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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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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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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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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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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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Effect of magnetic resonance imaging in liver metastases
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作者 Xing-Liang Huang Xiao-Dong Wang +2 位作者 Zhao-Miao Gong Yan-Feng Zheng Jing-Xin Mao 《World Journal of Gastroenterology》 SCIE CAS 2024年第1期112-114,共3页
This letter to the editor is a commentary on a study titled"Liver metastases:The role of magnetic resonance imaging."Exploring a noninvasive imaging evaluation system for the biological behavior of hepatocel... This letter to the editor is a commentary on a study titled"Liver metastases:The role of magnetic resonance imaging."Exploring a noninvasive imaging evaluation system for the biological behavior of hepatocellular carcinoma(HCC)is the key to achieving precise diagnosis and treatment and improving prognosis.This review summarizes the role of magnetic resonance imaging in the detection and evaluation of liver metastases,describes its main imaging features,and focuses on the added value of the latest imaging tools(such as T1 weighted in phase imaging,T1 weighted out of phase imaging;diffusion-weighted imaging,T2 weighted imaging).In this study,I investigated the necessity and benefits of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid for HCC diagnostic testing and prognostic evaluation. 展开更多
关键词 Liver metastases Magnetic resonance imaging Liver-specific contrast agents Gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid Hepatocellular carcinoma Hepatobiliary contrast agents
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Influence of Irregular Coastlines on a Tornadic Mesovortex in the Pearl River Delta during the Monsoon Season. Part I: Pre-storm Environment and Storm Evolution
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作者 Lanqiang BAI Dan YAO +4 位作者 Zhiyong MENG Yu ZHANG Xianxiang HUANG Zhaoming LI Xiaoding YU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1115-1131,共17页
The Pearl River Delta(PRD),a tornado hotspot,forms a distinct trumpet-shaped coastline that concaves toward the South China Sea.During the summer monsoon season,low-level southwesterlies over the PRD’s sea surface te... The Pearl River Delta(PRD),a tornado hotspot,forms a distinct trumpet-shaped coastline that concaves toward the South China Sea.During the summer monsoon season,low-level southwesterlies over the PRD’s sea surface tend to be turned toward the west coast,constituting a convergent wind field along with the landward-side southwesterlies,which influences regional convective weather.This two-part study explores the roles of this unique land–sea contrast of the trumpet-shaped coastline in the formation of a tornadic mesovortex within monsoonal flows in this region.Part I primarily presents observational analyses of pre-storm environments and storm evolutions.The rotating storm developed in a lowshear environment(not ideal for a supercell)under the interactions of three air masses under the influence of the land–sea contrast,monsoon,and storm cold outflows.This intersection zone(or“triple point”)is typically characterized by local enhancements of ambient vertical vorticity and convergence.Based on a rapid-scan X-band phased-array radar,finger-like echoes were recognized shortly after the gust front intruded on the triple point.Developed over the triple point,they rapidly wrapped up with a well-defined low-level mesovortex.It is thus presumed that the triple point may have played roles in the mesovortex genesis,which will be demonstrated in Part II with multiple sensitivity numerical simulations.The findings also suggest that when storms pass over the boundary intersection zone in the PRD,the expected possibility of a rotating storm occurring is relatively high,even in a low-shear environment.Improved knowledge of such environments provides additional guidance to assess the regional tornado risk. 展开更多
关键词 TORNADO mesovortex surface boundary land–sea contrast MONSOON
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Attribution of Biases of Interhemispheric Temperature Contrast in CMIP6 Models
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作者 Shiyan ZHANG Yongyun HU +1 位作者 Jiankai ZHANG Yan XIA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期325-340,共16页
One of the basic characteristics of Earth's modern climate is that the Northern Hemisphere(NH) is climatologically warmer than the Southern Hemisphere(SH). Here, model performances of this basic state are examined... One of the basic characteristics of Earth's modern climate is that the Northern Hemisphere(NH) is climatologically warmer than the Southern Hemisphere(SH). Here, model performances of this basic state are examined using simulation results from 26 CMIP6 models. Results show that the CMIP6 models underestimate the contrast in interhemispheric surface temperatures on average(0.8 K for CMIP6 mean versus 1.4 K for reanalysis data mean), and that there is a large intermodel spread, ranging from -0.7 K to 2.3 K. A box model energy budget analysis shows that the contrast in interhemispheric shortwave absorption at the top of the atmosphere, the contrast in interhemispheric greenhouse trapping, and the crossequatorial northward ocean heat transport, are all underestimated in the multimodel mean. By examining the intermodel spread, we find intermodel biases can be tracked back to biases in midlatitude shortwave cloud forcing in AGCMs. Models with a weaker interhemispheric temperature contrast underestimate the shortwave cloud reflection in the SH but overestimate the shortwave cloud reflection in the NH, which are respectively due to underestimation of the cloud fraction over the SH extratropical ocean and overestimation of the cloud liquid water content over the NH extratropical continents.Models that underestimate the interhemispheric temperature contrast exhibit larger double ITCZ biases, characterized by excessive precipitation in the SH tropics. Although this intermodel spread does not account for the multimodel ensemble mean biases, it highlights that improving cloud simulation in AGCMs is essential for simulating the climate realistically in coupled models. 展开更多
关键词 interhemispheric temperature contrast energy balance shortwave cloud forcing ITCZ CMIP6 AGCM
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Influence of substrate effect on near-field radiative modulator based on biaxial hyperbolic materials
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作者 刘睿一 刘皓佗 +2 位作者 胡杨 崔峥 吴小虎 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期56-64,共9页
Relative rotation between the emitter and receiver could effectively modulate the near-field radiative heat transfer(NFRHT)in anisotropic media.Due to the strong in-plane anisotropy,natural hyperbolic materials can be... Relative rotation between the emitter and receiver could effectively modulate the near-field radiative heat transfer(NFRHT)in anisotropic media.Due to the strong in-plane anisotropy,natural hyperbolic materials can be used to construct near-field radiative modulators with excellent modulation effects.However,in practical applications,natural hyperbolic materials need to be deposited on the substrate,and the influence of substrate on modulation effect has not been studied yet.In this work,we investigate the influence of substrate effect on near-field radiative modulator based onα-MoO_(3).The results show that compared to the situation without a substrate,the presence of both lossless and lossy substrate will reduce the modulation contrast(MC)for different film thicknesses.When the real or imaginary component of the substrate permittivity increases,the mismatch of hyperbolic phonon polaritons(HPPs)weakens,resulting in a reduction in MC.By reducing the real and imaginary components of substrate permittivity,the MC can be significantly improved,reaching 4.64 forε_(s)=3 at t=10 nm.This work indicates that choosing a substrate with a smaller permittivity helps to achieve a better modulation effect,and provides guidance for the application of natural hyperbolic materials in the near-field radiative modulator. 展开更多
关键词 near-field radiative modulator substrate effect hyperbolic material modulation contrast
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Gastrointestinal contrast-enhanced ultrasonography for diagnosis and treatment of peptic ulcer in children
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作者 Yu-Hua Zhang Zhi-Hua Xu +1 位作者 Shuang-Shuang Ni Hong-Xia Luo 《World Journal of Gastroenterology》 SCIE CAS 2024年第7期705-713,共9页
BACKGROUND The detection rate of peptic ulcer in children is improving,with development of diagnostic procedures.Gastroscopy is the gold standard for the diagnosis of peptic ulcer,but it is an invasive procedure.Gastr... BACKGROUND The detection rate of peptic ulcer in children is improving,with development of diagnostic procedures.Gastroscopy is the gold standard for the diagnosis of peptic ulcer,but it is an invasive procedure.Gastrointestinal contrast-enhanced ultrasonography(CEUS)has the advantages of being painless,noninvasive,nonradioactive,easy to use,and safe.AIM To investigate the clinical value of CEUS for diagnosis and treatment of peptic ulcer in children.METHODS We investigated 43 children with digestive tract symptoms in our hospital from January 2021 to June 2022.All children were examined by routine ultrasound,gastrointestinal CEUS,and gastroscopy.The pathological results of gastroscopy were taken as the gold standard.Routine ultrasonography was performed before gastrointestinal CEUS.Conventional ultrasound showed the thickness of the gastroduodenal wall,gastric peristalsis,and the adjacent organs and tissues around the abdominal cavity.Gastrointestinal CEUS recorded the thickness of the gastroduodenal wall;the size,location and shape of the ulcer;gastric peristalsis;and adjacent organs and tissues around the abdominal cavity.The results of routine ultrasound and gastrointestinal ultrasound were compared with those of gastroscopy to evaluate the diagnostic results and coincidence rate of routine ultrasound and gastrointestinal CEUS.All children received informed consent from their guardians for CEUS.This study was reviewed and approved by the hospital medical ethics committee.RESULTS Among the 43 children,17(15 male,2 female)were diagnosed with peptic ulcer by gastroscopy.There were 26 children with nonpeptic ulcer.There were eight cases of peptic ulcer and 35 of nonpeptic ulcer diagnosed by conventional ultrasound.The diagnostic coincidence rate of peptic ulcer in children diagnosed by conventional ultrasound was 79.1%(34/43),which was significantly different from that of gastroscopy(P=0.033).It indicates that the coincidence rate of gastrointestinal contrast-enhanced ultrasound and gastroscope is low.Fifteen cases of peptic ulcer and 28 of nonpeptic ulcer were diagnosed by CEUS.The diagnostic coincidence rate of peptic ulcer in children was 95.3%(41/43).There was no significant difference between CEUS and gastroscopy(P=0.655).It indicates that the coincidence rate of gastrointestinal contrast-enhanced ultrasound and gastroscope is high.CONCLUSION Gastrointestinal CEUS has a high coincidence rate in the diagnosis of peptic ulcer in children,and can be used as a preliminary examination method. 展开更多
关键词 Contrast-enhanced ultrasound Peptic ulcer CHILDREN Gastrointestinal tract Abdominal pain Acoustic contrast agent
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Theory and verification of moiréfringes for x-ray three-phase grating interferometer
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作者 单雨征 葛永帅 +5 位作者 杨君 郭大育 蔡学宝 刘晓珂 侯晓文 郭金川 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期532-540,共9页
Dual-phase and three-phase grating x-ray interference is a promising new technique for grating-based x-ray differential phase contrast imaging.Dual-phase grating interferometers have been relatively completely studied... Dual-phase and three-phase grating x-ray interference is a promising new technique for grating-based x-ray differential phase contrast imaging.Dual-phase grating interferometers have been relatively completely studied and discussed.In this paper,the corresponding imaging fringe formula of the three-phase grating interferometer is provided.At the same time,the similarities and differences between the three-phase grating interferometer and the dual-phase grating interferometer are investigated and verified,and that the three-phase grating interferometer can produce large-period moiréfringes without using the analyzing grating is demonstrated experimentally.Finally,a simple method of designing three-phase grating and multi-grating imaging systems from geometric optics based on the thin-lens theory of gratings is presented.These theoretical formulas and experimental results provide optimization tools for designing three-phase grating interferometer systems. 展开更多
关键词 x-ray phase contrast phase grating moiréfringe
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Optical design of a novel near-infrared phase contrast imaging(NI-PCI)diagnostic on the HL-2A tokamak
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作者 徐皓 龚少博 +11 位作者 余羿 许敏 兰涛 王志斌 石中兵 聂林 赵光义 刘灏 周艺轩 袁子豪 肖晨雨 陈坚 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期31-37,共7页
The optical design of near-infrared phase contrast imaging(NI-PCI)diagnosis on HL-2A is introduced in this paper.This scheme benefits from the great progress of near-infrared laser technology and is a broadening of tr... The optical design of near-infrared phase contrast imaging(NI-PCI)diagnosis on HL-2A is introduced in this paper.This scheme benefits from the great progress of near-infrared laser technology and is a broadening of traditional phase contrast technology.This diagnostic can work as a keen tool to measure plasma wavenumber spectra by inferring string-integrated plasma density fluctuations.Design of both the front optical path which is the path before the laser transmitting into the tokamak plasma and the rear optics which is the path after the laser passing through the plasma is detailed.The 1550 nm laser is chosen as the probe beam and highprecision optical components are designed to fit the laser beam,in which a phase plate with a 194-nm-deep silver groove is the key.Compared with the conventional 10.6μm laser-based PCI system on HL-2A,NI-PCI significantly overcomes the unwanted phase scintillation effect and promotes the measurement capability of high-wavenumber turbulence with an increased maximal measurable wavenumber from 15 cm^(-1)to 32.6 cm^(-1). 展开更多
关键词 phase contrast imaging near infrared laser plasma laser diagnostic
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Recommendation Method for Contrastive Enhancement of Neighborhood Information
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作者 Hairong Wang Beijing Zhou +1 位作者 Lisi Zhang He Ma 《Computers, Materials & Continua》 SCIE EI 2024年第1期453-472,共20页
Knowledge graph can assist in improving recommendation performance and is widely applied in various person-alized recommendation domains.However,existing knowledge-aware recommendation methods face challenges such as ... Knowledge graph can assist in improving recommendation performance and is widely applied in various person-alized recommendation domains.However,existing knowledge-aware recommendation methods face challenges such as weak user-item interaction supervisory signals and noise in the knowledge graph.To tackle these issues,this paper proposes a neighbor information contrast-enhanced recommendation method by adding subtle noise to construct contrast views and employing contrastive learning to strengthen supervisory signals and reduce knowledge noise.Specifically,first,this paper adopts heterogeneous propagation and knowledge-aware attention networks to obtain multi-order neighbor embedding of users and items,mining the high-order neighbor informa-tion of users and items.Next,in the neighbor information,this paper introduces weak noise following a uniform distribution to construct neighbor contrast views,effectively reducing the time overhead of view construction.This paper then performs contrastive learning between neighbor views to promote the uniformity of view information,adjusting the neighbor structure,and achieving the goal of reducing the knowledge noise in the knowledge graph.Finally,this paper introduces multi-task learning to mitigate the problem of weak supervisory signals.To validate the effectiveness of our method,experiments are conducted on theMovieLens-1M,MovieLens-20M,Book-Crossing,and Last-FM datasets.The results showthat compared to the best baselines,our method shows significant improvements in AUC and F1. 展开更多
关键词 Contrastive learning knowledge graph recommendation method
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Simplified liver imaging reporting and data system for the diagnosis of hepatocellular carcinoma on gadoxetic acid-enhanced magnetic resonance imaging
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作者 Rong Lyu Wei-Juan Hu +3 位作者 Di Wang Jiao Wang Yu-Bing Ye Ke-Feng Jia 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2439-2448,共10页
BACKGROUND The liver imaging reporting and data system(LI-RADS)diagnostic table has 15 cells and is too complex.The diagnostic performance of LI-RADS for hepatocellular carcinoma(HCC)is not satisfactory on gadoxetic a... BACKGROUND The liver imaging reporting and data system(LI-RADS)diagnostic table has 15 cells and is too complex.The diagnostic performance of LI-RADS for hepatocellular carcinoma(HCC)is not satisfactory on gadoxetic acid-enhanced magnetic resonance imaging(EOB-MRI).AIM To evaluate the ability of the simplified LI-RADS(sLI-RADS)to diagnose HCC on EOB-MRI.METHODS A total of 331 patients with 356 hepatic observations were retrospectively analysed.The diagnostic performance of sLI-RADS A-D using a single threshold was evaluated and compared with LI-RADS v2018 to determine the optimal sLIRADS.The algorithms of sLI-RADS A-D are as follows:The single threshold for sLI-RADS A and B was 10 mm,that is,classified observations≥10mm using an algorithm of 10-19 mm observations(sLI-RADS A)and≥20 mm observations(sLI-RADS B)in the diagnosis table of LI-RADS v2018,respectively,while the classification algorithm remained unchanged for observations<10 mm;the single threshold for sLI-RADS C and D was 20 mm,that is,for<20 mm observations,the algorithms for<10 mm observations(sLI-RADS C)and 10-19 mm observations(sLI-RADS D)were used,respectively,while the algorithm remained unchanged for observations≥20 mm.With hepatobiliary phase(HBP)hypointensity as a major feature(MF),the final sLI-RADS(F-sLI-RADS)was formed according to the optimal sLI-RADS,and its diagnostic performance was evaluated.The times needed to classify the observations according to F-sLIRADS and LI-RADS v2018 were compared.RESULTS The optimal sLI-RADS was sLI-RADS D(with a single threshold of 20 mm),because its sensitivity was greater than that of LI-RADS v2018(89.8%vs 87.0%,P=0.031),and its specificity was not lower(89.4%vs 90.1%,P>0.999).With HBP hypointensity as an MF,the sensitivity of F-sLI-RADS was greater than that of LI-RADS v2018(93.0%vs 87.0%,P<0.001)and sLI-RADS D(93.0%vs 89.8%,P=0.016),without a lower specificity(86.5%vs 90.1%,P=0.062;86.5%vs 89.4%,P=0.125).Compared with that of LI-RADS v2018,the time to classify lesions according to FsLI-RADS was shorter(51±21 s vs 73±24 s,P<0.001).CONCLUSION The use of sLI-RADS with HBP hypointensity as an MF may improve the sensitivity of HCC diagnosis and reduce lesion classification time. 展开更多
关键词 Hepatocellular carcinoma Magnetic resonance imaging LIVER DIAGNOSIS Contrast agent
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Laser speckle contrast imaging to predict the effect of temporary spinal cord stimulation in postherpetic neuralgia patients: A prospective observational study
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作者 Xiang Huang Dacheng Tang +3 位作者 Pan Chen Lumiao Chen Xiaohong Li Xiaoping Wang 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第1期69-75,共7页
Temporary spinal cord stimulation(tSCS)can effectively reduce the pain and severity of postherpetic neuralgia(PHN).However,there are no effective and objective methods for predicting the effects of tSCS on PHN.Laser s... Temporary spinal cord stimulation(tSCS)can effectively reduce the pain and severity of postherpetic neuralgia(PHN).However,there are no effective and objective methods for predicting the effects of tSCS on PHN.Laser speckle contrast imaging(LSCI)is frequently used in neurology to evaluate the effectiveness of treatment.To assess the accuracy of LSCI in predicting the impact of tSCS on PHN,14 adult patients receiving tSCS treatments for spinal nerve-innervated(C6-T2)PHN participated in this observational study.Visual analog scale(VAS)assessments and LSCI bloodflow images of the-ngers were recorded after the tSCS procedure.The results showed that the VAS scores of all patients decreased signi-cantly.Moreover,the bloodflow index(BFI)values were signi-cantly higher than they were before the procedure.Increased bloodflow and pain alleviation were positively correlated.The-ndings indicated that spinal nerve PHN(C6-T2)was signi-cantly reduced by tSCS.Pain alleviation by tSCS was positively correlated with increased bloodflow in the hand.The effect of tSCS on PHN may thus be predicted using an independent and consistent indicator such as LSCI. 展开更多
关键词 Laser speckle contrast imaging temporary spinal cord stimulation postherpetic neuralgia
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Improved Weighted Local Contrast Method for Infrared Small Target Detection
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作者 Pengge Ma Jiangnan Wang +3 位作者 Dongdong Pang Tao Shan Junling Sun Qiuchun Jin 《Journal of Beijing Institute of Technology》 EI CAS 2024年第1期19-27,共9页
In order to address the problem of high false alarm rate and low probabilities of infrared small target detection in complex low-altitude background,an infrared small target detection method based on improved weighted... In order to address the problem of high false alarm rate and low probabilities of infrared small target detection in complex low-altitude background,an infrared small target detection method based on improved weighted local contrast is proposed in this paper.First,the ratio information between the target and local background is utilized as an enhancement factor.The local contrast is calculated by incorporating the heterogeneity between the target and local background.Then,a local product weighted method is designed based on the spatial dissimilarity between target and background to further enhance target while suppressing background.Finally,the location of target is obtained by adaptive threshold segmentation.As experimental results demonstrate,the method shows superior performance in several evaluation metrics compared with six existing algorithms on different datasets containing targets such as unmanned aerial vehicles(UAV). 展开更多
关键词 infrared small target unmanned aerial vehicles(UAV) local contrast target detection
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