85 research outputs found
Argon behaviour in an inverted Barrovian sequence, Sikkim Himalaya: the consequences of temperature and timescale on <sup>40</sup>Ar/<sup>39</sup>Ar mica geochronology
40Ar/39Ar dating of metamorphic rocks sometimes yields complicated datasets which are difficult to interpret in terms of timescales of the metamorphic cycle. Single-grain fusion and step-heating data were obtained for rocks sampled through a major thrust-sense shear zone (the Main Central Thrust) and the associated inverted metamorphic zone in the Sikkim region of the eastern Himalaya. This transect provides a natural laboratory to explore factors influencing apparent 40Ar/39Ar ages in similar lithologies at a variety of metamorphic pressure and temperature (P–T) conditions.
The 40Ar/39Ar dataset records progressively younger apparent age populations and a decrease in within-sample dispersion with increasing temperature through the sequence. The white mica populations span ~ 2–9 Ma within each sample in the structurally lower levels (garnet grade) but only ~ 0–3 Ma at structurally higher levels (kyanite-sillimanite grade). Mean white mica single-grain fusion population ages vary from 16.2 ± 3.9 Ma (2σ) to 13.2 ± 1.3 Ma (2σ) from lowest to highest levels. White mica step-heating data from the same samples yields plateau ages from 14.27 ± 0.13 Ma to 12.96 ± 0.05 Ma. Biotite yield older apparent age populations with mean single-grain fusion dates varying from 74.7 ± 11.8 Ma (2σ) at the lowest structural levels to 18.6 ± 4.7 Ma (2σ) at the highest structural levels; the step-heating plateaux are commonly disturbed.
Temperatures > 600 °C at pressures of 0.4–0.8 GPa sustained over > 5 Ma, appear to be required for white mica and biotite ages to be consistent with diffusive, open-system cooling. At lower temperatures, and/or over shorter metamorphic timescales, more 40Ar is retained than results from simple diffusion models suggest. Diffusion modelling of Ar in white mica from the highest structural levels suggests that the high-temperature rocks cooled at a rate of ~ 50–80 °C Ma− 1, consistent with rapid thrusting, extrusion and exhumation along the Main Central Thrust during the mid-Miocene
Dietary nitrate supplementation increases fractional exhaled nitric oxide: implications for the assessment of airway health in athletes
Background: Fractional exhaled nitric oxide (FeNO) is a simple tool that has an established role in the assessment of airway inflammation in athletes. Specifically, FeNO provides information concerning asthma phenotypes, aetiology of respiratory symptoms, response to anti-inflammatory agents, course of disease and adherence to medication. It is recognised that FeNO can be influenced by a variety of external factors (e.g. atopic status, exercise, respiratory tract infection), however, there remains limited research concerning the impact of dietary nitrate ingestion. The primary aim of this study was therefore to evaluate the effect of acute dietary nitrate supplementation on FeNO and resting pulmonary function parameters. Method: The study was conducted as a randomised double-blind placebo-controlled trial. Thirty male endurance trained athletes (age: 28 ± 6 yrs; BMI: 23 ± 2 kg.m-2) free from cardio-respiratory and metabolic disease, and stable at time of study entry (i.e. entirely asymptomatic without recent respiratory tract infection) attended the laboratory on two separate occasions. On arrival to the laboratory, athletes consumed either 140ml nitrate-rich beetroot juice (15.2 mmol nitrate) (NIT) or nitrate-depleted beetroot juice (0 mmol nitrate) (PLA). In accordance with international guidelines all athletes performed resting FeNO and forced spirometry (2.5hrs post ingestion). Airway inflammation was evaluated using established FeNO thresholds: (intermediate [≥25ppb] and high [>50ppb]). Results: All athletes demonstrated normal baseline lung function (FEV1 % predicted >80%). A three-fold rise in resting FeNO was observed following NIT (median [IQR]): 32ppb [37] in comparison to PLA: 10ppb [12] (P0.05). Conclusion: Dietary nitrate ingestion should be considered when employing FeNO for the assessment of airway health in athletes. Our findings have implications concerning the decision to initiate or modify inhaler therapy. Further research is therefore required to determine the impact of chronic dietary nitrat
Gluttony, excess, and the fall of the planter class in the British Caribbean
Food and rituals around eating are a fundamental part of human existence. They can also be heavily politicized and socially significant. In the British Caribbean, white slaveholders were renowned for their hospitality towards one another and towards white visitors. This was no simple quirk of local character. Hospitality and sociability played a crucial role in binding the white minority together. This solidarity helped a small number of whites to dominate and control the enslaved majority. By the end of the eighteenth century, British metropolitan observers had an entrenched opinion of Caribbean whites as gluttons. Travelers reported on the sumptuous meals and excessive drinking of the planter class. Abolitionists associated these features of local society with the corrupting influences of slavery. Excessive consumption and lack of self-control were seen as symptoms of white creole failure. This article explores how local cuisine and white creole eating rituals developed as part of slave societies and examines the ways in which ideas about hospitality and gluttony fed into the debates over slavery that led to the dismantling of slavery and the fall of the planter class
Using Geonarratives to Explore the Diverse Temporalities of Therapeutic Landscapes: Perspectives from “Green” and “Blue” Settings
This is the author accepted manuscript. The final version is available from Taylor and Francis via the DOI in this record.A growing evidence base highlights “green” and “blue” spaces as examples of
“therapeutic landscapes” incorporated into people’s lives to maintain a sense of wellbeing. A
commonly overlooked dimension within this corpus of work concerns the dynamic nature of
people’s therapeutic place assemblages over time. This article provides these novel temporal
perspectives, drawing on the findings of an innovative three-stage interpretive geo-narrative
study conducted in south-west England from May to November 2013, designed to explore the
complex spatial-temporal ordering of people’s lives. Activity maps produced using
accelerometer and Global Positioning system (GPS) data were used to guide in-depth geonarrative
interviews with 33 participants, followed by a subset of go-along interviews in
therapeutic places deemed important by participants.
Concepts of “fleeting time”, “restorative time” and “biographical time” are used,
alongside notions of individual agency, to examine participants’ green and blue space
experiences in the context of the temporal structures characterising their everyday lives and
the biographical experiences contributing to the perceived importance of such settings over
time. In a culture that by and large prioritises speed, dominated by social ideals of, for
example, the “productive worker” and the “good parent”, participants conveyed a desire to
shift from “fleeting time” to “restorative time”, seeking a balance between embodied stillness and therapeutic mobility. This was deemed particularly important during more stressful life
transitions, such as parenthood, employment shifts and the onset of illness or impairment,
when participants worked hard to tailor their therapeutic geographies to shifting wellbeing
needs and priorities.This work was supported by the European Social Fund Convergence Programme for
Cornwall and the Isles of Scilly
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Geohydrology of Bandelier Tuff
The Los Alamos National Laboratory has been disposing of radioactive wastes since 1944. Environmental studies and monitoring for radioactive contamination started concurrently. In this report, only two mechanisms and rates by which the radionuclides can enter the environment are studied in detail: subsurface transport of radionuclides by migrating water, and diffusion of tritiated water (HTO) in the vapor phase. The report also includes a section concerning the influence of moisture on shear strength and possible resulting subsidences occurring in the pit overburdens. Because subsurface transport of radionuclides is influenced by the hydraulic conductivity and this in turn is regulated by the moisture content of any given material, a study was also undertaken involving precipitation, the most important climatic element influencing the geohydrology of any given area. Further work is in progress to correlate HTO emanation to atmospheric and pedological properties, especially including thermal characteristics of the tuff
Seeking everyday wellbeing: The coast as a therapeutic landscape
© 2015 Elsevier Ltd. All rights reservedPost-review pre-print. The version of record is available from the publisher via: doi:10.1016/j.socscimed.2015.08.011Recent research suggests coastal environments may promote human health and wellbeing. This article explores the diverse coastal experiences sought out by residents of two towns in south west England to promote and preserve their personal wellbeing in the context of their everyday lives. It draws on the findings of an in-depth interpretive study conducted from May to November 2013 that examined the relative contribution of varied green and blue space experiences to individual wellbeing through the life course. Personalised activity maps produced using accelerometer and Global Positioning System (GPS) data were used to guide in-depth geo-narrative interviews with a purposive sample of 33 participants. This was combined with a subset of nine case study go-along interviews in places deemed therapeutic by the participants themselves, offering deeper insight into the lived experiences and relationships playing out within such places. Situated in a novel adaptation of the therapeutic landscapes framework, this article explores how symbolic, achievement-oriented, immersive and social experiences contributed to participants' sense of wellbeing in their local coastal areas. Participants expressed particularly strong and often enduring connections to the local coastline, with different coastal stretches perceived to cater for varied therapeutic needs and interests, at multiple scales and intensities. The findings suggest the need for greater acknowledgement of people's emotional, deeply embodied and often shared connections to the coast within coastal management policy and practice, both nationally and internationally. Importantly, such efforts should recognise the fluid, dynamic nature of this land-sea boundary, and the valued therapeutic experiences linked to this fluidity.European Social Fund (ESF)European Regional Development Fun
Green space, health and wellbeing: Making space for individual agency
This is the author’s version of a work that was accepted for publication in Health and Place. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published at doi:10.1016/j.healthplace.2014.10.005.This essay examines the assumptions of green space use underpinning much existing green space and health research. It considers opportunities to move the field forward through exploring two often overlooked aspects of individual agency: the influence of shifting life circumstances on personal wellbeing priorities and place practices, and the role of personal orientations to nature in shaping how green space wellbeing opportunities are perceived and experienced. It suggests such efforts could provide more nuanced insights into the complex, personal factors that define and drive individual choices regarding the use of green spaces for wellbeing over time, thereby strengthening our understanding of the salutogenic potential (and limits) of green spaces.European Regional Development Fund Programme 2007 to 2013 and European Social Fund Convergence Programme for Cornwall and the Isles of Scilly
Using GPS and geo-narratives: A methodological approach for understanding and situating everyday green space encounters
This is the accepted version of the article, which has been published in final form at DOI: 10.1111/area.12152.This methods paper contributes to the recent proliferation of methodological innovation aimed at nurturing research encounters and exchanges that facilitate in-depth insights into people’s everyday practices and routine place encounters. By drawing on the experiences of an interpretive study seeking to situate people’s green space wellbeing practices within their daily lives, we suggest value in using personalised maps – produced using participant accelerometer (physical activity) and Global Positioning System (GPS) data – alongside in-depth and mobile ‘goalong’ qualitative interview approaches. After introducing the study and the methods adopted, the paper discusses three opportunities offered by this mixed method approach to contribute a more nuanced, contextualised understanding of participants’ green space experiences. These include: (a) the benefits of engaging participants in the interpretation of their own practices; (b) the value of using maps to provide a visual aid to discussion about the importance of participants’ routine, often pre-reflective practices; and (c) the production of a layered appreciation of participants’ local green and blue space wellbeing experiences. Used in combination, such methods have the potential to provide a more comprehensive picture of how current green space experiences, be they infrequent and meaningful, or more routine and habitual, are shaped by everyday individual agency, life circumstances and past place experiencesEuropean Social Fund Convergence Programme for Cornwall and the Isles of ScillyEuropean Regional Development Fund Programm
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