Acquisition of solar wind implanted neon by terrestrial precursor material resembled by iron meteorites and interplanetary dust: implications for the early evolution of the Earth´s mantle-atmosphere system

Studying the origin and evolution of cosmo- and geochemical reservoirs particularly requires knowledge about the composition and occurrence of the inert noble gases (He, Ne, Ar, Kr, Xe). Earth's atmosphere is characterized by a "planetary" noble gas signature, i.e., depleted from solar element abundances more intensively in lighter than in heavier gases, whereas Earth's interior hosts light noble gases (He and Ne) with a distinct "solar" composition. In particular, Ne isotopic ratios of both the convecting and more primitive mantle, the latter sampled by oceanic island basalts (OIBs), resemble the solar wind (SW) implanted Ne-B component in meteorites with 20Ne/22NeNe-B ~12.7. The atmosphere, instead, displays a lower 20Ne/22Ne ratio of 9.80. The reservoir of the primitive noble gas signatures, traditionally assumed to be isolated in the deep mantle, is not precisely located and some models speculate about Earth’s core as possible source. High resolution release experiments on interior samples of the iron meteorite Washington County (WC) were carried out in this study to identify volume correlated trapped noble gases and to investigate the possibility of noble gas partitioning into metal upon core segregation. Consisting of a mixture of predominantly cosmogenic and solar components, with only minor atmospheric additions, gases are released from schreibersite ((Fe,Ni)3P) at ~1100 °C and kamacite-taenite (Fe,Ni) at ≳1400 °C. The solar signatures are distinct in Ne and He/Ne isotopic ratios with clear 4He excess. Ar, Kr and Xe isotopic ratios are either dominated by spallation or are overprinted by air contamination. Measured 20Ne concentrations of ~4*10-8 cm³STP/g imply that solar wind-implantation into terrestrial precursors and incorporation of <1% core material that resembled Washington County metal would have been sufficient to provide solar type Ne in the core that satisfies observed mantle fluxes. This would be consistent with the core as potential source region. The actual acquisition of the light solar noble gases on Earth can be either explained by solar nebula gas dissolution into a magma ocean or accretion of solar wind irradiated material. The solar wind implantation model is assessed by applying constraints for the present terrestrial influx of particles ranging from 10-16–1025 g, and the size-specific Ne inventory of extraterrestrial matter. Present-day Ne contributions to Earth’s surface peak at interplanetary dust particle sizes of ~9 µm which contain a mean 20Ne/22Ne ratio of 12.61±0.41. This value represents Ne-B in unablated solar wind saturated particle surfaces and dominates the inventory of irradiated, though volatile-poor, matter that accreted to form Earth in the inner Solar system. This is opposed to volatile-rich objects from the outer Solar system containing planetary Ne-A with 20Ne/22Ne ~8.20. The data compilations allow determining the mass and size dependent upper atmosphere Ne flux and infer the contribution during early Earth formation of a) surface correlated Ne-B, dominated by ~75 µm particles with high surface/volume ratio and b) volume correlated Ne-A, dominated by larger bodies. The Ne-acquisition scenario considers delivery of solar wind implanted Ne-B shortly after dissipation of disk gas and Ne incorporation into Earth with 20Ne/22Ne: 12.61±0.41 by dissolution into a magma ocean before the Moon-forming impact. The late veneer contribution of Ne-A to degassed mantle Ne-B establishes the atmospheric inventory with 20Ne/22Ne: 9.80. The model calculations show that, because dominated by implanted components in cosmic dust, only a fraction of a few % of irradiated precursor material is sufficient to account for the solar Ne budget of Earth, thus, demonstrating the significance of dust accretion for the origin of volatiles

Intracardiac thrombus formation after the Fontan operation

AbstractObjectives: Intracardiac thrombus formation is suspected to be a specific sequela after the Fontan operation and is difficult to determine by means of routine transthoracic echocardiography. The aim of our study was to evaluate the occurrence of intracardiac thrombi in the different types of Fontan modifications and to identify predisposing risk factors. Methods: We evaluated 52 patients who had undergone a Fontan-type operation and were free of symptoms regarding thrombosis as determined by transesophageal echocardiography. Results: In 17 (33%) patients thrombus formation could be found without clinical evidence of thromboembolic complications. Neither underlying morphologic disease nor age at operation, type of Fontan operation, sex, follow-up interval, arrhythmias, or laboratory or hemodynamic findings could be identified as predisposing risk factors. Conclusion: In patients having had a Fontan operation with inadequate or without anticoagulation medication, we would recommend routine transesophageal echocardiography to exclude eventual thrombi. Because of the high incidence of thrombi, we suggest oral anticoagulation therapy in all patients. (J Thorac Cardiovasc Surg 2000;119:745-52

Highly photoluminescent copper carbene complexes based on prompt rather than delayed fluorescence

Linear two-coordinate copper complexes of cyclic (alkyl)(amino)-carbenes (CAAC)CuX (X = halide) show photoluminescence with solid-state quantum yields of up to 96%; in contrast to previously reported Cu photoemitters the emission is independent of temperature over the range T = 4 – 300 K and occurs very efficiently by prompt rather than delayed fluorescence, with lifetimes in the sub-nanosecond range

Evaluation of Madurahydroxylactone as a Slow Release Antibacterial Implant Coating

Madurahydroxylactone (MHL), a secondary metabolite with antibacterial activity was evaluated for its suitability to generate controlled drug release coatings on medical implant materials. A smooth and firmly attached layer could be produced from a precursor solution on various metallic implant materials. In physiological salt solutions these coatings dissolved within a time period up to one week. A combination of MHL with a broad spectrum fluoroquinolone antibiotic was used to create a coating that was active against all bacterial strains tested. The time period during which the coating remained active against Pseudomonas aeruginosa was investigated. The results indicated a delayed drug release from single layer coatings in the course of seven days. MHL was biocompatible in cell culture assays and could after a delay even serve as a cell adhesion substrate for human or murine cells. The findings indicate a potential for MHL for the generation of delayed release antimicrobial implant coatings

Improvement in long-term survival after hospital discharge but not in freedom from reoperation after the change from atrial to arterial switch for transposition of the great arteries

ObjectiveTo compare survival, freedom from reoperation, and functional status between atrial switch and arterial switch operations for transposition of the great arteries.MethodsData from 88, 329, and 512 patients who underwent Mustard, Senning, and arterial switch operations between 1974 and 2006 were analyzed.ResultsIn-hospital mortalities were 8.0% for Mustard, 4.6% for Senning, and 6.4% for arterial switch. Presence of ventricular septal defect (hazard ratio 3.3, P < .001) was the only risk factor for in-hospital mortality in multivariate analysis. Follow-up for Mustard was 22.6 ± 8.1 years, for Senning was 18.2 ± 5.7 years, and for arterial switch was 9.5 ± 5.7 years. Highest survival at 20 years was after arterial switch (96.6% ± 1.3%), followed by Senning (92.6% ± 1.5%) and Mustard (82.4% ± 4.3%). Transposition with ventricular septal defect (hazard ratio 3.1, P < .001), transposition with ventricular septal defect and left ventricular outflow tract obstruction (hazard ratio 3.0, P = .029), and Mustard operation (hazard ratio 2.1, P = .011) emerged as risk factors for late death, with arterial switch a protective factor (hazard ratio 0.3, P = .010). Highest freedom from reoperation at 20 years was after Senning (88.7% ± 1.9%), followed by arterial switch (75.0% ± 6.4%) and Mustard (70.6% ± 5.4%). Presence of complex transposition (hazard ratio 2.1, P < .001), previous palliative operation (hazard ratio 1.8, P = .016), surgery between 1985 and 1995 (hazard ratio 2.6, P = .002), surgery after 1995 (hazard ratio 3.5, P < .001), and Mustard operation (hazard ratio 3.3, P < .001) emerged as risk factors for reoperation.ConclusionChange from atrial to arterial switch led to improved long-term survival after hospital discharge but not to lower incidence of reoperation. Survival and freedom from reoperation are determined by morphology

Digitalisierung und Energiesystemtransformation : Chancen und Herausforderungen

Welche Rolle spielt die Digitalisierung mit der Vielzahl ihrer Methoden und Anwendungen für die Energiewende - also für die Transformation unseres Energiesystems im Sinne der vereinbarten Klimaschutzziele? Ist sie notwendige Voraussetzung für den Systemumbau und ermöglicht beispielsweise erst den Übergang auf ein nahezu vollständig erneuerbares Energiesystem (Enabler) oder ist sie lediglich ein nützliches, den Umbau beschleunigendes Hilfsmittel (Facilitator)? Welche Veränderungen sind durch die Ziele der Energiewende getrieben und welche durch die Verbreitung von Techniken der Digitalisierung? All dies waren Fragen, die im Rahmen der Jahrestagung 2018 des Forschungsverbunds Erneuerbare Energien unter dem Titel "Die Energiewende - smart und digital" behandelt wurden. Dieser einführende Beitrag versucht einige Anhaltspunkte zur Beantwortung dieser Fragen zu liefern und in das Thema einzuführen

Which Anesthesia Regimen Is Best to Reduce Morbidity and Mortality in Lung Surgery? A Multicenter Randomized Controlled Trial.

BACKGROUND One-lung ventilation during thoracic surgery is associated with hypoxia-reoxygenation injury in the deflated and subsequently reventilated lung. Numerous studies have reported volatile anesthesia-induced attenuation of inflammatory responses in such scenarios. If the effect also extends to clinical outcome is yet undetermined. We hypothesized that volatile anesthesia is superior to intravenous anesthesia regarding postoperative complications. METHODS Five centers in Switzerland participated in the randomized controlled trial. Patients scheduled for lung surgery with one-lung ventilation were randomly assigned to one of two parallel arms to receive either propofol or desflurane as general anesthetic. Patients and surgeons were blinded to group allocation. Time to occurrence of the first major complication according to the Clavien-Dindo score was defined as primary (during hospitalization) or secondary (6-month follow-up) endpoint. Cox regression models were used with adjustment for prestratification variables and age. RESULTS Of 767 screened patients, 460 were randomized and analyzed (n = 230 for each arm). Demographics, disease and intraoperative characteristics were comparable in both groups. Incidence of major complications during hospitalization was 16.5% in the propofol and 13.0% in the desflurane groups (hazard ratio for desflurane vs. propofol, 0.75; 95% CI, 0.46 to 1.22; P = 0.24). Incidence of major complications within 6 months from surgery was 40.4% in the propofol and 39.6% in the desflurane groups (hazard ratio for desflurane vs. propofol, 0.95; 95% CI, 0.71 to 1.28; P = 0.71). CONCLUSIONS This is the first multicenter randomized controlled trial addressing the effect of volatile versus intravenous anesthetics on major complications after lung surgery. No difference between the two anesthesia regimens was evident