Comparison of standard DIC and PhC images to their synthesized counterparts from cDPC.

<p>Ground truth DIC images were acquired using a 20x 0.75 NA objective and phase contrast images using a 20x 0.4 NA PhC objective. cDPC images were acquired using a 20x 0.4 NA objective and our filter insert.</p

Visualization 1: 3D differential phase contrast microscopy

Through focus of Embryos Originally published in Biomedical Optics Express on 01 October 2016 (boe-7-10-3940

Raw data, phase and amplitude reconstructions, synthesized phase contrast and DIC images for various samples and magnifications: micro-lens array (4x 0.1 NA), wild-type c. elegans (10x 0.25 NA), HEK 293T cells (20× 0.4 NA), MCF7 cells (20× 0.4 NA).

<p>Raw data, phase and amplitude reconstructions, synthesized phase contrast and DIC images for various samples and magnifications: micro-lens array (4x 0.1 NA), wild-type c. elegans (10x 0.25 NA), HEK 293T cells (20× 0.4 NA), MCF7 cells (20× 0.4 NA).</p

Single-shot quantitative phase microscopy with color-multiplexed differential phase contrast (cDPC)

<div><p>We present a new technique for quantitative phase and amplitude microscopy from a single color image with coded illumination. Our system consists of a commercial brightfield microscope with one hardware modification—an inexpensive 3D printed condenser insert. The method, color-multiplexed Differential Phase Contrast (cDPC), is a single-shot variant of Differential Phase Contrast (DPC), which recovers the phase of a sample from images with asymmetric illumination. We employ partially coherent illumination to achieve resolution corresponding to 2× the objective NA. Quantitative phase can then be used to synthesize DIC and phase contrast images or extract shape and density. We demonstrate amplitude and phase recovery at camera-limited frame rates (50 fps) for various <i>in vitro</i> cell samples and c. elegans in a micro-fluidic channel.</p></div

Experimental demonstration of motion blur reduction with cDPC vs. conventional DPC.

<p>Our cDPC method results in significantly reduced motion blur artifacts due to its single-shot acquisition.</p

Single-shot color Differential Phase Contrast (cDPC) microscopy.

<p>a) Optical schematic of a brightfield microscope with a cDPC color filter placed at the back focal plane of the condenser in Köhler configuration. b) Installation in Nikon TE300 microscope condenser turret. c) Reconstruction: the captured color image is separated into its RGB components, which are then used to recover two unknowns (amplitude and phase) via a well-posed linear deconvolution. The sample is a micro-lens array (Fresnel Technologies 605). d) CAD model and image of fabricated cDPC insert.</p

Experimental comparison of single-shot cDPC with monochromatic DPC and through-focus phase retrieval methods.

<p>(Left) Source patterns. (Middle) Raw camera measurements. (Right) Recovered optical field. DPC methods (partially coherent) were acquired using a 20× 0.4 NA objective lens, while through-focus images (spatially coherent) were captured using 60× 0.8 NA, in order to ensure equal resolution in all cases.</p

Transfer functions for amplitude and phase contrast in each cDPC color channel.

<p>Left: spectral contribution of each illumination filter as captured by the camera’s Bayer pattern. The following columns show the components of the source represented in each image, and the amplitude and phase transfer functions in the spatial frequency domain. Bottom row: sum of each column, representing the calibrated and scaled source and the total coverage of amplitude and phase transfer functions, respectively.</p

NH₄FeCl₂(HCOO): Synthesis, Structure, and Magnetism of a Novel Low-Dimensional Magnetic Material

Solvothermal synthesis was used to create a low-dimensional iron­(II) chloride formate compound, NH₄FeCl₂­(HCOO), that exhibits interesting magnetic properties. NH₄FeCl₂­(HCOO) crystallizes in the monoclinic space group <i>C</i>2/<i>c</i> (No. 15) with <i>a</i> = 7.888(1) Å, <i>b</i> = 11.156(2) Å, <i>c</i> = 6.920(2) Å, and β = 108.066(2)°. The crystal structure consists of infinite zigzag chains of distorted Fe²⁺-centered octahedra linked by μ₂-Cl and syn-syn formate bridges, with interchain hydrogen bonding through NH₄⁺ cations holding the chains together. The unique Fe²⁺ site is coordinated by four equatorial chlorides at a distance of 2.50 Å and two axial oxygens at a distance of 2.08 Å. Magnetic measurements performed on powder and oriented single-crystal samples show complex anisotropic magnetic behavior dominated by antiferromagnetic interactions (<i>T</i>_N = 6 K) with a small ferromagnetic component in the direction of chain propagation. An anisotropic metamagnetic transition was observed in the ordered state at 2 K in an applied magnetic field of 0.85–3 T. ⁵⁷Fe Mössbauer spectroscopy reveals mixed hyperfine interactions below the ordering temperature, with strong electric field gradients and complex noncollinear arrangement of the magnetic moments

Le Bordeaux médical

09 janvier 18771877/01/09 (A6,N2).Appartient à l’ensemble documentaire : Aquit