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1.
Environ Sci Technol ; 58(37): 16282-16290, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39236339

RESUMO

To assess the ecological risk of microplastics (MPs) in agricultural systems, it is critical to simultaneously focus on MP-mediated single-organism response and different trophic-level organism interaction. Herein, we placed earthworms in soils contaminated with different concentrations (0.02% and 0.2% w/w) of polyethylene (PE) and polypropylene (PP) MPs to investigate the effect of earthworms on tomato against Helicoverpa armigera (H. armigera) under MPs stress. We found that earthworms alleviated the inhibitory effects of MPs stress on tomato growth and disrupted H. armigera growth. Compared to individual MPs exposure, earthworm incorporation significantly increased the silicon and lignin content in herbivore-damaged tomato leaves by 19.1% and 57.6%, respectively. Metabolites involved in chemical defense (chlorogenic acid) and phytohormones (jasmonic acid) were also activated by earthworm incorporation. Furthermore, earthworms effectively reduced oxidative damage induced by H. armigera via promoting antioxidant metabolism. Overall, our results suggest that utilizing earthworms to regulate above- and below-ground interactions could be a promising strategy for promoting green agriculture.


Assuntos
Microplásticos , Oligoquetos , Animais , Oligoquetos/fisiologia , Produtos Agrícolas , Insetos , Poluentes do Solo , Solanum lycopersicum
2.
Environ Sci Technol ; 58(2): 1010-1021, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-37934921

RESUMO

Despite the increasing prevalence of atmospheric nanoplastics (NPs), there remains limited research on their phytotoxicity, foliar absorption, and translocation in plants. In this study, we aimed to fill this knowledge gap by investigating the physiological effects of tomato leaves exposed to differently charged NPs and foliar absorption and translocation of NPs. We found that positively charged NPs caused more pronounced physiological effects, including growth inhibition, increased antioxidant enzyme activity, and altered gene expression and metabolite composition and even significantly changed the structure and composition of the phyllosphere microbial community. Also, differently charged NPs exhibited differential foliar absorption and translocation, with the positively charged NPs penetrating more into the leaves and dispersing uniformly within the mesophyll cells. Additionally, NPs absorbed by the leaves were able to translocate to the roots. These findings provide important insights into the interactions between atmospheric NPs and crop plants and demonstrate that NPs' accumulation in crops could negatively impact agricultural production and food safety.


Assuntos
Antioxidantes , Microplásticos
3.
J Sports Sci ; 42(6): 490-497, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38594887

RESUMO

This study compared performance strategies and sub-technique selection in cross-country skate skiing sprint races, specifically individual time-trial (ITT) and head-to-head (H2H) formats. Fourteen male cross-country skiers from the Chinese national team participated in the FIS-sanctioned sprint race day. GNSS and heart rate sensors recorded positioning, skiing speeds, heart rate, sub-technique usage, and skiing kinematics. Statistical parametric mapping (SPM) was used to determine the course positions (clusters) where instantaneous skiing speed was significantly associated with section time. One-way analyses of variance were used to examine differences between the ITT and H2H. H2H race speeds were 2.4 ± 0.2% faster than the ITT race (p < 0.05).Variations in sub-technique and skiing kinematics were observed between race formats, indicating different strategies and tactics employed by athletes. SPM identified specific clusters (primarily uphill) where the fastest athlete gained significant time over the slowest. The greatest time gains were associated with higher G3 sub-technique usage and longer G3 cycle length on steep uphill terrain (9-13% gradients). Integrating SPM analyses and sub-technique assessments can help optimise performance and tactics in sprint races. This study enhances our understanding of cross-country skiing dynamics and performance variations among elite competitors.


Assuntos
Desempenho Atlético , Comportamento Competitivo , Frequência Cardíaca , Esqui , Humanos , Esqui/fisiologia , Masculino , Desempenho Atlético/fisiologia , Fenômenos Biomecânicos , Frequência Cardíaca/fisiologia , Comportamento Competitivo/fisiologia , Adulto , Adulto Jovem , Sistemas de Informação Geográfica , China
4.
J Environ Manage ; 317: 115441, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35661879

RESUMO

Despite the fact that microplastic pollution in terrestrial ecosystems has received increasing attention, there are few studies on the potential effects of different microplastics on terrestrial plants. In this study, the toxicity of polystyrene (PS), polyethylene (PE) and polypropylene (PP) microplastics with different concentrations (0, 10, 100, 500 and 1000 mg/L) to tomato (Lycopersicon esculentum L.) were studied by a hydroponic experiment. The results showed that the three microplastics had inhibitory effects on seed germination when the concentration was less than or equal to 500 mg/L, and the inhibition rate ranged from 10.1% to 23.6%. Interestingly, the inhibition effect was alleviated under 1000 mg/L microplastic treatment. Generally, PE was more toxic to seedling growth than PS and PP. Additionally, it was confirmed that microplastics could cause oxidative stress in plants, and PP was relatively less toxic to antioxidant enzymes than PS and PE. These results can provide a theoretical basis and data support for further investigation on the toxicity of microplastics to tomatoes, and contribute to understanding the type specificity of microplastics' toxic effects on plants.


Assuntos
Solanum lycopersicum , Poluentes Químicos da Água , Ecossistema , Microplásticos/toxicidade , Plásticos , Polietileno , Polipropilenos/toxicidade , Poliestirenos/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
5.
J Nanosci Nanotechnol ; 19(1): 176-180, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30327019

RESUMO

Plasmonic subtractive color filters through a nanostructured ultrathin Ag film have attracted intensive attention due to their good durability, high color tunability and high transmission. However, Ag film suffers from discontinuity when the thickness is below 15 nm, which limits the further increasement of transmission efficiency. Herein a bimetal ultrathin (~10 nm) subtractive color filter with one dimensional nanogratings was demonstrated and fabricated. By adding an embedded Al layer to suppress the formation of Ag islands, a smooth, continuous and reliable bimetal film was obtained. At the same time, the blue shift of transmission minimum was beneficial to overcome difficulty in nanostructure fabrication. This method also provided a new approach to tune the color by simply varying the thickness of Al layer. A broad palette of colors, including cyan, magenta and yellow, was attained in bimetal color filter with high transmission beyond 80%.

6.
Chemistry ; 24(41): 10460-10467, 2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-29761568

RESUMO

The lithium-ion capacitor (LIC) has been regarded as a promising device that combines the merits of lithium-ion batteries and supercapacitors, and that meets the requirements for both high energy and high power density. The development of advanced electrode materials is the key requirement. Herein, we report the bottom-up synthesis of activated carbon nanofiber (a-PANF) with a hierarchical porous structure and a high degree of graphitization. Electrospinning has been employed to prepare an interconnected fiber network with macropores, and ferric acetylacetonate has been introduced as both a mesopore-creating agent and a graphitic catalyst to increase the degree of graphitization. Furthermore, chemical activation enlarges the specific surface area by producing abundant micropores. Half-cell evaluation of the as-prepared a-PANF gave a discharge capacity of 80 mA h g-1 at 0.1 A g-1 within 2-4.5 V and no capacity fading after 1000 cycles at 2 A g-1 , which represents a significant improvement compared to conventional activated carbon (AC). Furthermore, an as-assembled LIC with a-PANF cathode and Fe3 O4 anode showed a superior energy density of 124.6 W h kg-1 at a specific power of 93.8 W kg-1 , which remained at 103.7 W h kg-1 at 4687.5 W kg-1 . This indicates promising application potential of a-PANF as an electrode material for efficient energy storage systems.

7.
Sci Total Environ ; 951: 175592, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39154997

RESUMO

N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD), a widely used antioxidant in rubber products, and its corresponding ozone photolysis product N-(1,3-Dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPD-Q), have raised public concerns due to their environmental toxicity. However, there is an existing knowledge gap on the toxicity of 6PPD and 6PPD-Q to aquatic plants. A model aquatic plant, Chlorella vulgaris (C. vulgaris), was subjected to 6PPD and 6PPD-Q at concentrations of 50, 100, 200, and 400 µg/L to investigate their effects on plant growth, photosynthetic, antioxidant system, and metabolic behavior. The results showed that 6PPD-Q enhanced the photosynthetic efficiency of C. vulgaris, promoting growth of C. vulgaris at low concentrations (50, 100, and 200 µg/L) while inhibiting growth at high concentration (400 µg/L). 6PPD-Q induced more oxidative stress than 6PPD, disrupting cell permeability and mitochondrial membrane potential stability. C. vulgaris responded to contaminant-induced oxidative stress by altering antioxidant enzyme activities and active substance levels. Metabolomics further identified fatty acids as the most significantly altered metabolites following exposure to both contaminants. In conclusion, this study compares the toxicity of 6PPD and 6PPD-Q to C. vulgaris, with 6PPD-Q demonstrating higher toxicity. This study provides valuable insight into the risk assessment of tire wear particles (TWPs) derived chemicals in aquatic habitats and plants.


Assuntos
Chlorella vulgaris , Poluentes Químicos da Água , Chlorella vulgaris/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Fotossíntese/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Antioxidantes/metabolismo
8.
J Agric Food Chem ; 72(30): 16674-16686, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39021203

RESUMO

The potential impacts of biodegradable and nonbiodegradable microplastics (MPs) on rhizosphere microbial nitrogen (N) transformation processes remain ambiguous. Here, we systematically investigated how biodegradable (polybutylene succinate, PBS) MPs and nonbiodegradable (polyethylene, PE) MPs affect microbial N processes by determining rhizosphere soil indicators of typical Glycine max (soybean)-soil (i.e., red and brown soils) systems. Our results show that MPs altered soil pH and dissolved organic carbon in MP/soil type-dependent manners. Notably, soybean growth displayed greater sensitivity to 1% (w/w) PBS MP exposure in red soil than that in brown soil since 1% PBS acidified the red soil and impeded nutrient uptake by plants. In the rhizosphere, 1% PBS negatively impacted microbial community composition and diversity, weakened microbial N processes (mainly denitrification and ammonification), and disrupted rhizosphere metabolism. Overall, it is suggested that biodegradable MPs, compared to nonbiodegradable MPs, can more significantly influence the ecological function of the plant-soil system.


Assuntos
Plásticos Biodegradáveis , Biodegradação Ambiental , Glycine max , Microplásticos , Microbiologia do Solo , Solo , Plásticos Biodegradáveis/química , Plásticos Biodegradáveis/metabolismo , Concentração de Íons de Hidrogênio , Microplásticos/química , Microplásticos/metabolismo , Solo/química , Glycine max/química , Glycine max/crescimento & desenvolvimento , Glycine max/metabolismo , Glycine max/microbiologia , Nitrogênio/metabolismo , Rizosfera , Fenômenos Químicos , Microbiota
9.
J Hazard Mater ; 472: 134578, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38743971

RESUMO

Microplastics (MPs) are widespread in agricultural soil, potentially threatening soil environmental quality and plant growth. However, toxicological research on MPs has mainly been limited to individual components (such as plants, microbes, and animals), without considering their interactions. Here, we examined earthworm-mediated effects on tomato growth and the rhizosphere micro-environment under MPs contamination. Earthworms (Eisenia fetida) mitigated the growth-inhibiting effect of MPs on tomato plant. Particularly, when exposed to environmentally relevant concentrations (ERC, 0.02% w/w) of MPs, the addition of earthworms significantly (p < 0.05) increased shoot and root dry weight by 12-13% and 13-14%, respectively. MPs significantly reduced (p < 0.05) soil ammonium (NH4+-N) (0.55-0.69 mg/kg), nitrate nitrogen (NO3--N) (7.02-8.65 mg/kg) contents, and N cycle related enzyme activities (33.47-42.39 µg/h/g) by 37.7-50.9%, 22.6-37.2%, and 34.2-48.0%, respectively, while earthworms significantly enhanced (p < 0.05) inorganic N mineralization and bioavailability. Furthermore, earthworms increased bacterial network complexity, thereby enhancing the robustness of the bacterial system to resist soil MPs stress. Meanwhile, partial least squares modelling showed that earthworms significantly influenced (p < 0.01) soil nutrients, which in turn significantly affected (p < 0.01) plant growth. Therefore, the comprehensive consideration of soil ecological composition is important for assessing MPs ecological risk.


Assuntos
Microplásticos , Oligoquetos , Rizosfera , Poluentes do Solo , Solanum lycopersicum , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/crescimento & desenvolvimento , Oligoquetos/efeitos dos fármacos , Animais , Poluentes do Solo/toxicidade , Microplásticos/toxicidade , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Nitrogênio/metabolismo , Microbiologia do Solo
10.
J Hazard Mater ; 465: 133417, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38183945

RESUMO

The widespread presence of soil microplastics (MPs) has become a global environmental problem. MPs of different properties (i.e., types, sizes, and concentrations) are present in the environment, while studies about the impact of MPs having different properties are limited. Thus, this study investigated the effects of three common polymers (polystyrene, polyethylene, and polypropylene) with two concentrations (0.01% and 0.1% w/w) on growth and stress response of lettuce (Lactuca sativa L.), soil enzymes, and rhizosphere microbial community. Lettuce growth was inhibited under MPs treatments. Moreover, the antioxidant system, metabolism composition, and phyllosphere microbiome of lettuce leaves was also perturbed. MPs reduced phytase activity and significantly increased dehydrogenase activity. The diversity and structure of rhizosphere microbial community were disturbed by MPs and more sensitive to polystyrene microplastics (PSMPs) and polypropylene microplastics (PPMPs). In general, the results by partial least squares pathway models (PLS-PMs) showed that the presence of MPs influenced the soil-rhizosphere-plant system, which may have essential implications for assessing the environmental risk of MPs.


Assuntos
Microbiota , Microplásticos , Poliestirenos , Plásticos , Polietileno/toxicidade , Polipropilenos , Solo , Rizosfera
11.
Sci Total Environ ; 951: 175736, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39182783

RESUMO

N-(1,3-dimethylbutyl)-N '-phenyl-p-phenylenediamine (6PPD) and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPD-Q) are ubiquitous in the environment and can cause toxicity to aquatic animals. However, research on the toxicological effects of 6PPD and 6PPD-Q on aquatic plants remains limited. The present study investigated the physiological, biochemical, and metabolic responses of the floating aquatic plant Eichhornia crassipes (E. crassipes) to environmentally relevant concentrations (0.1, 1, and 10 µg·L-1) of 6PPD and 6PPD-Q. We found that 6PPD and 6PPD-Q elicited minimal effects on plant growth, but 6PPD induced a concentration-dependent decrease in the content of photosynthetic pigments. Low doses (0.1 µg·L-1 and 1 µg·L-1) of 6PPD-Q significantly elevated Reactive Oxygen Species (ROS) content in E. crassipes roots, indicating oxidative damage. Furthermore, 6PPD-Q induced a more pronounced osmotic stress compared to 6PPD. Metabolic analyses revealed that carbohydrates were significantly altered under 6PPD and 6PPD-Q treatments. The findings of this study enhance the understanding of the environmental risks posed by 6PPD and 6PPD-Q to plants and reveal the potential mechanisms of phytotoxicity.


Assuntos
Eichhornia , Estresse Oxidativo , Poluentes Químicos da Água , Eichhornia/metabolismo , Poluentes Químicos da Água/toxicidade , Fenilenodiaminas/toxicidade , Espécies Reativas de Oxigênio/metabolismo
12.
Regen Biomater ; 11: rbae059, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38911700

RESUMO

Currently, the successful healing of critical-sized calvarial bone defects remains a considerable challenge. The immune response plays a key role in regulating bone regeneration after material grafting. Previous studies mainly focused on the relationship between macrophages and bone marrow mesenchymal stem cells (BMSCs), while dural cells were recently found to play a vital role in the calvarial bone healing. In this study, a series of 3D elastomers with different proportions of polycaprolactone (PCL) and poly(glycerol sebacate) (PGS) were fabricated, which were further supplemented with polydopamine (PDA) coating. The physicochemical properties of the PCL/PGS and PCL/PGS/PDA grafts were measured, and then they were implanted as filling materials for 8 mm calvarial bone defects. The results showed that a matched and effective PDA interface formed on a well-proportioned elastomer, which effectively modulated the polarization of M2 macrophages and promoted the recruitment of dural cells to achieve full-thickness bone repair through both intramembranous and endochondral ossification. Single-cell RNA sequencing analysis revealed the predominance of dural cells during bone healing and their close relationship with macrophages. The findings illustrated that the crosstalk between dural cells and macrophages determined the vertical full-thickness bone repair for the first time, which may be the new target for designing bone grafts for calvarial bone healing.

13.
Sci Total Environ ; 859(Pt 1): 160025, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36356752

RESUMO

Much attention has been paid to the prevalence of microplastics (MPs) in terrestrial systems. MPs have been shown to affect the physio-biochemical properties of plants. Different MPs may have distinctive behaviors and diverse effects on plant growth. In the present study, the effects of polystyrene (PS), polyethylene (PE), and polypropylene (PP) MPs on physio-biochemical properties, root exudates, and metabolomics of tomato (Lycopersicon esculentum L.) under hydroponic conditions were investigated. Our results show that MPs exposure has adverse effects on tomato growth. MPs exposure had a significant type-dependent effect (p < 0.001) on photosynthetic gas parameters, chlorophyll content, and antioxidant enzyme activities. After exposure to MPs, the content of low molecular weight organic acids in tomato root exudates was significantly increased, which was considered as a strategy to alleviate the toxicity of MPs. In addition, MPs treatment significantly changed the metabolites of tomato root and leaf. Metabolic pathway analysis showed that MPs treatment had a great effect on amino acid metabolism. We also found that plants exposed to PS and PP MPs produced more significant metabolic reprogramming than those exposed to PE MPs. This study provides important implications for the mechanism studies on the toxic effect of various MPs on crops and their future risk assessment.


Assuntos
Solanum lycopersicum , Poluentes Químicos da Água , Microplásticos/toxicidade , Plásticos/toxicidade , Poliestirenos/toxicidade , Polietileno , Antioxidantes
14.
Plant Physiol Biochem ; 194: 513-523, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36516538

RESUMO

The contamination of nanoplastics (NPs) and heavy metals (HM) in water bodies has caused widespread concern, while their effects on submerged plants are poorly reported. Polystyrene nanoplastics (PSNPs) and arsenic (As) were used to assess their toxicity on Myriophyllum verticillatum L. via the orthogonal experiments. PSNPs significantly reduced the accumulation of As (17.24%-66.67%) in plant. Single As and high As-PSNPs treatments significantly inhibited plant growth, with a maximum reduction of 70.09% in the growth rate. The mineral nutrient content was significantly affected by PSNPs and As treatments. The antioxidant system was significantly inhibited, which was more pronounced in the roots. Similar findings were observed for soluble protein and soluble sugar. Some organic acids and amino acids showed down-regulation at high concentrations of As, leading to a decrease in the content of the mineral element and down-regulation of antioxidant enzyme synthesis. Furthermore, PSNPs could alleviate As toxicity under 0.1 mg/L As treatment but exacerbate As toxicity at 1 mg/L As dose. This study has important implications for the study of submerged plants exposed to co-contamination of microplastics and heavy metals, as well as the possible ecological risk assessment in freshwater.


Assuntos
Arsênio , Metais Pesados , Poliestirenos/toxicidade , Arsênio/toxicidade , Microplásticos , Plásticos , Antioxidantes , Metais Pesados/toxicidade
15.
Sci Total Environ ; 905: 167129, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730039

RESUMO

As pollution has attracted attention due to its wide distribution. An environmental concern that may be overlooked is that NPs additives are easily released into the environment due to their physical combination with NPs. However, the knowledge gaps still exist about the interfacial reactions of NPs and the additives (e.g. flame retardants) and the joint ecological effect. In the present study, fourier transform infrared (FTIR) spectrometer coupled with 2D correlation spectroscopy (2D-COS) analysis revealed the interfacial reactions between polystyrene nanoplastics (PSNPs) and Dechlorane Plus (DP). Results showed that carbon­oxygen bonds and carbon­chlorine bonds were the important binding sites during adhesion and DP could reduce the colloidal stability. Single and joint ecological effects of PSNPs and DP on the microalgae Chlorella vulgaris were further deliberated. Reduced photosynthetic efficiency (reduced Fv/Fm by 0.03 %), higher growth inhibition (16.15 %) and oxidative damage (increased ROS by 152 %) were observed in algae under co-exposure. Notably, DP could significantly increase the attachment of PSNPs to the surface of the algae. Metabolomics further revealed that co-exposure significantly down-regulated amino acid metabolism and tricarboxylic acid cycle (TCA) cycle, and up-regulated fatty acid metabolism. The present study provides new insights into the risk assessment of NPs in aquatic environment by investigating the interfacial reaction mechanism and combined ecotoxicity of NPs and additives.


Assuntos
Chlorella vulgaris , Poliestirenos , Poliestirenos/metabolismo , Microplásticos/toxicidade , Chlorella vulgaris/metabolismo , Carbono
16.
Sci Total Environ ; 874: 162496, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-36863597

RESUMO

Despite the increasing research on the fate of nanoplastics (NPs, <100 nm) in freshwater systems, little is known about the joint toxic effects of metal(loid)s and NPs modified with different functional groups on microalgae. Here, we explored the joint toxic effects of two types of polystyrene NPs [one modified with a sulfonic acid group (PSNPs-SO3H), and one without this functional group (PSNPs)] and arsenic (As) on the microalgae Microcystis aeruginosa. The results highlighted that PSNPs-SO3H showed a smaller hydrodynamic diameter and greater potential to adsorb positively charged ions than PSNPs, contributing to the more severe growth inhibition, while both of them produced oxidative stress. Metabolomics further revealed that the fatty acid metabolism of the microalgae was significantly up-regulated under both NPs exposure, while PSNPs-SO3H down-regulated the tricarboxylic acid cycle (TCA cycle) of the microalgae. As uptake by algae was significantly reduced by 82.58 % and 59.65 % in the presence of 100 mg/L PSNPs and PSNPs-SO3H, respectively. The independent action model showed that the joint toxicity of both NPs with As was assessed as antagonistic. In addition, PSNPs and PSNPs-SO3H had dissimilar effects on the composition of the microalgae extracellular polymeric substances (EPS), resulting in different uptake and adsorption of As, thereby affecting the physiology and biochemistry of algae. Overall, our findings propose that the specific properties of NPs should be considered in future environmental risk assessments.


Assuntos
Arsenitos , Microcystis , Poliestirenos/metabolismo , Microplásticos/toxicidade , Microcystis/metabolismo
17.
Sci Total Environ ; 872: 162291, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36801330

RESUMO

Nanoplastics (NPs) and heavy metals are widely distributed in aquatic ecosystem, posing a potential threat to ecosystem function. Submerged macrophytes play an important role in water purification and maintaining ecological functions. However, the coupled effects of NPs and cadmium (Cd) on submerged macrophytes physiology and the mechanisms involved are still unclear. Here, the potential effects of single and co-Cd/PSNPs exposure on Ceratophyllum demersum L. (C. demersum) were explored. Our results showed that NPs aggravated the inhibition of Cd on plant growth ate (a decrease of 35.54 %), reduced chlorophyll synthesis (a decrease of 15.84 %), and disrupted the antioxidant enzyme system (a decrease of 25.07 % on SOD activity) of C. demersum. Massive PSNPs adhered to the surface of C. demersum when exposed to co-Cd/PSNPs while they did not adhere when exposed to single-NPs. The metabolic analysis further demonstrated that co-exposure down-regulated plant cuticle synthesis and that Cd exacerbated the physical damage and shadowing effects of NPs. In addition, co-exposure upregulated pentose phosphate metabolism, leading to the accumulation of starch grains. Furthermore, PSNPs reduced Cd enrichment capacity of C. demersum. Our results unraveled distinct regulatory networks for submerged macrophytes exposed to single and composite of Cd and PSNPs, providing a new theoretical basis for assessing the risks of heavy metals and NPs in the freshwater environment.


Assuntos
Cádmio , Metais Pesados , Cádmio/toxicidade , Cádmio/metabolismo , Microplásticos , Poliestirenos , Ecossistema , Metais Pesados/toxicidade , Metais Pesados/metabolismo , Plantas/metabolismo
18.
J Hazard Mater ; 443(Pt B): 130372, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36444066

RESUMO

Considering the stability and economy of immobilized enzymes, this study prepared co-modified biochar immobilized laccase product named Fe3O4@NaBC@GA@LC via orthogonal experimental design and explored its possibility of remediating polycyclic aromatic hydrocarbons (PAHs) contaminated soil in steel plants. Compared with the free laccase treatment, the relative activity of Fe3O4@NaBC@GA@LC remained 60 % after 50 days of incubation at room temperature. The relative activity of Fe3O4@NaBC@GA@LC could still retain nearly 80 % after five reuses. In the process of simulating the PAHs-contaminated site treatment experiment in Hangzhou Iron and steel plant, immobilized laccase exhibited efficient adsorption and degradation performances and even the removal rate of 5-ring PAHs reached more than 90 % in 40 days, resulting in improving urease activity and dehydrogenase in the soil and promoted the growth of a PAH degrading bacteria (Massilia). Our results further explained the efficient degradation effects of Fe3O4@NaBC@GA@LC on PAHs, which make it a promising candidate for PAHs-contaminated soil remediation.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Lacase , Bactérias , Solo , Aço
19.
Plant Physiol Biochem ; 194: 589-599, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36529009

RESUMO

Microplastics (MPs) have been a global emerging contaminant and have aroused wide public concern. Currently, it is still unknown the phytotoxicity effect of MPs on amaranth (Amaranthus mangostanus L.). This study investigated the early responses of amaranth by exposing its seeds to suspensions of polystyrene (PS), polyethylene (PE), and polypropylene (PP) MPs. We observed the effects of MPs on seed germination and growth of amaranth, especially on the oxidative damage in amaranth roots. Impacts of MPs on the germination and growth of amaranth varied with the type, concentration, and particle size of MPs. PE MPs and PP MPs inhibited the shoot extension of amaranth, while the root length under PP MPs treatment was generally shorter than that under PS MPs and PE MPs. The accumulation of H2O2 in amaranth roots increased with the rising of MPs concentration. Compared with the control, a little number of dead cells were found in the roots of amaranth under high MPs treatment. It is noteworthy that only under 100 mg/L PP treatment, the amaranthus seedlings root cells were disorganized, due to the reactive oxygen species (ROS) damage in the roots. These findings provide essential information to assess the phytotoxicity of MPs in agricultural products, and provide insights into the underlying mechanisms of the observed phytotoxicity.


Assuntos
Amaranthus , Plântula , Germinação , Microplásticos/farmacologia , Plásticos , Peróxido de Hidrogênio/farmacologia
20.
Sci Rep ; 13(1): 9000, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37268700

RESUMO

The objective of this study was to detective the accuracy of model superimposition and automatic analysis for upper and lower dentition width in Invisalign Progress Assessment during the process of clear aligners. 19 cases were included in this study. Pre-treatment dental cast (T0) and post-treatment dental cast after staged treatment (T1) were available for three-dimensional model superimposition. Subsequently, movements of maxillary teeth in the horizontal plane (cross-section) after staged treatment and width of upper and lower dentition were measured by three-dimensional model superimposition in the real world and Invisalign Progress Assessment separately. Consequently, the data collected from these two methods were compared. In Invisalign Progress Assessment, movements of maxillary teeth in the horizontal plane after staged treatment was 2.31 (1.59,3.22) [median (upper quartile, lower quartile)] millimeter (mm), while in three-dimensional model superimposition, the result was 1.79 (1.21,3.03) mm. The difference between the two groups is significant (P < 0.05). Intercanine width upper, intermolar width upper, intercanine width lower, and intermolar width lower were 36.55 ± 2.76 mm, 56.98 ± 2.62 mm, 28.16 ± 1.85 mm, 53.21 ± 2.72 mm separately in Invisalign Progress Assessment and were 36.48 ± 2.78 mm, 56.89 ± 2.58 mm, 28.05 ± 1.85 mm, 53.16 ± 2.64 mm separately in three-dimensional model analysis, which was no significant difference among these groups (P > 0.05). The data from Invisalign Progress Assessment was not in parallel with what was achieved from model superimposition with palate as a reference completely. The accuracy of model superimposition in Invisalign Progress Assessment needs further investigation, whereas the accuracy of model analysis in Invisalign Progress Assessment was accurate. Thereby, results from Invisalign Progress Assessment should be interpreted with caution by the orthodontist in the clinic.


Assuntos
Aparelhos Ortodônticos Removíveis , Técnicas de Movimentação Dentária , Estudos Retrospectivos , Palato
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