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融合MacBERT和Talking⁃Heads Attention实体关系联合抽取模型
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作者 王春亮 姚洁仪 李昭 《现代电子技术》 北大核心 2024年第5期127-131,共5页
针对现有的医学文本关系抽取任务模型在训练过程中存在语义理解能力不足,可能导致关系抽取的效果不尽人意的问题,文中提出一种融合MacBERT和Talking⁃Heads Attention的实体关系联合抽取模型。该模型首先利用MacBERT语言模型来获取动态... 针对现有的医学文本关系抽取任务模型在训练过程中存在语义理解能力不足,可能导致关系抽取的效果不尽人意的问题,文中提出一种融合MacBERT和Talking⁃Heads Attention的实体关系联合抽取模型。该模型首先利用MacBERT语言模型来获取动态字向量表达,MacBERT作为改进的BERT模型,能够减少预训练和微调阶段之间的差异,从而提高模型的泛化能力;然后,将这些动态字向量表达输入到双向门控循环单元(BiGRU)中,以便提取文本的上下文特征。BiGRU是一种改进的循环神经网络(RNN),具有更好的长期依赖捕获能力。在获取文本上下文特征之后,使用Talking⁃Heads Attention来获取全局特征。Talking⁃Heads Attention是一种自注意力机制,可以捕获文本中不同位置之间的关系,从而提高关系抽取的准确性。实验结果表明,与实体关系联合抽取模型GRTE相比,该模型F1值提升1%,precision值提升0.4%,recall值提升1.5%。 展开更多
关键词 MacBERT BiGRU 关系抽取 医学文本 talking⁃heads Attention 深度学习 全局特征 神经网络
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基于Viseme的连续语音识别系统及Talking Head 被引量:2
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作者 蒋冬梅 谢磊 +3 位作者 Ilse Ravyse 赵荣椿 Hichem Sahli Jan Cornelis 《电子与信息学报》 EI CSCD 北大核心 2004年第3期375-381,共7页
为实现听觉/视觉驱动的说话人头部动画,该文给出了一个基于viseme(说话时的基本嘴形单位)的连续语音识别系统。它训练viseme隐马尔可夫模型(HMM),识别语音为viseme图像序列。建模采用triseme的概念来考虑viseme的上下文相关性,但它需要... 为实现听觉/视觉驱动的说话人头部动画,该文给出了一个基于viseme(说话时的基本嘴形单位)的连续语音识别系统。它训练viseme隐马尔可夫模型(HMM),识别语音为viseme图像序列。建模采用triseme的概念来考虑viseme的上下文相关性,但它需要超大量的训练数据。该文根据viseme图像及其相似度权值(VSW)定义视觉问题集,用来建立triseme决策树,以实现triseme的状态捆绑及HMM参数共享。为比较系统性能,基于phoneme(听觉领域的语音基本单位)的语音识别结果也被映射为viseme序列。在评价准则上,定义viseme图像相似度加权识别精度,更全面地考虑输出和参考图像序列的差别,并用嘴形圆度和VSW曲线中的突变点来评估所得viseme序列的平滑性。结果表明,基于viseme的语音识别系统能给出更平滑和合理的嘴形图像序列。 展开更多
关键词 说话人头部动画 Viseme 连续语音识别 Triseme决策树 图像相似度加权 嘴形圆度
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A Cooperative Security Monitoring Mechanism Aided by Optimal Multiple Slave Cluster Heads for UASNs
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作者 Yougan Chen Wei Wang +3 位作者 Xiang Sun Yi Tao Zhenwen Liu Xiaomei Xu 《China Communications》 SCIE CSCD 2023年第5期148-169,共22页
As each cluster head(CH)sensor node is used to aggregate,fuse,and forward data from different sensor nodes in an underwater acoustic sensor network(UASN),guaranteeing the data security in a CH is very critical.In this... As each cluster head(CH)sensor node is used to aggregate,fuse,and forward data from different sensor nodes in an underwater acoustic sensor network(UASN),guaranteeing the data security in a CH is very critical.In this paper,a cooperative security monitoring mechanism aided by multiple slave cluster heads(SCHs)is proposed to keep track of the data security of a CH.By designing a low complexity“equilateral triangle algorithm(ETA)”,the optimal SCHs(named as ETA-based multiple SCHs)are selected from the candidate SCHs so as to improve the dispersion and coverage of SCHs and achieve largescale data security monitoring.In addition,by analyzing the entire monitoring process,the close form expression of the probability of the failure attack identification for the SCHs with respect to the probability of attack launched by ordinary nodes is deduced.The simulation results show that the proposed optimal ETA-based multiple SCH cooperation scheme has lower probability of the failure attack identification than that of the existing schemes.In addition,the numerical simulation results are consistent with the theoretical analysis results,thus verifying the effectiveness of the proposed scheme. 展开更多
关键词 underwater acoustic sensor networks data security cluster head nodes optimal location distribution of multiple slave cluster head nodes
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Long non-coding RNA H19 regulates neurogenesis of induced neural stem cells in a mouse model of closed head injury 被引量:1
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作者 Mou Gao Qin Dong +4 位作者 Zhijun Yang Dan Zou Yajuan Han Zhanfeng Chen Ruxiang Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期872-880,共9页
Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regen... Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regeneration via cell replacement.However,the neural regeneration efficiency of induced neural stem cells remains limited.In this study,we explored differentially expressed genes and long non-coding RNAs to clarify the mechanism underlying the neurogenesis of induced neural stem cells.We found that H19 was the most downregulated neurogenesis-associated lnc RNA in induced neural stem cells compared with induced pluripotent stem cells.Additionally,we demonstrated that H19 levels in induced neural stem cells were markedly lower than those in induced pluripotent stem cells and were substantially higher than those in induced neural stem cell-derived neurons.We predicted the target genes of H19 and discovered that H19 directly interacts with mi R-325-3p,which directly interacts with Ctbp2 in induced pluripotent stem cells and induced neural stem cells.Silencing H19 or Ctbp2 impaired induced neural stem cell proliferation,and mi R-325-3p suppression restored the effect of H19 inhibition but not the effect of Ctbp2 inhibition.Furthermore,H19 silencing substantially promoted the neural differentiation of induced neural stem cells and did not induce apoptosis of induced neural stem cells.Notably,silencing H19 in induced neural stem cell grafts markedly accelerated the neurological recovery of closed head injury mice.Our results reveal that H19 regulates the neurogenesis of induced neural stem cells.H19 inhibition may promote the neural differentiation of induced neural stem cells,which is closely associated with neurological recovery following closed head injury. 展开更多
关键词 closed head injury Ctbp2 induced neural stem cell lncRNA H19 miR-325-3p NEUROGENESIS
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Knowledge, Attitude, and Practice of Using Helmets in Children amongst Parents to Prevent Head Injuries: A Cross-Sectional Study in Riyadh, Saudi Arabia
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作者 Turki Salah Aldeen Bukhari Abdullah Yahya Aldhban +4 位作者 Anas Abdulrahman Alqasem Dona Jamal Al Hatlani Hareth Aldosaimani Hamad A. Al Madi Khalid Alqahtani 《Open Journal of Pediatrics》 2024年第2期255-265,共11页
Objectives: The primary objective was to characterize the range of Knowledge, Attitude, and Practice (KAP) of Helmet use in children amongst parents to prevent head injuries and death. Methods: This is a cross-section... Objectives: The primary objective was to characterize the range of Knowledge, Attitude, and Practice (KAP) of Helmet use in children amongst parents to prevent head injuries and death. Methods: This is a cross-sectional study, done by online survey using a snowball sampling technique, the number of included responses were 386 parents (Male and female) living in Riyadh Aged 21 - 60 years old or above. Results: The study showed that there is a difference in Parents’ belief in the importance of helmet use while riding a Bicycle vs Motorcycle/Quad bike and that was affected by parents’ education level, almost all the people who answered the survey (76.7%) agree that it is important for their children to wear a helmet when riding both a Bicycle and a Motorcycle or Quadbike with a cumulative percentage of (93.8%). And almost all agreed on multiple approaches to help increase helmet use be it by forcing rental shops to give out helmets, forcing sellers to recommend the use of helmets, increasing awareness campaigns, and imposing fines for not wearing helmets. Conclusions: This study is the first to explore Family helmet use while riding Bicycles and Motorcycles/Quad bikes. Although Parent’s belief in the importance of helmet use for their children was high, it is clear that the level of practice is low. With that the risk of head injuries might be high, our findings suggest that safety interventions for increasing pediatric helmet use are needed to increase helmet use and reduce the risk of head injury and hospitalization. 展开更多
关键词 head Trauma head Injury Helmet Bicycle Motorcycle Quad Bike KAP Knowledge ATTITUDE PRACTICE
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Basal defense is enhanced in a wheat cultivar resistant to Fusarium head blight
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作者 Xinlong Gao Fan Li +7 位作者 Yikun Sun Jiaqi Jiang Xiaolin Tian Qingwen Li Kaili Duan Jie Lin Huiquan Liu Qinhu Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1238-1258,共21页
Fusarium head blight(FHB),mainly caused by the fungal pathogen Fusarium graminearum,is one of the most destructive wheat diseases.Besides directly affecting the yield,the mycotoxin residing in the kernel greatly threa... Fusarium head blight(FHB),mainly caused by the fungal pathogen Fusarium graminearum,is one of the most destructive wheat diseases.Besides directly affecting the yield,the mycotoxin residing in the kernel greatly threatens the health of humans and livestock.Xinong 979(XN979)is a widely cultivated wheat elite with high yield and FHB resistance.However,its resistance mechanism remains unclear.In this study,we studied the expression of genes involved in plant defense in XN979 by comparative transcriptomics.We found that the FHB resistance in XN979 consists of two lines of defense.The first line of defense,which is constitutive,is knitted via the enhanced basal expression of lignin and jasmonic acid(JA)biosynthesis genes.The second line of defense,which is induced upon F.graminearum infection,is contributed by the limited suppression of photosynthesis and the struggle of biotic stress-responding genes.Meanwhile,the effective defense in XN979 leads to an inhibition of fungal gene expression,especially in the early infection stage.The formation of the FHB resistance in XN979 may coincide with the breeding strategies,such as selecting high grain yield and lodging resistance traits.This study will facilitate our understanding of wheat-F.graminearum interaction and is insightful for breeding FHB-resistant wheat. 展开更多
关键词 Fusarium head blight Xinong 979 LIGNIN jasmonic acid PHOTOSYNTHESIS Fusarium graminearum
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YOLO-MFD:Remote Sensing Image Object Detection with Multi-Scale Fusion Dynamic Head
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作者 Zhongyuan Zhang Wenqiu Zhu 《Computers, Materials & Continua》 SCIE EI 2024年第5期2547-2563,共17页
Remote sensing imagery,due to its high altitude,presents inherent challenges characterized by multiple scales,limited target areas,and intricate backgrounds.These inherent traits often lead to increased miss and false... Remote sensing imagery,due to its high altitude,presents inherent challenges characterized by multiple scales,limited target areas,and intricate backgrounds.These inherent traits often lead to increased miss and false detection rates when applying object recognition algorithms tailored for remote sensing imagery.Additionally,these complexities contribute to inaccuracies in target localization and hinder precise target categorization.This paper addresses these challenges by proposing a solution:The YOLO-MFD model(YOLO-MFD:Remote Sensing Image Object Detection withMulti-scale Fusion Dynamic Head).Before presenting our method,we delve into the prevalent issues faced in remote sensing imagery analysis.Specifically,we emphasize the struggles of existing object recognition algorithms in comprehensively capturing critical image features amidst varying scales and complex backgrounds.To resolve these issues,we introduce a novel approach.First,we propose the implementation of a lightweight multi-scale module called CEF.This module significantly improves the model’s ability to comprehensively capture important image features by merging multi-scale feature information.It effectively addresses the issues of missed detection and mistaken alarms that are common in remote sensing imagery.Second,an additional layer of small target detection heads is added,and a residual link is established with the higher-level feature extraction module in the backbone section.This allows the model to incorporate shallower information,significantly improving the accuracy of target localization in remotely sensed images.Finally,a dynamic head attentionmechanism is introduced.This allows themodel to exhibit greater flexibility and accuracy in recognizing shapes and targets of different sizes.Consequently,the precision of object detection is significantly improved.The trial results show that the YOLO-MFD model shows improvements of 6.3%,3.5%,and 2.5%over the original YOLOv8 model in Precision,map@0.5 and map@0.5:0.95,separately.These results illustrate the clear advantages of the method. 展开更多
关键词 Object detection YOLOv8 MULTI-SCALE attention mechanism dynamic detection head
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A Dual-Cluster-Head Based Medium Access Control for Large-Scale UAV Ad-Hoc Networks
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作者 Zhao Xinru Wei Zhiqing +3 位作者 Zou Yingying Ma Hao Cui Yanpeng Feng Zhiyong 《China Communications》 SCIE CSCD 2024年第5期123-136,共14页
Unmanned Aerial Vehicle(UAV)ad hoc network has achieved significant growth for its flexibility,extensibility,and high deployability in recent years.The application of clustering scheme for UAV ad hoc network is impera... Unmanned Aerial Vehicle(UAV)ad hoc network has achieved significant growth for its flexibility,extensibility,and high deployability in recent years.The application of clustering scheme for UAV ad hoc network is imperative to enhance the performance of throughput and energy efficiency.In conventional clustering scheme,a single cluster head(CH)is always assigned in each cluster.However,this method has some weaknesses such as overload and premature death of CH when the number of UAVs increased.In order to solve this problem,we propose a dual-cluster-head based medium access control(DCHMAC)scheme for large-scale UAV networks.In DCHMAC,two CHs are elected to manage resource allocation and data forwarding cooperatively.Specifically,two CHs work on different channels.One of CH is used for intra-cluster communication and the other one is for inter-cluster communication.A Markov chain model is developed to analyse the throughput of the network.Simulation result shows that compared with FM-MAC(flying ad hoc networks multi-channel MAC,FM-MAC),DCHMAC improves the throughput by approximately 20%~50%and prolongs the network lifetime by approximately 40%. 展开更多
关键词 dual cluster head medium access control UAV swarm
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Surgical Treatment of Osteonecrosis of the Femoral Head Using Minimally Invasive Surgical Drilling and Cancellous Grafting at Brazzaville University Hospital
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作者 Kevin Parfait Bienvenu Bouhelo-Pam Marius Monka +4 位作者 Arnauld Sledje Wilfrid Bilongo Bouyou Regis Perry Massouama Paul Yèlai Ikounga Roger Bertrand Sah Mbou Armand Moyikoua 《Open Journal of Orthopedics》 2024年第2期122-132,共11页
Introduction: Osteonecrosis of the femoral head (ONTF) is a debilitating condition. Several treatments have been proposed with controversial results. The aim of our study was to evaluate treatment by surgical drilling... Introduction: Osteonecrosis of the femoral head (ONTF) is a debilitating condition. Several treatments have been proposed with controversial results. The aim of our study was to evaluate treatment by surgical drilling coupled with in situ cancellous grafting. Materials and methods: Our study was a case-control study conducted at Brazzaville University Hospital from 1st January 2018 to 31 December 2023. It compared two groups of patients with ONTF: non-operated (13 patients, 20 hips) and operated (22 patients, 35 hips). We used the visual digital scale (VDS) for pain assessment, the Merle D’Aubigne-Postel (MDP) scoring system for clinical and functional assessment, and the evolution of necrosis. Results: The group of non-operated patients had a mean age of 35.69 ± 3.4 years, no improvement in pain with an EVN above seven at the last recoil and a mean global MDP score falling from 12.7 before offloading to 10.13 at one year. The group of patients operated on had a mean age of 37.86 ± 7.02 years, a significant reduction in pain (p = 0.00004) and a significantly increased MDP score (p = 0.0034). A comparison of the two groups of patients showed significant stabilization of the necrotic lesions in the operated patients (p = 0.00067), with better satisfaction in the same group. Conclusion: Surgical drilling combined with grafting in the treatment of early-stage ONTF has improved progress in our series. The technique is reproducible and less invasive. It has made it possible to delay unfavorable progression and, consequently, hip replacement surgery. 展开更多
关键词 HIP Osteonecrosis of the Femoral head Conservative Treatment Surgical Drilling Bone Grafting
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Fetal Head Compression: Its Possible Role in Neurologic Injury
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作者 Barry S. Schifrin Brian J. Koos Wayne R. Cohen 《Open Journal of Obstetrics and Gynecology》 2024年第1期124-143,共20页
It is widely assumed that fetal ischemic brain injury during labor derives almost exclusively from severe, systemic hypoxemia with marked neonatal depression and acidemia. Severe asphyxia, however, is one of several c... It is widely assumed that fetal ischemic brain injury during labor derives almost exclusively from severe, systemic hypoxemia with marked neonatal depression and acidemia. Severe asphyxia, however, is one of several causes of perinatal neurological injury and may not be the most common;most neonates diagnosed with hypoxic-ischemic encephalopathy do not have evidence of severe asphyxia. Sepsis, direct brain trauma, and drug or toxin exposure account for some cases, while mechanical forces of labor and delivery that increase fetal intracranial pressure sufficiently to impair brain perfusion may also contribute. Because of bony compliance and mobile suture lines, the fetal skull changes shape and redistributes cerebrospinal fluid during labor according to constraints imposed by contractions, and bony and soft tissue elements of the birth canal as the head descends. These accommodations, including the increase in intracranial pressure, are adaptive and necessary for efficient descent of the head while safeguarding cerebral blood flow. Autonomic reflexes mediated through central receptors normally provide ample protection of the brain from the considerable pressure exerted on the skull. On occasion, those forces, which are transmitted intracranially, may overcome the various adaptive anatomical, cardiovascular, metabolic, and neurological mechanisms that maintain cerebral perfusion and oxygen availability, resulting in ischemic brain injury. Accepting the notion of a potentially adverse impact of fetal head compression suggests that avoidance of excessive uterine activity and of relentless pushing without steady progress in descent may offer protection for the fetal brain during parturition. Excessive head compression should be considered in the differential diagnosis of ischemic encephalopathy. 展开更多
关键词 Fetal Brain Injury Fetal head Compression Ischemic Encephalopathy Neonatal Encephalopathy
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New perspectives on biology,disease progression,and therapy response of head and neck cancer gained from single cell RNA sequencing and spatial transcriptomics
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作者 GERWIN HELLER THORSTEN FUEREDER +1 位作者 ALEXANDER MICHAEL GRANDITS ROTRAUD WIESER 《Oncology Research》 SCIE 2024年第1期1-17,共17页
Head and neck squamous cell carcinoma(HNSCC)is one of the most frequent cancers worldwide.The main risk factors are consumption of tobacco products and alcohol,as well as infection with human papilloma virus.Approved ... Head and neck squamous cell carcinoma(HNSCC)is one of the most frequent cancers worldwide.The main risk factors are consumption of tobacco products and alcohol,as well as infection with human papilloma virus.Approved therapeutic options comprise surgery,radiation,chemotherapy,targeted therapy through epidermal growth factor receptor inhibition,and immunotherapy,but outcome has remained unsatisfactory due to recurrence rates of~50%and the frequent occurrence of second primaries.The availability of the human genome sequence at the beginning of the millennium heralded the omics era,in which rapid technological progress has advanced our knowledge of the molecular biology of malignant diseases,including HNSCC,at an unprecedented pace.Initially,microarray-based methods,followed by approaches based on next-generation sequencing,were applied to study the genetics,epigenetics,and gene expression patterns of bulk tumors.More recently,the advent of single-cell RNA sequencing(scRNAseq)and spatial transcriptomics methods has facilitated the investigation of the heterogeneity between and within different cell populations in the tumor microenvironment(e.g.,cancer cells,fibroblasts,immune cells,endothelial cells),led to the discovery of novel cell types,and advanced the discovery of cell-cell communication within tumors.This review provides an overview of scRNAseq,spatial transcriptomics,and the associated bioinformatics methods,and summarizes how their application has promoted our understanding of the emergence,composition,progression,and therapy responsiveness of,and intercellular signaling within,HNSCC. 展开更多
关键词 head and neck squamous cell carcinoma Tumor microenvironment IMMUNOTHERAPY Gene expression OMICS
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语域理论视角下的小学英语听说课情境设计——以PEP《英语》中的Let’s talk板块为例
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作者 张韦华 《教学月刊(小学版)(综合)》 2024年第4期33-37,共5页
针对教师在听说课的口语情境设计、语篇分析和课堂实践方面存在的问题,可以从语域理论进行思考。语域指的是与某一情境组成的语场、语旨、语式有关的语义集合。其中,语场、语旨、语式分别指伴随语言进行的社会活动、涉及的任务角色以及... 针对教师在听说课的口语情境设计、语篇分析和课堂实践方面存在的问题,可以从语域理论进行思考。语域指的是与某一情境组成的语场、语旨、语式有关的语义集合。其中,语场、语旨、语式分别指伴随语言进行的社会活动、涉及的任务角色以及语言所采用的符号或修辞手段。PEP《英语》中的Let’s talk板块是典型的听说课。教学时,教师可以关注观察与分析、归纳与判断、迁移与创新三个方面,通过“聚焦语场,挖掘语义;关注语式,重视人文;立意语旨,综合创新”等方式,使听说课教学更具人文情怀,使学生学会学习,实现实践创新,提升思维能力。 展开更多
关键词 语域理论 听说课 情境 Let’s talk
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Exploration of the efficacy and mechanism of treating head wind disease with the combination change of ginger volatile oil and gingerol by using content-weighted network pharmacology technology
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作者 Wei-Xiang Wang Fei Yan +5 位作者 Fei Luan Ya-Jun Shi Xiao-Fei Zhang Dong-Yan Guo Bing-Tao Zhai Jun-Bo Zou 《TMR Modern Herbal Medicine》 CAS 2024年第1期43-56,共14页
Background:Exploring the efficacy,potential components,and mechanism of the combination of ginger essential oil and gingerols in the treatment of head wind disease based on network pharmacology technology with content... Background:Exploring the efficacy,potential components,and mechanism of the combination of ginger essential oil and gingerols in the treatment of head wind disease based on network pharmacology technology with content weight.Methods:The experimental groups were divided into:0:10,1:4,1:2,1:1,2:1,4:1,10:0.The relative content(Ri)of the chemical constituents of ginger's volatile oil was determined using gas chromatography-mass spectrometry(GC-MS).Additionally,the physicochemical and biological property parameters(LogP,MDCK,PPB,MW)of the components were considered.To assess the quantitative effect of the components,a grading score was performed,and the quantitative effect index(Ki)was calculated.Subsequently,the target effect index(Ti)was calculated by combining the component-target matching score(Fit score).Using these calculations,the target effect score A was determined under the influence of multiple components targeting different targets.Key targets with A≥1000 were identified.To predict the targets related to head wind disease,the Comparative Toxicogenomics Database(https://ctdbase.org/),Gene Cards(https://www.genecards.org/),and Disgenet database(https://www.disgenet.org/)were utilized.The key targets,obtained from different proportions of ginger's volatile oil and gingerol,were intersected with the predicted targets.This facilitated network pharmacological analysis and verification of the efficacy.Results:The content of volatile oil in ginger demonstrated an impact on key targets associated with the volatile oil group.Each specific combination of volatile oil consistently activated distinct pathways,with variations stemming from changes in content.Experimental testing revealed that different combinations of ginger's volatile oil and gingerol effectively alleviated migraine symptoms in rats.Conclusion:Through the application of content-weighted network pharmacology technology and pharmacodynamic verification,it was determined that altering the ratio between ginger's volatile oil and gingerol leads to variations in potential targets and pathways,consequently impacting its efficacy. 展开更多
关键词 network pharmacology volatile oil of ginger weight of content head wind disease
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论英语书面表达与Free talk的有机融合
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作者 张广辉 《河南教育(基教版)(上)》 2024年第5期85-85,共1页
在英语学习中,Free talk是说的能力,书面表达是写的能力,二者互相联系又相互促进,要有机融合,才能促进英语水平的有效提高。一、初中英语书面表达现状。在初中英语质量检测中,学生词汇贫乏、句型单一、结构松散、逻辑混乱的问题普遍存... 在英语学习中,Free talk是说的能力,书面表达是写的能力,二者互相联系又相互促进,要有机融合,才能促进英语水平的有效提高。一、初中英语书面表达现状。在初中英语质量检测中,学生词汇贫乏、句型单一、结构松散、逻辑混乱的问题普遍存在。第一,受母语的影响导致汉语式英语,类似“I by bike to school every day”的表达司空见惯。 展开更多
关键词 英语书面表达 初中英语 词汇贫乏 有机融合 汉语式英语 talk 质量检测 逻辑混乱
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Multi-Head Attention Spatial-Temporal Graph Neural Networks for Traffic Forecasting
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作者 Xiuwei Hu Enlong Yu Xiaoyu Zhao 《Journal of Computer and Communications》 2024年第3期52-67,共16页
Accurate traffic prediction is crucial for an intelligent traffic system (ITS). However, the excessive non-linearity and complexity of the spatial-temporal correlation in traffic flow severely limit the prediction acc... Accurate traffic prediction is crucial for an intelligent traffic system (ITS). However, the excessive non-linearity and complexity of the spatial-temporal correlation in traffic flow severely limit the prediction accuracy of most existing models, which simply stack temporal and spatial modules and fail to capture spatial-temporal features effectively. To improve the prediction accuracy, a multi-head attention spatial-temporal graph neural network (MSTNet) is proposed in this paper. First, the traffic data is decomposed into unique time spans that conform to positive rules, and valuable traffic node attributes are mined through an adaptive graph structure. Second, time and spatial features are captured using a multi-head attention spatial-temporal module. Finally, a multi-step prediction module is used to achieve future traffic condition prediction. Numerical experiments were conducted on an open-source dataset, and the results demonstrate that MSTNet performs well in spatial-temporal feature extraction and achieves more positive forecasting results than the baseline methods. 展开更多
关键词 Traffic Prediction Intelligent Traffic System Multi-head Attention Graph Neural Networks
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巧用Self-talking和课堂设计提高英语口头表达能力
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作者 于薇 《黑龙江教育学院学报》 2005年第2期112-113,共2页
大学英语教学大纲阐明大学英语教学的重点是有效提高学生的实际交际能力。Self—talking对于学生自主学习能力的培养和英语交际能力的提高有着不可忽略的作用。外语学习归根结底是学生自身的学习,课堂是学生语言实践的重要场所。课堂教... 大学英语教学大纲阐明大学英语教学的重点是有效提高学生的实际交际能力。Self—talking对于学生自主学习能力的培养和英语交际能力的提高有着不可忽略的作用。外语学习归根结底是学生自身的学习,课堂是学生语言实践的重要场所。课堂教学不仅要扩大学生的语言知识,加强和提高学生的语言运用能力,还要帮助学生养成良好的自主学习习惯,尤其是Self-talking的自我对话意识和英语表达能力的训练,是对课堂英语口语训练的有益补充。 展开更多
关键词 交际能力 自主学习 自我对话
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Talking about Weather
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作者 崔荣斌 《疯狂英语(初中天地)》 2002年第32期17-17,共1页
英语中,谈论天气的交际用语很多。如:1.Beautiful day,isn't it?天气真好,不是吗?这是一个省略句,完整的句子是:It's a beautiful day,isn't it?在口语中,谈论天气时还有类似的省略:如:
关键词 talking about Weather
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Compacted graphite iron-A material solution for modern diesel engine cylinder blocks and heads 被引量:12
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作者 Steve Dawson SinterCast Sweden 《China Foundry》 SCIE CAS 2009年第3期241-246,共6页
The demands for improved fuel economy,performance and emissions continue to pose challenges for engine designers and the materials they choose. This is particularly true for modern diesel engines,where the primary pat... The demands for improved fuel economy,performance and emissions continue to pose challenges for engine designers and the materials they choose. This is particularly true for modern diesel engines,where the primary path to achieving improved engine performance and emissions is to increase the Peak Firing Pressure in the combustion chamber. The resulting increase in thermal and mechanical loading has required a change from conventional grey cast iron to Compacted Graphite Iron (CGI) in order to satisfy durability requirements without increasing the size or the weight of the engines. With at least 75% higher tensile strength,45% higher stiffness and approximately double the fatigue strength of conventional grey cast iron,CGI satisfies durability requirements and also provides the dimensional stability required to meet emissions legislation throughout the life of the engine. Currently,there are no CGI diesel engines running on the roads in North America. This is set to change considerably as new commercial vehicle and pick-up SUV diesel engines are launched with CGI cylinder blocks in 2008 and 2009. These initial programs will provide over 2 million CGI diesel engines when ramped to mature volume,potentially accounting for 10%-15% of the North American passenger vehicle fleet within the next four years. 展开更多
关键词 COMPACTED GRAPHITE iron modem DIESEL engine performance emission cylinder BLOCKS and heads
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Vessel density in OCT angiography permits differentiation between normal and glaucomatous optic nerve heads 被引量:9
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作者 Claudia Lommatzsch Kai Rothaus +2 位作者 Joerg Michael Koch Carsten Heinz Swaantje Grisanti 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第5期835-843,共9页
AIM:To evaluate whether optical coherence tomography angiography(OCTA) can detect altered vessel density(VD) at the optic nerve head(ONH) in glaucoma patients.Special attention is paid to the accuracy of the OCTA tech... AIM:To evaluate whether optical coherence tomography angiography(OCTA) can detect altered vessel density(VD) at the optic nerve head(ONH) in glaucoma patients.Special attention is paid to the accuracy of the OCTA technique for distinguishing healthy from glaucomatous eyes.METHODS:A total of 171 eyes were examined by the OCTA system Angio Vue^(TM)(Optovue):97 eyes diagnosed with glaucoma and 74 healthy control eyes.The papillary and peripapillary VD was measured.Furthermore,the VD was correlated with different structural and functional measurements.In order to test the accuracy of differentiation between eyes with and without glaucoma,we calculated the receiver operating characteristic curve(ROC) and the area under the curve(AUC).RESULTS:The papillary and peripapillary VD in glaucomatous eyes was significantly lower than in healthy eyes(P<0.05).The VD of the nasal peripapillary sector was significantly lower than in the other sectors.The further the disease had progressed [measured by determining the thickness of the ganglion cell complex(GCC) and the retinal nerve fiber layer(RNFL)] the greater the VD reduction.The AUC discriminated well between glaucomatous and normal eyes(consensus classifier 94.2%).CONCLUSION:OCTA allows non-invasive quantification of the peripapillary and papillary VD,which is significantly reduced in glaucomatous eyes and accurately distinguishes between healthy and diseased eyes.OCTA expands the spectrum of procedures for detecting and monitoring glaucoma. 展开更多
关键词 optical coherence tomography angiography glaucoma optic nerve head blood flow
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Quantitative Survivability Analysis Using Probability Model Checking: A Study of Cluster-Based Vehicle Networks with Dual Cluster Heads 被引量:2
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作者 Li Jin Guoan Zhang +2 位作者 Jue Wang Hao Zhu Wei Duan 《China Communications》 SCIE CSCD 2020年第2期206-219,共14页
As an important part of future 5G wireless networks,a vehicular network demands safety,reliability and connectivity.In this context,networking survivability is usually considered an important metric to evaluate networ... As an important part of future 5G wireless networks,a vehicular network demands safety,reliability and connectivity.In this context,networking survivability is usually considered an important metric to evaluate network performance.In this paper,we propose a survivability model for vehicle communication networking based on dual cluster heads,wherein a backup cluster head(CH)will be activated if the primary CH fails,thereby effectively enhancing the network lifetime.Additionally,we introduce a software rejuvenation strategy for the prime CH to further improve the survivability of the entire network.Using the Probabilistic Symbolic Model Checker(PRISM),we verify and discuss the proposed survivability model via numerical simulations.The results show that network survivability can be effectively improved by introducing an additional CH and further enhanced by adopting the software rejuvenation technique. 展开更多
关键词 cluster head 5G software recovery SURVIVABILITY vehicle networks
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