The Microscope - Volume 69, Fourth Quarter 2022
On the cover:
The reddish-orange particles are etched garnet from the Morrison Formation in Santa Fe, New Mexico; plane polarized light. See How We See: The Light Microscope, Visual Routines, and the Microscopist, page 147. (Photomicrograph courtesy of Russ Crutcher/Microlab Northwest)
Editorial | Polymorphism and “Universal Seeding,” or Disappearing Polymorphs
Gary J. Laughlin
The Microscope 69:4, p ii, 2022
Excerpt: Any chemical compound showing polymorphism can crystallize with different internal lattices that will give correspondingly different external crystal morphologies, different optical crystallographic properties, and different physical properties. Ludwig and Adelheid Kofler and their successors in Innsbruck, Austria, along with Walter C. McCrone and his successors in the U.S., expounded the topic of polymorphism, especially as it was investigated with the polarized light microscope equipped with a hot stage.
How We See: The Light Microscope, Visual Routines, and the Microscopist
Russ Crutcher and Heidie Crutcher
The Microscope 69:4, pp 147 – 159, 2022
Abstract: This paper addresses three critical aspects of analysis using the light microscope: 1) the human visual system, 2) the versatility of the light microscope, and 3) the importance of training and visual routines. The image of a particle produced by the light microscope is only an image, but it reveals important information about the shape, chemistry, and ontology of the particle. Changing the configuration of the microscope alters the image and provides additional information about the particle itself. While other analytical equipment generates graphs, tables, and charts, the microscope generates an image in the eye and brain of the microscopist. The microscopist is the detector for the microscope and the analyst of the signal generated by the detector. This is a two-part process. A fitting analogy is the concept of visual routines as used in the fields of computer vision and artificial intelligence. It refers to program modules that take raw images and process them into something intelligible. The term visual routines is being used here in this paper to address the relationship between the image generated by the retina, mental manipulation of the image, and by a specific configuration of the microscope. The microscopist needs to be trained to appreciate the analytical significance of different images of an object as the illumination system is changed. The addition of two polarizing filters to a transmitted brightfield image is one example. Understanding the light microscope as a sophisticated optical bench is part of the approach. Polarized light microscopy (PLM) and phase contrast microscopy (PCM) are limiting configurations but useful as two tools in the microscopist’s toolbox. There are many more transmitted light systems before even considering reflected light systems. An optimized light microscope is equipped with both a transmitted and reflected light system.
Area Percentage Charts to Aid Visual Estimation of Asbestos Concentration in Bulk Asbestos Samples
The Microscope 69:4, pp 160 – 162, 2022
Abstract: Among the methods of quantifying asbestos contents in bulk asbestos samples, the most frequently used is the visual estimation. This paper presents a series of reference area percentage charts, featuring fibrous morphology to imitate asbestos fibers in a non-fibrous matrix. These charts can be used in the training of bulk asbestos analysts to better perform the calibrated visual estimation (CVE) of the area percentage of asbestos fibers in bulk samples.
Critical Focus | Germ Versus Germ
Brian J. Ford
The Microscope 69:4, p 163 – 174, 2022
Excerpt: Bacteriophages — viruses that destroy bacteria — were introduced 100 years ago and used in communist countries, yet the West has not realized their potential to cure infections.
It’s July 2022, and there’s much excitement in the newsroom at CNN. An astonishing new miracle cure is being announced. Steffanie Strathdee was gently cradling the hand of her husband Tom Patterson in the hospital. He was close to death from a bacterial infection contracted on a cruise to Egypt. Antibiotics had proved useless, when she dramatically decided to try something revolutionary. She contacted Texas A&M University, whom she knew had been working on the treatment of recalcitrant infections using viruses. The viruses that attack and destroy bacteria are bacteriophages — phages in daily parlance, pronounced to rhyme with “Taj” in Taj Mahal. It was with phage viruses that the Texas team proposed treatment, instead of drugs. Within three weeks her husband was cured.
New Microcrystal Tests for Controlled Drugs, Diverted Pharmaceuticals, and Bath Salts (Synthetic Cathinones): Tramadol and Zolpidem
Sebastian B. Sparenga, Gary J. Laughlin, Meggan B. King, and Dean Golemis
The Microscope 69:4, pp 175 – 187, 2022
Excerpt: The Microscope is publishing selected monographs from McCrone Research Institute’s recently completed research, New Microcrystal Tests for Controlled Drugs, Diverted Pharmaceuticals, and Bath Salts (Synthetic Cathinones), which contains newly developed microcrystal tests and reagents with 9 additional drugs: alprazolam, butylone, mephedrone, methylone, MDPV, 4-MEC, alpha-PVP, tramadol, and zolpidem. This issue includes the last four monographs for the following drugs/reagents:
• Tramadol/gold bromide with acetic acid and sulphuric acid
• Tramadol/gold bromide with hydrochloric acid
• Zolpidem/gold chloride with hydrochloric acid
• Zolpidem/platinum bromide with sulfuric acid
Author and Subject Indexes: Volume 69, 2022
The Microscope 69:4, pp 188 – 191, 2022
Afterimage | “Nitron” Test for Nitrates
The Microscope 69:4, p 192, 2022
Microcrystal test for the detection of nitrates. These highly birefringent acicular needles are direct addition products of nitrate anions together with diphenylendanilodihydrotriazol, also known as the reagent “nitron.” This photomicrograph, in crossed polars, was taken by Andrew Bowen in preparation for Microscopy of Explosives courses taught at McCrone Research Institute, circa 2002.
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