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An Ontology for Grounding Vague Geographic Terms
Many geographic terms, such as “river” and “lake”, are vague, with no clear boundaries of application. In particular, the spatial extent of such features is often vaguely carved out of a continuously varying observable domain. We present a means of defining vague terms using standpoint semantics, a refinement of the
philosophical idea of supervaluation semantics. Such definitions can be grounded in actual data by geometric analysis and segmentation of the data set. The issues
raised by this process with regard to the nature of boundaries and domains of logical quantification are discussed. We describe a prototype implementation of a system capable of segmenting attributed polygon data into geographically significant regions and evaluating queries involving vague geographic feature terms
Vortex Rings in two Component Bose-Einstein Condensates
We study the structure of the vortex core in two-component Bose-Einstein
condensates. We demonstrate that the order parameter may not vanish and the
symmetry may not be restored in the core of the vortex. In this case such
vortices can form vortex rings known as vortons in particle physics literature.
In contrast with well-studied superfluid , where similar vortex rings can
be stable due to Magnus force only if they move, the vortex rings in
two-component BECs can be stable even if they are at rest. This beautiful
effect was first discussed by Witten in the cosmic string context, where it was
shown that the stabilization occurs due to condensation of the second component
of the field in the vortex core. This second condensate trapped in the core may
carry a current along the vortex ring counteracting the effect of string
tension that causes the loop to shrink. We speculate that such vortons may have
been already observed in the laboratory. We also speculate that the
experimental study of topological structures in BECs can provide a unique
opportunity to study cosmology and astrophysics by doing laboratory
experiments.Comment: 21 pages, 2 figure
Volunteer role mastery and commitment: Can HRM make a difference?
Although the literature on human resource management (HRM) has provided compelling evidence that certain HRM practices can help employees attain the competence and confidence to carry out their role, less is known about the potential impact of HRM practices on volunteers in the context of non-profit organisations. This study addresses this gap by presenting a model that situates role mastery – operationalised as role clarity and self-efficacy – as its centrepiece. Our model suggests that role mastery leads to commitment to the volunteer organisation and that role mastery can be achieved through training and supportive relationships with paid staff. A dual-mediation analysis of survey data from a humanitarian non-profit organisation in the United Kingdom (n=647) supported our theoretical model. We contribute to volunteering theory and practice by identifying tools that non-profit organisations can employ to maximise the role mastery and commitment of volunteers
The potential of trading activity income to fund third sector organisations operating in deprived areas
In the United Kingdom, as in other countries, Third Sector Organisations (TSOs) have been drawn towards income sources associated with trading activities (Teasdale, 2010), but many remain reliant on grant funding to support such activities (Chell, 2007). Using a multivariate analysis approach and data from the National Survey of Charities and Social Enterprises (NSCSE), it is found that trading activities are used relatively commonly in deprived areas. These organisations are also more likely to attempt to access public sector funds. This suggests policy-makers need to consider the impact of funding cuts on TSOs in the most deprived areas as TSOs are unlikely achieve their objectives without continuing support
Parental approaches to enhancing young people's online safety
Although there is evidence that young people are tech-savvy with the know-how to keep themselves safe online, this review has demonstrated that the technological generational gap remains large.
There are divergent opinions over what constitutes online risks, dangers or threats to young people online. Online environments fostering anonymity, for example, can be perceived as both a risk and benefit to young people. Conversation between young people and adults regarding online safety is imperative to parents understanding cybersafety and young people staying safe online. It remains crucial that research is conducted to explore these questions with adults and young people
I) The Air Ejector. II) Recompression Losses in The Divergent Nozzle
This paper deals with the general characteristics of the air ejector. Except for a few published results on the performance of standard units, information on the subject is very scarce, and the experimental lines followed in the investigation have been arranged to provide a systematic examination of the effect of the various dimensions on the stability and efficiency of operation. Diffuser losses are deduced by analysis from the tests, and the main questions arising in the combining of the operating and induced fluids are discussed. Using a glass-sided diffuser, several aspects of the fluid action are illustrated by the wave formation set up at the nozzle outlet
Ectopic lipid storage in non-alcoholic fatty liver disease is not mediated by impaired mitochondrial oxidative capacity in skeletal muscle
Background and Aims. Simple clinical algorithms including the Fatty Liver Index (FLI) and Lipid Accumulation Product (LAP) have been developed as a surrogate marker for Non-Alcoholic Fatty Liver Disease (NAFLD). These algorithms have been constructed using ultrasonography, a semi-quantitative method. This study aimed to validate FLI and LAP as measures of hepatic steatosis, as measured quantitatively by proton magnetic resonance spectroscopy (1H-MRS).
Methods. Data were collected from 168 patients with NAFLD and 168 controls who had undergone clinical, biochemical and anthropometric assessment in the course of research studies. Values of FLI and LAP were determined, and assessed both as predictors of the presence of hepatic steatosis (liver fat >5.5 %) and of actual liver fat content, as measured by 1H MRS. The discriminative ability of FLI and LAP was estimated using the area under the Receiver Operator Characteristic curve (AUROC). Since FLI can also be interpreted as a predictive probability of hepatic steatosis, we assessed how well calibrated it was in our cohort. Linear regression with prediction intervals was used to assess the ability of FLI and LAP to predict liver fat content.
Results. FLI and LAP discriminated between patients with and without hepatic steatosis with an AUROC of 0.79 (IQR= 0.74, 0.84) and 0.78 (IQR= 0.72, 0.83), although quantitative prediction of liver fat content was unsuccessful. Additionally, the algorithms accurately matched the observed percentages of patients with hepatic steatosis in our cohort.
Conclusions. FLI and LAP may be used clinically, and for metabolic and epidemiological research, to identify patients with hepatic steatosis, but not as surrogates for liver fat content
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