Bi-algebras, generalised geometry and T-duality

A study of sigma models whose target space is a group G that admits a compatible Poisson structure is presented. The natural action of O(D,D;Z) on the generalised tangent bundle TG+T*G and a generalisation of the Courant bracket that appears are reviewed. This background provides a concrete example where the generalised geometry and doubled geometry descriptions are both well understood. Connections between the two formalisms are discussed and the world-sheet theory from Hamiltonian and Lagrangian perspectives is investigated. The comparisons between the approaches given by generalised geometry and doubled geometry suggest possible ways of generalising the analysis beyond the known examples.Comment: 43 page

Multislice Modularity Optimization in Community Detection and Image Segmentation

Because networks can be used to represent many complex systems, they have attracted considerable attention in physics, computer science, sociology, and many other disciplines. One of the most important areas of network science is the algorithmic detection of cohesive groups (i.e., "communities") of nodes. In this paper, we algorithmically detect communities in social networks and image data by optimizing multislice modularity. A key advantage of modularity optimization is that it does not require prior knowledge of the number or sizes of communities, and it is capable of finding network partitions that are composed of communities of different sizes. By optimizing multislice modularity and subsequently calculating diagnostics on the resulting network partitions, it is thereby possible to obtain information about network structure across multiple system scales. We illustrate this method on data from both social networks and images, and we find that optimization of multislice modularity performs well on these two tasks without the need for extensive problem-specific adaptation. However, improving the computational speed of this method remains a challenging open problem.Comment: 3 pages, 2 figures, to appear in IEEE International Conference on Data Mining PhD forum conference proceeding

Aspects of unconventional density waves

Recently many people discuss unconventional density waves (i.e. unconventional charge density waves (UCDW) and unconventional spin density waves (USDW)). Unlike in conventional density waves, the quasiparticle spectrum in these systems is gapless. Also these systems remain metallic. Indeed it appears that there are many candidates for UDW. The low temperature phase of alpha-(BEDT-TTF)_2KHg(SCN)_4, the antiferromagnetic phase in URu_2Si_2, the CDW in transition metal dichalcogenite NbSe_2, the pseudogap phase in high T_c cuprate superconductors, the glassy phase in organic superconductor kappa-(BEDT-TTF)_2Cu[N(CN)_2]Br. After a brief introduction on UCDW and USDW, we shall discuss some of the above systems, where we believe we have evidence for unconventional density waves.Comment: 11 pages, 5 figure

An Airborne and Vehicular Gamma Survey of Greenham Common, Newbury District and Surrounding Areas

The airborne gamma ray survey recorded more than 40,000 scintillation spectra and 20,000 spectra from semiconductor detectors. The vehicular survey produced a further 1346 and 763 spectral sets respectively. The installation, calibration, recording and analysis followed SURRC procedures which have been developed and validated over many years and are fully documented. Pre flight checks on detector performance for energy calibration, energy resolution and sensitivity were performed on a daily basis. Background readings over water were taken on a daily basis. All data were registered and backed up in duplicate to form a digital archive of the survey. Subsequent analysis and mapping has used a combination of standard procedures established over many years, and new techniques developed to analyse the low energy spectra. All results have been retained to facilitate traceability and further analysis in the future. The sensitivity of the aircraft and vehicle were also checked at Greenham Common by collecting a set of 31 core samples for independent laboratory analysis. The key points arising from the airborne survey of the entire area show that there has been sufficient sensitivity to record variations in the natural background. The levels of 137Cs are consistent with weapons' testing fallout, and are substantially lower than in other parts of the UK and Europe. The average levels of K (0.5%), U (1 ppm) and Th (3 ppm) are lower than national averages and show variations within the area which reflect local geology and landcover. The area as a whole therefore is one of low environmental radiation background compared with national averages. There is no evidence of signals at Greenham Common or in its vicinity which would present a local radiation hazard. However, signals were detected in the vicinity of Harwell and the Rutherford laboratory which would, at the time of the survey, represent radiation projected off-site as a result of materials stored on-site or on-site activities. Examination of the low energy gamma ray spectra recorded from the semiconductor detectors reveals no evidence, within the sensitivity limits of the method, for excess gamma ray signals at the energies associated with 235U around Greenham Common, Newbury and Thatcham. The low energy data are sufficiently sensitive to record variations in the distribution of natural activity in the area. There is tentative evidence for 241Am in the vicinity of AWE Aldermaston. The vehicular survey demonstrated that the grass areas in between the runway and taxi lanes, and around the hardstand associated with the 1958 fire have retained weapons' testing 137Cs. This supports the view that these represent authentic undisturbed areas for sampling. The built surfaces remaining at the time of the survey were of lower natural activity and 137Cs content than their surroundings. High resolution gamma ray spectra at selected sites were also consistent with the known sources of background radioactivity. On the basis of the results, Newbury District and surrounding areas represent an area with low environmental radioactivity compared with national and European averages. There is no evidence to substantiate fears about the quality of the radiation environment in the vicinity of Greenham Common

Chinese older people in Haringey: meeting the needs of an ‘invisible’ community

Haringey has a long established population of Chinese people, some of whom have been living in the borough for many decades. They represent a significant proportion of Haringey’s total population: 1.5% overall but over 2.5% in some wards. Many have become well settled and have been highly successful in business, professions or in other fields but others have experienced exclusion, poverty and isolation. As more of these people are reaching retirement age and beyond, and thus experiencing health and mobility issues connected with ageing, these problems are increasing and are likely to worsen still further in the future. Many of this group also have limited English language skills and thus find it difficult to access appropriate services. In addition, many have low incomes because the nature of their working lives did not allow them to make provision for adequate pensions. In spite of their numbers and the urgency of their needs, Chinese people have had a low profile in relation to the public policy agenda, both in Haringey and in Britain as a whole and have tended to be largely invisible in relation to the planning of services. This research project was conducted by researchers based at Middlesex University in partnership with the Haringey Chinese Centre and we are grateful for the funding received from the Business and Community Interaction programme at Middlesex University which enabled us to carry out this work. The aims were to provide evidence of current and future needs for health and social care services by Chinese older people and to identify issues which policy makers need to be aware of in planning services. This was an exploratory study and limited in scale and thus we cannot claim that it provides a comprehensive picture of the situation of Chinese older people in the borough. Nevertheless, it identified some important issues which deserve more detailed examination from researchers and policy makers. The project took place during a major process of restructuring of services for older people, arising from both national and local policy developments. We hope that our findings will help to inform the development of these services. This report begins by describing the study methods used. We then briefly discuss some of the characteristics of Haringey’s population before focusing more particularly on the Chinese population in Haringey and in London as a whole. We discuss first the different waves of migration which have brought a diverse Chinese population and then focus on the problems of social exclusion and isolation. The next section focuses on the elderly Chinese people, their needs, experience and aspirations and use of services. We then discuss the policy agenda in relation to the care of the elderly and its implications for this group. Finally we draw some general conclusions about the need to plan for this group and suggest some recommendations to policy makers, Chinese organisations and other concerned with the welfare of the elderly

Competing ideologies of Russia's civil society

Many analysts and public opinion makers in the West conflate the notions of Russia’s non-systemic liberal opposition and the country’s civil society. Indeed, despite garnering the support of a minority of Russia’s population, non-systemic liberal opposition represents a well-organized civic group with a clearly articulated agenda and the ability to take action. Yet, does Russia’s civil society end there? A closer look at the country’s politics shows that Russia has a substantial conservative-traditionalist faction that has also developed agenda for action and formulated opinions. This group is anti-liberal rather than illiberal ideologically and pro-strong state/pro a geopolitically independent Russia rather than pro-Kremlin politically. The interaction between liberal and conservative civic groups represents the battle of meanings, ideas, and ethics, and ultimately determines the future trajectory of Russia’s evolution. Thus, the analysis of Russia’s civil society must represent a rather more nuanced picture than a mere study of the liberal non-systemic opposition. This article will examine the complexity of Russia’s civil society scene with reference to the interplay between the liberal opposition and conservative majority factions. The paper will argue that such complexity stems from ideological value pluralism that falls far beyond the boundaries of the liberal consensus, often skewing our understanding of political practice in Russia

Generalized multiresolution analyses with given multiplicity functions

Generalized multiresolution analyses are increasing sequences of subspaces of a Hilbert space \H that fail to be multiresolution analyses in the sense of wavelet theory because the core subspace does not have an orthonormal basis generated by a fixed scaling function. Previous authors have studied a multiplicity function $m$ which, loosely speaking, measures the failure of the GMRA to be an MRA. When the Hilbert space \H is $L^2(\mathbb R^n)$, the possible multiplicity functions have been characterized by Baggett and Merrill. Here we start with a function $m$ satisfying a consistency condition which is known to be necessary, and build a GMRA in an abstract Hilbert space with multiplicity function $m$.Comment: 16 pages including bibliograph

The Experience of Money and Debt Problems in Rural Areas

This current paper is written on the behalf of the Commission for Rural Communities (CRC) to partly address the shortfall in evidence concerning the advice needs of rural communities. Specifically the CRC was interested to gain insight in the following areas: (1) The type of debt problems experienced in rural areas; (2) The prevalence and response to such problems; (3) Issues concerning access to debt advice services in rural areas; and (4) Awareness of advice provision in rural areas

Investigation of Statistical and Imaging Methods for Luminescence Detection of Irradiated Ingredients

This project investigated two potential approaches to improving the reliability of lumines-cence methods for detecting minor irradiated ingredients in foods. Whereas in the 1980’s there were no validated methods for laboratory detection of irradiated foods, work conducted in the UK and elsewhere by the mid 1990’s had resulted in the development of a series of physical, chemical and biological methods capable of detecting a range of irradiated food classes. Of these the luminescence methods embodied in EN1788 (Thermoluminescence) and EN13751 (Photostimulated luminescence) standards have been applied to detection of a vari-ety of products including herbs and spices, and seafood. In common with the other EN stan-dard methods almost all validation work had been originally conducted using pure irradiated or unirradiated ingredients. Yet application experience had shown the presence of mixed products containing both irradiated and unirradiated ingredients. A short study was commis-sioned by MAFF to investigate the impact of blending on standard EN1788 methods, and on the provisional draft EN13751 (the standard having been published in the meantime) method. This showed the impact of dilution of irradiated material between 10% and 0.1% concentra-tions on detection rates, which unsurprisingly are reduced by extreme dilution. UK labelling regulation, both before and after adoption of the European Directive on Food Irradiation, call for labelling of all irradiated ingredients regardless of concentration or origin within the final product. This study was therefore motivated by the recognition of the long term need for im-proved methods to improve reliability at low concentrations. Two complementary approaches were investigated. The project first examined whether TL data collected using the EN1788 method could be enhanced using advanced statistical proce-dures. Data sets from the SURRC TL archive, and from project CSA4790 were used both to define the characteristics of irradiated and unirradiated end members, and to assess classifica-tion methods using the controlled blending experimental data sets of CSA 4790. Multivariate analyses, based on principal components analysis and discriminant analysis of glow curve data; kinetic deconvolution approaches coupled to PCA and DA, and neural analyses were investigated and compared with detection rates achieved using expert visual classification. To complement this experiments were undertaken to explore the potential of using focussed laser stimulation to produce spatially resolved measurements from mineral grains separated from foods. Two systems were evaluated based on IR and visible band lasers. Work was under-taken to explore sample presentation and to assess the ability of this approach to distinguish mixtures of irradiated and unirradiated grains. The statistical work was successful in developing three approaches which could be used for objective identification of irradiated materials. Pure irradiated and unirradiated data sets from 150 sample pairs were obtained having searched the SUERC archive of more than 3500 lu-minescence analyses. These were used to set up multivariate analyses based on the ap-proaches outlined above. Performance in recognising irradiated ingredients using these meth-ods was then assessed with data drawn from the MAFF blending investigation, comprising 160 permutations of irradiated and unirradiated herbs and spices at 10%, 1% and 0.1% con-centrations. It was possible to achieve good detection rates with alatistical approaches, the best approaches inigated being the use of glow curve deconvolution coupwith li discrimination, and the use of neural appros. The absolute performance achieved matched that opert visual clfication utilising the revised EN1788 criterwhich were adopted within the international standauring course of this project. The use of ad-vancedtistical methods, while not adding performance, can pde objective support to visual classifications. During performance assessment it was aloted that theformance of all methods wasficiently close to infer that detections rates are most dependent on the statistical presence or absence of irradiated grains within the extracted samples used for TL analysis. This raises practical suggestions for improving detection rates at low concentrations based on the use of larger samples and more specific mineral separation approaches. These may be worth investigating further. Laser scanning approaches were also investigated using highly focussed laser beams to stimulated luminescence sequentially from different parts of separated mineral samples. Work was conducted using a system which had been developed in earlier work at SUERC, and then followed by additional investigation using an improved instrument built during the project. Initial work confirmed the feasibility of using laser scanning approaches to obtain spatially resolved luminescence data at or near the dimensions of individual mineral grains. Practical obstacles included the recognition that laser scattering from surfaces coated with mineral grains introduced an element of cross-talk between different parts of the sample, and difficulties in accurate re-positioning of the sample using the first generation prototype in-strument. Work was conducted to investigate a series of different sample presentation media to improve the former, and to incorporate high precision mechanical and optoelectronic means of re-positioning samples between initial measurements, external irradiation, and sub-sequent re-measurement. Both IR and visible band semiconductor lasers were investigated with successful production of single grain images. The short and medium term reliability of the lasers used was acceptable. The lasers used both however eventually failed, which sug-gests that long term lifetime may be an issue for further work. Of the two lasers the IR laser in particular gave a good signal to background ratio for discriminating between irradiated and unirradiated grains. Quantitative analysis of the grain resolved images confirms the potential of this approach in identifying minor irradiated components. The overall conclusions of the work are that both statistical approaches and imaging instru-ments are able to enhance current methods. The observation that visual classification can match the performance even of deconvolution or neural approaches suggests that future effort should be directed more towards improvement of grain statistics in conventional measure-ments, and in further development and investigation of imaging approaches. In these ways it can anticipated that the performance of standard luminescence methods for detecting dilute mixtures of irradiated and unirradiated food ingredients could be significantly improved. To do so would further enhance work conducted by FSA and other bodies to ensure that regula-tions governing the use of irradiation in food processing and the labelling of imported foods are followed