155 research outputs found

    The impact of the Economic Crisis on the port of Duisburg 'Duisport'

    Get PDF
    Inland ports in the region of the “Blue Banana” in western Europe gain on importance. Beside several inland ports in the Rhine-Ruhr Area, the port of Duisburg, “Duisport- Group”, plays the most important role as being the biggest inland hub in Europe. Throughout the last decades, it has experienced the growth of inland freight distribution required an increase of flows. The port of Duisburg as an inland-hub is a more appropriate construct since it considers terminal activities as well as logistic activities taking place. As inland ports are fitting into regional economic geography by linking a region, the Rhine-Ruhr Area to global supply chains. However, since the ongoing economic crisis hit the world economy, also inland-hubs draw new visions and changes in their operating activities, as sea-hubs like Rotterdam. “Duisport´s” location is also special, due to the importance of coal and other bulk cargo, which plays a significant role in the Ruhr Area. The area is also special, for hundreds of firms operating, which are regulated by the harbour. Further, containerization is dominantly linked in the maritime and domestic transhipment, as other intermodal activities which might suffer by the economic crunch. This assignment evaluates the different functions of “Duisport-Group” and if they are capable to regulate the economic situation without suffering or how to overcome drops in demand for the nearby future. This analysis is based on the numbers of the annual reports from 2007 onwards and how the development directly after the crunch is characterized. There are significant changes in bulk and general cargo compared to the total revenue through the years. Finally, it is recommended that the “Duisport Group” is prepared well enough to foresee economical situations with a risk management system. That makes it possible to act early enough to overcome huge expenses and find prompt solutions. Lastly, an outlook on the operational side is given. It shows that especially in container transportation the potential for efficiency gains of port operations is tremendous

    A combinatorial TIR1/AFB–Aux/IAA co-receptor system for differential sensing of auxin

    Get PDF
    The plant hormone auxin regulates virtually every aspect of plant growth and development. Auxin acts by binding the F-box protein transport inhibitor response 1 (TIR1) and promotes the degradation of the AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) transcriptional repressors. Here we show that efficient auxin binding requires assembly of an auxin co-receptor complex consisting of TIR1 and an Aux/IAA protein. Heterologous experiments in yeast and quantitative IAA binding assays using purified proteins showed that different combinations of TIR1 and Aux/IAA proteins form co-receptor complexes with a wide range of auxin-binding affinities. Auxin affinity seems to be largely determined by the Aux/IAA. As there are 6 TIR1/AUXIN SIGNALING F-BOX proteins (AFBs) and 29 Aux/IAA proteins in Arabidopsis thaliana, combinatorial interactions may result in many co-receptors with distinct auxin-sensing properties. We also demonstrate that the AFB5–Aux/IAA co-receptor selectively binds the auxinic herbicide picloram. This co-receptor system broadens the effective concentration range of the hormone and may contribute to the complexity of auxin response

    Cytokinin acts through the auxin influx carrier AUX1 to regulate cell elongation in the root

    Get PDF
    Hormonal interactions are critical for plant development. In Arabidopsis, cytokinins inhibit root growth through effects on cell proliferation and cell elongation. Here we define key mechanistic elements in a regulatory network by which cytokinin inhibits root cell elongation in concert with the hormones auxin and ethylene. The auxin importer AUX1 functions as a positive regulator of cytokinin responses in the root, AUX1 mutants specifically affecting the ability of cytokinin to inhibit cell elongation but not cell proliferation. AUX1 is required for cytokinin-dependent changes of auxin activity in the lateral root cap associated with the control of cell elongation. Cytokinin regulates root cell elongation through ethylene-dependent and independent mechanisms, both hormonal signals converging on AUX1 as a regulatory hub. An autoregulatory circuit is identified involving the control of ARR10 and AUX1 expression by cytokinin and auxin, this circuit potentially functioning as an oscillator to integrate the effects of these two hormones. Taken together, our results uncover several regulatory circuits controlling interactions of cytokinin with auxin and ethylene, and support a model in which cytokinin regulates shootward auxin transport to control cell elongation and root growth

    BOLITA, an Arabidopsis AP2/ERF-like transcription factor that affects cell expansion and proliferation/differentiation pathways

    Get PDF
    The BOLITA (BOL) gene, an AP2/ERF transcription factor, was characterized with the help of an activation tag mutant and overexpression lines in Arabidopsis and tobacco. The leaf size of plants overexpressing BOL was smaller than wild type plants due to a reduction in both cell size and cell number. Moreover, severe overexpressors showed ectopic callus formation in roots. Accordingly, global gene expression analysis using the overexpression mutant reflected the alterations in cell proliferation, differentiation and growth through expression changes in RBR, CYCD, and TCP genes, as well as genes involved in cell expansion (i.e. expansins and the actin remodeling factor ADF5). Furthermore, the expression of hormone signaling (i.e. auxin and cytokinin), biosynthesis (i.e. ethylene and jasmonic acid) and regulatory genes was found to be perturbed in bol-D mutant leave

    Engaging diverse experts in a global environmental assessment: participation in the first work programme of IPBES and opportunities for improvement

    Get PDF
    The need for interdisciplinary expert groups from different regions of the world to be involved in the fields of sustainability science and environmental change research is increasingly recognised. The Intergovernmental Platform on Biodiversity and Ecosystem Services (IBPES) was established in 2012 as a science-policy interface and has gone beyond previous initiatives in its articulation of a clear commitment to inter- and transdisciplinary approaches that mandate a diversity of genders, disciplines and regional backgrounds within its expert groups. The first IPBES work programme, carried out between 2014 and 2018, has been supported by 17 expert groups, comprising over 1000 experts, who have been selected from over 2000 government and stakeholder nominations through formal procedures. In this paper, we present and critique the framework through which IPBES identifies and selects experts to participate in its processes. In addition, we synthesise and carry out a quantitative analysis on the expert nomination and selection data relating to the first assessment activities of IPBES. Identifying that the balance of regions, genders, disciplines and knowledge systems represented within these expert groups is still disproportionally dominated by male natural scientists from the Global North, the paper makes recommendations of how to better engage knowledge holders from different disciplines and diverse knowledge systems in future iterations of the IPBES work programme

    Biases in the production of knowledge on ecosystem services and poverty alleviation

    Get PDF
    Research into the relationship between ecosystem services and human well-being, including poverty alleviation, has blossomed. However, little is known about who has produced this knowledge, what collaborative patterns and institutional and funding conditions have underpinned it, or what implications these matters may have. To investigate the potential implications of such production for conservation science and practice, we address this by developing a social network analysis of the most prolific writers in the production of knowledge about ecosystem services and poverty alleviation. We show that 70% of these authors are men, most are trained in either the biological sciences or economics and almost none in the humanities. Eighty per cent of authors obtained their PhD from universities in the EU or the USA, and they are currently employed in these regions. The co-authorship network is strongly collaborative, without dominant authors, and with the top 30 most cited scholars being based in the USA and co-authoring frequently. These findings suggest, firstly, that the production of knowledge on ecosystem services and poverty alleviation research has the same geographical and gender biases that characterize knowledge production in other scientific areas and, secondly, that there is an expertise bias that also characterizes other environmental matters. This is despite the fact that the research field of ecosystem services and poverty alleviation, by its nature, requires a multidisciplinary lens. This could be overcome through promoting more extensive collaboration and knowledge co-production

    Interdependency of Brassinosteroid and Auxin Signaling in Arabidopsis

    Get PDF
    How growth regulators provoke context-specific signals is a fundamental question in developmental biology. In plants, both auxin and brassinosteroids (BRs) promote cell expansion, and it was thought that they activated this process through independent mechanisms. In this work, we describe a shared auxin:BR pathway required for seedling growth. Genetic, physiological, and genomic analyses demonstrate that response from one pathway requires the function of the other, and that this interdependence does not act at the level of hormone biosynthetic control. Increased auxin levels saturate the BR-stimulated growth response and greatly reduce BR effects on gene expression. Integration of these two pathways is downstream from BES1 and Aux/IAA proteins, the last known regulatory factors acting downstream of each hormone, and is likely to occur directly on the promoters of auxin:BR target genes. We have developed a new approach to identify potential regulatory elements acting in each hormone pathway, as well as in the shared auxin:BR pathway. We show that one element highly overrepresented in the promoters of auxin- and BR-induced genes is responsive to both hormones and requires BR biosynthesis for normal expression. This work fundamentally alters our view of BR and auxin signaling and describes a powerful new approach to identify regulatory elements required for response to specific stimuli

    Auxin Response Factor2 (ARF2) and Its Regulated Homeodomain Gene HB33 Mediate Abscisic Acid Response in Arabidopsis

    Get PDF
    The phytohormone abscisic acid (ABA) is an important regulator of plant development and response to environmental stresses. In this study, we identified two ABA overly sensitive mutant alleles in a gene encoding Auxin Response Factor2 (ARF2). The expression of ARF2 was induced by ABA treatment. The arf2 mutants showed enhanced ABA sensitivity in seed germination and primary root growth. In contrast, the primary root growth and seed germination of transgenic plants over-expressing ARF2 are less inhibited by ABA than that of the wild type. ARF2 negatively regulates the expression of a homeodomain gene HB33, the expression of which is reduced by ABA. Transgenic plants over-expressing HB33 are more sensitive, while transgenic plants reducing HB33 by RNAi are more resistant to ABA in the seed germination and primary root growth than the wild type. ABA treatment altered auxin distribution in the primary root tips and made the relative, but not absolute, auxin accumulation or auxin signal around quiescent centre cells and their surrounding columella stem cells to other cells stronger in arf2-101 than in the wild type. These results indicate that ARF2 and HB33 are novel regulators in the ABA signal pathway, which has crosstalk with auxin signal pathway in regulating plant growth
    corecore