NCube/papyrus huggingface dataset:
Défaillance cardiaque et mécanismes de protection et réparation du myocarde

Congestive heart failure (CHF) remains a leading cause of mortality in the developed world. There are more than 400,000 diagnosed cases of this pathology in Canada. Despite the numerous treatment options available for patients presenting with left ventricular dysfunction, the evolution of this population is still dismal. Stem cell transplantation is a potential approach to repopulate the injured myocardium, to treat heart failure, and to restore cardiac function. However, the exact mechanisms underlying the beneficial effects of this approach remain to be elucidated. The hypotheses of this thesis are the following: 1) the long-term evolution of patients undergoing coronary artery bypass graft surgery is still poor, even when considering the use of new innovative surgical strategies such as off-pump coronary revascularization; 2) the intracoronary injection of concentrated biologically active factors secreted by stem cells can achieve early protection of the ischemic myocardium and preserve heart function; and 3) the bone marrow/heart interaction in a critical axis is involved in chronic myocardial repair following persistent ischemic injury.

Keyphrases: Effet paracrine, Heart failure, Coronary artery revascularization, Cellular therapy, Myocardial regeneration, Paracrine effect, Bone marrow-heart axis, Progenitor cells
Writing : a concrete strategy to facilitate the integration of conflicting identities into the self

More and more, people must learn to integrate new identities in their self-concept, which is often the source of identity conflicts. To reduce these identity conflicts, previous research suggests that high levels of identity integration increases psychological wellbeing (Amiot, de la Sablonnière, Terry & Smith, 2007; Benet-Martinez & Haritatos,2005; de la Sablonnière, Amiot, Sadykova, Cardenas, & Gorborukova, 2010). So far, no strategy to promote identity integration was suggested. In parallel, the action of writing about a negative experience demonstrates that writing helps organize and structure ideas while enhancing psychological well-being (Lyubomirsky, Sousa & Dickerhoof, 2006; Pennebaker & Graybeal, 2001; Pennebaker & Seagal, 1999; Smyth, 1998). Thus, we hypothesize that writing will facilitate the integration of conflicting identities into the self. Studies 1 and 2 reveal that writing about identity conflicts, as compared to writing about a neutral topic or no writing, is associated with superior levels of psychological well-being only for participants scoring high on identity integration. Studies 3 and 4 confirm that several writing sessions using clearer writing instructions helped participants to increase both levels of identity integration and psychological well-being regardless of the initial level of identity integration. Analyses of participants’ written content were performed to deepen our understanding.

Keyphrases: identity, integration, conflict resolution, writing, psychological well-being
La communication de la douleur et de l'incapacité au sein des couples dont l'un des partenaires souffre de douleur persistante

In the past, it has been shown that pain communication, through the display of pain behaviours, is related to self-reported disability and pain chronicity. However, few studies have investigated the link between pain perception in couples and the chronic trajectory of individuals suffering from persistent pain.  In the current thesis, three studies were conducted in order to understand the factors that are involved in pain communication in couples where one partner suffers from persistent pain. The first study aimed to validate a francophone version of the Pain Disability Index (PDI), a questionnaire, developed to assess disability associated with persistent pain. As expected, the results showed that this version of the PDI replicate the factorial structure of the original version of the PDI and showed a good reliability and validity. Another study was conducted with couples where one partner suffers from persistent pain to investigate the correlates of empathic accuracy, explore the relation between pain-related empathic accuracy and different variables associated with adaptational outcomes for chronic pain patients and their spouses, and explore the relation between pain-related empathic accuracy and relational variables. The results generally suggest that empathic accuracy is associated with negative outcomes for the patient, and might not be an important correlate of marital satisfaction. Finally, a last study was conducted to understand the influence of couple concordance of catastrophizing on the display of pain behaviours and on the perception of pain and disability in a physically demanding task. Results revealed that high catastrophizing pain participants, who were in a relationship with a low catastrophizing spouse, displayed more pain behaviours than all other groups. These findings suggest that high catastrophizing chronic pain persons might need to increase the ‘volume’ of pain communication in order to compensate for low catastrophizing spouses’ tendency to underestimate the severity of their pain experience. In brief, since the display of pain behaviours is related to self-reported disability of chronic pain persons, it is possible that any situation that contributes to the increase of pain behaviours, will also contribute to a higher disability level. Therefore, from a clinical perspective, interventions that lead the spouse to engage in active listening and to respond with validating statements, could reduce the amount of pain behaviours and possibly have an impact on the disability level of chronic pain persons.

Keyphrases: empathic accuracy, catastrophizing
Évaluation du potentiel de séquestration de carbone dans le sol de cultures intensives sur courtes rotations de saules dans le sud du Québec

Over the last ten years, many hectares of short-rotation willow coppice (SRWC) have been established on abandoned agricultural lands in southern Quebec (Canada). However, few studies were conducted to determine if these changes from a conventional crop to SRWC of willows would affect the soil carbon dynamic. A preliminary paired-site study was conducted to assess the impact of this land-use conversion on soil carbon stocks and dynamics shortly after they were established (1-year and 2-year) at one site and after multiple rotations (9-year) at another site. Apart from the total soil organic carbon pool, two labile carbon pools were investigated: the hot-water extractable carbon (HWC) pool and the amino sugars (AS) pool. Willow establishment and exploitation for nine years did not bring any changes in total organic carbon compared to an abandoned hay culture. The mature SRWC displayed a redistribution of TSOC in the vertical soil profile. We also measured a higher proportion of AS, compared to other plots on the same site, in total organic carbon under the 1-year-old SRWC; especially the proportion in AS of fungi origin that theorically decrease with perturbation intensity. Proportion of AS was also elevated under 2-year-old SRWC. A possible interpretation is that establishment-linked perturbations did not shift carbon dynamic toward an increased mineralization. The mature willow plantation exhibited depletion of HWC and the more labile amino sugar (muramic acid) in the deeper soil layer (20-40cm). This case study shows that conversion from an abandoned hay culture to a SRWC did not create a carbon sink. It was also found that the 9- year old willow plantation contained higher TSOC and had better soil quality than an adjacent short-term no-till crop rotation culture.

Keyphrases: Séquestration de carbone, Carbon sequestration, Willow, Hot water extractable carbon, Amino sugars, Carbon pools
Elenchos standard : le cas négligé de l’Alcibiade

For about thirty years, studies on refutation, or elenchus (ἔλεγχος), have multiplied. This interest has been stimulated by the publication of an article by Gregory Vlastos, The Socratic Elenchus, in which an original and controversial theory of the elenchus is presented. It is interesting to note, however, that Vlastos rejected Plato’s Greater Alcibiades from his study, judging it inauthentic, even though the arguments presented by the supporters of its inauthenticity are rather unconvincing. In this master’s thesis, a detailed analysis of Vlastos’ article and the Greater Alcibiades will be conducted. Special attention will be given to the following questions: what the Greater Alcibiades can tell us on the elenchus? Can it tell us something new? If so, will this new knowledge confirm or invalidate the theories of Vlastos or the traditional conception of Socratic refutation? The first chapter focuses on the thesis presented in the last version of the article “The Socratic Elenchus”, published in 1994 in Socratic Studies.  A critical summary of the article shall then be presented in addition to an exposition of the reactions of various commentators. The second chapter will focus on the Greater Alcibiades. An analysis of this dialogue, more precisely of the elenchus, is conducted as well as a comparison of Vlastos’ principal thesis with the results of our analysis. This master’s thesis will show that the Greater Alcibiades provides a description of the elenchus that does not concur with Vlastos’ conception.

Keyphrases: Vlastos, Alcibiade, Philosophy, Plato, Vlastos, Alcibiades, Elenchus, Refutation, Dialectic
Électrofilage de complexes de polymères

This work has allowed to show that electrospinning, as well as electrospraying, are easy and efficient methods for preparing complexes between polymers and small molecules. Most complex preparation methods yield inhomogeneous mixtures because of the kinetically favoured crystallization of small molecules. An inhomogeneous mixture can be very difficult to characterize. In this work, electrospinning was used for the first time to obtain nanofibres of complexes between poly(ethylene oxide) (PEO) and NaSCN (PEO-NaSCN) as well as between PEO and hydroquinone. Electrospraying was used to obtain a complex between polycaprolactone (PCL) and urea. Electrospinning was not possible for the PCL-urea system because the solubility was not sufficient to attain the minimal viscosity required for electrospinning. Electrospraying can thus be used as a complementary technique to electrospinning, making this approach applicable to a much wider range of systems. The systems were characterized by infrared spectroscopy (FT-IR), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and microscopy (optical and scanning electronic microscopy).

Keyphrases: Complexes, Polycaprolactone, Electrospinning, Electrospraying, Complex, Nanofibres, Poly(ethylene oxide), Polycaprolactone
Calmodulin/KCa3.1 channel interactions as determinant to the KCa3.1 Ca2+ dependent gating : theoretical and experimental analyses

The Ca2+ sensitivity of the voltage-insensitive calcium activated potassium channel of intermediate conductance KCa3.1 is conferred by calmodulin (CaM) constitutively bound to the membrane-proximal region of the channel intracellular C-terminus.  A study was performed to investigate the nature of the residues involved in the CaM/KCa3.1 interactions and determine how these interactions could modulate the channel gating properties. A 3D-structure of the KCa3.1/CaM complex was first generated by homology modeling with MODELLER using as template the crystal structure of SK2.2/CaM  complex  (PDB: 1G4Y). The resulting structural model of KCa3.1 plus CaM predicts that  the segment L361-S372 in KCa3.1 should be responsible for the Ca2+-dependent binding of the channel to the CaM-N lobe, with residues L361 and Q364  facing residues E45, E47 and D50 of CaM.  To test this model residues in L361-S372 segment were substituted by Cys and the action of  MTSET+ (positive charged) and MTSACE (neutral charged) measured on channel activity.  Inside-out patch clamp recordings showed that the binding of the charged MTSET+ reagent to the Q364C mutant resulted in a strong current increase, an effect not seen with the neutral MTSACE. The mutations E45A and E47A in CaM  prevented the current increase initiated by MTSET+ on the Q364C mutant.  A single channel analysis confirmed that the binding of MTSET+ to Q364C caused an increase in the channel open probability by a destabilization of the channel closed state. Altogether, our results are compatible with the formation of ionic bonds between the positively charged Cys-MTSET+ complex at position 364 in KCa3.1 and the negatively charged E45 and E47 residues in CaM, and confirm that an electrostatic stabilization of the CaM/KCa3.1 interactions can lead to an increase in the channel open probability at saturating Ca2+.

Keyphrases: Homology modeling, Potassium channels, KCa3.1, KCa3.1, Electrophysiologie, Electrophysiology, Calmodulin (CaM)
Structure quaternaire des récepteurs de chimiokines CXCR4 et CCR2 et interaction avec leurs effecteurs

G protein-coupled receptors (GPCRs) are a diverse family of membrane proteins capable of responding to a large number of extracellular stimuli including photons, odorant molecules and hormones. In addition to this diversity, it has been shown that GPCRs form specific protein:protein interactions, multiplying the signalling possibilities of each of these receptors. With the ability to diminish, to potentiate or even generate new signalling pathways, the oligomeric association of GPCRs plays an important role in generating this diversity. The use of bioluminescence resonance energy transfer (BRET), which allows the detection of interactions among proteins, has revealed numerous associations between GPCRs. During this thesis, tools have been developed that effectively combine BRET with protein complementation assays (PCA) with the goal of determining if interactions between GPCRs could involve more than two receptors. The results show that the chemokine receptors CXCR4 and CCR2 form both homo and hetero tetramers, and that the activation of a dimer of CCR2 can modulate the conformation of a CXCR4 dimer through a transreceptor conformational change. Negative cooperativity of ligand binding has previously been demonstrated between CXCR4 and CCR2 in CD4+ T lymphocytes endogenously expressing the receptors, confirming the biological validity of this interaction. The data presented also suggests that these complexes can engage the effector proteins Gαi and β- arrestin 2, indicating that they represent a functional form of the receptors. Furthermore, we have confirmed that each receptor of the CXCR4-CCR2 heterodimer is implicated in the engagement of effectors during the activation of CCR2. An additional level of complexity in GPCR-promoted signaling exists in their capacity to couple of multiple G proteins. Binding of stromal cell-derived factor-1 (SDF-1) to CXCR4 is known to promote T lymphocyte migration through a Gαi-dependent signalling pathway. In addition to this mechanism, we have demonstrated that breast cancer cell migration can initiated by a coupling of CXCR4 to the Gα13-Rho pathway, leading to the formation of metastases in distant organs. Finally, a novel level of GPCR regulation was revealed through the study of CXCR4 phosphorylation following its activation, which leads to the desensitization of the receptor and the engagement of β-arrestin-dependent signalling pathways. It appears that the desensitization of calcium signalling is mediated through the phosphorylation of CXCR4 by the GPCR kinases (GRKs) GRK2 and GRK6 and the recruitment of β-arrestin 2, whereas GRK3, GRK6 and β-arrestin 1 potentiate the activation of extracellular regulated kinase (ERK1/2). We also propose that the phosphorylation of the far C-terminal tail of CXCR4 is required for the interaction between the receptor and β-arrestin.

Keyphrases: CXCR4, CCR2, G protein coupled receptor, bioluminescence resonance energy transfer (BRET), CXCR4, CCR2, tetramer, protein complementation assay (PCA)
Rôle de la molécule CD47 dans l’homéostasie du système immunitaire

Previous work in the laboratory have demonstrated the role of CD47 in the function of dendritic cells and in the induction of regulatory T cells in humans. Here, we show that the ubiquitous self-marker CD47 selectively regulates DC, but not T and B cell trafficking across lymphatic vessels and endothelial barriers in vivo. Competitive DC migration assays and active immunization with myeloid DCs demonstrate that CD47 expression is required on DCs but not on the endothelium and not vice and versa for efficient DC trafficking and T-cell responses. This migratory defect correlates with the quasi-disappearance of splenic marginal zone DCs in non manipulated CD47-deficient mice. Our data reveal that CD47 on DCs is a critical factor in controlling migration and efficient initiation of the immune response.  Mutual or reciprocal regulation exists between DCs and Tregs. For instance, DCs efficiently induce Tregs in vivo. We here examine how CD47 deficiency that selectively decrease myeloid DCs impact on Treg homeostasis.  We here show that CD47 expression, selectively regulated CD103+Foxp3+ Treg homeostasis. The proportion of effector/memory-like (CD44highCD62Llow) CD103+ Foxp3+ Tregs rapidly augmented with age in CD47-deficient mice (CD47-/-) as compared with age-matched control littermates. Yet, the percentage of quiescent (CD44lowCD62Lhigh) CD103-Foxp3+ Tregs remained stable. Thus, sustained CD47 expression throughout life is critical to avoid an excessive expansion of CD103+ Tregs that may overwhelmingly inhibit Ag specific T cell responses. DCs and Tregs are closely regulated to maintain the balance between protective immunity and tolerance. When that balance is broken, several diseases such as cancer, infectious diseases and autoimmune diseases may develop. Our ultimate goal is to understand how CD47 regulates DCs and Tregs function. Manipulation of the two cells types may open to the door to unexplored therapeutic avenues.

Keyphrases: Migration, CD47, CD103, Sirp-alpha, Migration, CD103, Sirp-alpha, Dendritic cells, CD47, Regulatory T cells
Novel approaches to the synthesis and treatment of cathode
materials for lithium-ion batteries

We have developed a novel approach to the synthesis of cathode materials for lithium-ion batteries, based on the thermal decomposition of urea. Mixed metal hydroxides (NixMnxCo(1-2x)(OH)2), x = 0.00 to 0.50, were prepared and subsequently used as precursor for lithiated mixed metal oxide (LiNixMnxCo(1-2x)O2). These materials along with lithium iron phosphate (LiFePO4) are being considered as cathode materials for the next generation of lithium-ion batteries. We have also developed new post-synthetic treatments on the hydroxides in order to enhance the morphology, which would result in improved electrode properties. The novelty of this thesis is that for the first time mixed metal hydroxides for use as precursors for lithium mixed oxides have been prepared via a uniform precipitation technique from solution. In addition, we have proposed new treatments techniques towards the more traditional synthesis method for mixed metal hydroxides. The results obtained from these two methods are summarized within two articles that were recently submitted to peer-reviewed journals. Within this thesis, all materials were analyzed with X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal gravimetric analysis (TGA) and electrochemical measurements. The electrochemical performance (capacity vs cycle number) of the cathode materials were tested galvanostatically.

Keyphrases: Lithium-ion battery, cathode material, Pile lithium-ion, novel synthetic approaches, treatments for mixed metal hydroxides and lithium iron phosphate
From "This is my body" to the Church in the twenty-first century: the Last Supper as the decisive moment and criterion of a renewed ecclesiology

Unmistakable symptoms indicate some very serious problems in the Church. While they also plague other denominations and religions, this work deals specifically with the Roman Catholic Church. The most significant symptoms include a drastic decline in participation in religious activity, such as Sunday eucharistic celebrations, especially among younger people, a near-catastrophic shortage of ordained priests, and a loss of the prestige and influence of the teaching authority of the Church. The intensity of these symptoms varies in different areas of the world, but statistical data show that they are spreading. Many of the problems are due to the incredibly fast changes occurring in the world and the apparent inability of the Church to adapt to them, especially in its strong attachment to neo-scholastic thinking and Tridentine tradition. Exclusive reliance on a tradition developed four hundred years ago is unsuitable in a rapidly and radically changing environment. Appropriate changes are necessary in practically all areas of the life of the Church. For these to be successful and also true to the nature of the Church, tradition alone is an insufficient guide. Based on the statement of the encyclical Ecclesia de Eucharistia, the “decisive moment in her [the Church] taking shape was certainly the institution of the Eucharist in the Upper Room,” this thesis returns as closely as possible to the interpretation given to the words of Jesus, this is my body, when they were first uttered. On the evidence available, it can be asserted that the defining characteristics of the Church, given by these words, are agape, unity and service. This must be the guiding principle of changes to be implemented. It is on this basis that the areas in which changes are needed and the aspects to be changed are described. These include liturgy, sacraments, catechesis, mystagogy, theology, the structure and governance of the Church, its teachings, and evangelisation. Within these areas serious effort must be made to properly prepare those involved in the changes and to focus on the pre-eminent requirement of making agape, unity and service the active and obvious principle that governs the Church.

Keyphrases: Agape, Agape, Amour, Bread, Eucharist, Jesus, Service, Service, Theology, Tradition, Tradition, Unity, Church, Community
Les habiletés olfactives des aveugles de naissance : organisation anatomo-fonctionnelle et aspects comportementaux

It is generally acknowledged that people blind from birth develop supra-normal sensory abilities in order to compensate for their visual deficit. While extensive research has been done on the somatosensory and auditory modalities of the blind, information about their sense of smell remains scant. The goal of this study was therefore to understand olfactory processing in the blind at the behavioral and the neuroanatomical levels. Since blind individuals use their remaining senses in a compensatory way to assess their environment and since the olfactory system is highly plastic, it is likely to be susceptible to changes similar to those observed for tactile and auditory modalities. We used psychophysical testing and functional magnetic resonance imaging (fMRI) to investigate the neuronal substrates responsible for odor processing. Our data showed that blind subjects had a lower odor detection threshold compared to the sighted. However, no group differences were found for odor discrimination and odor identification. Interestingly, the OAS revealed that blind participants scored higher for odor awareness. Our fMRI data revealed stronger BOLD responses in the right lateral orbitofrontal cortex, bilateral medio-dorsal thalamus, right hippocampus and left occipital cortex in the blind participants during an odor detection task. We conclude that blind subjects rely more on their sense of smell than the sighted in order to assess their environment and to recognize places and people. This is the first demonstration that the visual cortex of the blind can also be recruited by odorants, thus adding new evidence to its multimodal function.

Keyphrases: olfaction, blindness, odor awareness, cross-modal plasticity, fMRI