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Wolves were exterminated in France in the late 19th and early 20th centuries. Therefore, livestock breeders and herders were unprepared when wolves arrived from Italy in 1993, the year after France committed to the European Union (EU) to protect wolves. Today, ~580 wolves, whose numbers are growing exponentially, are present in over one-third of France. During the last 10 years, livestock deaths from wolves have grown linearly from 3215 in 2009 to 12451 in 2019, despite France implementing extensive damage protection measures since 2004, including reinforced human presence, livestock guard dogs, secured pasture fencing and electrified night pens. The failure to prevent damage is clear. Wolves enter mosaic landscapes where grazing livestock are abundant and easy prey. Wolves are intelligent and opportunistic. As a strictly protected species, it seems they no longer associate livestock with humans and humans with danger. Half of the successful attacks now occur during the day, notwithstanding the presence of dogs and humans. Considering the high costs of unsatisfactory protection, France recently modified its wolf management policy. In addition to non-lethal means of protection, breeders that have suffered several attacks by wolves are now permitted, by derogation to the law, to defensively shoot wolves. Based upon evidence from other countries, we suggest re-establishing a reciprocal relationship with wolves. Breeders and herders should be allowed to shoot wolves to defend their herds against wolf attacks, not after several successful predation events. Defence shooting would also upgrade the efficiency of non-lethal means, as warning signals for wolves to respect. Rather than passive coexistence, we need to embrace a dynamic and ever-evolving process of coadaptation between humans and wolves, relying on the adaptive capacities of both.

Global simulations of the atmospheric dispersion of worldwide industrial Xe‐133 releases have revealed a large spatial and day‐to‐day variability of the resulting so‐called Xe‐133 atmospheric background. Most stations of the International Monitoring System (IMS) of the Comprehensive nuclear‐Test‐Ban Treaty Organization actually detect Xe‐133 regularly. Measured levels are explained by a varying combination of local and distant industrial sources and can interfere with discrimination of nuclear test signatures. Therefore, a better understanding of the Xe‐133 atmospheric background is needed. In this study, a validated 2 year simulation data set and a 4 year measurement data set of Xe‐133 activity concentrations have been analyzed in order to characterize possible seasonal variations of the Xe‐133 atmospheric background due to atmospheric circulation, with a focus on (i) global distributions, (ii) occurrences of detections by the IMS network, and (iii) time series of monthly averages at IMS stations. Results show a larger spatial extent of the atmospheric background during winter months, which translates into a larger number of detections on the IMS network during winter months for both hemispheres. Some IMS stations present a significant seasonal variability in terms of levels, or both in terms of levels and origins. However, not all IMS stations are subject to seasonal variations, given their location with respect to sources and large‐scale atmospheric circulation. In addition, a first set of predicted information about expected levels of atmospheric background at IMS stations not yet operational is provided, given the current knowledge of sources. Characterization of the seasonal variability of Xe‐133 levels at monitoring stations worldwide from global scale simulations and measurementsHighlighting of increased occurrence of Xe‐133 atmospheric background detections in winter due to seasonal effects for both hemispheresHighlighting of seasonal changes of industrial contributors to the Xe‐133 levels simulated at monitoring stations

In Mediterranean regions, traditional pastoral systems involve shepherds leading flocks along daily grazing circuits on arid rangelands. Over the past decades, these systems have become increasingly agro-pastoral and the importance given to feeding flocks on rangelands is variable. Our study aimed at investigating the local ecological knowledge (LEK) about forage plants and animal foraging behaviour of shepherds in a pastoral area of Morocco, and eventually analysing the possible interactions between such LEK, its utilisation for grazing management and the pastoral status of the farm. Eleven semi-directive interviews with shepherds, either salaried or owning their own farm, were carried out at three sites differing in terms of agricultural context and available forage resources. Shepherds’ LEK included recognising and naming forage plants and rangeland types, identifying preferred or less preferred plants or plant parts, describing circumstantial palatability of plants depending mainly on season, other locally available plants and watering times. LEK about animal feeding preferences and its integration into grazing management was more extensive at sites where pastoral systems were still most valued, and for shepherds who were either experienced or who were considering the activity in the future. Conversely, young salaried shepherds or farmer-shepherds who devoted more attention to the agricultural component of their system seemed to be less knowledgeable about the subject. In a context where pastoralism is challenged both by the higher profitability of agriculture and by the depletion of pastoral resources as a result of frequent droughts and decreased surface area devoted to grazing lands, the future of such LEK is uncertain. The perpetuation of LEK might depend on the ability of local extension services to value farmers’ LEK and to help them enrich it with scientific knowledge.

Une dermo-hypodermite inflammatoire au décours d’un traumatisme direct évoque en premier lieu une infection. Deux diagnostics différentiels sont importants : le syndrome de Morel-Lavallée et la cytostéatonécrose.

A detailed report on the X-ray Magnetic Circular Dichroism (XMCD) investigation of monolayers of Mn12-based single molecule magnets (SMMs) deposited on gold Au(111) is presented. A semi-quantitative analysis of data is provided in order to extract chemical and magnetic information on Mn ions, by comparison with XMCD on bulk samples. This work points that XMCD is a key-tool for the characterization of SMMs-based nanostructured systems. XMCD surface sensitivity and element-specificity will play a fundamental role in the identification of good candidates for SMMs based devices.

Time Resolved Laser-Induced Spectrofluorometry (TRLIS) is a very sensitive and selective method that has been used for actinides and lanthanides analysis in the nuclear fuel cycle. This technique has been used in different fields such as in geology, in the Purex process, in the environment, in the medical and in waste storage assessment. Spectroscopic data (λ excitation, λ emission, lifetime), limits of detection and results obtained in previously quoted fields are presented.

This paper is concerning issues regarding the semantic indexing of resources in a peerto- peer network. An important requirement is a good quality of the discovery (i.e. the selection of results very related to a specific request) and a short response time. Keys used for indexing and the corresponding URLs of indexed resources are stored in a Distributed Hash Table (DHT) scattered among the different peers of a community. A key of indexing is a semantic description of resources and refers to elements belonging to ontologies of domain and to knowledge bases. We propose a model of indexing patterns in order to generate keys. It is used to guide users for producing assertions about their resources. It induces navigation inside ontologies presented in graphical user interfaces in a friendly and easy to use way. With different examples, we present the main cases of key generation that define the indexing context of a resource. We also describe experiments performed in test environments simulating various situations.

Human memory can be split into familiarity and recollection processes which contribute to different aspects of memory function. These separate processes result in different experiential states. In this review, we examine how this dominant theoretical framework can explain the subjective experience of people with Alzheimers disease, the profile of their memory impairments and their inability to reflect on their performance metacognitively. We conclude with a brief overview of the brain regions supporting conscious experience of memory, and propose that the memory and awareness deficits seen in Alzheimers disease could be conceived of as a deficit in autonoetic consciousness. A future priority for research is to take these robust constructs into research programmes examining rehabilitation and pharmacological intervention.

Environmental context. Oceans represent 70% of the blue planet, and surprisingly, ocean emission in term of volatile organic compounds is poorly understood. The potential climate impacts on a global scale of various trace organic gases have been established, and the terrestrial inputs are well studied, but little is known about which of these can be emitted from oceanic sources. In the present study, atmospheric samples were taken over the Southern Indian Ocean, while crossing some oceanic fronts and different phytoplankton species. Such a study should aid in understanding oceanic emission, especially from phytoplankton, and will help modellers to determine concentrations of organic traces in the remote marine troposphere.Abstract. Considering its size and potential importance, the ocean is poorly characterised in terms of volatile organic compounds (VOC) that play important roles in global atmospheric chemistry. In order to better understand their potential sources and sinks over the Southern Indian Austral Ocean, shipborne measurements of selected species were made during the MANCHOT campaign during December 2004, on board the research vessel Marion Dufresne. Along the transect La Réunion to Kerguelen Island, air measurements of selected VOC (including dimethylsulfide (DMS) isoprene, carbonyls and organohalogens), carbon monoxide and ozone were performed, crossing subtropical, temperate and sub-Antarctic waters as well as pronounced subtropical and sub-Antarctic oceanic fronts. The remote marine boundary layer was characterised at latitudes 45–50°S. Oceanic fronts were associated with enhanced chlorophyll and biological activity in the seawater and elevated DMS and organohalogens in the atmosphere. These were compared with a satellite-derived phytoplankton distribution (PHYSAT). Diurnal variation for isoprene, terpenes, acetone and acetaldehyde was observed, analogously to recent results observed in mesocosm experiments.

Radionuclides can occur in the environment either through chronic releases of nuclear facilities, or due to incidents or accidents. In order to study there behaviors in the environment (migration, retention, transfer, ...) and in human organisms (metabolism, retention, excretion), it is of prime importance to know their solution chemistry, and more particularly thermodynamic equilibrium constants, allowing to calculate their speciation. In fact, speciation governs the migration, the bioavailability and the toxicity of elements. Moreover, this knowledge is also of great interest for decorporation or decontamination purposes. In this framework, a CEA working group on speciation has been created in order to share data both on thermodynamic constants and on analytical speciation methods, interesting chemists, environmentalists and biologists. It has been focused, in a first time, on actinides and a choice of specific ligands considered to be most representative of environmental and biological media. The thermodynamic database used is BASSIST (developed by CEA) in interaction with the speciation model JCHESS. Different examples are then presented on the selection of data (thermodynamic constants, ligands of interest) through benchmark exercises to test our state of knowledge in this area. Also, analytical methods to determine thermodynamic constants or direct speciation are discussed.

A new procedure for the determination of uranium by packed-column supercritical chromatography is proposed here. 1-Phenyl-3-methyl-4-benzoylpyrazolin-5-one (HPMBP) is chosen, as it can easily extract uranium from a nitric acid aqueous phase in the presence of a synergistic agent. Eighteen columns packed with C18-grafted silica have been tested. Adding the chelating agent directly to the mobile phase greatly improves the elution peak shapes. Trioctylphophine oxide (TOPO), diphenyl sulfoxide, and phenanthrene have been studied as synergistic agents. The influence of the injection solvent is also shown, and a calibration curve is obtained for uranium in the range of 20 ng to 2 μg injected. The limit of detection is 2 μg of uranium. The accuracy of the method is 4%, and the repeatability measured (1σ) is 3%.

Liquid-liquid extraction of zirconium, one of the most important fission products, was followed using electrospray ionization mass spectrometry under conditions simulating reprocessing of nuclear spent fuel. Zr^IV can precipitate from the organic phase after extraction by dibutylphosphoric acid (HDBP), the most common degradation product of tributylphosphate (TBP) radiolysis. Different complexes were detected with electrospray used in positive or negative ion modes, according to the extraction conditions such as the ligand/metal ratio. Stoichiometry of the Zr^IV complexes was determined by combining isotopic labeling [H¹⁵NO3] of the aqueous phase in the extraction system and tandem mass spectrometry experiments. These results were compared with the species observed using other techniques reported in the literature. The mechanisms of ionization/desorption of these complexes are proposed depending on the organic ligand character (neutral (L) such as TBP, or acidic (HL') such as HDBP), and the ionization mode used. Copyright © 2000 John Wiley & Sons, Ltd.

This paper discusses the development of a two-dimensional finite element coupled hydraulic–sediment transport scheme for application to lowland floodplain environments. Recent developments in numerical algorithms have led to the development of two- and three-dimensional hydraulic models which are capable of simulating open channel and floodplain hydraulics at river reach scales of 1–60 km. However, these hydraulics schemes have not been linked with suitable sediment dynamics schemes. This paper describes the numerical developments necessary to extend an existing two-dimensional finite element solution of coupled hydraulic and sediment transport to fluvial floodplains. These include correct choice of numerical solvers to prevent artificial build-up of tracer mass in dry areas, control of artificial diffusion and implementation of an equation base appropriate to moving-boundary problems. Four experiments of increasing complexity were undertaken in order to ascertain the predictive ability of the model to produce realistic simulations of floodplain sediment deposition. Results showed that a two-dimensional-depth averaged flow field representation captures much of the gross behaviour of suspended sediment transport for reach scale fluvial applications.

Speciation of actinides, lanthanides, and fission products is a major challenge in the framework of nuclear fuel cycle studies. Electrospray–mass spectrometry has been used for uranium speciation. Free uranyl (UO22+), the first hydroxo complex (UO2OH+), and the oligomeric species (UO2)3(OH)5+have been observed as a function of pH. Different aqueous solvents (sodium perchlorate, perchloric acid/ammonium acetate, and perchloric acid/ammonia) were tested in order to limit the presence of adducts. The influence of various parameters such as the cone voltage, temperature, and gas flow rate is presented. Comparison with results obtained by time-resolved laser-induced fluorescence on the same solutions shows a similar tendency despite a slight shift in pH relative to the OECD database.

Les époxydes hydrolases (EHs) régulent l’homéostasie cellulaire par l’hydrolyse de substrats époxydes en diols moins réactifs. La première EH découverte a été EPHX1. Les fonctions des EHs restent en partie inconnues et aucun variant pathogène n’a été rapporté chez l’homme à ce jour.

Laser-induced breakdown spectroscopy (LIBS), a spectrochemical technique in which a laser beam is used as the excitation source, was applied to detect trace elements contained in uranium and plutonium dioxides. Partial spectra of plasmas, generated by focusing the second harmonic (Λ = 532 nm) of a pulsed Nd:YAG laser on UO2and PuO2targets at atmospheric pressure, were recorded. Eighteen impurities at concentrations of about 500 ppm (μg/g) and twelve at concentrations of about 100 ppm, respectively, were observed in the rich emission matrices UO2and PuO2. The possibility of quantifying impurities in such matrices is discussed.

A new method of preparing solid state chlorometallates by reductive dechlorination of solvated niobium pentachloride with the vapour of nominally free atoms of erbium and samarium is described. Products were prepared in a model of a rotatable Pyrex cryostat by evaporating Sm or Er into a turbulently mixed solution of NbCl5in toluene at 130 K. Since no single crystal had been isolated, local order around the Nb atom was probed by far-IR, XPS, and EXAFS spectroscopy. Depending on the vaporized rare earth, two structurally distinct products were found. Combining information gathered by EXAFS results and ab initio EXAFS calculations on clusters to model the growing solid state compound using the FEFF6 code, two different condensation patterns were proposed: chlorine edge-shared aggregation was preferred for Er vaporization, face-shared condensation patterns emerged from Sm vaporization.Key words: X-ray absorption spectroscopy, niobium, metal vapour synthesis, XPS.

To detail the respective role of geotaxis, phototaxis and photokinesis variations in the control of distribution and vertical migrations of sole larvae and juveniles during development, sets of experiments were carried out in 3 types of vertical tanks: cylindrical tank illuminated from the surface, cylindrical tank illuminated from below, U shape tank illuminated from one surface. Automatic detection with infrared barriers was used to record vertical movements.Under irradiances of diurnal levels, geopositivity maintained newly hatched larvae and metamorphosed animals near the bottom, despite their permanent photopositivity; old larvae exhibited a geonegative behaviour and swam in the whole water column, regardless the light orientation. During light - darkness changes or under day - night alternances, upwards movements occured at irradiances lower than a threshold value, characteristic of each developmental stage (5.10-2 μW. cm-2 in larvae, from 10-3 to 10-4 μW. cm-2 in young juvenile). These upward movements were controlled respectively in young larvae by the reverse of geotaxis and a negative photoorthokinesis, in old larvae by an increase of photopositivity at irradiances of crepuscular and nocturnal levels, and in juvenile by both geotaxis reversal and photopositivity below the threshold of this geotaxis reversal. This control was clearly demonstrated by a nocturnal unilateral accumulation at the illuminated surface in U shape tank experiment.These experimental results suggest hypotheses concerning the specific role of light in the control of vertical migrations.

To determine the role of geotaxis in the control of the distribution and the vertical migration of sole larvae and juveniles during development, sets of experiments using visual observations with an IR converter in total darkness were carried out in transparent vertical tank, horizontal white light beam coming through the tank. Observations clearly demonstrate geotactic reactions and geotaxis changes during development. Under artificial light intensities of diurnal values, between 1000 and 10 μw. cm-1, the very young larvae (stage I) exhibit geopositive reactions; then, from about four days post hatching to metamorphosis, the number of geonegative reactions increases progressively. At and after metamorphosis, sole only exhibit geonegative reactions at artificial irradiances corresponding to nocturnal values (below 1 μw. cm-2). The possible effects of geotaxis in each developmental stage, are discussed with respect of photokinesis changes during ontogenesis.

En Mediterranee, dans l'intervalle de 10 a 25°C, les rythmes endogenes d'emergence des Peracarides fouisseurs Urothoe elegans et Eurydice inermis peuvent etre affectes par la temperature.La periode n'est que peu modifiee. A 24°C, elle est de 24 heures environ chez les deux especes; a 12°C, elle atteint 24 heures 10 minutes chez l'Amphipode, 24 heures 20 minutes chez l'Isopode.Lors des variations thermiques, on observe quelques changements de phase, mais de faible amplitude seulement. Leur importance s'accroit en dessous de 13°C.Les emergences sont plus intensement affectes. Dans l'intervalle de 13 a 24°C, leur nombre augmente avec la temperature; entre 13 et 10°C, en dessous d'un certain seuil critique, qui semble varier selon l'etat physiologique des animaux, l'enfouissement peut devenir presque permanent.Contrairement a leur abondance, la dispersion des emergences au cours de la journee tend a augmenter quand la temperature decroit. Entre 10 et 13°C, on constate aussi l'existence d'un seuil critique: le rythme peut s'annuler brutalement.Les consequences possibles de la variation de ces rythmes sur les modifications de la densite des especes dans le plancton nocturne sont envisagees.In the Mediterranean sea, the endogenous daily rhythm of emergence of the burrowing Peracarida Urothoe elegans and Eurydice inermis can be affected by the temperature changes between 10 and 25°C.The “free-running period” is only slightly affected. In both species, the period is of about 24 hours at 24°C; at 12°C, it reaches 24 hours 20 minutes in E. inermis, 24 hours 10 minutes in U. elegans.The changes of phase (advance or delay) take place essentially below 13°C and are never very important.The number of the emergence is more particularly affected. Between 13 and 24°C, it increases with the temperature; between 13 and 10°C, below a critical threshold, it may almost completely disappear.Contrary to their abundance, the dispersion of the swimming activity tends to increase when the temperature falls. Between 10 and 13°C, a critical threshold is also observed: below this level the rhythm may vanish.The possible consequence of the changes of these rhythms upon the density variations of the species in the nocturnal plankton is discussed.

The swimming activity of five burrowing species has been studied in continuous darkness in actographs using photoconductive cells. In each experiment a clear circadian rhythm of nocturnal frequency appears. This rhythm always remained clear during the experiments (more than 30 days for Urothoe elegans and Eurydice inermis).During the first days of the experiments, the swimming activity begins at the same time as the vertical migration of the species in the sea. Afterwards one observes, in amphipods, a drift of the hours of maximum activity toward the morning, whereas isopods only exhibit an extension of these hours.The possible origin of the irregularities of the behaviour of these species in the sea in the direct influence of the physicochemical factors on the rhythms is discussed.Les variations rythmiques de l'activite natatoire de cinq especes fouisseuses ont ete etudiees en presence de sediment et en obscurite continue dans des actographes a barrages photoelectriques. Dans toutes les experiences un rythme net d'activite natatoire de frequence nocturne s'est manifeste, et cela durant toute la duree des experiences (plus de 30 jours chez Urothoe elegans et Eurydice inermis); nous n'avons jamais observe de maintien permanent des organismes dans le sediment. L'activite natatoire commence, durant les premiers jours, a l'heure de la migration verticale de l'espece en mer; on observe ensuite, chez les amphipodes, un decalage progressif des heures d'activite par augmentation de la periode du rythme et, chez les isopodes, un etalement dans le temps des heures d'activite.La grande persistance de ces rythmes dans l'obscurite, la permanence de leur manifestation chez les organismes n'ayant pas subi de stress, conduisent a leur attribuer un caractere plus ou moins autonome. On peut ainsi etre amene a rechercher dans leur sensibilite aux perturbations de tous ordres (stress, variations physico-chimiques), l'origine possible des irregularites de comportement des especes observees dans la nature.

The successive operational Meteosat solar (VIS) sensors have shown significant variations of their spectral band which affected their relative sensitivities to the light scattering by aerosols, molecules and Earth surface. This paper provides a calibration of the various Meteosat VIS sensors used between June 1983, the beginning of data archiving for the International Satellite Cloud Climatology Project (ISCCP), and December 1994, taking into account the characteristics of their individual spectral band thanks to an atmospheric radiative transfer model. The method is based on a monitoring of the reflectance of desert and ocean targets free of clouds and aerosols, and relies on the absolute vicarious calibration of Meteosat-2 performed in late 1981. We find different sensitivities and temporal evolutions for Meteosat-2, -3, -4, and -5, and our results compare well with other more limited calibration studies

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Les techniques de spectroscopie laser sont de plus en plus employées pour l'analyse élémentaire à bas niveau et la spéciation des actinides et autres radionucléides d'intérêt. A partir d'une recherche bibliographique et des expériences développées au sein du Laboratoire de spectroscopie laser analytique, le principe, les performances, les applications ainsi que les avantages et les inconvénients de ces différentes techniques laser sont présentés, une comparaison est effectuée avec une autre technique (non-laser) analytique performante, la torche à plasma – spectrométrie de masse. Les différentes techniques laser présentées sont en spectroscopie moléculaire : la lentille thermique, la spectrofluorimétrie laser à résolution temporelle, la fluorescence induite par laser de l'iode, et en spectroscopie atomique : la spectroscopie optogalvanique, la fluorescence induite par laser en four de graphite, la fluorescence induite par laser dans une torche à plasma, la spectroscopie d'ionisation résonnante colinéaire et l'ionisation laser couplée à la spectrométrie de masse. Les principaux avantages des techniques de spectroscopie laser sont l'absence de préparation d'échantillon, la rapidité, la sélectivité, la sensibilité ainsi que la possibilité de pouvoir effectuer des analyses à distance via fibre optique.

La connaissance du devenir chimique de l'uranium en milieu biologique réclame des études plus approfondies pour comprendre le comportement de l'uranium dans l'organisme. La caractérisation des différentes formes complexées de l'ion uranyle peut être améliorée en combinant deux techniques : la Spectrofluorimétrie Laser à Résolution Temporelle (SLRT) et l'Electrophorèse Capillaire (EC). En effet, l'EC, adoptant le mode de Focalisation IsoElectrique (CIEF), permet la séparation des complexes suivant leurs points Isoélectriques (pI) tandis que la SLRT est une méthode de spéciation à bas niveau qui rend possible l'identification des complexes de l'ion uranyle au moyen de la résolution temporelle et de la déconvolution spectrale. Les résultats qui concernent aussi bien les systèmes inorganiques (phosphate, bicarbonate) que les systèmes biologiques (citrate, transférine) sont présentés et discutés. La complexation uranium - transférine est mise en évidence par l'utilisation de l'EC en mode CIEF.

Abstract: The study of the chemical behavior of uranium in biological medium is still of great interest. By the use of capillary electrophoresis (CE) and time-resolved laser-induced fluorescence (TRLIF), it is possible to characterize the different complexes of uranium. Hence, CE, using the isoelectric focusing mode (CIEF), allows for the separation of the different complexes as a function of their isoelectric points (pI) and TRLIF as a speciation method leads to the identification at very low level of different uranyl complexes by temporal resolution and spectral deconvolution. Results obtained on various inorganic chemical systems (phosphate, bicarbonate) together with biological systems (citrate, transferrin) will be presented and discussed. The complexation between uranium and human transferrin has been pointed out through CIEF.

Abstract: Time-resolved laser-induced fluorescence (TRLIF) is a method of choice for actinides and lanthanides determination at low level in nuclear, biological and environmental samples. This technique is based on pulsed laser excitation followed by temporal resolution of the fluorescence signal. This technique has many advantages such as: high sensitivity, rapidity, triple selectivity and is applicable in a wide range of activity concentrations. TRLIF has been used in several fields such as; geology, in the PUREX process, in the medical field, in the environments and for nuclear waste disposal applications. Trends are towards the use of TRLIF for remote determination via fiber optics and optode as well a speciation.