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Introduction: The vast majority of approved meteorites listed in the Meteoritical Bulletin Database are finds from either Antarctica or hot deserts (North Africa, Chile, Arabia, etc.). Knowing the terrestrial age, i.e., the time span between the fall of the meteorite and its recovery on Earth, is crucial for i) understanding the parameters influencing meteorite weathering on Earth, ii) studying meteorite pairing, iii) investigating the meteorite flux in the past, and in a more general sense v) increasing our understanding of the dynamics of small bodies in the solar system. The terrestrial age is often determined using the cosmogenic nuclide 14C. For such studies, the 14C production rate, i.e., the 14C activity concentration at the time of fall, must be known. However, this value depends on the chemical composition of the meteorite and on shielding, i.e., preatmospheric radius and depth of the sample in the preatmospheric meteorite, and is therefore not well constrained, especially not for large meteorites and strewnfields. To circumvent this problem, the 10Be/14C system is often applied, i.e., instead of using only the 14C production rate, the 14C/10Be production rate ratio is used, which is less dependent on chemical composition and shielding. For a reliable application, the dependence (or independence) of the 14C/10Be production rate ratio on meteorite type and shielding needs to be known in some detail. However, for the 14C/10Be dating system to be applicable, 10Be must be in saturation, i.e., the cosmic ray exposure age must be longer than about 5-7 Ma. Experimental: In this study, we determine 14C and 10Be activity concentrations in freshly fallen meteorites. We selected the meteorites Bensour (LL6), Boumdeid (L6), Mt. Tazerzait (L5), and Sayh al Uhaymir 606 (H5). Carbon-14 is extracted using the 14C extraction line in our laboratory at the University of Bern, Switzerland [1,2] and the 14C/12C ratios are measured at the MICADAS system at the LARA laboratory at the University of Bern [3]. The 10Be activity concentrations have already been measured using the ASTER accelerator mass spectrometer at CEREGE in Aix-en-Provence, France [4,5]. In addition and especially to further support the data, we also measure the noble gas isotopes 3He, 4He, 20Ne, 21Ne, and 22Ne in aliquots of the samples to, i) determine the preatmospheric dimensions and ii) to determine the cosmic ray exposure age to prove or reject that 10Be is in saturation. The noble gas measurements were all performed at the University of Bern. While the 10Be data have already been measured, the noble gases are currently measured and we already measured first aliquots for 14C. We will present all data at the conference. Model calculations: This study is complemented by new model calculations for 14C, 10Be, 21Ne, and 22Ne to study if and (if yes) how the 14C/10Be production rate ratio depends on meteorite type and shielding and especially if such a hypothetical dependence can be corrected for by using cosmogenic 22Ne/21Ne ratios. The model is essentially the same used already to establish galactic cosmic ray gradients in the solar system [6]. Here the model is extended to 14C and Ne isotopes. Summary: In this study we will significantly improve the basics of the 14C and 14C/10Be dating systems for terrestrial ages of meteorites. Thanks to the additionally measured noble gas data we will have a good knowledge about the constancy of the 14C/10Be ratio and the 14C production rate with respect to meteorite type and shielding. Thanks to our study we expect to significantly reduce the systematic uncertainties for terrestrial ages in the age range (0-50) ka. [ABSTRACT FROM AUTHOR]

Introduction: Most iron meteorites are interpreted to represent fragments of the cores of asteroids, hence their formation represents a significant stage of planetary differentiation. The formation and crystallization of these cores dates back to the first few million years of the solar system. Stable isotopes of siderophile elements, such as Cr [1, 2] may fractionate during metal-silicate equilibration, which can provide constraints for the reconstruction of the physicochemical environment of core formation processes. However, it is difficult to determine the original Cr isotope composition of iron meteorites, because exposure to cosmic rays can significantly modify the Cr isotope compositions of samples with high Fe/Cr ratios and long exposure times, leading to enrichments in 53Cr and 54Cr [3]. This can result in a negative correlation between Cr contents and d53Cr of iron meteorite metal [4]. Chromite and Fe-Cr sulfide (daubréelite) in iron meteorites have very low Fe/Cr ratios and thus, may better preserve the original Cr isotope composition of iron meteorites before irradiation [5]. Samples and Methods: Seven chromite/daubréelite samples of iron meteorites, belonging to IIIAB (Cape York and Saint Aubin), IVA (Yanhuitlan and Duchesne) and IIAB (Agoudal, Sikhote Alin and NWA 11420) groups are investigated which, wereare from a previously studiedy for mass-independent Cr isotope variations [5]. We employed the Triton TIMS (Freie Universität Berlin) and double spike techniques to measure to their d53Cr values, with an external 2SD precision of better than 0.02 ‰. The detailed analytical method is described in [6]. Results: Two IIIAB chromites show the same d53Cr (per thousand 53Cr/52Cr ratios relative to NIST SRM 979) values of -0.08 ± 0.01‰ (2SD), while the chromite/daubréelite in IVA and IIAB iron meteorites show large d53Cr variation, from -1.29‰ to -0.74‰ and from -0.64‰ to -0.08‰, respectively. The bulk iron meteorites have variable Ni, Au and Ir contents, which are not correlated with the d53Cr values of the chromites. Discussion and Conclusion: The Cr stable isotope fractionation of more than 1 permil for some chromites most likely reflects kinetic isotope fractionation, caused by diffusion processes during core crystallization and cooling. Two IIIAB iron meteorites with different Ni, Au and Ir contents (8.50%, 1.01 ppm and 2.90 ppm; 10.33%, 2.59 ppm and 0.02 ppm respectively) have chromites with the same d53Cr values of -0.08 ± 0.01‰. These data may reflect equilibrium isotope fractionation and the d53Cr value may be representative for the IIIAB iron meteorite parent body. However, during crystallization chromite can become enriched in heavy Cr isotopes by ~0.15‰ as was shown in relatively oxidized terrestrial rocks [7]. Hence, the IIIAB bulk iron meteorites may have a lighter d53Cr value relative to chromite (around ~-0.23‰). Since the chromites from these three iron meteorite groups have ordinary chondrite (OC)-like e54Cr values [5, 8, 9] and chondrites show heterogeneous d53Cr values [6], we assume that the d53Cr values of OCs (-0.10 ± 0.04‰; 2SD, N = 20) are representative of the bulk parent bodies of the iron meteorites [6, 10]. The d53Cr difference between IIIAB iron meteorites and OCs, d53CrIIIAB-OCs = ~-0.13‰, potentially indicates Cr stable isotope fractionation during core formation of the IIIAB parent body. This observation is consistent with ab-initio calculations suggesting that the metal phase is enriched in isotopically light Cr compared to coexisting silicates during their segregation [11]. Indeed, silicates of the aubrite and ureilite parent bodies are enriched in isotopically heavy Cr, which suggests the asteroid cores should be dominated by isotoplically light Cr. When Cr stable isotopes are used for tracking planetary differentiation, core formation must be considered, especially for small planetary bodies [12, 13]. Acknowledgements: K. Z. thanks the Alexander von Humboldt Foundation for a postdoctral fellowship. H.B. is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation-#263649064-TRR 170). We thank Frederic Moynier for generously providing the Cr spikes, and Peng Ni for fruitful discussion. [ABSTRACT FROM AUTHOR]

Résumé La consommation d’aliments peu courants dans notre alimentation traditionnelle est parfois l’occasion d’en découvrir le potentiel allergisant. Nous rapportons ici le premier cas français d’allergie alimentaire aux baies de goji, prouvée par test cutané et immunoblot. Cette observation est d’autant plus intéressante qu’elle est survenue lors de la première ingestion de baies, suggérant une réactivité croisée avec d’autres végétaux chez cette patiente par ailleurs pollinique. Eating foods not commonly found in our traditional diet can occasionally reveal their allergenic potential. Herein, we report the first case in France of allergy to goji berries as attested by skin prick and immunoblot tests. This case is particularly interesting, since it occurred after the initial ingestion of berries, suggesting the existence of cross-reactivity with other plant substances in this female patient, who was also presenting pollen allergies. [ABSTRACT FROM AUTHOR]

The use of extracorporeal membrane oxygenation (ECMO) is becoming a popular tool in the treatment of cardiogenic shock. We present two case reports where classical veno-arterial peripherally cannulated ECMO therapy proved insufficient with profuse cerebral hypoxemia. After augmenting the setting into veno-veno-arterial ECMO, we achieved a remarkable improvement of all oxygenation parameters. The simultaneous use of veno-venous and veno-arterial ECMO might display as a novel strategy to counteract the coronary and cerebral hypoxemia in veno-arterial ECMO therapy in patients with therapy-refractory cardiogenic shock or in combined cardiopulmonary failure. In this manuscript, the veno-veno-arterial ECMO setup is described in full detail and different venous cannulas are discussed. [ABSTRACT FROM PUBLISHER]