bluuebunny/crossref_metadata_2025 huggingface dataset:
Difficulties when using video playback to investigate social cognition in California scrub-jays (Aphelocoma californica)
Authors: Brecht Katharina F. , Ostojić Ljerka , Legg Edward W. , Clayton Nicola S.
Published: March 2018

Previous research has suggested that videos can be used to experimentally manipulate social stimuli. In the present study, we used the California scrub-jays’ cache protection strategies to assess whether video playback can be used to simulate conspecifics in a social context. In both the lab and the field, scrub-jays are known to exhibit a range of behaviours to protect their caches from potential pilferage by a conspecific, for example by hiding food in locations out of the observer’s view or by re-caching previously made caches once the observer has left. Here, we presented scrub-jays with videos of a conspecific observer as well as two non-social conditions during a caching period and assessed whether they would cache out of the observer’s “view” (Experiment 1) or would re-cache their caches once the observer was no longer present (Experiment 2). In contrast to previous studies using live observers, the scrub-jays’ caching and re-caching behaviour was not influenced by whether the observer was present or absent. These findings suggest that there might be limitations in using video playback of social agents to mimic real-life situations when investigating corvid decision making.
‘What Was I Thinking?!’ Rhetorical Questions as a Technique to Identify and Explore Impasses in Therapy
Authors: García Pérez de León Carmen
Published: March 2018

Rhetorical questions emerging spontaneously in consultations can be used as a tool for developing self‐reflexivity and exploring the therapeutic alliance in the process of therapy with couples and families. This paper presents a technique based on the enunciation of rhetorical questions, which can point to an impasse in the process of therapy and contain a key to its resolution. The technique focuses on the distinctive feature of rhetorical questions as convening a paradoxical injunction: a question not intended as a question, while uttered as such. The technique in four steps is illustrated by examples from therapy, supervision, consultation, and self‐supervision. Its focus is the interlink between the therapeutic relationship and the process of therapy and it is informed by a second‐order cybernetics approach, dialogical practice, and the systemic literature on emotion. The technique can help develop curiosity in working with families, lead to unforeseen developments, and touch on prejudices not made explicit in previous therapeutic encounters. Whether we are acting as supervisors, therapists, or clients, the creation of a ‘secure enough’ context for rhetorical questions becomes critical to allow freeform exploration.
My “Inside‐the‐Beltway” Crystal Ball Is Broken
Authors: Roberson J. Alan
Published: March 2018

The current political situation in the united states makes predicting the regulatory future a challenge, but there are three main areas facing the water sector: uncertainties, funding and staffing needs, and nonregulatory drivers.
Information Needs for Water Demand Planning and Management
Authors: Kiefer Jack C. , Krentz Lisa R.
Published: March 2018

A collaborative study that focused primarily on water utilities was conducted to determine barriers—and solutions—to effectively collecting, analyzing, and applying water use data.
Top-philic Z′ forces at the LHC
Authors: Fox Patrick J. , Low Ian , Zhang Yue
Published: March 2018

Abstract

Despite extensive searches for an additional neutral massive gauge boson at the LHC, a Z

′
at the weak scale could still be present if its couplings to the first two generations of quarks are suppressed, in which case the production in hadron colliders relies on tree-level processes in association with heavy flavors or one-loop processes in association with a jet. We consider the low-energy effective theory of a top-philic Z

′
and present possible UV completions. We clarify theoretical subtleties in evaluating the production of a top-philic Z

′
at the LHC and examine carefully the treatment of ananomalous Z

′
current in the low-energy effective theory. Recipes for properly computing the production rate in the Z

′
+ j channel are given. We discuss constraints from colliders and low-energy probes of new physics. As an application, we apply these considerations to models that use a weak-scale Z

′
to explain possible violations of lepton universality in B meson decays, and show that the future running of a high luminosity LHC can potentially cover much of the remaining parameter space favored by this particular interpretation of the B physics anomaly.
Comparison of Scrub Typhus Meningitis with Acute Bacterial Meningitis and Tuberculous Meningitis
Authors: Kakarlapudi Svas Raju , Chacko Anila , Samuel Prasanna , Verghese Valsan Philip , Rose Winsley
Published: March 2018

Objective

To compare scrub typhus meningitis with bacterial and tuberculous meningitis.

Methods

Children aged<15 years admitted with meningitis were screened and those who fit criteria for diagnosis of scrub typhus meningitis (n=48), bacterial meningitis (n=44) and tuberculous meningitis (n=31) were included for analysis. Clinical features, investigations and outcomes were compared between the three types of meningitis.

Results

Mean age, duration of fever at presentation, presence of headache and, altered sensorium and presence of hepatomegaly/splenomegaly were statistically significantly different between the groups. Scrub typhus had statistically significant thrombocytopenia, shorter hospital stay and a better neurological and mortality outcome.

Conclusions

Sub-acute presentation of meningitis in older age group children, and good outcome is associated with scrub typhus when compared to bacterial and tuberculous meningitis.
Creatine Transporter Deficiency in Two Brothers with Autism Spectrum Disorder
Authors: Aydin Halil Ibrahim
Published: March 2018

Background

Creatine transporter deficiency (CTD) is a treatable, X-linked, inborn error of metabolism.

Case characteristics

Two brothers with autism spectrum disorder were diagnosed with CTD at the ages of 17 and 12 years. Both were found to have a previously reported hemizygous p.408delF (c.1216_1218delTTC) deletion mutation.

Outcome

Both patients were given creatine monohydrate, L-arginine, L-glycine and S-adenosylmethionine, which partially improved the behavioral problems.

Message

Serum creatinine levels, creatine peak at brain MR spectroscopy or creatine/creatinine ratio in urine should be evaluated to identify CTD in children with autistic behavior and language disorders.
Time evolution of uniform momentum zones in a turbulent boundary layer
Authors: Laskari A. , de Kat R. , Hearst R. J. , Ganapathisubramani B.
Published: March 2018

Time-resolved planar particle image velocimetry was used to analyse the structuring of a turbulent boundary layer into uniform momentum zones (UMZs). The instantaneous peak-detection method employed by Adrian et al. (J. Fluid Mech., vol. 422, 2000, pp. 1–54) and de Silva et al. (J. Fluid Mech., vol. 786, 2016, pp. 309–331) is extended to account for temporal coherence of UMZs. The resulting number of zones detected appears to follow a normal distribution at any given instant. However, the extreme cases in which the number of zones is either very high or very low, are shown to be linked with two distinct flow states. A higher than average number of zones is associated with a large-scale $Q2$ event in the log region which creates increased small-scale activity within that region. Conversely, a low number of zones corresponds to a large-scale $Q4$ event in the log region and decreased turbulent activity away from the wall. The residence times, within the measurement plane, of zones belonging to the latter scenario are shown to be on average four times larger than those of zones present during higher than average zone structuring states. For both cases, greater residence times are observed for zones of higher momentum that are generally closer to the free stream.
Is the Good News About Law Compliance Good News About Norm Compliance? The Case of Racial Equality
Authors: Búzás Zoltán I.
Published: March 2018

The most important international human rights norms are legalized or codified in international treaty law. Yet pernicious practices at odds with these norms endure and sometimes even increase after legalization. According to conventional wisdom, this is because agents commit to but do not comply with international law and the underlying norms. I develop a theory of evasion to explain why norm violations persist even when states technically comply with the law. Because legalization transposes social norms into international law imperfectly, it creates gaps between laws and underlying norms. Because of these norm-law gaps, legality and normative appropriateness will diverge. States caught between opposing pressures from pro-violation and pro-compliance groups exploit this gap through what I call evasion—the intentional minimization of normative obligations that technically complies with international law but violates underlying norms. I demonstrate the theory's empirical purchase in the cases of the French expulsion of Roma immigrants and the Czech school segregation of Roma children. Under the cover of technical compliance with the law, these states violated the norm of racial equality. The argument cautions that the good news about law compliance is not necessarily good news about norm compliance, broadens our understanding of norm violators' agency, and has practical implications for human rights advocacy.
Colonisation of stranded whale bones by lichens and mosses at Hennequin Point, King George Island, Antarctica
Authors: de Albuquerque Margéli Pereira , Putzke Jair , Schünemann Adriano Luis , Vieira Frederico Costa Beber , Victoria Filipe de Carvalho , Pereira Antonio Batista
Published: March 2018

This paper presents the details of lichens and mosses found on whale vertebrae substratum in the Admiralty Bay area, King George Island, Antarctica. Samples were taken in the coastal area at Hennequin Point, a relict of the Antarctic whaling era. The samples were collected from the upper surface of the whale bones found in the study area during the austral summer 2010–2011. A total of 15 lichen and two moss species were found. All species sampled are known in the Admiralty Bay area, both as pioneers and in more advanced succession stages in ice-free areas. These results suggest that the colonisation of whale bones is not new for Antarctic plants, but it is an additional substrate on which these plants can develop. A map showing the distribution of colonised bones and details of the usual substrata for the lichens and mosses found in this study are provided.
Progress of negative symptoms over the initial 5 years of a first episode of psychosis
Authors: Lutgens Danyael , Joober Ridha , Iyer Srividya , Lepage Martin , Norman Ross , Schmitz Norbert , Mustafa Sally , Abadi Sherezad , Malla Ashok
Published: March 2018

Background

Specialized early intervention (EI) following a first episode of psychosis (FEP) are effective at reducing negative symptoms, although its trajectory warrants systematic assessment. However, findings are equivocal as to whether extended gains are made post 2 years of EI and whether there is additional benefit of extending EI for an additional 3 years.

Methods

Data on 178 FEP patients, from a randomized controlled trial of a 3-year extension of EI service v. transfer to regular care following 2 years of EI service, were used for this report. Repeated measures analysis of variance were conducted separately for the initial 2 years of treatment in an EI service, and for the 3-year post-randomization to examine trajectories of negative symptoms over the two periods in the two arms of the study.

Results

There were significant improvements in total negative symptoms over the first 2 years of EI F(4.612, 797.905) = 25.263, p < 0.001 and in domains of ‘expressivity’ and ‘motivation’. In the following 3 years, there were further significant improvements in negative symptoms F(4.318, 759.908) = 4.182, p = 0.002 with no difference between groups F(4.318, 759.908) = 1.073, p = 0.371. Changes in negative symptoms over the extension period were driven by expressivity F(4.01, 674.73) = 7.19, p < 0.01, but not motivation F(6.58, 1112.18) = 0.95, p = 0.46.

Conclusion

Negative symptoms improve significantly over the first 2 years of EI. Subsequent amelioration was largely the result of expressivity. Motivation deficits remained stable. Extended EI offered no advantage over regular care post-randomization.
The Rotation of the Main-Sequence Components of Algol-Type Semi-Detached Eclipsing Binaries
Authors: Heuvel E.P.J. Van Den
Published: March 2018

Newly determined rotational velocities of the main-sequence components of 14 Algol-type semi-detached systems and of 2 detached systems are presented. Combination of these data with the existing data on the rotation of the components of semi-detached systems shows that (i) in systems with primaries of spectral type B8 or later and with P<5 days, deviations from synchronism between rotation and revolution are small in 14 out of 15 cases. The average rotational velocity of the primaries in such systems is 75 km/sec, viz. only 40% of the average rotational velocity of single main-sequence stars in the same spectral region: (ii) primaries of spectral type earlier than B8 in systems with short as well as long periods tend to rotate more than twice as fast as one would expect from synchronism. A tentative explanation for these results is presented.
Binary Orbit Perturbations and the Rotational Angular Momentum of Stellar Interiors
Authors: Sobieski Stanley
Published: March 2018

Calculations show that a significant variation in the minima of eclipsing binaries should arise for systems where axial precession exists. Several different angular velocity distributions are assumed in order to estimate the expected photometric variation as a function of the model parameters. It is found that the solid body rotation approximation is a reasonable representation unless interiors rotate more rapidly than present models predict.
The Rotation of the Ap Stars From the Point of View of the Rigid Rotator Model
Authors: Preston George W.
Published: March 2018

Deutsch’s period vs. line-width relation for the periodic Ap stars is re-examined from the point of view of the rigid rotator with the aid of recently determined values of v sin i for these objects. The agreement between computed rotational velocities and observed values of v sin i is satisfactory if the radii of the Ap stars are twice those of zero-age main sequence stars of the same color. The computed rotational velocities also agree with the mean rotational velocities of all Ap stars if suitable allowances are made for observational limitations. However, a difficulty arises in connection with the number of ‘long-period’ stars that have been discovered. Their small computed rotational velocities and their frequency are such that they cannot be regarded as part of any rotational distribution function that describes normal stars or even most Ap stars. It is concluded that if the periods of these objects are rotational periods, then a powerful rotational deceleration mechanism must be operative in at least some Ap stars, primarily those of the SrCrEu group.
On the Equatorial Acceleration of the Sun
Authors: Roxburgh Ian W.
Published: March 2018

The interaction of rotation and turbulent convection gives rise to a latitude dependent turbulent energy transport. Energy conservation demands a slow meridional circulation in the solar outer convective zone. The transport of angular momentum by this circulation is balanced in a steady state by the turbulent viscous transport across an angular velocity gradient. Models are constructed which give equatorial acceleration as observed on the sun.
Spin Down of Boussinesq Fluid in the Circular Cylinder, as a Simulation of the Solar Spin-Down Procedure
Authors: Sakurai Takeo
Published: March 2018

As the simplest model to simulate the solar spin down procedure from the hydrodynamical viewpoint, a spin down problem with a simple geometrical configuration within the frame work of the Boussinesq approximation is investigated. A new proposal of the origin of the solar differential rotation is made on the basis of the calculated asymptotic distribution of the angular velocity. A comment on the present day solar spin down controversy is also made.
Seasonality and within-subject clustering of rotavirus infections in an eight-site birth cohort study
Authors: Colston J. M. , Ahmed A. M. S. , Soofi S. B. , Svensen E. , Haque R. , Shrestha J. , Nshama R. , Bhutta Z. , Lima I. F. N. , Samie A. , Bodhidatta L. , Lima A. A. M. , Bessong P. , Paredes Olortegui M. , Turab A. , Mohan V. R. , Moulton L. H. , Naumova E. N. , Kang G. , Kosek M. N. ,   The Mal-Ed network
Published: March 2018

Improving understanding of the pathogen-specific seasonality of enteric infections is critical to informing policy on the timing of preventive measures and to forecast trends in the burden of diarrhoeal disease. Data obtained from active surveillance of cohorts can capture the underlying infection status as transmission occurs in the community. The purpose of this study was to characterise rotavirus seasonality in eight different locations while adjusting for age, calendar time and within-subject clustering of episodes by applying an adapted Serfling model approach to data from a multi-site cohort study. In the Bangladesh and Peru sites, within-subject clustering was high, with more than half of infants who experienced one rotavirus infection going on to experience a second and more than 20% experiencing a third. In the five sites that are in countries that had not introduced the rotavirus vaccine, the model predicted a primary peak in prevalence during the dry season and, in three of these, a secondary peak during the rainy season. The patterns predicted by this approach are broadly congruent with several emerging hypotheses about rotavirus transmission and are consistent for both symptomatic and asymptomatic rotavirus episodes. These findings have practical implications for programme design, but caution should be exercised in deriving inferences about the underlying pathways driving these trends, particularly when extending the approach to other pathogens.
Whole-genome sequencing analysis of human bocavirus detected in South Korea
Authors: Kang L. H. , Won Y. J. , Lee A. R. , Lee S. G. , Cho H. G. , Park Y. J. , Han J. I. , Paik S. Y.
Published: March 2018

Human bocaviruses (HBoVs) have been detected in human gastrointestinal infections worldwide. In 2005, HBoV was also discovered in infants and children with infections of the lower respiratory tract. Recently, several genotypes of this parvovirus, including HBoV genotype 2 (HBoV2), genotype 3 (HBoV3) and genotype 4 (HBoV4), were discovered and found to be closely related to HBoV. HBoV2 was first detected in stool samples from children in Pakistan, followed by detection in other countries. HBoV3 was detected in Australia and HBoV4 was identified in stool samples from Nigeria, Tunisia and the USA. Recently, HBoV infection has been on the rise throughout the world, particularly in countries neighbouring South Korea; however, there have been very few studies on Korean strains. In this study, we characterised the whole genome and determined the phylogenetic position of CUK-BC20, a new clinical HBoV strain isolated in South Korea. The CUK-BC20 genome of 5184 nucleotides (nt) contains three open-reading frames (ORFs). The genotype of CUK-BC20 is HBoV2, and 98.77% of its nt sequence is identical with those of other HBoVs, namely Rus-Nsc10-N386. Especially, the ORF3 amino acid sequences from positions 212–213 and 454 corresponding to a variable region (VR)1 and VR5, respectively, showed genotype-specific substitutions that distinguished the four HBoV genotypes. As the first whole-genome sequence analysis of HBoV in South Korea, this information will provide a valuable reference for the detection of recombination, tracking of epidemics and development of diagnosis methods for HBoV.
New Confucianism, Science and the Future of the Environment
Authors: He Chengzhou
Published: March 2018

It is argued in this article that the dialogue between science and humanities is not just an option, but rather a necessary act. In China, New Confucianism has accomplished its creative transformation through its dialogue with science, and the development of science and technology has also benefited from humanities – New Confucianism included. In the global confrontation of growing environmental crisis, science alone cannot solve all the problems. What kind of role can New Confucianism play along with science in addressing the environmental issues? How will a re-interpretation of tianrenheyi (unity of man and nature), which is a core Confucian concept, contribute to the critique of anthropocentrism and the cross-cultural reformation of ecological thought? Bearing in mind both the cosmopolitan consciousness and the eco-environmental sensibility, a New Confucian ecological humanism is proposed and analysed in response to the global environmental problem.
Why Universities Better Invest in the Humanities
Authors: D’haen Theo
Published: March 2018

In the Western world, the humanities have been under pressure for the last two or three decades. There are various reasons for this, which have to do with the changed status of humanities disciplines within universities, but also with the public at large. Employment prospects are deemed slimmer for humanities graduates than for STEM graduates. Aging populations requiring more health and old age provisions, and globalization increasing economic competition, are leading to economization and rationalization in the world of academe, relegating the humanities often – quite naturally, so to speak – to the end of the funding chain. Still, there are good reasons to continue funding, and promoting, the humanities. These reasons have to do with questions of identity, but also of economics.*
The Identification of Particles in a Polymer Film Using Nano-Thermal Analysis
Authors: Grandy David , Kjoller Kevin
Published: March 2018

Nano-TA is a local thermal analysis technique that combines the high spatial resolution imaging capabilities of atomic force microscopy (AFM) with the ability to obtain understanding of the thermal behaviour of materials with a spatial resolution of sub-100nm. This breakthrough in spatial resolution of thermal analysis, which is ~50× better than previously reported, has profound implications for the fields of polymers and pharmaceuticals where local thermal understanding is key.

The conventional AFM tip is replaced by a special nano-TA probe that has an embedded miniature heater and is controlled by the specially designed nano-TA hardware and software. The nano-TA probe enables a surface to be visualised at nanoscale resolution using the routine imaging modes of AFM. The user is able to select the spatial locations for the investigation of the thermal properties of the surface. Heat is supplied locally via the probe tip and the thermomechanical response is measured.
Using the PMT in a Laser Scanning Confocal Microscope as a Digital Light Meter to Measure Detection Photon Efficiency
Authors: Pawley Jim
Published: March 2018

If we accept that the optical layouts of single-beam laser scanning confocals are generally quite similar, the most important variable is “Photon Efficiency” (PE): the fraction of photons leaving the focal plane that actually contribute to the number stored in the image memory. Unfortunately, this parameter is a function of a very large number of operator settings, design decisions and optical performance specifications (BioTechniques The 39 Steps; A Cautionary Tale about “quantitative” 3D fluorescence microscopy, April 2000 28:884-7). As a result, although all manufactures claim excellent “Photon Efficiency” none actually provide any specifications. We have to determine the PE ourselves.
Visualisation of Native Surfaces by Two-Step Molding
Authors: Gorb Stanislav N
Published: March 2018

One of the most important tasks of microscopy is to provide information about structures in their natural state. Since most life science microscopy procedures require fixation, dehydration, drying, and sectioning, diverse artefacts are unavoidable. It is also possible to dehydrate the water content of a specimen by freeze-drying. However, even relatively stable surface structures are changed during such treatments. Methods of liquid substitution and freezing-substitution show good results for biological specimens with a waxy solid coverage (Ensikat and Barthlott, 1993) and soft specimens in a mechanically deformed state (Gorb et al., 2000).

However, all these methods have certain restrictions for some types of specimens. For example, there are numerous biological surfaces covered with secretory fluids. Some specimens bear solid waxy coverings, which can be partly dissolved and washed out in organic solvents, such as ethanol, acetone, or propylenoxide. Often one would like to visualise dynamic processes (growth, deformation, or crystallisation) under environmental conditions, but at the high resolution in the SEM.
New Developments in Gemini® Fesem Technology
Authors: Jaksch H , Vermeulen J-P
Published: March 2018

The Field Emission SEM was introduced to improve imaging resolution available with conventional SEMs with a tungsten source. Thermal assisted or Schottky Field Emission SEMs were introduced in s the nineties by a number of companies as a stable source to overcome the beam instability of the cold FESEMs introduced earlier. The Gemini® based Field Emission SEM launched by Zeiss 12 years ago has been designed from the beginning as a high stability FESEM with a relatively large multi-ported chamber. The drive to develop Gemini® technology was the need for a FESEM capable of ultra-high resolution performance over the entire accelerating voltage range that also possessed the flexibility needed for a wide range of analytical applications.
Nondestructive, High-Resolution Materials Characterization with the Confocal Raman-AFM
Authors: Schmidt U , Jauss A , Ibach W , Weishaupt K , Hollricher O
Published: March 2018

Materials research, biomedical research, and semiconductor manufacturing can all benefit from nondestructive, high-resolution methods of analysis. As most materials are heterogeneous, it is important to not only acquire high resolution topographic information, but also to identify the chemical composition of samples. A combination of high resolution microscopy with chemically sensitive spectroscopy combined in one instrument allows the detailed characterization of samples with different analytical techniques. When individual instruments are used, returning to a previously surveyed sample area can be very time consuming if not impossible without surface markers.
How to Promote a Facility in Order to Increase Use, Acquire New Equipment and, as a Result, Increase Revenue
Authors: Humphrey Elaine , Sherman Debby
Published: March 2018

Promoting and maintaining a facility is a major concern to many of us. I had the pleasure last spring of participating in the 2nd International Cryo-workshop held in the Bio-Imaging Facility at the University of British Columbia. I talked to the facility director, Elaine Humphrey, and saw what she has done in a relatively short number of years in building that facility. I was incredibly impressed so I asked Elaine if she would address mis topic.

Elaine started out as a marine biologist in England and came across a problem that required electron microscopy. The first facility she went to was very discouraging saying that it was an extremely difficult technique. She managed to find another facility that made it easy.
Laboratory Design for High-Performance Electron Microscopy
Authors: O'Keefe Michael A , Turner John H , Musante John A , Hetherington Crispin JD , Cullis AG , Carragher Bridget , Jenkins Ron , Milgrim Julie , Milligan Ronald A , Potter Clinton S , Allard Lawrence F , Blom Douglas A , Degenhardt Lynn , Sides William H
Published: March 2018

Since publication of the classic text on the electron microscope laboratory by Anderson, the proliferation of microscopes with field emission guns, imaging filters and hardware spherical aberration correctors (giving higher spatial and energy resolution) has resulted in the need to construct special laboratories. As resolutions iinprovel transmission electron microscopes (TEMs) and scanning transmission electron microscopes (STEMs) become more sensitive to ambient conditions. State-of-the-art electron microscopes require state-of-the-art environments, and this means careful design and implementation of microscope sites, from the microscope room to the building that surrounds it. Laboratories have been constructed to house high-sensitive instruments with resolutions ranging down to sub-Angstrom levels; we present the various design philosophies used for some of these laboratories and our experiences with them. Four facilities are described: the National Center for Electron Microscopy OAM Laboratory at LBNL; the FEGTEM Facility at the University of Sheffield; the Center for Integrative Molecular Biosciences at TSRI; and the Advanced Microscopy Laboratory at ORNL.
TEM Sample Preparation Using Focused Ion Beam - Capabilities And Limits
Authors: Engelmann HJ , Volkmann B , Ritz Y , Saage H , Stegmann H , de Robiliard Q , Zschech E
Published: March 2018

TEM sample preparation using Focused Ion Beam (FIB) methods becomes more and more interesting for microscopists because the technique allows for reliable and very efficient sample preparation. The first application of TEM sample preparation by FIB-cutting was reported more than 10 years ago. Meanwhile, a lot of experience has been gathered that allows one to discuss the capabilities and limits of the FIB technique in detail.

Several TEM sample preparation techniques are known that all include FIB-cutting but differ in sample pre-preparation, sample handling, etc. This paper focuses on the actual FIB process, FIB tools are closely related to Scanning Electron Microscopes, but instead of an electron beam an ion beam (mostly Ga+ ions) is used to remove and deposit material.
How to Recognize and Avoid AFM Image Artifacts
Authors: West Paul , Starostina Natalia
Published: March 2018

Images produced by an atomic forces microscope (AFM) often contain spurious features and image distortion that can render accurate imaging and metrology suspect. These “artifacts” are caused by the manner in which the image is produced. Artifacts can originate from the probe tip geometry, scanner non-linearity, image processing software, vibration, sample contamination, electronic noise, and poor sample stability. This article describes and illustrates common AFM image artifacts and suggests means to eliminate or minimize them.
Microscopy of Silicified Wood
Authors: Mustoe George
Published: March 2018

Ancient forests comprised an enormous biomass and typically flourished in lowland habitats that offered favorable conditions for fossllization, so it is not surprising that petrified wood is the most abundant terrestrial fossil. Petrifaction of wood by carbonates, sulfides, oxides, and phosphates is evidence that fossilization can occur under diverse geochemical conditions, but silicification is by far the most common process.
Microwave Processing in Diagnostic Electron Microscopy
Authors: Gerrity Ross G , Forbes George W
Published: March 2018

Transmission electron microscopy (TEM) continues to play an important role in diagnostic surgical pathology, particularly in such areas as kidney pathology and tumor diagnosis, among others. Diagnostic TEM is subject to unique time constraints, quality control regulations, and other problems not seen in other TEM applications. The diagnostic TEM laboratory must produce high-quality electron microscopy on small samples which frequently are suboptirnal in fixation and tissue quality due to the pathology involved and time factors associated with biopsy and surgery.
Colocalization of Fluorescent Probes Using Image-Pro® Plus v. 5.0
Authors: Casavan Will , Gaidoukevitch Yuri
Published: March 2018

Fluorescence labeling techniques are quite useful to microscopists. Not only can fluorescent probes label sub-cellular structures with a high degree of specificity, they can also do so with a very high degree of sensitivity. This combination of specificity and sensitivity permits observations of cellular events that are not always visible using traditional methodologies, such as brightfield microscopy.
Practical Issues for Quantitative X-ray Microanalysis in SEM at Low kV
Authors: Statham Peter
Published: March 2018

In the three decades following Castaing's seminal thesis [1] x-ray analysis received widespread attention from research groups. By 1980, the methods and correction procedures for quantitative analysis of elements with atomic number 11 and above, using accelerating voltages between 15kV and 25kV, were well established and available in commercial instrumentation. At the time, scanning electron microscopes (SEMs) could rarely deliver high and stable beam current at much lower kV, and x-ray spectrometers had poor efficiency below lkeV so that low kV analysis received comparatively little attention.
Ethics and Digital Imaging
Authors: Mackenzie J M , Burke M G , Carvalho T , Eades A
Published: March 2018

The amazing growth of digital imaging in the past several years has blurred the line between "real" images and those that are digitally enhanced. In most of our movies and print advertisements, we see amazing effects that create images that look real but are not.

For the last several decades film has been the predominant method that scientists employ to record the images viewed through their microscopes. Film has been readily accepted as a valid, archival recording medium because it was difficult to alter once the exposure was made and the film or print developed. The improvements in computer power and image resolution, coupled with environmental considerations, have spurred the scientific community to replace photographic processes with digital images. Processes that took hours and days are now performed in minutes. Imaging programs like Adobe Photoshop can perform all of the same photographic steps that required a darkroom, and then can do much more. The image can be “burned” onto a CD or DVD disk which is difficult to alter. Printer technology has advanced so rapidly that inkjet prints rival photographic prints. Images are often distributed digitally and viewed on displays that continue to improve. As the hardware for digital imaging improves, the quality of digital images is approaching photographic quality for a fraction of the cost, and publication quality images are produced in a fraction of the time required for film-based photography.
Some Considerations for EM Cooling Systems
Authors: Mitchell Allan
Published: March 2018

For numerous reasons a closed-circuit water cooling system is the preferred option for providing cooling water to the electron microscope. Cooling water is required by the electron microscope to cool the diffusion pumps and to keep the electronics' and coiumn temperature stable.

A closed-circuit water cooling system is essential if the local water supply has a high chloride concentration, has floating particles, is acidic, has a water temperature that fluctuates and is uncontrollable. This potentially leads to specimen drift problems in the TEW, and/or has a water temperature that is very cold. This potentially leads to condensation problems or diffusion pumps not functioning properly in the TEM.
X-Ray Analysis in a Vacuum?
Authors: Chernoff Don
Published: March 2018

Performing X-ray analysis on a sample in an SEM used to be relatively straightforward. Straightforward and not always very exciting. Things have gotten a lot more interesting, In jus! the past few years, the amazing development oi variable pressure SEMs has revolutionized the way we can look at samples. At the same time these new machines have changed the way we can image samples, they have also affected how we perform X-ray analysis on those samples.

I apologize in advance for the following gross simplification. For quite a lot of samples, the point and click method of X-ray analysis was and is sufficient to get meaningful data from a sample. Put the beam on a feature, collect a spectrum, and move onto the next sample.
Preparation of Geological and Biological TEM Specimens by Embedding in Sulfur
Authors: Hugo Richard C , Cady Sherry L
Published: March 2018

The technique of embedding TEM specimens in polymer resins for subsequent ultra-thin sectioning is well established. For geological materials, this protocol prevents specimen damage introduced by ion beam thinning, and is often used for preparing friable or porous materials. However, traditional polymer-based embedding resins may introduce organic carbon contaminants, producing artifacts in carbon analyses. Thus, a carbon-free substitute for traditional embedding media is required to ensure accurate carbon analyses of embedded and ultramicrotomed TEM specimens.

A suitable technique that was first reported by Bradley is to embed specimens in pure sultur. In this technique, the specimen is immersed in liquid sulfur, the liquid is solidified, and the resulting block is ultramicrotomed as with traditional resins. Since sulfur has a high vapor pressure at room temperature, the ultra-thin sections are then placed in a separate vacuum chamber to sublimate the sulfur, yielding TEM specimens free of any embedding medium.
Glutaraldehyde Autofluorescence Useful in Confocal Studies of Fungi
Authors: Singh Adya , Xiao Ying , Wakeling Robin
Published: March 2018

In this note we show the potential usefulness of glutaraldehyde (GA) in confocai microscopic studies of wood-fungal interaction. We are presently developing methods to examine by the confocai laser scanning microscope (CLSM), the pattern of distribution of fungal hyphae within wood in relation to fungal degradation and sapstaining of wood. CLSM has the potential to be a very useful tool in such studies for a variety of reasons, including its use for optical sectioning to produce computer assisted 3-D images.
A Method for Decapsulting Integrated Circuit Chips
Authors: Holdford Becky
Published: March 2018

Questions have arisen recently on the Microscopy Listserver about the best way to decapsulate integrated circuit chips. Here is the method that has been developed at the Dallas Device Analysis Operation of Texas Instruments, inc., and is used by many laboratories here. We find that it works very well.
Formaldehyde, Formalin, Paraformaldehyde And Glutaraldehyde: What They Are And What They Do
Authors: Kiernan John A
Published: March 2018

Aldehydes are the most commonly used fixatives. They serve to stabilize the fine structural details of cells and tissues prior to examination by light or electron microscopy. Research workers, technicians, pathologists and others who regularly use aldehyde fixatives frequently do not appreciate the nature and properties of these compounds or the reasons for choosing to fix a specimen in formaldehyde, glutaraldehyde or a mixture of the two. Misconceptions are widespread also about formalin and paraformaldehyde, the commercial products from which formaldehyde-containing solutions are made.
Watching Neurons Hand Off Molecules
Authors: Carmichael Stephen W
Published: March 2018

Since the discovery of nerve growth factor, it has been thought that neurotrophic factors are released or secreted from target cells. However, more recently it has been suggested that a specific neurotrophic factor known as brain-derived neurotrophic factor (BDNF) may reach target cells directly from presynaptic axons. It has not been known how these molecules get from the neuron in which they are produced to the target cells. Keigo Kohara, Akihiko Kitamura, Mieko Morishima, and Tadaharu Tsumoto have demonstrated that BDNF is transported anterogradely from presynaptic neurons to target neurons.
Novel Use of Fluorescence Illumination with an Infrared Microscope
Authors: Tague Thomas J , Miller Lisa M
Published: March 2018

It has become increasingly obvious that infrared microspectroscopy can be the analysis tool of choice when determining the chemical composition of biological and biomedical samples. Frequently, fluorescence illumination is required for sample characterization, which previously required the use of a separate optical microscope. There has also been a need in the semiconductor manufacturing industry for a single tool for visualizing particle contaminants on integrated wafers as well as the ability to chemically determine their nature. There is now a single microscope platform for conducting rapid Nomarski differential interference contrast and fluorescence illumination sample visualization as well as infrared analysis. This novel infrared microscope has applicability to many fields of investigation, including pharmacology, forensics, cell biology, histology, gemology, and geology.
Low Voltage Scanning Electron Microscopy and Jack Ramsey's principle
Authors: Wells Oliver C
Published: March 2018

“Low Voltage Scanning Electron Microscopy (LVSEM), defined as operation in the energy range below 5 keV” was described by David Joy and Dale Newbury (1) in the previous issue of this journal as being “perhaps the most important single operational mode of the SEM.” In their paper they describe both the advantages and disadvantages of this method.

Ramsey's principle, which was established by Jack Ramsey over many years as a microscopist and microanalyst, is to say: “There is no best way of doing ANYTHING.”
Training in Forensic Microscopy
Authors: Chapin William
Published: March 2018

The world of forensic microscopy is complex and challenging. There is a never-ending variety of requested examinations and consequently, the analyst is often asked to work in an area of little familiarity. Adding to the challenge is the inherent problem of having no exact information as to the condition of the sample prior to the crime. The forensic microscopist is expected to have mastered proficiency in polarized light microscopy in order to identify fibers, minerals, insect parts, woods, metals, biological fluids, pollution particles, microchemical techniques, paints, pigments, pollens, drugs, explosives, diatoms, safe insulation, etc. and to compare samples of all the these plus hairs, glass, etc., etc.
Retention of Calcium and Other Ions for Microanalysis by Freeze-Drying
Authors: Ryan Keith P , Berry Lorraine S
Published: March 2018

Calcium (Ca++) and other diffusible ions cannot be preserved for x-ray microanalysis if specimens have been preserved by fixation using formaldehyde, glutaraldehyde or other fixatives. Atoms, such as Ca, are not diffusible when they are bound to something insoluble, such as bone or hard granules in cells which are sometimes mechanisms for detoxifying. Ions, loosely bound elements and other components such as sugars and amino acids are leached out during chemical fixation and dehydration by solvents. This problem was recognized over a hundred years ago by Richard Altmann. An alternative to wet chemical processing is the purely physical method that involves rapidly freezing the specimen and then removing the frozen water by the process of freeze drying, which is the subject of this article.
Optimal Noise Filters in High-Resolution Electron Microscopy
Authors: Ishizuka Kazuo , Eilers Paul H C , Kogure Toshihiro
Published: March 2018

Most of the specimens for high-resolution electron microscopy have amorphous surface layers due to contamination during observation and/or damaged surface layers during specimen preparation. Moreover, many specimens are radiation sensitive, and a part of the specimen easily becomes amorphous during the observation. These amorphous materials make clear observation of crystal structure difficult. A periodic structure may be extracted by simply using a periodic mask in Fourier space. However, this kind of mask often introduces a periodic feature in addition to the crystal structure. To reduce such artifacts a Wiener filter or an average background subtraction filter has been discussed. However, these filters do not work for non-ideal crystals, such as cylindrical crystals and nano-crystals, where a translational periodicity is limited to the order of nano-meter. In this report we improve these filters by introducing new ways to estimate a contribution from the amorphous materials.
Overcoming Challenges in Material Science Testing with the use of Large Specimen SEM Analysis
Authors: Romero Adriana
Published: March 2018

One of the most oft-confronted challenges in materials science, when using scanning electron microscopy, is the limitation of the size of the sample being examined, as well as the analysis application planned. Normally, only small samples in the order of ten to a hundred millimetres in diameter may be investigated. In addition, until now, conventional high-load fatigue testing inside a scanning electron microscope (SEM) seemed impossible. Nevertheless, SEM testing is a very valuable method in the fields of material and biological science as well as in quality control and failure analysis. For many technological interesting applications, conventional scanning electron microscopy is not possible because the specimens that need to be investigated cannot be destroyed for the SEM investigations for one of several reasons. It maybe that the specimen must be kept whole so that it can be returned to a production line or perhaps the specimen is an object of historic and/or artistic interest and value.
Beyond Death: Forensic Investigations of pre-Columbian Mummies from the Tarapacá Valley, Chile, Using Variable Pressure SEM and Raman Spectroscopy
Authors: Prikhodko SV , Fischer C , Boytner R , Lozada M C , Uribe M , Kakoulli I
Published: March 2018

Variable pressure scanning electron microscopy (VPSEM) coupled with other non-destructive analytical methods, such as energy dispersive (EDS) and Raman spectroscopy (RS) offers new capabilities for non-invasive imaging and chemical characterization of archaeological materials. This article underlines the application of VPSEM-EDS-RS on bioarchaeological specimens of pre-Columbian mummies from the Tarapacá Valley in northern Chile. The aim of the scientific investigations is to identify nonanatomical features and to provide qualitative and quantitative information at molecular levels, complementing the morphological record from studies in physical anthropology, in an effort to understand mortuary practices in the Tarapacá Valley and the effects of the burial environment in the preservation of mummified human remains.
Methods for Casting Ancient Bone and Teeth for Viewing under the SEM
Authors: Schmidt Christopher W
Published: March 2018

While using casts in place of original bones and teeth for study with the SEM is a rather common practice, periodic updates and introductions of unique casting methods help to keep the process of improving cast quality cumulative, limiting unnecessary repetition of ineffectual procedures. The following is a summary of casting methods that I have synthesized from several published reports as well as some that I have developed independently (e.g., Waters and Savage 1971; Scott 1982; Rose 1983; Gordon 1984; Teaford 1991; Buikstra and Ubelaker 1994; Schmidt, 1998). The study for which I first employed these methods consisted of hundreds of archeologically- derived human teeth dating from about 1,000 to around 10,000 years ago. The study required detailed views of dental surfaces magnified 500X (Figure 1). The casts that I produced routinely had features that were distinct at magnifications of 2.000X and higher.