29 results on '"Sebilo, M."'
Search Results
2. Stable C and N isotope variation during anaerobic digestate composting and in the compost-amended soil-plant system
- Author
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Nogués, I., Rumpel, C., Sebilo, M., Vaury, V., Moral, R., and Bustamante, M.A.
- Published
- 2023
- Full Text
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3. Groundwater quality assessment combining supervised and unsupervised methods
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Ratolojanahary, R., Ngouna, R. Houé, Medjaher, K., Dauriac, F., and Sebilo, M.
- Published
- 2019
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4. Geochemical identity of pre-Dogon and Dogon populations at Bandiagara (Mali, 11th–20th cent. AD)
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Maurer, A.-F., Person, A., Zazzo, A., Sebilo, M., Balter, V., Le Cornec, F., Zeitoun, V., Dufour, E., Schmidt, A., de Rafélis, M., Ségalen, L., and Bedaux, R.
- Published
- 2017
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5. The Pliensbachian-Toarcian paleoclimate transition: New insights from organic geochemistry and C, H, N isotopes in a continental section from Central Asia
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Tramoy, R., Schnyder, J., Nguyen Tu, T.T., Yans, J., Jacob, J., Sebilo, M., Derenne, S., Philippe, M., Huguet, A., Pons, D., and Baudin, F.
- Published
- 2016
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6. Curative vs. preventive management of nitrogen transfers in rural areas: Lessons from the case of the Orgeval watershed (Seine River basin, France)
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Garnier, J., Billen, G., Vilain, G., Benoit, M., Passy, P., Tallec, G., Tournebize, J., Anglade, J., Billy, C., Mercier, B., Ansart, P., Azougui, A., Sebilo, M., and Kao, C.
- Published
- 2014
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7. Nitrogen Changes between Rural and Peri-Urban Stream Subsurface Waters (Yzeron Stream, France)
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Aucour, A.M., Bariac, T., Breil, P., Namour, P., Schmitt, L., Sebilo, M., and Zuddas, P.
- Published
- 2013
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8. Patterns in δ¹⁵N in roots, stems, and leaves of sugar maple and American beech seedlings, saplings, and mature trees
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Pardo, L. H., Semaoune, P., Schaberg, P. G., Eagar, C., and Sebilo, M.
- Published
- 2013
9. Nitrate dynamics in artificially drained nested watersheds
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Billy, C., Birgand, F., Sebilo, M., Billen, G., Tournebize, J., and Kao, C.
- Published
- 2011
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10. Influence of diet compositions and drinking waters on the stables carbon and oxygen isotopes ratios of gallus gallus eggs
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Segalen, L., Mills, Maryse, Sebilo, M., Labourdette, N., Vaury, V., Nys, Yves, ProdInra, Migration, Université Pierre et Marie Curie - Paris 6 (UPMC), Unité de Recherches Avicoles (URA), Institut National de la Recherche Agronomique (INRA), Institut d'écologie et des sciences de l'environnement de Paris (iEES Paris), Institut National de la Recherche Agronomique (INRA)-Sorbonne Université (SU)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)
- Subjects
[SDV] Life Sciences [q-bio] ,[SDV]Life Sciences [q-bio] ,[INFO]Computer Science [cs] ,[INFO] Computer Science [cs] ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2013
11. Oxygen isotopic composition of phosphate in lake ecosystems: strategies and expectations of a research project comparing oligotrophic and eutrophic Europea Large Lakes Symposium
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Pistocchi, Chiara, Tamburini, F, Sebilo, M, Lazzarotto, J, Baneschi, I, Silvestri, Nicola, Bonari, Enrico, and Dorioz, J. M.
- Published
- 2012
12. Spatial distribution of PAH concentrations and stable isotope signatures (δ13C, δ15N) in mosses from three European areas – Characterization by multivariate analysis.
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Foan, L., Leblond, S., Thöni, L., Raynaud, C., Santamaría, J.M., Sebilo, M., and Simon, V.
- Subjects
MOSSES ,POLYCYCLIC aromatic hydrocarbon analysis ,MOLECULAR weights ,ISOTOPIC signatures ,STABLE isotope analysis ,EMISSIONS (Air pollution) ,STATISTICAL correlation ,REGRESSION analysis - Abstract
Polycyclic aromatic hydrocarbon (PAH) concentrations and N, C stable isotope signatures were determined in mosses Hypnum cupressiforme Hedw. from 61 sites of 3 European regions: Île-de-France (France); Navarra (Spain); the Swiss Plateau and Basel area (Switzerland). Total PAH concentrations of 100–700 ng g
−1 , as well as δ13 C values of −32 to −29‰ and δ15 N values of −11 to −3‰ were measured. Pearson correlation tests revealed opposite trends between high molecular weight PAH (4–6 aromatic rings) content and δ13 C values. Partial Least Square regressions explained the very significant correlations (r > 0.91, p < 0.001) between high molecular weight PAH concentrations by local urban land use (<10 km) and environmental factors such as elevation and pluviometry. Finally, specific correlations between heavy metal and PAH concentrations were attributed to industrial emissions in Switzerland and road traffic emissions in Spain. [Copyright &y& Elsevier]- Published
- 2014
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13. Denitrification in a hyporheic riparian zone controlled by river regulation in the Seine river basin (France).
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Curie, F., Ducharne, A., Sebilo, M., and Bendjoudi, H.
- Subjects
DENITRIFICATION ,CHEMICAL reduction ,NITRATES ,CARBON ,OXIDATION-reduction reaction ,WATER temperature ,RIPARIAN areas ,RIVERS - Abstract
The article presents the result of the study concerning the denitrification and its development in a hyporheic riparian zone controlled by river regulation in the Siene River in France. It mentions that the riparian zone between the chalky hillsides and the river shows an important depletion of nitrate during the summer and autumn period. This depletion is attributed to denitrification which goes with a consumption of dissolved organic carbon and a decrease of redox potential. Moreover, it keeps the wetness of the riparian zone constant which allows the isolation of high temperature in summer and autumn as an important factor for denitrification.
- Published
- 2009
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14. A long-term view of nutrient transfers through the Seine river continuum
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Billen, G., Garnier, J., Némery, J., Sebilo, M., Sferratore, A., Barles, S., Benoit, P., and Benoît, M.
- Subjects
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NITROGEN , *PHOSPHORUS , *SILICA , *HYDROLOGIC models , *DRAINAGE , *LAND use - Abstract
Abstract: A model (the Riverstrahler model) is used to describe nutrient transfer and transformation at the scale of the whole drainage network of the Seine based on information concerning the basic mechanisms governing N, P and Si inputs to the drainage network and in-stream transformation and retention. It was used to calculate the budget of these nutrients through the whole river continuum from land to sea. With the help of historical documents, the constraints used as forcing function in this model were reconstructed to express the changing conditions of land-use and urban population over the last five hundred years. The corresponding scenarios were run for different hydrological regimes including dry, mean and wet conditions. The results were validated on the long-term series of nutrient measurements spanning more than a century available at some stations on the Seine, upstream and downstream of the city of Paris. The model was also used to explore past and future trends in nutrient loading, retention and delivery to the coastal zone, in response to human management of the terrestrial watershed. Beside the initial pristine state, used as an idealized reference state (with N, P and Si delivered fluxes of about 45–110 kg N km−2 yr−1, 2–5 kg P km−2 yr−1, 510–1325 kg Si km−2 yr−1), four periods were distinguished. The first one is that of the traditional cottage economy which prevailed, with quite a constant total population, until the end of the 18th century. N, P and Si fluxes were about 235–750 kg N km−2 yr−1, 15–60 kg P km−2 yr−1 and 425–1280 kg Si km−2 yr−1, depending on hydrological conditions. The second period, from the beginning of the 19th century to about the 1950′s, corresponded to rapid increase in the total and urban population with a corresponding increase of point sources of N and P. From 1950 onwards, modern farming practices resulted in a dramatic increase in diffuse sources of nitrogen and to a lesser extent phosphorus: riverine N and P export reached 1320–2800 kg N km−2 yr−1, and 310–340 kg P km−2 yr−1: silica export remained fairly constant at around 410–1260 kg Si km−2 yr−1 depending on the hydrological conditions. In the 1990′s, the fourth period is represented by a stabilized population and improved wastewater treatment, when the export of phosphorus is reduced to values as low as 40–60 kg P km−2 yr−1, but without as effective a reduction of nitrogen export. This represents an unprecedented situation for the marine coastal system, i.e. a shift from nitrogen to phosphorus limitation, as nitrogen is still delivered far in excess of the amount of silica available for diatom blooms. [Copyright &y& Elsevier]
- Published
- 2007
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15. Photodegradation of the main synthetic musk (HHCB) in water: kinetic study and influencing factors.
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Turan H, Sebilo M, Pigot T, and Monperrus M
- Abstract
Galaxolide (HHCB) is the most common synthetic musk compound detected in numerous daily products. Despite its persistence in the aquatic environment, the photodegradation of HHCB remains poorly understood. In this study, we investigated the direct and indirect photolysis kinetics of HHCB under simulated sunlight and UVC light. Our aim was to determine the role of reactive oxygen species (ROS) responsible for HHCB degradation in the aquatic environment and to identify its transformation products. The influence of environmental factors on indirect photolysis was investigated by testing both synthetic waters (containing humic acid, carbonate (CO
3 2- ), and nitrate (NO3 - )) and real waters (riverine and effluent). Hydrogen peroxide (H2 O2 /UVC) was tested to simulate the wastewater treatment process. Quencher experiments were conducted to identify the role of ROS in HHCB photodegradation, including hydroxyl radicals (˙OH), carbonate radicals (CO3 ˙- ), triplet states of dissolved organic matter (3 DOM*), and singlet oxygen (1 O2 ). The results clearly indicated that HHCB was efficiently degraded by direct photolysis under both light conditions. The presence of H2 O2 led to the most efficient HHCB degradation due to the high production of ˙OH induced under UVC. Indirect photolysis contribution was observed, induced by ˙OH, CO3 ˙- ,3 DOM*, and1 O2 to different extents depending on the light and matrix composition. The experiments led to the detection of transformation products: HHCB lactone, a well-known transformation product, and two other substances with proposed structures. This study provides a comprehensive identification of the processes involved in the direct and indirect photodegradation of HHCB, which could serve as the basis for evaluating and modeling the fate of HHCB in aquatic environments.- Published
- 2024
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16. Synergies of chemodenitrification and denitrification in a saline inland lake.
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Margalef-Marti R, Thibault De Chanvalon A, Anschutz P, Amouroux D, and Sebilo M
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- Iron chemistry, Oxidation-Reduction, Nitrogen analysis, Ecosystem, Water Pollutants, Chemical analysis, Water Pollutants, Chemical metabolism, Denitrification, Lakes chemistry, Geologic Sediments chemistry, Nitrates analysis, Nitrites chemistry, Nitrites analysis
- Abstract
The interconnection between biotic and abiotic pathways involving the nitrogen and iron biogeochemical cycles has recently gained interest. While lacustrine ecosystems are considered prone to the biotic nitrate reduction (denitrification), their potential for promoting the abiotic nitrite reduction (chemodenitrification) remains unclear. In the present study, batch incubations were performed to assess the potential for chemodenitrification and denitrification in the saline inland lake Gallocanta. Sulfidic conditions are found in top sediments of the system while below (5-9 cm), it presents low organic carbon and high sulfate and ferrous iron availability. Anoxic incubations of sediment (5-9 cm) and water from the lake with nitrite revealed potential for chemodenitrification, especially when external ferrous iron was added. The obtained isotopic fractionation values for nitrite (ɛ
15 NNO2 ) were -6.8 and -12.3 ‰ and therefore, fell in the range of those previously reported for the nitrite reduction. The more pronounced ɛ15 NNO2 (-12.3 ‰) measured in the experiment containing additional ferrous iron was attributed to a higher contribution of the chemodenitrification over biotic denitrification. Incubations containing nitrate also confirmed the potential for denitrification under autotrophic conditions (low organic carbon, high ferrous iron). Higher reaction rate constants were found in the experiment containing 100 μM compared to 400 μM nitrate. The obtained ɛ15 NNO3 values (-8.5 and -15.1 ‰) during nitrate consumption fell in the range of those expected for the denitrification. A more pronounced ɛ15 NNO3 (-15.1 ‰) was determined in the experiment presenting a lower reaction rate constant (400 μM nitrate). Therefore, in Gallocanta lake, nitrite generated during nitrate reduction can be further reduced by both the abiotic and biotic pathways. These findings establish the significance of chemodenitrification in lacustrine systems and support further exploration in aquatic environments with different levels of C, N, S, and Fe. This might be especially useful in predicting nitrous oxide emissions in natural ecosystems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
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17. Combined use of 87 Sr/ 86 Sr and carbon isotopes with multielemental analysis for the geographical authentication of Tunisian and European olive oils.
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G Nasr E, Epova EN, Barre J, Sebilo M, de Diego A, Souissi R, Abderrazak H, and Donard OFX
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- Olive Oil, Carbon Isotopes analysis, Strontium analysis, France, Strontium Isotopes analysis, Isotopes analysis, Trace Elements analysis
- Abstract
The geographical authentication in the agrifood industry has become a major issue to guarantee the quality of food products. Olive oil (OO) is particularly a complex matrix and establishing a reliable approach for linking OO samples to their origin is an analytical challenge. In this study, the isotopic composition of carbon, strontium and the concentrations of seventeen elements were determined in OOs from Tunisia, Southern France and the South Basque country. The preliminary results overlapped and showed that, taken individually, the isotopic and elemental approaches were not discriminant. A linear discriminant analysis applied to δ
13 C,87 Sr/86 Sr and to the concentrations of 4 selected trace elements (Fe, Mn, V and Cr) allowed to classify, with high resolution, olive oils into 3 groups according to their provenance. The combination of the plant growing environment, the geological background, the mineral composition of the soil and the production process lead to a novel approach to deal with fraudulent practices in OO sector., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)- Published
- 2023
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18. Benthic nitrate removal capacity in marine mangroves of Guadeloupe, Lesser Antilles.
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Laverman AM, Sebilo M, Tocny J, and Gros O
- Subjects
- Guadeloupe, Organic Chemicals, Carbon analysis, Nitrates, Geologic Sediments
- Abstract
Mangrove sediments are known to be potentially active reducing zones for nitrogen removal. The goal of this work was to investigate the potential for nitrate reduction in marine mangrove sediments along a canal impacted by anthropogenic activity (Guadeloupe, Lesser Antilles). To this end, the effect of nitrate concentration, organic carbon load, and hydraulic retention time was assessed as factors affecting these nitrate reduction rates. Nitrate reduction potential was determined using flow-through reactors in marine mangrove sediments collected along "The Canal des Rotours" in Guadeloupe. Potential nitrate reduction rates, in the presence of indigenous organic carbon, generally increased upon increasing nitrate supply from around 120 nmol cm
-3 h-1 (low nitrate) up to 378 nmol cm-3 h-1 (high nitrate). The potential for nitrate reduction increased significantly with the addition of mangrove leaves, whereas the addition of simple, easily degradable carbon (acetate) resulted in an almost fivefold increase in nitrate reduction rates (up to 748 nmol cm-3 h-1 ). The hydraulic retention time also had an impact on the nitrate reducing capacity due to an increased contact time between nitrate and the benthic microbial community. Marine mangrove sediments have a high potential to mitigate nitrogen pollution, mainly governed by the presence of large amounts of degradable carbon in the form of litter. The mangrove sediments from this Caribbean island, currently exposed to a small tidal effect, could increase their nitrate elimination capacities due to prolonged water retention via engineering., (© 2023 The Authors. Journal of Environmental Quality published by Wiley Periodicals LLC on behalf of American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.)- Published
- 2023
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19. Iron isotopic fractionation driven by low-temperature biogeochemical processes.
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Yin NH, Louvat P, Thibault-DE-Chanvalon A, Sebilo M, and Amouroux D
- Subjects
- Temperature, Iron Isotopes analysis, Iron Isotopes metabolism, Isotopes, Bacteria metabolism, Oxidation-Reduction, Chemical Fractionation, Iron chemistry, Ferric Compounds chemistry
- Abstract
Iron is geologically important and biochemically crucial for all microorganisms, plants and animals due to its redox exchange, the involvement in electron transport and metabolic processes. Despite the abundance of iron in the earth crust, its bioavailability is very limited in nature due to its occurrence as ferrihydrite, goethite, and hematite where they are thermodynamically stable with low dissolution kinetics in neutral or alkaline environments. Organisms such as bacteria, fungi, and plants have evolved iron acquisition mechanisms to increase its bioavailability in such environments, thereby, contributing largely to the iron cycle in the environment. Biogeochemical cycling of metals including Fe in natural systems usually results in stable isotope fractionation; the extent of fractionation depends on processes involved. Our review suggests that significant fractionation of iron isotopes occurs in low-temperature environments, where the extent of fractionation is greatly governed by several biogeochemical processes such as redox reaction, alteration, complexation, adsorption, oxidation and reduction, with or without the influence of microorganisms. This paper includes relevant data sets on the theoretical calculations, experimental prediction, as well as laboratory studies on stable iron isotopes fractionation induced by different biogeochemical processes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)
- Published
- 2023
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20. Upside down sulphate dynamics in a saline inland lake.
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Margalef-Marti R, Sebilo M, Thibault De Chanvalon A, Anschutz P, Charbonnier C, Lauga B, Gonzalez-Alvarez I, Tessier E, and Amouroux D
- Abstract
The sulphur cycle has a key role on the fate of nutrients through its several interconnected reactions. Although sulphur cycling in aquatic ecosystems has been thoroughly studied since the early 70's, its characterisation in saline endorheic lakes still deserves further exploration. Gallocanta Lake (NE Spain) is an ephemeral saline inland lake whose main sulphate source is found on the lake bed minerals and leads to dissolved sulphate concentrations higher than those of seawater. An integrative study including geochemical and isotopic characterization of surface water, porewater and sediment has been performed to address how sulphur cycling is constrained by the geological background. In freshwater and marine environments, sulphate concentration decreases with depth are commonly associated with bacterial sulphate reduction (BSR). However, in Gallocanta Lake sulphate concentrations in porewater increase from 60 mM at the water-sediment interface to 230 mM at 25 cm depth. This extreme increase could be caused by dissolution of the sulphate rich mineral epsomite (MgSO
4 ·7H2 O). Sulphur isotopic data was used to validate this hypothesis and demonstrate the occurrence of BSR near the water-sediment interface. This dynamic prevents methane production and release from the anoxic sediment, which is advantageous in the current context of global warming. These results underline that geological context should be considered in future biogeochemical studies of inland lakes with higher potential availability of electron acceptors in the lake bed compared to the water column., (© 2023. The Author(s).)- Published
- 2023
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21. Olive Oil Traceability Studies Using Inorganic and Isotopic Signatures: A Review.
- Author
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Nasr EG, Epova EN, Sebilo M, Larivière D, Hammami M, Souissi R, Abderrazak H, and Donard OFX
- Subjects
- Geography, Olive Oil, Strontium, Isotopes, Soil
- Abstract
The olive oil industry is subject to significant fraudulent practices that can lead to serious economic implications and even affect consumer health. Therefore, many analytical strategies have been developed for olive oil's geographic authentication, including multi-elemental and isotopic analyses. In the first part of this review, the range of multi-elemental concentrations recorded in olive oil from the main olive oil-producing countries is discussed. The compiled data from the literature indicates that the concentrations of elements are in comparable ranges overall. They can be classified into three categories, with (1) Rb and Pb well below 1 µg kg
-1 ; (2) elements such as As, B, Mn, Ni, and Sr ranging on average between 10 and 100 µg kg-1 ; and (3) elements including Cr, Fe, and Ca ranging between 100 to 10,000 µg kg-1 . Various sample preparations, detection techniques, and statistical data treatments were reviewed and discussed. Results obtained through the selected analytical approaches have demonstrated a strong correlation between the multi-elemental composition of the oil and that of the soil in which the plant grew. The review next focused on the limits of olive oil authentication using the multi-elemental composition method. Finally, different methods based on isotopic signatures were compiled and critically assessed. Stable isotopes of light elements have provided acceptable segregation of oils from different origins for years already. More recently, the determination of stable isotopes of strontium has proven to be a reliable tool in determining the geographical origin of food products. The ratio87 Sr/86 Sr is stable over time and directly related to soil geology; it merits further study and is likely to become part of the standard tool kit for olive oil origin determination, along with a combination of different isotopic approaches and multi-elemental composition.- Published
- 2022
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22. Incidence of cardiometabolic diseases in a Lesotho HIV cohort: Evidence for policy decision-making.
- Author
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Sebilo M, Ledibane NRT, and Takuva S
- Abstract
Background: Antiretroviral treatment (ART) has been associated with the development of certain cardiometabolic diseases (CMDs). The burden of CMDs amongst ART-experienced patients in sub-Saharan Africa was unknown., Objective: We quantified the burden of CMDs and identified the associated risk factors in a large treatment cohort on ART at a high-volume facility in Lesotho., Methods: In this retrospective cohort study, we extracted data from the daily dispensing electronic system and routine clinical records of 785 adults on ART between 2011 and 2015 in Maseru, Lesotho. CMD was defined as a diagnosis of hypertension, diabetes mellitus or dyslipidaemia (singly or collectively). Descriptive statistics were used to describe the disease burden; Kaplan-Meier curves and cause-specific Cox proportional hazards models were fitted to examine the impact of the ART regimen and identify the risk factors associated with the occurrence of CMD., Results: Of the 785 participants, 473 (60%) were women. The median age of the group was 42 years, interquartile range (IQR), 36-51 years. The overall incidence of CMD was 5.6 (95% confidence interval [CI] = 4.4-7.1) per 100 person-months of follow-up. The median time to onset of CMD was 16.6 months (IQR = 7.4-23.4). ART was not associated with the occurrence of CMD (cause-specific hazard ratio [CHR] = 1.55; 95% CI = 0.14-16.85; P = 0.72). Higher body mass index (BMI) was associated with the occurrence of diabetes mellitus (CHR = 1.19; 95% CI = 1.14-1.38; P = 0.026)., Conclusion: The incidence of CMD in this relatively young patient population is low yet noteworthy. We recommend that patients living with HIV and AIDS should be routinely screened for CMD. Higher BMI is generally associated with the occurrence of CMD., Competing Interests: The authors declare that they have no financial or personal relationships that may have inappropriately influenced them in writing this article., (© 2021. The Authors.)
- Published
- 2021
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23. Controls on the Isotopic Composition of Nitrite (δ 15 N and δ 18 O) during Denitrification in Freshwater Sediments.
- Author
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Sebilo M, Aloisi G, Mayer B, Perrin E, Vaury V, Mothet A, and Laverman AM
- Abstract
The microbial reduction of nitrate, via nitrite into gaseous di-nitrogen (denitrification) plays a major role in nitrogen removal from aquatic ecosystems. Natural abundance stable isotope measurements can reveal insights into the dynamics of production and consumption of nitrite during denitrification. In this study, batch experiments with environmental bacterial communities were used to investigate variations of concentrations and isotope compositions of both nitrite and nitrate under anoxic conditions. To this end, denitrification experiments were carried out with nitrite or nitrate as sole electron acceptors at two substrate levels respectively. For experiments with nitrate as substrate, where the intermediate compound nitrite is both substrate and product of denitrification, calculations of the extent of isotope fractionation were conducted using a non-steady state model capable of tracing chemical and isotope kinetics during denitrification. This study showed that nitrogen isotope fractionation was lower during the use of nitrite as substrate (ε = -4.2 and -4.5‰ for both treatments) as compared to experiments where nitrite was produced as an intermediate during nitrate reduction (ε = -10 and -15‰ for both treatments). This discrepancy might be due to isotopic fractionation within the membrane of denitrifiers. Moreover, our results confirmed previously observed rapid biotic oxygen isotope exchange between nitrite and water.
- Published
- 2019
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24. Legacy of contaminant N sources to the NO 3 - signature in rivers: a combined isotopic (δ 15 N-NO 3 - , δ 18 O-NO 3 - , δ 11 B) and microbiological investigation.
- Author
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Briand C, Sebilo M, Louvat P, Chesnot T, Vaury V, Schneider M, and Plagnes V
- Subjects
- Environmental Monitoring, Nitrogen Cycle, Nitrogen Isotopes, Oxygen Isotopes, Water Microbiology, Nitrates analysis, Nitrogen Oxides analysis, Rivers, Water analysis, Water chemistry, Water Pollutants, Chemical analysis
- Abstract
Nitrate content of surface waters results from complex mixing of multiple sources, whose signatures can be modified through N reactions occurring within the different compartments of the whole catchment. Despite this complexity, the determination of nitrate origin is the first and crucial step for water resource preservation. Here, for the first time, we combined at the catchment scale stable isotopic tracers (δ
15 N and δ18 O of nitrate and δ11 B) and fecal indicators to trace nitrate sources and pathways to the stream. We tested this approach on two rivers in an agricultural region of SW France. Boron isotopic ratios evidenced inflow from anthropogenic waters, microbiological markers revealed organic contaminations from both human and animal wastes. Nitrate δ15N and δ18 O traced inputs from the surface leaching during high flow events and from the subsurface drainage in base flow regime. They also showed that denitrification occurred within the soils before reaching the rivers. Furthermore, this study highlighted the determinant role of the soil compartment in nitrate formation and recycling with important spatial heterogeneity and temporal variability., Competing Interests: The authors declare no competing financial interests.- Published
- 2017
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25. Reply to Castellano and David: Long-term fate of nitrate fertilizer and nitrate from agricultural catchments.
- Author
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Sebilo M, Mayer B, Nicolardot B, Pinay G, and Mariotti A
- Subjects
- Environmental Monitoring statistics & numerical data, Environmental Pollution analysis, Fertilizers analysis, Groundwater chemistry, Nitrates analysis, Plants metabolism, Soil chemistry
- Published
- 2014
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26. Spatial distribution of PAH concentrations and stable isotope signatures (δ13C, δ15N) in mosses from three European areas--characterization by multivariate analysis.
- Author
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Foan L, Leblond S, Thöni L, Raynaud C, Santamaría JM, Sebilo M, and Simon V
- Subjects
- Air Pollution statistics & numerical data, Carbon Isotopes analysis, France, Industry, Metals, Heavy analysis, Multivariate Analysis, Nitrogen Isotopes analysis, Spain, Switzerland, Air Pollutants analysis, Bryophyta chemistry, Bryopsida chemistry, Environmental Monitoring, Polycyclic Aromatic Hydrocarbons analysis
- Abstract
Polycyclic aromatic hydrocarbon (PAH) concentrations and N, C stable isotope signatures were determined in mosses Hypnum cupressiforme Hedw. from 61 sites of 3 European regions: Île-de-France (France); Navarra (Spain); the Swiss Plateau and Basel area (Switzerland). Total PAH concentrations of 100-700 ng g(-1), as well as δ(13)C values of -32 to -29‰ and δ(15)N values of -11 to -3‰ were measured. Pearson correlation tests revealed opposite trends between high molecular weight PAH (4-6 aromatic rings) content and δ(13)C values. Partial Least Square regressions explained the very significant correlations (r > 0.91, p < 0.001) between high molecular weight PAH concentrations by local urban land use (<10 km) and environmental factors such as elevation and pluviometry. Finally, specific correlations between heavy metal and PAH concentrations were attributed to industrial emissions in Switzerland and road traffic emissions in Spain., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
27. Long-term fate of nitrate fertilizer in agricultural soils.
- Author
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Sebilo M, Mayer B, Nicolardot B, Pinay G, and Mariotti A
- Subjects
- Colorimetry, France, Mass Spectrometry, Nitrates pharmacokinetics, Nitrogen Isotopes analysis, Oxygen Isotopes analysis, Time Factors, Environmental Monitoring statistics & numerical data, Environmental Pollution analysis, Fertilizers analysis, Groundwater chemistry, Nitrates analysis, Plants metabolism, Soil chemistry
- Abstract
Increasing diffuse nitrate loading of surface waters and groundwater has emerged as a major problem in many agricultural areas of the world, resulting in contamination of drinking water resources in aquifers as well as eutrophication of freshwaters and coastal marine ecosystems. Although empirical correlations between application rates of N fertilizers to agricultural soils and nitrate contamination of adjacent hydrological systems have been demonstrated, the transit times of fertilizer N in the pedosphere-hydrosphere system are poorly understood. We investigated the fate of isotopically labeled nitrogen fertilizers in a three-decade-long in situ tracer experiment that quantified not only fertilizer N uptake by plants and retention in soils, but also determined to which extent and over which time periods fertilizer N stored in soil organic matter is rereleased for either uptake in crops or export into the hydrosphere. We found that 61-65% of the applied fertilizers N were taken up by plants, whereas 12-15% of the labeled fertilizer N were still residing in the soil organic matter more than a quarter century after tracer application. Between 8-12% of the applied fertilizer had leaked toward the hydrosphere during the 30-y observation period. We predict that additional exports of (15)N-labeled nitrate from the tracer application in 1982 toward the hydrosphere will continue for at least another five decades. Therefore, attempts to reduce agricultural nitrate contamination of aquatic systems must consider the long-term legacy of past applications of synthetic fertilizers in agricultural systems and the nitrogen retention capacity of agricultural soils.
- Published
- 2013
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28. Identification of the nitrate contamination sources of the Brusselian sands groundwater body (Belgium) using a dual-isotope approach.
- Author
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Mattern S, Sebilo M, and Vanclooster M
- Subjects
- Belgium, Environmental Monitoring, Groundwater chemistry, Nitrates chemistry, Nitrogen Isotopes analysis, Oxygen Isotopes analysis, Silicon Dioxide chemistry, Groundwater analysis, Nitrates analysis, Silicon Dioxide analysis, Water Pollutants, Chemical analysis
- Abstract
Isotopic fingerprinting is an advanced technique allowing the classification of the nitrate source pollution of groundwater, but needs further development and validation. In this study, we performed measurements of natural stable isotopic composition of nitrate ((15)N and (18)O) in the groundwater body of the Brussels sands (Belgium) and studied the spatial and temporal dynamics of the isotope signature of this aquifer. Potential nitrogen sources sampled in the region had isotopic signatures that fell within the corresponding typical ranges found in the literature. For a few monitoring stations, the isotopic data strongly suggest that the sources of nitrate are from mineral fertiliser origin, as used in agriculture and golf courses. Other stations suggest that manure leaching from unprotected stockpiles in farms, domestic gardening practices, septic tanks and probably cemeteries contribute to the nitrate pollution of this groundwater body. For most monitoring stations, nitrate originates from a mixing of several nitrogen sources. The isotopic signature of the groundwater body was poorly structured in space, but exhibited a clear temporal structure. This temporal structure could be explained by groundwater recharge dynamics and cycling process of nitrogen in the soil-nitrogen pool.
- Published
- 2011
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29. Origin of nitrogen in reforested lignite-rich mine soils revealed by stable isotope analysis.
- Author
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Chabbi A, Sebilo M, Rumpel C, Schaaf W, and Mariotti A
- Subjects
- Carbon analysis, Germany, Plant Leaves chemistry, Soil analysis, Trees, Carbon Isotopes analysis, Mining, Nitrogen analysis, Nitrogen Isotopes analysis, Pinus chemistry
- Abstract
Restoration of the nitrogen cycle is an important step in the recovery of an ecosystem after mining. Carbon and nitrogen in rehabilitated lignite containing mine soils can be derived from plant material as well as from lignite inherent to the parent substrate. We assessed the use elemental and stable carbon and nitrogen isotope measurements to trace the orgin of soil nitrogen and applied these techniques to elucidate the origin of mineral N in the soil and the soil solution. The conceptual approach of this study included physical fractionation in addition to sampling of vegetation and soil from a lignite-containing mine site rehabilitated in 1985 with Pinus Nigra. We studied the elemental and isotopic composition of bulk samples as well as isolated fractions and soil solution. Our data indicate that the stable carbon and nitrogen isotopic composition of the soil samples are the result of mixing between plant material and substrate inherent lignite. delta15N isotopes may be used as indicators of nitrogen contribution from plants to solid samples as well as soil solution. N-isotope composition of ammonia shows low spatial and interannual variability, despite strong concentration changes. Plant-derived nitrogen contributes in higher amounts to the soil solution compared to the bulk mineral soil.
- Published
- 2008
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