Alien Registration- Bergeron, Emile (Auburn, Androscoggin County)

https://digitalmaine.com/alien_docs/30872/thumbnail.jp

Flow Structure and Channel Stability at the Site of a Deep Scour Hole, Mackenzie Delta, Canada

Unusually deep scour holes in distributary channels of the Mackenzie Delta are of concern for oil and gas resource development, particularly with respect to buried pipeline crossings. Surveys of one such hole, carried out in 1985 and 1992, indicated vertical stability and slight lateral movement. The present study examines how the hole may have changed by the mid-2000s and documents the complex local velocity field and related bed material properties. Small discrepancies between isobaths of different years suggest a dynamic stability that involves short-term fluctuations in erosion and deposition. This suggestion was corroborated by detailed measurements of the highly three-dimensional velocity field, which revealed major eddy structures and flow reversals that help maintain sizeable velocity magnitudes despite low mean velocities. The composition of the bed material suggests cohesive behaviour, but the literature indicates a range of critical shear stresses that spans two orders of magnitude. The more probable lower end of this range is consistent with the observed dynamic stability of the scour hole.Des fosses d’affouillement exceptionnellement profondes se trouvant dans les effluents du delta du Mackenzie risquent de poser des problèmes en matière de mise en valeur des ressources pétrolières et gazières, surtout en ce qui a trait aux pipelines enfouis. Selon les levés d’une de ces fosses effectués en 1985 et en 1992, cette fosse serait verticalement stable et aurait un léger mouvement latéral. La présente étude se penche sur la façon dont la fosse pourrait avoir changé une fois rendu vers le milieu des années 2000 et documente le champ de vitesse local complexe de même que les propriétés des matériaux de fond connexes. De petits écarts entre les isobathes de différentes années laissent entrevoir une stabilité dynamique assortie de fluctuations à court terme sur le plan de l’érosion et de la déposition. Cette suggestion a été corroborée à l’aide de mesures détaillées du champ de vitesse hautement tridimensionnel, qui a révélé d’importantes structures à grands tourbillons et des écoulements de retour qui favorisent le maintien d’intensités de vitesse appréciables malgré des vélocités moyennes faibles. Bien que la composition des matériaux de fond suggère un comportement cohésif, la documentation indique une gamme de contraintes de cisaillement critique qui s’étend sur deux ordres de grandeur. Le bas de cette gamme plus probable est conforme à la stabilité dynamique observée à l’égard de la fosse d’affouillement

Alien Registration- Bergeron, Emile (Sanford, York County)

https://digitalmaine.com/alien_docs/3698/thumbnail.jp

Alien Registration- Bergeron, Emile (Sanford, York County)

https://digitalmaine.com/alien_docs/3698/thumbnail.jp

Alien Registration- Bergeron, Emile (Auburn, Androscoggin County)

https://digitalmaine.com/alien_docs/30872/thumbnail.jp

Brook trout passage performance through culverts

Culverts can restrict access to habitat for stream-dwelling fishes. We used PIT telemetry to quantify passage performance of > 1000 wild brook trout attempting to pass 13 culverts of Quebec under a range of hydraulic and environmental conditions. Several variables influenced passage success, including complex interactions between physiology and behavior, hydraulics, and structural characteristics. The probability of successful passage was greater through corrugated metal culverts than through smooth ones, particularly among smaller fish. Trout were also more likely to pass at warmer temperatures, but this effect diminished above 15°C. Passage was impeded at higher flows, through culverts with steep slopes and those with deep downstream pools. This study provides insight on factors influencing brook trout capacity to pass culverts as well as a model to estimate passage success under various conditions, with an improved resolution and accuracy over existing approaches. It also presents methods that could be used to investigate passage success of other species, with implications for connectivity of the riverscape.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Absence of predictable long-term molecular effect of ulipristal acetate (UPA) on the endometrium

International audienceRESEARCH QUESTION: What are the effects of ulipristal acetate (UPA) on the expression of endometrial proliferation and maturation markers?DESIGN: A total of 45 endometrium-containing blocks of hysterectomy samples from non-menopausal women with a diagnosis of moderate to severe symptoms of uterine fibroids: 14 women operated on at the end of a 3-month course of UPA; four women who had discontinued UPA treatment 1-12 months before surgery; 27 control unexposed samples (14 in the proliferative and 13 in the secretory phase). Immunohistochemical staining of Ki67, vascular endothelial growth factor-receptor 2 (VEGFR2), oestradiol receptor, progesterone receptor, interleukin-15 (IL-15), indoleamin-2,3-dioxygenase (IDO) and C-C motif chemokine ligand-2 (CCL2) markers were analysed in both endometrial compartments and layers.RESULTS: Under UPA, oestradiol receptor and progesterone receptor expression is similar to the proliferative phase in both layers, although with a decrease in cell proliferation. IL-15, IDO and CCL2 expressions are similar to the proliferative phase, suggesting a progesterone-antagonist effect of UPA. VEGFR2 staining suggests a trend to a mixed agonist-antagonist effect. No significant difference is observed in the post-UPA proliferative phase group compared with the control group in both layers of the endometrium.CONCLUSION: The effect of 3-month UPA treatment is mostly progesterone receptor antagonist-like. After treatment is discontinued, there are no signs of any long-term effects of this molecule on endometrial proliferation and maturation. Therefore, UPA may be administered to women willing to conceive in the short term without consequences for further implantation