Introduction Liquid targets using top-of-foil loading concept have been succesfully employed for routine high current production of 18F and 13N at Cyclotope (Houston,TX), over the past ten years1,2. These targets are typically filled with 3.5 ml of water, then pressurized with helium gas at 22 bar and bombarded with 18MeV protons (70–100 µA). Average calculated saturation yield for produc-tion of 18F is ~7.8 GBq/µA (210 mCi/µA) using in-house recycled [18O]-water at approximately 93% enrichment. Reduction of beam power per unit of area is one of the advantages of a tilted entrance-foil geo-metry. Implementation of this target geometry on the ACSI TR19 cyclotron 25degrees upwards irradiation port results in an almost horizontal target entrance foil. A 6ml total cavity volume target allows variable liquid fill volumes of 1.2–4.5 ml for beam current operation from 30–120 µA, resulting in a very efficient use of the costly 18O-water. In a near horizontal installation as in the mayority of cyclotrons, the fill volume flexibility is drastically reduced, having a minimum fill volume of 3.3 ml. At the requirement of Laboratorios Bacon, Cyc-lotope modified the target design with a front mounted collimator compatible with the IBA Cyclone 18/9 cyclotron. A second requirement was to reduce the minimum fill volume for horizontally mounted targets to 2.5 ml or less, while maintaining saturation yield performance. To preserve compatibility with existing IBA targets, the target hardware was modified to operate in self-pressurization mode. This paper presents the results obtained with high and low volume Niobium target inserts (6ml and 4 ml) mounted near horizontally on the IBA Cyclone 18/9 cyclotron and operated in self-pressurization mode. We present pressure/current characteristics, target performance (saturation yield, produced activities, maintenance frequency, FDG yields, etc.). Material and Methods The following targets manufactured by Cyclotope were tested and routinely used for production at Laboratorios Bacon: 1-High Volume Target CY2 model (“American Standard”), 6ml Niobium cavity. 2-Low Volume Target, CY3a model (“Traful”), 4ml Niobium cavity. 3- Low volume Target, CY3b model (“Ferrum”), 4.1ml Niobium cavity. Results and Conclusion The advantages of self-pressurization mode (Laboratorios Bacon setup) are: - Using the vapor pressure as a performance parameter - heat removal by boiling/condensation cycle starts at lower temperature (beam cur-rent) . While, the advantages of the pre-pressurized targets (Cyclotope setup) are: - reduced pressure fluctuations - performance is basically unaffected by plumbing dead volume - flexibility to locate instrumentation farther away from radiation fields - less dependence on fill volume - potential target leaks can be detected before starting an irradiation No significant differences were found in target performance when operated in either pressu-rization mode. The self-pressurizing setup seems to require a sligthly lower fill volume (approxi-mately 5%). The maximum beam current was limited by the foil rupture pressure (~ 40 bar). Safe maximum operating pressure was determined as 30 bar. No foil rupture was experienced during nine months of daily irradiation of these targets in self-pressurizing mode at Laboratorios Bacon. The irradiation parameters and target performance for the different targets are shown in Tables 1 and 2 below. The low volume Traful and Ferrum targets have the best saturation activity vs. fill volume, A(sat)/V, relation. Both targets produce 310 ± 31GBq (8.4 ± 0.8 Ci) of high quali-ty fluoride (F-18) in two hours of irradiation at 70 µA. The low volume targets have a low operation pressure (20bar @ 70µA) when compared to the IBA (NIRTA XL) targets. The typical saturation activity for the low volume targets was 592 ± 59 GBq (16 ± 1.6 Ci) of F-18 at 70 µA, 8.5 GBq/µA (228 mCi/µA) using 2.7ml enriched O-18 water (98 % +). The maintenance interval (> 10 mA.h) is very conveniente to reduce personnel radiation dose. No reduction in FDG yields was observed during that operation interval. In contrast, operation of the high volume targets in pre-presurization mode at the Cyclotope facility results in a higher maximum beam current limit (135 µA) for the same operating pressure (25 bar). Nevertheless, more O-18 water will be required to irradiate at this high current (4.5 ml vs. 3.0 ml). In self-pressurizing mode, a higher filling volume will reduce the expansion volume and, in consequence, the maximum beam current.

第23回名古屋大学年代測定総合研究センターシンポジウム平成22(2010)年度報告

The kinetics of protein phosphorylation and dephosphorylation are tightly controlled by specific kinases and phosphatases; disturbances are often disease-causing. Phosphorylation kinetics are normally monitored using radioactive isotopes of phosphorus, or by using stop-flow techniques. Approaches using mass spectrometry are severely limited by the lack of a stable isotope of phosphorus (other than 31P). The principal aim of this study is to develop a new method to incorporate 18O label into phosphorylation sites of phosphoproteins with a view of applying this method to enhance the detection of phosphorylation by mass spectrometry and to analyze the phosphorylation kinetics of proteins. Aurora-A kinase was selected to explore the possibility of using 18O-labelling to monitor phosphorylation kinetics. The kinase is well characterized, phosphorylated both in human cells and when expressed in recombinant form in E. coli and it contributes to development of some cancers when deregulated. Applying different mass spectrometric approaches resulted in the identification of 19 phosphorylation sites of Aurora-A including five new sites. Using H3P18O4 as a label donor to incorporate 18O into Aurora-A phosphorylation sites showed partial and inconsistent label incorporation. Alternatively, H218O was used to investigate the possibility of label incorporation. Preliminary results, however, showed high complex data which hampered precise identification of phosphopeptides and their labelling state. The labelling experiment was then redesigned in which induction took place in label free medium to allow the light version of the kinase to accumulate, before chasing with 18O label. This design successfully introduced fully labelled P18O3 into Aurora-A phosphorylation sites. LC ESI Q-ToF analysis of 18O labelled Aurora-A sample isolated according to this protocol identified 30 phosphopeptides showing label incorporation, which is double the number of phosphopeptides identified by MASCOT using the same MS analysis. The method was also used to investigate phosphorylation kinetics of Aurora-A. The results suggested differential regulation of phosphorylation sites of Aurora-A as some sites showed early phosphorylation while others were phosphorylated at later stages. Overall, a new approach was developed for enhanced detection of phosphorylation sites and analysis of phosphorylation kinetics.

In this master’s thesis the hydrolytic degradation in 18O-water solutions of six drug substances has been studied. The aim was to develop a mass spectrometric method for easier identification of degradants, since hydrolysis in 18O-water will generate degradants with higher mass compared with hydrolysis in regular water. The degradation was carried out in both acidic and basic conditions. About 10 % degradation was aimed for in the study and the storage time and conditions were adjusted to accommodate that. The samples were then analyzed with UPLC-MS. Separation was achieved on either an Acquity BEH C18 or HSS T3, 100 x 2.1 mm, 1.7 μm column. The mobile phases consisted of water and acetonitrile with the addition of 0.1 % formic acid. Structures for the detected degradants were proposed based on the molecular ion data from the regular and 18O-experiments. Most of these degradants have previously been reported. Structures for some previously unreported degradants are also proposed. These structures should need to be confirmed with future studies. The usefulness of the 18O-method has been evaluated and it was concluded that it is valuable to use as a complement to the generic hydrolytic experiment. In this study, the extra information gained from the 18O-experiment was used to confirm a number of proposed structures. It was also crucial in the rejection of two proposed structures for degradants of duloxetine. The method is most useful when confirming water involvement in reactions, for example in drug degradation. It is also a good alternative for obtaining structural information if the laboratory does not own a high-resolution MS.

農林水産研究情報センターで作成したPDFファイルを使用している。

Introduction Liquid targets using top-of-foil loading concept have been succesfully employed for routine high current production of 18F and 13N at Cyclotope (Houston,TX), over the past ten years1,2. These targets are typically filled with 3.5 ml of water, then pressurized with helium gas at 22 bar and bombarded with 18MeV protons (70–100 µA). Average calculated saturation yield for produc-tion of 18F is ~7.8 GBq/µA (210 mCi/µA) using in-house recycled [18O]-water at approximately 93% enrichment. Reduction of beam power per unit of area is one of the advantages of a tilted entrance-foil geo-metry. Implementation of this target geometry on the ACSI TR19 cyclotron 25degrees upwards irradiation port results in an almost horizontal target entrance foil. A 6ml total cavity volume target allows variable liquid fill volumes of 1.2–4.5 ml for beam current operation from 30–120 µA, resulting in a very efficient use of the costly 18O-water. In a near horizontal installation as in the mayority of cyclotrons, the fill volume flexibility is drastically reduced, having a minimum fill volume of 3.3 ml. At the requirement of Laboratorios Bacon, Cyc-lotope modified the target design with a front mounted collimator compatible with the IBA Cyclone 18/9 cyclotron. A second requirement was to reduce the minimum fill volume for horizontally mounted targets to 2.5 ml or less, while maintaining saturation yield performance. To preserve compatibility with existing IBA targets, the target hardware was modified to operate in self-pressurization mode. This paper presents the results obtained with high and low volume Niobium target inserts (6ml and 4 ml) mounted near horizontally on the IBA Cyclone 18/9 cyclotron and operated in self-pressurization mode. We present pressure/current characteristics, target performance (saturation yield, produced activities, maintenance frequency, FDG yields, etc.). Material and Methods The following targets manufactured by Cyclotope were tested and routinely used for production at Laboratorios Bacon: 1-High Volume Target CY2 model (“American Standard”), 6ml Niobium cavity. 2-Low Volume Target, CY3a model (“Traful”), 4ml Niobium cavity. 3- Low volume Target, CY3b model (“Ferrum”), 4.1ml Niobium cavity. Results and Conclusion The advantages of self-pressurization mode (Laboratorios Bacon setup) are: - Using the vapor pressure as a performance parameter - heat removal by boiling/condensation cycle starts at lower temperature (beam cur-rent) . While, the advantages of the pre-pressurized targets (Cyclotope setup) are: - reduced pressure fluctuations - performance is basically unaffected by plumbing dead volume - flexibility to locate instrumentation farther away from radiation fields - less dependence on fill volume - potential target leaks can be detected before starting an irradiation No significant differences were found in target performance when operated in either pressu-rization mode. The self-pressurizing setup seems to require a sligthly lower fill volume (approxi-mately 5%). The maximum beam current was limited by the foil rupture pressure (~ 40 bar). Safe maximum operating pressure was determined as 30 bar. No foil rupture was experienced during nine months of daily irradiation of these targets in self-pressurizing mode at Laboratorios Bacon. The irradiation parameters and target performance for the different targets are shown in Tables 1 and 2 below. The low volume Traful and Ferrum targets have the best saturation activity vs. fill volume, A(sat)/V, relation. Both targets produce 310 ± 31GBq (8.4 ± 0.8 Ci) of high quali-ty fluoride (F-18) in two hours of irradiation at 70 µA. The low volume targets have a low operation pressure (20bar @ 70µA) when compared to the IBA (NIRTA XL) targets. The typical saturation activity for the low volume targets was 592 ± 59 GBq (16 ± 1.6 Ci) of F-18 at 70 µA, 8.5 GBq/µA (228 mCi/µA) using 2.7ml enriched O-18 water (98 % +). The maintenance interval (> 10 mA.h) is very conveniente to reduce personnel radiation dose. No reduction in FDG yields was observed during that operation interval. In contrast, operation of the high volume targets in pre-presurization mode at the Cyclotope facility results in a higher maximum beam current limit (135 µA) for the same operating pressure (25 bar). Nevertheless, more O-18 water will be required to irradiate at this high current (4.5 ml vs. 3.0 ml). In self-pressurizing mode, a higher filling volume will reduce the expansion volume and, in consequence, the maximum beam current.

Dans le Supergroupe Ouest-Congolais du bassin du Niari-Nyanga (Afrique centrale), les marqueurs des Glaciations Globales Sturtienne et Marinoenne sont représentés par les formations des «Diamictite inférieure» et «Diamictite supérieure».Ce travail de thèse présente une étude à haute résolution du Cap Carbonate associé à la Diamictite supérieure (6 coupes dans le bassin et 2 coupes dans la zone externe de la Chaîne du Mayombe). Les études pétrographiques révèlent la préservation des structures sédimentaires primaires et permettent de définir six microfaciès (MF0 à MF5) caractéristiques des paléoenvironnements de types inter- à supratidaux ou subtidaux. Dans le Cap Carbonate étudié, les indices de Kübler montrent une évolution croissante depuis la diagenèse profonde dans le bassin jusqu'à l'épimétamorphisme dans la zone externe de la Chaîne du Mayombe. Le signal isotopique ([delta]13C et [delta]18O) des Cap Carbonate échantillonnés est généralement reproductible dans le synclinal comme dans la chaîne, avec les valeurs du [delta]13C montrant une excursion négative variant de -2.6 [pour mille] à -5.6 [pour mille]. Les valeurs de d18O oscillent entre -6 [pour mille] et -12 [pour mille]. Par ailleurs, la confrontation des données minéralogiques, chimiques et isotopiques indique une influence négligeable des transformations post-sédimentaires sur la signature isotopique du Cap Carbonate indiquant la préservation des valeurs du [delta]13C de l'océan néoprotérozoïque. Enfin, l'ensemble des données de cette thèse et les résultats préliminaires des « Projets GLANEC» replacés dans un contexte régional permettent de définir le Membre SCIa du synclinal du Niari-Nyanga comme un Cap Carbonate lié à la Glaciation Marinoenne. / Within West-Congolian Supergroup of Niari-Nyanga Basin (Central Africa), the markers of Sturtian and Marinoan Global Glaciations are documented by the so-called «Lower Diamictite» and «Upper Diamictite». This work is based on 6 and 2 lithological sections from the basin and the external zone of the Mayombe fold belt. It corresponds to a high-resolution study of the Cap Carbonate lying unconformably on the Upper Diamictite. Petrographic analyses show preservation of primary sedimentary structures and lead to define six microfacies (MF0 to MF5). These microfacies caracterize paleoenvironments such as inter- to supratidal or subtidal types. Kübler index values of the studied Cap Carbonate display an increasing evolution from East to West, ie from a deep diagenesis in the basin to an epimetamorphism in the Mayombe external zone. Stable isotope signature ([delta]13C, [delta]18O) of the various components of this Cap Carbonate is reproducible throughout the basin as in the Mayombe external zone, with [delta]13C values displaying a negative excursion, decreasing from -2.6 ? to -5.6 ?. [delta]18O values of these components vary between -6 ? and -12 ?. Moreover, comparison between mineralogic, chemical and isotopic data indicates that post-sedimentary transformations had a very negligible influence on the isotopic signature of the Cap Carbonate, indicating preservation of d13C values of the Neoproterozoic ocean. Finally, when they are compared with other regional studies, all data of the present work and the preliminary results of the GLANEC Projects lead to the conclusion that the SCIa Member of the Niari-Nyanga Basin must be considered as a Cap Carbonate related to the Marinoan Global Glaciation.

Aktuelle Klimamodelle prognostizieren, dass viele bedeutendeWaldregionen in Mitteleuropa zukünftig einer steigenden Frequenz und höheren Intensität von Dürreperioden ausgesetzt sein werden. Buchendominierte Wälder bilden einen wichtigen Bestandteil dieser Waldregionen. Der Mangel hinsichtlich der Wasserversorgung ist eine der wichtigsten limitierenden Faktoren für das Wachstum der Pflanzen sowie der damit verbundene reduzierte Zugewinn an Kohlenstoff. Ein weiterer bedeutender Stressfaktor ist die Konkurrenz zwischen sowie innerhalb Pflanzengemeinschaften. Aufgrund dieser Tatsache ist es wichtig, die pflanzenphysiologischen Mechanismen während der Trockenheit sowie interspezifische und intra-spezifische Konkurrenz in buchendominierten Waldökosystemen zu verstehen. Die vorliegende Arbeit untersucht den Zusammenhang von Kohlenstoff- und Wasserhaushalt und deren Wechselwirkungen sowie die Transportwege während der Trockenheit auf unterschiedlichen räumlichen (Blattebene bis Bestandesebene) und zeitlichen (kurzfristig bis langfristig) Skalen. Insgesamt wurden sechs Arten ausgewählt (Fagus sylvatica, Acer platanoides, Fraxinus excelsior, Impatiens noli tangere, Mercurialis annua und Allium ursinum). Alle Arten haben verschiedene Strategien entwickelt, um Konkurrenz und Trockenstress zu bewältigen, zu verhindern oder zu tolerieren. In Abhängigkeit von der Trockenstressintensität wurden geringe Effekte, in der Mesophyllleitfähigkeit (gm), intrinsische Wassernutzungseffizienz (iWUE) sowie in der Transportmenge an neuen Assimilaten beobachtet. / Current climate models predict that many important forest regions in Central Europe will experience increasing frequencies and severities of drought periods. Beech-dominated forests are an important part of these forest regions. Shortage in water supply is one of the most important limiting factors for growth of plants and thereby linked to a reduced carbon gain. Another key stressor is the competition between as well as within a plant communities. Due to this fact it is important to understand the plants physiological mechanisms during drought as well as inter-specific and intra-specific competition in beech dominated forest ecosystems. This present study documents the interrelation of carbon and water balance and the interactions of its pathways during drought on different spatial (leaf area to the stand level) and temporal scales (intra-annual to decadal). Six relevant species were selected in total (tree species: Fagus sylvatica, Acer platanoides, Fraxinus excelsior and species from the understorey of beech dominated forests: Impatiens noli tangere, Mercurialis annua and Allium ursinum). All of them have developed various strategies to cope with competition and avoid or tolerate drought stress. Depending on the drought intensity (e.g. moderate realistic drought) small effects in mesophyll conductance (gm), intrinsic water use efficiency (iWUE) and amount of new assimilates within trees occurred.

Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2016-09-19T17:07:03Z No. of bitstreams: 1 Tese UFF-UPMC Douglas Lessa.pdf: 6010651 bytes, checksum: 86b3d1d49b00abc23751b8883b42dfe0 (MD5) / Made available in DSpace on 2016-09-19T17:07:03Z (GMT). No. of bitstreams: 1 Tese UFF-UPMC Douglas Lessa.pdf: 6010651 bytes, checksum: 86b3d1d49b00abc23751b8883b42dfe0 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geociências - Geoquímica. Niterói, RJ / A presente tese teve o objetivo de reconstruir a paleoceanografia do Sistema de Ressurgência de Cabo Frio (SRCF) nos últimos 12.000 anos através da utilização de proxies ecológicos (comparação entre as assembleias do SRCF com as assembleias das áreas adjacentes com diferentes feições oceanográficas) e geoquímicos de foraminíferos planctônicos, além de obter maior conhecimento sobre a distribuição das espécies sob diferentes configurações oceanográficas, e avaliar e aplicar a recente metodologia de ablação a laser + ICP-MS para análises elementares em carbonatos de foraminíferos. Para isso, 34 topos de box-cores englobando o SRCF e as áreas adjacentes nas bacias de Santos e Campos e dois testemunhos a gravidade foram usados. O agrupamento das assembleias na Margem Continental do Rio de Janeiro (MCRJ) indicou a ocorrência de quatro principais biofáciess espacialmente bem-separadas: biofácies A - talude da bacia de Campos (contribuição de espécies tropicais e subtropicais caracterizando a frente da Corrente do Brasil, CB), biofácies B - bacia de Santos (maiores contribuições de espécies relacionadas à produtividade, caracterizando sinal de mistura de massas de água costeiras produtivas e oceânicas oligotróficas), biofácies C – setor norte do SRCF (contribuições de G. ruber e Globigerina bulloides, caracterizando ambiente de ressurgência com frequentes atenuações por águas quentes) e a biofácies D – setor sul do SRCF (contribuição de espécies indicadoras de águas frias e produtivas, caracterizando uma configuração influenciada pela ressurgência Ekman). Além disso, a distribuição espacial de Globoturborotalita rubescens revelou preferencia desta espécie por águas de plataforma continental e Globigerinella calida sendo associada a pós-ressurgência. Os testemunhos CF10-01B (mais distante da costa) e CF10-09A (mais próximo da costa) cobrem os últimos 11,5 e 7,1 ka cal, respectivamente sendo o primeiro mais influenciado pela Corrente do Brasil, expressando um sinal mais fraco da ressurgência que o segundo. No testemunho CF10-01B, o 18O de G. ruber foi mais variável que o 18O de G. bulloides apresentando dois períodos de diminuição após 9,0 ka cal AP e após 4,0 ka cal AP, enquanto o 18O de G. bulloides diminui após 9,0 ka cal AP e permanece constante até o topo. No testemunho CF10-09A, o 18O das duas espécies variaram de forma antagônica com uma mudança entre 5,0 e 4,5 ka cal AP onde o 18O de G. ruber diminui de -0,4 para -1,0 ‰ e o 18O de G. bulloides aumenta de -0,8 para 0,0 ‰. Os resultados da razão Mg/Ca obtidos pelo método de ablação a laser indicaram uma heterogeneidade intra-câmara que resultou em uma incerteza de 1,49°C para reconstruções com G. ruber e 0,6°C para G. bulloides, assim como amplitudes individuais de 3,0 a 4,0 mmol/mol para G. ruber e de 3,0 a 5,0 mmol/mol para G. bulloides e diferenças significativas entre a última câmara (f) e as anteriores (f-1 e f-2) para as duas espécies. Tais efeitos foram associados ao efeito vital de simbiontes, a grande amplitude de temperatura existente sazonalmente no SRCF e a migração das espécies para águas mais profundas durante a reprodução. As razões Mg/Ca obtidas pelo método clássico foram geralmente mais altas que as razões obtidas pelo método de ablação a laser (LA-ICP-MS) mas se aproximaram e apresentaram variação temporal semelhante aos valores médios obtidos nas câmaras f-1 e f-2. Dessa forma podemos usar a razão Mg/Ca média das câmaras f-1 e f-2 para reconstruções de paleotemperatura de superfície, habilitando também a utilização da diferença entre as razões Mg/Ca das câmaras anteriores e final de G. ruber para reconstruir a estratificação da água. Entretanto, a diferente variabilidade entre a razão Mg/Ca da câmara f de G. ruber e a razão média de G. bulloides indicou possíveis sucessões sazonais, o que nos fez associar as temperaturas reconstruída por G. bulloides como temperaturas da camada de máximo de clorofila, podendo ser associada a intensidade da ressurgência. O período de variação do nível do mar (11,5 – 6,0 ka cal AP) foi marcado pela presença de águas frias, produtivas e homogêneas associadas possivelmente à ressurgência costeira cuja contribuição diminuiu à medida que a transgressão seguia e a frente da CB se aproximava, alcançando um primeiro máximo entre 7,0 e 6,0 ka cal AP no ponto 1 e entre 6,0 e 5,5 ka cal AP no ponto 9, marcado por águas quentes na superfície e frias na subsuperfície. Entre 5,5 e 3,5 ka cal AP, a ressurgência gradualmente se intensifica com maiores efeitos próximo a costa e mais restrita a subsuperfície na porção distal. A influência costeira apresenta um aumento em 5,0 ka cal AP na porção proximal e 4,0 ka cal AP na região distal. Entre 3,5 e 2,5 ka cal AP um forte sinal de águas quentes pouco estratificadas foi observado com maior influência de águas oligotróficas no ponto 9 e mistura de águas costeiras e oceânicas no ponto 1. Após 2,5 ka cal AP, o SRCF adquire suas configurações atuais marcadas por eventos intensos de ressurgência na porção proximal da plataforma e mais restritos a subsuperfície na porção distal. Isso pode ser associado ao fortalecimento da ZCAS ligado a intensificação da monsão Sulamericana no Holoceno Superior devido ao aumento da insolação de verão. / This thesis aimed to rebuild the palaeoceanography of Cabo Frio Upwelling System (CFUS) in the last 12,000 years through the use of ecological (comparison between the CFUS assemblages and adjacent areas assemblages with different oceanographic features) and geochemical proxies of planktonic foraminifera, and obtain more knowledge about the distribution of species under different oceanographic settings, and evaluating and implementing the recent LA-ICP-MS methodology for elemental analysis in foraminifera carbonates. For this, 34 box-cores tops encompassing the CFUS and adjacent areas in the Santos and Campos basins and two gravity cores were used. The group analysis of the assemblages in the Rio de Janeiro Continental Margin (RJCM) indicated the presence of four major biofacies spatially well separated: biofacies A - Campos Basin continental slope (contribution of tropical and subtropical species characterizing the Brazil Current front, BC), biofacies B - Santos basin (largest contributions of productivity related species, characterizing a signal of mixing of coastal productive and oceanic oligotrophic waters), biofacies C - northern sector of CFUS (G. ruber and contributions of Globigerina bulloides, featuring environment with frequent attenuated upwelling by warm water intrusions) and biofacies D - southern sector of CFUS (contribution of cold and productive waters species, featuring the Ekman upwelling setting). In addition, the spatial distribution of Globoturborotalita rubescens revealed preference of this species for continental shelf waters and Globigerinella calida being associated with post-upwelling conditions. The cores CF10-01B (offshore) and CF10-09A (inshore) covered the last 11.5 and 7.1 ka cal, respectively being the first most influenced by the Brazil Current and expressing a weaker upwelling signal than the second. In the core CF10-01B, the G. ruber 18O was more variable than the G. bulloides 18O with two decreases after 9.0 ka cal AP and after 4.0 ka cal BP, while the 18O of G. bulloides decreased only after 9.0 ka cal AP and remains constant up to the top. In the core CF10-09A, the 18O of the two species varied opposite with a change between 5.0 and 4.5 cal ka AP where the 18O G. ruber decreases from -0.4 to -1.0 ‰ and 18O of G. bulloides increases from -0.8 to 0.0 ‰. Mg/Ca ratio results by laser ablation method indicated heterogeneity intra-chamber which resulted in uncertainties for reconstructions up to 1.49°C for G. ruber and up to 0.6°C for G. bulloides as well as individual amplitudes from 3.0 to 4.0 mmol/mol to G. ruber and 3.0 to 5.0 mmol/mol to G. bulloides and significant differences between the last chamber (f) and previous (f-1 and f-2) for both species. These effects were associated with the symbiont vital effect, the wide seasonal temperature range in the SRCF and species migration to deeper waters during reproduction. The Mg/Ca ratio generated by the traditional method were generally higher than the ratios Mg/Ca reconstructed through LA-ICP-MS, although, when compared to the average of f-1 and f-2 chambers only, the values show similar mean and variability indicating both methods agree in reconstruction for surface paleotemperatures. It also allows the use of difference between the ratios of final and previous chamber of G. ruber for paleostratification reconstructions. However, the distinct variability between G. ruber f chamber Mg/Ca ratios and average G. bulloides Mg/Ca ratio indicated possible seasonal succession, which made us associate the temperatures reconstructed by G. bulloides to chlorophyll layer temperatures which may be associated with upwelling intensity. The sea level rise (from 11.5 to 6.0 ka cal BP) was marked by the presence of cold productive and homogeneous waters, possibly associated with coastal upwelling whose contribution gradually decreased during the course of the transgression, followed by the penetration of BC front on the shelf, reaching a first maximum between 7.0 and 6.0 ka cal BP offshore and between 6.0 and 5.5 ka cal BP inshore, marked by warm surface waters and cold subsurface waters. Between 5.5 and 3.5 ka cal BP, the upwelling gradually intensifies mainly inshore and restricted to subsurface offshore. An increased coastal influence is also detected with peaks at 5.0 ka cal BP inshore and 4.0 cal ka BP offshore. Between 3.5 and 2.5 ka cal BP a strong signal of warm water was observed with greater influence of oligotrophic waters inshore and mixture of coastal and oceanic waters offshore. After 2.5 ka cal BP, the SRCF acquires its current settings marked by intense upwelling events, better expressed inshore and restricted to subsurface offshore. This change may correspond to an intensification of the SACZ linked to the strengthening of the South American Monsoon during the late Holocene due to the increase in summer insolation.

La caractérisation géochimique et isotopique des aquifères du Complexe Terminal (CT) du sud tunisien a été effectuée sur la base d'une approche multi isotopique. Cette étude a mis en évidence la continuité hydrogéologique des aquifères du CT en dépit de la variabilité lithologique latérale des formations aquifères et à travers les grands accidents tectoniques. La minéralisation des eaux est acquise par les processus d’interactions eau / roche, la dissolution des évaporites associés à la précipitation de la calcite. Les teneurs en δ18O et δ2H, montrent un fort contraste entre les eaux du CT. La signature isotopique traduit l’effet de l’évaporation manifesté par un enrichissement en δ18O et δ2H. Le marquage isotopique atteste aussi d’un effet de paléorecharge. En outre, les teneurs en 14C couplées aux teneurs en δ13C, ont soutenu la recharge de la nappe au cours de l’Holocène. Le déséquilibre 234U / 238U a été aussi utilisé. Les eaux du CT ont enregistré des teneurs qui varient de 1.5 à 19.5 ppb et des rapports 234U / 238U qui varient de 1.1 à 3.2. La mise en solution de l’uranium est contrôlée par la dissolution de la matrice aquifère. Cette étude a mis en évidence aussi des conditions oxydantes régnant au sein des aquifères du CT. Ces conditions sont propices au lessivage préférentiel de l’234U et dont l’effet marquant les rapports 234U / 238U qui sont >1. L’étude des teneurs en 36Cl et du rapport 36Cl / Cl montre que leur variation est liée aux processus d’évaporation et de dissolution. Les taux d’évaporation et de dissolution calculés sont > 50% traduisant l’effet marquant de ces deux processus sur la variation des teneurs en chlore des eaux du CT. / The geochemical and isotopic characterization of CT aquifers of southern Tunisia was conducted on the basis of a multi isotopic approach. This study highlighted the hydrogeological continuity of the CT aquifers despite the lateral lithological variability of aquifers and through major tectonic accidents. Groundwater mineralization is controlled by water rock interaction and the dissolution of evaporate minerals associated with the calcite precipitation. The δ18O and δ2H composition, show a strong contrast. The isotopic signature reflects the evaporation effect shown by stable isotope enrichment. Isotopic composition also demonstrates a paleorecharge effect. In addition, the 14C content coupled with the contents δ 13C, supported the groundwater recharge in the Holocene period. 234U / 238U disequilibrium was also used. Results indicate a range in 238U concentration and 234U/238U activity ratios of 1.5 to 19 ppb and 1.1 to 3.2 respectively. Our results show that groundwater geochemistry is ultimately a result of lithologic variations associated with water / rock interaction. Results elucidate also the mixing relationships between the different aquifer horizons.In this study, we used also chlorine-36 (36Cl) as a groundwater tracer. The variation in 36Cl content and 36Cl / Cl ratio is essentially related to both evaporation and dissolution processes. Evaporation and dissolution rates recorded values that exceed 50 % showing the major effect of these processes on the change of chloride contents in CT groundwater.