1,008 research outputs found

    How can field margin management contribute to invertebrate biodiversity?

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    Farmland invertebrates are vital for healthy ecosystem functioning. Many groups have declined due to agricultural intensification. Arable field margins potentially can increase food resources and provide winter refuges for invertebrates. They might also buffer them from agrochemical applications and farm operations. This chapter describes a series of field and farm-scale experiments which show that ways in which arable field margins are established and managed can have profound effects on their invertebrate assemblages. Field margin swards established by sowing with a grass and wildflower seed mixture attracted more butterflies than naturally regenerated swards. In the short term, larger and more species-rich invertebrate assemblages were fostered on unmanaged margins than on those managed by cutting. The timing of cutting was critical, with mid-summer cutting having the most persistent, negative effects on invertebrates, while cutting in spring and autumn was generally less damaging and may help maintain sward species richness. Fallowed land (set-aside) configured as blocks rather than margins constituted qualitatively different habitats for invertebrates. Margin width had complex effects on invertebrate abundance and species richness. Boundary hedgerows increased numbers of most invertebrate groups in the adjacent margin. The chapter suggests that blanket management approaches for invertebrates at the farm scale are not optimal. A diverse farmed landscape, with margins of different sizes and different sward structures, will provide for the different ecological requirements of invertebrate populations, and promote their diversity in the characteristically unstable environment of arable systems

    Similarities and differences of pumping conventional and self-compacting concrete

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    In Practice, Self-Compacting Concrete (SCC) is Considered as a Simple Extension of Conventional Vibrated Concrete (CVC) When Pumping is Concerned. the Same Equipment, Materials, Pumping Procedures and Guidelines Used for CVC Are Applied When Pumping SCC. on the Other Hand, It Has Been Clearly Shown that the Rheological Properties and the Mix Design of SCC Are Different Than CVC. Can the Same Pumping Principles Employed for CVC Be Applied for SCC? This Paper Compares the Some Published Results of Pumping of CVC with Those for SCC. a First Striking Difference between Pumping of CVC and SCC is the Flow Behaviour in the Pipes. the Flow of CVC is a Plug, Surrounded by a Lubricating Layer, While during the Flow of SCC, Part of the Concrete Volume itself is Sheared Inside the Pipe. as a Result, the Importance of Viscosity Increases in Case of SCC. Due to the Low Yield Stress of SCC, the Behaviour in Bends is Different, But Quite Complex to Study. Due to the Lower Content of Aggregate and Better Stability of SCC, as It is Less Prone to Internal Water Migration, Blocking is Estimated to Occur at Lower Frequency in Case of SCC. © RILEM 2010

    Ampasambazimba

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    6 p. : 2 maps ; 24 cm.Includes bibliographical references (p. 6)."A radiocarbon age determination of 1035 [+ or =] 50 years B.P. is given for a lemuroid bone from the prolific subfossil site at Ampasambazimba, Miarinarivo Province, Malagasy Republic. This is the first absolute date to have been obtained for a central plateau site, and, it is suggested, the most recent yet acquired for the subfossil lemuroids"--P. [1]

    Waiting to be discovered? Community partnerships, the facilitation of diverse memory, and reflections on academic success and failure

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    This is the final version. Available from MDPI via the DOI in this record. Data Availability Statement: The raw data supporting the conclusions of this article will be made available by the author on request.Community partnerships, based on ‘the collaborative turn’ in academic research, are an increasingly common framework through which ‘bottom-up’ histories, particularly of diverse and/or more marginalised communities, are being told. This article is about the ‘doing’ of this type of work. It focuses on the question: what lessons can be made visible when attempted cooperation fails to deliver the outcomes initially hoped for? Firstly, this article outlines the events and activities undertaken by the authors in exploring the ways that ephemera and other objects can be used to understand and transmit the historical experiences of communities often on the periphery of mainstream war commemoration. It will discuss the ways in which connections with these communities were built, with the aim of undertaking several creative writing workshops, leading to a co-produced publication of the participants’ material. Secondly, as part of a broader acknowledgment of the possibility of failure and its benefits, it will explore why some of these creative workshop efforts failed to meet expectations and outline a series of recommendations for other historians and community-orientated projects to consider for future activities.Arts and Humanities Research Counci

    Physiological regulation of evaporative water loss in endotherms: Is the little red kaluta (Dasykaluta rosamondae) an exception or the rule?

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    It is a central paradigm of comparative physiology that the effect of humidity on evaporative water loss (EWL) is determined for most mammals and birds, in and below thermoneutrality, essentially by physics and is not under physiological regulation. Fick's law predicts that EWL should be inversely proportional to ambient relative humidity (RH) and linearly proportional to the water vapour pressure deficit (Δwvp) between animal and air. However, we show here for a small dasyurid marsupial, the little kaluta (Dasykaluta rosamondae), that EWL is essentially independent of RH (and Δwvp) at low RH (as are metabolic rate and thermal conductance). These results suggest regulation of a constant EWL independent of RH, a hitherto unappreciated capacity of endothermic vertebrates. Independence of EWL from RH conserves water and heat at low RH, and avoids physiological adjustments to changes in evaporative heat loss such as thermoregulation. Re-evaluation of previously published data for mammals and birds suggests that a lesser dependence of EWL on RH is observed more commonly than previously thought, suggesting that physiological independence of EWL of RH is not just an unusual capacity of a few species, such as the little kaluta, but a more general capability of many mammals and birds

    Auto-calibration of ultrasonic lubricant-film thickness measurements

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    The measurement of oil film thickness in a lubricated component is essential information for performance monitoring and design. It is well established that such measurements can be made ultrasonically if the lubricant film is modelled as a collection of small springs. The ultrasonic method requires that component faces are separated and a reference reflection recorded in order to obtain a reflection coefficient value from which film thickness is calculated. The novel and practically useful approach put forward in this paper and validated experimentally allows reflection coefficient measurement without the requirement for a reference. This involves simultaneously measuring the amplitude and phase of an ultrasonic pulse reflected from a layer. Provided that the acoustic properties of the substrate are known, the theoretical relationship between the two can be fitted to the data in order to yield reflection coefficient amplitude and phase for an infinitely thick layer. This is equivalent to measuring a reference signal directly, but importantly does not require the materials to be separated. The further valuable aspect of this approach, which is demonstrated experimentally, is its ability to be used as a self-calibrating routine, inherently compensating for temperature effects. This is due to the relationship between the amplitude and phase being unaffected by changes in temperature which cause unwanted changes to the incident pulse. Finally, error analysis is performed showing how the accuracy of the results can be optimized. A finding of particular significance is the strong dependence of the accuracy of the technique on the amplitude of reflection coefficient input data used. This places some limitations on the applicability of the technique. © 2008 IOP Publishing Ltd

    Identification of a lipid-rich depot in the orbital cavity of the thirteen-lined ground squirrel

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    We discovered a previously undescribed orbital lipid depot in the thirteen-lined ground squirrel during the first ever magnetic resonance image (MRI) of this common experimental model of mammalian hibernation. In animals housed at constant ambient temperatures (5°C or 25°C, 12 h:12 h light:dark photoperiod), the volume of this depot increased in the autumn and decreased in the spring, suggesting an endogenous circannual pattern. Water-fat MRI revealed that throughout the year this depot is composed of ∼40% lipid, similar to brown adipose tissue (BAT). During arousal from torpor, thermal images showed higher surface temperatures near this depot before the rest of the head warmed, suggesting a thermoregulatory function. This depot, however, does not contain uncoupling protein 1, a BAT biomarker, or uncoupling protein 3. Histology shows blood vessels in close proximity to each other, suggesting it may serve as a vascular rete, perhaps to preferentially warm the eye and brain during arousals

    ICTV Virus Taxonomy Profile : Parvoviridae

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    Members of the family Parvoviridae are small, resilient, non-enveloped viruses with linear, single-stranded DNA genomes of 4-6 kb. Viruses in two subfamilies, the Parvovirinae and Densovirinae, are distinguished primarily by their respective ability to infect vertebrates (including humans) versus invertebrates. Being genetically limited, most parvoviruses require actively dividing host cells and are host and/or tissue specific. Some cause diseases, which range from subclinical to lethal. A few require co-infection with helper viruses from other families. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the Parvoviridae, which is available at www.ictv.global/report/parvoviridae.Non peer reviewe

    Measurement of the 70Ge(n,γ) cross section up to 300 keV at the CERN n_TOF facility

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    Neutron capture data on intermediate mass nuclei are of key importance to nucleosynthesis in the weak component of the slow neutron capture processes, which occurs in massive stars. The (n,γ) cross section on 70Ge, which is mainly produced in the s process, was measured at the neutron time-of-flight facility n_TOF at CERN. Resonance capture kernels were determined up to 40 keV neutron energy and average cross sections up to 300 keV. Stellar cross sections were calculated from kT =5 keV tokT =100 keV and are in very good agreement with a previous measurement by Walter and Beer (1985) and recent evaluations. Average cross sectionsareinagreementwithWalterandBeer(1985)overmostoftheneutronenergyrangecovered,whilethey aresystematicallysmallerforneutronenergiesabove150keV.Wehavecalculatedisotopicabundancesproduced in s-process environments in a 25 solar mass star for two initial metallicities (below solar and close to solar). While the low metallicity model reproduces best the solar system germanium isotopic abundances, the close to solar model shows a good global match to solar system abundances in the range of mass numbers A=60–80.Austrian Science Fund J3503Adolf Messer Foundation ST/M006085/1European Research Council ERC2015-StGCroatian Science Foundation IP-2018-01-857
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