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Introduction: One in nine (11.7%) people in Saskatchewan identifies as First Nations. In Canada, First Nations people experience a higher burden of cardiovascular disease when compared to the general population, but it is unknown whether they have different outcomes in out of hospital cardiac arrest (OHCA). Methods: We reviewed pre-hospital and inpatient records of patients sustaining an OHCA between January 1st, 2015 and December 31st, 2017. The population consisted of patients aged 18 years or older with OHCA of presumed cardiac origin occurring in the catchment area of Saskatoon's EMS service. Variables of interest included, age, gender, First Nations status (as identified by treaty number), EMS response times, bystander CPR, and shockable rhythm. Outcomes of interest included return of spontaneous circulation (ROSC), survival to hospital admission, and survival to hospital discharge. Results: In all, 372 patients sustained OHCA, of which 27 were identified as First Nations. First Nations patients with OHCA tended to be significantly younger (mean age 46 years vs. 65 years, p < 0.0001) and had shorter EMS response times (median times 5.3 minutes vs. 6.2 minutes, p = 0.01). There were no differences between First Nations and non-First Nations patients in terms of incidence of shockable rhythms (24% vs. 26%, p = 0.80), ROSC (42% vs. 41%, p = 0.87), survival to admission (27% vs 33%, p = 0.53), and survival to hospital discharge (15% vs. 12%, p = 0.54). Conclusion: In Saskatoon, First Nations patients sustaining OHCA appear to have similar survival rates when compared with non-First Nations patients, suggesting similar baseline care. Interestingly, First Nations patients sustaining OHCA were significantly younger than their non-First Nations counterparts. This may reflect a higher burden of cardiovascular disease, suggesting a need improved prevention strategies.
Introduction: Our emergency department (ED) sees a low volume of high acuity pediatric cases. A needs assessment revealed that 68% of our Emergency Physicians (EP) manage pediatric patients in less than 25% of their shifts. The same percentage of EPs as well as ED nurses indicated they were uncomfortable managing a critically unwell neonate. Thus, an interprofessional curriculum focused on pediatric emergencies for ED staff was developed. In-situ simulation education was chosen as the most appropriate method to consolidate each didactic block of curriculum, and uncover important system gaps. Methods: Needs assessment conducted, and emerging themes informed IPE curriculum objectives. A committee of experts in simulation, pediatric emergencies and nursing education designed a full-day, RCPSC accredited, interprofessional in-situ simulation program. Results: Progressive segmental strategy maximized learning outcomes. The initial phase (2 hrs) comprised an” early recognition of sepsis” seminar and 4 rotating skills stations (equipment familiarity, sedating the child, IV starts, and mixing IV medication). This deliberate, adaptive, customized practice was enhanced by expert facilitation at each station, directly engaging participants and providing real-time feedback. The second phase allowed interprofessional teams of MDs, RNs and Physician Assistants to apply knowledge gained from the didactic and skills stations to in-situ simulated emergencies. Each group participated in two pediatric emergency scenarios. Scenarios ran 20 minutes, followed by a 40 minute debrief. Each scenario had a trained debriefer and content expert. The day concluded with a final debrief, attended by all participants. Formalized checklists assessed participants knowledge translation during simulation exercises. Participants assessed facilitators and evaluated the simulation day and curriculum via anonymous feedback forms. Debriefing sessions were scribed and knowledge gaps and system errors were recorded. Results were distributed to ED leaders and responsibilities assigned to key stakeholders to ensure accountability and improvement in system errors. Results All participants reported the experience to be relevant and helpful in their learning. All participants requested more frequent simulation days. System gaps identified included: use of metric vs imperial measurements, non-compatible laryngoscope equipment, inadequate identification of team personnel. As a result, the above-mentioned equipment has been replaced, and we are developing resuscitation room ID stickers for all team roles. Conclusion: Simulation as a culmination to a didactic curriculum provides a safe environment to translate acquired knowledge, increasing ED staff comfort and familiarity with rare pediatric cases. Additionally, is an excellent tool to reveal system gaps and allow us to fill these gaps to improve departmental functioning and safety.
Introduction/Innovation Concept: Estimates suggest that up to eighty-seven percent of human trafficking victims have come into contact with a healthcare provider during their exploitation and yet less than ten percent of emergency medicine (EM) physicians feel confident in identifying a victim. When provided with the relevant tools, medical personnel can aid in the recognition of victims and take the necessary steps in providing appropriate care when they present to the emergency department. Identifying this need for increased awareness in the urgent care setting, a module on human trafficking was implemented into the undergraduate medical education and departmental grand rounds. Methods: After identifying gaps in current medical education regarding screening for victims of human trafficking, a literature review was completed on the topic in medical education and utilized in constructing a list of objectives. These were then reviewed by community organizations that aid victims of trafficking and the Canadian Alliance of Medical Students Against Human Trafficking. Undergraduate medical students completed surveys prior to and following the learning module, in order to evaluate improvement in acquired knowledge. Curriculum, Tool, or Material: A one-hour lecture from ACT Alberta was given to undergraduate medical students as well as to residents and staff in departmental grand rounds. The session met the following objectives: defining human trafficking, recognition of victims, and identification of next steps in providing care. Additionally, an online module from Fraser Health was made available as an additional resource with case studies specific to emergency departments. The surveys consisted of 13 questions evaluating students’ knowledge on human trafficking and its prevalence in emergency medicine. The questions were a combination of a Likert scale, multiple choice, and short answer. There was a large amount of positive feedback from the students and comparison of the surveys showed that their knowledge in identifying victims had significantly improved. Conclusion: Medical students, residents, and staff may come into contact with victims of trafficking in the emergency department and yet less than three percent of emergency physicians have had training on how to recognize a victim. Implementing human trafficking awareness will impact EM medical education by providing victims a greater chance of being recognized and offered help when they present to the emergency room.
A new protocol for the quantitative determination of zeolite-group mineral compositions by electron probe microanalysis (wavelength-dispersive spectrometry) under ambient conditions, is presented. The method overcomes the most serious challenges for this mineral group, including new confidence in the fundamentally important Si-Al ratio. Development tests were undertaken on a set of natural zeolite candidate reference samples, representing the compositional extremes of Na, K, Cs, Mg, Ca, Sr and Ba zeolites, to demonstrate and assess the extent of beam interaction effects on each oxide component for each mineral. These tests highlight the variability and impact of component mobility due to beam interaction, and show that it can be minimized with recommended operating conditions of 15 kV, 2 nA, a defocused, 20 μm spot size, and element prioritizing with the spectrometer configuration. The protocol represents a pragmatic solution that works, but provides scope for additional optimization where required. Vital to the determination of high-quality results is the attention to careful preparations and the employment of strict criteria for data reduction and quality control, including the monitoring and removal of non-zeolitic contaminants from the data (mainly Fe and clay phases). Essential quality criteria include the zeolite-specific parameters of R value (Si/(Si + Al + Fe3+), the 'E%' charge-balance calculation, and the weight percent of non-hydrous total oxides. When these criteria are applied in conjunction with the recommended analytical operating conditions, excellent inter-batch reproducibility is demonstrated. Application of the method to zeolites with complex solid-solution compositions is effective, enabling more precise geochemical discrimination for occurrence-composition studies. Phase validation for the reference set was conducted satisfactorily with the use of X-ray diffraction and laser-ablation inductively-coupled plasma mass spectroscopy.
Introduction: Between 1980 and 2008, survival rates following an out-of-hospital cardiac arrest (OHCA) have remained unchanged, averaging 7.6%. Despite the use of new and emerging technologies, new medications, and automated external defibrillators, survival remains low. Recently, a new focus in cardiopulmonary resuscitation (CPR) has shown dramatic improvements in survival post OHCA. This new model, called pit-crew CPR, focuses on minimizing interruptions in chest compressions and has each team member playing a specific role in the resuscitation, akin to the pit-crew of a car race. Certain districts in the United States and Canada have adopted the pit-crew, or a similar, high quality, maximum time-on-chest CPR model, with much success. We aim to determine whether the pit-crew model of CPR improves survival following OHCA in Saskatoon, SK. Methods: In Saskatoon, EMS and Fire crews respond to OHCAs and have been exclusively using the pit-crew model of CPR since Jan 1st, 2015. This study is a before and after retrospective chart analysis, comparing two groups - pre and post implementation of the pit-crew CPR model. The primary outcome is survival to hospital discharge post OHCA. Secondary outcomes include survival to admission and any return of spontaneous circulation (as per the Utstein definition). The inclusion criteria are patients >18 years old with a witnessed OHCA of presumed cardiac origin who receive CPR by EMS/Fire within the Saskatoon Ambulance service (MD Ambulance) catchment area. Patients were excluded if the OHCA was unwitnessed, or if there was a presumed non-cardiac cause for the arrest, e.g. trauma. Results: In the pre-pit-crew model cohort, between Jan 1st, 2011 and Sept 31st, 2014, 455 OHCAs were analyzed. In this cohort 10.5% survived to discharge, 31.9% survived to admission and ROSC was achieved in 39% of cases. The percentage of patients with initial rhythms of VF/VT, asystole or PEA were 28.5% (26%), 41.5% (1%) and 23.6% (10%) respectively, with survival to discharge shown in parentheses. The post-pit-crew cohort is still in the data collection phase. Conclusion: Our pre-pit crew cohort data has been collected and analyzed. With ongoing data acquisition for the post-pit crew cohort, we hope to have the full data set complete by the end of 2018. It will be at that time when we are able to determine whether the pit-crew model of CPR improves survival to discharge following OHCA in Saskatoon.
We present the observed “continuum” levels of polarization as a function of time for four well-observed Type II-Plateau supernovae (SNe II-P; Fig. 1), the class of SNe decisively determined to arise from red supergiant stars (Smartt 2009). All four objects show temporally increasing degrees of polarization through the end of the photospheric phase, with some exhibiting early-time polarization that challenge existing models (e.g., Dessart and Hillier 2011) to reproduce. A fundamental ejecta asymmetry is present in this photometrically diverse sample of type II SNe, and it probably takes different forms (e.g., 56Ni blobs/fingers, large scale deformation). We acknowledge support from NSF grants AST-1009571 and AST-1210311.
Six samples of ‘Vermiculite’ have been studied to investigate the mechanism of its well known but poorly understood property to exfoliate. The samples were analysed quantitatively by XRD to determine their precise mineralogical composition. Electron microprobe methods, including elemental mapping of native potassium and of caesium (introduced by cation exchange) were used to examine variation in the chemical composition of the particles. Most of the samples examined show heterogeneous mineralogical compositions which occur as distinct zones within the volume of individual particles, presenting a mosaic texture. Exfoliation is related to this mosaic distribution of the different mineral phases within the particles. Lateral phase boundaries between vermiculite and mica layers, or vermiculite and chlorite layers are postulated to prevent or impede the escape of gas from a particle, resulting in exfoliation when the pressure exceeds the interlayer bonding forces that hold the layers together. This mechanism provides a common explanation for the exfoliation of ‘Vermiculite’ by thermal methods or by treatment with H2O2. Paradoxically, one sample which consists of pure vermiculite, in the mineralogical sense of the term, demonstrates that pure vermiculite does not and should not exhibit the property of exfoliation. Our explanation of the mechanism of exfoliation explains the commonly observed particle size dependence of exfoliation and the tendency for obviously poly-phase ‘Vermiculite’ samples to show the largest coefficients of expansion.
Cucullia umbratica Linnaeus (Lepidoptera: Noctuidae), Agnippe prunifoliella Chambers (Lepidoptera: Gelechiidae), and Bryotropha plantariella Tengstrom (Lepidoptera: Gelechiidae), were significant bycatch in pheromone-based trapping systems for red-striped fireworm, Aroga trialbamaculella Chambers (Lepidoptera: Gelechiidae), in Nova Scotia, Canada. Cucullia umbratica is a European introduced species and a new macrolepidopteran recorded in continental Canada. The only previous record of this moth in North America was from the Magdalen Islands (Québec, Canada). Potential attractants for B. plantariella, A. prunifoliella, and C. umbratica are a result of this bycatch investigation.
This paper presents time-averaged data for high-Reynolds-number hypersonic shock-wave/boundary-layer interactions, using a body of revolution to achieve high standards of two-dimensionality. The data are collected at nominal Mach 8.9, but a calibration is included that permits weak flow gradients in the test section to be incorporated as part of the data interpretation or flow modelling. The axisymmetric turbulent test boundary layer is developed on a hollow cylinder, aligned axially with the flow. The shock-wave interaction with this boundary layer is then generated by two separate configurations. Firstly, an impinging shock-wave case, that uses a concentric cowl to radiate an axisymmetric shock system onto the test boundary layer: for this case both an attached flow and a separated flow interaction are formed. Secondly, use of a conical-flare afterbody to produce a separated flow interaction. Quantitative data are presented for surface pressures and heat transfer, supported by some schlieren visualization and surface oil flows. A restricted CFD programme is included to assist the interpretation of the experiments.
Interstratified illite-smectite (I-S) occurring authigenically in diverse earth crust environments reacts toward more illite-rich phases as temperature increases. For that reason, I-S is used for geothermometry when prospecting for hydrocarbons or ore mineral deposits. This study develops the mathematical relations for characterizing the coherent stacking potential of fundamental particles (FP) using the expandability ratio K, where K is defined as (%SMAX –; %SXRD)/%SMAX. The ratio can be applied to differentiating I-S samples from shales, bentonites, and hydrothermal alterations. In particular, patterns on a K vs. T diagram, where T is the average thickness of fundamental particles (FPs), appear to be indicative of the geological conditions related to I-S formation. Shale samples plot in the negative K domain of the diagram, possibly due to the intimate mixing of detrital particles. Both bentonitic and hydrothermal samples display trends of increasing K with T, which suggests the coherent stacking potential progressively decreases as FPs increase in thickness. Hydrothermal samples are more extensively distributed on the diagram than samples from bentonites. This result may reflect differences in particle growth conditions (nutrients and space) between bentonites (short supply) and hydrothermal alterations (good supply).
The purpose of this study was to DNA fingerprint the majority (64 %) of isolates received at the Pertussis Reference Laboratory during the 1993 whooping cough epidemic by pulsed field gel electrophoresis of Xba I - generated restriction digests. Two DNA restriction patterns, types 1 and 3, predominated (40% and 23%. respectively, of 180 isolates) but type 2, identified in a previous study was notably absent. Twenty-one new DNA types occurred (24% of isolates), some being atypical as bands 155–230 kb were no longer conserved, but there was no statistically significant difference in their incidence in the upswing (June-September) compared to the downswing (October-December) phase of the epidemic. There was a relatively high proportion of new types, compared to type 1. at the peak (September). About 50% of isolates received were from the North Western Region, where 44% of isolates were DNA type 1. Whereas only 1 out of 10 isolates from Scotland were of this type, suggesting some geographic variation. Statistically significant findings included a higher proportion of isolates from female patients (P < 0·01), most marked in the 12–24 months age group (P < 0·05); a higher proportion of infants under 12 months requiring hospital admission compared to older children (P < 0·05); and a greater number of isolates from unvaccinated children (P < 0·01). Analysis of serotype according to four age groups (under 3 months, 3–12 months, 12–24 months and above 2 years) showed statistically significant differences (P < 0·05) with a noticeably lower proportion (38%) of serotype 1,3 in 3–12 months age group and higher prevalence (74%) of serotype 1,3 in the 12–24 months age group. There was no correlation between DNA type and serotype.
Vermiculite minerals are locally available in the Mozambique Belt of Tanzania but are not currently commercially exploited. In part this may be due to lack of any precise characterization. This study was carried out as a first step to assess the suitability of these vermiculites for crop production by characterization of their mineralogical and chemical compositions. X-ray diffraction and scanning electron microscopy combined with an energy-dispersive X-ray system were used to establish the mineralogy. Electron microprobe analysis and inductively coupled plasma-mass spectrometry were used to study the chemical compositions and to identify any possible issues related to chemical composition that might affect their use if applied as soil conditioners. The samples were characterized as vermiculites and hydrobiotites with a wide variety of accessory minerals. Accessory minerals that might be of some concern are galena, fibrous amphiboles and sepiolite. The total levels of Ni in all vermiculites, and Cr in some, were also found to be high relative to common European standards and this might limit their potential as soil conditioners. It is clear that a field assessment of the bioavailability of various elements would be necessary before decisions relating to potential agricultural use could be made.
Respirable forms of crystalline silica including the mineral cristobalite are known carcinogens and the subject of increasing regulation and codes of good practice. Some bentonites may contain cristobalite, but more commonly they contain opal-CT, or opal-C, which can be confused with cristobalite. In the light of increasing regulation there is a clear need for simple and reliable methods that can distinguish cristobalite from the opals in bentonites and other clay materials. Here we propose the use of a simple NaOH method that is easily applied to bulk samples of bentonites. The method consists of boiling the clay in 0.5 M NaOH for 10 min and measuring the weight of undissolved solid. The method is shown to be accurate for both the identification and quantification of opal in bentonites since these phases are soluble when thus treated. It is also a straightforward method to distinguish the opals from cristobalite as the latter is essentially insoluble. Adoption by industry of a simple operationally-defined method such as this would be preferable to ad hoc reliance on direct instrumental methods alone such as X-ray powder diffraction, as the latter almost always require a large element of judgement and experience on the part of the analyst, although direct methods do need to be used in a supporting role.
The population of Saturn's outermost tenuous E-ring is dominated by tiny water ice particles, some of which contain organic or mineral impurities. Active cryo-volcanism on the moon Enceladus, embedded in the E-ring, has been known to be a major source of particles replenishing the ring since late 2005. Therefore, particles in the vicinity of Enceladus provide crucial information about the dynamic and chemical processes occurring far below the moon's icy surface.
We present a compositional analysis of thousands of impact ionisation mass spectra of Saturn's E-ring particles, with sizes predominantly below 1 μm, detected by the Cosmic Dust Analyser onboard the Cassini spacecraft. Our findings imply that organic compounds are a significant component of icy particles ejected by Enceladus plumes. Our in situ measurements are supported by detections of other Cassini instruments. They hint at a dynamic interaction of a hot rocky core with liquid water below the icy surface, where the organic molecules are generated. Further insights are expected from two close Enceladus flybys to be performed by Cassini in 2008. Then, for the first time, we will obtain spectra of freshly ejected particles at the traversals through the cryo-volcanic plumes.
We present results of two studies aiming at better understanding the properties of massive stars in the Galactic Center. We focus on the youngest and oldest of the three massive clusters harboring this region, namely the Arches and central cluster. We show that the development of powerful observational techniques in the near infrared spectral range (mainly 3D spectroscopy) allows to uncover the entire massive star population in these clusters. Using CMFGEN models, we derive the classical stellar and wind properties of 46 stars, as well as their surface abundances. The latter allow us to investigate in detail their evolutionary status and to identify evolutionary sequences between different types of stars. We thus constrain stellar evolution in the upper part of the HR diagram.