476 research outputs found

    Dynamics of precipitation pattern formation at geothermal hot springs

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    We formulate and model the dynamics of spatial patterns arising during the precipitation of calcium carbonate from a supersaturated shallow water flow. The model describes the formation of travertine deposits at geothermal hot springs and rimstone dams of calcite in caves. We find explicit solutions for travertine domes at low flow rates, identify the linear instabilities which generate dam and pond formation on sloped substrates, and present simulations of statistical landscape evolution

    Ancestral alleles and population origins: Inferences depend on mutation rate

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    Previous studies have found that at most human loci, ancestral alleles are African, in the sense that they reach their highest frequency there. Conventional wisdom holds that this reflects a recent African origin of modern humans. This paper challenges that view by showing that the empirical pattern (of elevated allele frequencies within Africa) is not as pervasive as has been thought. We confirm this African bias in a set of mainly protein-coding loci, but find a smaller bias in Alu insertion polymorphisms, and an even smaller bias in noncoding loci. Thus, the strong bias that was originally observed must reflect some factor that varies among data sets - something other than population history. This factor may be the per-locus mutation rate: the African bias is most pronounced in loci where this rate is high. The distribution of ancestral alleles among populations has been studied using 2 methods. One of these involves comparing the fractions of loci that reach maximal frequency in each population. The other compares the average frequencies of ancestral alleles. The first of these methods reflects history in a manner that depends on the mutation rate. When that rate is high, ancestral alleles at most loci reach their highest frequency in the ancestral population. When that rate is low, the reverse is true. The other method - comparing averages - is unresponsive. Average ancestral allele frequencies are affected neither by mutation rate nor by the history of population size and migration. In the absence of selection and ascertainment bias, they should be the same everywhere. This is true of one data set, but not of 2 others. This also suggests the action of some factor, such as selection or ascertainment bias, that varies among data sets. © The Author 2007. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved

    Understanding factors associated with the translation of cardiovascular research: A multinational case study approach

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    This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited.This article has been made available through the Brunel Open Access Publishing Fund.Background: Funders of health research increasingly seek to understand how best to allocate resources in order to achieve maximum value from their funding. We built an international consortium and developed a multinational case study approach to assess benefits arising from health research. We used that to facilitate analysis of factors in the production of research that might be associated with translating research findings into wider impacts, and the complexities involved. Methods: We built on the Payback Framework and expanded its application through conducting co-ordinated case studies on the payback from cardiovascular and stroke research in Australia, Canada and the United Kingdom. We selected a stratified random sample of projects from leading medical research funders. We devised a series of innovative steps to: minimize the effect of researcher bias; rate the level of impacts identified in the case studies; and interrogate case study narratives to identify factors that correlated with achieving high or low levels of impact. Results: Twenty-nine detailed case studies produced many and diverse impacts. Over the 15 to 20 years examined, basic biomedical research has a greater impact than clinical research in terms of academic impacts such as knowledge production and research capacity building. Clinical research has greater levels of wider impact on health policies, practice, and generating health gains. There was no correlation between knowledge production and wider impacts. We identified various factors associated with high impact. Interaction between researchers and practitioners and the public is associated with achieving high academic impact and translation into wider impacts, as is basic research conducted with a clinical focus. Strategic thinking by clinical researchers, in terms of thinking through pathways by which research could potentially be translated into practice, is associated with high wider impact. Finally, we identified the complexity of factors behind research translation that can arise in a single case. Conclusions: We can systematically assess research impacts and use the findings to promote translation. Research funders can justify funding research of diverse types, but they should not assume academic impacts are proxies for wider impacts. They should encourage researchers to consider pathways towards impact and engage potential research users in research processes. © 2014 Wooding et al.; licensee BioMed Central Ltd.RAND Europe and HERG, with subsequent funding from the NHFA, the HSFC and the CIHR. This research was also partially supported by the Policy Research Programme in the English Department of Health

    Comparing research investment to United Kingdom institutions and published outputs for tuberculosis, HIV and malaria: A systematic analysis across 1997-2013

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    Background: The "Unfinished Agenda" of infectious diseases is of great importance to policymakers and research funding agencies that require ongoing research evidence on their effective management. Journal publications help effectively share and disseminate research results to inform policy and practice. We assess research investments to United Kingdom institutions in HIV, tuberculosis and malaria, and analyse these by numbers of publications and citations and by disease and type of science. Methods: Information on infection-related research investments awarded to United Kingdom institutions across 1997-2010 were sourced from funding agencies and individually categorised by disease and type of science. Publications were sourced from the Scopus database via keyword searches and filtered to include only publications relating to human disease and containing a United Kingdom-based first and/or last author. Data were matched by disease and type of science categories. Investment (United Kingdom pounds) and publications were compared to generate an 'investment per publication' metric; similarly, an 'investment per citation' metric was also developed as a measure of the usefulness of research. Results: Total research investment for all three diseases was £1.4 billion, and was greatest for HIV (£651.4 million), followed by malaria (£518.7 million) and tuberculosis (£239.1 million). There were 17,271 included publications, with 9,322 for HIV, 4,451 for malaria, and 3,498 for tuberculosis. HIV publications received the most citations (254,949), followed by malaria (148,559) and tuberculosis (100,244). According to UK pound per publication, tuberculosis (£50,691) appeared the most productive for investment, compared to HIV (£61,971) and malaria (£94,483). By type of science, public health research was most productive for HIV (£27,296) and tuberculosis (£22,273), while phase I-III trials were most productive for malaria (£60,491). According to UK pound per citation, tuberculosis (£1,797) was the most productive area for investment, compared to HIV (£2,265) and malaria (£2,834). Public health research was the most productive type of science for HIV (£2,265) and tuberculosis (£1,797), whereas phase I-III trials were most productive for malaria (£1,713). Conclusions: When comparing total publications and citations with research investment to United Kingdom institutions, tuberculosis research appears to perform best in terms of efficiency. There were more public health-related publications and citations for HIV and tuberculosis than other types of science. These findings demonstrate the diversity of research funding and outputs, and provide new evidence to inform research investment strategies for policymakers, funders, academic institutions, and healthcare organizations.Infectious Disease Research Networ

    Measuring research impact: a large cancer research funding programme in Australia

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    Background: Measuring research impact is of critical interest to philanthropic and government funding agencies interested in ensuring that the research they fund is both scientifically excellent and has meaningful impact into health and other outcomes. The Beat Cancer Project (BCP) is a AUD 34mcancerresearchfundingschemethatcommencedin2011.ItwasinitiatedbyanAustraliancharity(CancerCouncilSA),andsupportedbytheSouthAustralianGovernmentandthestate’smajoruniversities.Methods:ThisstudyappliedBuxtonandHanney’sPaybackFrameworktoassessresearchimpactgeneratedfromtheBCPafter3yearsoffunding.Datasourceswereanauditofpeer−reviewedpublicationsfromJanuary2011toSeptember2014fromWebofKnowledgeandaself−reportsurveyofinvestigatorsawardedBCPresearchfundingduringitsfirst3yearsofimplementation(2011–2013).Ofthe104surveys,92(88Results:TheBCPperformedwellacrossallfivecategoriesofthePaybackFramework.Intermsofknowledgeproduction,1257peer−reviewedpublicationsweregeneratedandthemeanimpactfactorofpublishingjournalsincreasedannually.Thereweremanybenefitstofutureresearchwith21respondents(2334 m cancer research funding scheme that commenced in 2011. It was initiated by an Australian charity (Cancer Council SA), and supported by the South Australian Government and the state’s major universities. Methods: This study applied Buxton and Hanney’s Payback Framework to assess research impact generated from the BCP after 3 years of funding. Data sources were an audit of peer-reviewed publications from January 2011 to September 2014 from Web of Knowledge and a self-report survey of investigators awarded BCP research funding during its first 3 years of implementation (2011–2013). Of the 104 surveys, 92 (88%) were completed. Results: The BCP performed well across all five categories of the Payback Framework. In terms of knowledge production, 1257 peer-reviewed publications were generated and the mean impact factor of publishing journals increased annually. There were many benefits to future research with 21 respondents (23%) reporting career advancement, and 110 higher degrees obtained or expected (including 84 PhDs). Overall, 52% of funded projects generated tools for future research. The funded research attracted substantial further income yielding a very high rate of leverage. For every AUD 1 that the cancer charity invested, the BCP gained an additional AUD $6.06. Five projects (5%) had informed policy and 5 (5%) informed product development, with an additional 31 (34%) and 35 (38%) projects, respectively, anticipating doing so. In terms of health and sector and broader economic benefits, 8 (9%) projects had influenced practice or behaviour of health staff and 32 (34%) would reportedly to do so in the future. Conclusions: Research impact was a priority of charity and government funders and led to a deliberate funding strategy. Emphasising research impact while maintaining rigorous, competitive processes can achieve the joint objectives of excellence in research, yielding good research impact and a high rate of leverage for philanthropic and public investment, as indicated by these early results

    An African-specific haplotype in MRGPRX4 is associated with menthol cigarette smoking

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    In the U.S., more than 80% of African-American smokers use mentholated cigarettes, compared to less than 30% of Caucasian smokers. The reasons for these differences are not well understood. To determine if genetic variation contributes to mentholated cigarette smoking, we performed an exome-wide association analysis in a multiethnic population-based sample from Dallas, TX (N = 561). Findings were replicated in an independent cohort of African Americans from Washington, DC (N = 741). We identified a haplotype of MRGPRX4 (composed of rs7102322[G], encoding N245S, and rs61733596[G], T43T), that was associated with a 5-to-8 fold increase in the odds of menthol cigarette smoking. The variants are present solely in persons of African ancestry. Functional studies indicated that the variant G protein-coupled receptor encoded by MRGPRX4 displays reduced agonism in both arrestin-based and G protein-based assays, and alteration of agonism by menthol. These data indicate that genetic variation in MRGPRX4 contributes to inter-individual and inter-ethnic differences in the preference for mentholated cigarettes, and that the existence of genetic factors predisposing vulnerable populations to mentholated cigarette smoking can inform tobacco control and public health policies

    Digitally Enlightened or Still in the Dark? Establishing a Sector-Wide Approach to Enhancing Data Synthesis and Research Potential in British Environmental Archaeology and Beyond

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    In a 2019 Internet Archaeology article, Elizabeth Pearson posed the question 'are we back in the Dark Ages?'. This question was made in reference to a developer-funded archaeology sector that was generating vast quantities of evidence and, particularly, in recent years, specialist environmental data, but was failing to mobilise this in a theoretical framework that generated meaningful advancement in terms of research. The introduction to the 2021 Internet Archaeology special issue on Digital Archiving in Archaeology (Richards et al. 2021) went on to address 'a digital resource that is now in jeopardy' – not only because of the risk of technical obsolescence, but also because of crucial limitations to its interoperability and discoverability. This article builds on these arguments and complements vital work underway on high-level, internationally focused data infrastructure initiatives (e.g. Wright and Richards 2018). We emphasise here the importance of parallel discussions at a community level, particularly with the people who routinely produce archaeological data, as key to enhancing data synthesis and research potential. Specifically, we report on two surveys conducted by the 'Rewilding' Later Prehistory project at Oxford Archaeology, in collaboration with Historic England and Bournemouth University, which originated in the 'Rewilding' project's concern with improving access to palaeoenvironmental data produced within Britain. Substantial amounts of zooarchaeological and archaeobotanical data remain buried in grey literature, limited-access publications and archive reports (not to mention floppy disks, CDs and microfiche), with no integrative means of searching for particular periods or categories of evidence. This lack of accessibility inhibits specialists from contextualising their findings, and was exemplified recently by the Archaeology on Furlough project tripling the known number of aurochs finds in Britain by trawling online records, journals and museum records (Wiseman 2020). The results of the surveys presented here, which targeted both environmental archaeologists specifically and the wider sector, demonstrate a significant appetite amongst archaeologists to improve data networks and for their work to contribute meaningfully to research agendas. Contextualised within a disciplinary landscape that is increasingly dynamic in its approach to tackling the openness and connectivity of 'big data', we argue that better data synthesis in environmental archaeology, and the developer-funded sector more broadly, can be more than just a mirage on the horizon, particularly once the people who produce the data are given an active voice in the matter

    Developmental Expression and Glucocorticoid Control of the Leptin Receptor in Fetal Ovine Lung.

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    The effects of endogenous and synthetic glucocorticoids on fetal lung maturation are well-established, although the role of leptin in lung development before birth is unclear. This study examined mRNA and protein levels of the signalling long-form leptin receptor (Ob-Rb) in fetal ovine lungs towards term, and after experimental manipulation of glucocorticoid levels in utero by fetal cortisol infusion or maternal dexamethasone treatment. In fetal ovine lungs, Ob-Rb protein was localised to bronchiolar epithelium, bronchial cartilage, vascular endothelium, alveolar macrophages and type II pneumocytes. Pulmonary Ob-Rb mRNA abundance increased between 100 (0.69 fractional gestational age) and 144 days (0.99) of gestation, and by 2-4-fold in response to fetal cortisol infusion and maternal dexamethasone treatment. In contrast, pulmonary Ob-Rb protein levels decreased near term and were halved by glucocorticoid treatment, without any significant change in phosphorylated signal transducer and activator of transcription-3 (pSTAT3) at Ser727, total STAT3 or the pulmonary pSTAT3:STAT3 ratio. Leptin mRNA was undetectable in fetal ovine lungs at the gestational ages studied. These findings demonstrate differential control of pulmonary Ob-Rb transcript abundance and protein translation, and/or post-translational processing, by glucocorticoids in utero. Localisation of Ob-Rb in the fetal ovine lungs, including alveolar type II pneumocytes, suggests a role for leptin signalling in the control of lung growth and maturation before birth.This work was supported by the Biotechnology and Biological Sciences Research Council (grant numbers S18103 and BB/H01697X/1).This is the final version of the article. It first appeared from PLoS via http://dx.doi.org/10.1371/journal.pone.013611
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