image description

The Microscope - Volume 59, First Quarter 2011

IN THIS ISSUE:

On the cover: Original specimen packets prepared by Antony van Leeuwenhoek and sent to London in 1687 consisted of “heavenly paper” (right) and two examples he produced by drying algal films. See Critical Focus: The Story of the Leeuwenhoek Specimens by Brian J. Ford.


Editorial | Food: Microscopy for Thought

Gary J. Laughlin
The Microscope 59 (1), p ii
Excerpt: Scientists and engineers employed in the food industry must address a number of key issues concerning food production and safety. More than ever, they find themselves in need of advanced technical training to meet today’s industry demands. Advocates of food safety (aren’t we all?) will be glad to know that pathogens are a chief concern among industry and regulatory agencies – for the obvious purposes of improving food safety and human wellbeing – while contamination remains a common cause of product-related consumer complaints.  Full article (PDF)


Differentiation of Erionite From Other Fibrous Zeolites by Central Stop Dispersion Staining: A Preliminary PLM Investigation

Lou Solebello and Gary Tomaino
The Microscope 59 (1), pp 3-9
Abstract: Erionite is a fibrous zeolite often difficult to differentiate from other fibrous zeolites by polarized light microscopy (PLM) and other techniques. It is associated with increased risks of mesothelioma-like cancers documented from population studies conducted in the Cappadocian region of Turkey during the 1970s. The studies are important because they initiated a growing awareness that fibrous mineral carcinogeneity is a function of asbestiform habit not restricted to the six minerals currently classified as asbestos. Erionite is an IARC Group 1 carcinogen that includes asbestos, but it is currently not regulated by the U.S. Environmental Protection (EPA) in the same manner as asbestos. The EPA has stated that erionite causes lung cancer in lab rats, and it is currently conducting studies with the North Dakota Department of Health, which may lead to the inclusion of erionite into the asbestos mineral classification. This paper discusses analyses performed on eight fibrous zeolite specimens for documented localities, causes for potential misclassification errors based on traditional methods of analysis, and an investigation of the possibility of using central stop dispersion staining with a 1.48 high dispersion (HD) refractive index liquid for differentiation of erionite from some other fibrous zeolites.  Full article (PDF)


Critical Focus | The Story of the Leeuwenhoek Specimens

Brian J. Ford
The Microscope 59 (1), pp 11-19
Excerpt: My briefcase sat on the shelf next to Sir Isaac Newton’s telescope. On the desk lay letters written by Antony van Leeuwenhoek in the 1670s. The soft sounds of climate control murmured in the background of an otherwise silent cellar. I was in the basement of the Royal Society in the center of London. It was February 1981, 30 years ago, yet it seems like last week. I was about to make one of the most thrilling discoveries one can imagine.  Full article (PDF)


A Make-Model-Year Case Involving Unusual Primer Chemistry and Good Resources

Diana M. Wright
The Microscope 59 (1), pp 21-28. Originally published online in the Journal of the American Society of Trace Evidence Examiners, Vol. 1, No. 2, December 2010, www.asteetrace.org.
Abstract: The case example presented will describe how the FBI Laboratory was able to develop investigative lead information in a hit-and-run fatality using resources such as the Paint Data Query (PDQ) database, automotive paint supplier contacts and refinish color pages, and the Internet. This case highlights the utility of a database such as PDQ in providing spectral data of known paint layers that can be directly compared to the layers analyzed in a paint chip recovered from a crime scene. Conversely, this case also depicts the limitations inherent in a database compiled from the relatively limited pool of vehicles that were sampled primarily from salvage yards by participating partner laboratory systems. Such a database can only be as broad as the population available for sampling, and gaps in representation are to be expected. Nonetheless, compelling investigative lead information was reported to the contributor using the described resources, most of which are readily available or can be developed by every laboratory system conducting these types of automotive paint examinations.  Full article (PDF)


Introducing Children to the Micro Life of Fish Lake

Theodore M. Clarke and JoAnn M. Burke
The Microscope 59 (1), pp 29-31
Abstract: My friend’s family and I have enjoyed exploring the live micro life of Fish Lake in rural Indiana. We collected our water samples near the shore and examined the specimens in a micro aquarium slide using a Meiji stereomicroscope, my multimode trans-illuminator, and the 2X and 4X paired objectives. The same specimens were then examined with my modified LOMO Biolam equipped with a multimode condenser and water-immersion caps on the objectives. The girls were fascinated with watching a live copepod and a worm under the stereomicroscope using transmitted darkfield illumination.  Full article (PDF)


Tricks of the Trade | Tungsten Needle and Micro Knife Holders

Thom Hopen
The Microscope 59 (1), p 35
Excerpt: A few years back I was preparing to teach a “Gizmos and Gadgets” workshop for one of the regional forensic meetings, and I was having trouble finding inexpensive tungsten wire-needle holders to include in a lab kit for the students. Stephen Garten, a ballistic identification specialist with the ATF, who was an intern working with me at that time, found a wonderful website – www.FindingKing.com – that sells pin vises, needle holders and other handy precision tools.  Full article (PDF)


The Microscope Past: 25 Years Ago | Portable Microscope for On-Site Analysis and Counting of Asbestos Fibers

John Gustav Delly
The Microscope 59 (1), pp 37-41. Originally published in The Microscope, Vol. 34, No. 4, 1986.
Abstract: Considerable interest has been expressed in the need for a portable microscope for on-site analysis and counting of asbestos fibers. The optical and mechanical requirements for such an instrument, together with design considerations, are enumerated and explained. A prototype instrument, complete with carrying case, has been assembled and is described; possibilities for mechanical and optical variations and alternatives are discussed.  Full article (PDF)


Obituary: Maria Kuhnert-Brandstätter, 1919-2011

The Microscope 59 (1), p 43
Excerpt: Maria Kuhnert-Brandstätter, professor emerita of pharmacognosy at the University of Innsbruck, Austria, died in April, 2011. She was 91.  Full article (PDF)

Subscribe to The Microscope

Copyright © 2011 Microscope Publications, Division of McCrone Research Institute. All rights reserved.