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The Immunological Basis of Dry Eye Disease and Current Topical Treatment Options.
Homeostasis of the lacrimal functional unit is needed to ensure a well-regulated ocular immune response comprising innate and adaptive phases. When the ocular immune system is excessively stimulated and/or immunoregulatory mechanisms are disrupted, the balance between innate and adaptive phases is dysregulated and chronic ocular surface inflammation can result, leading to chronic dry eye disease (DED). According to the Tear Film and Ocular Surface Society Dry Eye Workshop II definition, DED is a multifactorial disorder of the ocular surface characterized by impairment and loss of tear homeostasis (hyperosmolarity), ocular discomfort or pain, and neurosensory abnormalities. Dysregulated ocular immune responses result in ocular surface damage, which is a further contributing factor to DED pathology. Several therapeutics are available to break the vicious circle of DED and prevent chronic disease and progression, including immunosuppressive agents (steroids) and immunomodulators (cyclosporine and lifitegrast). Given the chronic inflammatory nature of DED, each of these agents is commonly used in clinical practice. In this study, we review the immunopathology of DED and the molecular and cellular actions of current topical DED therapeutics to inform clinical decision making
Perspectives on Quantum Gravity Phenomenology
The idea that quantum gravity manifestations would be associated with a
violation of Lorentz invariance is very strongly bounded and faces serious
theoretical challenges. Other related ideas seem to be drowning in
interpretational quagmires. This leads us to consider alternative lines of
thought for such phenomenological search. We discuss the underlying viewpoints
and briefly mention their possible connections with other current theoretical
ideas.Comment: Latex, 23 page
The Seeds of Cosmic structure as a door to New Physics
There is something missing in our understanding of the origin of the seeds of
Cosmic Structuture.
The fact that the fluctuation spectrum can be extracted from the inflationary
scenario through an analysis that involves quantum field theory in curved
space-time, and that it coincides with the observational data has lead to a
certain complacency in the community, which prevents the critical analysis of
the obscure spots in the derivation. The point is that the inhomogeneity and
anisotropy of our universe seem to emerge from an exactly homogeneous and
isotropic initial state through processes that do not break those symmetries.
This article gives a brief recount of the problems faced by the arguments based
on established physics, which comprise the point of view held by a large
majority of researchers in the field.
The conclusion is that we need some new physics to be able to fully address
the problem. The article then exposes one avenue that has been used to address
the central issue and elaborates on the degree to which, the new approach makes
different predictions from the standard analyses.
The approach is inspired on Penrose's proposals that Quantum Gravity might
lead to a real, dynamical collapse of the wave function, a process that we
argue has the properties needed to extract us from the theoretical impasse
described above.Comment: Prepared for the proceedings of the conference NEBXII " Recent
Developments in Gravity", Napfio Grece June 2006. LateX, 15 page
Computation of topological phase diagram of disordered PbSnTe using the kernel polynomial method
We present an algorithm to determine topological invariants of inhomogeneous
systems, such as alloys, disordered crystals, or amorphous systems. Based on
the kernel polynomial method, our algorithm allows us to study samples with
more than degrees of freedom. Our method enables the study of large
complex compounds, where disorder is inherent to the system. We use it to
analyse PbSnTe and tighten the critical concentration for the
phase transition.Comment: 4 pages + supplemental materia
NuSTAR Tests of Sterile-Neutrino Dark Matter: New Galactic Bulge Observations and Combined Impact
We analyze two dedicated NuSTAR observations with exposure ks
located from the Galactic plane, one above and the other
below, to search for x-ray lines from the radiative decay of sterile-neutrino
dark matter. These fields were chosen to minimize astrophysical x-ray
backgrounds while remaining near the densest region of the dark matter halo. We
find no evidence of anomalous x-ray lines in the energy range 5--20 keV,
corresponding to sterile neutrino masses 10--40 keV. Interpreted in the context
of sterile neutrinos produced via neutrino mixing, these observations provide
the leading constraints in the mass range 10--12 keV, improving upon previous
constraints in this range by a factor . We also compare our results to
Monte Carlo simulations, showing that the fluctuations in our derived limit are
not dominated by systematic effects. An updated model of the instrumental
background, which is currently under development, will improve NuSTAR's
sensitivity to anomalous x-ray lines, particularly for energies 3--5 keV.Comment: 16 pages, 5 figures. Text updated to match published version in PRD.
Conclusions unchange
A signature of quantum gravity at the source of the seeds of cosmic structure?
This article reviews a recent work by a couple of colleagues and myself about
the shortcomings of the standard explanations of the quantum origin of cosmic
structure in the inflationary scenario, and a proposal to address them. The
point it that in the usual accounts the inhomogeneity and anisotropy of our
universe seem to emerge from an exactly homogeneous and isotropic initial state
through processes that do not break those symmetries. We argued that some novel
aspect of physics must be called upon to able to address the problem in a fully
satisfactory way. The proposed approach is inspired on Penrose's ideas
regarding an quantum gravity induced, real and dynamical collapse of the wave
function.Comment: LateX, (jpconference macros), Prepared for the proceedings the Third
International Workshop DICE 2006, " Quantum Mechanics between decoherence and
Determinism
Entropy in the Classical and Quantum Polymer Black Hole Models
We investigate the entropy counting for black hole horizons in loop quantum
gravity (LQG). We argue that the space of 3d closed polyhedra is the classical
counterpart of the space of SU(2) intertwiners at the quantum level. Then
computing the entropy for the boundary horizon amounts to calculating the
density of polyhedra or the number of intertwiners at fixed total area.
Following the previous work arXiv:1011.5628, we dub these the classical and
quantum polymer models for isolated horizons in LQG. We provide exact
micro-canonical calculations for both models and we show that the classical
counting of polyhedra accounts for most of the features of the intertwiner
counting (leading order entropy and log-correction), thus providing us with a
simpler model to further investigate correlations and dynamics. To illustrate
this, we also produce an exact formula for the dimension of the intertwiner
space as a density of "almost-closed polyhedra".Comment: 24 page
Cartography interpreted of soil : San Carlos, Mendoza (Argentina)
El objetivo del trabajo fue generar mapas y asociarlos a bases de datos digitales donde se puedan consultar, en forma automatizada y eficiente, preguntas temáticas y por localización. No importa la cartografía en sí misma, sino el análisis, la interpretación y el establecimiento de indicadores de aptitudes edáficas a partir de información geográfica sistematizada. La Información básica es confiable y posee la máxima integridad. Con IDRISI se realizó, con las bandas 5, 4 Y 3 una composición en falso color. Se elaboraron mapas digitalizados de clasificación no supervisada de cobertura del suelo. Se confeccionó, en Access, una base de datos con 26 registros de determinaciones edáficas. Se exportó esta información temática a IDRISI versión 2.0. Con IDRISI se cartografiaron diferentes campos de la base de datos, lo que estableció distintas zonas pilotos en las que se realizó análisis espacial. De estos análisis se crearon mapas temáticos en formato digital. Con otra base de datos reales de 20 registros se convalidaron los resultados de las cartografías realizadas.
El trabajo expresa una visión general real de las características edáficas superficiales más importantes y las cartografías cas realizadas tienen valor práctico al establecer indicadores que sirven para quienes tengan conocimientos edafológicos medios.The objective of the work is to generate maps and to associate them to digital databases. Where the databas es are immediately available and thematic and localization questions can be consulted in automated, efficient and effective formo The basis is not only the cartography by itself but also to analyse, to interpret, to create knowledge, to set indicators of edaphic aptitudes, starting from the data and systematized geographical information. The basic information is reliable and it possesses the maximum integrity. With IDRISI a composition in false color, with the bands 5, 4 and 3 was carried out. Digitized maps of not supervised classification of covering of the soil were elaborated. In Access a database with 26 registrations of edaphic determinations was created. Thematic information was exported to IDRIS1 version 2:0. In IDRISI different fields of the database were established different control areas in those that space analyses was carried out. From these analyses thematic maps were created in digital formato With another database of 20 registrations, the results of temáti¬ the carried out cartographies was authenticated.
The work expresses a general vision of the most important characteristic of surface soil and the thematic cartographies carried out have an important practical value, specially for those who have average edaphic knowledge.Fil: Perez Valenzuela, Benjamín R..
Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: De Cara, Daniel E. .
Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: Lipinski, Víctor M. .
Universidad Nacional de Cuyo. Facultad de Ciencias Agraria
Criticality without frustration for quantum spin-1 chains
Frustration-free (FF) spin chains have a property that their ground state
minimizes all individual terms in the chain Hamiltonian. We ask how entangled
the ground state of a FF quantum spin-s chain with nearest-neighbor
interactions can be for small values of s. While FF spin-1/2 chains are known
to have unentangled ground states, the case s=1 remains less explored. We
propose the first example of a FF translation-invariant spin-1 chain that has a
unique highly entangled ground state and exhibits some signatures of a critical
behavior. The ground state can be viewed as the uniform superposition of
balanced strings of left and right parentheses separated by empty spaces.
Entanglement entropy of one half of the chain scales as log(n)/2 + O(1), where
n is the number of spins. We prove that the energy gap above the ground state
is polynomial in 1/n. The proof relies on a new result concerning statistics of
Dyck paths which might be of independent interest.Comment: 11 pages, 2 figures. Version 2: minor changes in the proof of Lemma
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