4,878 research outputs found
Transformação estável da linhagem celular BTI-Tn-5B1-4 utilizando o gene 25KFP do baculovirus AgMNPV.
bitstream/CENARGEN/29465/1/bp188.pd
Avaliação de tetraplóides de bananeira cultivados em área infestada por mal-do-Panamá: segundo ciclo.
O mal-do-Panamá uma das mais importantes doenças da bananeira, causada pelo fungo Fusarium oxysporum f.sp. cubense, provoca elevadas perdas na produção. Esse trabalho teve como objetivo, avaliar, no segundo ciclo, as características agronômicas e a reação ao Fusarium de genótipos de bananeira. Foram avaliadas nove cultivares usando a Maçã como testemunha (suscetível), em delineamento inteiramente casualizado, com 10 repetições de uma planta. Avaliaram-se oito características agronômicas e a incidência de Fusarium. Há uma ampla variação genética para todos os caracteres agronômicos avaliados. Os híbridos de Prata Anã são superiores em produção aos de Pacovan. Os genótipos Porp, P.Jussara, Fhia-01 e PA94-01 são resistentes ao mal-do-Panamá.pdf 218
Explicit kinetic heterogeneity: mechanistic models for interpretation of labeling data of heterogeneous cell populations
Estimation of division and death rates of lymphocytes in different conditions
is vital for quantitative understanding of the immune system. Deuterium, in the
form of deuterated glucose or heavy water, can be used to measure rates of
proliferation and death of lymphocytes in vivo. Inferring these rates from
labeling and delabeling curves has been subject to considerable debate with
different groups suggesting different mathematical models for that purpose. We
show that the three models that are most commonly used are in fact
mathematically identical and differ only in their interpretation of the
estimated parameters. By extending these previous models, we here propose a
more mechanistic approach for the analysis of data from deuterium labeling
experiments. We construct a model of "kinetic heterogeneity" in which the total
cell population consists of many sub-populations with different rates of cell
turnover. In this model, for a given distribution of the rates of turnover, the
predicted fraction of labeled DNA accumulated and lost can be calculated. Our
model reproduces several previously made experimental observations, such as a
negative correlation between the length of the labeling period and the rate at
which labeled DNA is lost after label cessation. We demonstrate the reliability
of the new explicit kinetic heterogeneity model by applying it to artificially
generated datasets, and illustrate its usefulness by fitting experimental data.
In contrast to previous models, the explicit kinetic heterogeneity model 1)
provides a mechanistic way of interpreting labeling data; 2) allows for a
non-exponential loss of labeled cells during delabeling, and 3) can be used to
describe data with variable labeling length
The genome sequence of Pseudoplusia includes single nucleopolyhedrovirus and an analysis of p26 gene evolution in the baculoviruses.
Background: Pseudoplusia includens single nucleopolyhedrovirus (PsinSNPV-IE) is a baculovirus recently identified in our laboratory, with high pathogenicity to the soybean looper, Chrysodeixis includens (Lepidoptera: Noctuidae) (Walker, 1858). In Brazil, the C. includens caterpillar is an emerging pest and has caused significant losses in soybean and cotton crops. The PsinSNPV genome was determined and the phylogeny of the p26 gene within the family Baculoviridae was investigated. Results: The complete genome of PsinSNPV was sequenced (Roche 454 GS FLX ? Titanium platform), annotated and compared with other Alphabaculoviruses, displaying a genome apparently different from other baculoviruses so far sequenced. The circular double-stranded DNA genome is 139,132 bp in length, with a GC content of 39.3 % and contains 141 open reading frames (ORFs). PsinSNPV possesses the 37 conserved baculovirus core genes, 102 genes found in other baculoviruses and 2 unique ORFs. Two baculovirus repeat ORFs (bro) homologs, bro-a (Psin33) and bro-b (Psin69), were identified and compared with Chrysodeixis chalcites nucleopolyhedrovirus (ChchNPV) and Trichoplusia ni single nucleopolyhedrovirus (TnSNPV) bro genes and showed high similarity, suggesting that these genes may be derived from an ancestor common to these viruses. The homologous repeats (hrs) are absent from the PsinSNPV genome, which is also the case in ChchNPV and TnSNPV. Two p26 gene homologs (p26a and p26b) were found in the PsinSNPV genome. P26 is thought to be required for optimal virion occlusion in the occlusion bodies (OBs), but its function is not well characterized. The P26 phylogenetic tree suggests that this gene was obtained from three independent acquisition events within the Baculoviridae family. The presence of a signal peptide only in the PsinSNPV p26a/ORF-20 homolog indicates distinct function between the two P26 proteins. Conclusions: PsinSNPV has a genomic sequence apparently different from other baculoviruses sequenced so far. The complete genome sequence of PsinSNPV will provide a valuable resource, contributing to studies on its molecular biology and functional genomics, and will promote the development of this virus as an effective bioinsecticide
Quantum correlations in a few-atom spin-1 Bose-Hubbard model
We study the thermal quantum correlations and entanglement in spin-1 Bose-Hubbard model with two and three particles. While we use negativity to calculate entanglement, more general non-classical correlations are quantified using a new measure based on a necessary and sufficient condition for zero-discord state. We demonstrate that the energy level crossings in the ground state of the system are signalled by both the behavior of thermal quantum correlations and entanglement
Algebraic expansions for curvature coupled scalar field models
A late time asymptotic perturbative analysis of curvature coupled complex
scalar field models with accelerated cosmological expansion is carried out on
the level of formal power series expansions. For this, algebraic analogues of
the Einstein scalar field equations in Gaussian coordinates for space-time
dimensions greater than two are postulated and formal solutions are constructed
inductively and shown to be unique. The results obtained this way are found to
be consistent with already known facts on the asymptotics of such models. In
addition, the algebraic expansions are used to provide a prospect of the large
time behaviour that might be expected of the considered models.Comment: 16 pages, no figures; v2: typos corrected, references adde
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