799 research outputs found

    Discovering Implicational Knowledge in Wikidata

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    Knowledge graphs have recently become the state-of-the-art tool for representing the diverse and complex knowledge of the world. Examples include the proprietary knowledge graphs of companies such as Google, Facebook, IBM, or Microsoft, but also freely available ones such as YAGO, DBpedia, and Wikidata. A distinguishing feature of Wikidata is that the knowledge is collaboratively edited and curated. While this greatly enhances the scope of Wikidata, it also makes it impossible for a single individual to grasp complex connections between properties or understand the global impact of edits in the graph. We apply Formal Concept Analysis to efficiently identify comprehensible implications that are implicitly present in the data. Although the complex structure of data modelling in Wikidata is not amenable to a direct approach, we overcome this limitation by extracting contextual representations of parts of Wikidata in a systematic fashion. We demonstrate the practical feasibility of our approach through several experiments and show that the results may lead to the discovery of interesting implicational knowledge. Besides providing a method for obtaining large real-world data sets for FCA, we sketch potential applications in offering semantic assistance for editing and curating Wikidata

    8H-Chromeno[2′,3′:4,5]imidazo[2,1-a]isoquinoline

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    The title compound, C18H12N2O, comprises two aromatic fragments, viz., imidazo[2,1-a]isoquinoline and benzene, linked by oxygen and methyl­ene bridges. Despite the absence of a common conjugative system within the mol­ecule, it adopts an essentially planar conformation with an r.m.s. deviation of 0. 036 Å. In the crystal, due to this structure, mol­ecules form stacks along the b axis by π⋯π stacking inter­actions, with shortest C⋯C distances in the range 3.340 (4)–3.510 (4) Å. The mol­ecules are bound by inter­molecular C—H⋯O inter­actions within the stacks and C—H⋯π inter­actions between the stacks

    Trichinella pseudospiralis outbreak in France.

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    Four persons became ill with trichinellosis after eating meat from a wild boar hunted in Camargue, France. Nonencapsulated larvae of Trichinella pseudospiralis were detected in meat and muscle biopsy specimens. The diagnoses were confirmed by molecular typing. Surveillance for the emerging T. pseudospiralis should be expanded

    Saproxylic species are linked to the amount and isolation of dead wood across spatial scales in a beech forest

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    ContextDead wood is a key habitat for saproxylicspecies, which are often used as indicators of habitatquality in forests. Understanding how the amount andspatial distribution of dead wood in the landscapeaffects saproxylic communities is therefore importantfor maintaining high forest biodiversity.ObjectivesWe investigated effects of the amountand isolation of dead wood on the alpha and betadiversity of four saproxylic species groups, with afocus on how the spatial scale influences results.MethodsWe inventoried saproxylic beetles, wood-inhabiting fungi, and epixylic bryophytes and lichenson 62 plots in the Sihlwald forest reserve in Switzer-land. We used GLMs to relate plot-level speciesrichness to dead wood amount and isolation on spatialscales of 20–200 m radius. Further, we used GDMs todetermine how dead wood amount and isolationaffected beta diversity.ResultsA larger amount of dead wood increasedbeetle richness on all spatial scales, while isolation hadno effect. For fungi, bryophytes and lichens this wasonly true on small spatial scales. On larger scales ofour study, dead wood amount had no effect, whilegreater isolation decreased species richness. Further,we found no strong consistent patterns explaining betadiversity

    Postglacial species arrival and diversity buildup of northern ecosystems took millennia

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    What drives ecosystem buildup, diversity, and stability? We assess species arrival and ecosystem changes across 16 millennia by combining regional-scale plant sedimentary ancient DNA from Fennoscandia with near-complete DNA and trait databases. We show that postglacial arrival time varies within and between plant growth forms. Further, arrival times were mainly predicted by adaptation to temperature, disturbance, and light. Major break points in ecological trait diversity were seen between 13.9 and 10.8 calibrated thousand years before the present (cal ka BP), as well as break point in functional diversity at 12.0 cal ka BP, shifting from a state of ecosystem buildup to a state where most habitat types and biotic ecosystem components were in place. Trait and functional diversity stabilized around 8 cal ka BP, after which both remained stable, although changes in climate took place and species inflow continued. Our ecosystem reconstruction indicates a millennial-scale time phase of formation to reach stable and resilient levels of diversity and functioning.publishedVersio

    GrassPlot v. 2.00 – first update on the database of multi-scale plant diversity in Palaearctic grasslands

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    Abstract: GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). Following a previous Long Database Report (Dengler et al. 2018, Phyto- coenologia 48, 331–347), we provide here the first update on content and functionality of GrassPlot. The current version (GrassPlot v. 2.00) contains a total of 190,673 plots of different grain sizes across 28,171 independent plots, with 4,654 nested-plot series including at least four grain sizes. The database has improved its content as well as its functionality, including addition and harmonization of header data (land use, information on nestedness, structure and ecology) and preparation of species composition data. Currently, GrassPlot data are intensively used for broad-scale analyses of different aspects of alpha and beta diversity in grassland ecosystems

    High resolution ancient sedimentary DNA shows that alpine plant diversity is associated with human land use and climate change.

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    The European Alps are highly rich in species, but their future may be threatened by ongoing changes in human land use and climate. Here, we reconstructed vegetation, temperature, human impact and livestock over the past ~12,000 years from Lake Sulsseewli, based on sedimentary ancient plant and mammal DNA, pollen, spores, chironomids, and microcharcoal. We assembled a highly-complete local DNA reference library (PhyloAlps, 3923 plant taxa), and used this to obtain an exceptionally rich sedaDNA record of 366 plant taxa. Vegetation mainly responded to climate during the early Holocene, while human activity had an additional influence on vegetation from 6 ka onwards. Land-use shifted from episodic grazing during the Neolithic and Bronze Age to agropastoralism in the Middle Ages. Associated human deforestation allowed the coexistence of plant species typically found at different elevational belts, leading to levels of plant richness that characterise the current high diversity of this region. Our findings indicate a positive association between low intensity agropastoral activities and precipitation with the maintenance of the unique subalpine and alpine plant diversity of the European Alps

    Histopathological differences of myotonic dystrophy type 1 (DM1) and PROMM/DM2

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    Muscle biopsy findings in DM2 have been reported to be similar to those in DM1. The authors used myosin heavy chain immunohistochemistry and enzyme histochemistry for fiber type differentiation on muscle biopsies. Their results show that DM2 patients display a subpopulation of type 2 nuclear clump and other very small fibers and, hence, preferential type 2 fiber atrophy in contrast to type 1 fiber atrophy in DM1 patients
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