Formation and Detectability of Terrestrial Planets Around Alpha Centauri B

We simulate the formation of planetary systems around Alpha Centauri B. The N-body accretionary evolution of a 1/r disk populated with 400-900 lunar-mass protoplanets is followed for 200 Myr. All simulations lead to the formation of multiple-planet systems with at least one planet in the 1-2 MEarth mass range at 0.5-1.5 AU. We examine the detectability of our simulated planetary systems by generating synthetic radial velocity observations including noise based on the radial velocity residuals to the recently published three planet fit to the nearby K0V star HD 69830. Using these synthetic observations, we find that we can reliably detect a 1.8 MEarth planet in the habitable zone of Alpha Centauri B after only three years of high cadence observations. We also find that the planet is detectable even if the radial velocity precision is 3 m/s, as long as the noise spectrum is white. Our results show that the greatest uncertainty in our ability to detect rocky planets in the Alpha Centauri system is the unknown magnitude of ultra-low frequency stellar noise.Comment: 17 pages, 5 figures; accepted for publication in the Astrophysical Journa

Implementing Green Infrastructure for the Spatial Planning of Peri-Urban Areas in Geneva, Switzerland

The concept of green infrastructure (GI) seeks to identify and prioritize areas of high ecological value for wildlife and people, to improve the integration of natural values in landscape planning decisions. In 2018, the canton of Geneva, Switzerland, established a roadmap for biodiversity conservation, which includes the operationalization of GI covering 30% of the territory by 2030. In this paper, we demonstrate a GI mapping framework in the canton of Geneva. Our approach is based on the combined assessment of three 'pillars', namely species' distribution, landscape structure and connectivity, and ecosystem services, to optimize the allocation of conservation actions using the spatial prioritization software, Zonation. The identified priority conservation areas closely overlap existing natural reserves. Including the three pillars in the landscape prioritization should also improve adhesion to the GI idea, without undermining the protection of threatened species. With regards to land use planning, public and private land parcels with high values for GI may require specific incentives to maintain their desirable characteristics, as they are more likely to be degraded than areas with more building restrictions. Visualizing priority conservation areas in a spatially explicit manner will support decision-makers in Geneva to optimally allocate limited resources for ecosystem preservation.Peer reviewe

Inducing behavioural change in society through communication and education in sustainable manufacturing

The United Nations considers the mobilization of the broad public to be the essential requirement for achieving a shift towards a more sustainable development. Science can play a vital role in Education for Sustainable Development (ESD) by contributing to ESD-related research and development on the one hand, and by becoming active awareness raisers themselves in education and multiplier networks. Specifically, the use of special Learnstruments, and investment inOpen Educationformats among other educational tools, may pave the way for accelerated apprehension and appreciation of sustainable manufacturing topics among the greater populace

Multiple roles of GluN2B-containing NMDA receptors in synaptic plasticity in juvenile hippocampus

AbstractIn the CA1 area of the hippocampus N-methyl-d-aspartate receptors (NMDARs) mediate the induction of long-term depression (LTD), short-term potentiation (STP) and long-term potentiation (LTP). All of these forms of synaptic plasticity can be readily studied in juvenile hippocampal slices but the involvement of particular NMDAR subunits in the induction of these different forms of synaptic plasticity is currently unclear. Here, using NVP-AAM077, Ro 25-6981 and UBP145 to target GluN2A-, 2B- and 2D-containing NMDARs respectively, we show that GluN2B-containing NMDARs (GluN2B) are involved in the induction of LTD, STP and LTP in slices prepared from P14 rat hippocampus. A concentration of Ro (1 μM) that selectively blocks GluN2B-containing diheteromers is able to block LTD. It also inhibits a component of STP without affecting LTP. A higher concentration of Ro (10 μM), that also inhibits GluN2A/B triheteromers, blocks LTP. UBP145 selectively inhibits the Ro-sensitive component of STP whereas NVP inhibits LTP. These data are consistent with a role of GluN2B diheretomers in LTD, a role of both GluN2B- and GluN2D- containing NMDARs in STP and a role of GluN2A/B triheteromers in LTP.This article is part of the Special Issue entitled ‘Ionotropic glutamate receptors’

Engineering of Insulin Receptor Isoform-Selective Insulin Analogues

BACKGROUND: The insulin receptor (IR) exists in two isoforms, A and B, and the isoform expression pattern is tissue-specific. The C-terminus of the insulin B chain is important for receptor binding and has been shown to contact the IR just adjacent to the region where the A and B isoforms differ. The aim of this study was to investigate the importance of the C-terminus of the B chain in IR isoform binding in order to explore the possibility of engineering tissue-specific/liver-specific insulin analogues. METHODOLOGY/PRINCIPAL FINDINGS: Insulin analogue libraries were constructed by total amino acid scanning mutagenesis. The relative binding affinities for the A and B isoform of the IR were determined by competition assays using scintillation proximity assay technology. Structural information was obtained by X-ray crystallography. Introduction of B25A or B25N mutations resulted in analogues with a 2-fold preference for the B compared to the A isoform, whereas the opposite was observed with a B25Y substitution. An acidic amino acid residue at position B27 caused an additional 2-fold selective increase in affinity for the receptor B isoform for analogues bearing a B25N mutation. Furthermore, the combination of B25H with either B27D or B27E also resulted in B isoform-preferential analogues (2-fold preference) even though the corresponding single mutation analogues displayed no differences in relative isoform binding affinity. CONCLUSIONS/SIGNIFICANCE: We have discovered a new class of IR isoform-selective insulin analogues with 2-4-fold differences in relative binding affinities for either the A or the B isoform of the IR compared to human insulin. Our results demonstrate that a mutation at position B25 alone or in combination with a mutation at position B27 in the insulin molecule confers IR isoform selectivity. Isoform-preferential analogues may provide new opportunities for developing insulin analogues with improved clinical benefits

CD11b+, Ly6G+ Cells Produce Type I Interferon and Exhibit Tissue Protective Properties Following Peripheral Virus Infection

The goal of the innate immune system is containment of a pathogen at the site of infection prior to the initiation of an effective adaptive immune response. However, effector mechanisms must be kept in check to combat the pathogen while simultaneously limiting undesirable destruction of tissue resulting from these actions. Here we demonstrate that innate immune effector cells contain a peripheral poxvirus infection, preventing systemic spread of the virus. These innate immune effector cells are comprised primarily of CD11b+Ly6C+Ly6G- monocytes that accumulate initially at the site of infection, and are then supplemented and eventually replaced by CD11b+Ly6C+Ly6G+ cells. The phenotype of the CD11b+Ly6C+Ly6G+ cells resembles neutrophils, but the infiltration of neutrophils typically occurs prior to, rather than following, accumulation of monocytes. Indeed, it appears that the CD11b+Ly6C+Ly6G+ cells that infiltrated the site of VACV infection in the ear are phenotypically distinct from the classical description of both neutrophils and monocyte/macrophages. We found that CD11b+Ly6C+Ly6G+ cells produce Type I interferons and large quantities of reactive oxygen species. We also observed that depletion of Ly6G+ cells results in a dramatic increase in tissue damage at the site of infection. Tissue damage is also increased in the absence of reactive oxygen species, although reactive oxygen species are typically thought to be damaging to tissue rather than protective. These data indicate the existence of a specialized population of CD11b+Ly6C+Ly6G+ cells that infiltrates a site of virus infection late and protects the infected tissue from immune-mediated damage via production of reactive oxygen species. Regulation of the action of this population of cells may provide an intervention to prevent innate immune-mediated tissue destruction