semantics

语义
  • 文章类型: Journal Article
    患者门户信息通常涉及特定的临床现象(例如,正在接受乳腺癌治疗的患者)和,因此,越来越受到生物医学研究的重视。这些消息需要自然语言处理,而单词嵌入模型,如word2vec,有可能从文本中提取有意义的信号,它们不适用于患者门户消息。这是因为嵌入模型通常需要数百万个训练样本来充分表示语义,而与特定临床现象相关的患者入口信息的量通常相对较小。我们介绍了一种对word2vec模型的新颖改编,PK-word2vec(其中PK代表先验知识),用于小规模的消息。PK-word2vec包含了医学词汇最相似的术语(包括问题,治疗,和测试)以及来自两个预训练嵌入模型的非医学单词作为先验知识,以改善训练过程。我们将PK-word2vec应用于2004年12月至2017年11月在范德比尔特大学医学中心电子健康记录系统中发送的患者门户消息的案例研究。我们通过一组1000个任务来评估模型,每个单词的相关性与一组由PK-word2vec生成的五个最相似的单词和一组由标准word2vec模型生成的五个最相似的单词进行比较。我们招募了200名亚马逊土耳其机械(AMT)工人和7名医学生来执行任务。该数据集由1389个患者记录组成,包括137,554条消息和10,683个独特单词。已有7981个非医学单词和1116个医学单词的先验知识。在90%以上的任务中,两位审稿人均表示,PK-word2vec比标准word2vec生成的相似词更多(p=0.01).对于两组审阅者之间的任务选择的所有比较,AMT工作者与医学生的评估差异都可以忽略不计(配对t检验下p=0.774)。PK-word2vec可以从小型消息语料库中有效地学习单词表示,标志着在处理患者门户消息方面的显著进步。
    Patient portal messages often relate to specific clinical phenomena (e.g., patients undergoing treatment for breast cancer) and, as a result, have received increasing attention in biomedical research. These messages require natural language processing and, while word embedding models, such as word2vec, have the potential to extract meaningful signals from text, they are not readily applicable to patient portal messages. This is because embedding models typically require millions of training samples to sufficiently represent semantics, while the volume of patient portal messages associated with a particular clinical phenomenon is often relatively small. We introduce a novel adaptation of the word2vec model, PK-word2vec (where PK stands for prior knowledge), for small-scale messages. PK-word2vec incorporates the most similar terms for medical words (including problems, treatments, and tests) and non-medical words from two pre-trained embedding models as prior knowledge to improve the training process. We applied PK-word2vec in a case study of patient portal messages in the Vanderbilt University Medical Center electric health record system sent by patients diagnosed with breast cancer from December 2004 to November 2017. We evaluated the model through a set of 1000 tasks, each of which compared the relevance of a given word to a group of the five most similar words generated by PK-word2vec and a group of the five most similar words generated by the standard word2vec model. We recruited 200 Amazon Mechanical Turk (AMT) workers and 7 medical students to perform the tasks. The dataset was composed of 1389 patient records and included 137,554 messages with 10,683 unique words. Prior knowledge was available for 7981 non-medical and 1116 medical words. In over 90% of the tasks, both reviewers indicated PK-word2vec generated more similar words than standard word2vec (p = 0.01).The difference in the evaluation by AMT workers versus medical students was negligible for all comparisons of tasks\' choices between the two groups of reviewers ( p = 0.774 under a paired t-test). PK-word2vec can effectively learn word representations from a small message corpus, marking a significant advancement in processing patient portal messages.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    语义记忆表示通常在老化时保持得很好,而语义控制被认为受到的影响更大。为了解释这种现象,这项研究测试了与补偿相关的神经电路利用假说(CRUNCH)的预测,关注老龄化中的任务需求,作为一个可能的框架。CRUNCH效应将通过语义控制网络区域中神经激活的补偿性增加而在语义任务中表现出来,但仅达到任务需求的特定阈值。这项研究比较了在fMRI扫描仪中执行的基于三元组的语义判断任务中39名年轻(20-35岁)和39名年龄较大的参与者(60-75岁),同时通过语义距离操纵任务需求水平(低与高)。根据CRUNCH的预测,在神经功能激活和行为表现(准确性和反应时间)的差异预计在年轻和老年参与者在低和高需求条件下,这应该表现在语义控制感兴趣区域(ROI)中。我们年长的参与者有完整的行为表现,如文献中提出的语义记忆任务(保持准确性和较慢的响应时间(RT))。与年轻组相比,年龄不变的行为表现对于测试CRUNCH预测是必要的。老年人的特征还在于高认知储备,正如我们的神经心理学测试所显示的。我们的行为结果证实,我们的任务成功地操纵了任务需求:错误率,RTs和感知难度随着两个年龄组任务需求的增加而增加。我们没有发现年龄组和任务需求之间的相互作用,或在RTs或准确性的低需求和高需求条件之间的激活有统计学意义的差异。至于大脑激活,我们没有通过任务需求交互找到预期的年龄组,或任务需求的显著主效应。总的来说,我们的结果与语义网络和语义控制网络中的一些神经激活相一致,主要在额孢子顶区域。ROI分析表明,任务需求在左右额下回有显著影响(但没有相互作用),左侧颞中后回,颞下后回和前额回。总的来说,我们的测试没有证实CRUNCH的预测。
    Semantic memory representations are generally well maintained in aging, whereas semantic control is thought to be more affected. To explain this phenomenon, this study tested the predictions of the Compensation-Related Utilization of Neural Circuits Hypothesis (CRUNCH), focusing on task demands in aging as a possible framework. The CRUNCH effect would manifest itself in semantic tasks through a compensatory increase in neural activation in semantic control network regions but only up to a certain threshold of task demands. This study compares 39 younger (20-35 years old) with 39 older participants (60-75 years old) in a triad-based semantic judgment task performed in an fMRI scanner while manipulating task demand levels (low versus high) through semantic distance. In line with the CRUNCH predictions, differences in neurofunctional activation and behavioral performance (accuracy and response times) were expected in younger versus older participants in the low- versus high-demand conditions, which should be manifested in semantic control Regions of Interest (ROIs). Our older participants had intact behavioral performance, as proposed in the literature for semantic memory tasks (maintained accuracy and slower response times (RTs)). Age-invariant behavioral performance in the older group compared to the younger one is necessary to test the CRUNCH predictions. The older adults were also characterized by high cognitive reserve, as our neuropsychological tests showed. Our behavioral results confirmed that our task successfully manipulated task demands: error rates, RTs and perceived difficulty increased with increasing task demands in both age groups. We did not find an interaction between age group and task demand, or a statistically significant difference in activation between the low- and high-demand conditions for either RTs or accuracy. As for brain activation, we did not find the expected age group by task demand interaction, or a significant main effect of task demand. Overall, our results are compatible with some neural activation in the semantic network and the semantic control network, largely in frontotemporoparietal regions. ROI analyses demonstrated significant effects (but no interactions) of task demand in the left and right inferior frontal gyrus, the left posterior middle temporal gyrus, the posterior inferior temporal gyrus and the prefrontal gyrus. Overall, our test did not confirm the CRUNCH predictions.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    成像的进步,计算机视觉,自动化彻底改变了各个领域,包括基于田间的高通量植物表型鉴定(FHTPP)。这种整合允许快速准确地测量植物性状。深度卷积神经网络(DCNN)已经成为FHTPP中的一个强大工具,特别是在作物分割中-从背景中识别作物-对于性状分析至关重要。然而,DCNN的有效性通常取决于大型,标记的数据集,由于标签的高成本,这带来了挑战。在这项研究中,引入了一种带套袋的深度学习方法,以使用高分辨率RGB图像增强作物分割,在玉米地块的NU-Spidercam数据集上测试。该方法在预测精度和速度上优于传统的机器学习和深度学习模型。值得注意的是,它比阈值方法实现了高达40%的交叉联合(IoU),比传统机器学习提高了11%,具有明显更快的预测时间和可管理的训练持续时间。至关重要的是,它表明,即使是小的标记数据集也可以在语义分割中产生很高的准确性。这种方法不仅对FHTPP有效,而且还暗示了在遥感中更广泛应用的潜力,为语义分割挑战提供可扩展的解决方案。本文附有公开可用的源代码。
    Advancements in imaging, computer vision, and automation have revolutionized various fields, including field-based high-throughput plant phenotyping (FHTPP). This integration allows for the rapid and accurate measurement of plant traits. Deep Convolutional Neural Networks (DCNNs) have emerged as a powerful tool in FHTPP, particularly in crop segmentation-identifying crops from the background-crucial for trait analysis. However, the effectiveness of DCNNs often hinges on the availability of large, labeled datasets, which poses a challenge due to the high cost of labeling. In this study, a deep learning with bagging approach is introduced to enhance crop segmentation using high-resolution RGB images, tested on the NU-Spidercam dataset from maize plots. The proposed method outperforms traditional machine learning and deep learning models in prediction accuracy and speed. Remarkably, it achieves up to 40% higher Intersection-over-Union (IoU) than the threshold method and 11% over conventional machine learning, with significantly faster prediction times and manageable training duration. Crucially, it demonstrates that even small labeled datasets can yield high accuracy in semantic segmentation. This approach not only proves effective for FHTPP but also suggests potential for broader application in remote sensing, offering a scalable solution to semantic segmentation challenges. This paper is accompanied by publicly available source code.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    我们报告了首次使用ERP措施来识别数字或印刷阅读时的文本参与度差异。语义编码的深度是阅读理解的关键,我们预测,对说明性文本的更深入阅读将促进与随后呈现的相关单词的更强关联,导致N400对无关探针词的响应增强,以及N400对相关和中度相关词的分级衰减。相比之下,浅阅读会产生探针词和文本段落之间较弱的联系,导致N400对中等相关和不相关单词的响应增强,对相关单词的反应减弱。行为研究表明,来自纸张的文本比来自屏幕的文本的语义编码更深。因此,我们预测,N400将索引更深入地阅读印刷文本段落,对数字呈现的文本的阅读更浅。中学生(n=59)以数字和印刷格式阅读段落,并记录高密度脑电图,而参与者在每次段落后完成单单词语义判断任务。在数字文本演示之后,N400对中等相关单词的反应模式表明阅读浅,跟踪与文本无关的单词的响应。在打印阅读之后,N400对中度相关单词的响应,而不是对相关单词的响应,解释为更深入阅读的索引。这些发现提供了大脑对印刷和数字媒体中文本反应差异的证据。包括比数字文本更深的印刷语义编码。
    We report the first use of ERP measures to identify text engagement differences when reading digitally or in print. Depth of semantic encoding is key for reading comprehension, and we predicted that deeper reading of expository texts would facilitate stronger associations with subsequently-presented related words, resulting in enhanced N400 responses to unrelated probe words and a graded attenuation of the N400 to related and moderately related words. In contrast, shallow reading would produce weaker associations between probe words and text passages, resulting in enhanced N400 responses to both moderately related and unrelated words, and an attenuated response to related words. Behavioral research has shown deeper semantic encoding of text from paper than from a screen. Hence, we predicted that the N400 would index deeper reading of text passages that were presented in print, and shallower reading of texts presented digitally. Middle-school students (n = 59) read passages in digital and print formats and high-density EEG was recorded while participants completed single-word semantic judgment tasks after each passage. Following digital text presentation, the N400 response pattern to moderately-related words indicated shallow reading, tracking with responses to words that were unrelated to the text. Following print reading, the N400 responses to moderately-related words patterned instead with responses to related words, interpreted as an index of deeper reading. These findings provide evidence of differences in brain responses to texts presented in print and digital media, including deeper semantic encoding for print than digital texts.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    任何书写系统中的拼写都受基本原则的支配。我们研究了两种类型的伪同音词的处理,这些词的拼写基于不同的原则-根据传统的写作原则,需要记住他们的拼写,根据形态学原理,允许从具有相同语素(根)的另一个单词确定其拼写,以检查拼字法语音冲突的发生对拼写原则的依赖性。在无声阅读期间,记录了22名志愿者的事件相关电位。基于形态学原理的伪同音增加了N400的振幅,强调语义和形态加工的重要性。P600分量显示出基于传统原理区分单词和伪同音的显著效果,主要表明参与记忆和重新分析过程。源重建表明,两个伪同音都激活了左额下回。然而,基于传统原理的伪同音额外激活左右中央后回,表明其他领域参与了分化过程。基于形态学原理的刺激的早期差异表明可以使用较小的单位(语素),而基于传统原理的刺激需要整个文字处理。我们的发现强调了拼写原则在正字法处理中的重要作用。
    Spelling in any writing system is governed by fundamental principles. We examined the processing of two types of pseudohomophones constructed from words whose spellings are based on different principles - on the traditional principle of writing, requiring memorization of their spelling, and on the morphological principle, allowing the determination of their spelling from another word with the same morpheme (root) to examine the dependence of the occurrence of orthography-phonology conflict on spelling principles. Event-related potentials were recorded from 22 volunteers during silent reading. Pseudohomophones based on the morphological principle increased the N400 amplitude, emphasizing semantic and morphological processing importance. The P600 component showed significant effects for differentiating words and pseudohomophones based on the traditional principle, predominantly indicating the involvement of memory and reanalysis processes. Source reconstruction demonstrates that both pseudohomophones activate the left inferior frontal gyrus. However, pseudohomophones based on the traditional principle additionally activate the right and left postcentral gyrus, indicating the involvement of additional areas in the differentiation process. The earlier differences for stimuli based on the morphological principle indicate access to smaller units (morphemes), whereas stimuli based on the traditional principle require whole word processing. Our findings underscore the significant role of spelling principles in orthographic processing.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    禁忌词的使用代表了最常见和可以说是普遍的语言行为之一,履行广泛的心理和社会功能。然而,在科学文献中,禁忌语言特征不佳,以及它是如何在不同的语言和人群中实现的,在很大程度上仍未被探索。这里我们提供了一个禁忌词的数据库,从不同的语言社区收集(研究1,N=1046),以及他们以说话者为中心的语义表征(研究2,六个评级维度中的每一个N=455),覆盖所有五个永久居住大陆的13种语言和17个国家。我们的研究结果表明,在所有语言中,禁忌词的主要特点是低效价和高唤醒,很低的写入频率。然而,大量的跨国差异的词汇禁忌和攻击性证明了社区特有的社会文化知识在禁忌语言研究中的重要性。
    The use of taboo words represents one of the most common and arguably universal linguistic behaviors, fulfilling a wide range of psychological and social functions. However, in the scientific literature, taboo language is poorly characterized, and how it is realized in different languages and populations remains largely unexplored. Here we provide a database of taboo words, collected from different linguistic communities (Study 1, N = 1046), along with their speaker-centered semantic characterization (Study 2, N = 455 for each of six rating dimensions), covering 13 languages and 17 countries from all five permanently inhabited continents. Our results show that, in all languages, taboo words are mainly characterized by extremely low valence and high arousal, and very low written frequency. However, a significant amount of cross-country variability in words\' tabooness and offensiveness proves the importance of community-specific sociocultural knowledge in the study of taboo language.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    适当的针头操作以避免脆弱血管的突然变形是微血管吻合成功的关键决定因素。然而,尚未有研究使用手术录像评估手术对象的面积变化.因此,本研究旨在开发一种基于深度学习的语义分割算法,以评估微血管吻合过程中血管的面积变化,以客观地评估对组织的尊重。“语义分割算法是基于ResNet-50网络使用具有人造血管的微血管端到端吻合训练视频进行训练的。使用创建的模型,在单个缝合完成任务期间的视频参数,包括血管面积变异系数(CV-VA),单位时间内血管面积的相对变化(ΔVA),和组织变形误差(TDE)的数量,由ΔVA阈值定义,在专家和新手外科医生之间进行了比较。对于自动分割模型,获得了较高的验证准确性(99.1%)和联合交集(0.93)。在单针任务中,专家外科医生显示较低的CV-VA值(p<0.05)和ΔVA值(p<0.05)。此外,专家承诺的TDE明显少于新手(p<0.05),并在较短的时间内完成任务(p<0.01)。接收器工作曲线分析表明,每个视频参数和任务完成时间具有相对较强的辨别能力,而任务完成时间和视频参数的结合使用显示了专家和新手之间的完全区分能力。总之,使用基于深度学习的语义分割算法评估微血管吻合过程中血管面积的变化被提出作为评估显微外科手术性能的新概念。这将在未来的计算机辅助设备中有用,以增强手术教育和患者安全。
    Appropriate needle manipulation to avoid abrupt deformation of fragile vessels is a critical determinant of the success of microvascular anastomosis. However, no study has yet evaluated the area changes in surgical objects using surgical videos. The present study therefore aimed to develop a deep learning-based semantic segmentation algorithm to assess the area change of vessels during microvascular anastomosis for objective surgical skill assessment with regard to the \"respect for tissue.\" The semantic segmentation algorithm was trained based on a ResNet-50 network using microvascular end-to-side anastomosis training videos with artificial blood vessels. Using the created model, video parameters during a single stitch completion task, including the coefficient of variation of vessel area (CV-VA), relative change in vessel area per unit time (ΔVA), and the number of tissue deformation errors (TDE), as defined by a ΔVA threshold, were compared between expert and novice surgeons. A high validation accuracy (99.1%) and Intersection over Union (0.93) were obtained for the auto-segmentation model. During the single-stitch task, the expert surgeons displayed lower values of CV-VA (p < 0.05) and ΔVA (p < 0.05). Additionally, experts committed significantly fewer TDEs than novices (p < 0.05), and completed the task in a shorter time (p < 0.01). Receiver operating curve analyses indicated relatively strong discriminative capabilities for each video parameter and task completion time, while the combined use of the task completion time and video parameters demonstrated complete discriminative power between experts and novices. In conclusion, the assessment of changes in the vessel area during microvascular anastomosis using a deep learning-based semantic segmentation algorithm is presented as a novel concept for evaluating microsurgical performance. This will be useful in future computer-aided devices to enhance surgical education and patient safety.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    背景:食管癌治疗的最新进展,包括探索放化疗后主动监测的研究,导致需要关于不同多式联运治疗方案的明确术语和定义。
    目的:本研究的目的是就多模式食管癌治疗的定义和语义达成全球共识。
    方法:总共,72名在多模式食管癌治疗领域工作的专家被邀请参加这项德尔菲研究。该研究包括通过电子邮件发送的三项Delphi调查和一次在线会议。Delphi调查的输入包括从系统的文献检索中获得的术语。要求参与者回答悬而未决的问题,并指出他们是否同意或不同意不同的陈述。当受访者达成≥75%的共识时,就达成了共识。
    结果:72位受邀专家中有49位(68.1%)参加了首次在线德尔菲调查,45(62.5%)在第二次调查中,在线会议中45人中有21人(46.7%),在最后一次调查中,45人中有39人(86.7%)。31个项目中的27个(87%)达成了有或没有手术的新辅助和确定性放化疗共识。使用确定性放化疗治疗后的随访未达成共识。
    结论:关于多模式食管癌治疗的术语和定义的大多数陈述达成共识。实施统一标准有利于研究比较,促进国际研究合作。
    BACKGROUND: Recent developments in esophageal cancer treatment, including studies exploring active surveillance following chemoradiotherapy, have led to a need for clear terminology and definitions regarding different multimodal treatment options.
    OBJECTIVE: The aim of this study was to reach worldwide consensus on the definitions and semantics of multimodal esophageal cancer treatment.
    METHODS: In total, 72 experts working in the field of multimodal esophageal cancer treatment were invited to participate in this Delphi study. The study comprised three Delphi surveys sent out by email and one online meeting. Input for the Delphi survey consisted of terminology obtained from a systematic literature search. Participants were asked to respond to open questions and to indicate whether they agreed or disagreed with different statements. Consensus was reached when there was ≥75% agreement among respondents.
    RESULTS: Forty-nine of 72 invited experts (68.1%) participated in the first online Delphi survey, 45 (62.5%) in the second survey, 21 (46.7%) of 45 in the online meeting, and 39 (86.7%) of 45 in the final survey. Consensus on neoadjuvant and definitive chemoradiotherapy with or without surgery was reached for 27 of 31 items (87%). No consensus was reached on follow-up after treatment with definitive chemoradiotherapy.
    CONCLUSIONS: Consensus was reached on most statements regarding terminology and definitions of multimodal esophageal cancer treatment. Implementing uniform criteria facilitates comparison of studies and promotes international research collaborations.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    单词,与图像不同,是象征性的表示。一个词的含义和它产生的视觉图像中固有的联想细节,与单词的处理和表示方式密不可分。众所周知,海马体与记忆的组成部分相关联以形成持久的表示,在这里,我们表明海马体对抽象文字处理特别敏感。在识别过程中使用功能磁共振成像,我们发现,无论记忆结果如何,词汇抽象性的增加都会增加海马的激活.有趣的是,无论单词内容如何,单词回忆都会产生海马激活,虽然海马旁皮层对单词表示的具体性很敏感,不管记忆结果如何。我们认为海马体在非语境化抽象单词含义的表示中发挥了关键作用,因为它的信息绑定能力允许检索语义和视觉关联,当捆绑在一起时,生成由单词符号表示的抽象概念。这些见解对单词表示的研究有意义,记忆,和海马功能,也许揭示了人类大脑如何适应编码和表示抽象概念。
    Words, unlike images, are symbolic representations. The associative details inherent within a word\'s meaning and the visual imagery it generates, are inextricably connected to the way words are processed and represented. It is well recognised that the hippocampus associatively binds components of a memory to form a lasting representation, and here we show that the hippocampus is especially sensitive to abstract word processing. Using fMRI during recognition, we found that the increased abstractness of words produced increased hippocampal activation regardless of memory outcome. Interestingly, word recollection produced hippocampal activation regardless of word content, while the parahippocampal cortex was sensitive to concreteness of word representations, regardless of memory outcome. We reason that the hippocampus has assumed a critical role in the representation of uncontextualized abstract word meaning, as its information-binding ability allows the retrieval of the semantic and visual associates that, when bound together, generate the abstract concept represented by word symbols. These insights have implications for research on word representation, memory, and hippocampal function, perhaps shedding light on how the human brain has adapted to encode and represent abstract concepts.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    本研究采用事件相关电位(ERP)技术来研究隐喻背景下汉语动作动词的处理是否存在具体性效应。将动作隐喻激活的N400的平均振幅与文字动词和抽象动词激活的平均振幅进行比较。研究结果表明,与Abs动词相比,Met动词在200-500ms的时间窗口在额叶大脑区域引起的N400反应明显更大,而Met动词在300-500ms时间窗口时与Lit动词相比,在后脑区域引起的N400幅度明显更大。这些结果可以解释为表明对Met动词的理解基于具体的动作语义。
    The present research adopts ERP (Event-Related Potentials) technology to investigate whether there exists a concreteness effect in the processing of Chinese action verbs within metaphorical context. The mean amplitudes of N400 activated by action metaphors were compared with those activated by literal verbs and abstract verbs. The findings indicated that the Met verbs evoked a significantly larger N400 response at frontal brain region compared to the Abs verbs at a time window 200-500 ms, while the Met verbs elicited a notably greater N400 amplitude specifically at the posterior brain region in comparison to the Lit verbs at 300-500 ms time window. These results may be interpreted as indicating that the comprehension of the Met verbs is based on the concrete action semantics.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

公众号