The scattering of solitons in classes of (1+1) dimensional models

We investigate the validity of the collective coordinate approximation to the scattering of two solitons in several classes of (1+1) dimensional field theory models. First we consider the collision of solitons in the integrable NLS model and compare the results of the collective coordinate approximation with results obtained using a full numerical simulation. We find that the approximation is accurate when the solitons are some distance apart and is reasonably good during their interaction. We then consider a modification of the NLS model with a deformation parameter which changes the integrability properties of the model, either completely or partially (the model becomes quasi-integrable). As the collective coordinate approximation does not allow for the radiation of energy out of a system we pay particular attention to how the approximation fares when the model is quasi-integrable and therefore has asymptotically conserved charges (i.e. charges Q(t) for which Q(t -> -infinity)=Q(t -> infinity)). We find that the approximation accurately reproduces the physical properties of the solitons, and even their anomalous charges, for a large range of initial values. The only time the approximation is not totally reliable is for the scatterings when the solitons come very close together (within one width of each other). To determine whether these results hold in a model with topological solitons we then consider a modified sine-Gordon model. The deformation preserves the topology of the model but changes the integrability properties in a similar way to the modified NLS model. In this model we find that the approximation is accurate when the model is either integrable or quasi-integrable, but the accuracy was much reduced when the model was completely non-integrable. To further explore this link between the accuracy of the collective coordinate approximation in a modified sine-Gordon model and the integrability properties of the system, we then consider soliton scattering in a double sine-Gordon model. The double sine-Gordon model allows us to vary between two integrable sine-Gordon models, and when the model is not integrable it still possesses the additional symmetries necessary for quasi-integrability. We find that for all values of our deformation parameters the approximation is accurate and that, as expected, the anomalous charges are asymptotically conserved

An evaluation of professional networks, co-ordination, cooperation and collaboration in the West Midlands Paediatric Palliative Care Network

Introduction: This is a report on Strand 3 of the Big Study, which studied the West Midlands Paediatric Palliative Care Network. The Big Study was funded by The Big Lottery Fund and Strand 3 of the Big Study was researched by the Centre for Nursing and Healthcare Research in the School of Health and Social Care at the University of Greenwich. 1.1 Background: The West Midlands Paediatric Palliative Care Network began as an interest group which started in the year 2000, with 6 to 10 members and grew. At one stage it was allied to the Birmingham Cancer Network and funded by the NHS Strategic Health Authority and at this stage it became more representative of services and West Midlands geography. It has existed in its current format, as a voluntary clinical network to promote paediatric palliative care and share best practice since 2009. The membership is wide and inclusive which means 30 to 40 people may attend the meetings which are held on a bimonthly basis and are hosted and supported charitably. Subgroups are now used to manage work in specific areas e.g. transition or clinical standards. There are links to other related networks with reciprocal membership and informal links to NHS commissioners who may seek advice. 1.2 Scope: This strand of the Big Study focused on the West Midlands Paediatric Palliative Care Network. The geographical area of the West Midlands Paediatric Palliative Care Network includes Birmingham, Coventry, The Black Country, Herefordshire, Shropshire, Solihull, Staffordshire, Stoke-on-Trent, Telford and Wrekin, Warwickshire and Worcestershire. All members of the WMPCCN and the organisations they represent were included in the study. Both NHS and non-NHS organisations offering clinical services to any children requiring palliative care were represented. Excluded from this study was the detailed examination of any of the other networks, e.g. children’s speciality networks or networks covering smaller geographical areas, to which members belonged. 1.3 Report: This report will present the results of an analysis of the responses to an online questionnaire and Social Network data from semi structured telephone interviews. This data was collected during the period February to June 2012. The approach included analysing the online survey data in order to understand the benefits and constraints of the network for individual members and Social Network Analysis of data derived from telephone interviews to explore the flow of knowledge, communication and information within the network. This report will consist of 3 different sections, with Section 1 focusing on children’s palliative care policy, the development of clinical networks and social network analysis concepts. Section 2 will focus on the research design and methods. Section 3 presents the results of the study and the final section provides a summary and conclusions of the analysis

Política migratoria del Reino Unido: restricciones sobre el derecho a estudiar de los solicitantes de asilo

Los cambios en la legislación de inmigración en el Reino Unido han conducido a restricciones en el derecho a estudiar de muchos solicitantes de asilo

Echocardiographic predictors of first onset of atrial fibrillation in dogs with myxomatous mitral valve disease

n/

Review of global in situ data for lakes and reservoirs

Lakes and reservoirs are vital components of global water resources. Yet, the persistent lack of comprehensive data on their water storage over time is due to limited access to in situ measurements. This data is essential for accurate modelling of hydrological systems, simulation of current operations, and forecasting future water demand and use. In recent years, Earth observations (EO) have emerged as a promising solution to enhance our understanding of various environmental phenomena, including hydrological processes and water resource management. However, the full potential of EO is hindered by limitations in accessing and collecting data from remote and inaccessible regions. This report provides a comprehensive overview of the undertaken task, which aimed to identify and catalogue associated metadata and access requirements for various readily available in situ data sources related to water body levels and/or storage. In response to the increasing utilization of EO-derived water body data in hydrological research, the task also includes relevant portals and links designed to facilitate access to this specific data category. A total of 95 websites and data sources were initially investigated. However, 35 were classified as having 'no data' due to either providing only summary statistics of aggregated reservoir metrics, or having no reservoir data available at all. An additional 9 entries were recorded as having 'other data,' where water body-related information was available, but no actual water storage or levels data. A few portals also required log-in credentials to access data records. Furthermore, 10 satellite-derived data portals were documented. Future steps for this task could involve expanding the catalogue with input from the hydrological community, adding information about the time periods covered by lake records and extracting further details about individual lakes covered, along with links to other lake and reservoir databases. Additionally, efforts could be made to standardise the time-series data from these links into a common file format and centralise them in a repository, all while considering licensing agreements and best practices for data citation