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To increase the imaging resolution and detection capability, the field strength of static magnetic fields (SMFs) in magnetic resonance imaging (MRI) has significantly increased in the past few decades. However, research on the side effects of high magnetic field is still very inadequate and the effects of SMF above 1 T (Tesla) on B cells have never been reported. Here, we show that 33.0 T ultra‐high SMF exposure causes immunosuppression and disrupts B cell differentiation and signaling. 33.0 T SMF treatment resulted in disturbance of B cell peripheral differentiation and antibody secretion and reduced the expression of IgM on B cell membrane, and these might be intensity dependent. In addition, mice exposed to 33.0 T SMF showed inhibition on early activation of B cells, including B cell spreading, B cell receptor clustering and signalosome recruitment, and depression of both positive and negative molecules in the proximal BCR signaling, as well as impaired actin reorganization. Sequencing and gene enrichment analysis showed that SMF stimulation also affects splenic B cells' transcriptome and metabolic pathways. Therefore, in the clinical application of MRI, we should consider the influence of SMF on the immune system and choose the optimal intensity for treatment. [ABSTRACT FROM AUTHOR]

Sweetpotato (Ipomoea batatas (L.) Lam.) is a globally significant storage root crop, but it is highly susceptible to yield reduction under severe drought conditions. Therefore, understanding the mechanism of sweetpotato resistance to drought stress is helpful for the creation of outstanding germplasm and the selection of varieties with strong drought resistance. In this study, we conducted a comprehensive analysis of the phenotypic and physiological traits of 17 sweetpotato breeding lines and 10 varieties under drought stress through a 48 h treatment in a Hoagland culture medium containing 20% PEG6000. The results showed that the relative water content (RWC) and vine-tip fresh-weight reduction (VTFWR) in XS161819 were 1.17 and 1.14 times higher than those for the recognized drought-resistant variety Chaoshu 1. We conducted RNA-seq analysis and weighted gene co-expression network analysis (WGCNA) on two genotypes, XS161819 and 18-12-3, which exhibited significant differences in drought resistance. The transcriptome analysis revealed that the hormone signaling pathway may play a crucial role in determining the drought resistance in sweetpotato. By applying WGCNA, we identified twenty-two differential expression modules, and the midnight blue module showed a strong positive correlation with drought resistance characteristics. Moreover, twenty candidate Hub genes were identified, including g47370 (AFP2), g14296 (CDKF), and g60091 (SPBC2A9), which are potentially involved in the regulation of drought resistance in sweetpotato. These findings provide important insights into the molecular mechanisms underlying drought resistance in sweetpotato and offer valuable genetic resources for the development of drought-resistant sweetpotato varieties in the future. [ABSTRACT FROM AUTHOR]

Idioms are a unique class of words in the Chinese language that can be challenging for Chinese machine reading comprehension due to their formal simplicity and the potential mismatch between their literal and figurative meanings. To address this issue, this paper adopted the "2 + 2" structure as the representation model for idiom structure feature extraction. According to the linguistic theory of idioms, to enhance the model's learning ability for idiom semantics, we propose a two-stage semantic expansion method that leverages semantic knowledge during the pre-training stage and extracts idiom interpretation information during the fine-tuning stage to improve the model's understanding of idioms. Moreover, with the consideration of the inferential interaction between global and local information during context fusion, which is neglected by all current works, we propose a method that utilizes a multi-headed attention mechanism to fully extract global and local information by selecting three attention patterns in the fine-tuning stage. This enables the fusion of semantic information extracted by the model at different granularities, leading to improved accuracy. The experimental results demonstrated that our proposed BERT-IDM model outperformed the baseline BERT model by achieving a 4.1% accuracy improvement. [ABSTRACT FROM AUTHOR]

Sweetpotato (Ipomoea batatas (L.) Lam.), which has a complex genome, is one of the most important storage root crops in the world. Sweetpotato blades are considered as a potential source of natural antioxidants owing to their high phenolic content with powerful free radical scavenging ability. The molecular mechanism of phenolic metabolism in sweetpotato blades has been seldom reported thus far. In this work, 23 sweetpotato genotypes were used for the analysis of their antioxidant activity, total polyphenol content (TPC) and total flavonoid content (TFC). 'Shangshu19' and 'Wan1314-6' were used for RNA-seq. The results showed that antioxidant activity, TPC and TFC of 23 genotypes had significant difference. There was a significant positive correlation between TPC, TFC and antioxidant activity. The RNA-seq analysis results of two genotypes, 'Shangshu19' and 'Wan1314-6', which had significant differences in antioxidant activity, TPC and TFC, showed that there were 7810 differentially expressed genes (DEGs) between the two genotypes. Phenylpropanoid biosynthesis was the main differential pathway, and upregulated genes were mainly annotated to chlorogenic acid, flavonoid and lignin biosynthesis pathways. Our results establish a theoretical and practical basis for sweetpotato breeding with antioxidant activity and phenolics in the blades and provide a theoretical basis for the study of phenolic metabolism engineering in sweetpotato blade. [ABSTRACT FROM AUTHOR]

In this paper, a novel miniaturized planar antipodal Vivaldi antenna (AVA) with high gain and back radiation reduction for 5G millimeter‐wave (mm‐Wave) communication is presented. First, due to the use of the gradual corrugated edges (GCE), the operating band of the antenna is extended in the direction of lower frequencies and the overall gain is also improved as well. Second, its gain of the antenna is better enhanced at the high frequency band through I‐Shape Metal Director (IMD). Lastly, to further reduce the back radiation, the split ring resonance branches (SRB) are added to the ground. The antenna front‐back ratio has improved considerably to over 20 dB. Meanwhile the antenna gain is improved further. Furthermore, a prototype antenna array was fabricated and the measurement results clearly show that the antenna array gain varies in the range of 15.86–16.43 dB when operating in the 5G millimeter wave band (24.75–28.35 GHz). [ABSTRACT FROM AUTHOR]

In the medical field, extracting medical entities from text by Named Entity Recognition (NER) has become one of the research hotspots. This thesis takes the chapter-level diabetes literature as the research object and uses a deep learning method to extract medical entities in the literature. Based on the deep and bidirectional transformer network structure, the pre-training language model BERT model can solve the problem of polysemous word representation, and supplement the features by large-scale unlabeled data, combined with BiLSTM-CRF model extracts of the long-distance features of sentences. On this basis, in view of the problem that the model cannot focus on the local information of the sentence, resulting in insufficient feature extraction, and considering the characteristics of Chinese data mainly in words, this thesis proposes a Named Entity Recognition method based on BIBC. This method combines Iterated Dilated CNN to enable the model to take into account global and local features at the same time, and uses the BERT-WWM model based on whole word masking to further extract semantic information from Chinese data. In the experiment of diabetic entity recognition in Ruijin Hospital, the accuracy rate, recall rate, and F1 score are improved to 79.58%, 80.21%, and 79.89%, which are better than the evaluation indexes of existing studies. It indicates that the method can extract the semantic information of diabetic text more accurately and obtain good entity recognition results, which can meet the requirements of practical applications. [ABSTRACT FROM AUTHOR]

To address the problem of poor semantic reasoning of models in multiple-choice Chinese machine reading comprehension (MRC), this paper proposes an MRC model incorporating multi-granularity semantic reasoning. In this work, we firstly encode articles, questions and candidates to extract global reasoning information; secondly, we use multiple convolution kernels of different sizes to convolve and maximize pooling of the BERT-encoded articles, questions and candidates to extract local semantic reasoning information of different granularities; we then fuse the global information with the local multi-granularity information and use it to make an answer selection. The proposed model can combine the learned multi-granularity semantic information for reasoning, solving the problem of poor semantic reasoning ability of the model, and thus can improve the reasoning ability of machine reading comprehension. The experiments show that the proposed model achieves better performance on the C 3 dataset than the benchmark model in semantic reasoning, which verifies the effectiveness of the proposed model in semantic reasoning. [ABSTRACT FROM AUTHOR]

In order to study the internal flow characteristics and external droplet velocity distribution characteristics of the swirl nozzle, the following methods were used: numerical simulations were used to study the internal flow characteristics of a swirl nozzle and phase Doppler particle velocimetry was used to determine the corresponding external droplet velocity distribution under medium and low pressure conditions. The distributions of pressure and water velocity inside the nozzle were obtained. Meanwhile, the velocities of droplets outside the nozzle in different sections were discussed. The results show that the flow rate in the swirl nozzle increases with the increase in inlet pressure, and the local pressure in the region decreases because of the excessive velocity at the internal outlet section of the swirl nozzle, resulting in cavitation. The experimental results show that under an external flow field, the minimum droplet velocity occurs in the axial direction; starting from the axis, the velocity first increases and then decreases along the radial direction. Swirling motion inside the nozzle and velocity variations in the external flow field occur under medium and low pressure conditions. The relationship between the inlet pressure and the distributions of water droplets' velocities was established, which provides a reference for the research and development of the swirl nozzle. [ABSTRACT FROM AUTHOR]

Luteolin, a plant-derived flavonoid, was found to exert effective inhibitory effect to peroxidase activity in a non-competitive manner with an IC 50 of (6.62 ± 0.45) × 10−5 mol L−1. The interaction between luteolin and peroxidase induced the formation of a static complex with a binding constant (K sv) of 7.31 × 103 L mol−1 s−1 driven by hydrogen bond and hydrophobic interaction. Further, the molecular interaction between luteolin and peroxidase resulted in intrinsic fluorescence quenching, structural and conformational alternations which were determined by multispectroscopic techniques combined with computational molecular docking. Molecular docking results revealed that luteolin bound to peroxidase and interacted with relevant amino acid residues in the hydrophobic pocket. These results will provide information for screening additional peroxidase inhibitors and provide evidence of luteolin's potential application in preservation and processing of fruit and vegetables and clinical disease remedy. • HRP activity was inhibited by luteolin in a non-competitive manner. • The thermosensitivity of HRP decreased after treating with luteolin. • The conformation of HRP changed after treating with luteolin. • The surface of structure sharply decreased with treatment of luteolin. [ABSTRACT FROM AUTHOR]

We report here a new cultivation system for sweetpotato [ Ipomoea batatas (L.) Lam.] production, named grafted overhead-sweetpotato cultivation (GOSC) system. In this system, sweetpotato (as scions) was grafted with convolvulaceae relatives (as stocks), and the stems of grafted sweetpotato were buried in a solid medium without any nutrient and hung in the air to regenerate overhead-sweetpotato (storage roots). The results showed that Ipomoea trifida (6×), Beinong5521 (5×) and SH-2 (6×) were the best stocks. All the tested sweetpotato cultivars could produce overhead-sweetpotato with different yields. The mixture of sand, perlite and vermiculite with a 1:1:1 (v/v/v) ratio was the best solid medium for the GOSC system. The key stage of overhead-sweetpotato formation was about 20 days to 55 days after stem buried. Since storage roots are not regenerated from stocks grown in fertilized soil but from scion stems buried in non-fertilized solid medium, it seemed that the grafted overhead-sweetpotato plants had root-function spatial division (RFSD), i.e. absorbing roots of stocks and storage roots of scions. The graft compatibility with sweetpotato, the stock without underground storage roots, and the stem-buried media without nutrient supply, are the key factors for RFSD and overhead-sweetpotato production. This system could be used as a model for the study of the interaction between stock and scion as well as the source-sink relationship in sweetpotato. [ABSTRACT FROM AUTHOR]

• gsm1 was isolated from an Arabidopsis glucose-hypersensitive mutant screen. • GSM1 encodes a putative RNA helicase and was localized to the nucleus. • gsm1 was sensitive not only to glucose but also to ABA. • GSM1 negatively regulates Glc-induced ABA signaling. In plants, sugar acts as an essential signaling molecule that modulates various aspects of metabolism, growth and development, which are also controlled by phytohormones. However, the molecular mechanism of cross-talk between sugar and phytohormones still remains to be elucidated. We have identified gsm1 (glucose-hypersensitive mutant 1) as a mutant with impaired cotyledon development that shows sensitivity to exogenous abscisic acid (ABA). The addition of fluridone can reverse the glucose (Glc) inhibitory effect in gsm1 , implying that endogenous ABA is involved in the Glc response of gsm1. In 4.5% Glc, the expression of Glc-induced ABA-responsive genes in gsm1-1 was nearly two times higher than that in the wild type. Compared to gsm1-1 , the gsm1-1 abi4-1 double mutant exhibited reduced sensitivity to Glc and ABA, which was similar to the Glc and ABA insensitive phenotype of abi4-1 , suggesting that ABI4 is epistatic to GSM1. In the treatment with 4.5% Glc, the GSM1 transcript level was greatly increased in abi4-1 by almost 4-fold of that in the wild type. These data suggest that GSM1 plays an important role in the ABI4-regulated Glc-ABA signaling cascade during Arabidopsis early seedling growth. [ABSTRACT FROM AUTHOR]

Background: The study of changes in the microbiome in chronic pancreatitis (CP) and pancreatic ductal adenocarcinoma (PDAC) holds significant potential for developing noninvasive diagnostic tools as well as innovative interventions to alter the progression of diseases. This systematic review and meta-analysis aimed to analyze in detail the taxonomic and functional characteristics of the gut microbiome in patients with CP and PDAC., Methods: Two researchers conducted a systematic search across public databases to gather all published research up to June 2023. Diversity and gut microbiota composition are the main outcomes we focus on., Results: This meta-analysis included 14 studies, involving a total of 1511 individuals in the PDAC (n=285), CP (n=342), and control (n=649) groups. Our results show a significant difference in the composition of gut microbiota between PDAC/CP patients compared to healthy controls (HC), as evidenced by a slight decrease in α-diversity, including Shannon (SMD=-0.33; P=0.002 and SMD=-0.59; P<0.001, respectively) and a statistically significant β-diversity (P<0.05). The pooled results showed that at the phylum level, the proportion of Firmicutes was lower in PDAC and CP patients than in HC patients. At the genus level, more than two studies demonstrated that 4 genera were significantly increased in PDAC patients compared to HC (e.g., Escherichia-Shigella and Veillonella). CP patients had an increase in 4 genera (e.g., Escherichia-Shigella and Klebsiella) and a decrease in 8 genera (e.g., Coprococcus and Bifidobacterium) compared to HC. Functional/metabolomics results from various studies also showed differences between PDAC/CP patients and HC. In addition, this study found no significant differences in gut microbiota between PDAC and CP patients., Conclusions: Current evidence suggests changes in gut microbiota is associated with PDAC/CP, commonly reflected by a reduction in beneficial species and an increase in the pathogenic species. Further studies are needed to confirm these findings and explore therapeutic possibilities., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Polycrystalline zinc selenide is widely used in advanced optical systems due to its superior optical properties. However, the soft and brittle properties bring a challenge for high-quality surface processing. In recent years, elliptical vibration cutting has been proven as a promising method for machining brittle materials. In the present research, a series of grooving and planning experiments were carried out to investigate the machinability of zinc selenide with elliptical vibration cutting. The removal mechanism was analyzed from fracture characteristics, chip morphology, and phase transformation. The results show that elliptical vibration cutting is effective in suppressing cleavage-induced craters. Reducing the nominal cutting speed is beneficial to inhibit the spring back-induced tearing of grains. A 94-time increase in the critical depth of cut was achieved by vibration trajectory optimization compared to ordinary cutting. Moreover, the influence mechanism of feed on the evolution of surface morphology was revealed. Finally, a zinc selenide microlens array was successfully fabricated. The performance was evaluated by geometric parameter measurements and a multiple imaging test. The findings provide a prospective method for ductile regime machining of zinc selenide.

Polyphenol oxidase is the enzyme responsible for enzymatic browning in sweetpotato that decreases the commercial value of sweetpotato products. Here we reported the cloning and characterization of a new cDNA encoding PPO from sweetpotato, designated as IbPPO (GeneBank accession number: AY822711). The full-length cDNA of IbPPO is 1984 bp with a 1767 bp open reading frame (ORF) encoding a 588 amino acid polypeptide with calculated molecular weight of 65.7 kDa and theoretical pI of 6.28. The coding sequence of IbPPO was also directly amplified from the genomic DNA of sweetpotato that demonstrated that IbPPO was an intron-free gene. The computational comparative analysis revealed that IbPPO showed homology to other PPOs of plant origin and contained a 50 amino acid plastidial transit peptides at its N-terminal and the two conserved CuA and CuB copper-binding motifs in the catalytic region of IbPPO. A highly conserved serine-rich motif was firstly found in the transit peptides of plant PPO enzymes. Then the homology-based structural modeling of IbPPO showed that IbPPO had the typical structure of PPO: the catalytic copper center was accommodated in a central four-helix bundle located in a hydrophobic pocket close to the surface. Finally, the results of the semi-quantitative RT-PCR analysis of IbPPO in different tissues demonstrated that IbPPO could express in all the organs of sweetpotato including: mature leaves, young leaves, the stems of mature leaves (petioles), the storage roots and the veins but at different levels. The highest-level expression of IbPPO was found in veins, followed by storage roots, young leaves and mature leaves; and the lowest-level expression of IbPPO was found in petioles. The present researches will facilitate the development of anti-brown sweetpotato by genetic engineering.