A continent revealed - The European Geotraverse - Link to Atlas of compiled data

The continent of Europe has a complex geological history of successive tectonic events. Over several thousand million years these have formed the present day configuration of major tectonic provinces. A Continent Revealed unravels this history by presenting and interpreting the results of the European Geotraverse (EGT) a unique study of the continent of Europe and the first comprehensive cross section of continental lithosphere. This illustrated book has been put together by key workers in the EGT project. It uses the wealth of information yielded by the ten years of experiments, study centres and workshops to provide a concise and thought provoking account of the geological processes that created the European continent. It provides a summary of the European Geotraverse, and at the same time a starting point for further work.

Effects of ocean acidification on different life-cycle stages of the kelp Laminaria hyperborea (Phaeophyceae), link to supplementary data

Our objective for this study was to evaluate the influence of preindustrial and expected future atmospheric CO2 concentrations (280 µatm and 700 µatm pCO2, respectively) on different life-cycle stages of the kelp Laminaria hyperborea from Helgoland (Germany, North Sea). Zoospore germination, gametogenesis, vegetative growth, sorus formation and photosynthetic performance of vegetative and fertile tissue were examined. The contribution of external carbonic anhydrase (exCA) to C-supply for net-photosynthesis (net-PS) and the Chla- and phlorotannin content were investigated. Female gametogenesis and vegetative growth of sporophytes were significantly enhanced under the expected future pCO2. rETR(max) and net-PS of young vegetative sporophytes tended to increase performance at higher pCO2. The trend towards elevated net-PS vanished after inhibition of exCA. In vegetative sporophytes, phlorotannin content and Chla content were not significantly affected by pCO2.

Enhanced seasonal CO_2 exchange caused by amplified plant productivity in northern ecosystems, link to model results

Atmospheric monitoring of high northern latitudes (> 40°N) has shown an enhanced seasonal cycle of carbon dioxide (CO2) since the 1960s but the underlying mechanisms are not yet fully understood. The much stronger increase in high latitudes compared to low ones suggests that northern ecosystems are experiencing large changes in vegetation and carbon cycle dynamics. Here we show that the latitudinal gradient of the increasing CO2 amplitude is mainly driven by positive trends in photosynthetic carbon uptake caused by recent climate change and mediated by changing vegetation cover in northern ecosystems. Our results emphasize the importance of climate-vegetation-carbon cycle feedbacks at high latitudes, and indicate that during the last decades photosynthetic carbon uptake has reacted much more strongly to warming than carbon release processes.

Cross‐lingual link discovery in the Web of Data

Cross‐lingual link discovery in the Web of Data

YUCCA8 and YUCCA9 overexpression reveals a link between auxin signaling and lignification through the induction of ethylene biosynthesis.

Auxin is associated with the regulation of virtually every aspect of plant growth and development. Many previous genetic and biochemical studies revealed that, among the proposed routes for the production of auxin, the so-called indole-3-pyruvic acid (IPA) pathway is the main source for indole-3-acetic acid (IAA) in plants. The IPA pathway involves the action of 2 classes of enzymes, tryptophan-pyruvate aminotransferases (TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS 1(TAA1)/TRYPTOPHAN AMINOTRANSFERASE RELATED (TAR)) and flavin monooxygenases (YUCCA). Both enzyme classes appear to be encoded by small gene families in Arabidopsis consisting of 5 and 11 members, respectively. We recently showed that it is possible to induce transcript accumulation of 2 YUCCA genes, YUC8 and YUC9, by methyl jasmonate treatment. Both gene products were demonstrated to contribute to auxin biosynthesis in planta.1 Here we report that the overexpression of YUC8 as well as YUC9 led to strong lignification of plant aerial tissues. Furthermore, new evidence indicates that this abnormally strong secondary growth is linked to increased levels of ethylene production.

Exploring the link between sustainability reporting and sustainability management: a conceptual framework.

Sustainability managementand Sustainability Reporting (SR) practices have dramatically increased during the last two decades, raising important questions about the relationship between internal practices and external communication. Previous literature on SR has almost exclusively highlighted the role of institutional and stakeholder pressures in driving its adoption. However, as surveys among reporters also identify internal benefits of SR, its full role for company-level sustainability management remains unclear. In order to address this question, we develop a framework accounting for four SR configurations, stemming from different levels of relative importance of external and internal motives for SR. A multiple case study involving four large Spanish companies serves to illustrate the framework and to identify company-level factors that act both as enablers and barriers of SR internal relevance. We conclude that motivations for SR, along with such internal factors, decisively influence its contribution to sustainability management.

High-speed trains and tourists: what is the link? Evidence from the French and Spanish capitals

The objective of this paper is to analyse the factors influencing tourists? choice of a destination and the role of High Speed Rail (HSR) systems in this choice. The methodology proposed consists in analysing two capitals in Europe, i.e. Paris and Madrid where HSR services are important, to investigate the factors influencing holidaymakers in choosing these cities, and the role of HSR in this choice. The main outcome of this paper is to show that several factors influence the choice of a tourist, like the presence of architectural sites, the quality of promotion of the destination itself, the presence of events, and also HSR services. However we found that the HSR system has affected the choice of Paris and Madrid in a different way. Concerning the French case study, HSR is considered a real transport mode alternative among tourists, therefore HSR is chosen to reach Paris as well as for revisiting it. On the other hand, Madrid is chosen by tourists irrespective on the presence of HSR, while HSR is chosen for reaching cities close to Madrid. Data collected from the two surveys have been used for a further quantitative analysis. Models have been specified and calibrated to identify the factors influencing holidaymakers to revisit Paris and Madrid and the role of HSR in this choice has been highlighted.

Interaction of SP100 with HP1 proteins: A link between the promyelocytic leukemia-associated nuclear bodies and the chromatin compartment

The PML/SP100 nuclear bodies (NBs) were first described as discrete subnuclear structures containing the SP100 protein. Subsequently, they were shown to contain the PML protein which is part of the oncogenic PML-RARα hybrid produced by the t(15;17) chromosomal translocation characteristic of acute promyelocytic leukemia. Yet, the physiological role of these nuclear bodies remains unknown. Here, we show that SP100 binds to members of the heterochromatin protein 1 (HP1) families of non-histone chromosomal proteins. Further, we demonstrate that a naturally occurring splice variant of SP100, here called SP100-HMG, is a member of the high mobility group-1 (HMG-1) protein family and may thus possess DNA-binding potential. Both HP1 and SP100-HMG concentrate in the PML/SP100 NBs, and overexpression of SP100 leads to enhanced accumulation of endogenous HP1 in these structures. When bound to a promoter, SP100, SP100-HMG and HP1 behave as transcriptional repressors in transfected mammalian cells. These observations present molecular evidence for an association between the PML/SP100 NBs and the chromatin nuclear compartment. They support a model in which the NBs may play a role in certain aspects of chromatin dynamics.

A link density clustering algorithm based on automatically selecting density peaks for overlapping community detection

Peer reviewed

Thermus thermophilus: A link in evolution of the tRNA-dependent amino acid amidation pathways

Thermus thermophilus possesses an aspartyl-tRNA synthetase (AspRS2) able to aspartylate efficiently tRNAAsp and tRNAAsn. Aspartate mischarged on tRNAAsn then is converted into asparagine by an ω amidase that differs structurally from all known asparagine synthetases. However, aspartate is not misincorporated into proteins because the binding capacity of aminoacylated tRNAAsn to elongation factor Tu is only conferred by conversion of aspartate into asparagine. T. thermophilus additionally contains a second aspartyl-tRNA synthetase (AspRS1) able to aspartylate tRNAAsp and an asparaginyl-tRNA synthetase able to charge tRNAAsn with free asparagine, although the organism does not contain a tRNA-independent asparagine synthetase. In contrast to the duplicated pathway of tRNA asparaginylation, tRNA glutaminylation occurs in the thermophile via the usual pathway by using glutaminyl-tRNA synthetase and free glutamine synthesized by glutamine synthetase that is unique. T. thermophilus is able to ensure tRNA aminoacylation by alternative routes involving either the direct pathway or by conversion of amino acid mischarged on tRNA. These findings shed light on the interrelation between the tRNA-dependent and tRNA-independent pathways of amino acid amidation and on the processes involved in fidelity of the aminoacylation systems.

Link between light and fatty acid synthesis: Thioredoxin-linked reductive activation of plastidic acetyl-CoA carboxylase

Fatty acid synthesis in chloroplasts is regulated by light. The synthesis of malonyl-CoA, which is catalyzed by acetyl-CoA carboxylase (ACCase) and is the first committed step, is modulated by light/dark. Plants have ACCase in plastids and the cytosol. To determine the possible involvement of a redox cascade in light/dark modulation of ACCase, the effect of DTT, a known reductant of S-S bonds, was examined in vitro for the partially purified ACCase from pea plant. Only the plastidic ACCase was activated by DTT. This enzyme was activated in vitro more efficiently by reduced thioredoxin, which is a transducer of redox potential during illumination, than by DTT alone. Chloroplast thioredoxin-f activated the enzyme more efficiently than thioredoxin-m. The ACCase also was activated by thioredoxin reduced enzymatically with NADPH and NADP-thioredoxin reductase. These findings suggest that the reduction of ACCase is needed for activation of the enzyme, and a redox potential generated by photosynthesis is involved in its activation through thioredoxin as for enzymes of the reductive pentose phosphate cycle. The catalytic activity of ACCase was maximum at pH 8 and 2–5 mM Mg2+, indicating that light-produced changes in stromal pH and Mg2+ concentration modulate ACCase activity. These results suggest that light directly modulates a regulatory site of plastidic prokaryotic form of ACCase via a signal transduction pathway of a redox cascade and indirectly modulates its catalytic activity via stromal pH and Mg2+ concentration. A redox cascade is likely to link between light and fatty acid synthesis, resulting in coordination of fatty acid synthesis with photosynthesis.