High-capacity dilithium hydroquinone cathode material for lithium-ion batteries.

Lithiated organic cathode materials show great promise for practical applications in lithium-ion batteries owing to their Li-reservoir characteristics. However, the reported lithiated organic cathode materials still suffer from strict synthesis conditions and low capacity. Here we report a thermal intermolecular rearrangement method without organic solvents to prepare dilithium hydroquinone (Li2Q), which delivers a high capacity of 323 mAh g-1 with an average discharge voltage of 2.8 V. The reversible conversion between orthorhombic Li2Q and monoclinic benzoquinone during charge/discharge processes is revealed by in situ X-ray diffraction. Theoretical calculations show that the unique Li-O channels in Li2Q are beneficial for Li+ ion diffusion. In situ ultraviolet-visible spectra demonstrate that the dissolution issue of Li2Q electrodes during charge/discharge processes can be handled by separator modification, resulting in enhanced cycling stability. This work sheds light on the synthesis and battery application of high-capacity lithiated organic cathode materials.

Polystyrene microplastics alter the trophic transfer and biotoxicity of fluoxetine in an aquatic food chain.

Microplastics (MPs) and fluoxetine are ubiquitous emerging pollutants in aquatic environments that may interact with each other due to the carrier effects of MPs, posing unpredictable risks to non-target organisms. However, limited studies have focused on the carrier effects of MPs in the aquatic food chain. This study evaluated the influences of polystyrene MPs on the trophic transfer and biotoxicity of fluoxetine in a simple food chain composed of brine shrimp (Artemia nauplii) and zebrafish (Danio rerio). The finding reveals that carrier effects of MPs enhanced the accumulation of waterborne fluoxetine in brine shrimp, but suppressed that in zebrafish due to the distinct retention times. The accumulated fluoxetine in shrimp was further transferred to fish through the food chain, which was alleviated by MPs due to their cleaning effects. In addition, the specific neurotransmission biotoxicity in fish induced by fluoxetine was mitigated by MPs, whilst the oxidative damage, apoptosis, and immune responses in zebrafish were reversely enhanced by MPs due to the stimulating effect. These findings highlight the alleviating effects of MPs on the trophic transfer and specific biotoxicity of fluoxetine in the food chain, providing new insights into the carrier effects of MPs in aquatic environments in the context of increasing global MP pollution.

Effect of microplastics on oxytetracycline trophic transfer: Immune, gut microbiota and antibiotic resistance gene responses.

Microplastics and antibiotics are prevalent and emerging pollutants in aquatic ecosystems, but their interactions in aquatic food chains remain largely unexplored. This study investigated the impact of polypropylene microplastics (PP-MPs) on oxytetracycline (OTC) trophic transfer from the shrimp (Neocaridina denticulate) to crucian carp (Carassius auratus) by metagenomic sequencing. The carrier effects of PP-MPs promoted OTC bioaccumulation and trophic transfer, which exacerbated enterocyte vacuolation and hepatocyte eosinophilic necrosis. PP-MPs enhanced the inhibitory effect of OTC on intestinal lysozyme activities and complement C3 levels in shrimp and fish, and hepatic immunoglobulin M levels in fish (p < 0.05). Co-exposure of MPs and OTC markedly increased the abundance of Actinobacteria in shrimp and Firmicutes in fish, which caused disturbances in carbohydrate, amino acid, and energy metabolism. Moreover, OTC exacerbated the enrichment of antibiotic resistance genes (ARGs) in aquatic animals, and PP-MPs significantly increased the diversity and abundance of ARGs and facilitated the trophic transfer of teta and tetm. Our findings disclosed the impacts of PP-MPs on the mechanism of antibiotic toxicity in aquatic food chains and emphasized the importance of gut microbiota for ARGs trophic transfer, which contributed to a deeper understanding of potential risks posed by complex pollutants on aquatic ecosystems.

Energy big data abnormal cluster detection method based on redundant convolution codec.

Due to the scattered distribution and poor clustering of abnormal clusters in energy big data, the ability to detect anomalies is poor. Therefore, a high-energy data anomaly clustering detection method based on redundant convolutional encoding is proposed. Quantitative analysis of the coupling characteristics of electrical thermal gas optical time series for multi energy users based on Copula function, and incorporating quantitative values into multi energy feature indicators to extract the energy consumption behavior characteristics of multi energy users. Utilize redundant convolutional codecs to recombine and structurally encode abnormal features of energy big data, and capture multi energy coupling time features using coupling time capsule layers. Then, coupling time features are synthesized through fully connected linear regression layers to generate anomalous clustering feature components, and the energy time series data is then transformed into feature values of the time series in three-dimensional space. Based on this, a comprehensive energy system and massive multi energy user energy big data anomaly clustering analysis are carried out to determine the optimal number of multi energy users. Then, based on linear layers, the electricity heat gas light load characteristic map of multi energy users is transformed into one-dimensional form, and an energy big data anomaly clustering detection model is constructed to complete anomaly detection. The simulation results show that the proposed method has excellent feature clustering performance, detection accuracy above 98.7%, fast convergence speed, and an error rate below 0.1, which has reliable application value.

Cotransport of nanoplastics and plastic additive bisphenol AF (BPAF) in unsaturated hyporheic zone: Coupling effects of surface functionalization and protein corona.

The ecological risk of combined pollution from microplastics (MPs) and associated contaminants usually depends on their interactions and environmental behavior, which was also disturbed by varying surface modifications of MPs. In this study, the significance of surface functionalization and protein-corona on the cotransport of nanoplastics (NPs; 100 nm) and the related additive bisphenol AF (BPAF) was examined in simulated unsaturated hyporheic zone (quartz sand; 250-425 µm). The electronegative bovine serum albumin (BSA) and electropositive trypsin were chosen as representative proteins, while pristine (PNPs), amino-modified (ANPs), and carboxyl-modified NPs (CNPs) were representative NPs with different charges. The presence of BPAF inhibited the mobility of PNPs/CNPs, but enhanced the release of ANPs in hyporheic zone, which was mainly related to their hydrophobicity changes and electrostatic interactions. Meanwhile, the NPs with high mobility and strong affinity to BPAF became effective carriers, promoting the cotransport of BPAF by 16.4 %-26.4 %. The formation of protein-coronas altered the mobility of NPs alone and their cotransport with BPAF, exhibiting a coupling effect with functional groups. BSA-corona promoted the transport of PNPs/CNPs, but this promoting effect was weakened by the presence of BPAF via increasing particle aggregation and hydrophobicity. Inversely, trypsin-corona aggravated the deposition of PNPs/CNPs, but competition deposition sites and increased energy barrier caused by coexisting BPAF reversed this effect, facilitating the cotransport of trypsin-PNPs/CNPs in hyporheic zone. However, BPAF and protein-coronas synergistically promoted the mobility of ANPs, owing to competition deposition sites and decreased electrostatic attraction. Although all of the NPs with two protein-coronas reduced dissolved BPAF in the effluents via providing deposition sites, the cotransport of total BPAF was improved by the NPs with high mobility (BSA-PNPs/CNPs) or high affinity to BPAF (BSA/trypsin-ANPs). However, the trypsin-PNPs/CNPs inhibited the transport of BPAF due to their weak mobility and adsorption with BPAF. The results provide new insights into the role of varying surface modifications on NPs in the vertical cotransport of NPs and associated contaminants in unsaturated hyporheic zone.

Solid-State Electrolytes by Electrospinning Techniques for Lithium Batteries.

Solid-state lithium batteries (SSLBs) are regarded as next-generation energy storage devices because of their advantages in terms of safety and energy density. However, the poor interfacial compatibility and low ionic conductivity seriously hinder their development. Electrospinning is considered as a promising method for fabricating solid-state electrolytes (SSEs) with controllable nanofiber structures, scalability, and cost-effectiveness. Numerous efforts are dedicated to electrospinning SSEs with high ionic conductivity and strong interfacial compatibility, but a comprehensive summary is lacking. Here, the history of electrospinning SSEs is overeviewed and introduce the electrospinning mechanism, followed by the manipulation of electrospun nanofibers and their utilization in SSEs, as well as various methods to improve the ionic conductivity of SSEs. Finally, new perspectives aimed at enhancing the performance of SSEs membranes and facilitating their industrialization are proposed. This review aims to provide a comprehensive overview and future perspective on electrospinning technology in SSEs, with the goal of guiding the further development of SSLBs.

Spin-Magnetic Effect of d-π Conjugation Polymer Enhanced O-H Cleavage in Water Oxidation.

A deep understanding of the mechanism for the spin-magnetic effect on O-H cleavage is crucial for the development of new catalysts for water oxidation. Herein, we designed and synthesized the crystalline Fe-DABDT and Co-DABDT (DABDT = 2,5-diaminobenzene-1,4-dithiol) and optimized an effective magnetic moment to explore the role of the spin-magnetic effect in the regulation of water oxidation activity. It can be found that the OER activity of the catalyst is positively correlated with its effective magnetic moment. Under the external magnetic field, Fe-DABDT with more spin single electrons has a stronger spin-magnetic response to water oxidation than Fe/Co-DABDT and Co-DABDT. The increase in OER current of Fe-DABDT is nearly 2 times higher than that of Co-DABDT. Experimental and density functional theory studies show that magnetized Fe sites could realize nucleophilic reaction, accelerate the polarization of electron spin states, and promote the polar decomposition of O-H and the formation of the O-O bond. This study provides mechanistic insight into the spin-magnetic effect of oxygen evolution reaction and further understanding of the spin origin of catalytic activity, which is expected to improve the energy efficiency of hydrogen production.

[Biological Effect of Microplastics with Different Functional Groups on the Bacterial Communities and Metabolic Functions of Zebrafish (Danio rerio) Embryos].

To investigate the influences of functional groups on the biological effects caused by microplastics, the accumulation of three polystyrene microplastics (PS, PS-NH2, and PS-COOH) in zebrafish (Danio rerio) embryos were analyzed, and then the responses of metabolic functions and microbial communities in zebrafish larvae were revealed using the combination of the microbiome and metabolome methods. The results showed that all microplastics could accumulate in zebrafish with concentrations ranging from 143 to 175 µg·g-1, and there were no significant differences in the accumulation potentials among different PS treatments. Exposure to plain PS significantly affected the metabolic capacity of aminoglycosides in zebrafish larvae, whereas the metabolic processes of amino acids were affected by PS-NH2. In the PS-COOH treatment, the metabolic pathways of the tricarboxylic acid cycle, amino acids, and glycolysis in zebrafish were markedly altered. The metabolic functions of zebrafish larvae were changed by all PS microplastics, resulting in toxic effects on zebrafish, and the functional group modification of microplastics may have further enhanced these toxicities. Compared to that in the control, exposure to PS-NH2 significantly reduced the diversity of microbial communities in zebrafish larvae and increased the proportion of Proteobacteria in the composition, leading to an imbalance of the bacterial community in zebrafish and thus disrupting the metabolic functions in the fish. Therefore, the functional modifications of microplastics may significantly alter the related stresses on aquatic organisms, leading to unpredictable ecological risks.

Hierarchical Sea Urchin-like Fe-doped Heazlewoodite for High-Efficient Oxygen Evolution.

Electrochemical water-splitting to produce hydrogen is potential to substitute the traditional industrial coal gasification, but the oxygen evolution kinetics at the anode remains sluggish. In this paper, sea urchin-like Fe doped Ni3S2 catalyst growing on nickel foam (NF) substrate is constructed via a simple two-step strategy, including surface iron activation and post sulfuration process. The NF-Fe-Ni3S2 obtains at temperature of 130 °C (NF-Fe-Ni3S2-130) features nanoneedle-like arrays which are vertically grown on the particles to form sea urchin-like morphology, features high electrochemical surface area. As oxygen evolution catalyst, NF-Fe-Ni3S2-130 exhibits excellent oxygen evolution activities, fast reaction kinetics, and superior reaction stability. The excellent OER performance of sea urchin-like NF-Fe-Ni3S2-130 is mainly ascribed to the high-vertically dispersive of nanoneedles and the existing Fe dopants, which obviously improved the reaction kinetics and the intrinsic catalytic properties. The simple preparation strategy is conducive to establish high-electrochemical-interface catalysts, which shows great potential in renewable energy conversion.

Sustainable Aqueous Batteries Based on Bipolar Dissociation of Aluminum Hydroxyacetate Electrolyte.

Rechargeable aqueous batteries are potential systems for large-scale energy storage due to their high safety and low cost. However, developing aqueous batteries with high sustainability, affordability, and reversibility is urgent and challenging. Here we report an amphoteric aluminum hydroxyacetate (AlAc(OH)2) electrolyte with the ability of bipolar ionization of H+ and OH-, which facilitates the redox reactions at both the anthraquinone (AQ) anode and nickel hydroxide (Ni(OH)2) cathode. The bipolar ionization ability of the AlAc(OH)2(H2O)3 solvation structure results from the strong polarization ability of Al3+ and OH-. The H+/OH- dissociation ability with a dissociation constant of 5.0/3.0 is stronger than that of water (14.0), which boosts the simultaneous stable redox reactions of electrodes. Specifically, H+ uptake prevents the AQ anode from the formation of an ionic bond, suppressing the electrode dissolution, whereas OH- provides the local alkaline environment for the stable conversion reaction of the Ni(OH)2 cathode. The AQ anode in the designed AQ||Ni(OH)2 battery delivers a discharge capacity of 243.9 mAh g-1 and a capacity retention of 78.2% after 300 cycles with high reversibility. Moreover, a pouch cell with a discharge capacity of 0.90 Ah was assembled, exhibiting an energy density of 44.7 Wh kg-1 based on the total mass of the battery. This work significantly widens the types of aqueous batteries and represents a design philosophy of bipolar electrolytes and distinct electrochemical reactions with H+ and OH-.

Lattice Strained Induced Spin Regulation in Co-N/S Coordination-Framework Enhanced Oxygen Reduction Reaction.

Oxygen reduction reaction (ORR) is the bottleneck of metal-air batteries and fuel cells. Strain regulation can change the geometry and adjust the surface charge distribution of catalysts, which is a powerful strategy to optimize the ORR activity. The introduction of controlled strain to the material is still difficult to achieve. Herein, we present a temperature-pressure-induced strategy to achieve the controlled lattice strain for metal coordination polymers. Through the systematic study of the strain effect on ORR performance, the relationship between geometric and electronic effects is further understood and confirmed. The strained Co-DABDT (DABDT=2,5-diaminobenzene-1,4-dithiol) with 2 % lattice compression exhibits a superior half-wave potential of 0.81 V. Theoretical analysis reveals that the lattice strain changes spin-charge densities around S atoms for Co-DABDT, and then regulates the hydrogen bond interaction with intermediates to promote the ORR catalytic process. This work helps to understand the catalytic mechanism from the atomic level.

Active Diluent-Anion Synergy Strategy Regulating Nonflammable Electrolytes for High-Efficiency Li Metal Batteries.

High-energy Li metal batteries (LMBs) consisting of Li metal anodes and high-voltage cathodes are promising candidates of the next generation energy-storage systems owing to their ultrahigh energy density. However, it is still challenging to develop high-voltage nonflammable electrolytes with superior anode and cathode compatibility for LMBs. Here, we propose an active diluent-anion synergy strategy to achieve outstanding compatibility with Li metal anodes and high-voltage cathodes by using 1,2-difluorobenzene (DFB) with high activity for yielding LiF as an active diluent to regulate nonflammable dimethylacetamide (DMAC)-based localized high concentration electrolyte (LHCE-DFB). DFB and bis(fluorosulfonyl)imide (FSI- ) anion cooperate to construct robust LiF-rich solid electrolyte interphase (SEI) and cathode electrolyte interphase (CEI), which effectively stabilize DMAC from intrinsic reactions with Li metal anode and enhance the interfacial stability of the Li metal anodes and LiNi0.8 Co0.1 Mn0.1 O2 (NCM811) cathodes. LHCE-DFB enables ultrahigh Coulombic efficiency (98.7 %), dendrite-free, extremely stable and long-term cycling of Li metal anodes in Li || Cu cells and Li || Li cells. The fabricated NCM811 || Li cells with LHCE-DFB display remarkably enhanced long-term cycling stability and excellent rate capability. This work provides a promising active diluent-anion synergy strategy for designing high-voltage electrolytes for high-energy batteries.

A state-of-the-art review on biomass-derived carbon materials for supercapacitor applications: From precursor selection to design optimization.

Biomass-derived carbon materials have the characteristics of a wide range of precursor sources, controllable carbon nano-dimension, large specific surface area and abundant heteroatoms doping. At present, biomass-derived carbon materials have been widely used in electrochemical energy storage devices, especially the research and development of biomass-derived carbon materials for supercapacitors has become mature and in-depth. Therefore, it is of importance to summarize the advanced technologies and strategies for optimizing biomass-derived carbon materials for supercapacitors, which will effectively promote the further development of high-performance supercapacitors. In this review, the recent research progress of biomass-derived carbon materials is provided in detail, including the selection of biomass precursors, the design of carbon nano-dimension and the theory of heteroatom doping. Besides, the preparation methods of biomass-derived carbon materials and the related processes of optimizing the electrochemical performance are also summarized. This review ends with the perspectives for future research directions and challenges in the field of biomass-derived carbon materials for electrochemical applications. This review aims to provide helpful reference information for the nano-dimensional design and electrochemical performance optimization of biomass-derived carbon materials for the practical application of supercapacitors.

Suppressing Bulk Strain and Surface O2 Release in Li-Rich Cathodes by Just Tuning the Li Content.

Layered oxides represent a prominent class of cathodes employed in lithium-ion batteries. The structural degradation of layered cathodes causes capacity decay during cycling, which is generally induced by anisotropic lattice strain in the bulk of cathode particle and oxygen release at the surface. However, particularly in lithium-rich layered oxides (LLOs) that undergo intense oxygen redox reactions, the challenge of simultaneously addressing bulk and surface issues through a singular modification technique remains arduous. Here a thin (1-nm) and coherent spinel-like phase is constructed on the surface of LLOs particle to suppress bulk strain and surface O2 release by just adjusting the amount of lithium source during synthesis. The spinel-like phase hinders the surface O2 release by accommodating O2 inside the surface layer, while the trapped O2 in the bulk impedes strain evolution by ≈70% at high voltages compared with unmodified LLOs. Consequently, the enhanced structural stability leads to an improved capacity retention of 97.6% and a high Coulombic efficiency of ≈99.5% after 100 cycles at 0.1°C. These findings provide profound mechanistic insights into the functioning of surface structure and offer guidance for synthesizing high-capacity cathodes with superior cyclability.

Dynamic evolution of antibiotic resistance genes in plastisphere in the vertical profile of urban rivers.

Microplastics (MPs) can vertically transport in the aquatic environment due to their aging and biofouling, forming distinct plastisphere in different water layers. However, even though MPs have been regarded as hotspots for antibiotic resistance genes (ARGs), little is known about the propagation and transfer of ARGs in plastisphere in waters, especially in the vertical profile. Therefore, this study investigated the dynamic responses and evolution of ARGs in different plastisphere distributed vertically in an urbanized river. The biofilm biomass in the polylactic acid (PLA) plastisphere was relatively higher than that in the polyethylene terephthalate (PET), showing depth-decay variations. The ARGs abundance in plastisphere were much higher than that in the surrounding waters, especially for the PLA. In the vertical profiles, the ARGs abundance in the PET plastisphere increased with water depths, while the highest abundance of ARGs in the PLA mostly appeared at intermediate waters. In the temporal dynamic, the ARGs abundance in plastisphere increased and then decreased, which may be dominated by the MP types at the initial periods. After long-term exposure, the influences of water depths seemed to be strengthened, especially in the PET plastisphere. Compared with surface waters, the microbiota attached in plastisphere in deep waters showed high species richness, strong diversity, and complex interactions, which was basically consistent with the changes of nutrient contents in different water layers. These vertical variations in microbiota and nutrients (e.g., nitrogen) may be responsible for the propagation of ARGs in plastisphere in deep waters. The host bacteria for ARGs in plastisphere was also developed as water depth increased, leading to an enrichment of ARGs in deep waters. In addition, the abundance of ARGs in plastisphere in bottom waters was positively correlated with the mobile genetic elements (MGEs) of intI1 and tnpA05, indicative of a frequent horizontal gene transfer of ARGs. Overall, water depth played a critical role in the propagation of ARGs in plastisphere, which should not be ignored in a long time series. This study provides new insights into the dynamic evolution of ARGs propagation in plastisphere under increasing global MPs pollution, especially in the vertical profile.

Co-exposure of microplastics and sulfamethoxazole propagated antibiotic resistance genes in sediments by regulating the microbial carbon metabolism.

The concerns on the carriers of microplastics (MPs) on co-existing pollutants in aquatic environments are sharply rising in recent years. However, little is known about their interactions on the colonization of microbiota, especially for the spread of pathogens and antibiotic resistance genes (ARGs). Therefore, this study aimed to investigate the influences on the propagation of ARGs in sediments by the co-exposure of different MPs and sulfamethoxazole (SMX). The results showed that the presence of MPs significantly enhanced the contents of total organic carbon, while having no effects on the removal of SMX in sediments. Exposure to SMX and MPs obviously activated the microbial carbon utilization capacities based on the BIOLOG method. The propagation of ARGs in sediments was activated by SMX, which was further promoted by the presence of polylactic acid (PLA) MPs, but significantly lowered by the co-exposed polyethylene (PE) MPs. This apparent difference may be attributed to the distinct influence on the antibiotic efflux pumps of two MPs. Moreover, the propagation of ARGs may be also dominated by microbial carbon metabolism in sediments, especially through regulating the carbon sources of carboxylic acids, carbohydrates, and amino acids. This study provides new insights into the carrier effects of MPs in sediments.

Asymmetric Solvents Regulated Crystallization-Limited Electrolytes for All-Climate Lithium Metal Batteries.

Electrolytes that can keep liquid state are one of the most important physical metrics to ensure the ions transfer with stable operation of rechargeable lithium-based batteries at a wide temperature window. It is generally accepted that strong polar solvents with high melting points favor the safe operation of batteries above room temperatures but are susceptible to crystallization at low temperatures (≤-40 °C). Here, a crystallization limitation strategy was proposed to handle this issue. We demonstrate that, although the high melting points of ethylene sulfite (ES, -17 °C) and fluoroethylene carbonate (FEC, ≈23 °C), their mixtures can avoid crystallization at low temperatures, which can be attributed to low intermolecular interactions and altered molecular motion dynamics. A suitable ES/FEC ratio (10 % FEC) can balance the bulk and interface transport of ions, enabling LiNi0.8 Mn0.1 Co0.1 O2 ||lithium (NCM811||Li) full cells to deliver excellent temperature resilience and cycling stability over a wide temperature range from -50 °C to +70 °C. More than 66 % of the capacity retention was achieved at -50 °C compared to room temperature. The NCM811||Li pouch cells exhibit high cycling stability under realistic conditions (electrolyte weight to cathode capacity ratio (E/C)≤3.5 g Ah-1 , negative to positive electrode capacity ratio (N/P)≤1.09) at different temperatures.

Directional electronic tuning of Ni nanoparticles by interfacial oxygen bridging of support for catalyzing alkaline hydrogen oxidation.

Metallic nickel (Ni) is a promising candidate to substitute Pt-based catalysts for hydrogen oxidation reaction (HOR), but huge challenges still exist in precise modulation of the electronic structure to boost the electrocatalytic performances. Herein, we present the use of single-layer Ti3C2Tx MXene to deliberately tailor the electronic structure of Ni nanoparticles via interfacial oxygen bridges, which affords Ni/Ti3C2Tx electrocatalyst with exceptional performances for HOR in an alkaline medium. Remarkably, it shows a high kinetic current of 16.39 mA cmdisk-2 at the overpotential of 50 mV for HOR [78 and 2.7 times higher than that of metallic Ni and Pt/C (20%), respectively], also with good durability and CO antipoisoning ability (1,000 ppm) that are not available for conventional Pt/C (20%) catalyst. The ultrahigh conductivity of single-layer Ti3C2Tx provides fast transmission of electrons for Ni nanoparticles, of which the uniform and small sizes endow them with high-density active sites. Further, the terminated -O/-OH functional groups on Ti3C2Tx directionally capture electrons from Ni nanoparticles via interfacial Ni-O bridges, leading to obvious electronic polarization. This could enhance the Nids-O2p interaction and weaken Nids-H1s interaction of Ni sites in Ni/Ti3C2Txenabling a suitable H-/OH-binding energy and thus enhancing the HOR activity.

Toxicity comparison of perfluorooctanoic acid (PFOA), hexafluoropropylene oxide dimer acid (HFPO-DA), and hexafluoropropylene oxide trimer acid (HFPO-TA) in zebrafish gut.

Hexafluoropropylene oxide dimer acid (HFPO-DA) and hexafluoropropylene oxide trimer acid (HFPO-TA) are considered as alternatives to perfluorooctanoic acid (PFOA). In this study, zebrafish were exposed to different concentrations of PFOA, HFPO-DA, and HFPO-TA (5 µg/L and 500 µg/L), and the toxic effects on oxidative damage, inflammation, and cell apoptosis in the gut were compared. Additionally, changes in gut metabolome profiles and microbial community structure were analyzed. The results revealed that exposures to HFPO-DA and HFPO-TA led to lower levels of oxidative damage compared to PFOA exposure. However, all three treatments had comparable effects on inflammation and apoptosis. The main biological pathways affected by all three exposures were lipid metabolism, nucleotide metabolism, amino acid metabolism, and environmental information processing. The effects on metabolome profiles were much higher for HFPO-DA and HFPO-TA compared to PFOA at a concentration of 5 µg/L. At a concentration of 500 µg/L, HFPO-DA and HFPO-TA showed similar effects to PFOA. This study also examined the Pearson correlations between gut microbiota and the toxic effects mentioned above. The abundance of specific apoptosis-related genera differed among the three target chemicals, suggesting they may act differently in inducing apoptosis. The correlations between HFPO-DA and HFPO-TA were mostly similar, which helps explain the similar effects observed in their respective treatment groups on metabolic profiles. Overall, this study indicates that HFPO-DA and HFPO-TA may not be safe alternatives to PFOA and provides valuable insights into their toxic effects and risk assessment in water environments.

mfeeU-Net: A multi-scale feature extraction and enhancement U-Net for automatic liver segmentation from CT Images.

Medical image segmentation of the liver is an important prerequisite for clinical diagnosis and evaluation of liver cancer. For automatic liver segmentation from Computed Tomography (CT) images, we proposed a Multi-scale Feature Extraction and Enhancement U-Net (mfeeU-Net), incorporating Res2Net blocks, Squeeze-and-Excitation (SE) blocks, and Edge Attention (EA) blocks. The Res2Net blocks which are conducive to extracting multi-scale features of the liver were used as the backbone of the encoder, while the SE blocks were also added to the encoder to enhance channel information. The EA blocks were introduced to skip connections between the encoder and the decoder, to facilitate the detection of blurred liver edges where the intensities of nearby organs are close to the liver. The proposed mfeeU-Net was trained and evaluated using a publicly available CT dataset of LiTS2017. The average dice similarity coefficient, intersection-over-union ratio, and sensitivity of the mfeeU-Net for liver segmentation were 95.32%, 91.67%, and 95.53%, respectively, and all these metrics were better than those of U-Net, Res-U-Net, and Attention U-Net. The experimental results demonstrate that the mfeeU-Net can compete with and even outperform recently proposed convolutional neural networks and effectively overcome challenges, such as discontinuous liver regions and fuzzy liver boundaries.