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1.
Water Res ; 261: 121985, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38968734

RESUMEN

This study introduces a novel approach to transport modelling by integrating experimentally derived causal priors into neural networks. We illustrate this paradigm using a case study of metformin, a ubiquitous pharmaceutical emerging pollutant, and its transport behaviour in sandy media. Specifically, data from metformin's sandy column transport experiment was used to estimate unobservable parameters through a physics-based model Hydrus-1D, followed by a data augmentation to produce a more comprehensive dataset. A causal graph incorporating key variables was constructed, aiding in identifying impactful variables and estimating their causal dynamics or "causal prior." The causal priors extracted from the augmented dataset included underexplored system parameters such as the type-1 sorption fraction F, first-order reaction rate coefficient α, and transport system scale. Their moderate impact on the transport process has been quantitatively evaluated (normalized causal effect 0.0423, -0.1447 and -0.0351, respectively) with adequate confounders considered for the first time. The prior was later embedded into multilayer neural networks via two methods: causal weight initialization and causal prior regularization. Based on the results from AutoML hyperparameter tuning experiments, using two embedding methods simultaneously emerged as a more advantageous practice since our proposed causal weight initialization technique can enhance model stability, particularly when used in conjunction with causal prior regularization. amongst those experiments utilizing both techniques, the R-squared values peaked at 0.881. This study demonstrates a balanced approach between expert knowledge and data-driven methods, providing enhanced interpretability in black-box models such as neural networks for environmental modelling.


Asunto(s)
Metformina , Redes Neurales de la Computación , Porosidad , Contaminantes Químicos del Agua/química
2.
Environ Sci Technol ; 58(32): 14496-14505, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39047231

RESUMEN

Although massive studies have investigated the spatiotemporally occurring marine plastisphere, a new microbial ecosystem colonizing the surfaces of plastics, the resulting biofragmentation process and impacts of plastics on biogeochemical cycles remain largely unknown. Here, we leverage synchrotron-based Fourier transform infrared spectromicroscopy (FTIR mapping) and metagenomic sequencing to explore independent marine microcosms amended with petroleum-based polyethylene (PE) and biobased polyhydroxybutyrate (PHB) plastic films. FTIR mapping results demonstrate unequal fragmentation scenarios by which the PE plastic rarely releases oxidized fragments while PHB disintegrates quickly, gradually forming fragments composed of extracellular polymeric substances resembling plastic films. Metagenomic analysis shows the critical role of hydrocarbonoclastic lineages in the biodegradation of the two plastics by the fatty acid degradation pathway, where the PE plastics host different microbial trajectories between the plastisphere (dominated by Alcanivorax) and surrounding seawater. In contrast, the PHB addition demonstrates decreased microbial richness and diversity, consistent community composition (dominated by Phaeobacter and Marinobacter), and apparently stimulated sulfur cycle and denitrification pathways in both the plastisphere and surrounding seawater. Our study gives scientific evidence on the marine biotic processes distinguishing petroleum- and biobased plastics, highlighting marine PHB input exerting straightforward impacts on the water phase and deserving critical management practices.


Asunto(s)
Plásticos , Polietileno , Biodegradación Ambiental , Agua de Mar/microbiología , Agua de Mar/química , Hidroxibutiratos/metabolismo , Poliésteres/química
3.
Int Urol Nephrol ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886300

RESUMEN

PURPOSE: To evaluate the association between vitamin D receptor (VDRs) and calcium-sensitive receptor (CaSR) gene polymorphisms and calcium-containing kidney stones (CCKS) in Dai populations. METHODS: A total of 160 CCKS patients and 87 healthy controls were included in this study. CCKS was confirmed using urological computed tomography (CT), plain abdominal radiograph, or surgical lithotomy. Stone samples obtained during surgery were analyzed using infrared spectroscopy. Venous blood and 24-h urine samples were collected and analyzed using Sanger sequencing and high-performance liquid chromatography, respectively. Genetic variants in the VDR gene (rs7975232, rs2228570, rs731236, and rs1544410) and CaSR gene (rs7652589, rs1801725, and rs1042636) were identified through sequence analysis. RESULTS: Analysis of genotype and allele frequencies revealed that the rs7975232 polymorphism in the VDR gene and the rs7652589 allele in the CaSR gene were significantly associated with CCKS. Furthermore, patients carrying the AC and AA genotypes of rs7975232 showed a higher incidence of hypocitraturia compared to those with other genotypes (p < 0.05). The AA and GG genotypes of rs1042636 and the AA genotype of rs7652589 were significantly associated with hypercalciuria (p < 0.05). CONCLUSION: CCKS in this study population may be closely related to hypocitraturia caused by the VDR locus rs7975232 polymorphism and hypercalciuria caused by the CaSR locus rs1042636 and rs7652589 polymorphism.

4.
Chemosphere ; 358: 142171, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38714247

RESUMEN

Marine oil spills directly cause polycyclic aromatic hydrocarbons (PAHs) pollution and affect marine organisms due to their toxic property. Chemical and bio-based dispersants composed of surfactants and solvents are considered effective oil spill-treating agents. Dispersants enhance oil biodegradation in the marine environment by rapidly increasing their solubility in the water column. However, the effect of dispersants, especially surfactants, on PAHs degradation by enzymes produced by microorganisms has not been studied at the molecular level. The role of the cytochrome P450 (CYP) enzyme in converting contaminants into reactive metabolites during the biodegradation process has been evidenced, but the activity in the presence of surfactants is still ambiguous. Thus, this study focused on the evaluation of the impact of chemical and bio-surfactants (i.e., Tween 80 (TWE) and Surfactin (SUC)) on the biodegradation of naphthalene (NAP), chrysene (CHR), and pyrene (PYR), the representative components of PAHs, with CYP enzyme from microalgae Parachlorella kessleri using molecular docking and molecular dynamics (MD) simulation. The molecular docking analysis revealed that PAHs bound to residues at the CYP active site through hydrophobic interactions for biodegradation. The MD simulation showed that the surfactant addition changed the enzyme conformation in the CYP-PAH complexes to provide more interactions between the enzyme and PAHs. This led to an increase in the enzyme's capability to degrade PAHs. Binding free energy (ΔG||Bind) calculations confirmed that surfactant treatment could enhance PAHs degradation by the enzyme. The SUC gave a better result on NAP and PYR biodegradation based on ΔG||Bind, while TWE facilitated the biodegradation of CHR. The research outputs could greatly facilitate evaluating the behaviors of oil spill-treating agents and oil spill response operations in the marine environment.


Asunto(s)
Biodegradación Ambiental , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Contaminación por Petróleo , Hidrocarburos Policíclicos Aromáticos , Tensoactivos , Contaminantes Químicos del Agua , Hidrocarburos Policíclicos Aromáticos/metabolismo , Hidrocarburos Policíclicos Aromáticos/química , Tensoactivos/química , Tensoactivos/metabolismo , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/química , Sistema Enzimático del Citocromo P-450/metabolismo , Chlorophyta/metabolismo
5.
Dalton Trans ; 53(19): 8443-8453, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38686440

RESUMEN

In contrast to the energy-consuming Haber-Bosch process, ammonia synthesis by electrocatalysis under ambient conditions is an efficient and environmentally friendly method. In this work, through first principles calculations, the potential of four dual-atom FeTM (TM = Fe, Mo, Co, and V) anchored graphyne (FeTM@GY) as efficient nitrogen reduction reaction (NRR) catalysts is systematically investigated. Among them, FeMo@GY is the most promising, with excellent NRR catalytic activity, high ability to suppress the competing hydrogen evolution reaction (HER), and good stability. Moreover, NRR prefers the maximum pathway with the calculated onset potentials of -0.27 V for FeMo@GY. This work not only suggests that FeMo@GY holds great promise as an efficient, low-cost, and stable dual-atom catalyst for NRR but also further provides a guiding idea for the design of efficient NRR catalysts.

6.
J Hazard Mater ; 469: 133832, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38428295

RESUMEN

Effective marine oil spill responses are vital to reduce environmental, societal, and economic damage. This study developed a Multi-Criteria Emergency Response System (MC-ERS) to comprehensively evaluate response efficiency, operational costs, and environmental losses. The proposed system integrates dynamic multiphase simulation of oil weathering and oil cleanup processes and further provides effective planning for multi-stage resource allocation through system optimization. The developed weight-sum model improved the performance of response operations by reducing the complexity of multi-criteria decision-making. Particle Swarm Optimization (PSO) was chosen as the foundational optimization algorithm due to its efficiency in rapid convergence and suitability for complex problems. From extensive comparisons of PSO variants across benchmark functions and inertia strategies, the C-PSO algorithm was developed, demonstrating enhanced optimization performance for MC-ERS. The developed modelling system performance was demonstrated and evaluated through a representative case study. The optimization plan coordinated resource allocation from onshore warehouses to harbors and spill sites, balancing oil recovery efficiency, costs, and ecological losses. Optimized results indicate an oil recovery of up to 76.50% in five days. Additionally, the system cuts costs by 3.45% and environmental losses by 15.75%. The findings enhance the efficiency of marine oil spill emergency response and provide support for such incidents.

7.
J Hazard Mater ; 469: 133980, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38492391

RESUMEN

Hydroxyl radicals (·OH) produced in subsurface sediments play an important role in biogeochemical cycles. One of the major sources of·OH in sediments is associated with reduced compounds (e.g., iron and organic matter) oxygenation. Moreover, the properties of iron forms and dissolved organic matter (DOM) components varied significantly across redox-fluctuation zones of estuaries. However, the influence of these variations on mechanisms of·OH production in estuaries remains unexplored. Herein, sediments from riparian zones, wetlands, and rice fields in the Yellow River Estuary were collected to systematically explore the diverse mechanisms of·OH generation. Rhythmic continuous·OH production (82-730 µmol/kg) occurred throughout the estuary, demonstrating notable spatial heterogeneity. The amorphous iron form and humic-like DOM components were the key contributors to·OH accumulation in estuary wetlands and freshwater restoration wetlands, respectively. The crystalline iron form and protein-like DOM components influenced the capabilities of iron reduction and continuous·OH production. Moreover, the orthogonal partial least squares models outperformed various multivariate models in screening crucial factors and predicting the spatiotemporal production of·OH. This study provides novel insights into varied mechanisms of·OH generation within distinct redox-fluctuation zones in estuaries and further elucidates elemental behavior and contaminant fate in estuarine environments. ENVIRONMENTAL IMPLICATION: Given that estuaries serve as sinks for anthropogenic pollutants, various organic pollutants (e.g., emerging contaminants such as antibiotics) have been widely detected in estuarine environments. The production of·OH in sediments has been proven to affect the fate of contaminants. Therefore, the varied mechanisms of·OH in estuarine environments, dominated by diverse iron forms and DOM components, were explored in this study. MLR and OPLS models exhibited good performance in screening crucial factors and predicting·OH production. Our work highlights that in estuarine subsurface environments, the presence of·OH potentially leads to a natural degradation of pollutants.

8.
Sci Total Environ ; 923: 171451, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38438027

RESUMEN

This research presents the successful development and optimization of a spiropyran-assisted cellulose aerogel (CNF-SP) aerogel with UV-induced switchable wettability, and the evaluation of its performance as an effective oil sorbent for oil spill cleanup. The aerogel initially exhibited strong hydrophobicity (124°) and showed UV-induced switchable wettability due to the photo-response structure of spiropyran. Upon UV irradiation, the hydrophobicity of the aerogel could be switched to hydrophilicity (31°), while visible light irradiation could restore its hydrophobicity. The three-dimensional (3D) porous structure of the CNF-SP aerogel combined with the hydrophobic properties of spiropyranol led to its great oil adsorption performance (27-30 g/g of oil adsorption ratio). The central composite design (CCD) was applied to optimize the aerogel and investigate the effects of raw material ratio (i.e., carboxymethyl cellulose, carboxyethyl spiropyran, polyvinyl alcohol, and nano zinc oxide) on the oil sorption performance of the aerogel. The optimized CNF-SP aerogel demonstrated a high oil sorption efficiency, particularly in acid and cold environments. Moreover, the switchable function indicated that the aerogel exhibited reusability and renewability, with the added benefit of UV-induced oil recovery.

9.
Int Wound J ; 21(1): e14649, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38272796

RESUMEN

Facial soft tissue injuries, often resulting in scarring, pose a challenge in reconstructive and aesthetic surgery due to the need for functional and aesthetic restoration. This study evaluates the efficacy of recombinant human growth factors (rhGFs) in scar remodelling for such injuries. A retrospective evaluation was conducted from January 2020 to January 2023, involving 100 patients with facial soft tissue injuries. Participants were divided equally into a control group, receiving standard cosmetic surgical repair, and an observation group, treated with rhGFs supplemented cosmetic surgery. The study assessed scar characteristics (pigmentation, pliability, vascularity, height), hospital stay duration, tissue healing time, complication rates and patient satisfaction. The observation group demonstrated significant improvements in all scar characteristics, with notably better pigmentation, pliability, vascularity and height compared with the control group. The rhGF treatment also resulted in reduced hospital stay duration and faster tissue healing. Notably, the total complication rate was significantly lower in the observation group (10%) compared with the control group (34%). Additionally, patient satisfaction levels were higher in the observation group, with 98% combined satisfaction compared with 76% in the control group. The application of rhGFs in treating facial soft tissue injuries significantly enhances scar remodelling, expedites healing, reduces complications and improves patient satisfaction. These findings establish rhGFs as a valuable tool in the management of facial soft tissue injuries, highlighting their potential in improving both functional and aesthetic outcomes.


Asunto(s)
Traumatismos Faciales , Procedimientos de Cirugía Plástica , Traumatismos de los Tejidos Blandos , Humanos , Cicatriz/tratamiento farmacológico , Cicatriz/cirugía , Estudios Retrospectivos , Cicatrización de Heridas , Traumatismos de los Tejidos Blandos/tratamiento farmacológico , Traumatismos de los Tejidos Blandos/cirugía , Traumatismos Faciales/tratamiento farmacológico , Traumatismos Faciales/cirugía , Resultado del Tratamiento
10.
Sci Total Environ ; 917: 170527, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38286285

RESUMEN

The global ocean has been receiving massive amounts of plastic wastes. Marine biodegradation, influenced by global climate, naturally breaks down these wastes. In this study, we systematically compared the biodegradation performance of petroleum- and bio-based plastic films, i.e., low-density polyethylene (LDPE), polylactic acid (PLA), and polyhydroxyalkanoates (PHAs) under three ambient temperatures (4, 15, and 22 °C). We deployed the our previously isolated cold-tolerant plastic-degrading Alcanivorax to simulate the accelerated marine biodegradation process and evaluated the alteration of bacterial growth, plastic films, and released degradation products. Notably, we found that marine biodegradation of PHA films enriched more bacterial amounts, induced more conspicuous morphological damage, and released more microplastics (MPs) and dissolved organic carbon (DOC) under all temperatures compared to LDPE and PLA. Particularly, MPs were released from film edges and cracks with a mean size of 2.8 µm under all temperatures. In addition, the degradation products released by biodegradation of PHA under 22 °C induced the highest acute toxicity to Vibrio fischeri. Our results highlighted that: (1) marine biodegradation of plastics would release millions of MPs per cm2 exposed surface area even in cold environments within 60 days; (2) different marine biodegradation scenarios of these plastics may raise disparate impacts and mitigation-related studies.


Asunto(s)
Alcanivoraceae , Polihidroxialcanoatos , Plásticos/metabolismo , Alcanivoraceae/metabolismo , Polietileno/metabolismo , Temperatura , Biodegradación Ambiental , Bacterias/metabolismo , Microplásticos/metabolismo , Polihidroxialcanoatos/metabolismo
11.
J Hazard Mater ; 465: 133187, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38104519

RESUMEN

A quantitative understanding of spilled oil transport in a nearshore environment is challenging due to the complex physicochemical processes in aqueous conditions. The physicochemical processes involved in oil sinking mainly include oil dispersion, sediment settling, and oil-sediment interaction. For the first time, this work attempts to address the sinking mechanism in petroleum contaminant transport using structural causal models based on observed data. The effects of nearshore salinity distribution from the estuary to the ocean on those three processes are examined. The causal inference reveals sediment settling is the crucial process for oil sinking. Salinity indirectly affects oil sinking by promoting sediment settling rather than directly affecting oil-sediment interaction. The increase of salinity from 0‰ to 35‰ provides a natural enhancement for sediment settling. Notably, unbiased causal effect estimates demonstrate the strongest positive causal effect on the settling efficiency of sediments is posed by increasing oil dispersion effectiveness, with a normalized value of 1.023. The highest strength of the causal relationship between oil dispersion and sediment settling highlights the importance of the dispersing characteristics of spilled oil to sediment-facilitated oil transport. The employed logic, a data-driven method, will shed light on adopting advanced causal inference tools to unravel the complicated contaminants' transport.

12.
J Hazard Mater ; 465: 133220, 2024 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-38101020

RESUMEN

N-(1,3-Dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD) is one of the most widely used antioxidant agents in tire additives. Its ozonation by-product 6PPD-quinone has recently been recognized as inducing acute mortality in aquatic organisms such as coho salmon. In this study, we aimed to develop an in-silico method to design environmentally friendly 6PPD derivatives and evaluate the joint toxicity of 6PPD with other commonly used tire additives on coho salmon through full factorial design-molecular docking and molecular dynamic simulation. The toxicity mentioned in this study is represented by the binding energy of chemical(s) binding to the coho salmon growth hormone. The recommended formula for tire additives with relatively low toxicity was then proposed. To further reduce the toxicity of 6PPD, 129 6PPD derivatives were designed based on the N-H bond dissociation reaction, and three of these derivatives showed improved antioxidant activity and 6PPD-106 was finally screened as the optimum alternative with lower toxicity to coho salmon. Besides, the mechanism of free radical oxidation (i.e., antioxidation and ozonation metabolic pathway) for 6PPD-106 was also analyzed and found that after ozonation, the toxicity of 6PPD-106's by-products is much lower than that of 6PPD's by-products. This study provided a molecular modelling-based examination of 6PPD, which comprehensively advanced the understanding of 6PPD's environmental behaviors and provided more environmentally friendly 6PPD alternatives with desired functional property and lower ecological risks.


Asunto(s)
Antioxidantes , Ozono , Simulación del Acoplamiento Molecular , Oxidación-Reducción , Benzoquinonas , Radicales Libres , Fenilendiaminas
13.
Angew Chem Int Ed Engl ; 62(52): e202314565, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-37943183

RESUMEN

The active-site density, intrinsic activity, and durability of Pd-based materials for oxygen reduction reaction (ORR) are critical to their application in industrial energy devices. This work constructs a series of carbon-based rare-earth (RE) oxides (Gd2 O3 , Sm2 O3 , Eu2 O3 , and CeO2 ) by using RE metal-organic frameworks to tune the ORR performance of the Pd sites through the Pd-REx Oy interface interaction. Taking Pd-Gd2 O3 /C as a representative, it is identified that the strong coupling between Pd and Gd2 O3 induces the formation of the Pd-O-Gd bridge, which triggers charge redistribution of Pd and Gd2 O3 . The screened Pd-Gd2 O3 /C exhibits impressive ORR performance with high onset potential (0.986 VRHE ), half-wave potential (0.877 VRHE ), and excellent stability. Similar ORR results are also found for Pd-Sm2 O3 /C, Pd-Eu2 O3 /C, and Pd-CeO2 /C catalysts. Theoretical analyses reveal that the coupling between Pd and Gd2 O3 promotes electron transfer through the Pd-O-Gd bridge, which induces the antibonding-orbital occupancy of Pd-*OH for the optimization of *OH adsorption in the rate-determining step of ORR. The pH-dependent microkinetic modeling shows that Pd-Gd2 O3 is close to the theoretical optimal activity for ORR, outperforming Pt under the same conditions. By its ascendancy in ORR, the Pd-Gd2 O3 /C exhibits superior performance in Zn-air battery as an air cathode, implying its excellent practicability.

14.
Sci Total Environ ; 905: 167279, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-37741386

RESUMEN

The transfer of antibiotic resistance genes (ARGs) from soils to plants is poorly understood, especially the role of host bacteria in soils and its impact on seed-derived bacteria. Wheat (Triticum aestivum L.) was thus used to fill the gap by conducting pot experiments, with target ARGs and bacterial community analyzed. Results showed that the relative abundances of target ARGs gradually decreased during transfer of ARGs from the rhizosphere soil to root and shoot. Host bacteria in the rhizosphere soil were the primary source of ARGs in wheat. The 38, 21, and 19 potential host bacterial genera of target ARGs and intI1 in the rhizosphere soil, root, and shoot were identified, respectively, and they mainly belonged to phylum Proteobacteria. The abundance of ARGs carried by pathogenic Corynebacterium was reduced in sequence. During transfer of ARGs from the rhizosphere soil to root and shoot, some seed-derived bacteria and pathogenic Acinetobacter obtained ARGs through horizontal gene transfer and became potential host bacteria. Furthermore, total organic carbon, available nitrogen of the rhizosphere soil, water use efficiency, vapor pressure deficit, and superoxide dismutase of plants were identified as the key factors affecting potential host bacteria transfer in soils to wheat. This work provides important insights into transfer of ARGs and deepens our understanding of potential health risks of ARGs from soils to plants.


Asunto(s)
Antibacterianos , Triticum , Antibacterianos/farmacología , Suelo , Genes Bacterianos , Microbiología del Suelo , Bacterias/genética , Farmacorresistencia Microbiana/genética , Semillas , Estiércol/microbiología
15.
Mar Pollut Bull ; 194(Pt A): 115371, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37591051

RESUMEN

Although the marine oil spill pollution issue does not bring us to flock in droves as the new emerging oceanic techniques like wave energy converters, remote operated vehicle (ROV), blue ammonia and green hydrogen, the huge pollution risks of the marine oil spills caused by man-made intentional discharge, old equipment, accidental leakage, war and other aspects should arouse our sufficient attention and concern. As the primary countermeasure of emergency response to a marine oil spill, rapid & efficient oil containment is crucial to limit the pollution scope and the subsequent recovery and treatment. Here, we summarized the existing investigations on oil-spill containment with a marked emphasis on the applications of bubble curtains and their working mechanisms. The critical research progress and trends about the remediation techniques and the application of bubble curtains in marine environments were briefly introduced. The article thoroughly analyzed the basic working mechanism of the bubble curtains in oil spill containment, the technical difficulties of the existing methods, the potential application prospects of coupling with the traditional oil containment booms and the critical scientific problems to be studied in the future. Regarding the issues involving insufficient oil retention performance and inconvenient deployment of the existing traditional oil boom under complex and variable sea conditions, the performance and structural optimization of bubble curtain enhanced oil containment boom will get the top priority in developing the next-generation oil containment techniques.


Asunto(s)
Contaminación por Petróleo , Amoníaco , Contaminación Ambiental , Hidrodinámica , Contaminación por Petróleo/prevención & control , Contaminación del Agua
16.
ACS Appl Mater Interfaces ; 15(33): 39332-39341, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37556456

RESUMEN

Photoinduced charge separation and surface reactions are essential for ensuring high quantum efficiency of the photochemical and photophysical processes. BiVO4-based heterojunctions are promising materials for high-performance photocatalysts; however, their photocatalytic performance is significantly lower than the theoretical limit due to the sluggish water oxidation dynamics and rapid recombination of charge carriers on the catalyst surface. To address these issues, oxygen vacancies (OVs) are introduced to a rationally designed BiVO4-based heterojunction using built-in potential and gradient OVs to promote the separation of carriers and increase the photocatalytic activity. The heterojunctions with OVs exhibit a 2-fold increase in the photocatalytic activity for phenol degradation compared with that of pristine BiVO4. Additionally, density functional theory is applied to elucidate the synergistic mechanism of light absorption and charge separation in BiOCl/BiVO4 p-n heterojunction photocatalysts containing vacancies. The obtained results demonstrate a synergistic effect of vacancies and the built-in potential, providing a pathway for defect engineering in photocatalytic processes.

17.
Sci Total Environ ; 894: 164960, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37348724

RESUMEN

This study investigated the interactions between rhizosphere and endosphere bacteria during phytoextraction and how the interactions affect arsenic (As) extraction and carbon (C) fixation of plants. Pot experiments, high-throughput sequencing, metabonomics, and network analysis were integrated. Results showed that positive correlations dominated the interconnections within modules (>95 %), among modules (100 %), and among keystone taxa (>72 %) in the bacterial networks of plant rhizosphere, root endosphere, and shoot endosphere. This confirmed that cooperative interactions occurred between bacteria in the rhizosphere and endosphere during phytoextraction. Modules and keystone taxa positively correlating with plant As extraction and C fixation were identified, indicating that modules and keystone taxa promoted plant As extraction and C fixation simultaneously. This is mainly because modules and keystone taxa in plant rhizosphere, root endosphere, and shoot endosphere carried arsenate reduction and C fixation genes. Meanwhile, they up-regulated the significant metabolites related to plant As tolerance. Additionally, shoot C fixation increased peroxidase activity and biomass thereby facilitating plant As extraction was confirmed. This study revealed the mechanisms of plant-associated bacterial interactions contributing to plant As extraction and C fixation. More importantly, this study provided a new angle of view that phytoextraction can be applied to achieve multiple environmental goals, such as simultaneous soil remediation and C neutrality.


Asunto(s)
Arsénico , Microbiota , Arsénico/metabolismo , Raíces de Plantas/microbiología , Microbiología del Suelo , Bacterias/metabolismo , Rizosfera , Ciclo del Carbono
18.
Neural Regen Res ; 18(10): 2260-2267, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37056146

RESUMEN

The regenerative capacity of the central nervous system is very limited and few effective treatments are currently available for spinal cord injury. It is therefore a priority to develop new drugs that can promote structural and functional recovery after spinal cord injury. Previous studies have shown that peptides can promote substantial repair and regeneration of injured tissue. While amphibians have a pronounced ability to regenerate the spinal cord, few studies have investigated the effect of amphibian spinal cord-derived peptides on spinal cord injury. Here we report for the first time the successful identification and isolation of a new polypeptide, VD11 (amino acid sequence: VDELWPPWLPC), from the spinal cord of an endemic Chinese amphibian (Odorrana schmackeri). In vitro experiments showed that VD11 promoted the secretion of nerve growth factor and brain-derived neurotrophic factor in BV2 cells stimulated with lipopolysaccharide, as well as the proliferation and synaptic elongation of PC12 cells subjected to hypoxia. In vivo experiments showed that intravertebral injection of VD11 markedly promoted recovery of motor function in rats with spinal cord injury, alleviated pathological damage, and promoted axonal regeneration. Furthermore, RNA sequencing and western blotting showed that VD11 may affect spinal cord injury through activation of the AMPK and AKT signaling pathways. In summary, we discovered a novel amphibian-derived peptide that promotes structural and functional recovery after spinal cord injury.

19.
Chemosphere ; 329: 138678, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37059196

RESUMEN

This is the first study investigating the effects of freeze-thaw (FT) and microplastics (MPs) on the distribution of antibiotic resistance genes (ARGs) in soil aggregates (i.e., soil basic constituent and functional unit) via microcosm experiments. The results showed that FT significantly increased the total relative abundance of target ARGs in different aggregates due to the increase in intI1 and ARG host bacteria. However, polyethylene MPs (PE-MPs) hindered the increase in ARG abundance caused by FT. The host bacteria carrying ARGs and intI1 varied with aggregate size, and the highest number of hosts was observed in micro-aggregates (<0.25 mm). FT and MPs altered host bacteria abundance by affecting aggregate physicochemical properties and bacterial community and enhanced multiple antibiotic resistance via vertical gene transfer. Although the dominant factors affecting ARGs varied with aggregate size, intI1 was a co-dominant factor in various-sized aggregates. Furthermore, other than ARGs, FT, PE-MPs, and their integration promoted the proliferation of human pathogenic bacteria in aggregates. These findings suggested that FT and its integration with MPs significantly affected ARG distribution in soil aggregates. They amplified antibiotic resistance environmental risks, contributing to a profound understanding of soil antibiotic resistance in the boreal region.


Asunto(s)
Antibacterianos , Suelo , Humanos , Antibacterianos/farmacología , Suelo/química , Microplásticos , Plásticos , Genes Bacterianos , Bacterias/genética , Farmacorresistencia Microbiana/genética , Microbiología del Suelo
20.
Nano Lett ; 23(6): 2287-2294, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36898060

RESUMEN

Strong coupling between light and mechanical strain forms the foundation for next-generation optical micro- and nano-electromechanical systems. Such optomechanical responses in two-dimensional materials present novel types of functionalities arising from the weak van der Waals bond between atomic layers. Here, by using structure-sensitive megaelectronvolt ultrafast electron diffraction, we report the experimental observation of optically driven ultrafast in-plane strain in the layered group IV monochalcogenide germanium sulfide (GeS). Surprisingly, the photoinduced structural deformation exhibits strain amplitudes of order 0.1% with a 10 ps fast response time and a significant in-plane anisotropy between zigzag and armchair crystallographic directions. Rather than arising due to heating, experimental and theoretical investigations suggest deformation potentials caused by electronic density redistribution and converse piezoelectric effects generated by photoinduced electric fields are the dominant contributors to the observed dynamic anisotropic strains. Our observations define new avenues for ultrafast optomechanical control and strain engineering within functional devices.

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