Theoretical pathways towards experimental quantum simulators

Recent progress in quantum optics and quantum information has brought the long-standing dreams of quantum simulators and even quantum computers (almost) within reach. Here, we review some current theoretical pathways supporting experimental progress towards quantum simulators. In this, we focus mainly on topological aspects and numerical studies of quantum computation. © Sociedad Española de Óptica.This work was funding by the Spanish MEC projects TOQATA (FIS2008-00784), QOIT (Consolider Ingenio 2010), ACUTE, ERC Advanced Grant QUAGATUA, EU STREP NAMEQUAM, partly (E. Sz.) by the Hungarian Research Fund (OTKA) under Grant No. 68340, the Barcelona Supercomputing Center - Centro Nacional de Supercomputación (FI2008-3-0029, FI2009-1-0019) (A.N.), and Alexander von Humboldt Foundation (M.L.).Peer Reviewe

A peptide derived from a polyreactive monoclonal anti-DNA natural antibody can modulate lupus development in (NZB×NZW)F1 mice

In lupus-prone (NZB×NZW)F1 (B/W) mice, elevated levels of polyreactive autoantibodies bearing the D23 idiotype (Id), characteristic of natural antibodies, were detected before and after the appearance of pathological anti-DNA antibodies. While these D23 Id+ antibodies were able to regulate anti-DNA antibodies in the early stage of the disease, we found that during disease evolution they had lost their normal ability to regulate anti-DNA antibodies and furthermore could participate in the lupus-like syndrome. To explore further the role of the D23 Id+ antibodies, we injected young B/W mice with a peptide corresponding to the VH CDR3 region of the D23 monoclonal natural antibody (mNAb). High levels of monospecific antipeptide, as well as polyreactive antibodies, were induced. Among them, the most markedly enhanced antibody population was DNA-reactive immunoglobulin G1 (IgG1). Compared with controls, these immunized mice had a delayed 50% survival rate and proteinuria developed later. Furthermore, IgG1 able to react with IgG2a anti-DNA monoclonal antibodies derived from B/W mice were also produced after peptide immunization. Thus, a peptide corresponding to the CDR3 of the D23 mNAb antibody might play a role in the regulation of murine lupus

Structural and morphogenical characteristics of black oats and Italian ryegrass on pasture submitted to two grazing intensities Características estruturais e morfogênicas de aveia-preta e azevém-anual em pastagem submetida a duas intensidades de pastejo

Morphogenical and structural characteristics of black oats (Avena strigosa Schreb.) and Italian ryegrass (Lolium multiflorum Lam.) on pastures managed under two grazing intensities were quantified by using marked tiller technique. The expected intensities of disappearance of forage mass initial value were 35% (low) and 65% (high). Experimental animals were sheep and interval among grazing was determined through 300 degree-day thermal sum. The experimental design was completely randomized with two grazing intensities and two replicates. Leaf blades of oats and ryegrass were removed at an average proportion of 57.5% of their initial length for both grazing intensities. Among the morphogenical characteristics of oats, only elongation rate of defoliate leaf differed between grazing intensities, with values of 0.059 and 0.081 cm/degree-day for low and high intensities, respectively. Grazing intensities did not alter structural characteristics of oats mixed with ryegrass and red clover. High grazing intensity enables maintenance of a higher number of ryegrass expanding leaves (1.7 leaves/tiller), thus it is suggested for management of pastures with oats mixed with Italian ryegrass and red-clover on intermittent grazing.<br>As características morfogênicas e estruturais de aveia-preta (Avena strigosa Schreb.) e azevém (Lolium multiflorum Lam.), em pastagem manejada sob duas intensidades de pastejo, foram quantificadas por meio da técnica de perfilhos marcados. As intensidades pretendidas de desaparecimento do valor da massa de forragem inicial foram 35% (baixa) e 65% (alta). Os animais experimentais foram ovinos e o intervalo entre pastejos foi determinado pela soma térmica de 300 graus-dia. O delineamento experimental foi inteiramente casualizado com duas intensidades de pastejo e duas repetições. As lâminas foliares de aveia e azevém foram removidas na proporção média de 57,5% do seu comprimento inicial em ambas as intensidades de pastejo. Entre as características morfogênicas da aveia, apenas a taxa de elongação de lâmina desfolhada diferiu entre as intensidades de pastejo, com valores de 0,059 e 0,081 cm/graus-dia para as intensidades alta e baixa, respectivamente. As intensidades de pastejo não provocaram alterações nas características estruturais da aveia em consorciação com azevém e trevo-vermelho. A intensidade de pastejo alta possibilita a manutenção de maior número de folhas em expansão de azevém (1,7 folhas/perfilho), portanto é recomendável para o manejo de pastagens da aveia em consórcio com azevém e trevo-vermelho sob pastejo intermitente