Search results for "Locomotion"
showing 10 items of 201 documents
Balance control in aging: improvements in anticipatory postural adjustments and updating of internal models
2015
International audience; Postural stability of older subjects can be estimated during orthostatic equilibrium. However, dynamic equilibrium is also important to investigate risks of fall. It implies different interpretations of measures given by force plates. Same dependant variables (e.g. center of pressure displacement) cannot be interpreted the same ways depending of the type of equilibrium that is investigated. In particular, sways increases during dynamic equilibrium and before movement execution may reflect an improvement of feedforward control.
Ankle and knee extensor muscle effort during locomotion in young and older athletes : Implications for understanding age-related locomotor decline
2019
AbstractAge-related reduction in muscle force generation capacity is similarly evident across different lower limb muscle groups, yet decline in locomotor performance with age has been shown to depend primarily on reduced ankle extensor muscle function. To better understand why ageing has the largest detrimental effect on ankle joint function during locomotion, we examined maximal ankle and knee extensor force development during a two-leg hopping test in older and young men, and used these forces as a reference to calculate relative operating efforts for the knee and ankle extensors as participants walked, ran and sprinted. We found that, across locomotion modes in both age groups, ankle ex…
Intra-Nasally Administered Oligopeptide Lunasin Acts as a Possible Anti-Psychotic Agent in Mice Models
2019
Background and Objectives: Previously we have shown that synthetic lunasin, a 43 amino acid residue-containing peptide, after its central (intracisternal) administration in mice demonstrated antagonism against dopaminergic drug behavioural effects, indicating a putative antipsychotic/anti-schizophrenic profile of lunasin. The aims of the present studies were: to test whether lunasin would show an influence on the dopaminergic system after intranasal administration, and to examine the effect(s) of lunasin on serotonin and glutamatergic systems, which could play an essential role in antipsychotic action. Materials and Methods: Lunasin was administered intra-nasally at doses 0.1 and 1 nmol/mou…
Transitions in Herd Management of Semi-Domesticated Reindeer in Northern Finland
2008
In northern Finland, reindeer-herd management has experienced two major transitions: extensification of intensive herding, and development of supplementary/corral feeding in winter. The transitions were studied in six herding associations in different parts of the Finnish reindeer management area. It was suggested that intensive herding turns into more extensive forms as the reasons for intensive herding (predation, reindeer disappearing to foreign areas, protection of agricultural fields) gradually ceased to exist. The results of the study, based on interviews of elderly reindeer herders, were variable. In the three southern areas intensive herding changed to the free ranging system at the…
Guenon Radiation is Enriched by a New Species that Demonstrates an Evolutionary Complexity with Which we are yet to Become Familiar
2012
th September described this discovery to the scientific community (1). As is becoming increasingly frequent these days, given the high number of scientific articles, the media news reached us faster than the scientific information. The area known as TL2, a few hundred km as the crow flies south- west from the city of Kisangani, famous for its manufacturing, and important port on the Zaire river, is still uncontaminated and houses several important endemisms. This new species, studied in the area since 2007, on the basis of first sightings by the inhabitants of the zone and local hunters, has been named Cercopithecus lomamiensis. C.lomamiensis (CLO) is a tree-dweller and has been described i…
Factors influencing the distribution, abundance and nest-site selection of an endangered Egyptian vulture (Neophron percnopterus) population in Sicily
2003
Egyptian vulture (Neophrom percnopterus) breeds in Sicily and, in 22 years of monitoring, has shown a decline followed by a slight recovery. We used Generalised Linear Models to predict: (1) the distribution range, (2) the habitat selection within the range, (3) the quality (i.e., occupation rate, breeding success) of breeding sites. Some 60% of Sicily proved to be unsuitable, being either too densely forested and without cliffs for nesting, or too densely populated, along with intensive agriculture. The models converged, indicating that the pairs select a precise upland habitat where low cliffs, distant from urban areas, are surrounded by arboreal crops and Mediterranean vegetation. The va…
Improvement of balance in a 7-year-old child through a six-week learning programme
2018
Given that human beings are constantly subjected to equilibration processes, developing basic perceptual motor skills, especially balance, is important. The main purpose of this study is the validation of the tasks and the progression of activities that form the learning programme for balance development in a six-week didactic unit of 12 sessions (2 sessions per week), for 6 to 9 year old children (1st, 2nd, and 3rd grade of elementary school in Brazil). The changes in balance after applying the programme are also analysed through a new measuring protocol using baropodometry. Although the session was put into practice in a class of 28 children, data were extracted from a 7-year-old child. T…
Mildronate treatment improves functional recovery following middle cerebral artery occlusion in rats
2011
Mildronate (3-(2,2,2-trimethylhydrazinium) propionate) is an inhibitor of l-carnitine biosynthesis and an anti-ischemic drug. In the present study, we investigated the effects of mildronate in rats following focal cerebral ischemia. Male Wistar rats were subjected to transient occlusion of the middle cerebral artery (MCAO) for 90min, followed by the intraperitoneal administration of mildronate at doses of 100 and 200mg/kg 2h after reperfusion and then daily for an additional 14days. The beam-walking, rota-rod and cylinder tests were used to assess sensorimotor function, and vibrissae-evoked forelimb-placing and limb-placing tests examined responses to tactile and proprioceptive stimulation.…
A test of the effort equalization hypothesis in children with cerebral palsy who have an asymmetric gait.
2022
Healthy people can walk nearly effortlessly thanks to their instinctively adaptive gait patterns that tend to minimize metabolic energy consumption. However, the economy of gait is severely impaired in many neurological disorders such as stroke or cerebral palsy (CP). Moreover, self-selected asymmetry of impaired gait does not seem to unequivocally coincide with the minimal energy cost, suggesting the presence of other adaptive origins. Here, we used hemiparetic CP gait as a model to test the hypothesis that pathological asymmetric gait patterns are chosen to equalize the relative muscle efforts between the affected and unaffected limbs. We determined the relative muscle efforts for the ank…
Path Planning for Perception-Driven Obstacle-Aided Snake Robot Locomotion
2020
Development of snake robots have been motivated by the ability of snakes to move efficiently in unstructured and cluttered environments. A snake robot has the potential to utilise obstacles for generating locomotion, in contrast to wheeled robots which are unable to move efficiently in rough terrain. In this paper, we propose a local path planning algorithm for snake robots based on obstacle-aided locomotion (OAL). An essential feature in OAL is to determine suitable push-points in the environment that the snake robot can use for locomotion. The proposed method is based on a set of criteria for evaluating a path, and is a novel contribution of this paper. We focus on local path planning and…