Many people dread the visit to their dentist when they have their teeth drilled, but how long has this been going on? The most ancient evidence to date was recently described by Alfredo Coppa, Luca Bondioli, Andrea Cucian, David Frayer, Catherine Jarrige, Jean-François Jarrige, Guivron Quivron, Massimo Rossi, Massimo Vidale, and Roberto Macchiarelli and microscopy provided the convincing proof. The specimens were recovered from Mehrgarh, Pakistan, an area known to be occupied by farmers as long as 9,000 years ago. They identified four females, two males, and three individuals of undetermined gender who had a total of eleven drilled permanent teeth, all from adults. No drilled teeth from children were found. Four of the teeth were from the maxilla and seven from the mandible. All the drilling had been in the first or second molars. This led Coppa et al. to conclude that the drilling was not done for decorative purposes because on these teeth the holes, with or without decorative material inserted into them, would have been hardly visible.

On April 14, 1912, the RMS Titanic collided with an iceberg and sank in the North Atlantic, approximately 400 miles southeast of Newfoundland. Despite her double-bottom construction and series of water-tight compartments, the luxurious passenger liner, deemed ‘unsinkable’ by the popular press, sank in only two hours and 40 minutes, taking 1523 lives with her. As the largest man-made moving object of her time, the construction of the RMS Titanic was a technological feat, yet her sinking comprised one of the most famous disasters of the twentieth century. A colossal tragedy, the sinking has been shrouded in mystery ever since, and has led to unending speculation concerning the details of that fateful evening.

The phase-contrast imaging of atomic lattices has now become commonplace for both Transmission Electron Microscopes (TEM) and Scanning Transmission Electron Microscopes (STEMs). Recently, however, bright-field STEM images of multi-wall carbon nanotubes (MWCNTs) recorded from an ultra-high resolution (UHR) in-lens field-emission scanning electron microscope (FE-SEM) operating at 30keV have also demonstrated lattice fringe resolution. One example of such an image containing multiple examples of fringe detail is shown in figure 1. The carbon lattice fringes were analyzed and their origin confirmed by the application of the FFT algorithms in the SMART image analysis program. The resulting power spectrum after thresholding to remove background noise (Figure 2) confirms that phase detail in the image extends down to about 5 Angstroms (0.5nm) and that well defined diffraction spots corresponding to a spacing of 3.4 Angstroms (0.34nm) generated by the (002) basal plane spacing of the graphite lattice are present.

The ambition to produce a functional miniature microscope suitable for tropical disease diagnostics in developing countries has exercised the ingenuity of many talented designers over the last 75 years. In the early 1930's the late Dr John McArthur produced the first prototype of his pioneering folded optic design and this portable gem measured a mere 102 x 63 x 51 mm, yet was able to deliver everything which would be expected from a conventional bench microscope of similar optical specification (see Fig. 1A).

To achieve this high degree of miniaturization McArthur employed a folded optical prismatic system: light entered from above the microscope via a mirror and then passed through a small condenser to the specimen, a revolutionary concept at that time. The objectives were arranged below the specimen and the image was reflected by two prisms to the eyepiece.

The highly structured arthropod cuticle is often adorned with dense hairs that conceal the underlying landscape. Thus, to examine the structures and patterns on the cuticle the overlying hairs must be removed with minimal damage to the cuticle itself. Different methods can be employed to eliminate hairs but the difficulty of this task is compounded by the small size and fragility of the exoskeleton to which the hairs are attached. If the hairs are removed using razor blades or scissors, not only is the debris from the cut hairs and the stubble from the remainder of the shaft left behind, but the cuticle is often broken in the course of gripping the exoskeleton. We developed a unique technique that cleanly removes hairs without leaving debris or damaging the structure. This technique has been successfully used to examine the cuticular surfaces of arthropods of varying sizes including spiders, bees, beetles and moths.

DualBeam instruments that combine the imaging capability of scanning electron microscopy (SEM) with the cutting and deposition capability of a focused ion beam (FIB) provide biologists with a powerful tool for investigating three-dimensional structure with nanoscale (1 nm-100 nm) resolution. Ever since Van Leeuwenhoek used the first microscope to describe bacteria more than 300 years ago, microscopy has played a central role in scientists' efforts to understand biological systems. Light microscopy is generally limited to a useful resolution of about a micrometer. More recently the use of confocal and electron microscopy has enabled investigations at higher resolution. Used with fluorescent markers, confocal microscopy can detect and localize molecular scale features, but its imaging resolution is still limited. SEM is capable of nanometer resolution, but is limited to the near surface region of the sample.

Microfluidic devices, with their ability to manipulate and analyze nanoliter volumes of chemicals and other fluids, have attracted great interest across a broad range of research and industrial applications. Corporate and academic laboratories around the world are deeply engaged in developing manufacturing technologies for these devices, hoping to create the same kind of benefits and value that accrued from the miniaturization and large scale integration of electronic devices. The flexibility and programmability of direct laser ablation make it attractive as a fabrication technology, but many other aspects of its performance remain to be understood and characterized. Advanced confocal microscopy, which provides fast, high-resolution, threedimensional visualization and measurement of micrometer scale structure, is ideally suited to this characterization task.

It wasn't too long ago that making the decision where to locate your scanning probe microscope was a simple one put it in the basement where the ambient vibration was minimized. But recently, with nanotechnology applications growing exponentially, scientists and engineers are putting their equipment in a multitude of locations where vibration noise is significantly high. Scanning probe microscopes, interferometers and stylus profilers are being sited in locations that pose a serious challenge to vibration isolation.

Additionally, in an effort to keep their nano-equipment costs as low as possible by cutting out the peripherals, many academics and industries are not adequately providing for vibration isolation on their ultra-sensitive nano-equipment that they are putting into their facilities.

Lack of contrast is a common problem encountered when doing TEM of cultured cells, especially of membranes. Using ferrocyanide as a post-fixative can greatly improve membrane fixation and staining. This protocol has been used to study Caco-2 cells grown on PET membranes (the “Caco model”). Caco-2 is a colon cancer cell line that differentiates upon reaching confluency. This allows permeability studies on a cell model, which is reasonably similar to the human intestine.

Basically, the protocol is classical, the only peculiarity consisting in including ferrocyanide in post-fixation. I describe how I prepare and embed the membrane in order to obtain transverse sections of a cell monolayer because I find this is the only way to obtain regular sections with the cells sticking to the membrane (otherwise the ultrathin section splits between the cell and membrane).

Backscatter Kikuchi Diffraction (BKD) from crystalline solids has been known since 1928. But only during the last decade, when sufficiently sensitive cameras, fast PCs and high-performance SEMs have been available, has this technique been developed into an invaluable tool for materials' science and geology. BKD is also known as “Backscatter Electron Diffraction” (EBSD) if referred to the commercial trademarked systems OXFORD/HKL “Channel” or EDAX-TSL “OIM”. Crystal Orientation Measurement/ Mapping (COM), without user intervention, is performed in an SEM by digitally scanning the beam spot across the specimen, acquiring and transferring one Backscatter Kikuchi Pattern (BKP) after another into the computer, indexing it, and calculating the crystal orientation of the grain under the beam spot. The sample is typically tilted by 70° towards a phosphor screen for pattern collection. Spatial resolution is in the range of <0.05 μm and accuracy is better than 0.5°.

One of the most important tasks of microscopy is to provide information about structures in their natural state. Since most life science microscopy procedures require fixation, dehydration, drying, and sectioning, diverse artefacts are unavoidable. It is also possible to dehydrate the water content of a specimen by freeze-drying. However, even relatively stable surface structures are changed during such treatments. Methods of liquid substitution and freezing-substitution show good results for biological specimens with a waxy solid coverage (Ensikat and Barthlott, 1993) and soft specimens in a mechanically deformed state (Gorb et al., 2000).

However, all these methods have certain restrictions for some types of specimens. For example, there are numerous biological surfaces covered with secretory fluids. Some specimens bear solid waxy coverings, which can be partly dissolved and washed out in organic solvents, such as ethanol, acetone, or propylenoxide. Often one would like to visualise dynamic processes (growth, deformation, or crystallisation) under environmental conditions, but at the high resolution in the SEM.

Nanoparticles (1-10 nm in diameter) are particularly susceptible to disorder, amorphization, deformation and/or dissolution upon ion irradiation as compared to their bulk counterparts, which is a consequence of the enhanced surface area to volume ratio of the former (structural disorder is often observed to be preferentially located at the surface). Synchrotron-radiation-based analytical techniques are ideally suited for the elucidation of structural perturbations as compared to the bulk material. Such techniques are commonly complemented by cross-sectional transmission electron microscopy (XTEM). XTEM offers invaluable information with respect to shape and morphology of the nanoparticles.

For the present work, Cu nanoparticles were synthesized within a 2 μm amorphous SiO2 matrix on a 520 μm Si support by ion implantation and thermal annealing following a procedure described elsewhere. In order to study the influence that ion irradiation has on the nanoparticles, the sample was then irradiated with 1x1015 ions / cm2 high-energy (5 MeV) Sn+ ions.