3,360 research outputs found

    Nanoscale assembly of lanthanum silica with dense and porous interfacial structures

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    This work reports on the nanoscale assembly of hybrid lanthanum oxide and silica structures, which form patterns of interfacial dense and porous networks. It was found that increasing the molar ratio of lanthanum nitrate to tetraethyl orthosilicate (TEOS) in an acid catalysed sol-gel process alters the expected microporous metal oxide silica structure to a predominantly mesoporous structure above a critical lanthanum concentration. This change manifests itself by the formation of a lanthanum silicate phase, which results from the reaction of lanthanum oxide nanoparticles with the silica matrix. This process converts the microporous silica into the denser silicate phase. Above a lanthanum to silica ratio of 0.15, the combination of growth and microporous silica consumption results in the formation of nanoscale hybrid lanthanum oxides, with the inter-nano-domain spacing forming mesoporous volume. As the size of these nano-domains increases with concentration, so does the mesoporous volume. The absence of lanthanum hydroxide (La(OH)(3)) suggests the formation of La2O3 surrounded by lanthanum silicate

    True‐to‐Hume Laws and the Open‐Future (Or Hypertemporal Humeanism)

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    Abstract:Take open‐future Humeanism to comprise the following four tenets: (T1) that truth supervenes on a mosaic of local particular matters of fact (T2) that there are no necessary connections between distinct existences (T3) that there is a dynamic present moment, and (T4) that there are no future facts; that is, contingent propositions about the future obtain truth values only when their referents are actualised (Tooley 1997). Prima facie this is a deeply problematic metaphysic for the Humean, since given that the widely accepted Humean conception (that of David Lewis 1986a) takes all truths (inclusive of nomological truths) to supervene on an omnitemporal mosaic of local particular matters of fact, if there are no future facts then the Humean can neither provide laws of nature, nor justify many everyday inductive inferences (Hüttemann 2014). However, I argue that this eternalist metaphysic is in tension with at least one of Hume’s central metaphysical claims concerning causation e.g., that causal regularities may cease to hold at any time. In this paper I propose and defend one possible open‐future Humean metaphysic which admits of ‘true‐to‐Hume’ causal and nomological facts. Furthermore, although I am happy to concede that induction is problematic for the open‐future Humean, I demonstrate that it poses no greater threat to the open‐future conception than it does to the popular Lewisian conception of natural law

    Tendencies, determinism, and sporting prowess – a response to Mumford and Anjum

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    Abstract: In Getting Causes from Powers (2011) Stephen Mumford and Rani Anjum published a novel approach to the metaphysics of dispositional properties, according to which causal powers are to be viewed as vectors. More recently they have employed a similar system to represent prowess in sport. In this paper l discuss the Mumford/Anjum ‘tendential theory of sporting prowess’. I question their motivation for the tendencies account, concluding (contra Mumford and Anjum) that a belief in determinism would not take away from the enjoyment of spectator sports. Nonetheless, I deem the tendential theory of prowess plausible. In addition to criticising their motivation, then, I develop the Mumford/Anjum thesis, applying the multi‐dimensional aspect they themselves apply to ‘complex causal situations’, to the metaphysic of sporting prowess

    Prophets and Priests of the Nation: Naguib Mahfouz’s Karnak Café and the 1967 Crisis in Egypt

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    Similarities between religion and nationalism are well known but not well understood. They can be explained by drawing on Pierre Bourdieu's sociological theory in order to consider symbolic interests and the strategies employed to advance them. In both religion and nationalism, the “strategy of the prophets” relies on charisma while the “strategy of the priests” relies on cultural capital. In 20th-century Egypt, nationalism permitted intellectuals whose cultural capital was mainly secular, such as Naguib Mahfouz, to become “priests of the nation” in order to compete with the ʿulamaʾ for prestige and influence. However, it severely limited their autonomy, particularly after Nasser took power and became a successful nationalist prophet. Mahfouz's novel Al-Karnak, which explores the fate of the Nasser regime's political prisoners and the effects of Egypt's 1967 military defeat, reflects this limitation. Under a nationalist regime, the film adaptation of the novel contributed to Mahfouz's heteronomy

    STRAD Pseudokinases Regulate Axogenesis and LKB1 Stability

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    BACKGROUND: Neuronal polarization is an essential step of morphogenesis and connectivity in the developing brain. The serine/threonine kinase LKB1 is a key regulator of cell polarity, metabolism, tumorigenesis, and is required for axon formation. It is allosterically regulated by two related and evolutionarily conserved pseudokinases, STe20-Related ADapters (STRADs) α and β. The roles of STRADα and STRADβ in the developing nervous system are not fully defined, nor is it known whether they serve distinct functions. RESULTS: We find that STRADα is highly spliced and appears to be the primal STRAD paralog. We report that each STRAD is sufficient for axogenesis and promoting cell survival in the developing cortex. We also reveal a reciprocal protein-stabilizing relationship in vivo between LKB1 and STRADα, whereby STRADα specifically maintains LKB1 protein levels via cytoplasmic compartmentalization. CONCLUSIONS: We demonstrate a novel role for STRADβ in axogenesis and also show for the first time in vivo that STRADα, but not STRADβ, is responsible for LKB1 protein stability

    Dispositions and the principle of least action revisited

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    Please refer to full text to view abstrac

    Near-UV and optical observations of the transiting exoplanet TrES-3b

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    We observed nine primary transits of the hot Jupiter TrES-3b in several optical and near-UV photometric bands from 2009 June to 2012 April in an attempt to detect its magnetic field. Vidotto, Jardine and Helling suggest that the magnetic field of TrES-3b can be constrained if its near-UV light curve shows an early ingress compared to its optical light curve, while its egress remains unaffected. Predicted magnetic field strengths of Jupiter-like planets should range between 8 G and 30 G. Using these magnetic field values and an assumed B_star of 100 G, the Vidotto et al. method predicts a timing difference of 5-11 min. We did not detect an early ingress in our three nights of near-UV observations, despite an average cadence of 68 s and an average photometric precision of 3.7 mmag. However, we determined an upper limit of TrES-3b's magnetic field strength to range between 0.013 and 1.3 G (for a 1-100 G magnetic field strength range for the host star, TrES-3) using a timing difference of 138 s derived from the Nyquist-Shannon sampling theorem. To verify our results of an abnormally small magnetic field strength for TrES-3b and to further constrain the techniques of Vidotto et al., we propose future observations of TrES-3b with other platforms capable of achieving a shorter near-UV cadence. We also present a refinement of the physical parameters of TrES-3b, an updated ephemeris and its first published near-UV light curve. We find that the near-UV planetary radius of Rp = 1.386+0.248-0.144 RJup is consistent with the planet's optical radius.Comment: Accepted for Publication in Monthly Notices of the Royal Astronomical Society (2012 September 21). 13 pages, 5 figure

    Optimizing the bioenergy water footprint by selecting SRC willow canopy phenotypes: regional scenario simulations

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    © The Author(s) 2019. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.Background and Aims: Bioenergy is central for the future energy mix to mitigate climate change impacts; however, its intricate link with the water cycle calls for an evaluation of the carbon–water nexus in biomass production. The great challenge is to optimize trade-offs between carbon harvest and water use by choosing cultivars that combine low water use with high productivity. Methods: Regional scenarios were simulated over a range of willow genotype × environment interactions for the major UK soil × climate variations with the process-based model LUCASS. Soil available water capacity (SAWC) ranged from 51 to 251 mm and weather represented the north-west (wet, cool), north-east (dry, cool), south-west (wet, warm) and south-east (dry, warm) of the UK. Scenario simulations were evaluated for small/open narrow-leaf (NL) versus large/closed broad-leaf (BL) willow canopy phenotypes using baseline (1965–89) and warmer recent (1990–2014) weather data. Key Results: The low productivity under baseline climate in the north could be compensated by choosing BL cultivars (e.g. ‘Endurance’). Recent warmer climate increased average productivity by 0.5–2.5 t ha−1, especially in the north. The modern NL cultivar ‘Resolution’ had the smallest and most efficient water use. On marginal soils (SAWC <100 mm), yields remained below an economic threshold of 9 t ha−1 more frequently under baseline than recent climate. In the drought-prone south-east, ‘Endurance’ yielded less than ‘Resolution’, which consumed on average 17 mm year−1 less water. Assuming a planting area of 10 000 ha, in droughty years between 1.3 and 4.5 × 106 m3 of water could be saved, with a small yield penalty, for ‘Resolution’. Conclusions: With an increase in air temperature and occasional water scarcities expected with climate change, high-yielding NL cultivars should be the preferred choice for sustainable use of marginal lands and reduced competition with agricultural food crops.Peer reviewedFinal Published versio

    The histone deacetylase inhibitor, romidepsin, as a potential treatment for pulmonary fibrosis

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    Idiopathic pulmonary fibrosis (IPF) is a progressive disease that usually affects elderly people. It has a poor prognosis and there are limited therapies. Since epigenetic alterations are associated with IPF, histone deacetylase (HDAC) inhibitors offer a novel therapeutic strategy to address the unmet medical need. This study investigated the potential of romidepsin, an FDA-approved HDAC inhibitor, as an anti-fibrotic treatment and evaluated biomarkers of target engagement that may have utility in future clinical trials. The anti-fibrotic effects of romidepsin were evaluated both in vitro and in vivo together with any harmful effect on alveolar type II cells (ATII). Bronchoalveolar lavage fluid (BALF) from IPF or control donors was analyzed for the presence of lysyl oxidase (LOX). In parallel with an increase in histone acetylation, romidepsin potently inhibited fibroblast proliferation, myofibroblast differentiation and LOX expression. ATII cell numbers and their lamellar bodies were unaffected. In vivo, romidepsin inhibited bleomycin-induced pulmonary fibrosis in association with suppression of LOX expression. LOX was significantly elevated in BALF of IPF patients compared to controls. These data show the anti-fibrotic effects of romidepsin, supporting its potential use as novel treatment for IPF with LOX as a companion biomarker for evaluation of early on-target effects
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