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Digitisation in the construction industry continues to advance and, together with the increasing dissemination and further development of hardware and software, is steadily opening up further opportunities for innovative ways of working. Building Information Modelling (BIM) is currently becoming the standard for new construction but has not yet been optimised for use in existing buildings. Therefore, the Institute of Building Materials Research (ibac) is researching new methods and possibilities for BIM-based building preservation. In this paper, the automated creation and analysis of point clouds as well as the implementation of further information from in situ diagnosis and monitoring systems in BIM-Models are presented. On a practical example, the different steps of a subsequent digitisation of an existing building are demonstrated considering new possibilities as autonomous robots and the intelligent utilisation of sensors and diagnostics tools. The goal is a decision support tool, which is independent from proprietary software, adaptive to different types of buildings and open for various interfaces. Current results show that quantifying point clouds and making BIM-models usable beyond the planning and execution phase for new buildings are essential steps for the digitisation of building maintenance. The proposed digital workflow holds great potential for effective building diagnoses and efficient service life management.

In the context of the application of carbon Textile Reinforced Concrete (TRC) layers for the durable repair of building surfaces, uniaxial tensile tests on rectangular TRC samples were carried out to compare the bond and load-bearing behavior of an epoxy-impregnated carbon textile and its surface modified version. The aim of the surface modification, consisting of a subsequent coating with epoxy resin and sanding with quartz sand, is the improvement of the composite material regarding crack width reduction and an increase of the load-bearing capacity. A total of 15 series were examined and the parameters: reinforcement type, orientation and ratio were varied. In addition, long-term load tests were conducted. An optical 3D-video measuring system in combination with a DIC-software was used, which allowed the analysis of the process of crack formation during the entire testing time. With the surface modified reinforcement the formation of approx. 1.5 times the number of cracks with averagely 33 % smaller crack widths and up to 50 % smaller crack spacings were observed, regardless of the ratio of reinforcement. The residual behaviour of the series subjected to a permanent load of 1500 MPa over 1000 h showed no reduction of the tensile stress compared to short-term tests.

In the context of a current joint research project a monitoring system to detect leakages in bridges is implemented by using a textile reinforced concrete interlayer which consists of two carbon meshes with a spacing of 15 mm and a new developed mortar. Between the two carbon meshes the resistivity is measured with alternating current. If a leakage in the bridge deck sealing occurs and water gets into the interlayer a drop in the measured resistivity occurs and the leakage is detected. In this case repair measures can be carried out in an early stage or a preventive cathodic protection can be switched on. To assess which sizes of leakages are detectable under which boundary conditions, laboratory tests and tests on a 100 m2 outdoor demonstrator were carried out. Therefore leakages were artificially produced and the changes in the measured resistivity values were observed under different climatic conditions. Impacts such as the form of the leakages or the position of the leakages in the measuring field were varied.

Carbon textiles are used more and more as reinforcement in concrete structures. Due to their high durability the concrete covers can be extremely thin compared to traditional steel reinforced concrete, resulting in the possibility to build very thin elements with excellent performance. To improve the properties of the carbon textiles, the rovings are normally impregnated with different types of polymers. Additionally to the use as reinforcement, carbon textiles can also be used as anodes for cathodic protection. However, while first tests have shown, that impregnated carbon rovings are suitable to be used as CP-anodes, it is still not clear under which conditions the new types of anodes are stable or when they start to dissolve. This paper describes investigations on the influence of an anodic polarisation on the tensile strength of different types of impregnated carbon rovings.

Abstract Background The identification of vast numbers of unknown organisms using DNA sequences becomes more and more important in ecological and biodiversity studies. In this context, a fragment of the mitochondrial cytochrome c oxidase I (COI) gene has been proposed as standard DNA barcoding marker for the identification of organisms. Limitations of the COI barcoding approach can arise from its single-locus identification system, the effect of introgression events, incomplete lineage sorting, numts, heteroplasmy and maternal inheritance of intracellular endosymbionts. Consequently, the analysis of a supplementary nuclear marker system could be advantageous. Results We tested the effectiveness of the COI barcoding region and of three nuclear ribosomal expansion segments in discriminating ground beetles of Central Europe, a diverse and well-studied invertebrate taxon. As nuclear markers we determined the 18S rDNA: V4, 18S rDNA: V7 and 28S rDNA: D3 expansion segments for 344 specimens of 75 species. Seventy-three species (97%) of the analysed species could be accurately identified using COI, while the combined approach of all three nuclear markers provided resolution among 71 (95%) of the studied Carabidae. Conclusion Our results confirm that the analysed nuclear ribosomal expansion segments in combination constitute a valuable and efficient supplement for classical DNA barcoding to avoid potential pitfalls when only mitochondrial data are being used. We also demonstrate the high potential of COI barcodes for the identification of even closely related carabid species.

The description of a mealybug species found in Germany, Spinococcus kozari Schmutterer, 2002 (Hemiptera: Coccomorpha), is considered invalid because no type material or depository were specified in the original literature. Here a valid description of the same species is provided under the name Peliococcus schmuttereri Caballero and Kaydan sp. n. following the International Code of Zoological Nomenclature. The species is redescribed, with a taxonomic illustration and microphotographs, an updated taxonomic key is provided, and type material and a depository are designated. With this record, the number of species of Peliococcus Borchsenius, 1948 is increased to 37 worldwide and the number of Peliococcus species present in Germany is increased to two, the second species being Peliococcus calluneti (Lindinger, 1912). [ABSTRACT FROM AUTHOR]

Steel corrosion is one of the main factors limiting the durability of existing reinforced concrete components. Based on the corrosive circumstances, different prevention and repair methods can be applied. In the case of carbonation-initiated corrosion, chemical re-alkalisation (CRA) is one of the standard measures to counteract alteration processes in the concrete that lead to reinforcement corrosion. The current state of research on the CRA of carbonated concrete and the various materials that have been investigated in terms of their applicability for this repair measure are summarised. The review summarises current research results in the field of carbonated concrete and the proven pozzolanic reactivity of the carbonation products in contact with portlandite, which suggests an inhibitory effect on CRA, although this has not yet been investigated. There are also initial attempts that deviate from the application of classic Portland cement as a repair material, but their applicability in practice must be questioned. The use of alternative binders and the associated different compositions of pore solutions and varying alkalinity of these binders (e.g. composite cements with a high substitution rate or alkali-activated binders), have not yet been investigated for repair processes such as CRA, although the chemical composition of binders is of the greatest importance for successful application of the repair measure. [ABSTRACT FROM AUTHOR]

This corrects the article DOI: 10.1038/ncomms13428.

This corrects the article DOI: 10.1038/ncomms13428.

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Gerromorpha Popov, 1971 is a fascinating and diverse insect lineage that evolved about 200 Mya to spend their entire life cycle on the air–water interface and have since colonized all types of aquatic habitats. The subfamily Halobatinae Bianchi, 1896 is particularly interesting because some species have adapted to life on the open ocean—a habitat where insects are very rarely found. Several attempts have been made to reconstruct the phylogenetic hypotheses of this subfamily, but the use of a few partial gene sequences recovered only a handful of well-supported relationships, thus limiting evolutionary inferences. Fortunately, the emergence of high-throughput sequencing technologies has enabled the recovery of more genetic markers for phylogenetic inference. We applied genome skimming to obtain mitochondrial and nuclear genes from low-coverage whole-genome sequencing of 85 specimens for reconstructing a well-supported phylogeny, with particular emphasis on Halobatinae. Our study confirmed that Metrocorini Matsuda, 1960, is paraphyletic, whereas Esakia Lundblad, 1933, and Ventidius Distant, 1910, are more closely related to Halobatini Bianchi, 1896, than Metrocoris Mayr, 1865, and Eurymetra Esaki, 1926. We also found that Ventidius is paraphyletic and in need of a taxonomic revision. Ancestral state reconstruction suggests that Halobatinae evolved progressively from limnic to coastal habitats, eventually attaining a marine lifestyle, especially in the genus Halobates Eschscholtz, 1822, where the oceanic lifestyle evolved thrice. Our results demonstrate that genome skimming is a powerful and straightforward approach to recover genetic loci for robust phylogenetic analysis in non-model insects. [ABSTRACT FROM AUTHOR]

Terrestrial ecosystems play a significant role in the global carbon cycle and offset a large fraction of anthropogenic CO2 emissions. The terrestrial carbon sink is increasing, yet the mechanisms responsible for its enhancement, and implications for the growth rate of atmospheric CO2, remain unclear. Here using global carbon budget estimates, ground, atmospheric and satellite observations, and multiple global vegetation models, we report a recent pause in the growth rate of atmospheric CO2, and a decline in the fraction of anthropogenic emissions that remain in the atmosphere, despite increasing anthropogenic emissions. We attribute the observed decline to increases in the terrestrial sink during the past decade, associated with the effects of rising atmospheric CO2 on vegetation and the slowdown in the rate of warming on global respiration. The pause in the atmospheric CO2 growth rate provides further evidence of the roles of CO2 fertilization and warming-induced respiration, and highlights the need to protect both existing carbon stocks and regions, where the sink is growing rapidly.

Any limit on future global warming is associated with a quota on cumulative global CO2 emissions. We translate this global carbon quota to regional and national scales, on a spectrum of sharing principles that extends from continuation of the present distribution of emissions to an equal per-capita distribution of cumulative emissions. A blend of these endpoints emerges as the most viable option. For a carbon quota consistent with a 2°C warming limit (relative to pre-industrial levels), the necessary long-term mitigation rates are very challenging (typically over 5% per year), both because of strong limits on future emissions from the global carbon quota and also the likely short-term persistence in emissions growth in many regions.