NetNotes


they are trying to do, how best to do it, and on which instrument. 2. Training (for TEM) is usually 3 × 3 hr sessions either with a technical staff member or with one of our competent grad students. Users are taught from a standardized manual, which shows step by step procedures with lots of pictures. Users are encouraged to annotate their own copy of the manual. 3. Aſter training users are given 1–3 supervised solo sessions, where tech staff get them started and drop in frequently to assist with any queries. 4. Once the user is confident running the machine solo they are assessed. Tis is two part process. Te first part is a 40 question multiple choice quiz, covering basic theory, instrument operation, safety etc which is covered during training. Nobody fails the quiz—we use it as a safety net to fill in gaps in users’ knowledge. Te second part is an assessment, where the user goes through setting up, operating, and shutting down the instrument—it's open book so they can refer to the manual. Tis is supervised by technical staff to ensure quality control. Users need to be able to do all the basics without undue hesitation and without harming (or nearly harming) the microscope. 5. Users who fail the test are given more training. In some cases lots more, until they get it right. 6. Users on instruments can always get immediate help from one of our technical staff by calling our Duty Microscopist number. Tis avoids having users wander corridors in search of staff, and avoids them getting bored and trying to fix things themselves—which is usually where things go bad. Despite all the above, trained users stuff things up occasionally, usually through carelessness. Such users are retrained in whatever they stuffed up and watched carefully thereaſter. We avoid tearing strips off users who do bad things as it discourages them from asking for help or owning up to mistakes. We strongly encourage "if in doubt—ask." Dave Mitchell drg.mitchell@sydney.edu.au Tue Mar 1


History:


early EM and ultramicrotomy I recently read this article about Ernst Ruska and thought


of sharing it with the list, many of you may have already read this but it’s truly a fascinating read. http://www.mpg.de/english/ illustrationsDocumentation/multimedia/mpResearch/2006/heft03/ Electron_Microscopy_Ernst_Ruska.pdf. Neeraj V. Gohad neerajg@ clemson.edu Fri Jan 7 It is very interesting. It doesn’t mention why Ruska could not have


received the Nobel Prize way back in the 50s when the microscope was new. Te concept was patented by somebody else, a Mr. Rudenberg, from the Siemens Company, based on a visit to Ruska’s laboratory. It has all been written about by Ruska in his book. Carol Heckman heckman@bgsu.edu Sun Jan 09 As the article describes, the early version of the instrument


could only reach modest resolutions and we have to remember that the thermal advancement ultramicrotome by Porter and Bloom was reported in 1953. We know now what the combination of TEM and ultramicrotome did for biology and other fields, and gradually many crucial discoveries were made using the TEM which eventually could attain atomic resolutions. Tis is somewhat similar to discovery of laser, many of the key people who worked on the laser during its conception were awarded the Nobel prize later. Luckily the TEM didn’t go through the lawsuits and patent battles that the laser did. Tis may be true of our times too, we have yet to fully grasp the potential of recent advances in super-resolution optical imaging. Neeraj V. Gohad neerajg@clemson.edu Wed Jan 12 Te Porter-Blum microtome was mechanical advance. Simple,


reliable, unbreakable. Caroline Schooley schooley@mcn.org Wed Jan 12


My mistake, I meant mechanical, Porter-Blum MTI was indeed mechanical, but you get the point. neerajg@clemson.edu Wed Jan 12


66


I know at least 2 old microscopists who made glass knifes


by breaking window glass—one of them here at CMU. He went to construction sites to get the broken windows. I’m running down the reference and (I hope) an image, but one of the early tries at ultramicrotomy was sticking razor blades on a centrifuge rotor, then mount the sections on the tub, close the lid and turn on the centrifuge. Te sections where then picked up from inside the tub, having been flung willy-nilly around the inside. Te image is used in the microtomy lecture to convince the students thin sectioning could be a lot worse than they think it is. Phil Oshel oshel1pe@cmich.edu Tu Jan 20 Indeed. We are in a building that was oſten broken into. Years


ago, I made it my business to collect the old door panes—they were a tinted glass, about 1/4′′ thick, and had just the right temper to make excellent knives. Joel B. Sheffield joelsheffield@gmail.com Tu Jan 20 I just remembered seeing a print ad from some science journal


published the 40s or 50s (before my time!) for an early ultramicrotome. It was a high speed motor spinning some type of blade. Te concept was that the block was advanced into this buzzsaw and you were supposed to catch the sections flying off. At the time I think the view was that ultrathins could only be cut at high speed. Te real kicker was the ad mentioned the motor was also suitable for use in centrifuges. Crazy. Tom Phillips phillipst@missouri.edu Tu Jan 20 Sorry for the delay in response to this topic, but due to an error


on my on my part my previous communication went astray. For those who may be interested in the history of ultramicrotomy I do have a copy of an article in PDF form which traces the development of the ultramicrotome from “wedge” sections in the late thirties where the thin end of the wedge was (hopefully) transparent to electrons, through the high speed era (actually up to 57000 rpm), overcoming embedding limitations and finally discussing the first generation of commercial instruments. Please contact me on terry.cooper@ btinternet.com and I can attach the missive, Terry Cooper terry. cooper@btinternet.com Wed Feb 2 Fascinating article. Some of my recollections (possibly with


some inaccuracies but the best I can recollect) involve Fernandez- Moran who is credited with developing the first diamond knives for use with ultra-microtomes as well as a cryo ultra-microtome and a number of other interesting developments. I worked for Fernandez- Moran at the U. of Chicago for a few years starting in 1963. Tis was aſter he was forced to leave Venezuela and then did a short stay at MIT before being recruited by U. of C. He had a microtome, presumably of his design, that only he used on rare occasion. Almost all the imaging done in the lab was with negatively stained samples. He, of course, had his diamond knives. Te technique to make them was perfected at the lab for neurological research that he built in Venezuela. (He was forced to leave Venezuela when the government was taken over by a military coup and he was on the wrong side, but that’s another story.) He had a workshop there with his diamond cutters, etc. Aſter developing the knives, he sent them out to the leading investigators of the day to get them to try them so that they would then buy them. Dupont picked up on the idea and also began making them for sale. Moran had patented the process so was able to sue Dupont and did win. I believe he later agreed to give them rights to make and market the knives. Moran’s lab at Chicago was quite a place. It was a semi-clean room lab in the basement of the Research Institute. Te floors were raised so that all the water and vacuum lines for the microscopes were underneath with mechanical pumps and water recirculators a long ways away from the microscopes. He had 3 Seimens 1 and 1A TEMS on vibration mounts with the raised floor cut around the microscope bases so that moving a chair would not affect the TEM stability. A motor generator located in


www.microscopy-today.com • 2011 May


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