886 resultados para Thought in a hostile world: the evolution of human cognition
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Phosphine is the only economically viable fumigant for routine control of insect pests of stored food products, but its continued use is now threatened by the world-wide emergence of high-level resistance in key pest species. Phosphine has a unique mode of action relative to well-characterised contact pesticides. Similarly, the selective pressures that lead to resistance against field sprays differ dramatically from those encountered during fumigation. The consequences of these differences have not been investigated adequately. We determine the genetic basis of phosphine resistance in Rhyzopertha dominica strains collected from New South Wales and South Australia and compare this with resistance in a previously characterised strain from Queensland. The resistance levels range from 225 and 100 times the baseline response of a sensitive reference strain. Moreover, molecular and phenotypic data indicate that high-level resistance was derived independently in each of the three widely separated geographical regions. Despite the independent origins, resistance was due to two interacting genes in each instance. Furthermore, complementation analysis reveals that all three strains contain an incompletely recessive resistance allele of the autosomal rph1 resistance gene. This is particularly noteworthy as a resistance allele at rph1 was previously proposed to be a necessary first step in the evolution of high-level resistance. Despite the capacity of phosphine to disrupt a wide range of enzymes and biological processes, it is remarkable that the initial step in the selection of resistance is so similar in isolated outbreaks.
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Evidence of incongruence between mitochondrial and nuclear gene trees is now becoming documented with increasing frequency. Among the Old World monkeys, this discordance has been well demonstrated in the Cercopithecinae, but has not yet been investigated
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Pheromones are chemical cues released and sensed by individuals of the same species, which are of major importance in regulating reproductive and social behaviors of mammals. Generally, they are detected by the vomeronasal system (VNS). Here, we first investigated and compared an essential genetic component of vomeronasal chemoreception, that is, TRPC2 gene, of four marine mammals varying the degree of aquatic specialization and related terrestrial species in order to provide insights into the evolution of pheromonal olfaction in the mammalian transition from land to water. Our results based on sequence characterizations and evolutionary analyses, for the first time, show the evidence for the ancestral impairment of vomeronasal pheromone signal transduction pathway in fully aquatic cetaceans, supporting a reduced or absent dependence on olfaction as a result of the complete adaptation to the marine habitat, whereas the amphibious California sea lion was found to have a putatively functional TRPC2 gene, which is still under strong selective pressures, reflecting the reliance of terrestrial environment on chemical recognition among the semiadapted marine mammals. Interestingly, our study found that, unlike that of the California sea lion, TRPC2 genes of the harbor seal and the river otter, both of which are also semiaquatic, are pseudogenes. Our data suggest that other unknown selective pressures or sensory modalities might have promoted the independent absence of a functional VNS in these two species. In this respect, the evolution of pheromonal olfaction in marine mammals appears to be more complex and confusing than has been previously thought. Our study makes a useful contribution to the current understanding of the evolution of pheromone perception of mammals in response to selective pressures from an aquatic environment.
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The important pelagic fishery resources of northern Lake Tanganyika were identified after a preliminary scientific evaluation, and in Burundi, with governmental assistance they were rapidly developed and exploited more intensively until overfishing was thought to have occurred. At this point, legal measures were introduced in order to protect the resource by restricting fishing effort and maintaining the total yield near the apparent maximum sustained limit. Complementary biological research on the fish stocks did not accompany the rapid fishery development and now an intensive stock assessment programme has been launched by the Government and UNDP in order to define more precisely the available fish stocks and to consider, with the co-operation of the neighbouring lacustrine states, suitable ways of ensuring optimum levels of fish harvest from year to year.
The evolution of the medical professions in eighteenth-century Ireland: An institutional perspective
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Ireland, in the eighteenth century, followed the classic tripartite division of regular medical practitioners into physicians, surgeons and apothecaries. At the beginning of the century surgeons and apothecaries were regarded as mere tradesmen, but by the end of the century both were regarded as professionals and had the right to regulate their respective professions. Practitioners in different regions of Europe developed in a different manner, and eighteenth-century practitioners in Ireland developed independently from their English counterparts. In common with Britain and Europe in the eighteenth century, the total number of practitioners increased in Ireland, and by the end of the century, apothecaries were the largest group in Dublin, closely followed by the surgeons. Surgeons and apothecaries at the start of the eighteenth century belonged to the same guild. However in mid-century, St Luke's guild of apothecaries was established and this provided the apothecaries with a new identity that allowed them to pursue auto regulation, rather than hitherto, when they had been regulated by the physicians. This was vital to the apothecaries as they were in direct commercial competition with both the physicians and the surgeons and faced increasing pressure from both druggists and the disparate group of practitioners known as the irregulars. The 1765 County Infirmaries Act established a hospital in virtually every county in Ireland, and cast the surgeon as the primary medical officer in the countrywide network of hospitals. This legislation, which was unique in Europe, had the unintended consequence of elevating the status of the surgeons, as prior to this physicians were always in the ascendancy in the voluntary hospitals in Ireland and Britain, in contrast to France. The status of the surgeons was further enhanced by the establishment of the College of Surgeons in Ireland in 1784, which provided them with a new corporate identity, the authority to regulate the profession countrywide, and, also, the ability to educate surgeons in Ireland. The establishment of the College of Surgeons placed further pressure on the apothecaries to demonstrate that they also had a recognisable identity, and the authority to regulate their own profession. This was achieved with the 1791 Apothecaries Act which established the Apothecaries Hall and give the apothecaries the right to regulate themselves. This innovative legislation deemed the apothecaries a profession, and was enacted twenty-four years prior to similar legislation in Britain. Commercial pressure from druggists and, probably, irregulars expedited the requirement of the apothecaries to establish a new corporate identity, in order to distance themselves from these groups. The changing status of both apothecaries and surgeons had little effect on the physicians as a group, and, despite being the beneficiaries of a generous bequest from Sir Patrick Dun in 1711 to provide medical chairs in Dublin, the physicians displayed an inertia during the eighteenth century that was not in keeping with the developments that occurred in the contemporary Dublin medical world. The fact that it took ninety-five years, and that five acts of parliament, two House of Commons enquiries and a House of Lords enquiry were required to ensure that Dun's wishes were brought to fruition demonstrates that the physicians did not develop at the same pace as the other medical groups in the city. Had Dun’s bequest been implemented as he desired, Dublin, with a number of voluntary hospitals, would have been well placed to provide comprehensive tuition for medical students in the eighteenth century. It was not until the nineteenth century that the city, and the populace, benefited from this legacy. This thesis will trace these developments in the context of changes that occurred in contemporary medical education and diagnosis in Ireland, Britain and France. It will demonstrate that Irish practitioners developed independently, influenced mainly by local issues, but also by those who had travelled abroad and returned to Ireland with new concepts and ideas, ensuring that Irish medical practitioners had the institutional structure that could encompass the diagnostic and regulatory changes that would become accepted in the nineteenth century.
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In the United Kingdom wind power is recognised as the main source of renewable energy to achieve the European Union 2020 renewable energy targets. Currently over 50% of renewable power is generated from onshore wind with a large number of offshore wind projects in development. Recently the government has re-iterated its commitment to offshore wind power and has announced that offshore wind subsidies are to increase from £135/MWh to £140/MWh until 2019. This paper provides a detailed overview of the offshore wind power industry in the United Kingdom in terms of market growth, policy development and offshore wind farm costs. The paper clearly shows that the United Kingdom is the world leader for installed offshore wind power capacity as pro-active policies and procedures have made it the most attractive location to develop offshore wind farm arrays. The key finding is that the United Kingdom has the potential to continue to lead the world in offshore wind power as it has over 48 GW of offshore wind power projects at different stages of operation and development. The growth of offshore wind power in the United Kingdom has seen offshore wind farm costs rise and level off at approximately £3 million/MW, which are higher than onshore wind costs at £1.5–2 million/MW. Considering the recent increase in offshore wind power subsidies and plans for 48 GW of offshore wind power could see more offshore wind power becoming increasingly financially competitive with onshore wind power. Therefore offshore wind power is likely to become a significant source of electricity in the United Kingdom beyond 2020.
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The evolution of the drug trafficking network –so-called– ‘Cartel del Norte del Valle’, is studied using network analysis methods. We found that the average length between any pair of its members was bounded by 4 –an attribute of smallworld networks. In this tightly connected network, informational shocks induce fear and the unleashing of searches of threatening nodes, using available paths. Lethal violence ensues in clusters of increasing sizes that fragment the network, without compromising, however, the survival of the largest component, which proved to be resilient to massive violence. In spite of a success from the point of view of head counting, the US’ socialization program for drug traffickers did not effectively change the cyclical dynamics of the drug dealing business: war survivors took over what was left from the old network initiating a new cycle of business and violence.
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An evolutionary perspective on human thought and behaviour indicates that we should expect to find universal systems of perception, classification, and decision-making regarding the natural world. It is the interaction between these evolved aspects of the human mind, the biodiversity of the natural world, and unique historical, social, and economic contexts within which individuals develop and act that gives rise to cultural diversity. The palaeoanthropological record also indicates that language is a recently evolved phenomenon. This suggests that linguistic approaches in ethnobiology are likely to provide only a partial understanding of how humans perceive, classify, and engage with the natural world.
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This paper provides some preliminary insights into the emergence and development of indigenous general contractors in Ghana. General contracting is the means by which an individual or organisation takes responsibility for supplying all of the materials, labour, equipment and services necessary for the construction of a project. Whereas the development of general contracting in places like the UK is well documented, the evolution of contractors in Ghana is not clearly articulated in the literature. Therefore, the main question in this paper is: How did indigenous contractors evolve in Ghana? To examine and analyze the research question, a literature review on similar developments elsewhere was first carried out. This was followed by discussions and unstructured interviews with experienced construction practitioners in Ghana most of whom were Quantity Surveyors. Most interviewees narrated their knowledge of contractor development in Ghana dating back to around 1945. From the explanations given, it was possible to develop a general understanding of the research question and to make a qualitative interpretation of the respondents’ comments and to draw some conclusions. General contractors emerged rapidly in the Gold Coast (now Ghana) shortly after World War II. Most were Italian master craftsmen in Ghana who were capitalized by the British colonial government to develop infrastructure in the Gold Coast following devastating effects of the war. Some of the indigenous people learned from the Italians and also established construction firms. Thus, general contracting in Ghana has a relatively short history in comparison to countries like Britain where the profession developed rapidly in the early part of the 19th century in response to the industrial revolution. Although they may possess sufficient technical expertise, many indigenous contractors in Ghana today lack the capacity to carry out major projects because of low capitalization and poor organisational structures. The current construction market in Ghana is dominated by foreign contractors. To become major players in the market, indigenous Ghanaian contractors should build strong organisational structures and pursue mergers and joint venturing to boost their financial, technical and managerial capacity.
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Latin had no word for "strategy", but the East Romans, whom we call the Byzantines, did. This book tracks the evolution of the concept of warfare being subjected to higher political aims from Antiquity to the Present, using Greek, Latin, French, Spanish, Italian, English and German sources. It tracks the rise, fall, and resurrection of the belief in the Roman and later the medieval and early modern world that warfare was only legitimate if it pursued the higher goal of a just peace, which in the 19th century gave way to a blinkered concentration on military victory as only war aim. It explains why one school of thought, from Antiquity to the present, emphasised eternal principles of warfare, while others emphasised, in Clausewitz's term, the "changing character of war". It tracks ideas from land warfare to naval warfare to air power and nuclear thinking, but it also stresses great leaps and discontinuities in thinking about strategy. It covers asymmetric wars both from the point of view of the weaker power seeking to overthrow a stronger power, and from the stronger power dealing with insurgents and other numerically inferior forces. It concludes with a commentary of the long-known problems of bureaucratic politics, non-centralised command and inter-service rivalry, which since the 16th century or earlier has created obstacles to coherent strategy making.
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Morphological integration refers to the modular structuring of inter-trait relationships in an organism, which could bias the direction and rate of morphological change, either constraining or facilitating evolution along certain dimensions of the morphospace. Therefore, the description of patterns and magnitudes of morphological integration and the analysis of their evolutionary consequences are central to understand the evolution of complex traits. Here we analyze morphological integration in the skull of several mammalian orders, addressing the following questions: are there common patterns of inter-trait relationships? Are these patterns compatible with hypotheses based on shared development and function? Do morphological integration patterns and magnitudes vary in the same way across groups? We digitized more than 3,500 specimens spanning 15 mammalian orders, estimated the correspondent pooled within-group correlation and variance/covariance matrices for 35 skull traits and compared those matrices among the orders. We also compared observed patterns of integration to theoretical expectations based on common development and function. Our results point to a largely shared pattern of inter-trait correlations, implying that mammalian skull diversity has been produced upon a common covariance structure that remained similar for at least 65 million years. Comparisons with a rodent genetic variance/covariance matrix suggest that this broad similarity extends also to the genetic factors underlying phenotypic variation. In contrast to the relative constancy of inter-trait correlation/covariance patterns, magnitudes varied markedly across groups. Several morphological modules hypothesized from shared development and function were detected in the mammalian taxa studied. Our data provide evidence that mammalian skull evolution can be viewed as a history of inter-module parcellation, with the modules themselves being more clearly marked in those lineages with lower overall magnitude of integration. The implication of these findings is that the main evolutionary trend in the mammalian skull was one of decreasing the constraints to evolution by promoting a more modular architecture.
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The thesis focuses on, and tries to evaluate, the role that the African Union (AU) plays in protecting the peace and security on the African continent. The thesis takes an interdisciplinary approach to the topic by both utilizing international relations and international law theories. The two disciplines are combined in an attempt to understand the evolution of the AU’s commitment to the pragmatist doctrine: responsibility to protect (R2P). The AU charter is considered to be the first international law document to cover R2P as it allows the AU to interfere in the internal affairs of its member states. The R2P doctrine was evolved around the notion of a need to arrive at a consensus in regard to the right to intervene in the face of humanitarian emergencies. A part of the post-Cold War shift in UN behaviour has been to support local solutions to local problems. Hereby the UN acts in collaboration with regional organizations, such as the AU, to achieve the shared aspirations to maintain international peace and security without getting directly involved on the ground. The R2P takes a more holistic and long-term approach to interventions by including an awareness of the need to address the root causes of the crisis in order to prevent future resurrections of conflicts. The doctrine also acknowledges the responsibility of the international community and the intervening parties to actively participate in the rebuilding of the post-conflict state. This requires sustained and well planned support to ensure the development of a stable society.While the AU is committed to implementing R2P, many of the AU’s members are struggling, both ideologically and practically, to uphold the foundations on which legitimate intervention rests, such as the protection of human rights and good governance. The fact that many members are also among the poorest countries in the world adds to the challenges facing the AU. A lack of human and material resources leads to a situation where few countries are willing, or able, to support a long-term commitment to humanitarian interventions. Bad planning and unclear mandates also limit the effectiveness of the interventions. This leaves the AU strongly dependent on regional powerbrokers such as Nigeria and South Africa, which in itself creates new problems in regard to the motivations behind interventions. The current AU charter does not provide sufficient checks and balances to ensure that national interests are not furthered through humanitarian interventions. The lack of resources within the AU also generates worries over what pressure foreign nations and other international actors apply through donor funding. It is impossible for the principle of “local solutions for local problems? to gain ground while this donor conditionality exists.The future of the AU peace and security regime is not established since it still is a work in progress. The direction that these developments will take depends on a wide verity of factors, many of which are beyond the immediate control of the AU.
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Includes bibliography
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Includes bibliography
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Includes bibliography