5,336 research outputs found

    Phylogenetic relationships of African Caecilians (Amphibia: Gymnophiona): insights from mitochondrial rRNA gene sequences

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    Africa (excluding the Seychelles) has a diverse caecilian fauna, including the endemic family Scolecomorphidae and six endemic genera of the more cosmopolitan Caeciliidae. Previous molecular phylogenetic studies have not included any caecilians from the African mainland. Partial 12S and 16S mitochondrial gene sequences were obtained for two species of the endemic African Scolecomorphidae and five species and four genera of African Caeciliids, aligned against previously reported sequences for 16 caecilian species, and analysed using parsimony, maximum likelihood, Bayesian and distance methods. Results are in agreement with traditional taxonomy in providing support for the monophyly of the African Caeciliid genera Boulengerula and Schistometopum and for the Scolecomorphidae. They disagree in indicating that the Caeciliidae is paraphyletic with respect to the Scolecomorphidae. Although more data from morphology and/or molecules will be required to resolve details of the interrelationships of the African caecilian genera, the data provide strong support for at least two origins of caecilians in which the eye is reduced and covered with bone, and do not support the hypotheses that the caecilian assemblages of Africa, and of East and of West Africa are monophyletic

    The horofunction boundary of the Hilbert geometry

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    We investigate the horofunction boundary of the Hilbert geometry defined on an arbitrary finite-dimensional bounded convex domain D. We determine its set of Busemann points, which are those points that are the limits of `almost-geodesics'. In addition, we show that any sequence of points converging to a point in the horofunction boundary also converges in the usual sense to a point in the Euclidean boundary of D. We prove that all horofunctions are Busemann points if and only if the set of extreme sets of the polar of D is closed in the Painleve-Kuratowski topology.Comment: 24 pages, 2 figures; minor changes, examples adde

    Revision of the African caecilian genus Schistometopum Parker (Amphibia: Gymnophiona: Caeciliidae)

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    http://deepblue.lib.umich.edu/bitstream/2027.42/56430/4/MP187.pd

    Intergenerational justice of what: welfare, resources or capabilities?

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    An important aspect of intergenerational justice concerns the specification of a 'currency of advantage' that can be used to evaluate distributive outcomes across time. Environmental theorists have introduced several innovative currencies of justice in recent years, such as ecological space and critical natural capital. However they have often downplayed the application of established currencies (such as welfare, resources or capabilities) to issues of futurity. After exploring the merits of a number of rival currencies, it is argued that the currency of 'capabilities to function' provides a promising basis for a theory of justice that takes seriously the rights and duties of intergenerational justice

    Existence of positive solutions of a superlinear boundary value problem with indefinite weight

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    We deal with the existence of positive solutions for a two-point boundary value problem associated with the nonlinear second order equation u+a(x)g(u)=0u''+a(x)g(u)=0. The weight a(x)a(x) is allowed to change its sign. We assume that the function g ⁣:[0,+[Rg\colon\mathopen{[}0,+\infty\mathclose{[}\to\mathbb{R} is continuous, g(0)=0g(0)=0 and satisfies suitable growth conditions, so as the case g(s)=spg(s)=s^{p}, with p>1p>1, is covered. In particular we suppose that g(s)/sg(s)/s is large near infinity, but we do not require that g(s)g(s) is non-negative in a neighborhood of zero. Using a topological approach based on the Leray-Schauder degree we obtain a result of existence of at least a positive solution that improves previous existence theorems.Comment: 12 pages, 4 PNG figure

    Ten myths about character, virtue and virtue education – plus three well-founded misgivings

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    Initiatives to cultivate character and virtue in moral education at school continue to provoke sceptical responses. Most of those echo familiar misgivings about the notions of character, virtue and education in virtue – as unclear, redundant, old-fashioned, religious, paternalistic, anti-democratic, conservative, individualistic, relative and situation dependent. I expose those misgivings as ‘myths’, while at the same time acknowledging three better-founded historical, methodological and practical concerns about the notions in question

    Virtue and austerity

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    Virtue ethics is often proposed as a third way in health-care ethics, that while consequentialism and deontology focus on action guidelines, virtue focuses on character; all three aim to help agents discern morally right action although virtue seems to have least to contribute to political issues, such as austerity. I claim: (1) This is a bad way to characterize virtue ethics. The 20th century renaissance of virtue ethics was first proposed as a response to the difficulty of making sense of ‘moral rightness’ outside a religious context. For Aristotle the right action is that which is practically best; that means best for the agent in order to live a flourishing life.There are no moral considerations besides this. (2) Properly characterized, virtue ethics can contribute to discussion of austerity. A criticism of virtue ethics is that fixed characteristics seem a bad idea in ever-changing environments; perhaps we should be generous in prosperity, selfish in austerity. Furthermore, empirical evidence suggests that people indeed do change with their environment. However, I argue that virtues concern fixed values not fixed behaviour; the values underlying virtue allow for different behaviour in different circumstances: in austerity, virtues still give the agent the best chance of flourishing. Two questions arise. (a) In austere environments might not injustice help an individual flourish by, say, obtaining material goods? No, because unjust acts undermine the type of society the agent needs for flourishing. (b) What good is virtue to those lacking the other means to flourish? The notion of degrees of flourishing shows that most people would benefit somewhat from virtue. However, in extreme circumstances virtue might harm rather than benefit the agent: such circumstances are to be avoided; virtue ethics thus has a political agenda to enable flourishing. This requires justice, a fortiori when in austerity

    An archaeology of borders: qualitative political theory as a tool in addressing moral distance

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    Interviews, field observations and other qualitative methods increasingly are being used to inform the construction of arguments in normative political theory. This article works to demonstrate the strong salience of some kinds of qualitative material for cosmopolitan arguments to extend distributive boundaries. The incorporation of interviews and related qualitative material can make the moral claims of excluded others more vivid and possibly more difficult to dismiss by advocates of strong priority to compatriots in distributions. Further, it may help to promote the kind of perspective taking that has been associated with actually motivating a willingness to aid by individuals. Illustrative findings are presented from field work conducted for a normative project on global citizenship, including interviews with unauthorized immigrants and the analysis of artifacts left behind on heavily used migrant trails

    Linguistic incompetence: giving an account of researching multilingually

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    This paper considers the place of linguistic competence and incompetence in the context of researching multilingually. It offers a critique of the concept of competence and explores the performative dimensions of multilingual research and its narration, through the philosophy of Judith Butler, and in particular her study Giving an account of oneself. It explores aspects of risk, justice, narrative limit and a morality of multilingualism in emergent multilingual research frameworks. These theoretical dimensions are explored through consideration of ‘linguistically incompetent’ ethnographic work with refugees and asylum seekers, in contexts of hospitality and in life long learning research in the Gaza Strip, and of early attempts to learn new languages. The paper offers a prospect of a relational approach to researching multilingually and affirms the vulnerability at the heart of linguistic hospitality
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