The main objectives for this study are: 1. To investigate novel, non-invasive ocular measurements including optical coherence tomography and eye tracking in a cross-sectional study of participants with various neurodegenerative dementias against standard cognitive assessments and brain imaging measures; and 2. To assess the potential utility of ocular assessments for early detection in the pre-dementia, i.e. the so-called Mild Cognitive Impairment (MCI) stage, across the common neurodegenerative dementia syndromes and, Vascular Cognitive Impairment (VCI) due to small vessel disease (SVD). 3. To determine the prevalence and relevance of amyloid uptake on PET scanning across the dementias most commonly associated with amyloidosis. Specifically we aim to examine correlations with amyloid uptake status in patients symptomatic from the most common proteinopathies (ie amyloid, tau, synuclein) combined in varying degrees with the most common vasculopathies (ie small vessel disease) using multimodal structural and functional imaging, cognitive behavioral, and gait and balance measures, taking into account genetic risk markers (particularly apolipoprotein E genotypes) and fluid biomarkers ( eg cytokines, oxidative stress, lipidomics).

The aim of the study is to show that rapid, simple targeted radiotherapy to brain metastases with 8 Gy / 1 is non-inferior to 20 Gy / 5 in terms of overall survival for patients with poor prognosis.

Standard Heparin management, based on total body weight, is not well established for obese patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). The purpose of this study is to assess the safety and efficacy of using lean body mass (LBM) to determine pump flow rate and/or Heparin dosage in obese patients undergoing CPB.

Obsessive-compulsive disorder (OCD) is a severe and debilitating anxiety disorder afflicting about 2% of the population. It is characterized by the presence of recurrent obsessions and/or compulsions that are time consuming and cause marked distress and/or impairment. Untreated, OCD runs a chronic and deteriorating course. According to the World Health Organization, OCD is among the top 10 leading causes of disability worldwide. Examination of non-medicinal treatments for OCD has focused on two distinct treatments: exposure and response prevention (ERP) and cognitive therapy (CT), often combined into an integrated cognitive-behavioural treatment (CBT). CBT is considered the first line psychological treatment for OCD, with estimates of response rates of between 70-80%. However, there are a significant number of treatment non-responders and the majority of responders are still left with impairing residual symptoms. One area of investigation that has shown potential benefit for general mood and anxiety disorders has been mindfulness-based interventions (MBIs), yet the potential benefits of MBIs in OCD has been largely unexamined, except for several small preliminary studies that show clinical promise. The purpose of this study is to examine the clinical benefits of a standardized MBI treatment for OCD in a large-scale, multi-site randomized controlled trial. The results of this study will directly determine whether Mindfulness can be considered an effective treatment for OCD. If this study can demonstrate that a short-term mindfulness intervention can significantly reduce the suffering associated with OCD, then the findings could easily be translated into routine clinical care in and out of hospital settings. Results of this study will also potentially add to our understanding of the mechanisms that drive OCD symptoms, improve our knowledge of psychological treatment mechanisms, and elucidate how biological factors influence psychological treatment outcomes.

Atrial fibrillation (AF) is a type of irregular heart rhythm due to electrical signal disturbances of the heart. It is a very common arrhythmia and the risk of developing AF increases with age and with other risk factors such as diabetes, high blood pressure, and underlying heart disease. The main complications of AF are heart failure and stroke. However, studies have shown that restoration of normal rhythm does not reduce these complications. Rather, these complications are mitigated by controlling the heart rate and using blood thinners to prevent stroke. Symptoms secondary to AF can occur due to the irregular heart rate and poor contraction in the atria, the top chambers of the heart. These symptoms include shortness of breath, fatigue, reduced exercise tolerance, and palpitations. Restoring sinus rhythm can sometimes alleviate these symptoms. Given that studies to date have not shown a difference in hard clinical endpoints between rate and rhythm control strategies, the decision to proceed with rhythm control depends on the patient symptom burden. Rhythm control strategies in patients with persistent AF include cardioversion back to sinus rhythm with long-term recurrence prevention via anti-arrhythmic drugs (AADs) or catheter ablation. However, many studies of these procedures omit a sham placebo control arm. No atrial fibrillation procedural intervention has been compared to a sham procedure. The cardioversion procedure can easily be compared to a "sham" alternative, as it is non-invasive with an expected response within days-to-weeks. Thus, a cardioversion versus "sham" cardioversion trial will allow us to truly assess the impact of a rhythm-control strategy on QOL. It is hypothesized that cardioversion of atrial fibrillation leads to significant improvement in quality of life (QOL) compared to sham cardioversion. Understanding the true QOL impact of sinus rhythm restoration in patients with persistent AF is of significant importance in guiding strategies for the management of AF. Hence, by evaluating what the true effect of cardioversion on QOL in this blinded study, we can better understand the role of medical management and AF ablation in our patients and assess resource allocation to these procedures.

This Phase 1/2a multiple part study is a first time-in-human (FTIH) study designed to evaluate the safety, tolerability, and pharmacokinetics (PK) of single (Part 1) and repeat doses (Part 2) of GSK3965193 in healthy participants. Part 3 will evaluate the ability of GSK3965193 to lower hepatitis B virus surface antigen (HBsAg) in participants living with chronic hepatitis B infection (PLWCHB) and will be given the option to subsequently receive treatment with open label bepirovirsen. Part 4 will evaluate the safety and tolerability of combination therapy with GSK3965193 and bepirovirsen and the potential to effect sustained virologic response in PLWCHB.

The goal of this observational study is to learn about the amount and types of anesthesia wastes generated for each surgical case at the Toronto Western Hospital (TWH). The main questions it aims to answer are: * The amount of anesthesia waste generated per surgical case at TWH * The amount of wastes that are inappropriately discarded * The percentage of discarded waste that can be reused or recycled * The percentage of recyclable waste that is actually recycled * The percentage of discarded waste that is appropriately sent to landfill * The financial cost of waste disposal * The impact of a staff education program on waste reduction and proper waste disposal The research team will conduct the audit by inspecting the contents of the waste bins and bags following completion of a surgery.

Mechanical ventilation is frequently used in the operating room and the intensive care settings. Although essential in many cases, mechanical ventilation can be responsible for ventilator-induced lung injury (VILI). The relationship between mechanical ventilation and VILI has been clearly demonstrated in animals and is highly suspected in humans. The putative mechanism responsible for VILI is excessive pulmonary strain or overdistension. Frequently observed in mechanically ventilated patients, the presence of a severe pre-existing pulmonary disease can increase the risk of overdistension. The development of a tool allowing early detection of pulmonary overdistension would represent a great asset in the prevention of VILI by allowing safer adjustments of mechanical ventilation parameters. Ultrasonographic imaging is a non-radiant, non-invasive technique already available in the intensive care setting. Already used for cardiac strain measurements, ultrasonography is a promising avenue to assess pulmonary strain.This study will aim to establish normal pleural strain values using ultrasonography in healthy volunteers. Purpose: The primary objective is to calculate 95% confidence intervals in pleural strain for a set of 8 inspired volumes at 15 predetermined lung areas in healthy volunteers. The secondary objectives of the study are: * to modelize the relation between pleural strain and inspired volume * to modelize the relation between pleural strain and global pulmonary volumetric strain * to modelize the relation between pleural strain and maximal echo intensity change * to compare the regional distribution pattern of pleural strain in healthy volunteers in dependent versus non-dependent areas. Hypothesis: Elastography using the Lagrangian speckle model estimator based on optical flow allows the determination of normal mean values and 95% confidence intervals of pleural strain (average Von Mises coefficient) in 15 predetermined lung areas for a set of 8 inspired volumes in healthy volunteers.

This is a feasibility and pilot study. Though large-scale online neurocognitive testing is increasingly being done in psychiatry, there are no such efforts in Parkinson's research. Thus a large part of this pilot study will be to demonstrate feasibility and reliability, and use this experience to develop a feasible protocol for ongoing research. The specific short-term objectives are: 1. To establish the feasibility of performing large-scale deep cognitive phenotyping using online cognitive testing. 2. To demonstrate that online neurocognitive testing is valid and reliable in a smaller sample of locally recruited participants tested both in-lab and online.

The investigators will assess the efficacy of clinically recommended counterpressure maneuvers (CPM) in preventing syncope for paediatric patients. Participants presenting to the emergency department (ED) will first provide written informed consent. In stage I, they will be asked to complete a brief survey documenting the presentation of their syncopal episode, and any prodromal symptoms they experienced. Participants that consent to the second stage of the study will either receive usual care (control arm) or training in counter pressure maneuvers alongside usual care (intervention arm; leg crossing, bending, arm tensing). These patients will be followed for one years time, and will be asked to complete monthly surveys detailing their syncopal and presyncopal recurrence. Medical records will be accessed over the duration of the study to identify any changes in medical diagnosis.