4,122 research outputs found

    The Role of Secreted Frizzled Related Protein 4 (sFRP-4) in Regulating Oestradiol-Induced Growth of the MCF-7 Breast Cancer Cell Line

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    The Wnt signalling pathway is involved in regulating cellular proliferation and differentiation, and aberrant activation has been described in several cancers including breast. Oestradiol up regulates Wnt pathway gene expression, and thereby activates the Wnt signalling pathway. We used the oestrogen-responsive breast cancer cell line MCF-7 to examine the effects of secreted frizzled related protein 4 (sFRP-4) on oestradiol-induced growth, including gene expression of the Wnt signalling pathway genes Frizzled Receptor, Wnt-10b, and β-catenin. We demonstrate here that sFRP-4 inhibits oestradiol-induced cell growth in the MCF-7 cell line and also down regulates oestradiol-induced expression of selected Wnt signalling genes including β-catenin. We propose that sFRP-4 is a potent inhibitor of the Wnt signalling pathway and may negatively regulate oestradiol-mediated proliferation in human breast cancer cells

    Structure and implementation of novel task rules: A cross-sectional developmental study

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    This is the author accepted manuscript. The final version is available from SAGE Publications via the DOI in this record.Rule-based performance improves remarkably throughout childhood. The present study examined how children and adolescents structured tasks and implemented rules when novel task instructions were presented in a child-friendly version of a novel instruction-learning paradigm. Each mini-block started with the presentation of the new stimulus-response mappings for a GO task. Prior to implementing this mapping, responses were required to advance through screens during a preparatory (NEXT) phase. Children (4-11 years) and late adolescents (17-19 years) responded more slowly during the NEXT phase when the NEXT response was incompatible with the instructed stimulus-response mapping. This instructionbased interference effect was more pronounced in young children than in older children. We argue that these findings are most consistent with age-related differences in rule structuring. We discuss the implications of our findings for theories of rule-based performance, instruction-based learning, and development.This work was supported by an ERC starting grant to FV (No. 312445)

    Fractionation of arsenic in soil by a continuous-flow sequential extraction method

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    Batch sequential extraction techniques for fractionating metals or metalloids in soils are time consuming and subject to several potential errors. The development of a continuous-flow sequential extraction method for soil As is described and assessed, having the benefits of simplicity, rapidity, less risk of contamination, and less vulnerability to changes in extraction conditions compared with traditional batch methods. The validated method was used to fractionate soil As using water, NaHCO₃, NaOH, and HCl, followed by digestion of the residue with HNO₃, and HF acids. The extracts and digests were analyzed for As by graphite furnace atomic absorption spectrometry. Good recoveries of total soil As (97–115%) were obtained and fractionation data generally comparable with those obtained using conventional batch techniques. Soils from a tin-mining area in Thailand and soils from As-contaminated cattle (Bos taurus) dip sites in Australia were used to test the applicability of the method, and to demonstrate the usefulness of the extractogram obtained. The ability to produce detailed extractograms for As and other elements (Al, Fe, and Ca) enabled an examination of elemental associations in individual fractions. With the exception of As extracted with HCl, the extractograms generally support previous suggestions of the likely forms or associations of As present in the different soil fractions

    Low‐temperature crystallization of La0.15Sr0.775TiO3 using ionic liquids

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    The n‐type thermoelectric oxide La0.15Sr0.775TiO3 (LST) has been synthesized at 600°C using an ionic liquid method. The method uses the ionic liquid 1‐ethyl 3‐methylimidazolium acetate as the sole complexing agent: the lack of a second, carbon‐rich template decreases the quantity of reduced intermediate phases which form during heating. By suppressing these phases, greatly reduced temperatures can be used to crystallize the perovskite LST phase, on the nanoscale. These nanoparticles have the potential to be used to increase the figure of merit in n‐type thermoelectric oxide devices

    Book Reviews

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    Uncharted waters: the unintended impacts of residual chlorine on water quality and biofilms

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    Disinfection residuals in drinking water protect water quality and public heath by limiting planktonic microbial regrowth during distribution. However, we do not consider the consequences and selective pressures of such residuals on the ubiquitous biofilms that persist on the vast internal surface area of drinking water distribution systems. Using a full scale experimental facility, integrated analyses were applied to determine the physical, chemical and biological impacts of different free chlorine regimes on biofilm characteristics (composition, structure and microbiome) and water quality. Unexpectedly, higher free chlorine concentrations resulted in greater water quality degredation, observable as elevated inorganic loading and greater discolouration (a major cause of water quality complaints and a mask for other failures). High-chlorine concentrations also reduced biofilm cell concentrations but selected for a distinct biofilm bacterial community and inorganic composition, presenting unique risks. The results challenge the assumption that a measurable free chlorine residual necessarily assures drinking water safety

    Social science sequestered

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    Greenhouse gas removal (GGR) raises many cultural, ethical, legal, social, and political issues, yet in the growing area of GGR research, humanities and social sciences (HASS) research is often marginalized, constrained and depoliticised. This global dynamic is illustrated by an analysis of the UK GGR research programme. This dynamic matters for the knowledge produced and for its users. Without HASS contributions, too narrow a range of perspectives, futures and issues will be considered, undermining or overpromising the prospects for the responsible development of GGR (and threatening worse side-effects), and limiting our understanding of why and how policy demands GGR solutions in the first place. In response, we present policy principles for bringing HASS fully into GGR research, organized around three themes: (1) HASS-led GGR research, (2) Opening up GGR futures, and (3) The politics of GGR futures.We acknowledge funding from the UK GGR programme, under several specific grants: NE/P019838/1, NE/P019900/1, NE/P019951/1, NE/P019668/1, and NE/P01982X/1

    Alien invasions and livelihoods: Economic benefits of invasive Australian Red Claw crayfish in Jamaica

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    Invasive species have caused widespread economic and environmental disruption, which have been widely studied. However, their potential benefits have received much less attention. If invasive species contribute to livelihoods, their eradication may negatively impact wellbeing. Failing to value these benefits may lead to an undervaluation of invaded ecosystems. We assess the potential economic benefits of an invasive species within an artisanal fishery in Jamaica. We monitored catches over 259 fisherman-days, and conducted 45 semi-structured interviews, with 76 fishermen. We show that the invasive Australian Red Claw crayfish (Cherax quadricarinatus) is an important source of income for fishermen within the Black River Lower Morass of Jamaica and supplement incomes during periods when native shrimp (Macrobrachium spp.) catches decline. We also show that full-time fishermen and those who have no alternative occupations expend the greatest fishing effort. We use the intra-annual variation of fishermen's harvest effort between seasons (when catch per unit effort changes) as a proxy for dependence. Using this measure, we found that the least wealthy appear to be the most dependent on fishing, and consequently benefit the most from the invasive crayfish. Our results demonstrate the importance of considering the potential benefits of invasive species within integrated landscape management
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