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Introduction: Regional health care networks with interfaces between clinics, general practitioners and patients can act faster when utilizing digital measures. This manuscript describes the establishment of an online video consultation service in a clinic and its broad health care region to exemplify challenges and solutions for potential future approaches from a management perspective.Method: The underlying pilot project was planned and implemented for follow-up monitoring and consultative presentation of orthopedic and trauma patients within the Bundeswehr Medical Service from 2018 to 2020. With predominantly positive evaluation results regarding quality and acceptance among users, this research investigated organizational and processual aspects including total quality management, strategic control and change management approaches.Results: The affected main and subprocesses of patient treatment could be streamlined by the project, as physician recommendations and arrangements could be accelerated and patient travel could be significantly reduced. A SWOT and portfolio analysis showed a high potential for improving existing patient treatment processes for health care enterprises via the use of digital technology. The involved staff should be strategically included at an early stage and continuously involved. By means of a PDCA cycle, the processes of the given project could be exemplarily illustrated with an outlook in the future.Discussion: It has proven successful to consciously use management approaches to establish telemedical integrated care structures in a health region. Recommendations for the strategic introduction of an online video consultation for regional network strengthening and care development for a patient-oriented increase in efficiency could be compiled. [ABSTRACT FROM AUTHOR]

Introduction: Bencubbin-type (CB) and high-metal (CH) chondrites belong to the same clan, due to their similar chemical compositions, e.g., similar oxygen isotopic compositions and high abundance of metal and sulfide. However, whether they derived from the same reservoir in the protoplanetary disk is poorly understood [1, 2]. CB chondrites have large chondrules (up to 20 mm), and these chondrules formed later than chondrules in other groups of chondrites [3, 4], i.e., ~5 Ma after solar system formation. The CB chondrules are also very depleted in moderately volatile elements [5], which may relate to their presumed formation during the collision of two planetesimals [3]. Nucleosynthetic 54Cr isotope variations (expressed as ε54Cr, per ten thousand deviation of mass-independent 54Cr/52Cr isotope ratios relative to terrestrial standards) are a powerful tool to test the genetic relationships among solar system materials [2, 6]. Chromium (Cr) has a 50% condensation temperature of 1291 K [7], and its volatility increases with the fO2 [8]. Mass-dependent Cr isotope variations (expressed as δ53Cr, per mil deviation of mass-dependent 53Cr/52Cr ratios relative to NIST SRM 979) can be used to study isotopic fractionation during evaporation processes [9, 10]. The siderophile nature of Cr also makes it a tracer for metal-silicate segregation. Samples and Methods: We selected four CB chondrites and three CH chondrites (including the data in [2]) for mass-independent Cr isotope measurments by the total evaporation method on Trion TIMS (FUB), ion-exchange column chemistry and the mass spectrometric method is decribed in [11]. The CB chondrules were extracted from the Gujba (fall) meteorite. The δ53Cr values were measured on Triton TIMS (FUB) using double spike techiques [12] with an external 2SD uncertainty of ~0.013 ‰. Results: CB and CH chondrites show homogenous ε54Cr values of 1.51 ± 0.09 (2SD, N = 4) and 1.54 ± 0.13 (2SD, N = 3), respectively. Bulk Gujba has a δ53Cr value of -0.28 ± 0.01 (2SD, N = 2) that is isotopically lighter than its chondrules with δ53Cr values ranging from -0.32 to 0.02. Gujba chondrules have variable Cr contents (2900 - 4000 ppm), Mn/Cr (0.09 - 0.54) and Al/Mg ratios (0.086 - 0.118), and the Mn/Cr and Al/Mg ratios are broadly anticorrelated with the δ53Cr values. Discussion and Conclusion: The ε54Cr similarities between CB and CH chondrites strongly suggests that they formed from similar or the same precursors. Their ε54Cr values are also similar to ε54Cr of CI chondrites (~1.5, [2, 6]) which show the highest ε54Cr value of chondrites, rich in presolar grains. However, CB and CH chondrites do not share common Δ17O compositions. Furthermore, CB and CH chondrites have higher ε54Cr values than the metalbearing CR chondrites, suggesting that the latter derive from another reservoir. Thus, although CB-CH-CR chondrites are all relatively metal-rich compared to other carbonaceous chondrites, the assigned clan designation [13] should be reconsidered. The isotopically heavy Cr in Gujba chondrules compared to the measurement of bulk Gujba could have been caused by Cr loss during the impact processes. This is further suggested by the "heavy" Cr and decreasing Al/Mg and Mn/Cr ratios. Note that, only in oxidized conditions, Cr would be more volatile than Mn [8]. This may further suggest the Gujba CB chondrules formed at a relatively oxidized condition [5]. Alternatively, isotopically heavy Cr in CB chondrules (silicates) could be caused by equilibrium isotope fractionation during metal-silicate segregation, which results in the isotopically light Cr in the matal phase, consistent with the ab initio calculation [14]. 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. [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]

Introduction: Magmatic iron meteorites are remnants of cores of differentiated asteroids that formed during the first few million years of the solar system. Iron meteorites are classified by their mass fractions of siderophile elements (e.g. Ir, Au, Ga, Ge) which are correlated as a result of fractional crystallization. Their trace element abundances and fractionation trends define distinct groups [e.g. 1]. Each of these groups reflects a single parent body with different volatile element contents (e.g. Ga, Ge). In order to understand the fractionation processes of the siderophile volatile elements (SVE) Ag, Te, Se, S, Cd, In and Tl in the parent bodies, we determined the concentrations of these elements along with highly siderophile elements (HSE; Ir, Ru, Pt, Pd) in the relatively volatile-rich IIAB and the volatile-poor IVA iron meteorites. Fractional crystallization models for the IIAB and IVA iron meteorite cores were applied to determine the initial composition of SVE and HSE in the liquid core and to further constrain the composition of these elements in the parent bodies prior to metal-silicate segregation. The newly derived SVE and HSE abundances of the undifferentiated parent bodies are compared with non-carbonaceous meteorites, because Δ17O-ε54Cr genealogy links IIAB to ureilite/acapulcoite-lodranite [2] and IVA to the LL chondrite field [3]. Samples and Method: 10 IIAB and 12 IVA iron meteorites were selected to cover approximately the entire known compositional range of the IIAB and IVA iron meteorite cores. Iron meteorite chips were digested in reverse aqua regia along with a mixture of spike solutions in an High-Pressure-Asher (Anton Parr HPA-S) at 250 °C (P~100 bar) for 16 h. The elements of interest were purified by a three-step anion-cation exchange chromatography procedure, modified from [4,5]. Element analyses were conducted on an ELEMENT XR sector field ICP-MS at Freie Universität Berlin, using hydride generation, Aridus II and Scott type spray chamber sample introduction systems. Results and Discussion: SVEs in IIAB and IVA iron meteorites are depleted to varying degrees compared to modeled core compositions assuming chondritic parent bodies. Silver, Te and Se concentrations in IIAB iron meteorites correlate in logarithmic plots with HSEs, whereas this is not the case for IVA iron meteorites. Concentrations of In and Tl in IIAB and IVA irons are homogeneous within analytical uncertainty and are decoupled from other elements. Mass fractions of trapped sulfides in the analysed IIAB and IVA bulk iron meteorites are ≤0.1 % and were determined by a simple mass balance, assuming the entire amount of S remained in the melt during fractional crystallization. Mass balance calculations using metal-sulfide partition coefficients of SVE show that the contribution of SVE in trapped sulfides in bulk iron meteorites are negligible (<1 %). Fractional crystallization models considering entrapment of metal melt [6] were constrained by parametrization from [7], assuming that the effect of C on solid metal-liquid metal partition coefficients of HSE are negligible. An initial S content of 17 and 3-9 wt.% [8] and an initial P content of 1.0 and 0.25 wt.% [9,10] were assumed for the IIAB and IVA cores, respectively. Fractional crystallization of the SVE was modeled for the IIAB iron meteorite core by linear correlation ("slope method", e.g. [11]) with Pd, and indicate that Ag, Te and Se are moderately incompatible in solid metal relative to liquid metal, while In and Tl were unaffected by fractional crystallization. In contrast, heterogeneous distribution of Ag, Te and Se in IVA iron meteorites cannot be explained by fractional crystallization of metal alone and may suggest that the IVA iron meteorite core underwent protracted admixing of Fe-Ni metal melts with a heterogeneous and depleted SVE composition to an early formed FeNi-FeS core [12]. SVE depleted compositions of the parent bodies were likely caused by early volatile loss during a magma ocean stage or volcanic outgassing under reducing conditions or even earlier during volatile loss from the solar nebula. [ABSTRACT FROM AUTHOR]

Introduction: Volatile elements are depleted in chondrites relative to the bulk solar system composition as represented by CI-chondrites. To disentangle the processes that affected volatile element abundances in the protoplanetary disk and on parent bodies we present high-precision isotope dilution data for 11 volatile elements (S, Cu, Zn, Ga, Se, Ag, Cd, In, Sn, Te and Tl) and Cd and Zn stable isotope compositions for carbonaceous, ordinary, enstatite and Rumuruti chondrites. Results and interpretation: For carbonaceous chondrites, our results confirm that volatile elements with 50% condensation temperatures (TC) between 1040 and 800 K show a progressive depletion with decreasing TC, while volatile elements with 800 K > TC > 500 K are almost unfractionated. This "hockey-stick" depletion pattern [1] represents the primary volatile element signature of the carbonaceous chondrite reservoir in the protoplanetary disk. Ordinary and Rumuruti chondrites show a similar pattern for volatile element depletion but only for elements with TC between 1040 K and 700 K (Cu, Ga, Ag, Zn, Te, Sn). As observed for carbonaceous chondrites, the abundances of plateau volatile elements (Zn, Te, Sn) in ordinary and Rumuruti chondrites covary with the matrix abundance, suggesting that ordinary and Rumuruti chondrites also contain a primitive CI-like matrix component. In contrast to carbonaceous chondrites, S and Se are less depleted, indicating different physicochemical conditions in the formation region of ordinary and Rumuruti chondrites in the protoplanetary disk. The highly unsystematic behavior of the most volatile elements Cd, In and Tl along with Cd and Zn (only ordinary chondrites) stable isotope fractionation suggest secondary redistribution processes on the respective parent bodies due to open system thermal metamorphism. Enstatite chondrites show no systematic volatile element abundance patterns with TC. Notably, their depletion pattern reveals similarities with evaporation experiments using carbonaceous chondrite powder under reduced conditions [1]. However, the rather uniform depletion of Cd, In and Tl together with unfractionated Cd and Zn stable isotope compositions in type 3 and 4 enstatite chondrites argue against extensive parent body alteration. [ABSTRACT FROM AUTHOR]