So many things can happen in one minute

So many things can happen in one minute : text, Brigita Ozolins, Leigh Hobba This title has an association with the University of Tasmania, this author being a member of University staff. Catalogue of an exhibition by Nathalie de Briey, 'Work in progress (so many things can happen in one minute), held at the Plimsoll Gallery, Tasmanian School of Art, 7-29 July, 2001

Spatial division multiplexing for optical data center networks

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A directly comparative two-gate case-control diagnostic accuracy study of the pure tone screen and HearCheck Screener tests for identifying hearing impairment in school children

This is the final version. Available on open access from BMJ Publishing Group via the DOI in this recordObjectives This study directly compared the accuracy of two audiometry-based tests for screening school children for hearing impairment: the currently used test, pure tone screen and a device newly applied to children, HearCheck Screener. Design Two-gate case–control diagnostic test accuracy study. Setting and participants Hearing impaired children (‘intended cases’) aged 4–6 years were recruited between February 2013 and August 2014 from collaborating audiology services. Children with no previously identified impairment (‘intended controls’) were recruited from Foundation and Year 1 of schools between February 2013 and June 2014 in central England. The reference standard was pure tone audiometry. Tests were administered at Nottingham Hearing Biomedical Research Unit or, for some intended cases only, in the participant’s home. Main outcome measures Sensitivity and specificity of the pure tone screen and HearCheck tests based on pure tone audiometry result as reference standard. Results 315 children (630 ears) were recruited; 75 from audiology services and 240 from schools. Full test and reference standard data were obtained for 600 ears; 155 ears were classified as truly impaired and 445 as truly hearing based on the pure tone audiometry assessment. Sensitivity was estimated to be 94.2% (95% CI 89.0% to 97.0%) for pure tone screen and 89.0% (95% CI 82.9% to 93.1%) for HearCheck (difference=5.2% favouring pure tone screen; 95% CI 0.2% to 10.1%; p=0.02). Estimates for specificity were 82.2% (95% CI 77.7% to 86.0%) for pure tone screen and 86.5% (95% CI 82.5% to 89.8%) for HearCheck (difference=4.3% favouring HearCheck; 95% CI0.4% to 8.2%; p=0.02). Conclusion Pure tone screen was better than HearCheck with respect to sensitivity but inferior with respect to specificity. As avoiding missed cases is arguably of greater importance for school entry screening, pure tone screen is probably preferable in this context.National Institute for Health Research (NIHR)University of ExeterNottingham University Hospitals National Health Service (NHS) TrustCCS NHS TrustAddenbrookes Hospital, Cambridge University Hospitals Foundation TrustUniversity of Nottingha

TuB4.1-chip based thz emitter for ultra-high speed THz wireless communication (Invited)

By using a monolithically integrated dualdistributed feedback (DFB) laser chip attached to a photomixing uni-travelling carrier photodiode (UTC-PD) with a THz antenna, a single-channel THz photonic-wireless transmission system with a net rate of 131 Gbit/s over a wireless distance of 10.7 m has been achieved

Wildlife population changes across eastern europe after the collapse of socialism

When political regimes fall, economic conditions change and wildlife protection can be undermined. Eastern European countries experienced turmoil following the collapse of socialism in the early 1990s, raising the question of how wildlife was affected. We show that the aftermath of the collapse changed the population growth rates of various wildlife taxa. We analyzed populations of moose (Alces alces), wild boar (Sus scrofa), red deer (Cervus elaphus), roe deer (Capreolus capreolus), brown bear (Ursus arctos), Eurasian lynx (Lynx lynx), and gray wolf (Canis lupus) in nine countries. Population growth rates changed in 32 out of 49 time series. In the countries that reformed slowly, many species exhibited rapid population declines, and population growth rates changed in 83% of the time series. In contrast, in countries with fast post- socialism reforms, many populations increased rapidly, and growth rates changed in only 48% of time series. Our results suggest that the direction and frequency of the changes were associated with socioeconomic conditions, and that wildlife populations can be greatly affected by socioeconomic upheavals

Use of the Generalized Gradient Approximation in Pseudopotential Calculations of Solids

We present a study of the equilibrium properties of $sp$-bonded solids within the pseudopotential approach, employing recently proposed generalized gradient approximation (GGA) exchange correlation functionals. We analyze the effects of the gradient corrections on the behavior of the pseudopotentials and discuss possible approaches for constructing pseudopotentials self-consistently in the context of gradient corrected functionals. The calculated equilibrium properties of solids using the GGA functionals are compared to the ones obtained through the local density approximation (LDA) and to experimental data. A significant improvement over the LDA results is achieved with the use of the GGA functionals for cohesive energies. For the lattice constant, the same accuracy as in LDA can be obtained when the nonlinear coupling between core and valence electrons introduced by the exchange correlation functionals is properly taken into account. However, GGA functionals give bulk moduli that are too small compared to experiment.Comment: 15 pages, latex, no figure