The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Abdus Salam - One of the best experts on this subject based on the ideXlab platform.
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United Nations Educational scientific and cultural organization and international atomic energy agency the abdus salam international centre for theoretical physics electrified plasma in ads cft correspondence
2010Co-Authors: Bindusar Sahoo, Houng Yee, Abdus SalamAbstract:We construct new gravity backgrounds holographic dual to neutral plasma with U(1) global symmetry in the presence of constant electric field, considering its full back-reactions to the metric. As the electric field and the induced current cause a net energy in-flow to the system, the plasma is continually heated up and the corresponding gravity solution has an expanding horizon. After proposing a consistent late-time expansion scheme, we present analytic solutions in the scheme up to next-leading order, and our solutions are new time-dependent solutions of 5D asymptotic AdS Einstein-Maxwell(-Chern-Simons) theory. To extract dual CFT stress tensor and U(1) current from the solutions, we perform a rigorous holographic renormalization of Einstein-Maxwell-Chern-Simons theory including full back-reactions, which can in itself be an interesting addition to literatures. As by-products, we obtain interesting modifications of energy-momentum/current Ward identities due to the U(1) symmetry and its triangle anomaly.
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United Nations Educational scientific and cultural organization and international atomic energy agency the abdus salam international centre for theoretical physics s matrix for magnons in the d1 d5 system
2010Co-Authors: Justin R David, Bindusar Sahoo, Abdus SalamAbstract:We show that integrability and symmetries of the near horizon geometry of the D1-D5 system determine the S-matrix for the scattering of magnons in this system completely up to a phase. Using semi-classical methods we evaluate the phase to the leading and to the one-loop approximation in the strong coupling expansion. We then show that the phase obeys the unitarity constraint implied by the crossing relations to the one-loop order. We also verify that the dispersion relation obeyed by these magnons is one-loop exact at strong coupling which is consistent with their BPS nature.
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United Nations Educational scientific and cultural organization and international atomic energy agency the abdus salam international centre for theoretical physics electromagnetic nucleon to delta transition
2009Co-Authors: Hovhannes R Grigoryan, Houng Yee, T S H Lee, Abdus SalamAbstract:We study nucleon-to-delta electromagnetic transition form factors and relations between them within the framework of holographic dual model of QCD proposed by Sakai and Sugimoto. In this setup, baryons appear as topological solitons of the five dimensional holographic gauge theory that describes a tower of mesons and their interactions. We find a relativistic extension of the nucleon-delta-vector meson interaction vertices and using these calculate transition form factors from holographic QCD. We observe that at low momentum transfer, magnetic dipole, electric and Coulomb quadrupole form factors and their ratios follow the patterns expected in the large Nc limit. Our results at this approximation are in reasonable agreement with experiment.
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United Nations Educational scientific and cultural organization and international atomic energy agency the abdus salam international centre for theoretical physics holographic chiral shear waves from anomaly
2009Co-Authors: Keunyoung Kim, Houng Yee, Bindusar Sahoo, Abdus SalamAbstract:We present holographic computations of the time-dependent chiral magnetic conductivity in the framework of gauge/gravity correspondence. Chiral magnetic effect is a phenomenon where an electromagnetic current parallel to an applied magnetic field is induced in the presence of a finite axial chemical potential. Motivated by a recent weak-coupling perturbative QCD calculation, our aim is to provide a couple of complementary computations for strongly coupled regime which might be relevant for strongly coupled RHIC plasma. We take two prototypical holographic set-ups for computing chiral magnetic conductivity; the first model is Einstein gravity with U(1)L ×U(1)R Maxwell theory, and our second set-up is based on the Sakai-Sugimoto model in a deconfined and chiral symmetry restored phase. While the former takes into account full backreaction while the latter not, the common feature is an important role played by the appropriate 5-dimensional Chern-Simons term corresponding to the 4-dimensional axial anomaly.
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United Nations Educational scientific and cultural organization and international atomic energy agency the abdus salam international centre for theoretical physics phenomenology of flavon fields at the lhc
2009Co-Authors: Koji Tsumura, Liliana Velascosevilla, Abdus SalamAbstract:We study low energy constraints from flavour violating processes, production and decay at the LHC of a scalar field ϕ (flavon) associated to the breaking of a non supersymmetric Abelian family symmetry at the TeV scale. This symmetry is constrained to reproduce fermion masses and mixing, up to O(1) coefficients. The non-supersymmetric gaugedU(1) models considered are severely restricted by cancellation of anomalies and LEP bounds on contact interactions, consequently its phenomenology is out of the LHC reach. We therefore introduce an effective U(1) which is not gauged and it is broken explicitly by a CP odd term at the TeV scale. This help us to explore flavour violating processes, production and decay at the LHC for these kind of light scalars. In this context we first study the constraints on the flavon mass and its vacuum expectation value from low energy flavour changing processes such as � → eγ. We find that a flavon of about mϕ . 150 GeV could be experimentally allowed. These kind of flavons could be significantly generated at the LHC via the gluon fusion mechanism and the single top production channel gu → tϕ. The
Marcos Nogueira Eberlin - One of the best experts on this subject based on the ideXlab platform.
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quantification of sterol and triterpenol biomarkers in sediments of the cananeia iguape estuarine lagoonal system brazil by uhplc ms ms
International Journal of Analytical Chemistry, 2016Co-Authors: Giovana Anceski Bataglion, Hector Henrique Ferreira Koolen, Rolf Roland Weber, Marcos Nogueira EberlinAbstract:Sterols and triterpenols present in sedimentary cores from 12 stations along the Cananeia-Iguape estuarine-lagoonal system were investigated by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Ten sterols and three triterpenols were identified and quantified, indicating both natural and anthropogenic sources. The relative distributions of sterol and triterpenol showed that the study area is submitted to organic matter (OM) from the Ribeira de Iguape River, seawater, surrounding vegetation, and plankton production. The contribution of these sources depends on the region of the estuarine-lagoonal system and the depth of sediment. Regarding anthropogenic sources, only the samples submitted to freshwater flow from the Ribeira de Iguape River presented concentration of coprostanol higher than the threshold value and diagnostic ratios, coprostanol/(coprostanol + cholestanol) and coprostanol/cholesterol, that indicate moderate contamination by domestic sewage in that area of the estuarine-lagoonal system. Therefore, the approach used herein identified the OM sources and its transport along the Cananeia-Iguape estuarine-lagoonal system (Brazil), which is a complex of lagoonal channels located in a United Nations Educational, Scientific and Cultural Organization (UNESCO) Biosphere Reserve.
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Quantification of Sterol and Triterpenol Biomarkers in Sediments of the Cananéia-Iguape Estuarine-Lagoonal System (Brazil) by UHPLC-MS/MS
Hindawi Limited, 2016Co-Authors: Giovana Anceski Bataglion, Hector Henrique Ferreira Koolen, Rolf Roland Weber, Marcos Nogueira EberlinAbstract:Sterols and triterpenols present in sedimentary cores from 12 stations along the Cananéia-Iguape estuarine-lagoonal system were investigated by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Ten sterols and three triterpenols were identified and quantified, indicating both natural and anthropogenic sources. The relative distributions of sterol and triterpenol showed that the study area is submitted to organic matter (OM) from the Ribeira de Iguape River, seawater, surrounding vegetation, and plankton production. The contribution of these sources depends on the region of the estuarine-lagoonal system and the depth of sediment. Regarding anthropogenic sources, only the samples submitted to freshwater flow from the Ribeira de Iguape River presented concentration of coprostanol higher than the threshold value and diagnostic ratios, coprostanol/(coprostanol + cholestanol) and coprostanol/cholesterol, that indicate moderate contamination by domestic sewage in that area of the estuarine-lagoonal system. Therefore, the approach used herein identified the OM sources and its transport along the Cananéia-Iguape estuarine-lagoonal system (Brazil), which is a complex of lagoonal channels located in a United Nations Educational, Scientific and Cultural Organization (UNESCO) Biosphere Reserve
Donatella Saccone - One of the best experts on this subject based on the ideXlab platform.
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multilateralism and unesco world heritage decision making states parties and political processes
International Journal of Heritage Studies, 2015Co-Authors: Lynn Meskell, Claudia Liuzza, Enrico Bertacchini, Donatella SacconeAbstract:Why have deliberations over World Heritage sites become such a volatile arena for the performance of international tensions, new political alliances and challenges to global cooperation? Across UN platforms, the failures of multilateralism are increasingly evident. We suggest that decision-making within the World Heritage Committee is no different given that politicisation is now rife throughout their deliberations. Specifically we ask how have multipolarity and fragmentation developed within United Nations Educational, Scientific and Cultural Organisation’s (UNESCO) World Heritage programme, an organisation dedicated to peace building, tolerance and mutual understanding and international co-operation? This paper examines trends from the last decade of UNESCO’s World Heritage Committee meetings, specifically the nomiNations of properties for inscription on the World Heritage List. Our findings suggest that the recommendations presented by UNESCO’s Advisory Bodies are increasingly at odds with the final de...
Giovana Anceski Bataglion - One of the best experts on this subject based on the ideXlab platform.
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quantification of sterol and triterpenol biomarkers in sediments of the cananeia iguape estuarine lagoonal system brazil by uhplc ms ms
International Journal of Analytical Chemistry, 2016Co-Authors: Giovana Anceski Bataglion, Hector Henrique Ferreira Koolen, Rolf Roland Weber, Marcos Nogueira EberlinAbstract:Sterols and triterpenols present in sedimentary cores from 12 stations along the Cananeia-Iguape estuarine-lagoonal system were investigated by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Ten sterols and three triterpenols were identified and quantified, indicating both natural and anthropogenic sources. The relative distributions of sterol and triterpenol showed that the study area is submitted to organic matter (OM) from the Ribeira de Iguape River, seawater, surrounding vegetation, and plankton production. The contribution of these sources depends on the region of the estuarine-lagoonal system and the depth of sediment. Regarding anthropogenic sources, only the samples submitted to freshwater flow from the Ribeira de Iguape River presented concentration of coprostanol higher than the threshold value and diagnostic ratios, coprostanol/(coprostanol + cholestanol) and coprostanol/cholesterol, that indicate moderate contamination by domestic sewage in that area of the estuarine-lagoonal system. Therefore, the approach used herein identified the OM sources and its transport along the Cananeia-Iguape estuarine-lagoonal system (Brazil), which is a complex of lagoonal channels located in a United Nations Educational, Scientific and Cultural Organization (UNESCO) Biosphere Reserve.
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Quantification of Sterol and Triterpenol Biomarkers in Sediments of the Cananéia-Iguape Estuarine-Lagoonal System (Brazil) by UHPLC-MS/MS
Hindawi Limited, 2016Co-Authors: Giovana Anceski Bataglion, Hector Henrique Ferreira Koolen, Rolf Roland Weber, Marcos Nogueira EberlinAbstract:Sterols and triterpenols present in sedimentary cores from 12 stations along the Cananéia-Iguape estuarine-lagoonal system were investigated by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Ten sterols and three triterpenols were identified and quantified, indicating both natural and anthropogenic sources. The relative distributions of sterol and triterpenol showed that the study area is submitted to organic matter (OM) from the Ribeira de Iguape River, seawater, surrounding vegetation, and plankton production. The contribution of these sources depends on the region of the estuarine-lagoonal system and the depth of sediment. Regarding anthropogenic sources, only the samples submitted to freshwater flow from the Ribeira de Iguape River presented concentration of coprostanol higher than the threshold value and diagnostic ratios, coprostanol/(coprostanol + cholestanol) and coprostanol/cholesterol, that indicate moderate contamination by domestic sewage in that area of the estuarine-lagoonal system. Therefore, the approach used herein identified the OM sources and its transport along the Cananéia-Iguape estuarine-lagoonal system (Brazil), which is a complex of lagoonal channels located in a United Nations Educational, Scientific and Cultural Organization (UNESCO) Biosphere Reserve
Leah S Horowitz - One of the best experts on this subject based on the ideXlab platform.
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rhizomic resistance meets arborescent assemblage unesco world heritage and the disempowerment of indigenous activism in new caledonia
Annals of the American Association of Geographers, 2016Co-Authors: Leah S HorowitzAbstract:This article draws on Deleuze and Guattari's concepts of arborescent and rhizomic assemblages to examine encounters between large-scale conservation and grassroots resistance to industry. I explore how the United Nations Educational, Scientific and Cultural Organization's (UNESCO) World Heritage listing of New Caledonia's reefs contributed to the demise of Rheebu Nuu, an indigenous activist group that had been targeting a multinational mining project. I also interrogate how an assemblage's form enables certain modalities of power while constraining others and how these differences in power modalities inform relationships between types of assemblages. Mistakenly expecting assistance in protecting their coral reef from mining impacts, Rheebu Nuu relinquished the coercive power inherent to their rhizomic form in favor of participation in UNESCO's arborescent structure via World Heritage “management committees”—a globally promoted, but locally inappropriate, comanagement diagram that targeted local fishing ac...
