165 research outputs found
Single Heavy Flavour Baryons using Coulomb plus Power law interquark Potential
Properties of single heavy flavor baryons in a non relativistic potential
model with colour coulomb plus power law confinement potential have been
studied. The ground state masses of single heavy baryons and the mass
difference between the ( and ) states are
computed using a spin dependent two body potential. Using the spin-flavour
structure of the constituting quarks and by defining an effective confined mass
of the constituent quarks within the baryons, the magnetic moments are
computed. The masses and magnetic moments of the single heavy baryons are found
to be in accordance with the existing experimental values and with other
theoretical predictions. It is found that an additional attractive interaction
of the order of -200 Me is required for the antisymmetric states of
(Q. It is also found that the spin hyperfine
interaction parameters play decisive role in hadron spectroscopy.Comment: 16 Pages, 3 Figures, Paper submitted in EPJ
Entropy and Barrier-Hopping Determine Conformational Viscoelasticity in Single Biomolecules
Biological macromolecules have complex and non-trivial energy landscapes,
endowing them a unique conformational adaptability and diversity in function.
Hence, understanding the processes of elasticity and dissipation at the
nanoscale is important to molecular biology and also emerging fields such as
nanotechnology. Here we analyse single molecule fluctuations in an atomic force
microscope (AFM) experiment using a generic model of biopolymer viscoelasticity
that importantly includes sources of local `internal' conformational
dissipation. Comparing two biopolymers, dextran and cellulose, polysaccharides
with and without the well-known `chair-to-boat' transition, reveals a signature
of this simple conformational change as minima in both the elasticity and
internal friction around a characteristic force. A calculation of two-state
populations dynamics offers a simple explanation in terms of an elasticity
driven by the entropy, and friction by barrier-controlled hopping, of
populations on a landscape. The microscopic model, allows quantitative mapping
of features of the energy landscape, revealing unexpectedly slow dynamics,
suggestive of an underlying roughness to the free energy.Comment: 25 pages, 7 figures, naturemag.bst, modified nature.cls
(naturemodified.cls
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