20 resultados para Ends of Spaces


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In this review paper, the aim is to compare and contrast fossil pollen evidence for Holocene rainforest ecotonal dynamics at opposite ends of the Amazon basin – the southern ecotone in NE lowland Bolivia versus the northern ecotone in lowland Colombia. During the Holocene, tropical South America experienced major changes in precipitation (Silva Dias et al. 2009). Consideration of Amazonian rainforest dynamics over this time-frame may therefore provide important insights into rainforest responsiveness to climate change.

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This paper reviews late Roman `nail-cleaner strap-ends', a group of objects first discussed by Hawkes and Dunning (1961). The precise function of these objects is unclear as their shape suggests use as toilet instruments but the split socket suggests that they were part of belt-fittings. We suggest a detailed typology and discuss the dating evidence and the spatial distribution of the type. Regardless of their precise function, it is argued in this paper that nail-cleaner strap-ends of this type are unique to late Roman Britain and thus represent a distinct regional type. The use of nail-cleaner strap-ends can be viewed in the context of gender associations, military status and religious beliefs.

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Magnetic clouds are a subset of interplanetary coronal mass ejections characterized by a smooth rotation in the magnetic field direction, which is interpreted as a signature of a magnetic flux rope. Suprathermal electron observations indicate that one or both ends of a magnetic cloud typically remain connected to the Sun as it moves out through the heliosphere. With distance from the axis of the flux rope, out toward its edge, the magnetic field winds more tightly about the axis and electrons must traverse longer magnetic field lines to reach the same heliocentric distance. This increased time of flight allows greater pitch-angle scattering to occur, meaning suprathermal electron pitch-angle distributions should be systematically broader at the edges of the flux rope than at the axis. We model this effect with an analytical magnetic flux rope model and a numerical scheme for suprathermal electron pitch-angle scattering and find that the signature of a magnetic flux rope should be observable with the typical pitch-angle resolution of suprathermal electron data provided ACE's SWEPAM instrument. Evidence of this signature in the observations, however, is weak, possibly because reconnection of magnetic fields within the flux rope acts to intermix flux tubes.

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Copyright protects the rights and interests of authors on their original works of authorship such as literary, dramatic, musical, artistic, and certain other intellectual works including architectural works and designs. It is automatic once a tangible medium of expression in any form of an innovative material, which conforms the Copyright Designs and Patents Act 1988 (CDPA 1988), is created. This includes the building, the architectural plans and drawings. There is no official copyright registry, no requirements on any fees need to be paid and they can be published or unpublished materials. Copyrights owners have the rights to control the reproduction, display, publication, and even derivation of the design. However, there are limitations on the rights of the copyright owners concerning copyrights infringements. Infringement of copyright is an unauthorised violation of the exclusive rights of the copyright author. Architects and engineers depend on copyright law to protect their works and design. Copyrights are protected on the arrangements of spaces and elements as well as the overall form of the architectural design. However, it does not cover the design of functional elements and standard features. Although copyright law provides automatic protection to all original architectural plans, the limitation is that copyright only protects the expression of ideas but not the ideas themselves. It can be argued that architectural drawings and design, including models are recognised categories of artistic works which are protected under the copyright law. This research investigates to what extent copyrights protect the rights and interests of the designers on architectural works and design.

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The evolutionary history of P. vulgaris is important to those working on its genetic resources, but is not reflected in its infraspecific taxonomy. Genetic isolation of wild populations between and also within Middle and South America has resulted in morphological and molecular differentiation. Populations from northern and southern ends of the range are assigned to different gene pools, though intermediates occur in intervening areas. Chloroplast haplotypes suggest three distinct lineages of wild beans and several intercontinental dispersals. The species was domesticated independently in both Middle and South America, probably several times in Middle America. This, together with further differentiation under human selection, has produced distinct races among domesticated beans. The informal categories of wild versus domesticated, gene pool, and race convey the evolutionary picture more clearly than the formal categories provided by the Codes of Nomenclature for wild or cultivated plants.

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Objective: To determine whether consumption of five portions of fruit and vegetables per day reduces the enhancement of oxidative stress induced by consumption of fish oil. Subjects: A total of 18 free-living healthy smoking volunteers, aged 18-63 y, were recruited by posters and e-mail in The University of Reading, and by leaflets in local shops. Design: A prospective study. Setting: Hugh Sinclair Unit of Human Nutrition, School of Food Biosciences, The University of Reading, Whiteknights PO Box 226, Reading RG6 6AP, UK. Intervention: All subjects consumed a daily supplement of 4 x 1 g fish oil capsules for 9 weeks. After 3 weeks, they consumed an additional five portions of fruits and vegetables per day, and then they returned to their normal diet for the last 3 weeks of the study. Fasting blood samples were taken at the ends of weeks 0, 3, 6 and 9. Results: The plasma concentrations of ascorbic acid, lutein, beta-cryptoxanthin, alpha-carotene and beta-carotene all significantly increased when fruit and vegetable intake was enhanced (P<0.05). Plasma concentrations of α-tocopherol, retinol and uric acid did not change significantly during the period of increased fruit and vegetable consumption. Plasma oxidative stability, assessed by the oxygen radical absorbance capacity (ORAC) assay, also increased from weeks 3-6 (P<0.001) but not in association with increases in measured antioxidants. Lag phase before oxidation of low-density lipoprotein (LDL) significantly decreased in the first 3 weeks of the study, reflecting the incorporation of EPA and DHA into LDL (P<0.0001). Subsequent enhanced fruit and vegetable consumption significantly reduced the susceptibility of LDL to oxidation (P<0.005). Conclusion: Fish oil reduced the oxidative stability of plasma and LDL, but the effects were partially offset by the increased consumption of fruit and vegetables.

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Listeners were asked to identify modified recordings of the words "sir" and "stir," which were spoken by an adult male British-English speaker. Steps along a continuum between the words were obtained by a pointwise interpolation of their temporal-envelopes. These test words were embedded in a longer "context" utterance, and played with different amounts of reverberation. Increasing only the test-word's reverberation shifts the listener's category boundary so that more "sir"-identifications are made. This effect reduces when the context's reverberation is also increased, indicating perceptual compensation that is informed by the context. Experiment I finds that compensation is more prominent in rapid speech, that it varies between rooms, that it is more prominent when the test-word's reverberation is high, and that it increases with the context's reverberation. Further experiments show that compensation persists when the room is switched between the context and the test word, when presentation is monaural, and when the context is reversed. However, compensation reduces when the context's reverberation pattern is reversed, as well as when noise-versions of the context are used. "Tails" that reverberation introduces at the ends of sounds and at spectral transitions may inform the compensation mechanism about the amount of reflected sound in the signal. (c) 2005 Acoustical Society of America.

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In an ideal "reverberant" room, the energy of the impulse responses decays smoothly, at a constant rate of dB/s, so that gradually-decaying tails are added at the ends of sounds. Conversely, a single echo gives a flat energy-decay up to the echo's arrival time, which then drops abruptly, so that sounds with only echoes lack the decaying-tail feature of reverberation. The perceptual effects of these types of reflection pattern were measured with test-words from a continuum of steps between "sir" and "stir", which were each embedded in a carrier phrase. When the proportion of reflected sound in test-words is increased, to a level above the amount in the carrier, the test words sound more like "sir". However, when the proportion of reflected sound in the carrier is also increased, to match the amount in the test word, there can be a perceptual compensation where test words sound more like "stir" again. A reference condition used real-room reverberation from recordings at different source to receiver distances. In a synthetic-reverberation condition, the reflection pattern was from a "colorless" impulse response, comprising exponentially-decaying reflections that were spaced at intervals. In a synthetic-echo condition, the reflection pattern was obtained from the synthetic reverberation by removing the intervals between reflections before delaying the resulting cluster relative to the direct sound. Compensation occurred in the reference condition and in different types of synthetic reverberation, but not in synthetic-echo conditions. This result indicates that the presence of tails from reverberation informs the compensation mechanism.

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Starting point for these outputs is a large scale research project in collaboration with the Zurich University for the Arts and the Kunstmuseum Thun, looking at a redefinition of Social Sculpture (Joseph Beuys/ Bazon Brock, 1970) as a functional device re-deployed to expand the art discourse into a societal discourse. Although Beuys‘ version of a social sculpture involved notions of abstruse mysticism and reformulations of a national identity these were never-the less part of a social transformation that shifted and re-arranged power relations. Following Laclau and Mouffe in their contention that democray is a fundamentally antagonistic process and contesting Grant Kester’s understanding of a ethically based relational practice, this work is alignes itself with Hirschhorn’s claim to an aesthetic practice within communities, following the possibility to view a socially based practice from both ends of the ethics debate, whereby ethical aspects fuels the aethetic to “create situations that are beautiful because they are ethical and shocking because they are ethical, thus in turn aesthetic because they are ethical” (O’Donnell). This project sets out to engage in activities which interact with surrounding communities and evoce new imaginations of site, thereby understanding site as a catalysts for subjective emergences. Performance is tested as a site for social practice. Archival research into local audio/visual resources, such as the Swiss Radio Archive, the Swiss Military Film Archives and zoological film archives of the Basel Zoo, was instrumental to the navigation of this work, under theme of crisis, catastrophy, landscape, fallout, in order to create a visual language for an active performance site. Commissioned by the Kunstmuseum Thun in collaboration with the University for the Arts in Zurich as part of a year long exhibition programme, (other artists are Jeanne Van Heeswijk (NL) and San Keller (CH), ) this project brings together a series of different works in a new performace installation. The performance process includes a performance workshop with 30 school children from local Swiss schools and their teachers, which was conducted publicly in the museum spaces. It enabled the children to engage with an unexpected set of tribal and animalistic behaviours, looking at situations of flight and rescue, resulting in a large performance choreography orchestration without an apparent conductor, it includes a collaboration with renowned Swiss zoologist, Prof Klaus Zuberbühler(University of St Andrews) and the Colonal General Haldimann commander of the military base in Thun. The installation included 2 static video images, shot in an around spectacular local cave site (Beatus Caves) including 3 children. The project will culminate in an edited edition of the Oncurating Journal, (issue no, tbc, in 2012) including interviews and essays from project collaborators. (Army Commander General, Thun, Jörg Hess, performance script, Timothy Long, and others)

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We study by Langevin molecular dynamics simulations systematically the influence of polydispersity in the particle size, and subsequently in the dipole moment, on the physical properties of ferrofluids. The polydispersity is in a first approximation modeled by a bidisperse system that consists of small and large particles at different ratios of their volume fractions. In the first part of our investigations the total volume fraction of the system is fixed, and the volume fraction phi(L) of the large particles is varied. The initial susceptibility chi and magnetization curve of the systems show a strong dependence on the value of phi(L). With the increase of phi(L), the magnetization M of the system has a much faster increment at weak fields, and thus leads to a larger chi. We performed a cluster analysis that indicates that this is due to the aggregation of the large particles in the systems. The average size of these clusters increases with increasing phi(L). In the second part of our investigations, we fixed the volume fraction of the large particles, and increased the volume fraction phi(S) of the small particles in order to study their influence on the chain formation of the large ones. We found that the average aggregate size formed by large particles decreases when phi(S) is increased, demonstrating a significant effect of the small particles on the structural properties of the system. A topological analysis of the structure reveals that the majority of the small particles remain nonaggregated. Only a small number of them are attracted to the ends of the chains formed by large particles.

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A basic data requirement of a river flood inundation model is a Digital Terrain Model (DTM) of the reach being studied. The scale at which modeling is required determines the accuracy required of the DTM. For modeling floods in urban areas, a high resolution DTM such as that produced by airborne LiDAR (Light Detection And Ranging) is most useful, and large parts of many developed countries have now been mapped using LiDAR. In remoter areas, it is possible to model flooding on a larger scale using a lower resolution DTM, and in the near future the DTM of choice is likely to be that derived from the TanDEM-X Digital Elevation Model (DEM). A variable-resolution global DTM obtained by combining existing high and low resolution data sets would be useful for modeling flood water dynamics globally, at high resolution wherever possible and at lower resolution over larger rivers in remote areas. A further important data resource used in flood modeling is the flood extent, commonly derived from Synthetic Aperture Radar (SAR) images. Flood extents become more useful if they are intersected with the DTM, when water level observations (WLOs) at the flood boundary can be estimated at various points along the river reach. To illustrate the utility of such a global DTM, two examples of recent research involving WLOs at opposite ends of the spatial scale are discussed. The first requires high resolution spatial data, and involves the assimilation of WLOs from a real sequence of high resolution SAR images into a flood model to update the model state with observations over time, and to estimate river discharge and model parameters, including river bathymetry and friction. The results indicate the feasibility of such an Earth Observation-based flood forecasting system. The second example is at a larger scale, and uses SAR-derived WLOs to improve the lower-resolution TanDEM-X DEM in the area covered by the flood extents. The resulting reduction in random height error is significant.

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The most damaging winds in a severe extratropical cyclone often occur just ahead of the evaporating ends of cloud filaments emanating from the so-called cloud head. These winds are associated with low-level jets (LLJs), sometimes occurring just above the boundary layer. The question then arises as to how the high momentum is transferred to the surface. An opportunity to address this question arose when the severe ‘St Jude's Day’ windstorm travelled across southern England on 28 October 2013. We have carried out a mesoanalysis of a network of 1 min resolution automatic weather stations and high-resolution Doppler radar scans from the sensitive S-band Chilbolton Advanced Meteorological Radar (CAMRa), along with satellite and radar network imagery and numerical weather prediction products. We show that, although the damaging winds occurred in a relatively dry region of the cyclone, there was evidence within the LLJ of abundant precipitation residues from shallow convective clouds that were evaporating in a localized region of descent. We find that pockets of high momentum were transported towards the surface by the few remaining actively precipitating convective clouds within the LLJ and also by precipitation-free convection in the boundary layer that was able to entrain evaporatively cooled air from the LLJ. The boundary-layer convection was organized in along-wind rolls separated by 500 to about 3000 m, the spacing varying according to the vertical extent of the convection. The spacing was greatest where the strongest winds penetrated to the surface. A run with a medium-resolution version of the Weather Research and Forecasting (WRF) model was able to reproduce the properties of the observed LLJ. It confirmed the LLJ to be a sting jet, which descended over the leading edge of a weaker cold-conveyor-belt jet.

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In A Compendium of the Characteristics of Categories (Padārthadharmasaṃgraha) the classical Vaiśeṣika philosopher Praśastapāda (6th c. CE) presents an innovative metaphysics of the self. This article examines the defining metaphysical and axiological features of this conception of self and the dualist categorial schema in which it is located. It shows how this idea of the self, as a reflexive and ethical being, grounds a multinaturalist view of natural order and offers a conception of agency that claims to account for all the reflexive features of human mental and bodily life. Finally, it discusses the ends of self’s reflexivity and of human life as a return to the true self. It argues that at the heart of Praśastapāda’s metaphysics of self is the idea that ethics is metaphysics, and that epistemic practice is ethical practice.

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Utilising supramolecular pi-pi stacking interactions to drive miscibility in two-component polymer blends offers a novel approach to producing materials with unique properties. We report in this paper the preparation of a supramolecular polymer network that exploits this principle. A low molecular weight polydiimide which contains multiple pi-electron-poor receptor sites along its backbone forms homogeneous films with a siloxane polymer that features pi-electron-rich pyrenyl end-groups. Compatibility results from a complexation process that involves chain-folding of the polydiimide to create an optimum binding site for the pi-electron-rich chain ends of the polysiloxane. These complementary pi-electron-rich and -poor receptors exhibit rapid and reversible complexation behaviour in solution, and healable characteristics in the solid state in response to temperature. A mechanism is proposed for this thermoreversible healing behaviour that involves disruption of the intermolecular pi-pi stacking cross-links as the temperature of the supramolecular film is increased. The low T-g siloxane component can then flow and as the temperature of the blend is decreased, pi-pi stacking interactions drive formation of a new network and so lead to good damage-recovery characteristics of the two-component blend.