Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
RATIONALE: Optimal management of complicated parapneumonic effusions (CPPE) remains controversial. OBJECTIVES: to assess safety and efficacy of iterative therapeutic thoracentesis (ITTC), the first-line treatment of CPPE in Rennes University Hospital. METHODS: Patients with CPPE were identified through our computerized database. We retrospectively studied all cases of CPPE initially managed with ITTC in our institution between 2001 and 2010. ITTC failure was defined by the need for additional treatment (i.e. surgery or percutaneous drainage), or death. RESULTS: Seventy-nine consecutive patients were included. The success rate was 81% (n = 64). Only 3 patients (4%) were referred to thoracic surgery. The one-year survival rate was 88%. On multivariate analysis, microorganisms observed in pleural fluid after Gram staining and first thoracentesis volume ≥450 mL were associated with ITTC failure with adjusted odds-ratios of 7.65 [95% CI, 1.44-40.67] and 6.97 [95% CI, 1.86-26.07], respectively. The main complications of ITTC were iatrogenic pneumothorax (n = 5, 6%) and vasovagal reactions (n = 3, 4%). None of the pneumothoraces required chest tube drainage, and no hemothorax or re-expansion pulmonary edema was observed. CONCLUSIONS: Although not indicated in international recommendations, ITTC is safe and effective as first-line treatment of CPPE, with limited invasiveness.
ISSN: 1932-6203

hal-00945622
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00945622
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00945622/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00945622/file/fetchObject.pdf
PUBMED : 24400113

Éditeur(s) : HAL CCSD
Résumé : 28 pages, 6 figures
We study a universal object for the genealogy of a sample in populations with mutations: the critical birth-death process with Poissonian mutations, conditioned on its population size at a fixed time horizon. We show how this process arises as the law of the genealogy of a sample in a large class of critical branching populations with mutations at birth, namely populations converging, in a large population asymptotic, towards the continuum random tree. We extend this model to populations with random foundation times, with (potentially improper) prior distributions g_i: xmapsto x^{-i}, iinZ_+, including the so-called uniform (i=0) and log-uniform (i=1) priors. We first investigate the mutational patterns arising from these models, by studying the site frequency spectrum of a sample with fixed size, i.e. the number of mutations carried by k individuals in the sample. Explicit formulae for the expected frequency spectrum of a sample are provided, in the cases of a fixed foundation time, and of a uniform and log-uniform prior on the foundation time. Second, we establish the convergence in distribution, for large sample sizes, of the (suitably renormalized) tree spanned by the sample genealogy with prior g_i on the time of origin. We finally prove that the limiting genealogies with different priors can all be embedded in the same realization of a given Poisson point measure.
https://hal.archives-ouvertes.fr/hal-01053343

hal-01053343
https://hal.archives-ouvertes.fr/hal-01053343
ARXIV : 1407.7720

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Alkali feldspar thermochronologic modeling with the 40Ar/39Ar method has generated marked advances in knowledge of the mechanisms for argon diffusion in feldspars. While the goal in many cases has been to extrapolate the observed and modeled argon behavior in feldspars to natural geological settings, scientific debate surrounding the true feasibility of such extrapolations and indeed, the validity of thermochronologic modeling in itself, have provided much impetus to improve laboratory techniques to test, and increase basic understanding of, argon diffusion. Two cornerstones for the debate over the feasibility of alkali feldspar thermochronology for modeling natural, geologic processes have been: 1. is volume diffusion the main mechanism for argon movement in feldspars? and 2. if volume diffusion is a viable mechanism, does argon then reside in discrete ‘domains' within the feldspar lattice? We describe a study of alkali feldspars from a profile through a well-controlled brittle fault zone in western Norway; the feldspars document argon loss during deformation and strongly suggest the existence of argon ‘domains' within the feldspars, at least during laboratory step heating. The progressive change in the character of argon diffusion is recognizable in the logr/ro diffusion data from the feldspars and is mimicked by physical changes observed optically in the feldspars through progressive degrees of brittle deformation. Modeling results indicate a reduction in size of the biggest domains and the appearance of smaller domains during the strongest stages of deformation. Whether or not this reveals the existence and the transformation of the domain structure in naturo is difficult to prove from our data alone, but interestingly, this behaviour corresponds directly to the physical (optical) appearance of more intense crack networks and subgrains in progressively more brecciated feldspars. Because the thermochronologic histories derived from modeling the feldspar data conform very well to the known tectonic history of the area, the feldspars appear to have successfully retained physical (optical and isotopic) records of episodic tectonic processes operating from ductile through lowtemperature brittle regimes in rocks with a Caledonian history overprinted by several later (younger) geologic events. However, because the ‘cold' brecciation is the last tectonothermal event recorded by these rocks, it is impossible to truly test for the existence of diffusion domains in naturo. Argon loss appears to have been effective only in the most highly brecciated (deformed) samples where the combination of the connected crack network, increased fluid flow and higher temperatures enhanced diffusion via fast diffusion pathways and thus, volume diffusion from the lattice. Only minor argon loss occurred in zones of lower brittle strain, although some development of cracks and brittle features is evident. Independent of the existence of diffusion domains, this study highlights the possible pitfalls when cooling histories are deduced from brecciated feldspars in which age and diffusion charateristics have been decoupled: while the geochronological memory has survived and is identical to that of nonbrecciated feldspars (suggesting no loss and minor effects of deformation), the diffusion characteristics have been completely transposed by brecciation and the appearance of new domains. Modeling feldspars with these latter characteristics would effectively utilise a new feldspar diffusion structure with an ‘old' (relict) age memory.
ISSN: 0016-7037

hal-00198283
https://hal.archives-ouvertes.fr/hal-00198283
https://hal.archives-ouvertes.fr/hal-00198283/document
https://hal.archives-ouvertes.fr/hal-00198283/file/KsparBreccia_Arnaud_Eide_GCA_2000.pdf

Éditeur(s) : HAL CCSD Frontiers Media
Résumé : International audience
Coral reef fisheries support the development of local and national economies and are the basis of important cultural practices and worldviews. Transitioning economies, human development, and environmental stress can harm this livelihood. Here we focus on a transitioning social-ecological system as a case study (Moorea, French Polynesia). We review fishing practices and three decades of effort and landing estimates with the broader goal of informing management. Fishery activities in Moorea are quite challenging to quantify because of the diversity of gears used, the lack of centralized access points or markets, the high participation rates of the population in the fishery, and the overlapping cultural and economic motivations to catch fish. Compounding this challenging diversity, we lack a basic understanding of the complex interplay between the cultural, subsistence, and commercial use of Moorea's reefs. In Moorea, we found an order of magnitude gap between estimates of fishery yield produced by catch monitoring methods (2 t km −2 ∼ year −1) and estimates produced using consumption or participatory socioeconomic consumer surveys (∼24 t km −2 year −1). Several lines of evidence suggest reef resources may be overexploited and stakeholders have a diversity of opinions as to whether trends in the stocks are a cause for concern. The reefs, however, remain ecologically resilient. The relative health of the reef is striking given the socioeconomic context. Moorea has a relatively high population density, a modern economic system linked into global flows of trade and travel, and the fishery has little remaining traditional or customary management. Other islands in the Pacific in similar contexts in Polynesia such as Hawaii, that continue to develop economically, may have small-scale fisheries that increasingly resemble Moorea. Therefore, understanding Moorea's reef fisheries may provide insight into their future.
ISSN: 2296-7745

Droits : http://creativecommons.org/licenses/by/
hal-01325804
https://hal-univ-perp.archives-ouvertes.fr/hal-01325804
https://hal-univ-perp.archives-ouvertes.fr/hal-01325804/document
https://hal-univ-perp.archives-ouvertes.fr/hal-01325804/file/fmars-03-00070.pdf
DOI : 10.3389/fmars.2016.00070

Éditeur(s) : HAL CCSD Groupe français de géomorphologie (GFG)
Résumé : International audience
This study aims at assessing the vulnerability of populations in the Pasig-Potrero River basin, who are threatened by the recurrent lahars of Mt Pinatubo volcano (Philippines) in the aftermath of its 1991 eruption. A survey, carried out between February and March 1998, enabled us to define and to map different levels of risk perception, the quality of potential behavioural patterns in the event of further lahars, and attitudes in the event of an evacuation order. It was then possible to work out a classification and to map the patterns of human vulnerability in the study area. This study points out that, while risk perception is quite high, some problems remain, notably concerning the warning systems and the behaviour of the population in the case of an evacuation. Theses results should assist in elaborating risk and disaster scenarios. They are intended to be used for operational purposes in crisis management such as the organization of disaster relief, and in land use planning.
ISSN: 1266-5304

hal-01169334
https://hal.archives-ouvertes.fr/hal-01169334
https://hal.archives-ouvertes.fr/hal-01169334/document
https://hal.archives-ouvertes.fr/hal-01169334/file/article_morfo_1266-5304_2001numéro 7_3_1103.pdf
DOI : 10.3406/morfo.2001.1103

Éditeur(s) : Inter-research
Résumé : Marine protected areas (MPAs) have the potential to enhance the long-term sustainability of coastal resources, and the artisanal fisheries which depend on them. However, recreational fisheries, which are increasing their impacts on coastal resources worldwide, may reduce the benefits that MPAs provide to declining artisanal fisheries. Here we used the Bonifacio Straits Natural Reserve (BSNR) Corsica as a study case to simulate the combined effects on coastal resources of artisanal and recreational fishing efforts. The BSNR ecosystem was modelled using mass-balance modelling of trophic interactions. This model was compared to another built on a non-protected area from the same region. We aggregated fishing fleets into artisanal and recreational categories, and we simulated various combinations of fishing effort over a 20 yr dynamic simulation using Ecosim. We showed that fishing activities have an additional top-down effect on the food web and that they decrease the targeted group's biomass, such as piscivorous species. We found, for some trophic groups, non-trivial patterns of biomass variation through trophic cascades. Our trophic approach revealed that some groups may suffer a biomass decrease when MPAs are set or enforced, due to the combined effect of artisanal and recreational fisheries. Overall, our results illustrate the value of modelling to manage MPAs, as a complementary tool to surveys. Models provide the opportunity to anticipate the potential consequences, at the ecosystem level, of socio-political decisions that aim to sustain coastal resources while managing artisanal and recreational fisheries.
Marine Ecology-progress Series (0171-8630) (Inter-research), 2010-08 , Vol. 412 , P. 207-221

Droits : Inter-Research 2010
http://archimer.ifremer.fr/doc/00013/12436/9246.pdf
http://archimer.ifremer.fr/doc/00013/12436/9247.pdf
DOI:10.3354/meps08679
http://archimer.ifremer.fr/doc/00013/12436/

Éditeur(s) : HAL CCSD
Résumé : We introduce a general context involving a presheaf A and a subpresheaf B of A. We show that all previously considered cases of local analysis of generalized functions (defined from duality or algebraic techniques) can be interpretated as the B-local analysis of sections of A. But the microlocal analysis of the sections of sheaves or presheaves under consideration is dissociated into a "frequential microlocal analysis " and into a "microlocal asymptotic analysis". The frequential microlocal analysis based on the Fourier transform leads to the study of propagation of singularities under only linear (including pseudodifferential) operators in the theories described here, but has been extended to some non linear cases in classical theories involving Sobolev techniques. The microlocal asymptotic analysis can inherit from the algebraic structure of B some good properties with respect to nonlinear operations.
https://hal.archives-ouvertes.fr/hal-00190006

Droits : info:eu-repo/semantics/OpenAccess
hal-00190006
https://hal.archives-ouvertes.fr/hal-00190006
https://hal.archives-ouvertes.fr/hal-00190006/document
https://hal.archives-ouvertes.fr/hal-00190006/file/Regularity-Local-Microlocal-Analysis5.pdf
ARXIV : 0711.3688

Éditeur(s) : HAL CCSD
Résumé : International audience
An iterative method for solving set-valued variational inequalities is considered and its convergence properties are studied under strong monotonicity and coercivity conditions. The results obtained in this paper include, as a special case, some known results in this field.
Mathematical Inequalities & Applications

hal-00776616
https://hal.univ-antilles.fr/hal-00776616

Éditeur(s) : HAL CCSD Springer Verlag (Germany) Springer Verlag
Résumé : International audience
The dissolution of carbonate rocks usually leads to both porosity (ϕ) and permeability (k) increase. We present experimental evidences and physical-based models of positive and anti-correlated dynamics of k and ϕ observed during dissolution experiments of carbonate rocks. We study the way the rate of change of ϕ and k is controlled by the degree of undersaturation of the percolating solution for two different types of carbonate rocks. We document the occurrence of an anti-correlated k−ϕ trend when the flowing fluid (deionized water) has a weak capacity of dissolution. A positive correlation is found when CO2 is added to the deionized water to increase the potential dissolution rate. Detailed analyses of the microstructures of the rock performed by X-ray microtomography reveal that low dissolution rate favors detachment of solid particles and their subsequent accumulation at the pore-throat inlet. Particles are detached from the rock matrix due to the differential dissolution rate of the indurated grains and the microporous cement. We then propose a simple phenomenological model to interpret the effect of the pore-throat clogging by the accumulation of partially dissolved carbonate particles. We conjecture that permeability is controlled by the decrease of the effective hydraulic radius and the increase of the tortuosity due to partial and localized obstruction of the pore network. Conversely, increasing the level of undersaturation of the flowing solution leads to an augmented potential of dissolving most of the transported particles before they reach the throats. In this case, both k and ϕ increase and display power-law correlations.
ISSN: 0169-3913

hal-01174145
https://hal.archives-ouvertes.fr/hal-01174145
DOI : 10.1007/s11242-015-0456-2

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
3D seismic data located in the Gjallar Ridge (Vøring Basin, offshore Norway) reveals a closely-spaced polygonal fault system affecting more than 800 m of homogeneous mud-dominated Quaternary and Tertiary sequences. As some faults reach the modern seafloor, they represent an active polygonal fault system at present day. Even if the processes remain unclear and are still under debate, it is generally agreed that the initiation of polygonal faults is the result of shallow burial dewatering of fine-grained unconsolidated sediments by volumetric compaction. 3D seismic data are commonly interpreted by propagating horizons automatically and by picking faults manually. However, in the case of polygonal fault intervals, this approach is time consuming due to the huge number of faults and because automatic propagation can be misleading. In this study, we applied a new technique of 3D seismic interpretation based on a sequential stratigraphy analysis, using the new PaleoScan© software (Eliis Company). It allowed us to build a 3D geological model computing more than 300 horizons within the faulted intervals. We then used the coherency attribute, depicting anomalies in the shape of seismic waveform like faults, in order to constrain a possible link between fault distribution and stratigraphic levels. Our approach allows fault throws to be calculated in milliseconds on any polygonal fault plane. The result shows that fault segments have been reactivated by dip-linkage. Distribution of faults depends on mechanical units, intervals characterized by different petrophysical properties, which are independent from lithological and diagenetic changes. According to these results, we propose a model showing the evolution of polygonal fault intervals in which faulting stages are separated by a quiescence phase during burial. A first tier of polygonal faults is initiated at a specific depth, according to the Cam-clay model. Then, following a period of quiescence during which mud-rich sediments continued to accumulate, new fault segments are initiated above the first mechanical unit and within this undeformed interval. New nucleated faults then connect downward to pre-existing underlying polygonal fault system, thus progressively increasing the thickness of the faulted interval.
ISSN: 0025-3227

hal-00772470
https://hal.archives-ouvertes.fr/hal-00772470
DOI : 10.1016/j.margeo.2012.07.016

Éditeur(s) : HAL CCSD Société Géologique de France
Résumé : The Udachnaya-East pipe in Yakutia in Siberia hosts a unique dry (serpentine-free) body of hypabyssal kimberlite (<0.64wt% H2O), associated with a less dry type of kimberlite and a serpentinized kimberlitic breccia. The dry kimberlite is anomalously rich in salts (Na2O and Cl both up to 6wt%) whereas the slightly less dry and the breccia kimberlite are salt free. Yet the Udachnaya kimberlite is a group-I kimberlite, as is the archetypical kimberlite from Kimberley, South Africa. Samples were studied from the three different types of kimberlite (dry-salty, n=8, non-salty, n=5 and breccia, n=3) regarding their mineralogy, geochemistry, and more specifically their sulfur content. Our results show the salty kimberlite is unprecedentedly rich in sulfur (0.13-0.57wt%) compared to the non-salty kimberlite (0.04-0.12wt%) and the breccia (0.29-0.33wt%). In the salty kimberlite, most of the sulfur is present as sulfates (up to 97% of Stotal) and is disseminated throughout the groundmass in close association with Na-K-bearing carbonates. Sulfates occur within the crystal structure of these Na-K-bearing carbonates as the replacement of (CO3) by (SO3) groups, or as Na- and K-rich sulfates (e.g. aphtitalite, (K,Na)3Na(SO4)2). The associated sulfides are djerfisherite; also Na- and K-rich species. The close association of sulfates and carbonates in these S-rich alkaline rocks suggests that the sulfates crystallized from a mantle-derived magma, a case that has strong implication for the oxygen fugacity of kimberlite magmatism and more generally for the global S budget of the mantle.
ISSN: 0037-9409

hal-01622633
https://hal.archives-ouvertes.fr/hal-01622633
DOI : 10.1051/bsgf/2017007

Éditeur(s) : Gauthier-Villars
Résumé : The fish assemblages of two artificial reef systems of the south coast of Algarve (Portugal) are presented, and a comparative study is made of their species richness variation according to their location off the Ria Formosa lagoon. Each system consists of a protection reef and an exploitation reef. Gillnets, traps, longline and visual census were used as sampling techniques. Both reefs showed similar species richness, in each case higher than that of Ria Formosa. No significant differences of species richness were found between the reef systems (p = 0.1). However, the exploitation reefs showed a significant difference of species richness, that was more evident when accumulated species richness was used to compare them (p = 0.01).
Oceanologica Acta (0399-1784) (Gauthier-Villars), 1996 , Vol. 19 , N. 1 , P. 89-97

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00096/20764/18390.pdf
http://archimer.ifremer.fr/doc/00096/20764/

Éditeur(s) : HAL CCSD
Résumé : LPSC14037
Scientific data collected with modern sensors or dedicated detectors exceed very often the perimeter of the initial scientific design. These data are obtained more and more frequently with large material and human efforts. A large class of scientific experiments are in fact unique because of their large scale, with very small chances to be repeated and to superseded by new experiments in the same domain: for instance high energy physics and astrophysics experiments involve multi-annual developments and a simple duplication of efforts in order to reproduce old data is simply not affordable. Other scientific experiments are in fact unique by nature: earth science, medical sciences etc. since the collected data is "time-stamped" and thereby non-reproducible by new experiments or observations. In addition, scientific data collection increased dramatically in the recent years, participating to the so-called "data deluge" and inviting for common reflection in the context of "big data" investigations. The new knowledge obtained using these data should be preserved long term such that the access and the re-use are made possible and lead to an enhancement of the initial investment. Data observatories, based on open access policies and coupled with multi-disciplinary techniques for indexing and mining may lead to truly new paradigms in science. It is therefore of outmost importance to pursue a coherent and vigorous approach to preserve the scientific data at long term. The preservation remains nevertheless a challenge due to the complexity of the data structure, the fragility of the custom-made software environments as well as the lack of rigorous approaches in workflows and algorithms. To address this challenge, the PREDON project has been initiated in France in 2012 within the MASTODONS program: a Big Data scientific challenge, initiated and supported by the Interdisciplinary Mission of the National Centre for Scientific Research (CNRS). PREDON is a study group formed by researchers from different disciplines and institutes. Several meetings and workshops lead to a rich exchange in ideas, paradigms and methods. The present document includes contributions of the participants to the PREDON Study Group, as well as invited papers, related to the scientific case, methodology and technology. This document should be read as a "facts finding" resource pointing to a concrete and significant scientific interest for long term research data preservation, as well as to cutting edge methods and technologies to achieve this goal. A sustained, coherent and long term action in the area of scientific data preservation would be highly beneficial.
http://hal.in2p3.fr/in2p3-00959072

in2p3-00959072
http://hal.in2p3.fr/in2p3-00959072
http://hal.in2p3.fr/in2p3-00959072/document
http://hal.in2p3.fr/in2p3-00959072/file/PREDON_Scientific_Data_Preservation_2014.pdf

Éditeur(s) : HAL CCSD
Résumé : International audience
This paper investigates the narrative challenges and opportunities that contemporary virology offers to popular science and to fiction. The study of viruses reveals extremely complex relations, playing out over different physical and temporal scales. Viruses constitute a heterogeneous population whose interactions with living organisms occur on multiple levels, and whose numbers are vastly superior to human and even bacterial populations on earth. The resulting challenges for narration can be grouped into three main formal questions. The first is the problem of scale, since the numbers and sizes of virus and host populations are vastly different, as are the temporalities over which they transform and survive. The second is the complexity of actants, since viruses are involved in relations where destruction and mutual benefit can overlap, and genetic transformations are played out over many generations. The third is the choice of images through which to convey their behaviours: many existing metaphors in microbiology, such as “chimeras”, “parasites” or “kill-the-winner dynamics”, carry the narrative potential of a mythological and/or theatrical imagination.These questions will first be examined as challenges encountered in the narration of biology for vulgarization purposes, and effects on narrative forms will be outlined: shifts in focalization in order to create multiscalar perspectives; unstable actantial models as expressions of complex relations; and the use or resistance to narrative structures implied by several key metaphors in virological discourse. These formal characteristics will then be presented through two case studies drawn from contemporary fiction. In his “scientific fable” Conflits Intérieurs (2015), microbiologist Eric Bapteste creates a multiscalar narrative by using humans and viruses as both protagonists and narrators in a battle of ideas. In the graphic novel aâma (2011-2014), Frederik Peeters explores the ambiguous potential, both symbiotic and threatening, of a meta-organism uniting humans with microscopic agents. Both these novels play with scale, metaphor and actants so as to question the fundaments of human identity. They posit the act of narration as a defining human attribute, and consequently use the narrative voice as an arena in which we observe the weakening of the notion of the subject by microbiology.
“Narrative, Cognition & Science” Symposium
Erlangen, Germany

hal-01434744
https://hal.archives-ouvertes.fr/hal-01434744

Éditeur(s) : HAL CCSD BOKU - University of Natural Resources and Applied Life Sciences
Résumé : International audience
Our paper is based on the first results of a twofold interdisciplinary research project financed by the French Ministry of the Environment (DIVA2 programme) which purpose was to analyse the emergence of biodiversity conservation as a new goal set to geographical indications and to study its effects on the strategies of the various stakeholders, and their impacts on the farming practices and the...
Building sustainable rural futures: the added value of systems approaches in times of change and uncertainty. 9th European IFSA Symposium, Vienna, Austria, 4-7 July 2010.
Vienna, Austria

hal-00979640
https://hal-agroparistech.archives-ouvertes.fr/hal-00979640

Éditeur(s) : HAL CCSD
Résumé : International audience
Numerous diffusion models can be found in the literature. Although these models havebeen widely used to address several problems related to diffusion phenomena at the individuallevel, they do not faithfully represent the microscopic mechanisms that take place in the realtransmission processes. Today, the apparition of new communication media allows model togo further by providing data on many real cases of diffusion. In particular, these newapproaches have shown that several dimensions involved in diffusion phenomena are notpresent in current models. In our works, we focus on two original dimensions to address thediffusion problem: the personality and the neutrality of the spreader. Our aim is to understandthe influence of these two dimensions regarding the diffusion behaviours. Our approach hasbeen used to study diffusion of messages related to several events occurred in January 2015.The results obtained provide a new and interesting lighting on the heterogeneity of thediffusion behaviors in function of personality and neutrality levels. This work provides amethodology which may be useful in marketing strategies, for instance the analysis of thefeatures of individuals who talk about their touristic trips in Caribbean. Such an approach mayalso be useful to understand diffusion and exchange behaviors in the Caribbean basin. Froman economic point of view, such an approach could be used for understanding theexpectations, targeting individuals and proposing tailored offers.
20th Biennial General Meeting of The Caribbean Academy of Sciences
Deshaies, France

hal-01514262
https://hal.archives-ouvertes.fr/hal-01514262

Éditeur(s) : HAL CCSD Oxford University Press (OUP)
Résumé : International audience
Functional ecology has long considered the support function as important, but its biomechanical complexity is only just being elucidated. We show here that it can be described on the basis of four biomechanical traits, two safety traits against winds (SW) and self-buckling (SB), and two motricity traits involved in sustaining an upright position, tropic motion velocity (MV) and posture control (PC). All these traits are integrated at the tree scale, combining tree size and shape together with wood properties. The assumption of trait constancy has been used to derive allometric scaling laws, but it was more recently found that observing their variations among environments and functional groups, or during ontogeny, provides more insights into adaptive syndromes of tree shape and wood properties. However, over-simplified expressions have often been used, possibly concealing key adaptive drivers. An extreme case of over-simplification is the use of wood basic density as a proxy for safety. Actually, since wood density is involved in stiffness, loads and construction costs, the impact of its variations on safety is non-trivial. Moreover, other wood features, especially the microfibril angle (MFA), are also involved. Furthermore, wood is not only stiff and strong, but it also acts as a motor for MV and PC. The relevant wood trait for that is maturation strain asymmetry. Maturation strains vary with cell wall characteristics such as MFA, rather than with wood density. Finally, the need for further studies about the ecological relevance of branching patterns, motricity traits and growth responses to mechanical loads is discussed.
ISSN: 0022-0957

hal-00909904
https://hal.archives-ouvertes.fr/hal-00909904
https://hal.archives-ouvertes.fr/hal-00909904/document
https://hal.archives-ouvertes.fr/hal-00909904/file/Integrative_biomechanics_for_tree_Fournier_al.pdf
DOI : 10.1093/jxb/ert279

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
BackgroundMalaria is endemic in French Guiana, an overseas territory of France on the Guiana Shield. Since 2005, notified malaria cases are decreasing. However, new data show that malaria affects many Brazilian gold miners working illegally in French Guiana, the majority of whom are not counted in official data. In addition, one major concern is the usual practice of improper self-treatment in this mining population, raising fear of the development of antimalarial resistance. This prospective study, conducted in 2015, aimed to estimate the prevalence of Plasmodium spp. in illegal gold miners working in French Guiana. MethodsThe recruitment of gold miners was carried out in resting sites along the French Guiana-Suriname border, where they go for supplies, medical care or leisure. After recording agreement, three malaria diagnostic methods were performed: rapid diagnostic test, microscopy and PCR,ResultsAmong 421 persons recruited in the study, malaria prevalence, detected by nested-PCR, was 22.3% (CI=[18.3-26.3], n=94/421) of which 84% were asymptomatic. ConclusionThis significant malaria reservoir in a mobile and illegal population with difficult access to a health care system raises the threat of artemisinin resistance and puts the population of the Guiana Shield at risk of new transmission foci while countries of the region aim at malaria elimination. Even though French legislation may hamper dealing with this population, France must face the reality of malaria in illegal gold miners in order to meet its commitment to malaria elimination.
ISSN: 1475-2875

hal-01346800
https://hal.archives-ouvertes.fr/hal-01346800
https://hal.archives-ouvertes.fr/hal-01346800/document
https://hal.archives-ouvertes.fr/hal-01346800/file/2016%2C%20Douine%20-%20Prevalence%20of%20Plasmodium%20spp.%20in%20illegal%20gold%20miners%20in%20French%20Guiana%20in%202015.pdf
DOI : 10.1186/s12936-016-1367-6

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
A comprehensive inventory of global biodiversity would be greatly improved by automating methods for species delimitation. The Automatic Barcode Gap Discovery method, the Poisson tree processes algorithm and the Generalized mixed Yule coalescent model have been proposed as means of increasing the rate of biodiversity description using single locus data. We applied these methods to explore the diversity within the Aglaopheniidae, a hydrozoan family with many species widely distributed across tropical and tem perate oceans. Our analyses revealed widespread cryptic diversity in this family, almost half of the morpho species presenting several independent evolutionary lineages, as well as support for cases of synonymy. For two common species of this family, Lytocarpia brevirostris and Macrorhynchia phoenicea, we compared the outputs to clustering analyses based on microsatellite data and to nuclear gene phylo genies. For L. brevirostris, microsatellite data were congruent with results of the species delimitation methods, revealing the existence of two cryptic species with Indo Pacific distribution. For M. phoenicea, all analyses confirmed the presence of two cryptic species within the South Western Indian Ocean. Our study suggests that the diversity of Aglaopheniidae might be much higher than assumed, likely related to low dispersal capacities. Sequence based species delimitation methods seem highly valuable to reveal cryptic diversity in hydrozoans; their application in an integrative framework will be very useful in describing the phyletic diversity of these organisms.
ISSN: 1055-7903

hal-01359407
https://hal.archives-ouvertes.fr/hal-01359407
https://hal.archives-ouvertes.fr/hal-01359407/document
https://hal.archives-ouvertes.fr/hal-01359407/file/Postaire-etal2016MolPhylEvol_sp_delim_hydraires_HAL.pdf
DOI : 10.1016/j.ympev.2016.08.013

Éditeur(s) : HAL CCSD
Résumé : International audience
The aim of this study is to perform a simulation of large scale Wireless Sensor Networks (WSN) working on medical diagnosis. The main feature of this WSN is its density and the fact that all sensors are in the same radio range. Our approach helps medical staff to diagnose diseases in an automatic way. In this context, each patient is equipped to a set of sensors. Each sensor is connected to a transducer dedicated to measure a specific health parameter . This WSN will perform some computations and run an alarm when some diseases are suspected. This technique is based on the population protocol to handle data exchanged between sensors. This approach is in fact an efficient distributed algorithm which implies that the diagnose may be done by any sensor dealing with the disease detection. The main result of this paper is: the method supports large scalability which proves its practicability for real cases.
Computers and Communications (ISCC), 2010 IEEE Symposium on Computers and Communications.
Riccione, Italy

hal-00519595
https://hal.archives-ouvertes.fr/hal-00519595