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Maiga A.I.,Unite Technologies
Journal of acquired immune deficiency syndromes (1999) | Year: 2012

Mutations in the connection domain (CD) of reverse transcriptase have been implicated in reverse transcriptase inhibitor (RTI) resistance, but this is controversial and little is known in non-B subtype HIV-1. We determined CD mutations prevalence in a population infected predominantly with CRF02_AG and investigated associations with phenotypic RTI resistance. Detected CD mutations were G335D (82.3%), A371V (69.8%), E399D (9.4%), N348I (5.2%), V365I (4.2), Y318F (2.1%), G333E (2.1%), and A360V (2.1%). Mutations were largely polymorphic and did not confer RTI resistance. The observed trend toward reduced likelihood of etravirine or nevirapine resistance in the presence of G335D should be investigated further. Source

Fritzsche K.,Adelphi | Zejli D.,Unite Technologies | Tanzler D.,Adelphi
Energy Policy | Year: 2011

Global climate and energy governance have led to the creation of a wide range of international and regional institutions, initiatives and financial mechanisms dedicated to fostering renewable energies. Furthermore, a low-carbon economy has evolved in recent years. The objective of this paper is to assess the potential benefits and merits of these institutions, initiatives and mechanisms from the perspective of the Middle East and North Africa (MENA) region. The central questions are if and how these organizations, initiatives and finance mechanisms could support a country from MENA in its efforts to implement large-scale capacities for renewable energy production. For this purpose, Morocco was chosen as a case study. The findings in this paper indicate that the existing institutions and financial mechanisms do not sum up to a coordinated governance approach, although the main needs of a country or region appear to be addressed. The existing institutions and financial mechanisms vary significantly in their ability to support countries, especially those taking the lead in renewable energy implementation. © 2010 Elsevier Ltd. Source

Farr W.G.,University of Western Australia | Creedon D.L.,University of Western Australia | Goryachev M.,University of Western Australia | Benmessai K.,Unite Technologies | Tobar M.E.,University of Western Australia
Physical Review B - Condensed Matter and Materials Physics | Year: 2013

Progress in the emerging field of engineered quantum systems requires the development of devices that can act as quantum memories. The realization of such devices by doping solid-state cavities with paramagnetic ions imposes a tradeoff between ion concentration and cavity coherence time. Here, we investigate an alternative approach involving interactions between photons and naturally occurring impurity ions in ultrapure crystalline microwave cavities exhibiting exceptionally high quality factors. We implement a hybrid whispering gallery/electron spin resonance method to perform rigorous spectroscopy of an undoped single-crystal sapphire resonator over the frequency range 8-19 GHz, and at external applied DC magnetic fields up to 0.9 T. Measurements of high-purity sapphire cooled close to 100 mK reveal the presence of Fe3+, Cr3+, and V2+ impurities. A host of electron transitions are measured and identified, including the two-photon classically forbidden quadrupole transition (Δms=2) for Fe3+, as well as hyperfine transitions of V2+. © 2013 American Physical Society. Source

Brand B.,Wuppertal Institute for Climate | Boudghene Stambouli A.,University of Science and Technology of Oran | Zejli D.,Unite Technologies
Energy Policy | Year: 2012

This paper examines the effects of an increased integration of concentrated solar power (CSP) into the conventional electricity systems of Morocco and Algeria. A cost-minimizing linear optimization tool was used to calculate the best CSP plant configuration for Morocco's coal-dominated power system as well as for Algeria, where flexible gas-fired power plants prevail. The results demonstrate that in both North African countries, storage-based CSP plants offer significant economic advantages over non-storage, low-dispatchable CSP configurations. However, in a generalized renewable integration scenario, where CSP has to compete with other renewable generation technologies, like wind or photovoltaic (PV) power, it was found that the cost advantages of dispatchability only justify CSP investments when a relatively high renewable penetration is targeted in the electricity mix. © 2012 Elsevier Ltd. Source

Dagdougui H.,University of Genoa | Dagdougui H.,MINES ParisTech | Minciardi R.,University of Genoa | Ouammi A.,Unite Technologies | And 2 more authors.
Energy Conversion and Management | Year: 2012

Renewable energy sources (RES) are an "indigenous" environmental option, economically competitive with conventional power generation where good wind and solar resources are available. Hybrid systems can help in improving the economic and environmental sustainability of renewable energy systems to fulfill the energy demand. The aim of this paper is to present a dynamic model able to integrate different RES and one storage device to feed a "Green" building for its thermal and electrical energy needs in a sustainable way. The system model is embedded in a dynamic decision model and is used to optimize a quite complex hybrid system connected to the grid which can exploit different renewable energy sources. A Model Predictive Control (MPC) is adopted to find the optimal solution. The optimization model has been applied to a case study where electric energy is also used to pump water for domestic use. Optimal results are reported for two main cases: the presence/absence of the energy storage system. © 2012 Elsevier Ltd. All rights reserved. Source

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