Gravitational-wave tail effects to quartic non-linear order

Gravitational-wave tails are due to the backscattering of linear waves onto the space-time curvature generated by the total mass of the matter source. The dominant tails correspond to quadratic non-linear interactions and arise at the one-and-a-half post-Newtonian (1.5PN) order in the gravitational waveform. The "tails-of-tails", which are cubic non-linear effects appearing at the 3PN order in the waveform, are also known. We derive here higher non-linear tail effects, namely those associated with quartic non-linear interactions or "tails-of-tails-of-tails", which are shown to arise at the 4.5PN order. As an application, we obtain at that order the complete coefficient in the total gravitational-wave energy flux of compact binary systems moving on circular orbits. Our result perfectly agrees with black-hole perturbation calculations in the limit of extreme mass ratio of the two compact objects.Comment: 32 pages, no figure, matches with published versio

Conditions socio-environnementales pour la réhabilitation de la biodiversité ordinaire

International audienceOur paper presents the state of our research on the socio-environmental conditions for the rehabilitation of common biodiversity-CLEVERT Program. The participation of local populations, on a district scale, in the public debates about the maintenance or the restoration of functional ecosystems is now an imperative of public policies. The originality of the program is based on a long term presence on the field, an easy implementation of the protocols and sessions of participative cartography. Our purpose /objective is to understand on what social configurations are based the conservation projects and to assess if the awareness of ecological issues is better taken into account in a context of local empowerment. Our paper has four sections: summarized account of ethno ecological data of the three fields, correlation of social and environmental data, analysis of the favorable factors regarding the co-construction of knowledge, mutual relations amongst the disciplines involved (anthropology, ecology and geography). MOTS CLES Sciences participatives, biodiversité ordinaire, échelle communale, populations locales.Notre exposé est un état des recherches portant sur le programme « conditions socio-environnementales pour la réhabilitation de la biodiversité ordinaire » – CLEVERT. La participation des populations locales, à l'échelle communale, aux débats publics portant sur le maintien ou la restauration d'écosystèmes fonctionnels, est désormais incontournable. L'originalité du programme repose sur le fort investissement des équipes scientifiques, la clarté des protocoles, la cartographie participative. L'objectif est de comprendre de quelles configurations sociales dépendent les projets de conservation et de vérifier si l'empowerment des populations locales favorise la prise en compte des enjeux écologiques. La communication comporte 4 sections : présentation des données ethnoécologiques des trois terrains ; corrélation des données sociales et environnementales ; analyse des facteurs favorables à la co-construction des savoirs ; rapports mutuels des disciplines impliquées (anthropologie, écologie et géographie)

Pompey – La céramique de poêle du château de l'Avant-Garde

Identifiant de l'opération archéologique : F1354200100065 Date de l'opération : 2001 (PT) Une quantité exceptionnelle de tessons de céramiques de poêle a été mise au jour lors des fouilles menées entre 1981 et 1989 au château de l'Avant-Garde à Pompey, érigé à partir de 1314 et démantelé en 1635. Ces travaux ont été réalisés avec un manque de méthode préjudiciable à l'étude du mobilier, puisque aucun relevé stratigraphique n'a été effectué, ce qui a compliqué la datation des très nombreux obj..

Reduced analgesic effect of acupuncture-like TENS but not conventional TENS in opioid treated patients

Abstract : Evidence from recent animal studies indicates that the analgesic effect of low frequency TENS is reduced in opioid tolerant animals. The aim of the present study was to compare the analgesic effect of conventional (high frequency) and acupuncture-like (low frequency) TENS between a group of opioid treated patients and a group of opioid-naive patients in order to determine if this cross-tolerance effect is also present in humans. Twenty-three chronic pain patients (11 who took opioids and 12 who did not) participated in the study. Participants were assigned in a randomized cross-over design to receive alternately conventional and acupuncture-like TENS. There was a significant reduction in pain during and after conventional TENS when compared to baseline for both the opioid and non-opioid group (p.09). The reduced analgesic effect of acupuncture-like TENS in opioid treated patients is coherent with previous animal studies and suggests that conventional TENS should be preferred in patients taking opioids on a regular basis. Perspective: This study shows that patients taking opioids on a regular basis are less susceptible to benefit from acupuncture-like TENS. This phenomenon is probably attributable to the fact that the analgesia induced by acupuncture-like TENS and opioids are mediated by the same receptors (i.e. μ opioid receptors)

Deciphering the role of endogenous opioids in high frequency TENS using low and high doses of naloxone

Abstract : Previous human studies have shown that the analgesic effect of high frequency TENS could not be reversed by low doses of naloxone. The aim of the present study was to reinvestigate the possible contribution of opioid receptors in high frequency TENS analgesia by using low (0.02 mg/kg) and high (0.14 mg/kg) doses of naloxone. Naloxone (high and low doses) and saline were administered intravenously to young healthy adults using a double-blind randomised cross-over design. For each visit, TENS (100 Hz, 60 sec) was applied for 25 minutes to the external surface of the left ankle. TENS intensity was adjusted to obtain strong but comfortable (innocuous) paresthesias. Experimental pain was evoked with a 1 cm2 thermode applied on the lateral aspect of the left heel. Subjective pain scores were obtained before, during and after TENS. Because preliminary analyses showed that the order of presentation affected the pattern of results, only the first visit of every participant could be analyzed without fear of contamination from possible carry-over effects. These revealed that TENS maintained its analgesic properties following the injection of saline (p<.001) and the injection of a low dose of naloxone (p<.05). However, when a high dose of naloxone was administered, TENS analgesia was completely blocked (p=.20). These results strongly suggest that high frequency TENS involves opioid receptors. An insufficient amount of opioid antagonist likely prevented previous human studies from discovering the importance of opioid receptors in producing high frequency/ low intensity TENS analgesia

Photometric visual servoing for omnidirectional cameras

International audience2D visual servoing consists in using data provided by a vision sensor for controlling the motions of a dynamic system. Most of visual servoing approaches has relied on the geometric features that have to be tracked and matched in the image acquired by the camera. Recent works have highlighted the interest of taking into account the photometric information of the entire image. This approach was tackled with images of perspective cameras. We propose, in this paper, to extend this technique to central cameras. This generalization allows to apply this kind of method to catadioptric cameras and wide field of view cameras. Several experiments have been successfully done with a fisheye camera in order to control a 6 degrees of freedom (dof) robot and with a catadioptric camera for a mobile robot navigation task

Les conflits hommes/animaux sauvages sous le regard de la géographie

Les conflits entre les hommes et la faune sauvage se révèlent par un ensemble de nuisances (destruction de cultures, attaques d’animaux d’élevage, compétitions pour les ressources naturelles, atteintes à la vie humaine) provoquées par différentes espèces animales. En réponse à ces nuisances ou pour tenter de les prévenir, les espèces responsables sont le plus souvent blessées ou tuées par les populations locales, même si d’autres solutions sont explorées avec l’aide des pouvoirs publics et des ONG (délocalisations, compensations, investissements dans la prévention). Dans plusieurs rapports publiés au cours des années 2000, la FAO a souligné une augmentation de ces conflits à l’échelle mondiale, faisant état de la diversité des cas de figure rencontrés d’une région du globe à l’autre. Actuellement, les sociétés confrontées à ces problèmes se posent de nombreuses questions sur leurs causes, leurs impacts sociaux et environnementaux mais aussi sur les solutions à mettre en œuvre pour obtenir une cohabitation plus pacifique. L’objectif de cet article est de montrer que ces interrogations peuvent être intégrées au champ de la géographie et de présenter les réponses que cette discipline peut apporter. Nous verrons alors que cette science a des atouts à faire valoir, que ce soit par ses méthodes d’analyse développées autour des conflits environnementaux, ses travaux sur la représentation des animaux ou son savoir-faire dans l’étude des facteurs spatiaux d’une grande variété de phénomènes.Conflicts between humans and wildlife refer to a range of nuisances (destruction of crops, livestock attacks, competition for natural resources, damage to human life) caused by different species. In response to these disturbances or in on order to prevent them, responsible species are often injured or killed by local populations, even if other solutions are explored with the help of government and NGOs (translocations, compensations, investments in prevention). In several reports published in the 2000s, the FAO noted an increase in conflicts around the world and the diversity of local situations. Human societies facing these issues work on causes, social and environmental impacts and solutions to reach a more peaceful coexistence. This paper shows how geography can be used to deal with human-wildlife conflicts through environmental conflict analysis, work on animal representation or study of spatial factors

Autofocusing-based visual servoing : application to MEMS micromanipulation.

International audienceIn MEMS microassembly areas, different methods of automatic focusing are presented in the literature. All these methods have a common point. Thus, the current autofocusing methods for microscopes need to perform a scanning on all the vertical axis of the microscope in order to find the peak corresponding to the focus (sharpen image). Those methods are time consuming. Therefore, this paper presents an original method of autofocusing based on a velocity control approach which is developed and validated on real experiments