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One of the many ecosystem services provided by dung beetles is that of secondary seed dispersal. This paper experimentally evaluates the effectiveness of this service using the chimpanzee–dung beetle seed dispersal system in Taï National Park, Côte d’Ivoire. The study focussed on the germination rate and success of four species of seeds contained in the faeces ofPan troglodytes verus: Dacryodes klaineana(Pierre) H.J. Lam,Diospyros manniiHiern,Pycnanthus angolensis(Welw.) Warb., andUapaca guineensisMuell. Arg. For each species, 600 seeds, half from chimpanzee faeces and half from mother trees, were sown in nurseries at depths of 0, 2, 5, 10, and 15 cm (i.e. 120 seeds per depth; 60 from chimp and 60 from mother trees). After germination, only the seeds ofUapaca guineensisandDiospyros manniisown at 2 and 5 cm had a >14% rate (between 14.2 and 30.8%) of germination and seedling establishment, regardless of seed origin. An increase in the depth of seed burial appears to negatively affect the probability of seedling emergence and establishment. This study shows that dung beetles have positive impacts on seed fate. However, for these plant species, the chimpanzee’s role is limited to that of primary seed dispersal.

The status of the Scarabaeus (Scarabaeus) species belonging to the gangeticus group is studied. Ateuchus (Heliocantharus) profanus Boheman, 1857, Scarabaeus nepos Fairmaire, 1884, and Scarabaeus laevigatus Kolbe, 1887, are retained as good species and their status restored. A lectotype is designed for Scarabaeus pacatus Péringuey 1901, which is synonymized with Ateuchus (Heliocantharus) profanus Boheman, 1857. The holotype by monotypy of Ateuchus gangeticus Castelnau, 1840, est identifié. A lectotype is designed for Ateuchus isidis Castelnau, 1840. To fix the taxonomy, a neotype is designed for Ateuchus goryi Castelnau, 1840, for which the type is considered lost. Scarabaeus pseudogangeticus Moretto n. sp., Scarabaeus osiridis Moretto n. sp., Scarabaeus montreuili Moretto n. sp. and et Scarabaeus montreuili meridionalis Moretto n. ssp. are described. The morphological characters used to separate the species are specified, described and illustrated. An identification key and distribution maps are produced. The holotype by monotypy of Ateuchus jalof Castelnau, 1840, is identified; this species is removed from the S. gangeticus species group and transferred in S. transcaspicus species group., Le statut des espèces de Scarabaeus (Scarabaeus) du groupe gangeticus est étudié. Ateuchus (Heliocantharus) profanus Boheman, 1857, Scarabaeus nepos Fairmaire, 1884, et Scarabaeus laevigatus Kolbe, 1887, sont retenus comme bonnes espèces et leur statut restauré. Un lectotype est désigné pour Scarabaeus pacatus Péringuey 1901, qui est mis en synonymie avec Ateuchus (Heliocantharus) profanus Boheman, 1857. L’holotype par monotypie d’Ateuchus gangeticus Castelnau, 1840, est identifié. Un lectotype est désigné pour Ateuchus isidis Castelnau, 1840. Pour fixer la taxonomie, un néotype est désignés pour Ateuchus goryi Castelnau, 1840, dont le type est considéré comme perdu. Scarabaeus pseudogangeticus Moretto n. sp., Scarabaeus osiridis Moretto n. sp., Scarabaeus montreuili Moretto n. sp. et Scarabaeus montreuili meridionalis Moretto n. ssp. sont décrits. Les caractères morphologiques utilisés pour séparer les espèces sont précisés, décrits et illustrés. Une clé d’identification et des cartes de répartition sont produites. L’holotype par monotypie d’Ateuchus jalof Castelnau, 1840, est identifié ; cette espèce est écartée du groupe de S. gangeticus et transférée dans le groupe de Scarabaeus transcaspicus Stolfa, 1938.

Seed dispersal is a key stage in the life cycle of plants, thus in forest regeneration, especially in the tropics. Chimpanzees are known as important seed dispersers and dung beetles play critical roles in secondary dispersal thus increasing the chance for seed post-dispersal success. Hence, understanding secondary seed dispersal by dung beetles is critical to our understanding of forest dynamics and seedling establishment. The aim of this study was to evaluate the effects of successive seed dispersal by chimpanzees and by dung beetles on the surface dispersal and burial of the seeds of four plant species: (Dacryodes klaineana, Diospyros mannii, Pycnanthus angolensis and Uapaca guineensis) at three nesting site in the Taï National Park. To investigate this, 28 seeds i.e. seven seeds per plant species (N = 75, average ± SD: 28.24 ± 3.06 seeds) were introduced into 85 g of chimpanzee faeces. This set was exposed on the forest floor for 48h following an average faeces radius of 5 cm (N = 40, average ± SD: 5 ± 1.06 cm). From the observations made, it emerges an essentially surface dispersion, ie 45.6% of the seeds dispersed against 6.3% of seeds buried. The highest rate of vertically dispersed seeds, ie 10.31%, and average depth of burial, ie 7.45 cm, were quantified in the Southern nesting sites. This distribution of seeds would not only be linked to the time of deposition of the faeces, but also and above all to the size of the secondary disperser.

Seed dispersal is a key stage in the life cycle of plants, thus in forest regeneration, especially in the tropics. Chimpanzees are known as important seed dispersers and dung beetles play critical roles in secondary dispersal thus increasing the chance for seed post-dispersal success. Hence, understanding secondary seed dispersal by dung beetles is critical to our understanding of forest dynamics. The aim of this study was to evaluate the effects of successive dispersal by chimpanzees and by dung beetles on the surface dispersal and burial of the seeds of four plant species: (Dacryodes klaineana (Pierre) H.J. Lam, Diospyros mannii Hiern, Pycnanthus angolensis (Welw.) Warb. and Uapaca guineensis Muell) at three nesting site in the Taï National Park. To investigate this, 28 seeds i.e. seven seeds per plant species (N = 75, average ± SD: 28.24 ± 3.06 seeds) were introduced into 85 g of chimpanzee faecal matter. This set was exposed on the forest floor for 48h following an average faecal radius of 5 cm (N = 40, average ± SD: 5 ± 1.06 cm). From the observations made, it emerges an essentially surface dispersion, ie 45.6% of the seeds dispersed against 6.3% of seeds buried. The highest rate of vertically dispersed seeds, ie 10.31%, and average depth of burial, ie 7.45 cm, were quantified in the southern nesting sites. This distribution of seeds would not only be linked to the time of deposition of the faecal matter, but also and above all to the size of the secondary disperser.

Heliocopris ares n. sp. is decribed from India and Sri Lanka and compared to Heliocopris bucephalus (Fabricius, 1775). The distribution of the two species is detailed and a map is produced. The status of the presumed synonyms of Scarabaeus bucephalus Fabricius, 1775, currently Heliocopris bucephalus (Fabricius, 1775) – Copris tmolus Fischer, 1822, and Scarabaeus cristatus De Geer, 1778 – is examined and clarified. Scarabaeus cristatus De Geer, 1778, is a new synonym of Scarabaeus hamadryas Fabricius, 1775, currently Heliocopris hamadryas (Fabricius, 1775), an African species. All treated species are illustrated., Heliocopris ares n. sp. est décrit d’Inde et du Sri Lanka et comparé à Heliocopris bucephalus Fabricius, 1775. La répartition des deux espèces est précisée et une carte produite. Le statut des synonymes supposés de Scarabaeus bucephalus Fabricius, 1775, actuellement Heliocopris bucephalus (Fabricius, 1775) – Copris tmolus Fischer, 1822, et Copris cristatus De Geer, 1778 – est examiné et explicité. Copris cristatus De Geer, 1778, est un nouveau synonyme de Scarabaeus hamadryas Fabricius, 1775, actuellement Heliocopris hamadryas (Fabricius, 1775), une espèce africaine. Toutes les espèces traitées sont illustrées.

Onitis albertcollartisp. nov. is described and illustrated. The new species is closely related to and occurs sympatrically with O. lycophron Klug, 1855.

Aim: While elevational gradients in species richness constitute some of the best depicted patterns in ecology, there is a large uncertainty concerning the role of food resource availability for the establishment of diversity gradients in insects. Here, we analysed the importance of climate, area, land use and food resources for determining diversity gradients of dung beetles along extensive elevation and land use gradients on Mt. Kilimanjaro, Tanzania. Location: Mt. Kilimanjaro, Tanzania. Taxon: Scarabaeidae (Coleoptera). Methods: Dung beetles were recorded with baited pitfall traps at 66 study plots along a 3.6 km elevational gradient. In order to quantify food resources for the dung beetle community in form of mammal defecation rates, we assessed mammalian diversity and biomass with camera traps. Using a multi‐model inference framework and path analysis, we tested the direct and indirect links between climate, area, land use and mammal defecation rates on the species richness and abundance of dung beetles. Results: We found that the species richness of dung beetles declined exponentially with increasing elevation. Human land use diminished the species richness of functional groups exhibiting complex behaviour but did not have a significant influence on total species richness. Path analysis suggested that climate, in particular temperature and to a lesser degree precipitation, were the most important predictors of dung beetle species richness while mammal defecation rate was not supported as a predictor variable. Main conclusions: Along broad climatic gradients, dung beetle diversity is mainly limited by climatic factors rather than by food resources. Our study points to a predominant role of temperature‐driven processes for the maintenance and origination of species diversity of ectothermic organisms, which will consequently be subject to ongoing climatic changes.

A necro-coprophagous new genus tha is widespread in the whole Sub-Saharan Africa was identified within the tribe Onthophagini and named Tiaronthophagus n.gen. The new genus, which is well characterized by an exclusive set of characters, comprises, at present, 26 species. Twenty species were formerly included in the genus Onthophagus and six were identified and here described as new species: Tiaronthophagus angolensis n.sp., T. jossoi n.sp., T. katanganus n.sp., T. rolandoi n.sp., T. saadaniensis n.sp., and T. zambesianus n.sp. A phylogenetic analysis that is based on a combined matrix, including discrete and landmark characters, was done. The landmark characters were tested using the geometric morphometrics techniques before their inclusion in the matrix. One single, fully resolved tree was obtained, with Tiaronthophagus constituting a distinct, monophyletic clade within Onthophagini, which was clearly separated from the other genera examined here. The biogeographical analysis identified the Central Africa as the ancestral area of the new genus and it mainly accounted for dispersal events leading to the present distribution. The generic rank that is assigned to the taxon is supported by the results of the morphological, phylogenetic, and biogeographical analyses, and by the comparison to the outgroups.

The taxonomy and systematics of the genus Digitonthophagus Balthasar (Coleoptera: Scarabaeidae: Scarabaeinae: Onthophagini) is revised. A detailed study of the male genitalia combined with external morphology suggests that the variability, previously recognized, for D. gazella is hiding a species complex within the Afrotropical region and the Arabian Peninsula. The current study recognizes 16 species; 13 from the Afrotropical region and Arabian Peninsula and three from the eastern portion of the Saharo-Arabian region and the continental Indomalayan region. Species are organized into six species groups based on the results of the morphology-based phylogenetic analysis. The following 12 species are described as new: D. aksumensis Genier new species; D. biflagellatus Genier new species; D. dilatatus Genier new species; D. eucatta Genier new species; D. falciger Genier new species; D. fimator Genier new species; D. namaquensis Genier new species; D. petilus Genier new species; D. sahelicus Moretto new species; D. uk s Genier new species; D. ulcerosus Genier new species; and D. viridicollis Genier new species. In order to stabilize nomenclature, lectotypes are designated for Scarabaeus bonasus Fabricius, 1775; Scarabaeus catta Fabricius, 1787, and Onthophagus gazella lusinganus d’Orbigny. A neotype is designated for Scarabaeus dorcas Olivier, 1789 whose status and synonymy need to be altered in order to clarify the status of Scarabaeus gazella auctorum, the widely introduced species with economic importance. A naming scheme is presented for the sclerites of the internal sac. External and male genitalia are illustrated and distribution maps are provided for each species.

International audience; The provenance of 37 obsidians from the Kerkennah Islands (central Mediterranean Sea) was determined by PIXE. It is shown that they came from the two main obsidian sources, Balata dei Turchi and Lago di Venere, of the Pantelleria Island. A comparison of the PIXE elemental composition of geological vs. archaeological obsidians of central and western Mediterranean shows that their sources present elemental compositions homogeneous enough to make possible sourcing studies. However, a comparison between the distributions of geological and archaeological obsidians chemistry shows that the PIXE source qualifications do not cover yet the whole of their internal variations.

For endozoochorous seed dispersal systems, the extant dung beetle assemblage at seed deposition sites may influence site suitability as burial activity may change the probability that seeds germinate and seedlings establish. This study tested if the different conditions of the two main seed-deposition habitats of a western lowland gorilla population of south-east Cameroon (sleeping sites and old secondary forest) influenced dung beetle assemblages and consequently the seed relocation patterns. In March 2012, in both habitats, burial patterns (proportion and depth) were described in eight stations based on two 300-g experimental faeces with known number of Uapaca spp. seeds (N = 75) left for 48 h, and beetle assemblages were described based on one 48h-dung-baited pitfall trapping session in five of these stations. To assess the impact of burial pattern on seedling emergence, Uapaca seedling emergence trials were performed in a nursery (75 seeds per depth treatment). Assemblage at sleeping sites had a higher species richness (non-significant) and was significantly more abundant than in old secondary forests. Conversely, significantly more seeds were buried in old secondary forests than sleeping sites and at significantly greater depths (mean: 14.9 cm vs. 8.7 cm). As trials suggested that burial depth ≥7 cm prevented Uapaca seedling emergence, dung beetles are assumed to induce seed loss more strongly in old secondary forests than sleeping sites (20.5% vs. 6.7% of initial seed crop). The demonstration that dung beetles may exert a negative influence on seed fate overall, and that the degree to which this occurs may vary depending on habitat, highlights the complexity in determining the suitability of deposition sites for recruitment.

Purpose: TheGEANT4 general-purpose Monte Carlo simulation toolkit is able to simulate physical interaction processes of electrons, hydrogen and helium atoms with charge states ( H 0 , H + ) and ( He 0 , He + , He 2 + ), respectively, in liquid water, the main component of biological systems, down to the electron volt regime and the submicrometer scale, providing GEANT4 users with the so-called “GEANT4-DNA” physics models suitable for microdosimetry simulation applications. The corresponding software has been recently re-engineered in order to provide GEANT4 users with a coherent and unique approach to the simulation of electromagnetic interactions within the GEANT4 toolkit framework (since GEANT4 version 9.3 beta). This work presents a quantitative comparison of these physics models with a collection of experimental data in water collected from the literature. Methods: An evaluation of the closeness between the total and differential cross section models available in theGEANT4 toolkit for microdosimetry and experimental reference data is performed using a dedicated statistical toolkit that includes the Kolmogorov–Smirnov statistical test. The authors used experimental data acquired in water vapor as direct measurements in the liquid phase are not yet available in the literature. Comparisons with several recommendations are also presented. Results: The authors have assessed the compatibility of experimental data withGEANT4microdosimetry models by means of quantitative methods. The results show that microdosimetric measurements in liquid water are necessary to assess quantitatively the validity of the software implementation for the liquid water phase. Nevertheless, a comparison with existing experimental data in water vapor provides a qualitative appreciation of the plausibility of the simulation models. The existing reference data themselves should undergo a critical interpretation and selection, as some of the series exhibit significant deviations from each other. Conclusions: TheGEANT4-DNA physics models available in the GEANT4 toolkit have been compared in this article to available experimental data in the water vapor phase as well as to several published recommendations on the mass stopping power. These models represent a first step in the extension of the GEANT4 Monte Carlo toolkit to the simulation of biological effects of ionizing radiation.

We report on a comparative study by Transmission Electron Microscopy (HRTEM) and Scanning Transmission Ion Microscopy (STIM) combined with Rutherford Backscattering Spectrometry (RBS) and Particle Induced X-Ray Emission (PIXE) on ultra-thin and thin cross-sections, respectively, of various skin samples (porcine skin, healthy human skin, human skin grafted on a severe combined immuno-deficient mouse model) to which we applied topically various formulations containing titanium dioxide (TiO2) nanoparticles with primary particle sizes in the range from 20-100 nm. Whereas the HRTEM and STIM/PIXE images reveal clear differences - mainly related to the different thickness of the cross-sections - they unambiguously show that penetration of TiO2 nanoparticles is restricted to the topmost 3-5 corneocyte layers of the stratum corneum (SC).

New physical processes specific for microdosimetry simulation are under development in the Geant4 Low Energy Electromagnetic package. The first set of models implemented for this purpose cover the interactions of electrons, protons and light ions in liquid water; they address a physics domain relevant to the simulation of radiation effects in biological systems, where water represents an important component. The design developed for effectively handling particle interactions down to a low energy scale and the physics models implemented in the first public release of the software are described.

All the obsidians from the undisturbed Early Neolithic (Cardial ware phase I) layer of the Su Carroppu rock-shelter (Sardinia island) were studied. Their elemental composition and that of obsidians from the Monte Arci (Sardinia) volcanic complex was determined by ion beam analysis (PIXE). A comparison between the composition of Su Carroppu artefacts, analysed non-destructively, and that of Western Mediterranean analysed in the same conditions shows that the archaeological material belongs to the SA, SB2 and SC Monte Arci-types, to the exclusion of the SB1 type. The typological/technological study of this industry allowed us to reconstruct two chaînes opératoires, for the production of blades (using predominantly SC obsidians) and of flakes (based exclusively on SA and SB2 obsidians), respectively, but on the whole, assemblage blade/bladelet production was performed somewhat preferably with SA and SB2 types. Thus, in the earliest EN culture known on the island, ancient man had, for the making of its obsidian toolkit, a highly adaptive behaviour applied to the reduction of different useful obsidian sources.

International audience; In combination with nuclear microprobes, STIM and PIXE tomography offer non-destructive quantitative three-dimensional characterization of microscopic samples. STIM tomography provides 3D density maps of the analyzed sample with sub-micrometer resolution and PIXE tomography is one of the only methods allowing a quantification of trace elements in three dimensions. These tomography techniques have been developed in several microbeam laboratories around the world since the 80’s. Nevertheless, despite a huge interest in mapping the inner content of a sample without destroying it, the use of ion beam tomography has been limited to a few studies up to now. This comes from the specific requirements of this kind of experiments, i.e. specific experimental set-up (rotation of the sample during analysis) and reconstruction software, making this type of experiments difficult to handle and relatively long. For a few years, efforts have been made to facilitate the implementation of these techniques and reduce the duration of data acquisition: new detectors and new algorithms were proposed. After an introduction to ion beam tomography techniques and to the first developments made in that field, the experimental and data processing specificities of this 3D imaging approach will be discussed. Finally, examples of recent applications to biology and material science are presented, as well as related techniques developed in the field of microbeam 3D imaging.

To investigate the role of increased intra-abdominal pressure (IAP) on the intratumoral accumulation and the antitumor effect of intraperitoneal cisplatin in rats with advanced peritoneal carcinomatosis. To evaluate the tolerance of IAP in pigs, as it is a large animal with a body size equivalent to humans.To investigate if an active convection, driven by a positive IAP, increases cisplatin penetration and antitumor effectiveness in a model of advanced peritoneal carcinomatosis in rats.BDIX rats with macroscopic peritoneal tumors received cisplatin administered as intravenous injection (IV), conventional intraperitoneal injection (IP), or sustained intraperitoneal injection of cisplatin given in a large volume of solvent for maintaining IAP for 1 hour. Platinum tissue concentration was measured by atomic absorption spectroscopy (AAS), and platinum distribution into the tumor nodules was assessed by the particular-induced x-ray emission (PIXE) method. The antitumor effect was assessed in a survival experiment. The hemodynamic, local, and systemic tolerance of IAP, with or without cisplatin, was evaluated in Large White pigs.The maximum tolerated IAP was 22 mm Hg for 1 hour in nonventilated rats. IAP, in comparison with IV or conventional IP injections, resulted in the increased concentration and depth of diffusion of platinum into diaphragm and peritoneal tumor nodules. Consequently, IAP treatment induced an extended survival of rats treated at an advanced stage of carcinomatosis. In 7 50- to 70-kg ventilated pigs, a 40-mm Hg IAP was well tolerated when maintained stable for 2 hours. Renal failure occurred in pigs receiving a total dose of 200 and 400 mg of cisplatin with IAP, but a dose of 100 mg was well tolerated.Intraperitoneal chemotherapy with increased IAP, in comparison with conventional IP or IV chemotherapy, improved the tumor accumulation and the antitumor effect of cisplatin in rats bearing advanced peritoneal carcinomatosis. In preclinical conditions, the tolerance of sustained IAP was manageable in ventilated pigs.

International audience; rf-Magnetron sputtered LiNiVO4 thin film was used as a negative electrode for lithium microbatteries applications. Their film composition and thickness were analyzed by Rutherford backscattering spectroscopy (RBS) and nuclear reaction analysis (NRA) technique by using 4He+, 7Li(p α) 4He reaction respectively. The structure, surface roughness and homogeneity of these films have been investigated by X-ray diffraction (XRD), atomic force microscopy (AFM) and auger electron spectroscopy (AES) techniques. The amount of lithium inserted into the LiNiVO4 films was analyzed by RBS and NRA studies. The results are comparable to those obtained from the electro-analytical technique (galvanostatic method), indicating that ion beam techniques are complementary tools for the analysis of lithium metal oxide thin films.

The use of in vitro reconstructed human epidermis (RHE) by the cosmetic and pharmaceutical industries is increasing because of its similar physiological mechanisms to native human skin. With the advent of ethic laws on animal experimentation, RHE provides an helpful alternative for the test of formulations. The aim of this study is to check that the RHE mineral status is comparable to that of human native skin by investigating the elemental distributions in the epidermis strata. In addition, possible deleterious effects of the transport on the epidermis ionic content were studied by nuclear microscopy.

Titanium-dioxide is a widely used physical photoprotective component of various cosmetic products. However, very few experiments have been carried out on its penetration through the human epidermal barrier and its possible biological effects in vivo and in vitro. In the frame of the NANODERM EU5 project, the penetration of TiO 2 -nanoparticles through the epidermis of human foreskin grafts transplanted into SCID mice was investigated in the Debrecen and Bordeaux nuclear microprobe laboratories using combined IBA techniques. Transmission electron microscope studies of the same samples were also carried out in the DMPFCS laboratory. The skin grafts were treated with a hydrophobic emulsion containing micronised TiO 2 -nanoparticles in occlusion, for different time periods. Quantitative elemental concentrations and distributions have been determined in 14–16 μm thick freeze-dried sections obtained from quick frozen punch biopsies using STIM, PIXE and RBS analytical methods. Using both microscopic methods, we have observed nanoparticles having penetrated into the corneocyte layers of stratum corneum by direct visualisation in TEM and via their chemical fingerprint in PIXE. The human skin xenograft has proved to be a model particularly well adapted to such penetration studies.

Aluminium hydroxide and aluminium phosphate have been widely used as vaccine adjuvants with a good safety record for several decades. The recent observation in human deltoid muscle of macrophage aggregates containing aluminium hydroxide spicules and termed Macrophagic Myofasciitis (MMF) has encouraged research on aluminium salts. This study was conducted in order to further investigate the clearance of aluminium at the vaccine injection site and the features of induced histopathological lesions. Two groups of 12 monkeys were immunised in the quadriceps muscle with Diphtheria-Tetanus vaccines, which were adjuvanted with either aluminium hydroxide or aluminium phosphate. Three, six or twelve months after vaccination, four monkeys from each group were sacrificed and histopathological examination and aluminium assays were performed on quadriceps muscle sections. Histopathological lesions, similar to the MMF described in humans, were observed and were still present 3 months after aluminium phosphate and 12 months after aluminium hydroxide adjuvanted vaccine administration. An increase in aluminium concentration, more marked in the area of the lesions, was also observed at the 3- and 6-month time points. These findings were localised at the injection site and no similar changes were observed in the distal or proximal muscle fragments. We conclude from this study that aluminium adjuvanted vaccines administered by the intramuscular route trigger histopathological changes restricted to the area around the injection site which persist for several months but are not associated with abnormal clinical signs.

Metal–semiconductor–metal detectors have been fabricated based on AlGaN grown on Si by molecular beam epitaxy. Field distribution and collection efficiency were studied with the ion beam induced charge collection method. The results were explained by numerical two-dimensional calculations of the electric field distribution. The calculated field map and charge buildup at the electrodes are used to explain the bias and position dependence of the ion beam induced charge collection. The similarities and differences with the case of optical detection are discussed.

Some transition metals play important regulatory roles in gene expression. The disturbance of their cellular levels could be involved in oncogene expression and tumorigenesis. Nuclear Microprobe Analysis (NMPA) was used to measure cellular trace metal levels (Mn, Fe, Cu, Zn) in two human neuroblastoma cell lines characterized by distinct genotypes. In this paper, a specific protocol established for sample preparation of neuronal cultured cells is described. Trace metal concentrations in SK-N-SH and IGR-N-91 cells exhibiting respectively a single copy, and 60 copies, of the N-myc oncogene are reported. A brief discussion on experiment design for NMPA of trace metal functions in gene expression is also presented.

The epithelial cells of the human amniotic membrane have been extensively studied by electrophysiologists with the aim of elucidating the mechanisms of transmembrane ionic transfers. In order to provide complementary information about this model, nuclear microanalysis was performed using the CENBG ion microbeam. Quantitative mapping of the human amnion was carried out and the distributions of most mono- and divalent ions involved in cellular pathways (Na+, Mg2+, Cl−, Ca2+) were determined. The ionic cellular content was also compared, before and after incubation in a Hanks' physiological fluid and the resultant ions transfers were determined. The aim of this paper is to expose the advances of this experimental model, more particularly after the development of simulation programs which improved the accuracy of PIXE analysis in the measurement of low energy X-rays emitters. Statistically significant results can now be extracted and can be explained taking into account the results of previous electrophysiological experiments.

The effect of taurine on the Na(+), K(+), Cl(-) concentration and distribution in epithelial and compact layers of the human amniotic membrane had been investigated using the Bordeaux nuclear microprobe. Particle induced X-ray emission and Rutherford backscattering spectrometry techniques had been used to provice quantitative measurements. In physiological medium, the monovalent ions concentrations were identical in epithelial and compact layers. The addition of taurine in Hanks' physiological fluid had no effect on Na(+) concentration, but decreased K(+) and Cl(-) concentration in both layers. The quantitative results were related to electrophysiological observations on the effect of taurine on ionic exchanges through channels and paracellular pathways.

International audience; High helium contents will be generated within minor actinide doped uranium dioxide blankets which could be used in fourth generation reactors. In this framework, it is essential to improve our understanding of the type of damage which a pellet could incur as a result of extensive helium build-up. This paper is an attempt at tackling this issue. Sintered uranium dioxide disks have been implanted with helium ions then annealed at various temperatures. Above a concentration of 0.4 at.% and above 1000°C, optical images of the sample surface revealed swollen grains and extensive areas which have exfoliated. Nuclear reaction microanalyses and atomic force microscopy observations were performed to demonstrate that helium has substantially precipitated within the swollen grains. Massive precipitation of the gas leads under these conditions to sample surface blistering which appears to precede flaking. Deuterium ion irradiations have also been performed at ambient and a direct flaking of the sample surface was observed, but for this phenomenon to be observed required much higher doses than in the He study, indicating that temperature could be an essential ingredient for gas to migrate and cause extensive precipitation. Such phenomena could possibly lead to degradation of the fuel.

International audience; ntibody-based micro-arrays instruments are very promising tools for the search for biomarkers in planetary exploration missions. Since such instruments have never been used in this context, it is important to test their resistance to space constraints. In particular, cosmic particles might be deleterious. In the present study, we have investigated the effect of low energy protons (2 MeV) on antibody performances with fluences levels much greater than expected for a typical mission to Mars. We show that these particles do not alter significantly the antibody recognition capability for both free (in solution) and grafted (covalently bound to the support) freeze-dried antibodies. Details of the freeze-dried drying process used to optimize antibody performances during our experiments are also presented.

Fifty-six pieces of obsidian from the Öküzini Cave in SW Anatolia were elementally characterised using particle induced X-ray emission [ PIXE], the artefacts coming from strata that span the early Epi-Palaeolithic to Late Chalcolithic. The obsidian comes from two sources in southern Cappadocia, East Göllü Dağ and Nenezi Dağ (380 km distant), representing the earliest evidence for these sources’ use at distance. The cave’s inhabitants perpetually existed on the margins of those socio-economic networks responsible for the circulation of these central Anatolian resources, obsidian only rarely crossing the cultural boundaries that separated the cave’s populations from their contemporaries in the Konya Plain and Cilicia., La composition élémentaire de 56 pièces en obsidienne de la grotte d’Öküzini (sud-ouest de l’Anatolie), provenant des niveaux épipaléolithiques à chalcolithique, a été caractérisée par sonde nucléaire PIXE. Elle les rattache à deux sources cappadociennes, celles du Göllü Dağ Est et du Nenezi Dağ, distantes de 380 km ; ce serait l’utilisation la plus ancienne jamais observée à une telle distance. Les habitants de la grotte d’Öküzini ont toujours été à la marge des réseaux socio-économiques responsables de la circulation des ressources anatoliennes. Ainsi, l’obsidienne n’a que rarement franchi les limites culturelles qui séparaient les occupants de cette grotte de leurs contemporains dans la plaine de Konya, et de la Cilicie., Carter Tristan, Le Bourdonnec François-Xavier, Kartal Metin, Poupeau Gérard, Calligaro Thomas, Moretto Philippe. Marginal Perspectives: Sourcing Epi-Palaeolithic to Chalcolithic Obsidian from the Öküzini Cave (SW Turkey). In: Paléorient, 2011, vol. 37, n°2. pp. 123-149.

International audience; Abstract Deciphering the molecular basis of toxicology mechanism induced by nanoparticles (NPs) remains an essential challenge. Ion Beam Analysis (IBA) was applied in combination with Transmission Electron Microscopy and Confocal Microscopy to analyze human keratinocytes exposed to TiO(2)-NPs. Investigating chemical elemental distributions using IBA gives rise to a fine quantification of the TiO(2)-NPs uptake within a cell and to the determination of the intracellular chemical modifications after TiO(2)-NPs internalization. In addition, fluorescent dye-modified TiO(2)-NPs have been synthesized to allow their detection, precise quantification and tracking in vitro. The internalization of these TiO(2)-NPs altered the calcium homeostasis and induced a decrease in cell proliferation associated with an early keratinocyte differentiation, without any indication of cell death. Additionally, the relation between the surface chemistry of the TiO(2)-NPs and their in vitro toxicity is clearly established and emphasizes the importance of the calcium homeostasis alteration in response to the presence of TiO(2)-NPs.

International audience; Biochips are promising instruments for the search for organic molecules in planetary environments. Nucleic acid aptamers are powerful affinity receptors known for their high affinity and specificity, and therefore are of great interest for space biochip development. A wide variety of aptamers have already been selected toward targets of astrobiological interest (from amino acids to microorganisms). We present a first study to test the resistance of these receptors to the constraints of the space environment. The emphasis is on the effect of cosmic rays on the molecular recognition properties of DNA aptamers. Experiments on beam-line facilities have been conducted with 2 MeV protons and fluences much higher than expected for a typical mission to Mars. Our results show that this irradiation process did not affect the performances of DNA aptamers as molecular recognition tools.

The micro-PIXE technique has been regularly carried out for more than two years to provide elemental distributions in human cells. Using this technique in the framework of cellular biology, two research axes have been developed: the cellular pharmacology f chemotherapeutic agents and the physiology of ionic cellular exchanges. These studies are based upon in vitro experimental models of human cells, either under the form of isolated cultured cells or as part of well-structured tissues. The aim of this paper is to present the experimental procedures and methodological aspects of cellular and subcellular quantitative mapping. Cell processing, identification of intracellular structures, quantitatives results and beam damage will be discussed and illustrated by examples issuing from the above-mentioned studies.

International audience; In this paper we evaluate the relative analytical capabilities of SEM-EDS, PIXE and EDXRF for characterizing archaeologically significant Anatolian obsidians on the basis of their elemental compositions. The study involves 54 geological samples from various sources, together with an archaeological case study involving 100 artifacts from Neolithic Çatalhöyük (central Anatolia). With each technique the artifacts formed two compositional groups that correlated with the East Göllü Dag and Nenezi Dag sources. The non-destructive capabilities of these methods are emphasized (albeit with certain analytical limitations in the case of SEM-EDS), suggesting important new techniques for Near Eastern obsidian provenance studies.

The Geant4-DNA project proposes to develop an open-source simulation software based and fully included in the general-purpose Geant4 Monte-Carlo simulation toolkit. The main objective of this software is to simulate biological damages induced by ionizing radiations at the cellular and sub-cellular scale. This project was originally initiated by the European Space Agency for the prediction of the deleterious effects of radiations that may affect astronauts during future long duration space exploration missions. In this paper, the Geant4-DNA collaboration presents an overview of the whole on-going project, including its most recent developments that are available in the Geant4 toolkit since December 2009 (release 9.3), as well as an illustration example simulating the direct irradiation of a biological chromatin fiber. Expected extensions involving several research domains, such as particle physics, chemistry and cellular and molecular biology, within a fully interdisciplinary activity of the Geant4 collaboration are also discussed.

Cobalt is known to be toxic at high concentration, to induce contact dermatosis, and occupational radiation skin damage because of its use in nuclear industry. We investigated the intracellular distribution of cobalt in HaCaT human keratinocytes as a model of skin cells, and its interaction with endogenous trace elements. Direct micro-chemical imaging based on ion beam techniques was applied to determine the quantitative distribution of cobalt in HaCaT cells. In addition, synchrotron radiation X-ray fluorescence microanalysis in tomography mode was performed, for the first time on a single cell, to determine the 3D intracellular distribution of cobalt. Results obtained with these micro-chemical techniques were compared to a more classical method based on cellular fractionation followed by inductively coupled plasma atomic emission spectrometry (ICP-AES) measurements. Cobalt was found to accumulate in the cell nucleus and in perinuclear structures indicating the possible direct interaction with genomic DNA, and nuclear proteins. The perinuclear accumulation in the cytosol suggests that cobalt could be stored in the endoplasmic reticulum or the Golgi apparatus. The multi-elemental analysis revealed that cobalt exposure significantly decreased magnesium and zinc content, with a likely competition of cobalt for magnesium and zinc binding sites in proteins. Overall, these data suggest a multiform toxicity of cobalt related to interactions with genomic DNA and nuclear proteins, and to the alteration of zinc and magnesium homeostasis.

International audience; Detecting life in the Solar System is one of the great challenges of new upcoming space missions. Biochips have been proposed as a way to detect organic matter on extraterrestrial objects. A biochip is a miniaturized device composed of biologically sensitive systems, such as antibodies, which are immobilized on a slide. In the case of in situ measurements, the main concern is to ensure the survival of the antibodies under space radiation. Our recent computing simulation of cosmic ray interactions with the martian environment shows that neutrons are one of the dominant species at soil level. Therefore, we have chosen, in a first approach, to study antibody resistance to neutrons by performing irradiation experiments at the Applications Interdisciplinaires des Faisceaux d'Ions en Region Aquitaine (AIFIRA) platform, a French ion beam facility at the Centre d'Etudes Nucleaires de Bordeaux-Gradignan in Bordeaux. Antibodies and fluorescent dyes, freeze-dried and in buffer solution, were irradiated with 0.6 MeV and 6 MeV neutrons. Sample analyses demonstrated that, in the conditions tested, antibody recognition capability and fluorescence dye intensity are not affected by the neutrons.

Technologic analyses of Neolithic obsidian assemblages are quite rare in Sardinia, like in the wider Western Mediterranean. Such an approach is presented here in conjunction with a visual/instrumental provenance study for the Rio Saboccu Early Neolithic (EN) site, which yielded more than 1000 obsidian artefacts. It is shown that this mostly expedient industry was realized from a non-opportunistic exploitation of the four obsidian types of the nearby Monte Arci (Sardinia) volcanic massif. The choice of the raw materials was chiefly guided by their intrinsic knapping qualities and in function of the maximum size of the expected final products; hence some selection in the (primary and/or secondary) sources exploited. The obsidian industries of EN sites from the northern Tyrrhenian area present clearly some affinities with that of Rio Saboccu and of other EN Sardinian sites, mainly those located in its vicinity. This suggests a regional influence of the EN communities settled in the proximity of the Monte Arci.; Très peu d’analyses technologiques ont été effectuées sur des assemblages d’obsidiennes du Néolithique ancien sarde et, plus généralement, de Méditerranée occidentale. Une telle approche est présentée ici, en association avec une étude visuelle/instrumentale de provenance, pour le site Néolithique ancien de Rio Saboccu (Sardaigne), où plus de 1000 artefacts ont été collectés. Il est montré que cette industrie, pour l’ensemble peu investie, a été réalisée à partir d’une exploitation non opportuniste des quatre types d’obsidiennes du massif volcanique voisin du Monte Arci. Le choix de la matière première a principalement été guidé par la dimension des produits finaux espérés et les aptitudes à la taille, d’où la détermination de lieux d’exploitation spécifiques (sources primaires et/ou secondaires). Les industries en obsidienne des sites du Néolithique ancien de la zone Nord-Tyrrhénienne présentent des affinités certaines avec celles de Rio Saboccu et d’autres sites voisins. Il semblerait donc que les communautés proches du Monte Arci aient pu, à cette époque, exercer une certaine influence régionale.

Nuclear microscopy is a technique based on a focused beam of accelerated particles that has the ability of imaging the morphology of the tissue in vivo and of producing the corre- spondent elemental maps, whether in major, minor, or trace concentrations. These characteristics constitute a strong advantage in studying the morphology of human skin, its elemental distribu- tions and the permeation mechanisms of chemical compounds. In this study, nuclear microscopy techniques such as scanning transmission ion microscopy and particle induced X-ray emission were applied simultaneously, to cryopreserved human skin samples with the purpose of obtaining high-resolution images of cells and tissue morphology. In addition, quantitative elemental profiling and mapping of phosphorus, calcium, chlorine, and potassium in skin cross-sections were obtained. This procedure accurately distinguishes the epidermal strata and dermis by overlapping in real time the elemental information with density images obtained from the transmitted beam. A valida- tion procedure for elemental distributions in human skin based on differential density of epidermal strata and dermis was established. As demonstrated, this procedure can be used in future studies as a tool for the in vivo examination of trans-epidermal and -dermal delivery of products. Microsc.

We report on the visualization of the penetration of sunscreen formulations containing TiO2 nanoparticles (about 20 nm primary particle size) into hair follicles of both human and porcine skin using the complementary methods of ion microscopy (PIXE, RBS, STIM) and autoradiography. Particles were found as deep as approx. 400 pin in the follicle, obviously introduced mechanically rather than by a diffusive process. No particles were observed in vital tissue nor in sebaceous glands. (c) 2007 Elsevier B.V. All rights reserved.

It is proposed in this study to observe the influence of P2O5 on the formation of the apatite-like layer in a bioactive glass via a complete PIXE characterization. A glass in the SiO2-CaO-P2O5 ternary system was elaborated by sol-gel processing. Glass samples were soaked in biological fluids for periods up to 10 days. The surface changes were characterized using Particle Induced X-ray Emission (PIXE) associated to Rutherford Backscattering Spectroscopy (RBS), which are efficient methods for multielemental analysis. Elemental maps of major and trace elements were obtained at a micrometer scale and revealed the bone bonding ability of the material. The formation of a calcium phosphate-rich layer containing magnesium occurs after a few days of interaction. We demonstrate that the presence of phosphorus in the material has an impact on the development and the formation rate of the bone-like apatite layer. Indeed, the Ca/P atomic ratio at the glass/biological fluids interface is closer to the nominal value of pure apatite compared to P2O5 free glasses. It would permit, in vivo, an improved chemical bond between the biomaterials and bone., Comment: presented at CAARI 2006:19th International Conference on the Application of Accelerators in Research and Industry, Forth Worth, Etats Unis, 20-25 Aug 2006, 11 pp, 4 figures, submitted to NIMB

This study presents the simulation of ionizing track structures in single biological cells modeled as high resolution cellular phantoms using the new "GEANT4 DNA" very low energy extension of the GEANT4 Monte Carlo simulation toolkit.

Bioactive glasses possess the ability to bond to living tissues through the formation of a calcium phosphate-rich layer at their interface with living tissues. This paper reports the different steps of this bioactivity process via a complete micro-PIXE characterization of a sol-gel derived SiO2-CaO bioactive glass in contact with biological fluids for different delays. Multi-elemental cartography at the glass/biological fluids interface together with major and trace elements quantification permit a better understanding of the five reaction stages involved in the bioactivity mechanisms. The presence of phosphorus was detected at the periphery of the material within 6 h of interaction with biological fluids. A calcium phosphate-rich layer containing magnesium is formed after a few days of interaction and presence of bone-like apatite is deduced from the calculation of the Ca/P ratio at the material interface. That is of deep interest for clinical applications, because this biologically active behavior results in the formation of a strong interfacial bond between the glass and host tissues, and will stimulate bone-cell proliferation.

AVIRM, présenté par Z. Francis, soumis aux proceedings; International audience; A set of processes specialized for the simulation of particle interactions with water has been developed in the Geant4 Low Energy Electromagnetic package. The models cover the interactions of electrons, protons and light ions down to the electronVolt energy scale. They address a physics domain relevant to the simulation of radiation effects in biological systems, where water represents an important component. The software design, the physics models implemented and an overview of their tests are described.

Implants used as biomaterials have to fulfill conditions of functionality, compatibility and sometimes bioactivity. There are four main families of biomaterials: metals and metal alloys, polymers, bioceramics and natural materials. Because of corrosion and friction in the human body, implants generate debris. This debris may develop toxicity, inflammation and prosthetic unsealing by osseous dissolution. Nature, size, morphology and amount of debris are the parameters influencing the tissue responses. In this paper, we characterised metallic contamination produced by knee prosthesis, composed with TiAl6V4 or Co–Cr–Mo alloys, into surrounding capsular tissue by depth migration, in vivo behaviour, content, size and nature of debris by PIXE (Particle Induced X-ray Emission) method associated with RBS (Rutherford Backscattering Spectroscopy). Debris distribution in the whole articulation is very heterogeneous. Debris migrates several thousand micrometers in tissues, with a characteristic decrease. Solid metallic particles of about micrometer size are found in the most polluted samples, in both alloys TiAl6V4 and Cr–Co–Mo. In the mean volume analysed by PIXE, the concentration mass ratios [Ti]/[V] and [Co]/[Cr] confirm the chemical stability of TiAl6V4 debris and show the chemical evolution of Cr–Co–Mo debris. Development of a protocol to prepare thin targets permits us to correlate PIXE and histological analysis in the same zone. The fibrous tissue (collagen fibres, fibroblasts) and macrophage cells are observed with optical microscope in polluted areas. This protocol could locate other pathologies in ppm contamination range, thanks to the great sensitivity of the PIXE method.