A search for gamma rays above 0.5 TeV from the southern radio pulsar PSR1706-44

A search for TeV gamma -rays from the isolated pulsar PSR1706-44 using the ground-based atmospheric Cerenkov imaging technique has been carried out. Analysis of data taken during 1993 and 1994 from the University of Adelaide's 37 pixel Cerenkov imaging telescope, with special attention paid to the effects of sky-noise differences between ON and OFF source regions, yielded an upper limit to the steady TeV gamma -ray emission. The 3sigma upper limit for energies above 0.5 TeV is 7.0(+/-0.7)x 10(-11) photons cm(-2) s(-1), consistent with the previously reported detection above ~ 1 TeV for steady emission.G.P. Rowell, S.A. Dazeley, P.G. Edwards, J.R. Patterson, and G.J. Thornto

Timing analysis techniques at large core distances for multi-TeV gamma ray astronomy

We present an analysis technique that uses the timing information of Cherenkov images from extensive air showers (EAS). Our emphasis is on distant, or large core distance gamma-ray induced showers at multi-TeV energies. Specifically, combining pixel timing information with an improved direction reconstruction algorithm, leads to improvements in angular and core resolution as large as ~40% and ~30%, respectively, when compared with the same algorithm without the use of timing. Above 10 TeV, this results in an angular resolution approaching 0.05 degrees, together with a core resolution better than ~15 m. The off-axis post-cut gamma-ray acceptance is energy dependent and its full width at half maximum ranges from 4 degrees to 8 degrees. For shower directions that are up to ~6 degrees off-axis, the angular resolution achieved by using timing information is comparable, around 100 TeV, to the on-axis angular resolution. The telescope specifications and layout we describe here are geared towards energies above 10 TeV. However, the methods can in principle be applied to other energies, given suitable telescope parameters. The 5-telescope cell investigated in this study could initially pave the way for a larger array of sparsely spaced telescopes in an effort to push the collection area to >10 km2. These results highlight the potential of a `sparse array' approach in effectively opening up the energy range above 10 TeV.Comment: Published in Astroparticle Physic

The Divisive Power of Humour: Comedy, Taste and Symbolic Boundaries

Using British and Dutch interview data, this article demonstrates how people from different social classes draw strong symbolic boundaries on the basis of comedy taste. Eschewing the omnivorousness described in recent studies of cultural consumption, comedy audiences make negative aesthetic and moral judgements on the basis of comedy taste, and often make harsh judgements without the disclaimers, apologies and ambivalence so typical of ‘taste talk’ in contemporary culture. The article demonstrates how, in particular, Dutch and British middle class audiences use their comedy taste to communicate distinction and cultural superiority. We discuss several reasons why such processes of social distancing exist in comedy taste and not other cultural areas: the traditionally low status of comedy; the strong relation between humour and personhood; the continuity between comedy tastes and humour styles in everyday life; as well as the specific position of comedy in the British and Dutch cultural fields

MACiE: a database of enzyme reaction mechanisms.

SUMMARY: MACiE (mechanism, annotation and classification in enzymes) is a publicly available web-based database, held in CMLReact (an XML application), that aims to help our understanding of the evolution of enzyme catalytic mechanisms and also to create a classification system which reflects the actual chemical mechanism (catalytic steps) of an enzyme reaction, not only the overall reaction. AVAILABILITY: http://www-mitchell.ch.cam.ac.uk/macie/.EPSRC (G.L.H. and J.B.O.M.), the BBSRC (G.J.B. and J.M.T.—CASE studentship in association with Roche Products Ltd; N.M.O.B. and J.B.O.M.—grant BB/C51320X/1), the Chilean Government’s Ministerio de Planificacio´n y Cooperacio´n and Cambridge Overseas Trust (D.E.A.) for funding and Unilever for supporting the Centre for Molecular Science Informatics.application note restricted to 2 printed pages web site: http://www-mitchell.ch.cam.ac.uk/macie

Simulating Fully‐Integrated Hydrological Dynamics in Complex Alpine Headwaters: Potential and Challenges

Highly simplified approaches continue to underpin hydrological climate change impact assessments across the Earth's mountainous regions. Fully-integrated surface-subsurface models may hold far greater potential to represent the distinctive regimes of steep, geologically-complex headwater catchments. However, their utility has not yet been tested across a wide range of mountainous settings. Here, an integrated model of two adjacent calcareous Alpine headwaters that accounts for two-dimensional surface flow, three-dimensional (3D) variably-saturated groundwater flow, and evapotranspiration is presented. An energy balance-based representation of snow dynamics contributed to the model's high-resolution forcing data, and a sophisticated 3D geological model helped to define and parameterize its subsurface structure. In the first known attempt to calibrate a catchment-scale integrated model of a mountainous region automatically, numerous uncertain model parameters were estimated. The salient features of the hydrological regime could ultimately be satisfactorily reproduced – over an 11-month evaluation period, the Nash-Sutcliffe efficiency of simulated streamflow at the main gauging station was 0.76. Spatio-temporal visualization of the forcing data and simulated responses further confirmed the model's broad coherence. Presumably due to unresolved local subsurface heterogeneity, closely replicating the somewhat contrasting groundwater level signals observed near to one another proved more elusive. Finally, we assessed the impacts of various simplifications and assumptions that are commonly employed in physically-based modeling – including the use of spatially uniform forcings, a vertically limited model domain, and global geological data products – on key simulated outputs, finding strongly affected model performance in many cases. Although certain outstanding challenges must be overcome if the uptake of integrated models in mountain regions around the world is to increase, our work demonstrates the feasibility and benefits of their application in such complex systems

Shear strength properties of wet granular materials

We investigate shear strength properties of wet granular materials in the pendular state (i.e. the state where the liquid phase is discontinuous) as a function of water content. Sand and glass beads were wetted and tested in a direct shear cell and under various confining pressures. In parallel, we carried out three-dimensional molecular dynamics simulations by using an explicit equation expressing capillary force as a function of interparticle distance, water bridge volume and surface tension. We show that, due to the peculiar features of capillary interactions, the major influence of water content over the shear strength stems from the distribution of liquid bonds. This property results in shear strength saturation as a function of water content. We arrive at the same conclusion by a microscopic analysis of the shear strength. We propose a model that accounts for the capillary force, the granular texture and particle size polydispersity. We find fairly good agreement of the theoretical estimate of the shear strength with both experimental data and simulations. From numerical data, we analyze the connectivity and anisotropy of different classes of liquid bonds according to the sign and level of the normal force as well as the bond direction. We find that weak compressive bonds are almost isotropically distributed whereas strong compressive and tensile bonds have a pronounced anisotropy. The probability distribution function of normal forces is exponentially decreasing for strong compressive bonds, a decreasing power-law function over nearly one decade for weak compressive bonds and an increasing linear function in the range of tensile bonds. These features suggest that different bond classes do not play the same role with respect to the shear strength.Comment: 12 page

A 3D geological model of a structurally complex Alpine region as a basis for interdisciplinary research

Dataset representing a 3D geological reconstruction of the a section of the Nappe de Morlces, Switzerland. Associated with "A 3D geological model of a structurally complex Alpine region as a basis for interdisciplinary research" (Thornton et al.

Sustaining the Digital Humanities in the UK

The Sustaining Digital Humanities in the UK report is timely for the UK Digital Humanities (DH) landscape. The establishment of UK Research and Innovation (UKRI) has created an opportune moment for the strategic planning of research infrastructure between and across all the research areas. Led by Giles Bergel and Pip Willcox, this report is based on the findings of a workshop held at the University of Oxford’s e-Research Centre (OeRC) on 21 June 2018 and sponsored by the Software Sustainability Institute. The workshop was led by an advisory board of Digital Humanities practitioners, representing a range of career stages, roles, and disciplines. The workshop’s organisers and advisory board are the joint authors of this report, with contributions from workshop participants. The mission of the Software Sustainability Institute (SSI) is to cultivate better, more sustainable, research software to enable world-class research. Currently celebrating its 10th year, the SSI has achieved broadening engagement across academic communities including humanities – for example as a longstanding supporter of the Digital Humanities at Oxford Summer School (DHOxSS), and with SSI Fellows in the arts and humanities areas. This report was commissioned by the SSI with the aim of advancing its mission within the humanities. Digital Humanities, a broad intersection of models, methods, tools, materials, career paths and affiliations, in both established and novel disciplines was identified as the area within the humanities that most closely aligns with the SSI’s role