bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interactive simulation of high-resolution electron micrographs
Authors: Kilaas Roar 
Published: June 2020

Only a few years ago image simulation of HRTEM images were mostly carried out as low priority jobs on large mainframe computers with images available the next day as overprinted characters on computer paper. Today the same calculation can be carried out on a dedicated workstation in a matter of minutes with output on high resolution video monitors. This improvement in computer hardware has produced a shift from software primarily designed to run as batch jobs to interactive software that allows instant changes to both the atomic model and microscope parameters. In these near “real time” calculations the user interface becomes an important part of the software, since setting up the conditions for the calculation may take longer than the calculation itself.In an attempt to create a truly interactive environment for simulation of HRTEM images, a new set of programs has been written at the National Center for Electron Microscopy (NCEM) at Berkeley.
Interphase interfaces in Nio-Zro2 (Cao) eutectic
Authors: Dravid Vinayak P. 
Published: June 2020

Directionally solidified eutectics (DSEs) of oxide-oxide components offer many advantages over the conventional bi-crystal specimens for interface studies. The two phases in the DSE grow in unison with a well-defined orientation relationship and offer a wide spatial range of crystallographically similar interfaces. A preliminary investigation has been carried out to characterize interphase interfaces in the DSE system NiO-ZrO2 (CaO). The transverse section of the DSE consists of alternate lamellae of cubic NiO and CaO-stabilized cubic ZrO2, as shown in Figure 1. The orientation relationship (OR) from the selected area diffraction (SAD) pattern (Figure 2) was observed to be:growth direction //[011]NiO//[001]ZrO2 and
interfacial plane //(111)NiO//(100)Zr02The above OR was predominant in the bulk material and is consistent with x-ray results, but at lamellar termination/faults the OR was observed to be:
Cryoultramicrotomy and the cryofixation of polymers
Authors: Cieslinski R. C. , Marshall J. G. 
Published: June 2020

The recent development of ductile polymer blends and emulsion polymers has necessitated the adaptation of cryogenic methods, frequently used in biomedical microscopy, to the study of bulk polymers.The use of cryogenic methods offers the polymer microscopist some advantages over more conventional staining techniques. It is possible to retain morphology without distortion in ductile materials such as polyethylene, polypropylene, and blends with soft components. There is no chemical alteration of the material which is usually a requirement of electron diffraction energy dispersive spectrometry, and electron energy loss spectrometry, Preparation artifacts are generally minimal. Figure 1 shows butyl acrylate rubber/styrene acrylonitrile blend stained with a RuO4 solution. Although less contrast is achieved, the cryo-sections show that the staining solution has caused the rubber domains to expand in size (Fig. 2).
Histogenesis of alveolar cell carcinoma
Authors: Rybicka Krystyna 
Published: June 2020

Alveolar cell carcinoma (ACC) is a lung neoplasm characterized by the presence of lamellar bodies specific for normal type 2 alveolar cells. Tumor histogenesis is uncertain. The present study indicates that ACC originates from dedifferentiation of hyperplastic type 2 alveolar cells rather than migration of bronchial stem cells into alveoli as suggested earlier.An aliquot of human lung biopsy diagnosed as ACC was fixed in glutaraldehyde and osmium, treated with 1% aqueous uranyl acetate, and embedded in epoxy resin. Sections were stained for glycogen by periodic acid - thiosemicarbazide - silver proteinate, and post-stained by uranyl acetate and lead citrate.The tumor contained morphologically distinct cell clusters. Each cluster consisted of identical cells. Differences between clusters resulted from synchronous alterations in lamellar bodies, mitochondria, glycosomes, and ribosomes. These alterations revealed distinct stages in cell differentiation classified here as follows: stage 1-hyperplastic cells (Fig.1), stage 2-dedifferentiating cells (Fig.2), stage 3-undifferentiated cells (Fig.3), stage 4-differentiating cells (Fig.4).
Parathyroid gland before and after cisplatin treatment
Authors: Aggarwal S.K. , Fadool J.M. 
Published: June 2020

Cisplatin (CDDP) a potent antitumor agent suffers from severe toxic side effects with nephrotoxicity being the major dose-limiting factor, The primary mechanism of its action has been proposed to be through its cross-linking DNA strands. It has also been shown to inactivate various transport enzymes and induce hypocalcemia and hypomagnesemia that may be the underlying cause for some of its toxicities. The present is an effort to study its influence on the parathyroid gland for any hormonal changes that control calcium levels in the body.Male Swiss Wistar rats (Crl: (WI) BR) weighing 200-300 g and of 60 days in age were injected (ip) with cisplatin (7mg/kg in normal saline). The controls received saline injections only. The animals were injected (iv) with calcium (0.5 ml of 10% calcium gluconate/day) and were killed by decapitation on day 1 through 5. Trunk blood was collected in heparinized tubes.
Immunogold labeling of CMP-KDO synthetase produced by recombinant E. Coli cells
Authors: Durum F. A. , Goldman R. G. , Bolling T. J. , Miller M. F. 
Published: June 2020

CMP-KDO synthetase (CKS) is an enzyme which plays a key role in the synthesis of LPS, an outer membrane component unique to gram negative bacteria. CKS activates KDO to CMP-KDO for incorporation into LPS. The enzyme is normally present in low concentrations (0.02% of total cell protein) which makes it difficult to perform large scale isolation and purification. Recently, the gene for CKS from E. coli was cloned and various recombinant DNA constructs overproducing CKS several thousandfold (unpublished data) were derived. Interestingly, no cytoplasmic inclusions of overproduced CKS were observed by EM (Fig. 1) which is in contrast to other reports of large proteinaceous inclusion bodies in various overproducing recombinant strains. The present immunocytochemical study was undertaken to localize CKS in these cells.Immune labeling conditions were first optimized using a previously described cell-free test system. Briefly, this involves soaking small blocks of polymerized bovine serum albumin in purified CKS antigen and subjecting them to various fixation, embedding and immunochemical conditions.
Designing high-resolution slow scan CCD-based TEM camera systems
Authors: Mancuso James F. , Maxwell William B. , Camp Russell E. , Ellisman Mark H. 
Published: June 2020

The imaging requirements for 1000 line CCD camera systems include resolution, sensitivity, and field of view. In electronic camera systems these characteristics are determined primarily by the performance of the electro-optic interface. This component converts the electron image into a light image which is ultimately received by a camera sensor.Light production in the interface occurs when high energy electrons strike a phosphor or scintillator. Resolution is limited by electron scattering and absorption. For a constant resolution, more energy deposition occurs in denser phosphors (Figure 1). In this respect, high density x-ray phosphors such as Gd2O2S are better than ZnS based cathode ray tube phosphors. Scintillating fiber optics can be used instead of a discrete phosphor layer. The resolution of scintillating fiber optics that are used in x-ray imaging exceed 20 1p/mm and can be made very large. An example of a digital TEM image using a scintillating fiber optic plate is shown in Figure 2.
Unattended automated elemental analysis of fibrous and non-fibrous inorganic particulates
Authors: Sheehan CE , Emerson RJ , Mastovich JM , Singh JK , Ross JS 
Published: June 2020

Automated identification and analysis of inorganic particulates by Scanning Electron Microscopy (SEM) and energy dispersive x-ray analysis (EDX) has been established for many years. Our laboratory has developed and refined a procedure for unattended automated analysis which significantly increases the number of particles analyzed per hour and dramatically decreases the analyst's time spent at the microscope.The sample is analyzed in a JEOL JSM 6100 scanning electron microscope (JEOL, Inc, Peabody MA) integrated by Sesame (Fisons Instruments, Inc, San Carlos, CA) with a Kevex Quantum Delta Class energy dispersive x-ray spectrometer (Fisons Instruments, Inc, San Carlos, CA). Working within the software program Automated Image Analysis (AIA), our user-defined sequence of commands or procedure file is created. This procedure combines digital imaging and features analysis, x-ray analysis and integrated Sesame stage control.Beginning with the field of choice, the procedure file is initiated by the operator, the image on the microscope is acquired onto the computer screen, a binary image is created, and features (particles) are processed (identified) followed by analysis of each particle for elemental composition.
Microprobe analysis in clinical diagnosis
Authors: Shelburne J. D. , Roggli V. L. , Ingram P. 
Published: June 2020

In addition to providing an important and unique analytical tool for medical and biological research, the findings from microprobe analysis often have diagnostic, therapeutic and/or legal significance for patients. References cited below provide a guide to this expanding literature.Of the various types of microanalysis available, electron probe microanalysis is at present the most useful for clinical studies. Backscattered electron imaging is used as a guide to identify relatively high atomic number inclusions in the relatively low atomic number background of human tissue. Correlation of the backscattered electron images with the images obtained through conventional light microscopy is an absolutely critical aspect of these studies. For better or for worse, the “gold standard” of current medical practice remains the light microscopic examination of conventionally stained (e.g. hematoxylin and eosin) paraffin sections. Accordingly, it is necessary that the microprobe data can ultimately be ascribed to particular features of the conventional images well understood by pathologists.
Structure determination using convergent-beam electron diffraction
Authors: Steeds J W , Vincent R 
Published: June 2020

There are many different approaches in quantitative electron diffraction which are being vigorously pursued at present. The approach we adopt is based on the insights provided by the Bloch-wave formulation of dynamical electron diffraction theory into the physics of dynamical scattering. This insight is used to select diffraction situations where a pseudo-kinematical approximation may be made. A forwards route is then possible directly from the experimental observations to the structural implications. This contrasts with the model-building, multi-parameter fitting procedures used in many other approaches where a problem of uniqueness inevitably arises.Because the pseudo-kinematical approach ignores many of the detailed dynamical interactions which occur locally over small angular ranges we do not attempt to make accurate measurements, and wherever possible average (visually at least) along Bragg lines to eliminate local perturbations. In a sense the work resembles early X-ray crystallography where reflections were put in one of six or so classes from very weak to very strong.
Electron energy-loss near-edge structure in silicate minerals
Authors: McComb D W , Payne R S , Hansen P L , Brydson R 
Published: June 2020

Electron energy-loss near-edge structure (ELNES) is an effective probe of the local geometrical and electronic environment around particular atomic species in the solid state. Energy-loss spectra from several silicate minerals were mostly acquired using a VG HB501 STEM fitted with a parallel detector. Typically a collection angle of ≈8mrad was used, and an energy resolution of ≈0.5eV was achieved.Other authors have indicated that the ELNES of the Si L2,3-edge in α-quartz is dominated by the local environment of the silicon atom i.e. the SiO4 tetrahedron. On this basis, and from results on other minerals, the concept of a coordination fingerprint for certain atoms in minerals has been proposed. The concept is useful in some cases, illustrated here using results from a study of the Al2SiO5 polymorphs (Fig.l). The Al L2,3-edge of kyanite, which contains only 6-coordinate Al, is easily distinguished from andalusite (5- & 6-coordinate Al) and sillimanite (4- & 6-coordinate Al). At the Al K-edge even the latter two samples exhibit differences; with careful processing, the fingerprint for 4-, 5- and 6-coordinate aluminium may be obtained.
Hydrated Specimen Stability in the Electroscan ESEM: Specimen Surface Temperature Variations and the Limitations of Specimen Cooling
Authors: Griffin Brendon J. 
Published: June 2020

Chamber temperature and pressure are the two principal factors in preserving hydrated specimens in a high vapour pressure or environmental SEM; in this study the Electroscan ESEM. Hydrated specimen stability, is achieved by operating at or near water saturated conditions in the specimen chamber.The ambient chamber temperature (in the ESEM) has been measured and found to be ∼29°C, ∼7°C higher than the laboratory environment. Water saturation at this temperature requires a chamber pressure of ∼30t and poor image resolution results from the high degree of primary beam scattering under these conditions. A low cost Peltier effect cooling stage has been constructed to provide cooling of specimens to ∼5°C. At this temperature water saturated conditions are achievable in the chamber at ∼5t with resultant good image resolution.Usage has shown that stability of sensitive hydrated specimens still remains difficult. This is due to the cooling and measurement of specimen temperature through the stage at the base of the specimen, rather than at the surface.
Prospects for compositional imaging with the atom probe microscope
Authors: Kelly T. F. , Camus P. P. , McCarthy J. J. , Larson D. J. , Holzman L. M. , Zreiba N. A. 
Published: June 2020

For the purposes of analytical characterization on the atomic scale, the ultimate instrument would identify every atom in a sample and determine its position with atomic-scale resolution. The recently developed positionsensitive atom probe (POSAP) comes as close as yet possible to this goal. This is the only experimental technique which can analyze the three-dimensional (3D) composition of a sample on a sub-nanometer scale.By adding a position-sensitive detector (PSD) to a conventional atom probe/field ion microscope, a 3D data structure with position-correlated compositional analysis is acquired. The 3D data are stored on a computer and may be examined for structural and compositional information at an atomic level. Note that, because it uses time-of-flight mass spectroscopy, all elements and their isotopes are detected in this way with equal proficiency. Usually, the evaporation rate is mediated by pulsing the field on the specimen. This approach, however, severely limits the data acquisition rate (about 1 atom per second) and mass resolution (about 1 part in 30).
The genetic relationship between hydrous and anhydrous interplanetary dust particles
Authors: Zolensky Michael , Barrett Ruth 
Published: June 2020

It is a fundamental goal of interplanetary dust particle (IDP) research to determine the sources and histories of these primitive extraterrestrial materials. Chondritic IDPs have been divided into anhydrous and hydrous varieties, with sub-classification being made on the grounds of the dominant anhydrous (olivine or pyroxene) or hydrous (smectite or serpentine) present. The presumption is that hydrated IDPs experienced aqueous alteration on parent bodies (hydrous asteroids or possibly comets); we wish to discover whether the anhydrous IDPs were the initial raw materials for these reactions. We report here analyses of olivines and pyroxenes from 22 large (>15 um) chondritic IDPs: 18 anhydrous and 4 hydrous; olivines and pyroxenes are scarce in most hydrous IDPs, when present at all Finally, we compare anhydrous to hydrous IDPs, and both to chondritic meteorites.Figure 1 shows our results for this study. We find there to exist no significant difference in the compositions of olivines from olivine vs. pyroxene dominated IDPs, which are therefore plotted together (in contrast to our preliminary results for a smaller data set).
A preliminary study of a high-Na glass and its Cl-rich inclusions by EPMA
Authors: Yang S. V. , Wagstaff J. H. , McKay G. A. 
Published: June 2020

It is always a challenging task for the probe user to handle the Na-loss problem of high sodium glasses in EPMA (electron probe microanalysis). To find an appropriate Cl-bearing EPMA standard is another challenge, too. Here we adopted the analytical methods suggested by Yang, et. al., to meet both challenges for our study of a unique glass (Sample C9) from the Lonar Crater, India. The main object of this study is to explore an old field (Na loss) and a new field (standardless WDS analysis) in EMPA. Therefore, we will not discuss the geological implications of the analysis results in detail.Glass C9 contains more than 95% glass matrix plus a few percent inclusions. The majority of the inclusions in the glass matrix are feldsparthoid-like clusters 100-200 microns in size (Figure 1). Pyrite-like dissimilates less than 1 micron are also common. The glass is a quenched impact melt formed when a meteorite struck an evaporite-rich target area.
Small-area-x-ray fluorescesce analysis of multilayer thin -metal- films
Authors: Zaitz M. A. 
Published: June 2020

Thin film technology has become an integral part of semiconductor multichip ceramic packages. Characterizing the thickness of multimetal thin film structures that combine both thin and thick films is an important parameter for manufacturing process control and development.Statistical process control (SPC) is a new requirement for manufacturing processes. Cost is also becoming a crucial factor. "State of the art" multichip ceramic packages built to many levels of thin films are expensive. The fewer parts sacrificed for testing using the standard destructive analytical techniques the more cost effective is the process. Small area, non-destructive thickness measurements on actual product are a must for today and will be even more significant in the future as patterns are reduced in size. Creative and innovative instrumentation and techniques are needed to keep pace with the changing technology. The new and novel micro XRF technique is meeting the challenge "head on".Traditional micro analysis techniques such as SEM-EDX and microprobe involve altering the sample, i.e.
Microbeam x-ray diffraction and its applications in the semiconductor industry
Authors: DeHaven Patrick W. 
Published: June 2020

X-ray diffraction(XRD) from polycrystalline materials is a powerful structural probe, capable of obtaining information on phase(s), crystallite orientation, average grain size, and residual stress. One problem in the application of XRD to the analysis of semiconductor chips and multi-chip carriers is that there is often the need to obtain information from individual features, which can range in size from several hundred microns on chip carriers to sub-micron on semiconductor devices. Conventional powder diffractometers are designed to irradiate an area of several square millimeters, and cannot be used to examine individual micron-sized features. This need to obtain diffraction information from very small areas has been one of the driving forces behind the development of x-ray microbeam diffraction.The design of a microdiffractometer involves modification of the incident x-ray beam, the sample holder, and the x-ray detector. The incident beam must be focused down to a spot size consistent with the feature to be examined.
Interface Between a Gatan PEELS and an EDAX 9900 Computer for Simultaneous Energy Loss Analysis and Chemical Mapping
Authors: Thomas X. , Balossier G. , Wagner D. , Martin Ph. , Bonhomme P. 
Published: June 2020

IntroductionEnergy loss spectroscopy is a well known technique allowing elemental analysis in thin films. When an energy loss spectrometer is coupled with a STEM it is possible in addition to perform chemical mapping. The U314 INSERM laboratory is equipped with a C.M. 30 PHILIPS STEM coupled with an EDAX 9900 and a GATAN 666 parallel detection electron spectrometer.We describe a complete system including an additional A.T. microcomputer enabling simultaneous energy loss analysis and chemical mapping .Material and methodAn interface fitted with the bus connecting the GATAN electronics and the EDAX multichannel analyzer (MCA) allows to read the data during a photodiode read-out, and to send them via a parallel port into the host A.T microcomputer. To do this, only 18 bus lines are used and the proprietary communication protocol between the photodiode interface and the MCA is not affected. All the functions provided by the EDAX PVEELP software are preserved.
The Detection of 0.5AT% Boron in Ni3Al Using Parallel Energy Loss Spectroscopy
Authors: Boothroyd C B , Sato K , Yamada K 
Published: June 2020

Recent work has suggested that the improvement in ductility when boron is added to the inherently brittle Ni3Al is caused by the segregation of boron to the grain boundaries and that this seems to be associated with the presence of disordered grain boundary “phases”. In order to clarify the role of boron at Ni3Al boundaries at the resolution of transmission electron microscopy we have developed a method for detecting concentrations as low as 0.5at% of boron in Ni3Al using parallel energy loss spectroscopy.Specimens of Ni-24at%Al with and without 0.5at% B were electropolished in a 20% perchloric acid/ethanol solution and examined at 120 kV in a Philips 420T electron microscope equipped with a Gatan parallel energy loss spectrometer. Figure la shows part of the loss spectrum from the Ni3Al-0.5%B matrix after background subtraction. Provided a high enough count rate can be obtained, the major problem for detecting small edges in energy loss spectra is channel to channel variations in the gain, which for figure la produce a noise level (2σ) of ~0.3%.
Stepped Diffractor for Point Focusing of Monochromatic X RAYS
Authors: Wittry David B. , Sun Songquan 
Published: June 2020

Point focusing x-ray diffractors can be obtained by a geometry that corresponds to rotating the Johansson geometry about a line joining the source and image points. Methods by which such a diffractor can be made from bulk single crystal materials have been previously described. In the present paper, we consider the design of a diffractor with a stepped surface that could utilize layered diffracting materials such as multiple monomolecular films or layered synthetic microstructure (LSM). First we consider the effect of the diffractor material's rocking curve on the performance in focusing diffractors. Then we consider limitations on the focusing that arise from the width of the rocking curve and the finite size of the steps, and we give an example of the design parameters of a point focusing diffractor with stepped surface.Effect of The Rocking Curve. Width For diffractors used in focusing applications, it is important to know the physical basis for the rocking curve in order to determine whether the width of the rocking curve will affect the angle of diffraction.