Rho meson decay width in SU(2) gauge theories with 2 fundamental flavours

7 pages, Proceedings of the 34th International Symposium on Lattice Field Theory (Lattice 2016)SU(2) gauge theories with two quark flavours in the fundamental representation are among the most promising theories of composite dynamics describing the electroweak sector. Three out of five Goldstone bosons in these models become the longitudinal components of the W and Z bosons giving them mass. Like in QCD, we expect a spectrum of excitations which appear as resonances in vector boson scattering, in particular the vector resonance corresponding to the rho-meson in QCD. In this talk I will present the preliminary results of the first calculation of the rho-meson decay width in this theory, which is analogous to rho to two pions decay calculation in QCD. The results presented were calculated in a moving frame with total momentum (0,0,1) on two ensembles. Future plans include using 3 moving frames on a larger set of ensembles to extract the resonance parameters more reliably and also take the chiral and continuum limits

Policy Monitoring on Accessible Technology for Inclusive Education – Research Findings and Requirements for a Software Tool

Statistics about disabled people usually do not receive as much attention as statistics highlighting other socio-economic problems. However, such statistics is important due to its actual weight. According to the World Health Organization (WHO), about 15% of the world population, meaning one billion people, live with disabilities, and 80% of them live in developing countries. UNESCO claims that 90% of the children with disabilities in developing countries do not attend schools. Thus, it is of upmost relevance to raise awareness and strengthen public policies for the use of Assistive Technology (AT) to ensure Inclusive Education and Access to Information for people with disabilities, particularly in developing countries. Contributing to such efforts, this paper presents research findings on policy monitoring and evaluation tools and defines requirements for a software tool for monitoring a public policy for the use of AT to ensure Inclusive Education and Access to Information for persons with visual and hearing impairments, with particular focus on Uganda. The research findings and tool requirements presented in this paper could be adapted by other countries that pursue such policies.Facultad de Informátic

Effect of environmental weathering on flexural creep behavior of long fiber-reinforced thermoplastic composites

Flexural creep behavior of nylon 6/6 (NY66)- and polypropylene (PP)- based long fiber (l/d = 2000-10 000) thermoplastic (LFT) composites was investigated as a function of ultraviolet irradiation and moisture absorption. Extrusion/compression-molded panels were prepared according to ASTM D-2990 and conditioned according to ASTM D-618. NY66 and PP LFTs were characterized using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and Fourier-transform infrared (FTIR) spectroscopy in the unexposed condition, and as-exposed to 253.7 nm UV radiation. The creep compliance of PP LFT increased with increasing UV exposure, whereas the creep compliance of NY66 LFT showed a moderate decrease with increasing UV exposure. Moisture absorption experiments were performed in boiling water until saturation on NY66 and its LFT composites. Characterization of desorbed moisture absorption specimens suggested slight variation in the structure, and an analysis of creep compliances showed minimal changes as compared to the dry/unexposed specimens

Resonance study of SU(2) model with 2 fundamental flavours of fermions

Proceedings of 37th International Symposium on Lattice Field Theory - Lattice2019, 7 pagesComposite Higgs models are promising candidate models to address the long-standing naturalness problem in the Standard Model. Among them, the most minimal one is the SU(2) with 2 flavours of fermions in the fundamental representation of the gauge group. An important prediction in these models is the existence of resonance spectrum in vector boson scattering. Here we study the lowest such resonance, which is the equivalent of rho resonance in QCD. We describe the scan of the parameter space using the clover-improved Wilson fermions with Symanzik improved gauge action and then show the first results for the mass and width of the rho resonance in this model

The Glueball in a Chiral Linear Sigma Model with Vector Mesons

We present a two-flavour linear sigma model with global chiral symmetry and (axial-)vector mesons as well as an additional glueball degree of freedom. We study the structure of the well-established scalar resonances f0(1370) and f0(1500): by a fit to experimentally known decay widths we find that f0(1370) is predominantly a \bar{q}q state and f0(1500) is predominantly a glueball state. The overall phenomenology of these two resonances can be well described. Other assignments for our mixed quarkonium-glueball states are also tested, but turn out to be in worse agreement with the phenomenology. As a by-product of our analysis, the gluon condensate is determined.Comment: 8 page

Scattering of Goldstone bosons and resonance production in a composite Higgs model on the lattice

Abstract We calculate the coupling between a vector resonance and two Goldstone bosons in SU(2) gauge theory with Nf = 2 Dirac fermions in the fundamental representation. The considered theory can be used to construct a minimal Composite Higgs models. The coupling is related to the width of the vector resonance and we determine it by simulating the scattering of two Goldstone bosons where the resonance is produced. The resulting coupling is gVPP = 7.8 ± 0.6, not far from gρππ ≃ 6 in QCD. This is the first lattice calculation of the resonance properties for a minimal UV completion. This coupling controls the production cross section of the lightest expected resonance at the LHC and enters into other tests of the Standard Model, from Vector Boson Fusion to electroweak precision tests. Our prediction is crucial to constrain the model using lattice input and for understanding the behavior of the vector meson production cross section as a function of the underlying gauge theory. We also extract the coupling $${g}_{\mathrm{VPP}}^{\mathrm{KSRF}}$$ g VPP KSRF = 9.4 ± 0.6 assuming the vector-dominance and find that this phenomenological estimate slightly overestimates the value of the coupling.</jats:p

Policy Monitoring on Accessible Technology for Inclusive Education – Research Findings and Requirements for a Software Tool

Statistics about disabled people usually do not receive as much attention as statistics highlighting other socio-economic problems. However, such statistics is important due to its actual weight. According to the World Health Organization (WHO), about 15% of the world population, meaning one billion people, live with disabilities, and 80% of them live in developing countries. UNESCO claims that 90% of the children with disabilities in developing countries do not attend schools. Thus, it is of upmost relevance to raise awareness and strengthen public policies for the use of Assistive Technology (AT) to ensure Inclusive Education and Access to Information for people with disabilities, particularly in developing countries. Contributing to such efforts, this paper presents research findings on policy monitoring and evaluation tools and defines requirements for a software tool for monitoring a public policy for the use of AT to ensure Inclusive Education and Access to Information for persons with visual and hearing impairments, with particular focus on Uganda. The research findings and tool requirements presented in this paper could be adapted by other countries that pursue such policies.Facultad de Informátic

Promoter targeted small RNAs induce long-term transcriptional gene silencing in human cells

Small RNAs targeted to gene promoters in human cells can mediate transcriptional gene silencing (TGS) by directing silent state epigenetic modifications to targeted loci. Many mechanistic details of this process remain poorly defined, and the ability to stably modulate gene expression in this manner has not been explored. Here we describe the mechanisms of establishment and maintenance of long-term transcriptional silencing of the human ubiquitin C gene (UbC). Sustained targeting of the UbC promoter with a small RNA for a minimum of 3 days resulted in long-term silencing which correlated with an early increase in histone methylation and a later increase in DNA methylation at the targeted locus. Transcriptional silencing of UbC required the presence of a promoter-associated RNA. The establishment and maintenance of the TGS were shown to require distinct protein factors. Argonaute 1 (Ago1), DNA methyltransferase 3a (DNMT3a) and histone deacetylase 1 (HDAC1) were required for the initiation of silencing, and DNA methyltransferase 1 (DNMT1) was necessary for maintenance. Taken together the data presented here highlight the cellular pathway with which noncoding RNAs interact to epigenetically regulate gene expression in human cells

An RNA targeted to the HIV-1 LTR promoter modulates indiscriminate off-target gene activation

Transcriptional gene silencing (TGS) can be achieved by small RNAs targeted to upstream promoter regions. Previously we characterized siRNAs targeted to the HIV-1 long terminal repeat (LTR) promoter at site 247, and found that a 21-base antisense strand of siRNA-247 (LTR-247as) suppressed LTR-mediated expression. To characterize the specificity of LTR-247as, vectors expressing antisense RNAs targeted to a region spanning 50 bases up- and downstream of the 247 target site were generated. LTR-247as+7, a ∼22 base antisense RNA that is shifted by only seven bases upstream of LTR-247as, showed a significant increase in LTR-driven reporter gene expression that was independent of cell type and active chromatin methyl-marks. Promoter-targeting siRNAs have been recently shown to induce gene activation. However, here we demonstrate gene activation via a sequence-specific off-target effect. Microarray analysis of LTR-247as+7-treated cultures resulted in the deregulation of ∼185 genes. A gene of unknown function, C10orf76, was responsive to inhibition by LTR-247as+7 and the loss of C10orf76 resulted in the upregulation of several genes that were activated by LTR-247as+7. These data suggest caution when using short antisense RNAs or siRNAs designed to target promoter sequences, since promoter-targeted RNAs may have unintended inhibitory effects against factors with suppressive gene activity