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(1) Background: Is variation among the communities of a metacommunity higher than within the communities? Community ecologists and population geneticists often characterize the structure of metacommunities by partitioning variation (diversity) into the two following components using measures such as FST or GST and α- and β-diversity. The within-communities component is usually some average of (type, species, genetic) diversities within the communities, and the among-communities component is the additive or multiplicative complement of the overall diversity. Such an among-communities component lacks independent conceptual specification, a matter of long-standing dispute. Only if the two components are independently and commensurably specified can the central question of comparability be answered meaningfully. (2) Methods: A novel approach to overcoming this conceptual weakness identifies two principles of the partitioning of variation among communities (concentration and division) then relates these principles to the common notions of variation (diversity) within and among communities, distinguishes primary indicators to quantify the partitioning principles, transforms the indicators into conceptually independent measures (indices) of variation within and among communities, and by this attains their commensurability and thus comparability. The application of the methods to quantifying the effects of evolutionary mechanisms is outlined. (3) Results: Common approaches are corrected and extended. (a) Analyses of metacommunity/metapopulation structures that rely on apportionment or related indices and take its complement to be differentiation yield incomparable measures of variation within and among communities. (b) The common practice of partitioning the total diversity into additive or multiplicative components produces the inconsistent ranking of the two components. (c) Community concentration and division can result from elementary processes of adaptive differentiation and migration (gene flow) among communities, where the (commensurable) amounts of community concentration and division reflect the relative participation of these processes in metacommunity structuring and translate directly into the measures of diversity within and among communities. (d) The modelling of the contributions of the two partitioning principles to the metacommunity structure is restricted by the marginal distributions of types and community affiliation. (e) The model demonstrates the degree to which adaptational processes at the metacommunity level are mixtures of adaptational events within and among communities.

In a general sense, a metacommunity can be considered as a network of communities, the coherence of which is based on characteristics that are shared by members of different communities, whatever forces were responsible (dispersal, migration, local adaptation, etc.). The purpose is to show that by basing the assessment of coherence on the degree of nestedness of one community within another with respect to the shared characteristics, coherence components can be identified within the network. To assess coherence, a measure of nestedness is developed, and its application to complex (variable) object differences (including multiple traits or characters) is investigated. A community network is then viewed as a graph in which the nodes represent the communities and the edges connecting nodes are weighted by the reverse of the degrees of nestedness between the corresponding communities. Given this framework, it is argued that a minimum requirement for a set of communities to be coherent is the existence of a spanning tree known from graph theory, i.e. a subgraph that connects all nodes through a cycle-free sequence of edges with positive weights. Of all spanning trees, minimum spanning trees (MST, or spanning trees with the minimum sum of edge weights) are most indicative of coherence. By expressing the degree of coherence as one minus the average weight of the edges of an MST, it is uniquely determined which communities form a coherent set at any given level of community distinctness. By this method, community networks can be broken down into coherence components that are separated at a specified distinctness level. This is illustrated in a worked example showing how to apply graph theoretical methods to distinguish coherence components at various threshold levels of object difference (resolution) and community distinctness. These results provide a basis for discussion of coherence gradients and coherence at various levels of distinctness in terms of MST-characteristics. As intuitively expected and analytically confirmed, coherence is a non-decreasing function of the object difference threshold, and the number of coherence components is a non-increasing function of both the object difference and the community distinctness thresholds.

International audience; In this paper, experimental results of broadband noise reduction in an acoustic flow duct are presented. An active liner composed of an array of electroacoustic absorbers is used. The control law is based on the pressure-based, current driven digital architecture for impedance control with a local control strategy. A wind tunnel test rig named Caïman has been used for the experimental validation. The results confirm the adaptability and the stability of the whole system with the local control strategy. The air flow slightly reduces the efficiency while maintaining the adaptability and the stability.

During the past decade, the use of DNA for forensic applications has been extensively implemented for plant and animal species, as well as in humans. Tracing back the geographical origin of an individual usually requires genetic assignment analysis. These approaches are based on reference samples that are grouped into populations or other aggregates and intend to identify the most likely group of origin. Often this grouping does not have a biological but rather a historical or political justification, such as "country of origin". In this paper, we present a new nearest neighbour approach to individual assignment or classification within a given but potentially imperfect grouping of reference samples. This method, which is based on the genetic distance between individuals, functions better in many cases than commonly used methods. We demonstrate the operation of our assignment method using two data sets. One set is simulated for a large number of trees distributed in a 120km by 120km landscape with individual genotypes at 150 SNPs, and the other set comprises experimental data of 1221 individuals of the African tropical tree species Entandrophragma cylindricum (Sapelli) genotyped at 61 SNPs. Judging by the level of correct self-assignment, our approach outperformed the commonly used frequency and Bayesian approaches by 15% for the simulated data set and by 5-7% for the Sapelli data set. Our new approach is less sensitive to overlapping sources of genetic differentiation, such as genetic differences among closely-related species, phylogeographic lineages and isolation by distance, and thus operates better even for suboptimal grouping of individuals.

Electron beam lithography was used to fabricate platinum μ-contacts over tungsten oxide nanorods formed on a mica substrate. This made possible the measurement of sensorial response of these self-assembled tungsten oxide nanorods to hydrogen gas for the first time. The nanorods were prepared by thermal evaporation from an oxide source. Consequently, two types of conductometric sensors were assembled: a) percolating network of nanorods and b) set of individually contacted WO3 nanorods. The preparation procedures are described in detail and the comparison of response of both types of assemblies is given. The first sensorial measurements revealed a good response of the b) type of sensor and the minimum repeatedly detected concentration of H2 was 50 ppm.

Summary Background Acute Heart Failure (AHF) is a main cause of acute respiratory failure for patients admitted to Emergency Departments (ED). Non-invasive ventilation (NIV) is recommended as a first-line therapy for acute respiratory failure in patients with AHF, but its role in the ED for very old patients is poorly defined. The primary goal of this study was to estimate NIV prescription for older patients with AHF. Secondary goals were to identify determinants of NIV prescription, and to measure the association between NIV and day-8 outcomes in elderly patients. Methods Retrospective observational study at the ED of the University Hospital of Poitiers, France, assessing patients over 75 years old with AHF who had indication for NIV. Results A total of 213 patients were included and NIV was only performed as BiPAP and in 17.4%. Patients who received NIV were younger (median [interquartile range], 85 [81–90] versus 87 [84–92] years; P = 0.045) and had lower pH values (7.29 [7.21–7.37] versus 7.41 [7.34–7.45]; P Conclusions In our ED, NIV for AHF is uncommonly performed in the elderly and seems not associated with better outcome in this population regardless of comorbidities and autonomy.

In the frame of a study on aeronautic composite structures submitted to laser irradiation, we have assessed the thermo mechanical behavior of carbon epoxy composite. The carbon fibers withstand ∼1 kW/cm 2 power density but the matrix is completely burned. At higher power densities, an ablation of the fibers is observed. The behavior of the matrix composition which included epoxy based resin and a lot of additives, plasticizer, delaying agents, and surfactants …, has also featured some internal ebullition phenomena. Such ebullition has been attributed to the additives thanks to a comparative experimental study on pure epoxy resin and matrix behavior. The resin is optically semi-transparent at the laser wavelength and shows an ablative behavior. The matrix is an optically diffused media due to the inclusions of micro bubbles of additives within the resin. These inclusions which have lower degradation temperature compared to the epoxy resin one induced an internal ebullition inside the epoxy based matrix. These internal ebullition phenomena create local overpressures speeding up the delaminating phenomena of the composite. We have studied the thermo-mechanical behavior of our samples. We have demonstrated a simple linear dependence of the mechanical degradation of carbon epoxy composite material and the laser deposed energy.

Orbital ordering below 30 K was previously observed in the ferromagnetic ${\text{YTiO}}_{3}$ compound both by polarized neutron diffraction (PND) and x-ray magnetic diffraction (XMD). In this paper we report a procedure for the joint refinement of a unique spin-density model based on both PND and XMD data. The distribution of the unpaired $3d$ electron of titanium is clearly seen on the magnetization density reconstructed by the maximum entropy method from the PND data collection at 5 K. The ${\text{Ti}}^{3+}$ $3d$ orbital populations obtained by joint model refinement are discussed in terms of the orbital ordering scheme. Small but significant magnetic moments on apical oxygen ${\text{O}}_{1}$ and yttrium atoms are found. The agreement between experimental and theoretical spin densities obtained using density functional theory is discussed.

Selection and migration are the major deterministic forces that control adaptational processes of differentiation among communities. With the aim of distinguishing between their effects on metacommunity structure, compositional differentiation in metacommunities is viewed from dual perspectives: between communities for their distributions of the types (CDT, the common perspective) and between types for the distribution of their community membership (TDC). A measure of dispersion and four measures that fulfill the basic characteristics of differentiation (maximality for complete difference and minimality in the absence of differences) from both perspectives are introduced and compared. Conceptual modeling of selection and migration (the latter distinguished for its control by descent and type) yields relationships between the values of the measures that, when not fulfilled, lead to rejection of the model. Major results are: measures of dispersion that are not measures of differentiation cannot distinguish between the two perspectives; the commonly held view that type-independent migration homogenizes communities with respect to type distributions is invalid, though it does homogenize types for their community membership; after type-independent migration, differentiation among communities with respect to the source communities of their members bounds differentiation for any other trait; the effects of migration on CDT and TDC cannot always be realized by selection, and vice versa; effective proportions of migration can be obtained from measures of compositional differentiation and number of communities. The last result is based on the general concept of effective variables applied to conceptual models.

The morphology, the structure and the orientation of tungsten oxide nanorods grown on mica are investigated as a function of the deposition time. The previous results are recalled to point out the changes with the nanorod thickness. The investigations were conducted by Atomic Force Microscopy (AFM) and Reflection High Energy Electron Diffraction (RHEED). The results evidence two successive growth modes. In the first stage thin and long nanorods were formed. They grew layer by layer with a hexagonal tungsten bronze structure and two different (1−10) and (2–10) planes parallel to the mica surface. In the second stage, as the deposition time increased thin nanorods with the (1−10) orientation grew in thickness when the others preserve their morphology and structure. In the discussion the difference between the two growth modes is emphasized. In the first stage the nanorod growth proceeds mainly by the surface diffusion of K x WO 3 species. In the second stage the growth is due to the by direct impinging of WO 3 molecules on some thin nanorods having already the (1−10) orientation, leading to growth of thick nanorods with a monoclinic structure.

La amputacion del miembro superior, debido a que su principal causa es traumatica, solo supone una proporcion muy baja de todas las amputaciones. Las protesis mioelectricas o mioelectronicas son las mas utilizadas y se describen brevemente. La rehabilitacion (que se realiza durante dos meses en los casos mas sencillos) es totalmente distinta a la de la amputacion del miembro inferior : en el primer caso, el paciente es joven y ha sufrido un traumatismo, mientras que en el otro es un anciano y pluripatologico. Tambien requiere mucho tiempo de rehabilitacion durante el dia (8-10 horas diarias). El tratamiento, que se basa en diversas evaluaciones, sobre todo mioelectricas y de calidad muscular, consta de tres partes: la rehabilitacion preprotesica (donde el aspecto psicologico, la rehabilitacion ortopedica y el trabajo con vistas a la adaptacion de la protesis son los tres objetivos esenciales), la rehabilitacion con la protesis (que se realiza en tres fases y se basa en la adquisicion de una base tecnica solida, sin omitir el desarrollo de la «sensibilidad» y de la «velocidad» con la protesis) y la readaptacion (donde el paciente debe poner en practica sus logros en su vida diaria y laboral, la conduccion de vehiculos y la practica deportiva). Las dos ultimas partes se basan en la pedagogia por objetivos, que permite perfeccionar la rehabilitacion y la readaptacion realizando un seguimiento preciso del paciente y una cumplimentacion perfecta de su historia clinica. Esta protesis del miembro superior, considerada como una «pinza sofisticada portatil» y no como la mano que nunca sera, junto a un equipo reducido y coordinado, compuesto por el medico, el protesista y los rehabilitadores (que deben mostrarse disponibles, entusiastas y exigentes), permiten establecer un contrato moral muy positivo con el paciente.

During the past decade, the use of DNA for forensic applications has been extensively implemented for plant and animal species, as well as in humans. Tracing back the geographical origin of an individual usually requires genetic assignment analysis. These approaches are based on reference samples that are grouped into populations or other aggregates and intend to identify the most likely group of origin. Often this grouping does not have a biological but rather a historical or political justification, such as “country of origin”.In this paper, we present a new nearest neighbour approach to individual assignment or classification within a given but potentially imperfect grouping of reference samples. This method, which is based on the genic distance between individuals, functions better in many cases than commonly used methods. We demonstrate the operation of our assignment method using two data sets. One set is simulated for a large number of trees distributed in a 120 km by 120 km landscape with individual genotypes at 150 SNPs, and the other set comprises experimental data of 1221 individuals of the African tropical tree speciesEntandrophragma cylindricum(Sapelli) genotyped at 61 SNPs. Judging by the level of correct self-assignment, our approach outperformed the commonly used frequency and Bayesian approaches by 15% for the simulated data set and by 5 to 7% for the Sapelli data set.Our new approach is less sensitive to overlapping sources of genetic differentiation, such as genic differences among closely-related species, phylogeographic lineages and isolation by distance, and thus operates better even for suboptimal grouping of individuals.