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hyperspectral imaging

Saabah B Mahbub, Martin Plöschner, Martin E Gosnell, Ayad G Anwer, Ewa M Goldys
Bioimaging using endogenous cell fluorescence, without any external biomarkers makes it possible to explore cells and tissues in their original native state, also in vivo. In order to be informative, this label-free method requires careful multispectral or hyperspectral recording of autofluorescence images followed by unsupervised extraction (unmixing) of biochemical signatures. The unmixing is difficult due to the scarcity of biochemically pure regions in cells and also because autofluorescence is weak compared with signals from labelled cells, typically leading to low signal to noise ratio...
November 17, 2017: Scientific Reports
Siti Salwa Md Noor, Kaleena Michael, Stephen Marshall, Jinchang Ren
In our preliminary study, the reflectance signatures obtained from hyperspectral imaging (HSI) of normal and abnormal corneal epithelium tissues of porcine show similar morphology with subtle differences. Here we present image enhancement algorithms that can be used to improve the interpretability of data into clinically relevant information to facilitate diagnostics. A total of 25 corneal epithelium images without the application of eye staining were used. Three image feature extraction approaches were applied for image classification: (i) image feature classification from histogram using a support vector machine with a Gaussian radial basis function (SVM-GRBF); (ii) physical image feature classification using deep-learning Convolutional Neural Networks (CNNs) only; and (iii) the combined classification of CNNs and SVM-Linear...
November 16, 2017: Sensors
Ralph Michael, Aufried Lenferink, Gijs F J M Vrensen, Ellen Gelpi, Rafael I Barraquer, Cees Otto
Neuritic plaques and neurofibrillary tangles are crucial morphological criteria for the definite diagnosis of Alzheimer's disease. We evaluated 12 unstained frontal cortex and hippocampus samples from 3 brain donors with Alzheimer's disease and 1 control with hyperspectral Raman microscopy on samples of 30 × 30 µm. Data matrices of 64 × 64 pixels were used to quantify different tissue components including proteins, lipids, water and beta-sheets for imaging at 0.47 µm spatial resolution. Hierarchical cluster analysis was performed to visualize regions with high Raman spectral similarities...
November 15, 2017: Scientific Reports
John K Delaney, Kathryn A Dooley, Roxanne Radpour, Ioanna Kakoulli
Macroscale multimodal chemical imaging combining hyperspectral diffuse reflectance (400-2500 nm), luminescence (400-1000 nm), and X-ray fluorescence (XRF, 2 to 25 keV) data, is uniquely equipped for noninvasive characterization of heterogeneous complex systems such as paintings. Here we present the first application of multimodal chemical imaging to analyze the production technology of an 1,800-year-old painting and one of the oldest surviving encaustic ("burned in") paintings in the world. Co-registration of the data cubes from these three hyperspectral imaging modalities enabled the comparison of reflectance, luminescence, and XRF spectra at each pixel in the image for the entire painting...
November 14, 2017: Scientific Reports
Faxian Cao, Zhijing Yang, Jinchang Ren, Mengying Jiang, Wing-Kuen Ling
As a new machine learning approach, the extreme learning machine (ELM) has received much attention due to its good performance. However, when directly applied to hyperspectral image (HSI) classification, the recognition rate is low. This is because ELM does not use spatial information, which is very important for HSI classification. In view of this, this paper proposes a new framework for the spectral-spatial classification of HSI by combining ELM with loopy belief propagation (LBP). The original ELM is linear, and the nonlinear ELMs (or Kernel ELMs) are an improvement of linear ELM (LELM)...
November 13, 2017: Sensors
Yan Zheng, Jiarui Bai, Jingna Xu, Xiayang Li, Yimin Zhang
Classification of plastics is important in the recycling industry. A plastic identification model in the near infrared spectroscopy wavelength range 1000-2500 nm is proposed for the characterization and sorting of waste plastics using acrylonitrile butadiene styrene (ABS), polystyrene (PS), polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), and polyvinyl chloride (PVC). The model is built by the feature wavelengths of standard samples applying the principle component analysis (PCA), and the accuracy, property and cross-validation of the model were analyzed...
November 9, 2017: Waste Management
Karel Žídek, Ondřej Denk, Jiří Hlubuček
We propose and demonstrate a spectrally-resolved photoluminescence imaging setup based on the so-called single pixel camera - a technique of compressive sensing, which enables imaging by using a single-pixel photodetector. The method relies on encoding an image by a series of random patterns. In our approach, the image encoding was maintained via laser speckle patterns generated by an excitation laser beam scattered on a diffusor. By using a spectrometer as the single-pixel detector we attained a realization of a spectrally-resolved photoluminescence camera with unmatched simplicity...
November 10, 2017: Scientific Reports
Xiaobin Wang, Chunjiang Zhao, Wenqian Huang, Qingyan Wang, Chen Liu, Guiyan Yang
BACKGROUND: The present study aimed to establish a method for the detection and quantification of azodicarbonamide (ADC) in flour using hyperspectral imaging technology. Hyperspectral images of pure flour, pure ADC, and flour-ADC mixtures with different concentrations of ADC were collected. F values of one-way ANOVA for all possible wavebands within the spectra of the flour and ADC were calculated, and the maximum value indicated that the two wavebands have more significant differences, that is, the optimal two wavebands...
November 10, 2017: Journal of the Science of Food and Agriculture
Berta Baca-Bocanegra, Julio Nogales-Bueno, José Miguel Hernández-Hierro, Francisco José Heredia
Extractable total phenolic content of American non-toasted oak (Quercus alba L.) shavings has been determined using near infrared hyperspectral imaging. A like-wine model solution was used for the simulated maceration procedure. Calibrations were performed by partial least squares regression (MPLS) using a number of spectral pre-treatments. The coefficient of determination of wood for extractable total phenolic content was 0.89, and the standard error of prediction was 6.3 mg g(-1). Thus, near infrared hyperspectral imaging arises as an attractive strategy for predicting extractable total phenolic content in the range of 0-65 mg g(-1), of great relevance from the point of view of quality assurance regarding wood used in the wine sector...
April 1, 2018: Food Chemistry
Kamel Mars, De Xing Lioe, Shoji Kawahito, Keita Yasutomi, Keiichiro Kagawa, Takahiro Yamada, Mamoru Hashimoto
Raman imaging eliminates the need for staining procedures, providing label-free imaging to study biological samples. Recent developments in stimulated Raman scattering (SRS) have achieved fast acquisition speed and hyperspectral imaging. However, there has been a problem of lack of detectors suitable for MHz modulation rate parallel detection, detecting multiple small SRS signals while eliminating extremely strong offset due to direct laser light. In this paper, we present a complementary metal-oxide semiconductor (CMOS) image sensor using high-speed lock-in pixels for stimulated Raman scattering that is capable of obtaining the difference of Stokes-on and Stokes-off signal at modulation frequency of 20 MHz in the pixel before reading out...
November 9, 2017: Sensors
Dominic Williams, Avril Britten, Susan McCallum, Hamlyn Jones, Matt Aitkenhead, Alison Karley, Ken Loades, Ankush Prashar, Julie Graham
Hyperspectral imaging is a technology that can be used to monitor plant responses to stress. Hyperspectral images have a full spectrum for each pixel in the image, 400-2500 nm in this case, giving detailed information about the spectral reflectance of the plant. Although this technology has been used in laboratory-based controlled lighting conditions for early detection of plant disease, the transfer of such technology to imaging plants in field conditions presents a number of challenges. These include problems caused by varying light levels and difficulties of separating the target plant from its background...
2017: Plant Methods
Quan Wan, Kerry J Abrams, Robert C Masters, Abdullah C S Talari, Ihtesham U Rehman, Frederik Claeyssens, Chris Holland, Cornelia Rodenburg
Nanostructures underpin the excellent properties of silk. Although the bulk nanocomposition of silks is well studied, direct evidence of the spatial variation of nanocrystalline (ordered) and amorphous (disordered) structures remains elusive. Here, secondary electron hyperspectral imaging can be exploited for direct imaging of hierarchical structures in carbon-based materials, which cannot be revealed by any other standard characterization methods. Through applying this technique to silks from domesticated (Bombyx mori) and wild (Antheraea mylitta) silkworms, a variety of previously unseen features are reported, highlighting the local interplay between ordered and disordered structures...
November 8, 2017: Advanced Materials
Owen G Rehrauer, Vu C Dinh, Bharat R Mankani, Gregery T Buzzard, Bradley J Lucier, Dor Ben-Amotz
The previously described optimized binary compressive detection (OB-CD) strategy enables fast hyperspectral Raman (and fluorescence) spectroscopic analysis of systems containing two or more chemical components. However, each OB-CD filter collects only a fraction of the scattered photons and the remainder of the photons are lost. Here, we present a refinement of OB-CD, the OB-CD2 strategy, in which all of the collected Raman photons are detected using a pair of complementary binary optical filters that direct photons of different colors to two photon counting detectors...
January 1, 2017: Applied Spectroscopy
Eberhard Grambow, Michael Dau, Amadeus Holmer, Vicky Lipp, Bernhard Frerich, Ernst Klar, Brigitte Vollmar, Peer Wolfgang Kämmerer
BACKGROUND/PURPOSE: Objective, reliable and easy monitoring of microvascular tissue perfusion is a goal that was achieved for many years with limited success. Therefore, a new non-invasive hyperspectral camera system (TIVITA™) was tested for this purpose in an in vivo animal model. METHODS: Evaluation of tissue oxygenation during ischemia and upon reperfusion was performed in left hind limb in a rat model (n=20). Ischemia was induced by clamping and dissection of the superficial femoral artery...
October 31, 2017: Microvascular Research
Karl St-Arnaud, Kelly Aubertin, Mathias Strupler, Wendy-Julie Madore, Andrée-Anne Grosset, Kevin Petrecca, Dominique Trudel, Frédéric Leblond
PURPOSE: Raman spectroscopy is a promising cancer detection technique for surgical guidance applications. It can provide quantitative information relating to global tissue properties associated with structural, metabolic, immunological and genetic biochemical phenomena in terms of molecular species including amino acids, lipids, proteins, and nucleic acid (DNA). To date in vivo Raman spectroscopy systems mostly included probes and biopsy needles typically limited to single-point tissue interrogation over a scale between 100 and 500 microns...
November 6, 2017: Medical Physics
Dagny Fleischman, Luke A Sweatlock, Hirotaka Murakami, Harry Atwater
The subwavelength mode volumes of plasmonic filters are well matched to the small size of state-of-the-art active pixels in CMOS image sensor arrays used in portable electronic devices. Typical plasmonic filters exhibit broad (> 100 nm) transmission bandwidths suitable for RBG or CMYK color filtering. Dramatically reducing the peak width of filter transmission spectra would allow for the realization of CMOS image sensors with multi- and hyperspectral imaging capabilities. We find that the design of 5 layer metal-insulator-metal-insulator-metal structures gives rise to multi-mode interference phenomena that suppress spurious transmission features and give rise to single transmission bands as narrow as 17 nm...
October 30, 2017: Optics Express
Guillaume Raffy, Robin Bofinger, Arnaud Tron, André Del Guerzo, Nathan D McClenaghan, Jean-Marc Vincent
An innovative photopatterning process is described that allows, in a single laser-promoted operation, the covalent attachment of a molecule on a surface (2D patterning - xy dimensions) and its photopolymerization to grow micro-/nanostructures with spatial control in a third z-dimension. The surface patterning process, based on nitrene reactivity, was harnessed using the highly fluorescent azide-substituted boron difluoride dipyrromethene (BODIPY) 1 that was prepared in a single synthetic step from the parent pentafluorophenyl BODIPY on reacting with NaN3...
November 9, 2017: Nanoscale
Yangyang Fan, Tao Wang, Zhengjun Qiu, Jiyu Peng, Chu Zhang, Yong He
Striped stem-borer (SSB) infestation is one of the most serious sources of damage to rice growth. A rapid and non-destructive method of early SSB detection is essential for rice-growth protection. In this study, hyperspectral imaging combined with chemometrics was used to detect early SSB infestation in rice and identify the degree of infestation (DI). Visible/near-infrared hyperspectral images (in the spectral range of 380 nm to 1030 nm) were taken of the healthy rice plants and infested rice plants by SSB for 2, 4, 6, 8 and 10 days...
October 27, 2017: Sensors
Lingyan Ran, Yanning Zhang, Wei Wei, Qilin Zhang
During recent years, convolutional neural network (CNN)-based methods have been widely applied to hyperspectral image (HSI) classification by mostly mining the spectral variabilities. However, the spatial consistency in HSI is rarely discussed except as an extra convolutional channel. Very recently, the development of pixel pair features (PPF) for HSI classification offers a new way of incorporating spatial information. In this paper, we first propose an improved PPF-style feature, the spatial pixel pair feature (SPPF), that better exploits both the spatial/contextual information and spectral information...
October 23, 2017: Sensors
Baowei Fei, Guolan Lu, Martin T Halicek, Xu Wang, Hongzheng Zhang, James V Little, Kelly R Magliocca, Mihir Patel, Christopher C Griffith, Mark W El-Deiry, Amy Y Chen
Hyperspectral imaging (HSI) is a relatively new modality in medicine and can have many potential applications. In this study, we developed label-free hyperspectral imaging for tumor margin assessment. HSI data, hypercube (x,y,λ), consists of a series of images of the same field of view that are acquired at different wavelengths. Every pixel in the hypercube has an optical spectrum. We collected surgical tissue specimens from 16 human subjects who underwent head and neck (H&N) cancer surgery. We acquired both HSI, autofluorescence images, and fluorescence images with 2-NBDG and proflavine from the specimens...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
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