@article{EilmannBuchmannSiegwolfetal.2010, author = {Eilmann, Britta and Buchmann, Nina and Siegwolf, Rolf and Saurer, Matthias and Cherubini, Paolo and Rigling, Andreas}, title = {Fast response of Scots pine to improved water availability reflected in tree-ring width and δ13C}, series = {Plant, Cell and Environment}, volume = {33}, journal = {Plant, Cell and Environment}, number = {8}, publisher = {Wiley-Blackwell}, address = {Oxford}, issn = {1365-3040 (Online)}, doi = {10.1111/j.1365-3040.2010.02153.x}, pages = {1351 -- 1360}, year = {2010}, abstract = {Drought-induced forest decline, like the Scots pine mortality in inner-Alpine valleys, will gain in importance as the frequency and severity of drought events are expected to increase. To understand how chronic drought affects tree growth and tree-ring δ13C values, we studied mature Scots pine in an irrigation experiment in an inner-Alpine valley. Tree growth and isotope analyses were carried out at the annual and seasonal scale. At the seasonal scale, maximum δ13C values were measured after the hottest and driest period of the year, and were associated with decreasing growth rates. Inter-annual δ13C values in early- and latewood showed a strong correlation with annual climatic conditions and an immediate decrease as a response to irrigation. This indicates a tight coupling between wood formation and the freshly produced assimilates for trees exposed to chronic drought. This rapid appearance of the isotopic signal is a strong indication for an immediate and direct transfer of newly synthesized assimilates for biomass production. The fast appearance and the distinct isotopic signal suggest a low availability of old stored carbohydrates. If this was a sign for C-storage depletion, an increasing mortality could be expected when stressors increase the need for carbohydrate for defence, repair or regeneration.}, language = {en} } @article{EgliAyerPeteretal.2010, author = {Egli, Simon and Ayer, Fran{\c{c}}ois and Peter, Martina and Eilmann, Britta and Rigling, Andreas}, title = {Is forest mushroom productivity driven by tree growth? Results from a thinning experiment}, series = {Annals of Forest Science}, volume = {67}, journal = {Annals of Forest Science}, number = {5}, publisher = {Springer}, address = {Paris}, issn = {1286-4560 (Print)}, doi = {10.1051/forest/2010011}, pages = {509}, year = {2010}, abstract = {• Most of the edible forest mushrooms are mycorrhizal and depend on carbohydrates produced by the associated trees. Fruiting patterns of these fungi are not yet fully understood since climatic factors alone do not completely explain mushroom occurrence. • The objective of this study was to retrospectively find out if changing tree growth following an increment thinning has influenced the diversity patterns and productivity of associated forest mushrooms in the fungus reserve La Chan{\´e}az, Switzerland. • The results reveal a clear temporal relationship between the thinning, the growth reaction of trees and the reaction of the fungal community, especially for the ectomycorrhizal species. The tree-ring width of the formerly suppressed beech trees and the fruit body number increased after thinning, leading to a significantly positive correlation between fruit body numbers and tree-ring width. • Fruit body production was influenced by previous annual tree growth, the best accordance was found between fruit body production and the tree-ring width two years previously. • The results support the hypothesis that ectomycorrhizal fruit body production must be linked with the growth of the associated host trees. Moreover, the findings indicate the importance of including mycorrhizal fungi as important players when discussing a tree as a carbon source or sink.}, language = {en} } @article{DobbertinEilmannBleuleretal.2010, author = {Dobbertin, Matthias and Eilmann, Britta and Bleuler, Peter and Giuggiola, Arnaud and Graf Pannatier, Elisabeth and Landolt, Werner and Schleppi, Patrick and Rigling, Andreas}, title = {Effect of irrigation on needle morphology, shoot and stem growth in a drought-exposed Pinus sylvestris forest}, series = {Tree Physiology}, volume = {30}, journal = {Tree Physiology}, number = {3}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1758-4469 (Online)}, doi = {10.1093/treephys/tpp123}, pages = {346 -- 360}, year = {2010}, abstract = {In Valais, Switzerland, Scots pines (Pinus sylvestris L.) are declining, mainly following drought. To assess the impact of drought on tree growth and survival, an irrigation experiment was initiated in 2003 in a mature pine forest, approximately doubling the annual precipitation. Tree crown transparency (lack of foliage) and leaf area index (LAI) were annually assessed. Seven irrigated and six control trees were felled in 2006, and needles, stem discs and branches were taken for growth analysis. Irrigation in 2004 and 2005, both with below-average precipitation, increased needle size, area and mass, stem growth and, with a 1-year delay, shoot length. This led to a relative decrease in tree crown transparency (-14\%) and to an increase in stand LAI (+20\%). Irrigation increased needle length by 70\%, shoot length by 100\% and ring width by 120\%, regardless of crown transparency. Crown transparency correlated positively with mean needle size, shoot length and ring width and negatively with specific leaf area. Trees with high crown transparency (low growth, short needles) experienced similar increases in needle mass and growth with irrigation than trees with low transparency (high growth, long needles), indicating that seemingly declining trees were able to 'recover' when water supply became sufficient. A simple drought index before and during the irrigation explained most of the variation found in the parameters for both irrigated and control trees.}, language = {en} } @article{DegeringEggertPulsetal.2010, author = {Degering, Christian and Eggert, Thorsten and Puls, Michael and Bongaerts, Johannes and Evers, Stefan and Maurer, Karl-Heinz and Jaeger, Karl-Erich}, title = {Optimization of protease secretion in Bacillus subtilis and Bacillus licheniformis by screening of homologous and herologous signal peptides}, series = {Applied and environmental microbiology}, volume = {76}, journal = {Applied and environmental microbiology}, number = {19}, publisher = {American Society for Microbiology}, address = {Washington, DC}, issn = {1098-5336 (E-Journal); 0003-6919 (Print); 0099-2240 (Print)}, doi = {10.1128/AEM.01146-10}, pages = {6370 -- 6378}, year = {2010}, abstract = {Bacillus subtilis and Bacillus licheniformis are widely used for the large-scale industrial production of proteins. These strains can efficiently secrete proteins into the culture medium using the general secretion (Sec) pathway. A characteristic feature of all secreted proteins is their N-terminal signal peptides, which are recognized by the secretion machinery. Here, we have studied the production of an industrially important secreted protease, namely, subtilisin BPN′ from Bacillus amyloliquefaciens. One hundred seventy-three signal peptides originating from B. subtilis and 220 signal peptides from the B. licheniformis type strain were fused to this secretion target and expressed in B. subtilis, and the resulting library was analyzed by high-throughput screening for extracellular proteolytic activity. We have identified a number of signal peptides originating from both organisms which produced significantly increased yield of the secreted protease. Interestingly, we observed that levels of extracellular protease were improved not only in B. subtilis, which was used as the screening host, but also in two different B. licheniformis strains. To date, it is impossible to predict which signal peptide will result in better secretion and thus an improved yield of a given extracellular target protein. Our data show that screening a library consisting of homologous and heterologous signal peptides fused to a target protein can identify more-effective signal peptides, resulting in improved protein export not only in the original screening host but also in different production strains.}, language = {en} } @article{CzarneckiWinkelmannSpiliopoulou2010, author = {Czarnecki, Christian and Winkelmann, Axel and Spiliopoulou, Myra}, title = {Services in electronic telecommunication markets: a framework for planning the virtualization of processes}, series = {Electronic Markets}, volume = {20}, journal = {Electronic Markets}, number = {3-4}, publisher = {Springer}, address = {Berlin}, issn = {1422-8890}, doi = {10.1007/s12525-010-0045-8}, pages = {197 -- 207}, year = {2010}, abstract = {The potential of electronic markets in enabling innovative product bundles through flexible and sustainable partnerships is not yet fully exploited in the telecommunication industry. One reason is that bundling requires seamless de-assembling and re-assembling of business processes, whilst processes in telecommunication companies are often product-dependent and hard to virtualize. We propose a framework for the planning of the virtualization of processes, intended to assist the decision maker in prioritizing the processes to be virtualized: (a) we transfer the virtualization pre-requisites stated by the Process Virtualization Theory in the context of customer-oriented processes in the telecommunication industry and assess their importance in this context, (b) we derive IT-oriented requirements for the removal of virtualization barriers and highlight their demand on changes at different levels of the organization. We present a first evaluation of our approach in a case study and report on lessons learned and further steps to be performed.}, language = {en} } @article{ChristenKowalskiBartelt2010, author = {Christen, Marc and Kowalski, Julia and Bartelt, Perry}, title = {RAMMS: Numerical simulation of dense snow avalanches in three-dimensional terrain}, series = {Cold Regions Science and Technology}, volume = {63}, journal = {Cold Regions Science and Technology}, number = {1-2}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1872-7441}, doi = {10.1016/j.coldregions.2010.04.005}, pages = {1 -- 14}, year = {2010}, abstract = {Numerical avalanche dynamics models have become an essential part of snow engineering. Coupled with field observations and historical records, they are especially helpful in understanding avalanche flow in complex terrain. However, their application poses several new challenges to avalanche engineers. A detailed understanding of the avalanche phenomena is required to construct hazard scenarios which involve the careful specification of initial conditions (release zone location and dimensions) and definition of appropriate friction parameters. The interpretation of simulation results requires an understanding of the numerical solution schemes and easy to use visualization tools. We discuss these problems by presenting the computer model RAMMS, which was specially designed by the SLF as a practical tool for avalanche engineers. RAMMS solves the depth-averaged equations governing avalanche flow with accurate second-order numerical solution schemes. The model allows the specification of multiple release zones in three-dimensional terrain. Snow cover entrainment is considered. Furthermore, two different flow rheologies can be applied: the standard Voellmy-Salm (VS) approach or a random kinetic energy (RKE) model, which accounts for the random motion and inelastic interaction between snow granules. We present the governing differential equations, highlight some of the input and output features of RAMMS and then apply the models with entrainment to simulate two well-documented avalanche events recorded at the Vall{\´e}e de la Sionne test site.}, language = {en} } @article{ChristenBarteltKowalski2010, author = {Christen, Marc and Bartelt, Perry and Kowalski, Julia}, title = {Back calculation of the In den Arelen avalanche with RAMMS: Interpretation of model results}, series = {Annals of Glaciology}, volume = {51}, journal = {Annals of Glaciology}, number = {54}, publisher = {Cambridge University Press}, address = {Cambridge}, isbn = {1727-5644}, doi = {10.3189/172756410791386553}, pages = {161 -- 168}, year = {2010}, abstract = {Two- and three-dimensional avalanche dynamics models are being increasingly used in hazard-mitigation studies. These models can provide improved and more accurate results for hazard mapping than the simple one-dimensional models presently used in practice. However, two- and three-dimensional models generate an extensive amount of output data, making the interpretation of simulation results more difficult. To perform a simulation in three-dimensional terrain, numerical models require a digital elevation model, specification of avalanche release areas (spatial extent and volume), selection of solution methods, finding an adequate calculation resolution and, finally, the choice of friction parameters. In this paper, the importance and difficulty of correctly setting up and analysing the results of a numerical avalanche dynamics simulation is discussed. We apply the two-dimensional simulation program RAMMS to the 1968 extreme avalanche event In den Arelen. We show the effect of model input variations on simulation results and the dangers and complexities in their interpretation.}, language = {en} } @article{BoernerFunkeHendricketal.2010, author = {B{\"o}rner, Sebastian and Funke, Harald and Hendrick, P. and Recker, E.}, title = {Control system modifications for a hydrogen fuelled gas-turbine}, series = {Proceedings of ISROMAC 13}, journal = {Proceedings of ISROMAC 13}, publisher = {Curran}, address = {Red Hook, NY}, isbn = {978-1-617-38848-4}, pages = {665 -- 670}, year = {2010}, language = {en} } @article{BaeckerPoghossianAbouzaretal.2010, author = {B{\"a}cker, Matthias and Poghossian, Arshak and Abouzar, Maryam H. and Wenmackers, Sylvia and Janssens, Stoffel D. and Haenen, Ken and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Capacitive field-effect (bio-)chemical sensors based on nanocrystalline diamond films}, series = {Diamond Electronics and Bioelectronics — Fundamentals to Applications III, edited by P. Bergonzo, [u.a.]}, journal = {Diamond Electronics and Bioelectronics — Fundamentals to Applications III, edited by P. Bergonzo, [u.a.]}, pages = {1 -- 6}, year = {2010}, language = {en} } @article{BuniatyanAbouzarMartirosyanetal.2010, author = {Buniatyan, Vahe V. and Abouzar, Maryam H. and Martirosyan, Norayr W. and Schubert, J{\"u}rgen and Gevorgian, Spartak and Sch{\"o}ning, Michael Josef and Poghossian, Arshak}, title = {pH-sensitive properties of barium strontium titanate (BST) thin films prepared by pulsed laser deposition technique}, series = {Physica Status Solidi (A). 207 (2010), H. 4}, journal = {Physica Status Solidi (A). 207 (2010), H. 4}, isbn = {1862-6300}, pages = {824 -- 830}, year = {2010}, language = {en} } @article{BragardSoltauThomasetal.2010, author = {Bragard, Michael and Soltau, N. and Thomas, S. and De Doncker, R. W.}, title = {The balance of renewable sources and user demands in grids : power electronics for modular battery energy storage systems}, series = {IEEE transactions on power electronics}, volume = {25}, journal = {IEEE transactions on power electronics}, number = {12}, publisher = {IEEE}, address = {New York}, issn = {0885-8993}, doi = {10.1109/TPEL.2010.2085455}, pages = {3049 -- 3056}, year = {2010}, abstract = {The continuously growing amount of renewable sources starts compromising the stability of electrical grids. Contradictory to fossil fuel power plants, energy production of wind and photovoltaic (PV) energy is fluctuating. Although predictions have significantly improved, an outage of multi-MW offshore wind farms poses a challenging problem. One solution could be the integration of storage systems in the grid. After a short overview, this paper focuses on two exemplary battery storage systems, including the required power electronics. The grid integration, as well as the optimal usage of volatile energy reserves, is presented for a 5- kW PV system for home application, as well as for a 100- MW medium-voltage system, intended for wind farm usage. The efficiency and cost of topologies are investigated as a key parameter for large-scale integration of renewable power at medium- and low-voltage.}, language = {en} } @article{BouquegneauKernRousseau2010, author = {Bouquegneau, Christian and Kern, Alexander and Rousseau, Alain}, title = {Lightning safety guidelines}, pages = {6 Seiten}, year = {2010}, abstract = {This paper introduces lightning to the layman, noting the right behaviour in front of thunderstorms as well as protective measures against lightning. It also contributes to the prevention of lightning injuries and damages. This report was prepared by the authors inside the AHG1 Group for IEC TC81 (Lightning Protection).}, language = {en} } @article{BohrnStuetzFleischeretal.2010, author = {Bohrn, Ulrich and St{\"u}tz, Evamaria and Fleischer, Maximilian and Sch{\"o}ning, Michael Josef}, title = {Real-time detection of CO by eukaryotic cells}, series = {Procedia Engineering}, volume = {5}, journal = {Procedia Engineering}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1877-7058}, pages = {17 -- 20}, year = {2010}, abstract = {In this contribution, we focus on the detection of toxic gases with living eukaryotic cells. A cell-based gas sensor system, able to measure the effects of direct exposure of gases to cells in real-time, was set up. Impedance data as well as oxygen consumption of Chinese hamster lung fibroblast cells (V79) were analysed upon exposure to carbon monoxide (CO). The CO (diluted in wet synthetic air) affects the cell respiration as indicated by an attenuated respiration signal after the CO exposure as well as an instant increase of the capacitive part of the impedance signal during the gas exposure.}, language = {en} } @article{BlomeChiconeHehletal.2010, author = {Blome, Hans-Joachim and Chicone, Carmen and Hehl, Friedrich W. and Mashhoon, Bahram}, title = {Nonlocal modification of Newtonian gravity}, series = {Physical Review D}, volume = {81}, journal = {Physical Review D}, number = {6}, publisher = {American Physical Society}, address = {Melville, NY}, issn = {0556-2821}, doi = {10.1103/PhysRevD.81.065020}, year = {2010}, abstract = {The Newtonian regime of a recent nonlocal extension of general relativity is investigated. Nonlocality is introduced via a scalar "constitutive" kernel in a special case of the translational gauge theory of gravitation, namely, the teleparallel equivalent of general relativity. In this theory, the nonlocal aspect of gravity simulates dark matter. A nonlocal and nonlinear generalization of Poisson's equation of Newtonian gravitation is presented. The implications of nonlocality for the gravitational physics in the solar system are briefly studied.}, language = {en} } @article{BialonskiHorstmannLehnertz2010, author = {Bialonski, Stephan and Horstmann, Marie-Therese and Lehnertz, Klaus}, title = {From brain to earth and climate systems: Small-world interaction networks or not?}, series = {Chaos: An Interdisciplinary Journal of Nonlinear Science}, volume = {20}, journal = {Chaos: An Interdisciplinary Journal of Nonlinear Science}, number = {1}, publisher = {AIP Publishing}, address = {Melville, NY}, issn = {1089-7682}, doi = {10.1063/1.3360561}, pages = {013134}, year = {2010}, abstract = {We consider recent reports on small-world topologies of interaction networks derived from the dynamics of spatially extended systems that are investigated in diverse scientific fields such as neurosciences, geophysics, or meteorology. With numerical simulations that mimic typical experimental situations, we have identified an important constraint when characterizing such networks: indications of a small-world topology can be expected solely due to the spatial sampling of the system along with the commonly used time series analysis based approaches to network characterization.}, language = {en} } @article{BerretzSkorupaSanderetal.2010, author = {Berretz, Frank and Skorupa, Sascha and Sander, Volker and Belloum, Adam}, title = {Towards an actor-driven workflow management system for grids}, series = {Proceedings of 2010 International Symposium on Collaborative Technologies and Systems}, journal = {Proceedings of 2010 International Symposium on Collaborative Technologies and Systems}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4244-6619-1}, doi = {10.1109/CTS.2010.5478458}, pages = {611 -- 616}, year = {2010}, abstract = {Currently, most workflow management systems in Grid environments provide push-oriented job distribution strategies, where jobs are explicitly delegated to resources. In those scenarios the dedicated resources execute submitted jobs according to the request of a workflow engine or Grid wide scheduler. This approach has various limitations, particularly if human interactions should be integrated in workflow execution. To support human interactions with the benefit of enabling inter organizational computation and community approaches, this poster paper proposes the idea of a pull-based task distribution strategy. Here, heterogeneous resources, including human interaction, should actively select tasks for execution from a central repository. This leads to special demands regarding security issues like access control. In the established push-based job execution the resources are responsible for granting access to workflows and job initiators. In general this is done by access control lists, where users are explicitly mapped to local accounts according to their policies. In the pull-based approach the resources actively apply for job executions by sending requests to a central task repository. This means that every resource has to be able to authenticate against the repository to be authorized for task execution. In other words the authorization is relocated from the resources to the repository. The poster paper introduces current work regarding to the mentioned security aspects in the pull-based approach within the scope of the project "HiX4AGWS".}, language = {en} } @article{Bernecker2010, author = {Bernecker, Andreas}, title = {A European Private Company: Is Europe's single legal form for SMEs close to approval?}, series = {Research Briefing}, journal = {Research Briefing}, publisher = {Deutsche Bank Research}, address = {Frankfurt a. M.}, issn = {2193-5955}, year = {2010}, abstract = {This Research Briefing, issued in July 2010, concluded that: - Small and medium-sized enterprises (SMEs) in Europe have long called for a matching legal form valid across the EU (similar to that of the European company (SE) for large firms) - The main benefits would be the availability of uniform Europe-wide company structures, significant cost reductions for businesses and further integration of the internal market - Given the differing national views regarding the concrete features of the new legal form there is currently no sign of an agreement being reached at the European level in the short term; however, it is possible that progress will be made in negotiations during the year - The key issues being discussed in depth are company formation, transnationality and employee participation rights in the new European private company (SPE).}, language = {en} } @article{BehbahaniProbstMaietal.2010, author = {Behbahani, Mehdi and Probst, M. and Mai, A. and Tran, L. and Vonderstein, K. and Keschenau, P. and Linde, T. and Steinseifer, U. and Behr, M. and Mottaghy, K.}, title = {The influence of high shear on thrombosis and hemolysis in artificial organs}, series = {The International Journal of Artificial Organs}, volume = {33}, journal = {The International Journal of Artificial Organs}, number = {7}, publisher = {Sage}, address = {Thousand Oaks}, issn = {0391-3988}, pages = {426 -- 426}, year = {2010}, language = {en} } @article{BehbahaniProbstMaietal.2010, author = {Behbahani, Mehdi and Probst, M. and Mai, A. and Behr, M. and Tran, L. and Vonderstein, K. and Mottaghy, K.}, title = {Numerical Prediction of Blood Damage in Biomedical Devices}, year = {2010}, language = {en} } @article{BehbahaniNamWalugaetal.2010, author = {Behbahani, Mehdi and Nam, J. and Waluga, C. and Behr, M. and Pasquali, M. and Mottaghy, K.}, title = {Modeling and Numerical Analysis of Platelet Activation, Adhesion and Aggregation in Artificial Organs}, volume = {56}, number = {2}, publisher = {Lippincott Williams \& Wilkins}, address = {Philadelphia}, doi = {10.1097/01.mat.0000369377.65122.a3}, pages = {85}, year = {2010}, language = {en} }