Geometry of Higher-Dimensional Black Hole Thermodynamics

We investigate thermodynamic curvatures of the Kerr and Reissner-Nordstr\"om (RN) black holes in spacetime dimensions higher than four. These black holes possess thermodynamic geometries similar to those in four dimensional spacetime. The thermodynamic geometries are the Ruppeiner geometry and the conformally related Weinhold geometry. The Ruppeiner geometry for $d=5$ Kerr black hole is curved and divergent in the extremal limit. For $d \geq 6$ Kerr black hole there is no extremality but the Ruppeiner curvature diverges where one suspects that the black hole becomes unstable. The Weinhold geometry of the Kerr black hole in arbitrary dimension is a flat geometry. For RN black hole the Ruppeiner geometry is flat in all spacetime dimensions, whereas its Weinhold geometry is curved. In $d \geq 5$ the Kerr black hole can possess more than one angular momentum. Finally we discuss the Ruppeiner geometry for the Kerr black hole in $d=5$ with double angular momenta.Comment: 8 pages, 2 figures, RevTex, References adde

PERSPECTIVA SOBRE O SENTIDO DO TRABALHO PARA CATADORES DE MATERIAL RECICLÁVEL EM DUAS ASSOCIAÇÕES NA CIDADE DE XANXERÊ

O avanço tecnocientífico a partir do século XVIII intensificou o uso dos recursos naturais para convertê-los em bens de consumo pela sociedade, gerando um crescente acúmulo de materiais descartados pela não possibilidade de consumo. Os materiais descartados, se não reutilizados, acarretarão sérios danos ambientais e humanos. Portanto, a necessidade de se trabalhar com esses materiais levou um grupo de marginalizados socialmente a se apropriarem deles e inseri-los de volta à sociedade. Esse grupo social é visto como um descarte humano pela sociedade, comprometendo o papel do Estado, que é o de assegurar os direitos civis, fundamentais à vida a toda a sociedade. Portanto, na Cidade de Xanxerê, um grupo de catadores de materiais recicláveis vem realizando o trabalho de coleta e reciclagem desses materiais descartados pela sociedade local. Assim, nesta pesquisa teve-se por objetivo verificar o sentido do trabalho para os catadores de material reciclável na Sociedade Contemporânea, considerada de consumo, geradora de material descartável. Adotou-se como metodologia a pesquisa de campo qualitativa, em que se aplicou um questionário fechado e um questionário aberto a 15 catadores de materiais recicláveis. Os resultados obtidos permitiram saber que o sentido do trabalho para esses trabalhadores tem um viés político e ecológico.Palavras-chave: Trabalho. Sentido do trabalho. Dignidade da pessoa humana

Decellularized aortic conduits: could their cryopreservation affect post-implantation outcomes? A morpho-functional study on porcine homografts

Decellularized porcine aortic valve conduits (AVCs) implanted in a Vietnamese Pig (VP) experimental animal model were matched against decellularized and then cryopreserved AVCs to assess the effect of cryopreservation on graft hemodynamic performance and propensity to in vivo repopulation by host\u2019s cells. VPs (n = 12) underwent right ventricular outflow tract substitution using AVC allografts and were studied for 15-month follow-up. VPs were randomized into two groups, receiving AVCs treated with decellularization alone (D; n = 6) or decellularization/cryopreservation (DC; n = 6), respectively. Serial echocardiography was carried out to follow up hemodynamic function. All explanted AVCs were processed for light and electron microscopy. No signs of dilatation, progressive stenosis, regurgitation, and macroscopic calcification were echocardiographically observed in both D and DC groups. Explanted D grafts exhibited near-normal features, whereas the presence of calcification, inflammatory infiltrates, and disarray of elastic lamellae occurred in some DC grafts. In the unaltered regions of AVCs from both groups, almost complete re-endothelialization was observed for both valve cusps and aorta walls. In addition, side-by-side repopulation by recipient\u2019s fibroblasts, myofibroblasts, and smooth muscle cells was paralleled by ongoing tissue remodeling, as revealed by the ultrastructural identification of typical canals of collagen fibrillogenesis and elastogenesis-related features. Incipient neo-vascularization and re-innervation of medial and adventitial tunicae of grafted aortic walls were also detected for both D and DC groups. Cryopreservation did not affect post-implantation AVC hemodynamic behavior and was topically propensive to cell repopulation and tissue renewal, although graft deterioration including calcification was present in several areas. Thus, these preliminary data provide essential information on feasibility of decellularization and cryopreservation coupling in the perspective of treatment optimization and subsequent clinical trials using similarly treated human allografts as innovative heart valve substitutes

An exploratory study into the role and interplay of intrinsic and extrinsic cues in Australian consumers’ evaluations of fish.

This study explores the role and interplay of intrinsic and extrinsic cues when evaluating fish quality and in shaping consumers' attitudes toward fish consumption. A sensory analysis of nine different fish including five variants of barramundi was conducted to determine how consumers evaluated the fish on intrinsic cues. Focus groups were then conducted to explore the impact of extrinsic cues on attitudes and purchase intentions. While the sensory analysis revealed distinct differences between barramundi variants on intrinsic cues (notably taste), the focus groups revealed that, as a brand, barramundi is perceived much more favourably and consistently. Consumers used extrinsic cues, particularly country of origin, as surrogate indicators of quality. Aquaculture producers need to ensure intrinsic product quality and consistency, as while consumers use the extrinsic cue of "Australian grown" as a surrogate indicator of quality, as their familiarity and confidence with seafood grows, this overreliance on extrinsic cues may diminish

A Massive Open Online Course on Particle Accelerators

International audienceThe TIARA (Test Infrastructure and Accelerator Research Area) project funded by the European Union 7th framework programme made a survey of provision of education and training in accelerator science in Europe. This survey highlighted the need for more training opportunities targeting undergraduate-level students. This need is now being addressed by the European Union H2020 project ARIES (Accelerator Research and Innovation for European Science and Society) via the preparation of a Massive Online Open Course (MOOC) on particle accelerator science and engineering. We present here the current status of this project, the main elements of the syllabus, how it will be delivered, and the schedule for providing the course