Diversity-Oriented A3-Macrocyclization for Studying Influences of Ring-Size and Shape of Cyclic Peptides: CD36 Receptor Modulators

Polymer components for liquid sealing applications are employed in a variety of potentially corrosive environments, such as seawater. Frequently, corrosion of the metal is found at or adjacent to the rubber-metal interface rather than at a noncontact area. The corrosion of different metal alloys (titanium, bronze, nickel, aluminum, 316 stainless steel, and 4130 steel) in combination with rubber O-rings (Buna-N and EPDM) of varying internal diameters and cross-sectional shapes in seawater over a period of four years is described herein. The corrosion of some metals (i.e., 4130 stainless steel) was found to be accelerated through interaction with Buna-N rubber O-rings. Theories to account for corrosion at the polymer-metal interface, especially with respect to polymer composition and O-ring size and shape, are discussed.

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Unbiased estimation of particle number and sizes using the new stereological tools: the disector, the fractionator, the selector, and the nucleator — or just point-sampled intercepts

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104200 ◽

1988 ◽

Vol 46 ◽

pp. 428-429

Author(s):

H.J.G. Gundersen

Keyword(s):

Particle Number ◽

Small Distance ◽

Parallel Plane ◽

Unbiased Estimation ◽

Severe Problem ◽

New Era ◽

Size And Shape ◽

Distinct Property ◽

Sectioned Tissue

Previously, all stereological estimation of particle number and sizes were based on models and notoriously gave biased results, were very inefficient to use and difficult to justify. For all references to old methods and a direct comparison with unbiased methods see recent reviews.The publication in 1984 of the DISECTOR, the first unbiased stereological probe for sampling and counting 3—D objects irrespective of their size and shape, signalled the new era in stereology — and give rise to a number of remarkably simple and efficient techniques based on its distinct property: It is the only known way to obtain an unbiased sample of 3-D objects (cells, organelles, etc). The principle is simple: within a 2-D unbiased frame count or sample only cells which are not hit by a parallel plane at a known, small distance h.The area of the frame and h must be known, which might sometimes in itself be a problem, albeit usually a small one. A more severe problem may arise because these constants are known at the scale of the fixed, embedded and sectioned tissue which is often shrunken considerably.

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The influence of confocal microscope design on imaging performance

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146564 ◽

1993 ◽

Vol 51 ◽

pp. 144-145

Author(s):

C J R Sheppard

Keyword(s):

Image Quality ◽

Fluorescence Imaging ◽

Confocal Microscope ◽

Industrial Applications ◽

Three Dimensions ◽

Design Parameters ◽

Weak Signals ◽

Size And Shape ◽

Imaging Performance ◽

Fundamental Limitation

The confocal microscope is now widely used in both biomedical and industrial applications for imaging, in three dimensions, objects with appreciable depth. There are now a range of different microscopes on the market, which have adopted a variety of different designs. The aim of this paper is to explore the effects on imaging performance of design parameters including the method of scanning, the type of detector, and the size and shape of the confocal aperture.It is becoming apparent that there is no such thing as an ideal confocal microscope: all systems have limitations and the best compromise depends on what the microscope is used for and how it is used. The most important compromise at present is between image quality and speed of scanning, which is particularly apparent when imaging with very weak signals. If great speed is not of importance, then the fundamental limitation for fluorescence imaging is the detection of sufficient numbers of photons before the fluorochrome bleaches.

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