bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cascaded systems analysis of charge sharing in cadmium telluride photon‐counting x‐ray detectors
Authors: Tanguay Jesse , Cunningham Ian A. 
Published: March 2018

PurposeSingle‐photon‐counting (SPC) and spectroscopic x‐ray detectors are under development in academic and industry laboratories for medical imaging applications. The spatial resolution of SPC and spectroscopic x‐ray detectors is an important design criterion. The purpose of this article was to extend the cascaded systems approach to include a description of the spatial resolution of SPC and spectroscopic x‐ray imaging detectors.MethodsA cascaded systems approach was used to model reabsorption of characteristic x rays, Coulomb repulsion, and diffusion in SPC and spectroscopic x‐ray detectors. In addition to reabsorption, diffusion, and Coulomb repulsion, the model accounted for x‐ray conversion to electron‐hole (e‐h) pairs, integration of e‐h pairs in detector elements, electronic noise, and energy thresholding. The probability density function (PDF) describing the number of e‐h pairs was propagated through each stage of the model and was used to derive new theoretical expressions for the large‐area gain and modulation transfer function (MTF) of CdTe SPC x‐ray detectors, and the energy bin sensitivity functions and MTFs of CdTe spectroscopic detectors. Theoretical predictions were compared with the results of MATLAB‐based Monte Carlo (MC) simulations and published data. Comparisons were also made with the MTF of energy‐integrating systems.ResultsUnder general radiographic conditions, reabsorption, diffusion, and Coulomb repulsion together artificially inflate count rates by 20% to 50%. For thicker converters (e.g. 1000 μm) and larger detector elements (e.g. 500 μm pixel pitch) these processes result in modest inflation (i.e. ∼10%) in apparent count rates. Our theoretical and MC analyses predict that SPC MTFs will be degraded relative to those of energy‐integrating systems for fluoroscopic, general radiographic, and CT imaging conditions. In most cases, this degradation is modest (i.e., ∼10% at the Nyquist frequency). However, for thicker converters, the SPC MTF can be degraded by up to 25% at the Nyquist frequency relative to EI systems. Additionally, unlike EI systems, the MTF of spectroscopic systems is strongly dependent on photon energy, which results in energy‐bin‐dependent spatial resolution in spectroscopic systems.ConclusionsThe PDF‐transfer approach to modeling signal transfer through SPC and spectroscopic x‐ray imaging systems provides a framework for understanding system performance. Application of this approach demonstrated that charge sharing artificially inflates the SPC image signal and degrades the MTF of SPC and spectroscopic systems relative to energy‐integrating systems. These results further motivate the need for anticharge‐sharing circuits to mitigate the effects of charge sharing on SPC and spectroscopic x‐ray image quality.
Acute hypertensive stress imaged by cardiac hyperpolarized [1‐13C]pyruvate magnetic resonance
Authors: Tougaard Rasmus Stilling , Hansen Esben Søvsø Szocska , Laustsen Christoffer , Lindhardt Jakob , Schroeder Marie , Bøtker Hans Erik , Kim Won Yong , Wiggers Henrik , Stødkilde‐Jørgensen Hans 
Published: March 2018

PurposeDeranged metabolism is now recognized as a key causal factor in a variety of heart diseases, and is being studied extensively. However, invasive methods may alter metabolism, and conventional imaging techniques measure tracer uptake but not downstream metabolism. These challenges may be overcome by hyperpolarized MR, a noninvasive technique currently crossing the threshold into human trials. The aim of this study was to image metabolic changes in the heart in response to endogastric glucose bolus and to acute hypertension.MethodsFive postprandial pigs were scanned with hyperpolarized [1‐13C]pyruvate cardiac MR at baseline, after oral glucose bolus, and after infusion of angiotensin‐II.ResultsNo effect of glucose bolus was seen using hyperpolarized [1‐13C]pyruvate MR despite changes in circulating substrates. During angiotensin‐II infusion, blood pressure increased 179% (P = 0.008) and ejection fraction decreased from 54 ± 2% to 47 ± 6% (P = 0.03) The hemodynamic changes were accompanied by increases in the hyperpolarized [1‐13C]pyruvate MR derived ratios of lactate/alanine (from 0.58 ± 0.13 to 0.78 ± 0.06, P = 0.03) and bicarbonate/alanine (from 0.55 ± 0.12 to 0.91 ± 0.14, P = 0.007).ConclusionGlucose loading did not alter cardiac metabolism, but during acute hypertensive stress, cardiac aerobic, carbohydrate metabolism, and pyruvate‐lactate exchange was altered. Hyperpolarized MR allows noninvasive evaluation of acute changes in cardiac metabolism. However, hemodynamics must be taken into account when interpreting the results.
Highly accurate equilibrium structure of the C2h symmetric N1‐to‐O2 hydrogen‐bonded uracil‐dimer
Authors: Kruse Holger , Šponer Jiří 
Published: March 2018

AbstractThe highly accurate ab initio equilibrium geometry of the hydrogen‐bonded uracil dimer is derived using a composite geometry extrapolation scheme based on all‐electron, complete basis set extrapolated Møller–Plesset perturbation theory using the jun‐pwCV[T,Q]Z basis sets combined with a valence CCSD(T)/cc‐pVTZ high‐level correction. Geometrical changes on dimerization are discussed and the performance of the several density functional approximations (among others SCAN, ωB97M‐V, DSD‐PBEP86‐D3(BJ), and DSD‐PBEP86‐NL) is evaluated. Orbital‐optimized MP2.5 is discussed as a reduced‐cost alternative to the CCSD(T) gradient in the composite scheme. A new reference interaction energy is calculated with explicitly correlated F12‐CCSD(T).
Creating Pseudocolor Images using ImageJ
Authors: Sheffield Joel B 
Published: March 2018

Abstract
It is common for microscopists to examine fluorescent samples that have been exposed to a mixed set of fluorophores with specific staining properties. Images are often captured from these samples as a set, using different filter sets to isolate specific elements of the sample. Sometimes the images are captured in gray scale, and in other cases, they are captured with color cameras. In either case, one would often like to combine the images to create a single image that presents the information from all fluorophores at once. This kind of display is particularly useful for determining the relative locations of different components.
Nanoparticle Visualization with an AFM
Authors: West Paul , Starostina Natasha 
Published: March 2018

Abstract
It is often said that: “…a picture is worth a thousand words… ” This can be certainly true for images from an Atomic Force Microscope.
Although we often know that nanoparticles exist and we have a mental picture of what they look like, it is often helpful to be able to “see” the particles to verify that they are morphologically what we imagine they are. When the particles are much less than a micron in diameter, they cannot be directly visualized with an optical microscope. At best, sub micron particles appear as “diffraction spots” in an optical microscope. It is possible to visualize nanoparticles with SEM or TEM.
Protect Your Detectors
Authors: Michael Stanley C 
Published: March 2018

Abstract
Excessive light to detectors can be very harmful. Too much light, either monochromatic or wide band, can easily destroy photomultiplier tubes (PMTs). Charge-coupled devices (CCDs) cameras, of modern design, are typically made with cut-outs so that saturation beyond several pixels will cause them to shut off. Unfortunately, the detectors in the back of your eyes do not have automatic shut-off mechanisms, and can be easily destroyed with excessive light.
As a review of filters and cubes, keep in mind that the primary job for the excitation filter is to block all light other than the desired band being used to excite the fluorochrome. The primary job of the emission filter is to block the excitation source. If these two optics are chosen correctly and inserted in the beam path, the only light reaching the detector is the fluorescence emission from the fluorochrome. Nothing from the source should make it to the detector. This very weak emission intensity has no chance of harming the detectors. If these two optics are not perfectly matched, the excitation light may reach the detector and cause all sorts of problems.
Digital Image Tips: Adjusting Brightness And Contrast In Micrographs Using Adobe PhotoshopÆ
Authors: Johnson Bradley R 
Published: March 2018

Abstract
Recently on the microscopy list server, a question came up as to how to compensate for charging in SEM micrographs. Several good answers were suggested. Some of them were 1) recoating the sample to prevent the build up of charge on the sample in the first place, and image it again, 2) use an environmental SEM (ESEM) in the “wet” mode to eliminate the charging phenomena, 3) use a different detector, such as a backscattered electron detector, which is much less sensitive to charging phenomena, and 4) apply adjustments to the digital image using software such as Adobe PhotoshopÆ to minimize the effect of the charging problem.
Applicability of Freeze-Fracture and Cryo-TEM to Complex Liquids
Authors: Burns Janet L , Spontak Richard J 
Published: March 2018

Abstract
Traditional methods of sample preparation and analysis in conventional transmission electron microscopy (TEM) are not readily applicable to multicomponent complex liquids which may contain a wealth of microstructural information. Two techniques which facilitate the study of structure in such liquids are freeze-fracture (FF) TEM and cryo-TEM.
Microscopy Reveals Early Neolithic Dentistry
Authors: Carmichael Stephen W 
Published: March 2018

Abstract
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.
Why Pressure Scales Cause So Much Confusion
Authors: Buonaquisti Anthony D 
Published: March 2018

Abstract
Pressure scales can be extremely confusing to new operators. This is not surprising. To my mind, there are three primary areas of confusion.
Firstly, the pressure of gas inside an instrument changes over many orders of magnitude during pump-down. The change is about 9 orders of magnitude for a traditional Scanning Electron Microscope and about 13 orders of magnitude for an ultra-high vacuum instrument such as a Scanning Auger Microprobe.
Towards Optimal Imaging and Microanalysis in Variable Pressure and Low Voltage SEM
Authors: Griffin Brendan J 
Published: March 2018

Abstract
Image quality of 'secondary electron imaging' has been an ongoing operational issue with the variable pressure range of scanning electron microscopes (VPSEM), including the extended pressure range environmental or SEM. A second question that has received considerable attention concerns charge cancellation on insulators in VPSEM with particular reference to effects of charging on x-ray microanalytical results.
Digital Scanning, Archiving, and Transmitting Electron Micrographs
Authors: Cartwright Joiner 
Published: March 2018

Abstract
The primary responsibility of the clinical electron microscopy laboratory is to produce, and deliver to the pathologist or clinician, high quality ultrastructural images of pathological specimens in a timely manner. In order to facilitate this process, medical EM labs are converting from traditional chemical processing of photographic film and paper to the acquisition and transmission of electron images by computer. Ideally the electron microscope would incorporate a digital camera in the column to collect the images, thus bypassing chemical processing of film and paper altogether. However, due mainly to the high cost of the in-column cameras, many labs continue to use film, but replace the time consuming enlarging/printing in the darkroom with digital techniques at the computer.
"Objects Worthy of Notice" Microscopical Anatomy of Selected Plants Collected by The Lewis & Clark Expedition
Authors: Alden Harry A , Cunningham Roland H , Ryan Kevin , Jantzen Paul T , Dobbins David R 
Published: March 2018

Abstract
Plants that are used for taxonomic research are generally preserved by drying them out while they are being pressed flat for easy storage. This pressed plant material, is placed in a herbarium, in phylogenetic order, based on the species, genus, family and order designations.
Herbaria are essential for the study and verification of plant classification, the study of geographic distributions, and the standardizing of taxonomic nomenclature. Lately, herbarium materials have been utilized in biochemical and genetic studies. The key to these studies is the state of preservation of the plant material. The preservation of the reproductive and vegetative structures (hairs, stomata, cuticle, etc.), internal anatomy (vascular tissue size and arrangement), biochemistry and genetic material is essential to make accurate observations, to collect representative data and answer pertinent research questions.
Correlating Fluorescence Microscopy with Electron Microscopy
Authors: Carmichael Stephen W , Charlesworth Jon 
Published: March 2018

Abstract
The use of fluorescent probes is becoming more and more common in cell biology. It would be useful if we were able to correlate a fluorescent structure with an electron microscopic image. The ability to definitively identify a fluorescent organelle would be very valuable. Recently, Ying Ren, Michael Kruhlak, and David Bazett-Jones devised a clever technique to correlate a structure visualized in the light microscope, even a fluorescing cell, with transmission electron microscopy (TEM).
Two keys to the technique of Ren et al are the use of grids (as used in the TEM) with widely spaced grid bars and the use of Quetol as the embedding resin. The grids allow for cells to be identified between the grid bars, and in turn the bars are used to keep the cell of interest in register throughout the processing for TEM. Quetol resin was used for embedding because of its low auto fluorescence and sectioning properties. The resin also becomes soft and can be cut and easily peeled from glass coverslips when heated to 70°C.
Comments on Cryo High Resolution Scanning Electron Microscopy
Authors: Apkarian Robert P 
Published: March 2018

Abstract
Stephen Carmichael wrote about Cryoelectron Tomography in the May 2003 issue of Microscopy Today. Citing new preparation methods, small cells can be vitrified, observed frozen in the TEM and a series of digital images captured while the specimen is being rotated around the axis perpendicular to the electron beam producing a 3-D tomogram. Gina Sosinski and Maryann Martone wrote about imaging big and messy biological structures using cryo-electron Tomography in the July issue of Microscopy Today. Cryo-HRSEM now also seeks to provide 3-D information approaching the molecular level from frozen hydrated cell and molecular systems. Vitrification procedures for small specimens such as platelets and biomolecules on grids are accomplished by plunge freezing in liquefied etiiane as is done with cryo-TEM procedures. Bulk specimens such as organic hydrogels and tissues are routinely high pressure frozen (HPF) in 3mm gold planchets. Employing an in-lens cryostage, identical to those used in cryo-TEM, cryo-HRSEM provides 3-D high-resolution images because secondary electrons are efficiently collected above the lens in a single scan thus minimizing specimen irradiation.
New Adhesion Mechanism in Giardia: Role of the Ventrolateral Flange in the Attachment of Trophozoites to Rough and Porous Surfaces
Authors: Erlandsen SL , Russo AP , Turner JN 
Published: March 2018

Abstract
The protozoan parasite Giardia, an intestinal flagellate, has evolved an unique attachment organelle called the ventral adhesive disk (VAD). This attachment organelle mediates attachment of the trophozbite to the microviUous border (MVB) of intestinal absorptive cells, and production of lesions via attachment are thought to lead to diarrheal disorder characteristic of giardiasis. The VAD has contractile proteins arranged around it's circumference and it has been suggested that contraction of this area might function like a purse-string suture. The resemblance of the VAD to a suction cup has led to the hypothesis that suction or a negative pressure produced under the VAD by a grasping action might produce the adhesive force regulating attachment. To test whether or not the generation of a negative pressure is necessary for attachment, experiments were designed in which the substratum was fabricated to have an uneven surface, or the substratum was composed of different arrangement of pores.
Membrane Leftovers after Fusion of Vacuoles
Authors: Carmichael Stephen , McNiven Mark 
Published: March 2018

Abstract
In a clever application of time-lapse fluorescence microscopy, Li Wang, Scott Seeley, William Wickner, and Alexey Merz looked to see if there was membrane left over after vacuoles fused within a cell. Specifically, It is not known what happens when two vacuoles come together (this is referred to as “docking” ) and join together as one larger vacuole (“fusion“). For reference, the surfaces of the vacuoJes where they have joined is the “boundary” membrane, the membranes on the outside are the “outside” membranes, and the circular junction of the boundary and outside membranes is the “vertex.“
Photoshop™ Tutorials Selecting ROIs from Brightfield Images
Authors: Sedgewick Jerry 
Published: March 2018

Abstract
This column is, perhaps, a departure from many techniques papers because the accompanying image chosen as “representative“ really is representative, rather than what is seen in many published papers in which the representative image is the one perfect image among hundreds of those that are biologically messy. The image used in this article to illustrate methods is not the best to use when creating regions of interest with Photoshop toots, for it contains elements which make the separation into regions of interest difficult to accomplish without reacquiring the image using better microscope techniques. I'm assuming that an image of this sort CAN bereacquired; if that isn't possible, some head-scratching and, perhaps a shift from a position of absolute accuracy to statistical accuracy might occur, and many would argue, should occur (since the whole matter is statistical anyway). Hopefully the investigator understands that, in some instances, human error can be as confounding as image processing error, except that image processing can create consistency. In other instances, artifacts in the images themselves cart cause too many wrong features to be measured, leaving humans as the best instrument.
When is a Microscope MORE than a Microscope?
Authors: Piano Robert J , Leckenby Jezz 
Published: March 2018

Abstract
Traditionally the field of microscopy has centered on the creation of highly magnified images of things too small to be seen with the eye alone. This was certainly the case with scanning probe microscopy, which burst on to the scene some 15 years ago with dramatic images of individual atoms. We are visual beings and the rapid acceptance of SPM followed directly from its ability to represent physical interactions in an intuitive image format. However, much of the vaiue of SPM today derives from its ability detect and measure a wide variety of specific interactions between its scanning probe and the sample. As the technology continues to mature, emphasis is shifting from its ability to display these signals as images to its ability to quantify and measure them.
Microwave Immunohistochemistry On Mohs Cryostat Sections
Authors: Miller Diane G 
Published: March 2018

Abstract
With the advent of Mohs surgery in the dermatology clinics, making sure the margins are clear of any cancer is of the utmost importance to both patient and dermatopathologist. While the patient is stiil in the surgery suite, immunohistochemistry staining can be done in the laboratory microwave (Pelco microwave with waiter load cooler wattage controller arid temperature probe). The immunohistochemistry procedure takes only 25-30 minutes as compared to the more conventional methods that take 2 hours or more.
The microwave needs to be checked for hot spots using the Pelco #36140 microwave bulb array. Make sure the area in which you are going to put your slides has no hot spots, indicated by no illuminating bulbs. Using a Sigma Diagnostics #H6644 Humid Chamber; place a paper towel in the bottom of the chamber and fill with 1/4 inch of water.
Taking Correlative Microscopy to a New Level
Authors: Carmichael Stephen W 
Published: March 2018

Abstract
We are all familiar with the concept of correlating an image acquired by light microscopy (LM) with one obtained by transmission electron microscopy (TEM). This allows us to take advantage of the “wide angle” view of LM and the high resolution of TEM. Correlative microscopy has been taken to a new level by Alvin Lin and Cynthia Goh who have designed a clever device. This device allows repetitive correlative microscopy between TEM and atomic force microscopy (AFM).
A New Capability for Light Microscopes: Mid infrared Molecular Analysis
Authors: Rein Alan J 
Published: March 2018

Abstract
The merger of molecular spectroscopy with microscopy is certainly not a new concept. Microscope attachments for FT-IR spectrometers have been available for nearly two decades and there are literally thousands of FT-IR spectrometers with these devices currently installed. The vast majority of them are applied to contaminant or forensic oriented problems. As such, the microscopes are often used as sophisticated beam condensers, enabling the spectrometer to focus infrared radiation on the samples that are typically larger than 10 microns.
M&M 2002: Core Facility Management Session Maintaining Major Equipment in the Core Microscopy Facility
Authors: Sherman Debby 
Published: March 2018

Abstract
D. Sherman: This session centers on approaches to maintaining major equipment—primarily electron microscopes. I thought we ought to look at how effective it is to seivice with onsite engineers. So with that I would like to start us out with Pat McGinley from JEOL.
Pat is a long—time JEOL employee. He started out as a service engineer in 1976 and is currently Vice President of Service and a member of the Board of Directors for JEOL USA.
Adding Color to Grayscale Images
Authors: Sedgewick Jerry 
Published: March 2018

Abstract
In the world of fluorescent imaging, the need to colorize grayscale images can be an everyday task. Yet, when all too many of these colorized images go to publication, the results appear to contain undifferentiated blobs of a saturated color, rather than images that contain gradations of color.
While very small objects need to be as bright as possible in order to make these objects apparent (e.g. bacteria under low magnification), and while too many push the gain on photomultiplier tubes in order to top grayscale values off at 255 (on an 8-bit range) in order to show unquestionable colocalization, only the former can be defended on the basis of revealing lost features.