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Quartel, John Conrad. "A study of near-field optical imaging using an infrared microscope." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313413.
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Bordy, Mathieu. "Synthèse et évaluation biologique de sondes fluorogènes pour la détection d’activités enzymatiques." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEN072.
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Cette thèse de doctorat traite de la conception et de l’évaluation de sondes fluorogènes pour la détection d’activités enzymatiques dans des contextes biologiques d’intérêt. L’élaboration de sondes fluorogéniques stables incorporant l’ELF-97 est une des thématiques de recherche activement poursuivie par notre équipe. Le développement avec succès de sondes peptidases et glycosidases a ouvert de nombreuses perspectives. Un premier chapitre sera dédié à la diversification de ces sondes, tout d’abord par la variation de substrats pour la détection de nouvelles glycosidases, puis par le développement d’un espaceur innovant dans un contexte particulier de sénescence cellulaire. Une sonde pour la détection de la β-galactosidase en milieu acide a notamment pu être synthétisée et testée. En parallèle, des travaux ont porté sur une nouvelle génération de sondes ciblant une famille d’enzymes à fort intérêt scientifique et sociétal : les β-lactamases. La synthèse et l’évaluation biologique préliminaire d’une première sonde modèle a démontré l’efficacité de cette nouvelle architecture moléculaire. Cette sonde a, par la suite, permis l’élaboration de premiers résultats d’imagerie dans le cadre d’une collaboration active avec une équipe de recherche japonaise. Enfin, un dernier volet sera consacré à un projet dont l’objectif n’est pas récent dans l’équipe : le développement d’alternatives à l’ELF-97 présentant une émission décalée vers le rouge ou le proche infrarouge. Ainsi, la synthèse de nouveaux fluorophores, leurs caractérisations physico-chimiques et des tests d’incorporation dans des dispositifs répondeurs ont notamment été réalisés. Plusieurs candidats se sont révélés à fort potentiel pour leur émission fortement décalée vers le rouge ou leur haute insolubilité. Ils pourraient permettre à terme l’adaptation de la technologie à une utilisation in vivo, but ultime de la technologie dans le cadre de l’imagerie moléculaireThis doctoral thesis deals with the design and evaluation of fluorogenic probes for the detection of enzymatic activities in biological contexts of interest.The development of stable fluorogenic probes incorporating ELF-97 is one of the research themes actively pursued by our team. The successful development of peptidases and glycosidases probes have opened many perspectives. A first chapter will be dedicated to the diversification of these probes, firstly by the variation of substrates for the detection of new glycosidases, then by the development of an innovative spacer in the context of cell senescence. In particular, a probe for the detection of β-galactosidase in acidic medium has been synthesized and tested.In parallel, work has focused on a new generation of probes targeting an enzyme family with strong scientific and societal interest : β-lactamases. The synthesis and the preliminary biological evaluation of a first model probe demonstrated the effectiveness of this new molecular architecture. This probe subsequently led to the development of first imaging results as part of an active collaboration with a Japanese research team.Finally, a last part will be devoted to a project whose objective is not recent in the team : the development of alternatives to the ELF-97 presenting a shifted emission towards the red or the near infrared. For this purpose, the synthesis of new fluorophores, their physicochemical characterizations and incorporation tests in responding devices have been carried out. Several candidates have proved to have high potential for two main reasons : strongly red-shifted emission or high insolubility. They could eventually allow the adaptation of the technology to an in vivo use, the ultimate goal of the technology in the context of molecular imaging
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Meyer, Yves. "Conception et développement de bras réactifs auto-immolables pour la synthèse de sondes pro-fluorescentes : applications à la détection de peptidases dans un contexte in-vivo." Thesis, Rouen, INSA, 2010. http://www.theses.fr/2010ISAM0018.
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L'objectif de cette thèse est la conception et le développement de bras espaceurs auto-immolables originaux situés entre le substrat peptidique et un fluorophore à phénol. Une première partie de ces travaux porte sur le développement de bras réactifs auto-immolables adaptés à la détection d'exopeptidases et à leur application pour la synthèse de sondes destinées à l'imagerie in-vivo de la caspase 3, une enzime impliquée dans le processus apoptotique. La seconde partie de ce travail relate les efforts effectués afin d'étendre l'utilisation des bras réactifs auto-immolables à la détection des endopeptidases, notamment les MMPs, une famille d'enzimes fortement impliquée dans la progression cancéreuseThe aim of this PhD work is the design and development of novel self-immolative species linking a peptide susbstrate to a phenolic fluorophore. A first part was dedicated to the development of self-immolative linkers for exopeptidases detection and their incorporation in caspase 3 probes to stain the apoptotic process. A second part was devoted to the extension of the strategy to endopeptidases, especially MMPs, an enzyme family mainly involved in cancer progression
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Damin, Craig Anthony. "Instrument Development and Application for Qualitative and Quantitative Sample Analyses Using Infrared and Raman Spectroscopies." Miami University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=miami1385774823.
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Lescure, Robin. "Développement d’azaBODIPYs fonctionnalisables pour la conception de sondes d’imagerie bimodale et d’agents théranostiques." Thesis, Bourgogne Franche-Comté, 2020. https://nuxeo.u-bourgogne.fr/nuxeo/site/esupversions/21e2771a-9c75-46d7-9377-50e8f2536c32.
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L’utilisation in vivo de l’imagerie optique est encore aujourd’hui principalement limitée par le manque de sondes capables d’émettre dans le proche infrarouge, où les tissus biologiques sont plus transparents à la lumière. Les travaux présentés dans ce manuscrit abordent l’optimisation et la valorisation d’une plateforme fluorescente hydrosoluble dont les propriétés optiques peuvent permettre une utilisation in vivo. Deux applications distinctes ont été envisagées pour cette plateforme WazaBY (Water-soluble azaBODIPY) : une utilisation comme sonde bimodale TEP (ou TEMP) et optique, et une utilisation en tant qu’agent théranostique. Lors du premier projet issu de ces travaux de thèse, nous avons pu développer une sonde bimodale TEMP/optique radiométallée par l’indium-111 et vectorisée par un anticorps (trastuzumab). Sur modèles murins porteurs de tumeurs xénogreffées, il a été possible de réaliser une imagerie bimodale optique/TEMP, témoignant d’une très nette accumulation au sein de la tumeur dès 24 heures après injection. La sonde a également été validée pour la réalisation de chirurgie assistée par fluorescence. Dans le cadre du second projet de cette thèse, une première génération d’agents théranostiques, porteurs de complexes d’or pour la thérapie, ont été synthétisées. L’objectif de ce projet a été de développer une nouvelle entité thérapeutique traçable in vitro et in vivo par imagerie optique. Les résultats préliminaires in vitro ont indiqué une activité antiproliférative des théranostiques sur lignées cellulaires cancéreuses (4T1, MDA MB 231, CT26 et SW480) voisine de celle de l’auranofine. Dans une seconde partie, nous nous sommes focalisés sur le développement de sondes théranostiques dites « intelligentes », pour lesquelles une modification des propriétés photophysiques est attendu lors du relargage éventuel du centre métallique. Deux molécules ont ainsi pu être synthétisées, chacune présentant un comportement de type on/offThe in vivo use of optical imaging is still limited by the lack of near infrared emitting probes. This thesis work focuses on the optimization and valorization of a water-soluble fluorescent platform whose optical properties enable an in vivo use. Two distinct applications were investigated for this WazaBY (Water-soluble azaBODIPY) platform: use as a PET (or SPECT) / optical bimodal probe, and as a theranostic agent. Concerning the first project, we were able to develop a targetted SPECT/optical bimodal probe, which was radiometallated with indium 111. Using xenografted murine models, we were able to show a clear accumulation of the probe in the tumor 24 hours after injection. Moreover, the probe was validated as a contrast agent for fluorescence guided surgery experiment. The second project of this thesis began by the synthesis of a first generation of gold based theranostic agents. The goal was to develop a new therapeutic complex, which can be tracked in vitro and in vivo thanks to optical imaging. In vitro preliminary results showed that the theranostics displayed a cytotoxicity comparable to auranofin on the tested cell lines (4T1, MDA MB 231, CT26 and SW480). A second part of this project focused on the develoment of « smart » probes for a theranostic use. Those probes are designed to undergo photophysical properties changes, when their metallic centre, responsible for the therapeutic role, is released. Two molecules were synthesized, both displaying an on/off behavior
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Minchin, Nigel Robert. "Near-infrared imaging polarimetry of bipolar nebulae." Thesis, University of Hertfordshire, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293286.
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Cheng, Hok Yan. "Near infrared fluorescence probes : towards applications in fluorescence guided surgery." Thesis, University of Hull, 2017. http://hydra.hull.ac.uk/resources/hull:16529.
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Surgery has been a popular method for the treatment of cancers, in particular solid tumours; but the surgical margins for cancerous tissues are often indistinct and in most cases, the poor identification of residual cancer tissues can result in re-excision. Therefore, near infrared (NIR) fluorescence-guided surgery (FGS) is being developed as a real time intra-operative imaging technique to assist surgeons by improving the accuracy and precision of the removal of tumours. However, current FDA approved fluorophores suffer from poor chemical stability, limited water-solubility, and lack selectivity toward neoplastic tissue, limiting their clinical application. These current challenges have led to the development of new and improved fluorophores capable of absorbing and emitting light at NIR wavelengths, negating autofluorescence and improving deeper light transmission. Throughout this project, a series of BODIPYs, aza-BODIPYs and bacteriochlorins were synthesised and developed for bioimaging applications. Despite many of them showing interesting fluorescence properties, the investigation suggested aza-BODIPYs were the most promising red / NIR fluorophores (λem 600-700 nm) due to their excellent photostability. Methods have been developed to incorporate functionalities suitable for bioconjugation. Different bioconjugation strategies have been explored to covalently conjugate the NIR fluorophores to a clinically relevant protein, peptide and antibody under mild conditions. The viability of aza-BODIPY conjugates against biological targets were investigated and a range of other novel targeted NIR fluorophores were successfully developed. In vitro fluorescence imaging was subsequently carried out to demonstrate the enhanced selectivity of the targeting NIR fluorophores toward overexpressed receptors on various cancer cells lines. This project has demonstrated the potential of aza-BODIPY in biological imaging and developed targeted NIR fluorophores. Further biological evaluation is progressing with the eventual aim of developing a pre-clinical model for NIR FGS in oncology.
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Packham, Christopher Charles. "Near infrared imaging and polarimetry of active galactic nuclei." Thesis, University of Hertfordshire, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338568.
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Servati, A. "Nanoparticles for simultaneous near-infrared and magnetic biomolecular imaging." Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1367959/.
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Nanoparticle probes can unlock the potential for multimodal biomedical imaging (in vivo and in vitro) with enhanced spatial resolution and penetration depth and targeted visualization of complex organisms. This thesis demonstrates synthesis and characterization of magnetic upconversion Gd2O3 nanoparticles that can serve as bimodal probes for optical imaging in near infrared (NIR) biomedical window, where minimal tissue auto uorescence is expected, as well as magnetic resonance imaging. More speci cally, Gd2O3:Yb3+,Tm3+ and Gd2O3:Yb3+,Er3+ nanoparticles are synthesized using urea-based homogeneous precipitation method (UHP) as well as Y2O3:Yb3+/Er3+ micro and nanoparticles using conventional combustion and thermal synthesis methods. The morphological and compositional properties of nanoparticles as well as their photonic and magnetic responses are systematically analyzed to understand the role of synthesis methods and initial synthesis materials including the concentrations of Tm and Er dopants and urea solution on the properties of the synthesized particles. The upconversion nanoparticles synthesized using UHP method are spherical and monodisperse with a size distribution in the range of 60 to 150 nm and controllable dopant concentration through manipulation of initial synthesis chemistry. When excited with 975 nm NIR radiation, Gd2O3:Yb3+,Tm3+ nanoparticles show a pure near infrared emission centered at around 810 nm (i.e., NIR-to-NIR upconversion) in NIR biological window with potential for high depth optical imaging while Er3+ doped particles emit light mainly in visible red centred at around 661 nm. The photoluminescence and transient optical decay measurements demonstrate distinctly di erent energy transfer mechanisms for Er and Tm doped samples. While these measurements signify a dominant role for Yb3+ dopants in strong upconversion emission of Tm3+ samples with a double exponential decay behaviour, they show less important role of Yb3+ in Er3+ samples with a single exponential decay. Systematic magnetic characterization demonstrate strong paramagnetic behaviour for the optically active upconversion nanoparticles, demonstrating their potential for bimodal optical and magnetic resonant imaging.
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Houston, Jessica Perea. "Near infrared optical lymphography for cancer diagnostics." Diss., Texas A&M University, 2005. http://hdl.handle.net/1969.1/4807.
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A new molecular imaging modality has been developed to detect and locate positive axillary and sentinel lymph nodes non-invasively in breast cancer patients undergoing lymphoscintigraphy. The modality is based on fluorescent photon detection to locate the presence of indocyanine green (ICG) in the lymph subsequent to peritumoral injection of ICG into the breast. The imaging system consists of a gain-modulated intensified charge-coupled device (ICCD) camera, which captures low-intensity, near-infrared, and frequency-modulated photons. A four-fold âÂÂoptical lymphographyâ study was conducted to (1) examine fluorescence depth penetration and ICCD system accuracy at clinically relevant depths, (2) compare image quality of the ICCD system vs. conventional gamma imaging, (3) measure ICG pharmacokinetics in vivo, and (4) develop a clinical protocol while examining pre-clinical factors such as the outcome of combining ICG with sulfur colloids used in lymphoscintigraphy. The frequency-domain ICCD system was found to precisely detect modulation amplitude, IAC, and phase, ø, at depths up to 9 cm and with IAC accuracy less than 20% and ø less than 2ú using an 80-mW laser incident on phantoms having ranging tissue optical properties. Significant differences in the mean depth of penetration owing to 0.62-ns lifetime and 100-MHz frequency increases were detected. An in vivo optical vs. nuclear image quality comparison demonstrated statistically similar (ñ=0.05) target-to-background ratios for optical (1.4+/-0.3) and nuclear (1.5+/-0.2). Alternatively, resulting image signal-to-noise ratios (SNR) from the ICCD system were greater than that achieved with a conventional gamma camera (pvalue<<0.01). Analysis of SNR versus contrast showed greater sensitivity of optical over nuclear imaging for subcutaneous tumors. In vivo and rapid detection of ICG in the blood-stream of nude mice was accomplished with a home-built avalanche photodiode dynamic fluorescence measurement system. Intensity data upon i.v. injection were regressed with a pharmacokinetic model describing the partitioning of ICG from the blood to the surrounding tissues. ICG blood-clearance was detected approximately 15 min after injection. Lastly, a human subject protocol was written, practiced, and federally approved for the application of optical lymphography. Furthermore, ICG was unaffected when mixed with sulfur colloids thus supporting the feasibility for combining fluorescence imaging with lymphoscintigraphy in breast cancer patients.
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Okoh, Okoh Adeyi. "The synthesis and evaluation of non-targeted near-infrared heptamethine molecular probes." Thesis, University of Central Lancashire, 2013. http://clok.uclan.ac.uk/9232/.
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Detecting and quantifying biomolecules is an important tool in biological research. Ideal dyes have to have a number of characteristics i.e. low toxicity and limited autofluorescence. The properties of near infrared dyes make these ideal for cell and tissue imaging. The work within this thesis focuses on the development of three families of NIR dyes (linear, rigid and substituted polymethine) and these are actively compared against the clinical standard Indocyanine Green (ICG) and its structural derivative New Indocyanine Green (IR-820). The ultimate aim being to identify dyes which can be used alongside the clinical standards. The compounds developed within this thesis are structurally based on the NIR heptamethine cyanine (Cy7) dyes. To expand, variations fall into three categories, linear, rigid and polymethine substituted, each being synthesised using either existing methodology or through the development of a novel cascade reaction. The photophysical properties of each dye have been evaluated experimentally, focusing on absorption and emission wavelengths, fluorescence quantum yields and Stokes shifts. It is noted that most dyes synthesised within this thesis, show comparable Stokes shift but increased fluorescence quantum yields when compared against ICG and IR-820. All dyes absorb and emit within the NIR region based on excitation at 785 nm. The growth inhibition characteristic is an important criterion which determines the practical use of the dyes in living cells. Most of the dyes which showed no growth inhibition were the dyes bearing the sulfonic acid group, suggesting the sulfonic acid limited cellular uptake as a result of decreased membrane permeability. Dyes possessing growth inhibitory characteristics all contain linear N-alkyl moieties. It is thus postulated that the increased lipophilicity of these molecules result in increased lipid distortion and subsequent toxicity.
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Schoedel, Rainer. "High Resolution Near-Infrared Imaging Observations of the Galactic Centre." Diss., lmu, 2004. http://nbn-resolving.de/urn:nbn:de:bvb:19-22565.
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Klohs, Jan [Verfasser]. "Near-infrared fluorescence imaging of inflammation in stroke / Jan Klohs." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2008. http://d-nb.info/1023328542/34.
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Close, Laird Miller. "High resolution near-infrared imaging with tip-tilt adaptive optics." Diss., The University of Arizona, 1995. http://hdl.handle.net/10150/187324.
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The development and design of the first operational tip-tilt Cassegrain secondary mirror are presented. This system, F ASTTRAC, samples image motion at up to 50 Hz by tracking either infrared (m(K)≤11) or visible (m(R)≤16) guide stars up to 30" and 90" away from the science target respectively. The Steward Observatory 2Jm or 1.5m telescope secondaries act as rapid tip-tilt mirrors to stabilize image motion (≤0.1" rms; ∼5 Hz -3 dB frequency) based on the motion of the guide star. F ASTTRAC obtains nearly diffraction-limited resolutions in seeing conditions where D/r₀<4 in agreement with theoretical expectations. FASTTRAC's unique ability to guide on infrared stars has allowed the first adaptively corrected images of the heavily extincted Galactic Center to be obtained. Over a hundred excellent (0.28"
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Wong, Gerald. "Snapshot hyperspectral imaging : near-infrared image replicating imaging spectrometer and achromatisation of Wollaston prisms." Thesis, Heriot-Watt University, 2012. http://hdl.handle.net/10399/2615.
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Conventional hyperspectral imaging (HSI) techniques are time-sequential and rely on temporal scanning to capture hyperspectral images. This temporal constraint can limit the application of HSI to static scenes and platforms, where transient and dynamic events are not expected during data capture. The Near-Infrared Image Replicating Imaging Spectrometer (N-IRIS) sensor described in this thesis enables snapshot HSI in the short-wave infrared (SWIR), without the requirement for scanning and operates without rejection in polarised light. It operates in eight wavebands from 1.1μm to 1.7μm with a 2.0° diagonal field-of-view. N-IRIS produces spectral images directly, without the need for prior topographic or image reconstruction. Additional benefits include compactness, robustness, static operation, lower processing overheads, higher signal-to-noise ratio and higher optical throughput with respect to other HSI snapshot sensors generally. This thesis covers the IRIS design process from theoretical concepts to quantitative modelling, culminating in the N-IRIS prototype designed for SWIR imaging. This effort formed the logical step in advancing from peer efforts, which focussed upon the visible wavelengths. After acceptance testing to verify optical parameters, empirical laboratory trials were carried out. This testing focussed on discriminating between common materials within a controlled environment as proof-of-concept. Significance tests were used to provide an initial test of N-IRIS capability in distinguishing materials with respect to using a conventional SWIR broadband sensor. Motivated by the design and assembly of a cost-effective visible IRIS, an innovative solution was developed for the problem of chromatic variation in the splitting angle (CVSA) of Wollaston prisms. CVSA introduces spectral blurring of images. Analytical theory is presented and is illustrated with an example N-IRIS application where a sixfold reduction in dispersion is achieved for wavelengths in the region 400nm to 1.7μm, although the principle is applicable from ultraviolet to thermal-IR wavelengths. Experimental proof of concept is demonstrated and the spectral smearing of an achromatised N-IRIS is shown to be reduced by an order of magnitude. These achromatised prisms can provide benefits to areas beyond hyperspectral imaging, such as microscopy, laser pulse control and spectrometry.
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Han, Xiao. "In vivo near-infrared fluorescence imaging of skin and cutaneous melanin." Thesis, Vancouver : University of British Columbia, 2006. http://hdl.handle.net/2429/77.
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In this Medical Physics M.Sc. project, a near-infrared (NIR) fluorescence imaging system was built for in-vivo diagnosis and evaluation of pigmented skin abnormalities and diseases. Light coming from a 785 nm diode laser is coupled into a ring light guide to uniformly illuminate the skin surface with a field-of-view (FOV) of 25 mm diameter. The diffuse reflectance and emitted fluorescence photons are collected by an NIR-sensitive CCD camera, with computer-controlled filter switch to select between reflectance mode and fluorescence mode. Both reflectance and fluorescence images of skin disorders were obtained with an exposure time of 2 seconds. The results show that cutaneous melanin in pigmented skin disorders emits higher NIR autofluorescence (AF) than surrounding normal tissue. This finding challanged the conventional concept that melanin is a non-fluorescence substance. The developed NIR autofluorescence imaging method also provided a new and direct way to characterize cutaneous melanin and can potentially be used for evaluation and diagnosis of pigmented skin diseases and skin cancers, such as melanoma.
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Fernando, Nilmi T. "Novel Near-Infrared Cyanine Dyes for Fluorescence Imaging in Biological Systems." Digital Archive @ GSU, 2011. http://digitalarchive.gsu.edu/chemistry_diss/57.
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Heptamethine cyanine dyes are attractive compounds for imaging purposes in biomedical applications because of their chemical and photophysical properties exhibited in the near-infrared region. A series of meso amino-substituted heptamethine cyanine dyes with indolenine, benz[e]indolenine and benz[c,d]indolenine heterocyclic moieties were synthesized and their spectral properties including fluorescence quntum yield were investigated in ethanol and ethanol/water mixture. Upon substitution with amines, the absorption maxima of the dyes shifted to the lower wavelength region (~600 nm), showed larger Stokes shifts and stronger fluorescence which can be attributed to an excited state intramolecular charge transfer (ICT). High quantum yields were observed for primary amine derivatives and lower quantum yields were observed for secondary amine derivatives. Fluorescence quantum yields are greater for dyes with 3H-indolenine terminal moieties than for dyes with benz[e]indolenine end groups. Benz[c,d]indolenine based heptamethine cyanine dyes exhibited the lowest quantum yield due to aggregation in solution. In general, the benz[e]indolenine hepatemethine cyanines showed high Stokes shifts compared to indolenine dyes. For the meso-chloro dyes, the absorption maxima for the dyes shifted bathochromically in the order of indolenine, benz[e]indolenine and benz[c,d]indolenine.
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Akin, Ryan E. "Minimally invasive assessment of lymphatic pumping pressure using near infrared imaging." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47536.
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Although the major functions of the lymphatic system are fairly well defined, its vasculature has yet to be well characterized in comparison to its blood vasculature counterpart. Recent advances in optical imaging techniques have allowed for more detailed and quantitative evaluations of lymph flow dynamics and mechanism. A rat tail is often used for investigations of lymph flow because of the simple geometry, superficial nature, and disease progression models of its collecting lymphatic vessels. In this study, a pressure cuff system was fabricated and coupled with an existing functional near infrared (NIR) imaging system to measure the overall pumping pressure of the lymphatic vessels of a rat tail. In addition to adapting the system for use on rodents, previous systems used for measuring lymphatic pumping pressure in humans were improved upon in several ways. The system defined here utilizes closed-loop feedback control of pressure application at smaller, more precise intervals. Using this device, a significant difference in lymphatic vessel pumping pressure was detected between a control case and a treatment case in which a vasoactive substance with a nitric oxide donor (GTNO ointment) was applied to the tail. Although it is known that nitric oxide plays a crucial physiologic role in propagation of flow through lymphatic vessels, this study has quantified its significant pharmacological reduction of pumping pressure for the first time.
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September, Danwille Jacqwin Franco. "Detection and quantification of spice adulteration by near infrared hyperspectral imaging." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6624.
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Thesis (MSc Food Sc)--University of Stellenbosch, 2011.ENGLISH ABSTRACT: Near infrared hyperspectral imaging (NIR HSI) in conjunction with multivariate image analysis was evaluated for the detection of millet and buckwheat flour in ground black pepper. Additionally, midinfrared (MIR) spectroscopy was used for the quantification of millet and buckwheat flour in ground black pepper. These techniques were applied as they allow non-destructive, invasive and rapid analysis. Black pepper and adulterant (either millet or buckwheat flour) mixtures were made in 5% (w/w) increments spanning the range 0-100% (w/w). The mixtures were transferred to eppendorf tube holders and imaged with a sisuChema short wave infrared (SWIR) pushbroom imaging system across the spectral range of 1000–2498 nm. Principal component analysis (PCA) was applied to pseudo-absorbance images for the removal of unwanted data (e.g. background, shading effects and bad pixels). PCA was subsequently applied to the ‘cleaned’ data. An adulterant concentration related gradient was observed in principal component one (PC1) and a difference between black pepper adulterated with buckwheat and millet was noted in PC4. Four absorption peaks (1461, 2241, 2303 and 2347 nm) were identified in the loading line plot of PC1 that are associated with protein and oil. The loading line plot of PC4 revealed absorption peaks at 1955, 1999, 2136 and 2303 nm, that are related to protein and oil. Partial least squares discriminant analysis (PLS-DA) was applied to NIR HSI images for discrimination between black pepper adulterated with varying amounts of adulterant (millet or buckwheat). The model created with millet adulterated black pepper samples had a classification accuracy of 77%; a classification accuracy of 70% was obtained for the buckwheat adulterated black pepper samples. An average spectrum was calculated for each sample in the NIR HSI images and the resultant spectra were used for the quantification of adulterant (millet or buckwheat) in ground black pepper. All samples were also analysed using an attenuated total reflectance (ATR) Fourier transform (FT) – infrared (IR) instrument and MIR spectra were collected between 576 and 3999 cm-1. PLS regression was employed. NIR based predictions (r2 = 0.99, RMSEP = 3.02% (w/w), PLS factor = 4) were more accurate than MIR based predictions (r2 = 0.56, RMSEP = 19.94% (w/w), PLS factors = 7). Preprocessed NIR spectra revealed adulterant specific absorption bands (1743, 2112 and 2167 nm) whereas preprocessed MIR spectra revealed a buckwheat specific signal at 1574 cm-1. NIR HSI has great promise for both the qualitative and quantitative analysis of powdered food products. Our study signals the beginning of incorporating hyperspectral imaging in the analysis of powdered food substances and results can be improved with advances in instrumental development and better sample preparation.
AFRIKAANSE OPSOMMING: Die gebruik van naby infrarooi hiperspektrale beelding (NIR HB) tesame met veelvoudige beeldanalise is ondersoek vir die opsporing van stysel-verwante produkte (giers en bokwiet) in gemaalde swart pepper. Middel-infrarooi (MIR) spektroskopie is addisioneel gebruik vir die kwantifisering van hierdie stysel-verwante produkte in swart pepper. Albei hierdie tegnieke is toegepas aangesien dit deurdringend van aard is en dit bied nie-destruktiewe sowel as spoedige analise. Swart pepper en vervalsingsmiddel (giers of bokwiet) mengsels is uitgevoer in 5% (m/m) inkremente tussen 0 en 100% (m/m). Eppendorfbuishouers is met die mengsels gevul en hiperspektrale beelde is verkry deur die gebruik van ‘n sisuChema SWIR (kortgolf infrarooi) kamera met ‘n spektrale reikwydte van 1000–2498 nm. Hoofkomponent-analise (HK) is toegepas op pseudo-absorbansie beelde vir die verwydering van ongewenste data (bv. agtergrond, skadu en dooie piksels). Hoofkomponent-analise is vervolgens toegepas op die ‘skoon’ data. Hoofkomponent (HK) een (HK1) het die aanwesigheid van ‘n vervalsingsmiddel konsentrasie verwante gradient getoon terwyl HK4 ‘n verskil getoon het tussen swart pepper vervals met giers en bokwiet. Vier absorpsiepieke (1461, 2241, 2303 en 2347 nm) was geïdentifiseer binne die HK lading stip van HK1 wat met proteïen en olie geassosieer kon word. Die HK lading stip van HK4 het absorpsipieke by 1955, 1999, 2136 en 2303 nm aangedui wat verband hou met proteïen en olie. Parsiële kleinste waarde diskriminant-analise (PKW-DA) is toegepas op die hiperspektrale beelde vir die moontlike onderskeiding tussen swart pepper vervals met verskeie hoeveelhede vervalsingsmiddel (giers of bokwiet). ‘n Klassifikasie koers van 77% is verkry vir die model ontwikkel met giers vervalsde swart pepper terwyl die model ontwikkel met bokwiet vervalsde swarte pepper ‘n klassifikasie koers van 70% bereik het. ‘n Gemiddelde spektrum is bereken vir elke monster in die hiperspektrale beelde en die resulterende spektra is gebruik vir die kwantifisering van vervalsingsmiddels (giers of bokwiet) in gemaalde swart pepper. ‘n ATR FT-IR instrument met spektrale reikwydte van 576-3999 cm-1 is additioneel gebruik vir die analise van alle monsters. Parsiële kleinste waarde regressie is gebruik vir kwantifikasie doeleindes. NIR gebasseerde voorspellings (r2 = 0.99, RMSEP = 3.02% (m/m), PLS faktore = 4) was meer akkuraat as die MIR gebasseerde voorspellings (r2 = 0.56, RMSEP = 19.94% (m/m), PLS faktore = 7). Vooraf behandelde NIR spektra het vervalsingsmiddel verwante absorpsiepieke (1743, 2112 en 2167 nm) aangetoon terwyl vooraf behandelde MIR spektra ‘n bokwiet verwante absorpsiepiek by 1574 cm-1 aangedui het. NIR HB toon goeie potensiaal vir beide kwalitatiewe en kwantitatiewe analise van gepoeierde voedsel produkte. Ons studie kan gesien word as die begin van die inkorporasie van hiperspektrale beelding in die analise van gepoeierde voedsel material en verbeterde resulte kan verkry word deur die vordering in instrumentasie ontwikkeling en verbeterde monstervoorbereiding.
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Zou, X. "Illumination invariant face recognition based on active near-infrared differential imaging." Thesis, University of Surrey, 2007. http://epubs.surrey.ac.uk/844079/.
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Changes in the illumination condition cause dramatic variation in face appearance and seriously affect the performance of face recognition systems. This problem is addressed in the thesis by introducing an approach based on active Near-Infrared differential imaging. Assuming a static scene, a linear response of the sensor to the scene radiation and no saturation, it is shown theoretically and empirically in this thesis that the active differential imaging technique yields a face image independent of the change in ambient illumination. By taking the difference of two face images, one captured with the active illumination on and one with it off, the resulting image contains the face illuminated only by the active illumination source. This technique is compared with several representative illumination invariant face recognition techniques on a database containing faces captured under different illuminations and at different time. The results in face identification and verification experiments demonstrate the significant advantage of this Near-Infrared differential imaging technique over the other techniques. This thesis also presents a multistage approach to automatic face localisation for the Near-Infrared face images. This multistage approach is a combination of a novel pupil detection approach based on edge following and chaincode representation, and an approach based on FloatBoost learning. Accurate face localisation results are achieved by the proposed multistage approach, and this leads to the excellent face recognition performance in fully automatic scenario. A subject appears at two different locations before and after the active illumination is turned on if he/she is moving. This causes motion artifact in the difference image from the active differential imaging system and degrades the performance of the face recognition system. The thesis presents an approach based on motion compensation to deal with this problem. It is shown from the experimental results that the proposed approach successfully removes the motion artifacts and improves the face recognition performance significantly.
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Puvanakrishnan, Priyaveena. "Near-infrared narrow-band imaging of gold/silica nanoshells in tumors." Thesis, [Austin, Tex. : University of Texas, 2009. http://hdl.handle.net/2152/ETD-UT-2009-05-43.
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Gragg, Jamie Loretta. "Synthesis of Near-Infrared Heptamethine Cyanine Dyes." Digital Archive @ GSU, 2010. http://digitalarchive.gsu.edu/chemistry_theses/28.
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Carbocyanine dyes are organic compounds containing chains of conjugated methine groups with electron-donating and electron-withdrawing substituents at the terminal heterocycles of the general formula [R1-(CH)n-R2]+X-. The synthetic methodology and optical properties of carbocyanines will be discussed. This thesis consists of two parts: (A) synthesis and optical properties of novel carbocyanine dyes substituted with various amines and the synthesis of unsymmetrical carbocyanine dyes containing monofunctional groups for bioconjugation. (B) synthesis of heptamethine carbocyanine dyes to be used for image-guided surgery. In part A, the synthesis of carbocyanine dyes functionalized with various amines and studies of their optical properties with respect to absorbance, fluorescence, quantum yield and extinction coefficient will be presented. These property studies will aid in designing efficient dyes for future biomedical applications. Part A will also include a one pot synthesis of unsymmetrical carbocyanine dyes functionalized with mono carboxylic acid chains, useful for biomolecule (i.e. proteins, amino acids, etc.) conjugation. Part B will describe the synthesis of novel carbocyanine dyes to be used for cancer image-guided surgery. Cancers are thus far incurable diseases, i.e. there are no drugs currently available to cure cancer; however, by designing a dye to visualize tumor cells will greatly increase the efficiency of cancer removal and hopefully increase the survival rate of cancer patients. The dyes reported in this thesis are superior to commercially available dyes used to visualize and identify various tumors invisible to the naked eye of surgeons with regards to biodistribution and clearance through kidney filtration.
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Lai, Puxiang. "PHOTOREFRACTIVE CRYSTAL-BASED ACOUSTO-OPTIC IMAGING IN THE NEAR-INFRARED AND ITS APPLICATIONS." Thesis, Boston University, 2010. https://hdl.handle.net/2144/1378.
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Acousto-optic (AO) sensing and imaging (AOI) is a dual-wave modality that
combines ultrasound with diffusive light to measure and/or image the optical properties of optically diffusive media, including biological tissues such as breast and brain. The light passing through a focused ultrasound beam undergoes a phase modulation at the ultrasound frequency that is detected using an adaptive interferometer scheme employing a GaAs photorefractive crystal (PRC). The PRC-based AO system operating at 1064 nm is described, along with the underlying theory, validating experiments, characterization, and optimization of this sensing and imaging apparatus. The spatial resolution of AO sensing, which is determined by spatial dimensions of the ultrasound beam or pulse, can be sub-millimeter for megahertz-frequency sound waves.A modified approach for quantifying the optical properties of diffuse media with AO sensing employs the ratio of AO signals generated at two different ultrasound focal pressures. The resulting “pressure contrast signal” (PCS), once calibrated for a particular set of pressure pulses, yields a direct measure of the spatially averaged optical transport attenuation coefficient within the interaction volume between light and sound. This is a significant improvement over current AO sensing methods since it produces a quantitative measure of the optical properties of optically diffuse media without a priori knowledge of the background illumination. It can also be used to generate images based on spatial variations in both optical scattering and absorption.
Finally, the AO sensing system is modified to monitor the irreversible optical changes associated with the tissue heating from high intensity focused ultrasound (HIFU) therapy, providing a powerful method for noninvasively sensing the onset and growth of thermal lesions in soft tissues. A single HIFU transducer is used to simultaneously generate tissue damage and pump the AO interaction. Experimental results performed in excised chicken breast demonstrate that AO sensing can identify the onset and growth of lesion formation in real time and, when used as feedback to guide exposure parameters, results in more predictable lesion formation.Bernard M. Gordon Center for Subsurface and Imaging Systems (CenSSIS) via the NSF ERC award number EEC-9986821.
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Gurfinkel, Mikhail. "Cancer diagnostics using dynamic near-infrared optical imaging and fluorescent contrast agents." Texas A&M University, 2005. http://hdl.handle.net/1969.1/3162.
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A new optical imaging modality has been developed for small animal in vivo imaging of near-infrared fluorescence resulting from fluorescent contrast agents specifically targeted to molecular markers of cancer. The imaging system is comprised of an intensified charge-coupled device (ICCD) for the detection of ultra-low levels of re-emitted fluorescence following the delivery of an expanded beam of excitation light. The design of the ICCD detection system allows for both continuous wave (CW) and frequency-domain modes of operation. Since the accurate acquisition of frequency-domain photon migration (FDPM) data is important for tomographic imaging, the imaging system was also validated using experimentally obtained FDPM measurements of homogenous turbid media and diffusion theory to obtain estimates of the optical properties characteristic of the media. The experiments demonstrated that the absorption and reduced scattering coefficients are determined least accurately when relative
rel
measurements of average light intensity IDC are employed either alone or in a
rel
combination with relative modulation amplitude data IAC and/or relative phase shift data
rel
. However, when FDPM measurements of are employed either alone or in
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combination with IAC data, the absorption and reduced scattering coefficients may be found accurate to within 15% and 11%, respectively, of the values obtained from standard single-pixel measurements; a result that suggests that FDPM data obtained from an ICCD detection system may in fact be useful in tomographic imaging. Furthermore, intensified-detection allows for sub-second exposure times, permitting the acquisition of dynamic fluorescence images immediately following administration of the contrast agent. Experimental results demonstrate that when coupled with a suitable pharmacokinetic model describing targeted dye distribution throughout the body, dynamic fluorescence imaging may be used to discriminate spontaneous canine adenocarcinoma from normal mammary tissue. A separate experiment demonstrates that pharmacokinetic analysis of dynamic fluorescence images enables one to estimate the rate constant governing Kaposi's sarcoma tumor uptake of an integrin-targeted dye and integrin receptor turnover rate. The rate constant for uptake was calculated to be 0.16-sec-1 while the turnover rate of the integrin receptor
was estimated to occur within 24-hours.
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Laborde, Antoine. "Detection of minor compounds in food powder using near infrared hyperspectral imaging." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASB017.
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L’imagerie hyperspectrale proche infrarouge (PIR) permet d’obtenir une carte spectrale d’un échantillon organique. La mesure d’un spectre pour chaque pixel de la caméra permet notamment la recherche de composés minoritaires dans les poudres agroalimentaires. Cependant, l’analyse spectrale PIR est limitée à une couche de profondeur donnée. De plus, la taille des particules associée à une résolution insuffisante des caméras PIR actuelles induisent un mélange des signaux spectraux dans les pixels de l’image. Ces deux problèmes sont une limitation pour l’analyse des composés minoritaires dans les poudres agroalimentaires.Nous proposons une méthode permettant de déterminer la profondeur de détection d’une cible composite placée dans un produit pulvérulent tel que la farine de blé. Basée sur une régression par projection sur les structures latentes, cette méthode permet d’appréhender l’atténuation du signal PIR lorsque la couche de poudre augmente, et ce malgré les problèmes inhérents à la détection en profondeur.De plus, deux stratégies de démélange de spectres sont proposées dans le but de détecter les pixels contenant des signatures de particules minoritaires. Le manque de valeur de référence utilisées en tant que données de validation des algorithmes ainsi que l’ambiguïté des spectres des composés pures à démélanger sont deux difficultés majeures. Une première stratégie consiste à modélisation la variabilité des spectres étudiés via l’Analyse en Composantes Principales afin de construire un algorithme de détection performant. La deuxième stratégie, basée sur la Multivariate Curve Resolution Alternating Least-Squares permet le démélange des signaux par pixels dans un cas plus complexeNear-infrared (NIR) hyperspectral imaging provides a spectral map for organic samples. Minor compounds in food powder can be looked for by analyzing the pixel spectra. However, the NIR spectral analysis is limited to a given depth. Besides, particles smaller than the pixel size induce a mixed spectral signature in the pixels. These two issues are an obstacle to the analysis of minor compounds in food powders.We propose a method to determine the detection depth of a composite target under a layer of powder such as wheat flour. It is based on the Partial Least Squares regression and provides an understanding of how the NIR signal is attenuated when the layer of powder despite the penetration depth issues.Two spectral unmixing strategies are proposed to detect pixel with minor compound NIR signatures. The lack of reference values to validate the model and the ambiguity of the spectral signature to unmix are two major difficulties. The first method models the spectral variability using Principal Component Analysis to design a performant detection algorithm. Then, for a more complex situation, the Multivariate Curve Resolution Alternating Least-Squares algorithm is used to unmix each pixel
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Merid, Yonathan. "Study of Cyanine Dye Binding to Amino Acids and Its Analytical Utility." Digital Archive @ GSU, 2010. http://digitalarchive.gsu.edu/chemistry_theses/27.
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Investigation of the NIR cyanine dye MHI-36 shows binding affinity to charged amino acids. This cyanine dye showed aggregation and dimer formation at higher dye concentration (2.0x10-3 M) induced by lysine. When dye concentration decreased to 1.0x10-4M no strong aggregate formation was viewed. Dye shows strong binding and selectivity properties towards charged amino acids lysine and arginine, compared to neutral leucine. It’s believed the positively charged presence was able to break and disrupt the conjugated π- π bonds at lower dye concentration. Computational work showed intramolecular aggregation of the phenyl groups on the dye. These aggregates are believed to create electron rich environment suitable for lysine interaction.
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Hillman, Elizabeth Marjorie Clare. "Experimental and theoretical investigations of near infrared tomographic imaging methods and clinical applications." Thesis, University College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268884.
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Norouzi, Neil. "Synthesis and application of novel near infrared cyanine dyes and optical imaging agents." Thesis, University of Edinburgh, 2014. http://hdl.handle.net/1842/10002.
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The use of fluorescent imaging probes for the real time detection of cellular malfunctions, such as enzyme over expression has shown promise. Fluorescent dyes with absorption and emission values below 600 nm are limited in their in vivo applications due to high background auto-fluorescence and low resolution images. Employing near infrared (NIR) fluorophores such as cyanine dyes can overcome this disadvantage. Cyanine dyes can be synthesised using solution or solid-phase techniques with the use of solution phase chemistry allowing for larger scale and higher yielding reactions. Utilising a selection of functional groups and varying polymethine chain lengths a cyanine dye library with tuneable absorption and emission wavelengths was synthesised. This thesis gives the first detailed examples of how modifications on heptamethine cyanine dyes alter their cellular uptake and cellular toxicity. Furthermore, a NIR fluorescent microsphere is reported as well as NIR functionalised microspheres with the ability to be tracked within cells. Additional lines of work involved the synthesis of a fluorescent sensor for the visualisation of bacteria. Aminopeptidases are present within the peptidoglycan cell wall of Gram negative bacteria and therefore can be targeted for real time detection of bacteria to aid in the detection of infectious diseases. A coumarin based probe is reported which detects aminopeptidase in gram negative bacteria in vitro.
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Carson, Kathryn Jane. "Contributions towards image reconstruction for functional imaging using time-resolved near-infrared measurements." Thesis, Keele University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240034.
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Pauff, Steven M. "Advancements in the Synthesis and Application of Near-Infrared Imaging Reagents: A Dissertation." eScholarship@UMMS, 2015. https://escholarship.umassmed.edu/gsbs_diss/751.
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Fluorescence-based imaging techniques provide a simple, highly sensitive method of studying live cells and whole organisms in real time. Without question, fluorophores such as GFP, fluorescein, and rhodamines have contributed vastly to our understanding of both cell biology and biochemistry. However, most of the fluorescent molecules currently utilized suffer from one major drawback, the use of visible light. Due to cellular autofluorescence and the absorbance of incident light by cellular components, fluorescence imaging with visible wavelength fluorophores often results in high background noise and thus a low signal-to-noise ratio. Fortunately, this situation can be ameliorated by altering the wavelength of light used during imaging. Near-infrared (NIR) light (650-900 nm) is poorly absorbed by cells; therefore, fluorophores excited by this light provide a high signal-to-noise ratio and low background in cellular systems. While these properties make NIR fluorophores ideal for cellular imaging, most currently available NIR molecules cannot be used in live cells. The first half of this thesis addresses the synthetic difficulties associated with preparing NIR fluorophores that can be used within living systems. Small molecule NIR fluorophores are inherently hydrophobic which makes them unsuitable for use in the aqueous environment of the cell. Water-solubility is imparted to these dyes through highly polar sulfonates, which subsequently prevents the dyes from entering the cell. The novel work presented here details vii synthetic routes to aid in the development of sulfonated NIR fluorophores, which can be delivered into live cells through the inclusion of an esterase-labile sulfonate protecting group. Application of these synthetic techniques should allow for the development of novel NIR fluorophores with intracellular applications. The second half of this thesis addresses the need for novel NIR imaging reagents. Although several classes of NIR scaffolds do exist, most NIR probes are derivatives of a single class, heptamethine indocyanines. The work described here increases this palette by displaying the ability of NIR oxazines to function as an imaging reagent in live cells and in vivo and as a molecular sensor of biologically-relevant environmental conditions. Combined, the work contained herein has the capacity to not only advance the current NIR toolkit, but to expand it so that fluorescence imaging can move out of the dark and into the NIR light.
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Langri, Dharminder Singh. "Monitoring Cerebral Functional Response using sCMOS-based High Density Near Infrared Spectroscopic Imaging." Wright State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=wright1558610822306817.
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Pauff, Steven M. "Advancements in the Synthesis and Application of Near-Infrared Imaging Reagents: A Dissertation." eScholarship@UMMS, 2001. http://escholarship.umassmed.edu/gsbs_diss/751.
Full textAbstract:
Fluorescence-based imaging techniques provide a simple, highly sensitive method of studying live cells and whole organisms in real time. Without question, fluorophores such as GFP, fluorescein, and rhodamines have contributed vastly to our understanding of both cell biology and biochemistry. However, most of the fluorescent molecules currently utilized suffer from one major drawback, the use of visible light. Due to cellular autofluorescence and the absorbance of incident light by cellular components, fluorescence imaging with visible wavelength fluorophores often results in high background noise and thus a low signal-to-noise ratio. Fortunately, this situation can be ameliorated by altering the wavelength of light used during imaging. Near-infrared (NIR) light (650-900 nm) is poorly absorbed by cells; therefore, fluorophores excited by this light provide a high signal-to-noise ratio and low background in cellular systems. While these properties make NIR fluorophores ideal for cellular imaging, most currently available NIR molecules cannot be used in live cells. The first half of this thesis addresses the synthetic difficulties associated with preparing NIR fluorophores that can be used within living systems. Small molecule NIR fluorophores are inherently hydrophobic which makes them unsuitable for use in the aqueous environment of the cell. Water-solubility is imparted to these dyes through highly polar sulfonates, which subsequently prevents the dyes from entering the cell. The novel work presented here details vii synthetic routes to aid in the development of sulfonated NIR fluorophores, which can be delivered into live cells through the inclusion of an esterase-labile sulfonate protecting group. Application of these synthetic techniques should allow for the development of novel NIR fluorophores with intracellular applications. The second half of this thesis addresses the need for novel NIR imaging reagents. Although several classes of NIR scaffolds do exist, most NIR probes are derivatives of a single class, heptamethine indocyanines. The work described here increases this palette by displaying the ability of NIR oxazines to function as an imaging reagent in live cells and in vivo and as a molecular sensor of biologically-relevant environmental conditions. Combined, the work contained herein has the capacity to not only advance the current NIR toolkit, but to expand it so that fluorescence imaging can move out of the dark and into the NIR light.
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Sumrain, Shadi. "DETECTION OF POLARIMETRIC SIGNATURES USING HIGH-EFFICIENCY POLARIMETRIC IMAGING TECHNIQUES." University of Akron / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=akron1125081616.
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Rodigas, Timothy John. "High-Contrast Near-Infrared Studies of Planetary Systems and their Circumstellar Environments." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/306772.
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Planets are thought to form in circumstellar disks, leaving behind planetesimals that collide to produce dusty debris disks. Characterizing the architectures of planetary systems, along with the structures and compositions of debris disks, can therefore help answer questions about how planets form. In this thesis, I present the results of five papers (three published, two in preparation) concerning the properties of extrasolar planetary systems and their circumstellar environments. Chapters 2 and 3 are studies of radial velocity (RV) exoplanetary systems. For years astronomers have been puzzled about the large number of RV-detected planets that have eccentric orbits (e>0.1). In Chapter 2 I show that this problem can partially be explained by showing that two circular-orbit planets can masquerade as a single planet on an eccentric orbit. I use this finding to predict that planets with mildly eccentric orbits are the most likely to have massive companions on wide orbits, potentially detectable by future direct imaging observations. Chapter 3 presents such a direct imaging study of the 14 Her planetary system. I significantly constrain the phase space of the putative candidate 14 Her c and demonstrate the power of direct imaging/RV overlap. Chapters 4 and 5 are high-contrast 2-4 μm imaging studies of the edge-on debris disks around HD 15115 and HD 32297. HD 15115's color is found to be gray, implying large grains 1-10 μm in size reside in stable orbits in the disk. HD 32297's disk color is red from 1-4 μm. Cometary material (carbon, silicates, and porous water ice) are a good match at 1-2 μm but not at L'. Tholins, organic material that is found in outer solar system bodies, or small silicates can explain the disk's red color but not the short wavelength data. Chapter 6 presents a dynamical study of dust grains in the presence of massive planets. I show that the width of a debris disk increases proportionally with the mass of its shepherding planet. I then make predictions for the masses and orbits of putative planets in five well-known disks. In Chapter 7, I summarize and discuss plans for future research in the exoplanet field.
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Nanyam, Yasasvy. "Hyperspectral Imaging for Nondestructive Measurement of Food Quality." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/theses/334.
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This thesis focuses on developing a nondestructive strategy for measuring the quality of food using hyperspectral imaging. The specific focus is to develop a classification methodology for detecting bruised/unbruised areas in hyperspectral images of fruits such as strawberries through the classification of pixels containing the edible portion of the fruit. A multiband segmentation algorithm is formulated to generate a mask for extracting the edible pixels from each band in a hypercube. A key feature of the segmentation algorithm is that it makes no prior assumptions for selecting the bands involved in the segmentation. Consequently, different bands may be selected for different hypercubes to accommodate the intra-hypercube variations. Gaussian univariate classifiers are implemented to classify the bruised-unbruised pixels in each band and it is shown that many band classifiers yield 100% classification accuracies. Furthermore, it is shown that the bands that contain the most useful discriminatory information for classifying bruised-unbruised pixels can be identified from the classification results. The strategy developed in this study will facilitate the design of fruit sorting systems using NIR cameras with selected bands.
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Concia, Massimo. "Fluorescence labeled PEI-based gene delivery systems for near infrared imaging in nude mice." Diss., lmu, 2010. http://nbn-resolving.de/urn:nbn:de:bvb:19-113095.
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Martinić, Ivana. "Novel perspectives in near-infrared optical imaging with lanthanide based molecules, macromolecules and nanomaterials." Thesis, Orléans, 2016. http://www.theses.fr/2016ORLE2033.
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Le domaine du proche infrarouge a une importance majeure pour l'imagerie optique en raison de la faible autofluorescence des systèmes biologiques et de la diffusion limitée de la lumière permettant l’amélioration du rapport signal-sur-bruit et une pénétration plus profonde dans les tissus. Les sondes fluorescentes proche-infrarouges les plus couramment utilisées à ce jour sont les fluorophores organiques ou les nanocristaux semi-conducteurs qui sont affectés par un certain nombre d’inconvénients. Plusieurs cations lanthanide possèdent des propriétés optiques uniques comme des bandes d'émissions étroites dont les longueurs d'ondes sont très peu sensibles à l’environnement, de grandes différences d’énergie entre longueurs d’onde d’excitation et d'émission et une forte résistance au photoblanchiment. Afin de bénéficier de la luminescence des lanthanides, les faibles absorbances des cations lanthanides libres doivent être compensées par l'utilisation de groupes chromophores appropriés fonctionnant comme sensibilisateurs. On parle d’effet d’"antenne". Nous présentons dans ce travail plusieurs familles de sondes à base de lanthanides (i) de petites molécules, plus spécifiquement des complexes monométalliques constitués par la coordination de Ln³⁺ par un ligand de type TTHA-anthraquinone et des métallacrowns polymétalliques Ln³⁺/Zn²⁺ auto-assemblés; (ii) de nouveaux nanomatériaux basés sur des billes de polystyrène possédant deux types de chargements différents, à savoir (i) un complexe bimétallique d-f Cr³⁺-Ln³⁺ ainsi que (ii) des antennes dérivées d’hydroxyanthraquinone et des cations lanthanide libres; (iii) des macromolécules de type dendrimère polyamidoamine de génération 3 fonctionnalisés avec sensibilisateurs aza-BODIPY en leurs périphéries et qui encapsulent des lanthanide luminescents. Les propriétés photophysiques, la cytotoxicité et l'incorporation cellulaire ont été décrites et discutées pour chacun des types de sondes. En outre, ces sondes ont été testées en imagerie in vitro visible et/ou proche-infrarouge par des expériences de microscopie confocale et d’épifluorescence. L’ensemble des sondes décrites dans ce travail, en raison de leurs propriétés avantageuses et nouvelles, constituent des avancées majeures pour le développement de nouvelles générations d'agents d'imagerie optiqueThe near-infrared (NIR) region has a significant importance for optical imaging due to the minimal autofluorescence and reduced light scattering thus allowing for improved signal-to-noise ratio and deeper penetration through tissues. Nowadays, the most commonly used NIR-emitting fluorescent probes rely mainly on organic fluorophores or quantum dots and exhibit drawbacks. Several lanthanide(III) ions (Ln³⁺) possess unique optical properties e.g. sharp emission bands the wavelengths of which have minimal sensitivity to the microenvironment, large differences between excitation and emission wavelengths and strong resistance toward photobleaching. In order to obtain the luminescence of lanthanides, the low absorbances of the free Ln³⁺ have to be overcome by the use of appropriate chromophoric groups functioning as a sensitizing “antenna”. We present here several families of Ln³⁺-based probes: (i) small molecules, in particular monometallic complexes constituted by the TTHA-anthraquinone moiety and Ln³⁺, and polymetallic self-assembled Ln³⁺/Zn²⁺ metallacrowns; (ii) novel nanomaterials based on polystyrene beads with two different loadings, i.e. d-f bimetallic Cr³⁺- Ln³⁺+ complex and hydroxyanthraquinone antennae and Ln³⁺ ; (iii) macromolecular generation-3 polyamidoamine dendrimers functionalized with aza-BODIPY sensitizers at their periphery and encapsulating the luminescent Ln³⁺. The photophysical properties, cytotoxicity and cellular uptake were reported and discussed for each of the presented types of Ln³⁺-based probes. Moreover, these probes were successfully tested for visible and/or NIR in vitro imaging by confocal or epifluorescence microscopy experiments. Finally, the reported Ln³⁺-based probes, due to the number of advantageous properties, represent significant breakthroughs toward the developments of new generations of optical imaging agents
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Makein, Lisa Jane. "Correlation of Near-infrared chemical imaging of pharmaceutical dosage forms with their dissolution performance." Thesis, University College London (University of London), 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.498097.
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Jones, David Alexander. "Near-infrared spectral imaging as a detection technique for organic materials in porous media." Diss., The University of Arizona, 2004. http://hdl.handle.net/10150/280479.
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Imaging spectroscopy combines the spatial discrimination of imaging techniques with the chemical information of spectroscopy to form a powerful tool for the study of chemically heterogeneous systems. This work describes the in situ qualitative and quantitative analysis of contaminant transport flow cells and of high-performance thin-layer chromatography (HPTLC) plates by near-infrared imaging spectroscopy. A solid-state, near-infrared imaging spectrometer was constructed for these studies. The spectrometer utilized an imaging quality acousto-optic tunable filter for wavelength selection over the 1.3-2.3 μ range and a cryogenically cooled, 240 x 324 pixel platinum silicide camera for detection. Samples were analyzed by either diffuse reflectance or diffuse transmittance using a 250 W quartz-tungsten-halogen lamp for sample illumination. The first series of investigations focused on the analysis of laboratory-scale flow cells, which are used to study the transport of non-aqueous phase liquid (NAPL) contaminants in the soil and groundwater. Current detection systems used for determining NAPL distribution are incapable of distinguishing between chemical components in NAPL mixtures, limiting flow cell experiments to the study of simple systems. This research utilized the near-infrared imaging spectrometer and multivariate calibration techniques to quantitatively determine the concentrations of individual constituents in binary NAPL mixtures within vadose zone and aquifer models. The vadose zone calibration data was used to determine the spatial distribution of each NAPL constituent in situ during a dynamic, multi-component flow cell experiment that modeled the remediation of NAPL contaminated soil. This technique, the first to quantitatively determine the in situ distribution of the individual NAPL phase constituents, represents the state of the art in detection for contaminant transport flow cells. The second series of investigations focused on analysis of samples on HPTLC plates. Conventional systems require visualization techniques to detect compounds lacking a chromophore or fluorophore. This research utilized the near-infrared imaging spectrometer as a non-destructive detection technique to provide qualitative and quantitative information for caffeine samples on HPTLC plates. Both diffuse reflectance and diffuse transmittance measurements provided detection limits of several micrograms. The caffeine spectrum was clearly distinguishable down to 25 μg using a diffuse reflectance geometry with a mirrored backing applied to the HPTLC plate.
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Muroga, Shun. "Near-infrared Hyperspectral Imaging of Polymeric Products for Nondestructive Quality Assessment in Polymer Processing." Kyoto University, 2019. http://hdl.handle.net/2433/242473.
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Watson, Amy Dawn. "Binding studies of near infrared cyanine dyes with human serum albumin anf poly-l-lysine using optical spectroscopy methods." unrestricted, 2006. http://etd.gsu.edu/theses/available/etd-01042008-154159/.
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Thesis (Ph. D.)--Georgia State University, 2006.Title from file title page. Gabor Patonay, committee chair; Zhen Huang, Alfons Baumstark, committee members. Electronic text (236 p. : ill. (some col.)) : digital, PDF file. Description based on contents viewed Jan. 28, 2008. Includes bibliographical references.
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Hall, David Jonathan. "The development of a near infrared time resolved imaging system and the assessment of the methodology for breast imaging." Thesis, University College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243779.
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Gao, Du Yang. "Engineering of protein-based multifunctional nanoparticles with near-infrared absorption as photoacoustic contrast agents for biological applications." Thesis, University of Macau, 2018. http://umaclib3.umac.mo/record=b3953810.
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Martí, Aluja Idoia. "Analysis of polymerisation / aggregation processes by nir chemical imaging and ftir spectroscopy." Doctoral thesis, Universitat Rovira i Virgili, 2013. http://hdl.handle.net/10803/125668.
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El principal objectiu d’aquesta tesi és desenvolupar mètodes analítics basats en la combinació entre l’espectroscòpia d’infraroig i tècniques quimiomètriques per analitzar in situ un procés de polimerització i l’agregació de la insulina. El procés de polimerització es va monitoritzar mitjançant la tècnica de near-infraredchemicalimaging (NIR-CI). L’anàlisi quimiomètric de les dades obtingudes ha permès evidenciar la presència d’un equilibri tautomèric d’un dels reactius. El segon procés estudiat ha estat l’agregació de la insulina, establint diverses metodologies basades en l’espectroscòpia d’infraroig (IR). Aquestes metodologies han permès, per una banda, avaluar l’efecte de fàrmacs antiretrovirals en el procés; i per altra banda, la influència de les tres variables bioquímiques més importants (temperatura, pH i força iònica) en el procés.The overall objective of this thesis is to develop analytical methods based on infrared spectroscopy and chemometric techniques to analyse two different processes that involve a state change from a liquid to a solid. The first studied process is a polymerisation process and it was followed by near-infrared chemical imaging (NIR-CI). The chemometric treatment of the images acquired allowed evidencing a tautomer’s equilibrium of one of the reagents. The second studied process was insulin aggregation. Aggregation process was monitored infrared spectroscopy (IR), and different methods were established which allowed on the one hand the assessment of the effect of antiretroviral drugs on the process; and on the other hand, the influence of biochemical variables on the process.
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Zalavadia, Ajaykumar. "A Broadly Tunable Surface Plasmon-Coupled Wavelength Filter for Visible and Near Infrared Hyperspectral Imaging." Cleveland State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=csu1522253688346498.
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Mushonga, Paul. "Fabrication of type-I indium-based near-infrared emitting quantum dots for biological imaging applications." University of the Western Cape, 2013. http://hdl.handle.net/11394/8271.
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Doctor Scientiae - DScSemiconductor nanocrystals or quantum dots (QDs) are fluorescent nanometer-sized particles which have physical dimensions that are smaller than the excitonic Bohr radius, large surface area-to-volume ratios, broad absorption spectra and very large molar extinction coefficients. Biomedical applications of QDs are mainly based on II-VI QDs containing cadmium, such as CdSe/ZnS. These cadmium-based systems are associated with high toxicity due to cadmium. As a result, potential replacements of cadmium-based QDs in biological applications are needed. In this study, InP/ZnSe QDs were synthesized for the first time using a one-pot hot injection method. Furthermore, a growth-doping method was used for silver, cobalt and iron incorporation into the InP core. Water compatibility was achieved through ligand exchange with 3- mercaptopropionic acid. In vitro cytotoxicity and imaging/internalization of the as-prepared MP A-InP/ZnSe and MP A-capped CdTe/ZnS QDs were evaluated. InP/ZnSe QDs were successfully synthesized with ZnSe shell causing a 1.4 times reduction in trap-related emission.
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Stein-Merlob, Ashley F. "Nanoparticle-Enhanced Near Infrared Fluorescence Imaging of Atheroma Detects Thrombosis-Prone Plaques Prior to Rupture." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:15821600.
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Introduction: Acute coronary syndromes - including unstable angina, acute myocardial infarction and sudden death - are primarily due to sudden luminal thrombosis from disruption of an atherosclerotic plaque. It has been established that inflammation plays an important role in atherogenesis and the destabilization of plaques. However, the role of inflammation in catalyzing plaque rupture is incompletely understood. Here, we experimentally investigated the in vivo spatial distribution of a novel atheroma cell targeted near-infrared fluorescence (NIRF) imaging agent, CLIO-CyAm7, prior to triggered plaque rupture, using intravascular molecular imaging. We hypothesized that CLIO-CyAm7 would illuminate macrophages on in vivo intravascular NIRF imaging and preferentially localize to atheroma that develop plaque thrombosis under triggering conditions.
Methods: Atherosclerosis was induced in rabbits (n=28) using a 12-week hyperlipidemic diet with alternating 1% high cholesterol and normal chow with concomitant aortic balloon injury at 2 weeks. Rabbits were injected with 2.5mg/kg of CLIO-CyAm7 24 hours prior to in vivo imaging. In vivo NIRF and intravascular ultrasound (IVUS) imaging were used to assess baseline structural and inflammation characteristics of atheroma. Control rabbits (n=6) were sacrificed prior to triggering. Pharmacological triggering was performed using Russell’s Viper Venom (0.15mg/kg IP) and histamine (0.02mg/kg IV) injections twice over 48-hours. IVUS imaging was repeated prior to sacrifice to identify luminal thrombi in vivo. NIRF imaging was quantified using target-to-background ratio (TBR), the ratio between an area of atheroma compared to normal, uninjured aorta. A subset of rabbits (n=7) was injected with Evans Blue (6mL 0.5% IV) 30 minutes prior to sacrifice to identify permeability of the endothelium. After sacrifice, ex vivo imaging, fluorescence microscopy (FM), RAM-11 immunofluorescence (IF) of macrophages, alpha-smooth muscle actin IF for smooth muscle cells, CD31 IF for endothelial cells, and Carstairs’ staining for fibrin and collagen, were performed systematically along the length of the aorta at 1.5cm increments. Data is presented as mean±SD.
Results: On microscopy, CLIO-CyAm7 localized primarily at the intimal-luminal border of atheroma, with some penetration into the media and adventitia. There was significantly higher CLIO-CyAm7 accumulation in areas of atheroma compared to control segments of the aorta (1.73±1.9% vs. 0.13±0.28%, p<0.0001). On IF, CLIO-CyAm7 signal correlated with subsets of macrophages, endothelial cells and smooth muscle cells in atheroma with minimal CLIO-CyAm7 evident in normal arteries. Evans blue showed increased endothelial permeability in regions of increased subendothelial CLIO-CyAm7 accumulation. CD31+ endothelial cells in the neovessels at the intima-media border indicated delivery of CLIO-CyAm7 via vaso vasorum. In vivo, CLIO-CyAm7+ plaques were detectable via intravascular NIRF imaging. Areas of atherosclerosis, determined by IVUS, showed significantly higher NIRF peak TBR than normal segments of the aorta (2.86±1.82 vs. 1.55±0.65, p=0.001). In vivo IVUS imaging and Carstairs’ staining for fibrin identified plaque thrombosis in 10 of 15 rabbits undergoing the triggered protocol (67%). Notably, plaques with luminal thrombosis showed significantly higher CLIO- CyAm7 accumulation compared to undisrupted atheroma (2.1±1.7% vs. 1.5±1.9%, p=0.0446), indicating that atheroma cell phagocytic capacity may underlie plaque rupture.
Conclusion: CLIO-CyAm7 is a novel NIRF molecular imaging agent that identifies a subset of phagocytically active cells that are increased in atheroma prone to plaque thrombosis. Intravascular 2D NIRF imaging provides a promising future translational tool for high-resolution imaging of biologically high-risk plaques.
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PALUKURU, UDAY P. "Development of Near Infrared Spectral Analysis for Native, Engineered and Degraded Cartilage." Diss., Temple University Libraries, 2014. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/270245.
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BioengineeringPh.D.
Articular cartilage helps in the motion of the diarthroidal joints by providing a near frictionless load bearing surface. Identification of changes in articular cartilage chemical and structural properties that arise from degeneration and suboptimal tissue repair have been the target of many studies. Current methods that evaluate these changes frequently involve destructive specimen preparation. Thus there is a need to develop a method to accurately evaluate changes in cartilage during disease or repair processes. Fourier transform infrared (FTIR) spectroscopy in the mid-infrared (MIR) spectral range is based on molecular vibrations and has been used to study the chemical and structural properties of biological tissues, including cartilage. However, this technique generally requires extensive sample preparation and modification of the intact tissue. An alternative approach is to use near-infrared spectroscopy (NIRS) which does not require sample preparation due to higher depth of penetration. This doctoral dissertation focuses on identification of NIR spectral features to evaluate the major components of cartilage. These NIR spectral features are then used to evaluate compositional changes in engineered and degraded cartilage, and the results validated with histological, biochemical, mechanical and MIR analysis of the same tissue. Together, these studies lay the groundwork for clinical and in situ applications of NIRS.
Temple University--Theses
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Zhang, Lin. "PATTERN RECOGNITION METHODS FOR THE ANALYSIS OF INFRARED IMAGING DATA AND MULTIVARIATE CALIBRATION STANDARDIZATION FOR NEAR-INFARED SPECTROSCOPY." Ohio : Ohio University, 2002. http://www.ohiolink.edu/etd/view.cgi?ohiou1013445546.
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Riseby, Emil, and Alexander Svensson. "Multispectral Imaging for Surveillance Applications." Thesis, Linköpings universitet, Medie- och Informationsteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-115731.
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Silicon based sensors is a commonly used technology in digital cameras today. That has made such cameras relatively cheap and widely used. Unfortunately they are constructed to capture and represent image quality for humans. Several image applications work better without the restrictions of the visible spectrum. Human visual restrictions are often indirectly put on technology by using images showing only visible light. Thinking outside the box in this case is seeing beyond the visible spectrum.