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Presenters Genevieve Arsenault-Lapierre, PhD, Maxime Guillette, Alexandra Lemay-Compagnat, Louis Rochette, MSc, Victoria Massamba, MPH, Yves Couturier, PhD, Eric Maubert, Christine Fournier, Caroline Morin, Caroline Boudreau, Isabelle Vedel, MD, [...], Context: Providing context-specific information and fostering reflective practice is essential to support a learning health system. Regional health boards in Quebec, Canada, have the responsibility to ensure implementation of the Quebec Alzheimer's Plan (QAP) in primary, secondary, and tertiary care services but need support. As such, we have developed and disseminated regional portraits on dementia care. Objective: To describe the lesson learned and next steps on the development and presentations of regional portraits. Design: A multi-methods study with a participatory approach. Setting: Quebec, Canada. Population: Stakeholders (ministerial decision-maker and project managers, managers and clinicians from the 23 regional health board, and researchers/scientific advisors). Methods: We selected, with stakeholders, 9 indicators (prevalence, regular physician visits, emergency visits, and hospitalizations) and measured them in 2019-20. Also, we thematically analysed the last 3 years of ongoing QAP implementation evaluation reports and meetings. We combined these results to formulate, with stakeholders, key messages for each regional health board. Along with ministerial decision-maker and project managers, we presented these portraits to regional managers and clinicians. Real-time notes were taken using structured observation guide. A thematic analysis was performed. Results: The development of the portraits was facilitated by a strong and ongoing alliance between the stakeholders. Researchers and scientific advisors identified the most relevant data available; project managers ensured the formulated messages were meaningful to regional managers and clinicians; and policymakers ensured the collected data was useful to support the implementation of QAP. The regional managers and clinicians proposed ways to improve the portraits (i.e., adding indicators), and to regularly update and integrate these portraits into steering committees. Monitoring the indicators as precisely presents challenges, including regularly obtaining current data. Conclusion: This innovative project supports a learning health system for the care of persons with dementia. Specifically, it stimulates the emergence of regional and provincial innovations in dementia care to accomplish the implementation of the QAP, ensure its local appropriation and perpetuates sustainable transformed practices. Proposed solutions will guide the preparation of next iteration of regional portraits.

This paper describes research done on a new testing device including its laboratory test procedure; namely, a laboratory punching test for cementitious backfill materials that evaluates their excavatability with a pick. Three- dimensional and two-dimensional numerical studies using a finite element method were carried out according to calibrated parameters of the material obtained by triaxial tests. This made it possible to study the behavior of the backfill material under action induced by a tool (a pick) as well as to optimize the geometry of the punching test specimen. This paper provides detailed information and results for the experimental study of this laboratory test. Attention was particularly focused on energy relating to displacement as well as types of ruptures. The behavior of these types of materials was found to be greatly influenced by gravel in the material. Repeatability of the test was also studied. Finally, a method for this punching test of backfill materials is also provided. Key words: cement-treated materials, excavatability, impact energy, punching test, repeatability. Cet article decrit une recherche effectuee sur un nouvel appareil et la procedure d'essai de laboratoire correspondante, a savoir un essai de poin^onnement pour evaluer la facilite d'excavation a l'aide d'une pioche des materiaux hydrauliques de remblayage de tranchees. Des etudes tridimensionnelles et bidimensionnelles numeriques en utilisant une methode aux elements finis ont ete realisees avec les parametres materiaux calibres sur des essais triaxiaux. Cela a permis d'etudier le comportement des materiaux de remblayage dans le cadre de l'action induite par un outil (une pioche) ainsi que d'optimiser la geometrie de l'echantillon utilise dans l'essai de poin^onnement. Ce document fournit des informations detaillees et les resultats de l'etude experimentale de l'essai en laboratoire. L'attention a surtout ete portee sur l'energie necessaire aux enfoncements ainsi qu'au facies de ruptures. On a trouve que le comportement de ces types de materiaux est fortement influence par de granulats grossiers dans le materiau. La repetabilite de l'essai a egalement ete etudiee. Enfin, une methode pour cet essai de poin^onnement de materiaux de remblayage de tranchees est egalement fournie. [Traduit par la Redaction] Mots-cles: materiaux traites au ciment, facilite d'excavation, energie d'impact, essai de poin^onnement, repetabilite., Introduction Controlled low-strength materials (CLSMs) have the specificity of being self-leveling and have a nonconfined compressive strength lower than 8 MPa (ACI 2009). Used as backfill materials, they make it [...]

Four experiments contrasted the predictions of a general encoding-retrieval match hypothesis with those of a view claiming that the distinctiveness of the cue-target relationship is the causal factor in retrieval. In Experiments 1, 2, and 4 participants learned the relationships between 4 targets and trios of cues; in Experiment 3 there were 3 targets, each associated with a pair of cues. A learning phase was followed by a cued-recognition task where the correct target had to be identified based on 1 or more of the cues. The main performance measurement was response time. Learning was designed to lead to high accuracy so effects could be attributed to retrieval efficiency rather than to variations in encoding. The nature of the cues and targets was varied across experiments. The critical factor was whether each cue was uniquely associated with the to-be-recalled target. All experiments orthogonally manipulated (a) how discriminative--or uniquely associated with a target--each cue was and (b) the degree of overlap between the cues present during learning and those present at retrieval. The novel finding reported here is that increasing the encoding-retrieval match can hinder performance if the increase simultaneously reduces how well cues predict a target--that is, a cue's diagnostic value. Encoding-retrieval match was not the factor that determined the effectiveness of retrieval. Our findings suggest that increasing the encoding-retrieval match can lead to no change, an increase, or a decrease in retrieval performance. (Contains 6 tables and 3 figures.)

Human cytochrome P-450 epoxygenase enzymes metabolize eicosapentaenoic acid (EPA), an [omega]-3-polyunsaturated fatty acid (PUFA), and leads to the production of 17(18)-epoxyeicosatetraenoic acid, or 17(18)-EpETE. The aim of the present study was to delineate the mode of action of 17(18)-EpETE on human pulmonary artery (HPA) and distal bronchi. Isometric tension measurements demonstrated that 17(18)-EpETE induced concentration-dependent relaxing effects in pulmonary artery and airway smooth muscles. Iberiotoxin (IbTx) and glyburide (Glyb), known [BK.sub.Ca] and [K.sub.ATP] channel inhibitors, respectively, reversed the relaxation induced by 17(18)-EpETE on both tissues types. Microelectrode measurements showed that exogenous addition of 17(18)-EpETE hyperpolarized the membrane potential of HPA and bronchial smooth muscle cells. These induced electrophysiological effects were reversed by the addition of 10 nM IbTx and 10 [micro]M Glyb. Complementary experiments performed on human bronchi, using the planar lipid bilayer reconstitution technique, demonstrated that 17(18)-EpETE activated reconstituted BKca channels at low free [Ca.sup.2+] concentration. Moreover, in bronchi, the relaxing responses induced by 17(18)-EpETE were also related to reduced [Ca.sup.2+] sensitivity of the myofilaments, since free [Ca.sup.2+] concentration-response curves, performed on [beta]-escinpermeabilized cultured explants, were shifted toward higher [Ca.sup.2+]. Together, these results provide new insight into the mode of action of 17(18)-EpETE in lung tissues and highlight this eicosanoid as a potent modulator of tone on both HPA and distal bronchi in vitro, which may be of clinical relevance in the pathophysiology of pulmonary hypertension and airway diseases. 17(18)-eicosatetraenoic acid; membrane potential; potassium channels; isometric tension; relaxation

The aim of the present study was to provide a mechanistic insight into how 20-hydroxyeicosatetraenoic acid (20-HETE) relaxes distal human pulmonary arteries (HPAs). This compound is produced by to-hydroxylase from free arachidonic acid. Tension measurements, performed on either fresh or 1 day-cultured pulmonary arteries, revealed that the contractile responses to 1 [micro]M 5-hydroxytryptamine were largely relaxed by 20-HETE in a concentration-dependent manner (0.01-10 [micro]M). Iberiotoxin pretreatments (10 nM) partially decreased 20-HETE-induced relaxations. However, 10 [micro]M indomethacin and 3 [micro]M SC-560 pretreatments significantly reduced the relaxations to 20-HETE in these tissues. The relaxing responses induced by the eicosanoid were likely related to a reduced [Ca.sup.2+] sensitivity of the myofilaments since free [Ca.sup.2+] concentration ([[Ca.sup.2+]])-response curves performed on [beta]-escin-permeabilized cultured explants were shifted toward higher [[Ca.sup.2+]]. 20-HETE also abolished the tonic responses induced by phorbol-ester-dibutyrate (a PKC-sensitizing agent). Western blot analyses, using two specific primary antibodies against the PKC-potentiated inhibitory protein CPI-17 and its PKC-dependent phosphorylated isoform pCPI- 17, confirmed that 20-HETE interferes with this intracellular process. We also investigated the effect of 20-HETE on the activation of Rho-kinase pathway-induced [Ca.sup.2+] sensitivity. The data demonstrated that 20-HETE decreased U46619-induced [Ca.sup.2+] sensitivity on arteries. Hence, this observation was correlated with an increased staining of [p116.sup.Rip], a RhoA-binding protein. Together, these results strongly suggest that the 20-hydroxyarachidonic acid derivative is a potent modulator of tone in HPAs in vitro. 20-hydroxyeicosatetraenoic acid; calcium sensitivity; tension measurement

Airway smooth muscle (ASM) metabolizes arachidonic acid (AA) through various enzymatic pathways, including cytochrome P-450 (CYP-450) [omega]-hydroxylase, which leads to the production of 20-hydroxyeicosatetraenoic acid (20-HETE). The goal of this study was to delineate the mode of action of 20-HETE in human ASM cells. Isometric tension measurements demonstrated that 20-HETE induced a concentration-dependent relaxant effect in ASM on bronchi precontracted with either methacholine or AA. Relaxing effects of 20-HETE on resting tone were prevented by 10 nM iberiotoxin (IbTx), a [BK.sub.Ca] channel inhibitor. Microelectrode measurements showed that exogenous additions of 20-HETE (0.1-10 [micro]M) hyperpolarized the membrane potential of human ASM cells. This concentration-dependent electrophysiological effect induced by the eicosanoid was prevented by 10 nM IbTx. Complementary experiments, using the planar lipid bilayer reconstitution technique, demonstrated that 20-HETE activated reconstituted [BK.sub.Ca] channels at low free [Ca.sup.2+] concentrations. Together, these results indicate that 20-HETE-dependent activation of [BK.sub.Ca] channels is responsible for the hyperpolarization and controlled relaxation of ASM in human distal bronchi. 20-hydroxyeicosatetraenoic acid; organ culture; membrane potential

In exemplar models of categorization, the similarity between an exemplar and category members constitutes evidence that the exemplar belongs to the category. We test the possibility that the dissimilarity to members of competing categories also contributes to this evidence. Data were collected from two 2-dimensional perceptual categorization experiments, one with lines varying in orientation and length and the other with coloured patches varying in saturation and brightness. Model fits of the similarity-dissimilarity generalized context model were used to compare a model where only similarity was used with a model where both similarity and dissimilarity were used. For the majority of participants the similarity-dissimilarity model provided both a significantly better fit and better generalization, suggesting that people do also use dissimilarity as evidence.

The mechanical properties and [Ca.sup.2+] sensitivity of an organ-culture model derived from guinea pig airways have been examined. The cultured explants develop airway hyperresponsiveness to pharmacological agonists after 3-day culture, [...]

5-Oxo-ETE regulates tone of guinea pig airway smooth muscle via activation of [Ca.sup.2+] pools and Rho-kinase pathway. Am J Physiol Lung Cell Mol Physiol 287: L631-L640, 2004. First published April 16, 2004: 10.l152/ajplung.00005.2004.--5-Oxo-6,8,11,14-eicosatetraenoic acid (5-oxo-ETE) is a proinflammatory mediator, but its effects on airway smooth muscle (ASM) have never been assessed. Tension measurements performed on guinea pig ASM showed that 5-oxo-ETE induced sustained concentration-dependent positive inotropic responses (E[C.sub.50] = 0.89 [micro]M) of somewhat lower amplitude than those induced by carbamylcholine and the thromboxane [A.sub.2] (TX[A.sub.2]) agonist U-46619. Transient inotropic responses to 5-oxo-ETE were recorded in [Ca.sup.2+]-free medium, suggesting mobilization of intracellular [Ca.sup.2+]. Meanwhile, the sustained contraction, which required [Ca.sup.2+] entry, was partially blocked by I [micro]M nifedipine (an L-type [Ca.sup.2+] channel blocker) but relatively insensitive to 100 [micro]M [Gd.sup.3+]. The 5-oxo-ETE responses were also inhibited by indomethacin and SC-560 [a cyclo-oxygenase (COX-1) inhibitor] pretreatments but not by NS-398 (a selective COX-2 inhibitor). The contractile effects of 5-oxo-ETE on ASM were inhibited by the selective TX[A.sub.2] receptor (TP receptor) antagonist SQ-29548 (-75%) and by 2-(p-amylcinnamoyl) amino-4-chiorobenzoic acid pretreatment, a phospholipase [A.sub.2] inhibitor (-66%), suggesting that the major part of its effect is mediated by the release of TX[A.sub.2]. ASM responses to 5-oxo-ETE were also blocked by the Rho-kinase inhibitor Y-27632, which also partially inhibited the response to the TP receptor agonist U-46619, suggesting that the contractile response is due in part to [Ca.sup.2+] sensitization of ASM cell myofilaments. 5-oxo-eicosatetraenoic acid; isometric tension: membrane potential; calcium entry; transient receptor potential; Rho-kinase