A Special Pre-meeting Symposium/Workshop Saturday and Sunday, July 11-12, 1998
Organizer: Jim Pawley

Multiphoton excitation microscopy is the latest wrinkle in 3D light microscopy. Compared to earlier methods such as widefield deconvolution and confocal microscopy, multiphoton excitation promises a number of advantages. Chief amongst these improvements are the ability to image features far below the surface of thick, transparent specimens and to do so with up to 1000X less phototoxicity and photodamage than is produced by ÒnormalÓ confocal.

With 3D light microscopy being increasingly used to follow developments in living cells, embryos and tissues; and the recent introduction of several commercial multi-photon instruments, we can expect this field to display explosive growth in the next few years. This symposium and workshop will focus on the techniques and instrumentation needed to make this promise a reality.

The symposium program will include two full days of lectures with hands-on Workshop sessions on multiphoton instruments during the afternoons. Symposium-only students will hear lectures by industry representatives in the afternoons.

Registration Fee: $50.00 (Symposium only) or $300.00 (Symposium plus Workshop: limited to a maximum of 20 applicants)

Informal interactive question-and-answer sessions with experts in various fields of microscopy and microanalysis.

Following the success of the ÒExpertsÓ session in 1997, we plan to repeat this novel means of communicating scientific knowledge. Essentially, we shall identify hot topics and then locate one or more experts to answer questions posed from the audience. The ÒexpertÓ has no prepared material for the one hour format. Audience members choose the questions and the expert, or other members of the audience, contribute answers. Some rather extraordinary dynamics ensue.

Computational Deblurring (a.k.a deconvolution) of light microscopic images is of fundamental importance to the analysis of three-dimensional structure in biological objects. The full range of deblurring methods, including the latest advances, will be discussed and applied to as large a number of biological systems as possible. The usefulness of deblurring for images from both widefield and confocal microscopes will be emphasized and compared. This session will be coordinated with the exhibitorsÕ tutorials to the extent possible to enable hands-on learning.

Scanned Probe Microscopy (SPM) has developed into a common place microscopy and microanalytical technique. Starting with scanning tunneling microscopy (STM), the field took a rapid development trend with the development of the atomic force microscopy (AFM) and the series of scanning force microscopes. These microscopes are applicable to virtually any sample and operate in environments ranging from vacuum to liquids, opening virtually any solid material to examination by the technique. The techniques offer high spatial resolution, in some cases down to the atomic scale, and three dimensional mapping of surface topography. The various modes of AFM will be introduced, along with numerous application examples. The tutorial will conclude with some comments on the future of scanned probe microscopy, and comparisons to other more traditional microscopies.

This tutorial consists of three 45-minute presentations on tripod polishing, ultramicrotoming and ion milling. Over the past few decades, the demands of modern analytical electron microscopy have increased the need for TEM specimen preparation techniques with a minimum of misleading artifacts in terms of chemical microanalysis. At the same time, the demands of modern industrial materials (be they semiconductor, polymeric or composite in nature), call for speed, flexibility and high resolution for specimen location as well. It is the purpose of our three, interrelated presentations to review some of the developments in these classic techniques which have kept them very viable, then to describe the basic steps of the newer techniques based on mechanical preparation Ð notably tripod polishing and diamond knife sectioning. Both techniques are renowned for speed, flexibility and precision, but demand care and organization on the part of the practitioner. Finally, the very new (and rather pricey) technique of focused ion beam (or FIB) milling will be reviewed in terms of why it may still be a very economical solution to thin section preparation woes.

Silicon based nano- and microfabrication can be used to produce a variety of electrical and mechanical devices on the micrometer scale. Such devices enable a wide range of biological experiments that cannot be approached in any other way. For example, they make it possible to isolate cells and molecules from extremely small volumes (pico- to femtoliters), measure force on the scale of individual cells or molecular systems, create artificial pathways for biological molecules, develop micro-instruments for sensing and measurement in the body and creating intricate patterns to be used to study and/or control cell growth on chemically defined surfaces. The fundamentals of nanofabrication technology will be presented and its applications to diverse areas of biology and medicine will be explored. Results will be presented from the National Nanofabrication Users Network. The purpose of the tutorial is to introduce these methods to biological investigators whose projects might benefit from this advanced technology. Contributed abstracts focusing on nano- and microfabricated devices applied to biology and medicine are also encouraged. These contributions will be organized into a poster session with selected abstracts presented from the platform.

Quantitative analysis procedures using electron microbeam instruments have been refined and work quite well for a wide range of elements and sample compositions, such as Cr, Mn, Fe and Ni in stainless steels. However, as microprobe applications have become growingly complex and cover an ever-increasing range of the periodic table, many analysts have encountered elements and/or samples that Òjust donÕt analyze right.Ó Examples include elements that have very high- and low-energy characteristic x-ray lines, matrices that contain both very low Z and high Z elements, elements that migrate or volatilize under the electron beam, x-ray lines having severe overlap or complicated background correction, matrices with severe characteristic or continuum fluorescence corrections, samples whose calculated compositions vary dramatically depending on which procedures were used to ÒcorrectÓ the data. In this tutorial, we will take an x-ray emission spectral tour of the periodic table to try to identify a number of these Òblack holesÓ and suggest ways of dealing with them without getting sucked into producing bad analysis results.

---

Other Events

---

The computer workshop and software exchange will be operating throughout the meeting. Participants can view and discuss the more than 500 megabytes of data, programs, general information and images available in the public domain software libraries. A number of Macs and PCs will be available for viewing, discussing, and copying programs. Individuals are encouraged to bring blank formatted disks with them. Live connections to the Internet will be available. Also see the ÒAdvances in Remote Microscopy, Automation and Data StorageÓ symposia.

Return to Table of Contents       Return to MSA Home Page