Ryerson University

About: Ryerson University is a education organization based out in Toronto, Ontario, Canada. It is known for research contribution in the topics: Computer science & Population. The organization has 7671 authors who have published 20164 publications receiving 394976 citations. The organization is also known as: Ryerson Polytechnical Institute & Ryerson Institute of Technology.

What makes an incident critical for ambulance workers? Emotional outcomes and implications for intervention.

Abstract: Ambulance workers use the term “critical incident” to refer to a category of workplace stressor. Developing an evidence-based approach to critical incident stress begins with identifying what makes incidents critical. The aim of this qualitative study was to characterize critical incidents as well as elicit suggestions for interventions. We interviewed 60 ambulance-based workers, both front-line and supervisors, and analysed interview transcripts. Having presented their suggestions for interventions more fully elsewhere (Halpern et al, 2009), here we characterize the incidents that emerged as critical and the emotional responses evoked by them. We found they suffered considerable distress from critical incidents and would welcome interventions. Incidents that were identified as critical commonly involved patient death, often combined with poignancy. These events appeared to evoke vulnerable feelings of inability to help and intense compassion, which led to further emotional, cognitive, and behavi...

Anti-jamming Communications Using Spectrum Waterfall: A Deep Reinforcement Learning Approach

Abstract: This letter investigates the problem of anti-jamming communications in dynamic and unknown environment through on-line learning. Different from existing studies which need to know (estimate) the jamming patterns and parameters, we use the spectrum waterfall, i.e., the raw spectrum environment, directly. Firstly, to cope with the challenge of infinite state of raw spectrum information, a deep anti-jamming Q-network is constructed. Then, a deep anti-jamming reinforcement learning algorithm is proposed to obtain the optimal anti-jamming strategies. Finally, simulation results validate the the proposed approach. The proposed approach is relying only on the local observed information and does not need to estimate the jamming patterns and parameters, which implies that it can be widely used various anti-jamming scenarios.

The H275Y Neuraminidase Mutation of the Pandemic A/H1N1 Influenza Virus Lengthens the Eclipse Phase and Reduces Viral Output of Infected Cells, Potentially Compromising Fitness in Ferrets

Abstract: The H275Y amino acid substitution of the neuraminidase gene is the most common mutation conferring oseltamivir resistance in the N1 subtype of the influenza virus. Using a mathematical model to analyze a set of in vitro experiments that allow for the full characterization of the viral replication cycle, we show that the primary effects of the H275Y substitution on the pandemic H1N1 (H1N1pdm09) strain are to lengthen the mean eclipse phase of infected cells (from 6.6 to 9.1 h) and decrease (by 7-fold) the viral burst size, i.e., the total number of virions produced per cell. We also find, however, that the infectious-unit-to-particle ratio of the H275Y mutant strain is 12-fold higher than that of the oseltamivir-susceptible strain (0.19 versus 0.016 per RNA copy). A parallel analysis of the H275Y mutation in the prior seasonal A/Brisbane/59/2007 background shows similar changes in the infection kinetic parameters, but in this background, the H275Y mutation also allows the mutant to infect cells five times more rapidly. Competitive mixed-strain infections in vitro, where the susceptible and resistant H1N1pdm09 strains must compete for cells, are characterized by higher viral production by the susceptible strain but suggest equivalent fractions of infected cells in the culture. In ferrets, however, the mutant strain appears to suffer a delay in its infection of the respiratory tract that allows the susceptible strain to dominate mixed-strain infections.

Effect of zinc interlayer on ultrasonic spot welded aluminum-to-copper joints

Abstract: Dissimilar aluminum (Al) and copper (Cu) metals were joined together using ultrasonic spot welding (USW), a solid state welding technology. The welds were made with and without a zinc (Zn) interlayer to study the microstructural and mechanical properties of weld joints to analyze the effect of the Zn interlayer. USWed Al-to-Cu joints did not produce any intermetallic compounds (IMCs), and only swirls and voids were observed. It was determined through energy dispersive X-ray spectroscopy and X-ray diffraction scans that welds with a Zn interlayer placed in-between the faying surfaces of the base metals formed a composite-like eutectic structure of Al and Al 2 Cu at the center and Al–Zn and CuZn 5 at the edges of the welded joint. Al–Cu joints welded with a Zn interlayer in-between displayed lap shear tensile strengths 25–170% greater than those of the welds without any interlayer.