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1.
Nanomicro Lett ; 16(1): 143, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38436834

RESUMO

Despite the promising potential of transition metal oxides (TMOs) as capacitive deionization (CDI) electrodes, the actual capacity of TMOs electrodes for sodium storage is significantly lower than the theoretical capacity, posing a major obstacle. Herein, we prepared the kinetically favorable ZnxNi1 - xO electrode in situ growth on carbon felt (ZnxNi1 - xO@CF) through constraining the rate of OH- generation in the hydrothermal method. ZnxNi1 - xO@CF exhibited a high-density hierarchical nanosheet structure with three-dimensional open pores, benefitting the ion transport/electron transfer. And tuning the moderate amount of redox-inert Zn-doping can enhance surface electroactive sites, actual activity of redox-active Ni species, and lower adsorption energy, promoting the adsorption kinetic and thermodynamic of the Zn0.2Ni0.8O@CF. Benefitting from the kinetic-thermodynamic facilitation mechanism, Zn0.2Ni0.8O@CF achieved ultrahigh desalination capacity (128.9 mgNaCl g-1), ultra-low energy consumption (0.164 kW h kgNaCl-1), high salt removal rate (1.21 mgNaCl g-1 min-1), and good cyclability. The thermodynamic facilitation and Na+ intercalation mechanism of Zn0.2Ni0.8O@CF are identified by the density functional theory calculations and electrochemical quartz crystal microbalance with dissipation monitoring, respectively. This research provides new insights into controlling electrochemically favorable morphology and demonstrates that Zn-doping, which is redox-inert, is essential for enhancing the electrochemical performance of CDI electrodes.

2.
Water Res ; 251: 121099, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38184914

RESUMO

The escalation of global eutrophication has significantly increased due to the impact of climate change, particularly the increased frequency of extreme rainfall events. Predicting and managing eutrophication requires understanding the consequences of precipitation events on algal dynamics. Here, we assessed the influence of precipitation events throughout the year on nutrient and phytoplankton dynamics in a drinking water reservoir from January 2020 to January 2022. Four distinct precipitation patterns, namely early spring flood rain (THX), Plum rain (MY), Typhoon rain (TF), and Dry season (DS), were identified based on rainfall intensity, duration time, and cumulative rainfall. The study findings indicate that rainfall is the primary driver of algal dynamics by altering nutrient levels and TN:TP ratios during wet seasons, while water temperature becomes more critical during the Dry season. Combining precipitation characteristics with the lag periods between algal proliferation and rainfall occurrence is essential for accurately assessing the impact of rainfall on algal blooms. The highest algae proliferation occurred approximately 20 and 30 days after the peak rainfall during the MY and DS periods, respectively. This was influenced by the intensity and cumulative precipitation. The reservoir exhibited two distinct TN/TP ratio stages, with average values of 52 and 19, respectively. These stages were determined by various forms of nitrogen and phosphorus in rainfall-driven inflows and were associated with shifts from Bacillariophyta-dominated to Cyanophyta-dominated blooms during the MY and DS seasons. Our findings underscore the interconnected effects of nutrients, temperature, and hydrological conditions driven by diverse rainfall patterns in shaping algal dynamics. This study provides valuable insights into forecasting algal bloom risks in the context of climate change and developing sustainable strategies for lake or reservoir restoration.


Assuntos
Cianobactérias , Água Potável , Fitoplâncton , Água Potável/análise , Eutrofização , Lagos/análise , Fósforo/análise , Nutrientes/análise , China , Monitoramento Ambiental , Estações do Ano , Nitrogênio/análise
3.
Plant J ; 118(1): 90-105, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38113332

RESUMO

Necrotrophic fungal plant pathogens employ cell death-inducing proteins (CDIPs) to facilitate infection. However, the specific CDIPs and their mechanisms in pathogenic processes of Sclerotinia sclerotiorum, a necrotrophic pathogen that causes disease in many economically important crop species, have not yet been clearly defined. This study found that S. sclerotiorum secretes SsXyl2, a glycosyl hydrolase family 11 xylanase, at the late stage of hyphal infection. SsXyl2 targets the apoplast of host plants to induce cell death independent of xylanase activity. Targeted disruption of SsXyl2 leads to serious impairment of virulence, which can be recovered by a catalytically impaired SsXyl2 variant, thus supporting the critical role of cell death-inducing activity of SsXyl2 in establishing successful colonization of S. sclerotiorum. Remarkably, infection by S. sclerotiorum induces the accumulation of Nicotiana benthamiana hypersensitive-induced reaction protein 2 (NbHIR2). NbHIR2 interacts with SsXyl2 at the plasma membrane and promotes its localization to the cell membrane and cell death-inducing activity. Furthermore, gene-edited mutants of NbHIR2 displayed increased resistance to the wild-type strain of S. sclerotiorum, but not to the SsXyl2-deletion strain. Hence, SsXyl2 acts as a CDIP that manipulates host cell physiology by interacting with hypersensitive induced reaction protein to facilitate colonization by S. sclerotiorum. These findings provide valuable insights into the pathogenic mechanisms of CDIPs in necrotrophic pathogens and lead to a more promising approach for breeding resistant crops against S. sclerotiorum.


Assuntos
Ascomicetos , Melhoramento Vegetal , Plantas , Virulência , Tabaco , Morte Celular , Doenças das Plantas/microbiologia
4.
Environ Sci Pollut Res Int ; 30(56): 119343-119355, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37924400

RESUMO

The heterogeneous catalytic reduction of Cr(VI) to Cr(III) is an effective strategy for aqueous Cr(VI) contamination abatement, which requires the development of highly efficient, low-cost, and recyclable catalysts. Herein, Ni2P/N-doped biocarbon composites (Ni2P/N-BC) were fabricated through an anoxic pyrolysis process using NaCl and KCl as activators. A precursor of yeast biomass provided the essential C, N, and P elements for Ni2P/N-BC formation. When adopted for Cr(VI) reduction in the presence of oxalic acid as a reductant, the fabricated Ni2P/N-BC performed superior catalytic activity with a 100% Cr(VI) reduction efficiency within 10 min (Ni2P/N-BC-5 = 0.2 g L-1, oxalic acid = 0.4 g L-1, Cr(VI) = 20 mg L-1). Typical affecting parameters, e.g., catalyst dosage, oxalic acid loading, reaction temperature, initial solution pH, and water matrix, were investigated. Ni2P/N-BC exhibited good applicability in a broad pH range from 3.0 to 9.0 and in actual aquatic systems. Cr(VI) reduction efficiency remained 92.7% after five recycle runs. Such promising catalytic activity may originate from the well-crystallized Ni2P, N-doped biocarbon framework and high specific surface area of the materials. Preliminary reaction mechanism analysis indicated that the favorable charge state of Ni2P, fast hydrogen transfer, affinity of oxalic acid to Cr(VI), and inherent electron transfer in the biocarbon matrix contributed to effective Cr(VI) reduction. This work not only provides a facile and low-cost strategy to construct Ni2P/N-doped biocarbon nanosheet composite using environmentally benign biomass but also brings new insights for the remediation of Cr(VI) contamination.


Assuntos
Saccharomyces cerevisiae , Poluentes Químicos da Água , Biomassa , Cromo , Ácido Oxálico
5.
Food Chem Toxicol ; 179: 113936, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37429407

RESUMO

Zearalenone is a mycotoxin that is widely present in feed and raw materials and can cause severe reproductive toxicity. Lycopene is a natural carotenoid with antioxidant and anti-inflammatory pharmacological effects, but the protective effects of lycopene against zearalenone-induced uterine damage have not been reported. The aim of this study was to investigate the protective effect of lycopene treatment in early pregnancy on zearalenone-induced uterine damage and pregnancy impairment and its mechanism. Reproductive toxicity was induced by consecutive gavages of zearalenone at 5 mg/kg body weight during gestational days (GDs) 0-10 and in the presence or absence of oral administration of lycopene (20 mg/kg BW). The results showed that lycopene may alleviate zearalenone-induced pathological uterine histological damage and disturbances in oestradiol (E2), follicle-stimulating hormone (FSH), progesterone (P) and luteinizing hormone (LH) secretion. Lycopene increased superoxide dismutase (SOD) activity and decreased malondialdehyde (MDA) production, providing protection against zearalenone-induced oxidative stress in the uterus. Additionally, lycopene significantly reduced levels of pro-inflammatory cytokines, including interleukin 1ß (IL-1ß), interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α), and elevated levels of the anti-inflammatory factor interleukin 10 (IL-10), inhibiting the zearalenone-induced inflammatory response. In addition, lycopene improved the homeostasis of uterine cell proliferation and death via the mitochondrial apoptosis pathway. These data provide strong evidence that lycopene can be further developed into a potential new drug for the prevention or treatment of zearalenone-induced reproductive toxicity.


Assuntos
Antioxidantes , Zearalenona , Gravidez , Feminino , Humanos , Antioxidantes/farmacologia , Licopeno/farmacologia , Zearalenona/toxicidade , Carotenoides/farmacologia , Estresse Oxidativo , Anti-Inflamatórios/farmacologia , Interleucina-6/metabolismo
7.
Sci Rep ; 13(1): 9314, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37291198

RESUMO

As a basic building block of graphene-based materials, graphene oxide (GO) plays an important role in scientific research and industrial applications. At present, numerous methods have been employed to synthesize GO, there are still some issues that need to be solved, thus it is of importance to develop a green, safe and low-cost GO preparation method. Herein, a green, safe and fast method was designed to prepare GO, namely, graphite powder was firstly oxidized in a dilute sulfuric acid solution (H2SO4, 6 mol/L) with hydrogen peroxide (H2O2, 30 wt%) as oxidant, and then exfoliated to GO by ultrasonic treatment in water. In this process, H2O2 was the only oxidant, and no other oxidants were used, thus the explosive nature of GO preparation reaction in the conventional methods could be completely eliminated. This method has other advantages such as green, fast, low-cost and no Mn-based residues. The experimental results confirm that obtained GO with oxygen-containing groups has better adsorption property compared to the graphite powder. As adsorbent, GO can remove methylene blue (50 mg/L) and Cd2+ (56.2 mg/L) from water with removal capacity of 23.8 mg/g and 24.7 mg/g, respectively. It provides a green, fast and low-cost method to prepare GO for some applications such as adsorbent.


Assuntos
Grafite , Poluentes Químicos da Água , Grafite/química , Peróxido de Hidrogênio , Pós , Água , Oxidantes , Adsorção , Poluentes Químicos da Água/química , Cinética
8.
Sci Total Environ ; 888: 164240, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37201836

RESUMO

Many studies have demonstrated that climate change affects the biogeochemical cycle of pollutants, but the mechanisms of arsenic (As) biogeochemical processes under high CO2 levels are unknown. Here, rice pot experiments were carried out to explore the underlying mechanisms of the impacts of elevated CO2 on the reduction and methylation processes of As in paddy soils. The results revealed that elevated CO2 might increase As bioavailability and promote As(V)-to-As(III) transformation in the soil as well as higher As(III) and dimethyl arsenate (DMA) accumulation in rice grains, thus increasing health risk. In As-contaminated paddy soil, two key genes involved in the biotransformation of As (arsC and arsM) and associated host microbes were identified as being significantly promoted by increasing CO2 levels. Elevated CO2 enriched the soil microbes harboring arsC (Bradyrhizobiaceae and Gallionellaceae), which aided in the reduction of As(V) to As(III). Simultaneously, elevated CO2 enriched soil microbes harboring arsM (Methylobacteriaceae and Geobacteraceae), allowing As(V) to be reduced to As(III) and then methylated to DMA. The findings of the Incremental Lifetime Cancer Risk (ILTR) assessment suggested that elevated CO2 exacerbated the individual adult ILTR from rice food As(III) consumption by 9.0 % (p < 0.05). These findings show that elevated CO2 aggravates the exposure risk of As(III) and DMA in rice grains by changing microbial populations involved in As biotransformation in paddy soils.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Arsênio/análise , Metilação , Solo , Dióxido de Carbono/metabolismo , Oryza/metabolismo , Poluentes do Solo/análise
9.
Environ Pollut ; 327: 121586, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37044253

RESUMO

Metal-free carbon catalysts perform well in peroxymonosulfate-based advanced oxidation process for the treatment of organic pollutant-containing wastewater. Herein, a natural biomolecule of adenosine triphosphate (ATP), containing abundant N and P elements, served as sole precursor to prepare N,P-co-doped carbon through one-step anoxic pyrolysis, which was applied as peroxymonosulfate activator to treat bisphenol-contaminated water. Owing to the endogenous N and P elements in ATP, in-situ doping was achieved for the prepared carbon material with excellent doping effect, such as high doping amount and numerous defects. During pyrolysis process, the generated gases facilitated the exfoliation of carbon structure, resulting in a nanosheet-like morphology with large specific surface area, e.g., 852.75 m2 g-1 for NPCN-900 sample obtained at 900 °C. Benefiting from the structural modulation brought by N,P co-doping, typical sample of NPCN-900 presented excellent catalytic performance towards bisphenol AF (BPAF) degradation through PMS activation. An apparent reaction rate constant of 0.4115 min-1 was calculated under the investigated reaction conditions. Further studies indicated that 1O2, surface-bound •OH and SO4-• worked together in NPCN-900/PMS system for BPAF degradation. Graphitic N, pyrrolic N, CO groups, defect structure and the doped P atoms in NPCN-900 contributed to PMS activation. It was also important that the toxicity of BPAF solution could be preliminarily eliminated after treatment by NPCN-900/PMS system, which was verified by ecotoxicity assessments through ECOSAR program and green algae growth experiments.


Assuntos
Carbono , Poluentes Ambientais , Carbono/química , Água , Peróxidos/química
10.
Environ Pollut ; 324: 121396, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36871748

RESUMO

Rising atmospheric carbon dioxide (CO2) and soil heavy metal pollution, which affects safe rice production and soil ecosystem stability, have caused widespread concern. In this study, we evaluated the effects of elevated CO2 on Cd and Pb accumulation in rice plants (Oryza sativa L.), Cd and Pb bioavailability, and soil bacterial communities in Cd-Pb co-contaminated paddy soils via rice pot experiments. We showed that elevated CO2 accelerates the accumulation of Cd and Pb in rice grains by 48.4-75.4% and 20.5-39.1%, respectively. Elevated CO2 levels decreased soil pH value by 0.2 units, which increased Cd and Pb bioavailability in soil but inhibited iron plaque formation on rice roots, ultimately promoting Cd and Pb uptake. 16S rRNA sequencing analysis revealed that elevated CO2 increased the relative abundance of certain soil bacteria (e.g., Acidobacteria, Alphaproteobacteria, Holophagae, and Burkholderiaceae). A health risk assessment showed that elevated CO2 markedly increased the total carcinogenic risk values for children, adult males, and adult females by 75.3% (P < 0.05), 65.6% (P < 0.05), and 71.1% (P < 0.05), respectively. These results demonstrate the serious performance of elevated CO2 levels in accelerating the bioavailability and accumulation of Cd and Pb in paddy soil-rice ecosystems, with particular risks for future safe rice production.


Assuntos
Oryza , Poluentes do Solo , Criança , Humanos , Solo , Cádmio/análise , Ecossistema , Dióxido de Carbono/análise , Chumbo/análise , Disponibilidade Biológica , RNA Ribossômico 16S/genética , Poluentes do Solo/análise
11.
Artigo em Inglês | MEDLINE | ID: mdl-36726526

RESUMO

Background: Panax ginseng C. A. Mey (ginseng) is a traditional Chinese medicinal herb used for the treatment of nervous system disorders, such as Alzheimer's disease (AD). However, the pharmacological mechanisms of ginseng involved in AD have not been systematically investigated. Here, a network pharmacology approach was adopted to explore the effective components, core targets, and key pathways of ginseng against AD. Methods: TCMSP database was used to screen the active ingredients of ginseng. Prediction of the targets of ginseng and AD-related genes was performed using online public databases. "Compound-Target," "Compound-Target-Disease," "Protein-Protein Interaction (PPI)," "Compound-Target-Pathway," and "Compound-Target-GO-Pathway" networks were constructed with Cytoscape 3.7.2 software. Gene Ontology (GO) function annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were performed by using the DAVID database. Results: A total of 22 bioactive compounds were identified from ginseng, and 481 targets of ginseng and 763 AD-related targets were obtained from public databases. The PPI network screened out 19 hub genes of ginseng against AD. According to GO function enrichment, ginseng influenced cell proliferation, death, the nitric oxide biosynthetic process, hypoxia response, and synaptic transmission. Neuroactive ligand-receptor interaction, serotonergic synapse, calcium signaling, cAMP signaling, FoxO signaling, Ras signaling, and PI3K-AKT signaling were among the most key regulatory pathways. The compound-target-GO-route network found EGFR, MAPK1, MAPK14, AKT1, CASP3, and PRKACA as key genes, with PI3K-AKT signaling being the most important pathway for ginseng's anti-AD activity. Conclusion: Ginseng exerts neuroprotective effects in AD patients through multicomponent, multitarget, and multipathway modes, providing novel insight into the pharmacological and experimental research on ginseng against AD.

12.
J Hazard Mater ; 449: 131049, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-36840987

RESUMO

Organophosphate esters (OPEs) waste is difficult to dispose effectively because of its stability and the potential risk of P element. In this study, taking one typical organic extractant of tributyl phosphate (TBP) as an example, we proposed a strategy to treat OPEs inspired by chemical looping combustion (CLC) technology-oxygen carrier immobilization process (OCIP), aiming at efficient TBP degradation and simultaneous P immobilization. Adopting Fe-Mn bimetallic oxide (FMBO) as oxygen carrier, an almost 100% P immobilization efficiency was achieved under recommended conditions which were obtained by response surface methodology. Meanwhile, gaseous products released from TBP degradation, e.g., non-methane hydrocarbon, was lower than the maximum allowable emission concentration limit. Further characterizations implied that P-species released from reaction process were mainly immobilized as stable inorganic forms of metaphosphate, phosphate and pyrophosphate. On the basis of identifying degradation intermediates, we proposed a possible degradation pathways. FMBO as an oxygen carrier provided sufficient oxygen molecules for flameless combustion of OCIP process. Electron paramagnetic resonance measurement confirmed the existence of oxygen vacancies on FMBO surface, which contributed to the formation of •O2-. Oxidation by oxygen molecules and •O2- attack resulted in the degradation and mineralization of TBP, with simultaneously achieving P stabilization.

13.
Environ Sci Pollut Res Int ; 30(17): 49733-49743, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36781664

RESUMO

Elevated CO2 levels threat the crop quality by altering the environmental behavior of heavy metals (HMs) in soils. In reality, multiple HMs often co-exist in field, while details regarding coexisting HMs migration in flooded soil at elevated CO2 levels remain unclear. A pot experiment in open-top chambers (CO2 at 400 and 600 µmol mol-1) was conducted to explore the uptake and transfer of cadmium (Cd) and lead (Pb) in water dropwort (Oenanthe javanica DC.) grown in flooded soils contaminated with Cd and Pb. Results showed that elevated CO2 significantly reduced soil pH, promoting the release of Cd and Pb (by 63.64-106.90% and 10.66-30.99%, respectively) into soil porewater. In the harvested O. javanica, elevated CO2 decreased the root uptake of Cd but promoted that of Pb. Further mechanism analysis showed that elevated CO2 promoted the formation of iron plaque on root surface by 44.60-139.57%, with lower adsorption capacity to HMs (0-34.93% and 63.61-67.69% for Cd and Pb, respectively). Meanwhile, Pb showed lower adsorbability in iron plaque but higher transfer capacity when compared with Cd. Ultimately, elevated CO2 increased the target hazard quotient values of Pb in O. javanica. These findings provide new insights on the effects of elevated CO2 on the transfer of coexisting HMs in soil-plant system, and the risk of HMs pollution under climate changes needs to be more fully assessed.


Assuntos
Metais Pesados , Poluentes do Solo , Cádmio/análise , Verduras , Dióxido de Carbono/análise , Chumbo/análise , Solo , Metais Pesados/análise , Ferro/análise , Poluentes do Solo/análise
14.
Stem Cell Res ; 66: 102999, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36535090

RESUMO

Using peripheral blood mononuclear cell (PBMC) reprogramming technology, a human-induced pluripotent stem cell (iPSC) line was produced from a patient who presents classic clinical features of arrhythmogenic right ventricular cardiomyopathy (ARVA) and carries a de novo laminin subunit alpha 2 (LAMA2) heterozygous mutation (NM_000426.3: c.8842G > A, p.G2948S). This mutation was not inherited from his parents, who also present normal cardiac phenotype. This iPSC line demonstrates a normal karyotype. Pluripotency and differentiation capacity has been confirmed in vitro. This cell line can help in efforts to understand the pathogenic mechanism between LAMA2 mutation and ARVC.


Assuntos
Células-Tronco Pluripotentes Induzidas , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Leucócitos Mononucleares , Mutação/genética , Linhagem Celular , Diferenciação Celular
15.
Sci Total Environ ; 860: 160519, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36442636

RESUMO

Climate warming has profoundly altered the status of permafrost and has caused extensive permafrost degradation in the Northern Hemisphere. However, long-term observations investigating the hydrological dynamics of permafrost and its ecological effects on plant growth are lacking. Previous studies have reported tree-ring stable hydrogen isotope ratios of lignin methoxy groups (δ2HLM) as an archive of hydrological signals. This study sampled tree-ring cores from a Larix gmelinii forest in Nanwenghe Forest Park, Northeastern China, and separately measured the tree-ring δ2HLM for earlywood and latewood from 1900 to 2020. Earlywood and latewood δ2HLM values, as well as the difference between them, showed no significant long-term trend from 1900 to 1987; however, they both exhibited significant increasing trends since 1988 at rates of 2.6 ‰ and 4.9 ‰ per decade, respectively. This variance changes the magnitude of the difference between the two chronologies and can be explained by the shift in source water δ2H values during tree growth. Based on a structural equation model analysis, when the influence of permafrost melting weakened due to permafrost degradation, the growing season temperature was better recorded in latewood δ2HLM through the effects of precipitation δ2H from July to September. Based on the environmental response of tree-ring δ2HLM in the permafrost region, permafrost degradation influences the source water δ2H values of trees, thereby affecting the expression of temperature signals in tree-ring δ2HLM. The novel results in this study provide a new perspective on permafrost degradation based on the dynamic responses of tree-ring δ2HLM to source water δ2H during permafrost degradation.


Assuntos
Pergelissolo , Árvores , Lignina , Florestas , Água
16.
Chemosphere ; 313: 137562, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36526142

RESUMO

Peroxymonosulfate (PMS) activation-based advanced oxidation technology possesses great potential for antibiotic-containing wastewater treatment. Herein, we developed an iron phosphide/carbon composite and verified its capability and superiority towards a model antibiotic pollutant (sulfathiazole, STZ) degradation through PMS activation. Benefiting from the chelating ability of phytic acid (PA) with metal ions and its abundance on phosphorous element, a PA-Fe3+ complex was firstly formed and then served as sole precursor for iron phosphide formation by anoxic pyrolysis. Well crystalized FeP particle were found loading on the simultaneously formed thin layer carbon structure. Catalytic activity evaluation showed that FeP/carbon composite could remove over 99% of STZ (20 mg L-1) in 20 min adsorption and 30 min catalysis process under the reaction conditions of catalyst dosage 0.2 g L-1, PMS loading 0.15 g L-1. A pseudo-first-order reaction rate constant of 0.2193 min-1 was obtained, which was among the highest compared with reported studies. Further investigations indicated that the developed FeP/carbon composite worked well in a wide solution pH range of 3-9. Reaction mechanism study showed that reactive species of SO4-• and 1O2 generated from PMS activation played major roles for STZ degradation. Based on liquid chromatography-mass spectroscopy (LC-MS) analysis, a few STZ degradation intermediate products were identified, which facilitated the proposal of STZ degradation pathways. The possible ecological risk of STZ and related degradation intermediates were also considered by toxicity assessment using the Ecological Structure Activity Relationships (ECOSAR) Class Program. The obtained acute and chronic toxicity values implied the relatively low ecological risk of FeP/carbon-PMS reaction system for STZ treatment.


Assuntos
Carbono , Ácido Fítico , Carbono/química , Antibacterianos , Ferro , Sulfatiazol
17.
Sci Total Environ ; 863: 160831, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36526183

RESUMO

The occurrence and development of antibiotic resistance genes (ARGs) in pathogens poses serious threatens to global health. Agricultural soils provide reservoirs for pathogens and ARGs, closely related to public health and food safety. Especially, metals stress provides more long-standing selection pressure for ARGs, and climate change is a "threat multiplier" for the spread of ARGs. However, little is known about the impact of metals contamination on pathogens and ARGs in agricultural soils and their sensitivity to ongoing climate changes. To fill this gap, a pot experiment was conducted in open-top chambers (OTCs) to investigate the influence of mercury (Hg) contamination on the distribution of soil pathogens and ARGs under ambient and elevated CO2 concentration. Results showed that the relative abundance of common plant and human pathogens increased significantly in Hg-contaminated soil under two CO2 concentrations. Hg contamination was a positive effector of the activation of efflux pumps and offensive virulence factors (adhere and secretion system) under two CO2 levels. Activation of efflux pumps caused by Hg contamination might contribute to changes of virulence or fitness of certain pathogens. Overall, our study emphasizes the critical role of efflux pumps as an intersection of antibiotic resistance and pathogen's virulence under Hg stress.


Assuntos
Mercúrio , Humanos , Mercúrio/toxicidade , Dióxido de Carbono , Virulência , Resistência Microbiana a Medicamentos/genética , Solo , Antibacterianos/farmacologia , Genes Bacterianos , Microbiologia do Solo
18.
Angew Chem Int Ed Engl ; 62(1): e202215594, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36342503

RESUMO

The effect of proton transfer on water oxidation has hardly been measurably established in heterogeneous electrocatalysts. Herein, two isomorphous manganese phosphates (NH4 MnPO4 ⋅ H2 O and KMnPO4 ⋅ H2 O) were designed to form an ideal platform to study the effect of proton transfer on water oxidation. The hydrogen-bonding network in NH4 MnPO4 ⋅ H2 O has been proven to be solely responsible for its better activity. The differences of the proton transfer kinetics in the two materials indicate a fast proton hopping transfer process with a low activation energy in NH4 MnPO4 ⋅ H2 O. In addition, the hydrogen-bonding network can effectively promote the proton transfer between adjacent Mn sites and further stabilize the MnIII -OH intermediates. The faster proton transfer results in a higher proportion of zeroth-order in [H+ ] for OER. Thus, proton transfer-affected electrocatalytic water oxidation has been measurably observed to bring detailed insights into the mechanism of water oxidation.

19.
J Voice ; 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36526508

RESUMO

OBJECTIVE: This study aimed to explore the clinical efficacy of the microsuture technique combined with voice therapy in patients with Reinke's edema. METHODS: 46 patients with Reinke's edema admitted between April 2017 and August 2021 were selected and randomly divided into simple surgical and combined therapy groups. The simple surgical and combined therapy group were evaluated preoperatively and at 3 months after surgery using subjective and objective voice analysis. RESULTS: Compared with the preoperative state, there was a significant improvement in the acoustic parameters 3 months postoperatively. The G and R scores, Voice Handicap index-10 (VHI-10), and jitter parameters of the combined therapy group were lower, whereas F0 and maximum phonation time (MPT), changed significantly in the combined therapy group, fundamental frequency perturbation (jitter), and MPT acoustic parameters of the combined therapy group were lower than those of the simple surgery group (P < 0.05). CONCLUSION: The microsuture technique is preferable for eliminating vocal folds surgical wounds and promoting mucosal recovery, and combined with voice therapy is more helpful to comprehensive improve the quality of phonation.

20.
Front Chem ; 10: 962528, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339050

RESUMO

MXenes and MXene-based composite materials have potential applications in a wide range of areas due to their unique physical and chemical characteristics. At present, it is still a major challenge to develop a simple, safe, and efficient route to prepare MXenes without using fluorinated etchants. Herein, we design a facile method to prepare Ti3C2Tx MXene sheets by selectively etching Ti3AlC2 powders in an aqueous diluted H2SO4 solution with H2O2 as an oxidant. In a system of H2SO4 and H2O2, an aqueous H2SO4 solution with a concentration of 6 mol/L is a strongly acidic medium with no volatility, and 30% H2O2 acts as a strong green oxidizer without harmful by-products. The experimental process is safe and convenient to conduct in a beaker under a water bath of 40°C. The etching process can be completed in 1 h under the air atmosphere conditions. The experimental results confirmed that the etched Ti3AlC2 powders can be successfully separated into Ti3C2Tx nanosheets under ultrasound treatment without using any intercalation agent. The relevant etching mechanism is may be attributed to the synergy effect of H2SO4 and H2O2, which triggers sequential selective etching of Al layers from the Ti3AlC2 phase. It may provide a new green way to prepare MXene-based materials without using toxic HF or HF-containing etchants.

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