76 research outputs found

    Spatial resolution limits of EPMA

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    The human right to a healthy environment—time for the public health community to take urgent action

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    With growing recognition of the extent to which human activities are imperilling planetary health, it is critical to understand how international law can uphold a healthy environment. Drawing from 50 years of dedicated diplomacy, the United Nations General Assembly has recognised the right to a clean, healthy, and sustainable environment under international law.1 The July 2022 resolution responds to the urgent dangers posed by climate change, environmental degradation, and bio-diversity loss. The public health community should seize the opportunity to implement this new right to promote planetary health

    Decontamination in Electron Probe Microanalysis with a Peltier-Cooled Cold Finger

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    AbstractA prototype Peltier thermoelectric cooling unit has been constructed to cool a cold finger on an electron microprobe. The Peltier unit was tested at 15 and 96 W, achieving cold finger temperatures of −10 and −27°C, respectively. The Peltier unit did not adversely affect the analytical stability of the instrument. Heat conduction between the Peltier unit mounted outside the vacuum and the cold finger was found to be very efficient. Under Peltier cooling, the vacuum improvement associated with water vapor deposition was not achieved; this has the advantage of avoiding severe degradation of the vacuum observed when warming up a cold finger from liquid nitrogen (LN2) temperatures. Carbon contamination rates were reduced as cooling commenced; by −27°C contamination rates were found to be comparable with LN2-cooled devices. Peltier cooling, therefore, provides a viable alternative to LN2-cooled cold fingers, with few of their associated disadvantages.</jats:p

    Evaluating X-Ray Microanalysis Phase Maps Using Principal Component Analysis

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    AbstractAutomated phase maps are an important tool for characterizing samples but the data quality must be evaluated. Common options include the overlay of phases on backscattered electron (BSE) images and phase composition averages and standard deviations. Both these methods have major limitations. We propose two methods of evaluation involving principal component analysis. First, a red–green–blue composite image of the first three principal components, which comprise the majority of the chemical variation, which provides a good reference against which phase maps can be compared. Advantages over a BSE image include discriminating between similar mean atomic number phases and sensitivity across the entire range of mean atomic numbers present in a sample. Second, principal component maps for identified phases, to examine for chemical variation within phases. This ensures the identification of unclassified phases and provides the analyst with information regarding the chemical heterogeneity of phases (e.g., chemical zoning within a mineral or mineral chemistry changing across an alteration zone). Spatial information permits a good understanding of heterogeneity within a phase and allows analytical artifacts to be easily identified. These methods of evaluation were tested on a complex geological sample. K-means clustering and K-nearest neighbor algorithms were used for phase classification, with the evaluation methods demonstrating their limitations.</jats:p

    The human right to a healthy environment—time for the public health community to take urgent action

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    The public health community should urgently leverage the human right to a healthy environment to protect planetary health, argue Kent Buse and colleagues

    Impact of headache frequency and preventive medication failure on quality of life, functioning, and costs among individuals with migraine across several European countries: need for effective preventive treatment

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    Healthcare costs; Migraine; Treatment failureCostos d'atenció mèdica; Migranya; Fracàs del tractamentCostos de atención médica; Migraña; Fracaso del tratamientoBackground Data are limited regarding the combined impact of headache frequency and failure of preventive medication (efficacy and/or tolerability) on the humanistic/economic burden of migraine. Methods A retrospective, cross-sectional analysis of 2020 National Health and Wellness Survey (NHWS) data was conducted. An opt-in online survey identified adults in France, Germany, Italy, Spain, and United Kingdom with self-reported physician-diagnosed migraine. Participants with ≥ 4 monthly headache days (MHDs) were stratified by prior preventive medication use/failure (preventive naive; 0–1 failure; ≥ 2 failures). Quality-of-life and economic outcomes were compared among groups using generalized linear modeling. Results Among individuals with ≥ 4 MHDs (n = 1106), the NHWS identified 298 (27%) with ≥ 2 failures, 308 (28%) with 0–1 failure, and 500 (45%) as preventive naive. Individuals with ≥ 2 failures versus preventive-naive individuals had significantly lower scores on the 12-Item Short Form Survey Physical Component Summary (42.2 vs 44.1; P < 0.005), numerically higher scores on the Mental Component Summary (39.5 vs 38.5; P = 0.145), significantly higher scores on the Migraine Disability Assessment (39.1 vs 34.0; P < 0.05), and significantly higher prevalence of depression symptoms (62% vs 47%; P < 0.001) and anxiety symptoms (42% vs 31%; P < 0.01). The ≥ 2 failures group versus the preventive-naive group also had significantly more functional impairment as assessed by mean numbers of migraine-specific missed work days (7.8 vs 4.3) and household activities days (14.3 vs 10.6) in the past 6 months (P < 0.001) as well as the prevalence of absenteeism (19% vs 13%), overall work impairment (53% vs 42%), and activity impairment (53% vs 47%) (all P < 0.05). Emergency department visits (0.7 vs 0.5; P = 0.001) and hospitalizations (0.5 vs 0.3; P < 0.001) in the past 6 months were significantly higher in the ≥ 2 failures group versus the preventive-naive group, while indirect costs (€13,720 vs €11,282) and the proportion of individuals with non-adherence during the past 7 days (73% vs 64%) were numerically higher. Conclusions Increased burden, quality-of-life impairment, and functional impairment exist among individuals with migraine experiencing ≥ 4 MHDs and more treatment failures. While cause and directionality cannot be determined, these results suggest the need for effective preventive migraine treatments.Allergan (prior to its acquisition by AbbVie) funded this study and participated in the study design, research, analysis, data collection, interpretation of data, reviewing, and approval of the publication. All authors had access to relevant data and participated in the drafting, review, and approval of this publication. No honoraria or payments were made for authorship

    Hair Cortisol and Perceived Stress-Predictors for the Onset of Tics?:A European Longitudinal Study on High-Risk Children

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    Some retrospective studies suggest that psychosocial stressors trigger the onset of tics. This study examined prospective hypothalamic-pituitary-adrenal (HPA) axis activity and perceived stress prior to tic onset. In the present study, 259 children at high risk for developing tics were assessed for hair cortisol concentration (HCC) and parent-on-child-reported perceived stress four-monthly over a three-year period. We used (i) generalised additive modelling (GAM) to investigate the time effects on HCC (hair samples n = 765) and perceived stress (questionnaires n = 1019) prior to tic onset and (ii) binary logistic regression to predict tic onset in a smaller subsample with at least three consecutive assessments (six to nine months before, two to five months before, and at tic onset). GAM results indicated a non-linear increasing course of HCC in children who developed tics, and a steady HCC course in those without tics, as well as a linear-increasing course of perceived stress in both groups. Logistic regression showed that with a higher HCC in hair samples collected in a range of two to five months before tic onset (which refers to cortisol exposure in a range of four to eight months), the relative likelihood of tic onset rose. Our study suggests increased stress prior to tic onset, as evidenced by higher HCC several months before tic onset. </p

    Chamber formation leads to Mg/Ca banding in the planktonic foraminifer <i>Neogloboquadrina pachyderma</i>

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    Many species of planktonic foraminifera show distinct banding in the intratest distribution of Mg/Ca. This heterogeneity appears biologically controlled and thus poses a challenge to Mg/Ca paleothermometry. The cause of this banding and its relation with chamber formation are poorly constrained and most of what we know about intratest Mg/Ca variability stems from culture studies of tropical, symbiont-bearing foraminifera. Here we present data on the non-spinose, symbiont-barren Neogloboquadrina pachyderma from the subpolar North Atlantic where wintertime mixing removes vertical gradients in temperature and salinity. This allows investigation of biologically controlled Mg/Ca intratest variability under natural conditions. We find that intratest Mg/Ca varies between <0.1 and 7 mmol/mol, even in winter specimens. High Mg/Ca bands occur at the outer edge of the laminae, indicating reduced Mg removal at the end of chamber formation. Our data thus provide new constraints on the timing of the formation of such bands and indicate that their presence is intrinsic to the chamber formation process. Additionally, all specimens are covered with an outer crust consisting of large euhedral crystals. The composition of the crust is similar to the low Mg/Ca bands in the laminar calcite in winter and summer specimens, indicating a tight biological control on crust formation and composition. Nevertheless, despite high intratest variability, the median Mg/Ca of summertime tests is higher than that of wintertime tests. This provides support for Mg/Ca paleothermometry, but to improve the accuracy of paleotemperature estimates biological effects on Mg incorporation need to be better accounted fo

    Caryl Churchill’s 21st Century Poetics: Theatre form and feminism from far away to Ding Dong the Wicked

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    This article considers the six 21st century plays Caryl Churchill has written up to 2012: Far Away, A Number, Drunk Enough to Say I Love You?, Seven Jewish Children, Love and Information and Ding Dong the Wicked. It considers each in relation to the vision of feminist theatre offered in Sue-Ellen Case's classic 1998 study Feminism and Theatre to consider how far the aims and values of second wave feminism remain evident in Churchill’s 21st century work. Through this discussion the article attempts to more sharply define the formal characteristics of each play and their relationship to its subject matter, and to place this discussion in the context of contemporary notions of the 'post-feminist' and of 'feminist residue'. It is one of the first scholarly considerations of Love and Information and Ding Dong the Wicked, both first performed in 2012
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