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An examination of why educational technology has progressed so slowly and remained on the periphery of educational systems." The article also outlines some of the requirements necessary for educational technology to succeed. (Author/AA)

The author discusses a number of current trends which seem likely to shape future developments" in education. (Author/AK)

A critical review of the claims made on behalf of the expansion of cable television by its proponents, which places this medium in the context of past media and the as yet unjustified claims made for them. (JM)

Background Idiopathic macular holes are an important cause of blindness. They have an annual incidence of 8 per 100,000 individuals, and prevalence of 0.2 to 3.3 per 1000 individuals with visual impairment. The condition occurs more frequently in adults aged 75 years or older. Macular holes can be repaired by surgery in which the causative tractional forces in the eye are released and a temporary bubble of gas is injected. To promote successful hole closure individuals may be advised to maintain a face-down position for up to 10 days following surgery. The aim of this study is to determine whether advice to position face-down improves the surgical success rate of closure of large (>400 μm) macular holes, and thereby reduces the need for further surgery. Methods/Design This will be a multicentre interventional, comparative randomised controlled clinical trial comparing face-down positioning with face-forward positioning. At the conclusion of standardised surgery across all sites, participants still eligible for inclusion will be allocated randomly 1:1 to 1 of the 2 treatment arms stratified by site, using random permuted blocks of size 4 or 6 in equal proportions. We will recruit 192 participants having surgery for large macular holes (>400 μm); 96 in each of the 2 arms of the study. The primary objective is to determine the impact of face-down positioning on the likelihood of closure of large (≥400 μm) full-thickness macular holes following surgery. Discussion This will be the first multicentre randomised control trial to investigate the value of face-down positioning following macular hole standardised surgery. Trial registration UK CRN: 17966 (date of registration 26 November 2014). Electronic supplementary material The online version of this article (doi:10.1186/s13063-015-1048-8) contains supplementary material, which is available to authorized users.

Examples of face-forward reading and face-forward watching TV. (DOCX 414 kb)

Consent form. (DOCX 38 kb)

Flow diagram of PIMS trial. (DOCX 39 kb)

OCT image of macular hole.(DOCX 627 kb)

Examples of face-down seated and face-down lying. (DOCX 446 kb)

Fluid circulation in the Earth's crust plays an essential role in surface, near surface, and deep crustal processes. Flow pathways are driven by hydraulic gradients but controlled by material permeability, which varies over many orders of magnitude and changes over time. Although millions of measurements of crustal properties have been made, including geophysical imaging and borehole tests, this vast amount of data and information has not been integrated into a comprehensive knowledge system. A community data infrastructure is needed to improve data access, enable large‐scale synthetic analyses, and support representations of the subsurface in Earth system models. Here, we describe the motivation, vision, challenges, and an action plan for a community‐governed, four‐dimensional data system of the Earth's crustal structure, composition, and material properties from the surface down to the brittle–ductile transition. Such a system must not only be sufficiently flexible to support inquiries in many different domains of Earth science, but it must also be focused on characterizing the physical crustal properties of permeability and porosity, which have not yet been synthesized at a large scale. The DigitalCrust is envisioned as an interactive virtual exploration laboratory where models can be calibrated with empirical data and alternative hypotheses can be tested at a range of spatial scales. It must also support a community process for compiling and harmonizing models into regional syntheses of crustal properties. Sustained peer review from multiple disciplines will allow constant refinement in the ability of the system to inform science questions and societal challenges and to function as a dynamic library of our knowledge of Earth's crust.

HydroShare poster presented at SI2 PI meeting in Arlington, Virginia, February 24, 2014

I present a new Stata command, simsam, that uses simulation to determine the sample size required to achieve a given statistical power for any hypothesis test under any probability model that can be programmed in Stata. simsam returns the smallest sample size (or smallest multiple of 5, 10, or some other user-specified increment) so that the estimated power exceeds the target. The user controls the precision of the power estimate, and power is reported with a confidence interval. The sample size returned is reliable to the extent that if simsam is repeated, it will, nearly every time, give a sample size no more than one increment away.

The EarthCube goal of creating an infrastructure for managing and integrating knowledge across all geosciences in an open, transparent and inclusive manner aligns well with the overarching goals for the work that has been done in CUAHSI on Hydrologic Information Systems. CUAHSI has taken some steps in this direction, but a lot remains to be done. This paper describes these steps and makes some suggestions for the path ahead.