1,237 research outputs found

    Apollo command module mockup flammability tests

    Get PDF
    Apollo command module mockup flammability tests using three different atmosphere

    Ontological dependence in a spacetime-world

    Get PDF
    Priority Monism (hereafter, ‘Monism’), as defined by Jonathan Schaffer (Philos Rev 119:131–176, 2010), has a number of components. It is the view that: the cosmos exists; the cosmos is a maximal actual concrete object, of which all actual concrete objects are parts; the cosmos is basic—there is no object upon which the cosmos depends, ontologically; ontological dependence is a primitive and unanalysable relation. In a recent attack, Lowe (Spinoza on monism. Palgave Macmillan, London, pp 92–122, 2012) has offered a series of arguments to show that Monism fails. He offers up four tranches of argument, with different focuses. These focal points are: (1) being a concrete object; (2) aggregation and dependence; (3) analyses of ontological dependence; (4) Schaffer’s no-overlap principle. These are all technical notions, but each figures at the heart of a cluster of arguments that Lowe puts forward. To respond, I work through each tranche of argument in turn. Before that, in the first section, I offer a cursory statement of Monism, as Schaffer presents it in his 2010 paper, Monism: The Priority of the Whole. I then respond to each of Lowe’s criticisms in turn, deploying material from Schaffer’s 2009 paper Spacetime: the One Substance, as well as various pieces of conceptual machinery from Lowe’s own works (The possibility of metaphysics. Clarendon, Oxford, 1998, 2010) to deflect Lowe’s (Spinoza on monism. Palgave Macmillan, London, pp 92–122, 2012) attacks. In the process of defending Monism from Lowe (Spinoza on monism. Palgave Macmillan, London, pp 92–122, 2012), I end up offering some subtle refinements to Schaffer’s (Philos Rev 119:131–176, 2010) view and explain how the resulting ‘hybrid’ view fares in the wider dialectic

    One-step isolation and biochemical characterization of a highlyactive plant PSII monomeric core

    Get PDF
    We describe a one-step detergent solubilization protocol for isolating a highly active form of Photosystem II (PSII) from Pisum sativum L. Detailed characterization of the preparation showed that the complex was a monomer having no light harvesting proteins attached. This core reaction centre complex had, however, a range of low molecular mass intrinsic proteins as well as the chlorophyll binding proteins CP43 and CP47 and the reaction centre proteins D1 and D2. Of particular note was the presence of a stoichiometric level of PsbW, a low molecular weight protein not present in PSII of cyanobacteria. Despite the high oxygen evolution rate, the core complex did not retain the PsbQ extrinsic protein although there was close to a full complement of PsbO and PsbR and partial level of PsbP. However, reconstitution of PsbP and PsbPQ was possible. The presence of PsbP in absence of LHCII and other chlorophyll a/b binding proteins confirms that LHCII proteins are not a strict requirement for the assembly of this extrinsic polypeptide to the PSII core in contrast with the conclusion of Caffarri et al. (2009)

    Theoretical studies of the historical development of the accounting discipline: a review and evidence

    Get PDF
    Many existing studies of the development of accounting thought have either been atheoretical or have adopted Kuhn's model of scientific growth. The limitations of this 35-year-old model are discussed. Four different general neo-Kuhnian models of scholarly knowledge development are reviewed and compared with reference to an analytical matrix. The models are found to be mutually consistent, with each focusing on a different aspect of development. A composite model is proposed. Based on a hand-crafted database, author co-citation analysis is used to map empirically the entire literature structure of the accounting discipline during two consecutive time periods, 1972–81 and 1982–90. The changing structure of the accounting literature is interpreted using the proposed composite model of scholarly knowledge development

    Improving methods and indicators for evaluating coastal water eutrophication: a pilot study in the Gulf of Maine

    Get PDF
    Study Goals and Objectives: 1) Improve existing nutrient-related eutrophication assessment methods, updating (from early 1990s to early 2000s) the eutrophication assessment for systems included in the study with the improved method. 2) Develop a human-use/socioeconomic indicator to complement the assessment indicator. The human-use indicator was developed to evaluate costs of nutrient-related degradation in coastal waters and to put the issue into a broader context relevant to the interested public and legislators as well as to scientists. 3) Project objectives included collecting existing water quality data, developing an accessible database appropriate for application to a national study, and applying the assessment methods to 14 coastal systems – nine systems north of Cape Cod and five systems south. The geographical distribution of systems was used to examine potential regional differences in condition. 4) The intent is to use the lessons learned in this pilot study on a national scale to guide completion of an update of the 1999 National Estuarine Eutrophication Assessment

    Infiltration efficiency and subsurface water processes of a sustainable drainage system and consequences to flood management

    Get PDF
    With increased intensity rainfall events globally and urban expansion decreasing permeable surfaces, there is an increasing problem of urban flooding. This study aims to better understand rainfall infiltration into a Sustainable Drainage System (SuDS) permeable pavement, compared with an adjacent Green Area of made ground, in relationship to groundwater levels below both areas. Both areas were instrumented with soil water content and matric potential sensors and four shallow boreholes were instrumented with groundwater level sensors. Surface infiltration rates were measured using a double‐ring infiltrometer. Results showed that average infiltration rates of the SuDS (1,925 mm/hr) were significantly higher than the Green Area (56 mm/hr). The SuDS was well designed to transfer rainfall rapidly to the aquifer below, where groundwater levels rapidly rose within 1 hr of a 1 in 30 year event (32.8 mm/hr). In comparison, soil compaction of the made ground Green Area decreased infiltration rates, but still enabled the majority of rainfall events to infiltrate. The aquifer below the Green Area responded more slowly, as lower matrix potentials facilitated water retention in the soil profile, slowing water draining to the aquifer. This work reiterates the importance of ensuring a 1 m separation depth between the base of the SuDS infiltration zone and aquifer depth

    Search for Light Gluinos via the Spontaneous Appearance of pi+pi- Pairs with an 800 GeV/c Proton Beam at Fermilab

    Get PDF
    We searched for the appearance of pi+pi- pairs with invariant mass greater than 648 MeV in a neutral beam. Such an observation could signify the decay of a long-lived light neutral particle. We find no evidence for this decay. Our null result severely constrains the existence of an R0 hadron, which is the lightest bound state of a gluon and a light gluino, and thereby also the possibility of a light gluino. Depending on the photino mass, we exclude the R0 in the mass and lifetime ranges of 1.2 -- 4.6 GeV and 2E-10 -- 7E-4 seconds, respectively. (To Appear in Phys. Rev. Lett.)Comment: Documentstyle aps,epsfig,prl (revtex), 6 pages, 7 figure

    Zeroing the Stellar Isochrone Scale: The Red Giant Clump Luminosity at Intermediate Metallicity

    Full text link
    The color-magnitude diagrams of the open clusters NGC 2420 and NGC 2506 have been investigated as intermediate links between the solar neighborhood and the Magellanic Clouds. Two sets of theoretical isochrones which include convective overshoot are zeroed to the sun at solar abundance and to the unevolved main sequence dwarfs of the Hipparcos catalog at [Fe/H] = -0.4, requiring a differential of 0.4 mag between the unevolved main sequences at a given color. Adopting E(B-V) = 0.04 and [Fe/H] = -0.39 for NGC 2506 and 0.04 and -0.29 for NGC 2420,the respective apparent moduli are 12.70 and 12.15, while the ages of both clusters are approximately 1.9 +/- 0.2 or 2.2 +/- 0.2 Gyr, depending on the choice of isochrones. From the composite giant branch of the two clusters, the mean clump magnitudes in V and I are found to be 0.47 and -0.48 (-0.17,+0.14). Applying a metallicity correction to the M_I values, the cluster sample of Udalski (1998) leads to (m-M)_0 = 18.42 (+0.17,--0.15) and 18.91 (+0.18,--0.16) for the LMC and SMC, respectively. A caveat to this discussion and to the claim that clusters of the same abundance and age are identical is the observation that the (V-I) colors of the red giants in NGC 2506 are significantly redder at a given (B-V) than the giants in clusters of comparable age and/or metallicity. If the CCD photometry for NGC 2506 is tied to the standard system rather than using a general cluster relation between (B-V) and (V-I), the M_I for the clump will decrease by 0.1 mag.Comment: 1 table, 12 figures. Replaced 20-jan-99 by version with all figures. Accepted for April 1999 Astronomical Journa

    Light Gluino Search for Decays Containing pi+pi- or pi0 from a Neutral Hadron Beam at Fermilab

    Full text link
    We report on two null searches, one for the spontaneous appearance of π+π−\pi^+\pi^- pairs, another for a single π0\pi^0, consistent with the decay of a long-lived neutral particle into hadrons and an unseen neutral particle. For the lowest level gluon-gluino bound state, known as the R0R^0, we exclude the decays R0→π+Ï€âˆ’Îł~R^0\to \pi^+\pi^-\tilde{\gamma} and R0→π0Îł~R^0\to \pi^0\tilde{\gamma} for the masses of R0R^0 and Îł~\tilde{\gamma} in the theoretically allowed range. In the most interesting R0R^0 mass range, ≀3GeV/c2\leq 3 GeV/c^2, we exclude R0R^0 lifetimes from 3×10−103\times 10^{-10} seconds to as high as 10−310^{-3} seconds, assuming perturbative QCD production for the R0R^0.Comment: 15 pages, 7 figure
    • 

    corecore