Brownian Motions
Mostrando 1-12 de 13 artigos, teses e dissertações.
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1. Damping of the Woodwind Instrument Reed Material Arundo donax L
The viscoelastic properties (E', G', tanΦ, δ) of Arundo donax (AD) and a polypropylene-beech fiber composite (PPC) were measured from RT to 580K for various frequencies and strains. E' of AD varies between 5250-6250MPa depending on ageing at RT while E'(RT)=2250MPa of PPC is signifcantly lower. E' of the AD is higher than E' of PPC in the whole investigate
Mat. Res.. Publicado em: 04/06/2018
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2. Calculo estotastico em variedades Finsler
Nesta dissertação fizemos um estudo da teoria de difusão em variedades Finsler, onde abor-damos o transporte paralelo estocástico, desenvolvimento estocástico de Cartan e Movimento Browniano. O objetivo principal é obter uma descrição mais geométrica dos objetos citados acima ainda que por enquanto em coordenadas locais e assim termos um paralelo en
Publicado em: 2005
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3. Stochastic Molecular Dynamics of colloidal particles
Colloidal particles move in the carrier liquid under the action of several forces and torques. When the particles carry a dipole moment, electric or magnetic, as in ferrofluids, the rotational and translational motions are coupled because the field on a particle depends on the spatial and directional distribution of the others and the force and torque on it
Brazilian Journal of Physics. Publicado em: 2004-06
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4. Cell motility driven by actin polymerization.
Certain kinds of cellular movements are apparently driven by actin polymerization. Examples include the lamellipodia of spreading and migrating embryonic cells, and the bacterium Listeria monocytogenes, that propels itself through its host's cytoplasm by constructing behind it a polymerized tail of cross-linked actin filaments. Peskin et al. (1993) formulate
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5. Cellular motions and thermal fluctuations: the Brownian ratchet.
We present here a model for how chemical reactions generate protrusive forces by rectifying Brownian motion. This sort of energy transduction drives a number of intracellular processes, including filopodial protrusion, propulsion of the bacterium Listeria, and protein translocation.
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6. The Brownian Web
Arratia, [Arratia, R. (1979) Ph.D. thesis (University of Wisconsin, Madison) and unpublished work] and later Toth and Werner [Toth, B. & Werner, W. (1998) Probab. Theory Relat. Fields111, 375–452] constructed random processes that formally correspond to coalescing one-dimensional Brownian motions starting from every space-time point. We extend their work b
National Academy of Sciences.
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7. Brownian dynamics simulations of supercoiled DNA with bent sequences.
The recently presented Brownian dynamics model for superhelical DNA is extended to include local curvature of the DNA helix axis. Here we analyze the effect of a permanent bend on the structure and dynamics of an 1870-bp superhelix with delta Lk = -10. Furthermore, we define quantitative expressions for computing structural parameters such as loop positions,
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8. Constrained diffusion or immobile fraction on cell surfaces: a new interpretation.
Protein lateral mobility in cell membranes is generally measured using fluorescence photobleaching recovery (FPR). Since the development of this technique, the data have been interpreted by assuming free Brownian diffusion of cell surface receptors in two dimensions, an interpretation that requires that a subset of the diffusing species remains immobile. The
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9. Brownian dynamics simulations of probe and self-diffusion in concentrated protein and DNA solutions.
We have developed a Brownian dynamics algorithm for simulating probe and self-diffusion in concentrated solutions of DNA and protein. In these simulations, proteins are represented as spheres with radii given by their hydrodynamic radii, while DNA is modeled as a wormlike chain of hydrodynamically equivalent spherical frictional elements. The molecular inter
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10. Salt effects on the structure and internal dynamics of superhelical DNAs studied by light scattering and Brownian dynamics.
Using laser light scattering, we have measured the static and dynamic structure factor of two different superhelical DNAs, p1868 (1868 bp) and simian virus 40 (SV40) (5243 bp), in dilute aqueous solution at salt concentrations between 1 mM and 3 M NaCl. For both DNA molecules, Brownian dynamics (BD) simulations were also performed, using a previously describ
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11. Dynamics of heme iron in crystals of metmyoglobin and deoxymyoglobin.
The 57Fe gamma-ray resonance absorption spectra have been measured in crystals of metmyoglobin and deoxymyoglobin over a wide range of temperatures. Above a critical temperature common to both proteins (220 K), the dynamics of heme iron display a dramatic change, in that two kinds of thermal fluctuations come into play--a fast fluctuation associated with a s
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12. Dynamic strength of molecular adhesion bonds.
In biology, molecular linkages at, within, and beneath cell interfaces arise mainly from weak noncovalent interactions. These bonds will fail under any level of pulling force if held for sufficient time. Thus, when tested with ultrasensitive force probes, we expect cohesive material strength and strength of adhesion at interfaces to be time- and loading rate