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Gusewell S.,Berne University of Applied science | Gusewell S.,ETH Zurich | Klotzli F.,ETH Zurich
Eco.mont | Year: 2012

Protected areas in the Alps are dissected by high-traffic roads for tourist access and transit. Road construction leaves disturbed areas with open soil, which may serve as starting points for the invasion of alien plants or ruderal lowland plants into the protected mountain habitats. In the 1960s, a transit road was widened in the Swiss National Park (SNP) and disturbed roadsides were sown with mixtures of grassland species. Roadside development and vegetation dynamics in the adjacent subalpine pine (Pinus mugo) forest were monitored in permanent plots from 1969 till 2010. Over the 42-year monitoring period, the sown species disappeared progressively and were replaced by species from naturally disturbed areas as well as by forest species. A standard seed mixture and native seeds introduced with local hay developed similarly. Sown species did not expand into the natural habitats and no alien species colonized the roadsides, despite the long-term persistence of open soil. The impact of roadsides on the local flora was therefore minimal. Ecological indicator values suggest that the development of roadsides in the SNP was determined by harsh conditions resulting from a continental subalpine climate and poorly developed soils on dolomite. Therefore, the developments observed in the SNP and the proposed low impact of roadsides on the natural vegetation may not hold for other Alpine regions with different geology and a more oceanic climate.

Ruegsegger M.B.,University of Bern | Geiser D.,Berne University of Applied science | Steiner P.,University of Bern | Pica A.,University of Bern | And 2 more authors.
Medical Physics | Year: 2014

Purpose: External beam radiation therapy is currently considered the most common treatment modality for intraocular tumors. Localization of the tumor and efficient compensation of tumor misalignment with respect to the radiation beam are crucial. According to the state of the art procedure, localization of the target volume is indirectly performed by the invasive surgical implantation of radiopaque clips or is limited to positioning the head using stereoscopic radiographies. This work represents a proof-of-concept for direct and noninvasive tumor referencing based on anterior eye topography acquired using optical coherence tomography (OCT). Methods: A prototype of a head-mounted device has been developed for automatic monitoring of tumor position and orientation in the isocentric reference frame for LINAC based treatment of intraocular tumors. Noninvasive tumor referencing is performed with six degrees of freedom based on anterior eye topography acquired using OCT and registration of a statistical eye model. The proposed prototype was tested based on enucleated pig eyes and registration accuracy was measured by comparison of the resulting transformation with tilt and torsion angles manually induced using a custom-made test bench. Results: Validation based on 12 enucleated pig eyes revealed an overall average registration error of 0.26 ± 0.08° in 87 ± 0.7 ms for tilting and 0.52 ± 0.03°in 94 ± 1.4 ms for torsion. Furthermore, dependency of sampling density on mean registration error was quantitatively assessed. Conclusions: The tumor referencing method presented in combination with the statistical eye model introduced in the past has the potential to enable noninvasive treatment and may improve quality, efficacy, and flexibility of external beam radiotherapy of intraocular tumors. © 2014 American Association of Physicists in Medicine.

Gaj P.,Silesian University of Technology | Jasperneite J.,Ostwestfalen-Lippe University of Applied Sciences | Felser M.,Berne University of Applied science
IEEE Transactions on Industrial Informatics | Year: 2013

Nowadays, computer systems are presented in almost all types of human activity and they support any kind of industry as well. Most of these systems are distributed where the communication between nodes is based on computer networks of any kind. Connectivity between system components is the key issue when designing distributed systems, especially systems of industrial informatics. The industrial area requires a wide range of computer communication means, particularly time-constrained and safety-enhancing ones. From fieldbus and industrial Ethernet technologies through wireless and internet-working solutions to standardization issues, there are many aspects of computer networks uses and many interesting research domains. Lots of them are quite sophisticated or even unique. The main goal of this paper is to present the survey of the latest trends in the communication domain of industrial distributed systems and to emphasize important questions as dependability, and standardization. Finally, the general assessment and estimation of the future development is provided. The presentation is based on the abstract description of dataflow within a system. © 2005-2012 IEEE.

Hoigne D.,Cantonal Hospital Lucerne | Hauck R.,Berne University of Applied science | Babst R.,Cantonal Hospital Lucerne
Archives of Orthopaedic and Trauma Surgery | Year: 2011

Endomedullary femur nails with a head-neck implant offer an up to now unused point of reference for the determination of rotation during osteosynthesis. The lateral femur nail (LFN) or the long Proximal Femur Nail (long PFNA), for example, have recon screws or a blade placed at a 10°angle to the distal locking screw in the transversal plane. If the head-neck implant is inserted properly, the rotation of the femur can be measured with the C-arm taking the hole of the distal locking screw and the posterior condylar tangential line as reference lines. If the posterior condylar tangential line is parallel to the axes of the hole of the distal locking screw, then the rotation or anteversion of the femur is equal to the angle between the head-neck implant and the distal locking screw which is 10°with LFN or long PFNA. Differing rotation angles can be made visible by rotating the C-arm from the axial projection of the distal locking screw up to the posterior condylar tangential line. Three exemplary cases are presented. The recommended method was effective. The rotation of the femur can be measured intraoperatively with this technique and many revisions can be avoided. © 2011 Springer-Verlag.

Tartakovsky L.,University of Zagreb | Baibikov V.,University of Zagreb | Comte P.,Berne University of Applied science | Czerwinski J.,Berne University of Applied science | And 3 more authors.
Atmospheric Environment | Year: 2015

Ultrafine particles (UFP) are major contributors to air pollution due to their easy gas-like penetration into the human organism, causing adverse health effects. This study analyzes UFP emissions by buses of different technologies (from Euro II till Euro V EEV - Enhanced Environmentally-friendly Vehicle) at low-load regimes. Additionally, the emission-reduction potential of retrofitting with a diesel particle filter (DPF) is demonstrated. A comparison of the measured, engine-out, particle number concentrations (PNC) for buses of different technological generations shows that no substantial reduction of engine-out emissions at low-load operating modes is observed for newer bus generations. Retrofitting the in-use urban and interurban buses of Euro II till Euro IV technologies by the VERT-certified DPF confirmed its high efficiency in reduction of UFP emissions. Particle-count filtration efficiency values of the retrofit DPF were found to be extremely high - greater than 99.8%, similar to that of the OEM filter in the Euro V bus. © 2015 Elsevier Ltd.

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