Electrophysiological and Behavioural Studies of Habituation

Responses to repetitive stimulation are found to decrease in frequency and amplitude over time. Similar habituation effects have been reported in evoked potentials recorded in the auditory pathway of cats, although some later studies have not confirmed these initial findings. The first set of experiments examined the relationship of auditory evoked potential habituation (AEPH) and stimulus variables known to determine behavioural response habituation (BRH). Decrements in evoked potentials to repetitive stimulation did not follow typical habituation functions. The second set of experiments tested various theories which have been put forward to explain the decrements. Explanations based on conditioning of the middle ear muscles were rejected and explanations based on either reticular formation inhibition or cortical inhibition were considerably weakened. The only theory supported was one explaining the decrements by inhibition intrinsic to the recording area. A third set of experiments supported predictions from this theory and some evidence indicated that the intrinsic inhibition could be postsynaptic inhibition at the level of the thalamus. nts examined the effect on auditory evoked potentials of an animal attending to a stimulus in another modality. It was found that previous reports of a decrement during attention were based on an artefact of movement. However, attentive effects were observed at the thalamus during the presentation of aversive stimuli. It was concluded that the sensory correlate of habituation might be based on a small number of specialised cells, whose function would not be detected by the evoked potential technique. It was also concluded that the evoked potential study of attentional mechanisms should concentrate on determining whether such effects were pre- or postsynaptic in nature

Atlantic Behavioral Response Study: Experimental Design, Analytical Methods, and Preliminary Results

Excerpted from ESOMM - 2018, 6th International Meeting on the Effects of Sound in the Ocean on Marine Mammals The Hague, The Netherlands

Safety vs. reputation: risk controversies in emerging policy networks regarding school safety in the Netherlands

This article deals with risk controversies in emerging policy networks regarding school safety in the Netherlands. It offers a grounded account of the interpretations of school risks and safety measures by the various stakeholders of the policy network, in particular, schools, local government and the police. Theoretically, policy networks are conceived as mediating between the structural conditions of the risk-society and the culture of fear on the one hand and the institution of safety standards on the organizational level of schools on the other hand. It is argued that in the low-risk context of schools, it is particularly important to take into account the soft, cultural side of safety next to the hard, material side of safety. This distinction also accounts for the ambiguities and controversies over school risks. A further conclusion is that in this network a lack of local leadership seems to hinder the development of firm safety measures. Overall, this article highlights the paradox between a concern for safety and a concern for a schools reputation. © 2012 Taylor & Francis

Desempenho produtivo de porta-enxertos de macieira da série Geneva em solo de replantio

The objective of this work was to identify rootstocks with competitive agronomic potential to substitute those currently used in Southern Brazil for the Galaxy and Fuji Suprema apple scion cultivars cultivated on replanting soils. The experiment was carried out in the municipality of Lebon Regis, in the state of Santa Catarina, Brazil, from the 2009/2010 to the 2014/2015 crop season, in a randomized complete block design, with four replicates. The yield performance of the 'Galaxy' and 'Fuji Suprema' scions grafted on the G.056, G.202, G.213, G.814, G.896, G.969, M.9, and Marubakaido/M.9 rootstocks was evaluated. G.896 and G.814 stood out due to their superior annual and cumulative fruit yields, as well as to their greater yield regularity, although they showed lower ability of dwarfing the scion. The greatest average fruit weight of 'Galaxy' was obtained on G.056 and G.213. For 'Fuji Suprema', G.969 promoted smaller fruits, whereas the other rootstocks did not differ. All the evaluated rootstocks produced less suckers than Marubakaido/M.9 and less burrknots than M.9 and Marubakaido/M.9. In general, on replanting soil conditions, G.202 is promising among dwarfing rootstocks, mainly for 'Fuji Suprema'. G.056, G.814, and G.896 also stand out, and the two first are more specific for 'Fuji Suprema'.O objetivo deste trabalho foi identificar porta-enxertos com potencial agronômico competitivo para substituir os tradicionalmente usados no Sul do Brasil para as cultivares-copa de macieira Galaxy e Fuji Suprema cultivadas em solo de replantio. O experimento foi conduzido em Lebon Regis, no Estado de Santa Catarina, nas safras de 2009/2010 a 2014/2015, em delineamento experimental de blocos ao acaso, com quatro repetições. Avaliou-se o desempenho agronômico das copas 'Galaxy' e 'Fuji Suprema', enxertadas sobre G.056, G.202, G.213, G.814, G.896, G.969, M.9 e Marubakaido/M.9. G.896 e G.814 se destacaram pelas produções de frutos anual e acumulada superiores, bem como pela maior regularidade produtiva, embora tenham apresentado menor capacidade ananizante sobre a copa. As maiores massas médias de frutos de 'Galaxy' foram obtidas sobre G.056 e G.213. Para 'Fuji Suprema', G.969 proporcionou frutos menores, enquanto os demais porta-enxertos não diferiram entre si. Todos os porta-enxertos avaliados rebrotaram menos que Marubakaido/M.9 e produziram menos “burrknots” que M.9 e Marubakaido/M.9. No geral, nas condições de solo de replantio, G.202 mostra ser promissor entre os porta-enxertos ananizantes, principalmente para 'Fuji Suprema'. Destacam-se também G.056, G.814 e G.896, sendo os dois primeiros mais específicos para 'Fuji Suprema'

Measurement of the cross section of high transverse momentum Z→bb̄ production in proton–proton collisions at √s = 8 TeV with the ATLAS detector

This Letter reports the observation of a high transverse momentum Z→bb̄ signal in proton–proton collisions at √s=8 TeV and the measurement of its production cross section. The data analysed were collected in 2012 with the ATLAS detector at the LHC and correspond to an integrated luminosity of 19.5 fb−¹. The Z→bb̄ decay is reconstructed from a pair of b -tagged jets, clustered with the anti-ktkt jet algorithm with R=0.4R=0.4, that have low angular separation and form a dijet with pT>200 GeVpT>200 GeV. The signal yield is extracted from a fit to the dijet invariant mass distribution, with the dominant, multi-jet background mass shape estimated by employing a fully data-driven technique that reduces the dependence of the analysis on simulation. The fiducial cross section is determined to be σZ→bb¯fid=2.02±0.20 (stat.) ±0.25 (syst.)±0.06 (lumi.) pb=2.02±0.33 pb, in good agreement with next-to-leading-order theoretical predictions

Measurement of the branching ratio Γ(Λb⁰ → ψ(2S)Λ0)/Γ(Λb⁰ → J/ψΛ0) with the ATLAS detector

An observation of the $\Lambda_b^0 \rightarrow \psi(2S) \Lambda^0$ decay and a comparison of its branching fraction with that of the $\Lambda_b^0 \rightarrow J/\psi \Lambda^0$ decay has been made with the ATLAS detector in proton--proton collisions at $\sqrt{s}=8\,$TeV at the LHC using an integrated luminosity of $20.6\,$fb$^{-1}$. The $J/\psi$ and $\psi(2S)$ mesons are reconstructed in their decays to a muon pair, while the $\Lambda^0\rightarrow p\pi^-$ decay is exploited for the $\Lambda^0$ baryon reconstruction. The $\Lambda_b^0$ baryons are reconstructed with transverse momentum $p_{\rm T}>10\,$GeV and pseudorapidity $|\eta|<2.1$. The measured branching ratio of the $\Lambda_b^0 \rightarrow \psi(2S) \Lambda^0$ and $\Lambda_b^0 \rightarrow J/\psi \Lambda^0$ decays is $\Gamma(\Lambda_b^0 \rightarrow \psi(2S)\Lambda^0)/\Gamma(\Lambda_b^0 \rightarrow J/\psi\Lambda^0) = 0.501\pm 0.033 ({\rm stat})\pm 0.019({\rm syst})$, lower than the expectation from the covariant quark model.Comment: 12 pages plus author list (28 pages total), 5 figures, 1 table, published on Physics Letters B 751 (2015) 63-80. All figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/BPHY-2013-08

Search for strong gravity in multijet final states produced in pp collisions at √s=13 TeV using the ATLAS detector at the LHC

A search is conducted for new physics in multijet final states using 3.6 inverse femtobarns of data from proton-proton collisions at √s = 13TeV taken at the CERN Large Hadron Collider with the ATLAS detector. Events are selected containing at least three jets with scalar sum of jet transverse momenta (HT) greater than 1TeV. No excess is seen at large HT and limits are presented on new physics: models which produce final states containing at least three jets and having cross sections larger than 1.6 fb with HT > 5.8 TeV are excluded. Limits are also given in terms of new physics models of strong gravity that hypothesize additional space-time dimensions

Operation and performance of the ATLAS semiconductor tracker

The semiconductor tracker is a silicon microstrip detector forming part of the inner tracking system of the ATLAS experiment at the LHC. The operation and performance of the semiconductor tracker during the first years of LHC running are described. More than 99% of the detector modules were operational during this period, with an average intrinsic hit efficiency of (99.74±0.04)%. The evolution of the noise occupancy is discussed, and measurements of the Lorentz angle, δ-ray production and energy loss presented. The alignment of the detector is found to be stable at the few-micron level over long periods of time. Radiation damage measurements, which include the evolution of detector leakage currents, are found to be consistent with predictions and are used in the verification of radiation background simulations