855 resultados para dominant discourse


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* Although plants can reduce the impacts of herbivory in multiple ways, these defensive traits are often studied in isolation and an understanding of the resulting strategies is incomplete. * In the study reported here, empirical evidence was simultaneously evaluated for the three main sets of traits available to plants: (i) resistance through constitutive leaf traits, (ii) tolerance to defoliation and (iii) escape in space, for three caesalpiniaceous tree species Microberlinia bisulcata, Tetraberlinia bifoliolata and T. korupensis, which co-dominate groves within the lowland primary rain forest of Korup National Park (Cameroon). * Mesh cages were placed around individual wild seedlings to exclude insect herbivores at 41 paired canopy gap and understorey locations. After following seedling growth and survival for c. 2 years, caged and control treatments were removed, leaves harvested to determine nutrient and phenolic concentrations, leaf mass per area estimated, and seedling performance in gaps followed for a further c. 2 years to quantify tolerance to the leaf harvesting. * The more nutrient-rich leaves of the weakly shade-tolerant M. bisulcata were damaged much more in gaps than the two strongly shade-tolerant Tetraberlinia species, which had higher leaf mass per area and concentrations of total phenols. Conversely, the faster-growing M. bisulcata was better able to tolerate defoliation in terms of height growth (reflushing capacity), but not at maintaining overall leaf numbers, than the other two species. * Across gaps, insect-mediated Janzen–Connell effects were most pronounced for M. bisulcata, less so for T. korupensis, and not detectable for T. bifoliolata. The three species differed distinctly in their secondary metabolic profiles. * Taken together, the results suggested a conceptual framework linking the three sets of traits, one in which the three co-dominant species adopt different strategies towards herbivore pressure depending on their different responses to light availability. This study is one of the first in a natural forest ecosystem to examine resistance to, tolerance of, and escape from herbivory among a group of co-occurring tropical tree species.

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Seed production, seed dispersal, and seedling recruitment are integral to forest dynamics, especially in masting species. Often these are studied separately, yet scarcely ever for species with ballistic dispersal even though this mode of dispersal is common in legume trees of tropical African rain forests. Here, we studied two dominant main-canopy tree species, Microberlinia bisulcata and Tetraberlinia bifoliolata (Caesalpinioideae), in 25 ha of primary rain forest at Korup, Cameroon, during two successive masting events (2007/2010). In the vicinity of c. 100 and 130 trees of each species, 476/580 traps caught dispersed seeds and beneath their crowns c. 57,000 pod valves per species were inspected to estimate tree-level fecundity. Seed production of trees increased non-linearly and asymptotically with increasing stem diameters. It was unequal within the two species’ populations, and differed strongly between years to foster both spatial and temporal patchiness in seed rain. The M. bisulcata trees could begin seeding at 42–44 cm diameter: at a much larger size than could T. bifoliolata (25 cm). Nevertheless, per capita life-time reproductive capacity was c. five times greater in M. bisulcata than T. bifoliolata owing to former’s larger adult stature, lower mortality rate (despite a shorter life-time) and smaller seed mass. The two species displayed strong differences in their dispersal capabilities. Inverse modelling (IM) revealed that dispersal of M. bisulcata was best described by a lognormal kernel. Most seeds landed at 10–15 m from stems, with 1% of them going beyond 80 m (<100 m). The direct estimates of fecundity significantly improved the models fitted. The lognormal also described well the seedling recruitment distribution of this species in 121 ground plots. By contrast, the lower intensity of masting and more limited dispersal of the heavier-seeded T. bifoliolata prevented reliable IM. For this species, seed density as function of distance to traps suggested a maximum dispersal distance of 40–50 m, and a correspondingly more aggregated seedling recruitment pattern ensued than for M. bisulcata. From this integrated field study, we conclude that the reproductive traits of M. bisulcata give it a considerable advantage over T. bifoliolata by better dispersing more seeds per capita to reach more suitable establishment sites, and combined with other key traits they explain its local dominance in the forest. Understanding the linkages between size at onset of maturity, individual fecundity, and dispersal capability can better inform the life-history strategies, and hence management, of co-occurring tree species in tropical forests.

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As the continuing relevance of religion to secular European societies garners increasing recognition, the question remains of which religious positions may assume a public role, with Islam at the center of many debates. This article complements the ongoing theoretical debate with a detailed case study analyzing the major works of Islamic scholar and public intellectual Tariq Ramadan. I show that in the last two decades Ramadan significantly modified his views on Islam and European societies. I argue that these adjustments were interdependent, and as such paradigmatically illustrate that the integration of Islamic positions into public discourse depends on shifts in the understanding of both concepts.

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The paper is a comparative inquiry into the roles of Ilia Chavchavadze (1837-1907) and Taras Shevchenko (1818-1861) as national poets and anti-colonial (anti-Tsarist) intellectuals within the context of their respective national traditions (Georgia and Ukraine). During the period of their activity (19th and the beginning of 20th century) both Ukraine and Georgia were under Tsarist imperial rule, albeit the two poets lived in different periods of Russian empire history. Through their major works, each called on their communities to ‘awaken’ and ‘revolt’ against oppression, rejected social apathy caused by Tsarist subjugation and raised awareness about the historical past of their nations. The non-acceptance of present and belief in an independent future was one of the dominant themes in the poetry and prose of both. Their contemporary importance is illustrated in political discourse both after Orange Revolution in Ukraine (2004), and Rose Revolution in Georgia (2003) where both poets are referred “as founding fathers of national ideology”, the history textbooks alluding to them as “symbols of anti-colonial resistance”. To this day, however, there has been surprisingly little academic writing in the West endeavoring to compare the works and activities of the two poets and their impact on national mobilization in Tsarist Ukraine and Georgia, even though their countries are often mentioned in a same breath by commentators on contemporary culture and politics. The paper attempts to fill this gap and tries to understand the relationship between literature and social mobilization in 19th century Russian Empire. By reflecting on Taras Shevchenko’s and Ilia Chavchavadze’s poetry, prose and social activism, I will try to explain how in different periods of Russian imperial history, the two poets helped to develop a modern form of political belonging among their compatriots and stimulated an anti-colonial mobilization with different political outcomes. To theorize on the role of poets and novelists in anti-colonial national movement, I will reflect on the writings of Benedict Anderson (1991), John Hutchinson (1994; 1999), Rory Finnin (2005; 2011) and problematize Miroslav Hroch’s (1996) three phase model of the development of national movements. Overall, the paper would aim to show the importance of, what John Hutchinson called, ‘cultural nationalists’ in understanding contemporary nationalist discourse in Georgian and Ukrainian societies.

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This paper will focus on three episodes of contemporary church-state relations in Georgia, in particular, the conflicting interaction between law and religion in the public space. The first episode will be an open confrontation between the church and the state over the law on Registration of Religious Minority organizations (2011) which allowed the religious minorities to freely register; second: the Law on Self-governance (2013) which Georgian Orthodox Church considered “a threat to territorial integrity of Georgia”; and lastly: the Law on Anti-discrimination (2014) which was deemed “legitimization of Sodomic sin”. By reflecting on the three examples where for the first time after the collapse of Soviet Union, the Georgian state openly confronted the church and made a decision notwithstanding its position, I will attempt to argue that the role of the Orthodox Church in influencing the law making process is in gradual decline. However, on the other hand, by presenting the results of an ethnographic study conducted in 23 eparchies and perishes in 7 regions of Georgia in 2014, I will also show that church has adapted to its declining role over policy making, and to regain its political influence it gradually started to employ a civic rather than ethno nationalist discourse on matters of religious freedom while engaging with government. The paper will suggest that both unilateral decision-making of the state and civic shift in the discourse of the church constitute an important change in understanding church-state dynamics in the post-communist Orthodox Christianity dominated society.

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White spotting phenotypes have been intensively studied in horses, and although similar phenotypes occur in the donkey, little is known about the molecular genetics underlying these patterns in donkeys. White spotting in donkeys can range from only a few white areas to almost complete depigmentation and is characterised by a loss of pigmentation usually progressing from a white spot in the hip area. Completely white-born donkeys are rare, and the phenotype is characterised by the complete absence of pigment resulting in pink skin and a white coat. A dominant mode of inheritance has been demonstrated for spotting in donkeys. Although the mode of inheritance for the completely white phenotype in donkeys is not clear, the phenotype shows similarities to dominant white in horses. As variants in the KIT gene are known to cause a range of white phenotypes in the horse, we investigated the KIT gene as a potential candidate gene for two phenotypes in the donkey, white spotting and white. A mutation analysis of all 21 KIT exons identified a missense variant in exon 4 (c.662A>C; p.Tyr221Ser) present only in a white-born donkey. A second variant affecting a splice donor site (c.1978+2T>A) was found exclusively in donkeys with white spotting. Both variants were absent in 24 solid-coloured controls. To the authors' knowledge, this is the first study investigating genetic mechanisms underlying white phenotypes in donkeys. Our results suggest that two independent KIT alleles are probably responsible for white spotting and white in donkeys.

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Under the name Nollywood a unique video film industry has developed in Nigeria in the last few decades, which now forms one of the world’s biggest entertainment industries. With its focus on stories reflecting „the values, desires and fears” (Haynes 2007: 133) of African viewers and its particular way of production, Nollywood brings „lived practices and its representation together in ways that make the films deeply accessible and entirely familiar to their audience“ (Marston et al. 2007: 57). In doing so, Nollywood shows its spectators new postcolonial forms of performative self‐expression and becomes a point of reference for a wide range of people. However, Nollywood not only excites a large number of viewers inside and outside Nigeria, it also inspires some of them to become active themselves and make their own films. This effect of Nigerian filmmaking can be found in many parts of sub‐Saharan Africa as well as in African diasporas all over the world – including Switzerland (Mooser 2011: 63‐66). As a source of inspiration, Nollywood and its unconventional ways of filmmaking offer African migrants a benchmark that meets their wish to express themselves as minority group in a foreign country. As Appadurai (1996: 53), Ginsburg (2003: 78) and Marks (2000: 21) assume, filmmakers with a migratory background have a specific need to express themselves through media. As minority group members in their country of residence they not only wish to reflect upon their situation within the diaspora and illustrate their everyday struggles as foreigners, but to also express their own views and ideas in order to challenge dominant public opinion (Ginsburg 2003: 78). They attempt to “talk back to the structures of power” (2003: 78) they live in. In this process, their audio-visual works become a means of response and “an answering echo to a previous presentation or representation” (Mitchell 1994: 421). The American art historian Mitchell, therefore, suggests interpreting representation as “the relay mechanism in exchange of power, value, and publicity” (1994: 420). This desire of interacting with the local public has also been expressed during a film project of African, mainly Nigerian, first-generation migrants in Switzerland I am currently partnering in. Several cast and crew members have expressed feelings of being under-represented, even misrepresented, in the dominant Swiss media discourse. In order to create a form of exchange and give themselves a voice, they consequently produce a Nollywood inspired film and wish to present it to the society they live in. My partnership in this on‐going film production (which forms the foundation of my PhD field study) allows me to observe and experience this process. By employing qualitative media anthropological methods and in particular Performance Ethnography, I seek to find out more about the ways African migrants represent themselves as a community through audio‐visual media and the effect the transnational use of Nollywood has on their form of self‐representations as well as the ways they express themselves.