17 research outputs found

    Facilitating tree-ring dating of historic conifer timbers using Blue Intensity

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    The Scottish pine network expansion has been an ongoing task since 2006 and funding must be acknowledged to the following projects: EU project ‘Millennium’ (017008-2), Leverhulme Trust project ‘RELiC: Reconstructing 8000 years of Environmental and Landscape change in the Cairngorms (F/00268/BG)’, the Native Oak and Pine project or ‘NOAP’ (Historic Scotland) and the NERC project ‘SCOT2K:Reconstructing 2000 years of Scottish climate from tree rings (NE/K003097/1)’. Further PhD funding for Milos Rydval is acknowledged from The Carnegie Trust.Dendroarchaeology almost exclusively uses ring-width (RW) data for dating historical structures and artefacts. Such data can be used to date tree-ring sequences when regional climate dominates RW variability. However, the signal in RW data can be obscured due to site specific ecological influences (natural and anthropogenic) that impact crossdating success. In this paper, using data from Scotland, we introduce a novel tree-ring parameter (Blue Intensity – BI) and explore its utility for facilitating dendro historical dating of conifer samples. BI is similar to latewood density as they both reflect the combined hemicellulose, cellulose and lignin content in the latewood cell walls of conifer species and the amount of these compounds is strongly controlled, at least for trees growing in temperature limited locations, by late summer temperatures. BI not only expresses a strong climate signal, but is also less impacted by site specific ecological influences. It can be concurrently produced with RW data from images of finely sanded conifer samples but at a significantly reduced cost compared to traditional latewood density. Our study shows that the probability of successfully crossdating historical samples is greatly increased using BI compared to RW. Furthermore, due to the large spatial extent of the summer temperature signal expressed by such data, a sparse multi-species conifer network of long BI chronologies across Europe could be used to date and loosely provenance imported material.PostprintPeer reviewe

    Investigating post-stroke fatigue: An individual participant data meta-analysis

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    The prevalence of post-stroke fatigue differs widely across studies, and reasons for such divergence are unclear. We aimed to collate individual data on post-stroke fatigue from multiple studies to facilitate high-powered meta-analysis, thus increasing our understanding of this complex phenomenon.Methods: We conducted an Individual Participant Data (IPD) meta-analysis on post-stroke fatigue and its associated factors. The starting point was our 2016 systematic review and meta-analysis of post-stroke fatigue prevalence, which included 24 studies that used the Fatigue Severity Scale (FSS). Study authors were asked to provide anonymised raw data on the following pre-identified variables: (i) FSS score, (ii) age, (iii) sex, (iv) time post-stroke, (v) depressive symptoms, (vi) stroke severity, (vii) disability, and (viii) stroke type. Linear regression analyses with FSS total score as the dependent variable, clustered by study, were conducted.Results: We obtained data from 14 of the 24 studies, and 12 datasets were suitable for IPD meta-analysis (total n = 2102). Higher levels of fatigue were independently associated with female sex (coeff. = 2.13, 95% CI 0.44–3.82, p = 0.023), depressive symptoms (coeff. = 7.90, 95% CI 1.76–14.04, p = 0.021), longer time since stroke (coeff. = 10.38, 95% CI 4.35–16.41, p = 0.007) and greater disability (coeff. = 4.16, 95% CI 1.52–6.81, p = 0.010). While there was no linear association between fatigue and age, a cubic relationship was identified (p < 0.001), with fatigue peaks in mid-life and the oldest old.Conclusion: Use of IPD meta-analysis gave us the power to identify novel factors associated with fatigue, such as longer time since stroke, as well as a non-linear relationship with age

    Pregnancy and neonatal outcomes of COVID-19: The PAN-COVID study

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    Objective To assess perinatal outcomes for pregnancies affected by suspected or confirmed SARS-CoV-2 infection. Methods Prospective, web-based registry. Pregnant women were invited to participate if they had suspected or confirmed SARS-CoV-2 infection between 1st January 2020 and 31st March 2021 to assess the impact of infection on maternal and perinatal outcomes including miscarriage, stillbirth, fetal growth restriction, pre-term birth and transmission to the infant. Results Between April 2020 and March 2021, the study recruited 8239 participants who had suspected or confirmed SARs-CoV-2 infection episodes in pregnancy between January 2020 and March 2021. Maternal death affected 14/8197 (0.2%) participants, 176/8187 (2.2%) of participants required ventilatory support. Pre-eclampsia affected 389/8189 (4.8%) participants, eclampsia was reported in 40/ 8024 (0.5%) of all participants. Stillbirth affected 35/8187 (0.4 %) participants. In participants delivering within 2 weeks of delivery 21/2686 (0.8 %) were affected by stillbirth compared with 8/4596 (0.2 %) delivering ≥ 2 weeks after infection (95 % CI 0.3–1.0). SGA affected 744/7696 (9.3 %) of livebirths, FGR affected 360/8175 (4.4 %) of all pregnancies. Pre-term birth occurred in 922/8066 (11.5%), the majority of these were indicated pre-term births, 220/7987 (2.8%) participants experienced spontaneous pre-term births. Early neonatal deaths affected 11/8050 livebirths. Of all neonates, 80/7993 (1.0%) tested positive for SARS-CoV-2. Conclusions Infection was associated with indicated pre-term birth, most commonly for fetal compromise. The overall proportions of women affected by SGA and FGR were not higher than expected, however there was the proportion affected by stillbirth in participants delivering within 2 weeks of infection was significantly higher than those delivering ≥ 2 weeks after infection. We suggest that clinicians’ threshold for delivery should be low if there are concerns with fetal movements or fetal heart rate monitoring in the time around infection

    Dendrochronologically dated pine buildings from Scotland:the SCOT2K native pine dendrochronology project

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    The SCOT2K project has extended native pine tree-ring chronology coverage for Scotland to enable reconstruction of past climate and for cultural heritage dating benefits. Using living trees from multiple locations in the Highlands and sub-fossil material from lochs, a network of five regional chronologies has been produced. The project has developed the application of Blue Intensity (BI), a proxy measure for maximum latewood density, which is faster and less costly to obtain than traditional densitometry measurements. The use of both ring-width and BI has been demonstrated to greatly assist historical dendro-dating of pine. This paper presents the dating results for the twenty Scottish pine buildings or sites dendro-dated through the SCOT2K project. They range from the fifteenth to the nineteenth centuries, and from high-status castles to modest cruck cottages. They are mostly located in the Highlands where Scots pine occurs naturally, although an early example of long-distance transport is also identified.</p

    Dendrochronologically dated pine buildings from Scotland:the SCOT2K native pine dendrochronology project

    No full text
    The SCOT2K project has extended native pine tree-ring chronology coverage for Scotland to enable reconstruction of past climate and for cultural heritage dating benefits. Using living trees from multiple locations in the Highlands and sub-fossil material from lochs, a network of five regional chronologies has been produced. The project has developed the application of Blue Intensity (BI), a proxy measure for maximum latewood density, which is faster and less costly to obtain than traditional densitometry measurements. The use of both ring-width and BI has been demonstrated to greatly assist historical dendro-dating of pine. This paper presents the dating results for the twenty Scottish pine buildings or sites dendro-dated through the SCOT2K project. They range from the fifteenth to the nineteenth centuries, and from high-status castles to modest cruck cottages. They are mostly located in the Highlands where Scots pine occurs naturally, although an early example of long-distance transport is also identified.</p

    Incinération gallo-romaine à Lussat et fouilles de sauvetage en grande Limagne (Puy-de-Dôme) en 1976 / A romano-gaulish cremation burial at Lussat and rescue excavations in the Grande Limagne (Puy-de-Dôme) 1976.

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    Systematic observation and recording of drainage trenches in the Grande Limagne revealed evidence of occupation starting in the Neolithic, but especially from the later La Tène and Romano-Gaulish periods, when drainage trenches and ditched enclosures were being constructed. Unusual features at Lussat were an aqueduct made of imbrices, and a first century cremation burial. This latter, of a middle aged man produced a wide range of burnt pottery, cremated animal bones and cereals, and possibly furniture. Recent systematic field survey, excavation, and chance discoveries are materially altering our understanding of the occupation history of the Grande Limagne.La surveillance systématique des travaux de drainage et des terrassements liés à l'autoroute en Limagne a mis en évidence une occupation depuis le Néolithique et surtout durant la Tène et la période gallo-romaine. Les faits observés les plus significatifs demeurent l'aqueduc fait de tuiles creuses et l'incinération du Ier siècle mis au jour à Lussat. Celle-ci a produit une grande quantité de poteries brunes, de faune brûlée et de céréales. Cette surveillance, grâce aux découvertes qu'elle génère, permet de mieux cerner l'occupation du sol en Grande Limagne.Collis John, Hartley Brian R., Dickinson Brenda, Maltby Mark, Mills Coralie, Wells Calvin, Webley Derrick. Incinération gallo-romaine à Lussat et fouilles de sauvetage en grande Limagne (Puy-de-Dôme) en 1976 / A romano-gaulish cremation burial at Lussat and rescue excavations in the Grande Limagne (Puy-de-Dôme) 1976. . In: Revue archéologique du Centre de la France, tome 29, fascicule 1, 1990. pp. 5-17

    Facilitating tree-ring dating of historic conifer timbers using Blue Intensity

    No full text
    Dendroarchaeology almost exclusively uses ring-width (RW) data for dating historical structures and artefacts. Such data can be used to date tree-ring sequences when regional climate dominates RW variability. However, the signal in RW data can be obscured due to site specific ecological influences (natural and anthropogenic) that impact crossdating success. In this paper, using data from Scotland, we introduce a novel tree-ring parameter (Blue Intensity – BI) and explore its utility for facilitating dendro historical dating of conifer samples. BI is similar to latewood density as they both reflect the combined hemicellulose, cellulose and lignin content in the latewood cell walls of conifer species and the amount of these compounds is strongly controlled, at least for trees growing in temperature limited locations, by late summer temperatures. BI not only expresses a strong climate signal, but is also less impacted by site specific ecological influences. It can be concurrently produced with RW data from images of finely sanded conifer samples but at a significantly reduced cost compared to traditional latewood density. Our study shows that the probability of successfully crossdating historical samples is greatly increased using BI compared to RW. Furthermore, due to the large spatial extent of the summer temperature signal expressed by such data, a sparse multi-species conifer network of long BI chronologies across Europe could be used to date and loosely provenance imported material

    Harnessing global fisheries to tackle micronutrient deficiencies

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    Micronutrient deficiencies account for an estimated one million premature deaths annually, and for some nations can reduce gross domestic product(1,2) by up to 11%, highlighting the need for food policies that focus on improving nutrition rather than simply increasing the volume of food produced(3). People gain nutrients from a varied diet, although fish-which are a rich source of bioavailable micronutrients that are essential to human health(4)-are often overlooked. A lack of understanding of the nutrient composition of most fish(5) and how nutrient yields vary among fisheries has hindered the policy shifts that are needed to effectively harness the potential of fisheries for food and nutrition security(6). Here, using the concentration of 7 nutrients in more than 350 species of marine fish, we estimate how environmental and ecological traits predict nutrient content of marine finfish species. We use this predictive model to quantify the global spatial patterns of the concentrations of nutrients in marine fisheries and compare nutrient yields to the prevalence of micronutrient deficiencies in human populations. We find that species from tropical thermal regimes contain higher concentrations of calcium, iron and zinc; smaller species contain higher concentrations of calcium, iron and omega-3 fatty acids; and species from cold thermal regimes or those with a pelagic feeding pathway contain higher concentrations of omega-3 fatty acids. There is no relationship between nutrient concentrations and total fishery yield, highlighting that the nutrient quality of a fishery is determined by the species composition. For a number of countries in which nutrient intakes are inadequate, nutrients available in marine finfish catches exceed the dietary requirements for populations that live within 100 km of the coast, and a fraction of current landings could be particularly impactful for children under 5 years of age. Our analyses suggest that fish-based food strategies have the potential to substantially contribute to global food and nutrition security
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