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Prenatal exposure to persistent organic pollutants (POPs) has been associated with the development of metabolic syndrome-related diseases in offspring. According to epidemiological studies, father’s transmission of environmental effects in addition to mother’s can influence offspring health. Moreover, maternal prenatal dietary folic acid (FA) may beneficially impact offspring health. The objective is to investigate whether prenatal FA supplementation can overcome the deleterious effects of prenatal exposure to POPs on lipid homeostasis and inflammation in three generations of male rat descendants through the paternal lineage. Female Sprague-Dawley rats (F0) were exposed to a POPs mixture (or corn oil) +/− FA supplementation for 9 weeks before and during gestation. F1 and F2 males were mated with untreated females. Plasma and hepatic lipids were measured in F1, F2, and F3 males after 12-h fast. Gene expression of inflammatory cytokines was determined by qPCR in epididymal adipose tissue. In F1 males, prenatal POPs exposure increased plasma lipids at 14 weeks old and hepatic lipids at 28 weeks old and prenatal FA supplementation decreased plasma total cholesterol at 14 weeks old. Prenatal POPs exposure decreased plasma triglycerides at 14 weeks old in F2 males. No change was observed in inflammatory markers. Our results show an impact of the paternal lineage on lipid homeostasis in rats up to the F2 male generation. FA supplementation of the F0 diet, regardless of POPs exposure, lowered plasma cholesterol in F1 males but failed to attenuate the deleterious effects of prenatal POPs exposure on plasma and hepatic lipids in F1 males.
Information retrieval (IR) aims at retrieving documents that are most relevant to a query provided by a user. Traditional techniques rely mostly on syntactic methods. In some cases, however, links at a deeper semantic level must be considered. In this paper, we explore a type of IR task in which documents describe sequences of events, and queries are about the state of the world after such events. In this context, successfully matching documents and query requires considering the events’ possibly implicit uncertain effects and side effects. We begin by analyzing the problem, then propose an action language-based formalization, and finally automate the corresponding IR task using answer set programming.
Cette étude visait à identifier les facilitateurs, les obstacles et la faisabilité d’implanter un Accompagnement-citoyen personnalisé d’intégration communautaire (APIC) pour des aînés en perte d’autonomie et vivant dans la communauté. L’APIC est un suivi hebdomadaire de trois heures réalisé par un accompagnateur non professionnel formé et supervisé qui vise à optimiser la réalisation d’activités sociales et de loisirs de personnes ayant des incapacités. Une recherche-action a permis de réaliser des entretiens semi-dirigés auprès de 16 participants de la communauté. Les principaux facilitateurs de l’implantation sont l’adaptabilité de l’APIC et son appui scientifique, la reconnaissance d’un besoin, l’expertise et la collaboration. La présence de leaders ouverts à la nouveauté et d’individus offrant du soutien est favorable. Le financement de l’implantation, associé à un contexte économique défavorable, est un obstacle. La majorité des participants perçoivent qu’il serait faisable d’implanter l’APIC en l’intégrant à des structures bénévoles déjà existantes. Ces connaissances permettront d’optimiser l’implantation de l’APIC ou d’interventions similaires dans la communauté.
Psychosurgery refers to the surgical interruption of the white matter fibres joining the frontal cortex to the remainder of the cortical mantle and to the thalamus, in an attempt to mitigate the manifestations of psychosis. It reached its heyday following World War Two and was abandoned with the introduction of major tranquilisers such as chlorpromazine. Wilder Penfield, unlike most of his contemporaries, had a jaundiced view of psychosurgery. This paper addresses Penfield’s early experience with experimental, penetrating brain trauma and with the surgical resection of frontal, epileptogenic lesions, which explain his antagonism towards psychosurgery.
Introduction: Royal College Emergency Medicine (EM) trainees at the University of Ottawa participate in weekly Academic Full Days (AFD) that consist of didactic activities, simulation-based learning, and core content sessions referred to as Core Rounds (CR). Despite CR being intentioned for all EM trainees, an attendance attrition has been noted as trainees progress towards their senior (SR) years (PGY3-5). The objectives of this study were to (1) identify barriers to SR trainee CR attendance and (2) identify areas for CR improvement. Methods: An on-line survey was administered to SR EM trainees (PGY3-5, n = 28) and recent graduates from our program (practice year 1-2, n = 20) to explore perceptions of the value of AFDs, CR attendance barriers, and areas for CR improvement. The survey consisted of 5-point Likert scales and free-text responses. Quantitative responses were analyzed using Microsoft Excel. Free-text responses were analyzed qualitatively using thematic analysis. Each free-text response was reviewed independently by two investigators (JML, MCL) and underwent line-by-line coding. Through joint discussions, the codes from each response were synthesized and themes were identified. Results: Of the 48 trainees and attendings surveyed, 32 responded (response rate 67%). Most respondents (90%) stated they benefited from SR trainee attendance when they were at a junior (JR) level. The majority perceived they benefited less from CR as a SR trainee compared to when they were a JR trainee (85%). Further, 87% responded that CR were not tailored to a SR level, and that they would attend more frequently if sessions were geared to their level (81%). From our thematic analysis, three themes emerged relating to SR trainee absenteeism: 1) CR quality, 2) External Factors (eg. trainee fatigue) and 3) Malalignment with trainees’ own education plan. We also identified three themes relating to areas for CR improvement: 1) CR content, 2) CR format and 3) SR trainee involvement. Conclusion: Respondents indicated a benefit to having SR trainee presence at CR. This study identified barriers to SR resident attendance at CR and areas for improvement. With the transition to competency based medical education it is critical that trainees engage in effective educational experiences, especially as the RCPSC does not mandate AFDs for EM training in this new curriculum. A culture-change initiative and CR reformat is now underway at our institution with planned post-implementation analysis.
Psychosocial needs related to disaster are increasingly identified as a significant concern for both communities and responders. In response to the needs of travelers suddenly unable to leave Vancouver immediately after 9/11 in the United States, a network for the provision of volunteer mental health response at the time of a disaster was developed through the Provincial government within British Columbia (BC). Starting from less than 20 individuals primarily located within the Vancouver area, Disaster Psychosocial Services (DPS) now encompasses a network of over approximately 200 providers throughout the Province.
To showcase a successfully functioning DPS program modeled after a volunteer-based mental health network, the evolution undergone, its present operational framework, and future goals.
In response to the observed need for trained psychosocial intervention, we developed a framework for recruitment, education, deployment, and support of a volunteer network of mental health professional and paraprofessional providers.
This approach has been found to be effective, significantly increasing our volunteer base and opportunities for deployment.
This presentation will detail the grassroots development of BC’s DPS Program as well as the current model in practice. It will provide an overview of how BC’s DPS network of providers was stimulated and managed; issues related to volunteer management, including the selection of volunteers; methods of specialized training; and deployment. Multiple settings in which DPS is now utilized with increasing regularity will be described, including Emergency Operations Centers, Reception Centers, and Town Hall Meetings. Lastly, there will be a focus on the lessons learned, as well as future goals highlighting a focus on culturally-sensitive support, specifically with respect to British Columbia’s indigenous populations for building community resiliency and knowledge across the province.
Innovation Concept: Ventilator management is an essential skill and a training objective for emergency medicine (EM) specialists in Canada. EM trainees obtain the majority of this training during off-service rotations. Previous attempts to strengthen ventilator knowledge include lectures and simulation – both of which are time and resource intensive. Given the unique features of ventilator management in the ED, we developed an ED-specific ventilator curriculum. The purpose of this study is to 1) identify resident needs regarding ventilator curricula and 2) assess resident response to this pilot curriculum. Methods: A needs-assessment survey administered to RCPSC- and CCFP-EM residents at The Ottawa Hospital (TOH) showed the majority of residents (87%, n = 31 respondents) believe there is a need for more ED-focused ventilator management training, and only 13% felt confident in ventilator management. Ten on-line modules were prepared by an EM-Critical Care attending, and distributed on-line to all EM trainees at TOH (n = 52). Mid- and post-implementation surveys are used to assess residents’ confidence in ventilator management, and perceived usefulness of the curriculum. User feedback from focus groups constitutes part of the curriculum evaluation. Curriculum, Tool or Material: Employing a flipped classroom approach, ten on-line modules were distributed to RCPSC- and CCFP-EM trainees at TOH. Each module requires less than ten minutes to complete and focuses on a single aspect of ventilation. The modules are available for residents to complete at their own pace and convenience. At curriculum completion, an EM-Critical Care attending physician facilitates an interactive session. Conclusion: Mid-implementation survey results demonstrate increased confidence in independently managing ventilated patients in the ED (13% pre- vs. 56% mid-implementation), and an increased perception of having sufficient ventilator training (26% pre- vs. 78% mid-implementation). All respondents felt the modules were of appropriate length, content was easy to follow, and that the modules should be part of the residency curriculum. Our ED-specific online ventilator modules area a viable tool to increase residents’ confidence in ventilator management. This novel curriculum could be adopted by other residency programs and continuing professional development initiatives. Future work will include post-implementation data-gathering, and formal curriculum evaluation.
All intensity data in a powder XRD pattern can be used to provide useful results for the interpretation of the mineralogical variability of geological samples. Simple statistical methods using Bonferroni's theorem permit the recognition of areas usually associated with mineral peaks where sample patterns are different at a predetermined level of confidence. Intensity/frequency histograms reveal subtle differences in low intensity regions of the XRD patterns that are also indicative of sample variability. These procedures facilitate the comparison of samples and may reduce the total analytical error because the weight percent determination can be eliminated.
The purpose of this paper is to show that most results concerning polyadic algebras can be generalized to transformation algebras. The results of this paper will clearly indicate that a great deal can be done in polyadic algebras without ever mentioning the quantifier structure (for instance, terms and operations can be characterized without the help of the quantifier structure, at least in the case where an equality is present). In § 1, we develop the elementary theory; in § 2, we study the different ways of extending a (locally finite) transformation algebra (of infinite degree) to a polyadic algebra; in § 3, we study equality transformation algebras; finally, in § 4, we show how terms and operations can be defined in equality transformation algebras.
Introduction. This paper concerns the problem of extending a given measure defined on a Boolean ring to a measure on the generated σ-ring. Two general methods are familiar to the literature, that of Lebesgue (outer measure) and a method proposed by Borel using transfinite induction (4, 49-134; 2, 228-238).
Traditional manufacturing methods restrict the expansion of thermoelectric technology. Here, we demonstrate a new manufacturing approach for thermoelectric materials. Selective laser melting, an additive manufacturing technique, is performed on loose thermoelectric powders for the first time. Layer-by-layer construction is realized with bismuth telluride, Bi2Te3, and an 88% relative density was achieved. Scanning electron microscopy results suggest good fusion between each layer although multiple pores exist within the melted region. X-ray diffraction results confirm that the Bi2Te3 crystal structure is preserved after laser melting. Temperature-dependent absolute Seebeck coefficient, electrical conductivity, specific heat, thermal diffusivity, thermal conductivity, and dimensionless thermoelectric figure of merit ZT are characterized up to 500 °C, and the bulk thermoelectric material produced by this technique has comparable thermoelectric and electrical properties to those fabricated from traditional methods. The method shown here may be applicable to other thermoelectric materials and offers a novel manufacturing approach for thermoelectric devices.
JC virus is the etiological agent of progressive multifocal leukoencephalopathy, a white matter demyelinating disease that mostly affects immunocompromised patients. JC virus can also infect neurons and meningeal cells and cause encephalitis, meningitis and granule cell neuronopathy. We report a patient with JC virus granule cell neuronopathy, without concomitant progressive multifocal leukoencephalopathy, presenting as inaugural acquired immune deficiency syndrome-related illness. This patient’s human immunodeficiency virus infection remained undiagnosed for several months after neurological symptoms onset. We review JC virus pathophysiology, clinical manifestations, treatment and prognosis, and emphasize the importance of considering human immunodeficiency virus infection and related opportunistic infections in the differential diagnosis of new-onset isolated cerebellar disease.
It remains unclear whether ST-elevation myocardial infarction (STEMI) patients transported by ambulance over long distances are at risk for clinical adverse events. We sought to determine the frequency of clinical adverse events in a rural population of STEMI patients and to evaluate the impact of transport time on the occurrence of these events in the presence of basic life support paramedics.
We performed a health records review of 880 consecutive STEMI patients transported to a percutaneous coronary intervention centre. Patients had continuous electrocardiogram and vital sign monitoring during transport. A classification of clinically important and minor adverse events was established based on a literature search and expert consensus. A multivariate ordinal logistic regression model was used to study the association between transport time (0-14, 15-29, ≥30 minutes) and the occurrence of overall clinical adverse events.
Clinically important and minor events were experienced by 18.5% and 12.2% of STEMI patients, respectively. The most frequent clinically important events observed were severe hypotension (6.1%) and ventricular tachycardia/ventricular fibrillation (5.1%). Transport time was not associated with a higher risk of experiencing clinical adverse events (p=0.19), but advanced age was associated with adverse events (p=0.03). No deaths were recorded during prehospital transport.
In our study of rural STEMI patients, clinical adverse events were common (30.7%). However, transport time was not associated with the occurrence of adverse clinical events in these patients.
Glioblastomas (GBMs) account for nearly half of all primary malignant brain tumours, and current therapies are often only marginally effective. Our understanding of the underlying biology of these tumours and the development of new therapies have been complicated in part by widespread inter- and intratumoural heterogeneity. To characterize this heterogeneity, we performed regional subsampling of primary glioblastomas and derived organoids from these tissue samples. We then performed single-cell RNA-sequencing (scRNA-seq) on these primary regional subsamples and 1-3 matched organoids per sample. We have profiled samples from six tumour sets to date and have obtained sequencing data for 21,234 primary tissue cells and 14,742 organoid cells. While the most apparent differences in gene expression appear to be between individual tumours, we were also able to identify similar cellular subpopulations across tissue samples and across organoids. Importantly, organoids derived from the same tissue sample appeared to be composed of similar cellular subpopulations and were highly comparable to each other, indicating that replicate organoids faithfully represent the original tumour tissue. Overall, our scRNA-seq approach will help evaluate the utility of tumour-derived organoids as model systems for GBM and will aid in identifying cellular subpopulations defined by gene expression patterns, both in primary GBM regional subsamples and their associated organoids. These analyses will allow for the characterization of clonal or subclonal populations that are likely to respond to different therapeutic approaches and may also uncover novel therapeutic targets previously unrevealed through bulk analyses.
Introduction: Screening for organ and tissue donation is an essential skill for emergency physicians. In 2015, 4564 individuals were on a waiting list for organ transplant and 242 died while waiting. As Canadas donation rates are less than half that of other comparable countries, it is crucial to ensure we are identifying all potential donors. Patients deceased from poisoning are a source that may not be considered for referral as often as those who die from other causes. This study aims to identify if patients dying from poisoning represent an under-referred group and determine what physician characteristics influence referral decisions. Methods: In this cross-sectional unidirectional survey study, physician members of the Canadian Association of Emergency Physicians were invited to participate. Participants were presented with 20 organ donation scenarios that included poisoned and non-poisoned deaths, as well as one ideal scenario for organ or tissue donation used for comparison. Participants were unaware of the objective to explore donation in the context of poisoning deaths. Following the organ donation scenarios, a range of follow-up questions and demographics were included to explore factors influencing the decision to refer or not refer for organ or tissue donation. Results were reported descriptively and associations between physician characteristics and decisions to refer were assessed using odds ratios and 95% confidence intervals. Results: 208/2058 (10.1%) physicians participated. 25% did not refer in scenarios involving a drug overdose (n=71). Specific poisonings commonly triggering the decision to not refer included palliative care medications (n=34, 18%), acetaminophen (n=42, 22%), chemical exposure (n=48, 27%) and organophosphates (n=87, 48%). Factors associated with an increased likelihood to refer potential donors following overdose included previous organ and tissue donation training (OR=2.6), having referred in the past (OR=4.3), available donation support (OR=3.9), greater than 10 years of service (OR=2.1), large urban center (OR=3.8), holding emergency medicine certification (OR=3.6), male gender (OR=2.2, CI), and having indicated a desire to be a donor on government identification (OR=5.8). Conclusion: Scenarios involving drug overdoses were associated with under-referral for organ and tissue donation. As poisoning is not a contraindication for referral, this represents a potential source of donors. By examining characteristics that put clinicians at risk for under-referral of organ or tissue donors, becoming aware of potential biases, improving transplant knowledge bases, and implementing support and training programs for the organ and tissue donation processes, we have the opportunity to improve these rates and reduce morbidity and mortality for Canadians requiring organ or tissue donation.
Introduction: Stress has been shown to impair performance during acute events. The goal of this pilot study was to investigate the effects of two simulation-based training interventions and baseline demographics (gender, age) on stress responses to simulated trauma scenarios. Methods: Sixteen (16) Emergency Medicine and Surgery residents were randomly assigned to one of two groups: Stress Inoculation Training (SIT) or Crisis Resource Management (CRM). Residents served as trauma team leaders in simulated trauma scenarios pre and post intervention. CRM training focused on non-technical skills required for effective teamwork. The SIT group focused on cognitive reappraisal, breathing and mental rehearsal. Training lasted 3 hours, involving brief didactic sessions and practice scenarios with debriefing focused on either CRM or SIT. Stress responses were measured with the State Trait Anxiety Inventory (anxiety), cognitive appraisal (degree to which a person interprets a situation as a threat or challenge) and salivary cortisol levels. Results: Because the pre-intervention stress responses were different between the two groups, the results were analyzed with stepwise regression analyses. The only significant predictor of anxiety and cortisol responses were the residents appraisal responses to that scenario, explaining 31% of the variance in anxiety and cortisol. Appraisals of the post-intervention scenarios were predicted by their appraisals of the pre-intervention scenario and gender, explaining 73% of the variance. Men were more likely than women to appraise the scenarios as threatening. There were no differences in subjective anxiety, cognitive appraisal or salivary cortisol responses as a result of either intervention. Conclusion: Male residents, as well as those who appraised an initial simulated trauma scenario as threatening, were more likely to interpret a subsequent scenario as threatening, and were more likely to have larger subjective (anxiety) and physiological (cortisol) responses a subsequent scenario. Both CRM and SIT training were not effective in overcoming initial appraisals of potentially stressful events.
Introduction: Studies suggest that there is a significant discrepancy between emergency physicians diagnosis of TIA and confirmation by neurologists. The objectives of our study were to identify factors associated with neurologists confirmation of TIA in patients referred from the emergency department. Methods: Data were obtained from a prospective cohort study across more than 8 university-affiliated Canadian hospitals from 2006-2017 of adult patients diagnosed with a TIA or non-disabling stroke in the ED. Patients presenting after 1 week of symptom onset, receiving TPA as part of a stroke code, with a GCS<15 at baseline, and without a neurology assessment within 90 days were excluded. Univariate analyses were performed with t-tests or chi-square tests as indicated. Multivariate analysis with backward elimination was performed to identify unique predictors of TIA confirmation. Results: Of 8,669 patients diagnosed with TIA in the ED, 7,836 (90%) were assessed by neurology. The mean age of patients was 68.2 years and 71.1% presented with their first ever TIA. The rate of confirmation of TIA by neurology was 56%. The most common alternate diagnoses included migraines (26%), peripheral vertigo (10%), syncope (6%), and seizure (4%). The 3 strongest predictors of confirmation of TIA were infarct on imaging (OR 2.31, 2.03-2.63), history of weakness (OR 2.19, 1.95-2.48), and history of language disturbance (OR 2.05, 1.79-2.34). The 3 strongest predictors of an alternate diagnosis were syncope (OR 0.51, 0.39-0.67), history of bilateral weakness (or 0.51, 0.31-0.84), and confusion (OR 0.57, 0.48-0.67). Conclusion: The rate of TIA confirmation by neurology in our study was 56%. Emergency physicians should have a high index of suspicion of TIA in patients with history of weakness and language disturbance, and should resist referring to a stroke prevention clinic, patients with syncope, bilateral findings, or confusion.