This year marks the 100th anniversary of the discovery of X-ray diffraction and the 85th anniversary of electron diffraction (see Microscopy Pioneers). For most of the time since their introduction, microscopists have known these two techniques as the primary phase identification methods used in conjunction with various microscopies. However, these two diffraction methods also have played enormous roles in understanding the structure of matter, as well as the nature of both X rays and electrons.

About 40,000 to 30,000 years ago, modern humans out-competed Neanderthals, and the Neanderthals became extinct. Some recent theories have speculated that Neanderthals had an inferior diet (predominately meat) that put them at a disadvantage. Evidence for plant foods is rare at sites occupied by Neanderthals, but this could be due to vagaries of preservation and insufficient attention to plant remains. In an ingenious study, Amanda Henry, Alison Brooks, and Dolores Piperno used microscopy to demonstrate that plants and cooked foods are present in dental calculus (the stuff the dental hygienist scrapes off your teeth) on the teeth of Neanderthals.

Electron diffraction in both SEM and TEM provides a contrast mechanism for imaging defects as well as a means for quantifying elastic strain. Electron backscatter diffraction (EBSD) is the commercially established method for SEM-based diffraction analysis. In EBSD, Kikuchi patterns are acquired by a charge-coupled device (CCD) camera and indexed using commercial software. Phase and crystallographic orientation information can be extracted from these Kikuchi patterns, and researchers have developed cross-correlation methods to measure strain as well.

Nanotechnology represents a major area for research and development and has already led to the introduction of hundreds of products that incorporate nanotechnology-based materials, components, or methods. It is an area of significant investment and economic development globally. NanoInk, Inc. designs and develops instrument systems used for nanotechnology research, education, and manufacturing. Our initial product was built to support sophisticated research programs in academic and government labs. It was based on a complex instrument that was difficult to learn and use: the atomic force microscope (AFM). In order to make our technology accessible and useful to a broader range of potential customers and markets, NanoInk developed a new instrument platform, NLP 2000, that is simpler to learn and operate by users who are not university-trained PhDs. This article will discuss several of the challenges, design goals, and approaches taken in developing this instrument platform.

Gatan Digital Micrograph (DM) software is considered an industry standard among microscopists. The offline DM application is freely available from Gatan. Unfortunately, DM software has been designed to run only on Microsoft Windows operating systems, thus distancing the microscopy community from popular Unix-based systems, such as Linux or Mac OSX. An ad hoc solution to this problem has required a virtualized Windows operating system running on top of the user's native operating system. This is not only slow, having to emulate each processor instruction, but also requires installation and licensing of Windows and the virtualization software. However, with the aid of open-source resources, it is possible to run DM natively on Linux and Mac OSX (Figure 1). This article was written as a guide with easy-to-follow installation instructions to liberate users from the Windows emulation pidgeonhole and enable them to freely analyze data on Unix-based systems.

Sample preparation is a critical step in scanning electron microscopy (SEM) imaging. This is especially true for biological samples because of charge build-up and sensitivity to vacuum and electron beam damage. In terms of ultrastructure imaging, a variety of advancements in detectors and approaches have improved biological imaging such that fewer steps are required for sample preparation. However, the conventional approach incorporating osmium tetroxide fixing, ethanol dehydrating, critical-point drying, and coating still finds useful application. This paper evaluates three biological sample-preparation methodologies for imaging the ultrastructure of immature porcine retina. The three preparation methods examined are critical-point drying (CPD), hexamethyldisilazane (HMDS) dehydration, and direct imaging by environmental scanning electron microscopy (ESEM). Preparation methodologies were evaluated based on resulting image quality and reduced potential for artifacts.

Archaeologists have found that the elements present in the pigments used on Ancestral Puebloan black-on-white painted pottery are an important descriptive attribute. They typically describe the pigments used to produce these painted designs as either carbon-based (containing primarily organic compounds) or mineral-based (containing primarily iron compounds), although in some cases these pigments are combined or “mixed”.

This year marks the eighty-fifth anniversary of the discovery of electron diffraction. In addition to its important role in materials characterization, electron diffraction contributed substantially to several Nobel Prizes, to foundations of quantum mechanics, and to the development of the theory of covalent bonding in organic chemistry. What follows is a personal narrative describing the development of this technique.

Polymers are organic materials, and most of the preparation methods for transmission electron microscopy (TEM) are much the same as for biological specimens. Bulk samples are cut in the ultramicrotome, and latex particles are dropped onto a Formvar-coated grid. However, the staining possibilities of polymers are limited. Polymers mainly consist of saturated hydrocarbon, and unlike biomaterial there are few reactive groups for staining. This has two consequences for the microscopist: it is difficult to obtain contrast, and the sample is very beam-sensitive. Biological samples are also organic material and sensitive to the beam, but the staining process converts them into materials that are usually stable to the beam.

Selected postings to the Microscopy Listserver from November 1, 2011 to January 1, 2012. Complete listings and subscription information can be obtained at http://www.microscopy.com. Postings may have been edited to conserve space or for clarity.

Following is a list of microscopy related meetings and courses. The editors would greatly appreciate input to this list via the electronic submission form under “events/other microscopy events” at the MSA webpage: www.microscopy.org. We will gladly add hypertext links to the notice on the web and insert a listing of the meeting in the next issue.

Our Office of the Vice President for Research has lost so much money investing in real estate that our operations budget has been reduced dramatically. We are looking into alternative means to supplement our revenue stream. Someone suggested taking in outside work. Can you suggest alternatives?