Proteins in biologic membranes perform a large variety of essential functions. The fact that about one third of all genes code for membrane proteins, and that the majority of drugs target these proteins, attest to that fact. However, until now, proteins have been studied under artificial conditions, such as after being crystallized, frozen, or adsorbed to a substrate. Rui Pedro Gonçalves, Guillaume Agnus, Pierre Sens, Christine Houssin, Bernard Bartenlian, and Simon Scheuring have devised a novel setup with the atomic force microscope (AFM) to allow proteins to be probed while they are in unsupported membranes. Their method is similar in principle to methods where a small area of a membrane is sampled, such as when a piece of membrane is examined by patch clamping. The difference is that instead of attaching a membrane to the end of a pipette, it is spread across a piece of perforated Si(001).

This mission flew by Comet 81P/Wild 2 where it collected more than 10,000 particles, ranging from tens of nanometers to hundreds of microns, and carried them to Earth for a safe landing in the Utah desert on January 15, 2006. So what? The answer depends on one's interest. Technically, it was a perfect DISCOVERY-class mission from launch to soft-landing (Figure 1). Scientifically, it delivered some of the 4.6 Gyrsold particles that went into making the planets of our solar system and for the first time ever we have samples from a known comet.

Many challenges lie ahead. First, the grains must be extracted from the capture cells, and prepared for mineralogical and chemical analyses, including stable isotopes and organic phases. Second, the NASA/JSC Stardust Curatorial Facility has to prepare and keep track of each sample allocation. Third, data collected in many laboratories around the globe will need to be synchronized for publication.

Salary Surveys continue to create considerable interest. We still get requests for our 2004 salary survey results to this day. The current survey parallels the format of the 2004 survey, asking the identical questions to facilitate comparisons. The 2007 survey was sent by email to those Microscopy Today subscribers in the United States for whom we had email addresses. Respondents completed the survey on the internet within an eight-day window in mid-May 2007. We needed 350 respondents in order to have results accurate to ± 3%; we had 674 respondents. The survey was anonymous. Thank you to all that participated.

Open trade policies have influenced trends in global economic growth. Though difficult to account for all of the effects of this trend, a higher standard of living for previously distressed workers is measurable. This is in part due to acess to previously unavailable technologies. The effects of global economic growth extend further. In many countries, consumers enjoy unparalleled selection of high quality, low cost goods. The environmental impact of global growth is being studied in many ways. One area of study involves analysis and monitoring of product raw materials that many times are not in compliance with environmental regulations of the end user country. Raw material procurement and formulation by manufacturers presents a challenge to the environmental microscopist on several levels. The industrial use of sepiolite and some light microscopy basics of sepiolite is discussed here. Subsequent papers will explore this issue in greater detail as it relates to fibrous mineral analytical choices and techniques available to the environmental microscopist.

Since becoming popular more than a decade ago, low vacuum scanning electron microscopes (SEM) have continued to evolve. The latest systems offer uncompromised performance over an unprecedented range of sample chamber vacuum conditions. Instruments are now available that provide near-nanometer resolution in all vacuum modes and the ability to operate at pressures as high as 4000 Pascals (~30 Torr). Low vacuum operation eliminates much of the sample preparation required for conventional (high vacuum) SEM. Insulating samples can be imaged without conductive coatings. Wet, dirty, outgassing samples can be examined without drying and fixing. Systems can also be configured with a wide range of ancillary capabilities for imaging, analysis, and sample manipulation, including advanced secondary, backscattered, and transmitted electron detection, X-ray spectrometry, electron backscatter diffraction, and focused ion beam (FIB) manipulation. The current generation of systems combine speed, flexibility, repeatability, and ease of use, making them the ideal solution for any laboratory that must satisfy a wide range of imaging and analytical demands.

Transparent specimens are usually examined by dark field, phase contrast and interference contrast light microscopy. In dark field, specimens are illuminated by oblique light beams that come from the periphery of the illuminating apparatus. Therefore, some transparent objects, e.g. unstained native bacteria, are barely visible and fine structures inside them are often not visible. In phase contrast, the discernment of fine detail can be reduced by halo artifacts. The intensity of contrast, i.e. the difference in brightness between the background and specimen, is constant and not variable; it is determined by the specification of the phase ring within the phase contrast lens and dependent on the specific phase differences between the specimen and its surrounding medium. Interference contrast images are free from halo artifacts, but their contrast may be lower than in corresponding phase contrast or dark field images, especially, when transparent specimens are examined in thinlayer preparations.

To one degree or another, most materials experience some type of interaction with a large number of diverse environments. Often, such interactions impair a material's usefulness as a result of the deterioration of its mechanical properties (e.g., ductility and strength), other physical properties, or appearance. Deteriorative mechanisms are different for metals, ceramic materials, and polymers. In metals, there is actual material loss either by dissolution (corrosion) or by the formation of non-metallic scale or film (oxidation).

Everyday objects and structures are made of well known metals like aluminium, brass, bronzes, copper, titanium, zinc.

The stereomicroscope was the main tool I once used for metallurgical failure analysis. I have owned a Meiji EMT Greenough-type stereomicroscope since the late 1980's. I had not used transmitted light with the stereomicroscope until about a year ago when I completed a multimode transmitted light illuminator for my Meiji stereomicroscope. I thought this capability would be very useful for introducing the grandkids to the microscopic world, especially with live lake water organisms. My earlier article in Microscopy Today, “Rediscovery of Darkfield Dispersion Staining while Building a Universal Student Microscope,” January/February 2003, demonstrated usefulness of a dual brightfield and darkfield capability in transmitted light for viewing living organisms. I have a ½″ fiber-optic bundle light guide used in the illumination system for my modified Biolam microscope also shown in Microscopy Today, “Effects of Condenser Spherical Aberration on Image Quality,” March 2005.

Effective life cycle cost (LCC) management for electron microscope (EM) facilities at Purdue University and in other academic institutions is a complex process. Ideally, it should aim at controlling the cost of ownership of EMs while maximizing the output of the technology and utilization of resources. It could be argued that the current focus of the majority of EM facilities has been one that seeks to obtain the latest technology. However the growing sophistication of the equipment causes more indirect costs including labor, maintenance, and ancillary equipment needed to optimize the output of the base equipment. These costs can easily exceed the purchase price of the equipment over the life of the equipment.

The McCrone Group Inc. recently announced the completion of a 40,000 sq ft addition to house its new College of Microscopy. Since its founding in 1956, The McCrone Group has grown into a multi-faceted organization and now encompasses three main organizations, McCrone Associates - the analytical service and consulting firm; McCrone Microscopes & Accessories - the microscope and instrument sales group; and, the College of Microscopy - the microscopy learning center. The newly completed addition houses the first and only College of Microscopy and offers the largest array of basic and advanced modern microscopy courses and analytical instrumentation within any single educational facility worldwide. At The McCrone Group, we have more than $15 million worth of microscopes and analytical instrumentation and assembled one of the best scientific/administrative teams in the world.

Semi-thin sections don't always want to stick to glass slides, but subbing slides is usually not needed. For sections about 2 μm thick and no larger than 4 mm on a slide, this simple method works well for me:

1. 1) Clean 1x3 inch glass slides with an ethanol rinse, then air dry at room temperature or blow down with a hair dryer.

2. 2) Collect sections on a drop or two of distilled water on the slide, transferred there from the microtome with a clean fine tipped artists brush. Collect about 8-12 sections per drop.

3. 3) Warm the slide beneath the water drop from below using an alcohol lamp, fairly hot, but not to boil, of course. After drying by heating the sections stick quite well.

4. 4) Stain, usually with 0.2 μm filtered toluidine blue, again heating but gently this time, for about a minute, until stain “develops” the section.

5. 5) Rinse that stain off with distilled water from a squirt bottle, even directing the spray right onto the sections to get rid of any precipitate. Dry again gently with flame.

The heating is the trick. There should not be any need for subbing or otherwise treating slides other than cleaning them.

It can be difficult to get an even layer of metal coating when sputter coating a sample with steep sides, a rounded lower surface, or one that doesn't make complete contact with the surface of the specimen stub. It can be particularly difficult to get sputtered metal in under the sample, and so an insulating sample (like most polymers and biological specimens) may have little or no electrical path to ground. This results in charging, and increased chances of specimen heating and beam damage in the SEM.

These stub holders were made to fix that problem. A couple of metal shelf brackets, which slide into pegs and support the shelf, were modified. The brackets are small 90° angles with a hole in one face and a peg on the other face. To modify them, first the 90° angle of the bracket is bent slightly past 90°.

Resolution and pixel number is a recurring question in microscopy, especially in regards to appreciating or visualizing the image's resolution once an image is captured. For instance, what is the effect of changing a one megapixel camera for a three megapixel camera? It is important to consider nanometers (or micrometers) per pixel, which will determine the ultimate resolution available. Of course Nyquist will tell you that you can't push things to the single-pixel dimensions—a couple of pixels is more likely the limit.

It is also important to remember that raw pixel count alone is meaningless. The image formation process must be considered. The camera needs to be matched to the phosphor for optimum cost and performance.

I have found the best way to cleave [001]-oriented silicon wafers is rather different compared to GaAs or InP. The problem is that Si prefers to cleave on (111) planes rather than (110) and so one gets an angled face with the cleave, which is usually rather uneven and often doesn't run straight. This is even worse when cleaving close to an existing edge, which attracts the crack front as it propagates. Good for making low-angle cleaved specimens, but a problem otherwise. It is possible to make Si cleave on (110) by cleaving the wafer without any support.