bluuebunny/crossref_metadata_2025 huggingface dataset:
The Material Theory of Induction at the Frontiers of Science
Authors: Peden William
Published: July 2020

According to John D. Norton's Material Theory of Induction, all reasonable inductive inferences are justified in virtue of background knowledge about local uniformities in nature. These local uniformities indicate that our samples are likely to be representative of our target population in our inductions. However, a variety of critics have noted that there are many circumstances in which induction seems to be reasonable, yet such background knowledge is apparently absent. I call such an absence of circumstances ‘the frontiers of science', where background scientific theories do not provide information about such local uniformities. I argue that the Material Theory of Induction can be reconciled with our intuitions in favour of these inductions. I adapt an attempted justification of induction in general, the Combinatoric Justification of Induction, into a more modest rationalisation at the less foundational level that the critics discuss. Subject to a number of conditions, we can extrapolate from large samples using our knowledge of facts about the minimum proportions of representative subsets of finite sets. I also discuss some of Norton's own criticisms of his theory and argue that he is overly pessimistic. I conclude that Norton's theory at least performs well at the frontiers of science.
Respect for Subjects in the Ethics of Causal and Interpretive Social Explanation
Authors: FRAZER MICHAEL L.
Published: July 2020

Rival causal and interpretive approaches to explaining social phenomena have important ethical differences. While human actions can be explained as a result of causal mechanisms, as a meaningful choice based on reasons, or as some combination of the two, it is morally important that social scientists respect others by recognizing them as persons. Interpretive explanations directly respect their subjects in this way, while purely causal explanations do not. Yet although causal explanations are not themselves expressions of respect, they can be used in respectful ways if they are incorporated into subjects’ self-directed projects. This can occur when subjects correctly understand and freely adopt researchers’ goals through a process of informed consent. It can also occur when researchers correctly understand and adopt their subject’s goals, using their research to empower those they study.
Food-Based Dietary Guidelines – development of a conceptual framework for future Food-Based Dietary Guidelines in Europe: report of a Federation of European Nutrition Societies Task-Force Workshop in Copenhagen, 12–13 March 2018
Authors: Tetens Inge , Birt Christopher A. , Brink Elizabeth , Bodenbach Stephanie , Bugel Susanne , De Henauw Stefaan , Grønlund Trine , Julia Chantel , Konde Åse Bonde , Kromhout Daane , Lehmann Undine , dos Santos Quenia , Sokolovic Milka , Storcksdieck genannt Bonsmann Stefan , van Rossum Caroline , Boeing Heiner
Published: July 2020

Identifying a need for developing a conceptual framework for the future development of Food-Based Dietary Guidelines (FBDG) in Europe, The Federation of European Nutrition Sciences established a Task Force for this purpose. A workshop was held with the specific objective to discuss the various dimensions considered as particularly relevant. Existing frameworks for FBDG were discussed, and presentations from various countries illustrated not only several commonalities but also a high degree of heterogeneity in the guidelines from different countries. Environmental aspects were considered in several countries, and dimensions like food safety, dietary habits and preparation were included in others. The workshop provided an overview of the use of FBDG – both in developing front-of-pack nutrition labels and for reformulation and innovation. The European FBDG dimensions were described with examples from the close connection between FBDG and European Union (EU) policies and activities and from the compilation of a database of national FBDG. Also, the challenges with communication of FBDG were discussed. Considering the current scientific basis and the experiences from several countries, the Task Force discussed the various dimensions of developing FBDG and concluded that environmental aspects should be included in the future conceptual framework for FBDG. A change in terminology to sustainable FDBG (SFBDG) could reflect this. The Task Force concluded that further work needs to be done exploring current practice, existing methodologies and the future prospects for incorporating other relevant dimensions into a future Federation of European Nutrition Societies conceptual framework for SFBDG in Europe and working groups were formed to address that.
The psychological impact of COVID-19 pandemic on medical staff in Guangdong, China: a cross-sectional study
Authors: Wang Huajun , Huang Daozheng , Huang Huigen , Zhang Jihui , Guo Lan , Liu Yuting , Ma Huan , Geng Qingshan
Published: July 2020

Background

During previous pandemic outbreaks, medical staff have reported high levels of psychological distress. The aim of the current study was to report a snapshot of the psychological impact of the coronavirus disease 2019 (COVID-19) pandemic and its correlated factors on medical staff in Guangdong, China.

Methods

On the 2nd and 3rd February 2020, soon after the start of the COVID-19 pandemic, we surveyed medical staff at four hospitals in Guangdong, China, to collect demographic characteristics, Hospital Anxiety and Depression Scale (HADS), Perceived Stress Scale (PSS-14), and Insomnia Severity Index (ISI) scores.

Results

Complete responses were received from 1045 medical staff. Respondents were divided into high- and low-risk groups according to their working environment of contacting with potential or confirmed COVID-19 cases. The proportion of staff with anxiety (55.4% v. 43.0%, p < 0.001) or depression (43.6% v. 36.8%, p = 0.028) was significantly higher in the high-risk group than the low-risk group. The percentage of staff with severe anxiety was similar in the two groups. Doctors were more susceptible to moderate-to-severe depressive symptoms. The high-risk group had higher levels of clinical insomnia (13.5% v. 8.5%, p = 0.011) and were more likely to be in the upper quartile for stress symptoms (24.7% v. 19.3%, p = 0.037) than the low-risk group. Additionally, work experience negatively correlated with insomnia symptoms.

Conclusions

It is important for hospitals and authorities to protect both the physical and psychological health of medical staff during times of pandemic, even those with a low exposure risk.
Anomalous origin of right pulmonary artery: diagnosis, treatment, and follow-up in an adult patient
Authors: Pumacayo-Cárdenas Susan , Jimenez-Santos Moises , Quea-Pinto Edgar
Published: July 2020

Anomalous origin of a branch pulmonary artery from the aorta is a rare malformation, accounting for 0.12% of all congenital heart defects. We present the case of a 43-year-old man with an anomalous origin of the right pulmonary artery (AORPA) from the ascending aorta. Reimplantation of the right pulmonary artery was carried out successfully, with favourable evolution in the medium-term follow-up. It is the first described case that receives corrective treatment in adulthood with a favourable evolution.
Brief cognitive behavioural therapy for post-stroke ‘delusional infestation’ in a 71-year-old man: a single case experimental design
Authors: McKinnon Aimee I. , Dow Rebecca
Published: July 2020

Background:

Delusional infestation is a condition at the interface of tactile and visual hallucinations and delusions. Individuals with this condition hold the fixed and false belief that their body or their environment is infested with parasites, insects or other organisms.

Aims:

There are no guidelines or publications detailing the psychological assessment, formulation, intervention and evaluation of this presentation. This paper aims to address this gap.

Method:

Single case experimental design methodology was employed to evaluate the use of cognitive behavioural therapy (CBT) for delusional infestation in a 70-year-old male who was intolerant of anti-psychotic medication. ‘Tom’ had a large, mature infarct in the middle cerebral artery territory as well as a left posterior parietal infarct post-stroke, which may have precipitated his symptoms. After a baseline period of 3 weeks, Tom received eight sessions of CBT based on the model by Collerton and Dudley (2004).

Results:

Post-intervention, there was a reliable improvement on clinical measures as well as a large reduction in distress levels, which was maintained at 3-month follow-up. The conviction in the belief that the infestation was real did not shift.

Conclusion:

This case demonstrated the potential for the use of CBT to address distress related to delusional infestation. This work is discussed in relation to post-stroke psychosis, psychological therapies with older adults, and suggestions are made for future research.
LBNL and the Materials Microcharacterization Collaboratory
Authors: O'Keefe MA , Taylor JR , Owen DK
Published: July 2020

In 1996 the DOE formed the Materials Microcharacterization Collaboratory (MMC) to bring together the four DOE-sponsored electron microscope user facilities in one collaboratory. The MMC will bring the microanalysis and microcharacterization tools that are available in national centers to geographically dispersed researchers working in industries, universities, and Government laboratories. It will enable these remote users to share on-line the instrumentation, knowledge and expertise available at the individual facilities making up the collaboratory.

LBNL first demonstrated on-line remote control of a high-voltage TEM from Kansas City in 1995 in a joint project by LBNL computer scientists and NCEM microscopists. The microscope chosen was a 1.5MeV Kratos EM-1500 that is used for in-situ electron microscopy. In the demonstration, a specimen of an Al/Pb alloy was heated and observed, with remote-operator control of heating rate, microscope focus, and stage movement (translation and tilt).
Integrated Data Acquisition and Instrument Control for Local and Remote Operation of Electron Microscopes Equipped With Imaging Detectors and Spectrometers
Authors: de Ruijter W J , Weiss JK
Published: July 2020

The continuing remarkable progress of computer technology is dramatically changing how electron optical instrumentation is being used. Instead of concentrating on taking just one spectrum or one image at a time, it now has become possible to design complete experiments aimed at solving the problems at hand more rapidly and more directly.

We have designed a PC-based acquisition system that aims to innovate and simplify both TEM and STEM operation. The first advance this system represents is integrated data acquisition from all detectors commonly found on electron microscopes: TV and slow-scan CCD cameras, different flavors of STEM detectors, and EDX, CL, Auger and EELS spectrometers. The new system allows experiments combining microscope control with the acquisition capabilities of all these detectors. The second advance is the implementation of “live” processing. Most common processing tasks can be executed on-the-fly, even at video-rate acquisition speeds.
Image Analysis—Turning Images Into Data
Authors: Friel J J , Prestridge E B
Published: July 2020

Image analysis is the process of quantifying some aspect of an image—its particle size distribution, for example. Manual methods were in use long before computers made image analysis much faster and more reproducible. Linear measurements of diameter, point counting to measure volume fraction, and intercept counting to determine grain size have been used for over 100 years. Automatic image analysis (AIA), however, can make more measurements, and even calculate derived measurements, such as aspect ratio or circularity. AIA of a specimen or micrograph, of course, is only as good as the contrast mechanism used, so the imaging signal must be chosen carefully to reveal to the computer what is to be measured. Obtaining sufficient contrast is often the limiting task.

Once an imaging signal is chosen and the digital resolution set, the computer can analyze the image. The feature descriptors can be generic:
Digital Precision Imaging: Every Pixel Counts
Authors: Peters Klaus-Ruediger
Published: July 2020

Modem technical imaging devices acquire digital image data at a precision level that often exceeds that of available display technologies so that parts of the data information may not be revealed in the displayed image. Data resolution and display resolution are closely related to image information and digital image processing provides several useful tools for compensation of such display deficiencies.

Typical precision data may be captured by a CCD camera, a scanning microscope or flatbed digitizer from photographic film and may exceed a size of 1,000×1,000 data points and a data point depth of 12 bit. Digital data has two general characteristics that deal with spatial resolution and intensity resolution. The distance represented between data points determines the spatial data resolution. Equally important is the bit-resolution which describes the maximum number of intensity levels possible in each point.
A Working Model of a Fully Digital Academic High-Throughput Microscopy Facility
Authors: Dickson M R
Published: July 2020

The Electron Microscope Unit at the University has a good selection of microscopes: two tungsten SEMs, two FESEMs, a microprobe analysis system, a 125 kY TEM, a 200 kV TEM, an AFM, an FIB miller, a Zeiss Photomicroscope and a Leica Macroscope. We service around 300 clients’ projects a year in every field of experimental science and engineering, logging over 8,000 hrs of beam time annually.

But funding constraints have always kept us short staffed and our laboratory has been working towards complete digital image capture for the past ten years to enhance our productivity. The perceived benefits of digitisation for us are:

Photographic processing of negatives eliminated. Archiving of (bulky) photographic negatives eliminated. Need for special darkroom & graphics skills eliminated Responsibility for archiving and indexing images devolved to individual users Responsibility for image processing devolved to individual users. Rapid turnaround of images. Rapid sharing of results.
Local Electrode Atom Probes
Authors: Kelly Thomas F , Camus Patrick P
Published: July 2020

The Need for Improvements. Though atom probe techniques have impressive atomic-scale analytical capabilities, there are some definite needs for improvement. The needle shape of APFIM specimens is a difficult geometry to make for many types of materials, especially technologically important thin-film materials. Even though 3DAPs collect more data than traditional APs, the analysis volumes are still small by analytical standards: typically there are fewer than 1 million atoms in an image which is about 15nm x 15nm x 50nm. The data collection rate (up to tens of atoms per second) limits the practical size of analyzed volumes to about 1 million atoms. Poor mass resolution makes it difficult to separate ions of similar mass-to-charge ratio in spectra of approximately 20% of samples. Thus, there are three principal areas where improvements are desirable: 1) specimen geometry, 2) data collection rates, and 3) mass resolving power.
Microstructural Characterization of Rapidly Solidified Ultrahigh Strength Aluminum Alloys
Authors: Ping D H , Hono K , Inoue A
Published: July 2020

Recently, Inoue et al. succeeded in fabricating ultrahigh-strength Al-based alloys consisting of a nanoscale mixture of α-Al and amorphous phases or a mixture of a-Al, amorphous and icosahedral phases in Al-TM-Ce, Al-TM-Ln (TM: transition metals) and Al-Cr-Co-Ce systems by rapid solidification [1-3]. In order to understand the mechanism of the nanoscale microstructural evolution during the rapid solidification processes in these nanocomposite alloys, we have characterized the microstructures of rapidly solidified Al94.5Cr3Co1.5Ce1 and Al96V4Fe2 alloys by atom probe field ion microscopy (APFIM) and high resolution transmission electron microscopy (HREM).

TEM investigations have revealed that the as-quenched Al94.5Cr3Co1.5Ce1 alloy is composed of a nanoscale mixture of amorphous and α-Al. A typical TEM bright field micrograph is shown in Fig. 1. The microdiffraction patterns taken at various locations in the darkly contrasted region have shown that the region consists of a few interconnected α-Al grains and many localized amorphous regions which are trapped within the Al grains.
Compositional Imaging At The Sub- 2 Å Level Using A 200 Kv Schottky Field Emission Transmission Electron Microscope
Authors: James E M , Browning N D , Nicholls A W , Kawasaki M , Stemmer S , Xin Y , Duscher G
Published: July 2020

Here we demonstrate sub- 2Å resolution, in compositionally sensitive Z-contrast imaging, for a 200 kV field-emission transmission electron microscope (FEGTEM). This method has shown great promise for determining the atomic structure of interfaces in such materials as ceramics, semiconductors and high-Tc superconductors.

The Z-contrast technique involves focusing an electron probe at a specimen surface (which is oriented with a zone-axis along the beam direction). The transmitted signal, at an annular detector, is displayed on a VDU, rastered synchronously with the probe. Coherent, contrast reversal effects are suppressed in this geometry; images approximate to a convolution of the probe intensity profile with the square of the projected specimen potential. The Z2 dependence means that images can, with care, be interpreted as chemically sensitive maps of the projected structure. Furthermore, electron energy loss spectroscopy (EELS) can be performed simultaneously with Z-contrast imaging to yield additional compositional information.
Quantitative Compositional Mapping of Phase Separation in Thin Polymer Films
Authors: Winesett DA , Ade H , Smith AP , Qu S , Ge S , Rafailovich M , Sokolov S
Published: July 2020

Experiments and theoretical work on spinodal decomposition of thin films of binary polymer blends indicate large changes in phase behavior and dynamics relative to the bulk behavior due to the complex interactions of the polymer-polymer, polymer-air, and polymer-substrate interfaces. Currently used techniques are able to sense growing domain sizes but are not always able to sense local two and three dimensional variations within domains. We are using a new characterization approach to these thin films utilizing the Scanning Transmission X-ray Microscope (STXM) at beamline XIA at the National Synchrotron Light Source (NSLS)2. We extract component thickness maps of each polymer in a sample region. This allows for quantitative investigation of the dynamics of polymer phase separation and should allow the determination of important parameters affecting the domain formation in these thin films.
Compositional Characterization of an O-N-O Layer in a Dram Using FE-TEM and Energy Filtered Elemental Mapping
Authors: Kawasaki M , Oikawa T , Ibe K , Park K H , Shiojiri M , Kersker M
Published: July 2020

A dielectric O-N-O multi-layer is formed between a single-crystal silicon substrate and a polycrystalline silicon gate to insulate them. The nominal structure of the layer is SiO2-Si3N4-SiO2. In this study, in order to visualize the elemental distribution, energy filtered mapping technique was used and also the relative concentration was calculated from the intensities of the elemental maps to characterize the structure quantitatively.

The specimen was cut from a 16M-DRAM device and made suitable for TEM observation by the cross-section ion milling method. The O-N-O layer was examined using a JEM-2010F FE-TEM equipped with a post column energy filter(GIF 200). Fig. 1 shows energy filtered elemental maps of Si, O and N with an elastic image of the O-N-O layer obtained by the three-window method.

As a map is produced after a background intensity extrapolated from two pre-edge images is subtracted from a post-edge image, each pixel of these maps provides energy loss intensity of an element.
The Impact of Biological Microanalysis on Analytical Electron Microscopy
Authors: Somlyo Andrew P
Published: July 2020

Advances in energy-dispersive detector technology were largely responsible for electron probe microanalysis (EPMA) becoming a valuable tool for biologists, while development of EPMA received much impetus from the special needs of biological research. Solid-state energy-dispersive detectors placed in close proximity to specimens in transmission electron microscopes (TEMs) provided the necessary geometric detection efficiency, hence sensitivity and higher spatial resolution, and the reasonably good energy resolution of these detectors permitted reliable separation of overlapping peaks, such as the Kα peak of the biologically important messenger, calcium, and the Kβ peak of another, biologically much more abundant element, potassium. Improvements in the pole-piece design of TEMs to allow closer access of the X-ray detector to the specimen and interfacing the software of one company with detectors provided by another also helped progress, and EPMA, in conjunction with rapid freezing of cells, was ready to address important biological problems, such as the dynamics of the composition of intracellular organelles in situ.
Superconducting Tunnel Junction Spectrometers for High Resolution Energy Dispersive Spectroscopy
Authors: Mears Carl A
Published: July 2020

We have been developing superconducting tunnel junctions (STJs) for use as high-resolution energy dispersive spectrometers. STJ detectors simultaneously offer energy resolution better than 15 eV at 1 keV, count rates in excess of 10,000 counts per second, broad bandwidth and high efficiency. These attributes make them desirable detectors in a variety of applications, including x-ray microanalysis.

When an x-ray photon is absorbed in a superconductor, about 60% of its energy is used to break the Cooper pairs that make up the superconducting ground state into excited electron-like and hole-like states called quasiparticles. This process is analogous to the creation of electron-hole pairs in a conventional energy dispersive spectrometer (EDS) based on silicon or germanium. The difference is that the superconducting energy gap Δ is on the order of a few millielectron volts, roughly a factor of 1000 less than the band gap in common semiconductors.
X-Ray Emission from Porous Materials : New Results
Authors: Gauvin Raynald
Published: July 2020

This paper present new results about x-ray emission from porous materials obtained from Monte Carlo simulations. This is an update from the results which have been presented for the first time last year. In particular, the absorption correction is now simulated in the same way as the electron scattering. In the results presented last year, x-ray absorption was calculated with the integration of the φ(ρz) curves via the usual equation :

where I is the intensity emitted from the porous specimen, I0 is the intensity emitted from a thin foil with no porosity, x is the mass absorption coefficient times the cosine of the take off angle, z is the depth in the specimen and ρ is the density of the porous materials. Since the density term does not include the effect of the size of the pores, integration of this equation will give wrong results when the size of the pores are big relative to the electron range.
Quality Assurance of Energy Dispersive Spectrometry Systems
Authors: Steel E B , Marinenko R B
Published: July 2020

Monitoring the performance and capabilities of energy dispersive X-ray spectrometers (EDS) and related x-ray analysis electronics and software is important for maintaining and improving the reliability, sensitivity, and accuracy of the x-ray analysis system. There is growing demand for quality systems through laboratory accreditation, ISO 9000, ISO Guide 25 and related programs that require set quality control procedures for analytical instrumentation. In such cases it is frequently more useful to have one national/international standard. This approach is not only more efficient than having each analyst devise their own system, but the use of the same standard procedures among labs would allow direct intercomparison of results. This intercomparison can help labs and manufacturers determine what are normal versus abnormal results and lead to higher quality instruments and analyses.

We are designing a standard procedure to maximize the efficiency of each quality control (QC) measurement so that we spend as little time monitoring the analysis system as is possible.
Extracting Low Energy X-Ray Peaks From EDS and WDS Spectra
Authors: Myklebust Robert L , Newbury Dale E
Published: July 2020

Interest in electron beam x-ray microanalysis with low incident beam energies, defined arbitrarily as 5 keV and below, has been greatly stimulated in recent years by the development of the high performance field emission gun scanning electron microscope (FEG-SEM), which can produce a nanometer-scale probe with sufficient current to operate with both energy dispersive (EDS) and wavelength dispersive (WDS) spectrometers. Microanalysis in this regime requires the analyst to confront new spectrometry problems that are not typically encountered, or that can be safely ignored, when operating with conventional beam energies, 10 keV or greater. With low energy operation, the choice of atomic shells that can be accessed is restricted, forcing the analyst to make use of shells that have low fluorescence yields for intermediate and high atomic number elements, and possibly strong chemical effects, which are evident with high resolution x-ray spectrometry.
Using Quantitative Iteration to Correct for Pathological Spectral Interferences
Authors: Donovan John J
Published: July 2020

A number of problematic analytical situations are known to exist in electron probe microanalysis (EPMA) where characteristic x-ray spectral overlaps are not only severe, but are also of the “self-interfering” or “cascade” variety. The “self-interfering” variety is exemplified by the innocuous Ba Lα ↔ Ti Kα; to the fearsome Pb Lα↔As Kα binaries, while “cascade” interferences are often seen among the transition metal series as in Ti Kβ → V Kα - V Kα Cr Kα or as seen with a secondary fluorescence interference effect as in Ni K ⇒ Fe Kα - Fe Kβ → Co Kα. Unlike simple interferences of the type Mn Kβ → Fe Kα, both of these types of spectral interferences are often quite troublesome for the analyst to correct for, especially for Si(Li) and Ge energy dispersive spectrometers (EDS) where the analytical peaks are often so overlapped as to prevent graphical deconvolution, and even for the higher resolution wavelength dispersive spectrometers (WDS) along with the yet to come bolometric energy dispersive detectors (based on projected resolution), the task can still be formidable.
The Role of Monte Carlo Calculations In Quantitative Analysis
Authors: Lifshin E , Peluso L A , Gauvin R
Published: July 2020

In conventional quantitative electron microprobe analysis, methods like ZAF and φ(ρz), are used to convert x-ray intensity data to chemical composition utilizing equations that describe electron solid interactions, the x-ray generation process, absorption of the generated x-rays and secondary fluorescence effects. These equations capture the overall response of a sample or standard rather than consider the fate of individual electrons over time. For example, f(χ) is simply the ratio of x-rays emitted to the number generated. While for the most part these methods are built on solid physical models, the models were never exact enough to completely match measured data. Consequently, they have been modified by various adjustable parameters to ensure a high level of accuracy for a wide variety of systems and experimental conditions. However, since most of the adjustments were based on data taken at normal incidence, there has always been a question of how to obtain accurate results from tilted samples.
Characterization of Archaeological Ceramics Using Scanning Electron Microscopy and Electron Microprobe Analysis
Authors: Spilde MN , Olsen NH , Creager N
Published: July 2020

We have used several techniques in the field of scanning electron microscopy (SEM) to examine ceramic pot sherds from a number of archaeological sites in New Mexico in an effort to characterize the ceramic material and determine the origin of some of the vessels. Typical archaeological sites belonging to Pueblo Indian ancestors in New Mexico are littered with numerous fragments of vessels which served different purposes such as cooking, food/water storage, eating, and ceremonial. often different styles of painting and slipping found on these fragments relate to different temporal and cultural influences. An important question that arises during examination of the many types of sherds involves the origin of each of the vessels. Analysis of mineral content and mineral chemistry can help answer these questions.

Thin sections of pot sherds from 4 prehistoric Anasazi sites (A.D. 1150-1250) from south and central New Mexico, a prehistoric Anasazi site in northwestern New Mexico (Chaco Canyon, Pueblo Alto A.D. 1000 -1150), and an historic Pueblo site from the Spanish period (A.D. 1540-1700) were examined.
Quantitative Elemental Analysis of the Components of Pb Exposed Cells Of Plectonema Boryanum Using Regular and Overplus Cells: an Energy Disspersive X-Ray Spectroscopy Study
Authors: Goldberg JJ , Jensen TE
Published: July 2020

The elemental composition of polyphosphate bodies (PPB’s) and other components of the cell have previously been determined by using energy dispersive X-ray spectrometers(EDX). In this present study we perform a quantitative analysis or normally grown cells and cells that were grown in the overplus phenomenon.

Cells of Plectonema boryanum were grown in modified Fitzgerald's media and harvested after a logarithmic growth phase of 14 days. The overplus cells were grown as has been previously described2. The cells were exposed to l00ppm of lead, as well as other metals separately, for one hour. The cells were then fixed and embedded in EPON according to Luft's procedure.

For X-ray analysis cells were first located using the TEM mode, and then the microscope was switched to the STEM mode. Analysis of cell components were carried out using the spot mode (75Kv).
Montages Link Microscopic to Macroscopic Information in Concrete Analys
Authors: Doerr A , Badger S , Brown P , Sahu S
Published: July 2020

One of the limitations of microscopy is that only a relatively small area is viewed and that both microscopic and macroscopic information is needed to better understand a process or relationship. Microscopic structures that can only be seen at high magnification may appear insignificant at magnifications required to see macroscopic structures. Montages from the scanning electron microscope (SEM) and optical microscope allow large areas to be displayed at relatively high magnifications revealing both macroscopic and microscopic features.

The use of automated digital microscopy and image software have reduced the barriers for creation of montages and provided new display modes, thereby stimulating their use as an enhanced data acquisition, review, and interpretation technique.

The ability to create digital montages is a valuable tool in the analysis of cement and concrete. It has been used to evaluate the relationship between small scale deleterious phases and their larger scale effects.
Electrons, Ions and Cathodoluminescence in the Environmental SEM
Authors: Griffin Brendan J
Published: July 2020

“Secondary” or ‘low energy’ electron emission in the environmental SEM is a complex summation of surface and near surface interactions of electron and ions, fields developed within the sample and conventional electron-sample interactions. Little is understood about the first two aspects and recent data has illustrated limitations on our understanding of cathodoluminescence. The recently described Charge Contrast Imaging (CCI) has drawn attention to the fact that the role of ions in the environmental SEM have been largely ignored. Generally the positive ions have been regarded to provide charge cancellation at the specimen surface but otherwise to have little effect. This view has persisted in the face of evidence that even without gas amplification effects, charge neutral conditions are obtained at the sample surface with a chamber gas pressure of 0.1 torr2, a pressure far lower than normal operating conditions for the ESEM (1 -2 0 torr).
An In Situ Scanning Tunnelling Microscopy Study of the Adsorption of the Aurocyanide Ion Onto Highly Orientated Pyrolytic Graphite
Authors: Poinen GE , Thurgate SM
Published: July 2020

Gold is an important mineral whether for its value, properties or its natural beauty. It is expected that in a few years Australia will be the second largest producer of gold. Present gold mining practices, though able to recover minute amounts of gold, can be improved. In the current process, gold is dissolved in an alkaline cyanide solution to form Au(CN)2, which is adsorbed onto activated carbon. Activated carbon has shown a special affinity for the gold complex even in the presence of other metalcyanide complexes at much greater concentrations in the pulp. This process is efficient and is able to recover gold at a concentration of 1 part per million in the auriferous ore. The adoption of the carbon technology has contributed substantially to the increased output of Australian gold. Within 15 years, local production has increased more than ten-fold over.
The SPM Study of Surface Healing Due to Mass Transport in the Liquidlike Layer of Ice
Authors: Trickett D M , Petrenko V F
Published: July 2020

This work employed scanning probe microscopy (SPM) to study mass transport in the liquid-like layer (LLL) ice surfaces. Rapid healing of the damaged ice surface that took place only in the presence of the LLL was recently observed. This indicates that the LLL is responsible for the surface healing. Simple modeling shows that the healing rate is proportional to the LLL thickness cubed and inversely proportional to the film's viscosity. Thus an experimental study of the healing can provide valuable information on the physical parameters of the LLL.

Pure distilled deionized water, with a specific resistivity of 18.1 MΩ•cm, was used to grow ice crystals. The crystal surface was then prepared for scanning force microscopy (SFM) by either flattening using a microtome machine or flattening with the microtome machine and polishing gently using optically smooth clean quartz plates.
Computer Analysis of Electron Diffraction From thin Films
Authors: MoberlyChan Warren , Kilaas R , Chan L-H , Nolan T , Dorsey P , Cao W , Lu M , Gopal M , Yamashita T
Published: July 2020

As engineering properties are miniaturized by mo thinner films, crystallographic analyses become more appropriate by electron diffraction than XRD. Without synchrotron sources, XRD scans of such films often expose one peak at best. However, these thinner films become more suited for TEM, with less artifacts from sample preparation. XRD scans with peaks in the noise are quantitatively accepted, while vast differences in electron diffraction patterns remain unquantified. Digital recording of TEM information removes the uncertain hand waving of the darkroom; and fast, user-friendly computer processing especially removes the nonstatistical art in image analysis. This work inputs 16-bit (>65,000 gray levels) images of ring diffraction patterns into Digital Micrograph and utilizes a Rotation Average subroutine (1) to plot peak intensities.

Information storage in a hard drive utilizes sputtered thin films of HCP-Co-alloys with magnetic bits tied to the crystallographic orientation of each grain. Longitudinal-recording density and signal-to-noise can be enhanced for thin films with c-axes of all grains in plane.
Spatially-Resolved X-Ray Absorption fine Structure (XAFS) Spectroscopy Using Undulator Radiation Focused by Dynamically-Bent Elliptical Mirrors
Authors: Sutton S R , Eng P E , Rivers M L , Newville M
Published: July 2020

X-ray absorption spectroscopy (XANES and EXAFS) applied with x-ray microprobe instrumentation (figures 1) can be used for studying the electronic structure of specific elements in complex materials in a spatially-resolved manner (figure 2). Such techniques are valuable in a wide range of studies including hydrothermal fluid processes, migration and encapsulation of toxic and radioactive wastes, and redox evolution of solar system bodies.

One of the major technical challenges in this work is the production of high flux microbeams from high power, hard x-ray synchrotron sources. Some of the microbeam technologies under development include tapered glass capillaries, zone plates, and elliptical mirrors. Each approach has advantages and disadvantages and the optimum microfocusing device depends on the particular experiment.

One of the most versatile of these devices is the dynamically bent, elliptical mirror, especially when a pair of mirrors are arranged in a Kirkpatrick-Baez (KB) geometry to provide two-dimensional focusing. This versatility derives mainly from four attributes.
On the Effects of Spherical Aberration and Aperture Misalignment on the Formation of Small Electron Probes
Authors: Garratt-Reed Anthony J , Cliff Graham , Kenway Peter B
Published: July 2020

A major reason for performing microanalysis in the Field-Emission Gun Scanning Transmission Electron Microscope (FEG-STEM) is the very high spatial resolution of the information obtained. It has been estimated that in ideal cases, energy-dispersive x-ray analysis in such an instrument can provide 0.1 wt.% detection sensitivity for an element in a region about 1.5nm in diameter of a foil about 30nm thick. It is obvious that such performance requires that the instrument be properly adjusted, and hence that the probe-forming characteristics be fully understood.

There are three fundamental limits on the minimum size of an electron probe, these being i) the geometrical demagnification of the source, ii) diffraction at the beam-limiting aperture, and iii) spherical aberration in the probe-forming lens. In addition, misalignment of the beam-limiting aperture will result in probe aberrations.
Development of a Philips cryo-TEM provided with a liquid helium cooled tilt stage and a vacuum transfer system
Authors: Wagner R , de Jong AF , Koster AG , Morrison R , Tothill F , Lücken U
Published: July 2020

In order to reduce beam damage, biological TEM specimens are often observed at temperatures close to the boiling point of liquid nitrogen (77 K). Recently, encouraging results on single particles as well as on 2D crystals have appeared, derived from images taken near liquid helium temperature (4 K), in dedicated TEMs. At these temperatures the high resolution frequencies are much better preserved, increasing the allowable dose and thus the signal to noise ratio.4 Here we present the design of a new dedicated Philips He-TEM which combines the full functionality of a CM300 TWIN with a vacuum transfer system and a liquid helium cooled specimen holder.

A schematic overview of the Cryo-TEM is shown in figure 1. The key differences compared to a standard CM microscope are: 1) The tip of the specimen rod is cooled below 10 K and the rod itself cannot be taken out of the goniometer (CompuStage). 2) The specimen enters the column on the opposite side.
Second Harmonic Generation Imaging (SHG) in the Non-Linear Optical Microscopy of Living Cells
Authors: Campagnola PJ , Loew LM
Published: July 2020

In recent years there has been considerable interest in two and three-photon excited fluorescence in laser scanning optical microscopy. Because absorption is confined tot he focal plane of the objective, these techniques provide intrinsic optical sectioning without the use of a confocal aperture. In addition, photobleaching and phototoxicity are greatly reduced above and below the focal plane. We have adapted a two-photon microscope to utilize surface second harmonic generation (SHG) as a new contrast mechanism for nonlinear optical biological imaging.

Surface SHG was first described by Shen [1] and arises from the second order nonlinear susceptibility, χ(2). Signal will only arise from a non-centrosymmetric environment such as an interfacial region. Thus this technique has the potential to probe cellular membranes at high specificity. Further, since SHG results from an induced polarization and not absorption, photobleaching considerations are greatly reduced over fluorescence based methods.
In-Depth Imaging Using Two-Photon Excitation Microscopy
Authors: Gerritsen HC , Vroom JM , de Grauw CJ
Published: July 2020

Two-Photon Excitation (TPE) microscopy is a powerful tool for the imaging of biological specimen. The most important advantages compared with conventional confocal microscopy are: intrinsic optical sectioning, reduced phototoxcicity and photobleaching, and an increased penetration into the specimen. The increased penetration arises from the use of the longer wavelength excitation light, in the red or near infra-red.

Here, a quantitative in-depth TPE imaging study is presented on dental biofilm. The biofilm contains a mixed culture of a large number of oral bacteria with a typical size of ≈ 1 μm diameter. They exhibit a complex microstructure and heterogeneous physiological and biochemical properties. The high density of the biofilms limits the depth range over which confocal images can be acquired to 25-40 μm.

Using a two-photon excitation microscope fluorescence intensity images could be recorded over the whole thickness (100 μm) of the biofilm sample.
Confocal Imaging of Both Mitochondrial and Cytosolic Free Ca2+ in Cardiac Myocytes Co-Loaded with Rhod 2 and Fluo 3: Inhibition by Ruthenium Red of Mitochondrial but not Cytosolic Ca2+ Transients
Authors: Trollinger Donna R , Cascio Wayne E , Lemasters John J
Published: July 2020

Previously, we showed rapid mitochondrial Ca2+ transients in adult rabbit cardiac myocytes during the contractile cycle. Ruthenium red, an inhibitor of mitochondrial Ca2+ uptake by the Ca2+ uniporter, inhibits mitochondrial Ca2+ transients in adult rabbit cardiac myocytes during electrical stimulation. Here, we extend this finding to show that ruthenium red inhibition is specific for mitochondrial Ca2+ transients and not cytosolic Ca2+ transients.

Ca 2+-tolerant adult rabbit cardiac myocytes were isolated by collagenase and hyaluronidase digestion and loaded in the cold with 2.5 μM Rhod 2-AM for 30 minutes. Subsequently, the cells were incubated in nutrient medium at 37°C for 4-6 hours during which time cytosolic but not mitochondrial Rhod 2 was lost. Subsequently, the myocytes were loaded with 10 μM Fluo 3-AM for 15 minutes at 37°C, conditions that lead to predominantly cytosolic localization of Fluo 3. In sequential scans, the red fluorescence of Rhod 2 and the green fluorescence of Fluo 3 were imaged using a Zeiss LSM 410 laser scanning confocal microscope.
Actin Filaments Decorated with Cytoskeletal Proteins
Authors: Hanein D , Goldsmith S , Lehman W , Craig R , Correia I , Matsudaira P , DeRosier DJ , Almo SC
Published: July 2020

A superfamily of actin crosslinking proteins, the calponin-homology domain (CH) family is implicated in directing the assembly and controlling the organization of the cytoskeleton through a highly conserved actin binding domain (ABD). This domain, composed of a tandem pair of CH motifs, is found in actin crosslinking proteins such as fimbrin, alpha-actinin, spectrin, and dystrophin. In addition to its role in crosslinking actin filaments, a putative homologous ABD in intermediate filament-binding proteins, plectin, dystonin, and BPAGlnl, suggests a possible role in crosslinks between desmosomal and vimentin intermediate filaments and actin. Thus, the CH domain could integrate the functions of the actin and IF cytoskeletons by physically linking these structural systems. We present an atomic model for the complex of the CH domain and actin.

In crosslinking proteins that organize actin into two and three dimensional networks or gels the ABDs lie at the ends of long, flexible molecules.
The UCF/CIRENT Materials Characterization Facility
Authors: Giannuzzi LA , Bindell JB
Published: July 2020

New state-of-the-art analytical equipment is becoming more specialized and more expensive. With the availability of federal funding decreasing over the years, it has become increasingly difficult for University laboratories to maintain and upgrade existing analytical equipment, or purchase new analytical equipment. There are also instances where large industrial laboratories may only need a particular piece of analytical equipment on a part-time basis, or where small companies cannot afford to purchase a particular technique. An obvious solution to these problems is to merge industry and university into a viable working collaboration whereby resources are shared among partners.

The University of Central Florida and Cirent Semiconductor (a joint venture of Lucent Technologies and Cirrus Logic) have entered into such a collaboration with the development of the UCF/Cirent Materials Characterization facility (MCF). The MCF is a shared user facility that is available to (i) UCF and other State University System (SUS) Florida University students, faculty, and staff, and (ii) MCF industrial affiliates and others requiring specialized instrumentation and expertise.
Scanning Electron Microscopy/Energy Dispersive X-Ray Spectrometry (SEM/EDS): The Last Step in the Microanalysis of Particulate Matter Isolates
Authors: Maxwell RJ , Smith MA , Aldrich DS
Published: July 2020

The SEM/EDS is a valuable tool in the pharmaceutical industry for aiding in the identification of isolated particles. It is a part of our systematic approach which proceeds from lower magnification techniques, e.g., stereomicroscope, to higher magnification techniques, eg., polarized light microscopy, and finally to the high magnification of SEM/EDS. Particles associated with pharmaceutical product rejects are due to a variety of sources, often due to the ubiquitous use of some materials, e.g., stainless steel alloys, in the manufacturing arena. Our particles of interest range in size from submicron to ≥ 50 μm (visible with the unaided eye), appearing in numerous shapes and/or colors. Any particles contained in a drug product or associated with the package are objectionable. Detection during production operations and/or during the terminal 100% inspection prior to market release will cause product rejection. In any case, foreign particles are not tolerated. Their identification leads to their source and thus proper corrective action.
Characterization o Solid-State Vortices Associated with the Friction-Stir Welding of Copper to Aluminum
Authors: Flores R D , Murr L E , Trillo E A
Published: July 2020

Although friction-stir welding has been developing as a viable industrial joining process over the past decade, only little attention has been given to the elucidation of associated microstructures. We have recently produced welds of copper to 6061 aluminum alloy using the technique illustrated in Fig. 1. In this process, a steel tool rod (0.6 cm diameter) or head-pin (HP) traverses the seam of 0.64 cm thick plates of copper butted against 6061-T6 aluminum at a rate (T in Fig. 1) of 1 mm/s; and rotating at a speed (R in Fig. 1) of 650 rpm (Fig. 1). A rather remarkable welding of these two materials results at temperatures measured to be around 400°C for 6061-T6 aluminum welded to itself. Consequently, the metals are stirred into one another by extreme plastic deformation which universally seems to involve dynamic recrystallization in the actual weld zone. There is no melting.