597 research outputs found
Searching for Serendipitous Analogies
Analogical reasoning is an acknowledged process
behind many episodes of creativity. Typically, the creator chances
upon information unrelated to the given problem – and solves the
problem by analogy with this accidental source of inspiration.
Current models of analogical retrieval do not explain how
semantically unrelated source domains are retrieved. We present
the RADAR algorithm that maps domains into a separate structure
space, where domains with similar topological attributes are colocated.
Each axis in structure space records the occurrence
frequency of that feature in each domain. Nearest neighbour
retrieval in structure space identifies structurally similar domains -
from a diversity of semantic backgrounds. Structure based retrieval
opens the possibility for creating an analogy model with far greater
creativity potential than human reasoning
Features of Structure for Anaology Retrieval
Spontaneously retrieving analogies from
presented problem data is an important phase of
analogical reasoning, influencing many related
cognitive processes. Existing models have
focused on semantic similarity, but structural
similarity is also a necessary requirement of any
analogical comparison. We present a new
technique for performing structure based analogy
retrieval. This is founded upon derived attributes
that explicitly encode elementary structural
qualities of a domains representation. Crucially,
these attributes are unrelated to the semantic
content of the domain information, and encode
only its structural qualities. We describe a
number of derived attributes and detail the
computation of the corresponding attribute
values. We examine our models operation,
detailing how it retrieves both semantically
related and unrelated domains. We also present a
comparison of our algorithms performance with
existing models, using a structure rich but
semantically impoverished domai
Oral health and pathology: a macrophage account.
Macrophages are present in healthy oral mucosa and their numbers increase dramatically during disease. They can exhibit a diverse range of phenotypes characterised as a functional spectrum from pro-inflammatory to anti-inflammatory (regulatory) subsets. This review illustrates the role of these subsets in the oral inflammatory disease lichen planus, and the immunosuppressive disease oral squamous cell carcinoma (SCC). We conclude that the role of macrophages in driving progression in oral disease identifies them as potential therapeutic targets for a range of oral pathologies
Restenosis and its determinants in first and repeat coronary angioplasty
Restenosis is the main problem limiting long-term success of percutaneous transluminal coronary angioplasty (PTCA) and is most accurately evaluated by follow-up angiography. We compared the primary and long-term results of angioplasty in 268 consecutive patients (293 segments) with first PTCA (PTCA 1, angiographic follow-up 98%) and in 66 patients (76 segments) with repeat PTCA after restenosis (PTCA 2, angiographic follow-up 92%). Forty clinical, angiographic and procedural factors were assessed in relation to outcome. Primary success rate was higher in PTCA 2 (91% vs 67.5%) and major complications were fewer (4.5% vs 16%).Higher inflation pressure (7.9 ± 2.3 vs 6.8 ± 1.8 atm, P70%) after PTCA 1 and after PTC A 2 (27% vs 36%, P = NS) and the mean time to recurrence (4.7 vs 5.3 months, P = NS) were similar. Procedural factors were the main determinants of long-term success in primary PTCA. The restenosis risk was independently related to residual stenosis >45% (P<0.001), variant angina (P<0.05) and multivessel disease (P<0.05) after PTCA 1 and to male sex (P<0.001) and higher inflation pressure (P<0.05) after PTCA 2. Mild to moderate intimal tearing was associated with less restenosis after PTC A 1, but not after PTCA 2. Including 9 patients (10 segments) with a third PTCA, 70% of the 66 patients with repeat PTCA had a successful long-term outcome. Repeat angioplasty should therefore be considered as an integral part of PTCA therapy. Restenosis however remains a major concern. An optimal primary result with a minimal residual stenosis is decisive for first PTCA, whereas avoidance of a dissection by using lower inflation pressure on a restenosis might improve the long-term outcome of repeat PTC
Relationship between MRI Derived Right Ventricular Mass and Left Ventricular Involvement in Patients with Anderson-Fabry Disease
Poster presentationpublished_or_final_versio
STORMTOOLS: Coastal Environmental Risk Index (CERI)
One of the challenges facing coastal zone managers and municipal planners is the development of an objective, quantitative assessment of the risk to structures, infrastructure, and public safety that coastal communities face from storm surge in the presence of changing climatic conditions, particularly sea level rise and coastal erosion. Here we use state of the art modeling tool (ADCIRC and STWAVE) to predict storm surge and wave, combined with shoreline change maps (erosion), and damage functions to construct a Coastal Environmental Risk Index (CERI). Access to the state emergency data base (E-911) provides information on structure characteristics and the ability to perform analyses for individual structures. CERI has been designed as an on line Geographic Information System (GIS) based tool, and hence is fully compatible with current flooding maps, including those from FEMA. The basic framework and associated GIS methods can be readily applied to any coastal area. The approach can be used by local and state planners to objectively evaluate different policy options for effectiveness and cost/benefit. In this study, CERI is applied to RI two communities; Charlestown representing a typical coastal barrier system directly exposed to ocean waves and high erosion rates, with predominantly low density single family residences and Warwick located within Narragansett Bay, with more limited wave exposure, lower erosion rates, and higher residential housing density. Results of these applications are highlighted herein
Cardiovascular magnetic resonance demonstration of the spectrum of morphological phenotypes and patterns of myocardial scarring in Anderson-Fabry disease
published_or_final_versio
- …