University of Quebec at Rimouski
Rimouski, Canada

The Université du Québec à Rimouski is a public university located in Rimouski, Quebec, Canada. Founded in 1969 as a satellite campus of the Université du Québec, UQAR provides access to higher education for the people of Bas-Saint-Laurent and the Gaspé Peninsula. It is the furthest north of any university in Québec. UQAR's programs include multidisciplinary research in marine science, regional development, and nordicity. Approximately 6,500 students attend the university. While most UQAR students are from eastern Québec, students also enroll from the countries of the Francophonie. Over 40,000 students have graduated since it opened in 1969. Wikipedia.

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Barka N.,University of Quebec at Rimouski
International Journal of Advanced Manufacturing Technology | Year: 2017

This paper presents the sensitivity study applied to spur gear heated by induction-heating process by exploring the effect of machine parameters on the hardness profile. The main process parameters, including the power (kW), the heating time (s), and the generator frequency (kHz) are the basic parameters that affect greatly the hardness and ultimately the mechanical performances. This research is made possible by simulation results obtained by coupling electromagnetic field and heat transfer. In order to complete the analysis, three stages are required; first, a Comsol 2D model was built considering the material properties and the machine parameters. Second, the surface temperatures and the case depths are deeply analyzed with the variation of the machine parameters. The relationship between the imposed current density in the coil and the power provided to the heated part is also determined. Finally, the sensitivity of hardness profile with the machine parameters variation was investigated using various statistical tools. © 2017 Springer-Verlag London

Boulangeat I.,CNRS Alpine Ecology Laboratory | Gravel D.,University of Quebec at Rimouski | Thuiller W.,CNRS Alpine Ecology Laboratory
Ecology Letters | Year: 2012

Although abiotic factors, together with dispersal and biotic interactions, are often suggested to explain the distribution of species and their abundances, species distribution models usually focus on abiotic factors only. We propose an integrative framework linking ecological theory, empirical data and statistical models to understand the distribution of species and their abundances together with the underlying community assembly dynamics. We illustrate our approach with 21 plant species in the French Alps. We show that a spatially nested modelling framework significantly improves the model's performance and that the spatial variations of species presence-absence and abundances are predominantly explained by different factors. We also show that incorporating abiotic, dispersal and biotic factors into the same model bring new insights to our understanding of community assembly. This approach, at the crossroads between community ecology and biogeography, is a promising avenue for a better understanding of species co-existence and biodiversity distribution. © 2012 Blackwell Publishing Ltd/CNRS.

Heon J.,University of Quebec at Rimouski | Arseneault D.,University of Quebec at Rimouski | Parisien M.-A.,Natural Resources Canada
Proceedings of the National Academy of Sciences of the United States of America | Year: 2014

Boreal ecosystems and their large carbon stocks are strongly shaped by extensive wildfires. Coupling climate projections with records of area burned during the last 3 decades across the North American boreal zone suggests that area burned will increase by 30-500% by the end of the 21st century, with a cascading effect on ecosystem dynamics and on the boreal carbon balance. Fire size and the frequency of large-fire years are both expected to increase. However, how fire size and time since previous fire will influence future burn rates is poorly understood, mostly because of incomplete records of past fire overlaps. Here, we reconstruct the length of overlapping fires along a 190-km-long transect during the last 200 y in one of the most fire-prone boreal regions of North America to document how fire size and time since previous fire will influence future fire recurrence. We provide direct field evidence that extreme burn rates can be sustained by a few occasional droughts triggering immense fires. However, we also show that the most fire-prone areas of the North American boreal forest are resistant to high burn rates because of overabundant young forest stands, thereby creating a fuel-mediated negative feedback on fire activity. These findings will help refine projections of fire effect on boreal ecosystems and their large carbon stocks.

Cloutier R.,University of Quebec at Rimouski | Cloutier R.,CNRS Geosciences Laboratory of Rennes
Seminars in Cell and Developmental Biology | Year: 2010

One of the properties of fossils is to provide unique ontogenies that have the potential to inform us of developmental patterns and processes in the past. Although fossilized ontogenies are fairly rare, size series of relatively complete specimens for more than 90 fish species have been documented in the literature. These fossilized ontogenies are known for most major phylogenetic groups of fishes and have a broad stratigraphic range extending from the Silurian to the Quaternary with a good representation during the Devonian. Classically, size series have been studied in terms of size and shape differences, where subsequently allometric changes were used as indicators of heterochronic changes in Paleozoic placoderms and sarcopterygians. Quantitative analyses of fossilized ontogenies of dipnoans have been interpreted in terms of morphological integration and fluctuating asymmetry. Recently, reconstructed sequences of ossification have been used to identify recurrent patterns of similar development in actinopterygians and sarcopterygians in order to infer phenotypic developmental modularity and saltatory pattern of development. Phylogenetic and temporal landmarks are put forward for some of the major developmental patterns in the evolution of fishes. © 2009 Elsevier Ltd. All rights reserved.

Gravel D.,University of Quebec at Rimouski | Guichard F.,McGill University | Hochberg M.E.,Montpellier University
Ecology Letters | Year: 2011

The contribution of deterministic and stochastic processes to species coexistence is widely debated. With the introduction of powerful statistical techniques, we can now better characterise different sources of uncertainty when quantifying niche differentiation. The theoretical literature on the effect of stochasticity on coexistence, however, is often ignored by field ecologists because of its technical nature and difficulties in its application. In this review, we examine how different sources of variability in population dynamics contribute to coexistence. Unfortunately, few general rules emerge among the different models that have been studied to date. Nonetheless, we believe that a greater understanding is possible, based on the integration of coexistence and population extinction risk theories. There are two conditions for coexistence in the presence of environmental and demographic variability: (1) the average per capita growth rates of all coexisting species must be positive when at low densities, and (2) these growth rates must be strong enough to overcome negative random events potentially pushing densities to extinction. We propose that critical tests for species coexistence must account for niche differentiation arising from this variability and should be based explicitly on notions of stability and ecological drift. © 2011 Blackwell Publishing Ltd/CNRS.

Agency: European Commission | Branch: FP7 | Program: CP-FP | Phase: SPA.2013.1.1-06 | Award Amount: 2.92M | Year: 2013

SWARP will develop downstream services for sea ice and waves forecast in the Marginal Ice Zone (MIZ) in the Arctic. Waves in ice are one of the most hazardous phenomena for vessels and industrial activities in the polar seas, but there are presently no services providing any information about either the waves themselves or their effects on the ice state (in particular the distribution of ice floe sizes). The monitoring and forecasting systems developed in SWARP aim to become operational by the middle of the project, filling a gap in the present marine core and downstream services of GMES. A waves-in-ice model will be first validated then included in the forecasting services provided downstream of MyOcean (Arctic sea ice forecast) and as part of Prvimer (global wave forecasts). In addition to wave and sea ice forecast models, the project will develop satellite observation methods for waves in ice and other ice properties in the MIZ such as ice concentration, ice types, ice thickness, ice drift and ice edge configuration. Existing and new satellite observing systems, especially SAR, optical and altimeter data, will be utilized for retrieval of waves and other ice properties in the MIZ. The project will be exploited operationally using data from future GMES satellites such as Sentinel-1. The project will integrate the new met-ocean services in state-of-the-art services for onboard navigation and shore-based contingency planning.

Magozzi S.,UK National Oceanography Center | Calosi P.,University of Quebec at Rimouski
Global Change Biology | Year: 2014

Predicting species vulnerability to global warming requires a comprehensive, mechanistic understanding of sublethal and lethal thermal tolerances. To date, however, most studies investigating species physiological responses to increasing temperature have focused on the underlying physiological traits of either acute or chronic tolerance in isolation. Here we propose an integrative, synthetic approach including the investigation of multiple physiological traits (metabolic performance and thermal tolerance), and their plasticity, to provide more accurate and balanced predictions on species and assemblage vulnerability to both acute and chronic effects of global warming. We applied this approach to more accurately elucidate relative species vulnerability to warming within an assemblage of six caridean prawns occurring in the same geographic, hence macroclimatic, region, but living in different thermal habitats. Prawns were exposed to four incubation temperatures (10, 15, 20 and 25 °C) for 7 days, their metabolic rates and upper thermal limits were measured, and plasticity was calculated according to the concept of Reaction Norms, as well as Q10 for metabolism. Compared to species occupying narrower/more stable thermal niches, species inhabiting broader/more variable thermal environments (including the invasive Palaemon macrodactylus) are likely to be less vulnerable to extreme acute thermal events as a result of their higher upper thermal limits. Nevertheless, they may be at greater risk from chronic exposure to warming due to the greater metabolic costs they incur. Indeed, a trade-off between acute and chronic tolerance was apparent in the assemblage investigated. However, the invasive species P. macrodactylus represents an exception to this pattern, showing elevated thermal limits and plasticity of these limits, as well as a high metabolic control. In general, integrating multiple proxies for species physiological acute and chronic responses to increasing temperature helps providing more accurate predictions on species vulnerability to warming. © 2014 John Wiley & Sons Ltd.

Anthropogenic disturbances have been demonstrated to affect animal behavior, distribution, and abundance, but assessment of their impacts on fitness-related traits has received little attention. We hypothesized that human activities and infrastructure cause a decrease in the individual performance of preys because of anthropogenically enhanced predation risk. We evaluated the impacts of commercial logging and road networks on the fitness of a large herbivore known to be sensitive to human disturbance: the forest-dwelling woodland caribou (Rangifer tarandus caribou). For 8 consecutive years (2004-2011) we monitored 59 individuals using GPS telemetry in the Charlevoix region of Québec, Canada. We also used Very High Frequency telemetry locations collected on 28 individuals from 1999-2000. We related habitat selection of adult caribou at various spatio-temporal scales to their probability of dying from predation, and to indices of their reproductive success and energy expenditure. The probability that adult caribou died from predation increased with the proportion of recent disturbances (including cutblocks ≤ 5 years old) in their annual home range. The respective effects of increasing paved and forestry road densities depended upon the overall road density within the home range of caribou. At a finer scale of 10 to 15 days before their death, caribou that were killed by a predator selected for recent disturbances more than individuals that survived, and avoided old mature conifer stands. The home range area of caribou increased with road density. Finally, the composition of the home range of females had no effect on their reproductive success. We show that human activities and infrastructure may influence the individual performance of large prey species in highly managed regions. We outline the need to consider the full set of impacts that human development may have on threatened animal populations, with particular emphasis on predator-prey relationships and population dynamics.

Legagneux P.,University of Quebec at Rimouski
Biology letters | Year: 2013

Behavioural responses can help species persist in habitats modified by humans. Roads and traffic greatly affect animals' mortality not only through habitat structure modifications but also through direct mortality owing to collisions. Although species are known to differ in their sensitivity to the risk of collision, whether individuals can change their behaviour in response to this is still unknown. Here, we tested whether common European birds changed their flight initiation distances (FIDs) in response to vehicles according to road speed limit (a known factor affecting killing rates on roads) and vehicle speed. We found that FID increased with speed limit, although vehicle speed had no effect. This suggests that birds adjust their flight distance to speed limit, which may reduce collision risks and decrease mortality maximizing the time allocated to foraging behaviours. Mobility and territory size are likely to affect an individuals' ability to respond adaptively to local speed limits.

Munro D.,University of Quebec at Rimouski | Blier P.U.,University of Quebec at Rimouski
Aging Cell | Year: 2012

The deleterious reactive carbonyls released upon oxidation of polyunsaturated fatty acids in biological membranes are believed to foster cellular aging. Comparative studies in mammals and birds have shown that the susceptibility to peroxidation of membrane lipids peroxidation index (PI) is negatively correlated with longevity. Long-living marine molluscs are increasingly studied as longevity models, and the presence of different types of lipids in the membranes of these organisms raises questions on the existence of a PI-longevity relationship. We address this question by comparing the longest living metazoan species, the mud clam Arctica islandica (maximum reported longevity=507year) to four other sympatric bivalve molluscs greatly differing in longevity (28, 37, 92, and 106year). We contrasted the acyl and alkenyl chain composition of phospholipids from the mitochondrial membranes of these species. The analysis was reproduced in parallel for a mix of other cell membranes to investigate whether a different PI-longevity relationship would be found. The mitochondrial membrane PI was found to have an exponential decrease with increasing longevity among species and is significantly lower for A. islandica. The PI of other cell membranes showed a linear decrease with increasing longevity among species and was also significantly lower for A. islandica. These results clearly demonstrate that the PI also decreases with increasing longevity in marine bivalves and that it decreases faster in the mitochondrial membrane than in other membranes in general. Furthermore, the particularly low PI values for A. islandica can partly explain this species' extreme longevity. © 2012 The Authors. Aging Cell © 2012 Blackwell Publishing Ltd/Anatomical Society of Great Britain and Ireland.

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