693 results match your criteria: "Schulich School of Engineering[Affiliation]"

Nanoparticle-based nanocomposite coatings with postprocessing for enhanced antimicrobial capacity of polymeric film.

Biotechnol Bioeng

February 2024

Department of Biomedical Engineering, Schulich School of Engineering, University of Calgary, Calgary, Alberta, Canada.

Bacterial adhesion and biofilm formation on surfaces pose a significant risk of microbial contamination and chronic diseases, leading to potential health complications. To mitigate this concern, the implementation of antibacterial coatings becomes paramount in reducing pathogen propagation on contaminated surfaces. To address this requirement, our study focuses on developing cost-effective and sustainable methods using polymer composite coatings.

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Mechanism and Development of Thermo-Rheological Properties of Asphalts Modified by Reactive Polymer Systems.

Materials (Basel)

October 2023

Bituminous Materials Chair, Department of Civil Engineering, Schulich School of Engineering, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada.

The new class of reactive polymers is designed to modify asphalt through chemical reactions with asphalt components. The complexity of such systems and the long experience with thermoplastic elastomers as well as with some other "classical" modifiers, and to a degree that our present testing methods and even specifications revolve around these materials, might obscure the fact that we are dealing with rather different modification systems and possibly with new emerging asphalt paving technologies. Our present work attempted to compare two different reactive polymer systems with the "classical" system which uses thermoplastic elastomer.

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A series of petroleum coke (petcoke)-derived solid acid catalysts were prepared via nitric acid treatment with or without ball milling pretreatment. The inherent sulfur in petcoke was converted to sulfonic groups, which were active sites for the esterification of octanoic acid and methanol at 60 °C, with ester yields of 14-43%. More specifically, samples without ball milling treated at 120 °C for 3 h had a total acidity of 4.

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Upscaling of dispersion in gas-liquid absorption on an inclined surface.

Phys Rev E

September 2023

Department of Chemical and Petroleum Engineering, Schulich School of Engineering, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada.

We extend the Taylor-Aris dispersion theory to upscale the gas absorption into a viscous incompressible liquid flowing along an inclined surface. A reduced-order model of advection-dispersion-reaction is developed with the aid of Reynolds decomposition and cross-sectional averaging techniques. The upscaled model allowed evaluation of the dispersion, advection, and absorption kinetics as a function of the Peclet number (Pe) and the Damköhler number (Da).

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Bioprocess development for cord blood mesenchymal stromal cells on microcarriers in Vertical-Wheel bioreactors.

Biotechnol Bioeng

January 2024

Pharmaceutical Production Research Facility, Schulich School of Engineering, University of Calgary, Calgary, Alberta, Canada.

Equine mesenchymal stromal cells (MSCs) have been found to be beneficial for the treatment of many ailments, including orthopedic injuries, due to their superior differentiation potential and immunomodulating properties. Cell therapies require large cell numbers, which are not efficiently generated using conventional static expansion methods. Expansion of equine cord blood-derived MSCs (eCB-MSCs) in bioreactors, using microcarriers as an attachment surface, has the potential to generate large numbers of cells with increased reproducibility and homogeneity compared with static T-flask expansion.

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Vessel Metrics: A software tool for automated analysis of vascular structure in confocal imaging.

Microvasc Res

January 2024

Alberta Children's Hospital Research Institute, University of Calgary, T2N 4N1, Canada; Libin Institute, University of Calgary, T2N 4N1, Canada; Department of Biochemistry and Molecular Biology, University of Calgary, T2N 4N1, Canada. Electronic address:

Images contain a wealth of information that is often under analyzed in biological studies. Developmental models of vascular disease are a powerful way to quantify developmentally regulated vessel phenotypes to identify the roots of the disease process. We present vessel Metrics, a software tool specifically designed to analyze developmental vascular microscopy images that will expedite the analysis of vascular images and provide consistency between research groups.

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Estimation of natural methane emissions from the largest oil sand deposits on earth.

PNAS Nexus

September 2023

Department of Chemical and Petroleum Engineering, Schulich School of Engineering, University of Calgary, Calgary, AB T2N 1N4, Canada.

Worldwide methane emission by various industrial sources is one of the important human concerns due to its serious climate and air-quality implications. This study investigates less-considered diffusive natural methane emissions from the world's largest oil sand deposits. An analytical model, considering the first-order methane degradation, in combination with Monte Carlo simulations, is used to quantitatively characterize diffusive methane emissions from Alberta's oil sands formations.

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AI-powered assessment of biomarkers for growth prediction of abdominal aortic aneurysms.

JVS Vasc Sci

July 2023

Department of Biomedical Engineering, Schulich School of Engineering, University of Calgary, Calgary, AB, Canada.

Objective: The purpose of this study was to employ biomechanics-based biomarkers to locally characterize abdominal aortic aneurysm (AAA) tissue and investigate their relation to local aortic growth by means of an artificial intelligence model.

Methods: The study focused on a population of 36 patients with AAAs undergoing serial monitoring with electrocardiogram-gated multiphase computed tomography angiography acquisitions. The geometries of the aortic lumen and wall were reconstructed from the baseline scans and used for the baseline assessment of regional aortic weakness with three functional biomarkers, time-averaged wall-shear stress, in vivo principal strain, and intra-luminal thrombus thickness.

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Background And Goal: characterization of brain lesion types in multiple sclerosis (MS) has been an ongoing challenge. Based on verified texture analysis measures from clinical magnetic resonance imaging (MRI), this study aimed to develop a method to identify two extremes of brain MS lesions that were approximately severely demyelinated (sDEM) and highly remyelinated (hREM), and compare them in terms of common clinical variables.

Method: Texture analysis used an optimized gray-level co-occurrence matrix (GLCM) method based on FLAIR MRI from 200 relapsing-remitting MS participants.

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Critical considerations in determining the surface charge of small extracellular vesicles.

J Extracell Vesicles

September 2023

Pharmaceutical Production Research Facility, Department of Chemical and Petroleum Engineering, Schulich School of Engineering, University of Calgary, Calgary, Alberta, Canada.

Small extracellular vesicles (EVs) have emerged as a focal point of EV research due to their significant role in a wide range of physiological and pathological processes within living systems. However, uncertainties about the nature of these vesicles have added considerable complexity to the already difficult task of developing EV-based diagnostics and therapeutics. Whereas small EVs have been shown to be negatively charged, their surface charge has not yet been properly quantified.

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Physiological oxygen conditions enhance the angiogenic properties of extracellular vesicles from human mesenchymal stem cells.

Stem Cell Res Ther

August 2023

Pharmaceutical Production Research Facility, Schulich School of Engineering, University of Calgary, 2500 University Drive N.W., Calgary, AB, T2N 1N4, Canada.

Background: Following an ischemic injury to the brain, the induction of angiogenesis is critical to neurological recovery. The angiogenic benefits of mesenchymal stem cells (MSCs) have been attributed at least in part to the actions of extracellular vesicles (EVs) that they secrete. EVs are membrane-bound vesicles that contain various angiogenic biomolecules capable of eliciting therapeutic responses and are of relevance in cerebral applications due to their ability to cross the blood-brain barrier (BBB).

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Biaxial driving can more efficiently convert electrical power to forward acoustic power in piezoelectric materials, and the interaction between the orthogonal electric fields can produce a combination of extensional and shear deformations as a function of the phase difference between them to allow dynamic steering of the beam with a single-element. In this study, we demonstrate for the first time the application of a single-element biaxially driven ring transducerfor blood-brain barrier opening in mice, and compare it to that achieved with a conventional single-element highly focused (F# = 0.7) spherical transducer operating at a similar frequency.

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Computed tomography (CT) offers advanced biomedical imaging of the body and is broadly utilized for clinical diagnosis. Traditionally, clinical CT scans have not been used for volumetric bone mineral density (vBMD) assessment; however, computational advances can now leverage clinically obtained CT data for the secondary analysis of bone, known as opportunistic CT analysis. Initial applications focused on using clinically acquired CT scans for secondary osteoporosis screening, but opportunistic CT analysis can also be applied to answer research questions related to vBMD changes in response to various disease states.

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Bioretention cells, or rain gardens, can effectively reduce many contaminants in polluted stormwater through phytoremediation and bioremediation. The vegetated soil structure develops bacterial communities both within the soil and around the vegetation roots that play a significant role in the bioremediative process. Prediction of a bioretention cell's performance and efficacy is essential to the design process, operation, and maintenance throughout the design life of the cell.

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Placing a stronger focus on subject-specific responses to footwear may lead to a better functional understanding of footwear's effect on running and its influence on comfort perception, performance, and pathogenesis of injuries. We investigated subject-specific responses to different footwear conditions within ground reaction force (GRF) data during running using a machine learning-based approach. We conducted our investigation in three steps, guided by the following hypotheses: (I) For each subject x footwear combination, unique GRF patterns can be identified.

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Designing efficient and labor-saving prosthetic hands requires powerful hand gesture recognition algorithms that can achieve high accuracy with limited complexity and latency. In this context, the paper proposes a Compact Transformer-based Hand Gesture Recognition framework referred to as [Formula: see text], which employs a vision transformer network to conduct hand gesture recognition using high-density surface EMG (HD-sEMG) signals. Taking advantage of the attention mechanism, which is incorporated into the transformer architectures, our proposed [Formula: see text] framework overcomes major constraints associated with most of the existing deep learning models such as model complexity; requiring feature engineering; inability to consider both temporal and spatial information of HD-sEMG signals, and requiring a large number of training samples.

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Mechanistic Insight into Electrode Processes by Operando Visualization of Interfacial pH Using Fluorescent Nanosensors.

Environ Sci Technol

July 2023

Department of Chemical and Petroleum Engineering, Schulich School of Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada.

Operando visualization of interfacial pH is crucial, yet challenging in electrochemical processes. Herein, we report the fabrication and utilization of ratiometric, fluorescent pH-sensitive nanosensors for operando quantification of fast-dynamic, interfacial pH changes in electrochemical processes and environments where unprotected fluorescent dyes would be degraded. Spatio-temporal pH changes were detected using an electrochemically coupled laser scanning confocal microscope (EC-LSCM) during the electrocoagulation treatment of model and field samples of oil-sands-produced water.

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Anode fouling is one of the key limiting factors to the widespread application of electrocoagulation (EC) for treatment of different types of contaminated water. Promising mitigation strategy to fouling is to operate the process under polarity reversal (PR) instead of direct current (DC). However, the PR operation comes at the cost of process complexity due to the alternation of electrochemical and chemical reactions.

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Promoting bone healing including fracture non-unions are promising targets for bone tissue engineering due to the limited success of current clinical treatment methods. There has been significant research on the use of stem cells with and without biomaterial scaffolds to treat bone fractures due to their promising regenerative capabilities. However, the relative roles of exogenous vs.

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In this cross-sectional study, we compared patellofemoral geometry in individuals with a youth-sport-related intra-articular knee injury to uninjured individuals, and the association between patellofemoral geometry and magnetic resonance imaging (MRI)-defined osteoarthritis (OA) features. In the Youth Prevention of Early OA (PrE-OA) cohort, we assessed 10 patellofemoral geometry measures in individuals 3-10 years following injury compared with uninjured individuals of similar age, sex, and sport, using mixed effects linear regression. We also dichotomized geometry to identify extreme (>1.

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Unlabelled: Rapid bone loss can occur after spinal cord injury (SCI) and a standard of care to prevent or treat this phenomenon is an active area of research. Using advanced analysis techniques, this study demonstrates that zoledronic acid, a possible treatment, prevented loss of bone strength at the hip following SCI.

Introduction: Bone loss below the level of neurological lesion is a well-known complication of spinal cord injury (SCI), and effective preventive treatment for this phenomenon is an active area of research.

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Background: Induced pluripotent stem cells (iPSCs) offer potential to revolutionize regenerative medicine as a renewable source for islets, dopaminergic neurons, retinal cells, and cardiomyocytes. However, translation of these regenerative cell therapies requires cost-efficient mass manufacturing of high-quality human iPSCs. This study presents an improved three-dimensional Vertical-Wheel® bioreactor (3D suspension) cell expansion protocol with comparison to a two-dimensional (2D planar) protocol.

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. Focused ultrasound (FUS) neuromodulation non-invasively alters brain activity, likely via acoustic radiation force with dynamics of the pulse repetition frequency (PRF). PRF impacts neuromodulation as well as indirect auditory activation, a confound linked to skull vibrations.

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Bacterial nanocellulose (BNC) is a naturally derived hydrogel that has recently paved its way in several biomedical applications. Despite its remarkable tissue-like properties, BNC does not express innate anticoagulant or antimicrobial properties; therefore, appropriate post-modification procedures are required to prevent nonspecific adhesion and enhance the hemocompatibility properties of BNC-based biointerface. Here, we report a new class of flexible, lubricant-infused BNC membranes with superior antithrombotic and antibacterial properties.

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BOLD sensitivity to baseline perfusion and blood volume is a well-acknowledged fMRI confound. Vascular correction techniques based on cerebrovascular reactivity (CVR) might reduce variance due to baseline cerebral blood volume, however this is predicated on an invariant linear relationship between CVR and BOLD signal magnitude. Cognitive paradigms have relatively low signal, high variance and involve spatially heterogenous cortical regions; it is therefore unclear whether the BOLD response magnitude to complex paradigms can be predicted by CVR.

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