9,398 research outputs found
Sensitivity of 8B breakup cross section to projectile structure in CDCC calculations
Given the Astrophysical interest of BeB, there have been
several experiments applying the Coulomb dissociation method for extracting the
capture rate. Measurements at Michigan State are dominated by
contributions but have a small component. On the other hand, a lower
energy measurement at Notre Dame has a much stronger contribution. The
expectation was that the two measurements would tie down the and thus
allow for an accurate extraction of the relevant for the capture process.
The aim of this brief report is to show that the factor in breakup
reactions does not translate into a scaling of the contribution in the
corresponding capture reaction. We show that changes to the B single
particle parameters, which are directly related to the component in the
capture reaction, do not effect the corresponding breakup reactions, using the
present reaction theory.Comment: 4 pages, 6 figures, revtex
A Fluid Model for the Interaction of the Solar Wind and the Geomagnetic Field
Solar wind and geomagnetic field interaction in terms of continuum theory of fluid flo
Local Operations and Completely Positive Maps in Algebraic Quantum Field Theory
Einstein introduced the locality principle which states that all physical
effect in some finite space-time region does not influence its space-like
separated finite region. Recently, in algebraic quantum field theory, R\'{e}dei
captured the idea of the locality principle by the notion of operational
separability. The operation in operational separability is performed in some
finite space-time region, and leaves unchanged the state in its space-like
separated finite space-time region. This operation is defined with a completely
positive map. In the present paper, we justify using a completely positive map
as a local operation in algebraic quantum field theory, and show that this
local operation can be approximately written with Kraus operators under the
funnel property
Nonlocal hydrodynamic influence on the dynamic contact angle: Slip models versus experiment
Experiments reported by Blake et al. [Phys. Fluids. 11, 1995 (1999)] suggest that the dynamic contact angle formed between the free surface of a liquid and a moving solid boundary at a fixed contact-line speed depends on the flow field/geometry near the moving contact line. The present paper examines quantitatively whether or not it is possible to attribute this effect to bending of the free surface due to hydrodynamic stresses acting upon it and hence interpret the results in terms of the so-called ``apparent'' contact angle. It is shown that this is not the case. Numerical analysis of the problem demonstrates that, at the spatial
resolution reported in the experiments, the variations of the ``apparent'' contact angle (defined in two different ways) caused by variations in the flow field, at a fixed contact-line speed, are too small to account for the observed effect. The results clearly indicate that the actual (macroscopic) dynamic contact angle, i.e.\ the one used in fluid mechanics as a boundary condition for the equation determining the free surface shape, must be regarded as dependent not only on the contact-line speed but also on the flow field/geometry in the vicinity of the moving contact line
Unravelling the Enzymatic Degradation Mechanism of Supramolecular Peptide Nanofibers and Its Correlation with Their Internal Viscosity.
Enzyme-responsive supramolecular peptide biomaterials have attracted growing interest for disease diagnostics and treatments. However, it remains unclear whether enzymes target the peptide assemblies or dissociated peptide monomers. To gain further insight into the degradation mechanism of supramolecular peptide amphiphile (PA) nanofibers, cathepsin B with both exopeptidase and endopeptidase activities was exploited here for degradation studies. Hydrolysis was found to occur directly on the PA nanofibers as only surface amino acid residues were cleaved. The number of cleaved residues and the degradation efficiency was observed to be negatively correlated with the internal viscosity of the PA nanofibers, quantified to be between 200-800 cP (liquid phase) using fluorescence lifetime imaging microscopy combined with an environmentally sensitive molecular rotor, BODIPY-C10. These findings enhance our understanding on the enzymatic degradation of supramolecular PA nanofibers and have important implications for the development of PA probes for the real-time monitoring of disease-related enzymes
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