Investigation of the Nicole model

We study soliton solutions of the Nicole model - a non-linear four-dimensional field theory consisting of the CP^1 Lagrangian density to the non-integer power 3/2 - using an ansatz within toroidal coordinates, which is indicated by the conformal symmetry of the static equations of motion. We calculate the soliton energies numerically and find that they grow linearly with the topological charge (Hopf index). Further we prove this behaviour to hold exactly for the ansatz. On the other hand, for the full three-dimensional system without symmetry reduction we prove a sub-linear upper bound, analogously to the case of the Faddeev-Niemi model. It follows that symmetric solitons cannot be true minimizers of the energy for sufficiently large Hopf index, again in analogy to the Faddeev-Niemi model.Comment: Latex, 35 pages, 1 figur

Liquid drops on a surface: using density functional theory to calculate the binding potential and drop profiles and comparing with results from mesoscopic modelling

The contribution to the free energy for a film of liquid of thickness $h$ on a solid surface, due to the interactions between the solid-liquid and liquid-gas interfaces is given by the binding potential, $g(h)$. The precise form of $g(h)$ determines whether or not the liquid wets the surface. Note that differentiating $g(h)$ gives the Derjaguin or disjoining pressure. We develop a microscopic density functional theory (DFT) based method for calculating $g(h)$, allowing us to relate the form of $g(h)$ to the nature of the molecular interactions in the system. We present results based on using a simple lattice gas model, to demonstrate the procedure. In order to describe the static and dynamic behaviour of non-uniform liquid films and drops on surfaces, a mesoscopic free energy based on $g(h)$ is often used. We calculate such equilibrium film height profiles and also directly calculate using DFT the corresponding density profiles for liquid drops on surfaces. Comparing quantities such as the contact angle and also the shape of the drops, we find good agreement between the two methods. We also study in detail the effect on $g(h)$ of truncating the range of the dispersion forces, both those between the fluid molecules and those between the fluid and wall. We find that truncating can have a significant effect on $g(h)$ and the associated wetting behaviour of the fluid.Comment: 16 pages, 13 fig

Cybersecurity: mapping the ethical terrain

This edited collection examines the ethical trade-offs involved in cybersecurity: between security and privacy; individual rights and the good of a society; and between the types of burdens placed on particular groups in order to protect others. Foreword Governments and society are increasingly reliant on cyber systems. Yet the more reliant we are upon cyber systems, the more vulnerable we are to serious harm should these systems be attacked or used in an attack. This problem of reliance and vulnerability is driving a concern with securing cyberspace. For example, a ‘cybersecurity’ team now forms part of the US Secret Service. Its job is to respond to cyber-attacks in specific environments such as elevators in a building that hosts politically vulnerable individuals, for example, state representatives. Cybersecurity aims to protect cyberinfrastructure from cyber-attacks; the concerning aspect of the threat from cyber-attack is the potential for serious harm that damage to cyber-infrastructure presents to resources and people. These types of threats to cybersecurity might simply target information and communication systems: a distributed denial of service (DDoS) attack on a government website does not harm a website in any direct way, but prevents its normal use by stifling the ability of users to connect to the site. Alternatively, cyber-attacks might disrupt physical devices or resources, such as the Stuxnet virus, which caused the malfunction and destruction of Iranian nuclear centrifuges. Cyber-attacks might also enhance activities that are enabled through cyberspace, such as the use of online media by extremists to recruit members and promote radicalisation. Cyber-attacks are diverse: as a result, cybersecurity requires a comparable diversity of approaches. Cyber-attacks can have powerful impacts on people’s lives, and so—in liberal democratic societies at least—governments have a duty to ensure cybersecurity in order to protect the inhabitants within their own jurisdiction and, arguably, the people of other nations. But, as recent events following the revelations of Edward Snowden have demonstrated, there is a risk that the governmental pursuit of cybersecurity might overstep the mark and subvert fundamental privacy rights. Popular comment on these episodes advocates transparency of government processes, yet given that cybersecurity risks represent major challenges to national security, it is unlikely that simple transparency will suffice. Managing the risks of cybersecurity involves trade-offs: between security and privacy; individual rights and the good of a society; and types of burdens placed on particular groups in order to protect others. These trade-offs are often ethical trade-offs, involving questions of how we act, what values we should aim to promote, and what means of anticipating and responding to the risks are reasonably—and publicly—justifiable. This Occasional Paper (prepared for the National Security College) provides a brief conceptual analysis of cybersecurity, demonstrates the relevance of ethics to cybersecurity and outlines various ways in which to approach ethical decision-making when responding to cyber-attacks

The physician’s role in perioperative management of older patients undergoing surgery

Life-sustaining and life-improving surgical interventions are increasingly available to older, frailer patients, many of whom have multimorbidity. Physicians can help support perioperative multidisciplinary teams with assessment and preoperative optimisation of physiological reserve, comorbidities and associated geriatric syndromes. Similar structured support can be useful in the postoperative period where older patients are at increased risk of delirium, medical complications, increased functional dependency and where discharge planning can prove more difficult than in younger cohorts. Comprehensive geriatric assessment has been shown to improve outcomes and is now embedded in most UK-based services for traumatic hip fracture. Perioperative comprehensive geriatric assessment has been explored in other surgical disciplines and procedures and, where evaluated, has been associated with improved outcomes. The need to support older patients with frailty undergoing surgery exceeds the capacity of specialist geriatricians. Other groups of healthcare professionals need to nurture the core competencies to support this group perioperatively

Intraoperative Neurophysiological Monitoring for Endoscopic Endonasal Approaches to the Skull Base: A Technical Guide.

Intraoperative neurophysiological monitoring during endoscopic, endonasal approaches to the skull base is both feasible and safe. Numerous reports have recently emerged from the literature evaluating the efficacy of different neuromonitoring tests during endonasal procedures, making them relatively well-studied. The authors report on a comprehensive, multimodality approach to monitoring the functional integrity of at risk nervous system structures, including the cerebral cortex, brainstem, cranial nerves, corticospinal tract, corticobulbar tract, and the thalamocortical somatosensory system during endonasal surgery of the skull base. The modalities employed include electroencephalography, somatosensory evoked potentials, free-running and electrically triggered electromyography, transcranial electric motor evoked potentials, and auditory evoked potentials. Methodological considerations as well as benefits and limitations are discussed. The authors argue that, while individual modalities have their limitations, multimodality neuromonitoring provides a real-time, comprehensive assessment of nervous system function and allows for safer, more aggressive management of skull base tumors via the endonasal route

Non-disabled secondary school children’s lived experiences of a wheelchair basketball programme delivered in the East of England

Frequently an unquestioned belief is held in UK schools in the value of ‘normalised’ ability in physical education. Consequently inclusion of disabled students can be problematical. Negative perceptions of disability are rarely challenged. This study investigated the embodied experiences of 50 non-disabled secondary school pupils during a programme designed to introduce disability sport to non-disabled schoolchildren entitled ‘The Wheelchair Sports Project.’ Wheelchair Basketball sessions were delivered by coaches during physical education for a 12 week period. 50 pupils aged between 10 and 12 years took part. Non-participant observations were completed during the intervention and guided group interviews were completed with 40 participants pre and post project. Bourdieu’s theoretical framework was utilized during data analysis. The impact of the project on pupils’ perceptions of physical disability was investigated. Prior to the project, pupils emphasized the ‘otherness’ of disabled bodies and described disability sport as inferior and not ‘real.’ Observations highlighted how pupils’ experienced physical challenges adapting to wheelchair basketball. Pupils struggled to control wheelchairs and frequently diverged from acceptable behaviour by using their lower limbs to ‘cheat.’ Post-programme interviews demonstrated pupils’ perceptions of physical disability altered due to their embodied experiences. Pupils described high physical demands of wheelchair basketball and began to focus upon similarities between themselves and physically disabled individuals. However, no reference was made to mental or psychological disability, emphasizing the specificity of the effects of pupils’ embodied experiences on their habitus’

Arm-length stabilisation for interferometric gravitational-wave detectors using frequency-doubled auxiliary lasers

Residual motion of the arm cavity mirrors is expected to prove one of the principal impediments to systematic lock acquisition in advanced gravitational-wave interferometers. We present a technique which overcomes this problem by employing auxiliary lasers at twice the fundamental measurement frequency to pre-stabilise the arm cavities' lengths. Applying this approach, we reduce the apparent length noise of a 1.3 m long, independently suspended Fabry-Perot cavity to 30 pm rms and successfully transfer longitudinal control of the system from the auxiliary laser to the measurement laser

An ethnographic study of career aspirations amongst students studying level 3 sports courses at a further education college in England

There is currently a dearth of research into how sports students’ career aspirations are formed during their post-compulsory education. This paper is based on an ethnographic study of sport students’ habitus and career aspirations. Two first-year cohorts on two different courses at a Further Education College in England were selected to participate in the in-depth study. The paper provides an analysis of the contrasting subcultures emergent within these groups, and how specific cultural practices affect students’ career aspirations vis-à-vis the current global recession and economic crisis. Utilising a Bourdieusian framework, the study is based upon formal and informal (auto)ethnographic observations and semi-structured group interviews, and aims to unearth the internalised, often latent cultural practices that impact upon these students’ diverse career aspirations in the field of further education in sport. The paper reveals how the two cohorts are situated within a complex field of relations; where struggles for legitimisation, kudos, academic accomplishment and numerous forms of lucrative capital are habituated. Despite the two courses being of equivalent academic level, the scholastic and career aspirations of the two groups appear to differ considerably. One cohort is eager to demonstrate aspirations of progression into Higher Education, whereas the other cohort appears content with achieving the lowest grades “required” to pursue full-time employment. The study will offer academics and practitioners valuable insights into both the career aspirations of these students, and also their attitudes towards their educational field and their contrasting work ethics

The Bolocam Galactic Plane Survey. XI. Temperatures and Substructure of Galactic Clumps Based on 350 ?M Observations

We present 107 maps of continuum emission at 350 mu m from Galactic molecular clumps. Observed sources were mainly selected from the Bolocam Galactic Plane Survey (BGPS) catalog, with three additional maps covering star-forming regions in the outer Galaxy. The higher resolution of the SHARC-II images (8."5 beam) compared with the 1.1 mm images from BGPS (33"beam) allowed us to identify a large population of smaller substructures within the clumps. A catalog is presented for the 1386 sources extracted from the 350 mu m maps. The color temperature distribution of clumps based on the two wavelengths has a median of 13.3 K and mean of 16.3 +/- 0.4 K, assuming an opacity law index of 1.7. For the structures with good determination of color temperatures, the mean ratio of gas temperature, determined from NH3 observations, to dust color temperature is 0.88 and the median ratio is 0.76. About half the clumps have more than 2 substructures and 22 clumps have more than 10. The fraction of the mass in dense substructures seen at 350 mu m compared to the mass of their parental clump is similar to 0.19, and the surface densities of these substructures are, on average, 2.2 times those seen in the clumps identified at 1.1 mm. For a well-characterized sample, 88 structures (31%) exceed a surface density of 0.2 g cm(-2), and 18 (6%) exceed 1.0 g cm(-2), thresholds for massive star Formation suggested by theorists.National Science Foundation through NSF grant AST-0708403NRAONSF AST-9980846, AST-0206158, AST-1109116Fulbright FellowshipASI, AgenziaSpaziale Italiana I/038/080/0, I/029/12/0national funding agency: CSA (Canada)national funding agency: NAOC (China)national funding agency: CEA (France)national funding agency: ASI (Italy)national funding agency: MCINN (Spain)national funding agency: Stockholm Observatory (Sweden)national funding agency: STFC (UK)national funding agency: NASA (USA)national funding agency: CNES (France)national funding agency: CNRS (France)Astronom