Platanthera blephariglottis : une espèce indicatrice de l’intégrité écologique des tourbières ombrotrophes au Québec

Ce mémoire visait à déterminer si la platanthère à gorge frangée (Platanthera blephariglottis var. blephariglottis), une orchidée, est une espèce indicatrice de l’intégrité écologique des tourbières ombrotrophes. Les indicateurs d’intégrité écologique sont des outils indispensables pour évaluer efficacement les composantes d’un écosystème. Les résultats indiquent que l’abondance de la platanthère est fortement liée à l’indice de qualité floristique (FQAI). Le FQAI est aussi un excellent prédicateur de la présence de l’espèce, avec un taux de succès à 87%. D’autre part, l’abondance de l’orchidée est négativement affectée par les activités anthropiques et la matrice environnante. D’un point de vue descriptif, les habitats renfermant une grande abondance d’orchidées sont caractérisés par une faible microtopographie de surface et un recouvrement important de bryophytes et d’éricacées de petite taille. Globalement, ce mémoire a montré que la platanthère renferme un potentiel pour être indicatrice de l’intégrité écologique des tourbières ombrotrophes au Québec.The aim of this study was to evaluate whether White Fringed Orchid (Platanthera blephariglottis var. blephariglottis) can be used as an indicator of Sphagnum bog integrity. Ecological indicators of integrity are important tools as it is impossible to monitor efficiently all components of an ecosystem. Results indicate that White Fringed Orchid abundance is highly linked with floristic quality assessment index (FQAI). FQAI is also a good predictor of presence of the species, with an accuracy of 87%. On the other hand, orchid abundance is negatively affected by anthropogenic activities and the environmental matrix. Similarly, peatlands having low edge effect are characterized by higher orchid abundance than those more influenced by edges. From a descriptive perspective, high orchid abundance habitat is characterized by low surface microtopography, high bryophyte and small ericaceous covers. Globally, this study has shown that White Fringed Orchid has potential to evaluate ecological integrity in Sphagnum bogs in Québec

TRUNK MOTION DURING A HALF-MARATHON: THE IMPACT OF PERCEIVED FATIGUE ON MOTION STABILITY AND SMOOTHNESS

Our objective was to investigate the effects of acute fatigue on stability and smoothness of trunk motion during a half marathon. 13 recreational runners were fitted with a GNSS-IMU sensor on their chest. Every 10 minutes of the race, the participant pronounced their perceived fatigue, recorded by a smartphone attached to the arm. We divided the race into 8 equal segments, corresponding to one fatigue score per segment, and considered only level running. Based on mediolateral acceleration and running velocity (v), stability was characterized by spectral entropy, RMS of acceleration (RMSA), and autocorrelation between successive steps and strides; smoothness by jerk cost (JC), spectral arc length (SPARC), and inverse number of peaks (IPV) of v. Both RMSA and JC increased significantly shortly after race onset. RMSA increased significantly at a lower perceived fatigue level, while JC increased at a higher level. Whereas other measures did not change substantially, RMSA and JC showed a clear change with acute fatigue and also differentiated well between the five fastest and five slowest runners. With increasing perceived fatigue, both parameters showed a higher change for ‘slow’ group. This study highlights the loss of stability and smoothness in running due to acute fatigue and the importance of simultaneously measuring perceived fatigue and trunk biomechanics under real-world conditions

Sociologia clínica e saúde mental

The project “Recovery and life project” has a double objective: i. propose to the employees and residents of Maison Saint-Dominique (MSD - Montréal/Canadá), an in-depth work on his “family history and social trajectory”, under the guidance of clinical sociology, ii. develop an action research to evaluate this experiment as an alternative perspective on mental health, to be disseminated and compared other practices in the field of mental health. The article presents, in the first moment, the approach, its theoretical and methodological foundations. In the second moment, it reports the way in which the participants carried out the proposal and the perceived effects from their testimonies. The approach illustrates the interest in developing a clinic of complexity within the domain of mental health.Le projet “Rétablissement et projet de vie” a un double objectif: i. proposer aux intervenants et aux résidents de la Maison Saint-Dominique (MSD - Montréal/Canada), un travail approfondi sur leur “roman familial et trajectoire sociale”, dans l’orientation de la sociologie clinique; ii. développer une recherche-action pour évaluer cette expérimentation en tant qu’approche alternative en santé mentale, la diffuser et la confronter à d’autres pratiques dans le domaine de la santé mentale. Le texte qui suit présente, dans un premier temps, la démarche, ses soubassements théoriques et méthodologiques. Dans un deuxième temps, il rend compte de la façon dont les participants l’ont mis en œuvre et les effets perceptibles à partir de leurs témoignages. La démarche illustre l’intérêt de développer une clinique de la complexité dans le domaine de la santé mentale.Le projet “Rétablissement et projet de vie” a un double objectif: i. proposer aux intervenants et aux résidents de la Maison Saint-Dominique (MSD - Montréal/Canada), un travail approfondi sur leur “roman familial et trajectoire sociale”, dans l’orientation de la sociologie clinique; ii. développer une recherche-action pour évaluer cette expérimentation en tant qu’approche alternative en santé mentale, la diffuser et la confronter à d’autres pratiques dans le domaine de la santé mentale. Le texte qui suit présente, dans un premier temps, la démarche, ses soubassements théoriques et méthodologiques. Dans un deuxième temps, il rend compte de la façon dont les participants l’ont mis en œuvre et les effets perceptibles à partir de leurs témoignages. La démarche illustre l’intérêt de développer une clinique de la complexité dans le domaine de la santé mentale

D5.3 Studies on CLC-CCS deployment and infrastructure development

publishedVersio

Optical extinction in a single layer of nanorods

We demonstrate that almost 100 % of incident photons can interact with a monolayer of scatterers in a symmetrical environment. Nearly-perfect optical extinction through free-standing transparent nanorod arrays has been measured. The sharp spectral opacity window, in the form of a characteristic Fano resonance, arises from the coherent multiple scattering in the array. In addition, we show that nanorods made of absorbing material exhibit a 25-fold absorption enhancement per unit volume compared to unstructured thin film. These results open new perspectives for light management in high-Q, low volume dielectric nanostructures, with potential applications in optical systems, spectroscopy, and optomechanics

Dynamics of Bacterial Communities Mediating the Treatment of an As-Rich Acid Mine Drainage in a Field Pilot

Passive treatment based on iron biological oxidation is a promising strategy for Arsenic (As)-rich acid mine drainage (AMD) remediation. In the present study, we characterized by 16S rRNA metabarcoding the bacterial diversity in a field-pilot bioreactor treating extremely As-rich AMD in situ, over a 6 months monitoring period. Inside the bioreactor, the bacterial communities responsible for iron and arsenic removal formed a biofilm (“biogenic precipitate”) whose composition varied in time and space. These communities evolved from a structure at first similar to the one of the feed water used as an inoculum to a structure quite similar to the natural biofilm developing in situ in the AMD. Over the monitoring period, iron-oxidizing bacteria always largely dominated the biogenic precipitate, with distinct populations (Gallionella, Ferrovum, Leptospirillum, Acidithiobacillus, Ferritrophicum), whose relative proportions extensively varied among time and space. A spatial structuring was observed inside the trays (arranged in series) composing the bioreactor. This spatial dynamic could be linked to the variation of the physico-chemistry of the AMD water between the raw water entering and the treated water exiting the pilot. According to redundancy analysis (RDA), the following parameters exerted a control on the bacterial communities potentially involved in the water treatment process: dissolved oxygen, temperature, pH, dissolved sulfates, arsenic and Fe(II) concentrations and redox potential. Appreciable arsenite oxidation occurring in the bioreactor could be linked to the stable presence of two distinct monophylogenetic groups of Thiomonas related bacteria. The ubiquity and the physiological diversity of the bacteria identified, as well as the presence of bacteria of biotechnological relevance, suggested that this treatment system could be applied to the treatment of other AMD

Role of iron, light, and silicate in controlling algal biomass in subantarctic waters SE of New Zealand

Phytoplankton processes in subantarctic (SA) waters southeast of New Zealand were studied during austral autumn and spring 1997. Chlorophyll a (0.2–0.3 μg L−1) and primary production (350–650 mg C m−2 d−1) were dominated by cells 1 nmol kg−1, there was little evidence of Fe-stressed algal populations, and Fυ/Fm approached 0.60 at the STC. In addition to these trends, waters of SA origin were occasionally observed within the STC and north of the STC, and thus survey data were interpreted with caution. In vitro Fe enrichment incubations in SA waters resulted in a switch from flavodoxin expression to that of ferredoxin, indicating the alleviation of Fe stress. In another 6-day experiment, iron-mediated increases in chlorophyll a (in particular, increases in large diatoms) were of similar magnitude to those observed in a concurrent Si/Fe enrichment; ambient silicate levels were 4 μM. A concurrent in vitro Fe enrichment, at irradiance levels comparable to the calculated mean levels experienced by cells in situ, resulted in relatively small increases (approximately twofold) in chlorophyll a. Thus, in spring, irradiance and Fe may both control diatom growth. In contrast, during summer, as mean irradiance increases and silicate levels decrease, Fe limitation, Fe/Si colimitation, or silicate limitation may determine diatom growth

Finite Element Prediction of Elastic Recoil after Stent Implantation

Peer reviewed: YesNRC publication: Ye

A comparison of the seasonal movements of tiger sharks and green turtles provides insight into their predator-prey relationship

During the reproductive season, sea turtles use a restricted area in the vicinity of their nesting beaches, making them vulnerable to predation. At Raine Island (Australia), the highest density green turtle Chelonia mydas rookery in the world, tiger sharks Galeocerdo cuvier have been observed to feed on green turtles, and it has been suggested that they may specialise on such air-breathing prey. However there is little information with which to examine this hypothesis. We compared the spatial and temporal components of movement behaviour of these two potentially interacting species in order to provide insight into the predator-prey relationship. Specifically, we tested the hypothesis that tiger shark movements are more concentrated at Raine Island during the green turtle nesting season than outside the turtle nesting season when turtles are not concentrated at Raine Island. Turtles showed area-restricted search behaviour around Raine Island for ~3–4 months during the nesting period (November–February). This was followed by direct movement (transit) to putative foraging grounds mostly in the Torres Straight where they switched to area-restricted search mode again, and remained resident for the remainder of the deployment (53–304 days). In contrast, tiger sharks displayed high spatial and temporal variation in movement behaviour which was not closely linked to the movement behaviour of green turtles or recognised turtle foraging grounds. On average, tiger sharks were concentrated around Raine Island throughout the year. While information on diet is required to determine whether tiger sharks are turtle specialists our results support the hypothesis that they target this predictable and plentiful prey during turtle nesting season, but they might not focus on this less predictable food source outside the nesting season