Would you believe it might be possible to build organs using an ink-jet printer? In a remarkable pair of articles, Thomas Boland and his collaborators describe a modified printer that promises to be abie to do exactly that.

The first article of this pair describes the software and hardware to arrange cells in two dimensions, just as a printer arranges droplets of ink on a fiat piece of paper. The software that normally controls the position of a drop of ink is modified to position a drop containing one or two cells in suspension onto a substrate.

Since early times, the collective understanding of our microscopic universe has been directly tied to the quality of our microscopies. This has been true from the advent of light microscopes through to modern electron microscopes. Indeed, if one is to work on a given scale, one must be able to “see” at that scale. At the beginning of the 21st century, human inquiry is focused on the atomic scale.

The first time you stand on the deck of a research icebreaker as it crunches its way through the Antarctic pack Ice, you're surprised at how many colors there are. Ice covers the sea everywhere you look; perhaps here and there an occasional gargantuan iceberg rises majestically above the pack. Everything between you and all three hundred and sixty degrees of the horizon is gently undulating under brilliant sunshine in unison with the sea swell. It's a January mid afternoon, the heart of the southern summer, and you're bundled up against the biting cold. You can't stop smillng.

A new class of silicon multi-cathode detector (SMCD) has been developed for microanaiysis spectrometry applications. The detector has excellent energy resolution (< 150 eV FWHM) and high count rate capability (>1 Mcps). An energy resolution of 143 eV FWHM at 5.9 keV was measured with the SMCD at 6 μs peaking time.

Combinatorial and high-throughput (C&HT) approaches accelerate research by addressing multiple experimental parameters in a parallel or otherwise highly efficient fashion. First used by the pharmaceutical industry for product discovery, the C&HT paradigm is being extended to the study of complex materials systems that require measurements of properties and phenomena over a huge number of conditions. As with traditional materials science, microscopy and imaging of morphology are essential for C&HT materials research.

The terrorist attack and collapse of two towers of the World Trade Center (WTC) in New York City on September 11, 2001 generated tremendous clouds of dust that settled over a wide area. Concern over the potential health effects of breathing this dust made it imperative that the WTC dust be characterized as completely as possible. As part of this characterization, a microscopical examination using several types of microscopes provided key data on the components of the dust. The WTC dust sample that is the primary focus of this report was collected by F.C. Ewing from an outdoor window ledge at 33 Maiden Lane, New York City, NY on October 7, 2001.

Soil structure influences water supply to plant roots, aeration, water infiltration rates, suitability of soil medium for seed germination and growth, growth of plant roots, drainage, evaporation, mechanical strength, and workability (Dexter 1988). Adequate description of soil structure for cultivation, engineering, or remediation is typically done by light microscopy and transmission electron microscopy. Literature exists in numerous sources for preparation of soils for microscopy, but often preparation steps are left out due to the shortening of Methods Sections in journal articles to conserve print space. I present here, protocols I've used for preparation of tropical soils (Oxisols) for microscopy.

Cast irons belong to a family of iron-carbon (Fe - C) alloys with free carbon in the form of graphite, a very soft constituent of iron microstructures, that improves machinability and damping properties of castings, or combined carbon, in the form of cementite, that improves wear resistance. Graphitic cast irons include grey iron, compacted iron, malleable iron, and ductile iron, Cementite irons include white cast iron and alloy cast irons. Solidification of graphite directly from molten metal takes place between 1145°C (2093 °F) and 1152 °C (2105 °F), according to the Fe-C equilibrium diagram. The above considerations regard only pure Fe - C alloys.

Microanalysis using an EDS on an SEM are sometimes asked whether two samples are of different composition, or if different regions in the same sample vary in composition, A best educated guess may be that differences of a few percent can be distinguished under optimized conditions that include favorable data collection times and count rates, stable instrument operation, and well prepared samples and standards that remain free of contamination. Another frequently asked question is whether it is possible to detect a given amount of a particular element in a sample.

In the world of fluorescent imaging, the need to colorize grayscale images can be an everyday task. Yet, when all too many of these colorized images go to publication, the results appear to contain undifferentiated blobs of a saturated color, rather than images that contain gradations of color.

While very small objects need to be as bright as possible in order to make these objects apparent (e.g. bacteria under low magnification), and while too many push the gain on photomultiplier tubes in order to top grayscale values off at 255 (on an 8-bit range) in order to show unquestionable colocalization, only the former can be defended on the basis of revealing lost features.

Holey carbon films mounted on standard EM grids are routinely used as specimen supports in electron cryo-microscopy, Adroplet of the sample containing, for example, a suspension of virus particles or protein molecules, is applied to the grid, blotted to a thin layer and rapidly frozen. The particles are then imaged where the liquid spans the holes, without interference from an underlying carbon support film. Many recipes for holey films have been presented in the literature, generaiiy employing some method of forming bubbles in a layer of solvent in which a material is dissolved that then forms a discontinuous layer as the solvent evaporates.

This topic appeared on the MSA list server In December 2002 and January 2003. While cleaning my gauge tube recently, I documented the steps. In this article I describe cleaning a Varian 524-2 gauge tube. There are a number of other cold cathode and penning style gauge tubes on the market, Edwards CP-25 (old penning), CVC GPH-001A(old cold cathode), Pfeiffer IRK 250 (new cold cathode) to name a few. The cleaning steps are very similar. Consult the instructions that came with the gauge tube or visit the vendor's websites.

Multiple specimen holders make it possible to examine several (up to 7) specimens by SEM without the need to vent the microscope, replace the specimen, and evacuate the microscope again. Using such a holder in a Philips XL-30 ESEM frequently showed zigzagged outlines of bacteria obtained at magnifications higher than 10,000x. The zigzag outlines were not associated with charging artifacts as the filter edges were painted with a silver-based cement prior to gold coating. The severity of the zigzag lines varied from day to day. Sometimes they were barely noticeable whereas at other times they developed during a half-day session.