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Super resolution

Genevieve Vigil, Yide Zhang, Aamir Khan, Scott Howard
Here we recount the standard two-level model that describes saturated excitation (SAX) in multiphoton microscopy (MPM), a new technique for super-resolution fluorescence microscopy in scattering tissue, which requires no special chemistry and only simple modifications to a commercial MPM microscope. We use the model to study conditions required for improvements in MPM SAX resolution and experimental implementation strategies. Simulation results find zeros, or nodes, in the frequency response, which generate highly irregular point-spread functions (PSFs), such as rings and ripples, that contain spatial frequency content >3× larger than allowed by diffraction...
July 1, 2017: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
Jonathan T Richard, Martin S Heimbeck, L Blake Autin, Henry O Everitt
The combination of wide bandwidth W-band inverse synthetic aperture radar imagery and high-fidelity numerical simulations has been used to identify distinguishing signatures from simple metallic and dielectric targets. Targets are located with millimeter-scale accuracy using super-resolution techniques. Radon transform reconstructions of the returns from rotated targets approached the image quality of the complete data set in a fraction of the time by sampling as few as 10 angles. The limitations of shooting-and-bouncing ray simulations at high frequencies are illustrated through a critical comparison of their predictions with the measured data and the method of moments simulations, indicating the importance of accurately capturing the obfuscating role played by multipath interference in complex targets...
July 1, 2017: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
Zhongsheng Man, Shenggui Fu, Gongxiang Wei
Highly confined electromagnetic fields with controllable intensity profiles and polarization orientations are greatly desired in many fields. In this paper, we report on the generation of highly confined fields through tightly focused locally linearly polarized beams. Using the Richards-Wolf vectorial diffraction method, we derive and build integrated analytical formulae for calculating the tightly focused field of polarized beams with arbitrary geometric configurations of linear polarization. Based on the analytical model, the focusing properties of four types of polarized light beams, i...
August 1, 2017: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
Byeongho Moon, Soohwan Yu, Seungyong Ko, Seonhee Park, Joonki Paik
This paper presents a digital zooming method using a super-resolution (SR) algorithm based on the local self-similarity between the wide- and tele-view images acquired by an asymmetric dual camera system. The proposed SR algorithm consists of four steps: (i) registration of an optically zoomed image to the wide-view image, (ii) restoration of the central region of the zoomed wide-view image, (iii) restoration of the boundary region of the zoomed wide-view image, and (iv) fusion of the results from steps (ii) and (iii)...
June 1, 2017: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
Katharine R Smith, Kelly A Jones, Katherine J Kopeikina, Alain C Burette, Bryan A Copits, Sehyoun Yoon, Marc Forrest, Jessica M Fawcett-Patel, Jonathan G Hanley, Richard J Weinberg, Geoffrey T Swanson, Peter Penzes
Appropriate excitatory-inhibitory (E/I) balance is essential for normal cortical function and is altered in some psychiatric disorders, including autism spectrum disorders (ASDs). Cell-autonomous molecular mechanisms that control the balance of excitatory and inhibitory synapse function remain poorly understood; no proteins that regulate excitatory and inhibitory synapse strength in a coordinated reciprocal manner have been identified. Using super-resolution imaging, electrophysiology, and molecular manipulations we show that cadherin-10, encoded by CDH10 within the ASD risk locus 5p14...
October 13, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Gleb Vladimirov, Yury Kostyukevich, Oleg Kharybin, Eugene Nikolaev
Particle-in-cell-based realistic simulation of Fourier transform ion cyclotron resonance experiments could be used to generate ion trajectories and a signal induced on the detection electrodes. It has been shown recently that there is a modulation of "reduced" cyclotron frequencies in ion cyclotron resonance signal caused by Coulomb interaction of ion clouds. In this work it was proposed to use this modulation in order to determine frequency difference between an ion of known m/z and all other ions generating signal in ion cyclotron resonance cell...
August 2017: European Journal of Mass Spectrometry
Laurence J Young, Gabriele S Kaminski Schierle, Clemens F Kaminski
The major hallmark of Alzheimer's disease is the deposition of plaques of amyloid fibrils formed from amyloid-β (Aβ) peptides. Kinetic studies have contributed significantly towards a mechanistic understanding of amyloid fibril self-assembly, however dynamic features of the aggregation process cannot be captured using ensemble methods. Here we present an assay for imaging Aβ42 aggregation dynamics at the single fibril level, allowing for the quantitative extraction of concentration and temperature dependent kinetic parameters...
October 13, 2017: Physical Chemistry Chemical Physics: PCCP
Andrew M Fry, Josephina Sampson, Caroline Shak, Sue Shackleton
The centrosome is an unusual organelle that lacks a surrounding membrane, raising the question of what limits its size and shape. Moreover, while electron microscopy (EM) has provided a detailed view of centriole architecture, there has been limited understanding of how the second major component of centrosomes, the pericentriolar material (PCM), is organized. Here, we summarize exciting recent findings from super-resolution fluorescence imaging, structural biology, and biochemical reconstitution that together reveal the presence of ordered layers and complex gel-like scaffolds in the PCM...
2017: F1000Research
Maryam Zarghani, Hadi Parastar
The objective of the present work is development of joint approximate diagonalization of eigenmatrices (JADE) as a member of independent component analysis (ICA) family, for the analysis of gas chromatography-mass spectrometry (GC-MS) and comprehensive two-dimensional gas chromatography-mass spectrometry (GC×GC-MS) data to address incomplete separation problem occurred during the analysis of complex sample matrices. In this regard, simulated GC-MS and GC×GC-MS data sets with different number of components, different degree of overlap and noise were evaluated...
September 27, 2017: Journal of Chromatography. A
Mingjun Wang, Shaodong Feng, Jigang Wu
We report a multilayer lensless in-line holographic microscope (LIHM) with improved imaging resolution by using the pixel super-resolution technique and random sample movement. In our imaging system, a laser beam illuminated the sample and a CMOS imaging sensor located behind the sample recorded the in-line hologram for image reconstruction. During the imaging process, the sample was moved by hand randomly and the in-line holograms were acquired sequentially. Then the sample image was reconstructed from an enhanced-resolution hologram obtained from multiple low-resolution in-line holograms by applying the pixel super-resolution (PSR) technique...
October 6, 2017: Scientific Reports
Ai Milojevic, Claire L Niedzwiedz, Jamie Pearce, James Milner, Ian A MacKenzie, Ruth M Doherty, Paul Wilkinson
BACKGROUND: Socioeconomically disadvantaged populations often have higher exposures to particulate air pollution, which can be expected to contribute to differentials in life expectancy. We examined socioeconomic differentials in exposure and air pollution-related mortality relating to larger scale (5 km resolution) variations in background concentrations of selected pollutants across England. METHODS: Ozone and particulate matter (sub-divided into PM10, PM2.5, PM2...
October 6, 2017: Environmental Health: a Global Access Science Source
Molly Parkyn Schneider, Boyin Liu, Philipp Glock, Annika Suttie, Emma McHugh, Dean Andrew, Steven Batinovic, Nicholas Williamson, Eric Hanssen, Paul McMillan, Marion Hliscs, Leann Tilley, Matthew W A Dixon
Transmission of malaria parasites relies on the formation of a specialized blood form called the gametocyte. Gametocytes of the human pathogen, Plasmodium falciparum, adopt a crescent shape. Their dramatic morphogenesis is driven by the assembly of a network of microtubules and an underpinning inner membrane complex (IMC). Using super-resolution optical and electron microscopies we define the ultrastructure of the IMC at different stages of gametocyte development. We characterize two new proteins of the gametocyte IMC, called PhIL1 and PIP1...
October 6, 2017: PLoS Pathogens
Shawn T Terryah, Robert C Fellner, Saira Ahmad, Patrick John Moore, Boris Reidel, Juliana I Sesma, Christine S Kim, Alaina L Garland, David W Scott, Juan R Sabater, Jerome Carpenter, Scott H Randell, Mehmet Kesimer, William M Abraham, William J Arendshorst, Robert Tarran
In cystic fibrosis (CF) lungs, epithelial Na+ channel (ENaC) hyperactivity causes a reduction in airway surface liquid (ASL) volume, leading to decreased mucocilliary clearance and lung damage. Inhibition of ENaC is an attractive therapeutic option. However, ENaC antagonists have failed clinically due to off-target renal effects. The S18 peptide is a naturally occurring short palate lung and nasal epithelial clone 1 (SPLUNC1)-derived ENaC antagonist that restores ASL height for up to 24 h in CF human bronchial epithelial cultures...
October 5, 2017: American Journal of Physiology. Lung Cellular and Molecular Physiology
Marjeta Lisjak, Maja Potokar, Boštjan Rituper, Jernej Jorgačevski, Robert Zorec
Water channel aquaporin 4 (AQP4) plays a key role in the regulation of water homeostasis in the brain. It is predominantly expressed in astrocytes at blood-brain and blood-liquor interfaces. Although several AQP4 isoforms have been identified in the mammalian brain, two, AQP4a (M1) and AQP4c (M23), have been confirmed to cluster into plasma membrane supramolecular structures, termed orthogonal arrays of particles (OAPs) and to enhance water transport through the plasma membrane. However, the role of the newly described water-conductive mammalian isoform AQP4e is unknown...
October 4, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Dongyu Li, Wei Qin, Bin Xu, Jun Qian, Ben Zhong Tang
Stimulated emission depletion (STED) nanoscopy is a typical super-resolution imaging technique that has become a powerful tool for visualizing intracellular structures on the nanometer scale. Aggregation-induced emission (AIE) luminogens are ideal fluorescent agents for bioimaging. Herein, long-term super-resolution fluorescence imaging of cancer cells, based on STED nanoscopy assisted by AIE nanoparticles (NPs) is realized. 2,3-Bis(4-(phenyl(4-(1,2,2-triphenylvinyl)phenyl)amino)phenyl) fumaronitrile (TTF), a typical AIE luminogen, is doped into colloidal mesoporous silica to form fluorescent NPs...
October 4, 2017: Advanced Materials
Manoël Prouteau, Ambroise Desfosses, Christian Sieben, Clélia Bourgoint, Nour Lydia Mozaffari, Davide Demurtas, Alok K Mitra, Paul Guichard, Suliana Manley, Robbie Loewith
The target of rapamycin (TOR) is a eukaryotic serine/threonine protein kinase that functions in two distinct complexes, TORC1 and TORC2, to regulate growth and metabolism. GTPases, responding to signals generated by abiotic stressors, nutrients, and, in metazoans, growth factors, play an important but poorly understood role in TORC1 regulation. Here we report that, in budding yeast, glucose withdrawal (which leads to an acute loss of TORC1 kinase activity) triggers a similarly rapid Rag GTPase-dependent redistribution of TORC1 from being semi-uniform around the vacuolar membrane to a single, vacuole-associated cylindrical structure visible by super-resolution optical microscopy...
October 12, 2017: Nature
Ben E Urban, Lei Xiao, Biqin Dong, Siyu Chen, Yevgenia Kozorovitskiy, Hao F Zhang
Visualizing fine neuronal structures deep inside strong light-scattering brain tissue remains a challenge in neuroscience. Recent nanoscopy techniques have reached the necessary resolution, but often suffer from limited imaging depth, long imaging time, or high light fluence requirements. Here, we present two-photon Super-resolution Patterned Excitation Reconstruction (2P-SuPER) microscopy for three-dimensional imaging of dendritic spine dynamics at a maximum demonstrated imaging depth of 130 μm in living brain tissue with approximately 100 nm spatial resolution...
October 4, 2017: Journal of Biophotonics
Richard Lincoln, Lana E Greene, Wenzhou Zhang, Sheena Louisia, Gonzalo Cosa
Protein and DNA alkylation by endogenously produced electrophiles is associated with the pathogenesis of neurodegenerative diseases, to epigenetic alterations and to cell signaling and redox regulation. With the goal of visualizing, in real-time, the spatiotemporal response of the cell milieu to electrophiles, we have designed a fluorogenic BODIPY-acrolein probe, AcroB, that undergoes a >350-fold fluorescence intensity enhancement concomitant with protein adduct formation. AcroB enables a direct quantification of single post-translational modifications occurring on cellular proteins via recording fluorescence bursts in live-cell imaging studies...
October 13, 2017: Journal of the American Chemical Society
Sreejesh Sreedharan, Martin Gill, Esther Garcia, Hiwa K Saeed, Darren Robinson, Aisling Byrne, Ashley James Cadby, Tia E Keyes, Carl G W Smythe, Patrina Pellett, Jorge Bernardino de la Serna, Jim Antony Thomas
Detailed studies on the live cell uptake properties of a dinuclear membrane permeable permeable RuII cell probe show that, at low concentrations, the complex localizes and images mitochondria. At concentrations above ~20 μM the complex images nuclear DNA. Since the complex is extremely photostable, has a large Stokes shift, and displays intrinsic subcellular targeting, its compatibility with super-resolution techniques was investigated. It was found to be very well suited to image mitochondria and nuclear chromatin in two col-our, 2C-SIM; and STED and 3D-STED both in fixed and live cell...
October 4, 2017: Journal of the American Chemical Society
Hua He, Xu Liu, Shan Li, Xiaojuan Wang, Qian Wang, Jiqiang Li, Junying Wang, Hao Ren, Baosheng Ge, Shengjie Wang, Xiao-Dong Zhang, Fang Huang
Molecular fluorescence blinking provides a simple and attractive way to achieve super-resolution localization via conventional fluo-rescence microscopy. However, success in super-resolution imaging relies heavily on their blinking characteristics. We here report easily prepared and photostable nanoparticles-carbon dots (CDs) -with desirable fluorescence blinking for high-density super-resolution imaging. The CDs exhibit a low duty cycle (~ 0.003) and high photon output (~ 8000) per switching event, as well as show much higher resistance to photobleaching than Alexa 647 or Cy5 typically used in single molecule localization microscopy...
October 4, 2017: Analytical Chemistry
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