A Multiband Biconical Log-periodic Antenna for Swarm Communications

In this paper, we present a specific multiband antenna design that addresses the problem of communication with unmanned aerial vehicles (UAVs). We consider a scenario where multiband single-antenna UAV communicates with the rest of the swarm members that are equipped with similar antennas. The key point in the design is that the communication does not require high or low elevation angles in most of the cases. The suggested design has a sufficient degree of freedom to select the desired features for the field pattern while keeping other features such as antenna impedance and gain relatively stable or at least in the acceptable operation region

Thyroxine differentially modulates the peripheral clock: lessons from the human hair follicle

The human hair follicle (HF) exhibits peripheral clock activity, with knock-down of clock genes (BMAL1 and PER1) prolonging active hair growth (anagen) and increasing pigmentation. Similarly, thyroid hormones prolong anagen and stimulate pigmentation in cultured human HFs. In addition they are recognized as key regulators of the central clock that controls circadian rhythmicity. Therefore, we asked whether thyroxine (T4) also influences peripheral clock activity in the human HF. Over 24 hours we found a significant reduction in protein levels of BMAL1 and PER1, with their transcript levels also decreasing significantly. Furthermore, while all clock genes maintained their rhythmicity in both the control and T4 treated HFs, there was a significant reduction in the amplitude of BMAL1 and PER1 in T4 (100 nM) treated HFs. Accompanying this, cell-cycle progression marker Cyclin D1 was also assessed appearing to show an induced circadian rhythmicity by T4 however, this was not significant. Contrary to short term cultures, after 6 days, transcript and/or protein levels of all core clock genes (BMAL1, PER1, clock, CRY1, CRY2) were up-regulated in T4 treated HFs. BMAL1 and PER1 mRNA was also up-regulated in the HF bulge, the location of HF epithelial stem cells. Together this provides the first direct evidence that T4 modulates the expression of the peripheral molecular clock. Thus, patients with thyroid dysfunction may also show a disordered peripheral clock, which raises the possibility that short term, pulsatile treatment with T4 might permit one to modulate circadian activity in peripheral tissues as a target to treat clock-related disease

Pour une patrimonialisation intégrée au développement urbain : élaboration des conditions de conciliations entre obligations de préservation et impératifs de développement à travers l’étude de cas d’Avignon

The preservation of historic cities requires on behalf of the actors committed to the urban development of the urban historic ensemble (EUH) additional efforts to extend their actions beyond isolated buildings. In practice, when developing historic urban ensembles, the conservation of the urban heritage seems to be relegated to an external if compulsory constraint which has to be overcome. This situation often results in the opposition of two aims: development versus conservatory.The question of how can the conservation of urban heritage be better considered is debated on international, national and local scales. By joining this current debate, our thesis aims to answer the following question: how can we improve the management of the imperatives behind urban development in historic cities, when tied to patrimonial obligation towards urban ensembles?The literature review helped us show that the notion of urban heritage, which justifies the urban preservation, was born in the minds of planners confronted with urban development, linking the notion of the urban heritage more closely to that of development than to conservation. In the absence of one that would move towards urban heritage preservation and confronted with the dominant if opposite postures, we realized, based on the literature review, that the opposition shared anchoring elements: the preservation paradigm of actions, centered on buildings and unsuitable in the case of ensembles, this paradigm supported by divergent institutional cultures and strengthened by an opposition between the modes of local implication.Considering the well-known difficulties and the contributions of the literature review, which clarifies the nature of the opposition between heritage conservation and development, how can the preservation of historic urban ensembles be thought differently? To answer that question, we propose reflecting on urban preservation as integrated to urban development.On the methodological level, the nature of the opposition between development and conservation sends us back to the analysis of what takes place on the field. We chose to look at the historic center of Avignon, where various actors have attempted to exceed this opposition. Avignon, as a mid-sized city of the South of France, is endowed with one of France’s biggest protected areas which cover the entire historic center. The history of the actions carried out in the intramural brings out archetypical situations which illustrate the opposition between development and conservation. The case study allowsus to intellectualise the mobilization of urban heritage on 3 levels: Institutional, Find and Urban action. Each of these levels distinguishes itself by the nature of the mobilization and by the point at which are made manifest the mobilization of the material and symbolic dimensions of urban heritage. Starting with the case study, we have conceptualised a model which goes beyond a restricted reading focused on the opposition to think out urban development within the context of urban conservation. The model brings into the urban development the notion of urban heritage designation as a succession of actions which qualify urban historic ensemble as heritage and preserve them. On the scientific level, the model mobilizes notions, borrowed from sociological, communicational, ethnological and geographical approaches of heritage designation. It proposes a new analytical framework for thinking about the actors involved in the urbanistic management of the historic urban ensembles, so as to exceed the oppositions and guarantee a sustainable creation of urban heritage which does not constitute an obstacle for the imperatives of development. The model helps us see the roles at stake and organizes the various actions undertaken by the various actors in favour of both heritage and development to come up with an integrated urban heritage designationLa thèse porte sur la patrimonialisation de l’urbain à partir des dispositifs censés encadrer le devenir du patrimoine dans les villes et qui se confronte aux logiques de développement urbain. La posture situe la patrimonialisation de l'urbain dans un processus historique. Initialement centrée sur les monuments, identifiés pour leurs valeurs, la patrimonialisation a englobé les contextes pour ensuite considérer les ensembles comme des patrimoines. La patrimonialisation des ensembles urbains doit prendre en compte les multiples dimensions et acteurs impliqués dans la gestion des villes. Ces évolutions nécessitent la conciliation entre la préservation du patrimoine et le développement urbain. Comment, dès lors, penser concrètement une patrimonialisation, spécifique à l’urbain ?L’étude se fonde sur une reconstruction des programmes de projets dans l’intramuros d’Avignon (France) à partir du croisement de données recueillies dans les documents consignés dans les archives municipales (couvrant la période de 1957-2004) avec des données issues d’entretiens avec des acteurs impliqués (entretiens semi-directifs avec 14 personnes ressources). Ainsi, les sources (orales) de première main permettent d’éclaircir et de compléter les sources écrites (archives). En observant les expérimentations entreprises à Avignon, depuis la Loi Malraux en 1964, nous mesurons la construction sociohistorique des pratiques locales qui se sont structurées autour de la préservation du patrimoine en rapport aux orientations nationales et les difficultés d’une prise en compte de la ville historique dans l'évolution urbaine de la ville d’Avignon.La recherche se concentre sur trois (3) moments : les années 1960, 1970 et 1980. Le premier illustre une prise de conscience de l’urgence de préserver les quartiers historiques par la mise en place des secteurs sauvegardés. Ce dernier reste imprégné par la conservation des monuments comme des objets isolés sans arriver à prendre en charge les ensembles. Le deuxième ancre la préservation des ensembles dans les efforts de développement urbain à travers la mise en place des Contrats Ville-Moyenne sous la supervision de l’État. Enfin, le troisième s’affranchit du contrôle de l’État en instaurant des Zones d’Aménagements différées adossées sur des projets issus d’études insistant sur la dimension patrimoniale. L’analyse de ces trois moments consiste à repérer les orientations prises en faveur, ou non, du patrimoine et à rendre compte des contextes et des acteurs impliqués dans ces prises de décisions. En nous référant à des travaux en sciences humaines (sociologie, géographie, anthropologie) et concernant spécifiquement le patrimoine (Amougou, Davallon, Gravari-Barbas, Rautenberg, Veschambres…), nous avons démontré que les orientations qui compromettent la préservation du patrimoine viennent de l’absence de lien entre trois (3) niveaux, repérés lors de l’analyse : la trouvaille du patrimoine, la mise en politique du patrimoine et l’action urbaine. Pour dépasser ces manques de liens entre les trois, la thèse propose un outil pour penser la patrimonialisation de l’urbain, qui réunit et met en relation les conditions de réussite de la patrimonialisation d’un ensemble urbain historique.La recherche doctorale a ainsi permis de produire des connaissances à visée opérationnelle, en plus d’ouvrir plusieurs pistes qu’il serait pertinent d’approfondir. Sur le plan méthodologique, le repérage des mesures prises en faveur ou contre le patrimoine nécessiterait, compte tenu de la complexité du problème tel que posé, une analyse transversale plus approfondie pour définir des indices en faveur de la préservation ou bien de la détérioration. Dans ce sens, les résultats dégagés à partir du cas d’Avignon gagneraient à être confrontés à d’autres terrains. Par ailleurs, l’arrimage de ce travail aux derniers développements en matière de conservation urbaine portés à l'échelle internationale, par ICOMOS et par l’UNESCO, paraît porteu

Male pattern hair loss: can developmental origins explain the pattern?

Male pattern hair loss (MPHL), also referred to as male androgenetic alopecia (AGA) is the most common type of non-scarring progressive hair loss, with 80% of men suffering from this condition in their lifetime. In MPHL, the hair line recedes to a specific part of the scalp which cannot be accurately predicted. Hair is lost from the front, vertex, and the crown, yet temporal and occipital follicles remain. The visual effect of hair loss is due to hair follicle miniaturisation, where terminal hair follicles become dimensionally smaller. Miniaturisation is also characterised by a shortening of the growth phase of the hair cycle (anagen), and a prolongation of the dormant phase (kenogen). Together, these changes result in the production of thinner and shorter hair fibres, referred to as miniaturised or vellus hairs. It remains unclear why miniaturisation occurs in this specific pattern, with frontal follicles susceptible while occipital follicles remain in a terminal state. One main factor we believe to be at play, which will be discussed in this viewpoint, is the developmental origin of the skin and hair follicle dermis on different regions of the scalp

La ténorraphie percutanée dans les ruptures fraîches du tendon calcanéen : à propos de 67 cas

La rupture du tendon calcanéen est une des lésions les plus fréquentes en pathologie du sport, les deux options thérapeutiques classiques sont le traitement orthopédique et la chirurgie à ciel ouvert. Dans le but de minimiser ces complications, des techniques mini-invasives de ténorraphie percutanée ont été proposées dont les résultats sont encourageants. Il s'agit d'une étude rétrospective d'une série de cas de rupture sous cutanée du tendon d'Achille s'étalant de Avril 2005 au Juin 2012 concernant 67 patients ; 11 femmes et 56 hommes avec un âge moyen de 41 ans. La cause principale était un accident de sport dans 45 cas. Le  diagnostic était évident à l'examen chez tous les patients. Dans deux cas il s'agissait d'une rerupture survenant à 1 et 5 ans d'un traitement orthopédique. Dans un  cas il s'agissait d'une rerupture survenant après une ténorraphie percutanée. Dans deux cas il s'agissait d'une rupture sur tendinopathie chronique. Tous les  patients avaient bénéficié d'une radio de la cheville qui avait montré une  horizontalisation du calcanéum chez 5 patients et surtout elle n'avait pas montré de fracture associée, alors que 15 patients avaient bénéficié d'une échographie qui a confirmé le diagnostic. Tous les patients avaient été opérés dans un délai de moins de 48 heures Une ténorraphie percutanée a été pratiqué chez tous les patients. Le recul moyen est de 43 mois, trois patients ont été perdus de vue Nous  avons noté une reprise des activités professionnelle effective en moyen 90 jours après l'intervention et celle des activités sportive à 6 mois en moyenne L'état  cutané local a été jugée bon dans 63 cas. Par ailleurs les complications ont été marquées par un seul cas d'infection ayant nécessité une reprise chirurgical a été noté mise à plat, trois cas de rerupture repris par suture à ciel ouvert, un cas d'algodystrophie et un cas de tendinopathie Il n'y a eu aucune complication  thromboembolique ni neurologique. Il n'existe pas de réel consensus concernant la prise en charge des ruptures du tendon calcanéen. Ainsi, La ténorraphie  percutanée du tendon calcanéen est une méthode simple rapide et efficace, elle allie les avantages de la chirurgie à ciel ouvert en termes de pourcentage de rerupture et les avantages du traitement fonctionnel en rapport avec un faible risque infectieux.Key words: Ténorraphie percutanée, rupture fraîche, tendon calcanéen, spor

GLDPC-Staircase AL-FEC codes: A Fundamental study and New results

International audienceThis paper provides fundamentals in the design and analysis of Generalized Low Density Parity Check (GLDPC)-Staircase codes over the erasure channel. These codes are constructed by extending an LDPC-Staircase code (base code) using Reed Solomon (RS) codes (outer codes) in order to benefit from more powerful decoders. The GLDPC-Staircase coding scheme adds, in addition to the LDPC-Staircase repair symbols, extra-repair symbols that can be produced on demand and in large quantities, which provides small rate capabilities. Therefore, these codes are extremely flexible as they can be tuned to behave either like predefined rate LDPC-Staircase codes at one extreme, or like a single RS code at another extreme, or like small rate codes. Concerning the code design, we show that RS codes with " quasi " Hankel matrix-based construction fulfill the desired structure properties, and that a hybrid (IT/RS/ML) decoding is feasible that achieves Maximum Likelihood (ML) correction capabilities at a lower complexity. Concerning performance analysis, we detail an asymptotic analysis method based on Density evolution (DE), EXtrinsic Information Transfer (EXIT) and the area theorem. Based on several asymptotic and finite length results, after selecting the optimal internal parameters, we demonstrate that GLDPC-Staircase codes feature excellent erasure recovery capabilities, close to that of ideal codes, both with large and very small objects. From this point of view they outperform LDPC-Staircase and Raptor codes, and achieve correction capabilities close to those of RaptorQ codes. Therefore all these results make GLDPC-Staircase codes a universal Application-Layer FEC (AL-FEC) solution for many situations that require erasure protection such as media streaming or file multicast transmission

A Software Architecture Framework for Home Service Robots

Over the last years, home service robots have a wide range of potential applications, such as home security, patient caring, cleaning, etc. When developing robot software, one of the main challenges is to build the software architectural model. Software architecture is used throughout the software life-cycle for supporting analysis, guiding development, and acting as a roadmap for designers and implementers. Though many software architectures for robotic systems have been defined, none of them have reached all its objectives due to the great variability among systems behaviors, and still lack systematic techniques to derive the robot software architecture from its requirements model. In this paper, we present a generic architectural model for home service robots allowing for software architecture design, and preserving a continuous architectural view all along the development cycle. While avoiding the predominant decomposition problems, our approach allows for integration of the architectural components in a systematic and comprehensive way for efficient maintainability and reusability

Simulation of Metal Forming Processes with a 3D Adaptive Remeshing Procedure

In this paper, a fully adaptive 3D numerical methodology based on a tetrahedral element was proposed in order to rove the finite element simulation of any metal forming process. This automatic methodology was implemented in a computational platform which integrates a finite element solver, 3D mesh generation and a field transfer algorithm. The proposed remeshing method was developed in order to solve problems associated with the severe distortion of elements subject to large deformations, to concentrate the elements where the error is large and to coarsen the mesh where the error is small. This leads to a significant reduction in the computation times while maintaining simulation accuracy . In addition, in order to enhance the contact conditions, this method has been coupled with a specific operator to maintain the initial contact between the workpiece nodes and the rigid tool after each remeshing step. In this paper special attention is paid to the data transfer methods and the necessary adaptive remeshing steps are given. Finally, a numerical example is detailed to demonstrate the efficiency of the approach and to compare the results for the different field transfer strategie