Feasibility study for a scanning celestial attitude determination system SCADS on the IMP spacecraft Final report

System design analysis to establish feasibility of using electro-optical celestial scanning sensor on IMP spacecraft for determination of spacecraft attitude by star measurement

Feasibility study for a Scanning Celestial Attitude Determination System /SCADS/ for three axis attitude determination at a Command and Data Acquisition /CDA/ station Final report

Scanning Celestial Attitude Determination System /SCADS/ for three axis attitude determination at Command and Data Acquisition /CDA/ statio

Produção de antissoro policlonal utilizando a proteína capsidial recombinante do Rupestris stem pitting-associated virus.

O Rupestris stem pitting-associated virus (RSPaV) é o agente causal das caneluras do lenho da videira. Este trabalho teve como objetivo produzir antissoro policlonal a partir da proteína capsidial (CP) recombinante do RSPaV e avaliar a sua especificidade e sensibilidade. O gene da CP do RSPaV, com 780pb, foi previamente caracterizado. Esse gene foi subclonado no sítio de restrição EcoRI, no vetor de expressão pRSET-B e o plasmídeo recombinante foi utilizado para induzir a expressão da CP em Escherichia coli. A CP, ligada a uma cauda de seis histidinas, foi purificada por meio de cromatografia de afinidade em coluna de Ni-NTA a partir do extrato de proteínas totais extraídas de E. coli. A identidade da proteína purificada foi confirmada em SDS-PAGE e Western blot, utilizando-se anticorpos comerciais contra a cauda de seis histidinas. A CP recombinante expressada in vitro apresentou massa molecular de cerca de 31kDa. A proteína purificada foi quantificada e 2,55mg foram utilizados para a imunização de um coelho. O antissoro policlonal obtido reagiu com diferentes isolados deste vírus, extraídos de videiras em ELISA indireto.Nota técnica

Simultaneous detection of Brazilian isolates of grapevine viruses by TaqMan real-time RT-PCR.

The aim of this work was to evaluate the efficiency of real-time RT-PCR for detection of different isolates of ten important virus species that infect grapevines in Brazil: Grapevine leafroll-associated virus (GLRaV-1, -2, -3 and -5), Grapevine virus A (GVA), Grapevine virus B (GVB), Grapevine virus D (GVD), Grapevine rupestris stem pitting-associated virus (GRSPaV), Grapevine fleck virus (GFkV) and Grapevine fanleaf virus (GFLV). The reactions consisted of individual (simplex) and simultaneous (duplex) virus detections. Thirty six grapevine accessions, regenerated after thermotherapy and tissue culture treatments, have been analysed. All the above-mentioned viruses were sensitively detected in simplex reactions in samples infected with different virus isolates. Specifically to GLRaV-1 it was necessary to mix reagents refered by different sources to achieve the amplification. GVA, GRSPaV, GLRaV-2 and GLRaV-3 combined with GVB, GFLV, GFkV, GVD and GLRaV-5 were accurately detected in duplex trials. It was shown, that real-time RT-PCR (TaqMan) is able to efficiently detect different local virus species and isolates.Comunicação científica

Asymmetry to symmetry transition of Fano line-shape: Analytical derivation

An analytical derivation of Fano line-shape asymmetry ratio has been presented here for a general case. It is shown that Fano line-shape becomes less asymmetric as \q is increased and finally becomes completely symmetric in the limiting condition of q equal to infinity. Asymmetry ratios of Fano line-shapes have been calculated and are found to be in good consonance with the reported expressions for asymmetry ratio as a function of Fano parameter. Application of this derivation is also mentioned for explanation of asymmetry to symmetry transition of Fano line-shape in quantum confined silicon nanostructures.Comment: 3 figures, Latex files, Theoretica

Detecção por RT-PCR em Tempo Real e caracterização molecular do Grapevine virus D e Grapevine leafroll-associated virus 5 em videira.

O objetivo deste trabalho foi verificar a ocorrência destes dois vírus em videiras por meio de RT-PCR em Tempo Real, além de caracterizar molecularmente três dos isolados obtidos.Resumo

Singularities of nn-fold integrals of the Ising class and the theory of elliptic curves

We introduce some multiple integrals that are expected to have the same singularities as the singularities of the $n$-particle contributions $\chi^{(n)}$ to the susceptibility of the square lattice Ising model. We find the Fuchsian linear differential equation satisfied by these multiple integrals for $n=1, 2, 3, 4$ and only modulo some primes for $n=5$ and $6$, thus providing a large set of (possible) new singularities of the $\chi^{(n)}$. We discuss the singularity structure for these multiple integrals by solving the Landau conditions. We find that the singularities of the associated ODEs identify (up to $n= 6$) with the leading pinch Landau singularities. The second remarkable obtained feature is that the singularities of the ODEs associated with the multiple integrals reduce to the singularities of the ODEs associated with a {\em finite number of one dimensional integrals}. Among the singularities found, we underline the fact that the quadratic polynomial condition $1+3 w +4 w^2 = 0$, that occurs in the linear differential equation of $\chi^{(3)}$, actually corresponds to a remarkable property of selected elliptic curves, namely the occurrence of complex multiplication. The interpretation of complex multiplication for elliptic curves as complex fixed points of the selected generators of the renormalization group, namely isogenies of elliptic curves, is sketched. Most of the other singularities occurring in our multiple integrals are not related to complex multiplication situations, suggesting an interpretation in terms of (motivic) mathematical structures beyond the theory of elliptic curves.Comment: 39 pages, 7 figure

Biological and molecular characterization of two Brazilian isolates of Apple stem grooving virus.

Apple stem grooving virus (ASGV, genus Capillovirus) is disseminated worldwide, usually causing a latent infection in most commercial apple cultivars. However, infected scions grafted onto sensitive material display reduction of yield, loss of fruit quality and tree decline. In Brazil ASGV is associated with severe phloem necrosis, xylem pitting and decline of apple trees on Maruba-kaido (Malus prunifolia cv. Ringo) rootstocks usually in a complex with other latent viruses. Two Brazilian ASGV isolates from a mixed infection causing differing reactions on apple cv. Fuji on Maruba-kaido rootstocks, i.e., normal growth vs. tree decline, have been completely sequenced. The differing intensity of symptoms they co-induced on several woody indicator species/cultivars are indicative of biological differences between the two inocula. Their nucleotide sequences are 92.2% identical and display between 79.2% and 97.1% identity with other ASGV isolates available in GenBank. The two isolates (M219-3 and M220) shared 92.3% deduced amino acid (daa) sequence identity for ORF1, 95.3% for ORF2 and 93.3% for the CP gene. A high degree of daa identity, 95.8% and 96.6%, was ob- served between the CPs of M219 ? 3 and M220, respectively, with the Brazilian isolate UV01. Potential recombination events and phy logenetic relationships to major parents were investigated in isolates M219 ? 3and M220. Keywords ASGV . Apple virus . Phylogenetic analysis . Recombinatio