882 research outputs found
The population structure of roundnose grenadier (Coryphaenoides rupestris) in southwestern Norway
Ocean circulation, bathymetric barriers, and ecological processes can hinder the dispersal of marine fishes and thus generate sub-populations. The present study investigated the population structure of a benthopelagic fish, Coryphaenoides rupestris, from three Norwegian fjords and two coastal sites using eight microsatellite DNA markers. Genetic analyses revealed significant population genetic structure across the study area (FST = 0.0297, P < 0.001) and temporal stability in the Skagerrak. There was evidence of highly isolated sub-populations, as shown by significant pairwise differences in tests of genic differentiation and analysis of molecular variance (AMOVA), high inbreeding coefficients (FIS), high homozygosity, and low genetic diversity. Small-scale, within-fjord population structuring was also found in Lustrafjord. Mantel tests revealed a strong effect of isolation by distance and isolation by depth (bottom depth) and a possible effect of bottom temperature. Significant differences in fish condition were found between sites and included length-weight relationships (Analysis of Covariance (ANCOVA): F = 8.249, df = 7, P < 0.001), Hepatosomatic Index (HSI; GLM: F = 252.48, df = 3, P < 0.001) and Gonadosomatic Index (GSI; GLM: F = 15.91, df = 3, P < 0.001). In conclusion, population structuring in C. rupestris along the Norwegian coast seems to be influenced by distance, bathymetric barriers like bottom depth and fjord sills, and differences in fish condition indicate possible differences in environmental conditions between sites. Coryphaenoides rupestris is an overfished species that has been redlisted as critically endangered. Based on the present findings, stock management should consider each of the sub-populations independently, and not depend on recovery through recruitment from neighbouring sub-populations.Master's Thesis in BiologyBIO39
Population genomics of a critically endangered data-deficient elasmobranch, the blue skate Dipturus batis
Doctoral thesis (PhD) - Nord University, 2021publishedVersio
Does vaterite otolith deformation affect post-release survival and predation susceptibility of hatchery-reared juvenile Atlantic salmon?
publishedVersio
Assessment of MISR and MODIS cloud top heights through inter-comparison with a back-scattering lidar at SIRTA
One year of back-scattering lidar cloud boundaries and optical depth were analysed for coincident inter-comparison with the latest processed versions of the NASA-TERRA MISR stereo and MODIS CO2-slicing operational cloud top heights. Optically thin clouds were found to be accurately characterised by the MISR cloud top height product as long as no other cloud was present at lower altitude. MODIS cloud top heights were generally found within the cloud extent retrieved by lidar; agreement improved as cloud optical depth increased and when CO2-slicing was the only technique used for the retrieval. The difference between Lidar and MISR cloud top heights was found to lie between −0.1 and 0.4 km for low clouds and between 0.1 and 3.1 km for high clouds. The difference between Lidar and MODIS cloud top heights was found to lie between −1.2 and 1.5 km for low clouds and between −1.4 and 2.7 km for high clouds
A Domain-Specific Language for Multitask Systems, Applying Discrete Controller Synthesis
International audienceWe propose a simple programming language, called Nemo, specific to the domain of multitask real-time control systems, such as in robotic, automotive, or avionics systems. It can be used to specify a set of resources with usage constraints, a set of tasks that consume them according to various modes, and applications sequencing the tasks. We automatically obtain an application-specific task handler that correctly manages the constraints (if there exists one), through a compilation-like process including a phase of discrete controller synthesis. This way, this formal technique contributes to the safety of the designed systems, while being encapsulated in a tool that makes it usable by application experts. Our approach is based on the synchronous modelling techniques, languages, and tools
A domain-specific language for task handlers generation, applying discrete controller synthesis
We propose a simple programming language, called Nemo, specific to the domain of multi-task real-time embedded systems, such as in robotic, automotive or avionics systems. It can be used to specify a set of resources with usage constraints, a set of tasks that consume them according to various modes, and applications sequencing the tasks. We obtain automatically an application-specific task handler that correctly manages the constraints (if there exists one), through a compilation-like process including a phase of discrete controller synthesis. This way, this formal technique contributes to the safety of the designed systems, while being encapsulated in a tool that makes it usable by end-users and application experts. Our approach is based on the synchronous modelling techniques, languages and tools
A formal approach for the synthesis and implementation of fault-tolerant industrial embedded systems
International audienceWe demonstrate the feasibility of a complete workflow to synthesize and implement correct-by-construction fault tolerant distributed embedded systems consisting of real-time periodic tasks. Correct-by-construction is provided by the use of discrete controller synthesis (DCS), a formal method thanks to which we are able to guarantee that the synthesized controlled system guarantees the functionality of its tasks even in the presence of processor failures. For this step, our workflow uses the Heptagon domain specific language and the Sigali DCS tool. The correct implementation of the resulting distributed system is a challenge, all the more since the controller itself must be tolerant to the processor failures. We achieve this step thanks to the libDGALS real-time library (1) to generate the glue code that will migrate the tasks upon processor failures, maintaining their internal state through migration, and (2) to make the synthesized controller itself fault-tolerant
Revisiting the STEC Testing Approach: Using espK and espV to Make Enterohemorrhagic Escherichia coli (EHEC) Detection More Reliable in Beef
Current methods for screening Enterohemorrhagic Escherichia coli (EHEC) O157 and non-O157 in beef enrichments typically rely on the molecular detection of stx, eae, and serogroup-specific wzx or wzy gene fragments. As these genetic markers can also be found in some non-EHEC strains, a number of “false positive” results are obtained. Here, we explore the suitability of five novel molecular markers, espK, espV, ureD, Z2098, and CRISPRO26:H11 as candidates for a more accurate screening of EHEC strains of greater clinical significance in industrialized countries. Of the 1739 beef enrichments tested, 180 were positive for both stx and eae genes. Ninety (50%) of these tested negative for espK, espV, ureD, and Z2098, but 12 out of these negative samples were positive for the CRISPRO26:H11 gene marker specific for a newly emerging virulent EHEC O26:H11 French clone. We show that screening for stx, eae, espK, and espV, in association with the CRISPRO26:H11 marker is a better approach to narrow down the EHEC screening step in beef enrichments. The number of potentially positive samples was reduced by 48.88% by means of this alternative strategy compared to the European and American reference methods, thus substantially improving the discriminatory power of EHEC screening systems. This approach is in line with the EFSA (European Food Safety Authority) opinion on pathogenic STEC published in 2013
Revisiting the STEC Testing Approach: Using espK and espV to Make Enterohemorrhagic Escherichia coli (EHEC) Detection More Reliable in Beef
Current methods for screening Enterohemorrhagic Escherichia coli (EHEC) O157 and non-O157 in beef enrichments typically rely on the molecular detection of stx, eae, and serogroup-specific wzx or wzy gene fragments. As these genetic markers can also be found in some non-EHEC strains, a number of “false positive” results are obtained. Here, we explore the suitability of five novel molecular markers, espK, espV, ureD, Z2098, and CRISPRO26:H11 as candidates for a more accurate screening of EHEC strains of greater clinical significance in industrialized countries. Of the 1739 beef enrichments tested, 180 were positive for both stx and eae genes. Ninety (50%) of these tested negative for espK, espV, ureD, and Z2098, but 12 out of these negative samples were positive for the CRISPRO26:H11 gene marker specific for a newly emerging virulent EHEC O26:H11 French clone. We show that screening for stx, eae, espK, and espV, in association with the CRISPRO26:H11 marker is a better approach to narrow down the EHEC screening step in beef enrichments. The number of potentially positive samples was reduced by 48.88% by means of this alternative strategy compared to the European and American reference methods, thus substantially improving the discriminatory power of EHEC screening systems. This approach is in line with the EFSA (European Food Safety Authority) opinion on pathogenic STEC published in 2013
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