It has been noted by many people who have had the privilege of exploring Mayan ruins that there is a stunning blue color that has been preserved amazing well for centuries. Considering the tropical jungle is quite a hostile environment, the tenacity of this “paint” is remarkable. It had been suggested that this “paint” was made by mixing indigo dye with clay, but this did not explain its special characteristics. Recent work by Miguel José-Yacamán at the National University of Mexico and colleagues has revealed what is special about this material, which is called Maya blue paint. They collected specimens in Mexico at archeologic sites known as Jaina Island and Palenque.

As the need for prefixes for 10-21 and 10-24 arose, “zepto” and “yocto” surfaced. Professor Dovichi, a leader in ultramicroanalytical techniques, jokingly suggested that these units have been named in honor of two lesser known Marx brothers. Indeed, the habits of the International Committee of Weights and Measures are mysterious, as the bastardized Scandinavian femto and atto (10-15 and 10-18) had already proved. Joke aside, the need for having units as small as 10-15 and 10-24 is a serious and dramatic development. After all, a yoctomole is less than a single molecule. It makes sense only as a probability in a quantum mechanical context. It is instructive to visualize the full range of dimensions.

A precision sectioning method is described in which the diamond blade used is specifically mounted at high tension, with the sample being fed into the blade at its inner annulus. The sawing action which results is characterized by low kerf losses, the possibility for thin slices, good surface finish, high straightness, high reproducibility and low damage. Applications which benefit from the method are mentioned, namely in the sample preparation of semiconductor, geological, composite, hard tissue and polymeric samples, as well as most non-biological samples for many areas of microscopy.

Over the past 20 years great improvements have been made in the techniques available for doing 3D fluorescent microscopy on living cells. The first approach, generally referred to as image deconvolution, treats the stack of 2D widefield (WF) image data as merely the sum of a number of discrete point-spread functions (PSF) and uses the computer to find the array of emitters'that, when blurred by the PSF, best fits the stored data. If the PSF is known, only presence of statistical and electronic noise in the data, prevents this best-fit set of emitters from being a perfect image of the dye distribution in the specimen. The crucial role played by noise can be appreciated by comparing images from the Hubbell space telescope in its original condition, even after deconvolution, with images taken after the optics had been repaired.

Molecular microspectroscopy is the application of infrared or Raman spectrascopy, combined with light microscopy, for chemical analysis on the microscopic scale. For over a decade infrared microspectroscopy (ISM) has been an expanding technology both scientifically and commercially. Micro- Raman spectroscopy has a long history of scientific accomplishments with limited commercial success. Both of these techniques give spectral data that can be related to the bonding, crystalline state, isotopic content and molecular orientation of a material, but not its elemental composition.

Specimen support grids are now almost universally 3.05 mm in diameter, except for a few high resolution stages and some very old instruments. They are available in a vast range of materials and designs. One catalogue lists 86 types in a total of 10 materials. The reason for this proliferation is to enable one to control the following:

1. (a) the amount of support the specimen needs (unsupported areas range from 20 pm to 1 mm in extent);

2. (b) the material of the grid, so that it neither interferes with X-ray analysis nor reacts with the specimen;

3. (c) the labeling of specific regions of a specimen (many grids have identification marks for relocation of interesting fields).

The cheapest most widely used supports are copper grids at a spacing of 100 bars in"1. Most grids have a shiny side and a dull side. Opinions differ as to the best side on which to mount the specimen but if a consistent practice is adopted it is always known which way up in the microscope the specimen was mounted.

LaserJets, like many other printers, print in lines per inch (Ipi). The lines represent in digital image printing lines of pixels. If the pixels are printed squarely than each square area (of a width equal to that of the actual line width) must be printed with a desired amount of ink variations in order to generate the gray levels (see John Russ’ book for a nice illustration on how this is done in a LaserJet). LaserJets and Inkjets use dots as the smallest printed entity.