Gravitational entropy and thermodynamics away from the horizon
- Authors: Brustein, R , Medved, A J M
- Date: 2012
- Language: English
- Type: Article
- Identifier: vital:6818 , http://hdl.handle.net/10962/d1004328
- Description: We define, by an integral of geometric quantities over a spherical shell of arbitrary radius, an invariant gravitational entropy. This definition relies on defining a gravitational energy and pressure, and it reduces at the horizon of both black branes and black holes to Wald's Noether charge entropy. We support the thermodynamic interpretation of the proposed entropy by showing that, for some cases, the field theory duals of the entropy, energy and pressure are the same as the corresponding quantities in the field theory. In this context, the Einstein equations are equivalent to the field theory thermodynamic relation TdS=dE+PdV supplemented by an equation of state
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- Date Issued: 2012
Freshwater invertebrate fauna of the Tristan da Cunha islands (South Atlantic Ocean), with new records for Inaccessible and Nightingale Islands
- Authors: Barber-James, Helen Margaret
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6940 , http://hdl.handle.net/10962/d1011964
- Description: As part of a multidisciplinary floristic-faunistic study, a three week survey of the invertebrate fauna of Inaccessible Island (South Atlantic Ocean) was carried out in October / November 1989. In addition, one day of collecting was done on Nightingale Island. This paper deals only with the fauna associated with freshwater ecosystems from these islands, some of which are usually associated with marine or brackish conditions. On Inaccessible Island, five distinct types of freshwater body were identified - pH neutral streams, acidic streams (pH 5), an open pool of standing water (pH 6), areas of acidic bog, and seepages down rock faces. The survey, the most comprehensive for Inaccessible Island to date, has resulted in the discovery of 19 aquatic invertebrate species previously unrecorded on Inaccessible Island, two new to Nightingale Island, and 14 of which are new to the Tristan da Cunha archipelago. Many of the species are known from other parts of the world, indicating a low degree of endemicity within the freshwater invertebrate community. Recolonisation from the source populations, preventing an isolated gene pool, may account for the low endemicity. Several of the species have a degree of salinity tolerance, enabling them to withstand transportation across tracts of ocean, and others have marine origins.
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- Date Issued: 2007
Multivariate morphometric analysis of Apis cerana of southern mainland Asia
- Authors: Hepburn, H Randall , Radloff, Sarah E , Hepburn, Colleen , Fuchs, S , Otis, G W , Sein, M M , Aung, H L , Pham, H T , Tam, D Q , Nuru, A M , Ken, T
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6906 , http://hdl.handle.net/10962/d1011859
- Description: Multivariate morphometric analyses were performed on a series of worker honeybees, Apis cerana, representing 557 colonies from all of southern mainland Asia extending from Afghanistan to Vietnam south of the Himalayas. Scores from the principal components analysis revealed five statistically separable but not entirely distinct morphoclusters of bees: (1) the Hindu Kush, Kashmir, N. Myanmar, N. Vietnam and S. China; (2) Himachal Pradesh region of N. India; (3) N. India, Nepal; (4) central and S. Myanmar and Vietnam, Cambodia, Thailand, S. China and peninsular Malaysia; (5) central and S. India. The major morphoclusters are distributed coherently with the different climatic zones of the region. While populations are definable, nomenclatural adjustments remain for the future.
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- Date Issued: 2005
Trans-oceanic and endemic origins of the small minnow mayflies (Ephemeroptera, Baetidae) of Madagascar
- Authors: Monaghan, M T , Gattolliat, J L , Sartori, Michel , Elouard, J M , Barber-James, Helen M , Derleth, P , Glaizot, Olivier , de Moor, Ferdy C , Vogler, Alfred P
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6957 , http://hdl.handle.net/10962/d1011998
- Description: We investigated the relative importance of dispersal and vicariance in forming the Madagascar insect fauna, sequencing approximately 2300bp from three rRNA gene regions to investigate the phylogeny of Afrotropical small minnow mayflies (Ephemeroptera: Baetidae). Six lineages contained trans-oceanic sister taxa, and variation in genetic divergence between sister taxa revealed relationships that range from very recent dispersal to ancient vicariance. Dispersal was most recent and frequent in species that spend the larval stage in standing water, adding to evidence that these evolutionarily unstable habitats may select for ecological traits that increase dispersal in insects. Ancestral state likelihood analysis suggested at least one Afrotropical lineage had its origin in Madagascar, demonstrating that unidirectional dispersal from a continental source may be too simplistic. We conclude that the Malagasy mayfly fauna should be considered in a biogeographical context that extends beyond Madagascar itself, encompassing trans-oceanic dispersal within multiple lineages.
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- Date Issued: 2005