758 resultados para the lived
Resumo:
It is difficult, even excruciating, to imagine the staggering descent from high optimism to despondency experienced by many African Americans who lived between emancipation and the dawn of the twentieth century. For historians living in the post–civil rights era, recapturing the scale, velocity, and brutality of that dramatic fall has been hampered by two conceptual problems. The first of these, undergirded by prominent trends in the formerly “new” social history, is a widely shared enthusiasm for illuminating those hidden corners of daily life where men and women on the receiving end of Jim Crow continued to wield a degree of control. “Agency” has been the buzzword for a generation of scholarship that emphasizes the staying power and persistence of black Southerners in the face of relentless assaults on their social and economic status, their civil rights, and even, at times, their collective existence. This is, in many ways, an understandable reaction to an earlier consensus that relegated black historical initiative to the margins of a national fable cleansed of unseemly violence and sharp social conflict, but it can also be problematic.
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The `hot Jupiters' that abound in lists of known extrasolar planets are thought to have formed far from their host stars, but migrate inwards through interactions with the proto-planetary disk from which they were born, or by an alternative mechanism such as planet-planet scattering. The hot Jupiters closest to their parent stars, at orbital distances of only ~0.02 astronomical units, have strong tidal interactions, and systems such as OGLE-TR-56 have been suggested as tests of tidal dissipation theory. Here we report the discovery of planet WASP-18b with an orbital period of 0.94days and a mass of ten Jupiter masses (10MJup), resulting in a tidal interaction an order of magnitude stronger than that of planet OGLE-TR-56b. Under the assumption that the tidal-dissipation parameter Q of the host star is of the order of 106, as measured for Solar System bodies and binary stars and as often applied to extrasolar planets, WASP-18b will be spiralling inwards on a timescale less than a thousandth that of the lifetime of its host star. Therefore either WASP-18 is in a rare, exceptionally short-lived state, or the tidal dissipation in this system (and possibly other hot-Jupiter systems) must be much weaker than in the Solar System.
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Near-infrared emitting complexes of Nd(III), Er(III), and Yb(III) based on hexacoordinate lanthanide ions with an aryl functionalized imidodiphosphinate ligand, tpip, have been synthesized and fully characterized. Three tpip ligands form a shell around the lanthanide with the ligand coordinating via the two oxygens leading to neutral complexes, Ln(tpip)(3). In the X-ray crystal structures of Er(III) and Nd(III) complexes there is evidence of CH-pi interactions between the phenyl groups. Photophysical investigations of solution samples of the complexes demonstrate that all complexes exhibit relatively long luminescence lifetimes in nondeuteurated solvents. Luminescence studies of powder samples have also been recorded for examination of the properties of NIR complexes in the solid state for potential material applications. The results underline the effective shielding of the lanthanide by the twelve phenyl groups of the tpip ligands and the reduction of high-energy vibrations in close proximity to the lanthanide, both features important in the design of NIR emitting lanthanide complexes.
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This article compares experiences of shared schooling in societies with 2 distinctive traits: first, a history of intercommunity conflict and isolation; and second, a segregated school system. Drawing on Parekh’s (2006) reconceptualisation of multiculturalism, this article analyses issues arising from experiences of intercommunity contact in shared schools in Quebec and Northern Ireland—in one case, bringing Anglophones and Francophones together and, in the other, Protestants and Catholics. Research data from both contexts is drawn upon to reflect on how this experience is lived. The metaphor of a journey is used to capture what it represents for those involved. A need to clarify, recognize, and exploit the potential of shared schooling for the transformation of divided societies is identified.
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Introduction
Much has been written about the impact of conflict on the physical nature of cities; most obviously perhaps the damage, destruction, defensive construction and spatial reconfigurations that evolve in times of conflict. Set within the context of Belfast, Northern Ireland, this paper will focus on three areas. First, a closer reading of the long-term physical impact of conflict, in particular, the spatial forms and practices that persist conceptually and culturally, and/or resist re-conceptualisation. Secondly, the effect of conflict on the nature of architectural practice itself, considering whether issues such as appointment and procurement impacted on architectural expectation and the context of operation. Thirdly, the effect of conflict on people, in particular in relation to creativity and hence the psyche of practice itself. This section will also identify the conditions that undermine or support design quality and creativity not only within times of conflict but also as society evolves out of the shadow space. 1
Twelve years on from the Peace Agreement,2 it may seem remarkable from an external perspective that Northern Ireland still needs to be reflecting on its troubled past. But the immediate post-conflict phase offered the communities of Northern Ireland place and time to experience ‘normal life’, begin to reconcile themselves to the hurt they experienced and start to reconfigure their relationships to one another. Indeed, it has often been expressed that probing the issues too much, at too early a phase, might in fact ‘Open old wounds without resolving anything’ and/or ‘Destabilise the already fragile political system.’3 This tendency not to deliberate or be too probing is therefore understandable and might be the reason why, for example, Northern Ireland's first Architecture and Built Environment policy, published in June, 2006, contains only one routine reference to ‘the Troubles’.
Clearly, however, there is a time in the development of a healthy, functioning society, when in order effectively to plan its future, it must also carry out a closer reading and deeper understanding of its past. As Maya Angelou puts it, ‘History, despite its wrenching pain/ Cannot be unlived, and if faced/ With courage, need not be lived again.’4
Increasingly, those within the creative arts sector and the built environment professions are showing interest in carrying out that closer reading, teasing out issues around conflict. This was led in part by the recent publication of the Troubles Archive by the Arts Council of Northern Ireland.5 Those involved in the academic or professional development of future generations of architects are also concerned about the relevance of a post-conflict condition. As a profession, if architects purport to be concerned with context, then the almost tangible socio-political circumstances and legacy of Northern Ireland does inevitably require direct eye contact. This paper therefore aims to bring the relationship between conflict and architectural practice in Northern Ireland into sharp focus, not to constrain or dull creative practice but to heighten its potential.
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In 1700 few Irishwomen were literate. Most lived in a rural environment, rarely encountered a book or a play or ventured much beyond their own domestic space. By 1960 literacy was universal, all Irishwomen attended primary school, had access to a variety of books, magazines, newspapers and other forms of popular media and the wider world was now part of their every-day life. This study seeks to examine the cultural encounters and exchanges inherent in this transformation. It analyses reading and popular and consumer culture as sites of negotiation of gender roles. This is not an exhaustive treatment of the theme but focusses on three key points of cultural encounter: the Enlightenment, emigration and modernism. The writings and intellectual discourse generated by the Enlightenment was one of the most influential forces shaping western society. It set the agenda for scientific, political and social thought for the eighteenth and nineteenth centuries. The migration of peoples to north America was another key historical marker in the development of the modern world. Emigration altered and shaped American society as well as the lives of those who remained behind. By the twentieth century, aesthetic modernism suspicious of enlightenment rationalism and determined to produce new cultural forms developed in a complex relationship with the forces of industrialisation, urbanisation and social change. This study analyses the impact of these three key forces in Western culture on changing roles and perceptions of Irish women from 1700 to 1960.
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In this paper I examine the transformation that the skin has undergone over the centuries. This change in conception in the skin whereby the skin is considered less a boundary space and more akin to a milieu, a meeting place for the other senses, allows me to posit the performative body as one engaged in a haptic condition, as a body in intimately lived-in spaces with tactile relations. A shift from the optical towards the haptic, in which the all- encompassing god-like view of traditional performance environments becomes replaced by a more haptic condition, as can be exemplified in performances in dispersed environments, posits the body skinned as a fragile body that wants to favour the incomplete and the fragmented. The body skinned is a body initiated by the observed and the perspectival, but it is nourished by means of the local and the embodied. It is a body that, like the skin, is more akin to a meeting place of, and for, the other senses, as well as for senses of the others. Most clearly, the body skinned brings to the fore a potential of being ‘connected a little less’. It is a body that embraces notions of the incomplete, of glances, and of fantasies, and in this light may be a body more ideally suited to environments that purposely displace performative action, such as found in network performance environments.
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In this paper we reflect on the performer-instrument relationship by turning towards the thinking practices of the French philosopher Maurice Merleau-Ponty (1908-1961). Merleau-Ponty's phenomenological idea of the body as being at the centre of the world highlights an embodied position in the world and bestows significance onto the body as a whole, onto the body as a lived body. In order to better understand this two-way relationship of instrument and performer, we introduce the notion of the performative layer, which emerges through strategies for dealing with discontinuities, breakdowns and the unexpected in network performance.
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SuWt 2 is a planetary nebula (PN) consisting of a bright ionized thin ring seen nearly edge-on, with much fainter bipolar lobes extending perpendicularly to the ring. It has a bright (12th magnitude) central star, too cool to ionize the PN, which we discovered in the early 1990s to be an eclipsing binary. Although it was anticipated that there would also be an optically faint, hot, ionizing star in the system, a spectrum from the International Ultraviolet Explorer (IUE) did not reveal a UV source. We present extensive ground-based photometry and spectroscopy of the central binary collected over the ensuing two decades, resulting in the determination that the orbital period of the eclipsing pair is 4.9 days, and that it consists of two nearly identical A1 V stars, each of mass ~2.7 M sun. The physical parameters of the A stars, combined with evolutionary tracks, show that both are in the short-lived "blue-hook" evolutionary phase that occurs between the main sequence and the Hertzsprung gap, and that the age of the system is about 520 Myr. One puzzle is that the stars' rotational velocities are different from each other, and considerably slower than synchronous with the orbital period. It is possible that the center-of-mass velocity of the eclipsing pair is varying with time, suggesting that there is an unseen third orbiting body in the system. We propose a scenario in which the system began as a hierarchical triple, consisting of a ~2.9 M sun star orbiting the close pair of A stars. Upon reaching the asymptotic giant branch stage, the primary engulfed the pair into a common envelope, leading to a rapid contraction of the orbit and catastrophic ejection of the envelope into the orbital plane. In this picture, the exposed core of the initial primary is now a white dwarf of ~0.7 M sun, orbiting the eclipsing pair, which has already cooled below the detectability possible by IUE at our derived distance of 2.3 kpc and a reddening of E(B - V) = 0.40. The SuWt 2 system may be destined to perish as a Type Ia supernova.
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Resonance Raman (RR) spectroscopy has been used to probe the interaction between dipyridophenazine (dppz) complexes of ruthenium(II), [Ru(L)(2)(dppz)](2+) (L = 1,10-phenanthroline (1) and 2,2-bipyridyl (2)), and calf-thymus DNA. Ground electronic state RR spectra at selected probe wavelengths reveal enhancement patterns which reflect perturbation of the dppz-centered electronic transitions in the UV-vis spectra in the presence of DNA. Comparison of the RR spectra recorded of the short-lived MLCT excited states of both complexes in aqueous solution with those of the longer-lived states of the complexes in the DNA environment reveals changes to excited state modes, suggesting perturbation of electronic transitions of the dppz ligand in the excited state as a result of intercalation. The most prominent feature, at 1526 cm(-1), appears in the spectra of both 1 and 2 and is a convenient marker band for intercalation. For 1, the excited state studies have been extended to the A and A enantiomers. The marker band appears at the same frequency for both but with different relative intensities. This is interpreted as reflecting the distinctive response of the enantiomers to the chiral environment of the DNA binding sites. The results, together with some analogous data for other potentially intercalating complexes, are considered in relation to the more general application of time-resolved RR spectroscopy for investigation of intercalative interactions of photoexcited metal complexes with DNA.
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Time-resolved resonance Raman spectroscopy of the lowest energy excited state of the 4,4'-bipyridyl ligand-bridged complex, [(CO)(5)W(L)W(CO5] (1), and Raman spectroscopy of electrochemically reduced 1, both give bands characteristic of the the L(.-) species. This confirms that the ligand L is negatively charged in the lowest energy exicited state which is therefore metal-ligand charge transfer (MLCT) in character. Raman spectra of the radical anion of 1 excited in the far red (800 nm) exhibited a band near 2050 cm(-1) due to a vco symmetric CO stretching mode, compared to the corresponding band at 2070 cm(-1) in the spectrum of the parent, uncharged complex. The lower vco in the reduced complex supports the recent finding by time-resolved IR spectroscopy of a similar frequency decrease for nu(CO) in the longest lived (MLCT) excited state of 1 which was attributed to electron/hole localisation in this state on the IR time scale.
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Raman spectroscopy is a noninvasive, nondestructive tool for capturing multiplexed biochemical information across diverse molecular species including proteins, lipids, DNA, and mineralizations. Based on light scattering from molecules, cells, and tissues, it is possible to detect molecular fingerprints and discriminate between subtly different members of each biochemical class. Raman spectroscopy is ideal for detecting perturbations from the expected molecular structure such as those occurring during senescence and the modification of long-lived proteins by metabolic intermediates as we age. Here, we describe the sample preparation, data acquisition, signal processing, data analysis and interpretation involved in using Raman spectroscopy for detecting age-related protein modifications in complex biological tissues.
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As a diagnostic of high-intensity laser interactions (> 10(19) W cm(-2)), the detection of radioactive isotopes is regularly used for the characterization of proton, neutron, ion, and photon beams. This involves sample removal from the interaction chamber and time consuming post shot analysis using NaI coincidence counting or Ge detectors. This letter describes the use of in situ detectors to measure laser-driven (p,n) reactions in Al-27 as an almost real-time diagnostic for proton acceleration. The produced Si-27 isotope decays with a 4.16 s half-life by the predominantly beta+ emission, producing a strong 511 keV annihilation peak. (c) 2006 American Institute of Physics.
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Positron emission tomography (PET) is a powerful diagnostic/imaging technique requiring the production of the short-lived positron emitting isotopes C-11, N-13, O-15 and F-18 by proton irradiation of natural/enriched targets using cyclotrons. The development of PET has been hampered due to the size and shielding requirements of nuclear installations. Recent results show that when an intense laser beam interacts with solid targets, megaelectronvolt (MeV) protons capable of producing PET isotopes are generated. This report describes how to generate intense PET sources of C-11 and F-18 using a petawatt laser beam. The work describing the laser production of F-18 through a (p,n) O-18 reaction, and the subsequent synthesis of 2-[F-18] is reported for the first time. The potential for developing compact laser technology for this purpose is discussed.
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A novel FMRFamide-related heptapeptide, Lys-Pro-Asn-Phe-Ile-Arg-Phe-NH2 (KPNFIRFamide), was isolated and characterized from acid ethanol extracts of the free-living nematode, Panagrellus redivivus. Whole-worm extracts contained greater than or equal to 9 pmol KPNFIRFamide/g wet weight. A synthetic replicate of this peptide induced a rapid relaxation of tone and inhibited spontaneous contractility in isolated innervated and denervated body-wall muscle strips of the parasitic nematode, Ascaris suum. KPNFIRFamide (0.1 nM) induced measurable relaxations in 50% of the muscle preparations examined. Concentrations greater than or equal to 0.3 nM induced relaxation in 100% of muscle preparations examined. The relaxation was short-lived at concentrations of peptide greater than or equal to 1 mu M and displayed a profile typical of receptor desensitization. These data suggest the occurrence of a closely related peptide in A. suum and add further evidence to the concept of primary structural conservation of FaRPs within the nematodes.