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Abstract: We sampled the upper water column for living planktic foraminifera along the SW-African continental margin. The species Globorotalia inflata strongly dominates the foraminiferal assemblages with an overall relative abundance of 70–90%. The shell δ 18O and δ 13C values of G. inflata were measured and compared to the predicted oxygen isotope equilibrium values (δ 18Oeq) and to the carbon isotope composition of the total dissolved inorganic carbon (δ 13CDIC) of seawater. The δ 18O of G. inflata reflects the general gradient observed in the predicted δ 18Oeq profile, while the δ 13C of G. inflata shows almost no variation with depth and the reflection of the δ 13CDIC in the foraminiferal shell seems to be covered by other effects. We found that offsets between δ 18Oshell and predicted δ 18Oeq in the surface mixed layer do not correlate to changes in seawater [CO3 2−]. To calculate an isotopic mass balance of depth integrated growth, we used the oxygen isotope composition of G. inflata to estimate the fraction of the total shell mass that is grown within each plankton tow depth interval of the upper 500 m of the water column. This approach allows us to calculate the Δδ 13Cinterval added-DIC; i.e. the isotopic composition of calcite that was grown within a given depth interval. Our results consistently show that the Δδ 13CIA-DIC correlates negatively with in situ measured [CO3 2−] of the ambient water. Using this approach, we found Δδ 13CIA-DIC/[CO3 2−] slopes for G. inflata in the large size fraction (250–355 μm) of −0.013‰ to 0.015‰ (μmol kg− 1)− 1 and of −0.013‰ to 0.017‰ (μmol kg− 1)− 1 for the smaller specimens (150–250 μm). These slopes are in the range of those found for other non-symbiotic species, such as Globigerina bulloides, from laboratory culture experiments. Since the Δδ 13CIA-DIC/[CO3 2−] slopes from our field data are nearly identical to the slopes established from laboratory culture experiments we assume that the influence of other effects, such as temperature, are negligibly small. If we correct the δ 13C values of G. inflata for a carbonate ion effect, the δ 13Cshell and δ 13CDIC are correlated with an average offset of 2.11. [Copyright &y& Elsevier]

Vasovagal syncope is a common cause of recurrent syncope. Clinically, these episodes may present as an isolated event with an identifiable trigger, or manifest as a cluster of recurrent episodes warranting intensive evaluation. The mechanism of vasovagal syncope is incompletely understood. Diagnostic tools such as implantable loop recorders may facilitate the identification of patients with arrhythmia mimicking benign vasovagal syncope. This review focuses on the management of vasovagal syncope and discusses the non-pharmacological and pharmacological treatment options, especially the use of midodrine and selective serotonin reuptake inhibitors. The role of cardiac pacing may be meaningful for a subgroup of patients who manifest severe bradycardia or asystole but this still remains controversial.