Toward a Comprehensive Approach to the Collection and Analysis of Pica Substances, with Emphasis on Geophagic Materials

Pica, the craving and subsequent consumption of non-food substances such as earth, charcoal, and raw starch, has been an enigma for more than 2000 years. Currently, there are little available data for testing major hypotheses about pica because of methodological limitations and lack of attention to the problem.In this paper we critically review procedures and guidelines for interviews and sample collection that are appropriate for a wide variety of pica substances. In addition, we outline methodologies for the physical, mineralogical, and chemical characterization of these substances, with particular focus on geophagic soils and clays. Many of these methods are standard procedures in anthropological, soil, or nutritional sciences, but have rarely or never been applied to the study of pica.Physical properties of geophagic materials including color, particle size distribution, consistency and dispersion/flocculation (coagulation) should be assessed by appropriate methods. Quantitative mineralogical analyses by X-ray diffraction should be made on bulk material as well as on separated clay fractions, and the various clay minerals should be characterized by a variety of supplementary tests. Concentrations of minerals should be determined using X-ray fluorescence for non-food substances and inductively coupled plasma-atomic emission spectroscopy for food-like substances. pH, salt content, cation exchange capacity, organic carbon content and labile forms of iron oxide should also be determined. Finally, analyses relating to biological interactions are recommended, including determination of the bioavailability of nutrients and other bioactive components from pica substances, as well as their detoxification capacities and parasitological profiles.This is the first review of appropriate methodologies for the study of human pica. The comprehensive and multi-disciplinary approach to the collection and analysis of pica substances detailed here is a necessary preliminary step to understanding the nutritional enigma of non-food consumption

A new approach to synchrotron energy-dispersive X-ray diffraction computed tomography

A new data collection strategy for performing synchrotron energy-dispersive X-ray diffraction computed tomography has been devised. This method is analogous to angle-dispersive X-ray diffraction whose diffraction signal originates from a line formed by intersection of the incident X-ray beam and the sample. Energy resolution is preserved by using a collimator which defines a small sampling voxel. This voxel is translated in a series of parallel straight lines covering the whole sample and the operation is repeated at different rotation angles, thus generating one diffraction pattern per translation and rotation step. The method has been tested by imaging a specially designed phantom object, devised to be a demanding validator for X-ray diffraction imaging. The relative strengths and weaknesses of the method have been analysed with respect to the classic angle-dispersive technique. The reconstruction accuracy of the method is good, although an absorption correction is required for lower energy diffraction because of the large path lengths involved. The spatial resolution is only limited to the width of the scanning beam owing to the novel collection strategy. The current temporal resolution is poor, with a scan taking several hours. The method is best suited to studying large objects (e.g. for engineering and materials science applications) because it does not suffer from diffraction peak broadening effects irrespective of the sample size, in contrast to the angle-dispersive case

Data from: Sustained fitness gains and variability in fitness trajectories in the long-term evolution experiment with Escherichia coli

Many populations live in environments subject to frequent biotic and abiotic changes. Nonetheless, it is interesting to ask whether an evolving population's mean fitness can increase indefinitely, and potentially without any limit, even in a constant environment. A recent study showed that fitness trajectories of Escherichia coli populations over 50 000 generations were better described by a power-law model than by a hyperbolic model. According to the power-law model, the rate of fitness gain declines over time but fitness has no upper limit, whereas the hyperbolic model implies a hard limit. Here, we examine whether the previously estimated power-law model predicts the fitness trajectory for an additional 10 000 generations. To that end, we conducted more than 1100 new competitive fitness assays. Consistent with the previous study, the power-law model fits the new data better than the hyperbolic model. We also analysed the variability in fitness among populations, finding subtle, but significant, heterogeneity in mean fitness. Some, but not all, of this variation reflects differences in mutation rate that evolved over time. Taken together, our results imply that both adaptation and divergence can continue indefinitely—or at least for a long time—even in a constant environment

The healthcare of older inmates in the correctional setting

Australia, like other western nations, is experiencing a new trend within its prison population - the ageing inmate. This \u27greying\u27 of the population presents a unique challenge for the correctional environment. Specific needs of this population may not be well met within a correctional facility due to the physical environment layout and surroundings, restricted health service access and unaccommodating facilities and programmes. This is compounded by limited visits from family and friends. This paper outlines some of the general needs of the older male inmate and the difficulties this poses for correctional and health services. Current international initiatives and programmes used to address the ageing population\u27s needs are briefly examined, as are the implications for Australian and international correctional and health services wishing to implement such schemes. The applicability of Government Legislation, pertaining to the standards of care in the community, to correctional aged care programmes and facilities is discussed

Investigating the impact of the COVID-19 pandemic on recovery colleges: multi-site qualitative study

Background During the COVID-19 pandemic, mental health problems increased as access to mental health services reduced. Recovery colleges are recovery-focused adult education initiatives delivered by people with professional and lived mental health expertise. Designed to be collaborative and inclusive, they were uniquely positioned to support people experiencing mental health problems during the pandemic. There is limited research exploring the lasting impacts of the pandemic on recovery college operation and delivery to students. Aims To ascertain how the COVID-19 pandemic changed recovery college operation in England. Method We coproduced a qualitative interview study of recovery college managers across the UK. Academics and co-researchers with lived mental health experience collaborated on conducting interviews and analysing data, using a collaborative thematic framework analysis. Results Thirty-one managers participated. Five themes were identified: complex organisational relationships, changed ways of working, navigating the rapid transition to digital delivery, responding to isolation and changes to accessibility. Two key pandemic-related changes to recovery college operation were highlighted: their use as accessible services that relieve pressure on mental health services through hybrid face-to-face and digital course delivery, and the development of digitally delivered courses for individuals with mental health needs. Conclusions The pandemic either led to or accelerated developments in recovery college operation, leading to a positioning of recovery colleges as a preventative service with wider accessibility to people with mental health problems, people under the care of forensic mental health services and mental healthcare staff. These benefits are strengthened by relationships with partner organisations and autonomy from statutory healthcare infrastructures

Simultaneous X-ray diffraction, crystallography and fluorescence mapping using the Maia detector

© 2017 Acta Materialia Inc. Interactions between neighboring grains influence the macroscale behavior of polycrystalline materials, particularly their deformation behavior, damage initiation and propagation mechanisms. However, mapping all of the critical material properties normally requires that several independent measurements are performed. Here we report the first grain mapping of a polycrystalline foil using a pixelated energy-dispersive X-ray area detector, simultaneously measuring X-ray fluorescence and diffraction with the Maia detector in order to determine grain orientation and estimate lattice strain. These results demonstrate the potential of the next generation of X-ray area detectors for materials characterization. By scanning the incident X-ray energy we investigate these detectors as a complete solution for simultaneously mapping the crystallographic and chemical properties of the sample. The extension of these techniques to broadband X-ray sources is also discussed

Mutation.Rate.Data

This file contains the mutation rate data from the fluctuation tests in Table S8 in the manuscript

All.Hands.Concatenated.Data

This data file contains all of the plate counts for all of the fitness measurements within this paper

All.Hands.Revised.Submission

This is the revised analysis script, adding a section at the end to include an additional analysis requested by a reviewer