Alpine grassland vegetation at Gornergrat (Canton of Valais, Switzerland) : vegetation mapping for environ-mental planning

Alpine landscapes are increasingly used by tourism. At the highly frequented Gornergrat in Switzerland there was a need to develop a concept to demerge the paths of hikers and mountain bikers and thus enable a conflict-free use for all user groups. The present study aimed at providing vegetation maps of the sensible areas at Gornergrat to derive recommendations for the planning and restoration of the new trail network. For this purpose, we sampled 32 vegetation plots (10 m²). These were then subjected to TWINSPAN classification, and the derived five units characterized by their diagnostic species based on standardized phi-values. We used ANOVA to test for differences of these units with regard to environmental parameters. The five distinguished vegetation units were assigned to syntaxa down to the alliance level. Finally, a mapping key was derived from the synoptic table to allow the delimitation of units in the field, which resulted in two vegetation maps. We found protected habitats and vascular plant species, as well as a species of the Red List of vascular plants in the study area. Especially at the Riffel Lake, the area has striking disturbances of vegetation due to trampling, which has increased significantly in the last 30 years. For the Gornergrat concept we thus recommend (i) to make the disturbed vegetation at the eastern lake shore inaccessible to visitors, (ii) to restore this part with low-intensity measures and (iii) not to lead the planned new changes through sensitive areas (snow beds and fens)

Does perceived crowding cause winter backcountry recreationists to displace?

Winter backcountry sports such as skiing and snowshoeing have experienced a tremendous increase in popularity in recent decades in the European Alps. Recreationists commonly encounter other recreationists on their route. Because enjoying solitude and being close to nature are important motivations for pursing winter backcountry activities, crowding on back country routes is highly likely to diminish recreational experiences, with potential consequences for nature and recreationists. This study explored perceptions of and responses to crowding among Swiss backcountry skiers and snowshoers, using an online survey that asked about their motivations for pursing their activity and gauged their perception of crowding using the ‘‘people at one time’’ approach. Each of the 830 participants rated 4 scenarios on a 9-point Likert scale ranging from ‘‘far too few people’’ to ‘‘far too many people’’ and answered follow-up questions about potential displacement choices in response to perceived crowding. Participants rarely perceived backcountry routes as having too few people but often perceived them as crowded. We found only minor differences in perceptions of crowding among participants pursuing different activities or those with different motivations. The most common reaction to perceived crowding was to avoid the route in the future, and the next most common was to adjust a route to avoid the crowd on the day in question. This indicates that crowding is likely to lead to short- and long-term spatial displacement of winter backcountry sport activities. This is likely to have a negative impact on wildlife—as well as on backcountry recreationists’ safety, because they might inadvertently enter avalanche-prone areas

Wildlife and humans in outdoor recreational areas near cities

<p>In Naherholungsräumen von Städten herrscht reger Betrieb: am Tag, aber auch in Randzeiten und teils gar in der Nacht. Wildtiere und deren Lebensräume geraten dadurch unter Druck. In stark frequentierten Gebieten sind Rehe weniger aktiv und für viele Wildtierarten ist der Lebensraum reduziert. Wildruhezonen, eine eingeschränkte Er- schliessung und die Lenkung der Besuchenden verbessern die Lebensbedingungen der Wildtiere.</p> <p> </p

On the performances of different IMRT treatment planning systems for selected paediatric cases

BACKGROUND: To evaluate the performance of seven different TPS (Treatment Planning Systems: Corvus, Eclipse, Hyperion, KonRad, Oncentra Masterplan, Pinnacle and PrecisePLAN) when intensity modulated (IMRT) plans are designed for paediatric tumours. METHODS: Datasets (CT images and volumes of interest) of four patients were used to design IMRT plans. The tumour types were: one extraosseous, intrathoracic Ewing Sarcoma; one mediastinal Rhabdomyosarcoma; one metastatic Rhabdomyosarcoma of the anus; one Wilm's tumour of the left kidney with multiple liver metastases. Prescribed doses ranged from 18 to 54.4 Gy. To minimise variability, the same beam geometry and clinical goals were imposed on all systems for every patient. Results were analysed in terms of dose distributions and dose volume histograms. RESULTS: For all patients, IMRT plans lead to acceptable treatments in terms of conformal avoidance since most of the dose objectives for Organs At Risk (OARs) were met, and the Conformity Index (averaged over all TPS and patients) ranged from 1.14 to 1.58 on primary target volumes and from 1.07 to 1.37 on boost volumes. The healthy tissue involvement was measured in terms of several parameters, and the average mean dose ranged from 4.6 to 13.7 Gy. A global scoring method was developed to evaluate plans according to their degree of success in meeting dose objectives (lower scores are better than higher ones). For OARs the range of scores was between 0.75 ± 0.15 (Eclipse) to 0.92 ± 0.18 (Pinnacle(3 )with physical optimisation). For target volumes, the score ranged from 0.05 ± 0.05 (Pinnacle(3 )with physical optimisation) to 0.16 ± 0.07 (Corvus). CONCLUSION: A set of complex paediatric cases presented a variety of individual treatment planning challenges. Despite the large spread of results, inverse planning systems offer promising results for IMRT delivery, hence widening the treatment strategies for this very sensitive class of patients

The Rossiter-McLaughlin effect in Exoplanet Research

The Rossiter-McLaughlin effect occurs during a planet's transit. It provides the main means of measuring the sky-projected spin-orbit angle between a planet's orbital plane, and its host star's equatorial plane. Observing the Rossiter-McLaughlin effect is now a near routine procedure. It is an important element in the orbital characterisation of transiting exoplanets. Measurements of the spin-orbit angle have revealed a surprising diversity, far from the placid, Kantian and Laplacian ideals, whereby planets form, and remain, on orbital planes coincident with their star's equator. This chapter will review a short history of the Rossiter-McLaughlin effect, how it is modelled, and will summarise the current state of the field before describing other uses for a spectroscopic transit, and alternative methods of measuring the spin-orbit angle.Comment: Review to appear as a chapter in the "Handbook of Exoplanets", ed. H. Deeg & J.A. Belmont

Impaired Heat Shock Response in Cells Expressing Full-Length Polyglutamine-Expanded Huntingtin

The molecular mechanisms by which polyglutamine (polyQ)-expanded huntingtin (Htt) causes neurodegeneration in Huntington's disease (HD) remain unclear. The malfunction of cellular proteostasis has been suggested as central in HD pathogenesis and also as a target of therapeutic interventions for the treatment of HD. We present results that offer a previously unexplored perspective regarding impaired proteostasis in HD. We find that, under non-stress conditions, the proteostatic capacity of cells expressing full length polyQ-expanded Htt is adequate. Yet, under stress conditions, the presence of polyQ-expanded Htt impairs the heat shock response, a key component of cellular proteostasis. This impaired heat shock response results in a reduced capacity to withstand the damage caused by cellular stress. We demonstrate that in cells expressing polyQ-expanded Htt the levels of heat shock transcription factor 1 (HSF1) are reduced, and, as a consequence, these cells have an impaired a heat shock response. Also, we found reduced HSF1 and HSP70 levels in the striata of HD knock-in mice when compared to wild-type mice. Our results suggests that full length, non-aggregated polyQ-expanded Htt blocks the effective induction of the heat shock response under stress conditions and may thus trigger the accumulation of cellular damage during the course of HD pathogenesis