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Alcohols are promising fuels for direct alcohol fuel cells and are common scavengers to identify reactive oxygen species (ROS) in electro-Fenton (EF) systems. However, the side impacts of alcohols on oxygen reduction reactions and ROS generation are controversial due to the complex interactions between electrodes and alcohol-containing electrolytes. Herein, we employed synchrotron-Fourier-transform infrared spectroscopy and electron paramagnetic resonance technologies to directly observe the changes of chemical species and electrochemical properties on the electrode surface. Our studies suggested that alcohols exhibited different limiting degrees on proton (H+) mass transfer toward the catalytic surface, following an order of methanol < ethanol < isopropanol < tert-butyl alcohol (TBA). In addition, the formation of hydrophobic TBA clusters at high concentrations (>400 mM) resulted in a significant reduction in ionic conductivity and an elevation in charge transfer resistance, which impedes H+ mass transfer and raises the energy barrier for 2e- oxygen reduction reaction processes. Moreover, the organic radical â¢CH2(CH3)2CH2OH produced by the interaction of Fe3+ and â¢OH with the alcohol in the EF system serves as a crucial intermediate in facilitating H2O2 regeneration, which complicates the quenching effect of alcohols on â¢OH identification. Therefore, it is recommended that methanol should be used as the scavenger instead of TBA and the concentration should be less than 400 mM in EF systems.
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Álcoois , Peróxido de Hidrogênio , Peróxido de Hidrogênio/química , Álcoois/química , Oxirredução , Ferro/química , Espécies Reativas de Oxigênio/químicaRESUMO
Single atom catalysts (SACs) are atomic-level-engineered materials with high intrinsic activity. Catalytic centers of SACs are typically the transition metal (TM)-nonmetal coordination sites, while the functions of coexisting non-TM-bonded functionalities are usually overlooked in catalysis. Herein, the scalable preparation of carbon-supported cobalt-anchored SACs (CoCN) with controlled CoâN sites and free functional N species is reported. The role of metal- and nonmetal-bonded functionalities in the SACs for peroxymonosulfate (PMS)-driven Fenton-like reactions is first systematically studied, revealing their contribution to performance improvement and pathway steering. Experiments and computations demonstrate that the CoâN3C coordination plays a vital role in the formation of a surface-confined PMS* complex to trigger the electron transfer pathway and promote kinetics because of the optimized electronic state of Co centers, while the nonmetal-coordinated graphitic N sites act as preferable pollutant adsorption sites and additional PMS activation sites to accelerate electron transfer. Synergistically, CoCN exhibits ultrahigh activity in PMS activation for p-hydroxybenzoic acid oxidation, achieving complete degradation within 10 min with an ultrahigh turnover frequency of 0.38 min-1, surpassing most reported materials. These findings offer new insights into the versatile functions of N species in SACs and inspire rational design of high-performance catalysts in complicated heterogeneous systems.
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BACKGROUND: Preschooling is a critical time for intervention in children with autism spectrum disorder (ASD); thus, we analyzed brain tissue component volumes (BTCVs) and clinical indicators in preschool children with ASD to identify new biomarkers for early screening. METHODS: Eighty preschool children (3-6 years) with ASD were retrospectively included. The whole-brain myelin content (MyC), white matter (WM), gray matter (GM), cerebrospinal fluid (CSF), and non-WM/GM/MyC/CSF brain component volumes were obtained using synthetic magnetic resonance imaging (SyMRI). Clinical data, such as intelligence scores, autism diagnostic observation schedule-calibrated severity scores, age at first production of single words (AFSW), age at first production of phrases (AFP), and age at walking onset (AWO), were also collected. The correlation between the BTCV and clinical data was evaluated, and the effect of BTCVs on clinical data was assessed by a regression model. RESULTS: WM and GM volumes were positively correlated with intelligence scores (both P < 0.001), but WM and GM did not affect intelligence scores (P = 0.116, P = 0.290). AWO was positively correlated with AFSW and AFP (both P < 0.001). The multivariate linear regression analysis revealed that MyC, AFSW, AFP, and AWO were significantly different (P = 0.005, P < 0.001, P < 0.001). CONCLUSIONS: This study revealed positive correlations between WM and GM volumes and intelligence scores. Whole-brain MyC affected AFSW, AFP, and AWO in preschool children with ASD. Noninvasive quantification of BTCVs via SyMRI revealed a new visualizable and quantifiable biomarker (abnormal MyC) for early ASD screening in preschool children.
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Biochar (BC) is a new type of carbon material with a high specific surface area, porous structure, and good adsorption capacity, which can effectively adsorb and enrich organic pollutants. Meanwhile, nano zero-valent iron (nZVI) has excellent catalytic activity and can rapidly degrade organic pollutants through reduction and oxidation reactions. The combined utilization of BC and nZVI can not only give full play to their advantages in the adsorption and catalytic degradation of organic pollutants, but also help to reduce the agglomeration of nZVI, thus improving its efficiency in water treatment and providing strong technical support for water resources protection and environmental quality improvement. This article provides a detailed introduction to the preparation method and characterization technology, reaction mechanism, influencing factors, and specific applications of BC and nZVI, and elaborates on the research progress of BC-nZVI in activating persulfate (PS) to degrade organic pollutants in water. It has been proven experimentally that BC-nZVI can effectively remove phenols, dyes, pesticides, and other organic pollutants. Meanwhile, in response to the existing problems in current research, this article proposes future research directions and challenges, and summarizes the application prospects and development trends of BC-nZVI in water treatment. In summary, BC-nZVI-activated PS is an efficient technology for degrading organic pollutants in water, providing an effective solution for protecting water resources and improving environmental quality, and has significant application value.
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Nowadays, antibiotics are widely used, increasing the risk of contamination of the water body and further threatening human health. The traditional water treatment process is less efficient in degrading antibiotics, and the advanced oxidation process (AOPs) is cleaner and more efficient than the traditional biochemical degradation process. The combined ozone/peroxymonosulfate (PMS) advanced oxidation process (O3/PMS) based on sulfate radical (SO4â¢-) and hydroxyl radical (â¢OH) has developed rapidly in recent years. The O3/PMS process has become one of the most effective ways to treat antibiotic wastewater. The reaction mechanism of O3/PMS was reviewed in this paper, and the research and application progress of the O3/PMS process in the degradation of antibiotics in drinking water and wastewater effluent were evaluated. The operation characteristics and current application range of the process were summarized, which has a certain reference value for further research on O3/PMS process.
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Água Potável , Ozônio , Poluentes Químicos da Água , Purificação da Água , Humanos , Águas Residuárias , Antibacterianos , Poluentes Químicos da Água/análise , Peróxidos , OxirreduçãoRESUMO
Water pollution induced by antibiotics has garnered considerable concern, necessitating urgent and effective removal methods. This study focused on exploring ciprofloxacin (CIP) removal by duckweed and assessing CIP bioaccumulation and toxic effects within duckweed under varying dissolved organic matter categories, pH levels, and nutrient (nitrogen (N) and phosphorus (P)) levels. The results revealed the proficient and rapid elimination of CIP from water by duckweed, resulting in 86.17 % to 92.82 % removal efficiency at the end of the 7-day experiment. Across all exposure groups, varying degrees of CIP bioaccumulation in duckweed were evident, with uptake established as a primary pathway for CIP elimination within this plant. Additionally, five CIP metabolites were identified in duckweed tissues. Interestingly, the presence of humic acid (HA) and fulvic acid (FA) reduced CIP absorption by duckweed, with FA yielding a more pronounced impact. Optimal CIP removal was recorded at a pH of 7.5, while duckweed displayed heightened physiological stress induced by CIP at pH 8.5. Although the influence of N and P concentrations on CIP removal by duckweed was modest, excessive N and P levels intensified the physiological strain of CIP on duckweed.
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Araceae , Poluentes Químicos da Água , Ciprofloxacina/toxicidade , Ciprofloxacina/análise , Matéria Orgânica Dissolvida , Bioacumulação , Poluentes Químicos da Água/toxicidade , Antibacterianos/toxicidade , Nutrientes , Araceae/metabolismo , Concentração de Íons de HidrogênioRESUMO
In recent years, there has been growing concern about antibiotic contamination in water bodies, particularly the widespread presence of fluoroquinolones (FQs), which pose a serious threat to ecosystems due to their extensive use and the phenomenon of "pseudo-persistence". This article provides a comprehensive review of the literature on FQs in water bodies, summarizing and analyzing contamination levels of FQs in global surface water over the past three years, as well as the bioaccumulation and metabolism patterns of FQs in aquatic organisms, their ecological toxicity, and the influencing factors. The results show that FQs contamination is widespread in surface water across the surveyed 32 countries, with ciprofloxacin and norfloxacin being the most heavy contaminants. Furthermore, contamination levels are generally higher in developing and developed countries. It has been observed that compound types, species, and environmental factors influence the bioaccumulation, metabolism, and toxicity of FQs in aquatic organisms. FQs tend to accumulate more in organisms with higher lipid content, and toxicity experiments have shown that FQs exhibit the highest toxicity to bacteria and the weakest toxicity to mollusk. This article summarizes and analyzes the current research status and shortcomings of FQs, providing guidance and theoretical support for future research directions.
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This study aimed to investigate the levels of 12 sulfonamide antibiotics in freshwater fish species obtained from three cities in northeastern China (Harbin, Changchun, and Shenyang). The analysis was conducted using HPLC-MS/MS to accurately quantify the antibiotic concentrations in the fish samples. The results showed that the average levels of sulfonamide antibiotics in fish samples from Harbin, Changchun, and Shenyang were 1.83 ng/g ww, 0.98 ng/g ww, and 1.60 ng/g ww, respectively. Sulfamethoxazole displayed the highest levels and detection rates in all three cities, whereas sulphapyridine exhibited the lowest concentrations in all the fish samples. The levels of sulfonamide antibiotic residues in the different fish species varied widely among the cities, and the highest level of antibiotic residues was found in the muscle of carnivorous fish. The results from a health risk evaluation on the consumption of these fish indicated that the risk from long-term antibiotic exposure to local residents from the intake of the sampled fish was small and not sufficient to pose a significant health risk to consumers.
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Tobacco (Nicotiana tabacum L.) is an important economic crop that is widely grown around the world. Its annual production in China is estimated at 2.2 million tons (Berbec and Matyka 2020). Since 2022, a root rot disease was sporadically observed on tobacco seedlings on cultivar Yunyan 87 in cultivated tobacco fields in the Hunan province of China. A disease incidence of about 10% occurred across 48 ha of tobacco fields. The affected tobacco plants had slow and stunted growth with yellowing leaves. The roots turned grayish brown, decayed, and died. Diseased roots were collected from six fields and cut into small pieces (5 mm ×5 mm) from the edge of the rotted portions, and then sterilized with 70% ethanol for 10 s, 0.1% HgCl2 for 1 min, and washed in sterilized water three times. All the sterilized tissue were placed on potato dextrose agar (PDA) medium and cultured at 26 â in the dark. About 3 days later, colonies with similar morphology were removed and sub-cultured on fresh PDA. A total of six strains were obtained from six tobacco samples. Strains were white and had radial growth on PDA. Hyphae were aseptate and the sporangia were filamentous. The oogonia were subglobose, smooth, 16.04 ± 0.25 µm (n=50) in diameter, and developed on unbranched stalks. The antheridia were barrel shaped and clavate. Oospores were globose, aplerotic or nearly plerotic, measuring 6.62 ± 0.33 µm (n=50). These morphological characteristics were consistent with the description of Pythium spp. (van der Plaats-Niterink 1981). For molecular identification, the internal transcribed spacer (ITS) region of rDNA and cytochrome c oxidase subunit I (Cox I) of a representative isolate, GF-3, were amplified and sequenced (GenBank accession nos. OR228424 for ITS and OR237556 for Cox I) using universal primers ITS1/ITS4 (White et al. 1990) and FM58/FM66, respectively (Villa et al. 2006). BLASTn analysis revealed that the ITS and Cox I sequences were 99.76 % (838/840 bp) and 99.85% (671/672 bp) identical to the corresponding sequences of P. dissotocum strain CBS 166.68 (AY598634.2) and UM982 (MT981147.1), respectively. A neighbor-joining phylogenetic tree based on the Cox I sequence showed that GF-3 grouped in the P. dissotocum branch. Based on morphological and molecular characteristics, GF-3 was identified to be P. dissotocum. For pathogenicity testing, four- to five-leaf-old healthy potted tobacco seedlings of the Yunyan 87 cultivar were inoculated with a zoospore suspension (1 × 105 zoospores/ml), which was induced on V8-juice medium. The zoospore suspension was introduced into the soil around plant roots and 10 mL of inoculum was used for each plant. In the control group, plants were inoculated with sterilized water. All of the treated plants were kept in humid chambers at 26°C under a 12 h/12 h photoperiod. The pathogenicity assays were performed twice, with each treatment having three replicated plants. After 5 days, tobacco seedlings inoculated with P. dissotocum showed symptoms resembling that observed in the field. However, the control plants remained healthy. Pythium dissotocum was re-isolated from the infected plants and identified by morphological and molecular methods, thus confirming Koch's postulates. Pythium dissotocum has been reported causing root rot in other plants, including hydroponic lettuce (McGehee et al. 2018) and spinach (Huo et al. 2020). Also, many Pythium species have recently been recovered from float-bed tobacco transplant production greenhouses (Zhang et al. 2022). However, to our knowledge, this is the first report of root rot on tobacco caused by P. dissotocum in China. Since this disease could greatly affect tobacco seedling establishment in the field, appropriate management strategies need to be developed to reduce further losses in tobacco planting fields.
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In recent years, the use of magnetic biochar in wastewater treatment has shown significant effects and attracted scholars' attention. However, due to the relatively short research time and the lack of systematic summaries, it is difficult to provide a more in-depth analysis. This study utilizes RStudio and CiteSpace software to comprehensively analyze the research trends and progress of magnetic biochar in wastewater treatment. The analysis of bibliometrics is performed on 551 relevant papers retrieved from the Web of Science, spanning the period between 2011 and 2022. The most influential countries, institutions, journals, disciplinary distribution, and top 10 authors and papers in this field have been identified. The latest dataset has been used for keyword clustering and burst analysis. The results indicated that: (1) Bin Gao is the most influential author in this field, and high-level journals such as Bioresource Technology are more inclined to publish articles in the field of magnetic biochar. (2) Research in this field has predominantly focused on the removal of heavy metals and organic compounds. Keyword burst analysis shows a shift in research direction towards the removal of complex organic pollutants recently. (3) For the future development of magnetic biochar, an environment-friendly approach, economic viability, and joint technology are the directions that need more exploration. Finally, this paper provides a summary of the various adsorption mechanisms of magnetic biochar and several common modification methods, aiming to assist scholars in their research endeavors.
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Poluentes Ambientais , Águas Residuárias , Fenômenos Físicos , Fenômenos MagnéticosRESUMO
Water, sediments, and biofilms are the typical microbial carriers in natural water environments. However, comparative analysis of the distribution of bacterial and fungal communities in different carriers within the same habitat is relatively lacking. Therefore, this study employed 16 S and ITS rRNA gene sequencing to identify bacterial and fungal community structures in water, sediments, and biofilm. The results show that (1) the OTUs numbers revealed that the bacterial abundance, at the levels of species, genus, and family, followed the order of sediments > water > biofilms, while the fungal abundance order was water > sediments > biofilms. In addition, bacteria were mainly present in sediments, while fungi were mainly present in water. (2) The α diversity index (Shannon, ACE, Simpson, and Chao1) order, for bacteria was: sediments > water > biofilms, indicating that the diversity and homogeneity of bacteria in sediments were relatively higher; for fungi was: water > sediments > biofilms, indicating that the diversity and abundance of fungi in water were high. (3) The core phylum of bacterial in the water, sediments, and biofilms was Cyanobacteria (31.3-46.1%) and Actinobacteria (27.6-36.1%); Proteobacteria (35.0-41.8%), Cyanobacteria (14.7-36.6%); and Proteobacteria (63.3-69.2%), respectively. (4) The mainly colonized fungal phyla in biofilms in the water, sediments, and biofilms were Basidiomycota (29.3-38.7%) and Ascomycota (16.2-27.7%); Zygomycota (13.1-17.5%), Basidiomycota (5.6-17.6%); and Zygomycota (23.8-44.2%). (5) There were significant species differences in bacterial and fungal communities in water, sediments, and biofilm by NMDS analysis. Findings are useful for guiding significance for the Biogeochemical cycle of elements, the environmental fate of pollutants, and the study of water ecosystems.
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Ascomicetos , Cianobactérias , Água , Ecossistema , Rios , Biofilmes , Fungos/genética , China , Sedimentos Geológicos/químicaRESUMO
Accelerating the rate-limiting Fe3+/Fe2+ 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 Fe3+/Fe2+ cycle and promote H2O2 activation. The reduction of Fe3+ 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.
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Peróxido de Hidrogênio , Ferro , Ferro/química , Peróxido de Hidrogênio/química , Substâncias Redutoras , Elétrons , OxirreduçãoRESUMO
Alternaria dianthicola is a pathogenic fungus that causes serious leaf or flower blight on some medicinal plants worldwide. In this study, multiple dsRNA bands in the range of 1.2-10 kbp were found in a Alternaria dianthus strain HNSZ-1, and eleven full-length cDNA sequences of these dsRNA were obtained by high-throughput sequencing, RT-PCR detection and conventional Sanger sequencing. Homology search and phylogenetic analyses indicated that the strain HNSZ-1 was infected by at least nine mycoviruses. Among the nine, five viruses were confirmed to represent novel viruses in the families Hypoviridae, Totiviridae, Mymonaviridae and a provisional family Ambiguiviridae. Virus elimination and horizontal transmission indicated that the (-) ssRNA virus, AdNSRV1, might be associated with the slow growth and irregular colony phenotype of the host fungus. As far as we know, this is the first report for virome characterization of A. dianthus, which might provide important insights for screening of mycovirus for biological control and for studying of the interactions between viruses or viruses and their host.
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Micovírus , Vírus de RNA , Alternaria/genética , DNA Complementar/genética , Micovírus/genética , Genoma Viral , Filogenia , Vírus de RNA/genética , RNA de Cadeia Dupla/genética , RNA Viral/genéticaRESUMO
BACKGROUND: The associations of physical activity with Alzheimer's disease (AD) pathologies remain controversial. OBJECTIVE: To quantitatively assess the association between the frequency of physical activity with cerebrospinal fluid (CSF) biomarkers in AD and further explore the mechanism by which AD pathologies regulate the correlation between physical activity and cognition. METHODS: A total of 918 participants without dementia from Chinese Alzheimer's Biomarker and Lifestyle (CABLE) were examined in this population-based cross-sectional study. Multiple linear models were used to evaluate the associations of physical activity with CSF biomarkers and cognition. Moreover, mediation analyses were conducted to investigate the potential relationships between physical activity, AD pathologies, and cognitive function. RESULTS: Regular physical activity was positively associated with CSF Aß42 (pâ<â0.001) and Aß42/40 (pâ<â0.001), while it was negatively associated with p-tau/Aß42 (pâ<â0.001) and t-tau/Aß42 (pâ<â0.001). Of all participants, regular physical activity was associated with increased cognitive function (pâ<â0.001). The interaction effect indicated that age moderated the association between physical activity frequency and CSF Aß42 (pâ=â0.014) and p-tau/Aß42 (pâ=â0.041). The impact of physical activity on cognition was mediated in part by amyloid pathologies, accounting for 4.87% to 21.56% of the total effect (pâ<â0.05). CONCLUSION: This study showed the beneficial impact of physical activity on AD pathologies and cognition in participants without dementia.
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Doença de Alzheimer , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Cognição/fisiologia , Estudos Transversais , Exercício Físico , Humanos , Estilo de Vida , Fragmentos de Peptídeos/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidianoRESUMO
For effective photocatalytic pollutant degradation on bismuth tungstate (Bi2WO6), it is vital to enhance the photogenerated charge separation and the photochemical stability. Herein, we successfully fabricated yttrium (Y)-Bi2WO6/graphene (G) nanocomposites with a significantly enhanced visible light-driven photocatalytic ability to degrade Rhodamine B compared with the bare Bi2WO6. This is attributed to the remarkably improved visible light absorption capability and photogenerated charge separation after doping yttrium and subsequent coupling with graphene, as revealed by photoluminescence and electrochemical impedance spectroscopies. Moreover, trapping experiments were carried out to clarify that photogenerated ·O2- and holes were the dominant oxidative species in the photocatalytic reaction. In addition, it was confirmed that the resulting composites maintained good photostability and chemical stability during recycling tests. Graphical abstract.
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Poluentes Ambientais , Bismuto , Catálise , Luz , OxirreduçãoRESUMO
The pathological changes caused by phenolic wastewater discharged from various industries has attracted extensive attention in recent years. In this study, a novel sulfate-radical-based advanced oxidation process (SR-AOP) was used to dispose the target pollutant - phenols. Firstly, a solid-phase active catalyst - cobalt ferrite (CoFe2O4) was prepared from a sol-gel process with the innovative addition of ascorbic acid (AA). Then the original AOP was modified by using a novel CoFe2O4/AA/PDS combined system (PDS: peroxydisulfate).CoFe2O4 was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and H-M magnetic hysteresis loops. The influence factors on degradation in the new system were determined. It was found the activated PDS (S2O82-) generated a strong oxidizer sulfate radical (SO4·) and the phenol removal process basically obeyed the pseudo-first-order kinetics. The phenol degradation rate maximized to 98.00% under the following optimal conditions: CoFe2O4 preparation temperature at 500°C, initial phenol concentration at 50.00â mg/L, PDS dosage of 4.20â mM, CoFe2O4 dosage of 1.00â gL-1, and AA dosage of 0.42â mM. The new system had a high phenol degradation performance in a wide range of pH 3-7.The easy oxidization of metal ion solutions in a homogeneous system and the application limitation of pH range were well solved. The synergistic effect of the novel CoFe2O4/AA/PDS combined system on activated PDS was verified. The separation and reuse of CoFe2O4 were improved owing to its magnetism. These findings will underlie the practical application of CoFe2O4 into disposal of phenol waste water.
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Águas Residuárias , Poluentes Químicos da Água , Ácido Ascórbico , Fenol , Fenóis , Poluentes Químicos da Água/análiseRESUMO
BACKGROUND: Children's flood risk perceptions that include their awareness and behaviors, can be cultivated through disaster education, which is crucial for improving disaster resilience and adaptation to climate extremes. However, education's co-influencing effect along with family and society was unclear. This study investigated a three-year disaster education program conducted in schools in Sichuan Province, China. METHOD: In three pilot counties, we used stratified cluster sampling in 2016 and 2018 to separately survey the risk perceptions of 2,105 children (baseline) and 1710 children (post-intervention), respectively, aged 8-12, in 45 primary schools. The Ordinary Least Squares Regression and Propensity Score Matching Method (PSM) were used to assess the effectiveness of classroom education, propaganda poster, professional guidance, social education (television, radio, friends, and internet), and risk-related parent-child interactions. Interaction items and Structure Equation Model (SEM) were performed to identify their co-influencing mechanisms. Finally, the intervention effect was assessed by categorizing different levels of parent-child interactions and left-behind status. RESULT: The classroom education (Coeff = 0.040; P < 0.05), propaganda poster (Coeff = 0.024; P < 0.05), and professional guidance (Coeff = 0.016; P < 0.1) had significantly positive effects on children's flood risk perception. But these effects were found to be underestimated using PSM. Interaction effects between disaster education and parent-child interaction were statistically significant, and parent-child interaction was a moderating factor for improving risk perception (standardized indirect effect = 0.055, p < 0.001). Additionally, the mean score of risk perception increased by 118% in 2018 compared with the baseline. It was found that the higher the level of risk-related parent-child interaction, the higher the mean scores of risk perception (Coeff = 0.055; P < 0.001) irrespective whether they are left-behind children. CONCLUSION: To improve disaster resilience and climate change adaptation, risk-related parent-child interaction should be considered in disaster education, which is an effective way to promote children's risk perceptions.
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Desastres , Inundações , Criança , China , Humanos , Percepção , PolíticasRESUMO
On March 1, 2012, the Chinese government implemented the Administrative Measures on Heatstroke Prevention (AMHP2012) to combat the occupational health impacts of extreme heat, and reducing occupational injury was one of the main purposes. This study aimed at quantifying the intervention effects of the AMHP2012 on extreme heat-related occupational injuries and subsequent insurance payouts in Guangzhou, China. Data on occupational injuries and insurance payouts were collected from March 1, 2011, to February 28, 2013, from the occupational injury insurance system of Guangzhou. A quasi-experimental design with before-after control was adopted. Interrupted time series analysis was performed to quantify the change of occupational injuries and insurance payouts after policy implementation. The distributed lag non-linear model was used to explore whether injury claims and insurance payouts due to extreme heat decreased. A total of 9851 injury claims were included in the analysis. After policy implementation, the risk of occupational injuries and insurance payouts decreased by 13% (RR = 0.87, 95%CI: 0.75, 0.99) and 24% (RR = 0.76, 95% CI: 0.58, 0.94), respectively. The attributable fraction of extreme heat-related occupational injuries decreased from 3.17% (95%eCI: 1.35, 4.69) to 1.52% (95%eCI: -0.36, 3.15), which contributed to 0.86 million USD reduction of insurance payouts. Both males and females, low-educated, young and middle-aged workers, workers at small or medium-sized enterprises, engaging in manufacturing, and with both minor and severe injuries were apparently associated with decreased rates of extreme heat-related occupational injuries. The AMHP2012 policy contributed to the reduction of extreme heat-related occupational injuries and insurance payouts in Guangzhou, China, and this research provided novel evidence for decision-makers to better understand the necessity of implementing health protection policies among laborers under climate change.
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Calor Extremo , Exposição Ocupacional , Traumatismos Ocupacionais , China/epidemiologia , Cidades , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Traumatismos Ocupacionais/epidemiologia , Traumatismos Ocupacionais/prevenção & controleRESUMO
BACKGROUND: Pyruvic acid (PA), a vital α-oxocarboxylic acid, plays an important role in energy and carbon metabolism. The oleaginous yeast Yarrowia lipolytica (Y. lipolytica) has considerable potential for the production of PA. An increased NaCl concentration reportedly increases the biomass and PA yield of Y. lipolytica. RESULTS: To increase the yield of PA, the NaCl-tolerant Y. lipolytica A4 mutant was produced using the atmospheric and room temperature plasma method of mutation. The A4 mutant showed growth on medium containing 160 g/L NaCl. The PA yield of the A4 mutant reached 97.2 g/L at 120 h (0.795 g/g glycerol) in a 20-L fermenter with glycerol as the sole carbon source, which was 28.9% higher than that of the parental strain. CONCLUSION: The PA yield from Y. lipolytica can be improved by increasing its NaCl tolerance.
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Ácido Pirúvico/metabolismo , Yarrowia/genética , Yarrowia/metabolismo , Pressão Osmótica , Leveduras , Carbono/metabolismo , Cloreto de Sódio , Reatores Biológicos , Tolerância ao Sal/genética , Fermentação , Glicerol/metabolismo , MutaçãoRESUMO
L-DOPA (L-dihydroxyphenylalanine) is a promising drug for Parkinson's disease and thereby has a growing annual demand. Tyrosine phenol-lyase (TPL)-based catalysis is considered to be a low-cost yet efficient route for biosynthesis of L-DOPA. TPL is a tetrameric enzyme that catalyzes the synthesis of L-DOPA from pyrocatechol, sodium pyruvate, and ammonium acetate. The implementation of TPL for L-DOPA production has been hampered and the need for the most efficient TPL source with higher L-DOPA production and substrate conversion rate is prevailing. This study involves identifying a novel TPL from Kluyvera intermedia (Ki-TPL) and displayed a robust expression in Escherichia coli. The recombinant strain YW000 carrying Ki-TPL proved strong catalytic activity with a highest L-DOPA yield compared with 16 other TPLs from different organisms. With a further aim to improve this efficiency, random mutagenesis of Ki-TPL was performed and a mutant namely YW021 was obtained. The whole cells of YW021 as biocatalyst yielded 150.4 g L-1 of L-DOPA with a 99.99 % of pyrocatechol conversion at the optimum condition of pH 8.0 at 25 °C, which is the highest level reported to date. Further, the homology modeling and structural analysis revealed the mutant residues responsible for the extensive L-DOPA biosynthesis.