15 resultados para Churubusco, batalla de-1847

em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast


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Over the last decade, much new research has appeared on the subject of the Great Irish Famine but, remarkably, a major political event during the famine - the 1847 general election - has received virtually no mention. Recent work on politics in this period has tended to concentrate on political reaction in Britain rather than Ireland. The aim of this article is to examine the response of Irish politicians to the famine during the general election of 1847. The main source has been the political addresses and nomination speeches of most of the 140 candidates. The evidence from this material shows that, although the famine was an important matter in many constituencies, it was not the dominant issue countrywide. Various proposals to deal with the famine emerged, but there was an absence of agreed, practical measures to deal with immediate problems. The parties in Ireland failed to create a common platform to challenge the government over its efforts. Ideological constraints played an important part in these failures. The general election of 1847 represents a lost opportunity to tackle some of the effects of the famine.

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This paper investigates the way in which the ‘problem of poverty’ in Ireland was encountered, constructed and debated by members of the Irish intellectual and political elite in the decades between the Great Famine and the outbreak of the land war in the late 1870s. This period witnessed acute social upheavals in Ireland, from the catastrophic nadir of the Famine, through the much-vaunted economic recovery of the 1850s–1860s, to the near-famine panic of the late 1870s (itself prefigured by a lesser agricultural crisis in 1859–63). The paper focuses on how a particular elite group – the ‘Dublin School’ of political economists and their circle, and most prominently William Neilson Hancock and John Kells Ingram – sought to define and investigate the changing ‘problem’, shape public attitudes towards the legitimacy of welfare interventions and lobby state officials in the making of poor law policy in this period. It suggests that the crisis of 1859–63 played a disproportionate role in the reevaluation of Irish poor relief and in promoting a campaign for an ‘anglicisation’ of poor law measures and practice in Ireland.

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Legislation enabling colonial territories to import unauthorised foreign reprints subject to the payment of an import duty, to be collected for the benefit of British publishers.
The commentary explores the background to the Foreign Reprints Act 1847, and in particular, the differences between the British and colonial markets for literary works, and the introduction of 'responsible government' in the colonies. It also considers the movement in the late 1860s and early 1870s, on the part of the British book trade, to have the legislation repealed, as well as the efforts of the Canadian legislature to replace the import scheme with a system of compulsory licensing, set against the backdrop of increasingly fractious Anglo-Canadian copyright relations. The Canadian demands for compulsory licensing scheme were by and large abandoned, and the 1847 Act remained on the statute books until the passing of the Copyright Act 1911.

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Direction repulsion describes the phenomenon in which observers typically overestimate the direction difference between two superimposed motions moving in different directions (Marshak & Sekuler, Science 205(1979) 1399). Previous research has found that, when a relatively narrow range of distractor speeds is considered, direction repulsion of a target motion increases monotonically with increasing speed of the distractor motion. We sought to obtain a more complete measurement of this speed-tuning function by considering a wider range of distractor speeds than has previously been used. Our results show that, contrary to previous reports, direction repulsion as a function of distractor speed describes an inverted U-function. For a target of 2.5deg/s, we demonstrate that the attenuation of repulsion magnitude with high-speed disractors can be largely explained in terms of the reduced apparent contrast of the distractor. However, when we reduce target motion speed, this no longer holds. When considered from the perspective of Edwards et al.s (Edwards, Badcock, & Smith, Vision Research 38 (1998) 1573) two global-motion channels, our results suggest that direction repulsion is speed dependent when the distractor and target motions are processed by different globalmotion channels, but is not speed dependent when both motions are processed by the same, high-speed channel. The implications of these results for models of direction repulsion are discussed.

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Mural cells (smooth muscle cells and pericytes) regulate blood flow and contribute to vessel stability. We examined whether mural cell changes accompany age-related alterations in the microvasculature of the central nervous system. The retinas of young adult and aged Wistar rats were subjected to immunohistofluorescence analysis of a-smooth muscle actin (SMA), caldesmon, calponin, desmin, and NG2 to identify mural cells. The vasculature was visualized by lectin histochemistry or perfusion of horse-radish peroxidase, and vessel walls were examined by electron microscopy. The early stage of aging was characterized by changes in peripheral retinal capillaries, including vessel broadening, thickening of the basement membrane, an altered length and orientation of desmin filaments in pericytes, a more widespread SMA distribution and changes in a subset of pre-arteriolar sphincters. In the later stages of aging, loss of capillary patency, aneurysms, distorted vessels, and foci of angiogenesis were apparent, especially in the peripheral deep vascular plexus. The capillary changes are consistent with impaired vascular autoregulation and may result in reduced pericyte-endothelial cell contact, destabilizing the capillaries and rendering them susceptible to angiogenic stimuli and endothelial cell loss as well as impairing the exchange of metabolites required for optimal neuronal function. This metabolic uncoupling leads to reactivation of

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An array-based approach is put forward to obtain insight into reactivity under mechanochemical solvent-free conditions. We describe a survey of sixty potential reactions between twelve metal salts MX2 {(M = Cu, X-2 = (OAc)(2), (HCO2)(2), (F3CCO2)(2), (acac)(2), (F(6)acac)(2), (NO3)(2), SO4; M = Ni, X-2 = (OAc)(2), (NO3)(2), SO4; M = Zn, X-2 (OAc)(2), (NO3)(2)} and five bridging organic ligands {isonicotinic acid (HINA), 1,4-benzenedicarboxylic acid (H2BDC), acetylenedicarboxylic acid (H(2)ADC), 1,3,5-benzenetricarboxylic acid (H3BTC), 4,4'-bipyridyl (BIPY). Reaction conditions involved a ball mill, applied for 15 min at 30 Hz, without external heating. When examined by XRPD, forty of the combinations gave detectable reactions, thirty-eight with crystalline products. Of these, twenty-nine reactions were quantitative (consuming all of at least one reactant). Comparison of XRPD patterns with patterns simulated from single crystal X-ray diffraction data in the Cambridge Structural Database allowed structural identification of six products. Of particular interest are the microporous framework materials [Cu(INA)(2)] and [Cu-3(BTC)(2)] (HKUST-1) obtained by reaction of the corresponding carboxylic acids with copper acetate. Other non-porous polymers with 3-dimensional connectivity, [Ni(ADC)(H2O)(4)], or 1-dimensional connectivity, [Cu(acac)(2)(BIPY)] and [Cu(F6acac)(BIPY)] were also obtained. Reaction between zinc acetate and H2ADC gave a new product which had not previously been characterised by single-crystal X-ray crystallography, but whose XRPD pattern suggests that it is isostructural with the known nickel polymer [Ni(ADC)(H2O)(4)]. Two further isostructural nickel and zinc products were obtained in reactions between HINA and nickel nitrate and zinc nitrate. Trends observed within the array are discussed. Copper acetate and copper formate were the most effective starting materials for reaction with carboxylic acids, potentially related to the basicity of their anions and the solvating effects of the formic and acetic acid byproducts. Amongst the ligands there was a general negative corelation between melting point and reactivity. The issue of pore templating in microporous phases and the generation of new structures is also discussed in relation to the Cu(INA)(2), Cu-3(BTC)(2) and nickel nitrate-BIPY systems. Overall, the study suggests that mechanochemical reactivity between metal salts and organic ligands under solvent free conditions is remarkably general. Use of array-based approaches as demonstrated here is advocated a useful way to reveal underlying trends in reactivity under solvent free mechanochemical conditions and to highlight particular cases for more detailed study.

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Chitons are often referred to as “living fossils” in part because they are proposed as one of the earliest-diverging groups of living molluscs, but also because the gross morphology of the polyplacophoran shell has been conserved for hundreds of millions of years. As such, the analysis of evolution and radiation within polyplacophorans is of considerable interest not only for resolving the shape of pan-molluscan phylogeny but also as model organisms for the study of character evolution. This study presents a new, rigorous cladistic analysis of the morphological characters used in taxonomic descriptions for chitons in the living suborder Lepidopleurina Thiele, 1910 (the earliest-derived living group of chitons). Shell-based characters alone entirely fail to recover any recognized subdivisions within the group, which may raise serious questions about the application of fossil data (from isolated shell valves). New analysis including characters from girdle armature and gill arrangements recovers some genera within the group but also points to the lack of monophyly within the main genus Leptochiton Gray, 1847. Additional characters from molecular data and soft anatomy, used in combination, are clearly needed to resolve questions of chiton relationships. However, the data sets currently available already provide interesting insights into the analytical power of traditional morphology as well as some knowledge about the early evolution and radiation of this group.

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We discuss the properties of the lifetime or the time-delay matrix Q(E) for multichannel scattering, which is related to the scattering matrix S(E) by Q = i?S(dS†/dE). For two overlapping resonances occurring at energies E with widths G(? = 1, 2), with an energy-independent background, only two eigenvalues of Q(E) are proved to be different from zero and to show typical avoided-crossing behaviour. These eigenvalues are expressible in terms of the four resonance parameters (E , G) and a parameter representing the strength of the interaction of the resonances. An example of the strong and weak interaction in an overlapping double resonance is presented for the positronium negative ion. When more than two resonances overlap (? = 1, ..., N), no simple representation of each eigenvalue has been found. However, the formula for the trace of the Q-matrix leads to the expression d(E) = -?arctan[(G/2)/(E - E)] + d(E) for the eigenphase sum d(E) and the background eigenphase sum d(E), in agreement with the known form of the state density. The formulae presented in this paper are useful in a parameter fitting of overlapping resonances. © 2006 IOP Publishing Ltd.

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Lepidopleurida is the earliest diverged group of living polyplacophoran molluscs. They are found predominantly in the deep sea, including sunken wood, cold seeps, other abyssal habitats, and a few species are found in shallow water. The group is morphologically identified by anatomical features of their gills, sensory aesthetes, and gametes. Their shell features closely resemble the oldest fossils that can be identified as modern polyplacophorans. We present the first molecular phylogenetic study of this group, and also the first combined phylogenetic analysis for any chiton, including three gene regions and 69 morphological characters. The results show that Lepidopleurida is unambiguously monophyletic, and the nine genera fall into five distinct clades, which partly support the current view of polyplacophoran taxonomy. The genus Hanleyella Sirenko, 1973 is included in the family Protochitonidae, and Ferreiraellidae constitutes another distinct clade. The large cosmopolitan genus Leptochiton Gray, 1847 is not monophyletic; Leptochiton and Leptochitonidae sensu stricto are restricted to North Atlantic and Mediterranean taxa. Leptochitonidae s. str. is sister to Protochitonidae. The results also suggest two separate clades independently inhabiting sunken wood substrates in the south-west Pacific. Antarctic and other chemosynthetic-dwelling species may be derived from wood-living species. Substantial taxonomic revision remains to be done to resolve lepidopleuran classification, but the phylogeny presented here is a dramatic step forward in clarifying the relationships within this interesting group.

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Chitons are often referred to as "living fossils" in part because they are proposed as one of the earliest-diverging groups of living molluscs, but also because the gross morphology of the polyplacophoran shell has been conserved for hundreds of millions of years. As such, the analysis of evolution and radiation within polyplacophorans is of considerable interest not only for resolving the shape of pan-molluscan phylogeny but also as model organisms for the study of character evolution. This study presents a new, rigorous cladistic analysis of the morphological characters used in taxonomic descriptions for chitons in the living suborder Lepidopleurina Thiele, 1910 (the earliest-derived living group of chitons). Shell-based characters alone entirely fail to recover any recognized subdivisions within the group, which may raise serious questions about the application of fossil data (from isolated shell valves). New analysis including characters from girdle armature and gill arrangements recovers some genera within the group but also points to the lack of monophyly within the main genus Leptochiton Gray, 1847. Additional characters from molecular data and soft anatomy, used in combination, are clearly needed to resolve questions of chiton relationships. However, the data sets currently available already provide interesting insights into the analytical power of traditional morphology as well as some knowledge about the early evolution and radiation of this group.

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BACKGROUND:
It is compulsory that domestic football/soccer teams in UEFA competitions organise players' pre-participation medicals. Although screening guidelines have been established, these remain controversial. The findings of medical examinations can have lasting consequences for athletes and doctors. No previous studies have reported UEFA pre-participation screening results in semi-professional footballers. This study aims to further knowledge regarding 'normal' data in this population.

METHOD:
Retrospective audit and analysis of records of pre-season medicals for all male first-team players at one semi-professional Northern Ireland Premiership team between 2009-2012. Medicals were conducted by the club doctor following the UEFA proforma. Height, weight, blood pressure (BP), full blood count (FBC), dipstick urinalysis and resting electrocardiogram (ECG) were conducted by an independent nurse. Only one ECG must be documented during a player's career; other tests are repeated yearly.

RESULTS:
89 medicals from 47 players (6 goalkeepers, 11 defenders, 22 midfielders and 8 attackers; mean age 25.0 years (SD 4.86)) were reviewed. Mean height of the players was 179.3 cm (SD 5.90) with a mean weight of 77.6 kg (SD 10.5). Of 89 urine dipsticks, 7 were positive for protein; all 7 were normal on repeat testing following 48 hours of rest. Of 40 ECGs (mean ventricular rate 61.2 bpm (SD 11.6)), one was referred to cardiology (right bundle branch block; prolonged Q-T interval). No players were excluded from participation.

CONCLUSIONS:
This study provides important information about 'normal' values in a population of semi-professional footballers. Urinalysis showing protein is not uncommon but is likely to be normal on repeat testing.

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Mitochondrial complex I is a large, membrane-bound enzyme central to energy metabolism, and its dysfunction is implicated in cardiovascular and neurodegenerative diseases. An interesting feature of mammalian complex I is the so-called A/D transition, when the idle enzyme spontaneously converts from the active (A) to the de-active, dormant (D) form. The A/D transition plays an important role in tissue response to ischemia and rate of the conversion can be a crucial factor determining outcome of ischemia/reperfusion. Here, we describe the effects of alkali cations on the rate of the D-to-A transition to define whether A/D conversion may be regulated by sodium.At neutral pH (7–7.5) sodium resulted in a clear increase of rates of activation (D-to-A conversion) while other cations had minor effects. The stimulating effect of sodium in this pH range was not caused by an increase in ionic strength. EIPA, an inhibitor of Na+/H+antiporters, decreased the rate of D-to-A conversion and sodium partially eliminated this effect of EIPA. At higher pH (> 8.0), acceleration of the D-to-A conversion by sodium was abolished, and all tested cations decreased the rate of activation, probably due to the effect of ionic strength.The implications of this finding for the mechanism of complex I energy transduction and possible physiological importance of sodium stimulation of the D-to-A conversion at pathophysiological conditions in vivo are discussed.

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This article examines the problems and paradoxes in the representation of the future in three nineteenth-century Spanish works: El futuro Madrid (1868) by Fernández de los Ríos, ‘Madrid en el siglo xxi’ (1847) by Neira de Mosquera, and Ni en la vida ni en la muerte by Juan Bautista Amorós (Silverio Lanza). While these texts demonstrate Spain’s participation in the general movement towards using the future as a setting for literary works, they do not corroborate the theory that the nineteenth century was a time of optimism and belief in the doctrine of Progress. Concepts derived from discussions of the future in the history of ideas, such as historia magistra vitae, are shown to be relevant to discussion of these futuristic fictions, in sometimes unexpected ways.