Cancerous and normal human tissues investigated by near-infrared time-resolved and spectroscopic imaging techniques

2003 ◽  
Author(s):  
Mohammad Alrubaiee ◽  
Swapan K. Gayen ◽  
Jason A. Koutcher ◽  
Robert R. Alfano
Keyword(s):  
Near Infrared ◽  
Imaging Techniques ◽  
Spectroscopic Imaging ◽  
Human Tissues ◽  
Time Resolved ◽  
Normal Human

Vibrational Spectroscopic Microscopy: Raman, Near-Infrared and Mid-Infrared Imaging Techniques

1995 ◽  
Vol 1 (1) ◽  
pp. 35-46
Author(s):  
E. Neil Lewis ◽  
Ira W. Levin
Keyword(s):  
Focal Plane ◽  
Near Infrared ◽  
Imaging Techniques ◽  
Spectroscopic Imaging ◽  
Focal Plane Array ◽  
Acid Mixture ◽  
Infrared Focal Plane Array ◽  
Mid Infrared ◽  
Array Detectors ◽  
Infrared Spectral

New instrumental approaches for performing vibrational Raman, near-infrared and mid-infrared spectroscopic imaging microscopy are described. The instruments integrate imaging quality filters such as acousto-optic tunable filters (AOTFs), with visible charge-coupled device (CCD) and infrared focal-plane array detectors. These systems are used in conjunction with infinity-corrected, refractive microscopes for operation in the visible and near-infrared spectral regions and with Cassegrainian reflective optics for operation in the mid-infrared spectral interval. Chemically specific images at moderate spectral resolution (2 nm) and high spatial resolution (1 μm) can be collected rapidly and noninvasively. Image data are presented containing 128 × 128 pixels, although significantly larger format images can be collected in approximately the same time. The instruments can be readily configured for both absorption and reflectance spectroscopies. We present Raman emission images of polystyrene microspheres and a lipid/amino acid mixture and near-infrared images of onion epidermis and a hydrated phospholipid dispersion. Images generated from mid-infrared spectral data are presented for a KBr disk containing nonhomogeneous domains of lipid and for 50-μm slices of monkey cerebellum. These are the first results illustrating the use of infrared focal-plane array detectors as chemically specific spectroscopic imaging devices and demonstrating their application in biomolecular areas. Extensions and future applications of the various vibrational spectroscopic imaging techniques are discussed.

Non-Destructive Defect Detection of Apples by Spectroscopic and Imaging Technologies: A Review

2017 ◽  
Vol 60 (5) ◽  
pp. 1765-1790 ◽  
Author(s):  
Yuzhen Lu ◽  
Renfu Lu
Keyword(s):  
Near Infrared ◽  
Multispectral Imaging ◽  
Imaging Techniques ◽  
Mechanical Damage ◽  
Research Progress ◽  
Structured Illumination ◽  
Time Resolved ◽  
Wide Range ◽  
Detection Quality ◽  
Non Destructive

Abstract. Apples are susceptible to a wide range of defects that can occur in the orchard and during the post-harvest period. Detection of these defects by non-destructive sensing techniques is of great importance for the apple industry and has been an intensive research topic over the past two decades. This review presents an overview of common defects in apples, encompassing physiological disorders, mechanical damage, pathological disorders, and contamination. Presented and discussed in this review is research progress on the detection of defects in apples using various non-destructive spectroscopic and imaging techniques, including visible/near-infrared spectroscopy, fluorescence spectroscopy and imaging, monochromatic and color imaging, hyperspectral and multispectral imaging, x-ray imaging, magnetic resonance imaging, thermal imaging, time-resolved and spatially resolved spectroscopy, Raman spectroscopy, biospeckle imaging, and structured-illumination reflectance imaging. This review concludes with remarks on the prospects of these techniques and research needs in the future. Keywords: Apples, Defects, Imaging, Non-destructive detection, Quality, Safety, Spectroscopy.

scholarly journals Real-time observation of tetrapyrrole binding to an engineered bacterial phytochrome

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Yusaku Hontani ◽  
Mikhail Baloban ◽  
Francisco Velazquez Escobar ◽  
Swetta A. Jansen ◽  
Daria M. Shcherbakova ◽  
...  
Keyword(s):  
Real Time ◽  
Rational Design ◽  
Near Infrared ◽  
Fluorescent Proteins ◽  
Covalent Bond ◽  
Binding Pocket ◽  
Tissue Imaging ◽  
Covalent Attachment ◽  
Time Resolved

AbstractNear-infrared fluorescent proteins (NIR FPs) engineered from bacterial phytochromes are widely used for structural and functional deep-tissue imaging in vivo. To fluoresce, NIR FPs covalently bind a chromophore, such as biliverdin IXa tetrapyrrole. The efficiency of biliverdin binding directly affects the fluorescence properties, rendering understanding of its molecular mechanism of major importance. miRFP proteins constitute a family of bright monomeric NIR FPs that comprise a Per-ARNT-Sim (PAS) and cGMP-specific phosphodiesterases - Adenylyl cyclases - FhlA (GAF) domain. Here, we structurally analyze biliverdin binding to miRFPs in real time using time-resolved stimulated Raman spectroscopy and quantum mechanics/molecular mechanics (QM/MM) calculations. Biliverdin undergoes isomerization, localization to its binding pocket, and pyrrolenine nitrogen protonation in <1 min, followed by hydrogen bond rearrangement in ~2 min. The covalent attachment to a cysteine in the GAF domain was detected in 4.3 min and 19 min in miRFP670 and its C20A mutant, respectively. In miRFP670, a second C–S covalent bond formation to a cysteine in the PAS domain occurred in 14 min, providing a rigid tetrapyrrole structure with high brightness. Our findings provide insights for the rational design of NIR FPs and a novel method to assess cofactor binding to light-sensitive proteins.

scholarly journals Giant enhancement of THz-frequency optical nonlinearity by phonon polariton in ionic crystals

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yao Lu ◽  
Qi Zhang ◽  
Qiang Wu ◽  
Zhigang Chen ◽  
Xueming Liu ◽  
...  
Keyword(s):  
Near Infrared ◽  
Optical Nonlinearity ◽  
Ionic Crystals ◽  
Nonlinear Optical Susceptibility ◽  
Time Resolved ◽  
Light Coupling ◽  
Tremendous Progress ◽  
Fundamental Research ◽  
Ionic Contribution ◽  
Time Resolved Imaging

AbstractThe field of nonlinear optics has grown substantially in past decades, leading to tremendous progress in fundamental research and revolutionized applications. Traditionally, the optical nonlinearity for a light wave at frequencies beyond near-infrared is observed with very high peak intensity, as in most materials only the electronic nonlinearity dominates while ionic contribution is negligible. However, it was shown that the ionic contribution to nonlinearity can be much larger than the electronic one in microwave experiments. In the terahertz (THz) regime, phonon polariton may assist to substantially trigger the ionic nonlinearity of the crystals, so as to enhance even more the nonlinear optical susceptibility. Here, we experimentally demonstrate a giant second-order optical nonlinearity at THz frequency, orders of magnitude higher than that in the visible and microwave regimes. Different from previous work, the phonon-light coupling is achieved under a phase-matching setting, and the dynamic process of nonlinear THz generation is directly observed in a thin-film waveguide using a time-resolved imaging technique. Furthermore, a nonlinear modification to the Huang equations is proposed to explain the observed nonlinearity enhancement. This work brings about an effective approach to achieve high nonlinearity in ionic crystals, promising for applications in THz nonlinear technologies.

scholarly journals Ganoderma boninense Disease Detection by Near-Infrared Spectroscopy Classification: A Review

Sensors ◽  
2021 ◽  
Vol 21 (9) ◽  
pp. 3052
Author(s):  
Mas Ira Syafila Mohd Hilmi Tan ◽  
Mohd Faizal Jamlos ◽  
Ahmad Fairuz Omar ◽  
Fatimah Dzaharudin ◽  
Suramate Chalermwisutkul ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Early Detection ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Predictive Analytics ◽  
Detection System ◽  
Imaging Techniques ◽  
Ganoderma Boninense ◽  
Machine Learning Classification ◽  
Detection Techniques

Ganoderma boninense (G. boninense) infection reduces the productivity of oil palms and causes a serious threat to the palm oil industry. This catastrophic disease ultimately destroys the basal tissues of oil palm, causing the eventual death of the palm. Early detection of G. boninense is vital since there is no effective treatment to stop the continuing spread of the disease. This review describes past and future prospects of integrated research of near-infrared spectroscopy (NIRS), machine learning classification for predictive analytics and signal processing towards an early G. boninense detection system. This effort could reduce the cost of plantation management and avoid production losses. Remarkably, (i) spectroscopy techniques are more reliable than other detection techniques such as serological, molecular, biomarker-based sensor and imaging techniques in reactions with organic tissues, (ii) the NIR spectrum is more precise and sensitive to particular diseases, including G. boninense, compared to visible light and (iii) hand-held NIRS for in situ measurement is used to explore the efficacy of an early detection system in real time using ML classifier algorithms and a predictive analytics model. The non-destructive, environmentally friendly (no chemicals involved), mobile and sensitive leads the NIRS with ML and predictive analytics as a significant platform towards early detection of G. boninense in the future.

Sign in / Sign up

Export Citation Format

Share Document