University of Ottawa
  • Ottawa, ON, Canada
Recent publications
We consider the problem of learning a neural network classifier. Under the information bottleneck (IB) principle, we associate with this classification problem a representation learning problem, which we call “IB learning”. We show that IB learning is, in fact, equivalent to a special class of the quantization problem. The classical results in rate-distortion theory then suggest that IB learning can benefit from a “vector quantization” approach, namely, simultaneously learning the representations of multiple input objects. Such an approach assisted with some variational techniques, result in a novel learning framework, “Aggregated Learning”, for classification with neural network models. In this framework, several objects are jointly classified by a single neural network. The effectiveness of this framework is verified through extensive experiments on standard image recognition and text classification tasks.
This article examines the possibilities engendered by land-based analyses within the sociology of sport. We examine how “Canada’s” Truth and Reconciliation Commission’s calls to action on sport reproduce a logic of social inclusion, one which assimilates Indigenous athletes and Peoples into settler models of sport. To consider epistemological tools for unsettling settler sport systems, we turn to critical Indigenous scholarship on land-based analyses and pedagogies. To illustrate the possibilities of land-based analyses, we examine lacrosse, an Indigenous sporting practice with roots embedded in relational interconnectedness with the land. A land-based approach to sport offers opportunities for revising the assumptions, values, and ethics underpinning settler models of sport through, for example, emphasizing the importance of community, healing, and land stewardship.
In previous research, Canadian physiotherapists identified barriers to effective external focus promotion and recommended the delivery of a focus of attention workshop as a solution. Accordingly, the current research entailed the virtual delivery of such a workshop, consisting of asynchronous Website modules followed by a synchronous group session, to 15 Canadian physiotherapists working mainly with musculoskeletal rehabilitation clients. Assessment of the workshop outcomes was guided by constructs of social cognitive and adult learning theory, and organized based on the four levels of the Kirkpatrick model (KP1-Reaction, KP2-Learning, KP3-Behavior, and KP4-Results). Specifically, participants received links to questionnaire packages at three time points: 1-week preworkshop, immediately postworkshop, and 1-week postworkshop. Results showed that participants (a) reported high satisfaction, engagement, and perceived relevance of the workshop (KP1); (b) experienced significant improvements to their knowledge, skills, attitudes, and self-efficacy from pre- to immediately postworkshop (KP2); and (c) self-reported increases to their external focus promotion in the week following the workshop (modified KP3), and perceived improvements to their clients’ outcomes as a result of this external focus encouragement (modified KP4). Taken together, these results serve as a chain of evidence supporting the usefulness of the workshop in translating focus of attention findings into Canadian physiotherapy.
Advanced driver assistance systems (ADAS) are transforming the modern driving experience. Today’s vehicles seem better equipped than ever to augment safety by automating routine driving activities. The assumption appears straightforward: automation will necessarily improve road safety because automation replaces the human driver, thereby reducing human driving errors. But is this truly a straightforward assumption? In our contention, this assumption has potentially dangerous limits. This paper explores how well-understood and well-researched psychological and cognitive phenomena pertaining to human interaction with automation should not be properly labelled as misuse. Framing the problem through an automation bias lens, we argue that such so-called instances of misuse can instead be seen as predictable by-products of specific engineering design choices. We engage empirical data to problematize the assumption that automating driving functions directly leads to increased safety. Our conclusion calls for more transparent testing and safety data on the part of manufacturers, for updated notions of misuse in legal contexts, and for updated driver training regimes.
AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid) receptors (AMPARs) mediate fast excitatory neurotransmission in the brain. AMPARs form by homo- or heteromeric assembly of subunits encoded by the GRIA1-GRIA4 genes, of which only GRIA3 is X-chromosomal. Increasing numbers of GRIA3 missense variants are reported in patients with neurodevelopmental disorders (NDD), but only a few have been examined functionally. Here, we evaluated the impact on AMPAR function of one frameshift and 43 rare missense GRIA3 variants identified in patients with NDD by electrophysiological assays. Thirty-one variants alter receptor function and show loss-of-function (LoF) or gain-of-function (GoF) properties, whereas 13 appeared neutral. We collected detailed clinical data from 25 patients (from 23 families) harbouring 17 of these variants. All patients had global developmental impairment, mostly moderate (9/25) or severe (12/25). Twelve patients had seizures, including focal motor (6/12), unknown onset motor (4/12), focal impaired awareness (1/12), (atypical) absence (2/12), myoclonic (5/12), and generalized tonic-clonic (1/12) or atonic (1/12) seizures. The epilepsy syndrome was classified as developmental and epileptic encephalopathy in eight patients, developmental encephalopathy without seizures in 13 patients, and intellectual disability with epilepsy in four patients. Limb muscular hypotonia was reported in 13/25, and hypertonia in 10/25. Movement disorders were reported in 14/25, with hyperekplexia or non-epileptic erratic myoclonus being the most prevalent feature (8/25). Correlating receptor functional phenotype with clinical features revealed clinical features for GRIA3-associated NDDs and distinct NDD phenotypes for LoF and GoF variants. GoF variants were associated with more severe outcomes: patients were younger at the time of seizure onset (median age one month), hypertonic, and more often had movement disorders, including hyperekplexia. Patients with LoF variants were older at the time of seizure onset (median age 16 months), hypotonic, and had sleeping disturbances. LoF and GoF variants were disease-causing in both sexes but affected males often carried de novo or hemizygous LoF variants inherited from healthy mothers, whereas all but one affected females had de novo heterozygous GoF variants.
BACKGROUND Primary aldosteronism, characterized by overt renin-independent aldosterone production, is a common but underrecognized form of hypertension and cardiovascular disease. Growing evidence suggests that milder and subclinical forms of primary aldosteronism are highly prevalent, yet their contribution to cardiovascular disease is not well characterized. METHODS This prospective study included 1284 participants between the ages of 40 and 69 years from the randomly sampled population-based CARTaGENE cohort (Québec, Canada). Regression models were used to analyze associations of aldosterone, renin, and the aldosterone-to-renin ratio with the following measures of cardiovascular health: arterial stiffness, assessed by central blood pressure (BP) and pulse wave velocity; adverse cardiac remodeling, captured by cardiac magnetic resonance imaging, including indexed maximum left atrial volume, left ventricular mass index, left ventricular remodeling index, and left ventricular hypertrophy; and incident hypertension. RESULTS The mean (SD) age of participants was 54 (8) years and 51% were men. The mean (SD) systolic and diastolic BP were 123 (15) and 72 (10) mm Hg, respectively. At baseline, 736 participants (57%) had normal BP and 548 (43%) had hypertension. Higher aldosterone-to-renin ratio, indicative of renin-independent aldosteronism (ie, subclinical primary aldosteronism), was associated with increased arterial stiffness, including increased central BP and pulse wave velocity, along with adverse cardiac remodeling, including increased indexed maximum left atrial volume, left ventricular mass index, and left ventricular remodeling index (all P <0.05). Higher aldosterone-to-renin ratio was also associated with higher odds of left ventricular hypertrophy (odds ratio, 1.32 [95% CI, 1.002–1.73]) and higher odds of developing incident hypertension (odds ratio, 1.29 [95% CI, 1.03–1.62]). All the associations were consistent when assessing participants with normal BP in isolation and were independent of brachial BP. CONCLUSIONS Independent of brachial BP, a biochemical phenotype of subclinical primary aldosteronism is negatively associated with cardiovascular health, including greater arterial stiffness, adverse cardiac remodeling, and incident hypertension.
Due to the ongoing scarcity of copper resources globally, the extraction of copper from waste rocks has become an unavoidable necessity. This study investigated the phytoextraction of copper from low-grade chalcocite (LGC) ore using Tagetes sp. Therefore, the LGC and the garden soil mixtures, with different percentages, were utilized to achieve the optimum condition in 4 weeks. Mixing 50% LGC with 50% soil results in the best uptake value and translocation factor (TF) of 0.42 mg and 1.02, with shoot and root weights of 3.78 and 1.02 g, respectively. However, the highest BCFShoot (bio-concentration factor) and BCFRoot values are 0.65 and 1.66, with shoot and root weights of 2.65 g and 0.5 g, respectively, using 25% LGC + 75% soil. Therefore, at the proportion of 25% of the LGC, it can be concluded that the plant is a moderate accumulator and hyperaccumulator, respectively, for the shoot and root. Both proportions of 25% of the LGC and 50% of the LGC can be selected as optimum conditions for the mixture. If the target is the highest Cu accumulation in the above-ground tissues, the mixture containing 50% LGC should be selected. However, if harvesting the plant roots is possible, the mixture of 25% LGC + 75% soil has a better result because of the highest Cu concentration in the roots. Hence, Tagetes sp. exhibits the capability for extracting copper from low-grade chalcocite.
Objectives In response to COVID-19’s first wave, provincial governments rapidly implemented several public health directives, including isolation measures and care facility visitor restrictions, which profoundly affected healthcare delivery at the end of life and dying experiences and perceptions. The objective of this study was to identify implications of early policy changes for dying at home. Methods Analysis of interviews with 29 key informants with expertise in the policy and practice context of dying at home and care for those dying at home was conducted as part of a larger mixed-methods study on dying at home in Canada. Results Initial pandemic policy responses, especially visitor restrictions and limitations to home care services, shaped dying at home in relation to three themes: (1) increasing preferences and demand for, yet constrained system ability to support dying at home; (2) reinforcing and illuminating systemic reliance on and need for family/friend caregivers and community organizations, while constraining their abilities to help people die at home; and (3) illuminating challenges in developing and implementing policy changes during a pandemic, including equity-related implications. Conclusion This study contributes to broader understanding of the multifaceted impacts of COVID-19 policy responses in various areas within Canadian healthcare systems. Implications for healthcare delivery and policy development include (1) recognizing the role of family/friend caregivers and community organizations in end-of-life care, (2) recognizing health inequities at the end of life, and (3) considering possible changes in future end-of-life preferences and public attitudes about dying at home and responsibility for end-of-life care.
The prevalence of type 2 diabetes (T2D) is increasing among non-Hispanic Black and Hispanic communities, especially among men who develop this chronic condition at earlier ages. Personal agency and social support are vital aspects to diabetes management. However, less is known about the relationship between these variables among men living with diabetes. The purposes of this study were to identify (1) levels of personal agency to manage health, (2) sources of social supports to manage health based on personal agency levels, and (3) factors associated with lower personal agency to manage health. Cross-sectional data from non-Hispanic Black ( n = 381) and Hispanic ( n = 292) men aged 40 years or older with T2D were collected using an internet-delivered questionnaire. Three binary logistic regression models were fitted to assess sociodemographics, health indicators, and support sources associated with weaker personal agency to manage health. About 68% of participants reported having the strongest personal agency relative to 32.1% reporting weaker personal agency. Men who relied more on their spouse/partner (odds ratio [OR] = 1.22, p = .025), coworkers (OR = 1.59, p = .008), or faith-based organizations (OR = 1.29, p = .029) for ongoing help/support to improve their health and manage health problems were more likely to have weaker personal agency. Conversely, men who relied more on their health care providers for ongoing help/support to improve their health and manage health problems were less likely to have weaker personal agency to manage health (OR = 0.74, p < .001). Findings suggest personal agency may influence men’s support needs to manage T2D, which may also be influenced by cultural, socioeconomics, and the composition of social networks.
Background The HIV/AIDS pandemic remains a significant public health issue, with sub-Saharan Africa (SSA) at its epicentre. Although antiretroviral therapy (ART) has been introduced to decrease new infections and deaths, SSA reports the highest incidence of HIV/AIDS, constituting two-thirds of the global new infections. This review aimed to elucidate the predominant barriers and facilitators influencing ART adherence and to identify effective strategies to enhance ART adherence across SSA. Methods A comprehensive review was conducted on studies examining barriers to ART adherence and interventions to boost adherence among HIV-positive adults aged 15 and above in SSA, published from January 2010 onwards. The research utilized databases like Medline Ovid, CINAHL, Embase, and Scopus. Included were experimental and quasi-experimental studies, randomized and non-randomized controlled trials, comparative before and after studies, and observational studies such as cross-sectional, cohort, prospective and retrospective studies. Two independent reviewers screened the articles, extracted pertinent data, and evaluated the studies’ methodological integrity using Joanna Briggs Institute’s standardized appraisal tools. The compiled data underwent both meta-analysis and narrative synthesis. Results From an initial pool of 12,538 papers, 45 were selected (30 for narrative synthesis and 15 for meta-analysis). The identified barriers and facilitators to ART adherence were categorized into seven principal factors: patient-related, health system-related, medication-related, stigma, poor mental health, socioeconomic and socio-cultural-related factors. Noteworthy interventions enhancing ART adherence encompassed counselling, incentives, mobile phone short message service (SMS), peer delivered behavioural intervention, community ART delivery intervention, electronic adherence service monitoring device, lay health worker lead group intervention and food assistance. The meta-analysis revealed a statistically significant difference in ART adherence between the intervention and control groups (pooled OR = 1.56, 95%CI:1.35–1.80, p = <0.01), with evidence of low none statistically significant heterogeneity between studies ( I 2 = 0%, p = 0.49). Conclusion ART adherence in SSA is influenced by seven key factors. Multiple interventions, either standalone or combined, have shown effectiveness in enhancing ART adherence. To optimize ART’s impact and mitigate HIV’s prevalence in SSA, stakeholders must consider these barriers, facilitators, and interventions when formulating policies or treatment modalities. For sustained positive ART outcomes, future research should target specific underrepresented groups like HIV-infected children, adolescents, and pregnant women in SSA to further delve into the barriers, facilitators and interventions promoting ART adherence.
Introduction Given the high prevalence of mental health disorders and their significant socioeconomic burden, there is a need to develop improved treatments, and to evaluate them through placebo-controlled trials. However, the magnitude of the placebo response in randomised controlled trials to test medications may be substantial, affecting their interpretation. Therefore, improved understanding of the patient, trial and mental disorder factors that influence placebo responses would inform clinical trial design to better detect active treatment effects. There is a growing literature exploring the placebo response within specific mental health disorders, but no overarching synthesis of this research has been produced to date. We present a protocol for an umbrella review of systematic reviews and/or meta-analyses in which we aim to understand the effect size and potential predictors of placebo response within, and across, mental health disorders. Methods and analysis We will systematically search databases (Medline, PsycINFO, EMBASE+EMBASE Classic, Web of Knowledge) for systematic reviews and/or meta-analyses that report placebo effect size in clinical trials in patients with mental health disorders (initial search date 23 October 2022). Screening of abstracts and full texts will be done in pairs. We will extract data to qualitatively examine how placebo effect size varies across mental health disorders. We also plan to qualitatively summarise predictors of increased placebo response identified either quantitatively (eg, through meta-regression) or qualitatively. Risk of bias will be assessed using the AMSTAR-2 tool. We aim to not only summarise the current literature but also to identify gaps in knowledge and generate further hypotheses. Ethics and dissemination We do not believe there are any specific ethical considerations relevant to this study. We will publish the results in a peer-reviewed journal.
Lithium salts continue to find pharmaceutical applications, particularly as psychiatric medications. As with any active pharmaceutical ingredient, structural polymorphism is an important concern for lithium-based medications which can influence solubility and other physicochemical properties. Here we report a 13C, 1H, and 7Li magic-angle spinning solid-state nuclear magnetic resonance (MAS SSNMR) study of two 1:1 polymorphic ionic cocrystals of lithium 4-methoxybenzoate and L-proline (L4MPRO(α) and L4MPRO(β)). One-dimensional 13C cross-polarization magic-angle spinning and two-dimensional heteronuclear correlation NMR spectra hint at differential mobilities of the proline and benzoate moieties for the two polymorphs. Five key resonances differ in 13C chemical shift by more than 1 ppm between the two polymorphs, clearly distinguishing between them. Gauge-including projector-augmented-wave density functional theory (GIPAW DFT) calculations of 13C and 1H magnetic shielding constants correlate strongly with the experimental chemical shifts for both polymorphs. R2 and root-mean-square deviation metrics are shown to be insufficient in the case of 13C, but sufficient in the case of 1H, for differentiating between the polymorphs. 7Li satellite-transition MAS NMR of both polymorphs are identical, as are the computed lithium magnetic shielding constants, demonstrating the insensitivity of 7Li NMR to polymorphism in these samples. This work highlights the utility of solid-state NMR spectroscopy for examining ionic salt cocrystals and also highlights some caveats in this regard.
Objective To 1) describe primary care provider (PCP) practices for the assessment and management of females with urinary incontinence (UI), and 2) appraise these practices relative to recommendations made in high‐quality clinical guidelines. Methods Studies were searched in four databases (Medline, EMBASE, CINAHL, Web of Science) from their respective inception dates to March 6, 2023. All studies describing UI evaluation and management practices used by PCPs for female patients were eligible. Two reviewers independently selected studies, assessed their quality and extracted data. A narrative synthesis of included studies was performed to describe practices. Relevant evaluation and management practices were then compared to recommendations that were consistent across current high‐quality UI guidelines. Pharmacotherapy, referrals and follow‐ups were reported descriptively only. Results A total of 3475 articles were retrieved and, among those, 31 were included in the review. The majority reported a poor to moderate adherence to performing a pelvic exam (reported adherence range: 23‐76%; based on n=8 studies), abdominal examination (0‐87%; n=3), pelvic floor muscle assessment (9‐36%; n=2), and bladder diary (0‐92%; n=9), while there was high adherence to urinalysis (40‐97%; n=9). For the conservative management of UI, studies revealed a poor to moderate adherence to recommendations for pelvic floor muscle training (5‐82%; n=9), bladder training (2‐53%; n=8) and lifestyle interventions (1‐71%; n=6). Regarding pharmacotherapy, PCPs predominantly prescribed antimuscarinics (2‐46%; n=9) and estrogen (2‐77%; n=7). Lastly, PCPs referred those reporting UI to medical specialists (5‐37%; n=14). Referrals were generally made less than 30 days after diagnosis with urologists being the most sought out professional to assess and treat UI. Conclusion This review revealed poor to moderate adherence to clinical practice guideline recommendations. While these findings reflect high variability in reporting, the key message is that most aspects of patient care for female UI provided by PCPs needs to improve.
In 2018, Nigeria began the implementation of a cash transfer programme (CCT) for poor and vulnerable people. We evaluated the impact of cash transfer on household livelihood outcomes in Nigeria. Using multistage cluster sampling methodology, beneficiaries and non-beneficiaries within the same locality were randomly selected to participate in a survey to assess the impact of cash transfer on food security and food diversity. When gender, marital status, educational status, and age were controlled, beneficiaries were about three times more likely than non-beneficiaries to report experiencing little or no hunger. Children 0–59 months of beneficiaries were twice likely to have at least three meals a day compared to children of non-beneficiaries. Difference in differences regression analysis showed that on the average, beneficiaries of the cash transfer significantly consumed more diverse food than non-beneficiaries. Beneficiaries of the CCT experienced fewer episodes of severe hunger, have more meal frequency, and higher household dietary diversity than non-beneficiaries. This shows that the CCT programme is effective and can directly mitigate adverse effects of malnutrition with its long-term negative impact on children and thus must be expanded to more vulnerable people across all states in Nigeria.
Pain is one of the most prevalent and burdensome pediatric cancer symptoms for young children and their families. A significant proportion of pain episodes are experienced in environments where management options are limited, including at home. Digital innovations such as apps may have positive impacts on pain outcomes for young children in these environments. Our overall aim is to co-design such an app and the objective of this study was to explore the perceptions of children’s parents about app utility, needed system features, and challenges. We recruited parents of young children with cancer and multidisciplinary pediatric oncology clinicians from two pediatric cancer care centers to participate in audio-recorded, semi-structured, co-design interviews. We conducted interviews structured around technology acceptance and family caregiving theories until data saturation was reached. Audio-recordings were then transcribed, coded, and analyzed using thematic analysis. Forty-two participants took part in the process. Participants endorsed the concept of an app as a useful, safe, and convenient way to engage caregivers in managing their young child’s pain. Overall, the app was valued as a means to provide real-time, multimodal informational and procedural pain support to parents, while also reducing the emotional burden of pain care. Recommendations for intervention design included accessibility-focused features, comprehensive symptom tracking, and embedded scientific- and clinically-sound symptom assessments and management advice. Predicted challenges to app use included the workload burden it may place on parents and clinicians. The insights gathered will inform the design principles of our future childhood cancer pain digital research.
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21,291 members
Raluca Balan
  • Department of Mathematics and Statistics
Dan Ionescu
  • School of Electrical Engineering and Computer Science
Nianqiang Li
  • School of Electrical Engineering and Computer Science
Kallol Dutta
  • Department of Cellular and Molecular Medicine
Sanni Yaya
  • School of International Development and Global Studies
120 University, K1N 6N5, Ottawa, ON, Canada
Head of institution
Jacques Fremont