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The aging of Pb added to soils has not been studied by the isotopic technology because of difficulties in determination of isotopically exchangeable Pb in soil, so that a set of 10 typical agricultural soils in China and a one-year aging experiment with the addition of water-soluble Pb to the soils were carried out. A modified stable isotope dilution technique to determine isotopically exchangeable Pb in soil was developed where 0.2 mM EDTA (ethylenediaminetetraacetic acid) as the extractant. When water-soluble Pb was added to soil, the isotopically exchangeable Pb (Eadd%, the percentage of isotopically exchangeable Pb to total Pb added to soil) initially decreased rapidly and gradually slowly. A semi-mechanistic aging model of Pb added to soils, including precipitation/nucleation (Y1), micropore diffusion (Y2), and organic matter encapsulation processes (Y3) was developed with the root mean square error 8.3% where Y1, Y2, and Y3 accounted for 0.02~26.9%, 1.4~21.8% and 3.8~11.3%, respectively, when the pH 4.0~8.0 and organic matter 2.0~6.0%. Soil pH was a vital factor affecting the aging rate. When the pH increased by 1 unit, the Eadd value decreased by approximately 9%. The model could be used to scale ecotoxicological data of Pb in soil generated in different aging times.
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The land application of sewage sludge from wastewater treatment plants has been recognized as a major source of microplastic contamination in soil. Nevertheless, the fate and behavior of microplastics in soil remain uncertain, particularly their distribution and transport, which are poorly understood. This study does a bibliometric analysis and visualization of relevant research publications using the CiteSpace software. It explores the limited research available on the topic, highlighting the potential for it to emerge as a research hotspot in the future. Chinese researchers and institutions are paying great attention to this field and are promoting close academic cooperation among international organizations. Current research hot topics mainly involve microplastic pollution caused by the land application of sewage sludge, as well as the detection, environmental fate, and removal of microplastics in soil. The presence of microplastics in sludge, typically ranging from tens of thousands to hundreds of thousands of particles (p)/kg, inevitably leads to their introduction into soil upon land application. In China, the estimated annual accumulation of microplastics in the soil due to sludge use is approximately 1.7 × 1013 p. In European countries, the accumulation ranges from 8.6 to 71 × 1013 p. Sludge application has significantly elevated soil microplastic concentrations, with higher application rates and frequencies resulting in up to several-fold increases. The primary forms of microplastics found in soils treated with sludge are fragments and fibers, primarily in white color. These microplastics consist primarily of components such as polyamide, polyethylene, and polypropylene. The vertical transport behavior of microplastics is influenced by factors such as tillage, wind, rainfall, bioturbation, microplastic characteristics (e.g., fraction, particle size, and shape), and soil physicochemical properties (e.g., organic matter, porosity, electrical conductivity, and pH). Research indicates that microplastics can penetrate up to 90 cm into the soil profile and persist for decades. Microplastics in sewage sludge-amended soils pose potential long-term threats to soil ecosystems and even human health. Future research should focus on expanding the theoretical understanding of microplastic behavior in these soils, enabling the development of comprehensive risk assessments and informed decision-making for sludge management practices. PRACTITIONER POINTS: Microplastics in sewage sludge range from tens to hundreds of thousands per kilogram. Sludge land application contributes significantly to soil microplastic pollution. The main forms of microplastics in sludge-amended soils are fragments and fibers. Microplastics are mainly composed of polyamide, polyethylene, and polypropylene. Microplastics can penetrate up to 90 cm into the soil profile and persist for decades.
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Microplásticos , Aguas del Alcantarillado , Contaminantes del Suelo , Suelo , Aguas del Alcantarillado/química , Microplásticos/análisis , Contaminantes del Suelo/análisis , Suelo/química , Bibliometría , Monitoreo del AmbienteRESUMEN
When Cr(VI) and Cr(III) coexist, the reasonable assessment of the combined toxicity of chromium in soil and its ecological risk is still not well resolved. In the present study, exogenous mixed concentration combinations were set up to determine the interaction and combined toxicity of Cr(VI) and Cr(III), which were quantified as measured total and resin extractable forms for dose-response experiments with barley root elongation. The concept of toxicity equivalence "α" (the ratio of toxicity intensity coefficient between Cr(VI) and Cr(III), which can be expressed as the relative toxic strength of Cr(VI) to Cr(III)) was proposed for the toxicity assessment of mixed-valence chromium in soil. The results showed that the dose-response relationship was determined more precisely by the extended independent action model (e-IA) than traditional models (e.g., concentration addition model), and the mutual antagonism for resin extractable form (Resin-Cr) was stronger than the measured total form (T-Cr). The values of toxicity equivalence (α) between coexisting Cr(VI) and Cr(III) as Resin-Cr and T-Cr were 0.74 and 160, respectively, which indicated Resin-Cr(III) had relatively stronger toxicity than Resin-Cr(VI), while T-Cr(III) was much less than T-Cr(VI). The α values between Cr(VI) and Cr(III) decreased with their more active forms (decreased to about 0.5% of the original), even as total concentration and activity in solutions, making a dialectical view of the toxicity of both in different forms necessary. Finally, the log-logistic models were developed, enabling mixed-valence Cr toxicity to be assessed from a unilateral perspective using the Cr(III) equivalence concentration (Cr(III)-eq). This work provided innovative ideas for ecological threshold studies for mixed-valence metals in soils.
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Intrinsic resistance to macrolides in Gram-negative bacteria is primarily attributed to the low permeability of the outer membrane, though the underlying genetic and molecular mechanisms remain to be fully elucidated. Here, we used transposon directed insertion-site sequencing (TraDIS) to identify chromosomal non-essential genes involved in Escherichia coli intrinsic resistance to a macrolide antibiotic, tilmicosin. We constructed two highly saturated transposon mutant libraries of >290,000 and >390,000 unique Tn5 insertions in a clinical enterotoxigenic strain (ETEC5621) and in a laboratory strain (K-12 MG1655), respectively. TraDIS analysis identified genes required for growth of ETEC5621 and MG1655 under 1/8 MIC (n = 15 and 16, respectively) and 1/4 MIC (n = 38 and 32, respectively) of tilmicosin. For both strains, 23 genes related to lipopolysaccharide biosynthesis, outer membrane assembly, the Tol-Pal system, efflux pump, and peptidoglycan metabolism were enriched in the presence of the antibiotic. Individual deletion of genes (n = 10) in the wild-type strains led to a 64- to 2-fold reduction in MICs of tilmicosin, erythromycin, and azithromycin, validating the results of the TraDIS analysis. Notably, deletion of surA or waaG, which impairs the outer membrane, led to the most significant decreases in MICs of all three macrolides in ETEC5621. Our findings contribute to a genome-wide understanding of intrinsic macrolide resistance in E. coli, shedding new light on the potential role of the peptidoglycan layer. They also provide an in vitro proof of concept that E. coli can be sensitized to macrolides by targeting proteins maintaining the outer membrane such as SurA and WaaG.
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Antibacterianos , Elementos Transponibles de ADN , Farmacorresistencia Bacteriana , Escherichia coli , Macrólidos , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Macrólidos/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Elementos Transponibles de ADN/genética , Farmacorresistencia Bacteriana/genética , Proteínas de Escherichia coli/genética , Tilosina/farmacología , Tilosina/análogos & derivadosRESUMEN
In recent years, emerging evidence has revealed a strong association between dysregulations of long non-coding RNAs (lncRNAs) and sophisticated human diseases. Biological experiments are adequate to identify such associations, but they are costly and time-consuming. Therefore, developing high-quality computational methods is a challenging and urgent task in the field of bioinformatics. This paper proposes a new lncRNA-disease association inference approach NFMCLDA (Network Fusion and Matrix Completion lncRNA-Disease Association), which can effectively integrate multi-source association data. In this approach, miRNA information is used as the transition path, and an unbalanced random walk method on three-layer heterogeneous network is adopted in the preprocessing. Therefore, more effective information between networks can be mined and the sparsity problem of the association matrix can be solved. Finally, the matrix completion method accurately predicts associations. The results show that NFMCLDA can provide more accurate lncRNA-disease associations than state-of-the-art methods. The areas under the receiver operating characteristic curves are 0.9648 and 0.9713, respectively, through the cross-validation of 5-fold and 10-fold. Data from published case studies on four diseases - lung cancer, osteosarcoma, cervical cancer, and colon cancer - have confirmed the reliable predictive potential of NFMCLDA model.
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MicroARNs , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Biología Computacional/métodos , Neoplasias/genética , Predisposición Genética a la Enfermedad/genética , FemeninoRESUMEN
Alkaline media widely exist in natural and engineered systems such as semiarid/arid areas, radioactive waste sites, and mine tailings. In these settings, the commonly occurring iron (oxyhydr)oxides differed in their ability to influence the fate of nutrients and contaminants. Due to the substantially increased atmospheric carbon dioxide (CO2) concentration, carbonate stands to increase in these media. However, how increasing carbonate affects the transformation of poorly crystalline iron (oxyhydr)oxides (e.g., two-line ferrihydrite) under alkaline conditions still remains unclear. Here, kinetics of ferrihydrite transformation were evaluated at pH â¼10 as a function of [carbonate] = 0-286 mM using synchrotron-based X-ray and vibrational spectroscopic techniques. The results showed that carbonate slowed down ferrihydrite transformation slightly and suppressed goethite formation, but promoted hematite formation regardless of its concentration. At low carbonate concentration (11.42 mM), the effect of carbonate on product formation was obvious due to the weak inner-sphere complex; however, at high carbonate concentration (80-286 mM), the effect was retarded because of the adsorption equilibrium of carbonate as well as the initial carbonate adsorption followed by desorption. Moreover, carbonate modified the morphology of hematite from rhombic to ellipsoidal to honeycomb and goethite from rod-like to needle-like to spindle-like due to the inner-sphere adsorption-desorption of carbonate and adsorption of hydroxyl ions on reactive sites of iron (oxyhydr)oxides in alkaline media. The results suggest that the concurrently increasing carbonate with enhanced atmospheric CO2 could control the transformation and occurrence of iron (oxyhydr)oxides in natural and engineered environments and have important implications for the biogeochemical cycles of iron and carbon.
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Dióxido de Carbono , Compuestos Férricos , Compuestos de Hierro , Compuestos Férricos/química , Minerales/química , Hierro/química , Óxidos , Carbonatos , Adsorción , Oxidación-ReducciónRESUMEN
The intensification of pharmaceutical use globally has led to an increase in the number of water bodies contaminated by drugs, and an effective strategy must be developed to address this issue. In this work, several biochars produced from Miscanthus straw pellets (MSP550, MSP700) and wheat straw pellets (WSP550, WSP700) at 550 and 700°C, respectively, were selected as adsorbents for removing various pharmaceuticals, such as pemetrexed (PEME), sulfaclozine (SCL), and terbutaline (TBL), from the aqueous phase. The biochar characterizations (physicochemical properties, textural properties, morphological structures, and zeta potentials) and adsorptive conditions (contact times, temperatures, and pH effect) were investigated. The infrared and Raman spectra of biochars before and after pharmaceutical adsorption, as well as quantum chemical computations, were carried out to explore the adsorption mechanisms. The results showed that the general adsorption abilities of biochars for pharmaceuticals were in the order of WSP700 > MSP700 > MSP550 > WSP550. Both the higher drug concentration and higher temperature improved biochar adsorption. By decreasing the pH, the adsorption amounts increased for PEME and SCL. However, TBL exhibited the best adsorption at pH 7, whereas a weakening of affinity occurred at lower or higher pH values. Electrostatic interactions and hydrogen bonding were the main adsorptive mechanisms between all biochars and pharmaceuticals. π-π interactions played a role in the adsorption process of low-temperature-prepared biochars (MSP550 and WSP550). This work can provide new insights into the control of pharmaceuticals from water with low-cost adsorbents. PRACTITIONER POINTS: Use of biochars for pharmaceuticals removal from aqueous phase. Characterization of biochars : physical and chemical properties, textural and surface properties. Simulation calculation for characterization of pharmaceuticals. Kinetic studies of pharmaceuticals adsorption on biochars. DRIFTS and Raman analysis for the understanding of adsorption process.
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Carbón Orgánico , Agua , Cinética , Carbón Orgánico/química , Preparaciones Farmacéuticas , AdsorciónRESUMEN
We propose and investigate a class of aperiodic grating structure which can achieve perfect Talbot effect under certain conditions. The aperiodic grating structure is obtained by the superposition of two or more sine terms. In the case of two sine terms, the Talbot effect can be realized when the period ratio of two terms is arbitrary. While in the case of more than two sine terms, the period ratios of each term must meet certain extra conditions. The theory has been further verified by numerical simulations. It expands the field of Talbot effect and is of potential significance for subsequent research applications such as optical imaging and measurement.
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High-efficiency electrocatalytic water splitting requires high intrinsic activity of catalysts and even more importantly favorable mass transfer. However, gas bubbles adhering to the surface of catalysts limit the re-expose of catalytic active sites to the electrolyte and reduce the catalytic activities. The efficient desorption of bubbles can be facilitated by a hierarchical multiscale structure of the electrode surface. Herein, we report an opened periodic three-dimensional electrode composed of iron (Fe)-cobalt (Co)-nickel (Ni) (oxy)hydroxide nanorods (NRs) grown in situ on a high aspect ratio nickel microcolumn array (NCA) for electrocatalytic water splitting. Compared with the flat nickel plate, the NCA not only increases the surface area for catalyst loading but also improves the wettability of the electrolyte on the electrode surface, exhibiting superhydrophilicity/superaerophobicity (the electrolyte and the bubble contact angles were about â¼0 and 163°, respectively), which accelerates the bubble evolution and desorption process. The X-ray photoelectron spectroscopy indicates that the synergy of Fe-Co-Ni could enhance the ratio of Co3+/Co2+ and Ni3+/Ni2+ and promote the electrocatalytic activity. Benefiting from the microstructure design and synergistic effects, the Co4Fe0.5Ni0.5OOH-NR@NCA electrode achieves a superior OER performance with an overpotential of 199 mV at 10 mA·cm-2.
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Paddy fields located around estuaries suffer from seawater intrusion, and how and to what extent salinity levels influence Cd accumulation in rice grains is still unclear. Pot experiments were carried out by cultivating rice under alternating flooding and drainage conditions with different salinity levels (0.2, 0.6 and 1.8). The Cd availability was greatly enhanced at 1.8 salinity due to the competition for binding sites by cations and the formation of Cd complexation with anions, which also contributed to Cd uptake by rice roots. The soil Cd fractions were investigated and found that the Cd availability significantly decreased during flooding stage, while it rapidly increased after soil drainage. During drainage stage, Cd availability was greatly enhanced at 1.8 salinity mainly attributed to the formation of CdCln2-n. The kinetic model was established to quantitatively evaluate Cd transformation, and it found that the release of Cd from organic matter and Fe-Mn oxides was greatly enhanced at 1.8 salinity. The results of pot experiments showed that there was a significant increase in Cd content in rice roots and grains in the treatment of 1.8 salinity, because the increasing salinity induced an increase in Cd availability and upregulation of key genes regulating Cd uptake in rice roots. Our findings elucidated the key mechanisms by which high salinity enhanced Cd accumulation in rice grains, and more attention should be given to the food safety of rice cultivated around estuaries.
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Oryza , Contaminantes del Suelo , Cadmio/metabolismo , Oryza/metabolismo , Contaminantes del Suelo/metabolismo , Suelo/química , Óxidos/metabolismoRESUMEN
The slow oxygen evolution reaction (OER) limits water splitting, and external fields can help improve it. However, the effect of a single external field on the OER is limited and unsatisfactory. Furthermore, the mechanism by which external fields improve the OER is unclear, particularly in the presence of multiple fields. Herein, a strategy is proposed for enhancing the OER activity of a catalyst using the combined effect of an optical-magnetic field, and the mechanism of catalytic activity enhancement is studied. Under the optical-magnetic field, Co3 O4 reduces the resistance by increasing the catalyst temperature. Meanwhile, CoFe2 O4 further reduces the resistance via the negative magnetoresistance effect, thus decreasing the resistance from 16 to 7.0 Ω. Additionally, CoFe2 O4 acts as a spin polarizer, and electron polarization results in a parallel arrangement of oxygen atoms, which increases the kinetics of the OER under the magnetic field. Benefiting from the optical and magnetic response design, Co3 O4 /CoFe2 O4 @Ni foam requires an overpotential of 172.4 mV to reach a current density of 10 mA cm-2 under an optical-magnetic field, which is significantly higher than those of recently reported state-of-the-art transition-metal-based catalysts.
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It is significant to establish an accurate model to predict cadmium (Cd) criteria for safe wheat production. More importantly, for better evaluation of the risk of Cd pollution in high natural background areas, the soil extractable Cd criteria are needed. In the present study, the soil total Cd criteria were derived using the method of cultivars sensitivity distribution integrated with soil aging and bioavailability as affected by soil properties. Firstly, the dataset that meet the requirements was established. Dataset from thirty-five wheat cultivars planted in different soils published in literature of five bibliographic databases were screened using designated search strings. Then, the empirical soil-plant transfer model was used to normalize the bioaccumulation data. Afterwards, the soil Cd concentration for protecting 95 % (HC5) of the species was calculated from species sensitivity distribution curves, and the derived soil criteria were obtained from HC5 prediction models that based on pH. The process of derivation for soil EDTA-extractable Cd criteria was the same way as the soil total Cd criteria. Soil total Cd criteria ranged from 0.25 to 0.60 mg/kg and soil EDTA-extractable Cd criteria ranged from 0.12 to 0.30 mg/kg. Both the criteria of soil total Cd and soil EDTA-extractable Cd were further validated to be reliable using data from field experiments. The results suggested that the criteria of soil total Cd and soil EDTA-extractable Cd in the study can ensure the safety of Cd in wheat grains and thereby enable local agricultural practitioners to develop appropriate management for croplands.
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Contaminantes del Suelo , Suelo , Suelo/química , Cadmio/análisis , Triticum/química , Ácido Edético , Contaminantes del Suelo/análisisRESUMEN
There has been growing concern among the public over the environmental impacts of the copper (Cu) mining and mineral processing industries. As an effective tool enabling interactions of all energy and material flows with the environment, Life Cycle Assessment (LCA) is used in many countries to identify environmental hotspots associated with operations, based on which improvements can be made. However, robust LCA research in this sector is lacking in China. This study aimed to fill this critical gap by investigating two typical Cu mining and mineral processing operations using different mining technologies, based on globally harmonized LCA methodologies. The results of the overall environmental impacts were obtained using a sensitivity analysis. Electricity (38%-74%), diesel (8%-24%) and explosives (4%-22%) were identified as the three main controlling factors. At the same time, the mineral processing stage was found to be the major production stage (60%-79%), followed by the mining stage (17%-39%) and the wastewater treatment (1%-13%). Global Warming Potential (GWP) was prioritized as the most important environmental issue (59%) across the selected impact categories. In addition, it was initially found that underground mining technology has better environmental performance than open-pit technology. Finally, the potential for improvement was estimated and discussed for the three identified controlling factors. Using GWP as an example, using green electricity can effectively reduce CO2 emissions by 47%-67%, whereas replacing diesel and explosives with cleaner fuels and explosives may contribute to lower CO2 emissions by 6% and 9%, respectively.
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Cobre , Sustancias Explosivas , Dióxido de Carbono , Ambiente , Minería , MineralesRESUMEN
Due to its high mobility and bioavailability, hexavalent chromium [Cr(VI)] in agricultural soil can be taken up by crops and pose threat to human being. In this study, two soils (Jiangxi red soil and Shandong fluvo-aquic soil) spiked with Cr(VI) and 8 common vegetable varieties were used to conduct the pot experiment. The bioconcentration factor (BCF) values based on the tetraacetic acid extractable Cr (EDTA-Cr) in soils were used to construct the species sensitivity distribution (SSD) curve. Afterwards, the soil Cr threshold was derived based on the critical BCF value and the permissible limit of Cr for vegetables. The results showed that when spiked with 5.6 mg kg-1 of Cr(â ¥), the soil EDTA-Cr concentrations were significantly increased compared with the control except Jiangxi red soil planted with carrot and radish, while the Cr concentrations in the edible parts of vegetables in both soils were below the permissible limit (0.5 mg kg-1 FW). However, there are dramatic differences in the accumulation of Cr by different varieties of vegetables. Apparent discrepancy was observed between the two soils for the bioconcentration of Cr by carrot. Among the leafy vegetables, lettuce and oilseed rape are the most and the least sensitive to Cr pollution, respectively. The safety threshold values of EDTA-Cr were 0.70 mg kg-1 for Shandong fluvo-aquic soil and 0.85 mg kg-1 for Jiangxi red soil, respectively. This study provides information on the safety production of vegetable products in Cr(â ¥) polluted soils and is helpful to the revision of soil quality standards of Cr.
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Contaminantes del Suelo , Verduras , Humanos , Suelo , Ácido Edético , Contaminantes del Suelo/análisisRESUMEN
Microplastics (MPs) are regarded as potential persistent organic pollutants owing to their small size and low degradability. However, the effect of MP pollution on greenhouse gas (GHG) emissions from farmland soil is yet unclear. Therefore, a series of microcosm experiments were set up using polyvinyl chloride (PVC), polypropylene (PP), polyethylene (PE), polystyrene (PS), and polyester (PET) at concentrations of 0.25 %, 2 %, and 7 % (w/w). Each treatment had three replicates. This experiment was carried out to verify the effect of MP pollution on greenhouse gas (GHG) emissions from farmland soil. The results showed that the addition of MPs significantly promoted the emissions of the three main GHGs, including nitrous oxide (N2O), carbon dioxide (CO2), and methane (CH4). Especially, PE may cause most GHG emissions which would contribute to climate warming when its pollution concentration increased. In addition, different doses and types of MPs could affect microbial community structure. These findings of this present study may provide a scientific and practical reference for the prevention and control of MPs pollution and risk assessment of global climate change caused by MPs.
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Gases de Efecto Invernadero , Microbiota , Gases de Efecto Invernadero/análisis , Suelo/química , Microplásticos , Plásticos , Granjas , Dióxido de Carbono/análisis , Óxido Nitroso/análisis , Metano/análisis , PolietilenoRESUMEN
The promotion of magnetic field on catalytic performance has attracted extensive attention. However, little research has been reported on the performance of the oxygen evolution reaction (OER) for the modulating intrinsic magnetism of the catalyst under a magnetic field. Herein, we adjusted the intrinsic magnetism of the CoxNi1-xFe2O4-nanosheet by adjusting the ratio of Co and Ni, and researched the relationship between the OER activity and the intrinsic magnetism. The results indicate that the CoFe2O4-nanosheet has the most OER activity increases in the magnetic field due to the optimal intrinsic magnetism. The required overpotential of CoFe2O4-nanosheet@NF to reach a current density of 10 mA cm-2 was reduced by 21 mV under about 100 mT magnetic field compared with no magnetic field, and the degree of improvement of OER activity of different magnetic catalysts in the same magnetic field is positively correlated with the intrinsic magnetism of the catalyst. Therefore, magnetic field assistance provides a new, effective, and general strategy to improve the activity of electrodes for water splitting.
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Hindered gas bubble release and limited electron conducting process represent the major bottlenecks for large-scale electrochemical water splitting. Both the desorption of bubbles and continuous electron transport are achievable on the surfaces of biomimetic catalytic materials by designing multiscale structural hierarchy. Inspired by the tubular structures of the deep-sea sponges, an exceptionally active and binder-free porous nickel tube arrays (PNTA) decorated with NiFe-Zn2+ -pore nanosheets (NiFe-PZn ) are fabricated. The PNTA facilitate removal of bubbles and electron transfer in the oxygen evolution reaction by reproducing trunks of the sponges, and simultaneously, the NiFe-PZn increase the number of catalytic active sites by simulating the sponge epidermis. With improved external mass transfer and interior electron transfer, the hierarchical NiFe-PZn @PNTA electrode exhibits superior oxygen evolution reaction performance with an overpotential of 172 mV at 10 mA cm-2 (with a Tafel slope of 50 mV dec-1 ). Furthermore, this electrocatalytic system recorded excellent reaction stability over 360 h with a constant current density of 100 mA cm-2 at the potential of 1.52 V (versus RHE). This work provides a new strategy of designing hierarchical electrocatalysts for highly efficient water splitting.
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ABSTRACT Introduction Psychological monitoring and psychological intervention of basketball players has been a focus of attention in sports training. In basketball, players consume much physical energy and also much mental energy. Psychological tension and emotional changes cause basketball players to restrict their technical abilities. Objective Analyze the relationship between sport-induced mental fatigue and pre-game emotions in basketball players. Methods This paper selects 40 basketball players as research volunteers. A survey questionnaire and mathematical statistics were used to analyze the relationship between basketball players' mental fatigue, training level, and pre-game emotions. This paper analyzes the relationship between psychological quality and training level of basketball players. Results There were significant correlations between various dimensions of sport-induced mental fatigue and basketball players' pregame emotions. Basketball players' pre-game self-confidence is mainly affected by training game competence and excessive energy consumption. Conclusion The psychological quality of basketball players is significantly correlated with the level of training. Athletes should pay attention to psychological quality training in sports competitions. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.
RESUMO Introdução O acompanhamento psicológico e a intervenção psicológica dos jogadores de basquete tem sido foco de atenção no treinamento esportivo. No basquetebol, os jogadores consomem muita energia física e também muita energia mental. A tensão psicológica e as alterações emocionais fazem com que os jogadores de basquetebol restrinjam suas habilidades técnicas. Objetivo Analisar a relação entre a fadiga mental induzida pelo esporte e as emoções pré-jogo nos jogadores de basquete. Métodos Este trabalho seleciona 40 jogadores de basquetebol como voluntários de pesquisa. Utilizou-se um questionário de pesquisa e estatísticas matemáticas para analisar a relação entre a fadiga mental dos jogadores de basquetebol, o nível de treinamento e as emoções pré-jogo. Este trabalho analisa a relação entre a qualidade psicológica e o nível de treinamento dos jogadores de basquetebol. Resultados Houve correlações significativas entre as várias dimensões da fadiga mental induzida pelo esporte e a emoção no pré-jogo dos jogadores de basquete. A autoconfiança dos jogadores de basquetebol antes do jogo é afetada principalmente pela competência dos jogos de treinamento e pelo consumo excessivo de energia. Conclusão A qualidade psicológica dos jogadores de basquetebol está significativamente correlacionada com o nível de treinamento. Os atletas devem prestar atenção ao treinamento de qualidade psicológica nas competições esportivas. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.
RESUMEN Introducción El acompañamiento psicológico y la intervención psicológica de los jugadores de baloncesto han sido objeto de atención en el entrenamiento deportivo. En el baloncesto, los jugadores consumen mucha energía física y también mucha energía mental. La tensión psicológica y los cambios emocionales hacen que los jugadores de baloncesto limiten sus habilidades técnicas. Objetivo Analizar la relación entre la fatiga mental inducida por el deporte y las emociones previas al partido en jugadores de baloncesto. Métodos Este trabajo selecciona a 40 jugadores de baloncesto como voluntarios para la investigación. Para analizar la relación entre la fatiga mental de los jugadores de baloncesto, el nivel de entrenamiento y las emociones previas al partido se utilizó un cuestionario de encuesta y estadísticas matemáticas. Este artículo analiza la relación entre la calidad psicológica y el nivel de entrenamiento de los jugadores de baloncesto. Resultados Hubo correlaciones significativas entre las diversas dimensiones de la fatiga mental inducida por el deporte y las emociones previas al partido de los jugadores de baloncesto. La autoconfianza de los jugadores de baloncesto antes del partido se ve afectada principalmente por la competencia del juego de entrenamiento y el consumo excesivo de energía. Conclusión La calidad psicológica de los jugadores de baloncesto está significativamente correlacionada con el nivel de entrenamiento. Los deportistas deben prestar atención a la calidad psicológica del entrenamiento en las competiciones deportivas. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.
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The harm of microplastics (MPs) to aquatic ecosystems is caused by their stable and non-degradable properties. Additionally, the pollutants such as heavy metals in the water are easy to be adsorbed on their surface with their small particle size and large specific surface area, resulting in environmental pollution. Therefore, the study on the mixture toxicity of MPs and heavy metals has theoretical significance for the risk assessment of aquatic ecosystems. In the present study, 10 nm polystyrene (PS) and cadmium (Cd) were used, and their individual and mixture acute toxicities on grass carp (Ctenopharyngodon idellus) were examined. The results indicated that the mortality of the fish increased with the concentration from 10 mg L-1 to 20 mg L-1, and the existence of PS-MPs elevated the Cd concentrations in the fish and accelerated the death. Whether the Cd and/or the PS-MPs concentrations caused varying degrees of damage to the gills, kidney, liver, and muscles of the grass carp, especially under the highest concentrations (20 mg L-1 Cd + 300 µg L-1 PS-MPs). Moreover, low concentrations of PS-MPs alone (30 µg L-1 PS-MPs) significantly increased the superoxide dismutase (SOD) activity in the kidney and liver, reaching 12.43% and 14.38%, respectively (P < 0.05). The peroxidase (POD) activity was increased only in the kidney, up to 25.95% (P < 0.05). Also, significant reductions in SOD and POD activities were observed in the combination of high concentration of Cd (20 mg L-1) and 300 µg L-1 PS-MPs (P < 0.05). To the best of our knowledge, there are few studies on the impact of combined toxicity of PS-MPs and Cd on grass carp under laboratory conditions. Therefore, these findings may provide a theoretical guarantee for pollution prevention and control in the aquatic ecosystem.
Asunto(s)
Carpas , Contaminantes Ambientales , Metales Pesados , Contaminantes Químicos del Agua , Animales , Antioxidantes/metabolismo , Cadmio/toxicidad , Carpas/metabolismo , Ecosistema , Microplásticos/toxicidad , Estrés Oxidativo , Peroxidasas , Plásticos/toxicidad , Poliestirenos/toxicidad , Superóxido Dismutasa/metabolismo , Agua , Contaminantes Químicos del Agua/toxicidadRESUMEN
Escherichia coli is intrinsically resistant to macrolides due to outer membrane impermeability, but may also acquire macrolide resistance genes by horizontal transfer. We evaluated the prevalence and types of acquired macrolide resistance determinants in pig clinical E. coli, and we assessed the ability of peptidomimetics to potentiate different macrolide subclasses against strains resistant to neomycin, a first-line antibiotic in the treatment of pig-enteric infections. The erythromycin MIC distribution was determined in 324 pig clinical E. coli isolates, and 62 neomycin-resistant isolates were further characterized by genome sequencing and MIC testing of azithromycin, spiramycin, tilmicosin, and tylosin. The impact on potency achieved by combining these macrolides with three selected peptidomimetic compounds was determined by checkerboard assays in six strains representing different genetic lineages and macrolide resistance gene profiles. Erythromycin MICs ranged from 16 to >1,024 µg/mL. Azithromycin showed the highest potency in wild-type strains (1 to 8 µg/mL), followed by erythromycin (16 to 128 µg/mL), tilmicosin (32 to 256 µg/mL), and spiramycin (128 to 256 µg/mL). Isolates with elevated MIC mainly carried erm(B), either alone or in combination with other acquired macrolide resistance genes, including erm(42), mef(C), mph(A), mph(B), and mph(G). All peptidomimetic-macrolide combinations exhibited synergy (fractional inhibitory concentration index [FICI] < 0.5) with a 4- to 32-fold decrease in the MICs of macrolides. Interestingly, the MICs of tilmicosin in wild-type strains were reduced to concentrations (4 to 16 µg/mL) that can be achieved in the pig intestinal tract after oral administration, indicating that peptidomimetics can potentially be employed for repurposing tilmicosin in the management of E. coli enteritis in pigs. IMPORTANCE Acquired macrolide resistance is poorly studied in Escherichia coli because of intrinsic resistance and limited antimicrobial activity in Gram-negative bacteria. This study reveals new information on the prevalence and distribution of macrolide resistance determinants in a comprehensive collection of porcine clinical E. coli from Denmark. Our results contribute to understanding the correlation between genotypic and phenotypic macrolide resistance in E. coli. From a clinical standpoint, our study provides an initial proof of concept that peptidomimetics can resensitize E. coli to macrolide concentrations that may be achieved in the pig intestinal tract after oral administration. The latter result has implications for animal health and potential applications in veterinary antimicrobial drug development in view of the high rates of antimicrobial-resistant E. coli isolated from enteric infections in pigs and the lack of viable alternatives for treating these infections.