Gillyweed – Drowning with Gills?

In David Yates’ film adaptation of J. K. Rowling’s Harry Potter and the Goblet of Fire, Harry Potter passes the second Triwizard task by consuming Gillyweed. This Mediterranean plant allows him to breathe underwater by growing gills on his neck. The gills were approximated to be 60 cm2 in surface area, and using standard measurements for a boy of his age, Harry was estimated to need to process 443 litres of water per minute. This came to mean the water would have to flow at 2.46 m s-1 across his gills, far faster than he could inhale and exhale

Are the Hometrees in James Cameron’s Avatar Structurally Possible?

In James Cameron’s Avatar, the Hometree is a sacred home for the Na’vi clans. These “trees” are said to be made of several thinner trees which have grown together to form a larger structure, suitable for its inhabitants. On Earth, the largest trees are significantly smaller (by almost a third). This paper concludes that factors such as reduced gravity result in only 22,100 N m-2­ of compression, low enough to allow the tree to stand.

Did Mark Watney make it Home from Mars?

At the conclusion of the 2015 film ‘The Martian’ astronaut Mark Watney cuts a hole in his space suit, and uses the escaping air as a mini thruster in order to make it to his rescuers. This paper finds that the air would not provide enough force to propel Watney with enough acceleration to make it home

Measurements of the Young’s modulus of hydroxide catalysis bonds, and the effect on thermal noise in ground-based gravitational wave detectors

With the outstanding results from the detection and observation of gravitational waves from coalescing black holes and neutron star inspirals, it is essential that pathways to further improve the sensitivities of the LIGO and VIRGO detectors are explored. There are a number of factors that potentially limit the sensitivities of the detectors. One such factor is thermal noise, a component of which results from the mechanical loss in the bond material between the silica fibre suspensions and the test mass mirrors. To calculate its magnitude, the Young’s modulus of the bond material has to be known with reasonable accuracy. In this paper we present a new combination of ultrasonic technology and Bayesian analysis to measure the Young’s modulus of hydroxide catalysis bonds between fused silica substrates. Using this novel technique, we measure the bond Young’s modulus to be 18.5 ± 2.0 2.3     GPa . We show that by applying this value to thermal noise models of bonded test masses with suitable attachment geometries, a reduction in suspension thermal noise consistent with an overall design sensitivity improvement allows a factor of 5 increase in event rate to be achieved

Identifying robust response options to manage environmental change using an ecosystem approach:a stress-testing case study for the UK

A diverse range of response options was evaluated in terms of their utility for sustaining ecosystem services in the UK. Robustness of response options was investigated by applying a ‘stress-testing’ method which evaluated expected performance against combined scenarios of socioeconomic and climate change. Based upon stakeholder feedback, a reference scenario representing current trends in climate and socioeconomic drivers (‘business-as-usual’) was used as a dynamic baseline against which to compare results of other scenarios. The robustness of response options was evaluated by their utility in different environmental and social contexts as represented by the scenarios, and linked to their adaptability to adjust to changing conditions. Key findings demonstrate that adaptability becomes increasingly valuable as the magnitude and rate of future change diverges from current trends. Stress-testing also revealed that individual responses in isolation are unlikely to be robust meaning there are advantages from integrating cohesive combinations (bundles) of response options to maximise their individual strengths and compensate for weaknesses. This identifies a role for both top-down and bottom-up responses, including regulation, spatial targeting, incentives and partnership initiatives, and their use in combination through integrated assessment and planning consistent with the adoption of an Ecosystem Approach. Stress-testing approaches can have an important role in future-proofing policy appraisals but important knowledge gaps remain, especially for cultural and supporting ecosystem services. Finally, barriers and enablers to the implementation of more integrated long-term adaptive responses were identified drawing on the ‘4 Is’ (Institutions, Information, Incentives, Identity) conceptual framework. This highlighted the crucial but usually understated role of identity in promoting ownership and uptake of responses

Submillimetre surveys: The prospects for Herschel

Using the observed submillimetre source counts, from 250-1200 microns (including the most recent 250, 350 and 500 micron counts from BLAST), we present a model capable of reproducing these results, which is used as a basis to make predictions for upcoming surveys with the SPIRE instrument aboard the Herschel Space Observatory. The model successfully fits both the integral and differential source counts of submillimetre galaxies in all wavebands, predicting that while ultra-luminous infrared galaxies dominate at the brightest flux densities, the bulk of the infrared background is due to the less luminous infrared galaxy population. The model also predicts confusion limits and contributions to the cosmic infrared background that are consistent with the BLAST results. Applying this to SPIRE gives predicted source confusion limits of 19.4, 20.5 and 16.1mJy in the 250, 350 and 500 micron bands respectively. This means the SPIRE surveys should achieve sensitivities 1.5 times deeper than BLAST, revealing a fainter population of infrared-luminous galaxies, and detecting approximately 2600, 1300, and 700 sources per square degree in the SPIRE bands (with one in three sources expected to be a high redshift ultra-luminous source at 500 microns). The model number redshift distributions predict a bimodal distribution of local quiescent galaxies and a high redshift peak corresponding to strongly evolving star-forming galaxies. It suggests the very deepest surveys with Herschel-SPIRE ought to sample the source population responsible for the bulk of the infrared background.Comment: 5 pages, 4 figures, accepted for publication in MNRAS Letter

Making change last: applying the NHSIII sustainability model to healthcare improvement

The implementation of evidence-based treatments to deliver high-quality care is essential to meet the healthcare demands of aging populations. However, the sustainable application of recommended practice is difficult to achieve and variable outcomes well recognised. The NHS Institute for Innovation and Improvement Sustainability Model (SM) was designed to help healthcare teams recognise determinants of sustainability and take action to embed new practice in routine care. This article describes a formative evaluation of the application of the SM by the National Institute for Health Research Collaboration for Leadership in Applied Health Research and Care for Northwest London (CLAHRC NWL). Data from project teams’ responses to the SM and formal reviews was used to assess acceptability of the SM and the extent to which it prompted teams to take action. Projects were classified as ‘engaged,’ ‘partially engaged’ and ‘non-engaged.’ Quarterly survey feedback data was used to explore reasons for variation in engagement. Score patterns were compared against formal review data and a ‘diversity of opinion’ measure was derived to assess response variance over time. Of the 19 teams, six were categorized as ‘engaged,’ six ‘partially engaged,’ and seven as ‘non-engaged.’ Twelve teams found the model acceptable to some extent. Diversity of opinion reduced over time. A minority of teams used the SM consistently to take action to promote sustainability but for the majority SM use was sporadic. Feedback from some team members indicates difficulty in understanding and applying the model and negative views regarding its usefulness. The SM is an important attempt to enable teams to systematically consider determinants of sustainability, provide timely data to assess progress, and prompt action to create conditions for sustained practice. Tools such as these need to be tested in healthcare settings to assess strengths and weaknesses and findings disseminated to aid development. This study indicates the SM provides a potentially useful approach to measuring teams’ views on the likelihood of sustainability and prompting action. Securing engagement of teams with the SM was challenging and redesign of elements may need to be considered. Capacity building and facilitation appears necessary for teams to effectively deploy the SM

Geometrical analysis of the inland topography to assess the likely response of wave-dominated coastline to sea level: application to Great Britain

The need for quantitative assessments at a large spatial scale (103 km) and over time horizons of the order 101 to 102 years have been reinforced by the 2019 Special Report on the Ocean and Cryosphere in a Changing Climate, which concluded that adaptation to a sea-level rise will be needed no matter what emission scenario is followed. Here, we used a simple geometrical analysis of the backshore topography to assess the likely response of any wave-dominated coastline to a sea-level rise, and we applied it along the entire Great Britain (GB) coastline, which is ca. 17,820 km long. We illustrated how the backshore geometry can be linked to the shoreline response (rate of change and net response: erosion or accretion) to a sea-level rise by using a generalized shoreline Exner equation, which includes the effect of the backshore slope and differences in sediment fractions within the nearshore. To apply this to the whole of GB, we developed an automated delineation approach to extract the main geometrical attributes. Our analysis suggests that 71% of the coast of GB is best described as gentle coast, including estuarine coastline or open coasts where back-barrier beaches can form. The remaining 39% is best described as cliff-type coastlines, for which the majority (57%) of the backshore slope values are negative, suggesting that a non-equilibrium trajectory will most likely be followed as a response to a rise in sea level. For the remaining 43% of the cliffed coast, we have provided regional statistics showing where the potential sinks and sources of sediment are likely to be

Galaxy Colours in the AKARI Deep SEP Survey

We investigate the segregation of the extragalactic population via colour criteria to produce an efficient and inexpensive methodology to select specific source populations as a function of far-infrared flux. Combining galaxy evolution scenarios and a detailed spectral library of galaxies, we produce simulated catalogues incorporating segregation of the extragalactic population into component types (Normal, star-forming, AGN) via color cuts. As a practical application we apply our criteria to the deepest survey to be undertaken in the far-infrared with the AKARI (formerly ASTRO-F) satellite. Using the far-infrared wavebands of the Far-Infrared Surveyor (FIS, one of the focal-plane instruments on AKARI) we successfully segregate the normal, starburst and ULIRG populations. We also show that with additional MIR imaging from AKARI's Infrared Camera (IRC), significant contamination and/or degeneracy can be further decreased and show a particular example of the separation of cool normal galaxies and cold ULIRG sources. We conclude that our criteria provide an efficient means of selecting source populations (including rare luminous objects) and produce colour-segregated source counts without the requirement of time intensive ground-based follow up to differentiate between the general galaxy population.Comment: Accepted for publication in Advances in Space Research. COSPAR, Beijing, 2006, E1.6 Advances in FIR and Submillimeter Astrophysics. (13 pages, 2 colour figures