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Heavy metal copper (Cu) will inevitably impact the marine macroalgae Gracilariopsis lemaneiformis (G. lemaneiformis), which is a culture of economic importance along China's coastline. In this study, the detoxification mechanism of Cu stress on G. lemaneiformis was revealed by assessing physiological indicators in conjunction with transcriptome and metabolome analyses at 1 d after Cu stress. Our findings revealed that 25 μM Cu stimulated ROS synthesis and led to the enzymatic oxidation of arachidonic acid residues. This process subsequently impeded G. lemaneiformis growth by suppressing photosynthesis, nitrogen metabolism, protein synthesis, etc. The entry of Cu ions into the algae was facilitated by ZIPs and IRT transporters, presenting as Cu2+. Furthermore, there was an up-regulation of Cu efflux transporters HMA5 and ABC family transporters to achieve compartmentation to mitigate the toxicity. The results revealed that G. lemaneiformis elevated the antioxidant enzyme superoxide dismutase and ascorbate-glutathione cycle to maintain ROS homeostasis. Additionally, metabolites such as flavonoids, 3-O-methylgallic acid, 3-hydroxy-4-keto-gama-carotene, and eicosapentaenoic acid were up-regulated compared with the control, indicating that they might play roles in response to Cu stress. In summary, this study offers a comprehensive insight into the detoxification mechanisms driving the responses of G. lemaneiformis to Cu exposure. [ABSTRACT FROM AUTHOR]

In China, most of the high-sulfur iron ores have not been fully developed and utilized due to the lack of breakthrough progress in the research on the sulfur migration and the desulfurization mechanism during the roasting process. This study will focus on revealing the release and fixation mechanisms of sulfur during the roasting process to achieve the transformation of desulfurization from terminal treatment to process control. Experimental results show that as the roasting temperature increases, the release rate of SO2 also increases, reaching the maximum release rate at 900 °C. Simultaneously, it is found that at the same roasting temperature, the release rate and amount of SO2 under the O2/N2 atmosphere is significantly greater than that under the pure N2 and air atmospheres. Meanwhile, X-ray diffraction (XRD) is utilized to explore the phase composition of the roasted product and the sulfur release mechanism. In addition, the adsorption energy, stability and electron transfer of SO2 on the CaO surface are calculated through density functional theory (DFT), and the optimal adsorption active site perpendicular to the O atom (O-top) is also determined. Finally, the sulfur fixing agent CaO is used to study the SO2 fixation mechanism. When the concentration reaches 10%, the sulfur fixation efficiency reaches more than 80%. Therefore, this work will present basic knowledge and systematic guidance for the sulfur migration and release of high-sulfur iron ore under the oxidizing roasting process. [ABSTRACT FROM AUTHOR]

Significant efforts have been made in recent years to produce healthier wines, with the primary goal of reducing the use of sulfur dioxide (SO2), which poses health risks. This study aimed to assess the effectiveness of three plant-derived polyphenols (dihydromyricetin, resveratrol, and catechins) as alternatives to SO2 in wine. After a three-month aging process, the wines were evaluated using analytical techniques such as high-performance liquid chromatography, colorimetry, gas chromatography–olfactometry–mass spectrometry, as well as electronic nose and electronic tongue analyses, with the purpose to assess parameters including antioxidant activity, color, contents of volatile aroma compounds, and sensory characteristics. The results demonstrated various degrees of improvement in the antioxidant activity, aromatic intensity, and sensory characteristics of wines using polyphenols. Notably, dihydromyricetin (200 mg/L) exhibited the strongest antioxidant activity, with increases of 18.84%, 23.28%, and 20.87% in 2,2-diphenyl-1-picrylhydrazyl, 2,2'azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), and ferric-ion-reducing antioxidant power assays, respectively. Resveratrol (200 mg/L) made the most significant contribution to volatile aroma compounds, with an 8.89% increase in the total content of alcohol esters. In E-nose analysis, catechins (200 mg/L) showed the highest response to aromatic compounds and the lowest response to volatile sulfur compounds, while also exhibiting the best sensory characteristics. Therefore, the three plant-derived polyphenols investigated here exhibited the potential to enhance wine quality as alternatives to SO2. However, it is important to consider the specific impact of different polyphenols on wine; hence, suitable antioxidants should be selected in wine production according to specific requirements. [ABSTRACT FROM AUTHOR]

With high real-time performance and a good filtering effect, the wavelet transform-based real-time filter is more commonly used in the fusion magnet power supply. Considering the signal characteristics of the fusion magnet power supply, the sliding time window method is widely used to satisfy the requirements of filtering efficiency. In this paper, an updated half-edge extension method is proposed to improve the boundary effect of sliding window data. Moreover, the hardware-based wavelet loopback structure is proposed to avoid the double computation of long sliding window data, thereby improving real-time performance and satisfying the demands of fusion magnet power supply filtering. The proposed half-edge extension method and the wavelet loopback structure are implemented by designed FPGA and experimented on the Experimental and Advanced Superconducting Tokamak (EAST) fusion magnet power supply system to verify the filtering efficiency. According to the experiment's results, the proposed half-edge extension method has a better filtering effect, and the proposed wavelet loopback structure decreases the time by 67.4%, which can satisfy the requirements of the power supply system. [ABSTRACT FROM AUTHOR]

This work aims to evaluate the effect of ferulic acid-grafted chitosan (FA-g-CS) on the interaction between anthocyanin (ANC) and sGLT1/GLUT2 and their functions in ANC transmembrane transport using Caco-2 cells. The transmembrane transport experiments of ANC showed its low transport efficiency (Papp < 10−6 cm/s), whereas the phenomenon of a significantly rise in anthocyanins transport efficiency was observed with the incubation of FA-g-CS (p < 0.05). In order to investigate the mechanism of FA-g-CS improving ANC transmembrane transport, Caco-2 cells were transfected with small interfering RNA (siRNA) specific for transporters sGLT1 and GLUT2, and incubated with ANC, FA-g-CS, or their combination. Subsequently, Western blot analyses and immunofluorescence staining were carried out to monitor the intracellular sGLT1 and GLUT2 levels. These siRNA-transfected cells, incubated with compounds, indicate that sGLT1 and GLUT2 participated in the ANC transmembrane transport and that FA-g-CS, ANC, or their combination enhance sGLT1/GLUT2 expression. In particular, Caco-2 cells incubated with both FA-g-CS and ANC show significantly increased sGLT1 or GLUT2 expression (>80%) compared with exclusively using FA-g-CS or ANC (<60%). Molecular docking results demonstrate that there is a good binding between FA-g-CS/ANC and sGLT1 or GLUT2. These results highlight that FA-g-CS promotes the transmembrane transport of ANC by influencing the interaction between ANC and sGLT1/GLUT2; the interaction between FA-g-CS and ANC could be another key factor that improves the bioavailability of ANC. [ABSTRACT FROM AUTHOR]

Agar is widely applied across the food, pharmaceutical and biotechnology industries, owing to its various bioactive functions. To better understand the agar biosynthesis in commercial seaweed Gracilariopsis lemaneiformis, the activities of four enzymes participating in the agar biosynthesis were detected, and phosphoglucomutase (PGM) was confirmed as highly correlated with agar accumulation. Three genes of PGM (GlPGM1, GlPGM2 and GlPGM3) were identified from the G. lemaneiformis genome. The subcellular localization analysis validated that GlPGM1 was located in the chloroplast and GlPGM3 was not significantly distributed in the organelles. Both the GlPGM1 and GlPGM3 protein levels showed a remarkable consistency with the agar variations, and GlPGM3 may participate in the carbon flux between (iso)floridoside, floridean starch and agar synthesis. After treatment with the PGM inhibitor, the agar and floridean starch contents and the activities of floridean starch synthase were significantly decreased; products identified in the Calvin cycle, the pentose phosphate pathway, the Embden-Meyerhof-Parnas pathway and the tricarboxylic acid cycle were depressed; however, lipids, phenolic acids and the intermediate metabolites, fructose-1,6-phosphate were upregulated. These findings reveal the essential role of PGM in regulating the carbon flux between agar and other carbohydrates in G. lemaneiformis, providing a guide for the artificial regulation of agar accumulation. [ABSTRACT FROM AUTHOR]

Voice Processing Systems (VPSes), now widely deployed, have become deeply involved in people's daily lives, helping drive the car, unlock the smartphone, make online purchases, etc. Unfortunately, recent research has shown that those systems based on deep neural networks are vulnerable to adversarial examples, which attract significant attention to VPS security. This review presents a detailed introduction to the background knowledge of adversarial attacks, including the generation of adversarial examples, psychoacoustic models, and evaluation indicators. Then we provide a concise introduction to defense methods against adversarial attacks. Finally, we propose a systematic classification of adversarial attacks and defense methods, with which we hope to provide a better understanding of the classification and structure for beginners in this field. [ABSTRACT FROM AUTHOR]

Automated tongue segmentation is a critical component of tongue diagnosis, especially in Traditional Chinese Medicine (TCM), where it has been practiced for thousands of years and is generally considered pain-free and non-invasive. Therefore, a more precise, fast, and robust tongue segmentation system to automatically segment tongue images from its raw format is necessary. Previous algorithms segmented the tongue in different ways, where the results are either inaccurate or time-consuming. Furthermore, none of them developed a dedicated, automatic segmentation system. In this paper, we proposed TongueNet, which is a precise and fast automatic tongue segmentation system. U-net is utilized as the segmentation backbone applying a small-scale image dataset. Besides this, a morphological layer is proposed in the latter stages of the architecture. The proposed system when applied to a tongue image dataset with 1000 images, achieved the highest Pixel Accuracy of 98.45% and consumed 0.267 s per picture on average, which outperformed conventional state-of-the-art tongue segmentation methods in both accuracy and speed. Extensive qualitative and quantitative experiments showed the robustness of the proposed system concerning different positions, poses, and shapes. The results indicate a promising step in achieving a fully automated tongue diagnosis system. [ABSTRACT FROM AUTHOR]

Rice false smut is a worldwide devastating rice disease infected by the fungal pathogen Villosiclava virens. Ustiloxin A (UA) and ustiloxin B (UB), cyclopeptide mycotoxins, were the major ustiloxins isolated from the rice false smut balls (FSBs) that formed in the pathogen-infected rice spikelets. Based on the specific monoclonal antibodies (mAbs) 2D3G5 and 1B5A10, respectively, against UA and UB, the lateral flow immunoassays (LFIAs) were developed, and the indicator ranges for UA and UB both were 50-100 ng/mL. The cross-reactivities of UB for UA LFIA, and UA for UB LFIA were 5% and 20%, respectively, which were consistent with the icELISA results reported previously. Even at 50,000 ng/mL, none of other commonly existent metabolites in rice samples caused noticeable inhibition. The LFIAs were used for determination of UA and UB contents in rice FSBs and rice grains, and the results were agreeable with those by HPLC and icELISA. There was no change in the sensitivity of either dipstick stored at 4 °C) after at least three months. The developed LFIA has specificity and sensitivity for detecting UA and UB as well as simplicity to use. It will be a potential point-of-care device for rapid evaluation of the rice samples contaminated by UA and UB.