SCRIPTORIUM (Université de Moncton)
Not a member yet
2550 research outputs found
Sort by
Plant Fibers as Composite Reinforcements For Biomedical Applications
No full textPlant fibers possess high strength, high fracture toughness and elasticity, and have proven useful because of their diversity, versatility, renewability, and sustainability. For biomedical applications, these natural fibers have been used as reinforcement for biocomposites to infer these hybrid biomaterials mechanical characteristics, such as stiffness, strength, and durability. The reinforced hybrid composites have been tested in structural and semi-structural biodevices for potential applications in orthopedics, prosthesis, tissue engineering, and wound dressings. This review introduces plant fibers, their properties and factors impacting them, in addition to their applications. Then, it discusses different methodologies used to prepare hybrid composites based on these widespread, renewable fibers and the unique properties that the obtained biomaterials possess. It also examines several examples of hybrid composites and their biomedical applications. Finally, the findings are summed up and some thoughts for future developments are provided. Overall, the focus of the present review lies in analyzing the design, requirements, and performance, and future developments of hybrid composites based on plant fibers.udemauteur: Si Amar Dahouman
Molecular Understanding of ACE-2 and HLA-Conferred Differential Susceptibility to COVID-19: Host-Directed Insights Opening New Windows in COVID-19 Therapeutics
No full textThe genetic variants of HLAs (human leukocyte antigens) play a crucial role in the virus–host interaction and pathology of COVID-19. The genetic variants of HLAs not only influence T cell immune responses but also B cell immune responses by presenting a variety of peptide fragments of invading pathogens. Peptide cocktail vaccines produced by using various conserved HLA-A2 epitopes provoke substantial specific CD8+ T cell responses in experimental animals. The HLA profiles vary among individuals and trigger different T cell-mediated immune responses in COVID-19 infections. Those with HLA-C*01 and HLA-B*44 are highly susceptible to the disease. However, HLA-A*02:01, HLA-DR*03:01, and HLA-Cw*15:02 alleles show resistance to SARS infection. Understanding the genetic association of HLA with COVID-19 susceptibility and severity is important because it can help in studying the transmission of COVID-19 and its physiopathogenesis. The HLA-C*01 and B*44 allele pathways can be studied to gain insight into disease transmission and physiopathogenesis. Therefore, integrating HLA testing is suggested in the ongoing pandemic, which will help in the rapid identification of highly susceptible populations worldwide and possibly acclimate vaccine development. Therefore, understanding the correlation between HLA and SARS-CoV-2 is critical in opening new insights into COVID-19 therapeutics, based on previous studies conducted.udemauteur: Mehtab Kha
Reinforcement learning for swarm robotics: An overview of applications, algorithms and simulators
No full textRobots such as drones, ground rovers, underwater vehicles and industrial robots have increased in popularity in recent years. Many sectors have benefited from this by increasing productivity while also decreasing costs and certain risks to humans. These robots can be controlled individually but are more efficient in a large group, also known as a swarm. However, an increase in the quantity and complexity of robots creates the need for an adequate control system. Reinforcement learning, an artificial intelligence paradigm, is an increasingly popular approach to control a swarm of unmanned vehicles. The quantity of reviews in the field of reinforcement learning-based swarm robotics is limited. We propose reviewing the various applications, algorithms and simulators on the subject to fill this gap. First, we present the current applications on swarm robotics with a focus on reinforcement learning control systems. Subsequently, we define important reinforcement learning terminologies, followed by a review of the current state-of-the-art in the field of swarm robotics utilizing reinforcement learning. Additionally, we review the various simulators used to train, validate and simulate swarms of unmanned vehicles. We finalize our review by discussing our findings and the possible directions for future research. Overall, our review demonstrates the potential and state-of-the-art reinforcement learning-based control systems for swarm robotics.udemauteur: Moulay Akhlouf
External Post Tensioning Evaluation Using Vibration Response Measurements
No full textExternal post-tensioning tendons (EPTTs) are commonly used in concrete box girder bridges constructed using the balanced cantilever methods. Bridge managers and operators are increasingly interested in novel means of determining the health of these important structural components as traditional visual inspections provide little to no information on their state. Due to inferior grouting, corrosion of prestressing strands within some existing bridges have required replacement of EPTTs. Monitoring the structural vibration responses of EPTTs can provide a means to determine the remaining tension which provides crucial information on their state. The basic equations to determine the stress from the vibration responses are based on vibrating string theory. Many of the important parameters in the classical equations are difficult to precisely determine in the field (stiffness, length, support conditions, etc.) due to construction variability. The basic equations have been the foundation for the development of more complex equations that attempt to account for these variabilities. These theoretical equations have rarely been tested under uncontrolled conditions, such as for the evaluation of existing in-operation EPTTs. This paper will present the practical application of three theoretical equations presented in literature that have been developed for determining the tension in EPTTs. The equations make use of modal frequencies from eight different EPTTs of varying lengths in an existing concrete box girder bridge (the Confederation Bridge in eastern Canada). The aim of this study is to develop a testing methodology based on vibration monitoring that provides reliable results and that is more efficient than the static deflection technique currently used by bridge managers/operators. Results show that the monitoring of structural vibration responses is an efficient and reliable way of determining the tension in external post-tensioning tendons.udemauteur: Serge Desjardin
Exploring High School Students Career Inetrest in Aging for a Sustainable Workforce
No full textA scarcity of workers calls into doubt our capacity to support and care for an aging population. To gain a better understanding of the next generation of potential workers that will serve the aging population, 644 French-speaking students in grades 10 and 11 in the province of New Brunswick (Canada) were surveyed. The goals were to learn more about the attitudes, knowledge, and career interests that French-speaking, bilingual youth hold with respect to older adults. The participants’ responses indicate slightly positive attitudes toward older adults and little knowledge of this group. Results also showed that interest in a career working with older adults is primarily linked to holding positive attitudes toward them. By offering a deeper insight into young people’s perceptions of an aging population and contributing to a field lacking in research, the results of this study provide insight into measures that can be taken to ensure the future sustainability of the workforce for an aging population.udemauteur: Suzanne Dupuis-Blanchar
Recent Advances in Infrared Face Analysis and Recongition with Deep Learning
No full textBesides the many advances made in the facial detection and recognition fields, face recognition applied to visual images (VIS-FR) has received increasing interest in recent years, especially in the field of communication, identity authentication, public safety and to address the risk of terrorism and crime. These systems however encounter important problems in the presence of variations in pose, expression, age, occlusion, disguise, and lighting as these factors significantly reduce the recognition accuracy. To prevent problems in the visible spectrum, several researchers have recommended the use of infrared images. This paper provides an updated overview of deep infrared (IR) approaches in face recognition (FR) and analysis. First, we present the most widely used databases, both public and private, and the various metrics and loss functions that have been proposed and used in deep infrared techniques. We then review deep face analysis and recognition/identification methods proposed in recent years. In this review, we show that infrared techniques have given interesting results for face recognition, solving some of the problems encountered with visible spectrum techniques. We finally identify some weaknesses of current infrared FR approaches as well as many future research directions to address the IR FR limitations.udemauteur: Moulay Akhlouf
Challenges, Lessons Learned, and Implications for Conducting Nutrition/Health Research in Canadian Federal Correctional Facilities
No full textWhile conducting nutrition/health research into weight changes during incarceration and related determinants, it became apparent that the correctional setting in Canada was unique and required study design modifications to ensure study success. Consequently, we made many methodological adjustments during recruitment and data collection because of unforeseen challenges in the correctional context. This paper provides an illustrative example and shares insights on the challenges faced when conducting nutrition/health research in Canadian correctional facilities. Guidance on how to adapt research methods to make them more conducive to this unique environment is provided. This paper also highlights the importance of conducting nutrition/health research in this setting, especially given the lack of this type of research and the need for more evidence-based data to guide health promotion and nutritional interventions in Canadian correctional facilities.udemauteur: Claire Johnso
L'huile de poisson et une huile alimentaire riche en acide stéaridonique diminuent l'inflammation articulaire dans un modèle murin d'arthrite inflammatoire
No full textLes acides gras n-3 alimentaires marins ont des effets positifs pour la santé, mais dérivent de sources non renouvelables. Une alternative durable et efficace est l’huile végétale des graines de Buglossoides arvensis riche en acide stéaridonique (SDA). D’autre part, la polyarthrite rhumatoïde (PR) est affectée positivement par la consommation d’huiles marines qui sont impliquées dans la résolution de l’inflammation. L’huile de B. arvensis ne fut cependant pas encore évaluée sur la PR. L’hypothèse de cette étude est donc que la consommation d’huile de B. arvensis réduira la sévérité de l’inflammation liée à l’arthrite inflammatoire. Les objectifs sont de mesurer l’impact des diètes enrichies avec l’huile de B. arvensis ou de poisson, sur les différents stades de la maladie dans un modèle murin d’arthrite. Ceci implique aussi l’investigation des mécanismes moléculaires impliqués et de mesurer, en utilisant des smart cages, les changements dans le comportement et la locomotion des souris arthritiques. Pour ce faire, les souris C57BL/6 ont consommé une diète de base formulée selon le « régime occidental humain » typique ou la diète de base enrichie avec 3,3% (% d’energie) ou 10% d’huile de B. arvensis, ou 3,3% d’huile de poisson pendant 3 semaines. L’arthrite inflammatoire fut alors induite par injections de sérum de souris K/BxN aux jours 0 et 2. L’inflammation fut mesurée pour 14 jours par des mesures de scores cliniques et d’épaisseur des chevilles. Les cytokines des articulations furent mesurées par cyrtométrie en flux aux jours 4, 8 et 14. L’activité des souris fut aussi mesurée avec des smart cages durant 23h aux jours 0, 8 et 14 et à ces trois temps, les souris furent sacrifiées pour mesurer le profil d’acides gras dans les foies. Le poids des souris fut monitoré tout au long de l’expérience. En général, aucun changement dans le poids des souris ne fut observé. Les acides gras oméga-3 étaient augmentés dans les foies des souris consommant les diètes supplémentées avec l’huile de B. arvenis et l’huile de poisson (p<0,05, 1-way ANOVA). Le score clinique était moins élevé au jour 13 de l’arthrite pour toutes les diètes comparées à la diète contrôle et l’épaisseur des chevilles était moins élevée dans les groupes consommant les diètes à faible dose de B. arvenis et de poisson (p<0,05, 2-way ANOVA). La distance parcourue dans les smart cages était plus grande dans ces deux groupes et les cytokines pro-inflammatoires étaient moins abondantes. La quantification de médiateurs lipidiques est aussi prévue. Globalement, ces résultats ont démontré que les diètes à faible dose de B. arvensis et en huile de poisson avaient tendance à diminuer la sévérité de l’inflammation comparée aux autres diètes. Cette étude pourrait constituer la base d’un essai clinique pour évaluer l’huile de B. arvensis chez les patients atteints de PR
Les francophonies et la variation éd. par Hélène Boudreau, et Gudrun Ledegen
No full textudemauteur: Laurence Arrigh
Time-dependent metabolome and fatty acid profile changes following a high-fat diet exposure in Drosophila melanogaster
No full textHigh-fat diets (HFDs) are often used to study metabolic disorders using different animal models. However, the underlying cellular mechanisms pertaining to the concurrent loss of metabolic homeostasis characteristics of these disorders are still unclear mainly because the effects of such diets are also dependent on the time frame of the experiments. Here, we used the fruit fly, Drosophila melanogaster, to investigate the metabolic dynamic effects following 0, 2, 4, 7 and 9 days of an exposure to a HFD (standard diet supplemented with 20% w/v coconut oil, rich in 12:0 and 14:0) by combining NMR metabolomics and GC-FID fatty acid profiling. Our results show that after 2 days, the ingested 12:0 and 14:0 fatty acids are used for both lipogenesis and fatty acid oxidation. After 4 days, metabolites from several different pathways are highly modulated in response to the HFD, and an accumulation of 12:0 is also observed, suggesting that the balance of lipid, amino acid and carbohydrate metabolism is profoundly perturbed at this specific time point. Following a longer exposure to the HFD (and notably after 9 days), an accumulation of many metabolites is observed indicating a clear dysfunction of the metabolic system. Overall, our study highlights the relevance of the Drosophila model to study metabolic disorders and the importance of the duration of the exposure to a HFD to study the dynamics of the fundamental mechanisms that control metabolism following exposure to dietary fats. This knowledge is crucial to understand the development and progression of metabolic diseases.udemauteur: Jérémie Doiron; Mohamed Touaibia; Marc Surette; Nicolas Pichau