30 resultados para primate reconciliation


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Sustainable development requires the reconciliation of demands for biodiversity conservation and increased agricultural production. Assessing the impact of novel farming practices on biodiversity and ecosystem services is fundamental to this process. Using farmland birds as a model system, we present a generic risk assessment framework that accurately predicts each species' current conservation status and population growth rate associated with past changes in agriculture. We demonstrate its value by assessing the potential impact on biodiversity of two controversial land uses, genetically modified herbicide-tolerant crops and agri-environment schemes. This framework can be used to guide policy and land management decisions and to assess progress toward sustainability targets.

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Education and ethnicity cannot be discussed without taking language into account. This paper will argue that any discussion of ethnic minorities cannot ignore the question of language, nor can any discussion of human rights ignore the question of language rights. Unfortunately, in today's globalised world, governments and minorities are faced with conflicting pressures: on the one hand, for the development and use of education in a global/international language; on the other for the use and development of mother tongue, local or indigenous languages in education. Language complexity and ethnic plurality were largely brought about as a result of the creation of nation-states, which were spread around the world as a result of European colonialism. European languages and formal education systems were used as a means of political and economic control. The legacy that was left by the colonial powers has complicated ethnic relations and has frequently led to conflict. While there is now greater recognition of the importance of language both for economic and educational development, as well as for human rights, the forces of globalisation are leading towards uniformity in the languages used, in culture and even in education. They are working against the development of language rights for smaller groups. We are witnessing a sharp decline in the number of languages spoken. Only those languages which are numerically, economically and politically strong are likely to survive. As a result many linguistic and ethnic groups are in danger of being further marginalised. This paper will illustrate this thesis both historically and from several contemporary societies, showing how certain policies have exacerbated ethnic conflict while others are seeking to promote harmony and reconciliation. Why this should be so will be explored. (c) 2006 Elsevier Ltd. All rights reserved.

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Saccadic eye movements and fixations are the behavioral means by which we visually sample text during reading. Human oculomotor control is governed by a complex neurophysiological system involving the brain stem, superior colliculus, and several cortical areas [1, 2]. A very widely held belief among researchers investigating primate vision is that the oculomotor system serves to orient the visual axes of both eyes to fixate the same target point in space. It is argued that such precise positioning of the eyes is necessary to place images on corresponding retinal locations, such that on each fixation a single, nondiplopic, visual representation is perceived [3]. Vision works actively through a continual sampling process involving saccades and fixations [4]. Here we report that during normal reading, the eyes do not always fixate the same letter within a word. We also demonstrate that saccadic targeting is yoked and based on a unified cyclopean percept of a whole word since it is unaffected if different word parts are delivered exclusively to each eye via a dichoptic presentation technique. These two findings together suggest that the visual signal from each eye is fused at a very early stage in the visual pathway, even when the fixation disparity is greater than one character (0.29 deg), and that saccade metrics for each eye are computed on the basis of that fused signal.

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Increasing rates of obesity have stimulated research into possible contributing factors, including specific dietary components such as trans fatty acids (TFAs). This review considers the evidence for an association between TFA intake and weight gain. It concludes that there is limited but consistent evidence from epidemiological studies, and from a primate model, that increased TFA consumption may result in a small additional weight gain. Data from a long-term study in a primate model suggest that TFA may have a greater adipogenic effect than cis monounsaturated fatty acids; however, there are currently inadequate mechanistic data to provide a comprehensive and plausible explanation for any such metabolic differences between the types of fatty acids.

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Automatically extracting interesting objects from videos is a very challenging task and is applicable to many research areas such robotics, medical imaging, content based indexing and visual surveillance. Automated visual surveillance is a major research area in computational vision and a commonly applied technique in an attempt to extract objects of interest is that of motion segmentation. Motion segmentation relies on the temporal changes that occur in video sequences to detect objects, but as a technique it presents many challenges that researchers have yet to surmount. Changes in real-time video sequences not only include interesting objects, environmental conditions such as wind, cloud cover, rain and snow may be present, in addition to rapid lighting changes, poor footage quality, moving shadows and reflections. The list provides only a sample of the challenges present. This thesis explores the use of motion segmentation as part of a computational vision system and provides solutions for a practical, generic approach with robust performance, using current neuro-biological, physiological and psychological research in primate vision as inspiration.

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It is thought that speciation in phytophagous insects is often due to colonization of novel host plants, because radiations of plant and insect lineages are typically asynchronous. Recent phylogenetic comparisons have supported this model of diversification for both insect herbivores and specialized pollinators. An exceptional case where contemporaneous plant insect diversification might be expected is the obligate mutualism between fig trees (Ficus species, Moraceae) and their pollinating wasps (Agaonidae, Hymenoptera). The ubiquity and ecological significance of this mutualism in tropical and subtropical ecosystems has long intrigued biologists, but the systematic challenge posed by >750 interacting species pairs has hindered progress toward understanding its evolutionary history. In particular, taxon sampling and analytical tools have been insufficient for large-scale co-phylogenetic analyses. Here, we sampled nearly 200 interacting pairs of fig and wasp species from across the globe. Two supermatrices were assembled: on average, wasps had sequences from 77% of six genes (5.6kb), figs had sequences from 60% of five genes (5.5 kb), and overall 850 new DNA sequences were generated for this study. We also developed a new analytical tool, Jane 2, for event-based phylogenetic reconciliation analysis of very large data sets. Separate Bayesian phylogenetic analyses for figs and fig wasps under relaxed molecular clock assumptions indicate Cretaceous diversification of crown groups and contemporaneous divergence for nearly half of all fig and pollinator lineages. Event-based co-phylogenetic analyses further support the co-diversification hypothesis. Biogeographic analyses indicate that the presentday distribution of fig and pollinator lineages is consistent with an Eurasian origin and subsequent dispersal, rather than with Gondwanan vicariance. Overall, our findings indicate that the fig-pollinator mutualism represents an extreme case among plant-insect interactions of coordinated dispersal and long-term co-diversification.

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The anatomical basis and adaptive function of the expansion in primate brain size have long been studied; however, we are only beginning to understand the genetic basis of these evolutionary changes. Genes linked to human primary microcephaly have received much attention as they have accelerated evolutionary rates along lineages leading to humans. However, these studies focus narrowly on apes, and the link between microcephaly gene evolution and brain evolution is disputed. We analyzed the molecular evolution of four genes associated with microcephaly (ASPM, CDK5RAP2, CENPJ, MCPH1) across 21 species representing all major clades of anthropoid primates. Contrary to prevailing assumptions, positive selection was not limited to or intensified along the lineage leading to humans. In fact we show that all four loci were subject to positive selection across the anthropoid primate phylogeny. We developed clearly defined hypotheses to explicitly test if selection on these loci was associated with the evolution of brain size. We found positive relationships between both CDK5RAP2 and ASPM and neonatal brain mass and somewhat weaker relationships between these genes and adult brain size. In contrast, there is no evidence linking CENPJ and MCPH1 to brain size evolution. The stronger association of ASPM and CDK5RAP2 evolution with neonatal brain size than with adult brain size is consistent with these loci having a direct effect on prenatal neuronal proliferation. These results suggest that primate brain size may have at least a partially conserved genetic basis. Our results contradict a previous study that linked adaptive evolution of ASPM to changes in relative cortex size; however, our analysis indicates that this conclusion is not robust. Our finding that the coding regions of two widely expressed loci has experienced pervasive positive selection in relation to a complex, quantitative developmental phenotype provides a notable counterexample to the commonly asserted hypothesis that cisregulatory regions play a dominant role in phenotypic evolution. Key words: ASPM, MCPH1, CDK5RAP2, CENPJ, brain, neurogenesis, primates.

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How can organizations use digital infrastructure to realise physical outcomes? The design and construction of London Heathrow Terminal 5 is analysed to build new theoretical understanding of visualization and materialization practices in the transition from digital design to physical realisation. In the project studied, an integrated software solution is introduced as an infrastructure for delivery. The analyses articulate the work done to maintain this digital infrastructure and also to move designs beyond the closed world of the computer to a physical reality. In changing medium, engineers use heterogeneous trials to interrogate and address the limitations of an integrated digital model. The paper explains why such trials, which involve the reconciliation of digital and physical data through parallel and iterative forms of work, provide a robust practice for realizing goals that have physical outcomes. It argues that this practice is temporally different from, and at times in conflict with, building a comprehensive dataset within the digital medium. The paper concludes by discussing the implications for organizations that use digital infrastructures in seeking to accomplish goals in digital and physical media.

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The question of what explains variation in expenditures on Active Labour Market Programs (ALMPs) has attracted significant scholarship in recent years. Significant insights have been gained with respect to the role of employers, unions and dual labour markets, openness, and partisanship. However, there remain significant disagreements with respects to key explanatory variables such the role of unions or the impact of partisanship. Qualitative studies have shown that there are both good conceptual reasons as well as historical evidence that different ALMPs are driven by different dynamics. There is little reason to believe that vastly different programs such as training and employment subsidies are driven by similar structural, interest group or indeed partisan dynamics. The question is therefore whether different ALMPs have the same correlation with different key explanatory variables identified in the literature? Using regression analysis, this paper shows that the explanatory variables identified by the literature have different relation to distinct ALMPs. This refinement adds significant analytical value and shows that disagreements are at least partly due to a dependent variable problem of ‘over-aggregation’.

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How does a society less than two decades after a liberation war which involved large sections of the population come to terms with the memories of violence and war — a war in which there was no clear distinction between insurgent and counter‐insurgent, liberator and oppressor and in which the majority of the casualties can be found among the rural civilian population? This was a predicament not exclusive to Zimbabwe, but one which also applies to Mozambique, South Africa and, more recently, to Rwanda. Since its independence Zimbabwe has been a prime example of successful reconciliation. Ranger has argued that spiritual healing has contributed importantly to coming to terms with the trauma of war through turning violence into history. Here it will be argued that an analysis of the intersections between memories of violence, healing, and history reveals a twofold process. Social healing is made possible by a shift from conviction and compensation to revealing without convicting. At the same time healing provides an arena for communities in which competing and contesting memories of violence are renegotiated. Through these processes sense is being made of the past; history is being made.

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Historical narratives help construct social identities, which are maintained through differentiation between in-groups and "others." In this article, we contend that Fatima Besnaci-Lancou's texts, as well as her reconciliation work—in which she enjoins Beurs and Harkis' offspring to write a new, inclusive, polyphonic narrative of the Algerian War—are an example of the positive use of textually mediated identity (re)construction. Her work suggests the possibility of implementing a moderate politics of empathetic recognition of the (often migration-related) memories of "others" so as to reinforce French national belongingness.

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Ancestral human populations had diets containing more indigestible plant material than present-day diets in industrialized countries. One hypothesis for the rise in prevalence of obesity is that physiological mechanisms for controlling appetite evolved to match a diet with plant fiber content higher than that of present-day diets. We investigated how diet affects gut microbiota and colon cells by comparing human microbial communities with those from a primate that has an extreme plant-based diet, namely, the gelada baboon, which is a grazer. The effects of potato (high starch) versus grass (high lignin and cellulose) diets on human-derived versus gelada-derived fecal communities were compared in vitro. We especially focused on the production of short-chain fatty acids, which are hypothesized to be key metabolites influencing appetite regulation pathways. The results confirmed that diet has a major effect on bacterial numbers, short-chain fatty acid production, and the release of hormones involved in appetite suppression. The potato diet yielded greater production of short-chain fatty acids and hormone release than the grass diet, even in the gelada cultures, which we had expected should be better adapted to the grass diet. The strong effects of diet on hormone release could not be explained, however, solely by short-chain fatty acid concentrations. Nuclear magnetic resonance spectroscopy found changes in additional metabolites, including betaine and isoleucine, that might play key roles in inhibiting and stimulating appetite suppression pathways. Our study results indicate that a broader array of metabolites might be involved in triggering gut hormone release in humans than previously thought. IMPORTANCE: One theory for rising levels of obesity in western populations is that the body's mechanisms for controlling appetite evolved to match ancestral diets with more low-energy plant foods. We investigated this idea by comparing the effects of diet on appetite suppression pathways via the use of gut bacterial communities from humans and gelada baboons, which are modern-day primates with an extreme diet of low-energy plant food, namely, grass. We found that diet does play a major role in affecting gut bacteria and the production of a hormone that suppresses appetite but not in the direction predicted by the ancestral diet hypothesis. Also, bacterial products were correlated with hormone release that were different from those normally thought to play this role. By comparing microbiota and diets outside the natural range for modern humans, we found a relationship between diet and appetite pathways that was more complex than previously hypothesized on the basis of more-controlled studies of the effects of single compounds.

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Families in market economies worldwide have long been confronted with the demands of participating in paid work and providing care for their dependent members. The social, economic and political contexts within which families do so differ from country to country but an increasing number of governments are being asked to engage, or better engage, with this important area of public policy. What seems like a relatively simple goal – to enable families to better balance care-giving and paid employment – has raised several difficulties and dilemmas for policy makers which have been approached in different ways. This paper aims to identify and critique the nature and development of the means by which legal engagement with work-family reconciliation has, historically, been framed in the European Union. In doing so, and with reference to specific cohorts of workers, we demonstrate how disjointed the strategies are in relation to working carers and argue that the EU is unlikely to provide the legal framework necessary to bring about effective change in this fundamentally important area of social policy.

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The human body occupies a central place in Rukeyser’s poetry. Her characters’ physical experiences inspire their search for an artistic form and a holistic vision that reconciles the corporeal and conceptual aspects of their life. My thesis deals with Rukeyser’s reconciliation of disparate aspects of existence through the image of the human body and the practical experiences she underwent in her personal life and incorporated in her poetry. I discuss her poetry of the 1940s, where a tension is observed between the artist’s personal life and her art, which she attempts to resolve by adopting an artistic form that accommodates her quotidian experiences. I study, mainly through her poetry of the 1950s, Rukeyser’s poetic technique in the light of her organicist poetics and the combination of tendencies to coercion and suggestiveness distinguishing her style. I examine her portrayal of the suffering body in her poetry of the 1960s and 1970s. By means of their physical experiences, the ill, her despised and the imprisoned protagonists undergo a process of development whereby they perceive the different aspects of their identity and attempt to broaden perspectives on their situation by reconciling them. I argue that Rukeyser’s engagement with physical encounters and with the poem as an inclusive, organic body enables her to reconcile disparate elements in her poetry, such as her personal life and her art, her individual existence and the public world, as well as the distinct aspects of her characters’ identity. Her vatic outlook, which integrates distinct aspects of experience, is consistent with Merleau-Ponty’s idea of human perception as characterised by the two interdependent positions of immanence and transcendence. Rukeyser’s poetry depicts her physical engagement with quotidian events of her life as a factor of artistic inspiration. These situations constitute shared human experiences that enable her to imagine the links binding her to other people and the world at large. The poet’s personal experiences inspire her search for an artistic form that accommodates them. Her perception of the concrete aspect of her individual existence gains significance when it is linked to social and political issues. Both the private and public are thus seen as interconnected, and they affect the existence of each other while retaining their distinctness.

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Rates of phenotypic evolution vary widely in nature and these rates may often reflect the intensity of natural selection. Here we outline an approach for detecting exceptional shifts in the rate of phenotypic evolution across phylogenies. We introduce a simple new branch-specific metric ∆V/∆B that divides observed phenotypic change along a branch into two components: (1) that attributable to the background rate (∆B), and (2) that attributable to departures from the background rate (∆V). Where the amount of expected change derived from variation in the rate of morphological evolution doubles that explained by to the background rate (∆V/∆B > 2), we identify this as positive phenotypic selection. We apply our approach to six datasets, finding multiple instances of positive selection in each. Our results support the growing appreciation that the traditional gradual view of phenotypic evolution is rarely upheld, with a more episodic view taking its place. This moves focus away from viewing phenotypic evolution as a simple homogeneous process and facilitates reconciliation with macroevolutionary interpretations from a genetic perspective, paving the way to novel insights into the link between genotype and phenotype. The ability to detect positive selection when genetic data are unavailable or unobtainable represents an attractive prospect for extant species, but when applied to fossil data it can reveal patterns of natural selection in deep time that would otherwise be impossible.