Negative Concord in Russian. An Overview

In this article I will describe the general properties of Negative Concord in Russian, which is a strict Negative Concord language, where all negative indefinites must co-occur with sentential negation. However, there are several cases where the negation marker can be absent (like in fragment answers) or can appear in a non-standard position (like at the left of an embedded infinitival). I will take into consideration all these specific cases described by the literature on the negation system of Russian and analyse them according to current approaches to Negative Concord

Analyse des hydrocarbures dans des sédiments superficiels de zones côtières Méditerranéennes (Golfe de Fos, Rade de Marseille et Massif des Calanques)

La première partie de ce travail concerne l'origine, la nature et la distribution des hydrocarbures présents dans les sédiments superficiels côtiers entre le delta du Rhône et le port de Cassis. Les teneurs en hydrocarbures totaux sont comprises entre 10 mg.kg-1 à 260 mg.kg-1 séd. sec. Seule la station 21 (émissaire de Cortiou) a un taux d'hydrocarbures très élevé (1067 mg.kg-1 séd. sec) comparativement aux autres stations.Nous avons montré que les hydrocarbures présents dans les sédiments avaient des origines multiples : biogène (apports terrestres et organismes marins) pétrolière (rejets pétroliers), hydrocarbures saturés et pyrolytique (résidus de combustion naturelle ou de combustion pétrolière).La deuxième partie traite d'une expérimentation de contamination artificielle en condition in situ par 20 m de profondeur dans le Golfe de Fos. Nous avons étudié l'évolution des hydrocarbures au bout de 1220 jours sur le site « HycarFos » à l'aide de carottiers fortement contaminés par du BAL 250 (20 g.kg-1 séd. humide).Les principaux résultats de cette étude montrent une disparition importante des hydrocarbures saturés au bout de 1220 jours avec une disparition préférentielle des n-alcanes par rapport aux alcanes ramifiés. Cette évolution est très nette dans les sédiments de surface (0-4 cm) mais également, à un degré moindre, dans les sédiments plus profonds (8-10 cm). Nos résultats sont en parfait accord avec ceux relatifs à l'évolution des hydrocarbures déversés massivement après un naufrage tel que celui de l'Amoco-Cadiz en 1978 sur les côtes bretonnes ou celui de l'Exxon Valdez en1989 sur les côtes d'Alaska.The first part of this work concerns the origin, the nature and the distribution of hydrocarbons present in the coastal surface sediments located between the delta of the Rhone and Cassis harbor. Total hydrocarbons levels ranged from 10 mg.kg-1 to 260 mg.kg-1 sed dry weight. Only station 21 (Cortiou outfall sewer) has a very high hydrocarbon content (1067 dry mg.kg-1 sed. dry weight) compared to the other stations. Origins of hydrocarbons in surficial sediments are multiple : biogenic (terrestrial inputs, marine organisms), anthropogenic (petroleum contamination) and pyrolytic (residues of natural or anthropogenic combustions) The second part of the work deals with a study of the fate of oil in infralittoral coastal sediments. A field experimentation of artificial contamination has been conducted by 20 m of depth. We studied the evolution of hydrocarbons during a 1220 days period using PVC cores with or without a massive addition of crude Arabian Light oil (20 g.kg-1 sed wet.).The results of this study show clearly an important disappearance of saturated hydrocarbons after 1220 days with a preferential disappearance of n-alkanes compared to branched alkanes. This evolution is very well marked in the surface sediments (0-4 cm) but also, at a least degree, in the deeper sediments (8-10 cm). Our results are in good agreement with those related to the evolution of hydrocarbons in highly contaminated sediments by oil spills such as the Amoco-Cadiz in 1978 on the Brittany coasts or the Exxon Valdez in 1989 on the Alaska coasts

Additives as a major source of radiolytic organic byproducts of polyvinyl chloride (PVC)

International audiencePolyvinyl chloride (PVC), one of the most polymeric materials present in the radioactive waste, is exposed to radiooxidation process during disposal and generates many byproducts. Commercial PVC materials usually contain many additives to provide desired properties and to improve their stability during shaping and lifetime. The additives generally delay PVC radiolysis limiting the formation of some PVC transformation compounds, but they can indubitably generate byproducts as well. Hence, the present work investigates the role of the additives in formulated PVC on the nature and kinetics of the released radiolytic compounds. Four PVC samples, one resin, two PVC formulated on purpose and one commercial PVC containing different additives (at least di-isononyl phthalate (DINP) as plasticizer) were exposed to irradiation. Analyses by thermal desorption-GC-MS and solvent extraction coupled with GC-MS were undertaken to identify radio oxidative products. Higher amounts of volatile and non-volatile organic compounds were detected in formulated PVC compared to PVC resin. Some are products coming from the degradation of the polymer chain while the others result mainly from the radiolytic degradation of DINP plasticizer. Commercial PVC containing the widest range of additives (among other lubricants) produced additional byproducts coming from their degradation. Based on the identification and evolution of the radio oxidized products, mechanistic pathways involved in the radiolytic degradation of formulated PVC are proposed

The use of hopanes to track in situ variations in petroleum composition in surface sediments

Alterations in the composition of a Light Arabian crude oil has been studied in situ during 12 months in an artificially contaminated site. After 12 months of experimentation, C17/Pr and C18/Ph ratios could not be used, because the isoprenoïds were no longer stable. In contrast, a high degree of stability of biomarkers, especially hopanes, was observed. These are very useful tools to assess alterations in other less stable classes of saturated compounds (n-alkanes and isoprenoïds) contained in petroleum. Marked degradation of both n-alkanes and isoprenoïds (using 17α21β C30 hopane as “internal standard”) has been evidenced. The use of biomarkers also made it possible to observe a burying process which occurred down to 6 cm deep after 12 months of experimentation

Levels and sources of heavy metals and PAHs in sediment of Djibouti-city (Republic of Djibouti)

International audienc

Chirped attosecond photoelectron spectroscopy

We study analytically the photoionization of a coherent superposition of electronic states and show that chirped pulses can measure attosecond time scale electron dynamics just as effectively as transform-limited attosecond pulses of the same bandwidth. The chirped pulse with a frequency-dependent phase creates the interfering photoelectron amplitudes that measure the electron dynamics. We show that at a given pump-probe time delay the differential asymmetry oscillates as a function of photoelectron energy. Our results suggest that the important parameter for attosecond science is not the pulse duration, but the bandwidth of phased radiation.Peer reviewed: YesNRC publication: Ye

Persistent organic pollutants in sediments of the Wouri Estuary Mangrove, Cameroon: Levels, patterns and ecotoxicological significance

International audienceThe anthropogenic impact in the Wouri Estuary Mangrove located in the rapidly developing urban area of Doula, Cameroon, Africa, was studied. A set of 45 Persistent Organic Pollutant were analysed in surficial mangrove sediments at 21 stations. Chlorinated Pesticides (CLPs), Polychlorinated Biphenyls (PCBs) and Polycyclic Aromatic Hydrocarbons (PAHs) have concentrations ranging from 2.2-27.4, 1.7-31.6 and 83-544 ng/g, respectively. The most abundant CLPs were endosulfan, alachlor, heptachlor, lindane (γ-HCH) and DDT, which metabolites pattern revealed recent use. Selected PAHs diagnostic ratios show pyrolytic input predominantly. The sum of 7 carcinogenic PAHs (ΣC-PAHs) represented 30 to 50% of Total PAHs (TPAHs). According to effect-based sediment quality guidelines, the studied POPs levels imply low to moderate predictive biological toxicity. This study contributes to depict how fare water resources are shifting within what is now termed the Anthropocene due to increasing local pressures in African developing countries

Organic Pollutants Hazard in Sediments and Green Mussels in Jakarta Bay, Indonesia

International audienceOrganic pollutants (PAHs, PCBs, and organochlorine pesticides (OCPs) from sediments and Asian green mussels (Perna viridis) in Jakarta Bay were studied using GC-MS/MS. The PAHs concentration in the sediments ranged from 186.64 to 915.71 µg.kg−1 per sediment dry weight (dw), while the PCBs and the OCPs concentration ranged from 3 to 117 µg.kg−1 and 3 to 17.99 µg.kg−1 per sediment dw, respectively. For the P. viridis, 16 types of PAHs concentration ranged from 591 to 997 µg.kg−1 per dw of mussels, while the OCPs concentration varied from 5 to 6 µg.kg−1 per dw of mussel. The selected PAHs ratios, including Ant/∑178, Fl/∑202, BaAnt/∑228, and IPyr/∑276, potentially showed that the sources of the hydrocarbons in sediments were generally biogenic and terrigenous than for mussels were petroleum source. The concentration of PAHs in mussels was higher than sediments, meanwhile the organic pollutant contains chlorine (PCBs and OCPs) were potentially found in sediments. The reclamation, urban and mangrove areas (stations G and H) in this study found more high risk of than other sampling stations of sediments and mussels. According to the environmental risk assessment parameters (TEL, ERM, and ERL) from the sediment quality guidelines, the stations have various potential ecological risks. P. viridis was shown to be highly contaminated in polluted stations (except station A) that were not recommended for consumption (>200 µg.kg−1 tissue dw)