2,553 research outputs found

    Transport Policy, Acceptance and the Media

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    The last two decades have seen a substantial change in the basic philosophy underlying European transportation policy. Due to the Commission's efforts and due to supporting jurisdiction by the European Court of Justice the dominant approach to transportation policy has become far more market oriented. This change of approach in transportation policy will only be successful and sustainable if the problem of acceptability will be solved. For researchers this entails that their perspective must change from the normative to the positive aspects of transportation policy-making. This paper reports work undertaken within research project TIPP (Transportation Institutions in the Policy Process) funded by the European Commission. In this work it has been attempted to develop a theoretical structure that merges the positive economic theory of regulation with cognitive psychology and traffic psychology. This theoretical structure offers a matrix of actors and factors that are seen to be essential for success or failure in the implementation of a certain measure of transport policy. Four case studies were carried out in order to check the plausibility of this approach. The case studies are the failure of the German Railway (Deutsche Bahn AG) to introduce a new tariff system in passenger transport in the period 2002-2003, the attempt to introduce a toll for HGVs in Germany, the failure to operate a private tolled motorway in Hungary (M1/M15), the failure to introduce a road-pricing system in the densely populated Randstad area in the Netherlands. --Transportation Policy,Europe,Common Transport Policy,Transport Regulation,Acceptability

    Fiscal Federalism and Financial Resources for Regional Development - Co-operative and Competitive Models: The International Experience - an Example for Russia?

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    In Western economies, the concrete design of fiscal federalism is determined by the status the federation grants to regionally comparable economic and social conditions, and to what extent this status is anchored in the constitution. If the political and social acceptance of regional differences is high, the significance of regional equalisation is low and vice versa. In the case of great regional differences fiscal equalisation could be overburdened by the task of reducing fiscal strength. Moreover, if the political and social acceptance is lacking, regional policy interventions of the federal level is appropriate to support the regional economic convergence rather than fiscal equalisation. However, in high-performing economies organized as federations, comparably weak institutions such as those in Russia are largely unknown. In this sense, international experience makes it clear that strong and well-designed institutional arrangements between the different governmental levels are an important precondition for a high-performing fiscal system. In other words, to take advantage of the potential efficiency gains offered by fiscal federalism, the vertical co-ordination of revenue and expenditure responsibilities between the different governmental levels should be clarified. Problems of destruction and enforcement should be eliminated and replaced by harmonization and co-operation.Fiscal federalism, Russia, regional policy, fiscal equalisation, tax policy

    Interpretable detection of novel human viruses from genome sequencing data

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    Viruses evolve extremely quickly, so reliable meth- ods for viral host prediction are necessary to safe- guard biosecurity and biosafety alike. Novel human- infecting viruses are difficult to detect with stan- dard bioinformatics workflows. Here, we predict whether a virus can infect humans directly from next- generation sequencing reads. We show that deep neural architectures significantly outperform both shallow machine learning and standard, homology- based algorithms, cutting the error rates in half and generalizing to taxonomic units distant from those presented during training. Further, we develop a suite of interpretability tools and show that it can be applied also to other models beyond the host pre- diction task. We propose a new approach for con- volutional filter visualization to disentangle the in- formation content of each nucleotide from its contri- bution to the final classification decision. Nucleotide- resolution maps of the learned associations between pathogen genomes and the infectious phenotype can be used to detect regions of interest in novel agents, for example, the SARS-CoV-2 coronavirus, unknown before it caused a COVID-19 pandemic in 2020. All methods presented here are implemented as easy- to-install packages not only enabling analysis of NGS datasets without requiring any deep learning skills, but also allowing advanced users to easily train and explain new models for genomics.Peer Reviewe

    Non-conservative Behavior of Dissolved Organic Matter and Trace Metals (Mn, Fe, Ba) Driven by Porewater Exchange in a Subtropical Mangrove-Estuary

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    Estuaries play a key role in controlling the land-ocean fluxes of dissolved organic matter (DOM), nutrients and trace metals. Here, we study how mangrove-fringed areas affect the molecular DOM and trace metal composition in a subtropical estuary. We combined molecular analysis of solid-phase extractable (SPE) DOM using ultrahigh-resolution mass spectrometry with organic and inorganic bulk parameter analyses in surface and porewater along the estuarine gradient of a mangrove-fringed estuary in Australia (Coffs Creek). Statistical analysis and mixing models demonstrate that the fluvial and mangrove-porewater derived DOM and inorganic chemical species were altered and/or removed by the estuarine filter before reaching the coastal ocean. The mangrove-fringed central estuary was a net source for dissolved Mn and Ba as well as total dissolved nitrogen (TDN) and dissolved organic carbon (DOC) to the tidal creek, likely due to the exchange of mangrove-porewater strongly enriched in these constituents. Dissolved Fe was removed from the water column, probably during the tidally driven circulation of creek water through the sulfidic mangrove sediments. In the mangrove-porewater dominated tidal creek, sulfur- and nitrogen-containing as well as aromatic DOM compounds were relatively enriched, whereas phosphorous-containing DOM was relatively depleted compared to non-mangrove fringed areas. In areas with intense mixing of estuarine and marine water masses we observed a strong decrease of these DOM compounds relative to values expected from conservative mixing, suggesting their removal by photodegradation and co-precipitation with particles such as Mn(hydr)oxides and/or as organometallic complexes, leading to more aliphatic DOM signatures at the creek-mouth. Tidally driven porewater exchange and surface water runoff from the mangroves had a stronger effect on the biogeochemical cycling in the estuary than the fluvial input during a dry compared to a wet season. Our study confirms that mangroves can significantly contribute to biogeochemical budgets of (sub)tropical estuaries

    Insights into the relationship between hydraulic safety, hydraulic efficiency and tree structural complexity from terrestrial laser scanning and fractal analysis

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    The potential of trees to adapt to drier and hotter climates will determine the future state of forests in the wake of a changing climate. Attributes connected to the hydraulic network are likely to determine a tree’s ability to endure drought. However, how a tree’s architectural attributes related to drought tolerance remains understudied. To fill this gap, we compared the structural complexity of 71 trees of 18 species obtained from terrestrial laser scanning (TLS) with key hydraulic thresholds. We used three measures of xylem safety, i.e., the water potential at 12%, 50%, and 88% loss of hydraulic conductance (P12, P50, P88) and specific hydraulic conductivity (Ks) to assess the trees’ drought tolerance. TLS data were used to generate 3D attributes of each tree and to construct quantitative structure models (QSMs) to characterize the branching patterns. Fractal analysis (box-dimension approach) was used to evaluate the overall structural complexity of the trees (Db) by integrating horizontal and vertical extent as well as internal branching patterns. Our findings revealed a significant relationship between the structural complexity (Db) and the three measures of xylem safety along with Ks. Tree species with low structural complexity developed embolism-resistant xylem at the cost of hydraulic efficiency. Our findings also revealed that the Db had a stronger and more significant relationship with branch hydraulic safety and efficiency compared to other structural attributes examined. We conclude that Db seems to be a robust descriptor of tree architecture that relates to important branch hydraulic properties of a tree

    Three-dimensional quantification of tree architecture from mobile laser scanning and geometry analysis

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    The structure and dynamics of a forest are defined by the architecture and growth patterns of its individual trees. In turn, tree architecture and growth result from the interplay between the genetic building plans and environmental factors. We set out to investigate whether (1) latitudinal adaptations of the crown shape occur due to characteristic solar elevation angles at a species’ origin, (2) architectural differences in trees are related to seed dispersal strategies, and (3) tree architecture relates to tree growth performance. We used mobile laser scanning (MLS) to scan 473 trees and generated three-dimensional data of each tree. Tree architectural complexity was then characterized by fractal analysis using the box-dimension approach along with a topological measure of the top heaviness of a tree. The tree species studied originated from various latitudinal ranges, but were grown in the same environmental settings in the arboretum. We found that trees originating from higher latitudes had significantly less top-heavy geometries than those from lower latitudes. Therefore, to a certain degree, the crown shape of tree species seems to be determined by their original habitat. We also found that tree species with wind-dispersed seeds had a higher structural complexity than those with animal-dispersed seeds (p < 0.001). Furthermore, tree architectural complexity was positively related to the growth performance of the trees (p < 0.001). We conclude that the use of 3D data from MLS in combination with geometrical analysis, including fractal analysis, is a promising tool to investigate tree architecture

    Molecular mechanism of topoisomerase poisoning by the peptide antibiotic albicidin

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    The peptide antibiotic albicidin is a DNA topoisomerase inhibitor with low-nanomolar bactericidal activity towards fluoroquinolone-resistant Gram-negative pathogens. However, its mode of action is poorly understood. We determined a 2.6 Å resolution cryoelectron microscopy structure of a ternary complex between Escherichia coli topoisomerase DNA gyrase, a 217 bp double-stranded DNA fragment and albicidin. Albicidin employs a dual binding mechanism where one end of the molecule obstructs the crucial gyrase dimer interface, while the other intercalates between the fragments of cleaved DNA substrate. Thus, albicidin efficiently locks DNA gyrase, preventing it from religating DNA and completing its catalytic cycle. Two additional structures of this trapped state were determined using synthetic albicidin analogues that demonstrate improved solubility, and activity against a range of gyrase variants and E. coli topoisomerase IV. The extraordinary promiscuity of the DNA-intercalating region of albicidins and their excellent performance against fluoroquinolone-resistant bacteria holds great promise for the development of last-resort antibiotics
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