434 research outputs found

    Normal background concentrations (NBCs) of contaminants in English soils : final project report

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    The British Geological Survey (BGS) has been commissioned by the Department for Environment, Food and Rural Affairs (Defra) to give guidance on what are normal levels of contaminants in English soils in support of the Part 2A Contaminated Land Statutory Guidance. This has initially been done by studying the distribution of four contaminants – arsenic, lead, benzo[a]pyrene (BaP) and asbestos – in topsoils from England. This work was extended to a further four contaminants (cadmium, copper, nickel and mercury) which enabled methodologies developed to be tested on a larger range of contaminants. The first phase of the Project gathered data sets that were: nationally extensive; systematically collected so a broad range of land uses were represented; and collected and analysed to demonstrably and acceptable levels of quality. Information on the soil contaminant concentrations in urban areas was of particular importance as the normal background is considered to be a combination of both natural and diffuse anthropogenic contributions to the soil. Issues of soil quality are most important in areas where these affect most people, namely, the urban environment. The two principal data sets used in this work are the BGS Geochemical Baseline Survey of the Environment (G-BASE) rural and urban topsoils (37,269 samples) and the English NSI (National Soil Inventory) topsoils (4,864 samples) reanalysed at the BGS laboratories by X-ray fluorescence spectrometry (XRFS) so both data sets were highly compatible. These two data sets provide results for most inorganic element contaminants, though results explored for mercury and BaP are drawn from a variety of different and much less extensive data sets

    Changes in reproductive morphology and physiology observed in the amphipod crustacean, Melita nitida Smith, maintained in the laboratory on polluted estuarine sediments

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    An earlier study showed that the amphipod crustacean Melita nitida Smith maintained on sediments dosed with waste crankcase oil developed physiological and morphological abnormalities. Most notably, mature females developed abnormal setae along the edges of their brood plates. The present study was conducted to determine whether similar abnormalities might be induced in animals maintained on polluted field sediments containing petroleum by-products among other toxic substances. In the laboratory, heterosexual pairs were maintained on three sediments taken from Jamaica Bay (New York) plus one control sediment and one toxic substratum (Ulva lactuca (L.) thalli). The results mirrored the results of the previous study. Under controlled conditions brood production was reduced on polluted sediments by as much as 57% and a greater proportion of females maintained on polluted sediments developed abnormal brood plate setae. In contrast, while brood production was lower in females exposed to U. lactuca than on the control sediment, there was no significant difference between the two groups in the number of females that developed abnormal brood plates

    HOLISDER Project: Introducing Residential and Tertiary Energy Consumers as Active Players in Energy Markets

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    Although it has been demonstrated that demand-side flexibility is possible, business application of residential and small tertiary demand response programs has been slow to develop. This paper presents a holistic demand response optimization framework that enables significant energy costs reduction for consumers. Moreover, buildings are introduced as main contributors to balance energy networks. The solution basis consists of a modular interoperability and data management framework that enables open standards-based communication along the demand response value chain. The solution is being validated in four large-scale pilot sites, which have diverse building types, energy systems and energy carriers. Furthermore, they offer diverse climatic conditions, and demographic and cultural characteristics to establish representative results.Research leading to these results has been supported by HOLISDER project. This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No. 768614. The APC was funded by HOLISDER project

    An efficient algorithm for computing the Baker-Campbell-Hausdorff series and some of its applications

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    We provide a new algorithm for generating the Baker--Campbell--Hausdorff (BCH) series Z = \log(\e^X \e^Y) in an arbitrary generalized Hall basis of the free Lie algebra L(X,Y)\mathcal{L}(X,Y) generated by XX and YY. It is based on the close relationship of L(X,Y)\mathcal{L}(X,Y) with a Lie algebraic structure of labeled rooted trees. With this algorithm, the computation of the BCH series up to degree 20 (111013 independent elements in L(X,Y)\mathcal{L}(X,Y)) takes less than 15 minutes on a personal computer and requires 1.5 GBytes of memory. We also address the issue of the convergence of the series, providing an optimal convergence domain when XX and YY are real or complex matrices.Comment: 30 page

    Iodine source apportionment in the Malawian diet

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    The aim of this study was to characterise nutritional-I status in Malawi. Dietary-I intakes were assessed using new datasets of crop, fish, salt and water-I concentrations, while I status was assessed for 60 women living on each of calcareous and non-calcareous soils as defined by urinary iodine concentration (UIC). Iodine concentration in staple foods was low, with median concentrations of 0.01 mg kg−1 in maize grain, 0.008 mg kg−1 in roots and tubers, but 0.155 mg kg−1 in leafy vegetables. Freshwater fish is a good source of dietary-I with a median concentration of 0.51 mg kg−1. Mean Malawian dietary-Iodine intake from food, excluding salt, was just 7.8 ÎŒg d−1 compared to an adult requirement of 150 ÎŒg d−1. Despite low dietary-I intake from food, median UICs were 203 ÎŒg L−1 with only 12% defined as I deficient whilst 21% exhibited excessive I intake. Iodised salt is likely to be the main source of dietary I intake in Malawi; thus, I nutrition mainly depends on the usage and concentration of I in iodised salt. Drinking water could be a significant source of I in some areas, providing up to 108 ÎŒg d−1 based on consumption of 2 L d−1

    Efficacy of edelfosine lipid nanoparticles in breast cancer cells

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    Breast cancer is a heterogeneous group of neoplasms predominantly originating in the terminal duct lobular units. It represents the leading cause of cancer death in women and the survival frequencies for patients at advanced stages of the disease remain low. New treatment options need to be researched to improve these rates. The anti-tumor ether lipid edelfosine (ET) is the prototype of a novel generation of promising anticancer drugs. However, it presents several drawbacks for its use in cancer therapy, including gastrointestinal and hemolytic toxicity and low oral bioavailability. To overcome these obstacles, ET was encapsulated in Precirol ATO 5 lipid nanoparticles (ET-LN), and its anti-tumor potential was in vitro tested in breast cancer. The formulated ET-LN were more effective in inhibiting cell proliferation and notably decreased cell viability, showing that the cytotoxic effect of ET was considerably enhanced when ET was encapsulated. In addition, ET and ET-LN were able to promote cell cycle arrest at G1 phase. Moreover, although both treatments provoked an apoptotic effect in a time-dependent manner, such anti-tumor effects were noticeably improved with ET-LN treatment. Therefore, our results indicate that encapsulating ET in LN played an essential role in improving the efficacy of the drug

    Human Placental Syncytiotrophoblasts Restrict Toxoplasma gondii Attachment and Replication and Respond to Infection by Producing Immunomodulatory Chemokines

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    Toxoplasma gondii is a major source of congenital disease worldwide, but the cellular and molecular factors associated with its vertical transmission are largely unknown. In humans, the placenta forms the key interface between the maternal and fetal compartments and forms the primary barrier that restricts the hematogenous spread of microorganisms. Here, we utilized primary human trophoblast (PHT) cells isolated from full-term placentas and human midgestation chorionic villous explants to determine the mechanisms by which human trophoblasts restrict and respond to T. gondii infection. We show that placental syncytiotrophoblasts, multinucleated cells that are in direct contact with maternal blood, restrict T. gondii infection at two distinct stages of the parasite lytic cycle—at the time of attachment and also during intracellular replication. Utilizing comparative transcriptome sequencing (RNA-seq) transcriptional profiling, we also show that human placental trophoblasts from both the second and third trimesters respond uniquely to T. gondii infection compared to trophoblast cell lines, typified by the upregulation of several immunity-related genes. One of the most differentially induced genes was the chemokine CCL22, which relies on the secretion of a parasite effector(s) either during or after invasion for its induction. Collectively, our findings provide new insights into the mechanisms by which the human placenta restricts the vertical transmission of T. gondii at early and late stages of human pregnancy and demonstrate the existence of at least two interferon-independent pathways that restrict T. gondii access to the fetal compartment. IMPORTANCE Toxoplasma gondii is a major source of congenital disease worldwide and must breach the placental barrier to be transmitted from maternal blood to the developing fetus. The events associated with the vertical transmission of T. gondii are largely unknown. Here, we show that primary human syncytiotrophoblasts, the fetus-derived cells that comprise the primary placental barrier, restrict T. gondii infection at two distinct stages of the parasite life cycle and respond to infection by inducing a unique immunomodulatory transcriptional profile. Collectively, our findings provide important insights into the mechanisms by which human syncytiotrophoblasts restrict T. gondii infection at early and late stages of human pregnancy, identify both permissive and resistant human placental cell types, and identify the placenta-enriched signaling pathways induced in response to infection

    Determination of stream sediment background concentrations in mineralised catchments impacted by mining using Tellus data from Northern Ireland : final project report

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    Background metal(loids) concentrations, intended as concentrations of naturally occurring substances rather than anthropogenic, are more often integrated in the assessment of water and sediment quality. This approach allows that ecosystems may be adapted or acclimatised to certain concentrations of metals in surface water and sediments as a result of their natural abundance. Background values of metal(loids) have long been recognised to be higher in mineralised catchments than those in unmineralised, and this is in fact the same as the central precept of geochemical exploration for economic ore deposits. From the environmental perspective, these mineralised zones should be considered as a separate baseline unit from that of the unmineralised formation. Information on the baseline conditions of catchments prior to mining is needed to better understand what restoration goals are achievable in mining impacted catchments. The geochemical baseline data also provide a reference point against which changes can be measured and can be used both by industry and regulators in future mine applications. In this project an approach for deriving pre-mining baseline sediment concentrations using systematically collected survey geochemical data is demonstrated using the mineralised area associated with the Ordovician-Silurian rocks in southern Co. Armagh in Northern Ireland as study area. The Tellus geochemical survey data for sediments were used for this scope. International literature has usefully provided methodologies and examples of deriving ‘background’ concentrations in mineralised catchments. Statistical methods in use to distinguish between anomalous and background concentrations in geochemical exploration of mineral deposits all converge on various methods of discriminating outliers and making estimates of central tendency, spread and identification of upper thresholds of background. The statistical method used in this project is the method of Sinclair (1976a) and applied using the ‘PROBPLOT’ code (Stanley, 1987), reproduced in an ‘R’ script environment. This method chooses threshold values between anomalous and background geochemical data, based on partitioning a cumulative probability plot of the data. Data analysis has primarily focused on elements for which there are sediment quality standards derived in other jurisdictions, which may be adopted in the UK regulatory framework in future. Probability distribution plots of stream sediment lead (Pb) zinc (Zn), arsenic (As), chromium (Cr) and nickel (Ni) concentrations have been partitioned in the respective contributing populations and population statistics derived (mean and standard deviation). Interpretation of the significance of the resulting groupings of data and understanding different background populations has then been achieved through analysis of the spatial distribution of the groups in a GIS framework. Where data exceed environmental quality standards, these populations can assist in identifying where natural background concentrations (due to mineralogical variations in the catchment geology) may contribute to the exceedance. This is designed to aid the decision-making process in relation to why quality standards may have failed, or if there is any merit in ‘remediation’ of a natural ecosystem. Separation of the more widespread, potentially natural, high concentrations from the data populations which reflect very high concentrations (more likely to arise from anthropogenic sources) could also help in targeting key sites for further investigation

    A hierarchical Bayesian model for estimating age-specific COVID-19 infection fatality rates in developing countries

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    The COVID-19 infection fatality rate (IFR) is the proportion of individuals infected with SARS-CoV-2 who subsequently die. As COVID-19 disproportionately affects older individuals, age-specific IFR estimates are imperative to facilitate comparisons of the impact of COVID-19 between locations and prioritize distribution of scare resources. However, there lacks a coherent method to synthesize available data to create estimates of IFR and seroprevalence that vary continuously with age and adequately reflect uncertainties inherent in the underlying data. In this paper we introduce a novel Bayesian hierarchical model to estimate IFR as a continuous function of age that acknowledges heterogeneity in population age structure across locations and accounts for uncertainty in the estimates due to seroprevalence sampling variability and the imperfect serology test assays. Our approach simultaneously models test assay characteristic, serology, and death data, where the serology and death data are often available only for binned age groups. Information is shared across locations through hierarchical modeling to improve estimation of the parameters with limited data. Modeling data from 26 developing country locations during the first year of the COVID-19 pandemic, we found seroprevalence did not change dramatically with age, and the IFR at age 60 was above the high-income country benchmark for most locations

    A reconnaissance survey of farmers’ awareness of hypomagnesaemic tetany in UK cattle and sheep farms

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    Hypomagnesaemic tetany (HypoMgT) in ruminants is a physiological disorder caused by inadequate intake or impaired absorption of magnesium (Mg) in the gut. If it is not detected and treated in time, HypoMgT can cause the death of the affected animal. A semi-structured questionnaire survey was conducted from July 2016–2017 to assess farmers’ awareness of HypoMgT in cattle and sheep in the UK. The questionnaire was distributed to farmers at farm business events and agricultural shows, and through a collaborative group of independent veterinary practices to their clients. Farmers were asked about (i) the incidence of presumed HypoMgT (PHT); (ii) their strategies to treat or prevent HypoMgT; (iii) mineral tests on animals, forage and soil, and (iv) farm enterprise type. A total of 285 responses were received from 82 cattle, 157 mixed cattle and sheep, and 46 sheep farmers, of whom 39% reported HypoMgT in their livestock, affecting 1–30 animals. Treatment and/or prevention against HypoMgT was reported by 96% respondents with PHT and 79% of those without. Mineral tests on animal, forage, and soil was conducted by 24%, 53%, and 66% of the respondents, respectively, regardless of PHT. There was a highly significant association between the use of interventions to tackle HypoMgT and the incidence of PHT (p < 0.01). The top three treatment/prevention strategies used were reported as being free access supplementation (149), in feed supplementation (59) and direct to animal treatments (drenches, boluses and injections) (45) although these did vary by farm type. Although some (9) reported using Mg-lime, no other pasture management interventions were reported (e.g., Mg-fertilisation or sward composition). Generally, the results indicate that UK farmers are aware of the risks of HypoMgT. A more integrated soil-forage-animal assessment may improve the effectiveness of tackling HypoMgT and help highlight the root causes of the problem
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