Are you talking to me? An analysis of journalism conversation on social media

Social media has become a key medium for discussion and dissemination of news stories, fuelled by the low barrier to entry and the ease of interaction. News stories may be propagated through these networks either by official news organisation accounts, by individual journalists or by members of the public, through link sharing, endorsing or commenting. This preliminary research aims to show how computational analysis of large-scale data-sets allows us to investigate the means by which news stories are spread through social media, and how the conversation around them is shaped by journalists and news organisations. Through the capture of more than 11 million tweets relating to 2303 Twitter accounts connected to journalism and news organisations, we are able to analyse the conversation within and around journalism, examining who spreads information about news articles and who interacts in the discussion around them. Capturing the tweets of news organisations and journalists and the replies and retweets of these micro-blogs allows us to build a rich picture of interaction around news media

Birds of a feather locate together? Foursquare checkins and personality homophily

In this paper we consider whether people with similar personality traits have a preference for common locations. Due to the difficulty in tracking and categorising the places that individuals choose to visit, this is largely unexplored. However, the recent popularity of location-based social networks (LBSNs) provides a means to gain new insight into this question through checkins - records that are made by LBSN users of their presence at specific street level locations. A web-based participatory survey was used to collect the personality traits and checkin behaviour of 174 anonymous users, who, through their common check-ins, formed a network with 5373 edges and an approximate edge density of 35%. We assess the degree of overlap in personality traits for users visiting common locations, as detected by user checkins. We find that people with similar high levels of conscientiousness, openness or agreeableness tended to have checked-in locations in common. The findings for extraverts were unexpected in that they did not provide evidence of individuals assorting at the same locations, contrary to predictions. Individuals high in neuroticism were in line with expectations, they did not tend to have locations in common. Unanticipated results concerning disagreeableness are of particular interest and suggest that different venue types and distinctive characteristics may act as attractors for people with particularly selective tendencies. These findings have important implications for decision-making and location

A novel technique for post-pyloric feeding tube placement in critically ill patients: A pilot study

Publisher's copy made available with the permission of the publisher © Australian Society of AnaesthetistsDelivery of enteral nutrition in critically ill patients is often hampered by gastric stasis necessitating direct feeding into the small intestine. Current techniques for placement of post-pyloric feeding catheters are complex, time consuming or both, and improvements in feeding tube placement techniques are required. The Cathlocator™ is a novel device that permits real time localisation of the end of feeding tubes via detection of a magnetic field generated by a small electric current in a coil incorporated in the tip of the tube. We performed a pilot study evaluating the feasibility of the Cathlocator™ system to guide and evaluate the placement of (1) nasoduodenal feeding tubes, and (2) nasogastric drainage tubes in critically ill patients with feed intolerance due to slow gastric emptying. A prospective study of eight critically ill patients was undertaken in the intensive care unit of a tertiary hospital. The Cathlocator™ was used to (1) guide the positioning of the tubes post-pylorically and (2) determine whether nasogastric and nasoduodenal tubes were placed correctly. Tube tip position was compared with data obtained by radiology. Data are expressed as median (range). Duodenal tube placement was successful in 7 of 8 patients (insertion time 12.6 min (5.3-34.4)). All nasogastric tube placements were successful (insertion time 3.4 min (0.6-10.0)). The Cathlocator™ accurately determined the position of both tubes without complication in all cases. The Cathlocator™ allows placement and location of an enteral feeding tube in real time in critically ill patients with slow gastric emptying. These findings warrant further studies into the application of this technique for placement of post-pyloric feeding tubes.R. J. Young, M. J. Chapman, R. Fraser, R. Vozzo, D. P. Chorley, S. Creedhttp://www.aaic.net.au/Article.asp?D=200430

e-Social Science and Evidence-Based Policy Assessment : Challenges and Solutions

Peer reviewedPreprin

Personality and location-based social networks

Location-based social networks (LBSNs) are a recent phenomenon for sharing a presence at everyday locations with others and have the potential to give new insights into human behaviour. To date, due to barriers in data collection, there has been little research into how our personality relates to the categories of place that we visit. Using the Foursquare LBSN, we have released a web-based participatory application that examines the personality characteristics and checkin behaviour of volunteer Foursquare users. Over a four-month period, we examine the behaviour and the “Big Five” personality traits of 174 anonymous users who had collectively checked in 487,396 times at 119,746 venues. Significant correlations are found for Conscientiousness, Openness and Neuroticism. In contrast to some previous findings about online social networks, Conscientiousness is positively correlated with LBSN usage. Openness correlates mainly with location-based variables (average distance between venues visited, venue popularity, number of checkins at sociable venues). For Neuroticism, further negative correlations are found (number of venues visited, number of sociable venues visited). No correlations are found for the other personality traits, which is surprising for Extroversion. The study concludes that personality traits help to explain individual differences in LBSN usage and the type of places visited

CO\u3csub\u3e2\u3c/sub\u3e and tectonic controls on Antarctic climate and ice-sheet evolution in the mid-Miocene

Antarctic ice sheet and climate evolution during the mid-Miocene has direct relevance for understanding ice sheet (in)stability and the long-term response to elevated atmospheric CO2 in the future. Geologic records reconstruct major fluctuations in the volume and extent of marine and terrestrial ice during the mid-Miocene, revealing a dynamic Antarctic ice-sheet response to past climatic variations. We use an ensemble of climate – ice sheet – vegetation model simulations spanning a range of CO2 concentrations, Transantarctic Mountain uplift scenarios, and glacial/interglacial climatic conditions to identify climate and ice-sheet conditions consistent with Antarctic mid-Miocene terrestrial and marine geological records. We explore climatic variability at both continental and regional scales, focusing specifically on Victoria Land and Wilkes Land Basin regions using a high-resolution nested climate model over these domains. We find that peak warmth during the Miocene Climate Optimum is characterized by a thick terrestrial ice sheet receded from the coastline under high CO2 concentrations. During the Middle Miocene Climate Transition, CO2 episodically dropped below a threshold value for marine-based ice expansion. Comparison of model results with geologic data support ongoing Transantarctic Mountain uplift throughout the mid-Miocene. Modeled ice sheet dynamics over the Wilkes Land Basin were highly sensitive to CO2 concentrations. This work provides a continental-wide context for localized geologic paleoclimate and vegetation records, integrating multiple datasets to reconstruct snapshots of ice sheet and climatic conditions during a pivotal period in Earth\u27s history

Desynchronization and Wave Pattern Formation in MPI-Parallel and Hybrid Memory-Bound Programs

Analytic, first-principles performance modeling of distributed-memory parallel codes is notoriously imprecise. Even for applications with extremely regular and homogeneous compute-communicate phases, simply adding communication time to computation time does often not yield a satisfactory prediction of parallel runtime due to deviations from the expected simple lockstep pattern caused by system noise, variations in communication time, and inherent load imbalance. In this paper, we highlight the specific cases of provoked and spontaneous desynchronization of memory-bound, bulk-synchronous pure MPI and hybrid MPI+OpenMP programs. Using simple microbenchmarks we observe that although desynchronization can introduce increased waiting time per process, it does not necessarily cause lower resource utilization but can lead to an increase in available bandwidth per core. In case of significant communication overhead, even natural noise can shove the system into a state of automatic overlap of communication and computation, improving the overall time to solution. The saturation point, i.e., the number of processes per memory domain required to achieve full memory bandwidth, is pivotal in the dynamics of this process and the emerging stable wave pattern. We also demonstrate how hybrid MPI-OpenMP programming can prevent desirable desynchronization by eliminating the bandwidth bottleneck among processes. A Chebyshev filter diagonalization application is used to demonstrate some of the observed effects in a realistic setting.Comment: 18 pages, 8 figure