Near-field THz imaging and spectroscopy using a multiple subwavelength aperture modulator

We present a near-field, simultaneous multiple pixel subwavelength THz transmission imaging device based on a solid-state THz spatial modulator. Frequency-division multiplexing is used to acquire multiple pixels simultaneously. The modulator was used to acquire THz transmission images with resolution of λ/4 at 118 µm. The image acquisition speed is 16 times greater than that of a comparable single-aperture subwavelength imaging technique. Additionally, spectroscopic THz imaging with subwavelength spatial resolution can be accomplished with the modulator, and the technique is scalable to at least 100 simultaneous pixels

Analysis of Academy School Performance in the 2011 and 2012 GCSEs

The Local Government Association (LGA) commissioned NFER to undertake statistical analysis of school level GCSE data provided by the Department of Education and accessible from their website. The purpose of the analysis was to determine whether there was any differential progress between Key Stage 2 and Key Stage 4 that can be associated with schools status. This report highlights analysis undertaken on the 2011 and 2012 GCSE results with future analysis on the 2013 and 2014 results also planned. Additional analyses looking at changes over time were also carried out.Analysis at the school level used average attainment at Key Stage 2 as measure of prior attainment and as a way to control for schools having different pupil intakes. Pupil progress was measured between KS2 and average GCSE points score. Two measures of GCSE attainment were used, average total point score (capped) and the proportion of pupil achievbing 5+ A* to C grades. Other school level factors that may have been associated with a variation in pupil progress were also included within the models. These included the proportion of pupils on free school meals and the proportion of pupils with special educational needs, as well as geographical location.Key Findings:In 2011 and 2012 schools with academy status made, on average, more progress between KS2 and GCSE than non academy status schools.Peformance, and interpretation, altered when excluding equivalent qualifications.There was no long term change in performance associated with academy status

Laser ablation deposition of Ga₂S₃-La₂S₃ glass films

Gallium - lanthanum sulphide glasses (GLS) show wide range transparency and low non radiative relaxation rates for dopant ions such as Ho3+, Er3+ etc. They also show permanent photomodification of the refractive index under visible illumination. We report laser ablation deposition of these glasses and preliminary results on film stoichiometry and deposition rate as a function of excimer laser fluence. The sulphur to metal and Ga/La ratios are found to have marked fluence dependencies. The films show considerably more Urbach tail absorption than bulk material. A novel method has been developed for mapping the permanent photomodifled index

Aggregators and the News Industry: Charging for Access to Content

The Internet has drastically altered the nature of competition in the news industry. This article develops a model of price and quality competition between rms in the online news industry. In equilibrium, rms randomise in their pricing strategies and this generates the cross- sectional mixture of advertiser and subscription funded models we ob- serve. The model also plausibly explains why pricing strategies dier across content areas. Finally, an important part of my explanation is that aggregators, such as Google and Digg.com, allow consumers to search amongst articles and direct consumers towards high quality articles. The model's results have implications for the ongoing public debate about the eects of aggregators on the news industry; although aggregators may harm rms, consumers may benet