377 results on '"Yu, W."'
Search Results
2. Association between Time Spent on Smart Devices and Change in Refractive Error: A 1-Year Prospective Observational Study among Hong Kong Children and Adolescents.
- Author
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Do, Chi-wai, Chan, Lily Y. L., Tse, Andy C. Y., Cheung, Teris, So, Billy C. L., Tang, Wing Chun, Yu, W. Y., Chu, Geoffrey C. H., Szeto, Grace P. Y., Lee, Regina L. T., and Lee, Paul H.
- Published
- 2020
- Full Text
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3. A Review of the Establishment of Effective Conductive Pathways of Conductive Polymer Composites and Advances in Electromagnetic Shielding.
- Author
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Nan X, Zhang Y, Shen J, Liang R, Wang J, Jia L, Yang X, Yu W, and Zhang Z
- Abstract
The enhancement of the electromagnetic interference shielding efficiency (EMI SE) for conductive polymer composites (CPCs) has garnered increasing attention. The shielding performance is influenced by conductivity, which is dependent on the establishment of effective conductive pathways. In this review, Schelkunoff's theory on outlining the mechanism of electromagnetic interference shielding was briefly described. Based on the mechanism, factors that influenced the electrical percolation threshold of CPCs were presented and three main kinds of efficient methods were discussed for establishing conductive pathways. Furthermore, examples were explored that highlighted the critical importance of such conductive pathways in attaining optimal shielding performance. Finally, we outlined the prospects for the future direction for advancing CPCs towards a balance of enhanced EMI SE and cost-performance.
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- 2024
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4. R2R3 MYB Transcription Factor GhMYB201 Promotes Cotton Fiber Elongation via Cell Wall Loosening and Very-Long-Chain Fatty Acid Synthesis.
- Author
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Suo Q, Fang N, Zeng J, Yan F, Zhu X, Wang Y, Yu W, Chen J, Liang A, Li Y, Kong J, and Xiao Y
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- Cotton Fiber, Cell Wall metabolism, Cell Wall genetics, Transcription Factors genetics, Transcription Factors metabolism, Gene Expression Regulation, Plant, Gossypium genetics, Gossypium metabolism, Plant Proteins genetics, Plant Proteins metabolism, Fatty Acids metabolism, Fatty Acids biosynthesis
- Abstract
Cotton fiber is the leading natural textile material, and fiber elongation plays an essential role in the formation of cotton yield and quality. Although a number of components in the molecular network controlling cotton fiber elongation have been reported, a lot of players still need to be functionally dissected to understand the regulatory mechanism of fiber elongation comprehensively. In the present study, an R2R3-MYB transcription factor gene, GhMYB201 , was characterized and functionally verified via CRISPR/Cas9-mediated gene editing. GhMYB201 was homologous to Arabidopsis AtMYB60, and both coding genes ( GhMYB201At and GhMYB201Dt ) were preferentially expressed in elongating cotton fibers. Knocking-out of GhMYB201 significantly reduced the rate and duration of fiber elongation, resulting in shorter and coarser mature fibers. It was found that GhMYB201 could bind and activate the transcription of cell wall loosening genes ( GhRDLs ) and also β-ketoacyl-CoA synthase genes ( GhKCSs ) to enhance very-long-chain fatty acid (VLCFA) levels in elongating fibers. Taken together, our data demonstrated that the transcription factor GhMYB201s plays an essential role in promoting fiber elongation via activating genes related to cell wall loosening and VLCFA biosynthesis.
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- 2024
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5. RcTRP5 Transcription Factor Mediates the Molecular Mechanism of Lignin Biosynthesis Regulation in R. chrysanthum against UV-B Stress.
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Gong F, Yu W, Cao K, Xu H, and Zhou X
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- Stress, Physiological, Acetylation, Lignin biosynthesis, Lignin metabolism, Ultraviolet Rays, Gene Expression Regulation, Plant, Transcription Factors metabolism, Transcription Factors genetics, Plant Proteins genetics, Plant Proteins metabolism
- Abstract
UV-B stress destroys the photosynthetic system of Rhododendron chrysanthum Pall. ( R. chrysanthum ), as manifested by the decrease of photosynthetic efficiency and membrane fluidity, and also promotes the accumulation of lignin. The MYB (v-myb avian myeloblastosis viral oncogene homolog) family of transcription factors can be involved in the response to UV-B stress through the regulation of lignin biosynthesis. This study indicated that both the donor and recipient sides of the R. chrysanthum were significantly damaged based on physiological index measurements made using OJIP curves under UV-B stress. The analysis of bioinformatics data revealed that the RcTRP5 transcription factor exhibits upregulation of acetylation at the K68 site, directly regulating the biosynthesis of lignin. Additionally, there was upregulation of the K43 site and downregulation of the K83 site of the CAD enzyme, as well as upregulation of the K391 site of the PAL enzyme. Based on these findings, we conjectured that the RcTRP5 transcription factor facilitates acetylation modification of both enzymes, thereby indirectly influencing the biosynthesis of lignin. This study demonstrated that lignin accumulation can alleviate the damage caused by UV-B stress to R. chrysanthum , which provides relevant ideas for improving lignin content in plants, and also provides a reference for the study of the metabolic regulation mechanism of other secondary substances.
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- 2024
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6. Theoretical Study on Vibrationally Resolved Electronic Spectra of Chiral Nanographenes.
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Ma Y, Feng X, Yu W, and Shen C
- Abstract
Nanographenes are of increasing importance owing to their potential applications in the photoelectronic field. Meanwhile, recent studies have primarily focused on the pure electronic spectra of nanographenes, which have been found to be inadequate for describing the experimental spectra that contain vibronic progressions. In this study, we focused on the vibronic effect on the electronic transition of a range of chiral nanographenes, especially in the low-energy regions with distinct vibronic progressions, using theoretical calculations. All the calculations were performed at the PBE0-D3(BJ)/def2-TZVP level of theory, adopting both time-dependent and time-independent approaches with Franck-Condon approximation. The resulting calculated curves exhibited good alignment with the experimental data. Notably, for the nanographenes incorporating helicene units, owing to the increasing π -extension, the major vibronic modes in the vibrationally resolved spectra differed significantly from those of the primitive helicenes. This investigation suggests that calculations that account for the vibronic effect could have better reproducibility compared with calculations based solely on pure electronic transitions. We anticipate that this study could pave the way for further investigations into optical and chiroptical properties, with a deeper understanding of the vibronic effect, thereby providing theoretical explanations with higher precision on more sophisticated nanographenes.
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- 2024
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7. Research Advancements in Salt Tolerance of Cucurbitaceae: From Salt Response to Molecular Mechanisms.
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Chen C, Yu W, Xu X, Wang Y, Wang B, Xu S, Lan Q, and Wang Y
- Subjects
- Crops, Agricultural genetics, Cucurbitaceae genetics, Cucurbitaceae physiology, Cucurbitaceae metabolism, Salt Tolerance genetics, Gene Expression Regulation, Plant
- Abstract
Soil salinization severely limits the quality and productivity of economic crops, threatening global food security. Recent advancements have improved our understanding of how plants perceive, signal, and respond to salt stress. The discovery of the Salt Overly Sensitive (SOS) pathway has been crucial in revealing the molecular mechanisms behind plant salinity tolerance. Additionally, extensive research into various plant hormones, transcription factors, and signaling molecules has greatly enhanced our knowledge of plants' salinity tolerance mechanisms. Cucurbitaceae plants, cherished for their economic value as fruits and vegetables, display sensitivity to salt stress. Despite garnering some attention, research on the salinity tolerance of these plants remains somewhat scattered and disorganized. Consequently, this article offers a review centered on three aspects: the salt response of Cucurbitaceae under stress; physiological and biochemical responses to salt stress; and the current research status of their molecular mechanisms in economically significant crops, like cucumbers, watermelons, melon, and loofahs. Additionally, some measures to improve the salt tolerance of Cucurbitaceae crops are summarized. It aims to provide insights for the in-depth exploration of Cucurbitaceae's salt response mechanisms, uncovering the roles of salt-resistant genes and fostering the cultivation of novel varieties through molecular biology in the future.
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- 2024
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8. Structural Characterization and Biological Properties Analysis of Exopolysaccharides Produced by Weisella cibaria HDL-4.
- Author
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Zhou B, Wang C, Yang Y, Yu W, Bin X, Song G, and Du R
- Abstract
An exopolysaccharide (EPS)-producing strain, identified as Weissella cibaria HDL-4, was isolated from litchi. After separation and purification, the structure and properties of HDL-4 EPS were characterized. The molecular weight of HDL-4 EPS was determined to be 1.9 × 10⁶ Da, with glucose as its monosaccharide component. Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (NMR) analyses indicated that HDL-4 EPS was a D-glucan with α-(1→6) and α-(1→4) glycosidic bonds. X-ray diffraction (XRD) analysis revealed that HDL-4 EPS was amorphous. Scanning electron microscope (SEM) and atomic force microscope (AFM) observations showed that HDL-4 EPS possesses pores, irregular protrusions, and a smooth layered structure. Additionally, HDL-4 EPS demonstrated significant thermal stability, remaining stable below 288 °C. It exhibited a strong metal ion adsorption activity, emulsification activity, antioxidant activity, and water-retaining property. Therefore, HDL-4 EPS can be extensively utilized in the food and pharmaceutical industries as an additive and prebiotic.
- Published
- 2024
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9. Impact Localization in Complex Cylindrical Shell Structures Based on the Time-Reversal Virtual Focusing Triangulation Method.
- Author
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Huang X, Xu R, Yu W, and Wu S
- Abstract
In addressing the challenging issue of impact source localization for large-scale anisotropic stiffened compartmental cylindrical shell structures, this paper presents a novel impact localization method. The method is based on a time-reversal virtual focusing triangulation approach and does not rely on prior knowledge of the structure or specific measurements of wave velocity. By employing energy power filtering to select key sensors, wavelet packet decomposition is utilized to extract narrowband Lamb wave signals, which are then synthesized. Further enhancement of signal recognition is achieved through time-reversal amplification techniques. Experimental results demonstrate that under non-motorized operating conditions, this method achieves an average error of 0.89 m. Under motorized operating conditions, the average error is 1.12 m. Although the presence of background noise leads to an increase in error, the overall localization performance is superior to traditional triangulation methods. Additionally, selecting the top three sensors in terms of energy power ranking can more accurately record impact response.
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- 2024
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10. Temperature Compensation Method Based on Bilinear Interpolation for Downhole High-Temperature Pressure Sensors.
- Author
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Shu Y, Hua C, Zhao Z, Wang P, Zhang H, Yu W, and Yu H
- Abstract
Due to their high accuracy, excellent stability, minor size, and low cost, silicon piezoresistive pressure sensors are used to monitor downhole pressure under high-temperature, high-pressure conditions. However, due to silicon's temperature sensitivity, high and very varied downhole temperatures cause a significant bias in pressure measurement by the pressure sensor. The temperature coefficients differ from manufacturer to manufacturer and even vary from batch to batch within the same manufacturer. To ensure high accuracy and long-term stability for downhole pressure monitoring at high temperatures, this study proposes a temperature compensation method based on bilinear interpolation for piezoresistive pressure sensors under downhole high-temperature and high-pressure environments. A number of calibrations were performed with high-temperature co-calibration equipment to obtain the individual temperature characteristics of each sensor. Through the calibration, it was found that the output of the tested pressure measurement system is positively linear with pressure at the same temperatures and nearly negatively linear with temperature at the same pressures, which serves as the bias correction for the subsequent bilinear interpolation temperature compensation method. Based on this result, after least squares fitting and interpolating, a bilinear interpolation approach was introduced to compensate for temperature-induced pressure bias, which is easier to implement in a microcontroller (MCU). The test results show that the proposed method significantly improves the overall measurement accuracy of the tested sensor from 21.2% F.S. to 0.1% F.S. In addition, it reduces the MCU computational complexity of the compensation model, meeting the high accuracy demand for downhole pressure monitoring at high temperatures and pressures.
- Published
- 2024
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11. Boosting the Electrocatalytic Oxygen Reduction Activity of MnN 4 -Doped Graphene by Axial Halogen Ligand Modification.
- Author
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Wei S, Zhao R, Yu W, Li L, and Zhang M
- Abstract
Exploring highly active electrocatalysts as platinum (Pt) substitutes for the oxygen reduction reaction (ORR) remains a significant challenge. In this work, single Mn embedded nitrogen-doped graphene (MnN
4 ) with and without halogen ligands (F, Cl, Br, and I) modifying were systematically investigated by density functional theory (DFT) calculations. The calculated results indicated that these ligands can transform the dyz and dxz orbitals of Mn atom in MnN4 near the Fermi-level into dz2 orbital, and shift the d -band center away from the Fermi-level to reduce the adsorption capacity for reaction intermediates, thus enhancing the ORR catalytic activity of MnN4 . Notably, Br and I modified MnN4 respectively with the lowest overpotentials of 0.41 and 0.39 V, possess superior ORR catalytic activity. This work is helpful for comprehensively understanding the ligand modification mechanism of single-atom catalysts and develops highly active ORR electrocatalysts.- Published
- 2024
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12. Seismic Performance of a Single-Story Timber-Framed Masonry Structure Strengthened with Fiber-Reinforced Cement Mortar.
- Author
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Tan W, Zhou T, Zhu L, Zhao X, Yu W, Zhang L, and Liang Z
- Abstract
Timber-framed masonry structures are widely used around the world, and their seismic performance is generally poor. Most of them have not been seismically strengthened. In areas with high seismic fortification intensity, there are great potential safety hazards. And it is urgent to carry out effective seismic reinforcement. However, due to the complicated construction process of the existing reinforcement technology, the poor durability of the reinforcement materials, and the significant disturbance to the life of the original residents, an efficient single-story timber-framed masonry structure reinforcement technology suitable for comprehensive promotion and application has not been explored. In this paper, a fiber-reinforced cement mortar (FRCM) material was proposed. A 1/2 scale model of a single-story timber-framed masonry structure was taken as the research object. The method of strengthening a single-story timber-framed masonry structure with FRCM layer was adopted. And the shaking table test of the model before and after reinforcement was carried out in turn. The dynamic characteristics, failure modes, acceleration response and displacement response of the FRCM layer-strengthened structure were analyzed through comparisons of the two cases. The experimental results showed that the FRCM layer significantly improved the seismic performance of the seismic-damaged single-story timber-framed masonry structures. The X- and Y-direction natural frequencies of the model structure were increased by 31.30% and 30.22%, respectively, after the structure was strengthened with FRCM. During a rare eight-degree earthquake, the inter-story displacement angles in the X- and Y-direction of the unreinforced model reached 1/98 and 1/577, respectively, and the structure was destroyed, while the inter-story displacement angle of the FRCM-reinforced model was only 1/2 of that the unreinforced model. During a rare nine-degree earthquake, the X-direction inter-story displacement angle of the model strengthened with FRCM reached 1/78 and the Y-direction inter-story displacement angle reached 1/178. At this time, the reinforced model structure was destroyed, but there was no collapse of the structural components, which met the seismic design objectives of "operational under the design minor seismic intensity, repairable damage under the design seismic precautionary intensity, and collapse prevention under the design rare seismic intensity", which proved that the FRCM layer was an effective and feasible way to strengthen the existing single-story wood-masonry rural building.
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- 2024
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13. High-Value and Environmentally Friendly Recycling Method for Coal-Based Solid Waste Based on Polyurethane Composite Materials.
- Author
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Li X, Liu Y, Li M, Zhang S, Jia L, Zhu F, and Yu W
- Abstract
This study aims to provide a high-value and environmentally friendly method for the application of coal-based solid waste. Modified fly ash/polyurethane (MFA/PU) and modified coal gangue powder/polyurethane (MCG/PU) composites were prepared by adding different contents of MFA and MCG (10%, 20%, 30%, 40%). At the filler content of 30%, the compressive strengths of MFA/PU and MCG/PU are 84.1 MPa and 46.3 MPa, respectively, likely due to an improvement in interface compatibility, as indicated by scanning electron microscopy (SEM). The MFA/PU and MCG/PU composites present their highest limiting oxygen index (LOI) values of 29% and 23.5%, respectively, when their filler content is 30%. MFA has advantages in improving the LOIs of composites. Cone calorimetry (CCT) and SEM demonstrate that the two composites exhibit similar condensed-phase flame-retardant behaviors during combustion, which releases CO
2 in advance and accelerates the formation of a dense barrier layer. Compared with the MFA/PU composites, the MCG/PU composites could produce a more stable and dense barrier structure. Water quality tests show that heavy metals do not leak from FA and CG embedded in PU. This work provided a new strategy for the safe and high-value recycling of coal-based solid waste.- Published
- 2024
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14. Mechanism of Histone Arginine Methylation Dynamic Change in Cellular Stress.
- Author
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Ren XG, Li W, Li WX, and Yu W
- Subjects
- Methylation, Humans, DNA Damage, Acetylation, Protein Processing, Post-Translational, Stress, Physiological genetics, Histones metabolism, Arginine metabolism, Histone Deacetylase 1 metabolism, Histone Deacetylase 1 genetics
- Abstract
Histone arginine residue methylation is crucial for individual development and gene regulation. However, the dynamics of histone arginine methylation in response to cellular stress remains largely unexplored. In addition, the interplay and regulatory mechanisms between this and other histone modifications are important scientific questions that require further investigation. This study aimed to investigate the changes in histone arginine methylation in response to DNA damage. We report a global decrease in histone H3R26 symmetric dimethylation (H3R26me2s) and hypoacetylation at the H3K27 site in response to DNA damage. Notably, H3R26me2s exhibits a distribution pattern similar to that of H3K27ac across the genome, both of which are antagonistic to H3K27me3. Additionally, histone deacetylase 1 (HDAC1) may be recruited to the H3R26me2s demethylation region to mediate H3K27 deacetylation. These findings suggest crosstalk between H3R26me2s and H3K27ac in regulating gene expression.
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- 2024
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15. Feature Extraction Methods for Underwater Acoustic Target Recognition of Divers.
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Sun Y, Chen W, Shuai C, Zhang Z, Wang P, Cheng G, and Yu W
- Abstract
The extraction of typical features of underwater target signals and excellent recognition algorithms are the keys to achieving underwater acoustic target recognition of divers. This paper proposes a feature extraction method for diver signals: frequency-domain multi-sub-band energy (FMSE), aiming to achieve accurate recognition of diver underwater acoustic targets by passive sonar. The impact of the presence or absence of targets, different numbers of targets, different signal-to-noise ratios, and different detection distances on this method was studied based on experimental data under different conditions, such as water pools and lakes. It was found that the FMSE method has the best robustness and performance compared with two other signal feature extraction methods: mel frequency cepstral coefficient filtering and gammatone frequency cepstral coefficient filtering. Combined with the commonly used recognition algorithm of support vector machines, the FMSE method can achieve a comprehensive recognition accuracy of over 94% for frogman underwater acoustic targets. This indicates that the FMSE method is suitable for underwater acoustic recognition of diver targets.
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- 2024
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16. Unified Solid Solution Product of [Nb][C] in Nb-Microalloyed Steels with Various Carbon Contents.
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Yan Y, Xue Y, Liu K, Yu W, Shi J, and Wang M
- Abstract
In this work, the solid solution product of [Nb][C] in the Nb-microalloyed steels with various carbon contents in the range of 0.20~1.80 wt.% was investigated by means of the extraction phase analysis method. The results showed that the Nb content in austenite tended to first decrease and then increase with the increase of carbon content in the steels. A unified solid solution product of [Nb][C] in austenite at different temperatures was obtained according to the results of the experimental steels. The Nb content in austenite of the experimental steels with high carbon contents was lower than that calculated by Ohtani's equation. The existence of NbC precipitates in the case and the core of the specimens carburized at 930 °C and 980 °C were verified by transmission electron microscopy (TEM) observations. The pinning effect of NbC precipitates on austenite grain growth was calculated according to the size and amount of NbC precipitates in the carburized case and the core of the carburized specimens. The calculated results of prior austenite grain sizes were in good agreement with the experimental results, which indicated that the unified solid solution product of [Nb][C] in Nb-microalloyed steels with various carbon contents was applicable for the low-pressure carburizing process.
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- 2024
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17. Microstructures and Rheological Properties of Short-Side-Chain Perfluorosulfonic Acid in Water/2-Propanol.
- Author
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Qiu Y, Zhao X, Li H, Liu S, and Yu W
- Abstract
The viscosity and viscoelasticity of polyelectrolyte solutions with a single electrostatic interaction have been carefully studied experimentally and theoretically. Despite some theoretical models describe experimental results well, the influence of multiple interactions (electrostatic and hydrophobic) on rheological scaling is not yet fully resolved. Herein, we systematically study the microstructures and rheological properties of short-side-chain perfluorosulfonic acid (S-PFSA), the most promising candidate of a proton exchange membrane composed of a hydrophobic backbone with hydrophilic side-chains, in water/2-propanol. Small-angle X-ray scattering confirms that semiflexible S-PFSA colloidal particles with a length of ~38 nm and a diameter of 1-1.3 nm are formed, and the concentration dependence of the correlation length (ξ) obeys the power law ξ~c
-0.5 consistent with the prediction of Dobrynin et al. By combining macrorheology with diffusing wave spectroscopy microrheology, the semidilute unentangled, semidilute entangled, and concentrated regimes corresponding to the scaling relationships ηsp ~c0.5 , ηsp ~c1.5 , and ηsp ~c4.1 are determined. The linear viscoelasticity indicates that the entanglement concentration (ce ) obtained from the dependence of ηsp on the polymer concentration is underestimated owing to hydrophobic interaction. The true entanglement concentration (cte ) is obtained by extrapolating the plateau modulus (Ge ) to the terminal modulus (Gt ). Furthermore, Ge and the plateau width, τr /τe (τr and τe denote reptation time and Rouse time), scale as Ge ~c2.4 and τr /τe ~c4.2 , suggesting that S-PFSA dispersions behave like neutral polymer solutions in the concentrated regime. This work provides mechanistic insight into the rheological behavior of an S-PFSA dispersion, enabling quantitative control over the flow properties in the process of solution coating.- Published
- 2024
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18. Enhanced High-Performance iPP/TPU/MWCNT Nanocomposite for Electromagnetic Interference Shielding.
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Li Y, Yu W, Ruan Q, Li K, Guo X, Bai Z, and Chen J
- Abstract
The rapid development of electronic communication technology has led to an undeniable issue of electromagnetic pollution, prompting widespread attention from researchers to the study of electromagnetic shielding materials. Herein, a simple and feasible method of melt blending was applied to prepare iPP/TPU/MWCNT nanocomposites with excellent electromagnetic shielding performance. The addition of maleic anhydride-grafted polypropylene (PP-g-MAH) effectively improved the interface compatibility of iPP and TPU. A double continuous structure within the matrix was achieved by controlling the iPP/TPU ratio at 4:6, while the incorporation of multi-walled carbon nanotubes endowed the composites with improved electromagnetic shielding properties. Furthermore, by regulating the addition sequence of raw materials during the melt-blending process, a selective distribution of carbon nanotubes in the TPU matrix was achieved, thereby constructing interconnected conductive networks within the composites, significantly enhancing the electromagnetic shielding performance of iPP/TPU/MWCNTs, which achieved a maximum EMI shielding efficiency of 37.8 dB at an iPP/TPU ratio of 4:6 and an MWCNT concentration of 10 wt.%.
- Published
- 2024
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19. Application of Diffusion Kurtosis Imaging and Blood Oxygen Level-Dependent Magnetic Resonance Imaging in Kidney Injury Associated with ANCA-Associated Vasculitis.
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Yu W, Yan W, Yi J, Cheng L, Luo P, Sun J, Gou S, and Fu P
- Subjects
- Humans, Male, Female, Middle Aged, Aged, Kidney diagnostic imaging, Kidney pathology, Magnetic Resonance Imaging methods, Adult, Diffusion Magnetic Resonance Imaging methods, Case-Control Studies, Glomerular Filtration Rate, Diffusion Tensor Imaging methods, Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis diagnostic imaging, Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis complications, Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis blood, Oxygen blood
- Abstract
Objective: Functional magnetic resonance imaging (fMRI) has been applied to assess the microstructure of the kidney. However, it is not clear whether fMRI could be used in the field of kidney injury in patients with Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV)., Methods: This study included 20 patients with AAV. Diffusion kurtosis imaging (DKI) and blood oxygen level-dependent (BOLD) scanning of the kidneys were performed in AAV patients and healthy controls. The mean kurtosis (MK), mean diffusivity (MD), and fractional anisotropy (FA) parameters of DKI, the R2* parameter of BOLD, and clinical data were further analyzed., Results: In AAV patients, the cortex exhibited lower MD but higher R2* values compared to the healthy controls. Medullary MK values were elevated in AAV patients. Renal medullary MK values showed a positive correlation with serum creatinine levels and negative correlations with hemoglobin levels and estimated glomerular filtration rate. To assess renal injury in AAV patients, AUC values for MK, MD, FA, and R2* in the cortex were 0.66, 0.67, 0.57, and 0.55, respectively, and those in the medulla were 0.81, 0.77, 0.61, and 0.53, respectively., Conclusions: Significant differences in DKI and BOLD MRI parameters were observed between AAV patients with kidney injuries and the healthy controls. The medullary MK value in DKI may be a noninvasive marker for assessing the severity of kidney injury in AAV patients.
- Published
- 2024
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20. Lumbrokinase Extracted from Earthworms Synergizes with Bevacizumab and Chemotherapeutics in Treating Non-Small Cell Lung Cancer by Targeted Inactivation of BPTF/VEGF and NF-κB/COX-2 Signaling.
- Author
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Hua C, Guo Z, Dai M, Zhou J, Ge H, Xue G, Xu F, Ru L, Lv K, Zhang G, Zheng L, Wang M, Teng Y, Yu W, and Guo W
- Subjects
- Animals, Humans, Mice, Cell Proliferation drug effects, Cell Line, Tumor, Mice, Nude, Xenograft Model Antitumor Assays, Antineoplastic Agents pharmacology, Apoptosis drug effects, Antineoplastic Combined Chemotherapy Protocols pharmacology, Endopeptidases, Bevacizumab pharmacology, Bevacizumab therapeutic use, Carcinoma, Non-Small-Cell Lung drug therapy, Carcinoma, Non-Small-Cell Lung pathology, Carcinoma, Non-Small-Cell Lung metabolism, Oligochaeta, NF-kappa B metabolism, Lung Neoplasms drug therapy, Lung Neoplasms pathology, Lung Neoplasms metabolism, Cyclooxygenase 2 metabolism, Cyclooxygenase 2 genetics, Vascular Endothelial Growth Factor A metabolism, Vascular Endothelial Growth Factor A genetics, Signal Transduction drug effects, Drug Synergism
- Abstract
As a kind of proteolytic enzyme extracted from earthworms , lumbrokinase has been used as an antithrombotic drug clinically. Nevertheless, its potential in anti-cancer, especially in anti-non-small cell lung cancer (NSCLC), as a single form of treatment or in combination with other therapies, is still poorly understood. In this study, we explored the anti-tumor role and the responsive molecular mechanisms of lumbrokinase in suppressing tumor angiogenesis and chemoresistance development in NSCLC and its clinical potential in combination with bevacizumab and chemotherapeutics. Lumbrokinase was found to inhibit cell proliferation in a concentration-dependent manner and caused metastasis suppression and apoptosis induction to varying degrees in NSCLC cells. Lumbrokinase enhanced the anti-angiogenesis efficiency of bevacizumab by down-regulating BPTF expression, decreasing its anchoring at the VEGF promoter region and subsequent VEGF expression and secretion. Furthermore, lumbrokinase treatment reduced IC50 values of chemotherapeutics and improved their cytotoxicity in parental and chemo-resistant NSCLC cells via inactivating the NF-κB pathway, inhibiting the expression of COX-2 and subsequent secretion of PGE2. LPS-induced NF-κB activation reversed its inhibition on NSCLC cell proliferation and its synergy with chemotherapeutic cytotoxicity, while COX-2 inhibitor celecoxib treatment boosted such effects. Lumbrokinase combined with bevacizumab, paclitaxel, or vincristine inhibited the xenograft growth of NSCLC cells in mice more significantly than a single treatment. In conclusion, lumbrokinase inhibited NSCLC survival and sensitized NSCLC cells to bevacizumab or chemotherapeutics treatment by targeted down-regulation of BPTF/VEGF signaling and inactivation of NF-κB/COX-2 signaling, respectively. The combinational applications of lumbrokinase with bevacizumab or chemotherapeutics are expected to be developed as promising candidate therapeutic strategies to improve the efficacy of the original monotherapy in anti-NSCLC.
- Published
- 2024
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21. The Rhododendron Chrysanthum Pall.s' Acetylation Modification of Rubisco Enzymes Controls Carbon Cycling to Withstand UV-B Stress.
- Author
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Liu M, Gong F, Yu W, Cao K, Xu H, and Zhou X
- Subjects
- Acetylation, Stress, Physiological, Plant Proteins metabolism, Plant Proteins genetics, Proteomics, Gene Expression Regulation, Plant, Chlorophyll metabolism, Lysine metabolism, Ultraviolet Rays, Photosynthesis, Carbon Cycle, Rhododendron metabolism, Rhododendron genetics, Ribulose-Bisphosphate Carboxylase metabolism
- Abstract
Lysine acetylation of proteins plays a critical regulatory function in plants. A few advances have been made in the study of plant acetylproteome. However, until now, there have been few data on Rhododendron chrysanthum Pall. ( R. chrysanthum ). We analyzed the molecular mechanisms of photosynthesis and stress resistance in R. chrysanthum under UV-B stress. We measured chlorophyll fluorescence parameters of R. chrysanthum under UV-B stress and performed a multi-omics analysis. Based on the determination of chlorophyll fluorescence parameters, R. chrysanthum Y(NO) (Quantum yield of non-photochemical quenching) increased under UV-B stress, indicating that the plant was damaged and photosynthesis decreased. In the analysis of acetylated proteomics data, acetylated proteins were found to be involved in a variety of biological processes. Notably, acetylated proteins were significantly enriched in the pathways of photosynthesis and carbon fixation, suggesting that lysine acetylation modifications have an important role in these activities. Our findings suggest that R. chrysanthum has decreased photosynthesis and impaired photosystems under UV-B stress, but NPQ shows that plants are resistant to UV-B. Acetylation proteomics revealed that up- or down-regulation of acetylation modification levels alters protein expression. Acetylation modification of key enzymes of the Calvin cycle (Rubisco, GAPDH) regulates protein expression, making Rubisco and GAPDH proteins expressed as significantly different proteins, which in turn affects the carbon fixation capacity of R. chrysanthum . Thus, Rubisco and GAPDH are significantly differentially expressed after acetylation modification, which affects the carbon fixation capacity and thus makes the plant resistant to UV-B stress. Lysine acetylation modification affects biological processes by regulating the expression of key enzymes in photosynthesis and carbon fixation, making plants resistant to UV-B stress.
- Published
- 2024
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22. The Molecular Mechanisms of Cuproptosis and Small-Molecule Drug Design in Diabetes Mellitus.
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Pan Z, Huang L, Gan Y, Xia Y, and Yu W
- Subjects
- Humans, Animals, Small Molecule Libraries pharmacology, Small Molecule Libraries chemistry, Mitochondria metabolism, Mitochondria drug effects, Reactive Oxygen Species metabolism, Diabetes Mellitus drug therapy, Diabetes Mellitus metabolism, Copper chemistry, Copper metabolism, Homeostasis drug effects, Drug Design
- Abstract
In the field of human health research, the homeostasis of copper (Cu) is receiving increased attention due to its connection to pathological conditions, including diabetes mellitus (DM). Recent studies have demonstrated that proteins associated with Cu homeostasis, such as ATOX1, FDX1, ATP7A, ATPB, SLC31A1, p53, and UPS, also contribute to DM. Cuproptosis, characterized by Cu homeostasis dysregulation and Cu overload, has been found to cause the oligomerization of lipoylated proteins in mitochondria, loss of iron-sulfur protein, depletion of glutathione, production of reactive oxygen species, and cell death. Further research into how cuproptosis affects DM is essential to uncover its mechanism of action and identify effective interventions. In this article, we review the molecular mechanism of Cu homeostasis and the role of cuproptosis in the pathogenesis of DM. The study of small-molecule drugs that affect these proteins offers the possibility of moving from symptomatic treatment to treating the underlying causes of DM.
- Published
- 2024
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23. Comparative Analysis of the Biochemical Composition, Amino Acid, and Fatty Acid Contents of Diploid, Triploid, and Tetraploid Crassostrea gigas .
- Author
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Fu J, Zhang E, Yu W, Wang W, Sun Y, Dong L, Zhang Y, Sun G, Li Z, Luo Q, and Yang J
- Subjects
- Animals, Female, Male, Crassostrea genetics, Crassostrea metabolism, Amino Acids metabolism, Diploidy, Triploidy, Tetraploidy, Fatty Acids metabolism, Fatty Acids analysis
- Abstract
Tetraploid oysters are artificially produced oysters that do not exist in nature. The successful breeding of 100% triploid oysters resolved the difficulties of traditional drug-induced triploids, such as the presence of drug residues and a low triploid induction rate. However, little is known concerning the biochemical composition and nutrient contents of such tetraploids. Therefore, we investigated compositional differences among diploid, triploid, and tetraploid Crassostrea gigas as well as between males and females of diploids and tetraploids. The findings indicated that glycogen, EPA, ∑PUFA, and omega-3 contents were significantly higher in triploid oysters than in diploids or tetraploids; tetraploid oysters had a significantly higher protein content, C14:0, essential amino acid, and flavor-presenting amino acid contents than diploids or triploids. For both diploid and tetraploids, females had significantly higher levels of glutamate, methionine, and phenylalanine than males but lower levels of glycine and alanine. In addition, female oysters had significantly more EPA, DHA, omega-3, and total fatty acids, a result that may be due to the fact that gonadal development in male oysters requires more energy to sustain growth, consumes greater amounts of nutrients, and accumulates more proteins. With these results, important information is provided on the production of C. gigas , as well as on the basis and backing for the genetic breeding of oysters.
- Published
- 2024
- Full Text
- View/download PDF
24. Oncogenic Role of SATB2 In Vitro: Regulator of Pluripotency, Self-Renewal, and Epithelial-Mesenchymal Transition in Prostate Cancer.
- Author
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Yu W, Srivastava R, Srivastava S, Ma Y, Shankar S, and Srivastava RK
- Subjects
- Humans, Male, Cell Line, Tumor, Neoplastic Stem Cells metabolism, Neoplastic Stem Cells pathology, Gene Expression Regulation, Neoplastic, Cell Self Renewal, Cell Proliferation, Epithelial-Mesenchymal Transition genetics, Prostatic Neoplasms pathology, Prostatic Neoplasms metabolism, Prostatic Neoplasms genetics, Kruppel-Like Factor 4 metabolism, Matrix Attachment Region Binding Proteins metabolism, Matrix Attachment Region Binding Proteins genetics, Transcription Factors metabolism, Transcription Factors genetics
- Abstract
Special AT-rich sequence binding protein-2 (SATB2) is a nuclear matrix protein that binds to nuclear attachment regions and is involved in chromatin remodeling and transcription regulation. In stem cells, it regulates the expression of genes required for maintaining pluripotency and self-renewal and epithelial-mesenchymal transition (EMT). In this study, we examined the oncogenic role of SATB2 in prostate cancer and assessed whether overexpression of SATB2 in human normal prostate epithelial cells (PrECs) induces properties of cancer stem cells (CSCs). The results demonstrate that SATB2 is highly expressed in prostate cancer cell lines and CSCs, but not in PrECs. Overexpression of SATB2 in PrECs induces cellular transformation which was evident by the formation of colonies in soft agar and spheroids in suspension. Overexpression of SATB2 in PrECs also resulted in induction of stem cell markers (CD44 and CD133), pluripotency-maintaining transcription factors (cMYC, OCT4, SOX2, KLF4, and NANOG), CADHERIN switch, and EMT-related transcription factors. Chromatin immunoprecipitation assay demonstrated that SATB2 can directly bind to promoters of BCL-2, BSP, NANOG, MYC, XIAP, KLF4, and HOXA2, suggesting SATB2 is capable of directly regulating pluripotency/self-renewal, cell survival, and proliferation. Since prostate CSCs play a crucial role in cancer initiation, progression, and metastasis, we also examined the effects of SATB2 knockdown on stemness. SATB2 knockdown in prostate CSCs inhibited spheroid formation, cell viability, colony formation, cell motility, migration, and invasion compared to their scrambled control groups. SATB2 knockdown in CSCs also upregulated the expression of E-CADHERIN and inhibited the expression of N-CADHERIN, SNAIL, SLUG, and ZEB1. The expression of SATB2 was significantly higher in prostate adenocarcinoma compared to normal tissues. Overall, our data suggest that SATB2 acts as an oncogenic factor where it is capable of inducing malignant changes in PrECs by inducing CSC characteristics.
- Published
- 2024
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25. Genome-Wide Identification and Expression Analysis of the YTH Domain-Containing RNA-Binding Protein Family in Cinnamomum camphora .
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Zhang J, Yao S, Cheng X, Zhao Y, Yu W, Ren X, Ji K, and Yu Q
- Subjects
- Protein Domains, Genome, Plant, Gene Expression Profiling, Multigene Family, Cinnamomum camphora genetics, Cinnamomum camphora metabolism, RNA-Binding Proteins genetics, RNA-Binding Proteins metabolism, Gene Expression Regulation, Plant, Phylogeny, Plant Proteins genetics, Plant Proteins metabolism, Plant Proteins chemistry
- Abstract
N
6 -methyladenosine (m6 A) is one of the most abundant chemical modifications on mRNA in eukaryotes. RNA-binding proteins containing the YT521-B (YTH) domain play crucial roles in post-transcriptional regulation of plant growth, development, and stress response by reading the m6 A mark. However, the YTH domain-containing RNA-binding protein family has not been studied in a valuable and medicinal tree such as Cinnamomum camphora ( C. camphora ) yet. In this study, we identified 10 YTH genes in C. camphora , located on eight out of 12 chromosomes. Phylogenetic analysis revealed that these genes can be classified into two major classes, YTHDF ( CcDF ) and YTHDC ( CcDC ). Closely related CcYTHs within the same class exhibited a similar distribution of conserved motifs and domain organization, suggesting functional similarities among these closely related CcYTHs . All CcYTH proteins possessed a highly conserved YTH domain, with CcDC1A containing an additional CCCH domain. The liquid-liquid phase separation (LLPS) predictions indicate that CcDC1A , CcDF1A , CcDF1C , CcDF3C , CcDF4C , and CcDF5C may undergo phase transitions. Quantitative expression analysis revealed that tissue-specific expression was observed fo CcYTHs . Notably, there were two genes, CcDF1A and CcDF5C ; both exhibited significantly higher expression levels in various tissues than other genes, indicating that the m6 A-YTH regulatory network in C. camphora might be quite distinct from that in most plants such as Arabidopsis thaliana ( A. thaliana ) with only one abundant YTH protein. According to the analysis of the up-stream cis-regulatory elements of these YTH genes, these genes could be closely related to stress, hormones, and development. The following stress response experiments further verified that their expression levels indeed changed under both PEG and NaCl treatments. These findings not only provide a foundation for future functional analysis of CcYTHs in C. camphora , but also provide insights into the functions of epigenetic mark m6 A in forest trees.- Published
- 2024
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26. Role of Histone Modifications in Kidney Fibrosis.
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Pan S, Yuan T, Xia Y, Yu W, Zhou X, and Cheng F
- Subjects
- Humans, Kidney metabolism, Kidney physiopathology, Kidney pathology, Acetylation, Methylation, Protein Processing, Post-Translational, Histone Code, Fibrosis, Histones metabolism, Renal Insufficiency, Chronic metabolism, Renal Insufficiency, Chronic physiopathology
- Abstract
Chronic kidney disease (CKD) is characterized by persistent kidney dysfunction, ultimately resulting in end-stage renal disease (ESRD). Renal fibrosis is a crucial pathological feature of CKD and ESRD. However, there is no effective treatment for this condition. Despite the complex molecular mechanisms involved in renal fibrosis, increasing evidence highlights the crucial role of histone modification in its regulation. The reversibility of histone modifications offers promising avenues for therapeutic strategies to block or reverse renal fibrosis. Therefore, a comprehensive understanding of the regulatory implications of histone modifications in fibrosis may provide novel insights into more effective and safer therapeutic approaches. This review highlights the regulatory mechanisms and recent advances in histone modifications in renal fibrosis, particularly histone methylation and histone acetylation. The aim is to explore the potential of histone modifications as targets for treating renal fibrosis.
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- 2024
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27. A "Pro-Asp-Thr" Amino Acid Repeat from Vibrio sp. QY108 Alginate Lyase Exhibits Alginate-Binding Capacity and Enhanced Soluble Expression and Thermostability.
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Fu Z, Zhang F, Wang H, Tang L, Yu W, and Han F
- Subjects
- Protein Binding, Catalytic Domain, Bacterial Proteins metabolism, Bacterial Proteins genetics, Bacterial Proteins chemistry, Solubility, Amino Acid Sequence, Temperature, Recombinant Proteins metabolism, Recombinant Proteins chemistry, Recombinant Proteins genetics, Polysaccharide-Lyases metabolism, Polysaccharide-Lyases genetics, Polysaccharide-Lyases chemistry, Vibrio enzymology, Vibrio genetics, Alginates metabolism, Alginates chemistry, Enzyme Stability
- Abstract
Alginate lyases cleave the 1,4-glycosidic bond of alginate by eliminating sugar molecules from its bond. While earlier reported alginate lyases were primarily single catalytic domains, research on multi-module alginate lyases has been lfiguimited. This study identified VsAly7A, a multi-module alginate lyase present in Vibrio sp. QY108, comprising a "Pro-Asp-Thr(PDT)" fragment and two PL-7 catalytic domains (CD I and CD II). The "PDT" fragment enhances the soluble expression level and increases the thermostability and binding affinity to the substrate. Moreover, CD I exhibited greater catalytic efficiency than CD II. The incorporation of PDT-CD I resulted in an increase in the optimal temperature of VsAly7A, whereas CD II displayed a preference for polyG degradation. The multi-domain structure of VsAly7A provides a new idea for the rational design of alginate lyase, whilst the "PDT" fragment may serve as a fusion tag in the soluble expression of recombinant proteins.
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- 2024
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28. CD169 + Skin Macrophages Function as a Specialized Subpopulation in Promoting Psoriasis-like Skin Disease in Mice.
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Li M, Yu W, Liu Z, and Liu S
- Subjects
- Animals, Mice, Cytokines metabolism, Disease Models, Animal, Th17 Cells immunology, Th17 Cells metabolism, Cell Differentiation, Mice, Inbred C57BL, Psoriasis immunology, Psoriasis metabolism, Psoriasis pathology, Psoriasis chemically induced, Psoriasis genetics, Macrophages metabolism, Macrophages immunology, Skin metabolism, Skin pathology, Skin immunology, Sialic Acid Binding Ig-like Lectin 1 metabolism, Imiquimod
- Abstract
Skin macrophages are critical to maintain and restore skin homeostasis. They serve as major producers of cytokines and chemokines in the skin, participating in diverse biological processes such as wound healing and psoriasis. The heterogeneity and functional diversity of macrophage subpopulations endow them with multifaceted roles in psoriasis development. A distinct subpopulation of skin macrophages, characterized by high expression of CD169, has been reported to exist in both mouse and human skin. However, its role in psoriasis remains unknown. Here, we report that CD169
+ macrophages exhibit increased abundance in imiquimod (IMQ) induced psoriasis-like skin lesions. Specific depletion of CD169+ macrophages in CD169-ditheria toxin receptor (CD169-DTR) mice inhibits IMQ-induced psoriasis, resulting in milder symptoms, diminished proinflammatory cytokine levels and reduced proportion of Th17 cells within the skin lesions. Furthermore, transcriptomic analysis uncovers enhanced activity in CD169+ macrophages when compared with CD169- macrophages, characterized by upregulated genes that are associated with cell activation and cell metabolism. Mechanistically, CD169+ macrophages isolated from IMQ-induced skin lesions produce more proinflammatory cytokines and exhibit enhanced ability to promote Th17 cell differentiation in vitro. Collectively, our findings highlight the crucial involvement of CD169+ macrophages in psoriasis development and offer novel insights into the heterogeneity of skin macrophages in the context of psoriasis.- Published
- 2024
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29. SIRT6 Inhibits Anoikis of Colorectal Cancer Cells by Down-Regulating NDRG1.
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Li F, Yu W, Zhou X, Hou J, Gao Y, Zhang J, and Gao X
- Subjects
- Humans, Cell Line, Tumor, Down-Regulation, Signal Transduction, Epigenesis, Genetic, Anoikis genetics, Colorectal Neoplasms metabolism, Colorectal Neoplasms genetics, Colorectal Neoplasms pathology, Sirtuins metabolism, Sirtuins genetics, Gene Expression Regulation, Neoplastic, Cell Cycle Proteins metabolism, Cell Cycle Proteins genetics, Intracellular Signaling Peptides and Proteins metabolism, Intracellular Signaling Peptides and Proteins genetics
- Abstract
Anoikis, a form of apoptosis resulting from the loss of cell-extracellular matrix interaction, is a significant barrier to cancer cell metastasis. However, the epigenetic regulation of this process remains to be explored. Here, we demonstrate that the histone deacetylase sirtuin 6 (SIRT6) plays a pivotal role in conferring anoikis resistance to colorectal cancer (CRC) cells. The protein level of SIRT6 is negatively correlated with anoikis in CRC cells. The overexpression of SIRT6 decreases while the knockdown of SIRT6 increases detachment-induced anoikis. Mechanistically, SIRT6 inhibits the transcription of N-myc downstream-regulated gene 1 ( NDRG1 ), a negative regulator of the AKT signaling pathway. We observed the up-regulation of SIRT6 in advanced-stage CRC samples. Together, our findings unveil a novel epigenetic program regulating the anoikis of CRC cells.
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- 2024
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30. Gas Chromatography-Mass Spectrometry Metabolites and Transcriptome Profiling Reveal Molecular Mechanisms and Differences in Terpene Biosynthesis in Two Torrya grandis Cultivars during Postharvest Ripening.
- Author
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Zhang Z, Gao L, Tao L, Wu T, Suo J, Hu Y, Yu W, Wu J, and Song L
- Subjects
- Transcriptome, Plant Proteins genetics, Plant Proteins metabolism, Odorants analysis, Terpenes metabolism, Gas Chromatography-Mass Spectrometry methods, Gene Expression Regulation, Plant, Gene Expression Profiling methods
- Abstract
Terpene aroma compounds are key quality attributes of postharvest Torreya grandis nuts, contributing to their commercial value. However, terpene biosynthesis and regulatory networks in different T. grandis cvs. are still poorly understood. Here, chief cvs. 'Xi Fei' and 'Xiangya Fei' were investigated for their differences in terpene biosynthesis and gene expression levels during postharvest ripening using headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) and transcriptomic datasets. A total of 28 and 22 aroma compounds were identified in 'Xi Fei' and 'Xiangya Fei', respectively. Interestingly, differences in aroma composition between the two cvs. were mostly attributed to D-limonene and α-pinene levels as key determinants in Torreya nuts' flavor. Further, transcriptome profiling, correlation analysis, and RT-qPCR annotated two novel genes, TgTPS1 in 'Xi Fei' and TgTPS2 in 'Xiangya Fei', involved in terpene biosynthesis. In addition, six transcription factors (TFs) with comparable expression patterns to TgTPS1 and four TFs to TgTPS2 were identified via correlation analysis of a volatile and transcriptome dataset to be involved in terpene biosynthesis. Our study provides novel insight into terpene biosynthesis and its regulation at the molecular level in T. grandis nut and presents a valuable reference for metabolic engineering and aroma improvement in this less explored nut.
- Published
- 2024
- Full Text
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31. Review on Phase Synchronization Methods for Spaceborne Multistatic Synthetic Aperture Radar.
- Author
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Lin Q, Li S, and Yu W
- Abstract
Multistatic synthetic aperture radar (SAR) is a special mode of SAR system. The radar transmitter and receiver are located on different satellites, which brings many advantages, such as flexible baseline configuration, diverse receiving modes, and more detailed ground object classification information. The multistatic SAR has been widely used in interferometry, moving target detection, three-dimensional imaging, and other fields. The frequency offset between different oscillators will cause a modulation phase error in the signal. Therefore, phase synchronization is one of the most critical problems to be addressed in distributed SAR systems. This article reviews phase synchronization techniques, which are mainly divided into two methods: synchronization by direct microwave link and synchronization by a data-based estimation algorithm. Furthermore, the future development of synchronization technology is anticipated.
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- 2024
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32. A Sparse Recovery Algorithm for Suppressing Multiple Linear Frequency Modulation Interference in the Synthetic Aperture Radar Image Domain.
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Tong G, Lu X, Yang J, Yu W, Gu H, and Su W
- Abstract
In synthetic aperture radar (SAR) signal processing, compared with the raw data of level-0, level-1 SAR images are more readily accessible and available in larger quantities. However, an amount of level-1 images are affected by radio frequency interference (RFI), which typically originates from Linear Frequency Modulation (LFM) signals emitted by ground-based radars. Existing research on interference suppression in level-1 data has primarily focused on two methods: transforming SAR images into simulated echo data for interference suppression, or focusing interference in the frequency domain and applying notching filters to reduce interference energy. However, these methods overlook the effective utilization of the interference parameters or are confined to suppressing only one type of LFM interference at a time. In certain SAR images, multiple types of LFM interference manifest bright radiation artifacts that exhibit varying lengths along the range direction while remaining constant in the azimuth direction. It is necessary to suppress multiple LFM interference on SAR images when original echo data are unavailable. This article proposes a joint sparse recovery algorithm for interference suppression in the SAR image domain. In the SAR image domain, two-dimensional LFM interference typically exhibits differences in parameters such as frequency modulation rate and pulse width in the range direction, while maintaining consistency in the azimuth direction. Based on this observation, this article constructs a series of focusing operators for LFM interference in SAR images. These operators enable the sparse representation of dispersed LFM interference. Subsequently, an optimization model is developed that can effectively suppress multi-LFM interference and reduce image loss with the assistance of a regularization term in the image domain. Simulation experiments conducted in various scenarios validate the superior performance of the proposed method.
- Published
- 2024
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33. Crashworthiness Study of Functional Gradient Lattice-Reinforced Thin-Walled Tubes under Impact Loading.
- Author
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Liu Z, Wang Y, Liang X, and Yu W
- Abstract
Creating lightweight and impact-resistant box structures has been an enduring pursuit among researchers. A new energy-absorbing structure consisting of a bionic gradient lattice-enhanced thin-walled tube is presented in this article. The gradient lattice and thin-walled tube were prepared using selective laser melting (SLM) and wire-cutting techniques, respectively. To analyze the effects of gradient pattern, mass ratio, diameter range and impact speed on structural crashworthiness, low-speed impact at 4 m/s and finite element simulation experiments were conducted. The study demonstrates that the design of inward radial gradient lattice-reinforced thin-walled tubes can effectively enhance structure's energy-absorption efficiency and provide a more stable mode of deformation. It also shows a 17.44% specific energy-absorption advantage over the uniformly lattice-reinforced thin-walled tubes, with no significant overall gain in peak crushing force. A complex scale evaluation method was used to determine the optimum structure and the structure type with the best crashworthiness was found to be a gradient lattice-filled tube with a thickness of 0.9 mm and a slope index of 10. The gradient lattice-reinforced thin-walled tube suggested in this investigation offers guidance for designing a more efficient thin-walled energy-absorption structure.
- Published
- 2024
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34. Molecular Mechanism of Exogenous ABA to Enhance UV-B Resistance in Rhododendron chrysanthum Pall. by Modulating Flavonoid Accumulation.
- Author
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Yu W, Gong F, Xu H, and Zhou X
- Subjects
- Chlorophyll metabolism, Ultraviolet Rays, Abscisic Acid metabolism, Abscisic Acid pharmacology, Flavonoids metabolism, Rhododendron metabolism, Rhododendron genetics, Gene Expression Regulation, Plant drug effects
- Abstract
With the depletion of the ozone layer, the intensity of ultraviolet B (UV-B) radiation reaching the Earth's surface increases, which in turn causes significant stress to plants and affects all aspects of plant growth and development. The aim of this study was to investigate the mechanism of response to UV-B radiation in the endemic species of Rhododendron chrysanthum Pall. ( R. chrysanthum ) in the Changbai Mountains and to study how exogenous ABA regulates the response of R. chrysanthum to UV-B stress. The results of chlorophyll fluorescence images and OJIP kinetic curves showed that UV-B radiation damaged the PSII photosystem of R. chrysanthum , and exogenous ABA could alleviate this damage to some extent. A total of 2148 metabolites were detected by metabolomics, of which flavonoids accounted for the highest number (487, or 22.67%). KEGG enrichment analysis of flavonoids that showed differential accumulation by UV-B radiation and exogenous ABA revealed that flavonoid biosynthesis and flavone and flavonol biosynthesis were significantly altered. GO analysis showed that most of the DEGs produced after UV-B radiation and exogenous ABA were distributed in the cellular process, cellular anatomical entity, and catalytic activity. Network analysis of key DFs and DEGs associated with flavonoid synthesis identified key flavonoids (isorhamnetin-3-O-gallate and dihydromyricetin) and genes (TRINITY_DN2213_c0_g1_i4-A1) that promote the resistance of R. chrysanthum to UV-B stress. In addition, multiple transcription factor families were found to be involved in the regulation of the flavonoid synthesis pathway under UV-B stress. Overall, R. chrysanthum actively responded to UV-B stress by regulating changes in flavonoids, especially flavones and flavonols, while exogenous ABA further enhanced its resistance to UV-B stress. The experimental results not only provide a new perspective for understanding the molecular mechanism of the response to UV-B stress in the R. chrysanthum , but also provide a valuable theoretical basis for future research and application in improving plant adversity tolerance.
- Published
- 2024
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35. Development and Evaluation of a Novel Antibacterial Wound Dressing: A Powder Preparation Based on Cross-Linked Pullulan with Polyhexamethylene Biguanide for Hydrogel-Transition in Advanced Wound Management and Infection Control.
- Author
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Su J, Yu W, Guo X, Wang C, Wang Q, Chen B, Hu Y, and Dai H
- Abstract
As antibiotic resistance increasingly undermines traditional infection management strategies, there is a critical demand for innovative wound care solutions that address these emerging challenges. This study introduces a novel antibacterial wound dressing based on Cross-Linked Pullulan (Pul) and Polyhexamethylene Biguanide (PHMB) for enhanced wound management and infection control. The dressing's adsorption rate reached 200% of its original weight within 30 min, exceeded 300% after 5 h, and exhibited significant non-Newtonian fluid properties. The dressings were able to release the loaded medication completely within 20 min; additionally, the dressing demonstrated significant antibacterial activity against a broad spectrum of bacteria. Significantly, the therapeutic effects of the Pul-PHMB/GP dressing were evaluated in a mouse model. Compared to untreated wounds, wounds treated with Pul-PHMB/GP exhibited a significant gelation process within 5 min post-treatment and showed a significant increase in wound healing rate within 12 days. This powder preparation overcomes the limitations associated with liquid and gel dressings, notably in storage and precise application, preventing the premature expansion or dissolution often caused by PHMB in high-humidity environments. The powder form can transform into a gel upon contact with wound exudate, ensuring accurate coverage of irregular wounds, such as those from burns or pressure sores, and offers excellent chemical and physical stability in a dry state, which facilitates storage and transport. This makes the dressing particularly suitable for emergency medical care and precision therapy, significantly improving the efficiency and adaptability of wound treatment and providing robust support for clinical treatments and emergency responses.
- Published
- 2024
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36. An Injectable, Self-Healing, Adhesive Multifunctional Hydrogel Promotes Bacteria-Infected Wound Healing.
- Author
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Zhang L, Wang Y, Yang M, Yu W, Zhao Z, and Liu Y
- Abstract
Bacterial infections have a serious impact on public health. It is urgent to develop antibacterial hydrogels with good biocompatibility to reduce the use of antibiotics. In this study, poly(lipoic acid-co-sodium lipoate)-phytic acid (P(LA-SL)-PA) hydrogels are prepared by a simple mixture of the natural small molecules lipoic acid (LA) and phytic acid (PA) in a mild and green reaction environment. The crosslinking network is constructed through the connection of covalent disulfide bonds as well as the hydrogen bonds, which endow the injectable and self-healing properties. The P(LA-SL)-PA hydrogels exhibit an adjustable compression modulus and adhesion. The in vitro agar plates assay indicates that the antibacterial rate of hydrogels against Escherichia coli and Staphylococcus aureus is close to 95%. In the rat-infected wound model, the P(LA-SL)-PA hydrogels adhere closely to the tissue and promote epithelialization and collagen deposition with a significant effect on wound healing. These results prove that the P(LA-SL)-PA hydrogels could act as effective wound dressings for promoting the healing of infected wounds.
- Published
- 2024
- Full Text
- View/download PDF
37. Visual SLAM for Unmanned Aerial Vehicles: Localization and Perception.
- Author
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Zhuang L, Zhong X, Xu L, Tian C, and Yu W
- Abstract
Localization and perception play an important role as the basis of autonomous Unmanned Aerial Vehicle (UAV) applications, providing the internal state of movements and the external understanding of environments. Simultaneous Localization And Mapping (SLAM), one of the critical techniques for localization and perception, is facing technical upgrading, due to the development of embedded hardware, multi-sensor technology, and artificial intelligence. This survey aims at the development of visual SLAM and the basis of UAV applications. The solutions to critical problems for visual SLAM are shown by reviewing state-of-the-art and newly presented algorithms, providing the research progression and direction in three essential aspects: real-time performance, texture-less environments, and dynamic environments. Visual-inertial fusion and learning-based enhancement are discussed for UAV localization and perception to illustrate their role in UAV applications. Subsequently, the trend of UAV localization and perception is shown. The algorithm components, camera configuration, and data processing methods are also introduced to give comprehensive preliminaries. In this paper, we provide coverage of visual SLAM and its related technologies over the past decade, with a specific focus on their applications in autonomous UAV applications. We summarize the current research, reveal potential problems, and outline future trends from academic and engineering perspectives.
- Published
- 2024
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38. Experimental and Numerical Investigation of Dynamic Damage and Load Transfer of PBX Substitute Material under Low Velocity Impact.
- Author
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Xiao Y, Fu Q, Yu W, Fan C, Zou Y, and Sun Y
- Abstract
The accidental initiation of explosives under mechanical loads has caused numerous catastrophic events. Therefore, the dynamic damage behavior of confined polymer-bonded explosives (PBXs) must be assessed to improve their practical applicability. In this study, polymer-bonded sugar (PBS) materials were prepared using a novel agglomerate to develop a PBX substitute material with enhanced experimental safety. The mechanical properties of the PBS shell were evaluated using a dynamic compression test, which revealed that the compression response of the shell was affected by the strain rate. A low-velocity impact experiment was performed to investigate the dynamic damage and load transfer characteristics of the PBX substitute. A constitutive model was developed to characterize the mechanical response of PBS subjected to high strain rates, and implementing this model in ABAQUS ensured successful prediction of the damage evolution process associated with PBS. Simulation results indicated that the PBS specimen was primarily damaged around its center while sliding friction was dominant near the center during pressure application. Notably, different stress states result in distinct crack growth velocity histories along the axial direction, with the damage ratio progressively decreasing toward regions closer to the impact surface.
- Published
- 2024
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39. The Impurity Removal and Comprehensive Utilization of Phosphogypsum: A Review.
- Author
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Guan Q, Wang Z, Zhou F, Yu W, Yin Z, Zhang Z, Chi R, and Zhou J
- Abstract
Phosphogypsum (PG), a byproduct during the phosphoric acid production process, also known as the wet process, contains complex and diverse impurities, resulting in low utilization and considerable accumulation. This leads to a massive waste of land resources and a series of environmental pollution problems. Given the current urgent ecological and environmental situation, developing impurity removal processes with low energy consumption and high efficiency, exploring valuable resource recovery, preparing high value-added PG products, and broadening the comprehensive utilization ways of PG are significant strategies to promote the sustainable consumption of PG and sustainable development of the phosphorus chemical industry. This review comprehensively summarizes the advantages and disadvantages of existing PG impurity removal and utilization technologies and probes into the future development direction, which provides references and ideas for subsequent PG research.
- Published
- 2024
- Full Text
- View/download PDF
40. FDM 3D Printing and Properties of PBAT/PLA Blends.
- Author
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Yu W, Li M, Lei W, and Chen Y
- Abstract
Biodegradable polylactic acid (PLA) has been widely used in fused deposition modeling (FDM) 3D printing. In order to improve its comprehensive properties in 3D printing, in this study, 0-40% content of polybutylene adipate terephthalate(PBAT) was selected to be blended with PLA in a twin-screw extruder; the resulting pellets were drawn into a homogeneous filament; then, PBAT/PLA samples were prepared by FDM 3D printing, and the effects of the dosage of PBAT on the mechanical properties, thermal behavior, surface wettability and melt flowability of the samples were investigated. The results showed that all the samples could be printed smoothly, and the ductility was slightly improved by the increase in the PBAT dosage; the thermal stability of PLA was enhanced by blending with PBAT, and the crystallinity increased monotonically with the increase in PBAT. After blending with PBAT, the surfaces of the samples were more hydrophilic and flowable. The important conclusion achieved in this work was that the PBAT/PLA blends, especially those containing 30%PBAT, showed great potential to replace petroleum-based plastics and are suitable for use in FDM 3D printing technologies for different applications.
- Published
- 2024
- Full Text
- View/download PDF
41. Genome-Wide Characterization and Functional Validation of the ACS Gene Family in the Chestnut Reveals Its Regulatory Role in Ovule Development.
- Author
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Cui Y, Ji X, Yu W, Liu Y, Bai Q, and Su S
- Subjects
- Multigene Family, Genome, Plant, Phylogeny, Solanum lycopersicum genetics, Solanum lycopersicum growth & development, Solanum lycopersicum metabolism, Ovule genetics, Ovule growth & development, Ovule metabolism, Gene Expression Regulation, Plant, Plant Proteins genetics, Plant Proteins metabolism, Fagaceae genetics, Fagaceae growth & development, Fagaceae metabolism
- Abstract
Ovule abortion significantly contributes to a reduction in chestnut yield. Therefore, an examination of the mechanisms underlying ovule abortion is crucial for increasing chestnut yield. In our previous study, we conducted a comprehensive multiomic analysis of fertile and abortive ovules and found that ACS genes in chestnuts ( CmACS ) play a crucial role in ovule development. Therefore, to further study the function of ACS genes, a total of seven CmACS members were identified, their gene structures, conserved structural domains, evolutionary trees, chromosomal localization, and promoter cis-acting elements were analyzed, and their subcellular localization was predicted and verified. The spatiotemporal specificity of the expression of the seven CmACS genes was confirmed via qRT-PCR analysis. Notably, CmACS7 was exclusively expressed in the floral organs, and its expression peaked during fertilization and decreased after fertilization. The ACC levels remained consistently greater in fertile ovules than in abortive ovules. The ACSase activity of CmACS7 was identified using the genetic transformation of chestnut healing tissue. Micro Solanum lycopersicum plants overexpressing CmACS7 had a significantly greater rate of seed failure than did wild-type plants. Our results suggest that ovule fertilization activates CmACS7 and increases ACC levels, whereas an overexpression of CmACS7 leads to an increase in ACC content in the ovule prior to fertilization, which can lead to abortion. In conclusion, the present study demonstrated that chestnut ovule abortion is caused by poor fertilization and not by nutritional competition. Optimization of the pollination and fertilization of female flowers is essential for increasing chestnut yield and reducing ovule abortion.
- Published
- 2024
- Full Text
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42. Comparative Metabolomics and Transcriptome Studies of Two Forms of Rhododendron chrysanthum Pall. under UV-B Stress.
- Author
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Yu W, Gong F, Zhou X, Xu H, Lyu J, and Zhou X
- Abstract
Rhododendron chrysanthum Pall. ( R. chrysanthum ), a plant with UV-B resistance mechanisms that can adapt to alpine environments, has gained attention as an important plant resource with the ability to cope with UV-B stress. In this experiment, R. chrysanthums derived from the same origin were migrated to different culture environments (artificial climate chamber and intelligent artificial incubator) to obtain two forms of R. chrysanthum . After UV-B irradiation, 404 metabolites and 93,034 unigenes were detected. Twenty-six of these different metabolites were classified as UV-B-responsive metabolites. Glyceric acid is used as a potential UV-B stress biomarker. The domesticated Rhododendron chrysanthum Pall. had high amino acid and SOD contents. The study shows that the domesticated Rhododendron chrysanthum Pall. has significant UV-B resistance. The transcriptomics results show that the trends of DEGs after UV-B radiation were similar for both forms of R. chrysanthum : cellular process and metabolic process accounted for a higher proportion in biological processes, cellular anatomical entity accounted for the highest proportion in the cellular component, and catalytic activity and binding accounted for the highest proportion in the molecular function category. Through comparative study, the forms of metabolites resistant to UV-B stress in plants can be reflected, and UV-B radiation absorption complexes can be screened for application in future specific practices. Moreover, by comparing the differences in response to UV-B stress between the two forms of R. chrysanthum , references can be provided for cultivating domesticated plants with UV-B stress resistance characteristics. Research on the complex mechanism of plant adaptation to UV-B will be aided by these results.
- Published
- 2024
- Full Text
- View/download PDF
43. Effects of rpl1001 Gene Deletion on Cell Division of Fission Yeast and Its Molecular Mechanism.
- Author
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Yu W, Yuan R, Liu M, Liu K, Ding X, and Hou Y
- Abstract
The rpl1001 gene encodes 60S ribosomal protein L10, which is involved in intracellular protein synthesis and cell growth. However, it is not yet known whether it is involved in the regulation of cell mitosis dynamics. This study focuses on the growth, spore production, cell morphology, the dynamics of microtubules, chromosomes, actin, myosin, and mitochondria of fission yeast ( Schizosaccharomyces pombe ) to investigate the impact of rpl1001 deletion on cell mitosis. RNA-Seq and bioinformatics analyses were also used to reveal key genes, such as hsp16 , mfm1 and isp3 , and proteasome pathways. The results showed that rpl1001 deletion resulted in slow cell growth, abnormal spore production, altered cell morphology, and abnormal microtubule number and length during interphase. The cell dynamics of the rpl1001Δ strain showed that the formation of a monopolar spindle leads to abnormal chromosome segregation with increased rate of spindle elongation in anaphase of mitosis, decreased total time of division, prolonged formation time of actin and myosin loops, and increased expression of mitochondrial proteins. Analysis of the RNA-Seq sequencing results showed that the proteasome pathway, up-regulation of isp3 , and down-regulation of mfm1 and mfm2 in the rpl1001Δ strain were the main factors underpinning the increased number of spore production. Also, in the rpl1001Δ strain, down-regulation of dis1 caused the abnormal microtubule and chromosome dynamics, and down-regulation of hsp16 and pgk1 were the key genes affecting the delay of actin ring and myosin ring formation. This study reveals the effect and molecular mechanism of rpl1001 gene deletion on cell division, which provides the scientific basis for further clarifying the function of the Rpl1001 protein in cell division.
- Published
- 2024
- Full Text
- View/download PDF
44. QTL Mapping and Data Mining to Identify Genes Associated with Soybean Epicotyl Length Using Cultivated Soybean and Wild Soybean.
- Author
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Chen L, Ma S, Li F, Li L, Yu W, Yu L, Tang C, Liu C, Xin D, Chen Q, and Wang J
- Subjects
- Humans, Chromosome Mapping, Plant Breeding, Seeds metabolism, Data Mining, Quantitative Trait Loci, Glycine max genetics
- Abstract
Soybean ( Glycine max ) plants first emerged in China, and they have since been established as an economically important oil crop and a major source of daily protein for individuals throughout the world. Seed emergence height is the first factor that ensures seedling adaptability to field management practices, and it is closely related to epicotyl length. In the present study, the Suinong 14 and ZYD00006 soybean lines were used as parents to construct chromosome segment substitution lines (CSSLs) for quantitative trait loci (QTL) identification. Seven QTLs were identified using two years of epicotyl length measurement data. The insertion region of the ZYD00006 fragment was identified through whole genome resequencing, with candidate gene screening and validation being performed through RNA-Seq and qPCR, and Glyma.08G142400 was ultimately selected as an epicotyl length-related gene. Through combined analyses of phenotypic data from the study population, Glyma.08G142400 expression was found to be elevated in those varieties exhibiting longer epicotyl length. Haplotype data analyses revealed that epicotyl data were consistent with haplotype typing. In summary, the QTLs found to be associated with the epicotyl length identified herein provide a valuable foundation for future molecular marker-assisted breeding efforts aimed at improving soybean emergence height in the field, with the Glyma.08G142400 gene serving as a regulator of epicotyl length, offering new insight into the mechanisms that govern epicotyl development.
- Published
- 2024
- Full Text
- View/download PDF
45. Effect of Resin Content on the Structure, Water Resistance and Mechanical Properties of High-Density Bamboo Scrimbers.
- Author
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Yang Z, Meng X, Zeng G, Wei J, Wang C, and Yu W
- Abstract
Bamboo scrimber is acknowledged for its eco-friendly potential as a structural material. Its properties are significantly affected by both its density and resin content, but the effect of resin content on the properties under high density is not yet known. In this study, the microstructure, water resistance, mechanical properties, and thermal stability of bamboo scrimbers with varying resin content at a density of 1.30 g/cm
3 were investigated. The results unearthed that phenolic resin assisted in the densification of bamboo cells during hot pressing, and a higher resin content could effectively reduce the cracks in the scrimber. The inherent cellulose I structure remained unaffected, but an increase in resin content led to a noticeable decline in crystallinity. Additionally, an increase in resin content pronouncedly improved the water resistance and dimensional stability of bamboo scrimbers. The water absorption and thickness swelling were as low as 9.67% and 7.62%, respectively. The modulus of rupture (MOR) exhibited a marginal increase with the amount of resin, whereas the compressive strength and short-beam shearing strength first increased and then decreased. Their peak strengths were 327.87 MPa at a resin content of 15 wt.%, and 168.85 MPa and 25.96 MPa at 11 wt.%, respectively. However, phenolic resin accelerated the thermal decomposition of bamboo scrimbers, and more resin worsened the thermal stability. These research outcomes offer a dual advantage, providing both a theoretical foundation and concrete data that can inform the production and practical application of high-density bamboo scrimbers.- Published
- 2024
- Full Text
- View/download PDF
46. Design of Mantis-Shrimp-Inspired Multifunctional Imaging Sensors with Simultaneous Spectrum and Polarization Detection Capability at a Wide Waveband.
- Author
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Wang T, Wang S, Gao B, Li C, and Yu W
- Abstract
The remarkable light perception abilities of the mantis shrimp, which span a broad spectrum ranging from 300 nm to 720 nm and include the detection of polarized light, serve as the inspiration for our exploration. Drawing insights from the mantis shrimp's unique visual system, we propose the design of a multifunctional imaging sensor capable of concurrently detecting spectrum and polarization across a wide waveband. This sensor is able to show spectral imaging capability through the utilization of a 16-channel multi-waveband Fabry-Pérot (FP) resonator filter array. The design incorporates a composite thin film structure comprising metal and dielectric layers as the reflector of the resonant cavity. The resulting metal-dielectric composite film FP resonator extends the operating bandwidth to cover both visible and infrared regions, specifically spanning a broader range from 450 nm to 900 nm. Furthermore, within this operational bandwidth, the metal-dielectric composite film FP resonator demonstrates an average peak transmittance exceeding 60%, representing a notable improvement over the metallic resonator. Additionally, aluminum-based metallic grating arrays are incorporated beneath the FP filter array to capture polarization information. This innovative approach enables the simultaneous acquisition of spectrum and polarization information using a single sensor device. The outcomes of this research hold promise for advancing the development of high-performance, multifunctional optical sensors, thereby unlocking new possibilities in the field of optical information acquisition.
- Published
- 2024
- Full Text
- View/download PDF
47. Improving Wear Resistance and Corrosive Resistance of Cemented Carbide for Mud Pulser Rotor by Deep Cryogenic Treatment.
- Author
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Zhang W, Wu X, Tian J, Huang X, Yu W, Zhu W, and He J
- Abstract
Cemented carbide used in the rotor of a mud pulser is subjected to the scouring action of solid particles and corrosive mud media for a long time, which causes abrasive wear and electrochemical corrosion. To improve the wear and corrosive resistance of cemented carbide, samples with different cobalt content (WC-5Co, WC-8Co, and WC-10Co) receive deep cryogenic treatment (DCT) at -196 °C for 2.5 h. An optical metalloscope (OM) and X-ray diffractometer (XRD) are used to observe the phase changes of cemented carbides, and the XRD is also used to observe the change in residual stress on the cemented carbide's surface. A scanning electron microscope (SEM) is used to characterize the wear and electrochemical corrosion surface microstructure of cemented carbides (untreated and DCT). The results show that the DCT promotes the precipitation of the η phase, and the diffraction peak of ε-Co tends to intensify. Compared with the untreated, the wear rates of WC-5Co, WC-8Co, and WC-10Co can be reduced by 14.71%, 37.25%, and 41.01% by DCT, respectively. The wear form of the cemented carbides is mainly the extrusion deformation of Co and WC shedding. The precipitation of the η phase and the increase in WC residual compressive stress by DCT are the main reasons for the improvement of wear resistance. The electrochemical corrosion characteristic is the dissolution of the Co phase. DCT causes the corrosion potential of cemented carbide to shift forward and the corrosion current density to decrease. The enhancement of the corrosion resistance of cemented carbide caused by DCT is due to the Co phase transition, η phase precipitation, and the increase in the compressive stress of cemented carbide.
- Published
- 2024
- Full Text
- View/download PDF
48. The Fabrication of Ultrahigh-Strength Steel with a Nanolath Structure via Quenching-Partitioning-Tempering.
- Author
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Xu W, Xie L, Liu X, Wang J, Xu Y, He M, Hu K, Liu C, and Yu W
- Abstract
A novel low-alloy ultrahigh-strength steel featuring excellent mechanical properties and comprising a nanolath structure was fabricated in this work using a quenching-partitioning-tempering (Q-P-T) process. The Q-P-T process comprised direct quenching and an isothermal bainitic transformation for partitioning after thermo-mechanical control processing (online Q&P) and offline tempering (reheating and tempering). The ultrafine nanolath martensite/bainite mixed structure, combined with residual austenite in the form of a thin film between the nanolaths, was formed, thereby conferring excellent mechanical properties to the steel structures. After the Q-P-T process, the yield and tensile strengths of the steels reached 1450 MPa and 1726 MPa, respectively. Furthermore, the Brinell hardness and elongation rate were 543 HB and 11.5%, respectively, with an average impact energy of 20 J at room temperature.
- Published
- 2024
- Full Text
- View/download PDF
49. Application of CRISPR/Cas9 for Rapid Genome Editing of Pseudorabies Virus and Bovine Herpesvirus-1.
- Author
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Yu W, Liu J, Liu Y, Forlenza M, and Chen H
- Subjects
- Animals, Gene Editing, CRISPR-Cas Systems, Glycoproteins genetics, Herpesvirus 1, Suid, Herpesvirus 1, Bovine genetics, Herpesvirus 1, Bovine metabolism, Pseudorabies prevention & control
- Abstract
The CRISPR/Cas9 system is widely used to manipulate viral genomes. Although Alphaherpesvirinae genomes are large and complicated to edit, in recent years several Pseudorabies virus (PRV) mutants have been successfully generated using the CRISPR/Cas9 system. However, the application of CRISPR/Cas9 editing on another member of alpha herpesviruses, bovine herpesvirus-1 (BHV-1), is rarely reported. This paper reports a rapid and straightforward approach to manipulating herpesviruses genome using CRISPR/Cas9. The recombinant plasmids contained the left and right arm of the thymidine kinase ( TK ) gene of PRV or of the glycoprotein I ( gI ) and glycoprotein E ( gE ) of BHV-1. Upon the cleavage of the TK or gIgE gene by Cas9 protein, this was replaced by the enhanced green fluorescence protein ( eGFP ) by homologous recombination. With this approach, we generated recombinant TK-/eGFP+ PRV and gIgE-/eGFP+ BHV-1 mutants and then proceeded to characterize their biological activities in vitro and in vivo. In conclusion, we showed that alpha herpesvirus, including PRV and BHV-1, can be rapidly edited using the CRISPR/Cas9 approach paving the way to the development of animal herpesvirus vaccines.
- Published
- 2024
- Full Text
- View/download PDF
50. Solid-Phase Microextraction/Gas Chromatography-Time-of-Flight Mass Spectrometry Approach Combined with Network Pharmacology Analysis to Evaluate the Quality of Agarwood from Different Regions against Anxiety Disorder.
- Author
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Pang Y, Yu W, Liang W, Gao Y, Yang F, Zhu Y, Feng L, Yin H, and Liu Y
- Subjects
- Humans, Network Pharmacology, Solid Phase Microextraction, Anxiety Disorders, Gas Chromatography-Mass Spectrometry, Anti-Anxiety Agents pharmacology, Sesquiterpenes pharmacology
- Abstract
Agarwood ( Aquilaria malaccensis Lam.) is a resinous material from different geographical locations. The current evaluation of agarwood quality is usually based on its physical properties and chemical compounds, yet only a few studies have linked agarwood quality with its anxiolytic effect, as indicated by characteristic compounds. In this study, using solid-phase microextraction/gas chromatography-time-of-flight mass spectrometry (SPME/GC-TOFMS) and multivariate analysis, we found 116 significantly different compounds in agarwood samples from four locations in Southeast Asia with regard to their quality. Brunei and Nha Trang agarwood had abundant sesquiterpenoids, exhibiting notable pharmacological efficacy in relieving anxiety. Malaysian and Irian agarwood had abundant alcohols and aldehydes, qualifying them as high-quality spices. Compound-target-disease network and pathway enrichment analysis were further employed to predict 79 gene targets and 20 pathways associated with the anxiolytic effects based on the 62 sesquiterpenoids. The correlated relationships among the sesquiterpenoids and targets suggest that agarwood treats anxiety via multiple compounds acting on multiple targets. Varying levels of sesquiterpenes across agarwood groups might lead to differences in the anxiolytic effects via signaling pathways, such as neurotransmitter- and hormone-regulated pathways. Our study originally evaluates agarwood quality and its anxiolytic effect by linking the characteristic compounds to potential gene targets and pathways.
- Published
- 2024
- Full Text
- View/download PDF
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