First year of practical experiences of the new Arctic AWIPEV-COSYNA cabled Underwater Observatory in Kongsfjorden, Spitsbergen

A combined year-round assessment of selected oceanographic data and a macrobiotic community assess- ment was performed from October 2013 to November 2014 in the littoral zone of the Kongsfjorden polar fjord system on the western coast of Svalbard (Norway). State of the art remote controlled cabled underwater observatory technology was used for daily vertical profiles of temperature, salinity, and turbidity together with a stereo-optical assessment of the macrobiotic community, including fish. The results reveal a distinct seasonal cycle in total species abundances, with a significantly higher total abundance and species richness dur- ing the polar winter when no light is available underwater compared to the summer months when 24 h light is available. During the winter months, a temporally highly segmented community was observed with respect to species occurrence, with single species dominating the winter community for re- stricted times. In contrast, the summer community showed an overall lower total abundance as well as a significantly lower number of species. The study clearly demonstrates the high potential of cable connected remote controlled digital sampling devices, especially in remote areas, such as po- lar fjord systems, with harsh environmental conditions and limited accessibility. A smart combination of such new dig- ital “sampling” methods with classic sampling procedures can provide a possibility to significantly extend the sampling time and frequency, especially in remote and difficult to access areas. This can help to provide a sufficient data density and therefore statistical power for a sound scientific analysis without increasing the invasive sampling pressure in ecolog- ically sensitive environments

Effects of receptor clustering on ligand dissociation: Theory and simulations

Receptor-ligand binding is a critical first step in signal transduction and the duration of the interaction can impact signal generation. In mammalian cells, clustering of receptors may be facilitated by heterogeneous zones of lipids, known as lipid rafts. In vitro experiments show that disruption of rafts significantly alters the dissociation of fibroblast growth factor-2 (FGF-2) from heparan sulfate proteoglycans, co-receptors for FGF-2. In this paper, we develop a continuum stochastic formalism in order to (i) study how rebinding affects the dissociation of ligands from a planar substrate, and (ii) address the question of how receptor clustering influences ligand rebinding. We find that clusters reduce the effective dissociation rate dramatically when the clusters are dense and the overall surface density of receptors is low. The effect is much less pronounced in the case of high receptor density and shows non-monotonic behavior with time. These predictions are verified via lattice Monte Carlo simulations. Comparison with experimental results suggests that the theory does not capture the complete biological system. We speculate that additional co-operative mechanisms might be present in order to increase ligand retention, and present one possible ``internal diffusion'' model.Comment: Expanded text and added figures, revised version to appear in Biophys.

How Market Fragmentation Can Facilitate Collusion

Economists have recommended the fragmentation of capacities before regulated markets are liberalized because static oligopoly models imply that outcomes approximate perfect competition with a fragmented enough market structure. This intuition fails under collusion. When individual firms are capacity constrained relative to total demand, the fragmentation of capacity facilitates collusion and increases the highest sustainable collusive price. Collusive outcomes remain feasible even for arbitrarily fragmented capacity. These results can explain the finding in Sweeting (2007 , Economic Journal , 117, 654–685), that dramatic fragmentation of generation capacity in the English electricity industry did not reduce price cost margins.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/93695/1/j.1542-4774.2012.01083.x.pd

A Cartel Analysis of the German Labor Institutions and its Implications for Labor Market Reforms

In this paper we apply standard cartel theory to identify the major institutional stabilizers of Germany?s area tariff system of collective bargaining between a single industry union and the industry?s employers association. Our cartel analysis allows us to demonstrate that recent labor policy reforms that intend to make labor markets more ?flexible? further serve to stabilize the labor cartel while other pro-competitive proposals have failed. We argue that the pro-competitive recommendations failed exactly because of their destabilizing effects on insiders? incentives to stay in the labor cartel. We propose regulatory measures for injecting competition into Germany?s labor markets that focus on the creation of new options for firms and workers outside the existing area tariff system; in particular, by liberalizing existing barriers for the establishment of a fully tariff-enabled union. Such an endeavor must go hand in hand with the institutionalization of a competition policy framework for labor market disputes as any destabilizing policy inevitably provokes counter measures of the incumbent labor cartel so as to protect their dominance vis-?-vis outsider competition

Neuro-cognitive mechanisms of conscious and unconscious visual perception: From a plethora of phenomena to general principles

Psychological and neuroscience approaches have promoted much progress in elucidating the cognitive and neural mechanisms that underlie phenomenal visual awareness during the last decades. In this article, we provide an overview of the latest research investigating important phenomena in conscious and unconscious vision. We identify general principles to characterize conscious and unconscious visual perception, which may serve as important building blocks for a unified model to explain the plethora of findings. We argue that in particular the integration of principles from both conscious and unconscious vision is advantageous and provides critical constraints for developing adequate theoretical models. Based on the principles identified in our review, we outline essential components of a unified model of conscious and unconscious visual perception. We propose that awareness refers to consolidated visual representations, which are accessible to the entire brain and therefore globally available. However, visual awareness not only depends on consolidation within the visual system, but is additionally the result of a post-sensory gating process, which is mediated by higher-level cognitive control mechanisms. We further propose that amplification of visual representations by attentional sensitization is not exclusive to the domain of conscious perception, but also applies to visual stimuli, which remain unconscious. Conscious and unconscious processing modes are highly interdependent with influences in both directions. We therefore argue that exactly this interdependence renders a unified model of conscious and unconscious visual perception valuable. Computational modeling jointly with focused experimental research could lead to a better understanding of the plethora of empirical phenomena in consciousness research

Modern Industrial Economics and Competition Policy: Open Problems and Possible Limits

Naturally, competition policy is based on competition economics made applicable in terms of law and its enforcement. Within the different branches of competition economics, modern industrial economics, or more precisely gametheoretic oligopoly theory, has become the dominating paradigm both in the U.S. (since the 1990s Post-Chicago movement) and in the EU (so-called more economic approach in the 2000s). This contribution reviews the state of the art in antitrust-oriented modern industrial economics and, in particular, critically discusses open questions and possible limits of basing antitrust on modern industrial economics. In doing so, it provides some hints how to escape current enforcement problems in industrial economics-based competition policy on both sides of the Atlantic. In particular, the paper advocates a change of the way modern industrial economics is used in competition policy: instead of more and more case-by-cases analyses, the insights from modern industrial economics should be used to design better competition rules

Stroke genetics informs drug discovery and risk prediction across ancestries

Previous genome-wide association studies (GWASs) of stroke — the second leading cause of death worldwide — were conducted predominantly in populations of European ancestry1,2. Here, in cross-ancestry GWAS meta-analyses of 110,182 patients who have had a stroke (five ancestries, 33% non-European) and 1,503,898 control individuals, we identify association signals for stroke and its subtypes at 89 (61 new) independent loci: 60 in primary inverse-variance-weighted analyses and 29 in secondary meta-regression and multitrait analyses. On the basis of internal cross-ancestry validation and an independent follow-up in 89,084 additional cases of stroke (30% non-European) and 1,013,843 control individuals, 87% of the primary stroke risk loci and 60% of the secondary stroke risk loci were replicated (P < 0.05). Effect sizes were highly correlated across ancestries. Cross-ancestry fine-mapping, in silico mutagenesis analysis3, and transcriptome-wide and proteome-wide association analyses revealed putative causal genes (such as SH3PXD2A and FURIN) and variants (such as at GRK5 and NOS3). Using a three-pronged approach4, we provide genetic evidence for putative drug effects, highlighting F11, KLKB1, PROC, GP1BA, LAMC2 and VCAM1 as possible targets, with drugs already under investigation for stroke for F11 and PROC. A polygenic score integrating cross-ancestry and ancestry-specific stroke GWASs with vascular-risk factor GWASs (integrative polygenic scores) strongly predicted ischaemic stroke in populations of European, East Asian and African ancestry5. Stroke genetic risk scores were predictive of ischaemic stroke independent of clinical risk factors in 52,600 clinical-trial participants with cardiometabolic disease. Our results provide insights to inform biology, reveal potential drug targets and derive genetic risk prediction tools across ancestries

Fish, macroinvertebrates and physical oceanography including CTD profiling data from the shallow water area of Kongsfjord, Svalbard from 2013 to 2014

A combined year round assessment of selected oceanographic data and a macrobiotic community assessment was performed from October 2013 to November 2014 in the littoral zone of the polar fjord systems Kongsfjorden on the west coast of Svalbard (Norway). A state of the art remote controlled cabled underwater observatory technology was used for daily vertical profiles of temperature, salinity and turbidity together with a stereo-optical assessment of the macrobiotic community, including fish. The results reveal a distinct seasonal cycle in total species abundances with a significantly higher total abundance and species richness during the polar winter when no light is available under water compared to the summer months when 24-h light is available. During the winter months, a temporally highly segmented community was observed with respect to species occurrence with single species dominating the winter community for restricted times. In contrast, the summer community showed an overall lower total abundance, as well as a significantly lower number of species. The study clearly demonstrates the high potential of cable connected remote controlled digital sampling devices, especially in remote areas, such as the polar fjord systems, with harsh environmental conditions and limited accessibility. A smart combination of such new digital ?sampling? methods with classic sampling procedures can provide a possibility to significantly extend the sampling time and frequency especially in remote and difficult to access areas. This can help to provide a sufficient data density and therefore statistical power for a sound scientific analysis without increasing the invasive sampling pressure in ecologically sensitive environments

Hydrographical time series data of the littoral zone of Kongsfjorden, Svalbard 2015

The dataset contains temperature, salinity, oxygen saturation, chlorophyll A and turbidity data from the AWIPEV underwater observatory from the year 2015 in a temporal resolution of 1 hour. The cabled observatory is located in 12m water depth and comprises single or multiple sensors for a specific parameter (see https://www.awi.de/en/science/biosciences/shelf-sea-system-ecology/main-research-focus/cosyna/underwater-node-spitsbergen.html) For a detailed description of the data see associated metadatafile "metadata_svulobs_2015_hydrography.pdf"