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血栓通对阿尔茨海默症模型小鼠认知功能及神经异常兴奋性的作用及其机制研究
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作者 刘慧 严国纪 +3 位作者 吴嘉 王丹 习杨彦彬 李珊珊 《昆明医科大学学报》 CAS 2024年第2期23-31,共9页
目的探究血栓通[主要有效成分为三七皂苷(panax notoginseng,PNS)]对阿尔茨海默症(Alzheimer’s disease,AD)模型小鼠认知功能及神经兴奋性的影响,并探讨其潜在分子机制。方法用APP/PS1小鼠作为AD研究动物模型,在小鼠淀粉样蛋白尚未检... 目的探究血栓通[主要有效成分为三七皂苷(panax notoginseng,PNS)]对阿尔茨海默症(Alzheimer’s disease,AD)模型小鼠认知功能及神经兴奋性的影响,并探讨其潜在分子机制。方法用APP/PS1小鼠作为AD研究动物模型,在小鼠淀粉样蛋白尚未检测到阶段(2月龄)开始每日以60 mg/kg对血栓通组(APP/PS1+PNS)行灌胃给药,每日1次,连续给药6个月(给药至8月龄);对照组小鼠予同等体积的0.9%氯化钠(APP/PS1+vehicle)灌胃处理,同月龄野生型小鼠予0.9%氯化钠灌胃处理作为正常对照组(WT+vehicle),每组各15只。6个月后,新物体识别实验、Morris水迷宫实验检测小鼠的认知功能;EEG脑电检测、Western blot、细胞表面生物素化试验以检测各组小鼠皮质与海马中BACE1的活性、Nav1.1α的分布、表达以及Navβ2的表达与酶解情况(Navβ2的酶解片段Navβ2 full length及Navβ2-CTF表达检测)。结果新物体识别实验显示,与对照组APP/PS1小鼠相比,血栓通用药后APP/PS1小鼠的辨别指数(discrimination index,DI)上升(P<0.05);Morris水迷宫检测结果发现,血栓通灌胃6个月后小鼠在探索实验中逃避潜伏期缩短(P<0.05),撤除平台后在目标象限停留时间增加(P<0.05)、穿梭平台次数增加(P<0.05);EEG脑电检测结果发现,血栓通给药后减少了APP/PS1小鼠棘波放电出现的频率(P<0.05)。血栓通给药后显著降低了BACE1蛋白水平的表达(P<0.05),而全长片段Navβ2的蛋白水平显著上升(P<0.05),并纠正了Nav1.1α在神经元内外的异常分布(P<0.05)。结论血栓通可以改善AD模型小鼠的学习记忆能力、纠正大脑异常兴奋性,其作用机制可能与抑制BACE1的活性从而减少Navβ2由APP/PS1诱导的过度酶解,纠正皮质、海马神经元Nav1.1α的异常表达与分布,调节神经元的兴奋性有关。 展开更多
关键词 血栓通 阿尔茨海默症 认知功能 BACE1 Navβ2酶解 Nav1.1α分布
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京津冀生态补偿是否具有“增绿”效应——来自国家重点生态功能区转移支付重点补助的证据
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作者 范庆泉 刘惠 +1 位作者 刘祎男 王子仲 《经济学报》 2024年第1期416-444,共29页
生态文明建设是促进经济社会发展全面绿色转型的战略布局,也是实现中国式现代化的本质要求。国家重点生态功能区转移支付重点补助作为修复改善生态环境的重要制度安排,是“十四五”期间推进生态文明建设迈上新台阶的重点工作,其政策效... 生态文明建设是促进经济社会发展全面绿色转型的战略布局,也是实现中国式现代化的本质要求。国家重点生态功能区转移支付重点补助作为修复改善生态环境的重要制度安排,是“十四五”期间推进生态文明建设迈上新台阶的重点工作,其政策效果评价及作用机制探究具有十分重要的现实意义。本文基于2002—2021年京津冀地区县级数据构造多期双重差分模型,对国家重点生态功能区转移支付重点补助政策的生态环境改善效应进行实证检验。研究表明,国家重点生态功能区转移支付重点补助改善了京津冀地区的生态环境质量,设立国家重点生态功能区的县域体现出更为显著的政策效果。此外,河北省相关制度实施时间更长、资金规模更大,该省的生态环境改善效果也更加明显。进一步,本文研究发现转移支付重点补助政策的作用机制是通过提高农村居民收入水平、增强生态环境保护的内在激励,优化其经济生产行为得以实现的。基于此,本文提出应加大激励约束措施实施力度、加速培育生态产业、在现有制度基础上探索横向转移支付的政策建议,以充分发挥国家重点生态功能区转移支付重点补助的政策导向功能,助力美丽中国目标早日实现。 展开更多
关键词 生态补偿 转移支付 国家重点生态功能区 双重差分模型
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天然植物多糖的提取、分离及其在皮肤领域的研究进展
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作者 刘慧 杨思佳 +3 位作者 任晗堃 曲召辉 郑立波 李姝静 《日用化学工业(中英文)》 CAS 北大核心 2024年第6期708-717,共10页
植物多糖是一种从植物各部位中提取的天然高分子聚合物,由十个或十个以上的单糖单元通过糖苷键聚合而成。近年来,由于其丰富的生物活性、安全性、亲肤性等特点越来越受到人们的关注。多糖的结构和功能之间具有密切关系,不同的提取和纯... 植物多糖是一种从植物各部位中提取的天然高分子聚合物,由十个或十个以上的单糖单元通过糖苷键聚合而成。近年来,由于其丰富的生物活性、安全性、亲肤性等特点越来越受到人们的关注。多糖的结构和功能之间具有密切关系,不同的提取和纯化方法会对多糖的结构产生影响,进而改变其生物活性。本文阐述了植物多糖的提取、分离、纯化工艺,并同时对植物多糖具有的保湿补水、抗氧化、抗炎、抑菌、美白等功效进行了总结,以期为植物多糖在功能化妆品的开发和应用提供理论支撑。 展开更多
关键词 植物多糖 保湿 抗氧化 抗炎 抑菌 美白 皮肤
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Elaidic acid leads to mitochondrial dysfunction via mitochondria-associated membranes triggers disruption of mitochondrial calcium fluxes 被引量:1
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作者 hui liu Xuenan Li +4 位作者 Ziyue Wang Lu Li Yucai Li Haiyang Yan Yuan Yuan 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期287-298,共12页
Elaidic acid(EA)stimulation can lead to endoplasmic reticulum stress(ERS),accompanied by a large release of Ca^(2+),and ultimately the activation of NLRP3 inflammasome in Kupffer cells(KCs).Mitochondrial instability o... Elaidic acid(EA)stimulation can lead to endoplasmic reticulum stress(ERS),accompanied by a large release of Ca^(2+),and ultimately the activation of NLRP3 inflammasome in Kupffer cells(KCs).Mitochondrial instability or dysfunction may be the key stimulating factors to activate NLRP3 inflammasome,and sustained Ca^(2+)transfer can result in mitochondrial dysfunction.We focused on KCs to explore the damage to mitochondria by EA.After EA stimulation,cells produced an oxidative stress(OS)response with a significant increase in ROS release.Immunoprecipitation experiments and the addition of inhibitors revealed that the increase in the level of intracellular Ca^(2+)led to Ca^(2+)accumulation in the mitochondrial matrix via mitochondria-associated membranes(MAMs).This was accompanied by a significant release of m ROS,loss of MMP and ATP,and a significant increase in mitochondrial permeability transition pore opening,ultimately leading to mitochondrial instability.These findings confirmed the mechanism that EA induced mitochondrial Ca^(2+)imbalance in KCs via MAM,ultimately leading to mitochondrial dysfunction.Meanwhile,EA induced OS and the decrease of MMP and ATP in rat liver,and significant lesions were found in liver mitochondria.Swelling of the inner mitochondrial cristae and mitochondrial vacuolization occurred,with a marked increase in lipid droplets. 展开更多
关键词 Elaidic acid(EA) Mitochondria-associated membranes(MAMs) Calcium Endoplasmic reticulum Mitochondria dysfunction
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油料作物育种的分子工具和技术创新 被引量:3
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作者 许玲 hui liu +3 位作者 Guijun YAN Wallace COWLING 周伟军 路战远 《浙江大学学报(农业与生命科学版)》 CAS CSCD 北大核心 2023年第4期445-453,共9页
油料作物的主要育种目标是提高产量、品质和抗逆性。目前,就产量而言,全球主要油料作物依次为大豆、油菜、向日葵和花生。本文综述了这些主要油料作物育种的分子工具和技术创新,包括基因组选择、基因组编辑、分子设计育种等新技术,指出... 油料作物的主要育种目标是提高产量、品质和抗逆性。目前,就产量而言,全球主要油料作物依次为大豆、油菜、向日葵和花生。本文综述了这些主要油料作物育种的分子工具和技术创新,包括基因组选择、基因组编辑、分子设计育种等新技术,指出了当前在遗传研究和育种实践中存在的主要问题,并对技术进展和未来应用前景进行了展望,旨在为油料作物高产、优质、高效育种提供借鉴。 展开更多
关键词 油料作物 育种 分子工具 技术创新
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Review on synergistic damage effect of irradiation and corrosion on reactor structural alloys
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作者 hui liu Guan-Hong Lei He-Fei Huang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期109-141,共33页
The synergistic damage effect of irradiation and corrosion of reactor structural materials has been a prominent research focus.This paper provides a comprehensive review of the synergistic effects on the third-and fou... The synergistic damage effect of irradiation and corrosion of reactor structural materials has been a prominent research focus.This paper provides a comprehensive review of the synergistic effects on the third-and fourth-generation fission nuclear energy structural materials used in pressurized water reactors and molten salt reactors.The competitive mechanisms of multiple influencing factors,such as the irradiation dose,corrosion type,and environmental temperature,are summarized in this paper.Conceptual approaches are proposed to alleviate the synergistic damage caused by irradiation and corrosion,thereby promoting in-depth research in the future and solving this key challenge for the structural materials used in reactors. 展开更多
关键词 Irradiation and corrosion Synergistic effect Austenitic stainless steels Nickel-based alloys Reactors
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DNA damage response-related immune activation signature predicts the response to immune checkpoint inhibitors: from gastrointestinal cancer analysis to pan-cancer validation
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作者 Junya Yan Shibo Wang +20 位作者 Jing Zhang Qiangqiang Yuan Xianchun Gao Nannan Zhang Yan Pan Haohao Zhang Kun liu Jun Yu Linbin Lu hui liu Xiaoliang Gao Sheng Zhao Wenyao Zhang Abudurousuli Reyila Yu Qi Qiujin Zhang Shundong Cang Yuanyuan Lu Yanglin Pan Yan Kong Yongzhan Nie 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第3期252-266,共15页
Objective: DNA damage response(DDR) deficiency has emerged as a prominent determinant of tumor immunogenicity. This study aimed to construct a DDR-related immune activation(DRIA) signature and evaluate the predictive ... Objective: DNA damage response(DDR) deficiency has emerged as a prominent determinant of tumor immunogenicity. This study aimed to construct a DDR-related immune activation(DRIA) signature and evaluate the predictive accuracy of the DRIA signature for response to immune checkpoint inhibitor(ICI) therapy in gastrointestinal(GI) cancer.Methods: A DRIA signature was established based on two previously reported DNA damage immune response assays. Clinical and gene expression data from two published GI cancer cohorts were used to assess and validate the association between the DRIA score and response to ICI therapy. The predictive accuracy of the DRIA score was validated based on one ICI-treated melanoma and three pan-cancer published cohorts.Results: The DRIA signature includes three genes(CXCL10, IDO1, and IFI44L). In the discovery cancer cohort, DRIA-high patients with gastric cancer achieved a higher response rate to ICI therapy than DRIA-low patients(81.8% vs. 8.8%;P < 0.001), and the predictive accuracy of the DRIA score [area under the receiver operating characteristic curve(AUC) = 0.845] was superior to the predictive accuracy of PD-L1 expression, tumor mutational burden, microsatellite instability, and Epstein–Barr virus status. The validation cohort demonstrated that the DRIA score identified responders with microsatellite-stable colorectal and pancreatic adenocarcinoma who received dual PD-1 and CTLA-4 blockade with radiation therapy. Furthermore, the predictive performance of the DRIA score was shown to be robust through an extended validation in melanoma, urothelial cancer, and pan-cancer.Conclusions: The DRIA signature has superior and robust predictive accuracy for the efficacy of ICI therapy in GI cancer and pancancer, indicating that the DRIA signature may serve as a powerful biomarker for guiding ICI therapy decisions. 展开更多
关键词 DNA damage response-related immune activation immune checkpoint inhibitors biomarker gastrointestinal cancer pan-cancer
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Elaidic acid-induced intestinal barrier damage led to gut-liver axis derangement and triggered NLRP3 inflammasome in the liver of SD rats
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作者 hui liu Xuenan Li +5 位作者 Lu Li Yucai Li Haiyang Yan Yong Pang Wenliang Li Yuan Yuan 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1279-1291,共13页
Previous studies have shown that trans fatty acids(TFA) are associated with several chronic diseases,the gut microbiota is directly influenced by dietary components and linked to chronic diseases.Our research investig... Previous studies have shown that trans fatty acids(TFA) are associated with several chronic diseases,the gut microbiota is directly influenced by dietary components and linked to chronic diseases.Our research investigated the effects of elaidic acid(EA),a typical TFA,on the gut microbiota to understand the underlying mechanisms of TFA-related chronic diseases.16S rDNA gene sequencing on faecal samples from Sprague-Dawley rats were performed to explore the composition change of the gut microbiota by EA gavage for 4 weeks.The results showed that the intake of EA increased the abundance of well-documented harmful bacteria,such as Proteobacteria,Anaerotruncus,Oscillibacter and Desulfovibrionaceae.Plus,EA induced translocation of lipopolysaccharides(LPS) and the above pathogenic bacteria,disrupted the intestinal barrier,led to gut-liver axis derangement and TLR4 pathway activation in the liver.Overall,EA induced intestinal barrier damage and regulated TLR4-MyD88-NF-κB/MAPK pathways in the liver of SD rats,leading to the activation of NLRP3 inflammasome and inflammatory liver damage. 展开更多
关键词 Elaidic acid(EA) Gut microbiota Intestinal barrier Gut-liver axis TLR4-MyD88-NF-κB/MAPK pathways NLRP3 inflammasome
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Data driven analysis reveals prognostic genes and immunological targets in human sepsis-associated acute kidney injury
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作者 Qing Zhao Jinfu Ma +2 位作者 Jianguo Xiao Zhe Feng hui liu 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第2期91-97,共7页
BACKGROUND:The molecular mechanism of sepsis-associated acute kidney injury(SA-AKI)is unclear.We analyzed co-differentially expressed genes(co-DEGs)to elucidate the underlying mechanism and intervention targets of SA-... BACKGROUND:The molecular mechanism of sepsis-associated acute kidney injury(SA-AKI)is unclear.We analyzed co-differentially expressed genes(co-DEGs)to elucidate the underlying mechanism and intervention targets of SA-AKI.METHODS:The microarray datasets GSE65682,GSE30718,and GSE174220 were downloaded from the Gene Expression Omnibus(GEO)database.We identified the co-DEGs and constructed a gene co-expression network to screen the hub genes.We analyzed immune correlations and disease correlations and performed functional annotation of the hub genes.We also performed single-cell and microenvironment analyses and investigated the enrichment pathways and the main transcription factors.Finally,we conducted a correlation analysis to evaluate the role of the hub genes.RESULTS:Interleukin 32(IL32)was identified as the hub gene in SA-AKI,and the main enriched signaling pathways were associated with hemopoiesis,cellular response to cytokine stimulus,inflammatory response,and regulation of kidney development.Additionally,IL32 was significantly associated with mortality in SA-AKI patients.Monocytes,macrophages,T cells,and NK cells were closely related to IL32 and were involved in the immune microenvironment in SA-AKI patients.IL32 expression increased significantly in the kidney of septic mouse.Toll-like receptor 2(TLR2)was significantly and negatively correlated with IL32.CONCLUSION:IL32 is the key gene involved in SA-AKI and is significantly associated with prognosis.TLR2 and relevant immune cells are closely related to key genes. 展开更多
关键词 SEPSIS Acute kidney injury Interleukin 32 Toll-like receptor 2 Bioinformatics analysis
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Proactive Caching at the Wireless Edge:A Novel Predictive User Popularity-Aware Approach
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作者 Yunye Wan Peng Chen +8 位作者 Yunni Xia Yong Ma Dongge Zhu Xu Wang hui liu Weiling Li Xianhua Niu Lei Xu Yumin Dong 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1997-2017,共21页
Mobile Edge Computing(MEC)is a promising technology that provides on-demand computing and efficient storage services as close to end users as possible.In an MEC environment,servers are deployed closer to mobile termin... Mobile Edge Computing(MEC)is a promising technology that provides on-demand computing and efficient storage services as close to end users as possible.In an MEC environment,servers are deployed closer to mobile terminals to exploit storage infrastructure,improve content delivery efficiency,and enhance user experience.However,due to the limited capacity of edge servers,it remains a significant challenge to meet the changing,time-varying,and customized needs for highly diversified content of users.Recently,techniques for caching content at the edge are becoming popular for addressing the above challenges.It is capable of filling the communication gap between the users and content providers while relieving pressure on remote cloud servers.However,existing static caching strategies are still inefficient in handling the dynamics of the time-varying popularity of content and meeting users’demands for highly diversified entity data.To address this challenge,we introduce a novel method for content caching over MEC,i.e.,PRIME.It synthesizes a content popularity prediction model,which takes users’stay time and their request traces as inputs,and a deep reinforcement learning model for yielding dynamic caching schedules.Experimental results demonstrate that PRIME,when tested upon the MovieLens 1M dataset for user request patterns and the Shanghai Telecom dataset for user mobility,outperforms its peers in terms of cache hit rates,transmission latency,and system cost. 展开更多
关键词 Mobile edge computing content caching system average cost deep reinforcement learning collaborative mechanism
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Performance optimization of the neutron-sensitive image intensifier used in neutron imaging
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作者 谭金昊 宋玉收 +14 位作者 周健荣 杨文钦 蒋兴奋 刘杰 张超月 周晓娟 夏远光 刘术林 闫保军 刘辉 王松林 赵豫斌 庄建 孙志嘉 陈元柏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期380-387,共8页
As a non-destructive testing technology,neutron imaging plays an important role in various fields,including material science,nuclear engineering,and fundamental science.An imaging detector with a neutron-sensitive ima... As a non-destructive testing technology,neutron imaging plays an important role in various fields,including material science,nuclear engineering,and fundamental science.An imaging detector with a neutron-sensitive image intensifier has been developed and demonstrated to achieve good spatial resolution and timing resolution.However,the influence of the working voltage on the performance of the neutron-sensitive imaging intensifier has not been studied.To optimize the performance of the neutron-sensitive image intensifier at different voltages,experiments have been performed at the China Spallation Neutron Source(CSNS)neutron beamline.The change in the light yield and imaging quality with different voltages has been acquired.It is shown that the image quality benefits from the high gain of the microchannel plate(MCP)and the high accelerating electric field between the MCP and the screen.Increasing the accelerating electric field is more effective than increasing the gain of MCPs for the improvement of the imaging quality.Increasing the total gain of the MCP stack can be realized more effectively by improving the gain of the standard MCP than that of the n MCP.These results offer a development direction for image intensifiers in the future. 展开更多
关键词 neutron detector neutron imaging microchannel plate image intensifier
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Semantic Segmentation and YOLO Detector over Aerial Vehicle Images
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作者 Asifa Mehmood Qureshi Abdul Haleem Butt +5 位作者 Abdulwahab Alazeb Naif Al Mudawi Mohammad Alonazi Nouf Abdullah Almujally Ahmad Jalal hui liu 《Computers, Materials & Continua》 SCIE EI 2024年第8期3315-3332,共18页
Intelligent vehicle tracking and detection are crucial tasks in the realm of highway management.However,vehicles come in a range of sizes,which is challenging to detect,affecting the traffic monitoring system’s overa... Intelligent vehicle tracking and detection are crucial tasks in the realm of highway management.However,vehicles come in a range of sizes,which is challenging to detect,affecting the traffic monitoring system’s overall accuracy.Deep learning is considered to be an efficient method for object detection in vision-based systems.In this paper,we proposed a vision-based vehicle detection and tracking system based on a You Look Only Once version 5(YOLOv5)detector combined with a segmentation technique.The model consists of six steps.In the first step,all the extracted traffic sequence images are subjected to pre-processing to remove noise and enhance the contrast level of the images.These pre-processed images are segmented by labelling each pixel to extract the uniform regions to aid the detection phase.A single-stage detector YOLOv5 is used to detect and locate vehicles in images.Each detection was exposed to Speeded Up Robust Feature(SURF)feature extraction to track multiple vehicles.Based on this,a unique number is assigned to each vehicle to easily locate them in the succeeding image frames by extracting them using the feature-matching technique.Further,we implemented a Kalman filter to track multiple vehicles.In the end,the vehicle path is estimated by using the centroid points of the rectangular bounding box predicted by the tracking algorithm.The experimental results and comparison reveal that our proposed vehicle detection and tracking system outperformed other state-of-the-art systems.The proposed implemented system provided 94.1%detection precision for Roundabout and 96.1%detection precision for Vehicle Aerial Imaging from Drone(VAID)datasets,respectively. 展开更多
关键词 Semantic segmentation YOLOv5 vehicle detection and tracking Kalman filter SURF
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Knockout of C6orf120 in Rats Alleviates Concanavalin A-induced Autoimmune Hepatitis by Regulating Macrophage Polarization
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作者 Xin Wang Yuqi Wang +4 位作者 hui liu Yingying Lin Peng Wang Yunyun Yi Xin Li 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第6期594-606,共13页
Objective The effect of the functionally unknown gene C6orf120 on autoimmune hepatitis was investigated on C6orf120 knockout rats(C6orf120^(-/-))and THP-1 cells.Method Six–eight-week-old C6orf120^(-/-)and wild-type(W... Objective The effect of the functionally unknown gene C6orf120 on autoimmune hepatitis was investigated on C6orf120 knockout rats(C6orf120^(-/-))and THP-1 cells.Method Six–eight-week-old C6orf120^(-/-)and wild-type(WT)SD rats were injected with Con A(16 mg/kg),and euthanized after 24 h.The sera,livers,and spleens were collected.THP-1 cells and the recombinant protein(rC6ORF120)were used to explore the mechanism in vitro.The frequency of M1 and M2 macrophages was analyzed using flow cytometry.Western blotting and PCR were used to detect macrophage polarization-associated factors.Results C6orf120 knockout attenuated Con A-induced autoimmune hepatitis.Flow cytometry indicated that the proportion of CD68^(+)CD86^(+)M1 macrophages from the liver and spleen in the C6orf120^(-/-)rats decreased.C6orf120 knockout induced downregulation of CD86 protein and the mRNA levels of related inflammatory factors TNF-α,IL-1β,and IL-6 in the liver.C6orf120 knockout did not affect the polarization of THP-1 cells.However,rC6ORF120 promoted the THP-1 cells toward CD68^(+)CD80^(+)M1 macrophages and inhibited the CD68^(+)CD206^(+)M2 phenotype.Conclusion C6orf120 knockout alleviates Con A-induced autoimmune hepatitis by inhibiting macrophage polarization toward M1 macrophages and reducing the expression of related inflammatory factors in C6orf120^(-/-)rats. 展开更多
关键词 C6orf120 Autoimmune hepatitis Macrophage polarization M1 macrophages
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Resolution Enhancement of SOHO/MDI Magnetograms
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作者 Ying Qin Kai-Fan Ji +1 位作者 hui liu Xiao-Guang Yu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期358-367,共10页
Research on the solar magnetic field and its effects on solar dynamo mechanisms and space weather events has benefited from the continual improvements in instrument resolution and measurement frequency.The augmentatio... Research on the solar magnetic field and its effects on solar dynamo mechanisms and space weather events has benefited from the continual improvements in instrument resolution and measurement frequency.The augmentation and assimilation of historical observational data timelines also play a significant role in understanding the patterns of solar magnetic field variation.Within the realm of astronomical data processing,super-resolution(SR)reconstruction refers to the process of using a substantial corpus of training data to learn the nonlinear mapping between low-resolution(LR)and high-resolution(HR)images,thereby achieving higherresolution astronomical images.This paper is an application study in high-dimensional nonlinear regression.Deep learning models were employed to perform SR modeling on SOHO/MDI magnetograms and SDO/HMI magnetograms,thus reliably achieving resolution enhancement of full-disk SOHO/MDI magnetograms and enhancing the image resolution to obtain more detailed information.For this study,a data set comprising 9717pairs of data from 2010 April to 2011 February was used as the training set,1332 pairs from 2011 March were used as the validation set and 1034 pairs from 2011 April were used as the test set.After data preprocessing,we randomly cropped 128×128 sub-images as the LR cases from the full-disk MDI magnetograms,and the corresponding 512×512 sub-images as HR ones from the HMI full-disk magnetograms for model training.The tests conducted have shown that the study successfully produced reliable 4×SR reconstruction of full-disk MDI magnetograms.The MESR model's results(0.911)were highly correlated with the target HMI magnetographs as indicated by the correlation coefficient values.Furthermore,the method achieved the best PSNR,SSIM,MAE and RMSE values,indicating that the MESR model can effectively reconstruct magnetograms. 展开更多
关键词 magnetic fields techniques:image processing virtual observatory tools Sun:magnetic fields
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Retinal vascular morphological characteristics in diabetic retinopathy: an artificial intelligence study using a transfer learning system to analyze ultra-wide field images
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作者 Xin-Yi Deng hui liu +6 位作者 Zheng-Xi Zhang Han-Xiao Li Jun Wang Yi-Qi Chen Jian-Bo Mao Ming-Zhai Sun Li-Jun Shen 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第6期1001-1006,共6页
AIM:To investigate the morphological characteristics of retinal vessels in patients with different severity of diabetic retinopathy(DR)and in patients with or without diabetic macular edema(DME).METHODS:The 239 eyes o... AIM:To investigate the morphological characteristics of retinal vessels in patients with different severity of diabetic retinopathy(DR)and in patients with or without diabetic macular edema(DME).METHODS:The 239 eyes of DR patients and 100 eyes of healthy individuals were recruited for the study.The severity of DR patients was graded as mild,moderate and severe non-proliferative diabetic retinopathy(NPDR)according to the international clinical diabetic retinopathy(ICDR)disease severity scale classification,and retinal vascular morphology was quantitatively analyzed in ultra-wide field images using RU-net and transfer learning methods.The presence of DME was determined by optical coherence tomography(OCT),and differences in vascular morphological characteristics were compared between patients with and without DME.RESULTS:Retinal vessel segmentation using RU-net and transfer learning system had an accuracy of 99%and a Dice metric of 0.76.Compared with the healthy group,the DR group had smaller vessel angles(33.68±3.01 vs 37.78±1.60),smaller fractal dimension(Df)values(1.33±0.05 vs 1.41±0.03),less vessel density(1.12±0.44 vs 2.09±0.36)and fewer vascular branches(206.1±88.8 vs 396.5±91.3),all P<0.001.As the severity of DR increased,Df values decreased,P=0.031.No significant difference between the DME and non-DME groups were observed in vascular morphological characteristics.CONCLUSION:In this study,an artificial intelligence retinal vessel segmentation system is used with 99%accuracy,thus providing with relatively satisfactory performance in the evaluation of quantitative vascular morphology.DR patients have a tendency of vascular occlusion and dropout.The presence of DME does not compromise the integral retinal vascular pattern. 展开更多
关键词 diabetic retinopathy vascular morphology deep learning ultra-wide field imaging diabetic macular edema
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Localization method of subsynchronous oscillation source based on high-resolution time-frequency distribution image and CNN
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作者 hui liu Yundan Cheng +3 位作者 Yanhui Xu Guanqun Sun Rusi Chen Xiaodong Yu 《Global Energy Interconnection》 EI CSCD 2024年第1期1-13,共13页
The penetration of new energy sources such as wind power is increasing,which consequently increases the occurrence rate of subsynchronous oscillation events.However,existing subsynchronous oscillation source-identific... The penetration of new energy sources such as wind power is increasing,which consequently increases the occurrence rate of subsynchronous oscillation events.However,existing subsynchronous oscillation source-identification methods primarily analyze fixed-mode oscillations and rarely consider time-varying features,such as frequency drift,caused by the random volatility of wind farms when oscillations occur.This paper proposes a subsynchronous oscillation sourcelocalization method that involves an enhanced short-time Fourier transform and a convolutional neural network(CNN).First,an enhanced STFT is performed to secure high-resolution time-frequency distribution(TFD)images from the measured data of the generation unit ports.Next,these TFD images are amalgamated to form a subsynchronous oscillation feature map that serves as input to the CNN to train the localization model.Ultimately,the trained CNN model realizes the online localization of subsynchronous oscillation sources.The effectiveness and accuracy of the proposed method are validated via multimachine system models simulating forced and natural oscillation events using the Power Systems Computer Aided Design platform.Test results show that the proposed method can localize subsynchronous oscillation sources online while considering unpredictable fluctuations in wind farms,thus providing a foundation for oscillation suppression in practical engineering scenarios. 展开更多
关键词 Subsynchronous oscillation source localization Synchronous squeezing transform Enhanced short-time Fourier transform Convolutional neural networks
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Gradient coil design with enhanced shielding constraint for a cryogen-free superconducting MRI system
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作者 Yaohui Wang Weimin Wang +3 位作者 hui liu Shunzhong Chen Feng liu Qiuliang Wang 《Magnetic Resonance Letters》 2024年第1期1-9,共9页
The relatively fragile low-temperature stability of cryogen-free superconducting magnetic resonance imaging(MRI)magnets requires the careful management of exogenous heat sources.A strongly shielded gradient magnetic f... The relatively fragile low-temperature stability of cryogen-free superconducting magnetic resonance imaging(MRI)magnets requires the careful management of exogenous heat sources.A strongly shielded gradient magnetic field is important for the optimal operation of cryogen-free MRI systems.In this study,we present an enhanced shielding method incorporating a regionalized stray field constraining strategy.By optimizing the constraint parameters,we could develop engineering-feasible gradient coil schemes without increasing system complexity but with the stray field intensity reduced by half.In real measurement in an integrated MRI system,the developed gradient assembly demonstrated good performance and supported to output images of excellent quality.Our findings suggested that the proposed method could potentially form a useful design paradigm for cryogen-free MRI magnets. 展开更多
关键词 MRI Gradient coil Superconducting magnet Cryogen-free Magnetic shielding
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Decoupling of Rattling Mode and Superconductivity in Filled-Skutterudite Ba_(x)Ir_(4)Sb_(12)
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作者 刘辉 于同旭 +1 位作者 张志华 应天平 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第7期132-139,共8页
The rattling mode,an anharmonic vibrational phonon,is widely recognized as a critical factor in the emergence of superconductivity in caged materials.Here,we present a counterexample in a filled-skutterudite supercond... The rattling mode,an anharmonic vibrational phonon,is widely recognized as a critical factor in the emergence of superconductivity in caged materials.Here,we present a counterexample in a filled-skutterudite superconductor Ba_(x)Ir_(4)Sb_(12)(x=0.8,0.9,1.0),synthesized via a high-pressure route.Transport measurements down to liquid 3He temperatures reveal a transition temperature(T_(c))of 1.2 K and an upper critical field(H_(c2))of 1.3 T.Unlike other superconductors with caged structures,the Ba_(x)Ir_(4)Sb_(12)(X=P,As,Sb)family exhibits a monotonic decreasing T_(c) with the enhancement of the rattling mode,as indicated by fitting the Bloch–Grüneisen formula.Theoretical analysis suggests that electron doping from Ba transforms the direct bandgap IrSb3 into a metal,with the Fermi surface dominated by the hybridization of Ir 5d and Sb 5p orbitals.Our findings of decoupled rattling modes and superconductivity distinguish the Ba_(x)Ir_(4)Sb_(12) family from other caged superconductors,warranting further exploration into the underlying mechanism. 展开更多
关键词 mechanism materials SUPERCONDUCTIVITY
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Influence of the position relationship between the cathode and magnetic separatrix on the discharge process of a Hall thruster
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作者 曹希峰 麻洪宁 +4 位作者 夏国俊 刘辉 赵方舟 王宇航 陈巨辉 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第1期74-81,共8页
Previous studies have shown that there is an obvious coupling relationship between the installation location of the external cathode and the magnetic separatrix in the plume region of a Hall thruster.In this paper,the... Previous studies have shown that there is an obvious coupling relationship between the installation location of the external cathode and the magnetic separatrix in the plume region of a Hall thruster.In this paper,the particle-in-cell simulation method is used to compare the thruster discharge process under the conditions of different position relationships between the cathode and the magnetic separatrix.By comparing the distribution of electron conduction,potential,plasma density and other microscopic parameters,we try to explain the formation mechanism of the discharge difference.The simulation results show that the cathode inside and outside the magnetic separatrix has a significant effect on the distribution of potential and plasma density.When the cathode is located on the outer side of the magnetic separatrix,the potential above the plume region is relatively low,and there is a strong potential gradient above the plume region.This potential gradient is more conducive to the radial diffusion of ions above the plume,which is the main reason for the strong divergence of the plume.The distribution of ion density is also consistent with the distribution of potential.When the cathode is located on the outer side of the magnetic separatrix,the radial diffusion of ions in the plume region is enhanced.Meanwhile,by comparing the results of electron conduction,it is found that the traiectories of electrons emitted from the cathode are significantly different between the inner and outer sides of the magnetic separatrix.This is mainly because the electrons are affected by the magnetic mirror effect of the magnetic tip,which makes it difficult for the electrons to move across the magnetic separatrix.This is the main reason for the difference in potential distribution.In this paper,the simulation results of macroscopic parameters under several conditions are also compared,and they are consistent with the experimental results.The cathode is located on the inner side of the magnetic separatrix,which can effectively reduce the plume divergence angle and improve the thrust.In this paper,the cathode moves from R=50 mm to R=35 mm along the radial direction,the thrust increases by 3.6 mN and the plume divergence angle decreases by 23.77%.Combined with the comparison of the ionization region and the peak ion density,it is found that the main reason for the change in thrust is the change in the radial diffusion of ions in the plume region. 展开更多
关键词 Hall thruster CATHODE magnetic separatrix
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iTRAQ-based proteomics reveals the mechanism of action of Yinlai decoction in treating pneumonia in mice consuming a high-calorie diet
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作者 Qianqian Li Tiegang liu +7 位作者 Chen Bai Xueyan Ma hui liu Zi’an Zheng Yuxiang Wan He Yu Yuling Ma Xiaohong Gu 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第1期21-32,共12页
Objective:To uncover the underlying mechanisms of action of the Yinlai decoction on high-calorie dietinduced pneumonia through proteomics analysis.Methods:Based on the Gene Expression Omnibus(GEO)database,lung tissue ... Objective:To uncover the underlying mechanisms of action of the Yinlai decoction on high-calorie dietinduced pneumonia through proteomics analysis.Methods:Based on the Gene Expression Omnibus(GEO)database,lung tissue samples from normal and high-fat diet(HFD)fed mice in the GSE16377 dataset were selected as test cohorts to identify differentially expressed genes and conduct bioinformatics analyses.In the animal experiments,mice were randomly divided into the control(N),high-calorie diet pneumonia(M),and Yinlai decoction treatment(Y)groups.Mice in the M group received high-calorie feed and a 0.5 mg/mL lipopolysaccharide solution spray for 30 min for 3 d.The mice in the Y group were intragastrically administered 2 mL/10 g Yinlai decoction twice daily for 3 d.Pathological evaluation of the lung tissue was performed.Differentially expressed proteins(DEPs)in the lung tissue were identified using quantitative proteomics and bioinformatics analyses.The drug-target relationships between Yinlai decoction and core DEPs in the lung tissue were verified using AutoDock Vina and Molecular Graphics Laboratory(MGL)Tools.DEPs were verified by western blot.Results:GEO data mining showed that an HFD altered oxidative phosphorylation in mouse lung tissue.The Yinlai decoction alleviated pathological damage to lung tissue and pneumonia in mice that were fed a high-calorie diet.A total of 47 DEPs were identified between the Y and M groups.Enrichment analysis revealed their association with energy metabolism pathways such as the tricarboxylic acid cycle(TCA)and oxidative phosphorylation.The protein-protein interaction network revealed that Atp5a1,Pdha1,and Sdha were the target proteins mediating the therapeutic effects of Yinlai decoction.Molecular docking results suggested that the mechanism of the therapeutic effect of Yinlai decoction involves the binding of brassinolide,praeruptorin B,chrysoeriol,and other components in Yinlai decoction to Atp5a1.Conclusion:The Yinlai decoction alleviated lung tissue damage and pneumonia in mice that were fed a high-calorie diet by regulating the TCA and oxidative phosphorylation.Our study highlights the importance of a healthy diet for patients with pneumonia and provides a scientific basis for the prevention and treatment of pneumonia through dietary adjustments. 展开更多
关键词 Yinlai decoction High-calorie diet PNEUMONIA iTRAQ proteomics Energy metabolism
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