409 research outputs found

    Holonomy and submanifold geometry

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    We survey applications of holonomic methods to the study of submanifold geometry, showing the consequences of some sort of extrinsic version of de Rham decomposition and Berger's Theorem, the so-called Normal Holonomy Theorem. At the same time, from geometric methods in submanifold theory we sketch very strong applications to the holonomy of Lorentzian manifolds. Moreover we give a conceptual modern proof of a result of Kostant for homogeneous space

    Restoration practices in Mediterranean habitats using native woody species

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    Since the beginning of the XXI century, Legambiente (a national environmental association), supported by the University of Palermo, has launched several naturalization projects within three Sicilian nature reserves: 1)Isola di Lampedusa (Agrigento Province); 2)Macalube di Aragona (Agrigento Province); 3)Lago Sfondato (Caltanissetta Province). Interventions were carried out on bare lands and degraded sites where natural vegetation cover was almost completely disappeared. The main aim was to restore native habitats following the principles of ecological restoration. Accordingly, differently from the classical approach, consisting in the use of preparatory species, usually Pines, native shrubs and trees were selected and used in the field

    Emergenze vegetali dell'Isola di Lampedusa

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    Per la peculiarit\ue0 storica, geografica ed ambientale l\u2019Isola di Lampedusa, e vista l\u2019estrema frammentariet\ue0 delle formazioni preforestali, l\u2019esiguit\ue0 dei popolamenti (e degli individui) delle specie legnose assumono un valore scientifico e conservazionistico particolarmente elevato. Per queste ragioni \ue8 stato fatto un censimento eseguito con strumentazione GPS. Sull\u2019isola crescono diverse specie di rilevante interesse conservazionistico, numerose sono infatti le specie endemiche, esclusive, rare e/o a rischio di estinzione perch\ue9 legate a habitat molto vulnerabili e localizzati. A questa ragione d\u2019interesse generale per questi taxa si somma il fatto che buona parte delle specie arboree tipiche della vegetazione primaria dell\u2019isola, il pi\uf9 delle volte sopravvivono localmente con popolamenti costituiti da pochissimi (e talora singoli!) individui. Juniperus turbinata e Olea europaea var. sylvestris sono le due specie forestali di gran lunga pi\uf9 comuni tra quelle indagate . Meno positivo \ue8 il risultato dell\u2019analisi della rinnovazione, che ha permesso di individuare appena una trentina di giovani individui di ginepro e nessuno di olivastro. La presenza delle due specie sull\u2019isola risulta circoscritta esclusivamente ai valloni stretti ed incisi che sboccano sulla costa meridionale dell\u2019isola, disegnando un complesso sistema in cui si alternano profonde insenature e pendii rocciosi subpianeggianti. Per ambedue le specie si \ue8 registrata una netta prevalenza (ca. 80% dei ginepri e ca. 95% degli olivastri!) in corrispondenza delle esposizioni meridionali dell\u2019isola che, sebbene pi\uf9 soleggiate godono dell\u2019effetto benefico dei venti umidi provenienti da meridione

    Restoration practices in Mediterranean habitats using native woody species

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    Since the beginning of the XXI century, Legambiente (a national environmental association), supported by the University of Palermo, has launched several naturalization projects within three Sicilian nature reserves: 1)Isola di Lampedusa (Agrigento Province); 2)Macalube di Aragona (Agrigento Province); 3)Lago Sfondato (Caltanissetta Province). Interventions were carried out on bare lands and degraded sites where natural vegetation cover was almost completely disappeared. The main aim was to restore native habitats following the principles of ecological restoration. Accordingly, differently from the classical approach, consisting in the use of preparatory species, usually Pines, native shrubs and trees were selected and used in the field

    Holonomy and submanifold geometry

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    We survey applications of holonomic methods to the study of submanifold geometry, showing the consequences of some sort of extrinsic version of de Rham decomposition and Berger's Theorem, the so-called Normal Holonomy Theorem. At the same time, from geometric methods in submanifold theory we sketch very strong applications to the holonomy of Lorentzian manifolds. Moreover we give a conceptual modern proof of a result of Kostant for homogeneous spaces

    Global Ethics and Postcolonial Lucifers

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    This dissertation unites four literary accounts from four different parts of the world under the concept of extraterritorial literature - literature by and about exile. Salman Rushdie’s The Satanic Verses (India-England, 1988); Abdulrazak Gurnah’s Admiring Silence (Zanzibar-England, 1996); Jamaica Kincaid’s Lucy (Antigua-US, 1990); and Hector Tobar’s The Tattooed Soldier (Guatemala-US, 1998) are brought together under the claim that transnational, extraterritorial literature is not a superior discourse but a momentous analysis of contemporary imperialism. A central argument in this dissertation is that writers who cross borders and who relocate from formerly colonized places to imperial metropolitan centers in the West use the transgressive figure of the exile, an unaccommodated, resistant other, in order to provide immanent critique -- to put histories, cultures, and ideologies face to face. This literary figure helps us understand that the alliance with people not only of the same kind but fundamentally different from us is necessary in reaching the real height of the self that exile promotes. The dialectic of the imperial mind – the Western fascination with the exotic other, the European Project of describing itself by way of describing the colonized; and also the dialectic of the colonized mind – that which has become “parasitically obsessed” with the West as a colonial power, are central terms to this project. The social and literary subjects that this dialectic produces must be seen in relation to an ideology of hope surrounding the exiled secular intellectual whose role is to promote a democratic ideal. Through these postcolonial Luciferic characters, the authors offer a meditation on global ethics, a cosmopolitan discourse that is not only necessary but also inevitable in today’s age of increased multiculturalism
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