Bounds on the local energy density of holographic CFTs from bulk geometry

The stress tensor is a basic local operator in any field theory; in the context of AdS/CFT, it is the operator which is dual to the bulk geometry itself. Here we exploit this feature by using the bulk geometry to place constraints on the local energy density in static states of holographic $(2+1)$-dimensional CFTs living on a closed (but otherwise generally curved) spatial geometry. We allow for the presence of a marginal scalar deformation, dual to a massless scalar field in the bulk. For certain vacuum states in which the bulk geometry is well-behaved at zero temperature, we find that the bulk equations of motion imply that the local energy density integrated over specific boundary domains is negative. In the absence of scalar deformations, we use the inverse mean curvature flow to show that if the CFT spatial geometry has spherical topology but non-constant curvature, the local energy density must be positive somewhere. This result extends to other topologies, but only for certain types of vacuum; in particular, for a generic toroidal boundary, the vacuum's bulk dual must be the zero-temperature limit of a toroidal black hole.Comment: 14+2 pages, 2 figures. v2: fixed equations (51) and (52

Nuclear mutations affecting mitochondrial structure and function in Chlamydomonas

Wild type cells of the green alga Chlamydomonas reinhardtii can grow in the in the dark by taking up and respiring exogenously supplied acetate. Obligate photoautotrophic (dark dier, dk) mutants of this alga have been selected which grow at near wild type rates in the light, but rapidly die when transferred to darkness because of defects in mitochondrial structure and function. In crosses of the dk mutants to wild type, the majority of the mutants are inherited in a mendelian fashion, although two have been isolated which are inherited in a clearly nonmendelian fashion. Nine mendelian dk mutants have been analyzed in detail, and belong to eight different complementation groups representing eight gene loci. These mutants have been tentatively grouped into three classes on the basis of the pleiotropic nature of their phenotypic defects. Mutants in Class I have gross alterations in the ultrastructure of their mitochondrial inner membranes together with deficiencies in cytochrome oxidase and antimycin/rotenone-sensitive NADH-cytochrome c reductase activities. Mutants in Class II have a variety of less severe alterations in mitochondrial ultrastructure and deficiencies in cytochrome oxidase activity. Mutants in Class III have normal or near normal mitochondrial ultrastructure and reduced cytochrome oxidase activity. Eight of the nine mutants show corresponding reductions in cyanide-sensitive respiration

From spoken word to digital corpus : The Calum Maclean project

The Calum Maclean Collection (http://www.calum-maclean-project.celtscot.ed.ac.uk) is a searchable, standards-based catalog of a collection of Scottish Gaelic oral narrative that was developed between 2005 and 2009 with major research funding from the Arts and Humanities Research Council (AHRC, http://www.ahrc.ac.uk). It is one of a series of projects begun early in the past decade to make folklore materials in Scotland more widely available to the public through the usage of digital technology. Implicit in such initiatives has been the intention to develop multiple social applications of archived folklore materials; during such development, two primary aspects of the technological applications have been a wider promotion of folklore materials through technology and the enhancement of Scotland's main folklore archives.Not

Chasing the deer: hunting iconography, literature and tradition of the Scottish Highlands

Hunting inspired some of the greatest songs and stories of Gaelic literature and tradition—a theme which runs from the earliest Old Irish sources down to the literature of Modern Scottish Gaelic. This thesis examines the cultural history of hunting in the Scottish Highlands stemming from the late-medieval period through to the early modern. The three main areas covered are the iconography, literature and tradition of the chase.Many hunting topoi appear upon late-medieval west Highland sculptures, remarkably similar to those on earlier Pictish sculpture, which are complimented by the Gaelic literature and lore of hunting contained within Fenian ballads and narrative stories. The apogee of Gaelic hunting motifs are contained within panegyric poetry and verse of the 16th, 17th and 18th centuries, sustained in the main by a late manifestation of an heroic age. Such imagery reinforced and perpetuated the identity of the chief as the paragon of pre-modern Gaelic society, who was always seen as a hunter-warrior. Hunting themes and motifs are also prevalent within Gaelic folksong tradition. Although this overlaps in terms of content with the bardic imagery of professional poets, the vernacular folksongs offer a more emotive and direct response to moments of crisis or celebration. The scale of these great hunts in the Highlands, borne out by the literary evidence, from the medieval period onwards, reflects a complex matrix of power, patronage, politics and ultimately propaganda. As well as being a surrogate for war the tinchel, in Gaelic terms, was a seasonal mobilising of the sluagh, or host, who followed the fine, the Gaelic nobility. This enhanced their status while reinforcing clan solidarity in a shared symbol of sporting endeavour, by chasing the noble quarry of the deer. Notable, also, is illegal, or covert hunting which masked a complex deer-culture, and marked the familiar tension of exploiting natural resources by the many against the privileged few who tried to implement their inherited rights to hunt. Inevitably, superstition pervades much of the traditions of the hunt, as it would in any given belief system centred upon age-old customs.Hunting was an integral part of European culture, and it was a theme reflected in Gaelic literature, song, and tradition more evidently than in many other European cultures of a comparable period. This was because it reinforced strongly and perpetuated the idealised image of a warrior-hunter, the archetypal leader engendered within Gaelic cultural identity