bluuebunny/crossref_metadata_2025 huggingface dataset:
Flies in a Box
Authors: Connelly Patricia S , Ruggiero Linda
Published: March 2018

A challenge was presented to us to find a way to support Drosophila melanogaster so that both the anterior and posterior scutellars could be easily visualized under a dissecting microscope and photographed for purpose of measurement. The resulting solution was to utilize a standard grid box with the lid removed. Several holes were filled with Gary's Magic Mountant to just above the rim of the hole. Freshly dead fruitflies were gently lifted with forceps. Then each was placed into a filled hole and both the head and abdomen were pushed into the mountant. The wings were arranged on the plastic on either side of the hole as seen in the micrographs.

The best results were obtained if the body of the fly was evenly covered with Gary's Magic Mountant and if the photography was accomplished within a few hours of the death of the fly.
Electron Tomography
Authors: Carmichael Stephen W
Published: March 2018

The transmission electron microscope (TEM) was invented in the 1930's, and developments in specimen preparation in the 1950's led to its widespread use as a tool to study structure in biologic systems. Similar in principle to the light microscope, but utilizing a much shorter wavelength for better resolution, the TEM has the image-forming beam pass through the specimen. This results in a two-dimensional image which can be difficult to interpret because features from different depths of the three dimensional specimen are superimposed. Traditionally this was dealt with by cutting sections of plastic-embedded specimens so thin (in the 40 to SO nanometer range) that they effectively had only two dimensions. To allow biologists to examine structures in three dimensions, serial sections are stacked and structures reconstructed. Even though computers have made reconstruction easier, the reality is that resolution in the depth dimension is limited by the section thickness. The technique of electron tomography is emerging as a way to overcome this limitation.
A 90-Degree-Tilt Rotary Adapter for SEM
Authors: Ehrman James M , Kaczmarska Irena
Published: March 2018

Many SEM stages prevent effective examination of specimens at extremely high tilt angles. Stage tilt may not be allowed at or near 90 degrees, and the design of the stage may cause the loss of X or Y stage motion at high tilts. We designed an adapter for our microscope that solves both problems by shifting the normal stage rotation motion 90 degrees (Figure 1). Specimen stubs are mounted horizontally in the adapter, and all components of the holder except the base plate are tethered to a stationary portion of the stage. Operation of the stage rotation control then rotates the stub around its horizontal axis (similar to a rotisserie). Specimens can be rotated through 360 degrees along this axis, with a full range of X and Y stage movement. A limited amount of stage tilt is also possible, allowing precise positioning of the specimen.
Measuring Conductivity With Scanning Probe Microscopes
Authors: Kalinin Sergei
Published: March 2018

There are two kinds of conductivity measurements possible with scanning probe microscopy (SPM). In the first case, the specific resistance of material directly below the tip is probed. In the second case, SPM probes local potential induced by the lateral current applied through macroscopic contacts, thus providing the information on the mesoscopic transport properties of the sample.

The first set of techniques is invariably based on measuring tip-surface current in contact or intermittent tapping mode. If the tip-surface contact resistance is small (good contact), the current will be limited by the spreading resistance of the sample from which specific resistance can be calculated, assuming that the contact area is known.
Adobe Photoshop® 6.0 Distilled: Preparation of Micrographs for Publication
Authors: Carvalho Tina Weatherby
Published: March 2018

A picture is said to be worth a thousand words; in the different fields of microscopy pictures are often our data as well. We interpret, analyze, and share images with our colleagues, and so image preparation, enhancement and presentation are crucial for this process. As image acquisition in microscopy moves away from capture on photographic film in favor of digital imaging methods, digital manipulation of visual data for presentation requires learning to use computer software tools. Adobe Photoshop, currently the standard in the community of both artists and scientists, is a powerful program, but it is NOT specifically designed for scientific data, and so contains dozens of features and tools that may and/or must be avoided in the preparation of micrographs for scientific publication. The learning curve for this type of software can be steep, but the steps outlined below may help to get you started.
The Emergence of Aberration Correctors for Electron Lenses
Authors: Silcox John
Published: March 2018

In 1936, Otto Scherzer published his famous theoretical paper on the correction of aberrations in round magnetic electron lenses. For fundamental reasons, the aberration coefficients are positive and to introduce negative corrections, the electron optical elements have to produce either charges or poles on the optic axis, or contain a mirror or be a multipole system. In 1997, three papers appeared with actual demonstrations of the correction of aberrations in imaging lenses, probe forming lenses and electron mirrors. It took almost two thirds of a century for this seemingly straightforward development to occur and for the promise of wavelength limited electron imaging to emerge as a practical proposition.
All That Glitters is not Gold: Approaches to Labeling for EM
Authors: Albrecht RM , Meyer DA
Published: March 2018

A large number of natural and synthetic species ranging from virus particles to small polymer beads have been employed over trie years as labels in electron microscopic applications. Perhaps the most useful and versatile of these labels are the colloidal heavy metals. The colloidal labels can be synthesized as round regular spheres in sizes from 1 to 150 nanometers in diameter and thus can be used where molecular and sub-molecular ranges of spatial resolution are required. They are electron “dense” and good emitters of secondary and back-scattered electrons and hence are readily detectable in both scanning electron microscopic imaging systems and transmission electron imaging systems. Larger particles, 10nm and above, can be identified via their shape in force based imaging systems.
Spectral Image Analysis: Getting The most from all That Data
Authors: Kotula PG , Keenan MR , Loehman R
Published: March 2018

How do you comprehensively analyze the chemistry of a microstructure with an SEM equipped with an energy-dispersive x-ray spectrometer (EDXS)? Prior to the 1990's there would have been perhaps two distinct and commercially available solutions to this problem. Firstly, you could have collected a number of point spectra each with a large number of counts and individually analyzed each one. The positive aspect of this, in principle, is that for each point the elemental correlations are maintained (e.g., a given point contains Al and O). The potential problem is that the region of the point analysis in question is not representative of the microstructure as a whole or subtle differences between different points could be missed. Additionally, point analyses are quite subjective and prone to missing potentially important regions of the microstructure.
Optical Projection Tomography
Authors: Carmichael Stephen W , Boppart Stephen A
Published: March 2018

There are many approaches to obtaining high-resolution images and three dimensional volumetric data sets, but all have limitations. Many techniques involve reconstructing volumes of information from sections, either physical sections or optical sections. Recently, James Sharpe, Ulf Ahlgren, Paul Perry, Bill Hill, Allyson Ross, Jacob Hecksher-Sørensen, Richard Baldock, and Duncan Davidson have developed an optical technique that is analogous to computed tomography (CT). Whereas clinical CT involves an X-ray source and detector rotating around the patient, optical projection tomography (OPT) has the specimen rotating within an optical pathway.
In situ Generation of Ruthenium Tetroxide and Osmium Tetroxide for the Physical Sciences and Their Reaction Indicators
Authors: Beauregard Paul
Published: March 2018

Recently, there was a suggestion on the MSA listserver about the use of osmium tetroxide (OsO4 and how to handle it. One suggestion was that ampoules be scored, placed in a glass jar, and the ampoule smashed to release the contents. This seemed like a very unsafe way to use osmium tetroxide or ruthenium tetroxide. The purpose of this article is to suggest a way to generate smaller amounts of these compounds in a safer manner than smashing ampoules and wondering about what to do with the unused portion after staining or storing. Another purpose is to discuss a new reaction indicator for mainly osmium tetroxide. The use of a reaction specific indicator was mandatory for judging the level or degree to which staining had proceeded in thin sections for the transmission electron microscope (TEM).
Use Adobe Acrobat to Keep Original Resolutions and to Make TIFF files from any Program
Authors: Sedgewick Jerry
Published: March 2018

The use of electronic files made universally readable in Adobe Acrobat will eventually replace paper submission in nearly every avenue used by scientists, whether files go to grants agencies, to reviewers, to colleagues via e-mail, or to publishers. It's for the obvious reason of reducing paper and the costs of mailing, but also because fonts often misbehave when going across operating system platforms, and because seemingly everyone has the Acrobat Reader, A better understanding of Adobe Acrobat can go a long way toward reducing the frustration that can easily arise from using this program inappropriately and ending up with poor image resolution.
Diffracted Light Contrast: Improving the Resolution of a Basic Light Microscope by an Order of Magnitude
Authors: Barry Piekos W
Published: March 2018

The discovery that the diffracted light from a convex edge can be used to form a very high-quality, shadowcast image on any light microscope has led to a device and method, diffracted-light contrast (DLC), which will allow shadowcast imaging to be routinely performed on student/laboratory microscopes (Piekos, 1999, 2003). The surface lattice of Surirella gema was easily resolved, and micrographs comparing the subcellular details of buccal epithelial cells viewed with DLC vs. Nomarski DIC showed that, on the microscopes used, DLC was superior in both the detail it rendered and depth of field. Although the images presented revealed DLC to be an excellent technique, the full capabilities of the technique were not known at the time.
Nature's Engineering Marvels: the Structure and Chemistry of a Butterfly Wing
Authors: Smentkowski VS , Ostrowski SG , Olson EJ , Cournoyer J , Dovidenko K , Potyrailo RA
Published: March 2018

Much effort is currently being expended in nanotechnology and other fields to build biomimetic, or nature-inspired, materials. The first step in this process is often to develop a more complete understanding of the structure and chemistry of biological systems. In this article, we will compare and contrast data collected on a common biological sample, a butterfly wing, using a variety of analytical techniques. Transmission Electron Microscopy (TEM) was used in order to perform bright field imaging of the sample cross section; Light Microscopy (LM) and Scanning Electron Microscopy (SEM) were used to provide structural information of the outer wing surface at various magnifications; Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) was used in order to image the chemical composition of the outer most surface layer; and Focused Ion Beam (FIB) techniques were used to cut (micro machine) features into the wing.
Images from Minne“Snow”ta
Authors: Schenk Kurt , Hanke Larry
Published: March 2018

When the workload is light, we like to hone our skills by performing analysis on difficult samples (or at least that's the justification for this particular diversion). During the long winter of 1996-97, we took up the challenge of imaging snowflakes using our scanning electron microscope (SEM). Snow, being both nonconductive and liquid at room temperature, provides some challenges to the microscopist.

We have a JEOL 5800LV, which when operating in “Low Vacuum” mode, can image nonconductive samples without charging. This is achieved by allowing a relatively high pressure in the sample chamber. The air in the chamber ionizes in the beam and neutralizes the charge buildup on the sample.
Equipment Maintenance: Vender Service Contract vs. Independent Providers vs. Insurance Company/Self-insure Options M&M 2000 Expert's Session on Facility Management
Authors: Sherman Debby
Published: March 2018

This article is the second of a series transcribed from the discussion taped during the Facility Management session at M&M 2000. It is printed with permission of the Microscopy Society of America. Bulleted paragraphs indicate comments by individuals attending the session.
Energy-Filtered Imaging
Authors: Bentley J
Published: March 2018

Over the several years that imaging energy filters have been available commercially, numerous and wide-ranging applications have demonstrated elemental mapping with a resolution approaching 1 nm. A few reports have even shown resolutions <0.4 nm. Elemental mapping by energy-filtered transmission electron microscopy (Eftem) is clearly an attractive and powerful tool, but some aspects of the techniques can be complex, with many pitfalls awaiting the unwary. This tutorial aims to cover some practical aspects of elemental mapping by Eftem. It is based largely on the author's work at the ORNL Share User Facility, where Eftem research has been performed since 1994 with a Gatan imaging filter (GIF) interfaced to a Philips CM30T operated at 300 kV with a LaB6 cathode. Most of the applications have been to metals and ceramics, emphasizing interfacial segregation and precipitation.
The Energy Spectra of Secondary Electrons
Authors: Joy David C , Braski David
Published: March 2018

It has been estimated that more than 90% of all scanning electron microscope (SEM) images ever published have been obtained using secondary electrons (SE) which are defined as those electrons emitted with energies between 0 and 50 eV. The properties of these secondary electrons are therefore of considerable interest and importance. However, although secondary electrons have been intensively studied since their discovery by Starke in 1901, the majority of the work has been aimed at determining the SE yield coefficient and its variation with energy for elements and compounds. The energy spectrum of secondary electrons has received far less attention although it is evident that the form of the spectrum must have an effect on the image contrast observed in the SEM because SE detectors are energy selective devices. The few studies that have been made have mostly concentrated on spectra obtained from clean samples observed under ultra-high vacuum conditions.
Safe Disposal of Mercury Salts
Authors: Llewellyn Bryan D
Published: March 2018

Make sure that gloves are worn for this procedure. All containers and gloves used should be rinsed with water and the water put in the waste mercury container for next time.

All solutions containing mercury salts are collected into a jar labelled “Used Mercury Salts”. We keep this in our grossing room. The jar is actually a clear glass 3 kg sodium phosphate container.

When the jar is about half full, to each 900 mL (estimate, don't measure) add 40 grams of sodium carbonate to raise the pH to 8.0 or higher and mix well.

Leave it for a while, then filter the solution and collect the precipitate into a plastic jar for disposal. Put the filter paper in the jar as well. Seal the jar very well. We coat the lid with several layers of paraffin wax until it is about a quarter inch thick.
Probing Ribosomal RNA By Electron Spectroscopic Imaging and Three-Dimensional Reconstruction
Authors: Beniac Daniel R , Czarnota Gregory J , Rutherford Brenda L , Ottensmeyer F Peter , Harauz George
Published: March 2018

The ribosome is the protein synthetic machinery in the cell. Knowledge of the structures of ribosomal RNA (rRNA) macromolecules in situ is essential to understanding their roles in ribosome mediated protein synthesis. We are using a microanalytical technique that identifies and maps elements directly, electron spectroscopic imaging, to determine the rRNA phosphorus distributions within Escherichia coli ribosomal subunits, and to combine the two-dimensional maps into a three-dimensional elemental distribution by iterative quaternion-assisted angular reconstitution of ribosomal particles at random orientations.
Backside Etching of GaAs Devices
Authors: Mittereder Jeffrey A
Published: March 2018

The following is a technique for analyzing the area underneath a GaAs integrated circuit or discrete device which may aid in failure analysis. This procedure has been used in the past by the microelectronics community, and it is reviewed here for GaAs monolithic microwave integrated circuits (MMICs) and discrete devices. Because it is a destructive method, we use it in our lab after all other testing is completed. The substrate thickness of the GaAs is ∼4 mils (25 μm).
Rotary Pump Dual Filters
Authors: Basquall Ed
Published: March 2018

Rotary vacuum pumps are used in virtually every research lab, especially those engaged in vacuum science such as electron microscopy and mass spectrometry. In the majority of these situations the exhaust can and should be vented to the outside. Unfortunately, many labs lack this capability. Oil mist vapors emitted from pumps under a load can be quite annoying and may be a potential health hazard. Pumps located in small confined spaces such as microscope rooms, darkrooms, etc. are particularly a problem. Often the manufacturer supplied filters are either inadequate or poorly maintained.
So Why is the Chemical Symbol for Tungsten "W"?
Authors: Darus Mark
Published: March 2018

The tungsten mineral wolframite was known in the tin mines of the Saxony-Bohemia region long before the element itself was discovered. The origin of the word is assumed to be derived from the German words "wolf, meaning beast of prey, and "rham", meaning froth. "It eats up tin as a wolf eats up sheep". The writers of the period before 1781 had vague ideas as to the composition of the mineral that they had named. Tin miners called the mineral "mock-lead", an ore containing iron, arsenic, tin and a nonmetallic earth, or glassy earth containing iron and tin.
Tips On Finding A Good Etchant For Metals
Authors: Kestel Bernard
Published: March 2018

Start with a handbook of chemistry and physics, In the tables of physical constants will be listed the metals solubilities in various acids. Pick an appropriate acid, and as a first try use 10% acid in methanol (a good electrical conductor). Ethanol is less conductive and more viscous than methanol. Always check chemical safety before starting. Never mix nitric acid with ethanol, for example; it explodes above a 5% concentration. Chill the solvent to at least 0° C before adding acid.
Rare Earth - Fe2 Thin Films Study With Strata™
Authors: Claude J M , Thiot J F , Oderno V , Dufour C
Published: March 2018

The Rare-Earth Laves phases RE-Fe2 (RE represent the Rare-Earth) show large magnetostrictive properties, especially at room temperature. These materials are well characterized when in bulk form, but they have rarely been studied as thin films and one can expect some important effects due to epitaxial growth.

A few single crystal layers of RE-Fe2 have been studied (YFe2, TbFe2, DyFe2, ErFe2: and Dy0.7Tb0.3Fe2 known as Terfenol-D). The thickness of these different layers are between 5 and 20 nm and with [110] as a growth direction have been epitaxied. They have been deposited with a Molecular Beam Epitaxy (MBE) in an ultra high vacuum chamber. A [1120] sapphire substrate is recovered by a [110] niobium buffer. The RE and the iron are then co-deposited on the substrate which is maintained at 500°C. Lastly, an Yttrium layer is deposited on the Rare Earth material at a temperature close to ambient.
TEM Sample Preparation for the Semiconductor Industry — Part 3
Authors: Walker John F
Published: March 2018

Part 1 of this series described how focused ion beam (FIB) microsurgery is used to successfully cross-section and prepare materialspecific samples for SEM and TEM analysis. In Part 2, we detailed how FIB is also the tool of choice to prepare site-specific samples, particularly for transmission electron microscopy (TEM) analysis. In this final article of this series, we describe actual sample preparation, cutting a selected area la size and mounting it on a grid for FIB preparation. Focused ion beams are very useful in preparing TEM specimens that have unique characteristics. In particular, the ability of such systems to image submicron features within a structure has allowed accurate identification of the precise place to make a membrane.
Contemporary Problems in Science Jobs (Second Edition) Part 2: What Good CVs Look Like! (The Science Career Path Reality)
Authors: Sowers Arthur E
Published: March 2018

My 9 years in industry, 5 years in academia, and 4 years as a postdoc tell me this about getting a regular (tenure-track) faculty appointment:

On a very simple level, one who wishes to be in lofty pursuits (an academic position at a research institution, where the goals are noble and the intellectual rewards are pure and at least some people respect you) would follow this conventional-wisdom paradigm:

First get a Ph.D (or MD/Ph.D), next get a postdoc, and then get an assistant “prof.” position.
Tricks of the Trade: Particle Mounting Methods
Authors: McCrone Walter C
Published: March 2018

Those of us who have particle identification problems sometimes have very small samples, say, only a few nanograms - even less sometimes. We also like to make up permanent Aroclor 5442 preparations of these tiny samples for safe keeping and future reference. If we mount such small samples in a normal drop of Aroclor filling an 18 mm diameter coverslip, we may spend a few frustrating minutes looking for the sample in a few acres of Aroclor. My solution is to use a very tiny Arocior droplet under a small coverslip. Ten millimeter or smaller round coverslips are available from Erie Scientific in Portsmouth, New Hampshire.
Resolution, Flexibility, and Quality offered by Dual Robinson Backscattered Electron Detectors
Authors: Cecere Paula A
Published: March 2018

Over the years, efficiency of backscattered electron detectors has improved. Robinson has developed a unique system whereby two BSE detectors are used, offering an array of benefits to the SEM operator. The system consists of two detectors with scintillators of dedicated geometrical shape, providing a collection area greater than 2000 mm2. They are situated against the axis of the electron beam, with the right and left signals combining to form the overall image signal - one that is 1.5 times greater than that of a single detector. The omnidirectional image illumination, similar to that attained thorough a traditional SE detector, prevents shadowing due to the 180° collection angle.
The Difference Between Calibration and Image Linearity
Authors: Hansen Douglas
Published: March 2018

In my last article, I discussed the need for scheduled system checks on scanning electron microscopes. The article used an experience at a local SEM laboratory to point out the importance of monitoring your instrument by performing simple but regular system performance evaluations.

In this article I will discuss some principles behind the performance of imaging systems such as scanning electron and scanning probe microscopes. We will talk about the concepts of image linearity and dimensional calibration.
Using Antibodies to Make Images
Authors: Carmichael Stephen W
Published: March 2018

The atomic force microscope (AFM), the workhorse of scanning probe microscopes, has become even more versatile. Anneliese Raab, Wenhai Han, Dirk Badt, Sandra Smith-Gill, Stuart Lindsay, Hansgeorg Schindler, and Peter Hinterdorfer have demonstrated that the AFM, in the dynamic force mode, can use antibodies as a probe. Dynamic force microscopy uses a magnetized tip that is oscillated in an alternating magnetic field as the tip scans the surface. This provides a very gentile interaction that can be recorded as a high resolution topographic image. Raab et al., showed that more information can be obtained from the specimen.
Cryoprotectant Tissue Storage Solutions: Stability at Lower Temperatures, Longer Storage Times, More Versatile Usage
Authors: Simmons Donna M
Published: March 2018

Infusion with buffer/sucrose solutions (up to 30% sucrose) has long been used to ‘cryoprotect’ tissue in an attempt to prevent ice crystal artifact in frozen sections. This is helpful for example in sectioning large, fixed tissue blocks that must be frozen relatively slowly in dry ice to allow sectioning on a sliding microtome. In 1977, De Olmos added ethylene glycol to the mixture (30 g cane sugar/50 ml 0.1 M PO4 buffer at pH 7.2 in 20 ml ethylene glycoi) for -10°C storage of free floating sections from lightly fixed primate brain. Jones and Kane in 78 used this solution for storage of sections at -20°C (standard household freezer temperature) for up to one month before horseradish peroxidase histochemical reaction, in their methods, they cautioned that "sucrose attracts insects" (ants, personal communication). We and others have found the above cryoprotectant solution generally useful for storage of free floating sections from fixed brain. We observed that adjacent sections stored at 4°C in buffer for 2 weeks (common practice for Nissl stained sections) lost their reactivity to antibody labelling.
Don't Store Osmium Tetroxide in Plastic Containers
Authors: Jeffree Chris
Published: March 2018

It is not safeto store osmium in ordinary laboratory plastic containers. Osmium penetrates polyolefin plastics (polyethylene, polypropylene) to some depth, and reacts with them, so containers made from these plastics or of polystyrene or polycarbonate with polyolefin closures are not recommended.

Osmium is usually supplied with some protective packaging and, should further security be desired, I would consider placing the glass ampoules inside polyethylene or polypropylene tubes. This would allow considerable shock protection and, if the ampoule did break, the outer container would protect against leakage for the short time required to get it to a fume cupboard. The same principle can be applied to osmium solutions prepared in glass bottles: enclosure in an outer polyethylene bottle will give shock protection and temporary containment. Also, its blackening indicates how much leakage has occurred from the supposedly closed glass container.

In this regard, we have a rule that osmium solutions are never stored in the laboratory refrigerator.
Directing Traffic in Lymph Nodes
Authors: Carmichael Stephen W , Remstein Ellen D
Published: March 2018

How do the right cells get to the right place in lymph nodes? It is known that lymphocytes known as B cells (that originate in the bone marrow) migrate to follicles within the nodes, whereas T cells (that originate in the bone marrow and migrate to the thymus gland) reside in an adjacent region known as the paracortex. By combining confocal, electron, and intravital microscopy, Marc Bajénoff, Jackson Egen, Lily Koo, Jean Pierre Laugier, Frédéric Brau, Nicolas Glaichenhaus, and Ronald Germain have demonstrated a role for the stroma of the node in directing these cells to the appropriate location. The stromal cells that are critical in the B cell follicles are follicular dendritic cells (FDCs) and in the paracortex it's the fibroblastic reticular cells (FRCs).
Multi-Length Scale Characterization of the Gibeon Meteorite using Electron Backscatter Diffraction
Authors: Nowell Matthew M , Carpenter John O
Published: March 2018

The Gibeon meteorite is a differentiated iron meteorite that fell in Nambia, Africa in prehistoric times, with fragments spread over an area 70 miles wide and 230 miles long. The Gibeon fall was initially discovered in 1836, and hundreds of thousands of kilograms of fragments have been recovered. These fragments represent the iron core of a meteorite that cooled and crystallized over thousands of years (Norton 2002).

The microstructure of the Gibeon meteorite, which is primarily an iron-nickel alloy, consists of two phases: kamacite, a body-centered cubic material and taenite, a face-centered cubic material that metallurgists would refer to as ferrite and austenite respectively. This material initially crystallizes as taenite, and as the temperature decreases, transforms into kamacite. This meteorite is classified as a Fine Octahedrite (Of) with an average Nickel content of approximately 7.9%
Applications of Focused Ion Beam (FIB) on Yeast Cell & SARS Virus
Authors: Hing H L , Burkhardt C , Gnauck P , Sally S , Gelderbloms H , Muranaka Y , Kaswandi MA , Azizl AHA , Sahalan AZ
Published: March 2018

The focused ion beam (FIB) is a relatively novel technique to biomedical electron microscopy as it open up new means for the observations and examinations of a wide range of biomedical and biological materials. The focused ion beam, or FIB tool has been utilized mainly in the fields of material sciences and industry. The (FIB) uses high-energy gallium ions to precisely and accurately section or mill samples. Lately FIB method have been used to prepare biological samples such as yeast cells and virus particles. Yeast cells Schwanniomyces occidentalis S. occidentalis were prepared by vacuum sucking them into cellulose tubing, plunge freezing them in liquid nitrogen, followed by chemical fixation in glutaraldehye and postfixed with osmium tetroxide, dehydrated in a series of ascending alcohol concentration up to absolute alcohol, then freeze dried overnight. In the case of SARS virus, the tissue culture containing virus particles was chemically fixed with glutaraldehyde, dehydrated in ascending order of alcohol concentrations and then freeze dried.
Advanced Metallographic Techniques Applied to Diesel Particulate Filters
Authors: Saenz Natalio , Dillon Heather , Carlson Shelley , Maupin Gary
Published: March 2018

Diesel Particulate Filters (DPFs) are designed to capture exhaust particulates from engines. The filter material collects the particulates deep in the substrate (deep-bed filtration) before transitioning to other filtration methods on the surface. The deep-bed filtration has been characterized by modeling studies but little experimental information about the particulate, or soot, penetration in the filter material is available. Traditional evaluation methods do not provide sufficient contrast between the soot and mounting resins.

Due to the difficulty of locating carbon soot in the pores in these filters, ultra-thin section techniques (under 10-micron-thick sections) were used for the characterization of these samples. Under transmitted light, the carbon soot is black because it blocks the light, and the carbon in the resin material is relatively clear.
Platform Wars: Macintosh-Based Digitization Systems
Authors: Krivanek O L , Hunt J A
Published: March 2018

Improvements over the past few years in essentially all modern operating systems coupled with the blurring of the boundaries between mainframes, workstations, and personal computers make the choice of platform often one of personal preference other than of necessity. A decade ago there were very distinct differences between the features offered by IBM PC and clones, the Apple Macintosh, and UNIX workstations. These differences included price, processing performance, OS features, look and feel, graphical capabilities, memory and disk limitations, networking capabilities, ease of- use, system stability, development tools, etc. Since then many of these distinguishing differences have evaporated making platform selection a more subtle issue, but also much less important. However, there are still a great many users thai tend to make such decisions based on their “religious” preference of platform rather than based on objective information.
Three Dimensional Deconvolution Of Microscope Data
Authors: Richardson Michael
Published: March 2018

Advances in computer processing power have enabled new threedimensional image enhancement and visualization techniques. Data storage capacities of a gigabyte or more are affordable and commonplace. The Power Macintosh computers are RISC based processors which perform graphical and computational tasks many times faster than the older 68000 based systems. These new systems are ideal platforms for threedimensional deconvolution of microscope data sets.
SEM-Fix
Authors: Mott Rick
Published: March 2018

The most unusual use I've seen for an SEM was as a special-effects generator for the fifth Star Trek movie, “The Final Frontier”, William Shatner directed the film as well as starring in it. He chose Bran Ferren of Associates and Ferren, now part of Disney Imagineering, to do the special effects. Ferren had the idea of using SEM imagery for the “eerie planet in the center of the galaxy”, because the large in-focus depth of field gave an unearthly feel to the scene. Shatner was fascinated by the technology and the resulting images.

When you hear that a film cost $50 million to make, here's how it happens. They bought a Zeiss 960 SEM and a PGT IMIX system just for that one sequence in the movie! A mainstay of movie effects is model animation, in which miniatures are dragged along suspended wires while one or more cameras (mounted on articulated robotic booms) also move to produce She complex and realistic action you see on the screen.
Computer-Controlled Polishing System For Preparing Multiple Pre-FIB TEM Specimens
Authors: MacMahon D J , Raz-Moyal E
Published: March 2018

Semiconductor manufacturers are increasingly turning to Transmission Electron Microscopes (TEMs) to monitor product yield and process control, analyze defects, and investigate interface layer morphology. To prepare TEM specimens, Focused Ion Beam (FIB) technology is an invaluable tool, yielding a standard milled TEM lamella approximately 15 μm wide, 5 μm deep and ~100 nm thick. Several techniques have been developed to extract these tiny objects from a large wafer and view it in the TEM. These techniques, including ex-situ lift-out, H-bar, and in-situ lift-out, have different advantages and disadvantages, but all require painstaking preparation of one specimen at a time.
Tissue Printing for Scanning Electron Microscopy and Microanalysis
Authors: Reine Barbara A
Published: March 2018

The study of plant morphology and plant cells in the scanning electron microscope is often compromised by the limitations of specimen preparation techniques. Air drying usually results in unacceptable shrinkage and distortion of the normal surface morphology of plant cells. Chemical fixation followed by critical point drying or chemical drying using fluorocarbon compounds improves morphological results but still imparts artifacts, adds chemical constituents to the specimen, and requires the use of toxic chemicals, a hood, and much time.

One technique that eliminates many of these disadvantages and is even suitable for specimen preparation in the field is tissue printing. For easy, quick recording of stem anatomy and collection of cell exudates for subsequent analysis, its “elegant simlicity” is compelling. Historically, the application of tissue printing has been in connection with optical microscopy. However, this technique works very well for SEM and associated elemental characterization of residues by x-ray microanalysis. The tissue print technique applied to SEM is much the same as for optical microscopy.
Are Microscopes Too Sophisticated?
Authors: Goodhew Peter
Published: March 2018

I bought my last useful pocket calculator in 1975 and I still use it regularly. Every time I pick it up I know how to use it, since all the functions I need are printed on its buttons, and I expect to be using it when I retire, if I can still get the batteries. My son bought a “more sophisticated” calculator for his A-levels in 1988 and I inherited it shortly thereafter, it lies in my desk drawer but I cannot use it because it offers so much more than I need and there is too much printed on and around each button. I would need to read the manual every time I wanted to use it. On the desktop close by sits my telephone: It has 46 buttons and a 17-page manual and offers an enticing array of facilities. Unfortunately I only need each of these “facilities” about once a month and have never been able to memorize the necessary procedures. As a result all I can do is answer it when it rings and dial out.
What Is It You Want From Us?
Authors: Soeldner Al
Published: March 2018

I manage a university service electron microscope facility which provides transmission, scanning transmission, and scanning electron microscopy, each with X-ray energy spectrometry, as well as feature analysis, specimen preparation, and training services. Clients of the facility do basic and applied research in:

human, animal, and plant health, pharmacy, and bioengineering; air, water, and soil ecology, pollution, and resource development and conservation; forest pathology, productivity, and development and performance of wood products; foods and nutrition: engineering, advanced metallic, ceramic, glass, and polymeric materials development, failure analysis, and tribology: botany, entomology, microbiology, zoology, chemistry, geology, and physics.
Scanned Probe Microscopy in Biology
Authors: Fisher Knute A
Published: March 2018

Numerous scanned probe microscopes (SPM) have been developed over the past decade. Most are based on the precise positioning of sample and probe using piezoelectric transducers, and some have the capability of imaging flat surfaces with atomic resolution. The first atomic resolution SPM applied to biological samples was the scanning tunneling microscope (STM). The atomic force microscope (AFM) was subsequently developed and over the past few years has become the instrument of choice for biological applications.
The NSOM Technique And It's Significance
Authors: Aden Gary
Published: March 2018

Prior to Near-Field Scanning Optical Microscopy (NSOM) there were two major light microscopy techniques; optical and confocal.

In an optical microscope a sample is illuminated with a flood of light. The lighted area is then imaged and magnified by collecting the light that is either reflected from or transmitted through the sample by a series of glass lenses. A color magnified image of the sample may be seen directly or displayed on a TV screen. Even if the lenses could be made perfectly, the resolution and magnification of an optical microscope are limited by diffraction effects to approximately one half of the wavelength of the light that is used. Optical microscopes are used routinely to image the general shape of samples as small as human chromosomes or compact disk bits.
Preparation of 2″ X 2″ Projection Slides From EM And Other Negatives
Authors: Christensen A Kent
Published: March 2018

In the early days of biological electron microscopy (the 1950s and 1960s), projection slides of electron micrographs for talks or teaching were generally prepared as 3-1/2″ X 4″ lantern slides, which were shown using large lantern-slide projectors. It was felt by professional electron microscopists that the detail, tones, and general image quality of electron micrographs could be adequately portrayed only in this larger format.

However the large lantern slides were very cumbersome, and most professionals began switching to 2″ X 2″ slides in the early 1970s. Some of us during that period put in a great deal of time trying to work out a procedure for printing EM negatives directly on 2″ X 2″ glass Kodak Projector Slide Plates, following the general approach by which we had previously made the 3-1/4″ X 4″ lantern slides.
Modern Microscopy - On the Light Side! Microanalysis Surprises
Authors: Niemeyer Wayne D
Published: March 2018

How many of the analytical chemists reading this will identify with the following scenario? A customer gives you a sample with a contaminant and asks you to identify the material. Your customer provides a very logical dissertation on what the material is likely to be. With that bias firmly entrenched in your mind, you proceed with the analysis, fully expecting to find what your customer said you should. However, during the course of your analysis, you discover that the contaminant is something completely different than expected. Now you are presented with the dilemma of facing that customer to explain the “unexpected” result. You are immediately put on the defensive by being accused of not having properly calibrated instruments or you have obviously contaminated the sample with something else during sample preparation, etc. These situations occur in laboratories all over the world.
More than One Ever Wanted To Know About X-Ray Detectors Part 3: Who Put Promethium in My Soup?
Authors: Lund Mark W
Published: March 2018

The combination of electron microscope and x-ray spectrometer is a very powerful tool. Not only can one see a sample in great detail, but one can determine, and even map, the chemical elements, in Part 1, I discussed some of the basics of energy dispersive x-ray spectroscopy (EDS, EDX). In Part 2,1 went into detail about the construction of the detector, and discussed counting statistics. In this installment I will discuss the interaction between the x-ray and the detecting crystal, things that can go wrong in the process, and the phenomena which can make false peaks in a spectrum.
Orientated Imaging Microscopy
Authors: Field David P
Published: March 2018

With the complexity of polycrystalline materials, a number of techniques have evolved to assist in the resolution of the crystallography of these materials. Conventional methods provide partial information regarding grain size, and can produce estimated orientation distributions. However, these techniques have not been able to provide the spatial placement of lattice orientations, which is necessary for a complete picture of the microstructure of a materials sample. Furthermore, many materials characteristics, such as fracture and corrosion, are determined by site-specific, rather than average, crystal lographic features.
The Making of LaB6 Crystals
Authors: Heer Damon L
Published: March 2018

The following image is of a LaB6 crystal formation created at the FEI Company, Hillsboro, Oregon. The photograph was taken through a Bausch & Lomb Stereo Zoom 4 at 30X with a Polaroid MicraCam.

The single crystal LaB6 and CeB6 is grown and fabricated at FEI using a well-defined process known as "Inert Gas Arc Float Zone Refining." This process takes place in an inert gas atmosphere and utilizes an electrical arc to melt the hot, pressed powder sample of LaB6 or CeB6. This not only allows the growth of the crystal, but also hefps to purify the material. Through research and 20 years of experience in the growth of rare-earth boride single crystals, FEI can carefully control the material composition (e.g. stoichiometry of B/La) tor the highest possible ratio of electron emission to evaporation rate.
X-ray Image Compression: 16 Bit Counts Into 8 Bit Space
Authors: Engle PD , Herrington CR , Geller JD
Published: March 2018

One way to improve upon the detection limits for digital images involves increasing the number of counts per pixel. Eight bits, or 1 byte (256 counts), per pixel is most commonly used for monochrome optical, electron and x-ray imaging. This number is well matched to the human eye which can discern approximately 128 gray values, while photographic and some laser printer outputs have the capability of displaying nearly 256 gray values. When the counts exceed 8 bits/pixel the recorded image file size will likely double to 16 bits/pixel. With the better imaging detection limits we are faced with the technical problem of how to view more than 256 gray levels.
Zepto and Yocto: The Missing Marx Brothers
Authors: Levy Gabor B
Published: March 2018

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.
3D Microscopy: Confocal, Deconvolution or Both?
Authors: Pawley JB , Czymmek K
Published: March 2018

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.
The Unusual Degradation of Recordable Compact Discs
Authors: Martin James
Published: March 2018

The recordable compact disc (CDR) is a popular and inexpensive medium for storing and disseminating digital information, such as micrographs and scanned images. This technical note describes unusual degradation that rendered a group of discs unreadable. The discs were purchased as a set. Each disc was packaged in a jewel box and wrapped in clear plastic. Several of the discs were used within weeks of purchase to store data, which included digital micrographs.
3-D Reconstruction of Thick IVEM Samples Using Tuned Aperture Computed Tomography® (TACT®)
Authors: Jerome W Gray , Grant Ken , Yancey Patricia G , Gailany A M Al , Betterman Wolfram , Webber Richard L
Published: March 2018

Most objects in our world are 3-dimensionai (3-D), and this is certainly true of cellular ultrastructure. The challenge in microscopy has always been how to analyze this 3-D information. Traditional thin-section microscopy has a minimal ability to view 3-D structure, because it is limited to viewing thin, almost twodimensional (2-D) planes taken from the specimen. The development of high and intermediate voltage electron microscopes (HVEM and IVEM) provides the ability to investigate the ultrastructure of thick biological samples—allowing a unique view of the 3-D interrelationships of cells and organelles.