Glomus jugulare tumours : their otological and neurological importance

Perusal of the literature pertaining to glomus jugulare tumours reveals the long interval which usually passes between the onset of symptoms, caused by these slowly growing tumours, and the time of diagnosis. Two case studies illustrating the main different clinical manifestations of these tumours are described. The tumours, histologically, consist of clumps of large polyhedral epithelial cells. The main presenting symptoms may be either otological or neurological, or a mixture of both. This depends on the exact site of origin of the tumour and also on the, direction in which it invades surrounding structures. Neurological manifestations though important develop, as a rule, after the start of otological symptoms. Another peculiar feature of these tumours is their increased incidence in females. The symptoms caused by these tumours have been mistaken for those arising from chronic otitis media, chronic secretory otitis media, acute suppurative otitis media and granulomata of the external auditory canal. Treatment is either surgical or by radio-therapeutic means or by a combination of both, radiotherapy preceeding surgery to reduce the vascularity of the growth. Another method of treatment which may prove to be a useful adjunct is cryosurgery.peer-reviewe

Intelligent transportation infrastructure deployment analysis system

Much of the work on Intelligent Transportation Systems (ITS) to date has emphasized technologies, standards/protocols, architecture, user services, core infrastructure requirements, and various other technical and institutional issues. ITS implementations in the United States and elsewhere in the world have demonstrated benefits in the areas of safety, productivity, efficiency, and environmental impact. However, quantitative benefits and satisfactory cost estimates are not available or cannot be derived for many components of the ITS, whether deployed individually or in some integrated fashion. The limitations of existing analysis and evaluation capabilities coupled with the lack of strong empirical evidence presents a major knowledge and data gap for infrastructure investment decisions involving ITS alternatives. This paper describes the over-arching issues and requirements associated with the analysis capabilities required for a systematic, faithful, and rigorous evaluation of the impacts of deploying ITS in a metropolitan area. It then describes the conceptual framework of a modeling system that will provide a preliminary analysis capability to support ITS deployment analysis and evaluation

A-Site Strain and Displacement in Ba1-xCaxTiO3 and Ba1-xSrxTiO3 and the Consequences for the Curie Temperature

Classical computer simulations are performed on the whole solid solution range of Ba1–xCaxTiO3 (BCT) and Ba1–xSrxTiO3 (BST). The enthalpies and volumes of mixing are produced, and a full local structural analysis is performed. The simulations demonstrate that large degrees of disorder form in the BCT solid solution which leads to distortions in the TiO6 octahedra. Comparing the positions of Sr in BST and Ca in BCT, the position of the Sr cation is largely central within the dodecahedra while the position of the Ca is significantly off-center in many configurations. The relaxation is associated with a shift toward an eight coordinate site compared to a 12 coordinate cation. An empirical model is fitted for predicting the Curie Temperature of the solid solution based on the local structure which shows excellent agreement with experimental values

Implementing collaboration moderator service to support various phases of virtual organisations

This is an Accepted Manuscript of an article published by Taylor & Francis in International Journal of Production Research on Oct 2013, available online: http://www.tandfonline.com/10.1080/00207543.2013.849824Research into moderators, which support collaborative teams by proactively making team members aware of actions or potential problems which may affect them, began in the 1990s, in the context of supporting collaborations during concurrent engineering projects. This paper provides a background to the evolution of moderators and explores their role in supporting virtual organisations. A collaboration moderator (CM) is an evolution of earlier moderators and is capable of behaving differently for different types of users and therefore caters for the varying requirements of individual users depending on the roles they have in the collaborations. This paper describes the architecture and components of a CM from an implementation perspective. Prototype CMs have been developed during the EU-funded SYNERGY project, and two use cases for which the prototype CMs were implemented as a service (a Pre-Creation use case and an Operational use case) are also discussed in this paper

Adjustment of the electric current in pulsar magnetospheres and origin of subpulse modulation

The subpulse modulation of pulsar radio emission goes to prove that the plasma flow in the open field line tube breaks into isolated narrow streams. I propose a model which attributes formation of streams to the process of the electric current adjustment in the magnetosphere. A mismatch between the magnetospheric current distribution and the current injected by the polar cap accelerator gives rise to reverse plasma flows in the magnetosphere. The reverse flow shields the electric field in the polar gap and thus shuts up the plasma production process. I assume that a circulating system of streams is formed such that the upward streams are produced in narrow gaps separated by downward streams. The electric drift is small in this model because the potential drop in narrow gaps is small. The gaps have to drift because by the time a downward stream reaches the star surface and shields the electric field, the corresponding gap has to shift. The transverse size of the streams is determined by the condition that the potential drop in the gaps is sufficient for the pair production. This yields the radius of the stream roughly 10% of the polar cap radius, which makes it possible to fit in the observed morphological features such as the "carousel" with 10-20 subbeams and the system of the core - two nested cone beams.Comment: 8 pages, 1 figur

Influence of enhanced melt supply on upper crustal structure at a mid-ocean ridge discontinuity: A three-dimensional seismic tomographic study of 9°N East Pacific Rise

We present a three-dimensional upper crustal model of the 9°03′N overlapping spreading center (OSC) on the East Pacific Rise that assists in understanding the relationship between melt sills and upper crustal structure at a ridge discontinuity with enhanced melt supply at crustal levels. Our P wave velocity model obtained from tomographic inversion of ∼70,000 crustal first arrival travel times suggests that the geometry of extrusive emplacement are significantly different beneath the overlapping spreading limbs. Extrusive volcanic rocks above the western melt sill are inferred to be thin (∼250 m). More extensive accumulation of extrusives is inferred to the west than to the east of the western melt sill. The extrusive layer inferred above the eastern melt sill thickens from ∼350 (at the neovolcanic axis) to 550 m (to the west of the melt sill). Volcanic construction is likely to be significant in the formation of ridge crest morphology at the OSC, particularly at the tip of the eastern limb. On the basis of our interpretation of the velocity model, we propose that enhanced magma supply at crustal levels at the OSC may provide an effective mechanism for the migration of ridge discontinuities. This “dynamic magma supply model” may explain the commonly observed nonsteady migration pattern of ridge discontinuities by attributing this to the temporal fluctuations in melt availability to the overlapping spreading limbs

An interactive approach for the post-processing in a KDD process

Association rule mining is a technique widely used in the field of data mining, which consists in discovering relationships and/or correlations between the attributes of a database. However, the method brings known problems among which the fact that a large number of association rules may be extracted, not all of them being relevant or interesting for the domain expert. In that context, we propose a practical, interactive and helpful guided approach to visualize, evaluate and compare the extracted rules following a step by step methodology, taking into account the interaction between the industrial domain expert and the data mining expert

Knowledge discOvery And daTa minINg inteGrated (KOATING) Moderators for collaborative projects

This article was published in the serial, International Journal of Production Research [© Taylor and Francis]. The definitive version is available at: http://dx.doi.org/10.1080/00207543.2010.532166A major issue in any multidiscipline collaborative project is how to best share and simultaneously exploit different types of expertise, without duplicating efforts or inadvertently causing conflicts or loss of efficiency through misunderstanding of individual or shared goals. Moderators are knowledge based systems designed to support collaborative teams by raising awareness of potential problems or conflicts. However, the functioning of a Moderator is limited by the knowledge it has about the team members. Knowledge acquisition, learning and updating of knowledge are the major challenges for a Moderator's implementation. To address these challenges a Knowledge discOvery And daTa minINg inteGrated (KOATING) framework is presented for Moderators to enable them to continuously learn from the operational databases of the company and semi-automatically update their knowledge about team members. This enables the reuse of discovered knowledge from operational databases within collaborative projects. The integration of knowledge discovery in database (KDD) techniques into the existing Knowledge Acquisition Module of a moderator enables hidden data dependencies and relationships to be utilised to facilitate the moderation process. The architecture for the Universal Knowledge Moderator (UKM) shows how Moderators can be extended to incorporate a learning element which enables them to provide better support for virtual enterprises. Unified Modelling Language diagrams were used to specify the ways to design and develop the proposed system. The functioning of a UKM is presented using an illustrative example

Application of fast Fourier transforms to EPR spectra of free radicals in solution

A method of reducing EPR spectra of free radicals in solution is presented in detail. This method is based on the use of the fast Fourier transform algorithm and curve fitting in the Fourier space by weighted least-squares minimization. Comparison with previous work is shown for EPR spectra of methyl viologen.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23183/1/0000110.pd