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As a key component of a circular economy, remanufacturing is gaining popularity across various sectors. This paper focuses on the wind energy sector, a major player in renewable technologies, which is gradually recognizing its increasing resource-intensive material usage. We present a case study outlining a method for selecting parts from an industrial supply chain partner’s inventory. This strategy is further employed to streamline the manufacturing processes for the chosen part. We utilized the Weighted Sum method, a multi-criteria decision-making strategy, in both instances. We discuss how expertise of process specialists and multi-criteria decision-making techniques could be synthesised for adopting a remanufacturing approach. Data from the commercial partners was collected and any identifying information was stripped. From this, we discovered that the Yaw gear pinion shaft is the top candidate for remanufacturing due to its high commercial value. After comparing various additive manufacturing technologies, Arc Directed Energy Deposition stands out as the best fit for remanufacturing this particular pinion shaft. Although our initial aim was to consider additive manufacturing technologies as solutions for remanufacturing, we show how even conventional manufacturing processes, such as friction welding, could emerge as strong contenders.

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The Kilianstollen Marsberg (Rhenish Massif, Germany) has been extensively mined for copper ores, dating from early medieval period until 1945. The exposed organic-rich alum shale rocks influenced by the diverse mine drainages at an ambient temperature of 10 ∘ C could naturally enrich biogeochemically distinct heavy metal resistant microbiota. This amplicon-sequence-based study evaluates the microbially colonized subterranean rocks of the abandoned copper mine Kilianstollen to characterize the colonization patterns and biogeochemical pathways of individual microbial groups. Under the selective pressure of the heavy metal contaminated environment at illuminated sites, Chloroflexi (Ktedonobacteria) and Cyanobacteria (Oxyphotobacteria) build up whitish–greenish biofilms. In contrast, Proteobacteria, Firmicutes and Actinobacteria dominate rocks around the uncontaminated spring water streams. The additional metagenomic analysis revealed that the heavy metal resistant microbiome was evidently involved in redox cycling of transition metals (Cu, Zn, Co, Ni, Mn, Fe, Cd, Hg). No deposition of metals or minerals, though, was observed by transmission electron microscopy in Ktedonobacteria biofilms which may be indicative for the presence of different detoxification pathways. The underlying heavy metal resistance mechanisms, as revealed by analysis of metagenome-assembled genomes, were mainly attributed to transition metal efflux pumps, redox enzymes, volatilization of Hg, methylated intermediates of As 3+ , and reactive oxygen species detoxification pathways. [ABSTRACT FROM AUTHOR]

Comparative pore water-sediment studies are crucial to trace biogeochemical and early diagenetic interactions between mineral and fluid phases. They are commonly conducted in stable environments with long-time diagenetic reactions between sediment and pore water. In contrast, this work presents a comparative study within the Cinq Cases pool system, a shallow and saline water body, with occasional marine influx and short-time diagenetic reactions between sediment and pore water. Cinq Cases is located on the Aldabra atoll in the western Indian Ocean. Sediments span ca. 3800 years and indicate three environmental stages: (i) An initial, at least temporary anoxic, palustrine environment, including meteoric diagenesis (Unit III), (ii) slow marine flooding, with cyanobacteria and sponge blooms (Unit II), and (iii) lagoon flooding, including oxic conditions within the sediment (Unit I). Such frequent changes in diagenetic environments of small water bodies can be retraced by three different proxies representing partially overlapping but different time scales: (i) sediments reflect ancient processes (ii) pore waters are influenced by recent processes, and (iii) bacterial communities reflect an overlay of ancient and recent processes. [ABSTRACT FROM AUTHOR]

The defossilization of the electricity and heat supply in the chemical industry poses a significant challenge. In particular, the intended feed‐in of volatile renewable electricity into the chemical processes may conflict with the need for a constant, secure and affordable electricity and heat supply for chemical plants. Adapted concepts for the operation of the cogeneration plant, which is located at the chemical site, play a central role. The present work defines a so‐called ideal‐typical utility infrastructure (iUI). The iUI is a means to exemplarily investigate the operational behavior of utility infrastructures and furthermore to identify defossilization options for process steam and electricity supply at chemical sites. [ABSTRACT FROM AUTHOR]

The identification and distinction of fluvial from lacustrine deposits and the recognition of catchment changes are crucial for the reconstruction of climate changes in terrestrial environments. The investigated drill core succession shows a general evolution from red–brown claystones to white–grey marlstones and microcrystalline limestones, which all have previously been considered as relict deposits of an impact ejecta‐dammed lake, falling within the mid‐Miocene Climate Transition. However, recent mammal biostratigraphic dating suggests a likely pre‐impact age. Indeed, no pebbles from impact ejecta have been detected; only local clasts of Mesozoic formations, in addition to rare Palaeozoic lydites from outside of the study area. Lithofacies analysis demonstrates only the absence of lacustrine criteria, except for one charophyte‐bearing mudstone. Instead, the succession is characterized by less diagnostic floodplain fines with palaeosols, palustrine limestones with root voids and intercalated thin sandstone beds. Carbonate isotope signatures of the mottled marlstones, palustrine limestones and mud‐supported conglomerates substantiate the interpretation of a fluvial setting. Low, invariant δ18Ocarb reflects a short water residence time and highly variable δ13Ccarb indicates a variable degree of pedogenesis. Carbonate 87Sr/86Sr ratios of the entire succession show a unidirectional trend from 0.7103 to 0.7112, indicating a change of the solute provenance from Triassic to Jurassic rocks, identical to the provenance trend from extraclasts. The increase in carbonate along the succession is therefore independent from climate changes but reflects a base‐level rise from the level of the siliciclastic Upper Triassic to the carbonate‐bearing Lower to Middle Jurassic bedrocks. This study demonstrates that, when information on sedimentary architecture is limited, a combination of facies criteria (i.e. presence or absence of specific sedimentary structures and diagnostic organisms), component provenance, and stable and radiogenic isotopes is required to unequivocally distinguish between lacustrine and fluvial sediments, and to disentangle regional geological effects in the catchment and climate influences. [ABSTRACT FROM AUTHOR]

Chronic inflammation with progressive age, called inflammaging, contributes to the pathogenesis of cardiovascular diseases. Previously, we have shown increased vascular expression of the Carcinoembryonic antigen‐related cell adhesion molecule 1 (CEACAM1) in aged mice and humans, presumably via mutual upregulation with the pro‐inflammatory cytokine TNF‐α. CEACAM1 is critical for aging‐associated vascular alterations like endothelial dysfunction, fibrosis, oxidative stress, and sustained inflammation and can be regarded as a main contributor to vascular inflammaging. This study was conducted to elucidate the mechanisms underlying endothelial CEACAM1 upregulation by TNF‐α in detail. Using wildtype (WT) and TNF‐α knockout (Tnf−/−) mice, we confirmed that the aging‐related upregulation of endothelial CEACAM1 critically depends on TNF‐α. The underlying mechanisms were analyzed in an endothelial cell culture model. TNF‐α time‐dependently upregulated CEACAM1 in vitro. In pharmacological experiments, we identified an early NF‐κB‐ and a delayed β‐catenin‐mediated response. Involvement of β‐catenin was further substantiated by siRNA‐mediated knockdown of the β‐catenin‐targeted transcription factor TCF4. Both signaling pathways acted independent from each other. Elucidating the delayed response, co‐immunoprecipitation analysis revealed release of β‐catenin from adherens junctions by TNF‐α. Finally, TNF‐α activated Akt kinase by increasing its Ser473 phosphorylation. Consequently, Akt kinase facilitated β‐catenin signaling by inhibiting its degradation via phosphorylation of GSK3β at Ser9 and by increased phosphorylation of β‐catenin at Ser552 that augments its transcriptional activity. Taken together, our study provides novel mechanistic insights into the aging‐related, inflammation‐mediated endothelial upregulation of CEACAM1. Beyond the pathogenesis of cardiovascular diseases, these findings may be significant to all fields of inflammaging. [ABSTRACT FROM AUTHOR]

The Kilianstollen Marsberg (Rhenish Massif, Germany) has been extensively mined for copper ores, dating from Early Medieval Period till 1945. The exposed organic-rich alum shale rocks influenced by the diverse mine drainages at an ambient temperature of 10 °C could naturally enrich biogeochemically distinct heavy metal resistant microbiota. This metagenomic study evaluates the microbially colonized subterranean rocks of the abandoned copper mine Kilianstollen to characterize the colonization patterns and biogeochemical pathways of individual microbial groups. Under the selective pressure of the heavy metal contaminated environment at illuminated sites, Chloroflexi (Ktedonobacteria) and Cyanobacteria (Oxyphotobacteria) build up whitish-greenish biofilms. In contrast, Proteobacteria, Firmicutes and Actinobacteria dominate rocks around the uncontaminated spring water streams. The metagenomic analysis revealed that the heavy metal resistant microbiome was evidently involved in redox cycling of transition metals (Cu, Zn, Co, Ni, Mn, Fe, Cd, Hg). No deposition of metals or minerals, though, was observed by transmission electron microscopy in Ktedonobacteria biofilms which may be indicative for the presence of different detoxification pathways. The underlying heavy metal resistance mechanisms, as revealed by analysis of metagenome-assembled genomes, were mainly attributed to transition metal efflux pumps, redox enzymes, volatilization of Hg0, methylated intermediates of As(III) and reactive oxygen species detoxification pathways. [ABSTRACT FROM AUTHOR]

Since its recognition as an impact structure 60 years ago, no volcanics were anticipated in the circular depression of the 14.8 Ma old Nördlinger Ries. Here, we describe for the first time a volcanic ash‐derived clinoptilolite‐heulandite‐buddingtonite bed within the 330 m thick Miocene lacustrine crater fill. Zircon U‐Pb ages of 14.20 ± 0.08 Ma point to the source of the volcanic ash in the Pannonian Basin, 760 km east of the Ries. The diagenetically derived zeolite‐feldspar bed occurs in laminated claystones of the Ries soda‐lake stage and represents the first unequivocal stratigraphic marker bed in this basin, traceable from marginal surface outcrops to 218 m below surface in the crater center. These relationships demonstrate a deeply bowl‐shaped geometry of crater fill sediments, not explainable by sediment compaction and corresponding stratigraphic backstripping alone. Since most of the claystones formed at shallow water depths, the bowl‐shaped geometry must reflect 134 +23/−49 m of sagging of the crater floor. We attribute the sagging to compaction and closure of the dilatant macro‐porosity of the deeply fractured and brecciated crater floor during basin sedimentation and loading, a process that lasted for more than 0.6 Myr. As a result, the outcrop pattern of the lithostratigraphic crater‐fill units in its present erosional plane forms a concentric pattern. Recognition of this volcanic ash stratigraphic marker in the Ries crater provides insights into the temporal and stratigraphic relationships of crater formation and subsidence that have implications for impact‐hosted lakes on Earth and Mars. Plain Language Summary: We describe for the first time a volcanic ash layer from the lake sediment fill of the 14.8 million years old asteroid impact crater Nördlinger Ries. Radiometric age and trace element characteristics of this ash layer are identical to that of a volcanic field in Hungary, so that the ash reflects a volcanic eruption 760 km east of the Ries basin. Recognition of this ash layer enables its use as a marker bed. The ash layer can be traced from surface outcrops to 218 m depth in drillings. This indicates that the strata are significantly inclined toward the crater center. Calculations of sediment compaction by further sediment load and burial only partially explain the observed deeply bowl‐shaped geometry. We attribute the additional sagging to the subsidence of the crater floor substrate, formed of rocks highly shattered by the impact event. Both effects cause a concentric pattern of outcropping strata in the partially eroded crater fill. The presence of the ash layer and its use to help disentangle the source and timing of subsidence (due to compaction of lake sediments, and closure of deeper, impact‐induced fractures), has important implications for lakes formed in impact craters on Earth and Mars. Key Points: A critical question in the evolution of impact‐crater‐hosted lakes is the origin and timing of post‐impact floor subsidenceWe describe a volcanic ash layer from the Ries impact crater that demonstrates a deeply bowl‐shaped geometry of its lacustrine crater fillThis geometry, leading to a concentric outcrop pattern, requires significant crater floor sagging, in addition to sediment compaction [ABSTRACT FROM AUTHOR]

Despite advances regarding the microbial and organic-molecular impact on nucleation, the formation of dolomite in sedimentary environments is still incompletely understood. Since 1960, apparent dolomite formation has been reported from mud sediments of the shallow, oligohaline and alkaline Lake Neusiedl, Austria. To trace potential dolomite formation or diagenetic alteration processes in its deposits, lake water samples and sediment cores were analyzed with respect to sediment composition, hydrochemistry and bacterial community composition. Sediments comprise 20 cm of homogenous mud with 60 wt % carbonate, which overlies dark-laminated consolidated mud containing 50 wt % carbonate and plant debris. Hydrochemical measurements reveal a shift from oxic lake water with pH 9.0 to anoxic sediment pore water with pH 7.5. A decrease in SO42- with a concomitant increase in ΣH2S and NH4+ from 0 to 15 cm core depth indicates anaerobic heterotrophic decomposition, including sulfate reduction. The bacterial community composition reflects the zonation indicated by the pore water chemistry, with a distinct increase in fermentative taxa below 15 cm core depth. The water column is highly supersaturated with respect to (disordered) dolomite and calcite, whereas saturation indices of both minerals rapidly approach zero in the sediment. Notably, the relative proportions of different authigenic carbonate phases and their stoichiometric compositions remain constant with increasing core depth. Hence, evidence for Ca–Mg carbonate formation or ripening to dolomite is lacking within the sediment of Lake Neusiedl. As a consequence, precipitation of high-magnesium calcite (HMC) and protodolomite does not occur in association with anoxic sediment and sulfate-reducing conditions. Instead, analytical data for Lake Neusiedl suggest that authigenic HMC and protodolomite precipitate from the supersaturated, well-mixed aerobic water column. This observation supports an alternative concept to dolomite formation in anoxic sediments, comprising Ca–Mg carbonate precipitation in the water column under aerobic and alkaline conditions. [ABSTRACT FROM AUTHOR]

Ex situ microelectrode experiments, using cyanobacterial biofilms, are conducted under various pH, temperature and constant-alkalinity conditions in order to examine the effects of changing environmental parameters on cyanobacterial photosynthesis-induced calcification. The ability of the biological systems to mitigate the effects of environmental perturbation is a key factor that should be considered while predicting the effects of increased atmospheric partial C[O.sub.2] pressure on process such as calcification and in interpreting microfossils in the fossil record.

Despite advances regarding the microbial and organic-molecular impact on nucleation, the formation of dolomite in sedimentary environments is still incompletely understood. Since 1960, apparent dolomite formation has been reported from mud sediments of the shallow, oligohaline and alkaline Lake Neusiedl, Austria. To trace potential dolomite formation or diagenetic alteration processes in its deposits, lake water samples and sediment cores were analyzed with respect to sediment composition, hydrochemistry and bacterial community composition. Sediments comprise 20 cm of homogenous mud with 60 wt % carbonate, which overlie dark-laminated consolidated mud containing 50 wt % carbonate and plant debris. Hydrochemical measurements reveal a shift from oxic lake water with pH 9.0 to anoxic sediment pore water with pH 7.5. A decrease in SO42- with a concomitant increase of ΣH2S and NH4+ from 0-15 cm core depth, indicates anaerobic heterotrophic decomposition, including sulfate reduction. The bacterial community composition reflects the zonation indicated by the pore water chemistry, with a distinct increase of fermentative taxa below 15 cm core depth. The water column is highly supersaturated with respect to (disordered) dolomite and calcite, whereas saturation indices of both minerals rapidly approach zero in the sediment. Notably, the relative proportions of different authigenic carbonate phases and their stoichiometric compositions remain constant with increasing core depth. Hence, evidence for Ca-Mg carbonate formation or ripening to dolomite is lacking within the sediment of Lake Neusiedl. As a consequence, precipitation of high-magnesium-calcite (HMC) and very-high-magnesium-calcite (VHMC) does not occur in association with anoxic sediment and sulfate reducing conditions. Instead, analytical data for Lake Neusiedl suggest that authigenic HMC and VHMC precipitate from the supersaturated, well-mixed aerobic water column. This observation supports an alternative concept to dolomite formation in anoxic sediments, comprising Ca-Mg carbonate precipitation in the water column under aerobic and alkaline conditions. [ABSTRACT FROM AUTHOR]

The 26 km diameter Nördlinger Ries is a complex impact structure with a ring structure that resembles a peak ring. A first research drilling through this "inner crystalline ring" of the Ries was performed at the Erbisberg hill (SW Ries) to better understand the internal structure and lithology of this feature, and possibly reveal impact‐induced hydrothermal alteration. The drill core intersected the slope of a 22 m thick postimpact travertine mound, before entering 42 m of blocks and breccias of crystalline rocks excavated from the Variscan basement at >500 m depth. Weakly shocked gneiss blocks that show that shock pressure did not exceed 5 GPa occur above polymict lithic breccias of shock stage Ia (10–20 GPa), with planar fractures and planar deformation features (PDFs) in quartz. Only a narrow zone at 49.20–50.00 m core depth exhibits strong mosaicism in feldspar and {101¯2} PDFs in quartz, which are indicative of shock stage Ib (20–35 GPa). Finally, 2 m of brecciated Keuper sediments at the base of the section point to an inverse layering of strata. While reverse grading of clast sizes in lithic breccias and gneiss blocks is consistent with lateral transport, the absence of diaplectic glass and melt products argues against dynamic overthrusting of material from a collapsing central peak, as seen in the much larger Chicxulub structure. Indeed, weakly shocked gneiss blocks are rather of local provenance (i.e., the transient crater wall), whereas moderately shocked polymict lithic breccias with geochemical composition and 87Sr/86Sr signature similar to Ries suevite were derived from a position closer to the impact center. Thus, the inner ring of the Ries is formed by moderately shocked polymict lithic breccias likely injected into the transient crater wall during the excavation stage and weakly shocked gneiss blocks of the collapsing transient crater wall that were emplaced during the modification stage. While the presence of an overturned flap is not evident from the Erbisberg drilling, a survey of all drillings at or near the inner ring point to inverted strata throughout its outer limb. Whether the central ring of the Ries represents remains of a collapsed central peak remains to be shown. Postimpact hydrothermal alteration along the Erbisberg section comprises chloritization, sulfide veinlets, and strong carbonatization. In addition, a narrow zone in the lower parts of the polymict lithic breccia sequence shows a positive Eu anomaly in its carbonate phase. The surface expression of this hydrothermal activity, i.e., the travertine mound, comprises subaerial as well as subaquatic growth phases. Intercalated lake sediments equivalent to the early parts of the evolution of the central crater basin succession confirm a persistent impact‐generated hydrothermal activity, although for less time than previously suggested. [ABSTRACT FROM AUTHOR]

Albian carbonate mud-mound limestones exposed near Iraneta, northern Spain, show a fabric- and particle-specific fluorescence. Intense fluorescence is restricted to in situ precipitated microcrystalline (automicritic) fabrics, calcified demosponges, and coralline sponges. Intermediate intensity derives from micritized bioclasts, pellets, and a rim of marine bladed cement. Most invertebrate skeletons, late-diagenetic equant cement, and crosscutting zones of dolomitization are weakly to nonfluorescent. Internal microcrystalline sediment (allomicrite) and red algae debris have variable fluorescence. Correlation between rock fluorescence and soluble humic substances was evaluated from 3 g of automicrite, allomicrite, and cement. Time-resolved laser-induced fluorescence spectroscopy (TRLFS) with ultra-short pulses on two extracrystalline fractions (NaOH-soluble) and two intracrystalline fractions (HCl-soluble and NaOH-soluble) showed that most of the soluble humic substances of automicrite are within the crystals; but conversely, are significantly enriched on outer surfaces of allomicrite. Spar cement is close to detection limits. Fluorescence lifetimes are in the range of 0.5-2 ns and 3.5-6 ns. We conclude that precipitation of automicrite took place during oxidative organic matter diagenesis, i.e., during condensation reactions of degradation products of marine biopolymers. By contrast, allomicrite formed by skeletal breakdown followed by ingestion, organic coating, and reingestion during deposit feeding. A humic-substance--based model of marine polymer gels represents a new approach for the understanding of ancient polygenetic carbonate muds, so typical of Phanerozoic mud-mounds in deeper water settings. Keywords: micrite, mud-mound, cementation, humic substances, fluorescence.

One of the subtasks of automated map labelling that has received little attention so far is the labelling of areas. Geographic areas are often are represented by concave polygons which pose severe limitations on straightforward solutions due to their great variety of shape, a fact worsened by the lack of measures for quantifying feature-label relationships. We introduce a novel and efficient algorithm for labelling area features externally, i.e. outside their polygonal boundary. Two main contributions are presented in the following. First, it is a highly optimized algorithm of generating candidate placements utilizing algorithms from the field of computational geometry. Second, we describe a measure for scoring label positions. Both solutions based on a series of well-established cartographic precepts about name positioning in the case of semantic enclaves such as islands or lakes. The results of our experiments show that our algorithm can efficiently place labels with a quality that is close to the quality of traditional cartographic products made by human cartographers. [ABSTRACT FROM PUBLISHER]

Calcification of freshwater streams and the involvement of microorganisms in this process are still not fully understood. Here, we report on the metagenomic and metatranscriptomic analyses of bacterial community structures derived from an actively calcifying karst water creek biofilm and underlying tufa by employing next-generation sequencing technologies.The persistent and metabolically active bacterial communities were assessed by DNA-based and RNA-based 16S rRNA gene sequence analysis, respectively. We identified filamentous Cyanobacteria belonging to the Oscillatoriales as the predominant bacterial microorganisms in the biofilm. Cyanobacteria were accompanied by a high diversity of mainly aerobic members affiliated to different bacterial phyla. The second most abundant phylum was Proteobacteria, represented by the classes Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, and Deltaproteobacteria. In addition, Chloroflexi, Planctomycetes, Actinobacteria, Acidobacteria, Bacteroidetes, Spirochaetes, and Verrucomicrobia were present in higher abundances (>0.5%). Several of these phyla included potentially novel subgroups. The tufa stromatolite carbonate one centimeter below the surface exhibited a similar prokaryotic community as the superficial biofilm but showed a lower abundance of Cyanobacteria and a more diverse microbial community. We obtained insights into the in situ microbial metabolism by employing directed sequencing of enriched mRNA (cDNA) and subsequent taxonomic and functional analysis of biofilm-derived reads. High activities in photosynthesis, carbon and protein metabolism were indicated. [ABSTRACT FROM AUTHOR]

We address some of the challenges in representing spatial data with a novel form of geometric abstraction—the stenomap. The stenomap comprises a series of smoothly curving linear glyphs that each represent both the boundary and the area of a polygon. We present an efficient algorithm to automatically generate these open, C1-continuous splines from a set of input polygons. Feature points of the input polygons are detected using the medial axis to maintain important shape properties. We use dynamic programming to compute a planar non-intersecting spline representing each polygon's base shape. The results are stylised glyphs whose appearance may be parameterised and that offer new possibilities in the 'cartographic design space'. We compare our glyphs with existing forms of geometric schematisation and discuss their relative merits and shortcomings. We describe several use cases including the depiction of uncertain model data in the form of hurricane track forecasting; minimal ink thematic mapping; and the depiction of continuous statistical data. [ABSTRACT FROM PUBLISHER]

We present an algorithm that labels linear features with two matched toponyms describing the left and the right side of a line, respectively. Such a pairwise line labeling strategy is commonly used in manually produced maps to differentiate administrative or other geographic divisions. Our approach solves two basic tasks of the automated map labeling problem, namely candidate-position generation and position evaluation for a given scale. The quality of the name placement is evaluated by comparison to a set of established cartographic principles and guidelines for linear features. We give some results of our experiments based on real datasets. The implementation of our algorithm shows that it is simple and robust, and the resulting sample maps demonstrate its practical efficiency. [ABSTRACT FROM AUTHOR]

Traditionally schematised maps make extensive use of curves. However, automated methods for schematisation are mostly restricted to straight lines. We present a generic framework for topology-preserving curved schematisation that allows a choice of quality measures and curve types. The framework fits a curve to every part of the input. It uses Voronoi diagrams to ensure that curves fitted to disjoint parts do not intersect. The framework then employs a dynamic program to find an optimal schematisation using the fitted curves. Our fully-automated approach does not need critical points or salient features. We illustrate our framework with Bézier curves and circular arcs. [ABSTRACT FROM AUTHOR]

While graphic variables in 2D maps have been extensively investigated, 4D cartography is still a widely unexplored field. In this paper, we investigate the usefulness of 4D maps (three spatial dimensions plus time) for cartographically illustrating spatio-temporal environmental phenomena. The presented approach focuses mostly on explorative research rather than on enhancement and extension of existing methods and principles. The user study described in the paper shows that 4D cartography is not a well-explored research area and that many experienced map users try to apply their knowledge from 2D maps to 4D dynamic visualisations. Thus, in order to foster the discussion within the community, we formulated several basic research questions for the area of 4D cartography, which range from methods for representing time in 4D visualisations and understanding the temporal context to finding generic methods to achieve optimized temporal generalisation and a consistent definition of graphical variables for 3D and 4D. [ABSTRACT FROM AUTHOR]

On the Kiritimati atoll, several lakes exhibit microbial mat-formation under different hydrochemical conditions. Some of these lakes trigger microbialite formation such as Lake 21, which is an evaporitic, hypersaline lake (salinity of approximately 170‰). Lake 21 is completely covered with a thick multilayered microbial mat. This mat is associated with the formation of decimeter-thick highly porous microbialites, which are composed of aragonite and gypsum crystals. We assessed the bacterial and archaeal community composition and its alteration along the vertical stratification by large-scale analysis of 16S rRNA gene sequences of the nine different mat layers. The surface layers are dominated by aerobic, phototrophic, and halotolerant microbes. The bacterial community of these layers harbored Cyanobacteria (Halothece cluster), which were accompanied with known phototrophic members of the Bacteroidetes and Alphaproteobacteria. In deeper anaerobic layers more diverse communities than in the upper layers were present. The deeper layers were dominated by Spirochaetes, sulfate-reducing bacteria (Deltaproteobacteria), Chloroflexi (Anaerolineae and Caldilineae), purple non-sulfur bacteria (Alphaproteobacteria), purple sulfur bacteria (Chromatiales), anaerobic Bacteroidetes (Marinilabiacae), Nitrospirae (OPB95), Planctomycetes and several candidate divisions. The archaeal community, including numerous uncultured taxonomic lineages, generally changed from Euryarchaeota (mainly Halobacteria and Thermoplasmata) to uncultured members of the Thaumarchaeota (mainly Marine Benthic Group B) with increasing depth. [ABSTRACT FROM AUTHOR]

Aragonitic microbialites, characterized by a reticulate fabric, were discovered beneath lacustrine microbial mats on the atoll of Kiritimati, Republic of Kiribati, Central Pacific. The microbial mats, with cyanobacteria as major primary producers, grow in evaporated seawater modified by calcium carbonate and gypsum precipitation and calcium influx via surface and/or groundwaters. Despite the high aragonite supersaturation and a high photosynthetic activity, only minor aragonite precipitates are observed in the top parts of the microbial mats. Instead, major aragonite precipitation takes place in lower mat parts at the transition to the anoxic zone. The prokaryotic community shows a high number of phylotypes closely related to halotolerant taxa and/or taxa with preference to oligotrophic habitats. Soil- and plant- inhabiting bacteria underline a potential surface or subsurface influx from terrestrial areas, while chitinase-producing representatives coincide with the occurrence of insect remains in the mats. Strikingly, many of the clones have their closest relatives in microorganisms either involved in methane production or consumption of methane or methyl compounds. Methanogens, represented by the methylotrophic genus Methanohalophilus, appear to be one of the dominant organisms in anaerobic mat parts. All this points to a significant role of methane and methyl components in the carbon cycle of the mats. Nonetheless, thin sections and physicochemical gradients through the mats, as well as the 12C-depleted carbon isotope signatures of carbonates indicate that spherulitic components of the microbialites initiate in the photosynthesis-dominated orange mat top layer, and further grow in the green and purple layer below. Therefore, these spherulites are considered as product of an extraordinary high photosynthesis effect simultaneous to a high inhibition by pristine exopolymers. Then, successive heterotrophic bacterial activity leads to a condensation of the exopolymer framework, and finally to the formation of crevice-like zones of partly degraded exopolymers. Here initiation of horizontal aragonite layers and vertical aragonite sheets of the microbialite occurs, which are considered as a product of high photosynthesis at decreasing degree of inhibition. Finally, at low supersaturation and almost lack of inhibition, syntaxial growth of aragonite crystals at lamellae surfaces leads to thin fibrous aragonite veneers. While sulfate reduction, methylotrophy, methanogenesis and ammonification play an important role in element cycling of the mat, there is currently no evidence for a crucial role of them in CaCO3 precipitation. Instead, photosynthesis and exopolymer degradation sufficiently explain the observed pattern and fabric of microbialite formation. [ABSTRACT FROM AUTHOR]