93 research outputs found
Trematominae and Artedidraconinae: contrasted mitogenome evolution for two Antarctic radiations
Cellular respiration has been widely studied in Antarctic teleost fishes because of their peculiar adaptations to an extreme environment. In parallel mitochondrial sequence markers have become highly popular for molecular systematics. However, there are few whole mitochondrial genome sequences published, and none available for some of the subfamilies. Here, we present two large mitogenome datasets including most species and multiple sequences for many species of two subfamilies, Trematominae and Artedidraconinae (Duhamel et al. 2014). These include two highly diverse but very different adaptative radiations, with contrasting divergence dates, morphological polymorphism, and habitat dominance. The sampling is based on a well identified, extensive collection resulting from the 2008 CEAMARC survey and the subsequent REVOLTA surveys in Terre Adélie (IPEV), already DNA barcoded and sequenced in previous studies. The mitogenome sequences for these two subfamilies differ in composition, gene order, and relative divergence of mitochondrial markers, with strong, taxon-specific biases like very high C contents in some regions. The gene order change provides a synapomorphy for the subfamily Trematominae and an interesting development in teleost mitogenomes. The complete Artedidraconinae mitogenomes provide a much higher amount of variable sites (approx*30), while previous sequence datasets were plagued by low informativeness (Lecointre et al. 2011). As already established on single mitochondrial genes, intraspecific variability is lower than interspecific variability within each subfamily, however interspecific variability in Artedidraconinae is lower or similar to intraspecific variability in Trematominae. This expanded dataset confirms the unusual evolution of the mitochondrial coded sequences involved in the cellular respiration in Antarctic Nototheniidae, as well as the usefulness of complete mitochondrial genomes for their systematics. The two level multiplexing (Timmermans et al. 2010) and next generation sequencing of long PCR amplicons (following Hinsinger et al. 2015) is efficient to obtain large mitogenomic datasets representative of both inter- and intraspecific variability, key to the understanding of mitochondrial evolution and a step closer to resolving the relationships among these taxa.RECTO (Refugia and Ecosystem Tolerance in the Southern Ocean, BR/154/A1/RECTO
Erg-O: ergonomic optimization of immersive virtual environments
Interaction in VR involves large body movements, easily inducing fatigue and discomfort. We propose Erg-O, a manipulation technique that leverages visual dominance to maintain the visual location of the elements in VR, while making them accessible from more comfortable locations. Our solution works in an open-ended fashion (no prior knowledge of the object the user wants to touch), can be used with multiple objects, and still allows interaction with any other point within user's reach. We use optimization approaches to compute the best physical location to interact with each visual element, and space partitioning techniques to distort the visual and physical spaces based on those mappings and allow multi-object retargeting. In this paper we describe the Erg-O technique, propose two retargeting strategies and report the results from a user study on 3D selection under different conditions, elaborating on their potential and application to specific usage scenarios
A Deletion in Exon 9 of the LIPH Gene Is Responsible for the Rex Hair Coat Phenotype in Rabbits (Oryctolagus cuniculus)
The fur of common rabbits is constituted of 3 types of hair differing in length and diameter while that of rex animals is essentially made up of amazingly soft down-hair. Rex short hair coat phenotypes in rabbits were shown to be controlled by three distinct loci. We focused on the âr1â mutation which segregates at a simple autosomal-recessive locus in our rabbit strains. A positional candidate gene approach was used to identify the rex gene and the corresponding mutation. The gene was primo-localized within a 40 cM region on rabbit chromosome 14 by genome scanning families of 187 rabbits in an experimental mating scheme. Then, fine mapping refined the region to 0.5 cM (Zâ=â78) by genotyping an additional 359 offspring for 94 microsatellites present or newly generated within the first defined interval. Comparative mapping pointed out a candidate gene in this 700 kb region, namely LIPH (Lipase Member H). In humans, several mutations in this major gene cause alopecia, hair loss phenotypes. The rabbit gene structure was established and a deletion of a single nucleotide was found in LIPH exon 9 of rex rabbits (1362delA). This mutation results in a frameshift and introduces a premature stop codon potentially shortening the protein by 19 amino acids. The association between this deletion and the rex phenotype was complete, as determined by its presence in our rabbit families and among a panel of 60 rex and its absence in all 60 non-rex rabbits. This strongly suggests that this deletion, in a homozygous state, is responsible for the rex phenotype in rabbits
A Deletion in Exon 9 of the LIPH Gene Is Responsible for the Rex Hair Coat Phenotype in Rabbits (Oryctolagus cuniculus)
The fur of common rabbits is constituted of 3 types of hair differing in length and diameter while that of rex animals is essentially made up of amazingly soft down-hair. Rex short hair coat phenotypes in rabbits were shown to be controlled by three distinct loci. We focused on the âr1â mutation which segregates at a simple autosomal-recessive locus in our rabbit strains. A positional candidate gene approach was used to identify the rex gene and the corresponding mutation. The gene was primo-localized within a 40 cM region on rabbit chromosome 14 by genome scanning families of 187 rabbits in an experimental mating scheme. Then, fine mapping refined the region to 0.5 cM (Zâ=â78) by genotyping an additional 359 offspring for 94 microsatellites present or newly generated within the first defined interval. Comparative mapping pointed out a candidate gene in this 700 kb region, namely LIPH (Lipase Member H). In humans, several mutations in this major gene cause alopecia, hair loss phenotypes. The rabbit gene structure was established and a deletion of a single nucleotide was found in LIPH exon 9 of rex rabbits (1362delA). This mutation results in a frameshift and introduces a premature stop codon potentially shortening the protein by 19 amino acids. The association between this deletion and the rex phenotype was complete, as determined by its presence in our rabbit families and among a panel of 60 rex and its absence in all 60 non-rex rabbits. This strongly suggests that this deletion, in a homozygous state, is responsible for the rex phenotype in rabbits
Gait disorders in the elderly and dual task gait analysis: a new approach for identifying motor phenotypes
A spill over effect of entrepreneurial orientation on technological innovativeness:an outlook of universities and research based spin offs
partially_open5siBy shifting towards Romerâs (Am Econ Rev 94:1002â1037, 1986) economy and so the spread of knowledge economy, universities started to adopt a collaborative approach with their entrepreneurial ecosystem. They turn out to be risk taker, autonomous, proactive, competitive, and innovative. In a nutshell, they are entrepreneurial oriented with the aim to generate new innovative ventures, known as research-based spin offs. Doubly, this has induced an improvement of technology transfer and the degree of entrepreneurship in the current knowledge economy. However there still is a paucity of studies on the spill over effect of entrepreneurial orientated universities and research-based spin off on technology transfer need to be more explored. Therefore, the article investigates the link between entrepreneurial orientation and such spill overs by offering an outlook of two universities and two research-based spin offs in the United Kingdom. The scope is to provide a deep view of technological innovativeness in a research context, entrepreneurial oriented. Our research suggests that entrepreneurial attitude has become an imperative to succeed in the context where British institutions currently operate. Entrepreneurship brings the necessary technological innovation to the university and its students, which results in better positioning of the university at national and international levels, with the subsequent impact on their ability to attract not only new students and academics but also funding to conduct their research.openScuotto, Veronica; Del Giudice, Manlio; Garcia-Perez, Alexeis; Orlando, Beatrice; Ciampi, FrancescoScuotto, Veronica; Del Giudice, Manlio; Garcia-Perez, Alexeis; Orlando, Beatrice; Ciampi, Francesc
ProblÚmes généraux de la fatigue oligocyclique
Centre d'Essais AĂ©ronautique de Toulouse
AprÚs avoir situé, sur une courbe d'endurance, le domaine de la fatigue oligocyclique, on analyse, d'un point de vue mécanique, les différents paramÚtres dont dépend la durée de vie dans ce domaine :
Gait instability measured by dual task gait test and leukoaraiosis.
International audienceObjective.â Gait unsteadiness is considered as the first step of major health concerns such as fall and dementia. Gait dysfunction has to be measured under dual task gait test (DTGT). The aim of this study was to investigate the relationships between DTGT and brain magnetic resonance imaging (MRI).Material and methods.â Data were collected through a Gait Instability Network including DTGT. Twenty-five patients aged less than 76 years old were tested (age: 71 ± 5 years, F: 8, M: 17, MMSE: 28 ± 2).Methods.â The assessment includes five successive steps: auto questionnaires, nurse evaluation, clinical balance tests, cognitive tests, medical examination, and DTGT. Gait analysis was provided by a three-axis accelerometer (Locometrix), three variables were selected: walking speed (WS), stride frequency (SF) and stride regularity index (SR). The Dual Task (DT) consists in walking and backward counting one by one from fifty. MRI including cortex trophycity, hippocampal Scheltens score, and age-related white matter changes (ARWMC) was performed under blind condition.Results.â Under DT condition, each gait variable decreases significantly. WS: from1.13 ± 0.24 to 0.98 ± 0.23 m/s (P = 0.02), SF: from 0.91 ± 0.09 to 0.79 ± 0.13 Hz (P < 0.001), SR: from 211 ± 51 to 160 ± 60 dimensionless (P < 0.002). Out of 25 patients, three had a vestibular disorder, one had post-stroke effects. No clinical explanation can be found for 21 patients other than hippocampal atrophy (Scheltens score 1.4 ± 0.6), and/or leukoaraiosis (ARWMC score: 4.3 ± 4.3).Discussion.â These results illustrate the interest of measuring not only walking speed and stride regularity, but also stride frequency under DTGT, and raise the question of the role of leukoaraiosis in gait instabilit
Dual task gait test and rehabilitation in the elderly.
International audienceObjective.â Gait rehabilitation in the elderly is usually focused on motor function. Recently complex motor-cognitive training has been reported more efficient to improve gait rehabilitation [1]. The rational is based on the interrelationship between cognition and motor function, which can be assessed by the dual-task (DT) paradigm [2]. The aim of this study was to investigate the implication of a dual task gait test (DTGT) in gait rehabilitation.Material.â Data were collected from outpatient's gait instability consultations including DTGT. Fifty-six patients were tested (age: 75±7years, F: 27, M: 29).Method.â Patients performed a reference single walking and an attention-demanding task while walking. DT consists in walking and backward counting one by one from fifty. Gait analysis was provided by a three-axis accelerometer (Locometrixâą). We computed the evolution of walking speed (WS) and stride regularity index (SR) between the single and the dual walking tasks.Results.â According to the evolution of WS and SR with an interval of±15%, two major different sub-groups were identified (P<0.0001). Subgroup 1: (21 patients) WS and SR remained constant. Subgroup 2: (33 patients), 19 decreased both WS and SR, 14 decreased SR but no change of WS. Two patients were out of these two subgroups, there was an increase of SR (magnet effect) but no change of WS.Discussion.â Gait rehabilitation programs can be tailored according to the results of a DTGT thanks to information about changes in velocity and regularity, which can be linked to the balance between motor and cognitive therapies
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