The Experts below are selected from a list of 11922 Experts worldwide ranked by ideXlab platform
Zubin Jacob - One of the best experts on this subject based on the ideXlab platform.
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axial super resolution Evanescent Wave tomography
Optics Letters, 2016Co-Authors: Sarang Pendharker, Swapnali Shende, Ward D Newman, Stephen Ogg, Neda Nazemifard, Zubin JacobAbstract:Optical tomographic reconstruction of a three-dimensional (3D) nanoscale specimen is hindered by the axial diffraction limit, which is 2–3 times worse than the focal plane resolution. We propose and experimentally demonstrate an axial super-resolution Evanescent Wave tomography method that enables the use of regular Evanescent Wave microscopes like the total internal reflection fluorescence microscope beyond surface imaging and achieve a tomographic reconstruction with axial super-resolution. Our proposed method based on Fourier reconstruction achieves axial super-resolution by extracting information from multiple sets of 3D fluorescence images when the sample is illuminated by an Evanescent Wave. We propose a procedure to extract super-resolution features from the incremental penetration of an Evanescent Wave and support our theory by one-dimensional (along the optical axis) and 3D simulations. We validate our claims by experimentally demonstrating tomographic reconstruction of microtubules in HeLa cells with an axial resolution of ∼130 nm. Our method does not require any additional optical components or sample preparation. The proposed method can be combined with focal plane super-resolution techniques like stochastic optical reconstruction microscopy and can also be adapted for THz and microWave near-field tomography.
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axial super resolution Evanescent Wave tomography
arXiv: Optics, 2016Co-Authors: Sarang Pendharker, Swapnali Shende, Ward D Newman, Stephen Ogg, Neda Nazemifard, Zubin JacobAbstract:Optical tomographic reconstruction of a 3D nanoscale specimen is hindered by the axial diffraction limit, which is 2-3 times worse than the focal plane resolution. We propose and experimentally demonstrate an axial super-resolution Evanescent Wave tomography (AxSET) method that enables the use of regular Evanescent Wave microscopes like Total Internal Reflection Fluorescence Microscope (TIRF) beyond surface imaging, and achieve tomographic reconstruction with axial super-resolution. Our proposed method based on Fourier reconstruction achieves axial super-resolution by extracting information from multiple sets of three-dimensional fluorescence images when the sample is illuminated by an Evanescent Wave. We propose a procedure to extract super-resolution features from the incremental penetration of an Evanescent Wave and support our theory by 1D (along the optical axis) and 3D simulations. We validate our claims by experimentally demonstrating tomographic reconstruction of microtubules in HeLa cells with an axial resolution of $\sim$130 nm. Our method does not require any additional optical components or sample preparation. The proposed method can be combined with focal plane super-resolution techniques like STORM and can also be adapted for THz and microWave near-field tomography.
Shinya Nagamatsu - One of the best experts on this subject based on the ideXlab platform.
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imaging exocytosis of single insulin secretory granules with Evanescent Wave microscopy distinct behavior of granule motion in biphasic insulin release
Journal of Biological Chemistry, 2002Co-Authors: Mica Oharaimaizumi, Yoko Nakamichi, Toshiaki Tanaka, Hitoshi Ishida, Shinya NagamatsuAbstract:To study insulin exocytosis by monitoring the single insulin secretory granule motion, Evanescent Wave microscopy was used to quantitatively analyze the final stage of insulin exocytosis with biphasic release. Green fluorescent protein-tagged insulin transfected in MIN6 beta cells was packed in insulin secretory granules, which appeared to preferentially dock to the plasma membrane. Upon fusion evoked by secretagogues, Evanescent Wave microscopy revealed that fluorescence of green fluorescent protein-tagged insulin brightened, spread (within 300 ms), and then vanished. Under KCl stimulation, which represents the 1st phase of release, the successive fusion events were seen mostly from previously docked granules for the first minute, followed by the recruitment of new granules to the plasmalemmal docking sites. Stimulation with glucose, in contrast, caused the fusion events from previously docked granules for the first 120 s, thereafter a continuous fusion (2nd phase of release) was observed over 10 min mostly from newly recruited granules that progressively accumulated on the plasma membrane. Thus, our data revealed the distinct behavior of the insulin granule motion during the 1st and 2nd phase of release.
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imaging exocytosis of single insulin secretory granules with Evanescent Wave microscopy distinct behavior of granule motion in biphasic insulin release
Journal of Biological Chemistry, 2002Co-Authors: Mica Oharaimaizumi, Yoko Nakamichi, Toshiaki Tanaka, Hitoshi Ishida, Shinya NagamatsuAbstract:To study insulin exocytosis by monitoring the single insulin secretory granule motion, Evanescent Wave microscopy was used to quantitatively analyze the final stage of insulin exocytosis with biphasic release. Green fluorescent protein-tagged insulin transfected in MIN6 β cells was packed in insulin secretory granules, which appeared to preferentially dock to the plasma membrane. Upon fusion evoked by secretagogues, Evanescent Wave microscopy revealed that fluorescence of green fluorescent protein-tagged insulin brightened, spread (within 300 ms), and then vanished. Under KCl stimulation, which represents the 1st phase of release, the successive fusion events were seen mostly from previously docked granules for the first minute, followed by the recruitment of new granules to the plasmalemmal docking sites. Stimulation with glucose, in contrast, caused the fusion events from previously docked granules for the first 120 s, thereafter a continuous fusion (2nd phase of release) was observed over 10 min mostly from newly recruited granules that progressively accumulated on the plasma membrane. Thus, our data revealed the distinct behavior of the insulin granule motion during the 1st and 2nd phase of release.
Wolfhard Almers - One of the best experts on this subject based on the ideXlab platform.
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fusion of constitutive membrane traffic with the cell surface observed by Evanescent Wave microscopy
Journal of Cell Biology, 2000Co-Authors: Derek Toomre, Jurgen A Steyer, Wolfhard Almers, Patrick Keller, Kai SimonsAbstract:Monitoring the fusion of constitutive traffic with the plasma membrane has remained largely elusive. Ideally, fusion would be monitored with high spatial and temporal resolution. Recently, total internal reflection (TIR) microscopy was used to study regulated exocytosis of fluorescently labeled chromaffin granules. In this technique, only the bottom cellular surface is illuminated by an exponentially decaying Evanescent Wave of light. We have used a prism type TIR setup with a penetration depth of ∼50 nm to monitor constitutive fusion of vesicular stomatitis virus glycoprotein tagged with the yellow fluorescent protein. Fusion of single transport containers (TCs) was clearly observed and gave a distinct analytical signature. TCs approached the membrane, appeared to dock, and later rapidly fuse, releasing a bright fluorescent cloud into the membrane. Observation and analysis provided insight about their dynamics, kinetics, and position before and during fusion. Combining TIR and wide-field microscopy allowed us to follow constitutive cargo from the Golgi complex to the cell surface. Our observations include the following: (1) local restrained movement of TCs near the membrane before fusion; (2) apparent anchoring near the cell surface; (3) heterogeneously sized TCs fused either completely; or (4) occasionally larger tubular-vesicular TCs partially fused at their tips.
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ca2 triggered peptide secretion in single cells imaged with green fluorescent protein and Evanescent Wave microscopy
Neuron, 1997Co-Authors: Thorsten Lang, Irene Wacker, Jurgen A Steyer, Christoph Kaether, Ilse Wunderlich, Thierry Soldati, Hans Herman Gerdes, Wolfhard AlmersAbstract:Abstract Green fluorescent protein fused to human chromogranin B or neuropeptide Y was expressed in PC12 cells and caused bright, punctate fluorescence. The fluorescent points colocalized with the endogenous secretory granule marker dopamine β-hydroxylase. Stimulation of live PC12 cells with elevated [K + ], or of permeabilized PC12 cells with Ca 2+ , led to Ca 2+ -dependent loss of fluorescence from neurites. Ca 2+ stimulated secretion of both fusion proteins equally well. In living cells, single fluorescent granules were imaged by Evanescent-Wave fluorescence microscopy. Granules were seen to migrate; to stop, as if trapped by plasmalemmal docking sites; and then to disappear abruptly, as if through exocytosis. Evidently, GFP fused to secreted peptides is a fluorescent marker for dense-core secretory granules and may be used for time-resolved microscopy of single granules.
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ca2 triggered peptide secretion in single cells imaged with green fluorescent protein and Evanescent Wave microscopy
Neuron, 1997Co-Authors: Thorsten Lang, Irene Wacker, Jurgen A Steyer, Christoph Kaether, Ilse Wunderlich, Thierry Soldati, Hans Herman Gerdes, Wolfhard AlmersAbstract:Green fluorescent protein fused to human chromogranin B or neuropeptide Y was expressed in PC12 cells and caused bright, punctate fluorescence. The fluorescent points colocalized with the endogenous secretory granule marker dopamine beta-hydroxylase. Stimulation of live PC12 cells with elevated [K+], or of permeabilized PC12 cells with Ca2+, led to Ca2+-dependent loss of fluorescence from neurites. Ca2+ stimulated secretion of both fusion proteins equally well. In living cells, single fluorescent granules were imaged by Evanescent-Wave fluorescence microscopy. Granules were seen to migrate; to stop, as if trapped by plasmalemmal docking sites; and then to disappear abruptly, as if through exocytosis. Evidently, GFP fused to secreted peptides is a fluorescent marker for dense-core secretory granules and may be used for time-resolved microscopy of single granules.
Virginie Nazabal - One of the best experts on this subject based on the ideXlab platform.
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Fiber Evanescent Wave spectroscopy based on IR fluorescent chalcogenide fibers
Sensors and Actuators B: Chemical, 2016Co-Authors: Radwan Chahal, Karine Michel, Bruno Bureau, Catherine Boussard-plédel, Florent Starecki, Jean-louis Doualan, Laurent Brilland, Alain Braud, Patrice Camy, Virginie NazabalAbstract:Chalcogenide glasses, owing to their transparency in the infrared window and the appropriate solubility of rare earth, allows the generation of middle infrared (mid-IR) radiation from a near infrared or visible pumping source. These emitted mid-IR broad bands can probe the vibrational modes of several molecules, e.g. C-H, CO or C-Cl. Relying on this principle, a mid-IR optical sensor using the mid-IR fluorescence of Pr3+: Ga-Ge-Sb-S fibers has been developed. The detection principle is based on Fiber Evanescent Wave Spectroscopy (FEWS). The spectroscopic characterization of praseodymium ions (Pr3+) was performed in the near and mid-IR and is discussed on the basis of comparison with Judd-Ofelt calculations. The broad emission spectrum of the Pr3+: Ga-Ge-Sb-S fiber from 4 to 5 μm could enable the monitoring of multiple pollutants. In this study, chloroform detection is carried out via a novel technique derived from FEWS. In this way, an infrared sensor was developed, composed of a pumping source in near-IR, a mid-IR detector and a tapered Pr3+: chalcogenide fiber to enhance the detection sensitivity. These results demonstrate for the first time the feasibility of detecting molecules by FEWS using the mid-IR fluorescence emitted by rare earth ions doping chalcogenide fibers. This method is an effective alternative to the classical FEWS system, as RE doped chalcogenide fibers have the advantage of being a compact mid-IR source
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Evanescent Wave optical micro-sensor based on chalcogenide glass
Sensors and Actuators B: Chemical, 2012Co-Authors: Joël Charrier, Marie-laure Brandily, Hervé Lhermite, Karine Michel, Bruno Bureau, Frédéric Verger, Virginie NazabalAbstract:A micro-sensor based on chalcogenide glasses was developed on oxidized silicon substrate for Evanescent Wave detection in near-infrared spectral domain. This micro-sensor is composed of ridge Waveguides based on chalcogenide glass deposited by RF magnetron sputtering associated with a microfluidic system. Optical losses of the ridge Waveguide were measured at 1.55 μm and were about of 0.4 dB/cm, a value sufficiently low to enable detection in near-IR spectral range by Evanescent Waves. Suitability of the sensor for chemical-sensing has been demonstrated by detecting phenylethylamine molecules absorbing specifically at 1.55 μm. The efficiency of the optical sensor was tested as a function of the phenylethylamine concentration in the solution and as a function of the Waveguide effective area. The best sensitivity was obtained for the Waveguide presenting the smallest effective area of about 1 μm × 1 μm when the attenuation was nearly linear with the phenylethylamine concentration. Experimentally, the resolution was about 0.1 mol L−1 and the sensitivity was 0.87 dB/(mol L−1). A theoretical study was set-up to better control the Evanescent Wave sensor performance in terms of sensitivity and of resolution of the optical chalcogenide micro-sensor. Finally, selenide micro-Waveguides were developed on CaF2 substrates suitable for detection in mid-IR spectral range.
Sarang Pendharker - One of the best experts on this subject based on the ideXlab platform.
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axial super resolution Evanescent Wave tomography
Optics Letters, 2016Co-Authors: Sarang Pendharker, Swapnali Shende, Ward D Newman, Stephen Ogg, Neda Nazemifard, Zubin JacobAbstract:Optical tomographic reconstruction of a three-dimensional (3D) nanoscale specimen is hindered by the axial diffraction limit, which is 2–3 times worse than the focal plane resolution. We propose and experimentally demonstrate an axial super-resolution Evanescent Wave tomography method that enables the use of regular Evanescent Wave microscopes like the total internal reflection fluorescence microscope beyond surface imaging and achieve a tomographic reconstruction with axial super-resolution. Our proposed method based on Fourier reconstruction achieves axial super-resolution by extracting information from multiple sets of 3D fluorescence images when the sample is illuminated by an Evanescent Wave. We propose a procedure to extract super-resolution features from the incremental penetration of an Evanescent Wave and support our theory by one-dimensional (along the optical axis) and 3D simulations. We validate our claims by experimentally demonstrating tomographic reconstruction of microtubules in HeLa cells with an axial resolution of ∼130 nm. Our method does not require any additional optical components or sample preparation. The proposed method can be combined with focal plane super-resolution techniques like stochastic optical reconstruction microscopy and can also be adapted for THz and microWave near-field tomography.
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axial super resolution Evanescent Wave tomography
arXiv: Optics, 2016Co-Authors: Sarang Pendharker, Swapnali Shende, Ward D Newman, Stephen Ogg, Neda Nazemifard, Zubin JacobAbstract:Optical tomographic reconstruction of a 3D nanoscale specimen is hindered by the axial diffraction limit, which is 2-3 times worse than the focal plane resolution. We propose and experimentally demonstrate an axial super-resolution Evanescent Wave tomography (AxSET) method that enables the use of regular Evanescent Wave microscopes like Total Internal Reflection Fluorescence Microscope (TIRF) beyond surface imaging, and achieve tomographic reconstruction with axial super-resolution. Our proposed method based on Fourier reconstruction achieves axial super-resolution by extracting information from multiple sets of three-dimensional fluorescence images when the sample is illuminated by an Evanescent Wave. We propose a procedure to extract super-resolution features from the incremental penetration of an Evanescent Wave and support our theory by 1D (along the optical axis) and 3D simulations. We validate our claims by experimentally demonstrating tomographic reconstruction of microtubules in HeLa cells with an axial resolution of $\sim$130 nm. Our method does not require any additional optical components or sample preparation. The proposed method can be combined with focal plane super-resolution techniques like STORM and can also be adapted for THz and microWave near-field tomography.
