Universal and deterministic manipulation of the quantum state of harmonic oscillators: a route to unitary gates for Fock State qubits

We present a simple quantum circuit that allows for the universal and deterministic manipulation of the quantum state of confined harmonic oscillators. The scheme is based on the selective interactions of the referred oscillator with an auxiliary three-level system and a classical external driving source, and enables any unitary operations on Fock states, two-by-two. One circuit is equivalent to a single qubit unitary logical gate on Fock states qubits. Sequences of similar protocols allow for complete, deterministic and state-independent manipulation of the harmonic oscillator quantum state.Comment: 4 pages, 4 figure

Abrupt Changes in the Dynamics of Quantum Disentanglement

Entanglement evolution in high dimensional bipartite systems under dissipation is studied. Discontinuities for the time derivative of the lower bound of entanglement of formation is found depending on the initial conditions for entangled states. This abrupt changes along the evolution appears as precursors of entanglement sudden death.Comment: 4 pages and 6 figures, submitted for publicatio

Feasibility of approximating spatial and local entanglement in long-range interacting systems using the extended Hubbard model

We investigate the extended Hubbard model as an approximation to the local and spatial entanglement of a one-dimensional chain of nanostructures where the particles interact via a long range interaction represented by a `soft' Coulomb potential. In the process we design a protocol to calculate the particle-particle spatial entanglement for the Hubbard model and show that, in striking contrast with the loss of spatial degrees of freedom, the predictions are reasonably accurate. We also compare results for the local entanglement with previous results found using a contact interaction (PRA, 81 (2010) 052321) and show that while the extended Hubbard model recovers a better agreement with the entanglement of a long-range interacting system, there remain realistic parameter regions where it fails to predict the quantitative and qualitative behaviour of the entanglement in the nanostructure system.Comment: 6 pages, 5 figures and 1 table; added results with correlated hopping term; accepted by EP

Immune Reconstitution Inflammatory Syndrome: Opening Pandora's Box

One of the purposes of antiretroviral therapy (ART) is to restore the immune system. However, it can sometimes lead to an aberrant inflammatory response and paradoxical clinical worsening known as the immune reconstitution inflammatory syndrome (IRIS). We describe a 23-year-old male, HIV1 infected with a rapid progression phenotype, who started ART with TCD4+ of 53 cells/mm(3) (3,3%) and HIV RNA = 890000 copies/mL (6 log). Four weeks later he was admitted to the intensive care unit with severe sepsis. The diagnostic pathway identified progressive multifocal leukoencephalopathy, digestive Kaposi sarcoma, and P. aeruginosa bacteraemia. Five weeks after starting ART, TCD4+ cell count was 259 cells/mm(3) (15%) and HIV RNA = 3500 copies/mL (4 log). He developed respiratory failure and progressed to septic shock and death. Those complications might justify the outcome but its autopsy opened Pandora's box: cerebral and cardiac toxoplasmosis was identified, as well as hemophagocytic syndrome, systemic candidiasis, and Mycobacterium avium complex infection. IRIS remains a concern and eventually a barrier to ART. Male gender, young age, low TCD4 cell count, and high viral load are risk factors. The high prevalence of subclinical opportunistic diseases highlights the need for new strategies to reduce IRIS incidence.info:eu-repo/semantics/publishedVersio

From Clinical Presentation to the Outcome: the Natural History of PML in a Portuguese Population of HIV Infected Patients

Background Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system, associated with immunosuppression states. As there are only some non-published documents concerning PML in HIV infected patients in Portugal, we pretend to characterize natural history of PML infection in a population of HIV patients. Methods We retrospectively reviewed, from 1992 to 2009, PML cases in a population of 724 HIV infected patients followed in our institution. Clinical, biological, imagery features and outcomes were characterized. Results Twenty-five (3.45%) patients were identified as having PML. The mean time between HIV and PML diagnosis was 20.4 months. PML was the presentation of HIV infection in 40% of the patients, and 92% had CD4 T cell count lower than 200/mm3. Paresis was the most common clinical presentation. No specific characteristics were found in cerebrospinal fluid and JCV DNA was positive in 3 of 7 patients. MRI revealed characteristic findings. Combined antiretroviral therapy was started or changed in 96% of the patients. Neurological condition got worse in 12 patients. From the 14 deaths, 5 were directly attributed to PML progression. Follow-up was lost in 8 patients. Conclusions PML was the presentation of HIV infection in more than 1/3 of patients, frequently associated with advanced immunocompromise. MRI sensitivity to PML is high, and JCV DNA determination in CSF was not revealed to be sensible. PML diagnosis should be taken into account in HIV patients presenting any neurological symptoms, and HIV infection should be suspected when radiological findings suggest PML lesions even in previously healthy individuals

Crescimento inicial de milho em solo adubado com diferentes compostos orgânicos.

Foram elaborados cinco compostos orgânicos com diferentes composições, todos a base de esterco caprino, bagaço de coco e capim elefante, enriquecidos com torta de mamona, fosfato natural de gafsa e sulfato de potássio, de modo que, a final, cada pilha tivesse concentrações diferenciadas de nutrientes. O experimento foi montado em vasos contendo solo e os compostos preparados, dispostos em delineamento experimental inteiramente casualisado,, com seis tratamentos, sendo uma testemunha, e quatro repetições. Aos 28 dias após o plantio foi efetuado o corte das plantas, avaliando-se o número de folhas, a altura das plantas, o diâmetro do colo e o peso de matéria seca. De um modo geral, os compostos promoveram maior crescimento das plantas de milho que a testemunha (sem composto) com destaque para o composto de número 22 (77% de bagaço de coco, 20% de esterco caprino e 3% de sulfato de potássio)

Estudo da FAPAR em regiões fitoecológicas brasileiras através de série temporal derivada do NDVI/AVHRR.

The objective of this work is to study the behavior of Brazilian vegetation throughout time series of Fraction of Photosynthetically Active Radiation (FAPAR) absorbed by a plant canopy derived from vegetation index of the A VHRR sensor; observing the variations of the types of vegetation, influences and relationships with the cIimate. The F AP AR dataset has spatial resolution of 0.1 °xO.1 o and temporal resolution of 10 days for the period 1982 to 1999. The data were investigated considering the seasonal and interannual variations for phytoecological regions of the country. The FAPAR results show: the largest values were observed in Evergreen Broadleaf Forests (Dense and Open) and Campinarana, the lesser amplitude of variation of FAPAR occur in Savanna and Savanna-Steppe, due to adaptation to environmental changes. Analyses of F AP AR demonstrate that ecosystems with ali strata and structured soil have higher values. Even though, the preliminary results confirm that exists evidences ofrelation between the behavior of the FAPAR and weather conditions. The ENSO events have influence on interannual variations of FAPAR, mainly in the North and Northeast. Furthermore, the discussion presents that the FAPAR has potential to be used as an indicator of the photosynthetic process and consequently in the monitoring ofprimary production