717 research outputs found

    Neutrons from multiplicity-selected La-La and Nb-Nb collisions at 400A MeV and La-La collisions at 250A MeV

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    Triple-differential cross sections for neutrons from high-multiplicity La-La collisions at 250 and 400 MeV per nucleon and Nb-Nb collisions at 400 MeV per nucleon were measured at several polar angles as a function of the azimuthal angle with respect to the reaction plane of the collision. The reaction plane was determined by a transverse-velocity method with the capability of identifying charged-particles with Z=1, Z=2, and Z > 2. The flow of neutrons was extracted from the slope at mid-rapidity of the curve of the average in-plane momentum vs the center-of-mass rapidity. The squeeze-out of the participant neutrons was observed in a direction normal to the reaction plane in the normalized momentum coordinates in the center-of-mass system. Experimental results of the neutron squeeze-out were compared with BUU calculations. The polar-angle dependence of the maximum azimuthal anisotropy ratio r(θ)r(\theta) was found to be insensitive to the mass of the colliding nuclei and the beam energy. Comparison of the observed polar-angle dependence of the maximum azimuthal anisotropy ratio r(θ)r(\theta) with BUU calculations for free neutrons revealed that r(θ)r(\theta) is insensitive also to the incompressibility modulus in the nuclear equation of state.Comment: ReVTeX, 16 pages, 17 figures. To be published in Physical Review

    Mudflat surface morphology as a structuring agent of algae and associated macroepifauna communities: a case study in the Ria Formosa

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    Although mudflats seem relatively planar, closer inspection reveals a succession of meso-topographical features, including consecutive convex and concave meso- and micro-topographical features. The objective of this study was to determine the influence of meso-scale surface sediment morphology on the dynamics of the macroalgae Ulvales (Chlorophyta) and associated macroepifauna in the Ria Formosa tidal lagoon (southern coast of Portugal). Four sites in the Ria Formosa were sampled monthly. Two were located on convex sections (mounds) of the mudflat and the other two on concave sections (depressions). Macroalgae and related macroepifauna were sampled at each station. Biomass was quantified by determination of the ash-free dry weight (AFDW). Data were analysed using the software package ‘PRIMER’ (Plymouth Routines In Multivariate Ecological Research). Results show a clear distinction between convex and concave areas. In convex sections, Enteromorpha dominated, to the point of being the only algal species present during part of the year. Conversely, biomass and dynamics of Enteromorpha and Ulva were almost the same in concave sections. The associated macroepifauna was also different in protruding or depressed sections of the mudflat. In the convex areas, the macroepifauna population showed less diversity and was dominated by the snail Hydrobia ulvae. In concave areas, the species diversity was larger, but dominated in terms of biomass by the amphipod Melita palmata and the gastropod Nassarius pfeifferi. Results of the study indicate that the benthic communities associated with concave or convex features were different. No relevant differences in texture and sediment physico-chemical characteristics were found between convex and concave sections. The inference is that the morphological nature of the bottom in tidal mudflats can act as a structuring agent of benthic communities

    Flow analysis from multiparticle azimuthal correlations

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    We present a new method for analyzing directed and elliptic flow in heavy ion collisions. Unlike standard methods, it separates the contribution of flow to azimuthal correlations from contributions due to other effects. The separation relies on a cumulant expansion of multiparticle azimuthal correlations, and includes corrections for detector inefficiencies. This new method allows the measurement of the flow of identified particles in narrow phase-space regions, and can be used in every regime, from intermediate to ultrarelativistic energies.Comment: 31 pages, revtex. Published version (references added

    Barnyard grasses were processed with rice around 10000 years ago

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    Rice (Oryza sativa) is regarded as the only grass that was selected for cultivation and eventual domestication in the Yangtze basin of China. Although both macro-fossils and micro-fossils of rice have been recovered from the Early Neolithic site of Shangshan, dating to more than 10,000 years before present (BP), we report evidence of phytolith and starch microfossils taken from stone tools, both for grinding and cutting, and cultural layers, that indicating barnyard grass (Echinochloa spp.) was a major subsistence resource, alongside smaller quantities of acorn starches (Lithocarpus/Quercus sensu lato) and water chestnuts (Trapa). This evidence suggests that early managed wetland environments were initially harvested for multiple grain species including barnyard grasses as well as rice, and indicate that the emergence of rice as the favoured cultivated grass and ultimately the key domesticate of the Yangtze basin was a protracted process

    A zebrafish model of foxe3 deficiency demonstrates lens and eye defects with dysregulation of key genes involved in cataract formation in humans.

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    The Forkhead box E3 (FOXE3) gene encodes a transcription factor with a forkhead/winged helix domain that is critical for development of the lens and anterior segment of the eye. Monoallelic and biallelic deleterious sequence variants in FOXE3 cause aphakia, cataracts, sclerocornea and microphthalmia in humans. We used clustered regularly interspaced short palindromic repeats/Cas9 injections to target the foxe3 transcript in zebrafish in order to create an experimental model of loss of function for this gene. Larvae that were homozygous for an indel variant, c.296_300delTGCAG, predicting p.(Val99Alafs*2), demonstrated severe eye defects, including small or absent lenses and microphthalmia. The lenses of the homozygous foxe3 indel mutants showed more intense staining with zl-1 antibody compared to control lenses, consistent with increased lens fiber cell differentiation. Whole genome transcriptome analysis (RNA-Seq) on RNA isolated from wildtype larvae and larvae with eye defects that were putative homozygotes for the foxe3 indel variant found significant dysregulation of genes expressed in the lens and eye whose orthologues are associated with cataracts in human patients, including cryba2a, cryba1l1, mipa and hsf4. Comparative analysis of this RNA-seq data with iSyTE data identified several lens-enriched genes to be down-regulated in foxe3 indel mutants. We also noted upregulation of lgsn and crygmxl2 and downregulation of fmodb and cx43.4, genes that are expressed in the zebrafish lens, but that are not yet associated with an eye phenotype in humans. These findings demonstrate that this new zebrafish foxe3 mutant model is highly relevant to the study of the gene regulatory networks conserved in vertebrate lens and eye development

    The higher education impact agenda, scientific realism and policy change: the case of electoral integrity in Britain

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    Pressures have increasingly been put upon social scientists to prove their economic, cultural and social value through ‘impact agendas’ in higher education. There has been little conceptual and empirical discussion of the challenges involved in achieving impact and the dangers of evaluating it, however. This article argues that a critical realist approach to social science can help to identify some of these key challenges and the institutional incompatibilities between impact regimes and university research in free societies. These incompatibilities are brought out through an autobiographical ‘insider-account’ of trying to achieve impact in the field of electoral integrity in Britain. The article argues that there is a more complex relationship between research and the real world which means that the nature of knowledge might change as it becomes known by reflexive agents. Secondly, the researchers are joined into social relations with a variety of actors, including those who might be the object of study in their research. Researchers are often weakly positioned in these relations. Some forms of impact, such as achieving policy change, are therefore exceptionally difficult as they are dependent on other actors. Strategies for trying to achieve impact are drawn out such as collaborating with civil society groups and parliamentarians to lobby for policy change

    Participatory Visioning and Future Planning. Backcasting with Myanmar Farmers for a more Sustainable Future. Methodological Report

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    This report describes the methodology of participatory visioning and future planning, including a technique called backcasting. Based on literature and experience, we developed and applied this methodology to support smallholder farmers in southern Myanmar. In a highly participatory bottom-up approach, we co-created and documented the vision of these farmers – in direct collaboration with them – including their desirable futures, and we jointly explored possible pathways and action plans to reach these futures. We also co-implemented needs-based actions including concrete trainings, study trips, and a community-led micro-loan system to strengthen their agriculture – their main source of livelihood. Unfortunately, beginning in 2020, Myanmar experienced two overlapping waves of crisis: the health crisis as a result of the COVID-19 pandemic; and the political crisis following the coup d’etat in 2021. The final two years of the project were implemented under these extremely challenging conditions. We frequently had to adapt our operationalization to the very dynamic, changing circum-stances. Fortunately, our methodology allowed for this kind of adaptive management. Despite the challenging circumstances, the farmers were positive in their assessment of the project outcomes. This suggests that the methodology of participatory visioning and future planning can be effective even under difficult circumstances. We conclude the report by presenting lessons learnt and recommendations. Firstly, we reflect on how useful this methodology was and how it can be applied in similar or different projects (research, development, etc.). Secondly, we share our practical insights and recommendations regarding the application of the methodology in the given or similar contexts. Finally, we provide practical recommendations for project planning for those who want to include participatory visioning and future planning in their projects

    Political transition and emergent forest-conservation issues in Myanmar.

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    Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long-running civil war. With these transitions in mind, we used a horizon-scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land-tenure insecurity, large-scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure- and energy-project planning, and reforming land-tenure and environmental-protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions

    Sex‐related difference in the use of percutaneous left ventricular assist device in patients undergoing complex high‐risk percutaneous coronary intervention: Insight from the cVAD registry

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    ObjectiveTo assess the in‐hospital and short‐term outcome differences between males and females who underwent high‐risk PCI with mechanical circulatory support (MCS).BackgroundSex differences have been noted in several percutaneous coronary intervention (PCI) series with females less likely to be referred for PCI due increased risk of adverse events. However, data on sex differences in utilization and outcomes of high‐risk PCI with MCS is scarce.MethodsUsing the cVAD Registry, we identified 1,053 high‐risk patients who underwent PCI with MCS using Impella 2.5 or Impella CP. Patients with cardiogenic shock were excluded. A total of 792 (75.21%) males and 261 (24.79%) females were included in the analysis with median follow‐up of 81.5 days.ResultsFemales were more likely to be African American, older (72.05 ± 11.66 vs. 68.87 ± 11.17, p < .001), have a higher prevalence of diabetes (59.30 vs. 49.04%, p = .005), renal insufficiency (35.41 vs. 27.39%, p = .018), and peripheral vascular disease (31.89 vs. 25.39%, p of .05). Women had a higher mean STS score (8.21 ± 8.21 vs. 5.04 ± 5.97, p < .001) and lower cardiac output on presentation (3.64 ± 1.30 vs. 4.63 ± 1.49, p < .001). Although women had more comorbidities, there was no difference in in‐hospital mortality, stroke, MI or need for recurrent revascularization compared to males. Females were more likely to have multivessel revascularization than males. Ejection fraction improved in both males and females at the time of discharge (26.59 to 31.40% and 30.75 to 36.05%, respectively, p < .0001). However, females had higher rate of bleeding requiring transfusion compared with males (9.58 vs. 5.30%, p = .019).ConclusionFemale patients undergoing high PCI were older and had more comorbidities but had similar outcomes compared to males.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162726/2/ccd28509_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162726/1/ccd28509.pd
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