11 research outputs found
Recent evolution of debris-flow fans in the Central Swiss Alps and associated risk assessment: two examples in Roseg Valley
This paper reports the results of research carried out in the Roseg Valley (Lower Engadine, Switzerland) that examines debris-flow fan typology, debris-flow activity, and the impact of debris flows on forest vegetation. Depositional landforms from debris flows were subdivided according to their degree of geomorphological hazard. An inventory of debris-flow fans and a detailed geomorphological, vegetational, and dendrochronological study of two of them was undertaken. The dendrochronological analysis allowed dating of historical events and reconstruction of their recent evolution. By dating scars and growth anomalies on Larix decidua Mill. and Pinus cembra L., 24 debris-flow events were identified on the Misaun fan and 16 on the Tschierva fan, and differences in their distribution due to drainage basin characteristics identified. Fans chosen for this investigation are crossed by a hiking trail that is frequently used by tourists during the summer season. A qualitative hazard and risk evaluation were undertaken. This approach contributes to hazard assessment on fans, and may also be applied in other environmental contexts (e.g., in trail planning)
Transcatheter mitral valve repair with MitraClip in patients with pulmonary hypertension: Hemodynamic and prognostic perspectives
Transcatheter mitral valve repair with MitraClip has emerged as a possible therapeutic option for patients with severe mitral regurgitation (MR) with high risk for surgical valve repair. MitraClip intervention has demonstrated to improve haemodynamics and clinical outcomes in selected patients in observational and randomized studies. Preoperative pulmonary hypertension (PH) is known to affect prognosis in patients undergoing surgical mitral valve intervention. The aim of the present review is to discuss the available literature focused on the haemodynamic and clinical effects of MitraClip in patients with severe MR and PH. © 2021 The Authors. Published by IMR Press
Mutations in TTC19 cause mitochondrial complex III deficiency and neurological impairment in humans and flies.
Although mutations in CYTB (cytochrome b) or BCS1L have been reported in isolated defects of mitochondrial respiratory chain complex III (cIII), most cIII-defective individuals remain genetically undefined. We identified a homozygous nonsense mutation in the gene encoding tetratricopeptide 19 (TTC19) in individuals from two families affected by progressive encephalopathy associated with profound cIII deficiency and accumulation of cIII-specific assembly intermediates. We later found a second homozygous nonsense mutation in a fourth affected individual. We demonstrated that TTC19 is embedded in the inner mitochondrial membrane as part of two high-molecular-weight complexes, one of which coincides with cIII. We then showed a physical interaction between TTC19 and cIII by coimmunoprecipitation. We also investigated a Drosophila melanogaster knockout model for TTC19 that showed low fertility, adult-onset locomotor impairment and bang sensitivity, associated with cIII deficiency. TTC19 is a putative cIII assembly factor whose disruption is associated with severe neurological abnormalities in humans and flies