Lacunarity of Fractal Superlattices: a Remote Estimation using Wavelets

The lacunarity provides a useful parameter for describing the distribution of gap sizes in discrete self-similar (fractal) superlattices and is used in addition to the similarity dimension to describe fractals. We show here that lacunarity, as well as the similarity dimension, can be remotely estimated from the wavelet analysis of superlattices impulse response. As a matter of fact, the skeleton—the set of wavelet-transform modulus-maxima—of the reflected signal overlaps two hierarchical structures in the time-scale domain: such that one allows the direct remote extraction of the similarity dimension, while the other may provide an accurate estimation of the lacunarity of the interrogated superlattice. Criteria for the choice of the mother wavelet are established for impulse response corrupted by additive Gaussian white noise

BCB Based Packaging for Low Actuation Voltage RF MEMS Devices

This paper outlines the issues related to RF MEMS packaging and low actuation voltage. An original approach is presented concerning the modeling of capacitive contacts using multiphysics simulation and advanced characterization. A similar approach is used concerning packaging development where multi-physics simulations are used to optimize the process. A devoted package architecture is proposed featuring very low loss at microwave range

Savoir et démocratie : le fondement normatif des univers sociologique et journalistique

International audienceThere are journalists who say they are sociologists, as there are sociologists who call themselves journalists, specifically improved journalists. They mention a common object and identity and a question of methods that would differ only in degree. In the opposite, some authors describe the specificity and the professional autonomy of these two activities in terms of object and methods. The two ways of thinking journalistic and sociological activities may be designated as continuism and discontinuism. For the continuist approach, these two activities are the same, the only difference lies in a different degree methods. For the discontinuist approach, this article defend, the two activities are based on two bearing and heterogeneous points as « knowledge» and « democracy ». If they are ideals in terms of what is actually observed concerning the practices of sociologists and journalists, this paper argues that these goals describe values and common knowledge. These professions have to be considered as distinct « universes » which recognize themselves shared rules.On trouve des journalistes qui se disent sociologues, comme on trouve des sociologues qui se disent journalistes, plus précisément des journalistes améliorés. Les uns et les autres avancent l'argument d'une identité et de l'objet visé par ces deux professions et des méthodes qui diffèrent seulement en degrés. De façon opposée, il se trouve des auteurs qui décrivent la spécificité et l'autonomie professionnelle des deux activités, en termes d'objet comme en termes de méthodes. On peut désigner de continuiste et de discontinuiste les deux manières de penser les activités journalistiques et sociologiques. La thèse continuiste décrit les deux activités par l'identité de leur objet et par des différences de degrés dans les méthodes. La thèse discontinuiste, que cet article défend, décrit les deux activités comme s'autorisant de deux points d'appui solides et radicalement hétérogènes : le « savoir » et la « démocratie ». Cet article défend la thèse que ces visées, si elles représentent des idéaux au regard des pratiques réellement observables des sociologues et des journalistes et des divers « idéaux-types » qui permettraient de les décrire, elles n'en recouvrent pas moins des valeurs et des savoir-faire communs qui font l'unité respective des deux professions qu'il faut concevoir comme des « univers » se reconnaissant des règles partagées

Miniaturisation d'antennes en bande VHF pour applications spatiales

Le développement de l électronique embarquée et miniaturisée est pleinement d actualité de nos jours, dans les domaines tels que l armement, la médecine, et les télécommunications. La miniaturisation des antennes large-bande, opérationnelles sur plus d une décade, présentent un défi particulier. Ces travaux de thèse proposent de travailler sur la miniaturisation d une antenne spirale, afin d en réduire l encombrement, à savoir son diamètre, tout en conservant au mieux ses caractéristiques de rayonnement et polarisation intrinsèques. Cette recherche sera appliquée à la bande des Très hautes Fréquence (Very High Frequencies VHF), allant de 30MHz à 300MHz La géométrie inédite proposée consiste à associer à une antenne spirale un ensemble d anneaux résonnants, dont le diamètre n excède pas celui de la spirale, et permettant de diminuer la fréquence basse de fonctionnement. Pour un ensemble de cinq anneaux associé à la spirale, la réduction de la fréquence basse de fonctionnement est de plus de 30%. Pour deux antennes spirales de même fréquence basse de fonctionnement, l antenne miniaturisée a donc un diamètre réduit de 30%, soit une surface réduite de 50%. Les performances de l état de l art d après lesquelles les réductions sur le diamètre des antennes spirales n excèdent pas 15% sont donc dépassées. De plus, d après cet état de l art, les méthodes de réduction appliquées aux antennes large bande dégradent en général le gain et l axial ratio dans les bandes basses de fréquences de fonctionnement. La méthode proposée permet de conserver l efficacité de l antenne, voire de l augmenter, dans les fréquences proches de la fréquence basse de fonctionnement. Le rayonnement de l antenne spirale miniaturisée dans la bande passante de l antenne sans anneaux n est pour autant pas modifiée. Ces résultats très encourageant ont été confirmés par la mesure d antennes spirales miniaturisées, réalisées pour un diamètre de 8cm et de 1m : une réduction de 30% du diamètre sans dégradation du rayonnement a été observée. Les mesures ont par ailleurs donné lieu à l étude de la réalisation d une antenne en bande VHF, avec pour implication les problématiques de réalisation (masse, encombrement, résistance mécanique) et de mesure (isolation, effets parasites en VHF avec une longueur d onde de 4m).Miniaturizing electronic devices is a great challenge in crucial research domain such as defense, medicine, and telecommunications. Wideband antenna miniaturization operating on more than a decade is a particular issue. This thesis presents an original method for miniaturizing a spiral antenna, reducing its diameter while keeping its bandwidth, its radiating performances and its axial ratio characteristics. This method is applied to UHF spiral antenna (from 750MHz) and VHF antenna (from 75MHz). The new geometry adds stacked resonant rings to an Archimedean spiral antenna. Their diameter are the same, hence no rise of the antenna diameter. For a 5-ring spiral antenna, the lowest operating frequency reduction is higher than 30%. That is equivalent to a 30% reduction of the diameter for two antennas sharing the same lowest operating frequency, hence a 50% reduction of the area of the antenna. These reduction factors surpass the reduction factors of the state of art of 15%. Besides, according to the state of art, the miniaturizing techniques imply some degradation of the gain and axial ratio performances at the lowest operating frequencies. The new method improves on the other hand these characteristics at these frequencies. At higher frequencies, the rings do not interfere with the matching of neither the spiral antenna nor its radiation characteristics. These results were validated by fabricated antenna measurements. A 30% reduction of the diameter was obtained on a 5-ring-8cm-large antenna as well as on a 5-ring-1m-large antenna. No impairment was noticed on the radiation of the antennas, even at the lowest operating frequencies. The thesis also discusses the difficulties which came in addition for the fabrication (mass, size and mechanical resistance) and measurement (radiation interferences and measurement isolation the wavelength being 4m) of the VHF antenna.TOULOUSE-INP (315552154) / SudocSudocFranceF

Peptides to Overcome the Limitations of Current Anticancer and Antimicrobial Nanotherapies

Biomedical research devotes a huge effort to the development of efficient non-viral nanovectors (NV) to improve the effectiveness of standard therapies. NVs should be stable, sustainable and biocompatible and enable controlled and targeted delivery of drugs. With the aim to foster the advancements of such devices, this review reports some recent results applicable to treat two types of pathologies, cancer and microbial infections, aiming to provide guidance in the overall design of personalized nanomedicines and highlight the key role played by peptides in this field. Additionally, future challenges and potential perspectives are illustrated, in the hope of accelerating the translational advances of nanomedicine

Translational Genomics in Legumes Allowed Placing In Silico 5460 Unigenes on the Pea Functional Map and Identified Candidate Genes in Pisum sativum L.

To identify genes involved in phenotypic traits, translational genomics from highly characterized model plants to poorly characterized crop plants provides a valuable source of markers to saturate a zone of interest as well as functionally characterized candidate genes. In this paper, an integrated view of the pea genetic map was developed. A series of gene markers were mapped and their best reciprocal homologs were identified on M. truncatula, L. japonicus, soybean, and poplar pseudomolecules. Based on the syntenic relationships uncovered between pea and M. truncatula, 5460 pea Unigenes were tentatively placed on the consensus map. A new bioinformatics tool, http://www.thelegumeportal.net/pea_mtr_translational_toolkit, was developed that allows, for any gene sequence, to search its putative position on the pea consensus map and hence to search for candidate genes among neighboring Unigenes. As an example, a promising candidate gene for the hypernodulation mutation nod3 in pea was proposed based on the map position of the likely homolog of Pub1, a M. truncatula gene involved in nodulation regulation. A broader view of pea genome evolution was obtained by revealing syntenic relationships between pea and sequenced genomes. Blocks of synteny were identified which gave new insights into the evolution of chromosome structure in Papillionoids and Eudicots. The power of the translational genomics approach was underlined

On unitarizability in the case of classical p-adic groups

In the introduction of this paper we discuss a possible approach to the unitarizability problem for classical p-adic groups. In this paper we give some very limited support that such approach is not without chance. In a forthcoming paper we shall give additional evidence in generalized cuspidal rank (up to) three.Comment: This paper is a merged and revised version of ealier preprints arXiv:1701.07658 and arXiv:1701.07662. The paper is going to appear in the Proceedings of the Simons Symposium on Geometric Aspects of the Trace Formul

Transdimensional inference of archeomagnetic intensity change

One of the main goals of archeomagnetism is to document the secular changes of Earth's magnetic field by laboratory analysis of the magnetization carried by archeological artefacts. Typical techniques for creating a time-dependent model assume a prescribed temporal discretisation which, when coupled with sparse data coverage, require strong regularisation generally applied over the entire time series in order to ensure smoothness. Such techniques make it difficult to characterise uncertainty and frequency content, and robustly detect rapid changes. Key to proper modelling (and physical understanding) is a method that places a minimum level of regularisation on any fit to the data. Here we apply a transdimensional Bayesian technique based on piecewise linear interpolation to sparse archeointensity datasets, in which the temporal complexity of the model is not set a priori, but is self-selected by the data. The method produces two key outputs: (i) a posterior distribution of intensity as a function of time, a useful tool for archeomagnetic dating, whose statistics are smooth but formally unregularised; (ii) by including the data ages in the model of unknown parameters, the method also produces posterior age statistics of each individual contributing datum. We test the technique using synthetic datasets and confirm agreement of our method with an integrated likelihood approach. We then apply the method to three archeomagnetic datasets all reduced to a single location: one temporally well-sampled within 700km from Paris (here referred to as Paris700), one that is temporally sparse centred on Hawaii, and a third (from Lübeck, Germany and Paris700) that has additional ordering constraints on age from stratification. Compared with other methods, our average posterior distributions largely agree, however our credible intervals appear to much better reflect the uncertainty during periods of sparse data coverage. Because each ensemble member of the posterior distribution is piecewise linear, we only fit oscillations when required by the data. As an example, we show that an oscillatory signal, associated with temporally-localised intensity maxima reported for a sparse Hawaiian dataset, is not required by the data. However, we do recover the previously reported oscillation of period 260 yrs for the Paris700 dataset and compute the probability distribution of the period of oscillation. We further demonstrate that such an oscillation is unresolved when accounting for age uncertainty by using a fixed age and with an artificially inflated error budget on intensity

Temporal Dynamics of European Bat Lyssavirus Type 1 and Survival of Myotis myotis Bats in Natural Colonies

Many emerging RNA viruses of public health concern have recently been detected in bats. However, the dynamics of these viruses in natural bat colonies is presently unknown. Consequently, prediction of the spread of these viruses and the establishment of appropriate control measures are hindered by a lack of information. To this aim, we collected epidemiological, virological and ecological data during a twelve-year longitudinal study in two colonies of insectivorous bats (Myotis myotis) located in Spain and infected by the most common bat lyssavirus found in Europe, the European bat lyssavirus subtype 1 (EBLV-1). This active survey demonstrates that cyclic lyssavirus infections occurred with periodic oscillations in the number of susceptible, immune and infected bats. Persistence of immunity for more than one year was detected in some individuals. These data were further used to feed models to analyze the temporal dynamics of EBLV-1 and the survival rate of bats. According to these models, the infection is characterized by a predicted low basic reproductive rate (R0 = 1.706) and a short infectious period (D = 5.1 days). In contrast to observations in most non-flying animals infected with rabies, the survival model shows no variation in mortality after EBLV-1 infection of M. myotis. These findings have considerable public health implications in terms of management of colonies where lyssavirus-positive bats have been recorded and confirm the potential risk of rabies transmission to humans. A greater understanding of the dynamics of lyssavirus in bat colonies also provides a model to study how bats contribute to the maintenance and transmission of other viruses of public health concern