Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente

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Ultra processed foods (UFAs) are becoming increasingly important in children´s diets, deteriorating their health and quality of life in the short, medium and long term. This study analysed the frequency of consumption of UPAs in 5th and 6th grade schoolchildren from three schools in three localities with different levels of urbanisation and socio-productive activities, Centenario (Neuquén), San Luis (San Luis) and Serrano (Cordoba), according to socio-demographic characteristics and food environments, in the year 2021. A descriptive, observational, cross-sectional study was conducted in a sample of 188 school children (San Luis n=76; Centenario n=62; Serrano n=50), who responded to a self- administered digital survey on the frequency of weekly consumption of UPA in main meals and snacks, socio-economic level (SEL) of the household and food environments (home and school). Comparison of proportions tests were applied to compare consumption frequency between locations and by SEL (significance level=0.005). Statistical analyses were performed with Stata V14.0 and EPIDAT. The group with the highest frequency of consumption was sweet biscuits (72.3%), where Centenario (n=33) showed higher consumption than Serrano (n=23) and San Luis (n=16) (p=0.001). Flavoured juices were consumed by a high percentage of school children within the group of sweetened beverages (71.2%). Serrano had the highest numbers of school children with very frequent consumption and the differences between Serrano (n=21) and Centenario (n=14) (p=0.045), and San Luis (n=16) (p=0.020) were significant. Finally, the group of sauces/dressings was consumed more than four times a week by a high proportion of school children (65.2%), where Serrano (n=25) had higher consumption than Centenario (n=16) (p=0.014) and San Luis (n=22) (p=0.027). No significant differences were found when analysing these products according to SEL. Finally, the main environment where UPAs were consumed was at home and the highest percentage (56.91%) consumed them during snack time. The results show that schoolchildren living in less urbanised localities had higher intakes of UPA, suggesting that both locality of residence and socio- economic background influence dietary choices and behaviours.Los alimentos ultraprocesados (AUP) son cada vez más protagonistas de la alimentación infantil deteriorando la salud y calidad de vida a corto, mediano y largo plazo. Este trabajo analizó la frecuencia de consumo de AUP en escolares de 5° y 6° grado, de tres escuelas de tres localidades con grado de urbanización y actividades socioproductivas diferentes entre sí, Centenario (Neuquén), San Luis (San Luis) y Serrano (Córdoba), según características sociodemográficas y entornos alimentarios, en el año 2021. Se realizó un estudio descriptivo, observacional, de corte transversal en una muestra de 188 escolares (San Luis n=76; Centenario n=62; Serrano n=50), quienes respondieron una encuesta digital autoadministrada sobre la frecuencia de consumo semanal de AUP en comidas principales y colaciones, nivel socioeconómico (NSE) del hogar y entornos alimentarios (hogar y escuela). Se aplicaron pruebas de comparación de proporciones para comparar la frecuencia de consumo entre localidades y por NSE (nivel de significación=0,05). Los análisis estadísticos se realizaron con Stata V14.0 y EPIDAT. El grupo con mayor frecuencia de consumo fueron las galletas dulces (72,3%), donde Centenario (n=33) presentó mayor consumo que Serrano (n=23) y San Luis (n=16) (p=0,001). Los jugos saborizados fueron consumidos por un alto porcentaje de escolares, dentro del grupo bebidas azucaradas (71,2%) registrando diferencias significativas entre Serrano (n=21) con respecto a Centenario (n=14) (p=0,045) y a San Luis (n=16) (p=0,020), siendo la primera localidad mencionada quien mayor número de escolares con un consumo Muy Frecuente presentó; por último el grupo de salsas/aderezos fue consumido más de 4 veces/semana por una elevada proporción de escolares (65,2%), dónde Serrano (n=25) presentó mayor consumo en relación a Centenario (n=16) (p=0,014) y San Luis (n=22) (p=0,027). No se hallaron diferencias significativas respecto al análisis de estos productos según NSE. Por último, el principal entorno donde se consumieron los AUP fue el hogar y el mayor porcentaje (56,91%) lo hizo durante la merienda. Los resultados expuestos evidencian que los escolares residentes de localidades con menor grado de urbanización tuvieron mayor ingesta de AUP, sugiriendo que tanto la localidad de residencia como el contexto socioeconómico ejercen influencia sobre las elecciones y comportamientos alimentarios.

Role of the Arabidopsis PIN6 auxin transporter in auxin homeostasis and auxin-mediated development

Plant-specific PIN-formed (PIN) efflux transporters for the plant hormone auxin are required for tissue-specific directional auxin transport and cellular auxin homeostasis. The Arabidopsis PIN protein family has been shown to play important roles in developmental processes such as embryogenesis, organogenesis, vascular tissue differentiation, root meristem patterning and tropic growth. Here we analyzed roles of the less characterised Arabidopsis PIN6 auxin transporter. PIN6 is auxin-inducible and is expressed during multiple auxin–regulated developmental processes. Loss of pin6 function interfered with primary root growth and lateral root development. Misexpression of PIN6 affected auxin transport and interfered with auxin homeostasis in other growth processes such as shoot apical dominance, lateral root primordia development, adventitious root formation, root hair outgrowth and root waving. These changes in auxin-regulated growth correlated with a reduction in total auxin transport as well as with an altered activity of DR5-GUS auxin response reporter. Overall, the data indicate that PIN6 regulates auxin homeostasis during plant development.Christopher I. Cazzonelli, Marleen Vanstraelen, Sibu Simon, Kuide Yin, Ashley Carron-Arthur, Nazia Nisar, Gauri Tarle, Abby J. Cuttriss¤, Iain R. Searle, Eva Benkova, Ulrike Mathesius, Josette Masle, Jiří Friml, Barry J. Pogso

Stimulating technological innovation through incentives: Perceptions of Australian and Brazilian firms

Innovation has been the main driver of economic growth as it plays an increasingly central role in firm performance. Incentivising innovation by governments is essential to stimulate investment by companies, covering part of their R&amp;D costs, and minimising their financial risks. There is, however, limited understanding of how innovation incentives are perceived by the companies. This paper examines the perceptions of technology firms, and the views of key actors about public incentive schemes for innovation in Australia and Brazil. The study finds that: (a) Direct incentives are perceived as critical for increasing innovation capabilities of firms; (b) Where tax incentive and infrastructure development schemes are the most preferred incentive programs among the firms; (c) However, despite the former two findings, effectiveness of existing incentive programs has been marginal in fostering innovation significantly in the studied countries. These findings imply that Australian and Brazilian governments should further focus on the design, promotion, and delivery methods of the innovation support mechanisms.</p

Search for High-Mass Resonances Decaying to τν in pp Collisions at √s=13 TeV with the ATLAS Detector

A search for high-mass resonances decaying to τν using proton-proton collisions at √s=13 TeV produced by the Large Hadron Collider is presented. Only τ-lepton decays with hadrons in the final state are considered. The data were recorded with the ATLAS detector and correspond to an integrated luminosity of 36.1 fb−1. No statistically significant excess above the standard model expectation is observed; model-independent upper limits are set on the visible τν production cross section. Heavy W′ bosons with masses less than 3.7 TeV in the sequential standard model and masses less than 2.2–3.8 TeV depending on the coupling in the nonuniversal G(221) model are excluded at the 95% credibility level

Performance of missing transverse momentum reconstruction with the ATLAS detector using proton–proton collisions at √s = 13 TeV

The performance of the missing transverse momentum (EmissT) reconstruction with the ATLAS detector is evaluated using data collected in proton–proton collisions at the LHC at a centre-of-mass energy of 13 TeV in 2015. To reconstruct EmissT, fully calibrated electrons, muons, photons, hadronically decaying τ -leptons, and jets reconstructed from calorimeter energy deposits and charged-particle tracks are used. These are combined with the soft hadronic activity measured by reconstructed charged-particle tracks not associated with the hard objects. Possible double counting of contributions from reconstructed charged-particle tracks from the inner detector, energy deposits in the calorimeter, and reconstructed muons from the muon spectrometer is avoided by applying a signal ambiguity resolution procedure which rejects already used signals when combining the various EmissT contributions. The individual terms as well as the overall reconstructed EmissT are evaluated with various performance metrics for scale (linearity), resolution, and sensitivity to the data-taking conditions. The method developed to determine the systematic uncertainties of the EmissT scale and resolution is discussed. Results are shown based on the full 2015 data sample corresponding to an integrated luminosity of 3.2 fb−1

Operation and performance of the ATLAS Tile Calorimeter in Run 1

The Tile Calorimeter is the hadron calorimeter covering the central region of the ATLAS experiment at the Large Hadron Collider. Approximately 10,000 photomultipliers collect light from scintillating tiles acting as the active material sandwiched between slabs of steel absorber. This paper gives an overview of the calorimeter’s performance during the years 2008–2012 using cosmic-ray muon events and proton–proton collision data at centre-of-mass energies of 7 and 8TeV with a total integrated luminosity of nearly 30 fb−1. The signal reconstruction methods, calibration systems as well as the detector operation status are presented. The energy and time calibration methods performed excellently, resulting in good stability of the calorimeter response under varying conditions during the LHC Run 1. Finally, the Tile Calorimeter response to isolated muons and hadrons as well as to jets from proton–proton collisions is presented. The results demonstrate excellent performance in accord with specifications mentioned in the Technical Design Report

Measurement of the t¯tZ and t¯tW cross sections in proton-proton collisions at √s=13 TeV with the ATLAS detector

A measurement of the associated production of a top-quark pair (t¯t) with a vector boson (W, Z) in proton-proton collisions at a center-of-mass energy of 13 TeV is presented, using 36.1  fb−1 of integrated luminosity collected by the ATLAS detector at the Large Hadron Collider. Events are selected in channels with two same- or opposite-sign leptons (electrons or muons), three leptons or four leptons, and each channel is further divided into multiple regions to maximize the sensitivity of the measurement. The t¯tZ and t¯tW production cross sections are simultaneously measured using a combined fit to all regions. The best-fit values of the production cross sections are σt¯tZ=0.95±0.08stat±0.10syst pb and σt¯tW=0.87±0.13stat±0.14syst pb in agreement with the Standard Model predictions. The measurement of the t¯tZ cross section is used to set constraints on effective field theory operators which modify the t¯tZ vertex

Combined measurement of differential and total cross sections in the H → γγ and the H → ZZ* → 4ℓ decay channels at s=13 TeV with the ATLAS detector

A combined measurement of differential and inclusive total cross sections of Higgs boson production is performed using 36.1 fb−1 of 13 TeV proton–proton collision data produced by the LHC and recorded by the ATLAS detector in 2015 and 2016. Cross sections are obtained from measured H→γγ and H→ZZ*(→4ℓ event yields, which are combined taking into account detector efficiencies, resolution, acceptances and branching fractions. The total Higgs boson production cross section is measured to be 57.0−5.9 +6.0 (stat.) −3.3 +4.0 (syst.) pb, in agreement with the Standard Model prediction. Differential cross-section measurements are presented for the Higgs boson transverse momentum distribution, Higgs boson rapidity, number of jets produced together with the Higgs boson, and the transverse momentum of the leading jet. The results from the two decay channels are found to be compatible, and their combination agrees with the Standard Model predictions

Search for pairs of highly collimated photon-jets in pp collisions at √s = 13 TeV with the ATLAS detector

Results of a search for the pair production of photon-jets—collimated groupings of photons—in the ATLAS detector at the Large Hadron Collider are reported. Highly collimated photon-jets can arise from the decay of new, highly boosted particles that can decay to multiple photons collimated enough to be identified in the electromagnetic calorimeter as a single, photonlike energy cluster. Data from proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 36.7  fb−1, were collected in 2015 and 2016. Candidate photon-jet pair production events are selected from those containing two reconstructed photons using a set of identification criteria much less stringent than that typically used for the selection of photons, with additional criteria applied to provide improved sensitivity to photon-jets. Narrow excesses in the reconstructed diphoton mass spectra are searched for. The observed mass spectra are consistent with the Standard Model background expectation. The results are interpreted in the context of a model containing a new, high-mass scalar particle with narrow width, X, that decays into pairs of photon-jets via new, light particles, a. Upper limits are placed on the cross section times the product of branching ratios σ×B(X→aa)×B(a→γγ)2 for 200  GeV<mX<2  TeV and for ranges of ma from a lower mass of 100 MeV up to between 2 and 10 GeV, depending upon mX. Upper limits are also placed on σ×B(X→aa)×B(a→3π0)2 for the same range of mX and for ranges of ma from a lower mass of 500 MeV up to between 2 and 10 GeV