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Role of optical spectroscopy using endogenous contrasts in clinical cancer diagnosis 被引量:1
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作者 Quan Liu 《World Journal of Clinical Oncology》 CAS 2011年第1期50-63,共14页
Optical spectroscopy has been intensively studied for cancer management in the past two decades.This review paper first introduces the background of optical spectroscopy for cancer management,which includes the advant... Optical spectroscopy has been intensively studied for cancer management in the past two decades.This review paper first introduces the background of optical spectroscopy for cancer management,which includes the advantages of optical techniques compared to other established techniques,the principle of optical spectroscopy and the typical setup of instrumentation.Then the recent progress in optical spectroscopy for cancer diagnosis in the following organs is reviewed:the brain,breast,cervix,lung,stomach,colon,prostate and the skin.Reviewed papers were selected from the PubMed database with keywords combining the terms of individual optical spectroscopy techniques and cancers.The primary focus is on the in vivo applications of optical spectroscopy in clinical studies.Ex vivo studies are also included for some organs to highlight special applications or when there are few in vivo results in the literature.Practical considerations of applying optical spectroscopy in clinical settings such as the speed,cost,complexity of operation,accuracy and clinical value are discussed.A few commercially available clinical instruments that are based on optical spectroscopy techniques are presented.Finally several technical challenges and standard issues are discussed and firm conclusions are made. 展开更多
关键词 Cancer diagnosis CLINICAL ONCOLOGY ENDOGENOUS contrasts OPTICAL SPECTROSCOPY
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The Contrasts of English Sentences and Chinese Sentences and Translation Skills
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作者 郭丁菊 张晶 《英语广场(学术研究)》 2013年第3期21-22,共2页
Since the opening-up policy was carried out in 1979, every facility of social modernized construction has developed at high speed; meanwhile, the need of English is increased year by year. The occasion and scope of us... Since the opening-up policy was carried out in 1979, every facility of social modernized construction has developed at high speed; meanwhile, the need of English is increased year by year. The occasion and scope of using it are expanded with the communications among countries. Therefore, English has become the generally international language in our country; in particular, translation plays an important and irreplaceable part in English to convey information. This paper aims to introduce the contrasts of English sentences and Chinese sentences and discuss some skills of translating each other. Though it is not complete and authoritative, yet it may help some people to understand the differences between two languages and to grasp some practical skills. 展开更多
关键词 TRANSLATION contrasts Chinese sentences English sentences translation skills
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Interpretation of Contrasts Employed in The Virtues of Growing Older
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作者 李超慧 曲英杰 《海外英语》 2013年第18期177-178,186,共3页
People make comparison and contrasts everyday,though they may not be aware of it. Comparison and contrast are ma jor methods to develop a piece of exposition. This paper mainly interprets the effective use of contrast... People make comparison and contrasts everyday,though they may not be aware of it. Comparison and contrast are ma jor methods to develop a piece of exposition. This paper mainly interprets the effective use of contrasts in The Virtues of Growing Older and explores the language art of an exposition. 展开更多
关键词 EXPOSITION Contrast Integrated English PARALLELISM
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Contrasts in Eugene O'Neill's Beyond the Horizon
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作者 纪小军 《海外英语》 2010年第5X期203-204,共2页
In Beyond the Horizon,a three-act play,Eugene O'Neill successfully employs the techinique of contrast,namely,contrasts between different characters,between indoor and outdoor settings,and between seasons,which hel... In Beyond the Horizon,a three-act play,Eugene O'Neill successfully employs the techinique of contrast,namely,contrasts between different characters,between indoor and outdoor settings,and between seasons,which help to acquire rich symbolic meaning and intensify the tragic sense of the play. 展开更多
关键词 CONTRAST CHARACTERS SETTINGS SEASONS
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Perception of English Tense and Lax Vowel Contrasts in Chinese Learners of English
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作者 袁勤 《海外英语》 2016年第17期202-204,共3页
This paper aims at examining the perception of English tense and lax vowel contrasts by testing an identification task of CVC syllables with different manipulated durations in Chinese learners of English.This can prov... This paper aims at examining the perception of English tense and lax vowel contrasts by testing an identification task of CVC syllables with different manipulated durations in Chinese learners of English.This can provide some empirical evidence for English as a second language teachers in teaching second language pronunciation. 展开更多
关键词 PERCEPTION tense and lax vowel contrast duration
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Images,Contrasts and Repetitions in A Farewell to Arms
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作者 廖綵胜 《外国语言文学》 1988年第1期85-95,共11页
二十世纪美国文坛上有影响的作家欧内斯特·海明威的小说《别了,武器》,是一部关于爱情和战争的悲剧。小说描写在第一次世界大战中,美国青年弗列德里克·亨利和护士凯塞琳·巴克莱的爱情,以及在战争冷酷的现实中他们梦幻的... 二十世纪美国文坛上有影响的作家欧内斯特·海明威的小说《别了,武器》,是一部关于爱情和战争的悲剧。小说描写在第一次世界大战中,美国青年弗列德里克·亨利和护士凯塞琳·巴克莱的爱情,以及在战争冷酷的现实中他们梦幻的破灭。本文着重分析作者如何通过气候、地形等自然现象,以雨为主形象,运用对照、重复的手法,突出体现小说的主题:在冠冕堂皇词藻掩盖下,战争带来的是失意、毁灭和死亡。 展开更多
关键词 Images contrasts and Repetitions in A Farewell to Arms
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NUMERICAL SIMULATION EXPERIMENTS OF THE IMPACTS OF LOCAL LAND-SEA THERMODYNAMIC CONTRASTS ON THE SCS SUMMER MONSOON ONSET 被引量:2
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作者 任雪娟 钱永甫 《Journal of Tropical Meteorology》 SCIE 2003年第1期1-8,共8页
The important effects of local land-sea thermodynamic contrast between the South China Sea (SCS) and Indochina Peninsula on SCS summer monsoon onset are preliminarily studied by using two sets of SSTA tests and two id... The important effects of local land-sea thermodynamic contrast between the South China Sea (SCS) and Indochina Peninsula on SCS summer monsoon onset are preliminarily studied by using two sets of SSTA tests and two ideal tests in s-p regional climate model. The result shows that warm SST in the SCS in winter and spring is favorable for the formation of monsoon circulation throughout all levels of the atmosphere over the sea, which hastens the onset of SCS summer monsoon. The effects of cold SST are generally the opposite. The local land-sea contrast in the SCS is one of the possible reasons for SCS summer monsoon onset. Superposed upon large-scale land-sea thermodynamic differences, it facilitates the formation of out-breaking onset characteristics of SCS summer monsoon in the SCS area. 展开更多
关键词 local land-sea thermodynamic contrast SCS summer monsoon p-σregional climate model
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A Brief Review of Lexico-semantic Contrasts between English and Chinese
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作者 杨丽 《海外英语》 2014年第6X期252-253,共2页
Contrastive linguistics belongs to a branch of linguistics.It studies two or more languages synchronically.However,lexicology is the study of lexical items of a language.An English sentence or a Chinese sentence forme... Contrastive linguistics belongs to a branch of linguistics.It studies two or more languages synchronically.However,lexicology is the study of lexical items of a language.An English sentence or a Chinese sentence formed based on words and clauses.Because of differences in Cultures,the lexical meanings between English and Chinese differ in many aspects,such as motivation of words and sense relationships.This paper is a brief review that just likes a book report,mainly based on the book Contrastive Linguistics,of lexico-semantic contrasts between English and Chinese,illustrated with several examples in both English and Chinese. 展开更多
关键词 CONTRASTIVE analysis lexico-semantic CONTRAST cont
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Improvement of distension and mural visualization of bowel loops using neutral oral contrasts in abdominal computed tomography
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作者 Jahanbakhsh Hashemi Yasmin Davoudi +2 位作者 Mina Taghavi Masoud Pezeshki Rad Amien Mahajeri Moghadam 《World Journal of Radiology》 CAS 2014年第12期907-912,共6页
AIM: To assess and compare the image quality of 4% sorbitol and diluted iodine 2%(positive oral contrast agent) in abdomino-pelvic multi-detector computed tomography.METHODS: Two-hundred patients, referred to the Radi... AIM: To assess and compare the image quality of 4% sorbitol and diluted iodine 2%(positive oral contrast agent) in abdomino-pelvic multi-detector computed tomography.METHODS: Two-hundred patients, referred to the Radiology Department of a central educational hospital for multi-detector row abdominal-pelvic computed tomography, were randomly divided into two groups: the first group received 1500 m L of 4% sorbitol solution as a neutral contrast agent, while in the second group 1500 m L of meglumin solution as a positive contrast agent was administered in a one-way randomized prospective study. The results were independently reviewed by two radiologists. Luminal distension and mural thickness and mucosal enhancement were compared between the two groups. Statistical analysis of the results was performed by Statistical Package for the Social Sciences software version 16 and the Mann-Whitney test at a confidence level of 95%. RESULTS: Use of neutral oral contrast agent significantly improved visualization of the small bowel wall thickness and mural appearance in comparison with administration of positive contrast agent(P < 0.01). In patients who received sorbitol, the small bowel showed better distention compared with those who received iodine solution as a positive contrast agent(P < 0.05). CONCLUSION: The results of the study demonstrated that oral administration of sorbitol solution allows better luminal distention and visualization of mural features than iodine solution as a positive contrast agent. 展开更多
关键词 MULTIDETECTOR row computed tomography scan NEUTRAL CONTRAST AGENT Positive CONTRAST AGENT
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Velocity and density contrasts across the Moho interface of Guangdong province in south China constrained by receiver functions
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作者 Yin-Ping Qian Xu-Zhang Shen +2 位作者 Xin Zhang Wen-Jun Zheng Yue-Jun Wang 《Earthquake Science》 2020年第3期141-152,共12页
The P receiver function includes P-to-SV converted phases and multiple reverberations of the discontinuities in the crust and mantle.The time of these phases is related to the crustal thickness and vp/vs ratio,and the... The P receiver function includes P-to-SV converted phases and multiple reverberations of the discontinuities in the crust and mantle.The time of these phases is related to the crustal thickness and vp/vs ratio,and the amplitude of these phases is mainly controlled by the velocity and density contrast of interfaces.By using H-κstacking method,this work estimated the crustal thickness and vP/vS ratio beneath the stations in the Guangdong province of South China.The velocity and density contrast(δβ-δρ)scanning stacking algorithm of the receiver function is applied to constrain the velocity and density contrast of the Moho in Guangdong province.This work analyzed the results of the crustal thickness,vp/vS ratio,and the velocity and density contrasts of Moho.The results indicate that the velocity contrast is higher beneath Yangjiang area in western Guangdong province and Nanao area in eastern Guangdong,which has a strong correlation with the distribution of geothermal springs in local areas and the characteristics of high heat flow.The velocity contrast of Moho has also a good correlation with the vP/vS ratio and the crustal thickness,which indicates that there is a strong material composition contrasts of the Moho in the study area.Velocity and density contrasts of Moho in some local area(such as western Guangdong)are somewhat consistent with the seismic activities. 展开更多
关键词 Moho discontinuity velocity contrast density con—trast receiver function Guangdong province
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Using Contrasts in One-Way Analysis of Variance with Control Groups and an Application
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作者 Demet Canga Ceren Efe 《Journal of Agricultural Science and Technology(A)》 2017年第7期474-478,共5页
In this study, it was shown that, same comparisons can be made by using contrast coefficients instead of Dunnett's test in the experiments with control groups. It was also shown that, in situations with an ordinal sc... In this study, it was shown that, same comparisons can be made by using contrast coefficients instead of Dunnett's test in the experiments with control groups. It was also shown that, in situations with an ordinal scale and equal spacing quantitative grouping, a trend investigation could be done by contrast coefficients. For this purpose, a small part of the data from a TUBITAK project in the Soil Science Department, Agriculture Faculty, Kahramanmaras Sutcu Imam University, was used with permission. The soils were absorbed to natural zeolite in concentration of 0, 2.5, 5 and 10 mg/kg, and after two years, the available Zinc (Zn) amounts in the soil were analyzed. As a result, in both Dunnett's test and contrast methods, the Zn amounts in control and 2.5 mg/kg concentration groups were found similar (P 〉 0.01); but were different (P 〈 0.01) between control and 5 mg/kg concentration groups, and control and 10 mg/kg concentration groups. Furthermore, when orthogonal polynomial contrast coefficients were investigated, linear effects were found significant (P 〈 0.01) and cubic effects were obtained significant (P 〈 0.05), but quadratic effect was obtained insignificant (P 〉 0.05). 展开更多
关键词 Analysis of variance (ANOVA) comparisons Dunnett's test CONTRAST trend analysis.
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Contrasts of Characters in Go Down,Moses
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作者 谢志超 傅丽莉 《海外英语》 2011年第6X期284-288,共5页
Go Down, Moses is one of William Faulkner's famous novels. It consists of seven stories, most of which have been published earlier as magazine stories. When it first gets published, many reviewers regard it as a c... Go Down, Moses is one of William Faulkner's famous novels. It consists of seven stories, most of which have been published earlier as magazine stories. When it first gets published, many reviewers regard it as a collection of stories, due to its seven loosely jointed stories with their seemingly irrelevant plots and themes. Nowadays, critics take a as a completed novel with different contrastive characters which make the stories more attractive and deepen the plots and themes. 展开更多
关键词 GO Down MOSES WILLIAM FAULKNER contrast character
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Like-simile and metaphor in cooperation:from expressing similarities to expressing contrasts
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作者 Ghsoon Reda 《Language and Semiotic Studies》 2024年第4期504-544,共41页
Cognitive-oriented work on simile has developed out of attempts to pinpoint features distinguishing simile and metaphor.This development has had such consequences as 1)focusing on simile as an analogy-based process an... Cognitive-oriented work on simile has developed out of attempts to pinpoint features distinguishing simile and metaphor.This development has had such consequences as 1)focusing on simile as an analogy-based process and 2)giving very little attention to the way simile and metaphor work together,treating them as independent rather than cooperating phenomena.Addressing these shortcomings,this study examines the ability of non-ironic like-simile to imply contrasts between the asserted source-target similarity and a thought or belief evoked by this similarity,giving rise to context-bound attitudinal and llocutionary implications.In cases of like-simile scaffolded by metaphors,the contrast-based process arises from the cooperation of the two phenomena in the sense that the scenario created by the like-simile rests on manipulating the conceptual metaphor(s)supporting the comparison.The analysis of these cases is placed in the Extended Conceptual Metaphor Theory(ECMT)-a contextual,multilevel theory of figurative language conceptualisation.The contrast-based process,drawn from the model of irony developed within the Lexical Constructional Model(LCM),is added to this theory as a mental-space level activity.Raykowski's sensory schema(a generalized notion of accumulation intuitions)is also added above the imageschema level metaphors,presenting the manipulation of the scaffolding metaphors as based on the expression of this schema. 展开更多
关键词 ECMT contrast LCM like-simile METAPHOR sensory schema
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Leaf functional traits and ecological strategies of common plant species in evergreen broad-leaved forests on Huangshan Mountain
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作者 Ningjie Wang Ting Lv +4 位作者 Lu Wang Shuifei Chen Lei Xie Yanming Fang Hui Ding 《Journal of Forestry Research》 2025年第1期223-243,共21页
The survival strategy of plants is to adjust their functional traits to adapt to the environment.However,these traits and survival strategies of evergreen broad-leaved forest species are not well understood.This study... The survival strategy of plants is to adjust their functional traits to adapt to the environment.However,these traits and survival strategies of evergreen broad-leaved forest species are not well understood.This study examined 10 leaf functional traits(LFTs)of 70 common plant species in an evergreen broad-leaved forest in Huangshan Mountain to decipher their adaptive strategies.The phylogenetic signals of these LFTs were assessed and phylogenetically independent contrasts(PIC)and correlation analyses were carried out.LFTs were analyzed to determine their CSR(C:competitor,S:stress-tolerator,R:ruderal)strategies.The results show that plant species exhibit different leaf functional traits and ecological strategies(nine strategies were identified;the most abundant were S/CS and S/CSR strategies).Some traits showed significant phylogenetic signals,indicating the effect of phylogeny on LFTs to an extent.Trait variations among species suggest distinct adaptation strategies to environmental changes.The study species were mainly clustered on the C-S strategy axis,with a high S component.Species leaning toward the C-strategy end(e.g.,deciduous species),favored a resource acquisition strategy characterized by higher specific leaf area(SLA),greater nutrient contents(N and P),lower leaf dry matter content(LDMC),and reduced nutrient utilization efficiency(C:N and C:P).Conversely,species closer to the S-strategy end(e.g.,evergreen species)usually adopted a resource conservative strategy with trait combinations contrary to those of C-strategy species.Overall,this study corroborated the applicability of the CSR strategy at a local scale and provides insights into the varied trait combinations and ecological strategies employed by plant species to adapt to their environment.These findings contribute to a better understanding of the mechanisms involved in biodiversity maintenance. 展开更多
关键词 Leaf functional traits Phylogenetic signals Phylogenetically independent contrasts CSR ecological strategy
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A Rapid Adaptation Approach for Dynamic Air‑Writing Recognition Using Wearable Wristbands with Self‑Supervised Contrastive Learning
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作者 Yunjian Guo Kunpeng Li +4 位作者 Wei Yue Nam‑Young Kim Yang Li Guozhen Shen Jong‑Chul Lee 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期417-431,共15页
Wearable wristband systems leverage deep learning to revolutionize hand gesture recognition in daily activities.Unlike existing approaches that often focus on static gestures and require extensive labeled data,the pro... Wearable wristband systems leverage deep learning to revolutionize hand gesture recognition in daily activities.Unlike existing approaches that often focus on static gestures and require extensive labeled data,the proposed wearable wristband with selfsupervised contrastive learning excels at dynamic motion tracking and adapts rapidly across multiple scenarios.It features a four-channel sensing array composed of an ionic hydrogel with hierarchical microcone structures and ultrathin flexible electrodes,resulting in high-sensitivity capacitance output.Through wireless transmission from a Wi-Fi module,the proposed algorithm learns latent features from the unlabeled signals of random wrist movements.Remarkably,only few-shot labeled data are sufficient for fine-tuning the model,enabling rapid adaptation to various tasks.The system achieves a high accuracy of 94.9%in different scenarios,including the prediction of eight-direction commands,and air-writing of all numbers and letters.The proposed method facilitates smooth transitions between multiple tasks without the need for modifying the structure or undergoing extensive task-specific training.Its utility has been further extended to enhance human–machine interaction over digital platforms,such as game controls,calculators,and three-language login systems,offering users a natural and intuitive way of communication. 展开更多
关键词 Wearable wristband Self-supervised contrastive learning Dynamic gesture Air-writing Human-machine interaction
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Stochastic Augmented-Based Dual-Teaching for Semi-Supervised Medical Image Segmentation
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作者 Hengyang Liu Yang Yuan +2 位作者 Pengcheng Ren Chengyun Song Fen Luo 《Computers, Materials & Continua》 SCIE EI 2025年第1期543-560,共18页
Existing semi-supervisedmedical image segmentation algorithms use copy-paste data augmentation to correct the labeled-unlabeled data distribution mismatch.However,current copy-paste methods have three limitations:(1)t... Existing semi-supervisedmedical image segmentation algorithms use copy-paste data augmentation to correct the labeled-unlabeled data distribution mismatch.However,current copy-paste methods have three limitations:(1)training the model solely with copy-paste mixed pictures from labeled and unlabeled input loses a lot of labeled information;(2)low-quality pseudo-labels can cause confirmation bias in pseudo-supervised learning on unlabeled data;(3)the segmentation performance in low-contrast and local regions is less than optimal.We design a Stochastic Augmentation-Based Dual-Teaching Auxiliary Training Strategy(SADT),which enhances feature diversity and learns high-quality features to overcome these problems.To be more precise,SADT trains the Student Network by using pseudo-label-based training from Teacher Network 1 and supervised learning with labeled data,which prevents the loss of rare labeled data.We introduce a bi-directional copy-pastemask with progressive high-entropy filtering to reduce data distribution disparities and mitigate confirmation bias in pseudo-supervision.For the mixed images,Deep-Shallow Spatial Contrastive Learning(DSSCL)is proposed in the feature spaces of Teacher Network 2 and the Student Network to improve the segmentation capabilities in low-contrast and local areas.In this procedure,the features retrieved by the Student Network are subjected to a random feature perturbation technique.On two openly available datasets,extensive trials show that our proposed SADT performs much better than the state-ofthe-art semi-supervised medical segmentation techniques.Using only 10%of the labeled data for training,SADT was able to acquire a Dice score of 90.10%on the ACDC(Automatic Cardiac Diagnosis Challenge)dataset. 展开更多
关键词 SEMI-SUPERVISED medical image segmentation contrastive learning stochastic augmented
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Echo contrast medium:How the use of contrast echocardiography(ultrasound contrast agents)can improve patient care
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作者 Kevan English 《World Journal of Methodology》 2025年第3期32-37,共6页
Conventional echocardiography can sometimes pose a challenge to diagnosis due to sub-optimal images.Ultrasound contrast agents(UCAs)have been shown to drastically enhance imaging quality,particularly depicting the lef... Conventional echocardiography can sometimes pose a challenge to diagnosis due to sub-optimal images.Ultrasound contrast agents(UCAs)have been shown to drastically enhance imaging quality,particularly depicting the left ventricular endocardial borders.Their use during echocardiography has become a valuable tool in non-invasive diagnostics.UCAs provide higher-quality images that may ultimately reduce the length of hospital stays and improve patient care.The higher cost associated with UCAs in many situations has been an impediment to frequent use.However,when used as an initial diagnostic test,UCA during rest echocardiogram is more cost-effective than the traditional diagnostic approach,which frequently includes multiple tests and imaging studies to make an accurate diagnosis.They can be easily performed across multiple patient settings and provide optimal images that allow clinicians to make sound medical decisions.This consequently allows for better diagnostic accuracies and improvement in patient care. 展开更多
关键词 Ultrasound contrast agents ECHOCARDIOGRAPHY Myocardial perfusion ULTRASOUND Left ventricle OPTISON DEFINITY SONAZOID Lumason
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Dual-Task Contrastive Meta-Learning for Few-Shot Cross-Domain Emotion Recognition
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作者 Yujiao Tang Yadong Wu +2 位作者 Yuanmei He Jilin Liu Weihan Zhang 《Computers, Materials & Continua》 2025年第2期2331-2352,共22页
Emotion recognition plays a crucial role in various fields and is a key task in natural language processing (NLP). The objective is to identify and interpret emotional expressions in text. However, traditional emotion... Emotion recognition plays a crucial role in various fields and is a key task in natural language processing (NLP). The objective is to identify and interpret emotional expressions in text. However, traditional emotion recognition approaches often struggle in few-shot cross-domain scenarios due to their limited capacity to generalize semantic features across different domains. Additionally, these methods face challenges in accurately capturing complex emotional states, particularly those that are subtle or implicit. To overcome these limitations, we introduce a novel approach called Dual-Task Contrastive Meta-Learning (DTCML). This method combines meta-learning and contrastive learning to improve emotion recognition. Meta-learning enhances the model’s ability to generalize to new emotional tasks, while instance contrastive learning further refines the model by distinguishing unique features within each category, enabling it to better differentiate complex emotional expressions. Prototype contrastive learning, in turn, helps the model address the semantic complexity of emotions across different domains, enabling the model to learn fine-grained emotions expression. By leveraging dual tasks, DTCML learns from two domains simultaneously, the model is encouraged to learn more diverse and generalizable emotions features, thereby improving its cross-domain adaptability and robustness, and enhancing its generalization ability. We evaluated the performance of DTCML across four cross-domain settings, and the results show that our method outperforms the best baseline by 5.88%, 12.04%, 8.49%, and 8.40% in terms of accuracy. 展开更多
关键词 Contrastive learning emotion recognition cross-domain learning DUAL-TASK META-LEARNING
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FedCLCC:A personalized federated learning algorithm for edge cloud collaboration based on contrastive learning and conditional computing
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作者 Kangning Yin Xinhui Ji +1 位作者 Yan Wang Zhiguo Wang 《Defence Technology(防务技术)》 2025年第1期80-93,共14页
Federated learning(FL)is a distributed machine learning paradigm for edge cloud computing.FL can facilitate data-driven decision-making in tactical scenarios,effectively addressing both data volume and infrastructure ... Federated learning(FL)is a distributed machine learning paradigm for edge cloud computing.FL can facilitate data-driven decision-making in tactical scenarios,effectively addressing both data volume and infrastructure challenges in edge environments.However,the diversity of clients in edge cloud computing presents significant challenges for FL.Personalized federated learning(pFL)received considerable attention in recent years.One example of pFL involves exploiting the global and local information in the local model.Current pFL algorithms experience limitations such as slow convergence speed,catastrophic forgetting,and poor performance in complex tasks,which still have significant shortcomings compared to the centralized learning.To achieve high pFL performance,we propose FedCLCC:Federated Contrastive Learning and Conditional Computing.The core of FedCLCC is the use of contrastive learning and conditional computing.Contrastive learning determines the feature representation similarity to adjust the local model.Conditional computing separates the global and local information and feeds it to their corresponding heads for global and local handling.Our comprehensive experiments demonstrate that FedCLCC outperforms other state-of-the-art FL algorithms. 展开更多
关键词 Federated learning Statistical heterogeneity Personalized model Conditional computing Contrastive learning
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Equilibrium phase images of the liver using a contrast-enhancement boost instead of the portal vein phase
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作者 Yuji Tachibana Kenichiro Otsuka +1 位作者 Tomoaki Shiroo Yoshiki Asayama 《World Journal of Radiology》 2025年第2期28-37,共10页
BACKGROUND Three-phase dynamic computed tomography imaging is particularly useful in the liver region.However,dynamic imaging with contrast media has the disadvantage of increased radiation exposure due to multiple im... BACKGROUND Three-phase dynamic computed tomography imaging is particularly useful in the liver region.However,dynamic imaging with contrast media has the disadvantage of increased radiation exposure due to multiple imaging sessions.We hypothesized that the contrast enhancement boost(CE-boost)technique could be used to enhance the contrast in equilibrium phase(EP)images and produce enhancement similar to that of portal vein phase(PVP)images,and if this is possible,EP imaging could play the same role as PVP imaging.We also speculated that this might allow the conversion of three-phase dynamic imaging to biphasic dynamic imaging,reducing patients’radiation exposure.AIM To determine if the CE-boost of EP,CE-boost(EP)is useful compared to a conventional image.METHODS We retrospectively analyzed the cases of 52 patients who were diagnosed with liver cancer between January 2016 and October 2022 at our institution.From these computed tomography images,CE-boost images were generated from the EP and plane images.We compared the PVP,EP,and CE-boost(EP)for blood vessels and hepatic parenchyma based on the contrast-to-noise ratio(CNR),signal-to-noise ratio,and figure-of-merit(FOM).Visual assessments were also performed for vessel visualization,lesion conspicuity,and image noise.RESULTS The CE-boost(EP)images showed significant superiority compared to the PVP images in the CNR,signal-to-noise ratio,and FOM except regarding the hepatic parenchyma.No significant differences were detected in CNR or FOM comparisons within the hepatic parenchyma(P=0.62,0.67).The comparison of the EP and CE-boost(EP)images consistently favored CE-boost(EP).Regarding the visual assessment,the CE-boost(EP)images were significantly superior to the PVP images in lesion conspicuity,and the PVP in image noise.The CE-boost(EP)images were significantly better than the EP images in the vessel visualization of segmental branches of the portal vein and lesion conspicuity,and the EP in image noise.CONCLUSION The image quality of CE-boost(EP)images was comparable or superior to that of conventional PVP and EP.CEboost(EP)images might provide information comparable to the conventional PVP. 展开更多
关键词 LIVER Computed tomography Contrast enhancement boost Image quality Lesion conspicuity
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