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We investigate optical transitions and carrier dynamics in hybrid structures containing type-I GaAs/AlGaAs quantum wells (QWs) and type-II GaSb/AlGaAs quantum dots (QDs). We show that the optical recombination of photocreated electrons confined in the QWs with holes in the QDs and wetting layer can be modified according to the QW/QD spatial separation. In particular, for low spacer thicknesses, the QW optical emission can be suppressed due to the transference of holes from the QW to the GaSb layer, favoring the optical recombination of spatially separated carriers, which can be useful for optical memory and solar cell applications. Time-resolved photoluminescence (PL) measurements reveal non-exponential recombination dynamics. We demonstrate that the PL transients can only be quantitatively described by considering both linear and quadratic terms of the carrier density in the bimolecular recombination approximation for type-II semiconductor nanostructures. We extract long exciton lifetimes from 700 ns to 5 μs for QDs depending on the spacer layer thickness. [ABSTRACT FROM AUTHOR]

Abstract Background Dengue is the most important arbovirus disease in tropical and subtropical countries. The viral envelope (E) protein is responsible for cell receptor binding and is the main target of neutralizing antibodies. The aim of this study was to analyze the diversity of the E protein gene of DENV-3. E protein gene sequences of 20 new viruses isolated in Ribeirao Preto, Brazil, and 427 sequences retrieved from GenBank were aligned for diversity and phylogenetic analysis. Results Comparison of the E protein gene sequences revealed the presence of 47 variable sites distributed in the protein; most of those amino acids changes are located on the viral surface. The phylogenetic analysis showed the distribution of DENV-3 in four genotypes. Genotypes I, II and III revealed internal groups that we have called lineages and sub-lineages. All amino acids that characterize a group (genotype, lineage, or sub-lineage) are located in the 47 variable sites of the E protein. Conclusion Our results provide information about the most frequent amino acid changes and diversity of the E protein of DENV-3.

Highlights • Minimalist two channel surface EMG system for hand gesture detection is demonstrated. • Support vector machine classification can detect five hand gestures with two sEMG channels. • Overall classification rate of over 90% is demonstrated. • A gesture is defined for locking/unlocking of the system which adds to the robustness. Abstract Integration of surface EMG sensors as an input source for Human Machine Interfaces (HMIs) is getting an increasing attention due to their application in wearable devices such as armbands. For a wearable device, comfort and lightness are important factors. Therefore, in this article we focus on a minimalistic approach, in which we try to classify four gestures with only 2 EMG channels installed on the flexor and extensor muscles of the forearm. We adopted a two-channel EMG system, together with a high dimensional feature-space and a support vector machine (SVM) as a classifier. In addition, tolerance of the system for rejection of unsolicited gestures during the body movement was evaluated, and the two methods were implemented to ensure this; one based on an SVM threshold and another one based on the addition of a locking gesture. The resulting system is able to recognize up to 5 gestures (hand closing, hand opening, wrist flexion, wrist extension and double wrist flexion), presenting a classification accuracy of between 95% and 100% for a trained user and robustness against different body movements, guaranteed with the locking feature. We showed that misclassification of other gestures as the unlocking never happened for expert users. [ABSTRACT FROM AUTHOR]

The evolution of outsourcing Information Technology (IT) Services has been accompanying the movement of technological innovations and the changes in IT governance. This development has motivated organizations to conduct decision-making integrating preferences from managers of different sectors in the Enterprise in order to improve the decision process. This paper presents a group decision model that can incorporate the preferences from different managers based on Promethee method and analysis of individual priorities with the aim of choosing an appropriate alternative for outsourcing IT service. The model is illustrated by a case study in an Enterprise in the Commercial Sector using the preferences from three managers (Support and IT Services Manager; Infrastructure Manager; and Development Systems Manager) demonstrating the benefits to formalize the integration among them to facilitate achieving an adequate alternative for outsourcing IT service. [ABSTRACT FROM AUTHOR]

White Storks (Ciconia ciconia L.) may cause severe outages in electric networks leading to poor power quality service. Furthermore, bird fatalities often occur as consequence of electrocution. Therefore, equipment damages, economical losses of industry and electric corporations and bird deaths persuaded the main electric distribution operator and the regulator to implement management programs of storks' activities in the vicinity of electric distribution substructure to minimize stork fatalities and energy outages. Stork management in electric distribution networks is implemented by using sounds, strobes, vibration and turbine devices. These systems are activated upon storks approaching the putative nesting sites. The storks are detected by ultrasonic sensor probes. Sound equipment was modified as specifically required to allow remote control and monitoring via Internet connection. Particularly effective were strong harassment sounds, e. g. guns, alarms, sirens, and dynamic powerful musical passages. Natural distress calls of herons and egrets were also effective. Ultrasonic frequencies, predator sounds (falcons, hawks) and general bird distress calls (gulls, pigeons, starlings) were of limited effects. To keep birds from adapting to routine patterns, the devices were activated only upon approaching detected by ultrasonic probes, and a random combination of 8 sound pieces played for 10 min. Novel vibration platforms proved effective in preventing nesting and roosting, but relatively difficult to install with the current prototype design. Specially designed powered turbines powered by a high torque motor effectively prevented storks from nesting, in spite of several attempts. [ABSTRACT FROM AUTHOR]