Evaluation of historic, current and future water demand in the Olifants River Catchment, South Africa

Poverty / Mapping

Earth Occultation Imaging of the Low Energy Gamma-Ray Sky with GBM

The Earth Occultation Technique (EOT) has been applied to Fermi's Gamma-ray Burst Monitor (GBM) to perform all-sky monitoring for a predetermined catalog of hard X-ray/soft gamma-ray sources. In order to search for sources not in the catalog, thus completing the catalog and reducing a source of systematic error in EOT, an imaging method has been developed -- Imaging with a Differential filter using the Earth Occultation Method (IDEOM). IDEOM is a tomographic imaging method that takes advantage of the orbital precession of the Fermi satellite. Using IDEOM, all-sky reconstructions have been generated for ~sim 4 years of GBM data in the 12-50 keV, 50-100 keV and 100-300 keV energy bands in search of sources otherwise unmodeled by the GBM occultation analysis. IDEOM analysis resulted in the detection of 57 sources in the 12-50 keV energy band, 23 sources in the 50-100 keV energy band, and 7 sources in the 100-300 keV energy band. Seventeen sources were not present in the original GBM-EOT catalog and have now been added. We also present the first joined averaged spectra for four persistent sources detected by GBM using EOT and by the Large Area Telescope (LAT) on Fermi: NGC 1275, 3C 273, Cen A, and the Crab

The Poincare-Birkhoff theorem in Quantum Mechanics

Quantum manifestations of the dynamics around resonant tori in perturbed Hamiltonian systems, dictated by the Poincar\'e--Birkhoff theorem, are shown to exist. They are embedded in the interactions involving states which differ in a number of quanta equal to the order of the classical resonance. Moreover, the associated classical phase space structures are mimicked in the quasiprobability density functions and their zeros.Comment: 5 pages, 3 figures, Full resolution figures available at http://www.df.uba.ar/users/wisniaki/publications.htm

Maximum population transfer in a periodically driven two-level system

We study the dynamics of a two-level quantum system under the influence of sinusoidal driving in the intermediate frequency regime. Analyzing the Floquet quasienergy spectrum, we find combinations of the field parameters for which population transfer is optimal and takes place through a series of well defined steps of fixed duration. We also show how the corresponding evolution operator can be approximated at all times by a very simple analytical expression. We propose this model as being specially suitable for treating periodic driving at avoided crossings found in complex multi-level systems, and thus show a relevant application of our results to designing a control protocol in a realistic molecular modelComment: 7 pages, 6 figure

Extended X-ray emission around RRAT J1819-1458

We present new imaging and spectral analysis of the recently discovered extended X-ray emission around the high-magnetic-field rotating radio transient RRAT J1819-1458. We used two Chandra observations, taken on 2008 May 31 and 2011 May 28. The diffuse X-ray emission was detected with a significance of ~19sigma in the image obtained by combining the two observations. Long-term spectral variability has not been observed. Possible scenarios for the origin of this diffuse X-ray emission, further detailed in Camero-Arranz et al. (2012), are here discussed.Comment: Proceedings of IAUS 291 "Neutron Stars and Pulsars: Challenges and Opportunities after 80 years", J. van Leeuwen (ed.); 4 pages, 3 figure

Economic feasibility analysis of choices for not connected clients: photovoltaic off-grid systems, compared to grid based system

Off-grid photovoltaic systems are less constrained by national regulations than their grid-connected counterparts. Off-grid systems do not depend on feed-in tariff and the analysis of their cost-efficiency is more stable along time. This work calculates the economic parameters for two different technologies of photovoltaic systems and compares the levelized cost of electricity (LCOE), with the price of the electricity, including the cost for the connection of the system related to the distance to the grid. The results show that the sustained decline in photovoltaic module¿s price contributes to subsequent decline in LCOE, whereas the increase in the price of grid electricity and materials related to the connection makes off-grid systems more cost-effective for remote areas. Finally, to determine if the photovoltaic system could be an economic alternative for investments in remote regions, a comparison between the cost of grid extension and the LCOE of a high capacity photovoltaic system was undertaken

The development of a resource-efficient photovoltaic system

This paper presents the measures taken in the demonstration of the photovoltaic case study developed within the European project ‘Towards zero waste in industrial networks’ (Zerowin), integrating the D4R (Design for recycling, repair, refurbishment and reuse) criteria at both system and industrial network level. The demonstration is divided into three phases. The first phase concerns the development of a D4R photovoltaic concept, the second phase focused on the development of a specific component of photovoltaic systems and the third phase was the demonstration of the D4R design in two complete photovoltaic systems (grid-connected and stand-alone). This paper includes a description of the installed photovoltaic systems, including a brief summary at component level of the lithium ion battery system and the D4R power conditioning system developed for the pilot installations. Additionally, industrial symbioses within the network associated with the photovoltaic systems and the production model for the network are described

Colgajo de vasto lateral de pedículo distal para cobertura de lesiones complejas de rodilla

El tratamiento de las heridas complejas articulares se muestra siempre complicado, el abordaje razonable conjunto por traumatólogos y cirujanos plásticos mejora el resultado clínico, funcional y estético. Presentamos el caso de un paciente politraumatizado con pérdida de sustancia a nivel de la rodilla secundaria a artritis séptica, necrosis de patela y exposición de cóndilos femorales que fue tratado mediante colgajo muscular de vastus lateralis de pedículo distal. El vastus lateralis permite la cobertura eficiente de l articulación expuesta sin afectar la extensión de la rodilla y dejando mínima secuela estética.The treatment of the joint complex wounds is difficult. A good clinic, functional and aesthetic outcome is possible when multidisciplinary approach by orthopaedics and plastic surgeons is carried out. We report a case of a patient with multiple fractures who presents a severe loss of soft tissue at the knee. This lesion was due to a septic arthritis with patellar necrosis and condillar exposition. The treatment was made by a distally pedicled vastus lateralis muscular flap. This flap lets efficient coverage for the exposed joint as well as the integrity of the extensión knee function without aesthetic seque