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Coupling extra electron supply with iron-mediated advanced oxidation processes (AOPs) is an efficient strategy for long-lasting oxidation of organic contaminants in environmental remediation. Many subsequent attempts have been made, such as homogeneous catalysts and metal catalysts, of which secondary organic pollution and surface passivation layers limit their application. In this work, metal borides as co-catalysts can efficiently accelerate the Fenton reaction by firmly sacrificing electrons to Fe(III) reduction. Among multiple metallic borides, vanadium boride (VB 2 ) performs superiorly as dual active sites to solve the Fe(III) cycle dilemma and quickly generate hydroxyl radicals via Fenton reaction for almost completely eliminating almost carbamazepine (CBZ) in VB 2 /Fe(III)/H 2 O 2 . Characterization analysis and the density functional theory (DFT) calculation unveil that the synergistic effect of V and B on the surface of VB 2 makes Fe-O bonds of FeOH 2+ weaker (from 173.8 pm to 178.4 pm) to produce more active Fe(III) species. And meanwhile, active Fe(III) can be rapidly reduced into Fe(II) on the surface of VB 2 and then be completely released into solution for subsequent Fenton reaction and hydroxyl radical generation. More importantly, VB 2 performs steadily and efficiently for 7th consecutive test in VB 2 /Fe(III)/H 2 O 2 to degrade more than 95% CBZ, resulting from the self-cleaning surface of VB 2 to expose reactive regions for persistent electron sacrifice and sustainably stimulative Fenton oxidation. Therefore, this research offers the detailed fundamental perception into the genesis of VB 2 as well as a novel electron donor for boosting Fenton oxidation towards water remediation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Objectives: Whether there is an association between serum uric acid level (sUA) and periodontitis remains unclear. The aim of this study was to investigate the association between moderate/severe periodontitis and sUA in US adults., Materials and Methods: A total of 3398 participants were included in the National Health and Nutrition Examination Survey (NHANES) from 2009 to 2014. The independent variable was sUA and the dependent variable was periodontitis. SUA for continuous variables, periodontitis as classification variables. Covariate including social demographic variables, life style, systemic diseases, etc. Multiple linear regression models were used to investigate the distribution of differences in covariates between different independent groups. To investigate the association between serum uric acid levels and moderate/severe periodontitis, three models were used (Model 1: unadjusted model; Model 2: adjusted for age, sex, and race/ethnicity; Model 3: adjusted for age, sex, race/ethnicity, education, household income/poverty ratio, smoking behavior, alcohol consumption, dental floss frequency, obesity, hypertension, diabetes, high cholesterol, hyperlipidemia, and sleep disorders)., Results: Among the 3398 patients, 42.5% had moderate/severe periodontitis. Multivariate logistic regression analysis showed that sUA was significantly associated with moderate/severe periodontitis (OR = 1.10, 95%CI: (1.03, 1.16), P = 0.0020) after adjusting for potential confounding factors. In addition, it may vary by race/ethnicity and gender. The association between sUA levels and the prevalence ofperiodontitis was U-shaped in women and non-Hispanic blacks., Conclusion: sUA level is associated with moderate to severe periodontitis. However, the association between sUA levels and the occurrence of periodontitis in women and non-Hispanic blacks followed a U-shaped curve., Clinical Relevance: sUA may directly or indirectly contribute to the global burden of periodontal disease, but there is little evidence that sUA is directly related to periodontitis.This study further supports that high uric acid levels are closely related to periodontitis and may contribute to the control of periodontitis. It also provides new insights into whether it can be used as an indicator to assess the risk or progression of periodontitis. More studies are needed to confirm the relationship between sUA and periodontitis., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Bai et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Spatially confined structure exhibits surprising physics and chemistry properties that significantly impact the thermodynamics and kinetics of oxidation reactions. Herein, porous carbons are rationally designed for tunable nanopore structures (micropores, 4.12 % ∼ 91.64 %) and diverse spatial confinement ability, as indicated by their differential enhancement performances in the Fenton oxidation. Porous carbons can alter the characteristics of the charge transport process for accelerating sustainable electron shuttle between hydrogen peroxide and iron species, and thus exhibit long-term performance (17 cycling tests). The positive spatial confinement for boosting Fenton oxidation (charge transport, mass transfer) occurs in nanochannels < 1 nm, while the diminished effect ranges of 1-1.5 nm, and the adverse effect ranges greater than 1.5 nm. The density functional theory calculation provides further support for certifying the promoted charge transport process and spatial confinement for hydroxyl radical inside the confined nanochannel structure (below 1 nm, especially) by the comparatively large electron cloud and the relatively negative adsorption energy, respectively. Coupling nanochannels with the Fenton oxidation greatly utilize hydrogen peroxide, due to spatial nanoconfinement and selective adsorption towards target contaminants. This strategy of deploying nanochannels in catalyst design can be applied for the elaborate construction of efficient nanostructured catalysts for environmental remediation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Airborne transmission is among the most frequent types of nosocomial infection. Recent years have witnessed frequent outbreaks of airborne diseases, such as severe acute respiratory syndrome (SARS) in 2002, Middle East respiratory syndrome (MERS) in 2012, and coronavirus disease 2019 (COVID-19), with the latter being on the rampage since the end of 2019 and bringing the effect of aerosols on health back to the fore (Gralton et al., 2011; Wang et al., 2021). An increasing number of studies have shown that certain highly transmissible pathogens can maintain long-term stability and efficiently spread through aerosols (Leung, 2021; Lv et al., 2021). As reported previously, influenza viruses that can spread efficiently through aerosols remain stable for a longer period compared to those that cannot. The World Health Organization (WHO) has stated that aerosol-generating procedures (AGPs) play an important role in aerosol transmission in hospitals (Calderwood et al., 2021). AGPs, referring to medical procedures that produce aerosols, including dental procedures, endotracheal intubation, sputum aspiration, and laparoscopic surgeries, have been reported to be significantly associated with an increased risk of nosocomial infection among medical personnel (Hamilton, 2021).

Direct photoreduction of Fe III is a widely recognized route for accelerating Fe III /Fe II cycle in photo-Fenton chemistry. However, most of the wavelengths covering the full spectral range are insufficient to supply enough photon energy for the direct reduction process. Herein, the hitherto neglected mechanism of Fe III reduction that the Fe III indirect reduction pathway initiated by light energy-dependent reactivity variation and reactive excited state (ES) was explored. Evolution of excited-state Fe III species (*Fe III ) resulting from metal-centered charge excitation (MCCE) of Fe III is experimentally verified using pulsed laser femtosecond transient absorption spectroscopy with UV-vis detection and theoretically verified by quantum chemical calculation. Intense photoinduced intravalence charge transition was observed at λ = 380 and 466 nm, revealing quartet 4 MCCE and doublet 2 MCCE and their exponential processes. Light energy-dependent variation of *Fe III reactivity was kinetically certified by fitting the apparent rate constant of the radical-chain sequence of photo-Fenton reactions. Covalency is found to compensate for the intravalence charge separation following photoexcitation of the metal center in the MCCE state of Fenton photosensitizer. The *Fe III is established as a model, demonstrating the intravalence hole delocalization in the ES can be leveraged for photo-Fenton reaction or other photocatalytic schemes based on electron transfer chemistry.

Background: It is uncertain if mean platelet volume and periodontitis are related. The objective of this study was to examine the association between levels of mean platelet volume and moderate/severe periodontitis in adult persons who inhabit the U.S., Methods: We screened 6,809 people from the National Health and Nutrition Examination Survey (NHANES 2009-2012). Mean platelet volume was measured in the Mobile Examination Centers (MECs) using the Beckman Coulter analyzer. The category of periodontitis was defined by the CDC/AAP using clinical periodontal parameters. Multiple logistic regression models were employed to examine the distribution for covariate differences across the various independent groups. Four models were employed to examine the relationship between mean platelet volume level and periodontitis. Smoothed curve fitting was utilized to confirm the linearity of the relationships. To determine the impact of factors on the connection between MPV and periodontitis, subgroup analysis and interaction testing were utilized., Results: Results from the multiple logistic regression analysis indicate a significant association between moderate/severe periodontitis and the mean platelet level, even after considering any potential confounding variables (OR = 1.090, 95% CI: 1.019-1.166, P-value = 0.01211). Additionally, those in the upper tertile of mean platelet volume levels had a 21.6% higher probability of developing periodontitis when compared with those in the least tertile of mean platelet levels (OR = 1.216, 95% CI:1.052-1.406, P-value = 0.00816). Moreover, it showed a positive correlation between mean platelet volume (MPV) and moderate/severe periodontitis. Subgroup analyses indicated a positive association between the level of mean platelet volume and moderate/severe periodontitis among individuals who were under 60 years of age, had low income, were obese, never smoked, were heavy drinkers, had hypertension, and had no cardiovascular disease (p < 0.05). However, none of the subgroups exhibited significant interactions (p for interaction > 0.05)., Conclusion: A correlation has been found between mean platelet volume levels and periodontal disease in individuals residing in the United States., (© 2024. The Author(s).)

Metal-free carbon material-mediated nonradical oxidation processes (C-NOPs) have emerged as a research hotspot due to their excellent performance in selectively eliminating organic pollutants in aqueous environments. However, the selective oxidation mechanisms of C-NOPs remain obscure due to the diversity of organic pollutants and nonradical active species. Herein, quantitative structure-activity relationship (QSAR) models were employed to unveil the origins of C-NOP selectivity toward organic pollutants in different oxidant systems. QSAR analysis based on adsorption and oxidation descriptors revealed that C-NOP selectivity depends on the oxidation potentials of organic pollutants rather than on adsorption interactions. However, the dominance of electronic effects in selective oxidation decreases with increasing structural complexity of organic pollutants. Moreover, the oxidation threshold solely depends on the inherent electronic nature of organic pollutants and not on the reactivity of nonradical active species. Notably, the accuracy of substituent descriptors (Hammett constants) and theoretical descriptors (e.g., highest occupied molecular orbital energy, ionization potential, and single-electron oxidation potential) is significantly influenced by the complexity and molecular state of organic pollutants. Overall, the study findings reveal the origins of organic pollutant-oriented selective oxidation and provide insight into the application of descriptors in QSAR analysis.

The acceleration of Fe(III)/Fe(II) conversion in Fenton systems is the critical route to achieve the long-lasting generation of reactive oxygen species towards the oxidation of refractory contaminants. Here, we found that waste leather derived porous carbon materials (LPC), as a simple and readily available metal-free biochar material, can promote the Fe(III)/H 2 O 2 system to generate hydroxyl radicals ( • OH) for oxidizing a broad spectrum of contaminants. Results of characterizations, theoretical calculations, and electrochemical tests show that the surface carbonyl groups of LPC can provide electron for direct Fe(III) reduction. More importantly, the graphitic-N on surface of LPC can enhance the reactivity of Fe(III) for accelerating H 2 O 2 induced Fe(III) reduction. The presence of LPC accelerates the Fe(III)/Fe(II) redox cycle in the Fe(III)/H 2 O 2 system, sustainable Fenton chain reactions is thus initiated for long-lasting generation of hydroxyl radicals without adding Fe(II). The continuous flow mode that couples in-situ Fenton-like oxidation and LPC with excellent adsorption catalytic properties, anti-coexisting substances interference and reusability performance enables efficient, green and sustainable degradation of trace organic pollutants. Therefore, the application of metal-free carbon materials in Fenton-like system can solve its rate-limiting problem, reduce the production of iron sludge, achieve green Fenton chemistry, and facilitate the actual engineering application of economic and ecological methods to efficiently remove trace organic contaminants from actual water sources., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The continuous electron supply for oxidant decomposition-induced reactive oxygen species (ROS) generation is the main contributor for the long-standing micropollutant oxidation in the iron-based advanced oxidation processes (AOPs). Herein, as a new class of co-catalysts, metal borides with dual active sites and preeminent conductive performance can effectively overcome the inherent drawback of Fenton-like reactions by steadily donating electrons to inactive Fe(III). Among the metal borides, tungsten boride (WB) exhibits a significant co-catalytic performance run ahead of common heterogeneous co-catalysts and exceptionally high stability. Based on qualitative and semi-quantitative tests, the hydroxyl radical, sulfate radical, and iron(IV)-oxo complex are all produced in the WB/Fe(III)/PDS system and Fe(IV)-induced methyl phenyl sulfoxide decomposition is up to 72%. Moreover, the production efficiency of ROS and relative proportions of radical and nonradical pathways change with various experimental conditions (dosages of PDS, WB, and solution pH) and water matrices. The rate-determining step of Fe(II) regeneration is greatly accelerated resulting from the synergetic effect between exposed metallic reactive sites and nonmetallic boron with reductive properties of WB. In addition, the self-dissolution of surface tungsten oxide and boron oxide leads to a renovated surface for sustainable Fe(III) reduction in long-term operations. Our discovery provides an efficient and sustainable strategy in the field of enhanced AOPs for water remediation.

Accelerating the rate-limiting Fe 3+ /Fe 2+ circulation in Fenton reactions through the addition of reducing agents (or co-catalysts) stands out as one of the most promising technologies for rapid water decontamination. However, conventional reducing agents such as hydroxylamine and metal sulfides are greatly restricted by three intractable challenges: (1) self-quenching effects, (2) heavy metal dissolution, and (3) irreversible capacity decline. To this end, we, for the first time, introduced redox-active polymers as electron shuttles to expedite the Fe 3+ /Fe 2+ cycle and promote H 2 O 2 activation. The reduction of Fe 3+ mainly took place at active N-H or O-H bonds through a proton-coupled electron transfer process. As electron carriers, H atoms at the solid phase could effectively inhibit radical quenching, avoid metal dissolution, and maintain long-term reducing capacity via facile regeneration. Experimental and density functional theory (DFT) calculation results indicated that the activity of different polymers shows a volcano curve trend as a function of the energy barrier, highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) gap, and vertical ionization potential. Thanks to the appropriate redox ability, polyaniline outperforms other redox-active polymers (e.g., poypyrrole, hydroquinone resin, poly(2,6-diaminopyridine), and hexaazatrinaphthalene framework) with a highest iron reduction capacity up to 5.5 mmol/g, which corresponds to the state transformation from leucoemeraldine to emeraldine. Moreover, the proposed system exhibited high pollutant removal efficiency in a flow-through reactor for 8000 bed volumes without an obvious decline in performance. Overall, this work established a green and sustainable oxidation system, which offers great potential for practical organic wastewater remediation.

The regeneration of Fe(II) is the rate-limiting step in the Fenton/Fenton-like chain reactions that seriously hinder their scientific progress towards practical application. In this study, we proposed iron boride (FeB) for the first time as a new material to sustainably decompose H 2 O 2 to generate hydroxyl radicals, which can non-selectively degrade a wide array of refractory organic pollutants. Fe(II) can be steadily released by the stepwise oxidation of FeB to stimulate Fenton reaction, meanwhile, B-B bonds as electron donors on the surface of FeB effectively promote the regeneration of Fe(II) from Fe(III) species and significantly accelerate the production of hydroxyl radicals. The low generation of toxic by-products and the high utilization rate of iron species validly avoid the secondary organic/metal pollution in the FeB/H 2 O 2 system. Therefore, FeB mediated Fenton oxidation provides a novel strategy to realize a green and long-lasting environmental remediation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Reduction of Fe(III) is the rate-limiting step of iron induced Fenton-like systems, such as the iron/peroxydisulfate system, reducing agents (RAs) were frequently employed as electron donors to directly reduce Fe(III) to further promote the formation of reactive oxygen species (ROS), mainly including hydroxyl radical ( • OH), sulfate radical (SO 4 •- ), and ferryl ion (Fe(IV)). However, the intrinsic distinctions among these ROS cause the substrate specific reactivity towards oxidation of diverse organic contaminants. In this study, various RAs (representative solid amorphous boron (A-Boron) and dissolved hydroxylamine (HA)) were added to enhance the Fe(III)/PDS system for investigating the substrate specific reactivity of ROS. It is demonstrated that RAs remarkably boost the Fe(III)/Fe(II) cycles to produce • OH, SO 4 •- , and Fe(IV) in the RAs/Fe(III)/PDS systems, based on the results of EPR analysis, quenching tests, and chemical probe analysis. Furthermore, the different yields of methyl phenyl sulfone (PMSO 2 ) indicate that the distribution of multiple oxidizing species changed with various factors (i.e., type and dosage of RAs added, solution pH, Fe(III) and PDS dosage). This work provides the possibility for the adjustment of oxidation selectivity of RAs/Fe(III)/PDS systems by regulating contribution of radicals and non-radical for oxidizing organic contaminants due to the substrate specific reactivity of • OH, SO 4 •- , and Fe(IV), moreover, the comparison of homogeneous and heterogeneous RAs provides assistance in the application of RAs for environmental remediation., (Copyright © 2022. Published by Elsevier Ltd.)

The sluggish kinetics of Fe(II) recovery strongly impedes the scientific progress of Fenton reaction (Fe(II)/H 2 O 2 ) towards practical application. Here, we propose a novel mechanism that metal-free nitrogen-doped carbon nanotubes (NCNT) can enhance Fenton chemistry with H 2 O 2 as electron donors by elevating the oxidation potential of Fe(III). NCNT remarkably promotes the circulation of Fe(III)/Fe(II) to produce hydroxyl radical ( • OH) with excellent stability for multiple usages (more than 10 cycles) in the NCNT/Fe(III)/H 2 O 2 system. Although carbonyl on NCNT can act as the electron supplier for Fe(III) reduction, the behavior of NCNT is distinct from common reductants such as hydroxylamine and boron. Electrochemical analysis and density functional theory calculation unveil that nitrogen sites of NCNT can weakly bind with Fe(III) to elevate the oxidation potential of Fe(III) (named near-free Fe(III), primarily FeOH 2+ ) at pH ranging from 2.0 to 4.0. Without inputs of external stimulations or electron sacrificers, near-free Fe(III) can promote H 2 O 2 induced reduction of Fe(III) to initiate Fenton chain reactions for long-lasting generation of • OH. To our delight, it is a common property of N-doped carbon materials (e.g., graphene, carbon nanofibers, and acetylene black), our research thus provides a novel, sustainable, and green strategy for promoting Fenton chemistry., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Many reagents as electron sacrificers have been recently investigated to induce decomposition of permanganate (KMnO 4 ) to produce highly reactive intermediate Mn species toward oxidation of organic contaminants; however, this strategy meanwhile causes low KMnO 4 utilization efficiency. This study surprisingly found that graphite can mediate direct electron transfer from organics (e.g., sulfamethoxazole (SMX)) to KMnO 4 , resulting in high KMnO 4 utilization efficiency, rather than reductive sites of graphite-induced conversion of KMnO 4 to highly reactive intermediate Mn species. The galvanic oxidation process (GOP) and comparative experiments of different organic contaminants prove that the KMnO 4 /graphite system mainly extracts electrons from organic contaminants via a one-electron pathway instead of a two-electron pathway. More importantly, the KMnO 4 /graphite system has superior reusability, graphite can keep a long-lasting reactivity, and the KMnO 4 utilization efficiency elevates significantly after each cycle of graphite. The transformation of SMX in the KMnO 4 /graphite system mainly includes self-coupling, hydroxylation, oxidation, and hydrolytic reaction. The work will improve insights into the electron-transfer mechanism and unveil the advantages of efficient KMnO 4 utilization in the KMnO 4 -based technologies in environmental remediation.

Single-atom catalysts (SACs) have attracted considerable attention from researchers because of their distinct structures and characteristics, especially in maximizing atomic utilization and elevating the intrinsic catalytic activity. More recently, SACs have been becoming a burgeoning area of the environmental field and are extensively applied to remove various refractory organic pollutants. This review summarizes the emerging synthetic and characterization strategies of SACs and analyzes their development tendency. Besides, the application of SACs in advanced oxidation processes (AOPs, e.g., catalysis of H 2 O 2 , activation of persulfates and photocatalysis) is discussed. The excellent removal of pollutants depends on the fast generation of reactive oxygen species (SO 4 •- , • OH, 1 O 2 , and O 2 •- ). The advantages of SACs in AOPs are summarized, and constructive opinions are put forward for the stability and activity of the catalyst. Finally, the opportunities and challenges faced by SACs and its future development direction in the AOPs catalytic field are proposed., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Unlike the other studies on emotional design in multimedia learning, the present study differentiated the two confounding variables of visual interface design and structured content to manipulate the instructional material. Specifically, we investigated how the visual aesthetics of positive emotional interface design influenced learners' cognitive processes, emotional valences, learning outcomes, and subjective experience. Eighty-one college students took part in the experimental study. They were divided into the three experimental groups: a holistic layout of positive emotional design group (HPED), a local layout of positive emotional design group (LPED), and a neutral emotional design group (ND). By using a mixed approach of questionnaires and eye tracking, we further explored the differences among the three groups in cognitive processing, learning outcomes, and subjective experience. Results indicated that the LPED group invested higher cognitive effort, put more attentional focus in the relevant knowledge content module, and achieved better learning performance (i.e., retention and transfer tests) in contrast to the HPED group and the ND group. However, no significant difference in dynamic changes of emotional state among the three groups was detected. The analytical results can provide researchers and practitioners with valuable insights into the positive emotional design of multimedia learning, which allows for the facilitation of mental engagement, learning outcomes and subjective perception., Competing Interests: Competing interestsThe authors declared no potential competing interests with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2021.)

Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.