Designing spatial correlation of quantum dots: towards self-assembled three-dimensional structures

Buried two-dimensional arrays of InP dots were used as a template for the lateral ordering of self-assembled quantum dots. The template strain field can laterally organize compressive (InAs) as well as tensile (GaP) self-assembled nanostructures in a highly ordered square lattice. High-resolution transmission electron microscopy measurements show that the InAs dots are vertically correlated to the InP template, while the GaP dots are vertically anti-correlated, nucleating in the position between two buried InP dots. Finite InP dot size effects are observed to originate InAs clustering but do not affect GaP dot nucleation. The possibility of bilayer formation with different vertical correlations suggests a new path for obtaining three-dimensional pseudocrystals.

Comparative phylogeography of Trypanosoma cruzi TCIIc: New hosts, association with terrestrial ecotopes, and spatial clustering

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Spatial load forecasting using a demand propagation approach

A method for spatial electric load forecasting using multi-agent systems, especially suited to simulate the local effect of special loads in distribution systems is presented. The method based on multi-agent systems uses two kinds of agents: reactive and proactive. The reactive agents represent each sub-zone in the service zone, characterizing each one with their corresponding load level, represented in a real number, and their relationships with other sub-zones represented in development probabilities. The proactive agent carry the new load expected to be allocated because of the new special load, this agent distribute the new load in a propagation pattern. The results are presented with maps of future expected load levels in the service zone. The method is tested with data from a mid-size city real distribution system, simulating the effect of a load with attraction and repulsion attributes. The method presents good results and performance. © 2011 IEEE.

Pricing of reactive power support provided by distributed generators in transmission systems

Distributed Generation, microgrid technologies, two-way communication systems, and demand response programs are issues that are being studied in recent years within the concept of smart grids. At some level of enough penetration, the Distributed Generators (DGs) can provide benefits for sub-transmission and transmission systems through the so-called ancillary services. This work is focused on the ancillary service of reactive power support provided by DGs, specifically Wind Turbine Generators (WTGs), with high level of impact on transmission systems. The main objective of this work is to propose an optimization methodology to price this service by determining the costs in which a DG incurs when it loses sales opportunity of active power, i.e, by determining the Loss of Opportunity Costs (LOC). LOC occur when more reactive power is required than available, and the active power generation has to be reduced in order to increase the reactive power capacity. In the optimization process, three objectives are considered: active power generation costs of DGs, voltage stability margin of the system, and losses in the lines of the network. Uncertainties of WTGs are reduced solving multi-objective optimal power flows in multiple probabilistic scenarios constructed by Monte Carlo simulations, and modeling the time series associated with the active power generation of each WTG via Fuzzy Logic and Markov Chains. The proposed methodology was tested using the IEEE 14 bus test system with two WTGs installed. © 2011 IEEE.

Neonatal anoxia in rats: hippocampal cellular and subcellular changes related to cell death and spatial memory

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Spatial epidemiology of American cutaneous leishmaniasis in a municipality of west Sao Paulo State, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The shadows of a ghost: a survey of canine leishmaniasis in Presidente Prudente and its spatial dispersion in the western region of São Paulo state, an emerging focus of visceral leishmaniasis in Brazil

Visceral leishmaniasis is an emerging zoonosis and its geographic distribution is restricted to tropical and temperate regions. Most of the individuals infected in Latin America are in Brazil. Despite the control measures that have been adopted, the disease is spreading throughout new regions of the country. Domestic dogs are involved in the transmission cycle and are considered to be the main epidemiologic reservoir of Leishmania infantum (syn. L. chagasi). Our aim was to determine the prevalence of canine leishmaniasis (CL) and Ehrlichiosis infection in Presidente Prudente as well as the spatial dispersion of the disease in the western region of São Paulo state. Dogs underwent clinical examination and symptoms related to CL were recorded. Anti- Leishmania antibodies were detected using ELISA, rK39-immunocromatographic tests (DPP), and an indirect fluorescent antibody test (IFAT). Anti-E. canis antibodies were detected by IFAT. A follow-up was conducted in dogs that were positive in the ELISA at the baseline study. Data on the spatial distribution of L. longipalpis and CL in São Paulo state were obtained from Brazilian public health agencies. Serum samples from 4547 dogs were analyzed. The seroprevalence of CL was 11.2 % by ELISA and 4.5 % by IFAT. In the follow-up, seroprevalence was 32.9 % by ELISA, 15.3 % by IFAT, 11.8 % by DPP test, and 66.5 % for E. canis. There was a significant positive association between Leishmania and E. canis infection (P < 0.0001). In the follow-up, clinical examinations revealed symptoms compatible with CL in 33.5 % of the dogs. L. longipalpis was found in 24 and CL in 15 counties of the Presidente Prudente mesoregion. The dispersion route followed the west frontier of São Paulo state toward Paraná state. Low CL and high ehrlichiosis prevalence rates were found in Presidente Prudente city. This emerging focus of CL is moving through the western region of São Paulo state toward the border of Paraná state. Integrated actions to fight the vector, parasites, infected dogs, and humans are needed to monitor the disease and implement strategies for epidemiologic control.