553 research outputs found

    Using scenarios to explore UK upland futures

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    Uplands around the world are facing significant social, economic and environmental changes, and decision-makers need to better understand what the future may hold if they are to adapt and maintain upland goods and services. This paper draws together all major research comprising eight studies that have used scenarios to describe possible futures for UK uplands. The paper evaluates which scenarios are perceived by stakeholders to be most likely and desirable, and assesses the benefits and drawbacks of the scenario methods used in UK uplands to date. Stakeholders agreed that the most desirable and likely scenario would be a continuation of hill farming (albeit at reduced levels) based on cross-compliance with environmental measures. The least desirable scenario is a withdrawal of government financial support for hill farming. Although this was deemed by stakeholders to be the least likely scenario, the loss of government support warrants close attention due to its potential implications for the local economy. Stakeholders noted that the environmental implications of this scenario are much less clear-cut. As such, there is an urgent need to understand the full implications of this scenario, so that upland stakeholders can adequately prepare, and policy-makers can better evaluate the likely implications of different policy options. The paper concludes that in future, upland scenario research needs to: (1) better integrate in-depth and representative participation from stakeholders during both scenario development and evaluation; and (2) make more effective use of visualisation techniques and simulation models

    The Observed and Predicted Spatial Distribution of Milky Way Satellite Galaxies

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    We review evidence that the census of Milky Way satellites similar to those known may be incomplete at low latitude due to obscuration and in the outer halo due to a decreasing sensitivity to dwarf satellites with distance. We evaluate the possible impact that incompleteness has on comparisons with substructure models by estimating corrections to the known number of dwarfs using empirical and theoretical models. If we assume that the true distribution of Milky Way satellites is uniform with latitude, then we estimate a 33% incompleteness in the total number of dwarfs due to obscuration at low latitude. Similarly, if we suppose that the radial distribution of Milky Way satellites matches that of M31, or that of the oldest sub-halos or the most massive sub-halos in a simulation, we estimate a total number of Milky Way dwarfs ranging from 1 -- 3 times the known population. Although the true level of incompleteness is quite uncertain, the fact that our extrapolations yield average total numbers of MW dwarfs that are realistically 1.5 -- 2 times the known population, shows that incompleteness needs to be taken seriously when comparing to models of dwarf galaxy formation. Interestingly, the radial distribution of the oldest sub-halos in a Lambda+CDM simulation of a Milky Way-like galaxy possess a close match to the observed distribution of M31's satellites, which suggests that reionization may be an important factor controlling the observability of sub-halos. We also assess the prospects for a new SDSS search for Milky Way satellites to constrain the possible incompleteness in the outer halo.Comment: 9 pages, 7 figures. Replaced with MNRAS accepted versio

    Another Shipment of Six Short-Period Giant Planets from TESS

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    We present the discovery and characterization of six short-period, transiting giant planets from NASA\u27s Transiting Exoplanet Survey Satellite (TESS) -- TOI-1811 (TIC 376524552), TOI-2025 (TIC 394050135), TOI-2145 (TIC 88992642), TOI-2152 (TIC 395393265), TOI-2154 (TIC 428787891), & TOI-2497 (TIC 97568467). All six planets orbit bright host stars (8.

    Faint dwarfs as a test of DM models: WDM versus CDM

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    We use high-resolution Hydro+N-Body cosmological simulations to compare the assembly and evolution of a small field dwarf (stellar mass ∼106−7M⊙, total mass 1010M⊙) in Λ-dominated cold dark matter (CDM) and 2keV warm dark matter (WDM) cosmologies. We find that star formation (SF) in the WDM model is reduced and delayed by 1-2Gyr relative to the CDM model, independently of the details of SF and feedback. Independent of the dark matter (DM) model, but proportionally to the SF efficiency, gas outflows lower the central mass density through ‘dynamical heating', such that all realizations have circular velocities <20 km s−1 at 500pc, in agreement with local kinematic constraints. As a result of dynamical heating, older stars are less centrally concentrated than younger stars, similar to stellar population gradients observed in nearby dwarf galaxies. Introducing an important diagnostic of SF and feedback models, we translate our simulations into artificial colour-magnitude diagrams and star formation histories (SFHs) in order to directly compare to available observations. The simulated galaxies formed most of their stars in many ∼10Myr long bursts. The CDM galaxy has a global SFH, H i abundance and Fe/H and alpha-elements distribution well matched to current observations of dwarf galaxies. These results highlight the importance of directly including ‘baryon physics' in simulations when (1) comparing predictions of galaxy formation models with the kinematics and number density of local dwarf galaxies and (2) differentiating between CDM and non-standard models with different DM or power spectr

    Participatory scenario development for environmental management:A methodological framework illustrated with experience from the UK uplands

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    A methodological framework is proposed for participatory scenario development on the basis of evidence from the literature, and is tested and refined through the development of scenarios for the future of UK uplands. The paper uses a review of previous work to justify a framework based around the following steps: i) define context and establish whether there is a basis for stakeholder engagement in scenario development; ii) systematically identify and represent relevant stakeholders in the process; iii) define clear objectives for scenario development with stakeholders including spatial and temporal boundaries; iv) select relevant participatory methods for scenario development, during initial scenario construction, evaluation and to support decision-making based on scenarios; and v) integrate local and scientific knowledge throughout the process. The application of this framework in case study research suggests that participatory scenario development has the potential to: i) make scenarios more relevant to stakeholder needs and priorities; ii) extend the range of scenarios developed; iii) develop more detailed and precise scenarios through the integration of local and scientific knowledge; and iv) move beyond scenario development to facilitate adaptation to future change. It is argued that participatory scenario development can empower stakeholders and lead to more consistent and robust scenarios that can help people prepare more effectively for future change

    Dirac and Weyl Equations on a Lattice as Quantum Cellular Automata

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    A discretized time evolution of the wave function for a Dirac particle on a cubic lattice is represented by a very simple quantum cellular automaton. In each evolution step the updated value of the wave function at a given site depends only on the values at the nearest sites, the evolution is unitary and preserves chiral symmetry. Moreover, it is shown that the relationship between Dirac particles and cellular automata operating on two component objects on a lattice is indeed very close. Every local and unitary automaton on a cubic lattice, under some natural assumptions, leads in the continuum limit to the Weyl equation. The sum over histories is evaluated and its connection with path integrals and theories of fermions on a lattice is outlined.Comment: 6, RevTe

    A place-based approach to payments for ecosystem services

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    Payment for Ecosystem Services (PES) schemes are proliferating but are challenged by insufficient attention to spatial and temporal inter-dependencies, interactions between different ecosystems and their services, and the need for multi-level governance. To address these challenges, this paper develops a place-based approach to the development and implementation of PES schemes that incorporates multi-level governance, bundling or layering of services across multiple scales, and shared values for ecosystem services. The approach is evaluated and illustrated using case study research to develop an explicitly place-based PES scheme, the Peatland Code, owned and managed by the International Union for the Conservation of Nature’s UK Peatland Programme and designed to pay for restoration of peatland habitats. Buyers preferred bundled schemes with premium pricing of a primary service, contrasting with sellers’ preferences for quantifying and marketing services separately in a layered scheme. There was limited awareness among key business sectors of dependencies on ecosystem services, or the risks and opportunities arising from their management. Companies with financial links to peatlands or a strong environmental sustainability focus were interested in the scheme, particularly in relation to climate regulation, water quality, biodiversity and flood risk mitigation benefits. Visitors were most interested in donating to projects that benefited wildlife and were willing to donate around £2 on-site during a visit. Sellers agreed a deliberated fair price per tonne of CO2 equivalent from £11.18 to £15.65 across four sites in Scotland, with this range primarily driven by spatial variation in habitat degradation. In the Peak District, perceived declines in sheep and grouse productivity arising from ditch blocking led to substantially higher prices, but in other regions ditch blocking was viewed more positively. The Peatland Code was developed in close collaboration with stakeholders at catchment, landscape and national scales, enabling multi-level governance of the management and delivery of ecosystem services across these scales. Place-based PES schemes can mitigate negative trade-offs between ecosystem services, more effectively include cultural ecosystem services and engage with and empower diverse stakeholders in scheme design and governance

    Stage and treatment variation with age in postmenopausal women with breast cancer: compliance with guidelines

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    Breast cancer-specific mortality is static in older women despite having fallen in younger age groups, possibly due to lack of screening and differences in treatment. This study compared stage and treatment between two cohorts of postmenopausal women (55–69 vs 470 years) in a single cancer network over 6 months. A total of 378 patients were studied (470: N ¼ 167, 55–69 years: N ¼ 210). Older women presented with more advanced disease (470: metastatic/locally advanced 12%, 55–69 years: 3%, Po0.01). Those with operable cancer had a worse prognosis (Nottingham Prognostic Index (NPI) 470: median NPI 4.4, 55–69 years: 4.25, Po0.03). These stage differences were partially explained by higher screening rates in the younger cohort. Primary endocrine therapy was used in 42% of older patients compared with 3% in the younger group (Po0.001). Older women with cancers suitable for breast conservation were more likely to choose mastectomy (470: 57.5% mastectomy rate vs 55–69 years: 20.6%, Po0.01). Nodal surgery was less frequent in older patients (470: 6.7% no nodal surgery, 55–69 years: 0.5%, Po0.01) and was more likely to be inadequate (470: 10.7% o4 nodes excised, 55–69 years: 3.4%, Po0.02). In summary, older women presented with more advanced breast cancer, than younger postmenopausal women and were treated less comprehensively
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