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Single 5-nm quantum dot detection via microtoroid optical resonator photothermal microscopy

Light(Science & Applications) 2024年第10期13卷 2145-2155页

作者： Shuang Hao Sartanee suebka judith su Wyant College of Optical Sciences University of ArizonaTucsonAZ 85721USA Wyant College of Optical Sciences and Department of Biomedical Engineering University of ArizonaTucsonAZ 85721USA

Label-free detection techniques for single particles and molecules play an important role in basic science,disease diagnostics,and nanomaterial *** fluorescence-based methods are tools for single molecule detection and imaging,they are limited by available molecular probes and photoblinking and *** microscopy has emerged as a label-free imaging technique capable of detecting individual nanoabsorbers with high *** gallery mode(WGM)microresonators can confine light in a small volume for enhanced light-matter interaction and thus are a promising ultra-sensitive photothermal microscopy ***,microtoroid optical resonators were combined with photothermal microscopy to detect 250 nm iong gold nanorods and 100 nm long ***,we combine microtoroids with photothermal microscopy to spatially detect single 5 nm diameter quantum dots(QDs)with a signal-to-noise ratio exceeding 10*.Photothermal images were generated by point-by-point scanning of the pump *** particle detection was confrmed for 18 nm QDs by high sensitivity fluorescence imaging and for 5 nm QDs via comparison with *** system demonstrates the capability to detect a minimum heat dissipation of o.75 *** achieve this,we integrated our microtoroid based photothermal microscopy setup with a low amplitude modulated pump laser and utilized the proportional-integral-derivative controller output as the photothermal signal source to reduce noise and enhance signal *** heat dissipation of these QDs is below that from single dye *** anticipate that our work will have application in a wide variety of fields,including the biological sciences,nanotechnology,materials science,chemistry and medicine.

关键词： pump resonator quantum

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Ultra-high-Q free-space coupling to microtoroid resonators

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Light(Science & Applications) 2024年第4期13卷 682-695页

作者： Sartanee suebka Euan McLeod judith su Wyant College of Optical Sciences University of ArizonaTucsonAZUSA Department of Biomedical Engineering University of ArizonaTucsonAZUSA

Whispering gallery mode(WGM)microtoroid resonators are one of the most sensitive biochemical sensors in existence,capable of detecting single *** main barrier for translating these devices out of the laboratory is that light is evanescently coupled into these devices though a tapered optical *** hinders translation of these devices as the taper is fragile,suffers from mechanical vibration,and requires precise ***,we eliminate the need for an optical fiber by coupling light into and out from a toroid via free-space coupling and monitoring the scattered resonant light.A single long working distance objective lens combined with a digital micromirror device(DMD)was used for light injection,scattered light collection,and *** obtain Q-factors as high as 1:6´108 with this *** induced transparency(EIT)-like and Fano resonances were observed in a single cavity due to indirect coupling in free *** enables improved sensing *** large effective coupling area(~10μm in diameter for numerical aperture=0.14)removes the need for precise *** performance was verified by combining the system with the frequency locked whispering evanescent resonator(FLOWER)approach to perform temperature sensing experiments.A thermal nonlinear optical effect was examined by tracking the resonance through FLOWER while adjusting the input *** believe that this work will be a foundation for expanding the implementation of WGM microtoroid resonators to real-world applications.

关键词： coupling scattered precise

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Portable and sensitive air pollution monitoring

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Light(Science & Applications) 2018年第1期7卷 987-988页

作者： judith su Department of Biomedical Engineering and College of Optical Sciences University of ArizonaTucsonAZ 85721USA

A compact optical nanofiber sensor enables detection of 100 nm particles in the *** device improves our ability to track air quality with high spatiotemporal *** pollution has enormous health and economic costs,causing an estimated 7 million deaths per year1 and costing US$225 billion globally in 2013 according to the most recent data from the World Health Organization(WHO)and World Bank,*** this impact,air pollution levels continue to increase,with 92%of the world’s population living in environments in which WHO air quality guidelines are not met3.

关键词： pollution globally enable

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Label-free detection of single nanoparticles and biological molecules using microtoroid optical resonators

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Light(Science & Applications) 2016年第1期5卷 863-868页

作者： judith su Alexander FG Goldberg Brian M Stoltz Division of Biology and Biological Engineering California Institute of TechnologyPasadenaCAUSA Divison of Chemistry and Chemical Engineering California Institute of TechnologyPasadenaCAUSA

Single-molecule detection is one of the fundamental challenges of modern *** experiments often use labels that can be expensive,difficult to produce,and for small analytes,might perturb the molecular events being *** size plays an important role in determining *** we use laser-frequency locking in the context of sensing to improve the signal-to-noise ratio of microtoroid optical resonators to the extent that single nanoparticles 2.5 nm in radius,and 15.5 kDa molecules are detected in aqueous solution,thereby bringing these detectors to the size limits needed for detecting the key macromolecules of the *** results,covering several orders of magnitude of particle radius(100 nm to 2 nm),agree with the‘reactive’model prediction for the frequency shift of the resonator upon particle *** confirms that the main contribution of the frequency shift for the resonator upon particle binding is an increase in the effective path length due to part of the evanescent field coupling into the adsorbed *** anticipate that our results will enable many applications,including more sensitive medical diagnostics and fundamental studies of single receptor–ligand and protein–protein interactions in real time.

关键词： biosensing frequency locking label-free microtoroid single molecule

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Dark mode plasmonic optical microcavity biochemical sensor

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Photonics Research 2019年第8期7卷 939-947页

作者： CHENG LI LEI CHEN EUAN MCLEOD judith su College of Optical Sciences University of ArizonaTucsonArizona85721USA State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing100876China Department of Biomedical Engineering University of ArizonaTucsonArizona85721USA

Whispering gallery mode(WGM) microtoroid optical resonators have been effectively used to sense low concentrations of biomolecules down to the single molecule limit. Optical WGM biochemical sensors such as the microtoroid operate by tracking changes in resonant frequency as particles enter the evanescent near field of the ***, gold nanoparticles have been coupled to WGM resonators to increase the magnitude of resonance shifts via plasmonic enhancement of the electric field. However, this approach results in increased scattering from the WGM, which degrades its quality(Q) factor, making it less sensitive to extremely small frequency shifts caused by small molecules or protein conformational changes. Here, we show using simulation that precisely positioned trimer gold nanostructures generate dark modes that suppress radiation loss and can achieve high (> 10~6) Q with an electric-field intensity enhancement of 4300, which far exceeds that of a single rod(~2500 times). Through an overall evaluation of a combined enhancement factor, which includes the Q factor of the system, the sensitivity of the trimer system was improved 105× versus 84× for a single rod. Further simulations demonstrate that unlike a single rod system, the trimer is robust to orientation changes and has increased capture area. We also conduct stability tests to show that small positioning errors do not greatly impact the result.

关键词： WGM Dark mode plasmonic microcavity

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Simulating robust far-field coupling to traveling waves in large three-dimensional nanostructured high-Q microresonators

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Photonics Research 2019年第9期7卷 967-976页

作者： LEI CHEN CHENG LI YU-MIN LIU judith su EUAN MCLEOD State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing100876China College of Optical Sciences University of ArizonaTucsonArizona85721USA Department of Biomedical Engineering University of ArizonaTucsonArizona85721USA

Ultra-high quality(Q) whispering gallery mode(WGM) microtoroid optical resonators have demonstrated highly sensitive biomolecular detection down to the single molecule limit;however, the lack of a robust coupling method has prevented their widespread adoption outside the laboratory. We demonstrate through simulation that a phased array of nanorods can enable free-space coupling of light both into and out of a microtoroid while maintaining a high Q. To simulate large nanostructured WGM resonators, we developed a new approach known as FloWBEM,which is an efficient and compact 3D wedge model with custom boundary conditions that accurately simulate the resonant Fano interference between the traveling WGM waves and a nanorod array. Depending on the excitation conditions, we find loaded Q factors of the driven system as high as 2.1 × 10~7 and signal-to-background ratios as high as 3.86%, greater than the noise levels of many commercial detectors. These results can drive future experimental implementation.

关键词： domain Simulating robust far-field coupling to traveling waves in large three-dimensional nanostructured high-Q microresonators WGM

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基于小波变换的心音包络提取算法及应用

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中国组织工程研究与临床康复 2011年第30期15卷 5615-5619页

作者：周酥朱蒂吴效明黄岳山华南理工大学生物医学工程系广东省广州市510006

背景:心音信号包含了大量心脏瓣膜活动的生理信息,心音分析对诊断心脏疾病具有重要的临床意义。目的:旨在通过心音的包络提取,分析心音信号的各种特征,进而判断心音中是否包含杂音,以改善传统听诊技术高度依赖医生经验、听诊范围受限的... 详细信息

背景:心音信号包含了大量心脏瓣膜活动的生理信息,心音分析对诊断心脏疾病具有重要的临床意义。目的:旨在通过心音的包络提取,分析心音信号的各种特征,进而判断心音中是否包含杂音,以改善传统听诊技术高度依赖医生经验、听诊范围受限的缺点。方法:提出了一种采用小波变换来提取心音包络的方法,通过与采用希尔伯特-黄变换、数学形态学、平均香农能量等心音包络求解方法进行对比,证明这种方法具有算法简便、曲线光滑、特征点突出等优点。结果与结论:将该方法用于临床真实心音的包络提取,利用支持向量机来训练所提取心音包络的面积和小波能量两个特征参数,判别心音信号是否明显包含杂音。选用35例心音数据对算法进行验证,结果表明该算法的准确率达到95%,具有很强的实用性。

关键词：心音小波变换包络提取支持向量机特征参数

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汉娜·阿伦特宣判的死刑

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文学与文化 2014年第2期 59-68页

作者：朱迪斯.巴特勒苏培美国加州大学伯克利分校修辞与比较文学系北京第二外国语学院跨文化研究院

汉娜·阿伦特同意对艾希曼的最终审判,但她怀疑审判本身的戏剧性。她反对把艾希曼当作替罪羊。《艾希曼在耶路撒冷》风格特异,观点鲜明,但是文本充满了内在矛盾,可见阿伦特对一场相当复杂的政治事件持一种异常复杂的矛盾情绪。艾希曼没... 详细信息

汉娜·阿伦特同意对艾希曼的最终审判,但她怀疑审判本身的戏剧性。她反对把艾希曼当作替罪羊。《艾希曼在耶路撒冷》风格特异,观点鲜明,但是文本充满了内在矛盾,可见阿伦特对一场相当复杂的政治事件持一种异常复杂的矛盾情绪。艾希曼没有义务为集体犯罪承受死刑,而为他定罪的人们对于判处死刑的理由又语焉不详。其中矛盾重重,意见彼此冲突,以及死刑在复仇冲动和不同正义标准之间戏剧性地摇摆,引发纷争不断,莫衷一是。

关键词：死刑判决正义批判集体犯罪

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江西池江盆地上古新统一种类似偶蹄类的古有蹄类(英文)

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古脊椎动物学报 2007年第4期45卷 278-286页

作者：丁素因孟津李茜王元青童永生 judith A.SCHIEBOUT Paul L.KOCH William C.CLYDE Gabriel J.BOWEN 美国路易斯安那州立大学自然科学博物馆巴吞鲁日la70803 美国自然历史博物馆纽约ny10024 中国科学院古脊椎动物与古人类研究所北京100044 美国加利福尼亚大学地球科学系圣克鲁斯ca95064 美国新罕布什尔大学地球科学系达勒姆nh03824 美国犹他大学生物系盐湖城ut84112

奇蹄类和偶蹄类是现代的主要有蹄动物,它们的起源一直是古哺乳动物学界关心的课题。近年来的发现表明,在早始新世奇蹄类出现之前,亚洲已有牙齿形态与奇蹄类相近的有蹄类存在。偶蹄类的情况可能也是如此,这里记述的古新世新村里赣蹄兽就... 详细信息

奇蹄类和偶蹄类是现代的主要有蹄动物,它们的起源一直是古哺乳动物学界关心的课题。近年来的发现表明,在早始新世奇蹄类出现之前,亚洲已有牙齿形态与奇蹄类相近的有蹄类存在。偶蹄类的情况可能也是如此,这里记述的古新世新村里赣蹄兽就是一个明证。新村里赣蹄兽(Ganungulatum xincunliense *** ***.)化石产于江西大余青龙镇新村里附近的晚古新世池江组滥泥坑段,化石地点编号为72035(76)。在同一地点还发现南方古对锥兽Archaeoryctes notialis Zheng,1979和滥泥坑赣脊兽Ganolophus lanikenensis Zhang,1979。赣蹄兽材料为一对不完整的下颌骨,右下颌骨保存i2-3,c和p4-m3,左下颌骨存有p3-m3(IVPP V 14154)。其特征是下齿式为3?·1·4·3;i3与颊齿列平行,i2稍有些斜;犬齿小;p3有初始的跟座,p4三角座明显,跟座小;下臼齿为丘形齿,牙齿由m1向m3增大,三角座前后收缩,下前尖位于舌侧,并靠近下后尖,下后尖较下原尖靠后,m3有一增大的跟座,跟盆向舌侧开放。新村里赣蹄兽下颊齿低冠,呈丘形齿,下臼齿三角座前后收缩和m3下次小尖增大等特征,说明了赣蹄兽与亚洲古新世地层中常见的真兽类,例如(?)兽类、裂齿类、中兽类和全齿类不同,而与Prothero et al.(1988)提出的有蹄类(Ungulata)牙齿相似,表现出与某些有蹄类密切相关。与已知的晚白垩世和古新世有蹄类比较,赣蹄兽与"踝节类"("condylarths")中的豕齿类(hyopsodontids)和眛兽类(mioclaenids)比较相近。但从其下犬齿小,p4相对较大,臼齿化程度高,以及下臼齿下前尖在舌面位置和与下后尖接近等特征来看,赣蹄兽更接近mioclaenids。修仁古亚兽(Palasiodon siurensis)是亚洲仅有的mioclaenid,产于广东南雄盆地下古新统上湖组,但在牙齿形态上容易与这里记述的赣蹄兽区别,古亚兽下颊齿短宽,m3很退化。与其他已知的mioclaenids比较,赣蹄兽在大小上和牙齿形态上与北美Torrejonian的Litaletes disjunctus最接近,两者都有小的匙状的下犬齿,相对臼齿化的p4,下臼齿下前尖向舌侧位移,前、后齿带无或很弱,m3增大。但赣蹄兽明显不同于,***,前者p3更小,更简单,p4下前尖更小,跟座不成盆状,下臼齿下前尖较大,更加舌位,并与下后尖靠近,下后尖在下原尖的后侧,m3下内尖不明显。由此可见,赣蹄兽下颊齿和已知的"踝节类"是可以区别的,但更重要的区别点是在下颌骨的前面部分。在与arctocyonids、hyopsodontids和phenacodontids等"踝节类"对比时,我们发现赣蹄兽和"踝节类"之间的重大差异在于下门齿的排列上。这些"踝节类"的三个下门齿密集地排列在下颌骨的前端,呈圆弧状,与颊齿列斜交,而赣蹄兽的i3与颊齿列平行,i2稍斜。赣蹄兽下门齿的排列形式与早期偶蹄类Diacodexis pakistanensis相似,在亚洲始新世的Gobiohyus robuxtus和Lophiomeryx angarae也有类似的情况。赣蹄兽与Diacodexis、Gobiohyus和Wutuhyus等早期的偶蹄类的相似之处还在于下颌骨形态,较细长,较浅,下颌骨深度向前变浅,下臼齿向后增大,下前尖在舌面位置,下后尖在下原尖的后面,m1-2下次小尖在后缘上,m3下次小尖增大,并形成第三叶。但在p3-4形态上,赣蹄兽与这些早期偶蹄类不同,赣蹄兽明显比早期偶蹄类复杂,即臼齿化程度较高。赣蹄兽保留了像某些"踝节类"(如Litaletes)的p3-4,而它的下门齿排列却与早期偶蹄类相似。赣蹄兽下臼齿形态与早期偶蹄类具有相似性,因而不能归入"踝节目"已知科,很有可能代表与偶蹄类相关的一支古有蹄类。赣蹄兽的发现也为偶蹄类起源打开了新思路。

关键词：中国江西古新世类似偶蹄类的有蹄类

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《性别麻烦:女性主义与身份的颠覆》——后结构主义思潮下的激进性别政治思考

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妇女研究论丛 2010年第1期 91-96页

作者：宋素凤中山大学中文系广东广州510301

如果要列举上个20年最有影响力的女性主义理论家，巴特勒（judith Butler）应该会没有什么争议地名列榜单。她被誉为酷儿理论的开山祖师之一，而她的著作中影响最为深远、最知名的当属1990年出版的《性别麻烦：女性主义与身份的颠覆》... 详细信息

如果要列举上个20年最有影响力的女性主义理论家，巴特勒（judith Butler）应该会没有什么争议地名列榜单。她被誉为酷儿理论的开山祖师之一，而她的著作中影响最为深远、最知名的当属1990年出版的《性别麻烦：女性主义与身份的颠覆》（以下简称《性别麻烦》）。《性别麻烦》一书对主体、性、性别的思考不仅在女性主义、性别研究等领域引起很大的反响，推动了新的研究发展，它对身份政治所做的祛魅的努力，也对投身于妇女运动、同志运动等平权运动的人们有所启发。这本理论涉及甚广、文字艰涩的著作也难得地吸引了学院外广大读者的关注。

关键词：性别研究女性主义后结构主义政治思考激进思潮妇女运动酷儿理论

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