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Scanned LSFM with Confocal Detection
Apr. 08, 2013

Scanned LSFM with Confocal Detection

Light sheet fluorescence microscopy (LSFM) is a technique with a vivid development [1, 2]. In contrast to epi-illumination microscopy the sample is illuminated with a thin light sheet orthogonally to the detection path. Most often the sheet is formed by rapidly scanning a laser beam across the sample. This illumination yields intrinsic optical sectioning and reduction of photobleaching and phototoxicity since excitation is limited to fluorophores inside the observation plane. This is particularly beneficial for long term imaging in developmental biology and reduces image background [3-5].
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Molecularly Resolved Cellulose Nitrate
Apr. 02, 2013

Molecularly Resolved Cellulose Nitrate

The development of nanostructured lacquers and propellants needs to master the cellulose nitrate processing on the nanoscale. The challenge is the deposition of single cellulose nitrate molecules to image them with molecular resolution. We report on the effect of solvent, shaking duration and deposition techniques, from which the spray technique succeeded, for the first time to our knowledge, to image by Atomic Force Microscopy, individual molecular cellulose nitrate polymeric chains.
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Nano-FTIR - The Chemical Nanoscope
Mar. 25, 2013

Nano-FTIR - The Chemical Nanoscope

We show identification of chemical compounds and chemical maps at 20 nm resolution, enabled by a novel combination of infrared spectroscopy and near-field microscopy. Nano-FTIR returns the surface topography and simultaneously the local mid-infrared spectrum of the tiny volume (20 nm3) just below the probing tip thus allowing correlative topography/hyperspectral infrared images. In the case of molecular substances, comparison with common infrared databases enables local chemical recognition.
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Light Sheet Ultramicroscopy
Mar. 18, 2013

Light Sheet Ultramicroscopy

We developed a new ultramicroscopy design equipped with modified optics to achieve 3D-vizualizations of specimens with μm-resolution. The optical unit consists of elements with complex surface structures to create an ultra-thin light sheet. Diffraction and other unwanted optical effects are minimized, while the laser energy is used more efficiently. This enables us to obtain marked enhancements in resolving fine details of specimens (e.g. fruit-flies, entire mouse brains, and mouse hippocampi).
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Single Electron Events in TEM
Mar. 14, 2013

Single Electron Events in TEM

Single Electron Events (SEE) have been used to quantify the point spread function of several cameras for Transmission Electron Microscopy (TEM). The spatial resolution is measured by the Single Electron Modulation Transfer Function (MTFSEE) compared with the MTF generated by standard knife edge experiment. In addition, the sensitivity of the camera as a function of high tension has been measured, showing an excellent Signal-to-Noise Ratio (SNR) from 300 kV down to 8 kV.
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New Insights on Electron Channeling
Mar. 04, 2013

New Insights on Electron Channeling

Electron channeling contrast imaging (ECCI) is a powerful technique for the quantitative characterization of deformation structures in the SEM. The coupling of ECCI with EBSD provides an efficient method to attain enhanced diffraction contrast in the SEM. The EBSD-based ECCI set-up allows the imaging of dislocation and nano-twin substructures in the SEM. Some examples of quantitative microstructural characterization on structural materials are provided.
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Fractal Dimension and Entropy of Biological Membrane
Feb. 26, 2013

Fractal Dimension and Entropy of Biological Membrane

Complexity of cell membrane poses difficulties to quantify corresponding morphology changes during cell life. To quantify it, we present an evaluation of entropy and fractal dimension of macrophage membranes from Atomic Force Microscopy (AFM) images before and after treatment with microtubule destabilizing or stabilizing agents. We show that entropy and fractal dimension are sensitive to the weak micromorphology changes produced by small concentrations and incubation times of these treatments.
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SEM and ESEM Observation of Stem Cells
Feb. 25, 2013

SEM and ESEM Observation of Stem Cells

Studying biological samples with scanning electron microscopy has specific requirements for their preparation. Sample drying is a particularly critical operation for objects such as cultured cells. The requirement for damaging drying step can be eliminated using environmental scanning electron microscopy. This study compares dried and wet samples of cultured human embryonic stem cells. It points to the advantages of both methods and to the complementarity of the information that they provide.
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