10,919 research outputs found
Protein adsorption on heterogeneous surfaces
The adsorption of the protein bovine serum albumin from an aqueous solution onto substrata made from pure silica, pure zirconia, and a mixture of the two has revealed that the adsorption behavior of the protein onto the mixture very significantly diverges from the corresponding mean of the behaviors with the pure substrata. A tentative explanation in terms of matching substratum heterogeneity with protein surface heterogeneity is offered
A preliminary look at AVE-SESAME 1 conducted on 10-11 April 1979
Preliminary information on the general weather conditions during the AVE-SESAME 1 period is presented together with a summary of severe weather reports
Chiral Properties of Pseudoscalar Mesons on a Quenched Lattice with Overlap Fermions
The chiral properties of the pseudoscalar mesons are studied numerically on a
quenched lattice with the overlap fermion. We elucidate the role of the
zero modes in the meson propagators, particularly that of the pseudoscalar
meson. The non-perturbative renormalization constant is determined from
the axial Ward identity and is found to be almost independent of the quark mass
for the range of quark masses we study; this implies that the error is
small. The pion decay constant, , is calculated from which we
determine the lattice spacing to be 0.148 fm. We look for quenched chiral log
in the pseudoscalar decay constants and the pseudoscalar masses and we find
clear evidence for its presence. The chiral log parameter is
determined to be in the range 0.15 -- 0.4 which is consistent with that
predicted from quenched chiral perturbation theory.Comment: Version accepted for publication by PRD. A few minor typographical
errors have been corrected. 24 pages, 11 figure
Color-flavor locked strange matter
We analyze how the CFL states in dense matter work in the direction of
enhancing the parameter space for absolutely stable phases (strange matter). We
find that the "CFL strange matter" phase can be the true ground state of
hadronic matter for a much wider range of the parameters of the model (the gap
of the QCD Cooper pairs , the strange quark mass and the Bag
Constant ) than the state without any pairing, and derive a full equation of
state and an accurate analytic approximation to the lowest order in
and which may be directly used for applications. The effects of pairing
on the equation of state are found to be small (as previously expected) but not
negligible and may be relevant for astrophysics.Comment: 5 pages, 2 figure
Uncovering Low-Dimensional Topological Structure in the QCD Vacuum
Recently, we have pointed out that sign-coherent 4-dimensional structures can
not dominate topological charge fluctuations in QCD vacuum at all scales. Here
we show that an enhanced lower-dimensional coherence is possible. In pure SU(3)
lattice gauge theory we find that in a typical equilibrium configuration about
80% of space-time points are covered by two oppositely-charged connected
structures built of elementary 3-dimensional coherent hypercubes. The
hypercubes within the structure are connected through 2-dimensional common
faces. We suggest that this coherence is a manifestation of a low-dimensional
order present in the QCD vacuum. The use of a topological charge density
associated with Ginsparg-Wilson fermions ("chiral smoothing") is crucial for
observing this structure.Comment: 3 pages, 1 figure; Proceedings of the "Confinement V" Conference,
Gargnano, Italy, Sep 10-14, 200
The Negativity of the Overlap-Based Topological Charge Density Correlator in Pure-Glue QCD and the Non-Integrable Nature of its Contact Part
We calculate the lattice two-point function of topological charge density in
pure-glue QCD using the discretization of the operator based on the overlap
Dirac matrix. Utilizing data at three lattice spacings it is shown that the
continuum limit of the correlator complies with the requirement of
non-positivity at non-zero distances. For our choice of the overlap operator
and the Iwasaki gauge action we find that the size of the positive core is ~2a
(with a being the lattice spacing) sufficiently close to the continuum limit.
This result confirms that the overlap-based topological charge density is a
valid local operator over realistic backgrounds contributing to the QCD path
integral, and is important for the consistency of recent results indicating the
existence of a low-dimensional global brane-like topological structure in the
QCD vacuum. We also confirm the divergent short-distance behavior of the
correlator, and the non-integrable nature of the associated contact part.Comment: 13 pages, 5 figure
“Basically... porn is everywhere”: a rapid evidence assessment on the effects that access and exposure to pornography has on children and young people
This Rapid Evidence Assessment (REA) was commissioned by the Office of the Children’s Commissioner (OCC) as part of its Inquiry into Child Sexual Exploitation in Gangs and Groups (CSEGG). It was conducted by a consortium led by Middlesex University, to explore the effects that exposure and access to pornography have on children and young people. The CSEGG Inquiry was launched in October 2011 to better understand the scale, scope, extent and nature of child sexual exploitation in gangs and groups. An emergent issue was whether accessing and viewing pornography can have an impact on children and young people’s expectations and attitudes towards sexual activity and relationships. Despite limited recourse to previous evidence, professionals interviewed over the course of the CSEGG Inquiry raised concerns about the impact of pornography at 43 per cent of site visits and 48 per cent of evidence hearings (Berelowitz et al., 2012).
Professionals from many agencies reported particular concerns about the effects of pornography involving high levels of degradation, violence and humiliation, which they believe to be prevalent in material freely available online. Police case files that were reviewed cited instances of boys and young men referring to pornography during sexual assaults (Berelowitz et al., 2012). This REA was therefore commissioned to inform the CSEGG Inquiry Chair, Panel and Project Team, enabling them to add depth to their ultimate recommendations regarding child sexual exploitation in gangs and groups
Comparison of ATP binding sites using structure-based similarity methods and molecular interaction fields
- …