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A Meta-Analysis of the Prognostic and Clinicopathological Significance of circZFR in Human Gastrointestinal Cancers 被引量:1
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作者 Christian Cedric Bongolo Erick Thokerunga +1 位作者 yu zhang Jian-Cheng Tu 《International Journal of Clinical Medicine》 CAS 2024年第3期134-144,共11页
Background: Studies of gastrointestinal (GIT) cancers have shown that circZFR could be involved in the development and progression of various GIT cancers. However, small sample sizes limit the clinical significance of... Background: Studies of gastrointestinal (GIT) cancers have shown that circZFR could be involved in the development and progression of various GIT cancers. However, small sample sizes limit the clinical significance of these studies. Here, a meta-analysis was conducted to ascertain the actual involvement of circZFR in the development and prognosis of GIT cancers. Methods: PubMed, Embase, Web of Science, and the Cochrane Library were searched up to December 31, 2023. Hazard ratios (HRs) or odds ratios (ORs) with 95% confidence intervals (CIs) were pooled to evaluate the association between circZFR expression and overall survival (OS). Publication bias was measured using the funnel plot and Egger’s test. Results: 10 studies having 659 participants were enrolled for meta-analysis. High circZFR expression was associated with poor OS (HR = 1.4, 95% CI: 1.20, 1.70). High circZFR expression also predicted larger tumor size (OR = 4.38, 95% CI 2.65, 7.25), advanced clinical stage (OR = 5.33, 95% CI 3.10, 9.16), and tendency for distant metastasis (OR = 2.89, 95% CI: 1.62, 5.11), but was not related to age, gender, and histological grade. Conclusions: In summary, high circZFR expression was associated with poor OS, larger tumor size, advanced stage cancer and tendency for distant metastasis. These findings suggested that circZFR could be a prognostic marker for GIT cancers. 展开更多
关键词 CircZFR GASTROINTESTINAL PROGNOSTIC SIGNIFICANCE META-ANALYSIS
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Research on Multi-Wave Pore Pressure Prediction Method Based on Three Field Velocity Fusion
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作者 Junlin zhang Huan Wan +2 位作者 yu zhang yumei He Linlin Dan 《Journal of Geoscience and Environment Protection》 2024年第6期269-278,共10页
The optimization of velocity field is the core issue in reservoir seismic pressure prediction. For a long time, the seismic processing velocity analysis method has been used in the establishment of pressure prediction... The optimization of velocity field is the core issue in reservoir seismic pressure prediction. For a long time, the seismic processing velocity analysis method has been used in the establishment of pressure prediction velocity field, which has a long research period and low resolution and restricts the accuracy of seismic pressure prediction;This paper proposed for the first time the use of machine learning algorithms, based on the feasibility analysis of wellbore logging pressure prediction, to integrate the CVI velocity inversion field, velocity sensitive post stack attribute field, and AVO P-wave and S-wave velocity reflectivity to obtain high-precision seismic P and S wave velocities. On this basis, high-resolution formation pore pressure and other parameters prediction based on multi waves is carried out. The pressure prediction accuracy is improved by more than 50% compared to the P-wave resolution of pore pressure prediction using only root mean square velocity. Practice has proven that the research method has certain reference significance for reservoir pore pressure prediction. 展开更多
关键词 Velocity Field RESOLUTION Machine Learning AVO Inversion Pore Pressure
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Research on Fracture Prediction Method Based on Multi-Source Information Fusion
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作者 yu zhang Junlin zhang +1 位作者 Shengli Xu Lina Yang 《Journal of Geoscience and Environment Protection》 2024年第6期291-304,共14页
Machine learning is a good method for predicting fracture by integrating multi-source information. Post-stack seismic attributes are commonly used to predict medium to large fractures, while pre-stack seismic attribut... Machine learning is a good method for predicting fracture by integrating multi-source information. Post-stack seismic attributes are commonly used to predict medium to large fractures, while pre-stack seismic attributes are proven to be more sensitive to small and micro sized fractures through forward modeling. Using machine learning algorithm to fuse information from different scales to predict fracture can greatly improve the accuracy of fracture prediction. On the basis of In-Situ stress prediction, the paper conducted post-stack seismic attribute analysis and pre-stack seismic attribute analysis, further studied on the sensitivity of seismic attributes to fracture and selected sensitive attributes, used the sensitivity log of well-bore fractures as the target log for learning, ultimately obtained a comprehensive body of fracture. Through blind well verification, the prediction results match well with the we1l data and the prediction results is highly consistent with the production data. The results of fracture prediction are reliable, and the research method has certain reference significance for fracture prediction. 展开更多
关键词 In-Situ Stress Fracture Prediction Seismic Attribute Machine Learning
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行为公共政策的工具设计、应用策略与政策效应:基于类型学的分析
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作者 满小欧 张雨 《公共行政评论》 北大核心 2024年第5期179-195,200,共18页
行为公共政策的兴起使公共政策研究逐渐转向对个体行为决策的微观解释及有效干预,然而当前研究多局限于“助推”,一定程度上忽视了行为公共政策工具丛的拓展及其策略与效应的差异。论文基于政策工具的干预对象与干预核心,创新性地构建... 行为公共政策的兴起使公共政策研究逐渐转向对个体行为决策的微观解释及有效干预,然而当前研究多局限于“助推”,一定程度上忽视了行为公共政策工具丛的拓展及其策略与效应的差异。论文基于政策工具的干预对象与干预核心,创新性地构建了需求行为型、需求能力型和供给行为型的行为公共政策工具类型学分析框架,并从三个主维度和六个子维度分别对四类行为公共政策工具,即助推、强推、助力和督推进行了系统深描与比较分析。研究表明,尽管行为公共政策工具均瞄准传统工具难以应对的“个体失灵”与“行为偏差”问题,但其干预策略不尽相同。政策制定者应在系统分析政策情境与实践场域的前提下,合理选择政策工具及其组合,以提高政策执行成效。 展开更多
关键词 行为公共政策 政策工具 类型学 比较分析
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COX-2/PGE2/EP4轴诱导巨噬细胞功能活化在NSCLC发展过程中的作用
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作者 赵娟 朱倩莹 +4 位作者 张宇 黎贵芸 张映林 李方方 边莉 《中国肺癌杂志》 CAS CSCD 北大核心 2024年第4期245-256,共12页
背景与目的肿瘤微环境(tumor microenvironment,TME)是肿瘤发生、发展的重要因素之一,其中肿瘤相关巨噬细胞(tumor-associated macrophages,TAMs)在非小细胞肺癌(non-small cell lung cancer,NSCLC)进展中起着重要作用。然而,TAMs在NSCL... 背景与目的肿瘤微环境(tumor microenvironment,TME)是肿瘤发生、发展的重要因素之一,其中肿瘤相关巨噬细胞(tumor-associated macrophages,TAMs)在非小细胞肺癌(non-small cell lung cancer,NSCLC)进展中起着重要作用。然而,TAMs在NSCLC发展过程中的作用机制仍不清楚,因此本研究旨在探讨TAMs在NSCLC发展过程中的作用,并寻找潜在的治疗靶点。方法使用GEPIA(Gene Expression Profiling Interactive Analysis)数据库分析前列腺素E2受体4(prostaglandin E2 receptor 4,EP4)mRNA在NSCLC和正常肺组织中的表达情况;利用免疫组化(immunohistochemistry,IHC)方法检测120例NSCLC组织及24例癌旁组织标本中环氧合酶-2(cyclooxygenase-2,COX-2)、EP4、分化簇86(cluster of differentiation 86,CD86)、CD163、CD31的蛋白表达水平;建立裸鼠肺腺癌细胞A549与巨噬细胞RAW264.7共移植瘤模型,使用EP4抑制剂E7046灌胃,收集样本行苏木素-伊红(hematoxylin-eosin,HE)、IHC和免疫荧光(immunofluorescence,IF)染色,免疫印迹(Western blot)检测各组裸鼠肿瘤组织上皮间充质转化(epithelial-mesenchymal transformation,EMT)相关蛋白表达情况;全长转录组测序技术筛选引起肿瘤肝转移的关键基因并进行KEGG(Kyoto Encyclopedia of Genes and Genomes)富集分析。结果EP4 mRNA在NSCLC组织中表达水平普遍低于正常肺组织(P<0.05);COX-2、EP4、CD163、CD31蛋白在NSCLC组织和癌旁组织中差异性表达且在NSCLC患者多项临床病理参数中存在差异;RAW264.7缩短了A549的成瘤潜伏期,促进肿瘤增殖及肿瘤肝转移,E7046可降低裸鼠肿瘤细胞增殖活性、肿瘤组织血管密度及M2型巨噬细胞浸润;IF染色显示巨噬细胞主要分布在肿瘤转移灶周围;Western blot结果显示与A549单独移植组相比,A549与RAW264.7共移植组小鼠肿瘤组织中E-钙黏蛋白(E-cadherin)相对表达量明显降低,差异具有统计学意义(P<0.05),N-钙黏蛋白(N-cadherin)相对表达量上调,但差异无统计学意义(P>0.05);全长转录组差异基因主要富集的通路为PI3K-AKT、MAPK信号通路。结论在NSCLC发生发展过程中,COX-2/PGE2/EP4轴可能通过诱导巨噬细胞功能活化来促进肿瘤的进展,EP4可能是具有潜力的肿瘤免疫治疗新靶点。本研究为深入探讨NSCLC的发生发展机制提供了新的视角和思路,同时为开发新的NSCLC治疗策略提供了理论依据。 展开更多
关键词 肺肿瘤 PGE2 EP4 巨噬细胞 肿瘤免疫
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Influence of Irregular Coastlines on a Tornadic Mesovortex in the Pearl River Delta during the Monsoon Season. Part Ⅰ:Pre-storm Environment and Storm Evolution 被引量:1
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作者 Lanqiang BAI Dan YAO +4 位作者 Zhiyong MENG yu zhang Xianxiang HUANG Zhaoming LI Xiaoding yu 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1115-1131,共17页
The Pearl River Delta(PRD),a tornado hotspot,forms a distinct trumpet-shaped coastline that concaves toward the South China Sea.During the summer monsoon season,low-level southwesterlies over the PRD’s sea surface te... The Pearl River Delta(PRD),a tornado hotspot,forms a distinct trumpet-shaped coastline that concaves toward the South China Sea.During the summer monsoon season,low-level southwesterlies over the PRD’s sea surface tend to be turned toward the west coast,constituting a convergent wind field along with the landward-side southwesterlies,which influences regional convective weather.This two-part study explores the roles of this unique land–sea contrast of the trumpet-shaped coastline in the formation of a tornadic mesovortex within monsoonal flows in this region.Part I primarily presents observational analyses of pre-storm environments and storm evolutions.The rotating storm developed in a lowshear environment(not ideal for a supercell)under the interactions of three air masses under the influence of the land–sea contrast,monsoon,and storm cold outflows.This intersection zone(or“triple point”)is typically characterized by local enhancements of ambient vertical vorticity and convergence.Based on a rapid-scan X-band phased-array radar,finger-like echoes were recognized shortly after the gust front intruded on the triple point.Developed over the triple point,they rapidly wrapped up with a well-defined low-level mesovortex.It is thus presumed that the triple point may have played roles in the mesovortex genesis,which will be demonstrated in Part II with multiple sensitivity numerical simulations.The findings also suggest that when storms pass over the boundary intersection zone in the PRD,the expected possibility of a rotating storm occurring is relatively high,even in a low-shear environment.Improved knowledge of such environments provides additional guidance to assess the regional tornado risk. 展开更多
关键词 TORNADO mesovortex surface boundary land–sea contrast MONSOON
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Porous metal oxides in the role of electrochemical CO_(2) reduction reaction 被引量:1
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作者 Ziqi zhang Jinyun Xu +9 位作者 yu zhang Liping Zhao Ming Li Guoqiang Zhong Di Zhao Minjing Li Xudong Hu Wenju Zhu Chunming Zheng Xiaohong Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期373-398,I0009,共27页
The global energy-related CO_(2) emissions have rapidly increased as the world economy heavily relied on fossil fuels.This paper explores the pressing challenge of CO_(2) emissions and highlights the role of porous me... The global energy-related CO_(2) emissions have rapidly increased as the world economy heavily relied on fossil fuels.This paper explores the pressing challenge of CO_(2) emissions and highlights the role of porous metal oxide materials in the electrocatalytic reduction of CO_(2)(CO_(2)RR).The focus is on the development of robust and selective catalysts,particularly metal and metal-oxide-based materials.Porous metal oxides offer high surface area,enhancing the accessibility to active sites and improving reaction kinetics.The tunability of these materials allows for tailored catalytic behavior,targeting optimized reaction mechanisms for CO_(2)RR.The work also discusses the various synthesis strategies and identifies key structural and compositional features,addressing challenges like high overpotential,poor selectivity,and low stability.Based on these insights,we suggest avenues for future research on porous metal oxide materials for electrochemical CO_(2) reduction. 展开更多
关键词 CO_(2)reduction Carbon dioxide TRANSFORMATION Porous metal oxides ELECTROCATALYSIS
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Automatic detection of small bowel lesions with different bleeding risks based on deep learning models 被引量:1
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作者 Rui-Ya zhang Peng-Peng Qiang +5 位作者 Ling-Jun Cai Tao Li Yan Qin yu zhang Yi-Qing Zhao Jun-Ping Wang 《World Journal of Gastroenterology》 SCIE CAS 2024年第2期170-183,共14页
BACKGROUND Deep learning provides an efficient automatic image recognition method for small bowel(SB)capsule endoscopy(CE)that can assist physicians in diagnosis.However,the existing deep learning models present some ... BACKGROUND Deep learning provides an efficient automatic image recognition method for small bowel(SB)capsule endoscopy(CE)that can assist physicians in diagnosis.However,the existing deep learning models present some unresolved challenges.AIM To propose a novel and effective classification and detection model to automatically identify various SB lesions and their bleeding risks,and label the lesions accurately so as to enhance the diagnostic efficiency of physicians and the ability to identify high-risk bleeding groups.METHODS The proposed model represents a two-stage method that combined image classification with object detection.First,we utilized the improved ResNet-50 classification model to classify endoscopic images into SB lesion images,normal SB mucosa images,and invalid images.Then,the improved YOLO-V5 detection model was utilized to detect the type of lesion and its risk of bleeding,and the location of the lesion was marked.We constructed training and testing sets and compared model-assisted reading with physician reading.RESULTS The accuracy of the model constructed in this study reached 98.96%,which was higher than the accuracy of other systems using only a single module.The sensitivity,specificity,and accuracy of the model-assisted reading detection of all images were 99.17%,99.92%,and 99.86%,which were significantly higher than those of the endoscopists’diagnoses.The image processing time of the model was 48 ms/image,and the image processing time of the physicians was 0.40±0.24 s/image(P<0.001).CONCLUSION The deep learning model of image classification combined with object detection exhibits a satisfactory diagnostic effect on a variety of SB lesions and their bleeding risks in CE images,which enhances the diagnostic efficiency of physicians and improves the ability of physicians to identify high-risk bleeding groups. 展开更多
关键词 Artificial intelligence Deep learning Capsule endoscopy Image classification Object detection Bleeding risk
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Spatial transcriptomics reveals that metabolic characteristics define the tumor immunosuppression microenvironment via iCAF transformation in oral squamous cell carcinoma 被引量:1
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作者 Zheqi Liu Zhen zhang +7 位作者 yu zhang Wenkai Zhou Xu zhang Canbang Peng Tong Ji Xin Zou Zhiyuan zhang Zhenhu Ren 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第1期110-121,共12页
Tumor progression is closely related to tumor tissue metabolism and reshaping of the microenvironment. Oral squamous cell carcinoma (OSCC), a representative hypoxic tumor, has a heterogeneous internal metabolic enviro... Tumor progression is closely related to tumor tissue metabolism and reshaping of the microenvironment. Oral squamous cell carcinoma (OSCC), a representative hypoxic tumor, has a heterogeneous internal metabolic environment. To clarify the relationship between different metabolic regions and the tumor immune microenvironment (TME) in OSCC, Single cell (SC) and spatial transcriptomics (ST) sequencing of OSCC tissues were performed. The proportion of TME in the ST data was obtained through SPOTlight deconvolution using SC and GSE103322 data. The metabolic activity of each spot was calculated using scMetabolism,and k-means clustering was used to classify all spots into hyper-, normal-, or hypometabolic regions. CD4T cell infiltration and TGF-βexpression is higher in the hypermetabolic regions than in the others. Through CellPhoneDB and NicheNet cell-cell communication analysis, it was found that in the hypermetabolic region, fibroblasts can utilize the lactate produced by glycolysis of epithelial cells to transform into inflammatory cancer-associated fibroblasts (iCAFs), and the increased expression of HIF1A in iCAFs promotes the transcriptional expression of CXCL12. The secretion of CXCL12 recruits regulatory T cells (Tregs), leading to Treg infiltration and increased TGF-β secretion in the microenvironment and promotes the formation of a tumor immunosuppressive microenvironment. This study delineates the coordinate work axis of epithelial cells-iCAFs-Tregs in OSCC using SC, ST and TCGA bulk data, and highlights potential targets for therapy. 展开更多
关键词 CXCL12 MICROENVIRONMENT SQUAMOUS
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Cytokine release syndrome triggered by programmed death 1 blockade(sintilimab)therapy in a psoriasis patient:A case report 被引量:1
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作者 Ming-Hui Zhou Min-Feng Ye +2 位作者 Zhen-Xing zhang Feng Tao yu zhang 《World Journal of Clinical Cases》 SCIE 2024年第18期3555-3560,共6页
BACKGROUND In recent years,immune checkpoint inhibitors(ICIs)have demonstrated remarkable efficacy across diverse malignancies.Notably,in patients with advanced gastric cancer,the use of programmed death 1(PD-1)blocka... BACKGROUND In recent years,immune checkpoint inhibitors(ICIs)have demonstrated remarkable efficacy across diverse malignancies.Notably,in patients with advanced gastric cancer,the use of programmed death 1(PD-1)blockade has significantly prolonged overall survival,marking a pivotal advancement comparable to the impact of Herceptin over the past two decades.While the therapeutic benefits of ICIs are evident,the increasing use of immunotherapy has led to an increase in immune-related adverse events.CASE SUMMARY This article presents the case of a patient with advanced gastric cancer and chronic plaque psoriasis.Following sintilimab therapy,the patient developed severe rashes accompanied by cytokine release syndrome(CRS).Fortunately,effective management was achieved through the administration of glucocorticoid,tocilizumab,and acitretin,which resulted in favorable outcomes.CONCLUSION Glucocorticoid and tocilizumab therapy was effective in managing CRS after PD-1 blockade therapy for gastric cancer in a patient with chronic plaque psoriasis. 展开更多
关键词 Cytokine release syndrome Programmed death 1 blockade Sintilimab PSORIASIS Gastric cancer Case report
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消失的对话性:作为伪命题的AI时评
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作者 张宇 曹林 《全球传媒学刊》 2024年第3期42-56,共15页
人工智能对新闻业的影响已从信息类的新闻报道领域渗透至观点性的新闻评论,AI时评给被视为“不可被机器替代的最后领地”的评论写作带来某种挑战。本文认为,AI时评不符合新闻评论的对话性要求,有智能而无智识,有套话而无对话,有答案而... 人工智能对新闻业的影响已从信息类的新闻报道领域渗透至观点性的新闻评论,AI时评给被视为“不可被机器替代的最后领地”的评论写作带来某种挑战。本文认为,AI时评不符合新闻评论的对话性要求,有智能而无智识,有套话而无对话,有答案而无问答。本研究通过分析AI小壹创作的26篇时评文章,从选题、行文和效果三方面探究AI写作如何消灭了新闻评论的对话性。对话性的缺失,让AI时评只能成为一场自言自语的“对空言说”。人化的AI时评目前还无法取代人的写作,但对机器化的“人的写作”形成了一种反向测试。 展开更多
关键词 AI时评 新闻评论 对话性
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How do lateral septum projections to the ventral CA1 influence sociability?
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作者 Dan Wang Di Zhao +12 位作者 Wentao Wang Fengai Hu Minghu Cui Jing Liu Fantao Meng Cuilan Liu Changyun Qiu Dunjiang Liu Zhicheng Xu Yameng Wang yu zhang Wei Li Chen Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1789-1801,共13页
Social dysfunction is a risk factor for several neuropsychiatric illnesses.Previous studies have shown that the lateral septum(LS)-related pathway plays a critical role in mediating social behaviors.Howeve r,the role ... Social dysfunction is a risk factor for several neuropsychiatric illnesses.Previous studies have shown that the lateral septum(LS)-related pathway plays a critical role in mediating social behaviors.Howeve r,the role of the connections between the LS and its downstream brain regions in social behavio rs remains unclea r.In this study,we conducted a three-chamber test using electrophysiological and chemogenetic approaches in mice to determine how LS projections to ventral CA1(vCA1)influence sociability.Our res ults showed that gamma-aminobutyric acid(GABA)-e rgic neuro ns were activated following social experience,and that social behavio rs were enhanced by chemogenetic modulation of these neurons.Moreover,LS GABAergic neurons extended their functional neural connections via vCA1 glutamatergic pyramidal neurons,and regulating LSGABA→vCA1Gluneural projections affected social behaviors,which were impeded by suppressing LSprojecting vCA1 neuronal activity or inhibiting GABAAreceptors in vCA1.These findings support the hypothesis that LS inputs to the vCA1 can control social prefe rences and social novelty behaviors.These findings provide new insights rega rding the neural circuits that regulate sociability. 展开更多
关键词 chemogenetics GABA receptor GABAergic neurons glutamatergic neurons lateral septum neural excitability neural projection social novelty social preference ventral CA1
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Formation mechanism of nanopores in dense films of anodic alumina
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作者 Peng-ze LI yu zhang +5 位作者 Jia-zheng zhang Lin LIU Shi-yi WANG Rui LIU Ye SONG Xu-fei ZHU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2918-2927,共10页
Constant-current anodization of pure aluminum was carried out in non-corrosive capacitor working electrolytes to study the formation mechanism of nanopores in the anodic oxide films.Through comparative experiments,nan... Constant-current anodization of pure aluminum was carried out in non-corrosive capacitor working electrolytes to study the formation mechanism of nanopores in the anodic oxide films.Through comparative experiments,nanopores are found in the anodic films formed in the electrolytes after high-temperature storage(HTS)at 130°C for 240 h.A comparison of the voltage-time curves suggests that the formation of nanopores results from the decrease in formation efficiency of anodic oxide films rather than the corrosion of the electrolytes.FT-IR and UV spectra analysis shows that carboxylate and ethylene glycol in electrolytes can easily react by esterification at high temperatures.Combining the electronic current theory and oxygen bubble mold effect,the change in electrolyte composition could increase the electronic current in the anodizing process.The electronic current decreases the formation efficiency of anodic oxide films,and oxygen bubbles accompanying electronic current lead to the formation of nanopores in the dense films.The continuous electronic current and oxygen bubbles are the prerequisites for the formation of porous anodic oxides rather than the traditional field-assisted dissolution model. 展开更多
关键词 anodic alumina formation mechanism NANOPORES formation efficiency electronic current oxygen bubble
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Influence of Irregular Coastlines on a Tornadic Mesovortex in the Pearl River Delta during Monsoon Season.Part II:Numerical Experiments
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作者 Lanqiang BAI Dan YAO +3 位作者 Zhiyong MENG yu zhang Xianxiang HUANG Zhaoming LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第9期1704-1720,共17页
As demonstrated in the first part of this study(Part I),wind-shift boundaries routinely form along the west coast of the Pearl River Delta due to the land-sea contrast of a“trumpet”shape coastline in the summer mons... As demonstrated in the first part of this study(Part I),wind-shift boundaries routinely form along the west coast of the Pearl River Delta due to the land-sea contrast of a“trumpet”shape coastline in the summer monsoon season.Through multiple numerical simulations,this article(Part II)aims to examine the roles of the trumpet-shaped coastline in the mesovortex genesis during the 1 June 2020 tornadic event.The modeling reproduced two mesovortices that are in close proximity in time and space to the realistic mesovortices.In addition to the modeled mesovortex over the triple point where strong ambient vertical vorticity was located,another mesovortex originated from an enhanced discrete vortex along an airmass boundary via shear instability.On the fine-scale storm morphology,finger-like echoes preceding hook echoes were also reproduced around the triple point.Results from sensitivity experiments suggest that the unique topography plays an essential role in modifying the vorticity budget during the mesovortex formation.While there is a high likelihood of an upcoming storm evolving into a rotating storm over the triple point,the simulation's accuracy is sensitive to the local environmental details and storm dynamics.The strengths of cold pool surges from upstream storms may influence the stretching of low-level vertically oriented vortex and thus the wrap-up of finger-like echoes.These findings suggest that the trumpet-shaped coastline is an important component of mesovortex production during the active monsoon season.It is hoped that this study will increase the situational awareness for forecasters regarding regional non-mesocyclone tornadic environments. 展开更多
关键词 mesovortex TORNADO land-sea contrast COASTLINE MONSOON
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Lightweight Dual‑Functional Segregated Nanocomposite Foams for Integrated Infrared Stealth and Absorption‑Dominant Electromagnetic Interference Shielding
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作者 Zhonglei Ma Ruochu Jiang +8 位作者 Jiayao Jing Songlei Kang Li Ma Kefan zhang Junxian Li yu zhang Jianbin Qin Shuhuan yun Guangcheng zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第11期38-55,共18页
Lightweight infrared stealth and absorption-dominant electromagnetic interference(EMI)shielding materials are highly desirable in areas of aerospace,weapons,military and wearable electronics.Herein,lightweight and hig... Lightweight infrared stealth and absorption-dominant electromagnetic interference(EMI)shielding materials are highly desirable in areas of aerospace,weapons,military and wearable electronics.Herein,lightweight and high-efficiency dual-functional segregated nanocomposite foams with microcellular structures are developed for integrated infrared stealth and absorption-dominant EMI shielding via the efficient and scalable supercritical CO_(2)(SC-CO_(2))foaming combined with hydrogen bonding assembly and compression molding strategy.The obtained lightweight segregated nanocomposite foams exhibit superior infrared stealth performances benefitting from the synergistic effect of highly effective thermal insulation and low infrared emissivity,and outstanding absorption-dominant EMI shielding performances attributed to the synchronous construction of microcellular structures and segregated structures.Particularly,the segregated nanocomposite foams present a large radiation temperature reduction of 70.2℃ at the object temperature of 100℃,and a significantly improved EM wave absorptivity/reflectivity(A/R)ratio of 2.15 at an ultralow Ti_(3)C_(2)T_(x) content of 1.7 vol%.Moreover,the segregated nanocomposite foams exhibit outstanding working reliability and stability upon dynamic compression cycles.The results demonstrate that the lightweight and high-efficiency dual-functional segregated nanocomposite foams have excellent potentials for infrared stealth and absorption-dominant EMI shielding applications in aerospace,weapons,military and wearable electronics. 展开更多
关键词 Segregated nanocomposite foams Microcellular structures Infrared stealth EMI shielding Low infrared emissivity
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Atomically Dispersed Ruthenium Catalysts with Open Hollow Structure for Lithium-Oxygen Batteries
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作者 Xin Chen yu zhang +5 位作者 Chang Chen Huinan Li yuran Lin Ke yu Caiyun Nan Chen Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期154-164,共11页
Lithium–oxygen battery with ultrahigh theoretical energy density is considered a highly competitive next-generation energy storage device,but its practical application is severely hindered by issues such as difficult... Lithium–oxygen battery with ultrahigh theoretical energy density is considered a highly competitive next-generation energy storage device,but its practical application is severely hindered by issues such as difficult decomposition of discharge products at present.Here,we have developed N-doped carbon anchored atomically dispersed Ru sites cathode catalyst with open hollow structure(h-RuNC)for Lithium–oxygen battery.On one hand,the abundance of atomically dispersed Ru sites can effectively catalyze the formation and decomposition of discharge products,thereby greatly enhancing the redox kinetics.On the other hand,the open hollow structure not only enhances the mass activity of atomically dispersed Ru sites but also improves the diffusion efficiency of catalytic molecules.Therefore,the excellent activity from atomically dispersed Ru sites and the enhanced diffusion from open hollow structure respectively improve the redox kinetics and cycling stability,ultimately achieving a high-performance lithium–oxygen battery. 展开更多
关键词 Atomically dispersed Open hollow structure Discharge product LITHIUM Oxygen battery
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Designing Symmetric Gradient Honeycomb Structures with Carbon‑Coated Iron‑Based Composites for High‑Efficiency Microwave Absorption
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作者 yu zhang Shu‑Hao Yang +9 位作者 yue Xin Bo Cai Peng‑Fei Hu Hai‑Yang Dai Chen‑Ming Liang yun‑Tong Meng Ji‑Hao Su Xiao‑Juan zhang Min Lu Guang‑Sheng Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第11期224-241,共18页
The impedance matching of absorbers is a vital factor affecting their microwave absorption(MA)properties.In this work,we controllably synthesized Material of Institute Lavoisier 88C(MIL-88C)with varying aspect ratios(... The impedance matching of absorbers is a vital factor affecting their microwave absorption(MA)properties.In this work,we controllably synthesized Material of Institute Lavoisier 88C(MIL-88C)with varying aspect ratios(AR)as a precursor by regulating oil bath conditions,followed by one-step thermal decomposition to obtain carbon-coated iron-based composites.Modifying the precursor MIL-88C(Fe)preparation conditions,such as the molar ratio between metal ions and organic ligands(M/O),oil bath temperature,and oil bath time,influenced the phases,graphitization degree,and AR of the derivatives,enabling low filler loading,achieving well-matched impedance,and ensuring outstanding MA properties.The MOF-derivatives 2(MD_(2))/polyvinylidene Difluoride(PVDF),MD_(3)/PVDF,and MD4/PVDF absorbers all exhibited excellent MA properties with optimal filler loadings below 20 wt%and as low as 5 wt%.The MD_(2)/PVDF(5 wt%)achieved a maximum effective absorption bandwidth(EAB)of 5.52 GHz(1.90 mm).The MD_(3)/PVDF(10 wt%)possessed a minimum reflection loss(RL_(min))value of−67.4 at 12.56 GHz(2.13 mm).A symmetric gradient honeycomb structure(SGHS)was constructed utilizing the high-frequency structure simulator(HFSS)to further extend the EAB,achieving an EAB of 14.6 GHz and a RL_(min) of−59.0 dB.This research offers a viable inspiration to creating structures or materials with high-efficiency MA properties. 展开更多
关键词 MIL-88C(Fe) Fe/Fe_(3)O_(4)/Fe_(3)C@C Controllable preparation Symmetric gradient honeycomb structure Microwave absorbing
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Gut microbiome and serum metabolome analyses identify Bacteroides fragilis as regulators of serotonin content and PRL secretion in broody geese
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作者 yu zhang Ning Zhou +7 位作者 Jia Wu Lina Song Qiang Bao Kaiqi Weng Yang zhang Wanwipa Vongsangnak Guohong Chen Qi Xu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期2033-2051,共19页
Broody behavior is regulated by hypothalamic prolactin secretion,which seriously affects egg production in poulty production.Numerous studies have provided evidence that animal behavior is governed by dynamic bidirect... Broody behavior is regulated by hypothalamic prolactin secretion,which seriously affects egg production in poulty production.Numerous studies have provided evidence that animal behavior is governed by dynamic bidirectional communication between specific gut bacteria and their host via the brain-gut-microbiome axis.However,little research focused on how the gut microbiota influence broody behavior in poultry.In this study,Zhedong white geese in laying and brooding phases were selected.Ten differentially abundant bacteria in cecum were detected between brooding and laying geese through metagenomic analyses and 16S rRNA sequencing(P<0.05),and Bacteroides fragilis was specifically identified as a key driver species in the brooding geese.Moverover,the serum metabolites were quantified,and the 313 differentially abundant metabolites were found between the two groups of different physiological geese.They were primarily enriched in the tryptophan metabolism pathways.Pearson correlation analyses revealed there was a significant positive correlation between B.fragilis abundance and the context of 11 tryptophan metabolism-related metabolites(such as serotonin,etc.)in broody geese,which hinted that those tryptophan metabolites might be produced or driven by B.fragilis.Finally,the serum hormone levels were also measured.We found there was a positive correlation between B.fragilis abundance and content of serotonin.Besides,prolactin secreted by the pituitary gland was greater in brooding geese than that in laying geese,which was also highly correlated with B.fragilis abundance.This result implied that B.fragilis could promote the secretion of prolactin by the pituitary gland.Together,the current study findings provided the information on gut microbiota influencing broody behavior,B.fragilis produced or driven more serum serotonin,and stimulated the pituitary gland to secret more prolactin,which potentially offered a new enlightenment for the intervention of broody behavior in poultry. 展开更多
关键词 GEESE broody behavior gut microbiota SEROTONIN PROLACTIN
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Interfacial Electronic Modulation of Dual-Monodispersed Pt–Ni_(3)S_(2) as Efficacious Bi-Functional Electrocatalysts for Concurrent H_(2) Evolution and Methanol Selective Oxidation
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作者 Qianqian Zhao Bin Zhao +7 位作者 Xin Long Renfei Feng Mohsen Shakouri Alisa Paterson Qunfeng Xiao yu zhang Xian‑Zhu Fu Jing‑Li Luo 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期415-431,共17页
Constructing the efficacious and applicable bifunctional electrocatalysts and establishing out the mechanisms of organic electro-oxidation by replacing anodic oxygen evolution reaction(OER) are critical to the develop... Constructing the efficacious and applicable bifunctional electrocatalysts and establishing out the mechanisms of organic electro-oxidation by replacing anodic oxygen evolution reaction(OER) are critical to the development of electrochemicallydriven technologies for efficient hydrogen production and avoid CO_(2) emission. Herein, the hetero-nanocrystals between monodispersed Pt(~ 2 nm) and Ni_(3)S_(2)(~ 9.6 nm) are constructed as active electrocatalysts through interfacial electronic modulation, which exhibit superior bi-functional activities for methanol selective oxidation and H_(2) generation. The experimental and theoretical studies reveal that the asymmetrical charge distribution at Pt–Ni_(3)S_(2) could be modulated by the electronic interaction at the interface of dual-monodispersed heterojunctions, which thus promote the adsorption/desorption of the chemical intermediates at the interface. As a result, the selective conversion from CH_(3)OH to formate is accomplished at very low potentials(1.45 V) to attain 100 m A cm^(-2) with high electronic utilization rate(~ 98%) and without CO_(2) emission. Meanwhile, the Pt–Ni_(3)S_(2) can simultaneously exhibit a broad potential window with outstanding stability and large current densities for hydrogen evolution reaction(HER) at the cathode. Further, the excellent bi-functional performance is also indicated in the coupled methanol oxidation reaction(MOR)//HER reactor by only requiring a cell voltage of 1.60 V to achieve a current density of 50 m A cm^(-2) with good reusability. 展开更多
关键词 Dual-monodispersed heterostructure Electronic interactive modulation Reaction mechanism Methanol oxidation reaction Hydrogen generation
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Non-destructive buffer enabling near-infrared-transparent inverted inorganic perovskite solar cells toward 1400 h light-soaking stable perovskite/Cu(In,Ga)Se_(2) tandem solar cells
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作者 yu zhang Zhaoheng Tang +14 位作者 Zhongyang zhang Jiahong Tang Minghua Li Siyuan Zhu Wenyan Tan Xi Jin Tongsheng Chen Jinsong Hu Chao Zhou Chunlei Yang Qijie Liang Xugang Guo Weimin Li Weiqiang Chen Yan Jiang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期622-629,I0013,共9页
Near-infrared(NIR)transparent inverted all-inorganic perovskite solar cells(PSCs)are excellent top cell candidates in tandem applications.An essential challenge is the replacement of metal contacts with transparent co... Near-infrared(NIR)transparent inverted all-inorganic perovskite solar cells(PSCs)are excellent top cell candidates in tandem applications.An essential challenge is the replacement of metal contacts with transparent conductive oxide(TCO)electrodes,which requires the introduction of a buffer layer to prevent sputtering damage.In this study,we show that the conventional buffers(i.e.,small organic molecules and atomic layer deposited metal oxides)used for organic-inorganic hybrid perovskites are not applicable to all-inorganic perovskites,due to non-uniform coverage of the vulnerable layers underneath,deterioration upon ion bombardment and moisture induced perovskite phase transition,A thin film of metal oxide nanoparticles by the spin-coating method serves as a non-destructive buffer layer for inorganic PSCs.All-inorganic inverted near-infrared-transparent PSCs deliver a PCE of 17.46%and an average transmittance of 73.7%between 780 and 1200 nm.In combination with an 18.56%Cu(In,Ga)Se_(2) bottom cell,we further demonstrate the first all-inorganic perovskite/CIGS 4-T tandem solar cell with a PCE of 24.75%,which exhibits excellent illumination stability by maintaining 86.7%of its initial efficiency after 1400 h.The non-destructive buffer lays the foundation for efficient and stable NIR-transparent inverted inorganic perovskite solar cells and perovskite-based tandems. 展开更多
关键词 CsPbI_(3)perovskite Inverted perovskite solar cells Tandem solar cells Buffer layer Stability
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