May. 21, 2012

Digital Holographic Phase Microscopy

We explored a method to determine the refractive index of the cytoplasm by using microspheres that have been incorporated by living cells as reference in quantitative digital holographic phase contrast microscopy images. As many cells show a phagocytic behavior the method may be used with a variety of different cell types.
moreMay. 14, 2012

Strain Mapping at Al-Pb Interfaces

This Transmission Electron Microscope (TEM) investigation uses the retrieved complex exit-wave function in combination with the geometric phase analysis (GPA) to analyze strain located at faceted Al-Pb hetero-interfaces. It was found that the outer regions of a Pb nanoparticle were strained (compressed) which explains, according to the Clapeyron equation, an elevated melting in terms of interface strain.
moreMay. 07, 2012

Nanomechanical Properties of Materials

Despite the success of the Atomic Force Microscope operating in intermittent contact for microstructural characterization, important questions remain about the physical origin of the image contrast. A new technique (named Peak Force Tapping) based on the real time force distance curve analysis has been recently introduced to map the nanomechanical properties of materials (such as stiffness, adhesion, deformation, dissipation) simultaneously to the topography, with much higher resolution and less damage.
moreApr. 30, 2012

Diagnostic Transmission Electron Microscopy

The high resolution and sensitivity of electron microscopy is still a valuable tool, and for some diseases it is the gold standard in pathological diagnosis. Today the sample turnaround time for processing in the lab can be significantly reduced from days to hours by the microwave technology. In urgent clinical cases, microwave-assisted tissue processing, in combination with digital image acquisition, enables a "same-day" diagnosis. Ultrastructural telepathology allows instant and live second opinion retrieval from a remote expert worldwide.
moreApr. 19, 2012

Shear Localization in Gamma-Based Titanium Aluminides

Hot-working of intermetallic γ titanium aluminides is often hampered by their liability to shear localization and subsequent crack formation, thereby preventing a refinement of the microstructure by dynamic recrystallization. The mechanisms leading to shear localization and cracking were microstructurally analyzed using scanning (SEM) and transmission (TEM) electron microscopic techniques.
moreApr. 10, 2012

Quantitative Phase Microscopy

Classical phase contrast microscopy techniques allow only non-quantitative partial visualization of transparent samples. In recent years, a variety of techniques have appeared for complete phase determination with different levels of complexity. A new simple non-interferometric method able to provide real time quantitative optical path difference information is presented. It is based on the use of a refractive pyramid to measure the transillumination wavefront gradient using incoherent light.

Introduction
moreMar. 29, 2012

Analyzing Biomaterials by Nanofocus Computed Tomography

3D biomaterials are known to function as alternative bone grafts. In the area of Tissue Engineering (TE) 3D matrices are often used in combination with mesenchymal stem cells to build up a functional tissue graft. In this approach the selection of a matrix is a crucial factor. For bone TE applications the matrix should fulfill the following geometrical properties. moreMar. 20, 2012

Coherence Probe Microscopy - Contrast Modification and Image Enhancement

Coherence probe microscopy represents a contemporary method for non-destructive investigation of micro-materials providing depth resolved information about the sub-surface domain. We present that Fourier plane filtering can be integrated in such a low-coherence interferometric imaging system and demonstrate how image contrast can be modified and enhanced, similar to microscopy but now additionally in a depth-resolved way. Thereby we focus on weakly scattering technical multi-layer structures.
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