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This study evaluated the synergistic antibacterial mechanism of ultrasound (US) and rosmarinic acid (RA) treatment on large yellow croaker during cold storage (4 °C). The results indicated that the synergistic treatment of US + RA can significantly reduce TVB-N and TCA-soluble peptide and decrease protein decomposition and oxidation in large yellow croaker during storage, and thus significantly delay the growth of microorganisms. In addition, the representative strains of Shewanella baltica and Carnobacterium maltaromaticum were isolated from the decaying yellow croaker, and the antibacterial mechanism of the combination of US + RA was determined. Compared with Carnobacterium maltaromaticum , the synergistic treatment of US + RA has a more significant impact on the membrane structure of the Shewanella baltica , which exacerbates the leakage of nucleic acid and protein in the Shewanella baltica and effectively inhibits its respiratory metabolic activity. This result provides evidence for the antibacterial mechanism and preservation ability of the combination of US + RA. • The US + RA treatment can significantly reduce the degree of oxidative denaturation of lipids. • The US + RA treatment can significantly reduce the degree of oxidative denaturation of proteins. • The US + RA treatment can significantly delay the growth of microorganisms. • The synergistic treatment of US + RA has a more significant impact on the membrane structure of the Shewanella baltica. [ABSTRACT FROM AUTHOR]

Ibuprofen (IBU), as a commonly used non-steroidal anti-inflammatory drug (NSAID) and pharmaceutical and personal care product (PPCP), is frequently prescribed by doctors to relieve pain. It is widely released into environmental water and soil in the form of chiral enantiomers by the urination and defecation of humans or animals and by sewage discharge from wastewater treatment plants. This study focused on the alteration of metabolism in the adult zebrafish ( Danio rerio ) brain after exposure to R-(-)-/S-(+)-/rac-IBU at 5 μg L −1 for 28 days. A total of 45 potential biomarkers and related pathways, including amino acids and their derivatives, purine and its derivatives, nucleotides and other metabolites, were observed with untargeted metabolomics. To validate the metabolic disorders induced by IBU, 22 amino acids and 3 antioxidant enzymes were selected to be quantitated and determined using targeted metabolomics and enzyme assay. Stereoselective changes were observed in the 45 identified biomarkers from the untargeted metabolomics analysis. The 22 amino acids quantitated in targeted metabolomics and 3 antioxidant enzymes determined in enzyme assay also showed stereoselective changes after R-(-)-/S-(+)-/rac-IBU exposure. Results showed that even at a low concentration of R-(-)-/S-(+)-/rac-IBU, disorders in metabolism and antioxidant defense systems were still induced with stereoselectivity. Our study may enable a better understanding of the risks of chiral PPCPs in aquatic organisms in the environment. [ABSTRACT FROM AUTHOR]

The diamides have become one of the most promising new classes of insecticides. In this study, we evaluated the toxicity of three diamides (chlorantraniliprole, cyantraniliprole and flubendiamide) to Daphnia magna . The acute toxicity test showed that the 48-h EC 50 of chlorantraniliprole, cyantraniliprole and flubendiamide were 8.5, 23.9 and 63.5 μg/L, respectively. Biochemical measurements revealed a significant increase in reactive oxygen species (ROS) in D. magna after acute exposure to the three diamides. A significant decrease in activities of antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) was observed, which was consistent with the down-regulated transcription of antioxidant genes sod and gpx . Catalase (CAT) activity exhibited a significant increase while the related gene cat showed no obvious change in daphnids acutely exposed to the three diamides. The chronic test revealed that the three diamides could cause lethal and sub-lethal effects on daphnids within constricted range of concentrations at μg/L level. The 21-d EC 50 of chlorantraniliprole, cyantraniliprole and flubendiamide for mobility were 5.0, 13.6 and 36.8 μg/L, respectively. The chronic LOEC of chlorantraniliprole, cyantraniliprole and flubendiamide based on survival, growth and reproduction of D. magna were 4.05, 10.24 and 19.36 μg/L, respectively. Moreover, these three diamides can induce severe developmental abnormalities in D. magna embryos including underdeveloped second antennae, curved tail spine and abnormal body region after acute exposure and the 48-h EC 50 were 6.2, 14.1 and 30.8 μg/L for chlorantraniliprole, cyantraniliprole and flubendiamide respectively. Our findings indicate that even low levels of diamides can pose ecological risks to aquatic ecosystems. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the oxidative stress process and bioaccumulation the racemic/(−)-/(+)- 2,2ʹ,3,4ʹ,6-pentachlorobiphenyl were administered to adult zebrafish ( Danio rerio ) after prolonged exposure of 56-days uptake and 49-days depuration experiments. Stereoselective accumulation was observed in adult samples after racemic exposure as revealed by decreased enantiomer fractions. The two enantiomers of PCB91 accumulated at different rates with logBCF k values close to 3.7, suggesting that they were highly hazardous and persistent pollutants. Exposure to racemic/(−)-/(+)- PCB91 stereoselectively induced oxidative stress owing to changes in reactive oxygen species, malondialdehyde contents, antioxidant enzyme activities and gene expressions in brain and liver tissues. In addition, the stereoselective relationship between bioconcentration and oxidative stress were also presented in this study. Our findings might be helpful for elucidating the environmental risk of the two enantiomers of PCB91 that induce toxicity in aquatic organisms. [ABSTRACT FROM AUTHOR]

Difenoconazole is a widely used triazole fungicide and has been reported to have negative impacts on zebrafish embryos. To investigate the mechanism of its developmental toxicity, zebrafish embryos were exposed to 0.5 and 2.0 mg/L difenoconazole for 96 h. The morphological and physiological indicators of embryo development were tested. The total cholesterol (TCHO) level, triglyceride (TG) level and malondialdehyde (MDA) content were measured at 96 hpf (hours post-fertilization). In addition, the transcription of genes related to embryo development, the antioxidant system, lipid synthesis and metabolism was quantified. Our results showed that a large suite of symptoms were induced by difenoconazole, including hatching regression, heart rate decrease, growth inhibition and teratogenic effects. 0.5 mg/L difenoconazole could significantly increase the TG content of zebrafish embryos at 96 hpf, while no apparent change in the TCHO and MDA level was observed post 96 h exposure. Q-PCR (quantitative real-time polymerase chain reaction) results showed that the transcription of genes related to embryonic development was decreased after exposure. Genes related to hatching, retinoic acid metabolism and lipid homeostasis were up-regulated by difenoconazole. [ABSTRACT FROM AUTHOR]

Finger-vein recognition has been widely explored for biometrics security over the past two or three decade. Its size and characteristics against presentation attacks make it suitable for various commercial, governmental and forensics applications. As with other biometric traits, finger-vein recognition approaches mainly depend on well-engineering feature descriptors and recently, more deep learning (DL) models have been designed to achieve high-performance biometrics. However, the existing DL approaches usually employ the neural networks with increasing layers and parameters, which inevitably leads to an increase in memory consumption and algorithm complexity. Besides, all the vein recognition networks use square filters, which are influenced by network designed for object detection and classification. In this paper, two network design issues for finger-vein recognition are explored: shallow network using rectangular filters and lightweight semi-pretrained network. The exhaustive experiments on three benchmark databases HKPU, FV-USM and SDUMLA demonstrate that rectangular filters outperform square filters for DL-based finger-vein recognition, and the lightweight semi-pretrained network also outperforms non-pretrained network. [ABSTRACT FROM AUTHOR]

Mefentrifluconazole is a new chiral triazole fungicide with high efficiency and broad spectrum. Zebrafish embryos, larvae and adults were exposed to mefentrifluconazole racemate and enantiomers to investigate aquatic toxicity of mefentrifluconazole at the enantiomer level. Acute toxicity tests were conducted to determine the lethality of mefentrifluconazole. The developmental toxicity of mefentrifluconazole to embryos and larvae was also assessed during acute exposure. Besides, the growth parameters of adults were evaluated after 14 days' exposure. The 96-h LC 50 ranges of rac-, R-(−)- and S-(+)-mefentrifluconazole to all zebrafish life-stages were 0.753–1.198, 1.092–2.022 and 0.583–1.056 mg/L respectively. Larvae were the most sensitive to mefentrifluconazole in terms of lethality, followed by embryos and adults. During acute exposure, morphological deformities caused by mefentrifluconazole, such as yolk sac edema and pericardial edema in embryos, as well as pericardial edema and spinal curvature in larvae were discovered. Besides, mefentrifluconazole induced significant developmental defects, including inhibited heartbeat and reduced body length in both embryos and larvae. After 14 days' mefentrifluconazole exposure, severe growth inhibition in adult zebrafish was observed. Mefentrifluconazole shows enantioselective toxicity in all stages of zebrafish, and the order of toxicity is S-(+)-mefentrifluconazole > rac-mefentrifluconazole > R-(−)-mefentrifluconazole. Further study is required to explore the specific enantioselective mechanism. Our findings enable a better understanding of the potential risk of mefentrifluconazole to aquatic ecosystems at the enantiomer level. [Display omitted] • Mefentrifluconazole showed strong lethality to zebrafish. • Mefentrifluconazole induced severe developmental effects on multiple stages of zebrafish. • S-(+)-mefentrifluconazole exerted higher toxicity to zebrafish than R-(−)-mefentrifluconazole. [ABSTRACT FROM AUTHOR]

Cyhalofop-butyl is a selective herbicide widely employed in paddy field, which can transfer into aquatic environments. However, details of the environmental risk and aquatic toxicity of cyhalofop-butyl have not been fully investigated. In this study, zebrafish ( Danio rerio ) embryos were exposed to a range of cyhalofop-butyl until 120 hour post-fertilization (hpf) to assess embryonic toxicity of the chemical. Our results demonstrated that cyhalofop-butyl was highly toxic to zebrafish embryos, with concentration-dependent negative effects in embryonic development. In addition, exposure to cyhalofop-butyl resulted in significant increases in reactive oxygen species (ROS) production and cell apoptosis in heart area. The mRNA levels of the genes related to oxidative stress and apoptosis were also altered significantly after cyhalofop-butyl exposure. Moreover, the activity of capspase-9 and caspase-3 were significantly increased. Therefore, we speculated that oxidative stress-induced apoptosis should be responsible for abnormal development during embryogenesis after cyhalofop-butyl exposure. [ABSTRACT FROM AUTHOR]

We report here an investigation of the mechanisms contributing to the divergent sensitivity toward the triazole fungicide difenoconazole of zebrafish ( Danio reio ) during different life stages. Adult and embryonic zebrafish were exposed to three different concentrations of difenoconazole (0.01, 0.5 and 1.0 mg/L). The death rate, bioaccumulation of difenoconazole, oxidative stress parameters and transcription of related genes were tested at 4 and 8 days post-exposure (dpe). The death rate for adult zebrafish was much higher than that of the embryos at an exposure concentration of 1.0 mg/L at both 4 and 8 dpe. The concentrations of difenoconazole in both the embryos and adult fish were similar, except for the group exposed to 0.01 mg/L difenoconazole. A decrease in antioxidant enzyme activities was observed in both the embryos and the livers of adult fish after exposure to difenoconazole. Significant lipid peroxidation was found in the livers of adult fish in all exposure groups at 8 dpe, but was not observed in the treated embryos. The gene transcription response of the embryos toward difenoconazole was different from that in the livers of adult fish at 4 dpe. At 8 dpe, the modification in the transcription of the tested genes in the embryos and adult fish was similar, except for the genes related to the synthesis of sterols. [ABSTRACT FROM AUTHOR]

Fluoxetine is frequently detected in aquatic environment, and chronic FLX exposure exhibits adverse effects on aquatic communities. Its chirality makes the adverse effects more complicated. This study aimed at the enantioselective cardiotoxicity in developmental zebrafish induced by racemic (rac-)/S-/R-fluoxetine. The accumulation profiles demonstrated that biotransformation of fluoxetine to norfluoxetine occurred during rac-fluoxetine exposure, with a higher enrichment of S-norfluoxetine than R-norfluoxetine. Heart malformations including pericardial edema, circulation abnormalities, and thrombosis were observed, and enantioselective changes also occurred. According to H&E staining and Masson's trichrome staining, the loose severity of cardiac structure and cardiac fibrosis in rac-norfluoxetine treated group was worse than that in fluoxetine treated groups. Results of toxicity-associated parameters in our homochiral enantiomers' exposure also indicated that the toxicity induced by S-fluoxetine was more severe than R-fluoxetine. Enantioselective arrhythmia in developmental zebrafish after chiral fluoxetine exposure could be caused by myocardial fibrosis, abnormal developmental processes, and the biotransformation of fluoxetine to norfluoxetine could make that worse. Our findings can be used to assess the environmental risk of the two enantiomers of fluoxetine that induce cardiotoxicity in aquatic organisms. Image 1 • Chiral fluoxetine exposure induced enantioselective arrhythmia in developmental zebrafish. • Biotransformation of fluoxetine to norfluoxetine could make arrhythmia worse. • Higher enrichment of S-norfluoxetine was observed during rac-fluoxetine exposure. • Cardiotoxicity induced by S-fluoxetine were more severe than R-fluoxetine. [ABSTRACT FROM AUTHOR]

Text classification first needs to convert the text into embedding vectors. Considering that static word embedding models such as Word2vec do not consider the position information of word and the difference of its role in different documents, while dynamic word embedding models such as Bert consume a large amount of time. An improved word embedding model based on pre-trained Word2vec is proposed, which achieves better classification accuracy and much lower classification time than Bert. At first, the concept of Term Document Frequency (TDF) is proposed on the basis of TF-IDF, and the TF-IDF-TDF of each word in different documents is calculated. Then, The positional encoding is added. Finally, in order to reduce the misleading of words with low importance, a filter is designed to set the embedding vector with low importance to zero. Considering that the sequence length that the deep learning model can handle is limited, and the text sequence exceeding the Maximum Sequence Length (MSL) set by the deep learning model will be directly truncated and discarded, an adaptive segmentation model is proposed, which can set different segmentation strategies for different texts according to the length of the text and the MSL. In order to maintain the continuity of adjacent text after segmentation, an adjacent-segment-vector-attended co-attention network is designed. In addition, the multi-channel convolution and the capsule network are designed to further extract deep hidden features. Multiple comparative experiment results show that the proposed model achieves the best Accuracy and Micro-F1 on five long text baseline datasets and six short text baseline datasets. In addition, when the MSL is not set too large compared with the document length in the dataset, the classification results of the proposed model are not affected by it. • An pre-trained Word2vec based embedding model is proposed. • An adaptive segmented text classification model is proposed. • An adjacent-segment-vector-attended co-attention network is designed. • The multi-channel convolution and capsule network are used to extract deep hidden features. [ABSTRACT FROM AUTHOR]

The stereoselective effects of chiral ibuprofen (IBU) were studied using lipidomics by exposing adult zebrafish (Danio rerio) to an environmental concentration of 5 μg/L for 28 days. After treatment with rac-/ R -(−)-/ S -(+)-IBU, the brain tissue of the zebrafish was harvested to analyze for lipid metabolites by using ultra-performance liquid chromatography–quadrupole time-of-flight mass spectrometry. Results showed that the six classes of lipids, namely, glycerophospholipids, sterol lipids, prenol lipids, fatty acyls, glycerolipids, and sphingolipids, including 46 biomarkers, were affected after exposure. The different influences on metabolites were observed in the rac-/ R -(−)-/ S -(+)-IBU-treated samples. The rac-IBU treatment remarkably affected nine lipids. The R -(−)-IBU and S -(+)-IBU treatments had remarkably effects on six and four lipids, respectively. According to the HMDB database and KEGG pathways, nine important lipids were successfully matched to the involved biochemical pathways, such as glycerophospholipid metabolism, arachidonic acid metabolism, and linoleic acid metabolism. Therefore, IBU can cause disorders in the metabolism of the brain lipids of adult zebrafish and affect the composition of biological membranes, inflammatory responses, and cardiovascular and cerebrovascular diseases. The significant difference in the effects of R -(−)-IBU and S -(+)-IBU on lipidomics indicated that chiral IBU has stereoselective toxicity to aquatic organisms. Our study provided new insights into the environmental toxicology and highlighted the hazard of pharmaceutical and personal care product pollution in aquatic environments. Unlabelled Image • Lipidomic perturbations were induced in adult zebrafish after IBU exposure at 5 μg/L. • Forty-six potential biomarkers were identified in zebrafish brain after exposure. • The alterations of lipid metabolites indicate stereoselective effects of chiral IBU. • PC and PS were respectively involved in 9 and 5 biochemical pathways. [ABSTRACT FROM AUTHOR]

• Ultrasound increased free amino acids and nucleotides contents in the semi-dried fish. • Heat treatment would promote the production of volatile substances. • Na+ and K+ played an important role in flavor characteristics of semi-dried fish. • Partial substitution of KCl for NaCl could improve the flavor. • Coordination treatment was beneficial to improve the flavor. This study investigated the flavor characteristics of semi-dried yellow croaker made by KCl instead of partial NaCl combined with ultrasound treatment before and after low temperature vacuum heating. The electronic tongue, electronic nose, free amino acids, 5′-nucleotides, and gas chromatography-ion mobility spectrometry were employed. Electronic nose and electronic tongue results showed that different treatment groups had different sensitive signals to smell and taste. The odor and taste of each group were mainly affected by Na+ and K+. The difference between the groups becomes larger after thermal treatment. Ultrasound and thermal treatment both changed the content of taste components. In addition, each group contained 54 volatile flavor compounds. Among them, the combined treatment method gave semi-dried large yellow croaker pleasant flavor characteristics. Besides, it also improved the content of flavor substances. In conclusion, the semi-dried yellow croaker under sodium-reduced conditions showed better performance in flavor characteristics. [ABSTRACT FROM AUTHOR]

To construct a rapid read-out analytical platform for detecting histamine in foods, a self-visualization nanomaterial was prepared by stable doping of ninhydrin into TiO 2 nanoparticles (ninhydrin@TiO 2) using a sol-gel strategy, and it was printed onto the target zone for histamine on a high-performance thin layer chromatography (HPTLC) strip based on the Rf value. Under the optimum TLC conditions, histamine in the sample migrates to the target zone, and the colorimetric reaction occurs in situ. The resultant color spots can be either identified visually or semi-quantitatively by image analysis. Owing to the stable visualization performance, the constructed strip demonstrated good contrast, with a low background and easily recognizable colored spots. The linear range was 15.0–320.0 mg kg−1, and the limit of detection for histamine in fish was 5.0 mg kg−1. Other biogenic amines such as putrescine and cadaverine did not interfere with the analysis. Furthermore, analytical results for fish samples were verified by HPLC tests, demonstrating the robustness and reliability of the developed method. Therefore, the incorporation of a self-visualization nanomaterial in the HPTLC platform is a promising strategy for the rapid analysis of food contaminants in the future. • A new thin-layer chromatographic (TLC) visualization methodology was developed. • Novel self-visualization nanomaterial ninhydrin@TiO 2 was successfully synthesized. • Histamine can be analyzed in aquatic products with sensitivity and rapidness. [ABSTRACT FROM AUTHOR]