950 resultados para Primitive societies
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Retinoic acid (RA) signaling is important to normal development. However, the function of the different RA receptors (RARs)-RARα, RARβ, and RARγ-is as yet unclear. We have used wild-type and transgenic zebrafish to examine the role of RARγ. Treatment of zebrafish embryos with an RARγ-specific agonist reduced somite formation and axial length, which was associated with a loss of hoxb13a expression and less-clear alterations in hoxc11a or myoD expression. Treatment with the RARγ agonist also disrupted formation of tissues arising from cranial neural crest, including cranial bones and anterior neural ganglia. There was a loss of Sox 9-immunopositive neural crest stem/progenitor cells in the same anterior regions. Pectoral fin outgrowth was blocked by RARγ agonist treatment. However, there was no loss of Tbx-5-immunopositive lateral plate mesodermal stem/progenitor cells and the block was reversed by agonist washout or by cotreatment with an RARγ antagonist. Regeneration of the caudal fin was also blocked by RARγ agonist treatment, which was associated with a loss of canonical Wnt signaling. This regenerative response was restored by agonist washout or cotreatment with the RARγ antagonist. These findings suggest that RARγ plays an essential role in maintaining stem/progenitor cells during embryonic development and tissue regeneration when the receptor is in its nonligated state.
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This work was presented in part at the 8th International Conference on Finite Fields and Applications Fq^8 , Melbourne, Australia, 9-13 July, 2007.
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It is proved that there exists a bijection between the primitive ideals of the algebra of regular functions on quantum m × n-matrices and the symplectic leaves of associated Poisson structure.
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This article provides necessary and sufficient conditions for both of the Diophantine equations X^2 − DY^2 = m1 and x^2 − Dy^2 = m2 to have primitive solutions when m1 , m2 ∈ Z, and D ∈ N is not a perfect square. This is given in terms of the ideal theory of the underlying real quadratic order Z[√D].
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In October 2008, the 5th Environmental Management for Sustainable Universities (EMSU) international conference was held in Barcelona, Spain. It dealt with the need to rethink how our higher educational institutions are facing sustainability. This special issue has been primarily derived from contributions to that conference. This issue builds upon related academic international publications, which have analysed how to use the critical position of universities to accelerate their pace of working to help to make the transition to truly SUSTAINABLE SOCIETIES! This issue focus is on the ‘softer’ issues, such as changes in values, attitudes, motivations, as well as in curricula, societal interactions and assessments of the impacts of research. Insights derived from the interplay of the ‘softer’ issues with the ‘harder’ issues are empowering academic leaders to effectively use leverage points to make changes in operations, courses, curricula, and research. Those changes are being designed to help their students and faculty build resilient and sustainable societies within the context of climate change, the Decade of Education for Sustainable Development (DESD), and the UN Millennium Development Goals (MDGs). The overall systems approach presented by Stephens and Graham provides a structured framework to systematize change for sustainability in higher education, by stressing on the one hand the need for “learning to learn” and on the other hand by integrating leadership and cultural aspects. The “niche” level they propose for innovative interactions between practitioners such as EMSU is exemplary developed by all of the other documents in this special issue. To highlight some of the key elements of the articles in this issue, there are proposals for new educational methods based in sustainability science, a set of inspirational criteria for SD research activities, new course ranking and assessment methods and results of psychological studies that provide evidence that participatory approaches are the most effective way to change values within university members in order to facilitate the development and sharing of new sustainability norms.
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Peer reviewed
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Peer reviewed
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Non peer reviewed
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Peer reviewed
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Abstract This thesis examines one of the most sensitive challenges facing contemporary democracies: the accommodation of Muslim minorities in public institutions and services. It focuses on the field of education, and on two particular issues: the public funding of Islamic schools and the accommodation of Muslim needs in public secular schools. The analysis is based on an examination of outcomes in four jurisdictions that differ significantly in the level of accommodation that has emerged: England, Scotland, Ontario, and Quebec. I seek to explain why such variation in outcomes exists among these four cases. I draw on four bodies of literature to underpin the theoretical framework: historical institutionalism, political mobilization by civil society, political parties, and ideationalism. My argument can be summarized simply; historic church-state settlements, unique in each case, are the most important factor explaining the variation in outcomes in England, Scotland, Ontario, and Quebec. In some cases, the historic church-state template is incrementally adapted to accommodate Muslim minorities. In other cases, relatively little accommodation occurs and the path-dependent trajectory of church-state relations remains entrenched. While the historic church-state template is a necessary factor in the explanation, it does not fully account for the variation. For a more complete picture, I demonstrate that there are several additional key factors that also shape the outcomes: first, national identity and public attitudes towards immigration and immigrants; second, the extent of mobilization by political agents, such as civil society organizations and historic churches; and third, the response of political parties to demands by Muslims for institutional accommodation. Ultimately, I conclude that Muslims in these jurisdictions are receiving some accommodation, but the process is slow and partial. This thesis makes important theoretical and empirical contributions to the discussion of Muslim integration in liberal democratic states. First, a framework has yet to be developed that considers the theoretical implications of institutional accommodation of Muslims; I address this gap. Second, this research demonstrates the utility of historical institutionalism in explaining the adaptation of church-state templates to accommodate Muslims’ demands. Last, this study makes an original contribution by comparing the cases of England, Scotland, Ontario, and Quebec in the accommodation of Muslims in education. A comparison of Canada with the United Kingdom has not yet been done.
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This paper aims to analyse a sample of Galician co-ops to verify whether or not it is possible to deduce different financial behaviours among co-op partners from the amount of net-surplus. To this end, our study adds net-surplus to the variation registered in some account entries so that other residual incomes yielded by the co-op may be considered. The distribution of these revenues shows that partners do not usually choose to fully anticipate residual incomes. This reveals that some firms follow a positive net-surplus strategy, which is actually different from the null net-surplus strategy asserted by the classical financial theory. Furthermore, results show that differences between both strategies are statistically significant. This opens a path to future research on determinants explaining why co-op partners voluntarily renounce to anticipating these residual incomes. Such behaviour only arises when yearly accounts render a positive result, thereby making the accounting net-surplus a useful tool to analyse financial information in co-op societies.