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Remote sensing and the UN Ocean Decade : high expectations, big opportunities
Get PDFThis year officially marks the beginning of the United Nations Decade of Ocean Science for Sustainable Development (2021–2030)—the Ocean Decade. A primary objective of this coordination framework is to support scientific research and technological developments that can contribute to the conservation and sustainable management of the world’s oceans. One of the seven Decade Outcomes is to secure healthy and resilient oceans where marine biodiversity is mapped and protected; however, fulfilling this goal will require data, knowledge, and technology. The use of remote sensing is now established in marine research and management and is crucial in developing our understanding of ocean patterns and processes at multiple spatial and temporal scales (e.g., Jawak et al., 2015). As such, remote sensing technology is expected to play a critical role in achieving the vision set by the Ocean Decade
Une approche thérapeutique basée sur les cellules souches musculaires en dystrophie myotonique de type 1
Get PDFLa dystrophie myotonique de type 1 (DM1) est une maladie héréditaire dominante où le muscle squelettique est sévèrement affecté. Les personnes atteintes présentent une faiblesse musculaire, une perte progressive de la force musculaire et de l’atrophie. La fonction des cellules souches musculaires (CSM) est également altérée en DM1 en présentant notamment un profil de sénescence prématurée, une capacité de prolifération et de fusion diminuée, mais aussi une différenciation en myotubes retardée. Le profil inflammatoire élevé mesuré chez les individus atteints de DM1 pourrait être, du moins en partie, responsable de l’altération de leur fonction. Actuellement, cette maladie reste incurable, mais il y a un haut potentiel thérapeutique dans le développement de stratégies permettant de restaurer la fonction des CSM. De plus, cette avenue demeure inexplorée. Afin de permettre l’avancement des connaissances dans ce domaine de recherche, ce mémoire présente un travail de recherche visant à développer une nouvelle avenue thérapeutique ciblant la fonction altérée des CSM ainsi que l’inflammation potentiellement présente au niveau musculaire en DM1. Pour répondre à ces objectifs, la force musculaire de 4 groupes musculaires a été mesurée chez 103 participants atteints de DM1, exprimée en valeur prédite, puis comparée entre les individus présentant des niveaux sériques normaux ou anormaux de cytokines pro inflammatoires. De plus, à partir de biopsies musculaires prélevées chez 10 patients DM1 et 15 sujets sains, la densité de cellules inflammatoires (macrophages) a été quantifiée dans les tissus musculaires DM1 et comparée aux tissus contrôles. Des CSM ont aussi été isolées à partir de ces biopsies et utilisées afin d’évaluer le niveau d’expression de certains gènes inflammatoires par technique de séquençage de cellules uniques et d’évaluer l’effet de certains médiateurs lipidiques sur la fonction CSM et ainsi que sur l’expression de certains gènes de l’inflammation. Les résultats de cette étude ont été présentés dans la production d’un article original portant sur l’étude des médiateurs lipidiques sur la fonction des CSM en DM1. En plus de confirmer l’inflammation systémique (sang) documentée chez les individus atteints de DM1, les résultats obtenus démontrent une inflammation locale (tissu musculaire et CSM) chez ceux-ci. Aussi, l’ajout exogène de certaines molécules appartenant à cette famille de médiateurs, dont certaines résolvines et marésines, améliore la prolifération, la différenciation et la fusion des CSM, et diminue significativement l’expression de certains gènes de l’inflammation. Ainsi, cette classe de médiateurs représente un nouvel espoir thérapeutique dans le développement de thérapies ciblant les fonctions altérées des CSM, mais également dans la résolution de l’inflammation en DM1 et autres maladies inflammatoires.
Myotonic dystrophy type 1 (DM1) is a dominant disease characterized by severely affected skeletal muscles. Individuals with DM1 experienced muscle weakness, progressive loss of muscle strength and atrophy. The function of muscle stem cells (MSC) is also altered in DM1 and they exhibit a premature senescence profile, decreased proliferation and fusion capacity and delayed differentiation into myotubes. At least, the highly inflammatory profile could be responsible of the impairment of their functions. Currently, there is no cure for this disease, but there is a high therapeutic potential in the development of strategies to restore MSC function. Moreover, this avenue remains unexplored. To increase knowledge in this field of research, this thesis presents an original manuscript on the study of lipid mediators on MSC function in DM1. In addition to confirm the systemic inflammation (blood) documented in DM1 patients, the results obtained demonstrate a local inflammation (in muscle tissue and MSC) in DM1 patients. Also, the exogenous addition of lipid mediators including resolvin and maresins family improves the proliferation, differentiation and fusion of MSC and significantly decreases the expression of inflammation genes. Thus, this class of mediators represents a new therapeutic hope to rescue MSC function and decrease inflammatory profile associated with DM1
Development of a dual capsule self-healing silicone composite using silicone chemistry and poly(melamine-urea-formaldehyde) shells
No full textThis study aims to develop microcapsules that can be used as room-temperature self-healing agents in silicone-based matrices. A telechelic reactive silanol-terminated polydimethylsiloxane (PDMS) as the healing agent, was selected to ensure the homogeneity of the polymeric matrix and encapsulated in poly(melamine-urea-formaldehyde) shells through an in-situ emulsion polymerization technique. To catalyze the polycondensation reaction of the healing agent, dibutyltin dilaurate (DBTL) was encapsulated within the same type of polymeric shell. The synthesized microcapsules were characterized using Fourier-transform infrared spectrometry, optical microscopy, scanning electron microscopy (SEM), and differential scanning calorimetry. The analyses confirmed that the spherical microcapsules with an average size of 56 μm for PDMS-MUF microcapsules and 42 μm for DBTL-MUF microcapsules, with a shell wall thickness of 100–200 nm, and good thermal stability were formed. Therefore, the two-component self-healing silicone composite was successfully developed using 10:1.2 wt% PDMS: DBTL microcapsules within the silicone matrix. SEM showed the self-healing ability of the silicone matrix by observing the successful healing of microcracks at room temperature. Tensile and trouser tear tests were adopted to assess the self-healing performance of the elastomeric matrix, showing the self-healing efficiencies of 67% and 55%, respectively
What is the prevalence of fear of cancer recurrence in cancer survivors and patients? A systematic review and individual participant data meta‐analysis
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Care for fear of cancer recurrence (FCR) is considered the most common unmet need among cancer survivors. Yet the prevalence of FCR and predisposing factors remain inconclusive. To support targeted care, we provide a comprehensive overview of the prevalence and severity of FCR among cancer survivors and patients, as measured using the short form of the validated Fear of Cancer Recurrence Inventory (FCRI-SF). We also report on associations between FCR and clinical and demographic characteristics.
Methods
This is a systematic review and individual participant data (IPD) meta-analysis on the prevalence of FCR. In the review, we included all studies that used the FCRI-SF with adult (≥18 years) cancer survivors and patients. Date of search: 7 February 2020. Risk of bias was assessed using the Joanna Briggs Institute critical appraisal tool.
Results
IPD were requested from 87 unique studies and provided for 46 studies comprising 11,226 participants from 13 countries. 9311 respondents were included for the main analyses. On the FCRI-SF (range 0–36), 58.8% of respondents scored ≥13, 45.1% scored ≥16 and 19.2% scored ≥22. FCR decreased with age and women reported more FCR than men. FCR was found across cancer types and continents and for all time periods since cancer diagnosis.
Conclusions
FCR affects a considerable number of cancer survivors and patients. It is therefore important that healthcare providers discuss this issue with their patients and provide treatment when needed. Further research is needed to investigate how best to prevent and treat FCR and to identify other factors associated with FCR.
The protocol was prospectively registered (PROSPERO CRD42020142185)
Moving toward sustainability and circularity in hill road construction: A study of barriers, practices, and performance
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This study explores the relationships among sustainability implementation barriers (resource,
managerial and regulatory barriers), sustainability practices (sustainable construction materials, sustainable
construction design, modern construction methods and environmental provisions and reporting) and
sustainability performance (environmental, economic and social) in hill road construction (HRC).
Design/methodology/approach
Primary data were collected from the 313 HRC practitioners with the help
of a questionnaire, and research hypotheses were tested employing structural equation modeling.
Findings
The findings reveal a mixed effect of sustainability implementation barriers. Resource
(managerial) barriers are negatively related to all practices except environmental provisions and reporting
(sustainable construction materials), while regulatory barriers only negatively impact modern construction
methods. On the other hand, all sustainability practices positively impact environmental performance, whereas
economic (social) performance is positively influenced by all practices, except environmental provisions and
reporting (modern construction methods), and positively affects economic performance.
Originality/value
In order to transform HRC toward sustainability, the barriers to sustainability
implementation, sustainability practices and performance need to be understood by practitioners; however, the
relationships have not previously been empirically assessed in extant literature. Besides, past research appears
to be predominantly focused on the environmental aspect, thereby neglecting economic and social aspects. This
study is a modest attempt to bridge these research gap
Listening with the invasive fish ear : applications and innovations of otolith chemistry analysis in invasive fish biology
Get PDFAcquisition of biological information on invasive fishes during the early stages of invasion could be critical in orienting subsequent management strategies. To achieve such a task, biological invasion researchers and practitioners take advantage of numerous technologies (e.g. genomics and acoustic telemetry). Surprisingly, the study of invasive fish ecology by analysis of the chemical composition of calcium carbonate hard parts (e.g. otoliths and scales) remains underutilized, despite some convincing examples of successful applications in the scientific literature. Among its most common applications in invasion biology, otolith chemistry has been used to identify natal origins, reconstruct migratory behaviour and assess mixed-stock structure. In this literature review, we provide a general overview of those previous applications but more importantly identify some gaps and obstacles to applications of otolith chemistry in invasion biology and suggest development for innovative applications, including use in wildlife forensic sciences and reconstruction of the early dynamics of invasions
Ce qu’il faut savoir sur le « lightboard »
Get PDFLa montée en popularité de la classe inversée et, plus récemment, la pandémie de COVID-19, ont mené plusieurs enseignantes et enseignants à élaborer des capsules vidéos à des fins pédagogiques. Le lightboard, une technologie apparue il y a sept ou huit ans, a d’ailleurs attiré l’attention de plusieurs et a gagné en popularité sur le Web et à l’intérieur de la communauté éducative. Nos collaborateurs de l'Université du Québec à Chicoutimi ont consulté la littérature scientifique sur le sujet. Voici un résumé de ce qu'ils ont appris
Evaluation of the Effect of Geomechanical Parameters and In Situ Stress on Tunnel Response Using Equivalent Mohr-Coulomb and Generalized Hoek-Brown Criteria
Get PDFThe generalized Hoek-Brown (GHB) failure criterion can estimate the rock mass parameters required for rock mechanics–related analyses such as numerical modeling in geomechanics. The determination of GHB parameters has been developed in the field of rock mechanics. Due to the wide use of the Mohr-Coulomb criterion and the lack of an existing relationship for determining its parameters for a rock mass, equivalent Mohr-Coulomb parameters (EMC) can be derived from the GHB. To determine the differences in the use of these two criteria, we analyzed the behavior of a deep circular tunnel in nine stress states for three metamorphic rocks recovered from the Canadian Shield from rock masses that present a very blocky structure. We carried out 241 simulations using the finite element code RS2 to assess the effect of the geological strength index (GSI), in situ stress, and rock type on the deviation of wall displacement, the number of yielded elements, and the differential stress obtained by the GHB and EMC parameters. A combination of low in situ stress and high GSI yielded similar results when using both failure criteria
Reconfigurable fully constrained cable-driven parallel mechanism for avoiding collision between cables with human
Get PDFProductivity can be increased by manipulators tracking the desired trajectory with some constraints. Humans as moving obstacles in a shared workspace are one of the most challenging problems for cable-driven parallel mechanisms (CDPMs) that are considered in this research. One of the essential primary issues in CDPM is collision avoidance among cables and humans in the shared workspace. This paper presents a model and simulation of a reconfigurable, fully constrained CDPM enabling detection and avoidance of cable–human collision. In this method, unlike conventional CDPMs where the attachment points are fixed, the attachment points on the rails can be moved (up and down on their rails), and then the geometric configuration is adapted. Karush–Kuhn–Tucker method is proposed, which focuses on estimating the shortest distance among moving obstacles (human limbs) and all cables. When cable and limbs are close to colliding, the new idea of reconfiguration is presented by moving the cable’s attachment point on the rail to increase the distance between the cables and human limbs while they are both moving. Also, the trajectory of the end effector remains unchanged. Some simulation results of reconfiguration theory as a new approach are shown for the eight-cable-driven parallel manipulator, including the workspace boundary variation. The proposed method could find a collision-free predefined path, according to the simulation results
Analyse de ruptures de cohérence évènementielle liées à l’emploi des connecteurs dans des textes de rédacteurs fonctionnels québécois francophones
Get PDFSans formation spécialisée en rédaction, des adultes utilisent leurs habiletés rédactionnelles en tant qu’étudiants, chercheurs d’emploi, employés ou entrepreneurs. Nous les appelons rédacteurs fonctionnels. Ces derniers publient leurs textes sur un blogue, dans un magazine ou dans un livre édité. Ces textes font souvent l’objet d’une révision linguistique. Au moment d’en effectuer la lecture, les réviseurs doivent parfois relire des passages pour saisir la relation entre des informations. Cette difficulté de lecture semble provoquée parfois par l’absence d’un connecteur, parfois par l’emploi d’un connecteur qui ne permet pas au lecteur d’identifier une relation vraisemblable entre les évènements. Les connecteurs sont des outils linguistiques servant à marquer les relations (ex. cause, restriction, but). Leur présence, bien qu’elle ne soit pas toujours requise, et leur emploi judicieux contribuent à faire en sorte que l’arrimage des énoncés au niveau évènementiel soit réussi. Or, dans certains cas, l’absence ou l’emploi d’un connecteur fait en sorte que le lecteur doit déployer un grand effort cognitif pour identifier cette relation entre les énoncés. Ces phénomènes engendrent une rupture de cohérence au niveau évènementiel. Dans ce mémoire, nous avons voulu comprendre les conditions dans lesquelles la cohérence au niveau évènementiel peut être perturbée par l’absence ou l’emploi plus ou moins adéquat de connecteurs. Pour ce faire, nous avons analysé 18 textes rédigés par 12 rédacteurs fonctionnels québécois francophones. Il ressort de notre analyse que la compétence des rédacteurs de notre corpus, en ce qui a trait à l’emploi des connecteurs, est très inégale. Si des ruptures ont été observées dans 12 textes (d’une à huit ruptures par texte), il reste que six textes ne présentent aucune rupture. Nos résultats font état de 41 ruptures, dont 33 résultent de l’absence d’un connecteur. De ce nombre, 13 ruptures touchent l’articulation de l’addition et 9, l’articulation de la conclusion