917 resultados para Perkins, Revere: The evolution of grammar


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Chimpanzees are native only to the jungles of equatorial Africa, but for the last hundred years, they have also lived in captivity in the United States, most commonly in biomedical research laboratories, but also at Air Force bases for experiments for the space program, at accredited and unaccredited zoos, at circuses, as performers in Hollywood and even in private homes and backyards as pets. But that has been gradually evolving over the last few decades, as more and more chimpanzees move to newly-established chimpanzee sanctuaries. That transition was already underway even before the announcement by the National Institutes of Health (NIH) last year that it will retire all of its remaining chimpanzees from labs to sanctuaries. By thoroughly examining the evolution of these sanctuaries leading up to that seminal decision, along with the many challenges they face, including money, medical care, conflicting philosophies on the treatment of animals and the pitfalls that have led other sanctuaries to the brink of ruin, we can take away a better understanding of why chimpanzee sanctuaries are needed and why caretakers of other animal species are now looking to the chimpanzee sanctuary movement as a model to show how animals can be cared for in retirement.

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The use of whole-genome phylogenetic analysis has revolutionized our understanding of the evolution and spread of many important bacterial pathogens due to the high resolution view it provides. However, the majority of such analyses do not consider the potential role of accessory genes when inferring evolutionary trajectories. Moreover, the recently discovered importance of the switching of gene regulatory elements suggests that an exhaustive analysis, combining information from core and accessory genes with regulatory elements could provide unparalleled detail of the evolution of a bacterial population. Here we demonstrate this principle by applying it to a worldwide multi-host sample of the important pathogenic E. coli lineage ST131. Our approach reveals the existence of multiple circulating subtypes of the major drug–resistant clade of ST131 and provides the first ever population level evidence of core genome substitutions in gene regulatory regions associated with the acquisition and maintenance of different accessory genome elements.

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The Los Negritos porphyry copper deposit is located ~ 4 km to the northeast of Carmen de Andacollo Mine in the Chilean Cretaceous metallogenic belt. The mineralization is hosted in andesite of the Quebrada Marquesa Formation and a series of at least four early to intramineral porphyry intrusive rock types: plagioclase quartz biotite porphyry (P1b and P1a dated at 109.60± 0.75 Ma and 107.22± 0.40 Ma); plagioclase biotite porphyry (P2: 106.30 ± 0.47 Ma); and quartz plagioclase biotite porphyry (P3: 106.19 ± 0.42 Ma). These units are cut by late‐ to post‐mineral plagioclase‐hornblende porphyritic rocks (P4b: 106.20 ± 0.69 Ma and P4a: 106.50 ± 0.68 Ma). The earliest intrusive units (P1) were affected by an initial stage of K‐feldspar‐biotite alteration, with chalcopyrite, molybdenite (date at 108.5 ± 0.5 Ma) and gold (up to 0.11 ppm), and the surrounding volcanic host rock was overprinted by chlorite‐epidote dominated (propylitic) alteration. Subsequent to the P2 and P3 intrusion, these rocks were affected by albite and then a second stage of potassic alteration. The Ti and Ba contents in hydrothermal biotite are notably lower (typically Ti = 0.100‐0.144 a.p.f.u. and Ba = 0.001‐0.005 a.p.f.u) than in magmatic ones (generally Ti = 0.186‐0.222 a.p.f.u. and Ba = 0.014‐0.023 a.p.f.u.), and constitute an excellent discriminant of the nature of biotite. These early stages of alteration were overprinted by copper‐molybdenum bearing chlorite‐sericite alteration at 106.60 ± 0.5 Ma (Re‐Os age in molybdenite) and by quartz‐sericite‐pyrite veins (phyllic), respectively in the southwest and northeast areas. The average temperature associated with these two alteration facies is estimated around 305 °C. Weak albite‐calcite alteration, spatially associated with sulfosalts and distributed along the margins of P3, overprinted the phyllic facies. The intrusive rock units at the Los Negritos and Carmen de Andacollo deposits are geochemically classified as diorite to granodiorite with a calc‐alkaline magmatic affinity, and formed in a volcanic arc setting from partial melting of a metasomatized mantle wedge. They are interpreted to be cogenetic, and related to a common long‐lived magma chamber that emplaced during a period of tectonic inversion known as the Subhercynian, Peruvian or Pacific event.

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Lactase persistence, the ability to digest the milk sugar lactose in adulthood, is highly associated with a T allele situated 13,910 bp upstream from the actual lactase gene in Europeans. The frequency of this allele rose rapidly in Europe after transition from hunter–gatherer to agriculturalist lifestyles and the introduction of milkable domestic species from Anatolia some 8000 years ago. Here we first introduce the archaeological and historic background of early farming life in Europe, then summarize what is known of the physiological and genetic mechanisms of lactase persistence. Finally, we compile the evidence for a co-evolutionary process between dairying culture and lactase persistence. We describe the different hypotheses on how this allele spread over Europe and the main evolutionary forces shaping this process. We also summarize three different computer simulation approaches, which offer a means of developing a coherent and integrated understanding of the process of spread of lactase persistence and dairying.

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The Spanish transition, the political process through which Spain ceased to be a dictatorship to become a democracy, was accompanied by the dissolution of the National Movement, the institutional support for the chain of the Movement Press from its beginnings, in April 1977. This fact, among others, contributed to the /Sur/, the regional reference newspaper for the chain in Andalusia, evolving both structurally and ideologically to adapt itself to the new political regime. This study applies content analysis to editorials, articles and columns published by the newspaper between 1975 and 1978, exploring the process through which the regional newspaper edited in Málaga abandoned its propaganda function with regard to the Government, considering it undemocratic, and supported the PSOE, presenting it as the best alternative to the UCD in the Spanish Executive, thus taking on its role as a political agent.

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The Belgian coastal plain occupies a key position as it is located at the transition between the Southern North Sea Basin and the Strait of Dover. It is characterized by thick sequences (> 20 m) of Pleistocene terrestrial and littoral sediments. Yet the wider stratigraphical and palaeo-environmental significance of these sediments received little attention. In this paper we draw on the results of a recent sedimentological study based on > 100 drillings that spans the Pleistocene sequence, and present new biostratigraphical (pollen, foraminifera, ostracods) data, all revealing a complex history of deposition. The record includes evidence of the development of incised-valley systems that were initiated in the late Middle and Late Pleistocene. Five phases of fluvial incision can be identified. The majority of the infills are deposited in an estuarine environment that passes into a fluvial environment land inward, except the Weichselian infill which has a predominant fluvial origin. The greatest part of the most seaward located zone of the western coastal plain was free of valley incisions, there, shallow marine sediments built up the record. Local biostratigraphical investigations provide a timeframe. The result is placed in a regional context.

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Ireland is a latecomer to Public Private Partnership (PPP) having only adopted it in 1998. Prior to the credit crisis, Ireland followed the UK model with PPPs being implemented in transport, education, housing/urban regeneration and water/wastewater. Having stalled during the credit crisis, PPP has been reactivated recently with the domestic infrastructure stimulus programme . The focus of this paper is on Ireland as a younger participant in PPP and the nexus between adoption patterns and sustainability characteristics of Irish PPP. Using document analysis and exploratory interviews, the paper examines the reasons for Ireland’s interest in PPP which cannot be attributed to economic rationales alone. We consider three explanations: voluntary adoption – where the UK model was closely followed as part of a domestic modernisation agenda; coercive adoption – where PPP policy was forced upon public sector organisations; and institutional isomorphism – where institutional creation and change around PPP was promoted to help public sector organisations gain institutional legitimacy. We find evidence of all three patterns with coercive adoption becoming more relevant in recent years, which is likely to affect sustainability adversely unless incentives for voluntary adoption are strengthened and institutional capacity building is boosted.

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This paper describes the evolution of a ‘Design - Build-Fly’ (DBF) approach to the delivery and assessment of a Stage Three Aircraft Design module. It focuses on the primary learning outcomes around the design and manufacturing functions associated with the development of a remotely controlled aircraft. The work covers a six year period from 2011 to present mapping the transformation of the module from report based assessment to a more hands on approach resulting in a fully functioning remotely controlled aircraft. Results show that both the staff and student experience improved across key performance metrics including student feedback, learning and competency development. Challenges still remain in methods of placing students within teams and maintaining technical rigour in reporting as students develop vocational skills and more reflective writing styles.

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[EN] Global warming can affect nesting success of sea turtles due to the rise of the sea level and the subsequent increased inundation or erosion of nesting beaches. Moreover, it can reduce male production to levels that can alter reproduction due to their temperature dependant sex determination (TSD). Now, mean nest temperatures all around the world predict a predominance of female hatchlings, and this trend may increase with global warming in the next decades.

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[EN] Two new 40Ar/39Ar ages (*) and previously published K/Ar ages of basaltic pillow lava flows are coeval with closely-related fossiliferous marine layers, allowing us to establish the beginning (5.8; 5.0; 4.8Ma at Ajuí, Fuerteventura Island and 4.8±0.03Ma (2?)* at Tamaraceite) and a middle stage (4.20±0.18Ma (2?)* at La Esfinge in Gran Canaria Island) of Early Pliocene marine deposits in the Canary Islands. Here the presence of tropicopolitan fossils (Megaselachus megalodon, Janthina typica) suggests the influence of a possible Central American Circumtropical Current during the Pliocene and in the North Atlantic basin.

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La Banque mondiale propose la bonne gouvernance comme la stratégie visant à corriger les maux de la mauvaise gouvernance et de faciliter le développement dans les pays en développement (Carayannis, Pirzadeh, Popescu & 2012; & Hilyard Wilks 1998; Leftwich 1993; Banque mondiale, 1989). Dans cette perspective, la réforme institutionnelle et une arène de la politique publique plus inclusive sont deux stratégies critiques qui visent à établir la bonne gouvernance, selon la Banque et d’autres institutions de Bretton Woods. Le problème, c’est que beaucoup de ces pays en voie de développement ne possèdent pas l’architecture institutionnelle préalable à ces nouvelles mesures. Cette thèse étudie et explique comment un état en voie de développement, le Commonwealth de la Dominique, s’est lancé dans un projet de loi visant l’intégrité dans la fonction publique. Cette loi, la Loi sur l’intégrité dans la fonction publique (IPO) a été adoptée en 2003 et mis en œuvre en 2008. Cette thèse analyse les relations de pouvoir entre les acteurs dominants autour de évolution de la loi et donc, elle emploie une combinaison de technique de l’analyse des réseaux sociaux et de la recherche qualitative pour répondre à la question principale: Pourquoi l’État a-t-il développé et mis en œuvre la conception actuelle de la IPO (2003)? Cette question est d’autant plus significative quand nous considérons que contrairement à la recherche existante sur le sujet, l’IPO dominiquaise diverge considérablement dans la structure du l’IPO type idéal. Nous affirmons que les acteurs "rationnels," conscients de leur position structurelle dans un réseau d’acteurs, ont utilisé leurs ressources de pouvoir pour façonner l’institution afin qu’elle serve leurs intérêts et ceux et leurs alliés. De plus, nous émettons l’hypothèse que: d’abord, le choix d’une agence spécialisée contre la corruption et la conception ultérieure de cette institution reflètent les préférences des acteurs dominants qui ont participé à la création de ladite institution et la seconde, notre hypothèse rivale, les caractéristiques des modèles alternatifs d’institutions de l’intégrité publique sont celles des acteurs non dominants. Nos résultats sont mitigés. Le jeu de pouvoir a été limité à un petit groupe d’acteurs dominants qui ont cherché à utiliser la création de la loi pour assurer leur légitimité et la survie politique. Sans surprise, aucun acteur n’a avancé un modèle alternatif. Nous avons conclu donc que la loi est la conséquence d’un jeu de pouvoir partisan. Cette recherche répond à la pénurie de recherche sur la conception des institutions de l’intégrité publique, qui semblent privilégier en grande partie un biais organisationnel et structurel. De plus, en étudiant le sujet du point de vue des relations de pouvoir (le pouvoir, lui-même, vu sous l’angle actanciel et structurel), la thèse apporte de la rigueur conceptuelle, méthodologique, et analytique au discours sur la création de ces institutions par l’étude de leur genèse des perspectives tant actancielles que structurelles. En outre, les résultats renforcent notre capacité de prédire quand et avec quelle intensité un acteur déploierait ses ressources de pouvoir.

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The role of the director as the individual who harnesses and controls resources to shape the theatrical product to a personal artistic vision, begins to emerge in British theatre in the early years of the twentieth century. What distinguishes the role from that of the actor-manager who had led the profession since the seventeenth century, is that it separates off from the leading actor in performance. The power and authority of the director (or producer as he or she tended to be known initially) is exercised in the pre-performance stage. In the first half of the century there were still old-style actor-managers—Donald Wolfit is a prime example—and many of the new directors had begun their careers as actors and some continued to act their in their own productions. But the perception of the function of the director began to change radically. In part this was linked to the early attempts to create a new model of producing company or ‘repertory’ theatre which required a different set of administrative as well as artistic skills to tackle the challenge of a short-run system of multiple play production. This became especially important in the developing network of regional repertory theatres which were established as autonomous, locally-specific institutions predicated on policies opposed to the dominant commercial ethos. The best-known of the early directors, most notably H.Granville Barker, confined their radical experiments to short-lived metropolitan experiments, or, as in the case of Terence Gray and J.B.Fagan, operated within the influential Oxbridge nexus. Others such as H.K.Ayliff, Herbert Prentice, William Armstrong and William Bridges-Adams remain comparatively obscure because of their long-term ‘provincial’ connections or, as in the case of Nugent Monck and Edy Craig because their creativity was largely channelled through amateur actors. This chapter will explore the evolving role of the director as both a necessary functionary and an artistic innovator within the changing structures of British theatre.

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"A lecture delivered to the ECLAC/CDCC Training Workshop in Evidence-based Social Policy Formulation for the Caribbean, Port of Spain, Trinidad and Tobago 28-31 October 2002 and Kingston, Jamaica, 26-28 November 2002"

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Ideas about the evolution of imperfect mimicry are reviewed. Their relevance to the colours patterns of hoverflies (Diptera, Syrphidae) are discussed in detail. Most if not all of the hoverflies labelled as mimetic actually are mimics. The apparently poor nature of their resemblance does not prevent them from obtaining at least some protection from suitably experienced birds. Mimicry is a dominant theme of this very large family of Diptera, with at least a quarter of all species in Europe being mimetic. Hoverfly mimics fall into three major groups according to their models, involving bumblebees, honeybees and social wasps. There are striking differences in the general levels of mimetic fidelity and relative abundances of the three groups, with accurate mimicry, low abundance and polymorphism characterizing the bumblebee mimics: more than half of all the species of bumblebee mimics are polymorphic. Mimics of social wasps tend to be poor mimics, have high relative abundance, and polymorphism is completely absent. Bumblebee models fall into a small number of Muellerian mimicry rings which are very different between the Palaearctic and Nearctic regions. Social wasps and associated models form one large Muellerian complex. Together with honeybees, these complexes probably form real clusters of forms as perceived by many birds. All three groups of syrphid mimics contain both good and poor mimics; some mimics are remarkably accurate, and have close morphological and behavioural resemblance. At least some apparently 'poor' mimetic resemblances may be much closer in birds' perception than we imagine, and more work needs to be done on this. Bumblebees are the least noxious and wasps the most noxious of the three main model groups. The basis of noxiousness is different, with bumblebees being classified as non-food, whereas honeybees and wasps are nasty-tasting and (rarely) stinging. The distribution of mimicry is exactly what would be expected from this ordering, with polymorphic and accurate forms being a key feature of mimics of the least noxious models, while highly noxious models have poor-quality mimicry. Even if the high abundance of many syrphid mimics relative to their models is a recent artefact of man-made environmental change, this does not preclude these species from being mimics. It seems unlikely that bird predation actually controls the populations of adult syrphids. Being rare relative to a model may have promoted or accelerated the evolution of perfect mimicry: theoretically this might account for the pattern of rare good mimics and abundant poor ones, but the idea is intrinsically unlikely. Many mimics seem to have hour-to-hour abundances related to those of their models, presumably as a result of behavioural convergence. We need to know much more about the psychology of birds as predators. There are at least four processes that need elucidating: (a) learning about the noxiousness of models; (b) the erasing of that learning through contact with mimics (extinction, or learned forgetting); (c) forgetting; (d) deliberate risk-taking and the physiological states that promote it. Johnston's (2002) model of the stabilization of imperfect mimicry by kin selection is unlikely to account for the colour patterns of hoverflies. Sherratt's (2002) model of the influence of multiple models potentially accounts for all the patterns of hoverfly mimicry, and is the most promising avenue for testing.