The path space of a higher-rank graph

We construct a locally compact Hausdorff topology on the path space of a finitely aligned $k$-graph $\Lambda$. We identify the boundary-path space $\partial\Lambda$ as the spectrum of a commutative $C^*$-subalgebra $D_\Lambda$ of $C^*(\Lambda)$. Then, using a construction similar to that of Farthing, we construct a finitely aligned $k$-graph \wt\Lambda with no sources in which $\Lambda$ is embedded, and show that $\partial\Lambda$ is homeomorphic to a subset of \partial\wt\Lambda . We show that when $\Lambda$ is row-finite, we can identify $C^*(\Lambda)$ with a full corner of C^*(\wt\Lambda), and deduce that $D_\Lambda$ is isomorphic to a corner of D_{\wt\Lambda}. Lastly, we show that this isomorphism implements the homeomorphism between the boundary-path spaces.Comment: 30 pages, all figures drawn with TikZ/PGF. Updated numbering and minor corrections to coincide with published version. Updated 29-Feb-2012 to fix a compiling error which resulted in the arXiv PDF output containing two copies of the articl

Alcohol Education and Training in Pre-Registration Nursing: A National Survey to Determine Curriculum Content in the United Kingdom (UK)

Summary BackgroundAlcohol-related harm impacts significantly on the health of the population. Nurses are often among the first health professionals that many patients with alcohol-related problems come into contact with and have been identified as playing a key role but may be ill-prepared to respond. Future nurses need to have the skills, knowledge and clinical confidence to respond to patients suffering from alcohol-related harm. A pre-registration curriculum that ensures a nursing workforce fit for practice in responding to alcohol-related harm is necessary.ObjectivesTo determine the level of alcohol education and training content in the pre-registration curriculum for nursing in the United Kingdom (UK). To establish whether there are variations in the pre-registration curriculum content across the UK.DesignA descriptive study.SettingAll 68 UK Higher Education Institutions offering a total of 111 pre-registration courses for nurses were invited to participate in the study.ParticipantsTwenty nine completed questionnaires were returned, a response rate of 26%. The largest number of identified responders were from England (n=15), with 3 from Scotland and 1 each from Wales and Northern Ireland. Nine Universities chose not to identify themselves.MethodsAn online semi-structured questionnaire survey was used to collect the study data.ResultsTeaching of alcohol and alcohol related harm was mainly delivered during the second year of a pre-registration nursing programme provided mainly to adult and mental health students. Overall, the majority of alcohol related content that is provided within the responding pre-registration nursing courses relates to biophysiology, aetiology, and pharmacological and non-pharmacological interventions.ConclusionThis study highlights the need for a greater and more relevant focus of alcohol education to pre-registration nursing students of all fields of practice incorporating an integrated approach across all years of study

Planting on Rural School Grounds

PDF pages: 2

The changing role of cell culture in the generation of transgenic livestock

Transgenesis may allow the generation of farm animals with altered phenotype, animal models for research and animal bioreactors. Although such animals have been produced, the time and expense involved in generating transgenic livestock and then evaluating the transgene expression pattern is very restrictive. If questions about the ability and efficiency of expression could be asked solely in vitro rapid progress could be achieved. Unfortunately, experiments addressing transcriptional control in vitro have proved unreliable in their ability to indicate whether a transgene will be transcribed or not. However, initial studies suggest that cell culture may be able to predict in vivo post-transcriptional events. We review these issues and propose that strategies which engineer the transgene integration site could enhance the probability for efficient expression. This approach has now become feasible with the development of techniques allowing animals to be generated from somatic cells by nuclear transfer. The important step in this procedure is the use of cells grown in culture as the source of genetic information, allowing the selection of specific transgene integration events. This technology which has dramatically increased the potential use of transgenic livestock for both agricultural and biotechnological applications, is based on standard cell culture methodology. We are now at the start of a new era in large animal transgenics

Stabilization phenomena in Kac-Moody algebras and quiver varieties

Let X be the Dynkin diagram of a symmetrizable Kac-Moody algebra, and X_0 a subgraph with all vertices of degree 1 or 2. Using the crystal structure on the components of quiver varieties for X, we show that if we expand X by extending X_0, the branching multiplicities and tensor product multiplicities stabilize, provided the weights involved satisfy a condition which we call ``depth'' and are supported outside $X_0$. This extends a theorem of Kleber and Viswanath. Furthermore, we show that the weight multiplicities of such representations are polynomial in the length of X_0, generalizing the same result for A_\ell by Benkart, et al.Comment: final version, to appear in International Math Research Notices. 17 pages, 4 figure

Categorification of quantum symmetric pairs I

We categorify a coideal subalgebra of the quantum group of $\mathfrak{sl}_{2r+1}$ by introducing a $2$-category \`a la Khovanov-Lauda-Rouquier, and show that self-dual indecomposable $1$-morphisms categorify the canonical basis of this algebra. This allows us to define a categorical action of this coideal algebra on the categories of modules over cohomology rings of partial flag varieties and on the BGG category $\mathcal{O}$ of type B/C.Comment: final version, to appear in Quantum Topolog

Falling Incapacity Benefit claims in a former industrial city: policy impacts or labour market improvement?

This article provides an in-depth study of Incapacity Benefit (IB) claims in a major city and of the factors behind their changing level. It relates to the regime prior to the introduction of the Employment and Support Allowance (ESA) in 2008. Glasgow has had one of the highest levels of IB in Britain with a peak of almost one fifth of the working age population on IB or Severe Disablement Allowance (SDA). However, over the past decade the number of IB claimants in Glasgow, as in other high claiming areas, has fallen at a faster rate than elsewhere, and Glasgow now has twice the national proportion of working-age people on IB/SDA rather than its peak of three times. The rise in IB in Glasgow can be attributed primarily to deindustrialisation; between 1971 and 1991, over 100,000 manufacturing jobs were lost in the city. Policy response was belated. Lack of local statistics on IB led to a lengthy delay in official recognition of the scale of the issue, and targeted programmes to divert or return IB claimants to work did not begin on any scale until around 2004. Evidence presented in the article suggests that the reduction in claims, which has mainly occurred since about 2003, has been due more to a strengthening labour market than to national policy changes or local programmes. This gives strong support to the view that excess IB claims are a form of disguised unemployment. Further detailed evaluation of ongoing programmes is required to develop the evidence base for this complex area. However, the study casts some doubt on the need for the post-2006 round of IB reforms in high-claim areas, since rapid decline in the number of claimants was already occurring in these areas. The article also indicates the importance of close joint working between national and local agencies, and further development of local level statistics on IB claimants

Interpretation of the OGLE Q2237+0305 microlensing light-curve

The four bright images of the gravitationally lensed quasar Q2237+0305 are being monitored from the ground (eg. OGLE collaboration, Apache Point Observatory) in the hope of observing a high magnification event (HME). Over the past three seasons (1997-1999) the OGLE collaboration has produced microlensing light-curves with unprecedented coverage. These demonstrate smooth, independent (therefore microlensing) variability between the images (Wozniak et al. 2000a,b; OGLE web page). We have retrospectively compared probability functions for high-magnification event parameters with several observed light-curve features. We conclude that the 1999 image C peak was due to the source having passed outside of a cusp rather than to a caustic crossing. In addition, we find that the image C light-curve shows evidence for a caustic crossing between the 1997 and 1998 observing seasons involving the appearance of new critical images. Our models predict that the next image C event is most likely to arrive 500 days following the 1999 peak, but with a large uncertainty (100-2000 days). Finally, given the image A light-curve derivative at the end of the 1999 observing season, our modelling suggests that a caustic crossing will occur between the 1999 and 2000 observing seasons, implying a minimum for the image A light-curve ~1-1.5 magnitudes fainter than the November 1999 level.Comment: 11 pages, 15 figures. Accepted for publication in M.N.R.A.