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We report the first-ever basin-wide geomorphological characterization of a high-resolution bathymetry map in a steeply incised valley-occupying intra-mountainous lake in the Eastern Alps. The resulting new geomorphological map of Lake Hallstatt is then combined with high-resolution reflection seismic and sedimentary core analyses to document, characterize and date recent (<200 years) subaquatic landslides. The area is located in the UNESCO World Heritage Cultural Landscape of the Hallstatt–Dachstein area, famous for its well-documented medieval and prehistoric human settlement history. This allows us to calibrate observed mass-transport deposits (MTDs) in the high-resolution sedimentary archive (sedimentation rates c.0.5 cm a−1) of this deep lake dominated by clastic sedimentation.The hydro-acoustic data document a multitude of different MTDs linked to rock falls, subaqueous slope failures and shore collapses. Sediment cores document laminated background sediments intercalated with distinct event deposits that can be linked to historically documented major flood events and moderately strong earthquakes. Our study suggests that the larger MTDs result from earthquake-triggered subaquatic delta slope instabilities and that the deeper subsurface provides evidence of even larger mass-movement processes, yet to be validated by longer cores. Thus, Lake Hallstatt is a potential natural laboratory for studying causes and consequences of subaquatic landslides in steeply incised intra-mountainous lakes and comparable fjord settings.

New high-resolution surveying techniques allow subaqueous geomorphology to be investigated in great detail. Such analyses are important as the morphologies are often indicative of past processes, including mass movements. For peri-alpine Lake Zurich, many mass-wasting events have occurred in the past millennia. While the ages of these events are known from past studies on the respective deposits in the lake basin, the surface expressions and distribution of the respective features on the slopes have not been extensively described. Here we quantitatively characterize the morphologic features on the entire lake floor. A total of 50 subaqueous landslides are morphologically identified in a high-resolution digital bathymetric model (DBM), mapped and characterized using a geographic information system (GIS). Many slides show relatively small erosion areas (<0.05 km2) and are located in shallow water (<10 m water depth). The roughness of the individual landslide-translation areas is quantified using the standard deviation of a measure called bathymetric position index (BPI) and related to the slides ages. The DBM allows the detection of traces of mass-movements dating back to c.5000 cal years BP. Our results demonstrate that morphometric analyses on a high-resolution DBM can contribute to a better understanding of sublacustrine mass movements.

A 22-week-old 21-kg female Bernese Mountain Dog ingested a topical antipsoriatic preparation containing the synthetic vitamin D analog tacalcitol. The dog died after a history of lethargy, recumbency, paresis of the hindlimbs, increased rectal temperature, dyspnea, and hematemesis. Histologic examination revealed metastatic calcification in the kidneys, lungs, myocardium, brain, stomach, and tear glands. The appearance of soft tissue mineralization in multiple organs is consistent with hypercalcemia derived from excessive vitamin D uptake. Oral toxicity studies for tacalcitol in the dog are not available, but the present report emphasizes the extraordinary toxic risk of drugs containing this vitamin D analog to dogs.

Gastrointestinal stromal tumors (GISTs) are defined as specific CD117-(Kit, stem cell factor receptor) expressing tumors of the gastrointestinal (GI) tract. They are believed to originate from the interstitial pacemaker cells of Cajal (ICC) or their progenitor cells. In horses only a few cases of GISTs are described in the literature. In the present paper the macroscopical, histological, immunohistochemical, and ultrastructural features of an equine cecal GIST are described.