Discontinuity in the responses of ecosystem processes and multifunctionality to altered soil community composition

Ecosystem management policies increasingly emphasize provision of multiple, as opposed to single, ecosystem services. Management for such "multifunctionality" has stimulated research into the role that biodiversity plays in providing desired rates of multiple ecosystem processes. Positive effects of biodiversity on indices of multifunctionality are consistently found, primarily because species that are redundant for one ecosystem process under a given set of environmental conditions play a distinct role under different conditions or in the provision of another ecosystem process. Here we show that the positive effects of diversity (specifically community composition) on multifunctionality indices can also arise from a statistical fallacy analogous to Simpson's paradox (where aggregating data obscures causal relationships). We manipulated soil faunal community composition in combination with nitrogen fertilization of model grassland ecosystems and repeatedly measured five ecosystem processes related to plant productivity, carbon storage, and nutrient turnover. We calculated three common multifunctionality indices based on these processes and found that the functional complexity of the soil communities had a consistent positive effect on the indices. However, only two of the five ecosystem processes also responded positively to increasing complexity, whereas the other three responded neutrally or negatively. Furthermore, none of the individual processes responded to both the complexity and the nitrogen manipulations in a manner consistent with the indices. Our data show that multifunctionality indices can obscure relationships that exist between communities and key ecosystem processes, leading us to question their use in advancing theoretical understanding-and in management decisions-about how biodiversity is related to the provision of multiple ecosystem services.

Glauben als Grundlage - Die Rezeption Michael Polanyis im Gespräch von Theologie und Naturwissenschaften

Das Konzept des „Glaubens“ ist eine zentrale Grundlage von Polanyis Wissenschaftstheorie, und schon früh hat er sich explizit mit dem Verhältnis von Religion und Wissenschaft beschäftigt. Entsprechend wohlwollend ist seine Philosophie im Gespräch von Theologie und Naturwissenschaften aufgenommen worden. Seine deutschsprachige Rezeption blieb dabei bislang recht spärlich, während er in dem angelsächsischen Gespräch der Wissenschaften früh reiche Wirkung entfaltet und nahezu paradigmatische Bedeutung gewonnen hat. Die 2005 erschienene umfangreiche Polanyibiographie von William T. Scott und Martin X. Moleski, S.J. informiert auch über die Facetten von Polanyis eigenen Glauben. Sie stellt damit eine wesentliche Interpretationshilfe da, wie man eine Streitfrage der angelsächsischen Polanyi-Rezeption betreffs der Realität des Gegenstandes der Religion in seiner Philosophie beurteilen kann. Es ist davon auszugehen, dass er mit Tillich den Existenzbegriff in seiner Anwendung auf Gott abgelehnt hat und die Gelwick/Torrance-Prosch-Debatte, die um die Frage der unabhängigen Existenz Gottes in Polanyis Denken kreist, deswegen mehr oder weniger sinnlos ist.

Monte Carlo modeling of polarized light propagation: Stokes vs Jones - Part I

This bipartite comparative study aims at inspecting the similarities and differences between the Jones and Stokes–Mueller formalisms when modeling polarized light propagation with numerical simulations of the Monte Carlo type. In this first part, we review the theoretical concepts that concern light propagation and detection with both pure and partially/totally unpolarized states. The latter case involving fluctuations, or “depolarizing effects,” is of special interest here: Jones and Stokes–Mueller are equally apt to model such effects and are expected to yield identical results. In a second, ensuing paper, empirical evidence is provided by means of numerical experiments, using both formalisms.

Monte Carlo modeling of polarized light propagation: Stokes vs Jones - Part II

In this second part of our comparative study inspecting the (dis)similarities between “Stokes” and “Jones,” we present simulation results yielded by two independent Monte Carlo programs: (i) one developed in Bern with the Jones formalism and (ii) the other implemented in Ulm with the Stokes notation. The simulated polarimetric experiments involve suspensions of polystyrene spheres with varying size. Reflection and refraction at the sample/air interfaces are also considered. Both programs yield identical results when propagating pure polarization states, yet, with unpolarized illumination, second order statistical differences appear, thereby highlighting the pre-averaged nature of the Stokes parameters. This study serves as a validation for both programs and clarifies the misleading belief according to which “Jones cannot treat depolarizing effects.”

Helicobacter pylori Inhibits Dendritic Cell Maturation via Interleukin-10-Mediated Activation of the Signal Transducer and Activator of Transcription 3 Pathway.

Helicobacter pylori infects the human gastric mucosa causing a chronic infection that is the primary risk factor for gastric cancer development. Recent studies demonstrate that H. pylori promotes tolerogenic dendritic cell (DC) development indicating that this bacterium evades the host immune response. However, the signaling pathways involved in modulating DC activation during infection remain unclear. Here, we report that H. pylori infection activated the signal transducer and activator of transcription 3 (STAT3) pathway in murine bone marrow-derived DCs (BMDCs) and splenic DCs isolated ex vivo. Isogenic cagA-, cagE-, vacA- and urease-mutants exhibited levels of phosphoSTAT3 that were comparable to in the wild-type (WT) parent strain. H. pylori-infected BMDCs produced increased immunosuppressive IL-10, which activated STAT3 in an autocrine/paracrine fashion. Neutralization of IL-10 prevented H. pylori-mediated STAT3 activation in both BMDCs and splenic DCs. In addition, anti-IL-10 treatment of infected H. pylori-BMDCs was associated with increased CD86 and MHC II expression and enhanced proinflammatory IL-1β cytokine secretion. Finally, increased CD86 and MHC II expression was detected in H. pylori-infected STAT3 knockout DCs when compared to WT controls. Together, these results demonstrate that H. pylori infection induces IL-10 secretion in DCs, which activates STAT3, thereby modulating DC maturation and reducing IL-1β secretion. These findings identify a host molecular mechanism by which H. pylori can manipulate the innate immune response to potentially favor chronic infection and promote carcinogenesis. © 2014 S. Karger AG, Basel.

Der rettende Begleiter. Der Erzengel Michael ist mehr als nur der Engel, der mit dem Teufel kämpft

Ein Artikel über die Figur des Erzengels Michael und das theologische Engelsverständnis in einer kirchlichen Zeitschrift für ein allgemeines Publikum.

Molecular Classification of Ependymal Tumors across All CNS Compartments, Histopathological Grades, and Age Groups

Ependymal tumors across age groups are currently classified and graded solely by histopathology. It is, however, commonly accepted that this classification scheme has limited clinical utility based on its lack of reproducibility in predicting patients' outcome. We aimed at establishing a uniform molecular classification using DNA methylation profiling. Nine molecular subgroups were identified in a large cohort of 500 tumors, 3 in each anatomical compartment of the CNS, spine, posterior fossa, supratentorial. Two supratentorial subgroups are characterized by prototypic fusion genes involving RELA and YAP1, respectively. Regarding clinical associations, the molecular classification proposed herein outperforms the current histopathological classification and thus might serve as a basis for the next World Health Organization classification of CNS tumors.

Wissenschaft und Glauben bei Michael Polanyi

For Michael Polanyi, religion and science fight abreast to protect the occidental culture from totalitarian threat. Both are belief-based endeavors, Polanyi is convinced. While this is not surprising at all regarding religion, it is surely a provocation regarding science. The article tries to explore this original thought of Polanyi and to examine how it is rooted in his personal convictions and beliefs. Special emphasis is given to Polanyi’s critique of contemporary biology, as expressed in his article on “Science and Religion”, in some ways a response to Paul Tillich’s theology. Contemporary biology’s findings undermine exactly what Polanyi is fighting for, hence he is convinced that its findings are somewhat flawed. This should however not lead to the false conclusion that Polanyi had anything to do with creationism or would have favored Intelligent Design in our days.