Conformal Parametrisation of Loxodromes by Triples of Circles

We provide a parametrisation of a loxodrome by three specially arranged cycles. The parametrisation is covariant under fractional linear transformations of the complex plane and naturally encodes conformal properties of loxodromes. Selected geometrical examples illustrate the usage of parametrisation. Our work extends the set of objects in Lie sphere geometry---circle, lines and points---to the natural maximal conformally-invariant family, which also includes loxodromes.Comment: 14 pages. 9 PDF in four figures, AMS-LaTe

A critical review of PASBio's argument structures for biomedical verbs

BACKGROUND: Propositional representations of biomedical knowledge are a critical component of most aspects of semantic mining in biomedicine. However, the proper set of propositions has yet to be determined. Recently, the PASBio project proposed a set of propositions and argument structures for biomedical verbs. This initial set of representations presents an opportunity for evaluating the suitability of predicate-argument structures as a scheme for representing verbal semantics in the biomedical domain. Here, we quantitatively evaluate several dimensions of the initial PASBio propositional structure repository. RESULTS: We propose a number of metrics and heuristics related to arity, role labelling, argument realization, and corpus coverage for evaluating large-scale predicate-argument structure proposals. We evaluate the metrics and heuristics by applying them to PASBio 1.0. CONCLUSION: PASBio demonstrates the suitability of predicate-argument structures for representing aspects of the semantics of biomedical verbs. Metrics related to theta-criterion violations and to the distribution of arguments are able to detect flaws in semantic representations, given a set of predicate-argument structures and a relatively small corpus annotated with them

Formal verification of CNL health recommendations

This research is partially supported by EPSRC grant EP/M014290/1.Clinical texts, such as therapy algorithms, are often described in natural language and may include hidden inconsistencies, gaps and potential deadlocks. In this paper, we propose an approach to identify such problems with formal verification. From each sentence in the therapy algorithm we automatically generate a parse tree and derive case frames. From the case frames we construct a state-based representation (in our case a timed automaton) and use a model checker (here UPPAAL) to verify the model. Throughout the paper we use an example of the algorithm for blood glucose lowering therapy in adults with type 2 diabetes to illustrate our approach.Postprin

Moving beyond the distinction between concrete and abstract concepts

From the perspective of the situated conceptualization framework, the primary purpose of concepts is for categorizing and integrating elements of situations to support goal-directed action (including communication and social interaction). To the extent that important situational elements are categorized and integrated properly, effective goal-directed action follows. Over time, frequent patterns of co-occurring concepts within situations become established in memory as situated conceptualizations, conditioning the conceptual system and producing habitual patterns of conceptual processing. As a consequence, individual concepts are most basically represented within patterns of concepts that become entrained with specific kinds of physical situations. In this framework, the concrete versus abstract distinction between concepts is no longer useful, with two other distinctions becoming important instead: (i) external versus internal situational elements, (ii) situational elements versus situational integrations. Whereas concepts for situational elements originate in distributed neural networks that provide continual feeds about components of situations, concepts for situational integrations originate in association areas that establish temporal co-occurrence relations between situational elements, both external and internal. We propose that studying concepts in the context of situated action is necessary for establishing complete accounts of them, and that continuing to study concepts in isolation is likely to provide relatively incomplete and distorted accounts. This article is part of the theme issue ‘Varieties of abstract concepts: development, use and representation in the brain’

The more things change ... the more things change: developmental plasticity of tumor-initiating mammary epithelial cells

In our haste to find and eliminate breast cancer stem cells, it appears as though we may have missed something. Contrary to current thought, a recent paper by Meyer and colleagues demonstrates developmental plasticity of breast cancer cells with respect to the CD24 cell surface marker, such that CD44pos; CD24pos and CD44pos; CD24low/- cells are able to give rise to one another in an activin/nodal-dependent manner, and that cells derived from single cells of either phenotype are capable of forming tumors as xenografts. If confirmed clinically, these data imply that simply targeting the CD44pos; CD24low/- breast cancer stem cell for breast cancer treatment may be destined to fail unless this plasticity is taken into account and prevented

Preschool Teachers’ Perspectives About the Engagement of Immigrant and Non-Immigrant Parents in Their Children’s Early Education

The present study explores the perceptions of teachers about the engagement of immigrant and non-immigrant parents in preschool. Data were drawn from a larger evaluation study of a government initiative for preschools in Germany, which was designed to foster inclusive pedagogy and parent cooperation. In these analyses, teachers’ perceptions of the engagement of immigrant parents and non-immigrant parents were rated for each parent group, on a 10-item measure, to identify how teacher ratings varied for the different parent groups. Data from 1397 preschool teachers, employed across 203 preschools, were analyzed using multilevel modeling. This statistical approach takes account of the clustered nature of the data. Teacher ratings of engagement for immigrant and non-immigrant parent groups differed between preschools. Most variability in the ratings could be ascribed to preschool characteristics. In preschools, in which staff held a shared understanding of dealing with cultural diversity and in which the director of the preschool had a multicultural mindset, teachers perceived engagement of parents more positively, especially for immigrant parents. Overall, the findings identified the importance of self-efficacy for inclusion and more positive beliefs about multiculturalism among preschool teachers. Such qualities are important for working with all parents. However, unfavorable social structures, such as those found in disadvantaged areas, may present major challenges for parent cooperation and engagement

Mind-modelling with corpus stylistics in David Copperfield

We suggest an innovative approach to literary discourse by using corpus linguistic methods to address research questions from cognitive poetics. In this article, we focus on the way that readers engage in mind-modelling in the process of characterisation. The article sets out our cognitive poetic model of characterisation that emphasises the continuity between literary characterisation and real-life human relationships. The model also aims to deal with the modelling of the author’s mind in line with the modelling of the minds of fictional characters. Crucially, our approach to mind-modelling is text-driven. Therefore we are able to employ corpus linguistic techniques systematically to identify textual patterns that function as cues triggering character information. In this article, we explore our understanding of mind-modelling through the characterisation of Mr. Dick from David Copperfield by Charles Dickens. Using the CLiC tool (Corpus Linguistics in Cheshire) developed for the exploration of 19th-century fiction, we investigate the textual traces in non-quotations around this character, in order to draw out the techniques of characterisation other than speech presentation. We show that Mr. Dick is a thematically and authorially significant character in the novel, and we move towards a rigorous account of the reader’s modelling of authorial intention

Tolerance and cross-tolerance to neurocognitive effects of THC and alcohol in heavy cannabis users

and cross-tolerance to neurocognitive effects of THC and alcohol in heavy cannabis user

Do intoxicated witnesses produce poor facial composite images?

The effect of alcohol intoxication on witness memory and performance has been the subject of research for some time, however, whether intoxication affects facial composite construction has not been investigated. Intoxication was predicted to adversely affect facial composite construction. Thirty-two participants were allocated to one of four beverage conditions consisting of factorial combinations of alcohol or placebo at face encoding, and later construction. Participants viewed a video of a target person and constructed a composite of this target the following day. The resulting images were presented as a full face composite, or a part face consisting of either internal or external facial features to a second sample of participants who provided likeness ratings as a measure of facial composite quality. Intoxication at face encoding had a detrimental impact on the quality of facial composites produced the following day, suggesting that alcohol impaired the encoding of the target faces. The common finding that external compared to internal features are more accurately represented was demonstrated, even following alcohol at encoding. This finding was moderated by alcohol and target face gender such that alcohol at face encoding resulted in reduced likeness of external features for male composite faces only. Moderate alcohol intoxication impairs the quality of facial composites, adding to existing literature demonstrating little effect of alcohol on line-up studies. The impact of intoxication on face perception mechanisms, and the apparent narrowing of processing to external face areas such as hair, is discussed in the context of alcohol myopia theory