of the control (0.33±0.04 μKat/l) and experimental groups were as follows: the first experimental group – 0.32±0.06, the second experimental group – 0.36±0.04, the third experimental group – 0, 38±0.06 μKat/l. Antioxidant protection was supplemented by local release of a drug with antioxidant action from the hydrogels, which contributed to a reduction in the intensity of free radical oxidation processes. That is, in almost all groups of animals, which were simulated purulent-inflammatory wounds, indicators of catalase activity approached the level of intact animals already on the 14th day. Conclusions. Application for local treatment of hydrogel bandages saturated with an antioxidant drug, which is released into the wound surface for a long time, promotes the activation of antioxidant protection and suppresses the processes of free radical formation.

Ontology of the serpent

In this article, the author animates a different kind of telling and knowing for critical scholarship. Recognizing an unknowable reality through a journey to a mythical past, the author imagines an ontology of the serpent, a radical interdisciplinary, incantation for the future. This sorcerous evocation re-animates ancient mythical practices, forging a becoming that has not been realized. The serpent rejects a Christian, Cartesian, and modernist telos, recasting a different relationship with hierarchies that subvert radical forms of resistance from emerging. This paper ends within the embrace of anarchism, evoking the anarchist’s “No!”, destabilizing self and pointing toward wonderous, cosmic connections.

Importance of Polarizable Embedding for Absorption Spectrum Calculations of Arabidopsis thaliana Cryptochrome 1.

Cryptochromes are essential flavoproteins for circadian rhythms and avian magnetoreception. Flavin adenine dinucleotide (FAD), a chromophore within cryptochromes, absorbs blue light, initiating electron transfer processes that lead to a biological signaling cascade. A key step in this cascade is the formation of the FAD semiquinone radical (FADH•), characterized through a specific red-light absorption. The absorption spectra of FADH• in cryptochromes are, however, significantly different from those recorded for the cofactor in solution, primarily due to protein-induced shifts in the absorption peaks. This study employs a multiscale approach, combining molecular dynamics (MD) simulations with quantum mechanical/molecular mechanical (QM/MM) methodologies, to investigate the influence of protein dynamics on embedded FADH• absorption. We emphasize the role of the protein's polarizable environment in the shaping of the absorption spectrum, crucial for accurate spectral predictions in cryptochromes. Our findings provide valuable insights into the absorption process, advancing our understanding of cryptochrome functioning.

Review on the interaction mechanism of nitrogen/sulfur pollutants during fuel combustion

Abstract The formation and control of pollutants emitted from fuel combustion have always been a focal point in combustion chemistry. Key pollutants primarily include nitrogen oxides (NOx) and sulfur oxides (SOx), making it crucial to elucidate the formation processes of nitrogen and sulfur components during combustion for pollutant control. Due to the highly coupled evolution processes of both components, independent reaction mechanisms struggle to describe this process, thus considering the interactions between them is significant for the evolution of nitrogen and sulfur components. This paper investigates the promotional or inhibitory effects between nitrogen and sulfur components in fuel combustion experiments, with the magnitude of this interactive effect varying between 2% and 250%, contingent upon the equivalence ratio and the N/S ratio impacts. Additionally, from a microkinetic perspective, two mechanisms underlying N/S interactions are identified: direct and indirect interactions. Direct interaction involves the formation of NS radicals, primarily through direct reactions of nitrogen species (NOx/HCN/NHi, where i ranges from 0 to 3) with sulfur constituents (SOx/H2S). Conversely, indirect interaction alters the radical pool via the intervention of NO or SO2, subsequently influencing each other's reaction pathways. It is noted that the current reaction system is incomplete, lacking key reactions, while the kinetic parameters of some reactions are still contentious. Advanced theoretical calculations are needed to refine the N/S interaction reaction model, in order to provide more accurate predictions for nitrogen and sulfur pollutant levels.

Fenomena Globalize the Intifada di Tengah Genosida Warga Palestina

In the recesses of the Palestine-Israel conflict which continues to metamorphose, the Intifada movement has become a symbol of resistance to occupation and oppression which curbs the aspirations of the Palestinian people. However, in this era of increasingly connected globalization, the dynamics of this movement are experiencing a significant transformation, which challenges traditional paradigms and brings new challenges that affect both parties. With major challenges such as perceived injustice and political instability, resolving this conflict has the potential to reduce extremism and increase stability in the Middle East, so this study will explore how the Palestinian Intifada influenced conflict resolution efforts with the aim of understanding the essence of the Intifada movement which is often seen as a form of extremism and radicalization, and this study will also explore the transformation of the Palestinian Intifada into a global phenomenon, considering its impact on conflict dynamics and practical approaches to achieving sustainable and stable peace in the region.

Exposure to O3 and NO2 on the interfacial chemistry of the pulmonary surfactant and the mechanism of lung oxidative damage

Exposure to ozone (O3) and nitrogen dioxide (NO2) are related to pulmonary dysfunctions and various lung diseases, but the underlying biochemical mechanisms remain uncertain. Herein, the effect of inhalable oxidizing gas pollutants on the pulmonary surfactant (PS, extracted from porcine lungs), a mixture of active lipids and proteins that plays an important role in maintaining normal respiratory mechanics, is investigated in terms of the interfacial chemistry using in-vitro experiments; and the oxidative stress induced by oxidizing gases in the simulated lung fluid (SLF) supplemented with the PS is explored. The results showed that O3 and NO2 individually increased the surface tension of the PS and reduced its foaming ability; this was accompanied by the surface pressure-area isotherms of the PS monolayers shifting toward lower molecular areas, with O3 exhibiting more severe effects than NO2. Moreover, both O3 and NO2 produced reactive oxygen species (ROS) resulting in lipid peroxidation and protein damage to the PS. The formation of superoxide radicals (O2•–) was correlated with the decomposition of O3 and the reactions of O3 and NO2 with antioxidants in the SLF. These radicals, in the presence of antioxidants, led to the formation of hydrogen peroxide and hydroxyl radicals (•OH). Additionally, the direct oxidation of unsaturated lipids by O3 and NO2 further caused an increase in the ROS content. This change in the ROS chemistry and increased •OH production tentatively explain how inhalable oxidizing gases lead to oxidative stress and adverse health effects. In summary, our results indicated that inhaled O3 and NO2 exposure can significantly alter the interfacial properties of the PS, oxidize its active ingredients, and induce ROS formation in the SLF. The results of this study provide a basis for the elucidation of the potential hazards of inhaled oxidizing gas pollutants in the human respiratory system.