Controlling observables in normal, hybrid and Josephson junctions

The theory of time-dependent quantum transport addresses the question: How do electrons flow through a junction under the influence of an external perturbation as time goes by? In this article, we invert this question and search for a time-dependent bias such that the system behaves in a desired way. Our system of choice consists of quantum dots coupled to normal or superconducting leads. We present results for junctions with normal leads where the current, the density or a molecular vibration is optimised to follow a given target pattern. For junctions with two superconducting leads, where the Josephson effect triggers the current to oscillate, we investigate what happens if the frequency of the Josephson oscillation comes close to the frequency of the molecular vibration. Furthermore we show how to suppress the Josephson oscillations by suitably tailoring the bias. In a second example involving superconductivity, we consider a Y-shaped junction with two quantum dots coupled to one superconducting and two normal leads. This device is used as a Cooper pair splitter to create entangled electrons on the two quantum dots. We maximise the splitting efficiency with the help of an optimised bias

Structural basis for Z-DNA binding and stabilization by the zebrafish Z-DNA dependent protein kinase PKZ

The RNA-dependent protein kinase PKR plays a central role in the antiviral defense of vertebrates by shutting down protein translation upon detection of viral dsRNA in the cytoplasm. In some teleost fish, PKZ, a homolog of PKR, performs the same function, but surprisingly, instead of dsRNA binding domains, it harbors two Z-DNA/Z-RNA-binding domains belonging to the Zalpha domain family. Zalpha domains have also been found in other proteins, which have key roles in the regulation of interferon responses such as ADAR1 and DNA-dependent activator of IFN-regulatory factors (DAI) and in viral proteins involved in immune response evasion such as the poxviral E3L and the Cyprinid Herpesvirus 3 ORF112. The underlying mechanism of nucleic acids binding and stabilization by Zalpha domains is still unclear. Here, we present two crystal structures of the zebrafish PKZ Zalpha domain (DrZalpha(PKZ)) in alternatively organized complexes with a (CG)6 DNA oligonucleotide at 2 and 1.8 Å resolution. These structures reveal novel aspects of the Zalpha interaction with DNA, and they give insights on the arrangement of multiple Zalpha domains on DNA helices longer than the minimal binding site.FCT fellowship: (SFRH/BPD/71629/2010), ESRF BAG program, Instituto Gulbenkian de Ciência

Recreation carrying capacity estimations to support beach management at Praia de Faro, Portugal

The purpose of this research paper is to outline the theory and practice of tourism carrying capacity assessment and its relevance as a management tool for coastal management. Based on the Tourism Carrying Capacity Assessment for Protected Areas Framework and the Image Capture Technique associated with the PAOT (people at one time) approach, this paper explores Praia de Faro as the study area and attempts to assess the optimum number of people that should be allowed without jeopardizing the surrounding ecological, social and cultural environments. Results showed that the physico-ecological carrying capacity should be between 1385 and 2628 visitors/day with maximum impact acceptability curves being 305 and 608 tourists (for local people and tourists respectively). Although there was a significant difference between the physico-ecological and socio-cultural carrying capacity, this study suggests that the physico-ecological carrying may be applied for ecosystem management, whilst the socio-cultural carrying capacity may be addressed when management objectives are tourists and beach users

Cirugía funcionalizadora en la distrofia muscular progresiva (Enfermedad de Duchenne)

Presentamos una serie de 55 pacientes afectados de Distrofia Muscular Progresiva (Enfermedad de Duchenne) de los cuales 22 fueron operados de los miembros inferiores con tecnoplastias de Aquiles principalmente, biopedestados en el término de 24 hs. y equipados ortodésicamente en la primera semana y que por término medio prolongaron su independencia de marcha por 20 meses. El criterio utilizado, mejoró notablemente la calidad de vida de estos niños postergando la aparición de complicaciones secundarias cardiorespiratorias y escolióticas. Ante la realidad de una carencia actual de medidas terapéuticas efectivas todo criterio funcionalizador en el tiempo, justifica a nuestro entender la acción del equipo neuro ortopédico aún en patologías de fatal pronóstico como la presente.A series of 55 patients with Duchenne Progressive Muscular Dystrofy is reviewed. A total of 22 cases were operated on by Aquiles tenoplasty. These patients were encouraged to get standing position 24 hours after operation. Within the first week after operation patients could walk with ortesis. Mean follow-up was 20 mounths. The therapeutic protocol used has notably improved Ufe quality of these children, postponius the presence of cardiorrespiratory and escoliotic secondary complications

Simulação computacional da flutuação populacional do bicho-mineiro do cafeeiro em condições de campo para o Município de São Sebastião do Paraíso-MG.

Foram realizadas simulações da flutuação populacional de lagartas do bicho-mineiro do cafeeiro, Leucoptera coffeella (Guérin-Mèneville, 1842) (Lepidoptera: Lyonetiidae), utilizando-se dados de temperatura e precipitação pluvial relativos ao município de São Sebastião do Paraíso-MG no período de 1989 a 1993. Os resultados da simulação foram comparados com aqueles obtidos em pesquisa de campo realizado por Reis e Souza (1996), sendo verificado que para a maioria dos anos o modelo foi capaz de reproduzir os picos populacionais do inseto-praga

A functional of the one-body-reduced density matrix derived from the homogeneous electron gas: Performance for finite systems

An approximation for the exchange-correlation energy of reduced-density-matrix-functional theory was recently derived from a study of the homogeneous electron gas (N.N. Lathiotakis, N. Helbig, E.K.U. Gross, Phys. Rev. B 75, 195120 (2007)). In the present work, we show how this approximation can be extended appropriately to finite systems, where the Wigner Seitz radius r_s, the parameter characterizing the constant density of the electron gas, needs to be replaced. We apply the functional to a variety of molecules at their equilibrium geometry, and also discuss its performance at the dissociation limit. We demonstrate that, although originally derived from the uniform gas, the approximation performs remarkably well for finite systems.Comment: 5 pages, 2 figuere

Improving SeNA-CNN by Automating Task Recognition

Catastrophic forgetting arises when a neural network is not capable of preserving the past learned task when learning a new task. There are already some methods proposed to mitigate this problem in arti cial neural networks. In this paper we propose to improve upon our previous state-of-the-art method, SeNA-CNN, such as to enable the automatic recognition in test time of the task to be solved and we experimentally show that it has excellent results. The experiments show the learning of up to 4 di erent tasks with a single network, without forgetting how to solve previous learned tasks.info:eu-repo/semantics/publishedVersio

Potencial de predação de três espécies de fitoseídeos sobre Oligonychus ilicis (McGREGOR, 1917)(Acari: Tetranychidae).

O ácaro-vermelho, Oligonychus ilicis (McGregor, 1917), é um dos principais ácaros fitófagos do cafeeiro (Coffea spp.), sendo responsável por causar o bronzeamento nas folhas e como conseqüência do ataque há redução da capacidade fotossintetizadora das mesmas. Ácaros pertencentes à família Phytoseiidae são considerados os mais importantes e estudados dentre os predadores de ácaros-praga. O objetivo deste trabalho foi avaliar o potencial de predação de Iphiseiodes zuluagai Denmark & Muma, 1972; Euseius citrifolius Denmark & Muma, 1970 e Amblyseius herbicolus (Chant, 1959) (Acari: Phytoseiidae) sobre as diversas fases do desenvolvimento de O. ilicis. O delineamento experimental foi o inteiramente casualizado com cinco tratamentos: testemunha sem predador, larva, ninfa e adulto: macho (exceto para A. herbicolus) e fêmea do predador, com dez repetições. Cada repetição constou de uma arena (disco de folha de cafeeiro, Coffea arabia L.), onde foram colocados 25 ácaros O. ilicis e um ácaro predador, em experimentos independentes. Após 24 horas, observou-se que a fase de fêmea adulta dos predadores foi a mais eficiente na predação, seguida pela fase de ninfa, macho e larva. Adultos de O. ilicis não foram preferidos para predação por todas as fases do desenvolvimento dos ácaros predadores e as larvas foram as preferidas