2,350,890 research outputs found
Adsorption of proteins to thin-films of PDMS and its effect on the adhesion of human endothelial cells
This paper describes a simple and inexpensive procedure to produce thin-films of poly(dimethylsiloxane). Such films were characterized by a variety of techniques (ellipsometry, nuclear magnetic resonance, atomic force microscopy, and goniometry) and used to investigate the adsorption kinetics of three model proteins (fibrinogen, collagen type-I, and bovine serum albumin) under different conditions. The information collected from the protein adsorption studies was then used to investigate the adhesion of human dermal microvascular endothelial cells. The results of these studies suggest that these films can be used to model the surface properties of microdevices fabricated with commercial PDMS. Moreover, the paper provides guidelines to efficiently attach cells in BioMEMS devices.Fil: Chumbimuni Torres, Karin Y.. The University of Texas at San Antonio; Estados UnidosFil: Coronado, Ramon E.. The University of Texas at San Antonio; Estados UnidosFil: Mfuh, Adelphe M.. The University of Texas at San Antonio; Estados UnidosFil: Castro Guerrero, Carlos. The University of Texas at San Antonio; Estados UnidosFil: Silva, María Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Biología Agrícola de Mendoza. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Biología Agrícola de Mendoza; ArgentinaFil: Negrete, George R.. The University of Texas at San Antonio; Estados UnidosFil: Bizios, Rena. The University of Texas at San Antonio; Estados UnidosFil: Garcia, Carlos D.. The University of Texas at San Antonio; Estados Unido
The Halos of Satellite Galaxies: the Companion of the Massive Elliptical Lens SL2S J08544-0121
Strong gravitational lensing by groups or clusters of galaxies provides a
powerful technique to measure the dark matter properties of individual lens
galaxies. We study in detail the mass distribution of the satellite lens galaxy
in the group-scale lens SL2S J08544-0121 by modelling simultaneously the
spatially extended surface brightness distribution of the source galaxy and the
lens mass distribution using Markov chain Monte Carlo methods. In particular,
we measure the dark matter halo size of the satellite lens galaxy to be
6.0^{+2.9}_{-2.0} kpc with a fiducial velocity dispersion of 127^{+21}_{-12}
km/s. This is the first time the size of an individual galaxy halo in a galaxy
group has been measured using strong gravitational lensing without assumptions
of mass following light. We verify the robustness of our halo size measurement
using mock data resembling our lens system. Our measurement of the halo size is
compatible with the estimated tidal radius of the satellite galaxy, suggesting
that halos of galaxies in groups experience significant tidal stripping, a
process that has been previously observed on galaxies in clusters. Our mass
model of the satellite galaxy is elliptical with its major axis misaligned with
that of the light by ~50 deg. The major axis of the total matter distribution
is oriented more towards the centre of the host halo, exhibiting the radial
alignment found in N-body simulations and observational studies of satellite
galaxies. This misalignment between mass and light poses a significant
challenge to modified Newtonian dynamics.Comment: 13 pages, 10 figures, minor revisions based on referee's comments,
accepted for publication in A&
Possible evidence for the breakdown of the CKM-paradigm of CP-violation
Using primarily experimental inputs for S(B -> psi Ks), Delta M_Bs, Delta
M_Bd, BR(B -> tau nu) and epsilon_K along with necessary inputs from the
lattice, we find that the measured value of sin(2 beta) is smaller than
expectations of the Standard Model by as much as 3.3 sigma, and also that the
measured value of the BR(B -> tau nu) seems to be less than the predicted value
by about 2.8 sigma. However, through a critical study we show that most likely
the dominant source of these deviations is in B_d(s) mixings and in sin(2 beta)
and less so in B -> tau nu, and also that the bulk of the problem persists even
if input from epsilon_K is not used. The fact that kaon mixing and epsilon_K
are not the dominant source of the deviation from the Standard Model has the
very important consequence that model independent considerations imply that the
scale of the relevant new CP-violating physics is below O(2 TeV), thus
suggesting that direct signals of the new particle(s) may well be accessible in
collider experiments at the LHC and perhaps even at the Tevatron.Comment: 6 pages, 8 figures. Added another fit and some more discussion
showing that BR(B->tau nu) comes out in good agreement with predictions of
the SM if the measured value of sin2beta is not used as an input. References
adde
Cognitive Metaphors of the Mind in the Canterbury Tales
The paper presents an analysis of a number of cognitive metaphors pertaining to the concept of mind (e.g. sanity and insanity), heart, and fire. The study has been based on the text of Canterbury Tales by Geoffrey Chaucer. The paper contains a short theoretical introduction and a discussion of different linguistic and psychological approaches to issues related to figurative and literal, conventional language use. The analytical part focuses on the detailed contextual study of the cognitive metaphorical concepts. It is argued that many apparently similar concepts can evoke semantically conflicting metaphors, while concepts that appear to be mutually exclusive can sometimes evoke common associations and thereby similar metaphors
General CP Violation in Minimal Left-Right Symmetric Model and Constraints on the Right-Handed Scale
In minimal left-right symmetric theories, the requirement of parity
invariance allows only one complex phase in the Higgs potential and one in the
Yukawa couplings, leading to a two-phase theory with both spontaneous and
explicit CP violations. We present a systematic way to solve the right-handed
quark mixing matrix analytically in this model and find that the leading order
solution has the same hierarchical structure as the left-handed CKM matrix with
one more CP-violating phase coming from the complex Higgs vev. Armed with this
explicit right-handed mixing matrix, we explore its implications for flavor
changing and conserving processes in detail, low-energy CP-violating
observables in particular. We report an improved lower bound on the mass
of 2.5 TeV from and , and a somewhat higher bound (4
TeV) from kaon decay parameters , , and neutron electric
dipole moment. The new bound on the flavor-changing neutral Higgs mass is 25
TeV.Comment: 35 pages, 14 figure
On epsilon_K beyond lowest order in the Operator Product Expansion
We analyse the structure of long distance (LD) contributions to the
CP-violating parameter epsilon_K, that generally affect both the absorptive
(Gamma_12) and the dispersive (M_12) parts of the K0 -- K0bar mixing amplitude.
We point out that, in a consistent framework, in addition to LD contributions
to Im(Gamma_12), estimated recently by two of us, also LD contributions to
Im(M_12) have to be taken into account. Estimating the latter contributions the
impact of LD effects on epsilon_K is significantly reduced (from -6.0 % to -3.6
%). The overall effect of LD corrections and of the superweak phase being
different from 45 degrees is summarised by the multiplicative factor
kappa_epsilon = 0.94 +/- 0.02.Comment: 10 pages, 2 figures. v3: minor typos fixed. Matches journal versio
Local triple derivations on real C*-algebras and JB*-triples
We study when a local triple derivation on a real JB*-triple is a triple
derivation. We find an example of a (real linear) local triple derivation on a
rank-one Cartan factor of type I which is not a triple derivation. On the other
hand, we find sufficient conditions on a real JB*-triple E to guarantee that
every local triple derivation on E is a triple derivation
Orthogonal forms and orthogonality preservers on real function algebras
We initiate the study of orthogonal forms on a real C-algebra. Motivated
by previous contributions, due to Ylinen, Jajte, Paszkiewicz and Goldstein, we
prove that for every continuous orthogonal form on a commutative real
C-algebra, , there exist functionals and in
satisfying for every
in . We describe the general form of a (not-necessarily continuous)
orthogonality preserving linear map between unital commutative real
C-algebras. As a consequence, we show that every orthogonality preserving
linear bijection between unital commutative real C-algebras is continuous.Comment: To appear in Linear and Multilinear Algebr
2-local triple homomorphisms on von Neumann algebras and JBW-triples
We prove that every (not necessarily linear nor continuous) 2-local triple
homomorphism from a JBW-triple into a JB-triple is linear and a triple
homomorphism. Consequently, every 2-local triple homomorphism from a von
Neumann algebra (respectively, from a JBW-algebra) into a C-algebra
(respectively, into a JB-algebra) is linear and a triple homomorphism
Optimization of 3D ZnO brush-like nanorods for dye-sensitized solar cells
© 2018 The Royal Society of Chemistry This is an Open Access article, distributed under the terms of the Creative Commons Attribution Unported 3.0 license (CC BY 3.0), https://creativecommons.org/licenses/by/3.0/ which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly citedIn a dye-sensitized solar cell (DSSC) the amount of adsorbed dye on the photoanode surface is a key factor that must be maximized in order to obtain enhanced DSSC performance. In this study 3D ZnO nanostructures, named brush-like, are demonstrated as alternative photoanodes. In these structures, long ZnO nanorods are covered with a metal-organic precursor, known as a layered-hydroxide zinc salt (LHZS), which is subsequently converted to crystalline ZnO using two-step annealing. The LHZS is able to easily grow on any surface, such as the ZnO nanorod surface, without needing the assistance of a seed-layer. Brush-like structures synthesized using different citrate concentrations in the growth solutions and different annealing conditions are characterized and tested as DSSC photoanodes. The best-performing structure reported in this study was obtained using the highest citrate concentration (1.808 mM) and the lowest temperature annealing condition in an oxidative environment. Conversion efficiency as high as 1.95% was obtained when these brush-like structures were employed as DSSC photoanodes. These results are extremely promising for the implementation of these innovative structures in enhanced DSSCs, as well as in other applications that require the maximization of surface area exposed by ZnO or similar semiconductors, such as gas- or bio-sensing or photocatalysis.Peer reviewedFinal Published versio
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