bluuebunny/crossref_metadata_2025_split huggingface dataset:
Imaging with Photoelectrons
Authors: Carmichael Stephen W 
Published: March 2018

Abstract
Most of us have used fluorescence microscopy and are all too familiar with the advantages and disadvantages of this tool: easy identification of one or more labels that fluoresce at different wavelengths (color) against the relatively dark background of the biologic substrate, but we can't always get the spatial resolution that is needed to answer our questions. Electron microscopy, both transmission and scanning modes, offer much better spatial resolution, but present problems in localizing a label, particularly on the surface of a cell. Wouldn't it be great if an imaging technique were available that gave us the possibility of localizing one or more labels on the surface of a cell with resolution approaching electron microscopy. Karen Hedberg, Bruce Birrel, Douglas Habliston, and Hayes Griffith at the University of Oregon describe photoelectron imaging as the electron optical analogue of fluorescence microscopy, offering some of the advantages of both methods.
Beam Skirt Effects When Doing EDS In An Low-Vacuum SEM
Authors: Blide-Soerensen JB 
Published: March 2018

Abstract
Approximately 75 % of the primary electrons will be scattered when you use a working distance of 12 mm and a pressure of 3.5 torr, and a significant fraction of these scattered electrons will hit the sample farther away from the beam target than 50 pm. (The scattered intensity is approximately given by Is/ lo = 1 – exp(-ρσL/kT) where p is the pressure, σ the total scattering cross section for electron scattering on the gas used, L the distance between the last pressure limiting aperture and the sample, k the Boltzmann constant and T the absolute temperature).
The Effect of Gas Type on Beam Scatter
Authors: Chernoff Don 
Published: March 2018

Abstract
Last month I addressed the phenomena of beam scatter in the environmental and low vacuum SEM. In that article I covered how beam scatter is affected by chamber pressure, working distance, and accelerating voltage. To briefly summarize, beam scatter becomes worse at higher chamber pressure, longer working distance, and lower accelerating voltages. As the beam scatters, electrons strike the sample some distance away from the primary beam and as a result, generate X-rays from unwanted areas of the sample. It is advantageous for the analyst to keep beam scatter to a minimum to reduce the generation of these X-ray signals. Under conditions of high chamber pressure, long working distance, and low accelerating voltage, it is possible for electrons from the beam to strike the sample on the order of a millimeter or more from the primary beam.
Limits of SEM Resolution
Authors: Joy David C 
Published: March 2018

Abstract
Over the past decade the achievable resolution of the scanning electron microscope (SEM) in secondary electron (SE) imaging mode has improved by about one order of magnitude. In fact, instruments capable of demonstrating a resolution of one nanometer and exhibiting a probe size of less than 0.6 nm are not available. Continued improvements in electronoptics, electron sources, and in electronic and mechanical stability promise even smaller probe sizes that still contain adequate current for imaging, it is therefore relevant to consider what resolution might ultimately be achievable with an SEM in SE mode.
Home Made Silicone Rubber Embedding Molds
Authors: Muss Wolfgang 
Published: March 2018

Abstract
Silicone rubber embedding molds may be inexpensive In North America, but are not necessarily so elsewhere in the world. Further, commercial molds are available only in standard sizes and only with standard sizes and shapes of cavities for specimen embedding, If, however, one needs to embed specimens of n on standard size or shape, wants more embedding cavities per mold than usually available, or is working where commercial molds are expensive or not easily available, then all is not lost, Embedding molds for specimen blocks can easily be made in the lab from silicone rubber. Further, making embedding blocks allows the use of different silicone rubbers which would be of value with unusual embedding resins, or when embedding must be done in unusual environments (such as extreme cold or heat).
Scanning Electron Microscope EDucatorS
Authors: Williams Joseph P 
Published: March 2018

Abstract
Can you imagine the motivational value of a young adult being exposed to images of common day objects that they have an interest in, magnified ten, one hundred, or one thousand times? Then imagine the student learning the theory and operation of a scanning electron microscope. Finally, imagine walking into a laboratory to see these same students operating an SEM and taking their own micrographs.
For the past three years I have had the pleasure of teaching the laboratory portion of the SEMEDS program. The program's goal is not just to motivate high school students in science, but to expose them to the wonders of microscopy and how it affects their everyday life.
The program currently has three phases. During phase one, teachers from local high schools are contracted about the program. The teachers volunteer at the beginning of the school year then become students themselves during a four hour class.
Low Pressure Nitrogen Purge Stops Oil Contamination
Authors: Vane Ronald A 
Published: March 2018

Abstract
Oil contamination in SEMs is a common problem. It manifests itself as dark spots and carton buildup in low KV scans and oil condensation on EDX detector windows. While one of the most common sources of this contamination is oil backstreamed from the roughing pump, other sources include pump oils, lubricants, seals, fingerprints, and the samples themselves. Depending upon severity, this effect ranges from a minor irritation to a very major problem.
Historical solutions to this problem have included turbomolecular pumps (TMP), cryopumps, drag pumps, traps, better pump oils, cooler running roughing pumps, double diffusion pumps and fractionating diffusion pumps. Many of these solutions have proved to be costly, require much maintenance and/or have not been very effective.
High Pressure Freezing; Benefits and Limitations
Authors: Wise Robert R 
Published: March 2018

Abstract
Rapid freezing of biological samples for subsequent processing and examination in the TEM has been around since the 1960's. Freezing in general, is advantageous because it can provide an instantaneous cessation of all biological activity and hall ultrastructural rearrangement The freezing ‘fixes” biological structures in water ice until such time that the ice can be substituted for a chemical fixative. Freezing is typically conducted at liquid nitrogen temperatures (-196°C), and freeze substitution (FS) is then carried out over days to weeks on dry ice (-80°C) (Severs el. al., 1995).
A Stable, Adjustable Voltage Source to Replace Mercury Batteries in EMs and Other Instruments
Authors: (Woody) White N W 
Published: March 2018

Abstract
From time to time, a stable but adjustable voltage source can be quite handy. This article was prompted by a request for a replacement for mercury battery collage references which are not only difficult to find, but are rot environmentally friendly. Another application could be powering a 3 to 9 volt disk-man (or whatever) from a nominal 12 volt source such as an automobile. In fact, the circuit can be set to supply any collage From 3 to 38 volts.
Measuring, Stopping and Preventing Vibration in Microscopes and Other Laboratory Equipment
Authors: Leidich Richard , Listner Gregory 
Published: March 2018

Abstract
Vibration in microscopes may seem a bit baffling, but we have found that solutions to vibration problems are usually quite simple. Vibration is the result of an object being moved until it collides with another object and bounces back. Yes, it can be as simple as shaking, but the normal definition involves collisions. Some source must continuously supply energy to the moving part(s). As long as energy is supplied to the moving part(s) and the part(s) collide, bouncing can occur at a constant frequency. If the parts can be moved so they do not collide or if the energy can be absorbed, the frequency of the bouncing can be changed or stopped.
Pioloform F Instead of Formvar as a Support Film for TEM
Authors: Madden Victoria J 
Published: March 2018

Abstract
Pioloform F (Wacker Chemie Co., Munich, Germany) is an excellent plastic for use as a support film for electron microscopy. The advantages of Pioloform F are high mechanical and thermal stability, and low material bulk (Stockem, 1970). Because of these properties, thinner films than Formvar or collodion may be used and remain stable under the electron beam without subsequent stabilization by carton coating. Thin support films of gray interference color are prepared by dissolving 0.5 grams of Pioloform F powder in 100 milliliters of anhydrous chloroform (Stockem, 1970), using the dip method described by Reimer (1967).
How Good is Your Glut?
Authors: Compton Bob 
Published: March 2018

Abstract
Gluteraldehyde (GA) has proven to be an extraordinarily versatile product. Its many uses range from softening leather and paper to disinfecting and sterilizing hospital instruments. It is used, of course, as a fixative in preparing biological samples for microscopic investigations that most readers of this publication will be familiar with. Even though quality questions relating to GA have been well researched and documented, there is still enough disagreement between industry experts to stimulate an enthusiastic discussion on microscopic list servers.
He who borrows lenses borrows trouble
Authors: Newberry Sterling 
Published: March 2018

Abstract
This adage for my students was obviously inspired by "He who steals my purse steals trash" but the lens borrower may be in for more serious trouble than the purse snatcher. This comes about because the eyepiece fit and the objective threads are standardized to a couple of standards so that the mechanical interchange of components between different optical microscopes is easily accomplished, while the incompatibility of the optical components is not usually apparent. This incompatibility can range from easily recognized blurring of the image to only slight loss of resolution which leads to inferior work or much wasted time before the problem is recognized.
Microscopy In Forensic Science
Authors: Houck Max M 
Published: March 2018

Abstract
This article is the first in a series relating to the application of microscopy to forensic science. As such, the article is intended to be purely introductory in nature. Future articles will be specific both as to the forensic challenge and the solution as allowed by the creative application of microscopy.
Microscopy has played an integral part in forensic science since the early part of this century. In 1928, E. Locard established the practical and theoretical underpinnings of the microscopic examination of trace amounts of evidence. The “exchange principle of evidence” was so developed:
Whenever two objects come into contact there is always a transfer of material. The methods of detection may not be sensitive enough to demonstrate this or the decay rate may be so rapid that all evidence of transfer has vanished after a given time. Nonetheless, the transfer has taken place.
Evolution and Revolution in Microscopy - I
Authors: Revel Jean-Paul 
Published: March 2018

Abstract
Disney, Hill and Baker in their 1928 booh on the Origin and Development of the Microscope, quote the 1829 article on Optics of the London Encyclopedia as saying; “Microscopes, though but toys compared with telescopes, nevertheless deserve to be rendered as perfect as possible; for they yield not to them in the quantity and variety of rational amusement which they are capable of introducing to us (though not of the sublime description of the wonders of the heavens). Compound microscopes, though not so much to be depended upon for the purposes of discovery and philosophical investigation as single lenses, are still the best adapted for recreation”. It is hard to imagine that this was written at about the time when Robert Brown of motion fame, was discovering the celt nucleus (1831), the repository of the genetic code and thus arguably laying the foundations for all of modern biology. The sentence quoted might be taken to suggest that there was no evolutionary connection between hand lenses and compound microscopes, since as late as the 1830s the two still competed.
In trying to follow the evolution of microscopes it is trite to state that lenses had to come first. It was known for a long time that objects seen through a glass bulb full of water appeared enlarged, but the water was thought the important factor and it was not until the time of Alhazen (962-1038) that the action of a lens was understood. Roger Bacon (1242-1292) wrote “if one looks at letters and other minute things though the medium of a crystal or glass or other lens put over the letters... he will see the letters much better and they will appear much larger to him... and therefore this instrument is useful to old men and to those having feeble sight” Spectacles seem to have been invented by Salvano d'Aramento degli Arrtati of Florence who died in 1317, the secret process of how to make them being revealed by a contemporary, Alessandro della Spina of Pisa. The use of lenses in visualizing small objects made slow progress at first but eventually led to “macroscopy”, in the form of spectacles and then to microscopy.
The Transmission Confocal Laser Scanning Microscope
Authors: Carter David 
Published: March 2018

Abstract
A confocal laser scanning microscope which can collect images in both transmission and reflection modes has been installed and is being tested in the Imaging Laboratories of the John P. Roberts Research Institute, London, Ontario. Designed by Dr. Ted Dixon at the University of Waterloo, it is being developed by a multi-disciplinary research group which includes the Ontario Lasers and Lightwaves Research Centre and the Department of Physiology, University of Toronto; the Radiology, Physics, and Pathology Departments, MacMaster University; and the Zoology Department, University of Western Ontario.
Commercial confacal microscopes operate by reflectance or epifluorescence. A pair of scanning mirrors direct a diffuse laser beam in a raster pattern through an objective lens, which focuses it on the specimen. Reflected light passes back along the same light path, being “de-scanned” by the moving mirrors and then diverted by a beam splitter into a detector. On its return to the detector, light from the focal plane is focussed through a pinhole, which blocks light from out-of-focus regions of the spectrum The microscope stage is moved up and down by a stepping motor to collect images at different depths.
How Accurate is Your SEM’s Magnification?
Authors: Geller Joseph D 
Published: March 2018

Abstract
With such topics as ISO-9000, TQM (Total Quality Management) and with the Maicolm Baldridge Quality Award being mentioned these days, it may not be long before instrument calibration becomes an issue in your laboratory. Among the many important areas governed will be magnification accuracy of optical microscopes, TEMs, and SEMs, The following brief discussion probes the rather complex subject of SEM magnification accuracy.
Meconium proteins as a source of biomarkers for the assessment of the intrauterine environment of the fetus
Authors: Lisowska-Myjak B. , Skarżyńska E. , Bakun M. 
Published: March 2018

AbstractIntrauterine environmental factors can be associated with perinatal complications and long-term health outcomes although the underlying mechanisms remain poorly defined. Meconium formed exclusively in utero and passed naturally by a neonate may contain proteins which characterise the intrauterine environment. The aim of the study was proteomic analysis of the composition of meconium proteins and their classification by biological function. Proteomic techniques combining isoelectrofocussing fractionation and LC-MS/MS analysis were used to study the protein composition of a meconium sample obtained by pooling 50 serial meconium portions from 10 healthy full-term neonates. The proteins were classified by function based on the literature search for each protein in the PubMed database. A total of 946 proteins were identified in the meconium, including 430 proteins represented by two or more peptides. When the proteins were classified by their biological function the following were identified: immunoglobulin fragments and enzymatic, neutrophil-derived, structural and fetal intestine-specific proteins. Meconium is a rich source of proteins deposited in the fetal intestine during its development in utero. A better understanding of their specific biological functions in the intrauterine environment may help to identify these proteins which may serve as biomarkers associated with specific clinical conditions/diseases with the possible impact on the fetal development and further health consequences in infants, older children and adults.
Kaempferol targeting on the fibroblast growth factor receptor 3-ribosomal S6 kinase 2 signaling axis prevents the development of rheumatoid arthritis
Authors: Lee Cheol-Jung , Moon Su-Jin , Jeong Jeong-Hee , Lee Sangbae , Lee Mee-Hyun , Yoo Sun-Mi , Lee Hye Suk , Kang Han Chang , Lee Joo Young , Lee Weon Sun , Lee Hee-Jin , Kim Eun-Kyung , Jhun Joo-Yeon , Cho Mi-La , Min Jun-Ki , Cho Yong-Yeon 
Published: March 2018

AbstractRheumatoid arthritis (RA) is a systemic inflammatory disease that mainly affects the synovial joints. Although involvement of the fibroblast growth factor (FGF) signaling pathway has been suggested as an important modulator in RA development, no clear evidence has been provided. In this study, we found that synovial fluid basic FGF (bFGF) concentration was significantly higher in RA than in osteoarthritis (OA) patients. bFGF stimulates proliferation and migration of human fibroblast-like synoviocytes (FLSs) by activation of the bFGF-FGF receptor 3 (FGFR3)-ribosomal S6 kinase 2 (RSK2) signaling axis. Moreover, a molecular docking study revealed that kaempferol inhibited FGFR3 activity by binding to the active pocket of the FGFR3 kinase domain. Kaempferol forms hydrogen bonds with the FGFR3 backbone oxygen of Glu555 and Ala558 and the side chain of Lys508. Notably, the inhibition of bFGF-FGFR3–RSK2 signaling by kaempferol suppresses the proliferation and migration of RA FLSs and the release of activated T-cell-mediated inflammatory cytokines, such as IL-17, IL-21, and TNF-α. We further found that activated phospho-FGFR3 and -RSK2 were more highly observed in RA than in OA synovium. The hyperplastic lining and sublining lymphoid aggregate layers of RA synovium showed p-RSK2-expressing CD68+macrophages with high frequency, while pRSK2-expressing CD4+T-cells was observed at a lower frequency. Notably, kaempferol administration in collagen-induced arthritis mice relieved the frequency and severity of arthritis. Kaempferol reduced osteoclast differentiation in vitro and in vivo relative to the controls and was associated with the inhibition of osteoclast markers, such as tartrate-resistant acid phosphatase, integrin β3, and MMP9. Conclusively, our data suggest that bFGF-induced FGFR3–RSK2 signaling may play a critical role during the initiation and progression of RA in terms of FLS proliferation and enhanced osteoclastogenesis, and that kaempferol may be effective as a new treatment for RA.
Microscopic mechanisms of deformation transfer in high dynamic range branched nanoparticle deformation sensors
Authors: Raja Shilpa N. , Ye Xingchen , Jones Matthew R. , Lin Liwei , Govindjee Sanjay , Ritchie Robert O. 
Published: March 2018

AbstractNanoscale stress sensing is of crucial importance to biomechanics and other fields. An ideal stress sensor would have a large dynamic range to function in a variety of materials spanning orders of magnitude of local stresses. Here we show that tetrapod quantum dots (tQDs) exhibit excellent sensing versatility with stress-correlated signatures in a multitude of polymers. We further show that tQDs exhibit pressure coefficients, which increase with decreasing polymer stiffness, and vary >3 orders of magnitude. This high dynamic range allows tQDs to sense in matrices spanning >4 orders of magnitude in Young’s modulus, ranging from compliant biological levels (~100 kPa) to stiffer structural polymers (~5 GPa). We use ligand exchange to tune filler-matrix interfaces, revealing that inverse sensor response scaling is maintained upon significant changes to polymer-tQD interface chemistry. We quantify and explore mechanisms of polymer-tQD strain transfer. An analytical model based on Mori-Tanaka theory presents agreement with observed trends.
Photonic chip-based soliton frequency combs covering the biological imaging window
Authors: Karpov Maxim , Pfeiffer Martin H. P. , Liu Junqiu , Lukashchuk Anton , Kippenberg Tobias J. 
Published: March 2018

AbstractDissipative Kerr solitons (DKS) in optical microresonators provide a highly miniaturised, chip-integrated frequency comb source with unprecedentedly high repetition rates and spectral bandwidth. To date, such frequency comb sources have been successfully applied in the optical telecommunication band for dual-comb spectroscopy, coherent telecommunications, counting of optical frequencies and distance measurements. Yet, the range of applications could be significantly extended by operating in the near-infrared spectral domain, which is a prerequisite for biomedical and Raman imaging applications, and hosts commonly used optical atomic transitions. Here we show the operation of photonic-chip-based soliton Kerr combs driven with 1 micron laser light. By engineering the dispersion properties of a Si3N4 microring resonator, octave-spanning soliton Kerr combs extending to 776 nm are attained, thereby covering the optical biological imaging window. Moreover, we show that soliton states can be generated in normal group–velocity dispersion regions when exploiting mode hybridisation with other mode families.
Explosive dissolution and trapping of block copolymer seed crystallites
Authors: Guerin Gerald , Rupar Paul A. , Manners Ian , Winnik Mitchell A. 
Published: March 2018

AbstractEnhanced control over crystallization-driven self-assembly (CDSA) of coil-crystalline block copolymers has led to the formation of intricate structures with well-defined morphology and dimensions. While approaches to build those sophisticated structures may strongly differ from each other, they all share a key cornerstone: a polymer crystallite. Here we report a trapping technique that enables tracking of the change in length of one-dimensional (1D) polymer crystallites as they are annealed in solution at different temperatures. Using the similarities between 1D polymeric micelles and bottle-brush polymers, we developed a model explaining how the dissolving crystallites reach a critical size independent of the annealing temperature, and then explode in a cooperative process involving the remaining polymer chains of the crystallites. This model also allows us to demonstrate the role of the distribution in seed core crystallinity on the dissolution of the crystallites.