39 resultados para STARK LADDERS


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The carbon-to-oxygen ratio (C/O) in a planet provides critical information about its primordial origins and subsequent evolution. A primordial C/O greater than 0.8 causes a carbide-dominated interior, as opposed to the silicate-dominated composition found on Earth; the atmosphere can also differ from those in the Solar System. The solar C/O is 0.54 (ref. 3). Here we report an analysis of dayside multi-wavelength photometry of the transiting hot-Jupiter WASP-12b (ref. 6) that reveals C/O>=1 in its atmosphere. The atmosphere is abundant in CO. It is depleted in water vapour and enhanced in methane, each by more than two orders of magnitude compared to a solar-abundance chemical-equilibrium model at the expected temperatures. We also find that the extremely irradiated atmosphere (T>2,500K) of WASP-12b lacks a prominent thermal inversion (or stratosphere) and has very efficient day-night energy circulation. The absence of a strong thermal inversion is in stark contrast to theoretical predictions for the most highly irradiated hot-Jupiter atmospheres.

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The reactivity of four different monoclonal antibodies (MAbs) with populations of Bacteroides fragilis NCTC 9343, enriched by density gradient centrifugation for a large capsule, small capsule and electron-dense layer (EDL) only visible by electronmicroscopy, was examined. The MAbs reacted strongly with polysaccharides present in both the large capsule- and EDL-enriched populations but not in the small capsule-enriched populations. The pattern of labelling was determined by immunoblotting, immunofluorescence and immuno-electronmicroscopy, and flow cytometry. The MAbs labelled cell membrane-associated epitopes in the large capsule- and EDL-enriched populations and cell-free material in the EDL population. By immunoblotting, ladders of repeating polysaccharide subunits were evident in the EDL population but not in the large capsule population. The proportion of cells labelled within each population was determined by flow cytometry. The reactivity of another MAb with the small capsule population was confirmed by flow cytometry. A qualitative indication of epitope expression was obtained by examination of the flow cytometric profiles. Differential expression of the same saccharide epitope was observed both between and within structurally distinct B. fragilis populations. The MAbs were species-specific and cross-reacted with several recent clinical isolates. These polysaccharides may be relevant to the virulence of B. fragilis.

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The International Olympic Committee (IOC) declares environmental protection to be the third dimension of the Olympic movement. That, in effect, means that nations wishing to host the Games have to present themselves as reliable practitioners of environmental sustainability (ES) in their applications. The greening of sports mega-events, and the hosting of Olympic Games in particular, is now reasonably well established. Yet evidence from the first decade of environmentally-conscious Olympics points to diverging patterns of achievement in the operationalisation of the IOC’s ‘third pillar’. As is now common knowledge, for example, Sydney 2000 was the first ‘Green Olympics’ in the history of the Games; yet four years later, Athens provided a stark contrast, and was the subject of highly critical assessment reports by environmental organisations. Yet Athens has not stopped the Bid Committee for the Beijing 2008 Games claiming that it would ‘leave the greatest Olympic Games environmental legacy ever’ (UNEP 2007: 26), while the London 2012 promotes the concept of the ‘One Planet Olympics’.

In this context and in light of the current global economic crisis, can we claim that London 2012 has the capacity to fulfil its environmental ambitions? This question is adopted in continuity with similar framed questions that have been posed in relation to the most recent Olympics and it is tackled by adopting an investigative model that is placed within discourses of ‘reflexive modernisation’.

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Essential genes are absolutely required for the survival of an organism. The identification of essential genes, besides being one of the most fundamental questions in biology, is also of interest for the emerging science of synthetic biology and for the development of novel antimicrobials. New antimicrobial therapies are desperately needed to treat multidrug-resistant pathogens, such as members of the Burkholderia cepacia complex.

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Whilst Muriel Rukeyser's poetic affinity with Walt Whitman is generally acknowledged, the close relation of her work and poetic sensibility to the thought and writing of Herman Melville has somehow gone relatively unnoticed, and almost wholly unexamined. In 1918, Van Wyck Brooks called for the creation of a usable past that would energize America by recasting its cultural tradition. His plea addressed the need to rebuild a national heritage via the rediscovery of culturally “great” figures. By the late 1930s, many scholars and writers had answered the call, and the new discipline of American studies was beginning to take shape, aided by a reclamation of one of the country's greatest, most neglected, writers – Herman Melville. This was also the period in which Rukeyser “came of age”; a time when political and international conflicts and economic crises generated both the stark, documentary representation of present social realities and the drive to retrieve or reconstruct a more golden age that might mobilize a dislocated nation. The following article examines the importance of Melville to Rukeyser's work, and situates her within the “Melville revival” as an important figure in the movement throughout the first half of the twentieth century to reconstruct an American cultural character.

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Radical anions of 1-bromo-4-nitrobenzene (p-BrC6H4NO2) are shown to be reactive in the room temperature ionic liquid N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, ([C(4)mPyrr][NTf2]), by means of voltammetric measurements. In particular, they are shown to react via a DISP type mechanism such that the electrolysis of p-BrC6H4NO2 occurs consuming between one and two electrons per reactant molecule, leading to the formation of the nitrobenzene radical anion and bromide ions. This behaviour is a stark contrast to that in conventional non-aqueous solvents such as acetonitrile, dimethyl sulfoxide or N,N-dimethylformamide, which suggests that the ionic solvent promotes the reactivity of the radical anion, probably via stabilisation of the charged products.

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We report here the first systematic study of the effect of impurities and additives (e.g., water, chloride, and cosolvents) on the physical properties of room-temperature ionic liquids. Remarkably, it was discovered that the viscosity of mixtures was dependent mainly on the mole fraction of added molecular solvents and only to a lesser extent upon their identity, allowing viscosity changes during the course of a reaction to be entirely predictable. While the addition of such molecular solvents decreases the viscosity and density, chloride impurities, arising from the preparation of the ionic liquids, increase viscosity dramatically. The commonly used methods of preparation were validated with respect to chloride impurity.

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Buffering of Lewis acidic chlorometallate ionic liquids is a useful tool to modify their properties for electrochemical and catalytic applications. Lewis acidic chlorogallate(iii) ionic liquids containing the 1-octyl-3-methylimidazolium cation, buffered with sodium chloride, were studied using (71)Ga NMR spectroscopy and cyclic voltammetry. All the studied Lewis acidic compositions (0.50 < χGaCl3 ≤ 0.75) could be buffered to mild or moderate acidity, but not to neutrality. Electrodeposition of gallium from such buffered systems was possible, yielding deposits of improved morphology over the unbuffered ionic liquids, due to the constant melt composition maintained by the buffer. These findings were in a stark contrast with older studies on chloroaluminate(iii) ionic liquids buffered with sodium chloride.

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Since 2008, Ireland has experienced the most severe economic and labour market crisis since the foundation of the State. These economic and labour market changes have had a stark impact on the standard of living across the Irish population. The rapid deterioration in the labour market, the rising level of household indebtedness and stringent austerity measures to plug the public finance deficit have had a widespread impact yet there is debate about where the heaviest burden has fallen and where the economic stress has been felt most. The paper analyses data from the Survey of Income and Living Conditions for the period 2004 to 2011. The aim of the paper is to develop and test a measure of economic stress, which will capture some of the aspects of the rapid change in economic fortunes on Irish households that are not picked up by income alone. This includes tapping into features of the recession such as debt problems, unsustainable housing costs, and other difficulties associated with managing on reduced household income in a period of uncertainty. In testing such a measure we examine trends over time from boom to bust in the Irish economy and consider how economic stress is distributed across different socio-economic groups. The paper explores the distribution and level of economic stress across income class groups, social classes and the life-course and tests the thesis of ‘middle class squeeze’.

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Approaches exploiting trait distribution extremes may be used to identify loci associated with common traits, but it is unknown whether these loci are generalizable to the broader population. In a genome-wide search for loci associated with the upper versus the lower 5th percentiles of body mass index, height and waist-to-hip ratio, as well as clinical classes of obesity, including up to 263,407 individuals of European ancestry, we identified 4 new loci (IGFBP4, H6PD, RSRC1 and PPP2R2A) influencing height detected in the distribution tails and 7 new loci (HNF4G, RPTOR, GNAT2, MRPS33P4, ADCY9, HS6ST3 and ZZZ3) for clinical classes of obesity. Further, we find a large overlap in genetic structure and the distribution of variants between traits based on extremes and the general population and little etiological heterogeneity between obesity subgroups.

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Coronary artery disease (CAD) is the commonest cause of death. Here, we report an association analysis in 63,746 CAD cases and 130,681 controls identifying 15 loci reaching genome-wide significance, taking the number of susceptibility loci for CAD to 46, and a further 104 independent variants (r(2)

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We study the dynamics of the entanglement spectrum, that is the time evolution of the eigenvalues of the reduced density matrices after a bipartition of a one-dimensional spin chain. Starting from the ground state of an initial Hamiltonian, the state of the system is evolved in time with a new Hamiltonian. We consider both instantaneous and quasi adiabatic quenches of the system Hamiltonian across a quantum phase transition. We analyse the Ising model that can be exactly solved and the XXZ for which we employ the time-dependent density matrix renormalisation group algorithm. Our results show once more a connection between the Schmidt gap, i.e. the difference of the two largest eigenvalues of the reduced density matrix and order parameters, in this case the spontaneous magnetisation.

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Dehydration of the airway surface liquid (ASL) and the resultant decline in function of the mucociliary escalator in cystic fibrosis airways is largely underpinned by the excessive flux of Na+ and water though ENaC. Proteolysis of the endogenous  and  subunits of epithelial sodium channels (ENaC) by channel activating proteases (CAPS) is the key regulatory mechanism for channel activation. Recent reports highlight that (1) CFTR (cystic fibrosis transmembrane conductance regulator) normally protects ENaC from the action of proteases and (2) a stark imbalance in proteases/protease inhibitor levels in CF airway cultures favour activation of normally inactive ENaC. The current study examines the potential therapeutic benefit of CAPS/ENaC inhibition in CF airways.
Our group has developed a panel of active-site directed affinity-based probes which target and inhibit trypsin-like proteases (potential CAPS); including the broad-spectrum inhibitor QUB-TL1. We have utilised this compound to interrogate the impact of trypsin-like protease inhibition on ENaC activity in differentiated primary airway epithelial cell cultures.
Electrophysiological data demonstrate QUB-TL1 selectively and irreversibly binds to extracellularly located trypsin-like proteases resulting in impaired ENaC-mediated Na+ transport. Visualisation of ENaC at the apical surface compartment of primary airway epithelial cells shows a large reduction in a low molecular weight (processed and active) form of ENaC, which was found to be abundant in untreated CF cultures. Consistent with the reduction in ENaC activity observed, QUB-TL1 treatment was subsequently shown to increase ASL height (performed in collaboration with Royal College of Surgeons in Ireland).
Our results are consistent with the hypothesis that targeting the CAPS-ENaC signalling axis may restore the depleted ASL seen in CF airways.

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This article explores the conformation in discourse of a verbal exchange and its subsequent mediatised and legal ramifications. The event concerns an allegedly racist insult directed by high profile English professional footballer John Terry towards another player, Anton Ferdinand, during a televised match in October 2011. The substance of Terry’s utterance, which included the noun phrase ‘fucking black cunt’, was found by a Chief Magistrate not to be a racist insult, although the fact that these actual words were framed within the utterance was not in dispute. The upshot of this ruling was that Terry was acquitted of a racially aggravated public order offence. A subsequent investigation by the regulatory commission of the English Football Association (FA) ruled, almost a year after the event, that Terry was guilty of racially abusing Ferdinand. Terry was banned for four matches and fined £220,000.

It is our contention that this event, played out in legal rulings, social media and print and broadcast media, constitutes a complex web of linguistic structures and strategies in discourse, and as such lends itself well to analysis with a broad range of tools from pragmatics, discourse analysis and cognitive linguistics. Amongst other things, such an analysis can help explain the seemingly anomalous - even contradictory - position adopted in the legal ruling with regard to the speech act status of ‘fucking black cunt’; namely, that the racist content of the utterance was not contested but that the speaker was found not to have issued a racist insult. Over its course, the article addresses this broader issue by making reference to the systemic-functional interpersonal function of language, particularly to the concepts of modality, polarity and modalisation. It also draws on models of verbal irony from linguistic pragmatics, notably from the theory of irony as echoic mention (c.f. Sperber and Wilson, 1981; Wilson and Sperber, 1992). Furthermore, the article makes use of the cognitive-linguistic framework, Text World Theory (c.f. Gavins, 2007; Werth, 1999) to examine the discourse positions occupied by key actors and adapts, from cognitive poetics, the theory of mind-modelling (c.f. Stockwell, 2009) to explore the conceptual means through which these actors discursively negotiate the event.

It is argued that the pragmatic and cognitive strategies that frame the entire incident go a long way towards mitigating the impact of so ostensibly stark an act of racial abuse. Moreover, it is suggested here that the reconciliation of Terry’s action was a result of the confluence of strategies of discourse with relations of power as embodied by the media, the law and perceptions of nationhood embraced by contemporary football culture. It is further proposed that the outcome of this episode, where the FA was put in the spotlight, and where both the conflict and its key antagonists were ‘intranational’, was strongly impelled by the institution of English football and its governing body both to reproduce and maintain social, cultural and ethnic cohesion and to avoid any sense that the event featured a discernable ‘out-group’.

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Infolge steigender Lebenserwartung sowie sinkender Geburtenraten wird das Durchschnittsalter der Bevölkerung in den meisten Industrienationen in den kommenden 50 Jahren stark ansteigen. Zur gleichen Zeit scheidet nach wie vor die Mehrzahl älterer Arbeitnehmer vor Erreichen der gesetzlichen Altersgrenze aus dem Arbeitsmarkt aus. Dies hat sowohl negative Auswirkungen auf die Finanzierbarkeit sozialer Sicherungssysteme als auch langfristig auf die Verfügbarkeit qualifizierter Arbeitnehmer am Arbeitsmarkt. Nationale Regierungen verfolgen daher gegenwärtig verschiedene Maßnahmen mit dem Ziel, die Arbeitsmarktbeteiligung älterer Arbeitnehmer zu erhöhen (OECD 2006). Diese Maßnahmen werden jedoch zum Teil durch die Strategien des betrieblichen Personalmanagements konterkariert, die oft noch jugendzentristisch ausgeprägt sind und ältere Mitarbeiter bei Einstellung, Beförderung, Weiterbildung sowie bei Arbeitsplatz- und Arbeitszeitgestaltung direkt oder indirekt benachteiligen (Bellmann et al. 2003).