2,273 research outputs found
Effective Action and Holography in 5D Gauge Theories
We apply the holographic method to 5D gauge theories on the warped interval.
Our treatment includes the scalars associated with the fifth gauge field
component, which appear as 4D Goldstone bosons in the holographic effective
action. Applications are considered to two classes of models in which these
scalars play an important role. In the Composite-Higgs (and/or Gauge-Higgs
Unification) scenario, the scalars are interpreted as the Higgs field and we
use the holographic recipe to compute its one-loop potential. In AdS/QCD
models, the scalars are identified with the mesons and we compute
holographically the Chiral Perturbation Theory Lagrangian up to p^4 order. We
also discuss, using the holographic perspective, the effect of including a
Chern-Simons term in the 5D gauge Lagrangian. We show that it makes a
Wess-Zumino-Witten term to appear in the holographic effective action. This is
immediately applied to AdS/QCD, where a Chern-Simons term is needed in order to
mimic the Adler-Bardeen chiral anomaly.Comment: 37 pages; v2, minor changes, one reference added; v3, minor
corrections, version published in JHE
Simple and Realistic Composite Higgs Models in Flat Extra Dimensions
We construct new composite Higgs/gauge-Higgs unification (GHU) models in flat
space that overcome all the difficulties found in the past in attempting to
construct models of this sort. The key ingredient is the introduction of large
boundary kinetic terms for gauge (and fermion) fields. We focus our analysis on
the electroweak symmetry breaking pattern and the electroweak precision tests
and show how both are compatible with each other. Our models can be seen as
effective TeV descriptions of analogue warped models. We point out that, as far
as electroweak TeV scale physics is concerned, one can rely on simple and more
flexible flat space models rather than considering their unavoidably more
complicated warped space counterparts. The generic collider signatures of our
models are essentially undistinguishable from those expected from composite
Higgs/warped GHU models, namely a light Higgs, colored fermion resonances below
the TeV scale and sizable deviations to the Higgs and top coupling.Comment: 30 figures, 9 figures; v2: minor improvements, one reference added,
version to appear in JHE
Mapping the complete glycoproteome of virion-derived HIV-1 gp120 provides insights into broadly neutralizing antibody binding
The surface envelope glycoprotein (SU) of Human immunodeficiency virus type 1 (HIV-1), gp120SU plays an essential role in virus binding to target CD4+ T-cells and is a major vaccine target. Gp120 has remarkably high levels of N-linked glycosylation and there is considerable evidence that this “glycan shield” can help protect the virus from antibody-mediated neutralization. In recent years, however, it has become clear that gp120 glycosylation can also be included in the targets of recognition by some of the most potent broadly neutralizing antibodies. Knowing the site-specific glycosylation of gp120 can facilitate the rational design of glycopeptide antigens for HIV vaccine development. While most prior studies have focused on glycan analysis of recombinant forms of gp120, here we report the first systematic glycosylation site analysis of gp120 derived from virions produced by infected T lymphoid cells and show that a single site is exclusively substituted with complex glycans. These results should help guide the design of vaccine immunogens
AdS/QCD: The Relevance of the Geometry
We investigate the relevance of the metric and of the geometry in
five-dimensional models of hadrons. Generically, the metric does not affect
strongly the results and even flat space agrees reasonably well with the data.
Nevertheless, we observe a preference for a decreasing warp factor, for example
AdS space. The Sakai-Sugimoto model reduces to one of these models and the
level of agreement is similar to the one of flat space. We also consider the
discrete version of the five-dimensional models, obtained by dimensional
deconstruction. We find that essentially all the relevant features of
"holographic" models of QCD can be reproduced with a simple 3-site model
describing only the states below the cut-off of the theory.Comment: 25 pages + appendix. v2 minor changes and Refs. adde
On electroweak baryogenesis in the littlest Higgs model with T parity
We study electroweak baryogenesis within the framework of the littlest Higgs
model with T parity. This model has shown characteristics of a strong
first-order electroweak phase transition, which is conducive to baryogenesis in
the early Universe. In the T parity symmetric theory, there are two gauge
sectors, viz., the T-even and the T-odd ones. We observe that the effect of the
T-parity symmetric interactions between the T-odd and the T-even gauge bosons
on gauge-higgs energy functional is quite small, so that these two sectors can
be taken to be independent. The T-even gauge bosons behave like the Standard
Model gauge bosons, whereas the T-odd ones are instrumental in stabilizing the
Higgs mass. For the T-odd gauge bosons in the symmetric and asymmetric phases
and for the T-even gauge bosons in the asymmetric phase, we obtain, using the
formalism of Arnold and McLerran, very small values of the ratio, (Baryon
number violation rate/Universe expansion rate). We observe that this result, in
conjunction with the scenario of inverse phase transition in the present work
and the value of the ratio obtained from the lattice result of sphaleron
transition rate in the symmetric phase, can provide us with a plausible
baryogenesis scenario.Comment: 13 pages, 2 figures, published version, references modifie
Oral carcinogenesis biomarkers in Oral Chronic Mechanical Irritation-associated lesions
Previous works of our team had shown clinical data which suggest that Chronic Mechanical Irritation (CMI) could be a risk factor for Oral Cancer (OC). However, there are no known patterns of biomarkers in CMI indicative of cellular malignancy. The aim of this study was to identify a biomarker pattern of differentiation (Ck19) and cell proliferation (Ki67) in CMI-associated lesions, similar to those observed in OC. Methods: a Cross-sectional study of adult patients (n = 61), both sexes, with lesions associated with CMI according to the Piemonte et al criteria. CK19 and Ki67 Immunohistochemistry were carried out in biopsies of both types of lesions and the patterns were described according to previous publications of Safadi and Argyris. The present study was approved by Ethics Committee of the College of Dentistry, Universidad Nacional de Cordoba. Results: Ki67 overexpression and a CK19 focal pattern with strong intensity in basal and parabasal cells were observed in CMI lesions, similar to that observed in OC. Conclusion: there is no scientific literature on biomarker patterns of Oral CMI. Therefore, the described pattern, particularly Ck19, is novel and could be indicative of the relationship between the presence of CMI and oral carcinogenesis.Fil: Gilligan, Gerardo Marcelo. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra de Estomatología A; Argentina.Fil: Piemonte, Eduardo David. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra de Estomatología A; Argentina.Fil: Panico, René Luis. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra de Estomatología A; Argentina.Fil: Di Tada, Cecilia E. Fundación para el progreso de la Medicina; Argentina.Fil: Di Tada, Cecilia E.. Universidad Nacional de Córdoba. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Química Biológica; Argentina.Fil: Brunotto, Mabel. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra Biología Celular A; Argentina.Otras Ciencias de la Salu
Effective description of brane terms in extra dimensions
We study how theories defined in (extra-dimensional) spaces with localized
defects can be described perturbatively by effective field theories in which
the width of the defects vanishes. These effective theories must incorporate a
``classical'' renormalization, and we propose a renormalization prescription a
la dimensional regularization for codimension 1, which can be easily used in
phenomenological applications. As a check of the validity of this setting, we
compare some general predictions of the renormalized effective theory with
those obtained in a particular ultraviolet completion based on deconstruction.Comment: 28 page
Epigenome-wide association study reveals decreased average methylation levels years before breast cancer diagnosis
Interest in the potential of DNA methylation in peripheral blood as a biomarker of cancer risk is increasing. We aimed to assess whether epigenome-wide DNA methylation measured in peripheral blood samples obtained before onset of the disease is associated with increased risk of breast cancer. We report on three independent prospective nested case-control studies from the European Prospective Investigation into Cancer and Nutrition (EPIC-Italy; n = 162 matched case-control pairs), the Norwegian Women and Cancer study (NOWAC; n = 168 matched pairs), and the Breakthrough Generations Study (BGS; n = 548 matched pairs). We used the Illumina 450k array to measure methylation in the EPIC and NOWAC cohorts. Whole-genome bisulphite sequencing (WGBS) was performed on the BGS cohort using pooled DNA samples, combined to reach 50× coverage across ~16 million CpG sites in the genome including 450k array CpG sites. Mean β values over all probes were calculated as a measurement for epigenome-wide methylation
Paradise lost?: Understanding social embeddedness through crisis and violence in the Neapolitan “Land of Fires”
This is the author accepted manuscript. The final version is available from IGI Global via the DOI in this recordSince the mid-90s three million people living in the metropolitan area of Naples (Italy) have been facing one of the most dramatic socio-ecological crisis witnessed in Western Europe. This is a crisis orchestrated by Mafia-like organizations (e.g. the Neapolitan Mafia also known as Camorra) and their interest in the illegal management of waste disposal and incineration in the shadow of a weak state, a phenomenon often referred to as the ‘Land of Fires’. Using evidence from this prolonged socio-ecological crisis, in this chapter, we attempt to inductively mobilise the Polanyian notion of embeddedness, to understand the establishment and expansion of a waste economy in diffused violent social and economic relations. We particularly attempt to extend the notion of ‘embedded economy’, building on the work of Karl Polanyi (1944). We argue that the process of social embeddedness through illegal and violent practices are particularly intense in contexts of socio-ecological crises, where the expropriation of land and destruction of nature is coupled with the disarticulation of the role of the state by criminal organizations.ECOREME
Anomalous Couplings in Double Higgs Production
The process of gluon-initiated double Higgs production is sensitive to
non-linear interactions of the Higgs boson. In the context of the Standard
Model, studies of this process focused on the extraction of the Higgs trilinear
coupling. In a general parametrization of New Physics effects, however, an even
more interesting interaction that can be tested through this channel is the
(ttbar hh) coupling. This interaction vanishes in the Standard Model and is a
genuine signature of theories in which the Higgs boson emerges from a
strongly-interacting sector. In this paper we perform a model-independent
estimate of the LHC potential to detect anomalous Higgs couplings in
gluon-fusion double Higgs production. We find that while the sensitivity to the
trilinear is poor, the perspectives of measuring the new (ttbar hh) coupling
are rather promising.Comment: 22 pages, 9 figures. v2: plots of Figs.8 and 9 redone to include
experimental uncertainty on the Higgs couplings, references adde
- …