Protostellar Jet and Outflow in the Collapsing Cloud Core

We investigate the driving mechanism of outflows and jets in star formation process using resistive MHD nested grid simulations. We found two distinct flows in the collapsing cloud core: Low-velocity outflows (sim 5 km/s) with a wide opening angle, driven from the first adiabatic core, and high-velocity jets (sim 50 km/s) with good collimation, driven from the protostar. High-velocity jets are enclosed by low-velocity outflow. The difference in the degree of collimation between the two flows is caused by the strength of the magnetic field and configuration of the magnetic field lines. The magnetic field around an adiabatic core is strong and has an hourglass configuration. Therefore, the low-velocity outflow from the adiabatic core are driven mainly by the magnetocentrifugal mechanism and guided by the hourglass-like field lines. In contrast, the magnetic field around the protostar is weak and has a straight configuration owing to Ohmic dissipation in the high-density gas region. Therefore, high-velocity jet from the protostar are driven mainly by the magnetic pressure gradient force and guided by straight field lines. Differing depth of the gravitational potential between the adiabatic core and the protostar cause the difference of the flow speed. Low-velocity outflows correspond to the observed molecular outflows, while high-velocity jets correspond to the observed optical jets. We suggest that the protostellar outflow and the jet are driven by different cores (the first adiabatic core and protostar), rather than that the outflow being entrained by the jet.Comment: To appear in the proceedings of the "Protostellar Jets in Context" conference held on the island of Rhodes, Greece (7-12 July 2008

Aetiology of sudden cardiac death in sport: a histopathologist's perspective.

In the UK, when a young person dies suddenly, the coroner is responsible for establishing the cause of death. They will ask a consultant pathologist to carry out an autopsy in order to ascertain when, where and how that person died. Once the cause of death is established and is due to natural causes, the coroner can issue a death certificate. Importantly, the coroner is not particularly interested in the cause of death as long as it is due to natural causes, which avoids the need for an inquest (a public hearing about the death). However, if no identifiable cause is established at the initial autopsy, the coroner can refer the heart to a cardiac pathologist, since the cause of death is usually due to heart disease in most cases. Consultant histopathologists are responsible for the analysis of human tissue from both living individuals and the dead in order to make a diagnosis of disease. With recent advancements in the management protocols for routine autopsy practice and assessment following the sudden death of a young individual, this review describes the role of the consultant histopathologist in the event of a sudden death of a young athletic individual, together with the older middle-aged 'weekend warrior' athlete. It provides concise mechanisms for the main causes of sudden cardiac death (including coronary artery disease, cardiomyopathies, valve abnormalities, major vessel ruptures and electrical conduction abnormalities) based on detailed autopsy data from our specialised cardiac pathology laboratory. Finally, the review will discuss the role of the histopathologist in the event of a 'negative' autopsy

Towards an archaeology of media ecologies : the case of Italian free radios

This article looks at the contemporary reinvention of the term Media Ecologies in the work of Matthew Fuller, arguing that its provenance is less form Postman's Media Ecology Association andmore form the work of Felix Guattari. It then presents an account of free radios in Italy and France in the 1970s and contemporary pirate radio as exemplary cases of media ecologies in Fuller's sense of the term

Achieving IT diffusion within the fragments: an IT culture perspective

Many organizations still fail to make a return from the huge investments they make in implementing complex Information Technology (IT). This is usually due to cultural forces that inhibit the level of usage required to facilitate IT Diffusion. An emerging stream of research highlights the IT culture perspective, a perspective vital for understanding individuals’ social practices when they interact with IT. This paper adopted a case study approach to explore how the IT culture perspective may explain how organizational diffusion of an IT may happen despite opposing cultural forces causing a stalemate to the diffusion process. This study identified three IT culture archetypes - embracing, rejecting and confused, depicting a fragmented IT culture during the adaption, acceptance and routinization stages of diffusion of an IT. This study highlights how a salient element of a fragmented IT culture-embracing IT culture archetype could explain how diffusion of an IT happened despite the manifestations of negative IT culture archetypes - ‘confused’ and ‘rejecting’ during the diffusion process

Designing a novel virtual collaborative environment to support collaboration in design review meetings

Project review meetings are part of the project management process and are organised to assess progress and resolve any design conflicts to avoid delays in construction. One of the key challenges during a project review meeting is to bring the stakeholders together and use this time effectively to address design issues as quickly as possible. At present, current technology solutions based on BIM or CAD are information-centric and do not allow project teams to collectively explore the design from a range of perspectives and brainstorm ideas when design conflicts are encountered. This paper presents a system architecture that can be used to support multi-functional team collaboration more effectively during such design review meetings. The proposed architecture illustrates how information-centric BIM or CAD systems can be made human- and team-centric to enhance team communication and problem solving. An implementation of the proposed system architecture has been tested for its utility, likability and usefulness during design review meetings. The evaluation results suggest that the collaboration platform has the potential to enhance collaboration among multi-functional teams

Neologistic jargon aphasia and agraphia in primary progressive aphasia

The terms 'jargon aphasia' and 'jargon agraphia' describe the production of incomprehensible language containing frequent phonological, semantic or neologistic errors in speech and writing, respectively. Here we describe two patients with primary progressive aphasia (PPA) who produced neologistic jargon either in speech or writing. We suggest that involvement of the posterior superior temporal-inferior parietal region may lead to a disconnection between stored lexical representations and language output pathways leading to aberrant activation of phonemes in neologistic jargon. Parietal lobe involvement is relatively unusual in PPA, perhaps accounting for the comparative rarity of jargon early in the course of these diseases. (C) 2008 Elsevier B.V. All rights reserved

Usual Tumor at an Unusual Site - A Leiomyoma Masquerading as a Urethral Polyp.

Polyps and papillomas encompass the most common benign tumors of the urethra.Leiomyoma of urethra is a rare clinical entity which can be diagnosed only with histopathological examination and only around 35 such cases have been reported worldwide

Community structure detection in the evolution of the United States airport network

This is the post-print version of the Article. Copyright © 2013 World Scientific PublishingThis paper investigates community structure in the US Airport Network as it evolved from 1990 to 2010 by looking at six bi-monthly intervals in 1990, 2000 and 2010, using data obtained from the Bureau of Transportation Statistics of the US Department of Transport. The data contained monthly records of origin-destination pairs of domestic airports and the number of passengers carried. The topological properties and the volume of people traveling are both studied in detail, revealing high heterogeneity in space and time. A recently developed community structure detection method, accounting for the spatial nature of these networks, is applied and reveals a picture of the communities within. The patterns of communities plotted for each bi-monthly interval reveal some interesting seasonal variations of passenger flows and airport clusters that do not occupy a single US region. The long-term evolution of the network between those years is explored and found to have consistently improved its stability. The more recent structure of the network (2010) is compared with migration patterns among the four US macro-regions (West, Midwest, Northeast and South) in order to identify possible relationships and the results highlight a clear overlap between US domestic air travel and migration