19 resultados para Wyn, Dewi, 1784-1841


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Evidence is accumulating to suggest that some of the diverse functions associated with BRCA1 may relate to its ability to transcriptionally regulate key downstream target genes. Here, we identify S100A7 (psoriasin), S100A8, and S100A9, members of the S100A family of calcium-binding proteins, as novel BRCA1-repressed targets. We show that functional BRCA1 is required for repression of these family members and that a BRCA1 disease–associated mutation abrogates BRCA1-mediated repression of psoriasin. Furthermore, we show that BRCA1 and c-Myc form a complex on the psoriasin promoter and that BRCA1-mediated repression of psoriasin is dependent on functional c-Myc. Finally, we show that psoriasin expression is induced by the topoisomerase IIA poison, etoposide, in the absence of functional BRCA1 and increased psoriasin expression enhances cellular sensitivity to this chemotherapeutic agent. Therefore, we identified a novel transcriptional mechanism that is likely to contribute to BRCA1-mediated resistance to etoposide.

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Aggressive interactions between animals are often settled by the use of repeated signals that reduce the risk of injury from combat but are expected to be costly. The accumulation of lactic acid and the depletion of energy stores may constrain activity rates during and after fights and thus represent significant costs of signalling. We tested this by analysing the concentrations of lactate and glucose in the haemolymph of hermit crabs following agonistic interactions over the ownership of the gastropod shells that they inhabit. Attackers and defenders play distinct roles of sender and receiver that are fixed for the course of the encounter. Attackers perform bouts of 'shell rapping', which vary in vigour between attackers and during the course of the encounter, and are a key predictor of victory. In contrast to the agonistic behaviour of other species, we can quantify the vigour of fighting. We demonstrate, to our knowledge for the first time, an association between the vigour of aggressive activity and a proximate cost of signalling. We show that the lactate concentration in attackers increases with the amount of shell rapping, and that this appears to constrain the vigour of subsequent rapping. Furthermore, attackers, but not defenders, give up when the concentration of lactate is high. Glucose levels in attackers also increase with the amount of rapping they perform, but do not appear to influence their decision to give up. Defenders are more likely to lose when they have particularly low levels of glucose. We conclude that the two roles use different decision rules during these encounters.

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We present wide-field imaging of the 2007 outburst of Comet 17P/Holmes obtained serendipitously by SuperWASP-North on 17 nights over a 42-night period beginning on the night (2007 October 22-23) immediately prior to the outburst. Photometry of 17P's unresolved coma in SuperWASP data taken on the first night of the outburst is consistent with exponential brightening, suggesting that the rapid increase in the scattering cross-section of the coma could be largely due to the progressive fragmentation of ejected material produced on a very short time-scale at the time of the initial outburst, with fragmentation time-scales decreasing from tfrag ~ 2 × 103 to ~1 × 103 s over our observing period. Analysis of the expansion of 17P's coma reveals a velocity gradient suggesting that the outer coma was dominated by material ejected in an instantaneous, explosive manner. We find an expansion velocity at the edge of the dust coma of vexp = 0.55 +/- 0.02 kms -1 and a likely outburst date of t0 = 2007 October 23.3 +/- 0.3, consistent with our finding that the comet remained below SuperWASP's detection limit of mV ~ 15mag until at least 2007 October 23.3. Modelling of 17P's gas coma indicates that its outer edge, which was observed to extend past the outer dust coma, is best explained with a single pulse of gas production, consistent with our conclusions concerning the production of the outer dust coma.

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When the Bonn stage was closed after the death of Elector Max Friedrich in 1784, the director of its theatre company, Gustav Friedrich Wilhelm Großmann, decided to leave the city to further his career elsewhere in the Rhinelands. During the next few years, he was kept informed about developments in Bonn by two of his erstwhile colleagues, Christian Gottlob Neefe and Nikolaus Simrock, whose correspondence paints a vivid picture of musical life in the city during the later 1780s. The new Elector, Maximilian Franz, permitted a visiting troupe to perform during Carnival each year, but repeatedly delayed the decision to re-establish a resident troupe. In 1787 Christoph Brandt, a singer in the Bonn Hofkapelle, attempted a home-grown initiative, perhaps to test the market for a new permanent company. Although this failed almost immediately, a single, well-attended public rehearsal of Monsigny’s Le Déserteur was given, in which Johann van Beethoven made what was probably his last stage appearance. In a letter dated 14 May 1787, Simrock rated his performance ‘zimlich gut’. In the event, a new Bonn troupe was not recruited until 1789, when it featured the young singer Magdalena Willmann. Neefe and his musical colleagues were relieved finally to be able to resume their theatrical careers.

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The mid-Holocene decline of Tsuga canadensis (hereafter Tsuga) populations across eastern North America is widely perceived as a synchronous event, driven by pests/pathogens, rapid climate change, or both. Pattern identification and causal attribution are hampered by low stratigraphic density of pollen-sampling and radiometric dates at most sites, and by absence of highly resolved, paired pollen and paleoclimate records from single sediment cores, where chronological order of climatic and vegetational changes can be assessed. We present an intensely sampled (contiguous 1-cm intervals) record of pollen and water table depth (inferred from testate amoebae) from a single core spanning the Tsuga decline at Irwin Smith Bog in Lower Michigan, with high-precision chronology. We also present an intensively sampled pollen record from Tower Lake in Upper Michigan. Both sites show high-magnitude fluctuations in Tsuga pollen percentages during the pre-decline maximum. The terminal decline is dated at both sites ca. 5000 cal yr BP, some 400 years later than estimates from other sites and data compilations. The terminal Tsuga decline was evidently heterochronous across its range. A transient decline ca. 5350 cal yr BP at both sites may correspond to the terminal decline at other sites in eastern North America. At Irwin Smith Bog, the terminal Tsuga decline preceded an abrupt and persistent decline in water table depths by;200 years, suggesting the decline was not directly driven by abrupt climate change. The Tsuga decline may best be viewed as comprising at least three phases: a long-duration predecline maximum with high-magnitude and high-frequency fluctuations, followed by a terminal decline at individual sites, followed in turn by two millennia of persistently low Tsuga populations. These phases may not be causally linked, and may represent dynamics taking place at multiple temporal and spatial scales. Further progress toward understanding the phenomenon requires an expanded network of high-resolution pollen and paleoclimate chronologies.

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Vitamin A plays a central role in epithelial integrity and immune function. Given the risk of infection after transplantation, adequate vitamin A concentrations may be important in patients with a transplant. We assessed whether there was an association between retinol concentration and all-cause mortality in renal transplant recipients.

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Romanticism and Blackwood's Magazine is inspired by the ongoing critical fascination with Blackwood's Edinburgh Magazine, and the burgeoning recognition of its centrality to the Romantic age. Though the magazine itself was published continuously for well over a century and a half, this volume concentrates specifically on those years when William Blackwood was at the helm, beginning with his founding of the magazine in 1817 and closing with his death in 1834. These were the years when, as Samuel Taylor Coleridge put it in 1832, Blackwood's reigned as 'an unprecedented Phenomenon in the world of letters.' The magazine placed itself at the centre of the emerging mass media, commented decisively on all the major political and cultural issues that shaped the Romantic movement, and published some of the leading writers of the day, including Coleridge, Thomas De Quincey, John Galt, Felicia Hemans, James Hogg, Walter Scott, and Mary Shelley.

'This much-needed volume reminds us not only why Blackwood's was the most influential periodical publication of the time, but also how its writers, writings, and critical agendas continue to shape so many of the scholarly concerns of Romantic studies in the twenty-first century.' - Charles Mahoney, Associate Professor, University of Connecticut, USA

List of Illustrations
Acknowledgements
Abbreviations
Notes on Contributors
'A character so various, and yet so indisputably its own': A Passage to Blackwood's Edinburgh Magazine; R.Morrison & D.S.Roberts
PART I: BLACKWOOD'S AND THE PERIODICAL PRESS
Beginning Blackwood's: The Right Mix of Dulce and Ùtile; P.Flynn
John Gibson Lockhart and Blackwood's: Shaping the Romantic Periodical Press; T.Richardson
From Gluttony to Justified Sinning: Confessional Writing in Blackwood's and the London Magazine; D.Higgins
Camaraderie and Conflict: De Quincey and Wilson on Enemy Lines; R.Morrison
Selling Blackwood's Magazine, 1817-1834; D.Finkelstein
PART II: BLACKWOOD'S CULTURE AND CRITICISM
Blackwood's 'Personalities'; T.Mole
Communal Reception, Mary Shelley, and the 'Blackwood's School' of Criticism; N.Mason
Blackwoodian Allusion and the Culture of Miscellaneity; D.Stewart
Blackwood's Edinburgh Magazine in the Scientific Culture of Early Nineteenth-Century Edinburgh; W.Christie
The Art and Science of Politics in Blackwood's Edinburgh Magazine, c. 1817-1841; D.Kelly
Prosing Poetry: Blackwood's and Generic Transposition, 1820-1840; J.Camlot
PART III: BLACKWOOD'S FICTIONS
Blackwood's and the Boundaries of the Short Story; T.Killick
The Edinburgh of Blackwood's Edinburgh Magazine and James Hogg's Fiction; G.Hughes
'The Taste for Violence in Blackwood's Magazine'; M.Schoenfield
PART IV: BLACKWOOD'S AT HOME
John Wilson and Regency Authorship; R.Cronin
John Wilson and Sport; J.Strachan
William Maginn and the Blackwood's 'Preface' of 1826; D.E.Latané, Jr.
All Work and All Play: Felicia Hemans's Edinburgh Noctes; N.Sweet
PART V: BLACKWOOD'S ABROAD
Imagining India in Early Blackwood's; D.S.Roberts
Tales of the Colonies: Blackwood's, Provincialism, and British Interests Abroad; A.Jarrells
Selected Bibliography
Index

ROBERT MORRISON is Queen's National Scholar at Queen's University, Kingston, Ontario, Canada. His book, The English Opium-Eater: A Biography of Thomas De Quincey was a finalist for the James Tait Black Prize. He has edited writings by Jane Austen, Leigh Hunt, Thomas De Quincey, and John Polidori.
DANIEL SANJIV ROBERTS is Reader in English at Queen's University Belfast, UK. His publications include a monograph, Revisionary Gleam: De Quincey, Coleridge, and the High Romantic Argument (2000), and major critical editions of Thomas De Quincey's Autobiographic Sketches and Robert Southey's The Curse of Kehama; the latter was cited as a Distinguished Scholarly Edition by the MLA. He is currently working on an edition of Charles Johnstone's novel The History of Arsaces, Prince of Betlis for the Early Irish Fiction series.

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Here we report two novel 17-mer amidated linear peptides (TsAP-1 and TsAP-2) whose structures were deduced from cDNAs cloned from a venom-derived cDNA library of the Brazilian yellow scorpion, Tityus serrulatus. Both mature peptides were structurally-characterised following their location in chromatographic fractions of venom and synthetic replicates of each were subjected to a range of biological assays. The peptides were each active against model test micro-organisms but with different potencies. TsAP-1 was of low potency against all three test organisms (MICs 120-160µM), whereas TsAP-2 was of high potency against the Gram-positive bacterium, Staphylococcus aureus (MIC 5µM) and the yeast, Candida albicans (10µM). Haemolytic activity of TsAP-1 was low (4% at 160µM) and in contrast, that of TsAP-2 was considerably higher (18% at 20µM). Substitution of four neutral amino acid residues with Lys residues in each peptide had dramatic effects on their antimicrobial potencies and haemolytic activities, particularly those of TsAP-1. The MICs of the enhanced cationic analogue (TsAP-S1) were 2.5µM for S.aureus/C.albicans and 5µM for E.coli but with an associated large increase in haemolytic activity (30% at 5µM). The same Lys residue substitutions in TsAP-2 produced a dramatic effect on its MIC for E.coli lowering this from >320µM to 5µM. TsAP-1 was ineffective against three of the five human cancer cell lines tested while TsAP-2 inhibited the growth of all five. Lys residue substitution of both peptides enhanced their potency against all five cell lines with TsAp-S2 being the most potent with IC50 values ranging between 0.83 and 2.0 µM. TsAP-1 and TsAP-2 are novel scorpion venom peptides with broad spectrum antimicrobial and anticancer cell activities the potencies of which can be significantly enhanced by increasing their cationicity.

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Pavements and bridges are subject to a continuous degradation due to traffic aggressiveness, ageing and environmental factors. A rational transport policy requires the monitoring of this transport infrastructure in order to provide adequate maintenance and guarantee the required levels of transport service and safety. This paper investigates the use of an instrumented vehicle fitted with accelerometers on its axles to monitor the dynamics of bridges. A simplified quarter carbridge interaction model is used in theoretical simulations and the natural frequency of the bridge is extracted from the spectra of the vehicle accelerations. The accuracy is better at lower speeds and for smooth road profiles. The structural damping of the bridge was also monitored for smooth and rough road profiles. The magnitude of peaks in the power spectral density of the vehicle accelerations decreased with increasing bridge damping and this decrease was easier to detect the smoother the road profile.