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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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Archeological Pottery SEM-EDS Analysis
Jan. 25, 2013

Archeological Pottery SEM-EDS Analysis

Archaeologists have identified several types of pigments used in ancestral Puebloan black-on-white painted pottery from the American Southwest. One type of pigment contains iron. The most widely used and available method of determining the elemental composition of these pigments has been scanning electron microscopy utilizing energy dispersive spectrometry (SEM-EDS).
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Pixel Size & Sensitivity
Jan. 21, 2013

Pixel Size & Sensitivity

The number of pixels in image sensors is of central importance for the image quality. There is a general tendency towards higher resolutions, because they are associated with higher information content. Higher resolutions mean smaller pixels. The sensitivity of the pixels is another important feature (characteristic) of an image sensor. Larger pixel image sensors are said to be more sensitive than smaller pixel sensors. more
Single Molecule View on Polymerization
Jan. 17, 2013

Single Molecule View on Polymerization

Single molecule fluorescence spectroscopy and microscopy techniques enable the analysis of diffusional processes for different polymerization systems at different conversions. The advantage of our techniques lies in the direct visualization of material heterogeneities evolving during the polymerization process by observing the diffusion of single molecules. Connecting single molecule behavior to polymerization kinetics and the structures and properties of the synthesized polymers is one of our main goals. more
Dynamic Wettability Study at Nanoscale
Jan. 08, 2013

Dynamic Wettability Study at Nanoscale

Quantitative wettability study at nanoscale was developed using transmitted electrons in the environmental scanning electron microscope. Water condensation was studied for the initial stages of nucleation and growth over nano-thick self supported water films. Irregularities at the water film boundaries constituted nucleation sites for filmwise and dropwise condensation. In situ imaging provided nanodroplet growth power law dependence and a dynamic study of coalescence events.
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“Trolling”-Mode Atomic Force Microscopy
Jan. 03, 2013

“Trolling”-Mode Atomic Force Microscopy

Imaging biological materials is one of the main branches of biomedical engineering. Particularly, imaging living cells at the single-cell level is highly important for fundamental understanding of cell behavior and its interaction with the extracellular matrix. The resolution of commonly used optical microscopy is limited by diffraction of light to ~200 nm. However, the major elements of the cell membrane such as transmembrane proteins, ion channels, cell adhesion proteins etc. are essentially nanostructures, which cannot be resolved with optical microscopy. more
Morphology of Nanoparticles
Dec. 20, 2012

Morphology of Nanoparticles

Potential candidates of reference nano-materials are manufactured and systematically characterized in particular with respect to their morphology (shape, size and size distribution) in the frame of the running large European project NanoValid. By exploiting the transmission operation mode in a SEM, known as T-SEM, it is demonstrated by means of three representative examples of nanoparticles how a quick morphological inspection up to a complete, metrological characterization is feasible.
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