Introduction: Cognitive processing theories postulate that decision making depends on both fast and slow thinking. Experienced physicians (EPs) make diagnoses quickly and with less effort by using fast, intuitive thinking, whereas inexperienced medical students rely on slow, analytical thinking. This study used a cognitive task analysis to examine EPs cognitive processes and ability to provide knowledge translation to learners. Methods: A novel mind mapping approach was used to examine how EPs translate their clinical reasoning to learners, when evaluating a patient for a possible venous thromboembolism (VTE). Nine EPs were interviewed and shown two different videos of a medical student patient interview (randomized from six possible videos). Results: EPs were asked to demonstrate their clinical approach to the scenario using a mind map, assuming they were teaching a learner in the Emergency Department. EPs were later re-interviewed to examine response stability, and given the opportunity to make clarifying or substantive mind map modifications. Maps were broken into component pieces and analyzed using mixed-methods techniques. A mean of 15.7 component pieces were identified within each mind map (standard deviation (SD) 7.8). Maps were qualitatively coded, with a mean of 2.8 clarifying amendments (e.g. adding a time course caveat) (SD 1.5-5.75) and 4.4 substantive modifications (e.g. changing the flow of the map) (SD 2-5). Conclusion: Resulting mind maps displayed significant heterogeneity in teaching points and the degree to which EPs used slow thinking. EPs frequently made fast thinking jumps, although learners could prompt slow thinking by questioning unclear points. This is particularly important as learners engage in cognitive apprenticeship throughout their training. An improved understanding of EPs cognitive processes through mind mapping will allow learners to improve their own clinical reasoning (Merrit et al., 2017). Educating EPs on these processes will allow modification of their teaching styles to better suit learners.

Introduction: Developing structured online educational curricula that meet learner needs is challenging. Thrombosis and bleeding are areas of innovation and change in emergency medicine. We aimed to determine the learning needs of the Free Open Access Medical education (FOAM) community with the subsequent goal of developing structured curricula to meet them. Methods: A Massive Online Needs Assessment (MONA) was conducted to determine the perceived and unperceived educational needs in thrombosis and bleeding. The survey was designed by a multidisciplinary team of experts and was open from September 20 to December 10, 2016. The survey requested limited demographic information and contained questions to identify topics of interest. Respondents’ baseline knowledge and unperceived needs were assessed using 5 case scenarios containing 3 questions each. Knowledge gaps were defined a priori as topics where <50% of participants answered correctly. Results: We received 198 complete responses by staff physicians (n=109), residents (n=46), medical students (n=29) and allied health professionals (n=14) from 20 countries. 116/198 responses were from people working in emergency medicine. Topics of interest to participants included choice of anticoagulants, interruption of anticoagulation, management of bleeding and monitoring anticoagulation. Knowledge gaps were identified in 4 main areas including interruption of anticoagulation, management of bleeding (including reversal of anticoagulation and massive transfusion), inherited thrombophilia, and screening for malignancy in acute thrombosis. Conclusion: We have identified six priority topics to cover in our future online Thrombosis and Bleeding curriculum by surveying the online medical community. Although perceived and unperceived needs showed high congruence, two priority topics were only identified by assessing unperceived needs.

Introduction/Innovation Concept: The boom in online educational resources for medical education over the past decade has changed how physicians learn and keep up to date with new literature. While nearly all emergency medicine residents use online resources, few of these resources were designed to target knowledge gaps. Novel methods are required to identify learning needs to allow the targeted development of learner-centered curricula. Methods: A multidisciplinary team attempted to determine the feasibility of conducting a Massive Online Needs Assessment (MONA) to assess the perceived and unperceived educational needs in thrombosis and bleeding. An open, online survey was launched via Google Forms and disseminated using the online educational resource CanadiEM.org and social media platforms Twitter and Facebook with the goal of reaching participants of the Free Open Access Medical education (FOAM) community. Curriculum, Tool, or Material: The survey was designed to identify knowledge gaps and contained demographic, free text, and multiple choice questions. It took individuals approximately 30 minutes to complete and was incentivized with entry into a draw for one of four $250 Amazon Gift cards. Feasibility was defined a priori as 150 responses from at least 4 specialties in 4 or more countries. This sample was deemed the minimum number required to identify knowledge gaps (defined as <50% correct answers). The survey was open from September 20 to December 10, 2016. We received 198 complete responses from 20 countries. Respondents included staff physicians (n=109), residents (n=46), medical students (n=29), nurses (n=8), paramedics (n=4), a pharmacist (n=1) and a physician assistant (n=1). The survey entry page hosted on CanadiEM.org received page views from 866 unique IP addresses. As such, a conservative approximation of the completion rate per unique viewer was 22% (198/866). Conclusion: It is feasible to use a MONA to collect data on the perceived and unperceived needs of an online community. Such needs assessments could be used to make online resources more learner-centered.

Two non-invasive optical Schlieren methods have been adapted to visualize brine channel development and convective processes in experimentally grown sea ice obtained when a NaCl aqueous solution is cooled from above in a quasi-two-dimensional Hele–Shaw cell. The two different visualization methods, i.e. traditional and synthetic Schlieren optical imaging, produce high spatial resolution images of transport processes during ice growth, without any external perturbation. These images allow observations of the flow dynamics simultaneously within the ice layer, around the ice/water interface, and in the liquid water layer, revealing connections between the processes occurring within the two phases. Results from these methods show that desalination of the growing ice layer occurs by two concurrent, yet independent, mechanisms: (1) boundary layer convection persisting throughout the ice growth period, with short fingers present just below the ice/water interface, and (2) gravity-driven drainage from the brine channels producing deep penetrating convective streamers, which appear after a given time from the beginning of ice growth. The improved visualization and qualitative characterization of these processes show that Schlieren optical methods have exciting potential applications for future study of convective processes during sea-ice growth.

The well-known recurrent nova T Pyx has brightened by 7 magnitudes, starting on 2011 April 14, its first eruption since 1966. T Pyx is unique amongst recurrent novæ in being surrounded by a nebula formed of material ejected during previous eruptions. The latest eruption therefore offers the rare opportunity to observe a light echo sweeping through the existing shell, and a new one forming. The sudden exposure of the existing shell to high-energy light is expected to result in a change of the dust morphology as well as in the part destruction of molecules. We observe this process in the near- and mid-IR during several epochs using ESO's VLT instruments Sinfoni, Visir and Isaac. Unfortunately, in the data analysed so far we only have a tentative detection in Brα from the shell, so might in the end have to be content with upper limits for the emission from the various molecular bands and ionised lines.

The aim of this study was to investigate psychosocial, cognitive, and motor functioning in patients clinically suspected of Sotos syndrome and to examine differences between patients with deletions or mutations of the gene encoding nuclear SET domain-containing protein 1 (NSD1; the major cause of the syndrome) and those without such alterations. Twenty-nine participants (21 males, 8 females) clinically suspected of Sotos syndrome (mean age 11y 10mo [SD 10y 11mo], range 1y 10mo–48y 5mo) were divided into an NSD1 mutation group (n=12; 8 males, 4 females) and an NSD1 non-mutation group (n=17; 13 males, 4 females). Intelligence, behaviour problems, attention-deficit–hyperactivity disorder (ADHD) symptoms, temperament, adaptive behaviour, and motor functioning were assessed with an extensive test battery. Scores were compared with those of control groups, and scores of the two subgroups were compared with each other. The mean IQ in the 21 individuals tested was 76 (SD 16; range 47–105). High rates of behaviour problems were found and patients lagged 1y 7mo to 2y 7mo behind in aspects of adaptive behaviour. In comparison with a control group of patients with a learning disability, motor functioning was better. NSD1 mutation compared with NSD1 non-mutation patients showed easier temperament, and fewer NSD1 mutation patients scored in the clinical range for ‘total behaviour problems’ (3/11 vs 13/17), ‘internalizing behaviour’ (2/11 vs 11/17), and ADHD (0/9 vs 4/15).

About 20% of the high mass O-type stars in the Galaxy are found outside stellar clusters and associations. In the solar neighbourhood this fraction amounts to 43 O-type stars. In the framework of high-mass star formation, we search for the origins of these stars. We aim at separating the O-type field stars from runaway O-type stars, where the former does not betray any indication of past dynamical interactions resulting in their present field location. We specifically search for the presence of stellar clusters, but also evaluate spatial velocities, distance from Galactic plane, locations in the Galaxy with respect to young stellar clusters. Among our sample of 43, we find that 5 stars are in fact observed in the K-band to be members of previously unnoticed small clusters. On the other hand it is plausible that nearly half the sample (22 objects) could have undergone a dynamical ejection from a young cluster. Based on the current available data, ${\sim }4%$ of the Galactic O-type stars cannot be associated with a stellar cluster. Finally by assuming that stars form in clusters with a power law in membership number with index −1.7 down to “clusters” consisting of single stars, we calculate the expected statistics regarding isolated O stars and O stars in OB-associations. We conclude that the results of the calculations are consistent with the observed statistics of O-type stars.

A mathematical model that takes transmission by sexual contact and vertical transmission into account was employed to describe the transmission dynamics of hepatitis B virus (HBV) and vaccination against it. The model is an extension of a model by Williams et al. (Epidemiol Infect 1996; 116; 71–89) in that it takes immigration of hepatitis B carriers from countries with higher prevalence into account. Model parameters were estimated from data from The Netherlands where available. The main results were that, given the estimates for the parameters describing sexual behaviour in The Netherlands, the basic reproduction number R0 is smaller than 1 in the heterosexual population. As a consequence, the immigration of carriers into the population largely determines the prevalence of HBV carriage and therefore limits the possible success of universal vaccination. Taking into account the prevalence of hepatitis B carriage among immigrants and an age-dependent probability of becoming a carrier after infection, we estimate that a fraction of between 5 and 10% of carrier states could be prevented by universal vaccination.

We compared gastroenteritis cases that consulted a general practitioner (GP) with those who did not in a community-based study and also with those in a GP-based study. We aimed to identify factors associated with consultation, and with inclusion of cases by GPs, and secondly to study the effects on the frequency of detection of pathogens. Furthermore, we estimated the under-ascertainment by GPs. Both studies were performed in The Netherlands in the same population in an overlapping time-period. Overall, 5% of community cases consulted a GP. Cases who consulted suffered from more severe episodes than non-consulting cases. Inclusion of cases by GPs, instead of a study team, caused a selection of more severe cases with more chronic symptoms. When extrapolating data from GP-based studies, it should be taken into account that, in general practice, gastroenteritis due to bacteria and Giardia lamblia is a relatively large proportion of that in the community and gastroenteritis due to Norwalk-like viruses is a relatively small proportion. The incidence of gastroenteritis in general practices was estimated between 14 and 35 per 1000 person years.

Stoichiometric iron nitride layers have been synthesized by high dose, high energy nitrogen implantation into Fe using a two-step implantation process. First, a nitrogen preimplantation at ~100 °C is used to form nitride precipitates. A low temperature is necessary to restrict the nitrogen mobility. Second, 1 MeV implantation at ~300 °C leads to the formation of a stoichiometric γ′–Fe4N layer at the position of the preimplanted N atoms. Growth of this nitride layer proceeds by diffusion of the implanted N through either the α–Fe matrix (for 200 or 500 keV preimplantations) or the nitride layer itself (for 1 MeV preimplantation). During annealing above 350 °C the γ′ layers dissolve in a planar fashion, characterized by an activation energy of 2.3 eV. Phase formation during preimplantation and phase transformations during subsequent annealing or hot implantation can be understood from the thermodynamics for the Fe–N system, while the kinetics of layer growth is influenced by the beam-induced defects. The experiment and model suggest that γ′ is not a thermodynamically stable phase below 310 ± 10 °C and should decompose into α (ferrite) and ∊ nitride.

Structural relaxation of amorphous Si is studied in the temperature range 500-850 °C using Raman spectroscopy. The minumum value for the Raman peakwidth that can be obtained is inversely proportional to the anneal temperature. The relaxation process is basically the same in a-Si prepared by ion implantation and by vacuum evaporation.