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Zusammenfassung: Der vorliegende Bericht beschreibt eine 62-jährige Patientin mit progredienter Gangstörung und Panzytopenie. Als Diagnose ergab sich eine funikuläre Myelose sowie eine megaloblastäre Anämie infolge eines ausgeprägten Vitamin-B12-Mangels. Als Ursache hierfür fand sich nach Ausschluss aller Differenzialdiagnosen eine seit Jahren bestehende streng vegetarische Ernährung. Unter der eingeleiteten Therapie mit Vitamin-B12-Substitution besserte sich das klinische und laborchemische Bild innerhalb von 3 Monaten.

Purpose: Entrepreneurial Ecosystems (EES) is among the fastest growing entrepreneurship research topics. With even greater vigour, the non-scientific world of economic development agencies, administrations and policymakers has adopted the construct and applies it widely “in the field”, often lacking a solid empirical foundation and pursuing sub-optimal approaches. Improving policy instruments for EES development requires a data driven approach to first understand an EES of a specific region before making any attempts to change it. The paper showcases an empirical approach to create empirically rooted EES policy implications, contributing to closing the gap for insight in regional EES data of sub-national regions. Design/methodology/approach: Exploring a mixed method design, utilising quantitative Global Entrepreneurship Monitor data and combining it with EES stakeholder interviews, focusing on dysfunctions, redundancies, power asymmetries and cut off elements as well as in-layer division and public organisation behaviour. Findings: One finding is, that regional economic development agencies (EDA), as a main public instrument to foster regional entrepreneurial activity, seem to bring the potential of a negative impact on Entrepreneurial Ecosystems bottom-up development and the ability to become self-sustained if they assume the role of competitors towards private organisations and businesses. Research limitations/implications: As other work on EES, the approach used in this paper only sub-optimally covers temporal system dynamics. Practical implications: This paper contributes to future EES support policies being rooted in an empirical foundation. Originality/value: This paper not only progresses the empirical basis for research on regional EES but also lays the foundation for specific policy implications for a sub-national level entrepreneurial ecosystem.

Climate change threatens ecosystems worldwide, yet their potential future resilience remains largely unquantified. In recent years many studies have shown that biodiversity, and in particular functional diversity, can enhance ecosystem resilience by providing a higher response diversity. So far these insights have been mostly neglected in large-scale projections of ecosystem responses to climate change. Here we show that plant trait diversity, as a key component of functional diversity, can have a strikingly positive effect on the Amazon forests’ biomass under future climate change. Using a terrestrial biogeochemical model that simulates diverse forest communities on the basis of individual tree growth, we show that plant trait diversity may enable the Amazon forests to adjust to new climate conditions via a process of ecological sorting, protecting the Amazon’s carbon sink function. Therefore, plant trait diversity, and biodiversity in general, should be considered in large-scale ecosystem projections and be included as an integral part of climate change research and policy.

We discuss the possibility of Earth-type planets in the planetary system of 55 Cancri, a nearby G8 V star, which is host to two, possibly three, giant planets. We argue that Earth-type planets around 55 Cancri are in principle possible. Several conditions are necessary. First, Earth-type planets must have formed despite the existence of the close-in giant planet(s). In addition, they must be orbitally stable in the region of habitability considering that the stellar habitable zone is relatively close to the star compared to the Sun because of 55 Cancri's low luminosity and may therefore be affected by the close-in giant planet(s). We estimate the likelihood of Earth-type planets around 55 Cancri based on the integrated system approach previously considered, which provides a way of assessing the long-term possibility of photosynthetic biomass production under geodynamic conditions.

Um extrasolare Planetensysteme zu untersuchen, müssen wir zuerst unser eigenes Sonnensystem verstehen. Die Erdsystemanalyse gibt uns Hinweise darauf, wie sich ein erdähnlicher Planet unter dem Einfluss eines sich verändernden Sterns verhält und welche Selbstregulationsprozesse zur Stabilisierung seiner Bewohnbarkeit ablaufen. Dabei spielt die Geodynamik eine entscheidende Rolle. Die Definition der bewohnbaren Zone ist eng mit den Bedingungen für das Auftreten von Leben, so wie wir es kennen, verbunden. Die Existenz von flüssigem Wasser ist der zentrale Punkt. Ausgehend von den Ergebnissen für ein virtuelles Erdsystem, könnten sich in unserer Milchstraße etwa 50 Millionen bewohnbare Planeten befinden.

The long‐term co‐evolution of the geosphere–biospere complex from the Proterozoic up to 1.5 billion years into the planet's future is investigated using a conceptual earth system model including the basic geodynamic processes. The model focusses on the global carbon cycle as mediated by life and driven by increasing solar luminosity and plate tectonics. The main CO2sink, the weathering of silicates, is calculated as a function of biologic activity, global run‐off and continental growth. The main CO2source, tectonic processes dominated by sea‐floor spreading, is determined using a novel semi‐empirical scheme. Thus, a geodynamic extension of previous geostatic approaches can be achieved. As a major result of extensive numerical investigations, the “terrestrial life corridor”, i.e., the biogeophysical domain supporting a photosynthesis‐based ecosphere in the planetary past and in the future, can be identified. Our findings imply, in particular, that the remaining life‐span of the biosphere is considerably shorter (by a few hundred million years) than the value computed with geostatic models by other groups. The “habitable‐zone concept” is also revisited, revealing the band of orbital distances from the sun warranting earth‐like conditions. It turns out that this habitable zone collapses completely in some 1.4 billion years from now as a consequence of geodynamics.

A 2-dimensional extension of the simple Lovelock-Watson model for geosphere-biosphere feedback is introduced and discussed. Our enriched version also takes into account various pertinent physical, biological, and civilisatory processes like lateral heat transport, species competition, mutation, germination, and habitat fragmentation. The model is used as a caricature of the Earth System, which allows potential response mechanisms of the biosphere to environmental stress (as generated, e.g., by global warming or anthropogenic land-cover change) to be investigated qualitatively. Based on a cellular automaton representation of the system, extensive calculations are performed. They reveal a number of remarkable and, partially, counter-intuitive phenomena: our model biosphere is able to control almost perfectly the geophysical conditions for its own existence. If the environmental stress exceeds certain thresholds, however, life breaks down on the artificial planet via a first-order phase transition, i.e., in a non-reversible way. There is a close connection between self-stabilizing capacity, biodiversity and geometry of habitat fragmentation. It turns out, in particular, that unrestricted Darwinian competition, which reduces the number of co-existing species, is the best guarantee for survival of the artificial ecosphere as a whole.

Structures resulting from biogenic carbonate cementation of microbial mats in Recent siliciclastic tidal flat sediments of the North Sea are analyzed quantitatively by a novel combination of scanning electron microscopy and energy-dispersive X-ray spectrometry (SEM/EDX) imaging and subsequent multifractal analysis. Evaluation of calcium distribution patterns and their links to sediment-intrinsic mineralization processes show that the applied geometrical technique is an efficient tool for detecting microscopic variations in elemental distributions and related minerals within sedimentary matrices. Two main conclusions can be drawn: (i) magnesian calcite is a rapidly formed product of the early diagenesis of organic matter in Recent bioactive marine sediments; and (ii) multifractal spectra are measures for the spatial inhomogeneity of authigenic calcification processes acting on the sedimentary structure. This implies that elemental distribution patterns in a sedimentary system are scale-independent phenomena. Processes causing such patterns have occurred over certain periods with varying rates and on different scales. The detection of multifractal measures also opens a way towards a systematic survey of dynamic processes occurring in sedimentary structures.

A simple model has been designed to describe the interaction of climate and biosphere. Carbon dioxide, understood as a major emitted gas, leads to a change of global climate. Economic interpretation of the model is based on the maximisation of the global CO2cumulative emissions. The two most important profiles of emission have been obtained: optimal and multi-exponential suboptimal profiles, each displaying different characteristics.