5,432 results on '"Zhou, Wei"'
Search Results
2. Metabolic profiles of children aged 2–5 years born after frozen and fresh embryo transfer: A Chinese cohort study.
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Zhou, Wei, Feng, Wanbing, Chang, Jinli, Hu, Jingmei, Li, Fuxia, Hu, Kuona, Jiao, Jiejing, Xue, Xinyi, Lan, Ting, Wan, Wenjing, Chen, Zi-Jiang, and Cui, Linlin
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EMBRYO transfer , *REPRODUCTIVE technology , *HDL cholesterol , *COUPLES counseling , *BODY mass index - Abstract
Background: Frozen embryo transfer (FET) has become a widely employed assisted reproductive technology technique. There have historically been concerns regarding the long-term metabolic safety of FET technology in offspring due to pregnancy-induced hypertension and large for gestational age, both of which are well-recognized factors for metabolic dysfunction of children. Therefore, we aimed to compare the metabolic profiles of children born after frozen versus fresh embryo transfer at 2 to 5 years of age. Methods and findings: This was a prospective cohort study. Using data from the "Assisted Reproductive Technology borned KIDs (ARTKID)," a birth cohort of offspring born from assisted reproductive technology at the Institute of Women, Children and Reproductive Health, Shandong University, China. We included 4,246 singletons born after FET (n = 2,181) and fresh embryo transfer (n = 2,065) enrolled between 2008 and 2019 and assessed the glucose and lipid variables until the age of 2 to 5 years. During a mean follow-up of 3.6 years, no significant differences were observed in fasting blood glucose, fasting insulin, Homeostatic Model Assessment of Insulin Resistance Index, total cholesterol, triglycerides, low-density lipoprotein-cholesterol, and high-density lipoprotein-cholesterol levels between offspring conceived by fresh and frozen embryo transfer in the crude model and adjusted model (adjusted for parental age, parental body mass index, parental education level, paternal smoking, parity, offspring age and sex). These results remained consistent across subgroup analyses considering offspring age, the stage of embryo transfer, and the mode of fertilization. Results from sensitivity analysis on children matched for age within the cohort remains the same. The main limitation of our study is the young age of the offspring. Conclusions: In this study, the impact of FET on glucose and lipid profiles during early childhood was comparable to fresh embryo transfer. Long-term studies are needed to evaluate the metabolic health of offspring born after FET. Wei Zhou and co-workers explore the impact of fresh Versus frozen embryo transfer on the metabolic profiles of children in China. Author summary: Why was this study done?: Frozen embryo transfer (FET) is a commonly used assisted reproductive technology technique. Concerns have existed about the long-term metabolism of FET for offspring due to increased risk of well-recognized factors for metabolic dysfunction, including pregnancy-induced hypertension, macrosomia, large for gestational age, and elevated birth weight. Limited studies have reported on the metabolic profiles of children born after FET, leaving the potential long-term metabolic safety of FET unclear. What did the researchers do and find?: Using data from the "Assisted Reproductive Technology borned KIDs (ARTKID)," a prospective birth cohort at a Chinese single reproductive center, 4,246 singletons of "ARTKID" cohort at 2 to 5 years of age born after either FET (n = 2,181) or fresh embryo transfer (n = 2,065) were included. The average duration of follow-up across the study was 3.6 years. Assessments included fasting blood glucose, insulin, total cholesterol, triglycerides, low- and high-density lipoprotein cholesterol. The study found no significant differences in various metabolic parameters between children born after frozen versus fresh embryo transfer, even after adjusting for potential confounders, including parental age, body mass index, and other factors [adjusted mean difference (95% CI): fasting blood glucose, −0.01(−0.03, 0.02); total cholesterol, 0(−0.05, 0.04)]. What do these findings mean?: FET does not have a significant adverse impact on glucose and lipid profiles during early childhood. These data provide valuable evidence on the safety of FET when counselling couples undergoing assisted reproductive technology treatment. The main limitations are the young age of the offspring, as they may not fully manifest comprehensive metabolic phenotypic changes at this stage, necessitating longer follow-up studies for a more thorough understanding. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Predicting capacity models and seismic fragility estimation for precast parking structures based on machine learning techniques.
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Li, Hao and Zhou, Wei
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MACHINE learning , *EARTHQUAKE resistant design , *ARTIFICIAL neural networks , *SUPPORT vector machines , *RANDOM forest algorithms , *EARTHQUAKE engineering - Abstract
The development of fragility curves is an important step in seismic risk assessment within the scope of performance‐based earthquake engineering. The goal of this work is to use machine learning methods (regression‐based tools) to forecast the large‐span precast parking structural responses and fragility curves. This study proposes five predicting models based on machine learning to evaluate the seismic performance of the large‐span precast parking structures, including: neural networks, genetic algorithm‐based neural networks, support vector machine, decision tree and random forest. A database that includes 453 numerical synthetic results was used to train and test the machine learning models. The seismic performance of large‐span precast parking structures were predicted using the constructed machine learning models. Finally, the sensitivity analysis of input parameters was conducted. From this paper we can conclude that: (1) the genetic optimization‐based neural networks' predicting model has the most accurate predictive ability for seismic fragility estimation and (2) the structural responses and the fragility curves of parking structures are related to the differences of the stiffness of the connectors and the number of floors, of which the stiffness of the connectors should be given special attention. [ABSTRACT FROM AUTHOR]
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- 2024
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4. Phosphorus deficiency regulates the growth and photophysiology responses of an economic macroalga Gracilariopsis lemaneiformis to ocean acidification and warming.
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Zhou, Wei, Wu, Hui, Shi, Mengqi, Chen, Zeyu, Wang, Jinguo, and Xu, Juntian
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Ocean acidification and warming caused by elevated CO2 are urgent problems facing the marine ecological environment. With the strengthening of environmental governance in China, anthropogenic inputs of terrestrial phosphorus into the coastal ocean have drastically decreased, resulting in frequent phosphorus deficiency in seawater. These environmental factors in the future may affect algal growth, photosynthesis and yield. As an important economic macroalga suitable for large-scale cultivation, Gracilariopsis lemaneiformis is also potentially affected by the coupling of ocean acidification, warming and phosphorus deficiency. In this study, G. lemaneiformis was cultured outdoors under two pCO2 levels (LC, 400 μatm; HC, 1000 μatm), two temperatures (LT, 20 ℃; HT, 24 ℃) and two phosphorus concentrations (LP, 0.1 μmol L−1; HP, 10 μmol L−1) to investigate its growth and photosynthetic performance. The results showed that LP significantly decreased the relative growth rates (RGR) and the maximum photosynthesis rate (Pm) of G. lemaneiformis both under LC and HC conditions. Under P depletion condition, the effects of warming and ocean acidification on the growth and photosynthetic performance of G. lemaneiformis showed an opposite trend, that is, HC caused a decrease in the growth, Pm, maximum relative electron transfer rate (rETRmax) and light utilization efficiency (α) from the rapid light response curve of G. lemaneiformis, and HT improved these parameters. Under LP condition, HC significantly inhibited the RGR of G. lemaneiformis in the LT group but had no significant effect on RGR in the HT group. Additionally, under LP condition, HC insignificantly affected PE and PC contents in the LT group, but significantly reduced these contents in the HT group. These findings suggest that phosphorus deficiency results in a decline in the growth of G. lemaneiformis and, under LP condition, the inhibition effect of ocean acidification on the growth of G. lemaneiformis could be mitigated by warming. This study provides scientific guidance for the field cultivation and selective breeding of G. lemaneiformis in phosphorus-deficient seawater under global climate change. [ABSTRACT FROM AUTHOR]
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- 2024
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5. The Crystallization Behavior of L-Poly(lactic acid)/Polypropylene Blends: The Acceleration for Both L-Poly(lactic acid) and Polypropylene.
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Li, Shuang-Cheng, Zhou, Wei-Jia, Wu, Wen-Jie, Shao, Jun, Chen, Shui-Liang, Hou, Hao-Qing, and Xiang, Sheng
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POLYMER blends , *LACTIC acid , *CRYSTALLIZATION , *MELT crystallization , *POLYPROPYLENE , *CRYSTAL structure - Abstract
For a polymer/polymer dismissible blend with two crystallizable components, the crystallization behavior of different components and the reciprocal influences between different crystals are interesting and important, but did not investigate in detail. In this study, the L-poly(lactic acid)/polypropylene (PLLA/PP) blends with different weight ratios were prepared by melt mixing and the crystallization behavior of the blends were investigated. Results showed that the crystalline structures of PLLA and PP were not altered by the composition. For the crystallization of PLLA, both the diffusion of chain segments and crystallization rate were enhanced under the existence of PP crystals. For the crystallization of PP, its crystallization rate was depressed under the existence of amorphous PLLA molecular chains. When the PP crystallized from the existence of PLLA crystals, although the diffusion rate of PP was reduced by PLLA crystals, the nucleation positions were obviously enhanced, which accelerated the formation of PP crystals. This investigation would supply more basic data for the application of PLLA/PP blend. [ABSTRACT FROM AUTHOR]
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- 2024
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6. GROUPS WITH FEW NONPOWER SUBGROUPS.
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ZHENG, JIWEI, ZHOU, WEI, and TAYLOR, D. E.
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COUNTING - Abstract
For a group G and $m\ge 1$ , let $G^m$ denote the subgroup generated by the elements $g^m$ , where g runs through G. The subgroups not of the form $G^m$ are the nonpower subgroups of G. We classify the groups with at most nine nonpower subgroups. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Assessment of Remaining Seismic Capacity for Reinforced Concrete Piers Based on a Residual Drift Response: Static Analysis.
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Geng, Xiangri and Zhou, Wei
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SEISMIC response , *REINFORCED concrete , *PIERS , *LATERAL loads , *ENERGY dissipation , *PREDICTION models - Abstract
To investigate the correlationf between residual drift and remaining seismic capacity, 24 reinforced concrete pier specimens were subjected to lateral load reversals. By normalizing the specified drift against the value at specimen failure, the normalized residual drift exhibits a strong correlation with the normalized lateral drift, thereby providing a predictive model for residual drift. After determining the remaining seismic capacity derived from energy dissipation, a linear correlation was established between the normalized residual drift and the remaining seismic capacity. Consequently, normalized residual drift was selected as a performance indicator for seismic assessment, enabling the quantitative determination of structural damage states. [ABSTRACT FROM AUTHOR]
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- 2024
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8. Visualizing Carrier Diffusion in Cs‐Doping FAPbI3 Perovskite Thin Films Using Transient Absorption Microscopy.
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Xie, Junhan, Zhou, Wei, Li, Haozheng, Wang, Ziyu, Jiang, Jiaming, Zhang, Yile, Shen, Xiaoqin, Ning, Zhijun, and Liu, Weimin
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The determination of the semiconducting materials performance heavily relies on the diffusion coefficient and length of the carrier. Recently, significant progress is made in enhancing solar cell efficiency through improved carrier diffusion in perovskite thin films. However, the spatial‐temporal mechanisms underlying carrier transport remain unclear. Recent advancements in utilizing transient absorption microscopy (TAM) offer promising opportunities to directly visualize the carrier transport dynamics within perovskite films. Here, the wide‐field imaging TAM combined with X‐ray diffraction and scanning electron microscopy is employed to investigate the spatial‐temporal carrier transport dynamics in FA1−xCsxPbI3 perovskites with varying Cs doping ratios. The experimental results indicate that the diffusion constant remains consistent regardless of the excitation power. Moreover, a decrease in the Cs doping ratio leads to an increase in the diffusion length within FA1−xCsxPbI3 perovskites. The measurements reveal a highest diffusion coefficient of up to 0.085 cm2 s−1 and a maximum diffusion length of ≈1.4 µm in FA0.97Cs0.03PbI3. Comparative analysis of short‐circuit current density, open‐circuit voltage, fill factor, and power conversion efficiency demonstrates that FA0.97Cs0.03PbI3 exhibits superior device efficiency. The TAM visualizes spatial/ temporal carrier diffusion dynamics, showing a significant correlation with device efficiency and thus providing valuable insights for further enhancing device performance. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Copy number variants at 4q31.3 affecting the regulatory region of FBXW7 associated with neurodevelopmental delay.
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Zhou, Wei, Wang, Chunli, Fu, Luhan, Shi, Wei, Zhang, Aihua, Jia, Zhanjun, Zhao, Xiaoke, Fu, Dalin, and Zheng, Bixia
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Emerging research has demonstrated that genomic alterations disrupting topologically associated domains (TADs) and chromatin interactions underlie the pathogenic mechanisms of specific copy number variants (CNVs) in neurodevelopmental disorders. We report two patients with a de novo deletion and a duplication in chromosome 4q31, potentially causing FBX‐related neurodevelopmental syndrome by affecting the regulatory region of FBXW7. High‐throughput chromosome conformation capture (Hi‐C) analysis using available capture data in neural progenitor cells revealed the rewiring of the TAD boundary close to FBXW7. Both patients exhibited facial dysmorphisms, cardiac and limb abnormalities, and neurodevelopmental delays, showing significant clinical overlap with previously reported FBXW7‐related features. We also included an additional 10 patients with CNVs in the 4q31 region from the literature and the DECIPHER database for Hi‐C analysis, which confirmed that disruption of the regulatory region of FBXW7 likely contributes to the developmental defects observed in these patients. [ABSTRACT FROM AUTHOR]
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- 2024
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10. Predictive value of preoperative CT enhancement rate and CT perfusion parameters in colorectal cancer.
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Li, Ze-mao, Zhou, Wei, Feng, Li, Zhang, Hui-ying, and Chen, Wei-bin
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COLORECTAL cancer , *VASCULAR endothelial growth factors , *PEARSON correlation (Statistics) , *PERFUSION , *TREFOIL factors - Abstract
Background: Angiogenesis is a critical step in colorectal cancer growth, progression and metastasization. CT are routine imaging examinations for preoperative clinical evaluation in colorectal cancer patients. This study aimed to investigate the predictive value of preoperative CT enhancement rate (CER) and CT perfusion parameters on angiogenesis in colorectal cancer, as well as the association of preoperative CER and CT perfusion parameters with serum markers. Methods: This retrospective analysis included 42 patients with colorectal adenocarcinoma. Median of microvessel density (MVD) as the cut-off value, it divided 42 patients into high-density group (MVD ≥ 35/field, n = 24) and low-density group (MVD < 35/field, n = 18), and 25 patients with benign colorectal lesions were collected as the control group. Statistical analysis of CER, CT perfusion parameters, serum markers were performed in all groups. Receiver operating curves (ROC) were plotted to evaluate the diagnostic efficacy of relevant CT perfusion parameters for tumor angiogenesis; Pearson correlation analysis explored potential association between CER, CT perfusion parameters and serum markers. Results: CER, blood volume (BV), blood flow (BF), permeability surface (PS) and carbohydrate antigen 19 − 9 (CA19-9), carbohydrate antigen 125 (CA125), carcinoembryonic antigen (CEA), trefoil factor 3 (TFF3), vascular endothelial growth factor (VEGF) in colorectal adenocarcinoma were significantly higher than those in the control group, the parameters in high-density group were significantly higher than those in the low-density group (P < 0.05); however, the time to peak (TTP) of patients in colorectal adenocarcinoma were significantly lower than those in the control group, and the high-density group showed a significantly lower level compared to the low-density group (P < 0.05). The combined parameters BF + TTP + PS and BV + BF + TTP + PS demonstrated the highest area under the curve (AUC), both at 0.991. Pearson correlation analysis showed that the serum levels of CA19-9, CA125, CEA, TFF3, and VEGF in patients showed positive correlations with CER, BV, BF, and PS (P < 0.05), while these indicators exhibited negative correlations with TTP (P < 0.05). Conclusions: Some single and joint preoperative CT perfusion parameters can accurately predict tumor angiogenesis in colorectal adenocarcinoma. Preoperative CER and CT perfusion parameters have certain association with serum markers. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Guided Organic Crystalline Nanowires by Directional Friction‐Transferred Poly(Tetrafluoroethylene) Nanogrooves and Their Monolithic Phototransistors.
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Li, Yajun, Zhou, Wei, Cai, Xuebao, Chen, Xiangtao, Liu, Hanyu, Huang, Pingyang, Wang, Xingyu, and Xu, Jinyou
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PHOTOTRANSISTORS , *TETRAFLUOROETHYLENE , *NANOWIRES , *SUBSTRATES (Materials science) , *SILICON nanowires , *ELECTRODES , *FRICTION - Abstract
The monolithic integration of bottom‐up nanowires into devices requires rational growth of aligned nanowires. Of the proposed aligned growth methods, few are sufficiently general to be applicable to diverse materials and substrates. In this work, oriented poly(tetrafluoroethylene) (PTFE) grooves with nanoscale depth and width are transferred onto different substrates through a simple directional mechanical friction. This friction is achieved in a few seconds by a program‐driven handwriting machine. Various organic molecules (e.g., Alq3, NiPc, CoPc, CuPc, F16CuPc) are therefore assembled into oriented crystalline nanowires on the surface of Si, Si/SiO2, and glass. The self‐alignment of these nanowires enables a scalable device fabrication directly on growth substrates, eliminating structural damage and contamination during post‐growth alignment. For example, using the aligned F16CuPc nanowires on PTFE‐coated Si/SiO2 wafers, back‐gate field‐effect phototransistors are fabricated in a scalable manner by directly depositing an array of micro‐sized electrodes. Statistical results show that these phototransistors operate in n‐type enhancement mode with thresholds of a few volts. In addition, they exhibit fast photoresponse on the order of tens of milliseconds and long‐term stability in the vis–NIR spectrum. The generality of this guided nanowire growth and resulting monolithic devices offer new opportunities for the monolithic integration of nanowire‐based devices. [ABSTRACT FROM AUTHOR]
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- 2024
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12. Prediction of rainfall-induced debris flow using Random Forests and Bayesian Optimization in Yingxiu Town, Wenchuan County, China.
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Liu, Renwen, Zhou, Wei, Yin, Huaqiang, Ren, Wenming, Feng, Jianguo, and Deng, Jiulin
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Mountainous areas are susceptible to rainfall-induced debris flows. An accurate debris flow forecast helps reduce disaster damage and casualties. Conventional forecasting methods, which primarily concentrate on precipitation data, exhibit limitations by neglecting other crucial variables. This study aims to address this gap by constructing an advanced Random Forest model that integrates a diverse range of factors linked to rainfall-induced debris flows. To do this, we compiled data on Yingxiu Town, including historical debris flow events and 19 potential influencing factors. Through rigorous feature selection, we focused on the key factors from the dataset. Our refined Random Forest model integrates critical variables such as fractional vegetation cover, landslide ratio, and a suite of rainfall metrics encompassing average intensity, duration, and cumulative precipitation, accounting for both antecedent and current rainfall events. To enhance the model efficiency, we opted for an automated approach to optimize hyperparameters. This involved utilizing Bayesian optimization to determine the optimal configurations for our model. This customized approach yielded a model that excelled in predictive performance when compared to a more generalized model incorporating all potential factors. On the test dataset, the model achieved an F1 score of 0.57, an accuracy of 0.9, and a significant area under the ROC curve (AUC) of 0.87. Beyond its predictive success, our study offered insights into the mechanics of hyperparameter tuning and provided a nuanced understanding of decision tree construction within the Random Forests algorithm. The contributions of our research offer valuable guidance for enhancing debris flow risk mitigation strategies. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Corrosion behavior of Fe-containing silicate over ytterbium hafnate ceramics with different HfO2 content.
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Zhou, Wei, Ren, Yutong, Sun, Zhipeng, He, Ling, Pan, Ling, Xiao, Peng, and Li, Yang
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YTTERBIUM , *THERMAL barrier coatings , *OXIDE ceramics , *CERAMICS , *SILICATES - Abstract
High-temperature molten silicate deposit corrosion has become a critical factor for the failure of thermal barrier coatings. In this work, promising ytterbium hafnate ceramics with different HfO 2 content were prepared by solid-phase reaction, and the effect of HfO 2 content on Fe-containing silicate corrosion behavior of ytterbium hafnate ceramics was investigated. The evolution of HfO 2 content showed negligible influences on reaction products and corrosion mechanism. The attack of Fe-containing silicate melts on the ceramic led to the formation of a reaction layer consisting of apatite, fluorite, and garnet. This layer plays a critical role in preventing further penetration of the melts. However, ytterbium hafnate ceramics with lower HfO 2 content showed better resistance to melt attack. [ABSTRACT FROM AUTHOR]
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- 2024
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14. Biocompatible sodium alginate–silk fibroin antibacterial microspheres from a microfluidic platform for infected wound repair.
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Liu, Jinglong, Zhou, Wei, Yang, Shuo, Chu, Ruixue, Zhen, Yuqi, Ding, Rui, Xu, Juan, Qian, Zhiyong, and Wen, Ning
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WOUND healing , *MICROSPHERES , *CONTROLLED release drugs , *DRUG carriers , *DRUG delivery systems , *SILVER nanoparticles , *EXOTOXIN - Abstract
Micro/nano drug delivery systems can provide ideal controlled drug release. Microfluidic chip technology plays an important role in the preparation of microspheres. Sodium alginate (SA) has been used to prepare microspheres as drug carriers owing to its good biosafety and easy preparation. However, these microspheres lack antimicrobial activity and drug loading efficiency, which prevent their application for infected wound repair. Although silver nanoparticles (AgNPs) possess broad-spectrum antibiotic activity, liquid mixtures of AgNPs and SA are too unstable to fabricate drug-loaded microspheres using microfluidic chip technology. In this study, AgNPs were coated with silk fibroin (SF) and then dispersed in SA solution to fabricate antibacterial microspheres (denoted SA-SF-Ag) using microfluidic chip technology. SA-SF-Ag effectively inhibited the growth of microorganisms and gradually released AgNPs. Moreover, in vivo results showed that SA-SF-Ag promoted infected wound healing and angiogenesis by killing Pseudomonas aeruginosa on the surface of infected skin wounds of mouse models. This study offers a new method to integrate AgNPs into organic polymeric microspheres for the treatment of infected wounds. [ABSTRACT FROM AUTHOR]
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- 2024
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15. Ionosphere disturbances on GNSS signal and positioning performance: Analysis of the solar flare and geomagnetic storm events in September 2017 and October 2021.
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Zhou, Wei, Yuan, Yongqiang, Tang, Chengpan, Meng, Yinan, and Chen, Ying
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GLOBAL Positioning System , *SOLAR flares , *IONOSPHERE , *SOLAR activity , *HURRICANE Harvey, 2017 , *MAGNETIC storms - Abstract
Ionosphere has important influences on the performances of Global Navigation Satellite System (GNSS) in terms of signal quality and ranging errors. This study discusses the impact of ionosphere disturbances caused by the solar flare and geomagnetic storm events in September 2017 and October 2021 on signal quality and positioning accuracy. To identify the occurrence and also to study the magnitude of the storm, we have evaluated the Solar Activity parameters and constructed global Rate of TEC Index maps. In regard of the GNSS signal, both the signal-in-space ranging error and cycle slip occurrence are adopted to study the influence of the solar flare on the accuracy of the broadcast ephemeris and the quality of phase observation. Furthermore, the kinematic precise point positioning experiments with 39 International GNSS Service (IGS) stations are carried out, and the positioning errors of north, east, and up components are calculated to assess the precise positioning accuracy during the storm. The presented results suggest that the kinematic precise point positioning accuracy of the selected IGS stations in low- and high-latitude areas degraded at 8th September 2017 and 12th October 2021, implying that the GNSS precise positioning are less reliable during the solar flare events. [ABSTRACT FROM AUTHOR]
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- 2024
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16. Acoustic emission source location for composite tubes using finite element simulation and machine learning.
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Zhou, Wei, Liang, Ya-Zhao, Xue, Sai-Nan, and Ma, Lian-Hua
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Acoustic emission is widely used in engineering structural health monitoring, where damage location based on acoustic emission have great advantages. Currently, most of the acoustic emission location work requires extensive experimental studies. In this study, acoustic emission source location model was proposed based on BP neural network and acoustic emission wave propagation simulation, thus reduced the experiments required for acoustic emission localisation and improved the location accuracy. Initially, finite element simulation was conducted to study the propagation of acoustic emission waves in composite tubes. The calculated findings showed a high level of agreement with the experimental data. Additionally, the first arrival time of the signal was extracted according to the Akaike information criterion, and the neural network was trained and tested using the simulated data, while the trained network model was validated using the experimental data. The results show that the finite element method is a reliable alternative test method. More than 94% of the sound source location results have absolute location error within ± 3 mm, and the all points is less than ± 5 mm. The deviation of the location results showed significant improvement compared to the traditional time difference of arrival method, verifying the feasibility of the method. [ABSTRACT FROM AUTHOR]
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- 2024
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17. Temperature‐responsive palm oil‐based‐oleogels for encapsulation of D‐limonene: effect of fat crystallisation and melting point.
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Liu, Yanping, Zhou, Wei, Gao, Hongxia, Chen, Mianhong, Li, Ruyi, Dai, Yaping, Zou, Ying, Yuan, Yuan, Zhang, Chenghui, and Li, Jihua
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MELTING points , *CRYSTALLIZATION , *BASE oils , *CRYSTAL morphology , *ESSENTIAL oils , *LOW temperatures , *FAT , *MILKFAT - Abstract
Summary: D‐limonene is an important flavouring ingredient with a wide range of applications. However, its high volatility and low stability have severely impacted its application in the food industry. To address these limitations, temperature‐flavour release control system is expected to be established to reduce the loss of D‐limonene during processing and storage, as well as to control its release by temperature. The aim of the current study is to construct an oleogel system to encapsulate D‐limonene using carnauba wax as a gelling agent and palm oils (POs) as the base oil. POs with 24 °C, 38 °C, 42 °C, 48 °C, and 52 °C melting points were selected to systematically investigate the effects of the base oil melting point on the crystal morphology, interactions, physicochemical properties, microstructure, and D‐limonene release of the oleogels. The enthalpy of melting, enthalpy of crystallisation, hardness, stickiness, and gel strength increased in oleogels prepared using POs with a higher melting point. In addition, the oil‐binding capacity (OBC) (>95%) of the oleogels increased with the base oil melting point, while the fat crystal distribution became more homogeneous and denser. Based on the influence that extraction temperature has on the concentration of released D‐limonene (a lower concentration of aroma was released from high‐melting‐point POs oleogels at low temperatures (<1.9 mg mL−1), whereas the control group released >2.5 mg mL−1), suitable POs can be selected to achieve the release or retention of the aroma. These results demonstrate that a temperature‐responsive flavour delivery system can be prepared with different PO melting points. The molecular dynamics of flavour release revealed that storage temperature and fat crystalline state impact the cumulative release rate of D‐limonene. [ABSTRACT FROM AUTHOR]
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- 2024
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18. Measurement Method for Contact Wire Wear Based on Stereovision.
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Zhou, Wei, Qin, Zhe, Du, Xinyu, Xue, Xiantang, Wang, Haiying, and Li, Hailang
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OPTICAL measurements , *CONDITION-based maintenance , *DYNAMIC testing , *CATENARY , *MEASUREMENT - Abstract
The contact wire wear is an important parameter to ensure the safety operation of electric railways. The contact wire may break if the wear is serious, which leads to transportation interruptions. This study proposes an optical measurement method of contact wire wear, using stereovision technology. The matching method of stereovision based on line-scan cameras is proposed. A lookup-table method is developed to exactly determine the image resolution caused by the contact wire being in different spatial positions. The wear width of the contact wire is extracted from catenaries' images, and the residual thickness of the contact wire is calculated. The method was verified by field tests. The round-robin tests of the residual thickness at the same location present excellent measurement repetitiveness. The maximum difference value between dynamic test results and ground measurement results is 0.13 mm. This research represents a potential way to implement condition-based maintenance for contact wire wear in the future in order to improve the maintenance efficiency and ensure the safety of catenary infrastructure. [ABSTRACT FROM AUTHOR]
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- 2024
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19. Analysis of the Curing Deformation of Polyurethane Composite Solar Cell Bezels.
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Wu, Rui, Zhou, Wei, Fan, Zhenhua, Zhou, Wenxing, and Xiong, Yongji
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SOLAR cells , *DEFORMATIONS (Mechanics) , *POLYURETHANES , *CURING , *PULTRUSION - Abstract
In the present study, we investigated the deformation of polyurethane composite solar cell bezels during the curing process. To address the problem of deformation, thermochemical and curing kinetics models were developed to investigate the mechanical behavior of the resin during the curing process. The importance of the influencing factors was determined through orthogonal experiments and simulation analysis. The results showed that holding pressure had a significant effect on the amount of deformation of the bezel, followed by curing temperature, pultrusion speed, and holding time. The optimal combination of process parameters was a curing temperature of 150 °C, a pultrusion speed of 50 cm/min, a holding time of 12 s, and a holding pressure of 0.14 MPa, which aided in significantly reducing the deformation of the bezel and achieving effective control of curing deformation. [ABSTRACT FROM AUTHOR]
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- 2024
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20. Time frequency domain combined deconvolution method.
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Zhou, Wei, Zhou, Huailai, Long, Dan, Yan, Haitao, and Liu, Junping
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ATTENUATION of seismic waves , *SEISMIC waves , *DECONVOLUTION (Mathematics) , *THEORY of wave motion - Abstract
In the process of seismic wave propagation, high-frequency energy is absorbed and attenuated by the stratum, and the dominant frequency and resolution decrease. To recover the energy of the high-frequency attenuation of seismic waves, a high-resolution processing method of time–frequency domain combined deconvolution (TFCD) is proposed. This method is different from the traditional time–frequency domain deconvolution because it considers the theory that the wavelet amplitude spectrum is smooth and has a low frequency. Wavelet separation is first conducted in the secondary spectral domain of seismic records and then smoothed in the log-domain to extract the time–frequency domain wavelet, which improves the accuracy of time–frequency domain deconvolution. This method comprehensively considers the wavelet shape and frequency characteristics, and can effectively improve seismic data resolution. [ABSTRACT FROM AUTHOR]
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- 2024
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21. Hypoxia promotes metastasis by relieving miR-598-3p-restricted glycolysis in gastric cancer.
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Zhou, Wei, Tang, Mengyuan, He, Dan, Shen, Yi, Huang, Ziwei, Xia, Wenxin, Wu, Zhiyun, Wei, Wenxiang, Zheng, Hui, Wang, Qi, Shi, Weifeng, and Jiang, Jingting
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STOMACH cancer , *GLYCOLYSIS , *ENERGY metabolism , *HYPOXEMIA , *GLUCOSE metabolism - Abstract
The activation of glycolysis, particularly in the context of reprogrammed energy metabolism, is increasingly recognized as a significant characteristic of cancer. However, the precise mechanisms by which glycolysis is promoted in metastatic gastric cancer cells under normal oxygen conditions remain poorly understood. MicroRNAs (miRNAs) play a crucial role in the development of malignant phenotypes in gastric cancer. Nevertheless, our understanding of the specific involvement of miRNAs in hypoxia-induced metabolic shifting and the subsequent metastatic processes is limited. Hypoxia-induced downregulation of miR-598-3p mechanistically leads to the upregulation of RMP and IGF1r, thereby promoting glycolysis. Either overexpression of miR-598-3p or R406 treatment effectively suppresses the metastasis of gastric cancer cells both in vitro and in vivo. Collectively, the depletion of miR-598-3p alters glucose metabolism from oxidative phosphorylation to glycolysis, thereby exacerbating the malignancy of gastric cancer cells. The present findings indicate a potential target for the development of therapeutics against gastric cancers with increased miR-598-3p expression. [ABSTRACT FROM AUTHOR]
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- 2024
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22. Metal‐Organic Frameworks: Direct Synthesis by Organic Acid‐Etching and Reconstruction Disclosure as Oxygen Evolution Electrocatalysts.
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Wang, Xiao, Zhou, Wei, Zhai, Shengliang, Chen, Xiaokang, Peng, Zheng, Liu, Zhi, Deng, Wei‐Qiao, and Wu, Hao
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METAL-organic frameworks , *HYDROGEN evolution reactions , *ELECTROCATALYSTS , *ORGANIC synthesis , *FOURIER transform infrared spectroscopy , *STRUCTURE-activity relationships , *OXYGEN evolution reactions - Abstract
Metal‐organic frameworks (MOFs) have emerged as promising oxygen evolution reaction (OER) electrocatalysts. Chemically bonded MOFs on supports are desirable yet lacking in routine synthesis, as they may allow variable structural evolution and the underlying structure‐activity relationship to be disclosed. Herein, direct MOF synthesis is achieved by an organic acid‐etching strategy (AES). Using π‐conjugated ferrocene (Fc) dicarboxylic acid as the etching agent and organic ligand, a series of MFc‐MOF (M=Ni, Co, Fe, Zn) nanosheets are synthesized on the metal supports. The crystal structure is studied using X‐ray diffraction and low‐dose transmission electron microscopy, which is quasi‐lattice‐matched with that of the metal, enabling in situ MOF growth. Operando Raman and attenuated total reflectance Fourier transform infrared spectroscopy disclose that the NiFc‐MOF features dynamic structural rebuilding during OER. The reconstructed one showing optimized electronic structures with an upshifted total d‐band center, high M−O bonding state occupancy, and localized electrons on adsorbates indicated by density functional theory calculations, exhibits outstanding OER performance with a fairly low overpotential (130 mV at 10 mA cm−2) and good stability (144 h). The newly established approach for direct MOF synthesis and structural reconstruction disclosure stimulate the development of more prudent catalysts for advancing OER. [ABSTRACT FROM AUTHOR]
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- 2024
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23. Metal‐Organic Frameworks: Direct Synthesis by Organic Acid‐Etching and Reconstruction Disclosure as Oxygen Evolution Electrocatalysts.
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Wang, Xiao, Zhou, Wei, Zhai, Shengliang, Chen, Xiaokang, Peng, Zheng, Liu, Zhi, Deng, Wei‐Qiao, and Wu, Hao
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METAL-organic frameworks , *HYDROGEN evolution reactions , *ELECTROCATALYSTS , *ORGANIC synthesis , *FOURIER transform infrared spectroscopy , *STRUCTURE-activity relationships , *OXYGEN evolution reactions - Abstract
Metal‐organic frameworks (MOFs) have emerged as promising oxygen evolution reaction (OER) electrocatalysts. Chemically bonded MOFs on supports are desirable yet lacking in routine synthesis, as they may allow variable structural evolution and the underlying structure‐activity relationship to be disclosed. Herein, direct MOF synthesis is achieved by an organic acid‐etching strategy (AES). Using π‐conjugated ferrocene (Fc) dicarboxylic acid as the etching agent and organic ligand, a series of MFc‐MOF (M=Ni, Co, Fe, Zn) nanosheets are synthesized on the metal supports. The crystal structure is studied using X‐ray diffraction and low‐dose transmission electron microscopy, which is quasi‐lattice‐matched with that of the metal, enabling in situ MOF growth. Operando Raman and attenuated total reflectance Fourier transform infrared spectroscopy disclose that the NiFc‐MOF features dynamic structural rebuilding during OER. The reconstructed one showing optimized electronic structures with an upshifted total d‐band center, high M−O bonding state occupancy, and localized electrons on adsorbates indicated by density functional theory calculations, exhibits outstanding OER performance with a fairly low overpotential (130 mV at 10 mA cm−2) and good stability (144 h). The newly established approach for direct MOF synthesis and structural reconstruction disclosure stimulate the development of more prudent catalysts for advancing OER. [ABSTRACT FROM AUTHOR]
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- 2024
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24. Statistical analysis of locked mode induced disruption in EAST.
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Zhou, Wei-Ran, Deng, Guo-Hong, Sun, You-Wen, Wang, Hui-Hui, Zhou, Deng, Shi, Tong-Hui, Gu, Shuai, Ye, Cheng, Ma, Qun, Zang, Qing, He, Kai-Yang, Chen, Da-Long, Shen, Biao, Jia, Man-Ni, Luo, Zheng-Ping, Liu, Hai-Qing, Zhou, Zi-Qiang, and Zhang, Tao
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STATISTICS , *ELECTRON temperature , *INTERVAL analysis , *PHYSICAL constants , *ELECTRON plasma , *ELECTRON density , *MAGNETIC flux leakage , *PLASMA boundary layers - Abstract
The effects of key parameters on locked mode induced disruption (LMiD) are investigated in EAST experiments. The experimental data for locked mode are collected from 2015 to 2022 when the externally applied resonant magnetic perturbation is successfully employed in EAST. In this dataset, ∼42% of the total shots are LMiD, while the remaining 58% are LM without disruption. To better analyze the LMiD, an intuitive physical process is proposed. The LMiD process can be divided into two stages, the evolution of magnetic islands and the loss of plasma stored energy. The LMiD can also be related to the evolution of the other 8 physical quantities. On the basis of this physical process analysis, the time scale and the influencing factors for LMiD are investigated using statistical analysis. It is found that the density (ne), the distance from the magnetic island outer boundary to the plasma last closed surface (dedge), the loop-voltage (Vloop), and the plasma core electron temperature (Te), which are consistent with the intuitive physical model, are key parameters to LMiD. In addition, other potentially important parameters, the relevant reasons, and statistical analysis on the parameter intervals where rapid disruption with greater harmfulness occurred have also been investigated. [ABSTRACT FROM AUTHOR]
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- 2024
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25. Verteporfin induces lipid peroxidation and ferroptosis in pancreatic cancer cells.
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Zhou, Wei, Lim, Adrian, Elmadbouh, Omer Hany Miligy, Edderkaoui, Mouad, Osipov, Arsen, Mathison, Angela J., Urrutia, Raul, Liu, Tao, Wang, Qiang, and Pandol, Stephen J.
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PANCREATIC cancer , *HIPPO signaling pathway , *CANCER cells , *PEROXIDATION , *YAP signaling proteins , *GLUTATHIONE peroxidase - Abstract
Pancreatic ductal adenocarcinoma (PDAC) has extremely poor prognosis, with a 5-year survival rate of approximately 11 %. Yes-associated protein (YAP) is a major downstream effector of the Hippo-YAP pathway and plays a pivotal role in regulation of cell proliferation and organ regeneration and tumorigenesis. Activation of YAP signaling has been associated with PDAC progression and drug resistance. Verteporfin (VP) is a photosensitizer used for photodynamic therapy and previous work showed that it can function as a YAP inhibitor. The efficacy of VP on human cancer are being tested in several trials. In this study, we examined the effect of VP on reactive oxygen species (ROS) and lipid peroxidation in pancreatic cancer cells, by using fluorescent molecular probes and by measuring the levels of malondialdehyde, a metabolic byproduct and marker of lipid peroxidation. We found that VP causes rapid increase of both overall ROS and lipid peroxide levels, independent of light activation. These effects were not dependent on YAP, as knockdown of YAP did not cause ROS or lipid peroxidation or enhance VP-induced ROS production. Temoporfin, another photodynamic drug, did not show similar activities. In addition, VP treatment led to loss of cell membrane integrity and reduction of viability. Notably, the activity of VP to induce lipid peroxidation was neutralized by ferroptosis inhibitors ferrostatin-1 or liproxstatin-1. VP treatment also reduced the levels of glutathione peroxidase 4 (GPX4), an enzyme that protects against lipid peroxidation. These results indicate that VP can induce lipid peroxidation and ferroptosis in the absence of light activation. Our findings reveal a novel mechanism by which VP inhibits tumor growth and provide insights into development of new therapeutic strategies for the treatment of pancreatic cancer. [Display omitted] • Verteporfin induces lipid peroxidation and ferroptosis-like cell death independent of light activation. • Verteporfin disrupts mitochondrial functions. • Verteporfin-induced ROS and mitochondrial changes are rapid and independent of YAP. • Verteporfin treatment decreases GPX4 and increase ATF3 expression levels. [ABSTRACT FROM AUTHOR]
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- 2024
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26. Profiles of subgingival microbiomes and gingival crevicular metabolic signatures in patients with amnestic mild cognitive impairment and Alzheimer's disease.
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Qiu, Che, Zhou, Wei, Shen, Hui, Wang, Jintao, Tang, Ran, Wang, Tao, Xie, Xinyi, Hong, Bo, Ren, Rujing, Wang, Gang, and Song, Zhongchen
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AMNESTIC mild cognitive impairment , *PORPHYROMONAS gingivalis , *ALZHEIMER'S disease , *LIQUID chromatography-mass spectrometry - Abstract
Background: The relationship between periodontitis and Alzheimer's disease (AD) has attracted more attention recently, whereas profiles of subgingival microbiomes and gingival crevicular fluid (GCF) metabolic signatures in AD patients have rarely been characterized; thus, little evidence exists to support the oral-brain axis hypothesis. Therefore, our study aimed to characterize both the microbial community of subgingival plaque and the metabolomic profiles of GCF in patients with AD and amnestic mild cognitive impairment (aMCI) for the first time. Methods: This was a cross-sectional study. Clinical examinations were performed on all participants. The microbial community of subgingival plaque and the metabolomic profiles of GCF were characterized using the 16S ribosomal RNA (rRNA) gene high-throughput sequencing and liquid chromatography linked to tandem mass spectrometry (LC–MS/MS) analysis, respectively. Results: Thirty-two patients with AD, 32 patients with aMCI, and 32 cognitively normal people were enrolled. The severity of periodontitis was significantly increased in AD patients compared with aMCI patients and cognitively normal people. The 16S rRNA gene sequencing results showed that the relative abundances of 16 species in subgingival plaque were significantly correlated with cognitive function, and LC–MS/MS analysis identified a total of 165 differentially abundant metabolites in GCF. Moreover, multiomics Data Integration Analysis for Biomarker discovery using Latent cOmponents (DIABLO) analysis revealed that 19 differentially abundant metabolites were significantly correlated with Veillonella parvula, Dialister pneumosintes, Leptotrichia buccalis, Pseudoleptotrichia goodfellowii, and Actinomyces massiliensis, in which galactinol, sn-glycerol 3-phosphoethanolamine, D-mannitol, 1 h-indole-1-pentanoic acid, 3-(1-naphthalenylcarbonyl)- and L-iditol yielded satisfactory accuracy for the predictive diagnosis of AD progression. Conclusions: This is the first combined subgingival microbiome and GCF metabolome study in patients with AD and aMCI, which revealed that periodontal microbial dysbiosis and metabolic disorders may be involved in the etiology and progression of AD, and the differential abundance of the microbiota and metabolites may be useful as potential markers for AD in the future. [ABSTRACT FROM AUTHOR]
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- 2024
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27. Heat Stress Responsive Aux/IAA Protein, OsIAA29 Regulates Grain Filling Through OsARF17 Mediated Auxin Signaling Pathway.
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Chen, Zhanghao, Zhou, Wei, Guo, Xianyu, Ling, Sheng, Li, Wang, Wang, Xin, and Yao, Jialing
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CELLULAR signal transduction , *GERMPLASM , *SEED development , *AUXIN , *RICE quality , *HIGH temperatures , *ROOT development - Abstract
High temperature during grain filling considerably reduces yield and quality in rice, but its molecular mechanisms are not fully understood. We investigated the functions of a seed preferentially expressed Aux/IAA gene, OsIAA29, under high temperature-stress in grain filling using CRISPR/Cas9, RNAi, and overexpression. We observed that the osiaa29 had a higher percentage of shrunken and chalkiness seed, as well as lower 1000-grain weight than ZH11 under high temperature. Meanwhile, the expression of OsIAA29 was induced and the IAA content was remarkably reduced in the ZH11 seeds under high temperature. In addition, OsIAA29 may enhance the transcriptional activation activity of OsARF17 through competition with OsIAA21 binding to OsARF17. Finally, chromatin immunoprecipitation quantitative real-time PCR (ChIP-qPCR) results proved that OsARF17 regulated expression of several starch and protein synthesis related genes (like OsPDIL1-1, OsSS1, OsNAC20, OsSBE1, and OsC2H2). Therefore, OsIAA29 regulates seed development in high temperature through competition with OsIAA21 in the binding to OsARF17, mediating auxin signaling pathway in rice. This study provides a theoretical basis and gene resources for auxin signaling and effective molecular design breeding. [ABSTRACT FROM AUTHOR]
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- 2024
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28. Significant Improvement in Soil Organic Carbon Estimation Using Data-Driven Machine Learning Based on Habitat Patches.
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Yu, Wenping, Zhou, Wei, Wang, Ting, Xiao, Jieyun, Peng, Yao, Li, Haoran, and Li, Yuechen
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MACHINE learning , *CARBON in soils , *CARBON cycle , *HABITATS , *DIGITAL soil mapping - Abstract
Soil organic carbon (SOC) is generally thought to act as a carbon sink; however, in areas with high spatial heterogeneity, using a single model to estimate the SOC of the whole study area will greatly reduce the simulation accuracy. The earth surface unit division is important to consider in building different models. Here, we divided the research area into different habitat patches using partitioning around a medoids clustering (PAM) algorithm; then, we built an SOC simulation model using machine learning algorithms. The results showed that three habitat patches were created. The simulation accuracy for Habitat Patch 1 (R2 = 0.55; RMSE = 2.89) and Habitat Patch 3 (R2 = 0.47; RMSE = 3.94) using the XGBoost model was higher than that for the whole study area (R2 = 0.44; RMSE = 4.35); although the R2 increased by 25% and 6.8%, the RMSE decreased by 33.6% and 9.4%, and the field sample points significantly declined by 70% and 74%. The R2 of Habitat Patch 2 using the RF model increased by 17.1%, and the RMSE also decreased by 10.5%; however, the sample points significantly declined by 58%. Therefore, using different models for corresponding patches will significantly increase the SOC simulation accuracy over using one model for the whole study area. This will provide scientific guidance for SOC or soil property monitoring with low field survey costs and high simulation accuracy. [ABSTRACT FROM AUTHOR]
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- 2024
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29. Size Dependence of Gold Nanorods for Efficient and Rapid Photothermal Therapy.
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Zhou, Wei, Yao, Yanhua, Qin, Hailing, Xing, Xiaobo, Li, Zongbao, Ouyang, Min, and Fan, Haihua
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PHOTOTHERMAL effect , *SURFACE plasmon resonance , *NANORODS , *GOLD nanoparticles , *GOLD , *LIVER cells , *ELECTROMAGNETIC coupling - Abstract
In recent years, gold nanomaterials have become a hot topic in photothermal tumor therapy due to their unique surface plasmon resonance characteristics. The effectiveness of photothermal therapy is highly dependent on the shape and size of gold nanoparticles. In this work, we investigate the photothermal therapeutic effects of four different sizes of gold nanorods (GNRs). The results show that the uptake of short GNRs with aspect ratios 3.3–3.5 by cells is higher than that of GNRs with aspect ratios 4–5.5. Using a laser with single pulse energy as low as 28 pJ laser for 20 s can induce the death of liver cancer cells co-cultured with short GNRs. Long GNRs required twice the energy to achieve the same therapeutic effect. The dual-temperature model is used to simulate the photothermal response of intracellular clusters irradiated by a laser. It is found that small GNRs are easier to compact because of their morphological characteristics, and the electromagnetic coupling between GNRs is better, which increases the internal field enhancement, resulting in higher local temperature. Compared with a single GNR, GNR clusters are less dependent on polarization and wavelength, which is more conducive to the flexible selection of excitation laser sources. [ABSTRACT FROM AUTHOR]
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- 2024
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30. CRISPR/Cas9-based toolkit for rapid marker recycling and combinatorial libraries in Komagataella phaffii.
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Zhou, Wei, Li, Yuanyi, Liu, Guosong, Qin, Weichuang, Wei, Dongzhi, Wang, Fengqing, and Gao, Bei
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LYCOPENE , *CRISPRS , *GREEN fluorescent protein , *POST-translational modification , *GENOME editing , *SACCHAROMYCES cerevisiae - Abstract
Komagataella phaffii, a nonconventional yeast, is increasingly attractive to researchers owing to its posttranslational modification ability, strict methanol regulatory mechanism, and lack of Crabtree effect. Although CRISPR-based gene editing systems have been established in K. phaffii, there are still some inadequacies compared to the model organism Saccharomyces cerevisiae. In this study, a redesigned gRNA plasmid carrying red and green fluorescent proteins facilitated plasmid construction and marker recycling, respectively, making marker recycling more convenient and reliable. Subsequently, based on the knockdown of Ku70 and DNA ligase IV, we experimented with integrating multiple DNA fragments at a single locus. A 26.5-kb-long DNA fragment divided into 11 expression cassettes for lycopene synthesis could be successfully integrated into a single locus at one time with a success rate of 57%. A 27-kb-long DNA fragment could also be precisely knocked out with a 50% positive rate in K. phaffii by introducing two DSBs simultaneously. Finally, to explore the feasibility of rapidly balancing the expression intensity of multiple genes in a metabolic pathway, a yeast combinatorial library was successfully constructed in K. phaffii using lycopene as an indicator, and an optimal combination of the metabolic pathway was identified by screening, with a yield titer of up to 182.73 mg/L in shake flask fermentation. Key points: • Rapid marker recycling based on the visualization of a green fluorescent protein • One-step multifragment integration and large fragment knockout in the genome • A random assembly of multiple DNA elements to create yeast libraries in K. phaffii [ABSTRACT FROM AUTHOR]
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- 2024
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31. Development of large-flux laminated methanol reforming microreactor heated by methanol catalytic combustion.
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Zhong, Yuchen, Zhou, Wei, Zhou, Shupan, Li, Xinying, Chu, Xuyang, and Wu, Linjing
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METHANOL as fuel , *METHANOL , *COMBUSTION , *STEAM reforming , *DEIONIZATION of water , *HYDROGEN production - Abstract
To achieve high flow hydrogen production, a laminated self-thermal methanol reforming microreactor was designed. Through simulation and experiments, the hydrogen production performance of the microreactor and the compatibility between the methanol catalytic combustion module and the methanol steam reforming module were investigated. The results show that the microreactor exhibits impressive hydrogen production performance, with a methanol conversion rate of 95.27%. When the inlet flow rate of the mixture of methanol and deionized water was increased to a high flow rate, the microreactor exhibits significant cold spots over a wide range in the reaction chamber plates, which could be effectively solved by enhancing the methanol catalytic combustion intensity. The methanol catalytic combustion module inside the microreactor can meet the heat demand of the methanol reforming module. The microreactor operated for 20 h with a methanol-deionized water mixture inlet flow rate of 12 mL/min and a methanol inlet flow rate of 7.5 mL/min; the methanol conversion rate finally stabilized at 90.1%, which was decreased by about 2.2% compared with the initial methanol conversion rate. • Laminated self-thermal methanol steam reforming microreactor was designed with a maximum hydrogen flow rate of 10 L/min. • Thermal matching of methanol catalytic combustion reaction and methanol reforming reaction gained explored. • Methanol conversion rate was improved from 58.6% to 91.2% at the inlet flow rate of methanol of 7.5 mL/min. [ABSTRACT FROM AUTHOR]
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- 2024
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32. Study on mechanism of Atractylodes macrocephala in regulating oxidative stress based on network pharmacology and molecular docking.
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WANG Xue-feng, ZHOU Wei-wei, ZHANG Meng-jie, FU Hong-yun, ZHENG Wei, and LI Xiu-mei
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MOLECULAR docking , *MOLECULAR pharmacology , *OXIDATIVE stress , *DATABASES , *CELLULAR signal transduction - Abstract
The study was based on network pharmacology and molecular docking techniques, and investigated the active components and mechanisms through which Atractylodes macrocephala regulates oxidative stress. Active components and target proteins of Atractylodes macrocephala were screened from the TCMSP database, while oxidative stress-related targets were obtained from GeneCards and OMIM databases. Using STRING 11.5 platform and Cytoscape 3.7.2 software, a network of Atractylodes macrocephala-components-targets and a PPI network were constructed, and core targets were identified. The DAVID database was utilized for GO and KEGG pathway enrichment analysis. Molecular docking using AutoDockTools software examined the binding efficacy of active components with core targets. The results showed six main active components, including 12-kirenol acyl-8-epi-heliangolide, 14-acetyl-12-kirenol acyl-8-epi-heliangolide, α-amyrin, β-sitosterol, 3β-acetoxyatractylone, and 8β-ethoxyhirsutinolide, along with 133 key targets. GO functional enrichment yielded 460 terms, and KEGG pathway annotation identified 127 signaling pathways, including TNF, AGERAGE, IL-17, and PI3K-Akt pathways. Molecular docking results demonstrated favorable binding activity between Atractylodes macrocephala active components and core targets, with α-amyrin showing the highest binding ALB, EGFR, MAPK1, NQO1, and PTGS2. The study indicates that Atractylodes macrocephala may exert its antioxidant effects by regulating signaling pathways such as TNF, AGE-RAGE, IL-17, PI3K-Akt, and oxidative stress-related targets. [ABSTRACT FROM AUTHOR]
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- 2024
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33. Machine Learning-Based Breast Tumor Ultrasound Radiomics for Pre-operative Prediction of Axillary Sentinel Lymph Node Metastasis Burden in Early-Stage Invasive Breast Cancer.
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Yao, Jiejie, Zhou, Wei, Xu, Shangyan, Jia, Xiaohong, Zhou, Jianqiao, Chen, Xiaosong, and Zhan, Weiwei
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SENTINEL lymph nodes , *LYMPHATIC metastasis , *RADIOMICS , *CANCER invasiveness , *BREAST ultrasound , *SURGICAL education , *MICROMETASTASIS ,AGE factors in cancer - Abstract
The aim of the work described here was to assess the application of ultrasound (US) radiomics with machine learning (ML) classifiers to the prediction of axillary sentinel lymph node metastasis (SLNM) burden in early-stage invasive breast cancer (IBC). In this study, 278 early-stage IBC patients with at least one SLNM (195 in the training set and 83 in the test set) were studied at our institution. Pathologic SLNM burden was used as the reference standard. The US radiomics features of breast tumors were extracted by using 3D-Slicer and PyRadiomics software. Four ML classifiers—linear discriminant analysis (LDA), support vector machine (SVM), random forest (RF) and decision tree (DT)—were used to construct radiomics models for the prediction of SLNM burden. The combined clinicopathologic–radiomics models were also assessed with respect to sensitivity, specificity, accuracy and areas under the curve (AUCs). Among the US radiomics models, the SVM classifier achieved better predictive performance with an AUC of 0.920 compared with RF (AUC = 0.874), LDA (AUC = 0.835) and DT (AUC = 0.800) in the test set. The clinicopathologic model had low efficacy, with AUCs of 0.678 and 0.710 in the training and test sets, respectively. The combined clinicopathologic (C) factors and SVM classifier (C + SVM) model improved the predictive ability with an AUC of 0.934, sensitivity of 86.7%, specificity of 89.9% and accuracy of 91.0% in the test set. ML-based US radiomics analysis, as a novel and promising predictive tool, is conducive to a precise clinical treatment strategy. [ABSTRACT FROM AUTHOR]
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- 2024
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34. Integrative Multi-Omics Analysis Identifies Transmembrane p24 Trafficking Protein 1 (TMED1) as a Potential Prognostic Marker in Colorectal Cancer.
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Guo, Xin, Zhou, Wei, Jin, Jinmei, Lin, Jiayi, Zhang, Weidong, Zhang, Lijun, and Luan, Xin
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COLORECTAL cancer , *PROGNOSIS , *DRUG resistance in cancer cells , *MULTIOMICS , *REGULATORY T cells , *ONCOGENES - Abstract
Simple Summary: In this study, the expression and prognostic significance of the transmembrane p24 trafficking protein 1 (TMED1) in colorectal cancer were investigated by utilizing patient survival data and multi-omics datasets, including immunohistochemical staining, transcriptomics, and proteomics. The results indicated that TMED1, functioning as an oncogene, is upregulated in colorectal cancer and exhibits a significant association with an unfavorable prognosis. Furthermore, the downregulation of TMED1 was found to impact the cell cycle and apoptotic signaling pathways. Additionally, a positive correlation was identified between TMED1 and other members of the TMED family (TMED2, TMED4, TMED9, and TMED10) in colorectal cancer. The protein–protein interaction network analysis further indicated the potential influence of TMED1 on immune regulation. Consequently, TMED1 emerged as a promising candidate biomarker for assessing the progression and prognosis of colorectal cancer. Several TMED protein family members are overexpressed in malignant tumors and associated with tumor progression. TMED1 belongs to the TMED protein family and is involved in protein vesicular trafficking. However, the expression level and biological role of TMED1 in colorectal cancer (CRC) have yet to be fully elucidated. In this study, the integration of patient survival and multi-omics data (immunohistochemical staining, transcriptomics, and proteomics) revealed that the highly expressed TMED1 was related to the poor prognosis in CRC. Crystal violet staining indicated the cell growth was reduced after knocking down TMED1. Moreover, the flow cytometry results showed that TMED1 knockdown could increase cell apoptosis. The expression of TMED1 was positively correlated with other TMED family members (TMED2, TMED4, TMED9, and TMED10) in CRC, and the protein–protein interaction network suggested its potential impact on immune regulation. Furthermore, TMED1 expression was positively associated with the infiltration levels of regulatory T cells (Tregs), cancer-associated fibroblasts (CAFs), and endothelial cells and negatively correlated with the infiltration levels of CD4+ T cells, CD8+ T cells, and B cells. At last, the CTRP and GDSC datasets on the GSCA platform were used to analyze the relationship between TMED1 expression and drug sensitivity (IC50). The result found that the elevation of TMED1 was positively correlated with IC50 and implied it could increase the drug resistance of cancer cells. This research revealed that TMED1 is a novel prognostic biomarker in CRC and provided a valuable strategy for analyzing potential therapeutic targets of malignant tumors. [ABSTRACT FROM AUTHOR]
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- 2024
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35. Transpalpebral electrical stimulation for the treatment of retinitis pigmentosa: study protocol for a series of N-of-1 single-blind, randomized controlled trial.
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Zhou, Wei, Huang, Ziyang, Xu, Kai, Li, Yamin, Li, Xiaoyu, Li, Jiaxian, Jin, Yu, Snellingen, Torkel, and Liang, Lina
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ELECTRIC stimulation , *RETINITIS pigmentosa , *MACULAR degeneration , *RESEARCH protocols , *OPTICAL coherence tomography , *VISION - Abstract
Background: Retinitis pigmentosa (RP) is an inherited disease characterized by a progressive loss of rod photoreceptors of the eye, leading to irreversible blindness. To date, to our knowledge, no clinical prospective studies have been undertaken that could document the effect of interventions that could reverse or reduce the progression of this disease. The application of microcurrent stimulation (ES) of the eye in the treatment of chronic eye diseases such as glaucoma and age-related macular degeneration has been used over several decades and has been reported to have beneficial effects to reduce the progression of these blinding diseases and has been supported by animal studies and smaller clinical studies, but to date, no large randomized clinical trials on the use of microcurrent therapy have been published. More recent clinical reports have also shown beneficial effects of ES on slowing the progression of RP but also lacks data from robust prospective clinical outcome studies. To our knowledge, this is the first prospective randomized study to evaluate the safety and clinical effectiveness of transpalpebral electrical stimulation (TpES) on the progression of RP. Methods: Randomized prospective study using N-of-1 trial 3 single-blind, crossover comparisons. The intervention period of each comparison is divided into treatment period and control period which are randomized arranged. Twelve participants will be strictly recruited in N-of-1 trial by the researcher in accordance with the inclusion and exclusion criteria. The main outcome of interest examined after each cycle of the 8-week intervention period is the assessment of the visual field (VF). Other variables of interest are best corrected visual acuity (BCVA), retinal function using electroretinogram (ERG), and visual function using NEI VFQ-25 questionnaire. Objective assessments of retinal changes will be undertaken using optical coherence tomography (OCT) and fundus autofluorescence (FAF). Discussion: The trial will evaluate the efficacy and safety of microcurrent stimulation on RP and provide high-quality evidence for clinical application through N-of-1 trial. Trial registration: Chinese Clinical Trial Registry; ChiCTR2300067357; https://www.chictr.org.cn/showproj.html?proj=174635. Registered on 5 January 2023 [ABSTRACT FROM AUTHOR]
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- 2024
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36. A novel AML1-ETO/FTO positive feedback loop promotes leukemogenesis and Ara-C resistance via stabilizing IGFBP2 in t(8;21) acute myeloid leukemia.
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Zhou, Wei, Li, Siying, Wang, Hong, Zhou, Jingfeng, Li, Shuyi, Chen, Guofeng, Guan, Wei, Fu, Xianli, Nervi, Clara, Yu, Li, and Li, Yonghui
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ACUTE myeloid leukemia , *PRELEUKEMIA , *GENE expression , *ACTIVATED protein C resistance , *CYTARABINE , *PATIENT experience , *CHIMERIC proteins , *RNA sequencing , *AZACITIDINE - Abstract
Background: t(8;21)(q22;q22) is one of the most frequent chromosomal abnormalities in acute myeloid leukemia (AML), leading to the generation of the fusion protein AML1-ETO. Despite t(8;21) AML being considered as a subtype with a favorable prognosis, approximately 30–50% of patients experience drug resistance and subsequent relapse. N6-methyladenosine (m6A) is demonstrated to be involved in the development of AML. However, the regulatory mechanisms between AML1-ETO and m6A-related enzymes and the roles of dysregulated m6A modifications in the t(8;21)-leukemogenesis and chemoresistance remain elusive. Methods: Chromatin immunoprecipitation, dual-luciferase reporter assay, m6A-qPCR, RNA immunoprecipitation, and RNA stability assay were used to investigate a regulatory loop between AML1-ETO and FTO, an m6A demethylase. Gain- and loss-of-function experiments both in vitro and in vivo were further performed. Transcriptome-wide RNA sequencing and m6A sequencing were conducted to identify the potential targets of FTO. Results: Here we show that FTO is highly expressed in t(8;21) AML, especially in patients with primary refractory disease. The expression of FTO is positively correlated with AML1-ETO, which is attributed to a positive regulatory loop between the AML1-ETO and FTO. Mechanistically, AML1-ETO upregulates FTO expression through inhibiting the transcriptional repression of FTO mediated by PU.1. Meanwhile, FTO promotes the expression of AML1-ETO by inhibiting YTHDF2-mediated AML1-ETO mRNA decay. Inactivation of FTO significantly suppresses cell proliferation, promotes cell differentiation and renders resistant t(8;21) AML cells sensitive to Ara-C. FTO exerts functions by regulating its mRNA targets, especially IGFBP2, in an m6A-dependent manner. Regain of Ara-C tolerance is observed when IGFBP2 is overexpressed in FTO-knockdown t(8;21) AML cells. Conclusion: Our work reveals a therapeutic potential of targeting AML1-ETO/FTO/IGFBP2 minicircuitry in the treatment for t(8;21) patients with resistance to Ara-C. [ABSTRACT FROM AUTHOR]
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- 2024
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37. PdMo bimetallene nanozymes for photothermally enhanced antibacterial therapy and accelerated wound healing.
- Author
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Zhou, Wei, Li, Na, Wang, Minghui, Wu, Peixian, Fu, Qian, Wang, Wenjie, Liu, Zheng, He, Shuiyuan, Zhou, MengYu, Song, Dan, Chen, Jie, Lin, Nanyun, Wu, Yingying, Jiao, Lei, Tan, Xiaofeng, and Yang, Qinglai
- Subjects
- *
WOUND healing , *SYNTHETIC enzymes , *REACTIVE oxygen species , *HYDROXYL group , *HYDROGEN peroxide , *MEMBRANE permeability (Biology) - Abstract
Although antibacterial platforms involving nanozymes have been extensively investigated, there are still problems of poor reactive oxygen species generation efficiency and obstinate bacterial biofilms. Developing a nanozyme-photothermal therapy nanoplatform with superior sterilization effects and minimal side effects would be a good alternative for completely eliminating bacteria and biofilms. Herein, an ultrathin PdMo bimetallene nanozyme with a planar topology and boosted metal utilization, exhibiting excellent photothermal and peroxidase-like activity, is designed for synergistic nanozyme-photothermal sterilization applications and accelerated wound healing. The superior catalytic activity of PdMo bimetallene nanozymes could convert a biosafe concentration of hydrogen peroxide (H2O2) into large quantities of toxic hydroxyl radicals (•OH) under laser irradiation, enhancing bacterial membrane permeability and thermal sensitivity for efficient removal of bacteria and biofilms. In addition, PdMo bimetallene presents a good wound-healing ability according to the results of fibroblast proliferation and collagen deposition with minor side effects. This work would provide an innovative avenue for developing metallene-based nanozymes for biomedical applications. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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38. All-organic arrayed photodetectors with fast UVA–UVC response based on self-aligned planar BPEA nanowires.
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Zhou, Wei, Wang, Xingyu, Li, Yajun, Liu, Hanyu, Huang, Pingyang, Chen, Xiangtao, and Xu, Jinyou
- Subjects
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PHOTODETECTORS , *NANOWIRES , *RESPONSIVITY (Detectors) , *NANOWIRE devices , *RADIATION absorption , *HYDROPHOBIC interactions - Abstract
Single-crystalline 9,10-bis(phenylethynyl)anthracene (BPEA) nanowires are promising building blocks for all-organic ultraviolet (UV) photodetectors owing to their environmental stability and efficient absorption of UV radiation. However, many of the intrinsic properties of BPEA nanowires become largely smeared when they adopt disordered ensembles. In this study, by exploiting the exceptional graphoepitaxial effect of hydrophobic parallel nanogrooves, self-aligned planar BPEA nanowires with high crystallinity and chemical purity are grown over the entire sapphire surface. They are then integrated in situ to form arrayed photodetectors by direct deposition of metal electrodes. This strategy helps preserve the exceptional properties of single-crystalline BPEA nanowires to improve photoresponse performance, as unwanted structural damage and chemical impurities associated with the demanding post-growth transfer and alignment steps can be eliminated. Under ambient conditions, these photodetectors exhibit fast and sensitive photoresponse to UV radiation in the 200–400 nm range, covering the short-wave UV (UVC), the middle-wave UV (UVB), and the long-wave UV (UVA) bands. The arrayed photodetectors also enable statistical testing and evaluation of their performance, a prerequisite for advancing nanowire devices into real-world applications. Averaging over 81 detectors gives a responsivity of 0.30 A/W, a detectivity of 3.11 × 109 Jones, and a response time of 31.0 ms under 380 nm light at 20.32 mW/cm2 and 20-V bias. The proposed methods for the rational growth of aligned nanowires and scaled-up production of photodetectors represent a substantial advance toward the implementation of UV photodetectors from organic molecules. [ABSTRACT FROM AUTHOR]
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- 2024
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- View/download PDF
39. Noninvasive electrical stimulation as a neuroprotective strategy in retinal diseases: a systematic review of preclinical studies.
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Li, Jiaxian, Zhou, Wei, Liang, Lina, Li, Yamin, Xu, Kai, Li, Xiaoyu, Huang, Ziyang, and Jin, Yu
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- *
ELECTRIC stimulation , *RETINAL diseases , *RETINITIS pigmentosa , *RETINAL degeneration , *RETINAL injuries , *ELECTRICAL injuries , *VISION , *NEUROTROPHIN receptors , *RETINAL blood vessels - Abstract
Background: Electrical activity has a crucial impact on the development and survival of neurons. Numerous recent studies have shown that noninvasive electrical stimulation (NES) has neuroprotective action in various retinal disorders. Objective: To systematically review the literature on in vivo studies and provide a comprehensive summary of the neuroprotective action and the mechanisms of NES on retinal disorders. Methods: Based on the PRISMA guideline, a systematic review was conducted in PubMed, Web of Science, Embase, Scopus and Cochrane Library to collect all relevant in vivo studies on "the role of NES on retinal diseases" published up until September 2023. Possible biases were identified with the adopted SYRCLE's tool. Results: Of the 791 initially gathered studies, 21 articles met inclusion/exclusion criteria for full-text review. The results revealed the neuroprotective effect of NES (involved whole-eye, transcorneal, transscleral, transpalpebral, transorbital electrical stimulation) on different retinal diseases, including retinitis pigmentosa, retinal degeneration, high-intraocular pressure injury, traumatic optic neuropathy, nonarteritic ischemic optic neuropathy. NES could effectively delay degeneration and apoptosis of retinal neurons, preserve retinal structure and visual function with high security, and its mechanism of action might be related to promoting the secretion of neurotrophins and growth factors, decreasing inflammation, inhibiting apoptosis. The quality scores of included studies ranged from 5 to 8 points (a total of 10 points), according to SYRCLE's risk of bias tool. Conclusion: This systematic review indicated that NES exerts neuroprotective effects on retinal disease models mainly through its neurotrophic, anti-inflammatory, and anti-apoptotic capabilities. To assess the efficacy of NES in a therapeutic setting, however, well-designed clinical trials are required in the future. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
- View/download PDF
40. CRISPR/Cas9-based toolkit for rapid marker recycling and combinatorial libraries in Komagataella phaffii.
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Zhou, Wei, Li, Yuanyi, Liu, Guosong, Qin, Weichuang, Wei, Dongzhi, Wang, Fengqing, and Gao, Bei
- Abstract
Komagataella phaffii, a nonconventional yeast, is increasingly attractive to researchers owing to its posttranslational modification ability, strict methanol regulatory mechanism, and lack of Crabtree effect. Although CRISPR-based gene editing systems have been established in K. phaffii, there are still some inadequacies compared to the model organism Saccharomyces cerevisiae. In this study, a redesigned gRNA plasmid carrying red and green fluorescent proteins facilitated plasmid construction and marker recycling, respectively, making marker recycling more convenient and reliable. Subsequently, based on the knockdown of Ku70 and DNA ligase IV, we experimented with integrating multiple DNA fragments at a single locus. A 26.5-kb-long DNA fragment divided into 11 expression cassettes for lycopene synthesis could be successfully integrated into a single locus at one time with a success rate of 57%. A 27-kb-long DNA fragment could also be precisely knocked out with a 50% positive rate in K. phaffii by introducing two DSBs simultaneously. Finally, to explore the feasibility of rapidly balancing the expression intensity of multiple genes in a metabolic pathway, a yeast combinatorial library was successfully constructed in K. phaffii using lycopene as an indicator, and an optimal combination of the metabolic pathway was identified by screening, with a yield titer of up to 182.73 mg/L in shake flask fermentation. Key points: • Rapid marker recycling based on the visualization of a green fluorescent protein • One-step multifragment integration and large fragment knockout in the genome • A random assembly of multiple DNA elements to create yeast libraries in K. phaffii [ABSTRACT FROM AUTHOR]
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- 2024
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41. The impact of the Russia-Ukraine conflict on the extreme risk spillovers between agricultural futures and spots.
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Zhou, Wei-Xing, Dai, Yun-Shi, Duong, Kiet Tuan, and Dai, Peng-Fei
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RUSSIAN invasion of Ukraine, 2022- , *RUSSIA-Ukraine Conflict, 2014- , *AGRICULTURE , *FUTURES market , *AGRICULTURAL marketing - Abstract
The ongoing Russia-Ukraine conflict between two major agricultural powers has posed significant threats and challenges to the global food system and world food security. Focusing on the impact of the conflict on the global agricultural market, we propose a new analytical framework for tail dependence, and combine the Copula-CoVaR method with the ARMA-GARCH-skewed Student-t model to examine the tail dependence structure and extreme risk spillover between agricultural futures and spots over the pre- and post-outbreak periods. Our results indicate that the tail dependence structures in the futures-spot markets of soybean, maize, wheat, and rice have all reacted to the Russia-Ukraine conflict. Furthermore, the outbreak of the conflict has intensified risks of the four agricultural markets in varying degrees, with the wheat market being affected the most. Additionally, all the agricultural futures markets exhibit significant downside and upside risk spillovers to their corresponding spot markets before and after the outbreak of the conflict, whereas the strengths of these extreme risk spillover effects demonstrate significant asymmetries at the directional (downside versus upside) and temporal (pre-outbreak versus post-outbreak) levels. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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42. Identification of forest fire points under clear sky conditions with Himawari-8 satellite data.
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Zhou, Wei, Tang, Bo-Hui, He, Zhi-Wei, Huang, Liang, and Chen, Junyi
- Subjects
- *
FOREST fires , *FOREST fire prevention & control , *RANDOM forest algorithms , *FOREST monitoring , *WILDFIRE prevention , *NATURAL disasters , *ZENITH distance - Abstract
Since forest fire is one of the most dangerous natural disasters and presents serious threats to the local ecological environment, economic growth, and public safety, it is essential to carry out accurate and real-time forest fire monitoring. In this study, a forest fire monitoring method that combines a threshold-based algorithm and random forest (RF) model using Himawari-8 data is proposed. The threshold-based algorithm employs the solar zenith angle to adaptively determine the potential fire point judgement threshold to extract possible fire points. The RF model constructed with spectral features and spatio-temporal information is subsequently utilized to eliminate pseudo-fire points from the results of the threshold-based algorithm. To eliminate fire points in non-forest areas, post-processing is performed using land cover data. Five fire occurrence moments in the research area are selected to verify the identification accuracy. The results reveal that the overall accuracy and the overall comprehensive evaluation values are 97.36% and 0.913, respectively, which demonstrates that the proposed method is capable of accurately identifying forest fire points and providing an effective means for forest fire monitoring. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
43. An analytical complete model of root pressure generation: Theoretical bases for studying hydraulics of bamboo.
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Yang, Dongmei, Zhou, Wei, Wang, Xiaolin, Zhao, Mei, Zhang, Yong‐Jiang, Tyree, Melvin T., and Peng, Guoquan
- Subjects
- *
HYDRAULICS , *GRAVITATIONAL potential , *WATER distribution , *PLANT-water relationships , *SOIL moisture , *BAMBOO - Abstract
To better understand the dynamics and functional roles of root pressure, we represent a novel and the first complete analytical model for root pressure, which can be applied to complex roots/shoots. The osmotic volume of a single root is equal to that of the vessel lumen in fine roots and adjacent apoplastic spaces. Water uptake occurs via passive osmosis and active solute uptake (Js*, osmol s−1), resulting in the osmolyte concentration Cr (mol·kg−1 of water) at a fixed osmotic volume. Solute loss occurs via two passive processes: radial diffusion of solute Km (Cr− Csoil) from fine roots to soil, where Km is the diffusional constant and Csoil is the soil–solute concentration, and the mass flow of solute and water into the plant from the fine roots. The proposed model predicts the quadratic function of root pressure (Pr), Pr2+bPr+c=0, where b and c are the functions of plant hydraulic resistance, soil water potential, solute flux and gravitational potential. The model demonstrates the root pressure‐mediated distribution of water through the hydraulic architecture of a 6.8‐m‐tall bamboo shoot. This model provides a theoretical basis to test the functional roles of root pressure in shaping the hydraulic architecture and refilling potential xylem embolisms. Summary statement: An analytical solution for root pressure is derived and illustrated by applying it to the measured hydraulic architecture of a 7‐m bamboo shoot. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
44. DR-CIML: Few-shot Object Detection via Base Data Resampling and Cross-iteration Metric Learning.
- Author
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Cao, Guoping, Zhou, Wei, Yang, Xudong, Zhu, Feijia, and Chai, Lin
- Abstract
Aiming at the problems of difficult data collection and labor-intensive manual annotation, few-shot object detection (FSOD) has gained wide attention. Although current transfer-learning-based detection methods outperform meta-learning-based methods, their data organization fails to fully utilize the diversity of the source domain data. In view of this, Data Resampling (DR) organization is proposed to fine-tune the network, which can be employed as a component of any model and dataset without additional inference overhead. In addition, in order to improve the generalization of the model, a Cross-Iteration Metric-Learning (CIML) branch is embedded in the few-shot object detector, thus actively improving intra-category feature propinquity and inter-category feature discrimination. Our generic DR-CIML approach obtained competitive scores in extensive comparative experiments. The nAP50 performance on PASCAL VOC improved by up to 6.3 points, and the bAP50 performance reached 81.0, surpassing the base stage model (80.8) for the first time. The nAP75 performance on MS COCO improved by up to 1.6 points. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
45. TFEB SUMOylation in macrophages accelerates atherosclerosis by promoting the formation of foam cells through inhibiting lysosomal activity.
- Author
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Wang, Kezhou, Zhou, Wei, Hu, Gaolei, Wang, Lifeng, Cai, Rong, and Tian, Tian
- Abstract
Atherosclerosis (AS) is a serious cardiovascular disease. One of its hallmarks is hyperlipidemia. Inhibiting the formation of macrophage foam cells is critical for alleviating AS. Transcription factor EB (TFEB) can limit the formation of macrophage foam cells by upregulating lysosomal activity. We examined whether TFEB SUMOylation is involved in this progress during AS. In this study, we investigated the role of TFEB SUMOylation in macrophages in AS using TFEB SUMOylation deficiency Ldlr−/− (TFEB-KR: Ldlr−/−) transgenic mice and TFEB-KR bone marrow-derived macrophages. We observed that TFEB-KR: Ldlr−/− atherosclerotic mice had thinner plaques and macrophages with higher lysosomal activity when compared to WT: Ldlr−/− mice. TFEB SUMOylation in macrophages decreased after oxidized low-density lipoprotein (OxLDL) treatment in vitro. Compared with wild type macrophages, TFEB-KR macrophages exhibited less lipid deposition after OxLDL treatment. Our study demonstrated that in AS, deSUMOylation of TFEB could inhibit the formation of macrophage foam cells through enhancing lysosomal biogenesis and autophagy, further reducing the accumulation of lipids in macrophages, and ultimately alleviating the development of AS. Thus, TFEB SUMOylation can be a switch to modulate macrophage foam cells formation and used as a potential target for AS therapy. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
46. All-in-one self-floating porous foams as robust heat-blocking layers for efficient photothermal conversion and solar desalination.
- Author
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Ren, Liping, Zhou, Wei, Wang, Lei, Lin, Kuo, Xu, Yachao, Wu, Jiaxing, Xie, Ying, and Fu, Honggang
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FOAM , *PHOTOTHERMAL effect , *PHOTOTHERMAL conversion , *SURFACE plasmon resonance , *SOLAR energy conversion , *AMORPHOUS carbon , *THERMAL conductivity - Abstract
Self-floating all-in-one photothermal evaporators are fabricated by freeze-drying, casting, and surface-hydrogenation, in which the hydrophilic black TiO 2 provides a path for water molecules, Ag nanoparticles act as local heating points, and amorphous carbon improves locally thermal conductivity and blocks thermal loss. These photothermal evaporators exhibit high-efficiency solar steam generation and desalination. [Display omitted] Solar-driven interfacial evaporation is a highly efficient and ecofriendly technology for producing freshwater. Herein, self-floating plasmon Ag/black TiO 2 /carbon porous layered foams (Ag-BTCFs) were demonstrated as efficient solar-thermal convectors using freeze-drying cast-molding and high-temperature surface hydrogenation strategies. This all-in-one three-dimensional (3D) cross-linked self-floating porous layered foam material with full-spectrum absorption can fully harvest sunlight (∼95.45%) and effectively block heat transfer to its sublayer. The synergy of sufficient utilization of absorbed ultraviolet radiation by black TiO 2 (b-TiO 2), visible light absorption by Ag nanoparticles (Ag NPs) via localized surface plasmon resonance, and near-infrared absorption by layered-amorphous carbon can achieve full-solar-spectrum absorption to concentrate thermal energy. In addition to their synergistic effect, they are conducive to the relaxation of hot electrons when utilizing photogenerated holes to degrade pollutants in domestic wastewater. The steam generation efficiency of Ag-BTCFs is up to 1.79 kg m−2 h−1 due to their solar energy conversion efficiency of 81.74% under 1 sun irradiation, which is five times higher than the evaporation rate of pure water. Notably, the material's efficient ion removal rate of 99.80% for solar desalination indicates its high potential for various applications. This strategy provides new insights for fabricating recyclable heat-blocking layer systems against thermal loss to enhance solar steam generation. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
47. Study on the heat input regulation mechanism of compound excitation device and its influence on arc shape and penetration behavior in GTAW.
- Author
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Zhou, Wei, Yue, Jianfeng, Zhong, Pu, Chen, Haojie, and Zhou, Hao
- Abstract
In order to realize the heat input regulation in the gas tungsten arc welding (GTAW) process, a novel compound excitation device consisting of a longitudinal magnetic field and a cusp magnetic field was developed in this paper. The magnetic field distribution law in the arc zone was analyzed under various excitation parameters of the device. Using 316L austenitic stainless steel as the base metal, the variation law of arc and weld penetration under different coupling excitation parameters was studied. The research reveals that the magnetic induction intensity in arc zone approximately conforms to the linear superposition law of two single magnetic fields. Under the compound excitation device, the welding arc is compressed while maintaining its deflection, causing its cross-section to change from circular to elliptical. Under the premise that the longitudinal excitation current maintains the arc deflection angle, an increase in cusp excitation current results in a decrease in weld width and arc bottom area, while increasing weld penetration, metal melting area, and arc voltage. These results indicate that the compound excitation device can effectively regulate the heat input distribution and arc heat flux density. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
48. Low‐Cost Preparation of High‐Performance Na‐B‐H‐S Electrolyte for All‐Solid‐State Sodium‐Ion Batteries.
- Author
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Zhou, Wei, Song, Changsheng, Li, Shuyang, Liu, Miao, He, Huiwen, Yang, Shaoyu, Xie, Jin, Wang, Fei, Fang, Fang, Sun, Dalin, Zhao, Jie, and Song, Yun
- Subjects
- *
LITHIUM-ion batteries , *ELECTROLYTES , *SODIUM ions , *ELECTRIC batteries , *SUPERIONIC conductors , *SODIUM borohydride , *RAW materials , *FLUOROETHYLENE - Abstract
All‐solid‐state sodium‐ion batteries have the potential to improve safety and mitigate the cost bottlenecks of the current lithium‐ion battery system if a high‐performance electrolyte with cost advantages can be easily synthesized. In this study, a one‐step dehydrogenation‐assisted strategy to synthesize the novel thio‐borohydride (Na‐B‐H‐S) electrolyte is proposed, in which both raw material cost and preparation temperature are significantly reduced. By using sodium borohydride (NaBH4) instead of B as a starting material, B atoms can be readily released from NaBH4 with much less energy and thus became more available to generate thio‐borohydride. The synthesized Na‐B‐H‐S (NaBH4/Na‐B‐S) electrolyte exhibits excellent compatibility with current cathode materials, including FeF3 (1.0–4.5 V), Na3V2(PO4)3 (2.0–4.0 V), and S (1.2–2.8 V). This novel Na‐B‐H‐S electrolyte will take a place in mainstream electrolytes because of its advantages in preparation, cost, and compatibility with various cathode materials. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
49. Novel disulfide functionalized nitrogen-rich covalent organic polymer for efficient and recyclable adsorption of Au(III).
- Author
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Peng, Lin-Ling, Zhou, Wei-Fang, Chen, Min, Li, Li-Jun, Liu, Yu, Zhou, Cong-Shan, Xie, Jun, and Tang, Ke-Wen
- Subjects
- *
ADSORPTION (Chemistry) , *DISULFIDES , *POLYMERS , *X-ray diffraction , *AQUEOUS solutions - Abstract
A novel disulfide functionalized nitrogen-rich covalent organic polymer (S-COP) directly synthesized by a solvothermal method were characterized by XRD, SEM, FT-IR, N2 adsorption–desorption and XPS techniques. The as-synthesized polymer shows efficient adsorption performance for Au(III) from aqueous solution. The adsorption equilibrium of the adsorbent could be achieved within 5 h, and the as-synthesized S-COP exhibits an exceedingly high Au(III) uptake capacity of 1506 mg·g−1. Furthermore, S-COP has satisfactory selectivity and reusability, which is a highlight of adsorption materials. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
50. The association between blood pressure at admission and in-hospital mortality in patients with subarachnoid hemorrhage.
- Author
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Zhou, Wei and He, Yi
- Subjects
- *
HOSPITAL mortality , *SUBARACHNOID hemorrhage , *BLOOD pressure , *PROPORTIONAL hazards models , *OLDER patients - Abstract
Purpose: The objective of this study was to examine the association between mean arterial pressure (MAP) at admission and in-hospital mortality among patients diagnosed with subarachnoid hemorrhage (SAH). Methods: In this cohort study, 1420 SAH patients were categorized into four groups based on quartiles of MAP: <82 mmHg group, 82–93 mmHg group, 93–103 mmHg group, and >103 mmHg group. Furthermore, the X-tile program was used to divide all patients into four groups: < 81.7 mmHg group, 81.7–92.3 mmHg group, 92.3–103.7 mmHg group, and > 103.7 mmHg group. The association between MAP and in-hospital mortality of SAH patients was evaluated using univariate and multivariable Cox proportional hazards models. A restricted cubic spline (RCS) was plotted to explore the association between MAP at admission and in-hospital mortality in patients with SAH. Results: The median follow-up duration was 7.87 days, during which, 1219 (85.85%) patients survived. After adjusting for confounding factors, MAP <82 mmHg (hazard ratio (HR)=1.67, 95% confidence interval (CI): 1.08–2.57) or MAP >103 mmHg (HR=2.13, 95% CI: 1.38–3.29) was associated with increased risk of in-hospital mortality of SAH patients. Subgroup analysis depicted that MAP <82 mmHg or MAP >103 mmHg was associated with increased risk of in-hospital mortality in male patients or those aged ≥ 65 years. MAP >103 mmHg was linked with elevated risk of in-hospital mortality in patients aged <65 years; individuals with normal and underweight, overweight, and obesity; or people with hypertension. Conclusion: The findings may offer a preliminary estimate of the optimum range for SAH patients for future randomized trials. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
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