Determination of transition curves of high-Tc superconductors by phase contrast microscopy

1995 ◽  
Vol 507 (2) ◽  
pp. 136-143
Author(s):  
Cl. Kriebel ◽  
O. Hoffels ◽  
R. Borowski ◽  
H. Gottschalk ◽  
H. Alexander ◽  
...  
Keyword(s):  
Phase Contrast ◽  
Phase Contrast Microscopy ◽  
High Tc Superconductors ◽  
High Tc ◽  
Contrast Microscopy ◽  
Transition Curves

Increased Fraction of Circulating Activated Platelets in Acute and Previous Cerebrovascular Ischemia

1998 ◽  
Vol 80 (08) ◽  
pp. 298-301 ◽  
Author(s):  
Andreas Ruf ◽  
Axel Vogt ◽  
Christoph Lichy ◽  
Florian Buggle ◽  
Heinrich Patscheke ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Phase Contrast ◽  
Matched Control ◽  
Shape Change ◽  
Antigen Expression ◽  
Phase Contrast Microscopy ◽  
Activated Platelets ◽  
Contrast Microscopy ◽  
Age And Sex

SummaryDetermination of circulating activated platelets may be helpful to estimate the prognosis and to stratify therapies in arterial vascular disorders including stroke. We used flow cytometry and phase contrast microscopy to study whether the fraction of platelets expressing p-selectin and CD63 and the fraction of platelets with shape change are increased in patients with acute and previous cerebrovascular ischemia.The proportion of platelets expressing activation dependent antigens was higher in patients with acute (n = 24; p-selectin: 8.23 ± 4.21%; CD63: 3.53 ± 2.53%) and with previous cerebrovascular ischemia (n = 46; 3.86 ± 1.98%; 2.80 ± 1.79%) as compared to age- and sex-matched control subjects (n = 35; 2.17 ± 0.96%; 1.79 ± 0.75%; p ≤0.005, respectively). In patients with previous ischemia, there was no difference between treatment with aspirin (n = 25) or phenprocoumon (n = 21). Hypertension, diabetes mellitus and smoking were not associated with increased antigen expression (analysis of variance). The fraction of discoid platelets and platelet counts were not significantly different between groups.Our results indicate increased expression of platelet neoantigens in acute and to a less degree in previous cerebrovascular ischemia. Ongoing platelet activation after cerebrovascular ischemia despite therapy with aspirin or phenprocoumon indicates that new anti-platelet drugs may be of benefit for these patients. Flow cytometry appears to be a useful tool to assess platelet function in cerebrovascular ischemia.

Integral refractive index determination of living suspension cells by multifocus digital holographic phase contrast microscopy

2007 ◽  
Vol 12 (5) ◽  
pp. 054009 ◽  
Author(s):  
Björn Kemper ◽  
Sebastian Kosmeier ◽  
Patrik Langehanenberg ◽  
Gert von Bally ◽  
Ilona Bredebusch ◽  
...  
Keyword(s):  
Refractive Index ◽  
Phase Contrast ◽  
Phase Contrast Microscopy ◽  
Suspension Cells ◽  
Contrast Microscopy

Determination of the integral refractive index of cells in suspension by digital holographic phase contrast microscopy

2008 ◽  
Author(s):  
Sebastian Kosmeier ◽  
Björn Kemper ◽  
Patrik Langehanenberg ◽  
Ilona Bredebusch ◽  
Jürgen Schnekenburger ◽  
...  
Keyword(s):  
Refractive Index ◽  
Phase Contrast ◽  
Phase Contrast Microscopy ◽  
Contrast Microscopy ◽  
Refractive Index Of Cells

An interferometer microscope

1950 ◽  
Vol 204 (1077) ◽  
pp. 170-187 ◽  
Keyword(s):  
Refractive Index ◽  
Epithelial Cells ◽  
Optical Thickness ◽  
Phase Contrast ◽  
Phase Contrast Microscopy ◽  
Object Plane ◽  
Operational Procedure ◽  
Contrast Microscopy ◽  
New Type

Some of the drawbacks of conventional phase contrast microscopy are enumerated and the desirability of an interferometer microscope is indicated. A number of existing ways of achieving this are described, together with their merits and drawbacks. A new type of interferometer microscope which avoids some of these disadvantages is described, together with its operational procedure. The conditions covering coherence in the object plane are investigated and a simple approximation for evaluating the coherence is derived. An elementary discussion of contrast arising from phase or amplitude objects is given, and a number of experimental results are presented as photo-micrograms. Finally, a method for the accurate measurement of the optical thickness of an object is described, with the results of a determination of the refractive index of the cytoplasm of epithelial cells.

The many faces of STEM in materials science

1991 ◽  
Vol 49 ◽  
pp. 440-441
Author(s):  
John Silcox
Keyword(s):  
Materials Science ◽  
Auger Spectroscopy ◽  
Dark Field ◽  
High Tc Superconductors ◽  
High Tc ◽  
Acoustic Environment ◽  
Electromagnetic Vibration ◽  
The Many ◽  
Serial Mode

Determination of the microstructure and microchemistry of small features often provides the insight needed for the understanding of processes in real materials. In many cases, it is not adequate to use microscopy alone. Microdiffraction and microspectroscopic information such as EELS, X-ray microprobe analysis and Auger spectroscopy can all contribute vital parts of the picture. For a number of reasons, dedicated STEM offers considerable promise as a quantitative instrument. In this paper, we review progress towards effective quantitative use of STEM with illustrations drawn from studies of high Tc superconductors, compound semiconductors and metallization of H-terminated silicon.Intrinsically, STEM is a quantitative instrument. Images are acquired directly by detectors in serial mode which is particularly convenient for digital image acquisition, control and display. The VG HB501A at Cornell has been installed in a particularly stable electromagnetic, vibration and acoustic environment. Care has been paid to achieving UHV conditions (i.e., 10-10 Torr). Finally, it has been interfaced with a VAX 3200 work station by Kirkland. This permits, for example, the acquisition of bright field (or energy loss) images and dark field images simultaneously as quantitative arrays in perfect registration.

scholarly journals Rough Dental Implant Surfaces and Peri-Implantitis: Role of Phase-Contrast Microscopy, Laser Protocols, and Modified Home Oral Hygiene in Maintenance. A 10-Year Retrospective Study

2021 ◽  
Vol 11 (11) ◽  
pp. 4985
Author(s):  
Gianluigi Caccianiga ◽  
Gérard Rey ◽  
Paolo Caccianiga ◽  
Alessandro Leonida ◽  
Marco Baldoni ◽  
...  
Keyword(s):  
Retrospective Study ◽  
Phase Contrast ◽  
Vertical Movement ◽  
Subgingival Plaque ◽  
Phase Contrast Microscopy ◽  
Implant Surface ◽  
Total Percentage ◽  
Contrast Microscopy

The aim of this study was to evaluate two different kinds of rough implant surface and to assess their tendency to peri-implantitis disease, with a follow-up of more than 10 years. Data were obtained from a cluster of 500 implants with Ti-Unite surface and 1000 implants with Ossean surface, with a minimum follow-up of 10 years. Implants had been inserted both in pristine bone and regenerated bone. We registered incidence of peri-implantitis and other causes of implant loss. All patients agreed with the following maintenance protocol: sonic brush with vertical movement (Broxo), interdental brushes, and oral irrigators (Broxo) at least two times every day. For all patients with implants, we evaluated subgingival plaque samples by phase-contrast microscopy every 4 months for a period of more than 10-years. Ti-Unite surface implants underwent peri-implantitis in 1.6% of the total number of implants inserted and Ossean surface implants showed peri-implantitis in 1.5% of the total number of implants. The total percentage of implant lost was 4% for Ti-Unite surfaces and 3.6% for Ossean surfaces. Strict control of implants leads to low percentage of peri-implantitis even for rough surfaces dental implants.

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