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Item does not contain fulltext, Proton-pumping NADH:ubiquinone oxidoreductase (complex I) is the largest and most complicated enzyme of the respiratory chain. Fourteen central subunits represent the minimal form of complex I and can be assigned to functional modules for NADH oxidation, ubiquinone reduction, and proton pumping. In addition, the mitochondrial enzyme comprises some 30 accessory subunits surrounding the central subunits that are not directly associated with energy conservation. Complex I is known to release deleterious oxygen radicals (ROS) and its dysfunction has been linked to a number of hereditary and degenerative diseases. We here review recent progress in structure determination, and in understanding the role of accessory subunits and functional analysis of mitochondrial complex I. For the central subunits, structures provide insight into the arrangement of functional modules including the substrate binding sites, redox-centers and putative proton channels and pump sites. Only for two of the accessory subunits, detailed structures are available. Nevertheless, many of them could be localized in the overall structure of complex I, but most of these assignments have to be considered tentative. Strikingly, redox reactions and proton pumping machinery are spatially completely separated and the site of reduction for the hydrophobic substrate ubiquinone is found deeply buried in the hydrophilic domain of the complex. The X-ray structure of complex I from Yarrowia lipolytica provides clues supporting the previously proposed two-state stabilization change mechanism, in which ubiquinone redox chemistry induces conformational states and thereby drives proton pumping. The same structural rearrangements may explain the active/deactive transition of complex I implying an integrated mechanistic model for energy conversion and regulation. This article is part of a Special Issue entitled Respiratory complex I, edited by Volker Zickermann and Ulrich Brandt.

Earth is home to a remarkable diversity of plant forms and life histories, yet comparatively few essential trait combinations have proved evolutionarily viable in today € s terrestrial biosphere. By analysing worldwide variation in six major traits critical to growth, survival and reproduction within the largest sample of vascular plant species ever compiled, we found that occupancy of six-dimensional trait space is strongly concentrated, indicating coordination and trade-offs. Three-quarters of trait variation is captured in a two-dimensional global spectrum of plant form and function. One major dimension within this plane reflects the size of whole plants and their parts; the other represents the leaf economics spectrum, which balances leaf construction costs against growth potential. The global plant trait spectrum provides a backdrop for elucidating constraints on evolution, for functionally qualifying species and ecosystems, and for improving models that predict future vegetation based on continuous variation in plant form and function.

Im Rahmen des GEWISS-Bausteinprogramms wurde das Grünbuch für eine Citizen Science-Strategie 2020 für Deutschland zusammen mit über 700 an Citizen Science interessierten Personen aus mehr als 350 Organisationen und Einzelpersonen erarbeitet.Bürgerschaftliches Engagement spielt auch in der Forschung eine immer wichtigere Rolle und kann ein Weg der Teilhabe für die verschiedensten Gruppen in unserer stark wissenschaftsbasierten Gesellschaft sein. Aktuell wird die Beteiligung von Bürgerinnen und Bürgern an wissenschaftlichen Prozessen wesentlich unter dem Stichwort „Citizen Science“ diskutiert. Über die wissenschaftlichen Erkenntnisseund Daten hinaus kann Citizen Science einen Mehrwert für die Gesellschaft erzielen: Menschen erweitern ihr Wissen über Natur, Technik, Geschichte – und lernen, wie Wissenschaft funktioniert. Sie können Daten und Ergebnisse aus der Wissenschaft besser einschätzen und auch die Grenzen wissenschaftlicher Methoden und Erkenntnisse nachvollziehen. Unabdingbar ist, dass bei allen Citizen-Science-Projektender wissenschaftliche Erkenntnisgewinn im Fokus bleibt.Dieses Grünbuch Citizen-Science-Strategie 2020 für Deutschland stellt das Verständnis, die Bedarfe und Potenziale von Citizen Science in Deutschland vor. Es reflektiert, welcher Mehrwert in den verschiedenen gesellschaftlichen Bereichen entstehen kann und wo noch nicht ausgeschöpftes Potenzial vorhanden ist. Zu deren Verwirklichung werden konkrete Vorschläge für Handlungsoptionen und Maßnahmen entwickelt, die der Stärkung von Citizen Science in Deutschland dienen und langfristig Kapazitäten für die erfolgreiche Durchführung von Citizen Science freisetzen können.An der Diskussion um die Bedeutung von Citizen Science, aber auch über Herausforderungen und Hemmnisse, haben sich viele Personen mit unterschiedlichen Hintergründen im Rahmen verschiedener Veranstaltungen und der Online-Konsultation der Strategie beteiligt. Ihnen allen möchten wir unseren Dank für die unterstützenden, kritischen und

Civic engagement plays an increasingly important role, not only in society but also in research, as one avenue for different actors to actively participate in our strongly science-based society. Currently, citizen participation in scientific processes is dis- cussed widely under the heading of “Citizen Science”. Beyond advancing scientific find- ings and large scale data provision, Citizen Science can generate significant added value for society: people can enhance their scientific literacy in fields such as nature, technology and history – and learn how science works. They are better equipped to assess scientific data and results and to understand the limitations of scientific methods and findings. The overarching focus for all Citizen Science projects is the gaining of scientific knowledge for both science and society.This Green Paper Citizen Science Strategy 2020 for Germany presents the under- standing, the requirements and the potential of Citizen Science in Germany. It re- flects on the multiple benefits of Citizen Science for different sectors of society and on options and opportunities to develop the methodology and approach. In order to real- ise this potential, the Green Paper develops 10 potential fields of action to strengthen Citizen Science in Germany and to build capacities for the successful implementation of Citizen Science programmes.During the GEWISS events, and through the online and written consultation on the Citizen Science Strategy 2020 for Germany, many participants with different back- grounds joined the discussions on the significance of Citizen Science, the challenges as well as opportunities. We are extremely grateful for all their supportive, critical and inspiring  contributions.We hope to maintain an open and transparent dialogue with all stakeholders, also in the future. This should focus on demonstrating and evaluating citizen science experiences in practice and developing success criteria to support the initiators and prom

Ecological research produces a tremendous amount of data, but the diversity in scales and topics covered and the ways in which studies are carried out result in large numbers of small, idiosyncratic data sets using heterogeneous terminologies. Such heterogeneity can be attributed, in part, to a lack of standards for acquiring, organizing and describing data. Here, we propose a terminological resource, a Thesaurus Of Plant characteristics (TOP), whose aim is to harmonize and formalize concepts for plant characteristics widely used in ecology.TOP concentrates on two types of plant characteristics: traits and environmental associations. It builds on previous initiatives for several aspects: (i) characteristics are designed following the entity-quality (EQ) model (a characteristic is modelled as the ‘Quality’ of an ‘Entity’ ) used in the context of Open Biological Ontologies; (ii) whenever possible, the Entities and Qualities are taken from existing terminology standards, mainly the Plant Ontology (PO) and Phenotypic Quality Ontology (PATO) ontologies; and (iii) whenever a characteristic already has a definition, if appropriate, it is reused and referenced. The development of TOP, which complies with semantic web principles, was carried out through the involvement of experts from both the ecology and the semantics research communities. Regular updates of TOP are planned, based on community feedback and involvement.TOP provides names, definitions, units, synonyms and related terms for about 850 plant characteristics. TOP is available online (www.top-thesaurus.org), and can be browsed using an alphabetical list of characteristics, a hierarchical tree of characteristics, a faceted and a free-text search, and through an Application Programming Interface.Synthesis. Harmonizing definitions of concepts, as proposed by TOP, forms the basis for better integration of data across heterogeneous data sets and terminologies, thereby increasing the p

Higher plant diversity reduces nitrate leaching by complementary resource use, while its relation to leaching of other N species is unclear. We determined the effects of plant species richness, functional group richness, and the presence of specific functional groups on ammonium, dissolved organic N (DON), and total dissolved N (TDN) leaching from grassland in the first 4 years after conversion from fertilized arable land to unfertilized grassland. On 62 experimental plots in Jena, Germany, with 1–60 plant species and 1–4 functional groups (legumes, grasses, tall herbs, small herbs), nitrate, ammonium, and TDN concentrations in soil solution (0–0.3 m soil layer) were measured fortnightly during 4 years. DON concentrations were calculated by subtracting inorganic N from TDN. Nitrogen concentrations were multiplied with modeled downward water fluxes to obtain N leaching. DON leaching contributed most to TDN leaching (64 ± SD 4% of TDN). Ammonium leaching was unaffected by plant diversity. Increasing species richness decreased DON leaching in the fourth year. We attribute this finding to enhanced use of DON as a C and N source and enhanced mineralization of DON by soil microorganisms. An increase of species richness decreased TDN leaching likely driven by the complementary use of nitrate by diverse mixtures. Legumes increased DON and TDN leaching likely because of their N2-fixing ability and higher litter production. Grasses decreased TDN leaching because of more exhaustive use of nitrate and water. Our results demonstrate that increasing plant species richness decreases leaching of DON and TDN.

The success of remote sensing approaches to assess tree species diversity in a heterogeneously mixed forest stand depends on the availability of both appropriate data and suitable classification algorithms. To separate the high number of in total ten broadleaf tree species in a small structured floodplain forest, the Leipzig Riverside Forest, we introduce a majority based classification approach for Discriminant Analysis based on Partial Least Squares (PLS-DA), which was tested against Random Forest (RF) and Support Vector Machines (SVM). The classifier performance was tested on different sets of airborne hyperspectral image data (AISA DUAL) that were acquired on single dates in August and September and also stacked to a composite product. Shadowed gaps and shadowed crown parts were eliminated via spectral mixture analysis (SMA) prior to the pixel-based classification. Training and validation sets were defined spectrally with the conditioned Latin hypercube method as a stratified random sampling procedure. In the validation, PLS-DA consistently outperformed the RF and SVM approaches on all datasets. The additional use of spectral variable selection (CARS, “competitive adaptive reweighted sampling”) combined with PLS-DA further improved classification accuracies. Up to 78.4% overall accuracy was achieved for the stacked dataset. The image recorded in August provided slightly higher accuracies than the September image, regardless of the applied classifier.

Plant diversity enhances many ecosystem functions, including root biomass production, which drives soil carbon input. Although root decomposition accounts for a large proportion of carbon input for soil, little is known about plant diversity effect on this process. Plant diversity may affect root decomposition in two non-exclusive ways: by providing roots of different substrate quality (e.g. root chemistry) and/or by altering the soil environment (e.g. microclimate).To disentangle these two pathways, we conducted three decomposition experiments using a litter-bag approach in a grassland biodiversity experiment. We hypothesized that: (i) plant species richness negatively affects substrate quality (indicated by increased C:N ratios), which we tested by decomposing roots collected from each experimental plot in one common plot; (ii) plant species richness positively affects soil environment (indicated by increased soil water content), which we tested by decomposing standardized roots in all experimental plots; (iii) the overall effect of plant species richness on root decomposition, due to the contrast between quality and environmental effects, is neutral, which we tested by decomposing community roots in their ‘home’ plots.Plant species richness negatively affected root decomposition in all three experiments. The negative effect of plant species richness on substrate quality was largely explained by increased root C:N ratios along the diversity gradient. Functional group presence explained more variance in substrate quality than species richness. Here, the presence of grasses negatively affected substrate quality and root C:N ratios, while the presence of legumes and small herbs had positive effects. Plant species richness had a negative effect on soil environment despite its positive effect on soil water content which is known to stimulate decomposition. We argue that – instead of soil water content – a combined effect of soil temperature and seasonality might drive

Im Rahmen des GEWISS-Bausteinprogramms wurde das Grünbuch für eine Citizen Science-Strategie 2020 für Deutschland zusammen mit über 700 an Citizen Science interessierten Personen aus mehr als 350 Organisationen und Einzelpersonen erarbeitet.Bürgerschaftliches Engagement spielt auch in der Forschung eine immer wichtigere Rolle und kann ein Weg der Teilhabe für die verschiedensten Gruppen in unserer stark wissenschaftsbasierten Gesellschaft sein. Aktuell wird die Beteiligung von Bürgerinnen und Bürgern an wissenschaftlichen Prozessen wesentlich unter dem Stichwort „Citizen Science“ diskutiert. Über die wissenschaftlichen Erkenntnisseund Daten hinaus kann Citizen Science einen Mehrwert für die Gesellschaft erzielen: Menschen erweitern ihr Wissen über Natur, Technik, Geschichte – und lernen, wie Wissenschaft funktioniert. Sie können Daten und Ergebnisse aus der Wissenschaft besser einschätzen und auch die Grenzen wissenschaftlicher Methoden und Erkenntnisse nachvollziehen. Unabdingbar ist, dass bei allen Citizen-Science-Projektender wissenschaftliche Erkenntnisgewinn im Fokus bleibt.Dieses Grünbuch Citizen-Science-Strategie 2020 für Deutschland stellt das Verständnis, die Bedarfe und Potenziale von Citizen Science in Deutschland vor. Es reflektiert, welcher Mehrwert in den verschiedenen gesellschaftlichen Bereichen entstehen kann und wo noch nicht ausgeschöpftes Potenzial vorhanden ist. Zu deren Verwirklichung werden konkrete Vorschläge für Handlungsoptionen und Maßnahmen entwickelt, die der Stärkung von Citizen Science in Deutschland dienen und langfristig Kapazitäten für die erfolgreiche Durchführung von Citizen Science freisetzen können.An der Diskussion um die Bedeutung von Citizen Science, aber auch über Herausforderungen und Hemmnisse, haben sich viele Personen mit unterschiedlichen Hintergründen im Rahmen verschiedener Veranstaltungen und der Online-Konsultation der Strategie beteiligt. Ihnen allen möchten wir unseren Dank für die unterstützenden, kritischen und

Civic engagement plays an increasingly important role, not only in society but also in research, as one avenue for different actors to actively participate in our strongly science-based society. Currently, citizen participation in scientific processes is dis- cussed widely under the heading of “Citizen Science”. Beyond advancing scientific find- ings and large scale data provision, Citizen Science can generate significant added value for society: people can enhance their scientific literacy in fields such as nature, technology and history – and learn how science works. They are better equipped to assess scientific data and results and to understand the limitations of scientific methods and findings. The overarching focus for all Citizen Science projects is the gaining of scientific knowledge for both science and society.This Green Paper Citizen Science Strategy 2020 for Germany presents the under- standing, the requirements and the potential of Citizen Science in Germany. It re- flects on the multiple benefits of Citizen Science for different sectors of society and on options and opportunities to develop the methodology and approach. In order to real- ise this potential, the Green Paper develops 10 potential fields of action to strengthen Citizen Science in Germany and to build capacities for the successful implementation of Citizen Science programmes.During the GEWISS events, and through the online and written consultation on the Citizen Science Strategy 2020 for Germany, many participants with different back- grounds joined the discussions on the significance of Citizen Science, the challenges as well as opportunities. We are extremely grateful for all their supportive, critical and inspiring  contributions.We hope to maintain an open and transparent dialogue with all stakeholders, also in the future. This should focus on demonstrating and evaluating citizen science experiences in practice and developing success criteria to support the initiators and prom

This data set contains mass loss of community roots decomposing in the common plot in the Jena experiment in 2014. The Metadata contains the Dataset ID in the Jena Experiment database and detailed information of column: 'plotcode' is plot ID in the Jena Experiment; 'bag_ID' is the ID for litter bags within each decomposition experiment; 'root_type' is the type of roots in the litter bags where plot coded for community roots, lolium coded for standardized roots; 'site' is the location of where decomposition happened; 'sector' is the subplots in common plot; 'mass_initial' is root mass in the litter bags before buried in the field and handling loss is seduced already; 'mass_remain' is root mass in the litter bags at each retrieval; 'date_in' is the exact dates when the litter bags were buried. In the form of DD-MM-YY; 'date_out' is the exact dates when the litter bags were retrieved. In the form of DD-MM-YY; 'actual_decomptime' is the exact days litter bags were in the field; 'massloss' is actual mass loss =100 - mass_remain/mass_initial*100; 'std_decomptime' is standardized days litter bags were in the field; 'std_massloss' is stadardized mass loss = massloss/actual_decomp.time*std_decomp.time.

Item does not contain fulltext

Item does not contain fulltext, Proton-pumping complex I of the mitochondrial respiratory chain is among the largest and most complicated membrane protein complexes. The enzyme contributes substantially to oxidative energy conversion in eukaryotic cells. Its malfunctions are implicated in many hereditary and degenerative disorders. We report the x-ray structure of mitochondrial complex I at a resolution of 3.6 to 3.9 angstroms, describing in detail the central subunits that execute the bioenergetic function. A continuous axis of basic and acidic residues running centrally through the membrane arm connects the ubiquinone reduction site in the hydrophilic arm to four putative proton-pumping units. The binding position for a substrate analogous inhibitor and blockage of the predicted ubiquinone binding site provide a model for the "deactive" form of the enzyme. The proposed transition into the active form is based on a concerted structural rearrangement at the ubiquinone reduction site, providing support for a two-state stabilization-change mechanism of proton pumping.