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M Schwertner

Publications and source records attributed to M Schwertner.

5 recordsLinked to original sources
PubMed2005

Simple optimization procedure for objective lens correction collar setting.

We present a new method for setting a coverglass correction collar on an objective lens. Axial scans across the interface between the specimen volume and the slide are used together with a quantitative function of merit to determine the optimum setting of the correction collar. The method, which simplifies the adjustment for the user and reduces photobleaching, was implemented within the software environment of a scanning microscope system.

Journal Article↗
PubMed2004

Simulation of specimen-induced aberrations for objects with spherical and cylindrical symmetry.

Wavefront aberrations caused by the refractive index structure of the specimen are known to compromise signal intensity and three-dimensional resolution in confocal and multiphoton microscopy. However, adaptive optics can measure and correct specimen-induced aberrations. For the design of an adaptive optics system, information on the type and amount of the aberration is required. We have previously described an interferometric set-up capable of measuring specimen-induced aberrations and a method for the extraction of the Zernike mode content. In this paper we have modelled specimen-induced aberrations caused by spherical and cylindrical objects using a ray tracing method. The Zernike mode content of the wavefronts was then extracted from the simulated wavefronts and compared with experimental results. Aberrations for a simple model of an oocyte cell consisting of two spherical regions and for a model of a well-characterized optical fibre are calculated. This simple model gave Zernike mode data that are in good agreement with experimental results.

Animals↗
PubMed2004

Measurement of specimen-induced aberrations of biological samples using phase stepping interferometry.

Confocal or multiphoton microscopes, which deliver optical sections and three-dimensional (3D) images of thick specimens, are widely used in biology. These techniques, however, are sensitive to aberrations that may originate from the refractive index structure of the specimen itself. The aberrations cause reduced signal intensity and the 3D resolution of the instrument is compromised. It has been suggested to correct for aberrations in confocal microscopes using adaptive optics. In order to define the design specifications for such adaptive optics systems, one has to know the amount of aberrations present for typical applications such as with biological samples. We have built a phase stepping interferometer microscope that directly measures the aberration of the wavefront. The modal content of the wavefront is extracted by employing Zernike mode decomposition. Results for typical biological specimens are presented. It was found for all samples investigated that higher order Zernike modes give only a small contribution to the overall aberration. Therefore, these higher order modes can be neglected in future adaptive optics sensing and correction schemes implemented into confocal or multiphoton microscopes, leading to more efficient designs.

Animals↗
PubMedDate not supplied

Forging a vital link in group operations.

Medical secretaries play a vital role in group practice; and for maximum productivity, it is essential that they be adequately trained. At the Scott and White Clinic in Temple, Texas, a thorough examination was conducted of the medical secretary training program. Based on this, a more formal program was developed which included a series of self-directed, competency-based learning modules with built-in program effectiveness monitors. The result of strengthening this one link in the chain of group operations has been not only better qualified and happier secretaries, but also, increased overall productivity. This article contains the key to developing, introducing, implementing, and evaluating a successful medical secretary training program in your group practice.

Competency-Based Education↗