Alternative Stable States
Mostrando 1-12 de 19 artigos, teses e dissertações.
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1. O papel das macrófitas submersas sobre a qualidade da água, restauração e conservaçao de lagos rasos subtropicais : estudo de caso, a Lagoa Mangueira, RS
O objetivo desta Tese foi avaliar o papel da macrófitas submersas em relação à qualidade da água, interações com o fitoplâncton e ciclagem biogeoquímica na Lagoa Mangueira, um grande lago raso subtropical, no sul do Brasil. Para alcançar estes objetivos, este trabalho conta com uma série de abordagens, como: levantamentos de campo, etapas experime
Publicado em: 2010
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2. EVALUATION OF RADIOLABELING OF ANNEXIN A5 WITH TECHNETIUM-99m: INFLUENCE OF THE LABELING METHODS ON PHYSICO-CHEMICAL AND BIOLOGICAL PROPERTIES OF THE COMPOUNDS / Avaliação da radiomarcação da anexina A5 com Tecnécio-99m: influência do método de marcação nas propriedades físicos-químicas e biológicas do composto
Annexin A5 (ANXA5) is an intracellular human protein of 36 kDa with high affinity for membrane-bound phosphatidylserine that is selectively exposed on the surface of cells undergoing apoptosis. Apoptosis is important in normal physiology and innumerous pathologic states. Clinical applications for ANXA5 imaging are being developed in oncology, organ transplan
Publicado em: 2009
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3. Ku-deficient yeast strains exhibit alternative states of silencing competence
In Saccharomyces cerevisiae, efficient silencer function requires telomere proximity, i.e. compartments of the nucleoplasm enriched in silencing factors. Accordingly, silencers located far from telomeres function inefficiently. We show here that cells lacking yKu balance between two mitotically stable states of silencing competence. In one, a partial delocal
Oxford University Press.
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4. The role of noise in a predator–prey model with Allee effect
The existence and implications of alternative stable states in ecological systems have been investigated extensively within deterministic models. However, it is known that natural systems are undeniably subject to random fluctuations, arising from either environmental variability or internal effects. Thus, in this paper, we study the role of noise on the pat
Springer Netherlands.
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5. Cytochrome oxidase: an alternative model.
Oxidative titration of reduced cytochrome oxidase (cytochrome c oxidase; ferrocytochrome c:oxygen oxidoreductase, EC 1.9.3.1) in the presence of carbon monoxide and sulfide, at potentials greater than +500 mV (vs. the neutral hydrogen electrode), have failed to produce new copper signals in the electron paramagnetic resonance spectrum of this enzyme. This ob
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6. Theory of Muscular Contraction Extended to Groups of Actin Sites
It was shown in an earlier paper how to connect, in principle, the biochemical states of a cross-bridge with the mechanics of muscular contraction, by the methods of statistical mechanics. The treatment applies to cross-bridges that are able to interact with only one actin site at a time. The present paper shows that it is a straightforward matter to extend
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7. α/γ Transitions in the B-DNA backbone
In the crystal structures of protein complexes with B-DNA, α and γ DNA backbone torsion angles often exhibit non-canonical values. It is not known if these alternative backbone conformations are easily accessible in solution and can contribute to the specific recognition of DNA by proteins. We have analysed the coupled transition of the α and γ torsion a
Oxford University Press.
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8. Impact of Migration and Fitness on the Stability of Lethal T-Haplotype Polymorphism in Mus Musculus: A Computer Study
The t-haplotype is a chromosomal region in Mus musculus characterized by meiotic drive such that heterozygous males transmit t-bearing chromosomes to roughly 90% of their offspring. Most naturally occurring t-haplotypes express a recessive embryonic lethality, preventing fixation of the t-haplotype. Surprisingly, the t-haplotype occurs in nature as a persist
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9. Structural specificity conferred by a group I RNA peripheral element
Like proteins, structured RNAs must specify a native conformation that is more stable than all other possible conformations. Local structure is much more stable for RNA than for protein, so it is likely that the principal challenge for RNA is to stabilize the native structure relative to misfolded and partially folded intermediates rather than unfolded struc
National Academy of Sciences.
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10. Absolute quantification of proteins and phosphoproteins from cell lysates by tandem MS
A need exists for technologies that permit the direct quantification of differences in protein and posttranslationally modified protein expression levels. Here we present a strategy for the absolute quantification (termed AQUA) of proteins and their modification states. Peptides are synthesized with incorporated stable isotopes as ideal internal standard
National Academy of Sciences.
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11. Conservation of sigma–core RNA polymerase proximity relationships between the enhancer-independent and enhancer-dependent sigma classes
Two distinct classes of RNA polymerase sigma factors (σ) exist in bacteria and are largely unrelated in primary amino acid sequence and their modes of transcription activation. Using tethered iron chelate (Fe-BABE) derivatives of the enhancer-dependent σ54, we mapped several sites of proximity to the β and β′ subunits of the core RNA polymerase. Remar
Oxford University Press.
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12. Conformational model of the Holliday junction transition deduced from molecular dynamics simulations
Homologous recombination plays a key role in the restart of stalled replication forks and in the generation of genetic diversity. During this process, two homologous DNA molecules undergo strand exchange to form a four-way DNA (Holliday) junction. In the presence of metal ions, the Holliday junction folds into the stacked-X structure that has two alternative
Oxford University Press.