TY - JOUR A1 - Raue, Markus A1 - Wambach, M. A1 - Glöggler, S. A1 - Grefen, Dana A1 - Kaufmann, R. A1 - Abetz, C. A1 - Georgopanos, P. A1 - Handge, U. A. A1 - Mang, Thomas A1 - Blümich, B. A1 - Abetz, V. T1 - Investigation of historical hard rubber ornaments of Charles Goodyear JF - Macromolecular chemistry and physics Y1 - 2014 SN - 1022-1352 VL - Vol. 215 IS - No. 3 SP - 245 EP - 254 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Fateri, Miranda A1 - Gebhardt, Andreas T1 - Process Parameters Development of Selective Laser Melting of Lunar Regolith for On-Site Manufacturing Applications JF - International Journal of Applied Ceramic Technology Y1 - 2015 SN - 1744-7402 U6 - https://doi.org/10.1111/ijac.12326 VL - 12 IS - 1 SP - 46 EP - 52 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Fateri, Miranda A1 - Gebhardt, Andreas T1 - Selective Laser Melting of Soda-Lime Glass Powder JF - International Journal of Applied Ceramic Technology Y1 - 2015 U6 - https://doi.org/10.1111/ijac.12338 SN - 1744-7402 VL - 12 IS - 1 SP - 53 EP - 61 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Feichtinger, Linda M. A1 - Eilmann, Britta A1 - Buchmann, Nina A1 - Rigling, Andreas T1 - Trait-specific responses of Scots pine to irrigation on a short vs long time scale JF - Tree Physiology Y1 - 2015 U6 - https://doi.org/10.1093/treephys/tpu114 SN - 1758-4469 (Online) SN - 0829-318X (Print) N1 - Ab 12 Monaten nach Veröffentlichung kostenfrei zugänglich. VL - 35 IS - 00 SP - 1 EP - 12 PB - Heron CY - Victoria, BC ER - TY - JOUR A1 - Mathiak, Gerhard A1 - Willnecker, Rainer A1 - Plescher, Engelbert T1 - Vibrational effects on diffusion experiments JF - Microgravity science and technology : international journal for microgravity research and applications Y1 - 2005 SN - 0938-0108 VL - Vol. 15 IS - No. 1 SP - 295 EP - 300 ER - TY - JOUR A1 - Mathiak, Gerhard A1 - Plescher, Engelbert A1 - Willnecker, Rainer T1 - Liquid metal diffusion experiments in microgravity - Vibrational effects JF - Measurement science and technology Y1 - 2005 U6 - https://doi.org/10.1088/0957-0233/16/2/003 SN - 0957-0233 VL - Vol. 16 IS - No. 2 SP - 336 ER - TY - JOUR A1 - Wagner, Torsten A1 - Miyamoto, K. A1 - Werner, Frederik A1 - Schöning, Michael Josef A1 - Yoshinobu, T. T1 - Utilising Digital Micro-Mirror Device (DMD) as Scanning Light Source for Light-Addressable Potentiometric Sensors (LAPS) Y1 - 2011 U6 - https://doi.org/10.1166/sl.2011.1620 VL - 9 IS - 2 SP - 812 EP - 815 PB - American Scientific Publishers CY - Stevenson Ranch, Calif. ER - TY - JOUR A1 - Schöning, Michael Josef A1 - Poghossian, Arshak T1 - BioFEDs (field-effect devices) : State-of-the-art and new directions JF - Electroanalysis Y1 - 2006 U6 - https://doi.org/10.1002/elan.200603609 SN - 1521-4109 VL - 18 IS - 19-20 SP - 1893 EP - 1900 ER - TY - JOUR A1 - Thust, Marion A1 - Schöning, Michael Josef A1 - Frohnhoff, S. A1 - Arens-Fischer, R. A1 - Kordos, P. A1 - Lüth, H. T1 - Porous silicon as a substrate material for potentiometric biosensors JF - Measurement Science and Technology Y1 - 1996 U6 - https://doi.org/10.1088/0957-0233/7/1/003 VL - 7 IS - 1 SP - 26 EP - 29 ER - TY - JOUR A1 - Schütz, S. A1 - Weißbecker, B. A1 - Hummel, Hans E. A1 - Schöning, Michael Josef A1 - Riemer, A. A1 - Kordos, P. A1 - Lüth, H. T1 - Field effect transistor-insect antenna junction JF - Naturwissenschaften Y1 - 1997 SN - 1432-1904 VL - 84 SP - 86 EP - 88 ER - TY - JOUR A1 - Guo, Yuanyuan A1 - Seki, Kosuke A1 - Miyamoto, Ko-ichiro A1 - Wagner, Torsten A1 - Schöning, Michael Josef A1 - Yoshinobu, Tatsuo T1 - Device simulation of the light-addressable potentiometric sensor with a novel photoexcitation method for a higher spatial resolution JF - Procedia Engineering N2 - A novel photoexcitation method for the light-addressable potentiometric sensor (LAPS) realized a higher spatial resolution of chemical imaging. In this method, a modulated light probe, which generates the alternating photocurrent signal, is surrounded by a ring of constant light, which suppresses the lateral diffusion of photocarriers by enhancing recombination. A device simulation verified that a higher spatial resolution could be obtained by adjusting the gap between the modulated and constant light. It was also found that a higher intensity and a longer wavelength of constant light was more effective. However, there exists a tradeoff between the spatial resolution and the amplitude of the photocurrent, and thus, the signal-to-noise ratio. A tilted incidence of constant light was applied, which could achieve even higher resolution with a smaller loss of photocurrent. KW - Light-addressable Potentiometric Sensor KW - novel photoexcitation method KW - tilted constant illumination KW - spatial resolution Y1 - 2014 U6 - https://doi.org/10.1016/j.proeng.2014.11.369 SN - 1877-7058 N1 - EUROSENSORS 2014 ; European Conference on Solid-State Transducers <28, 2014> VL - 87 SP - 456 EP - 459 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Schusser, Sebastian A1 - Bäcker, Matthias A1 - Krischer, M. A1 - Wenzel, L. A1 - Leinhos, Marcel A1 - Poghossian, Arshak A1 - Biselli, Manfred A1 - Wagner, P. A1 - Schöning, Michael Josef T1 - Enzymatically catalyzed degradation of biodegradable polymers investigated by means of a semiconductor-based field-effect sensor JF - Procedia Engineering N2 - A semiconductor field-effect device has been used for an enzymatically catalyzed degradation of biopolymers for the first time. This novel technique is capable to monitor the degradation process of multiple samples in situ and in real-time. As model system, the degradation of the biopolymer poly(D, L-lactic acid) has been monitored in the degradation medium containing the enzyme lipase from Rhizomucor miehei. The obtained results demonstrate the potential of capacitive field-effect sensors for degradation studies of biodegradable polymers. KW - Field-effect sensor KW - enzymatic (bio)degradation KW - poly(d, l-lactic acid) KW - in-situ monitoring KW - impedance spectroscopy Y1 - 2014 U6 - https://doi.org/10.1016/j.proeng.2014.11.689 SN - 1877-7058 N1 - EUROSENSORS 2014 ; European Conference on Solid-State Transducers <28, 2014> VL - 87 SP - 1314 EP - 1317 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Huck, Christina A1 - Poghossian, Arshak A1 - Bäcker, Matthias A1 - Reisert, Steffen A1 - Schubert, J. A1 - Zander, W. A1 - Begoyan, V. K. A1 - Buniatyan, V. V. A1 - Schöning, Michael Josef T1 - Chemical sensors based on a high-k perovskite oxide of barium strontium titanate JF - Procedia Engineering N2 - High-k perovskite oxide of barium strontium titanate (BST) represents a very attractive multi-functional transducer material for the development of (bio-)chemical sensors for liquids. In this work, BST films have been applied as a sensitive transducer material for a label-free detection of adsorbed charged macromolecules (positively charged polyelectrolytes) and concentration of hydrogen peroxide vapor as well as protection insulator layer for a contactless electrolyte-conductivity sensor. The experimental results of characterization of individual sensors are presented. Special emphasis is devoted towards the development of a capacitively-coupled contactless electrolyte-conductivity sensor. KW - barium strontium titanate KW - high-k material KW - contactless conductivity sensor KW - multi-functional material KW - hydrogen peroxide Y1 - 2014 U6 - https://doi.org/10.1016/j.proeng.2014.11.258 SN - 1877-7058 N1 - EUROSENSORS 2014 ; European Conference on Solid-State Transducers <28, 2014> VL - 87 SP - 28 EP - 31 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Bronder, Thomas A1 - Wu, Chunsheng A1 - Poghossian, Arshak A1 - Werner, Frederik A1 - Keusgen, M. A1 - Schöning, Michael Josef T1 - Label-free detection of DNA hybridization with light-addressable potentiometric sensors: comparison of various DNA-immobilization strategies JF - Procedia Engineering N2 - Light-addressable potentiometric sensors (LAPS) consisting of a p-Si-SiO2 and p-Si-SiO2-Au structure, respectively, have been tested for a label-free electrical detection of DNA (deoxyribonucleic acid) hybridization. Three different strategies for immobilizing single-stranded probe DNA (ssDNA) molecules on a LAPS surface have been studied and compared: (a) immobilization of thiol-modified ssDNA on the patterned Au surface via gold-thiol bond, (b) covalent immobilization of amino-modified ssDNA onto the SiO2 surface functionalized with 3-aminopropyltriethoxysilane and (c) layer-by-layer adsorption of negatively charged ssDNA on a positively charged weak polyelectrolyte layer of poly(allylamine hydrochloride). KW - LAPS KW - lable-free detection KW - DNA hybridization KW - field-effect sensor Y1 - 2014 U6 - https://doi.org/10.1016/j.proeng.2014.11.647 SN - 1877-7058 N1 - EUROSENSORS 2014 ; European Conference on Solid-State Transducers <28, 2014> VL - 87 SP - 755 EP - 758 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Miyamoto, K. A1 - Seki, K. A1 - Wagner, Torsten A1 - Schöning, Michael Josef A1 - Yoshinobu, T. T1 - Enhancement of the spatial resolution of the chemical imaging sensor by a hybrid fiber-optic illumination JF - Procedia Engineering N2 - The chemical imaging sensor, which is based on the principle of the light-addressable potentiometric sensor (LAPS), is a powerful tool to visualize the spatial distribution of chemical species on the sensor surface. The spatial resolution of this sensor depends on the diffusion of photocarriers excited by a modulated light. In this study, a novel hybrid fiber-optic illumination was developed to enhance the spatial resolution. It consists of a modulated light probe to generate a photocurrent signal and a ring of constant light, which suppresses the lateral diffusion of minority carriers excited by the modulated light. It is demonstrated that the spatial resolution was improved from 92 μm to 68 μm. Y1 - 2014 U6 - https://doi.org/10.1016/j.proeng.2014.11.563 SN - 1877-7058 N1 - EUROSENSORS 2014 ; European Conference on Solid-State Transducers <28, 2014> VL - 87 SP - 612 EP - 615 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Bragard, Michael A1 - van Hoek, H. A1 - De Doncker, R. W. T1 - A major design step in IETO concept realization that allows overcurrent protection and pushes limits of switching performance JF - IEEE transactions on power electronics N2 - This paper presents the latest prototype of the integrated emitter turn-off thyristor concept, which potentially ranks among thyristor high-power devices like the gate turn-off thyristor and the integrated gate-commutated thyristor (IGCT). Due to modifications of the external driver stage and mechanical press-pack design optimization, this prototype allows for full device characterization. The turn-off capability was increased to 1600 A with an active silicon area of 823mm2 . This leads to a transient peak power of 672.1kW/cm² . Within this paper, measurements and concept assessment are presented and a comparison to state-of-the-art IGCT devices is provided. Y1 - 2012 U6 - https://doi.org/10.1109/TPEL.2012.2189136 SN - 0885-8993 VL - 27 IS - 9 SP - 4163 EP - 4171 PB - IEEE CY - New York ER - TY - JOUR A1 - Bragard, Michael A1 - Conrad, M. A1 - van Hoek, H. A1 - De Doncker, R. W. T1 - The integrated emitter turn-off thyristor (IETO) : an innovative thyristor-based high power semiconductor device using MOS assisted turn-off JF - IEEE transactions on industry applications Y1 - 2011 U6 - https://doi.org/10.1109/TIA.2011.2161432 SN - 0093-9994 VL - 47 IS - 5 SP - 2175 EP - 2182 PB - IEEE CY - New York ER - TY - JOUR A1 - Dachwald, Bernd A1 - Mikucki, Jill A1 - Tulaczyk, Slawek A1 - Digel, Ilya A1 - Espe, Clemens A1 - Feldmann, Marco A1 - Francke, Gero A1 - Kowalski, Julia A1 - Xu, Changsheng T1 - IceMole : A maneuverable probe for clean in situ analysis and sampling of subsurface ice and subglacial aquatic ecosystems JF - Annals of Glaciology N2 - There is significant interest in sampling subglacial environments for geobiological studies, but they are difficult to access. Existing ice-drilling technologies make it cumbersome to maintain microbiologically clean access for sample acquisition and environmental stewardship of potentially fragile subglacial aquatic ecosystems. The IceMole is a maneuverable subsurface ice probe for clean in situ analysis and sampling of glacial ice and subglacial materials. The design is based on the novel concept of combining melting and mechanical propulsion. It can change melting direction by differential heating of the melting head and optional side-wall heaters. The first two prototypes were successfully tested between 2010 and 2012 on glaciers in Switzerland and Iceland. They demonstrated downward, horizontal and upward melting, as well as curve driving and dirt layer penetration. A more advanced probe is currently under development as part of the Enceladus Explorer (EnEx) project. It offers systems for obstacle avoidance, target detection, and navigation in ice. For the EnEx-IceMole, we will pay particular attention to clean protocols for the sampling of subglacial materials for biogeochemical analysis. We plan to use this probe for clean access into a unique subglacial aquatic environment at Blood Falls, Antarctica, with return of a subglacial brine sample. KW - Antarctic Glaciology KW - Extraterrestrial Glaciology KW - Glaciological instruments and methods KW - Subclacial exploration KW - Subglacial lakes Y1 - 2014 U6 - https://doi.org/10.3189/2014AoG65A004 SN - 1727-5644 VL - 55 IS - 65 SP - 14 EP - 22 PB - Cambridge University Press CY - Cambridge ER - TY - JOUR A1 - Bragard, Michael A1 - Soltau, N. A1 - Thomas, S. A1 - De Doncker, R. W. T1 - The balance of renewable sources and user demands in grids : power electronics for modular battery energy storage systems JF - IEEE transactions on power electronics N2 - 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. Y1 - 2010 U6 - https://doi.org/10.1109/TPEL.2010.2085455 SN - 0885-8993 VL - 25 IS - 12 SP - 3049 EP - 3056 PB - IEEE CY - New York ER - TY - JOUR A1 - Köllensperger, P. A1 - Bragard, Michael A1 - Plum, T. A1 - De Doncker, R. W. T1 - The dual GCT : new high-power device using optimized GCT technology JF - IEEE transactions on industry applications Y1 - 2009 U6 - https://doi.org/10.1109/TIA.2009.2027364 SN - 0093-9994 VL - 45 IS - 5 SP - 1754 EP - 1762 ER - TY - JOUR A1 - Stulpe, Werner T1 - From the attempt of certain classical reformulations of quantum mechanics to quasi-probability representations JF - Journal of Mathematical Physics N2 - The concept of an injective affine embedding of the quantum states into a set of classical states, i.e., into the set of the probability measures on some measurable space, as well as its relation to statistically complete observables is revisited, and its limitation in view of a classical reformulation of the statistical scheme of quantum mechanics is discussed. In particular, on the basis of a theorem concerning a non-denseness property of a set of coexistent effects, it is shown that an injective classical embedding of the quantum states cannot be supplemented by an at least approximate classical description of the quantum mechanical effects. As an alternative approach, the concept of quasi-probability representations of quantum mechanics is considered. Y1 - 2014 U6 - https://doi.org/10.1063/1.4861939 SN - 222-488 N1 - bereits unter gleichem Titel aufgenommen bei arxiv : http://arxiv.org/pdf/1307.2314.pdf VL - 55 IS - 1 PB - AIP Publishing CY - College Park, Md. ER - TY - JOUR A1 - Murib, M. S. A1 - Yeap, W. S. A1 - Martens, D. A1 - Liu, X. A1 - Bienstman, P. A1 - Fahlman, M. A1 - Schöning, Michael Josef A1 - Michiels, L. A1 - Haenen, K. A1 - Serpengüzel, A. A1 - Wagner, Patrick T1 - Photonic studies on polymer-coated sapphire-spheres : a model system for biological ligands JF - Sensors and actuators A: Physical N2 - In this study we show an optical biosensor concept, based on elastic light scattering from sapphire microspheres. Transmitted and elastic scattering intensity of the microspheres (radius 500 μm, refractive index 1.77) on an optical fiber half coupler is analyzed at 1510 nm. The 0.43 nm angular mode spacing of the resonances is comparable to the angular mode spacing value estimated using the optical size of the microsphere. The spectral linewidths of the resonances are in the order of 0.01 nm, which corresponds to quality factors of approximately 105. A polydopamine layer is used as a functionalizing agent on sapphire microspherical resonators in view of biosensor implementation. The varying layer thickness on the microsphere is determined as a function of the resonance wavelength shift. It is shown that polymer functionalization has a minor effect on the quality factor. This is a promising step toward the development of an optical biosensor. Y1 - 2015 U6 - https://doi.org/10.1016/j.sna.2014.11.024 SN - 1873-3069 (E-Journal); 0924-4247 (Print) VL - 222 SP - 212 EP - 219 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Eilmann, Britta A1 - Weber, Pascale A1 - Rigling, Andreas A1 - Eckstein, Dieter T1 - Growth reactions of Pinus sylvestris L. and Quercus pubescens Willd. to drought years at a xeric site in Valais, Switzerland JF - Dendrochronologia Y1 - 2006 U6 - https://doi.org/doi:10.1016/j.dendro.2005.10.002 SN - 1612-0051 (Online) SN - 1125-7865 (Print) VL - 23 IS - 3 SP - 121 EP - 132 ER - TY - JOUR A1 - Fonti, Patrick A1 - Eilmann, Britta A1 - García-González, Ignacio A1 - von Arx, Georg T1 - Expeditious building of ring-porous earlywood vessel chronologies without loosing signal information JF - Trees : structure and function Y1 - 2009 U6 - https://doi.org/10.1007/s00468-008-0310-z SN - 0931-1890 (Print) SN - 1432-2285 (Online) VL - 23 IS - 3 SP - 665 EP - 671 PB - Springer CY - Berlin ER - TY - JOUR A1 - Eilmann, Britta A1 - Buchmann, Nina A1 - Siegwolf, Rolf A1 - Saurer, Matthias A1 - Cherubini, Paolo A1 - Rigling, Andreas T1 - Fast response of Scots pine to improved water availability reflected in tree-ring width and δ13C JF - Plant, Cell and Environment N2 - 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. Y1 - 2010 U6 - https://doi.org/10.1111/j.1365-3040.2010.02153.x SN - 1365-3040 (Online) SN - 0140-7791 (Print) VL - 33 IS - 8 SP - 1351 EP - 1360 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Eilmann, Britta A1 - Zweifel, Roman A1 - Buchmann, Nina A1 - Graf Pannatier, Elisabeth A1 - Rigling, Andreas T1 - Drought alters timing, quantity, and quality of wood formation in Scots pine JF - Journal of Experimental Botany Y1 - 2011 U6 - https://doi.org/10.1093/jxb/erq443 SN - 1460-2431 (Online) SN - 0022-0957 (Print) VL - 62 IS - 8 SP - 2763 EP - 2771 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Wegner, Lena A1 - von Arx, Georg A1 - Sass-Klaassen, Ute G. W. A1 - Eilmann, Britta T1 - ROXAS – an efficient and accurate tool to detect vessels in diffuse-porous species JF - IAWA Journal / International Association of Wood Anatomists Y1 - 2013 U6 - https://doi.org/10.1163/22941932-00000034 SN - 0928-1541 (Print) SN - 2294-1932 (Online) VL - 34 IS - 4 SP - 425 EP - 432 PB - Brill CY - Leiden ER - TY - JOUR A1 - Stojnic, Srdjan A1 - Sass-Klaassen, Ute G. M. A1 - Orlovic, Sasa A1 - Matovic, Bratislav A1 - Eilmann, Britta T1 - Plastic growth response of European beech provenances to dry site conditions T2 - IAWA Journal / International Association of Wood Anatomists Y1 - 2013 U6 - https://doi.org/10.1163/22941932-00000038 SN - 0928-1541 (Print) SN - 2294-1932 (Online) VL - 34 IS - 4 SP - 475 EP - 484 PB - Brill CY - Leiden ER - TY - JOUR A1 - Lévesque, Mathieu A1 - Saurer, Matthias A1 - Siegwolf, Rolf A1 - Eilmann, Britta A1 - Brang, Peter A1 - Bugmann, Harald A1 - Rigling, Andreas T1 - Drought response of five conifer species under contrasting water availability suggests high vulnerability of Norway spruce and European larch JF - Global Change Biology Y1 - 2013 U6 - https://doi.org/10.1111/gcb.12268 SN - 1365-2486 (Online) SN - 1354-1013 (Print) VL - 19 IS - 10 SP - 3184 EP - 3199 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Rigling, Andreas A1 - Bigler, Christof A1 - Eilmann, Britta A1 - Feldmeyer-Christe, Elisabeth A1 - Gimmi, Urs A1 - Ginzler, Christian A1 - Graf, Ulrich A1 - Mayer, Phillip A1 - Vacchiano, Giorgio A1 - Weber, Pascal A1 - Wohlgemuth, Thomas A1 - zweifel, Roman A1 - Dobbertin, Matthias T1 - Driving factors of a vegetation shift from Scots pine to pubescent oak in dry Alpine forests JF - Global Change Biology N2 - An increasing number of studies have reported on forest declines and vegetation shifts triggered by drought. In the Swiss Rhone valley (Valais), one of the driest inner-Alpine regions, the species composition in low elevation forests is changing: The sub-boreal Scots pine (Pinus sylvestris L.) dominating the dry forests is showing high mortality rates. Concurrently the sub-Mediterranean pubescent oak (Quercus pubescens Willd.) has locally increased in abundance. However, it remains unclear whether this local change in species composition is part of a larger-scale vegetation shift. To study variability in mortality and regeneration in these dry forests we analysed data from the Swiss national forest inventory (NFI) on a regular grid between 1983 and 2003, and combined it with annual mortality data from a monitoring site. Pine mortality was found to be highest at low elevation (below 1000 m a.s.l.). Annual variation in pine mortality was correlated with a drought index computed for the summer months prior to observed tree death. A generalized linear mixed-effects model indicated for the NFI data increased pine mortality on dryer sites with high stand competition, particularly for small-diameter trees. Pine regeneration was low in comparison to its occurrence in the overstorey, whereas oak regeneration was comparably abundant. Although both species regenerated well at dry sites, pine regeneration was favoured at cooler sites at higher altitude and oak regeneration was more frequent at warmer sites, indicating a higher adaptation potential of oaks under future warming. Our results thus suggest that an extended shift in species composition is actually occurring in the pine forests in the Valais. The main driving factors are found to be climatic variability, particularly drought, and variability in stand structure and topography. Thus, pine forests at low elevations are developing into oak forests with unknown consequences for these ecosystems and their goods and services. Y1 - 2012 U6 - https://doi.org/10.1111/gcb.12038 SN - 1354-1013 (Print) SN - 1365-2486 (Online) VL - 19 IS - 1 SP - 229 EP - 240 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Egli, Simon A1 - Ayer, François A1 - Peter, Martina A1 - Eilmann, Britta A1 - Rigling, Andreas T1 - Is forest mushroom productivity driven by tree growth? Results from a thinning experiment JF - Annals of Forest Science N2 - • 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 Chanéaz, 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. Y1 - 2010 U6 - https://doi.org/10.1051/forest/2010011 SN - 1286-4560 (Print) SN - 1297-966X (Online) VL - 67 IS - 5 SP - 509 PB - Springer CY - Paris ER - TY - JOUR A1 - Eilmann, Britta A1 - Dobbertin, Matthias A1 - Rigling, Andreas T1 - Growth response of Scots pine with different crown transparency status to drought release JF - Annals of Forest Science Y1 - 2013 U6 - https://doi.org/10.1007/s13595-013-0310-z SN - 1286-4560 (Print) SN - 1297-966X (Online) VL - 70 IS - 7 SP - 685 EP - 693 PB - Springer CY - Cham ER - TY - JOUR A1 - Fonti, Patrick A1 - von Arx, Georg A1 - García-González, Ignacio A1 - Eilmann, Britta A1 - Sass-Klaassen, Ute G. W. A1 - Gärtner, Holger A1 - Eckstein, Dieter T1 - Studying global change through investigation of the plastic responses of xylem anatomy in tree rings JF - New Phytologist N2 - Variability in xylem anatomy is of interest to plant scientists because of the role water transport plays in plant performance and survival. Insights into plant adjustments to changing environmental conditions have mainly been obtained through structural and functional comparative studies between taxa or within taxa on contrasting sites or along environmental gradients. Yet, a gap exists regarding the study of hydraulic adjustments in response to environmental changes over the lifetimes of plants. In trees, dated tree-ring series are often exploited to reconstruct dynamics in ecological conditions, and recent work in which wood-anatomical variables have been used in dendrochronology has produced promising results. Environmental signals identified in water-conducting cells carry novel information reflecting changes in regional conditions and are mostly related to short, sub-annual intervals. Although the idea of investigating environmental signals through wood anatomical time series goes back to the 1960s, it is only recently that low-cost computerized image-analysis systems have enabled increased scientific output in this field. We believe that the study of tree-ring anatomy is emerging as a promising approach in tree biology and climate change research, particularly if complemented by physiological and ecological studies. This contribution presents the rationale, the potential, and the methodological challenges of this innovative approach. Y1 - 2010 U6 - https://doi.org/10.1111/j.1469-8137.2009.03030.x SN - 1469-8137 (Online) SN - 0028-646X (Print) VL - 185 IS - 1 SP - 42 EP - 53 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Lévesque, Mathieu A1 - Siegwolf, Rolf A1 - Eilmann, Britta A1 - Saurer, Matthias A1 - Rigling, Andreas T1 - Increased water-use efficiency does not lead to enhanced tree growth under xeric and mesic conditions JF - New Phytologist Y1 - 2014 U6 - https://doi.org/10.1111/nph.12772 SN - 1469-8137 (Online) SN - 0028-646X (Print) VL - 203 IS - 1 SP - 94 EP - 109 PB - Wiley-Blackwell CY - Oxford ER - TY - JOUR A1 - Eilmann, Britta A1 - Zweifel, Roman A1 - Buchmann, Nina A1 - Fonti, Patrick A1 - Rigling, Andreas T1 - Drought-induced adaptation of the xylem in Scots pine and pubescent oak JF - Tree Physiology Y1 - 2009 U6 - https://doi.org/10.1093/treephys/tpp035 SN - 0829-318X (Print) SN - 1758-4469 (Online) VL - 29 IS - 8 SP - 1011 EP - 1020 PB - Heron CY - Victoria, BC ER - TY - JOUR A1 - Dobbertin, Matthias A1 - Eilmann, Britta A1 - Bleuler, Peter A1 - Giuggiola, Arnaud A1 - Graf Pannatier, Elisabeth A1 - Landolt, Werner A1 - Schleppi, Patrick A1 - Rigling, Andreas T1 - Effect of irrigation on needle morphology, shoot and stem growth in a drought-exposed Pinus sylvestris forest JF - Tree Physiology N2 - 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. Y1 - 2010 U6 - https://doi.org/10.1093/treephys/tpp123 SN - 1758-4469 (Online) SN - 0829-318X (Print) VL - 30 IS - 3 SP - 346 EP - 360 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Rigling, Andreas A1 - Eilmann, Britta A1 - Koechli, Roger A1 - Dobbertin, Matthias T1 - Mistletoe-induced crown degradation in Scots pine in a xeric environment N2 - Increasing Scots pine (Pinus sylvestris L.) mortality has been recently observed in the dry inner valleys of the European Alps. Besides drought, infection with pine mistletoe (Viscum album ssp. austriacum) seems to play an important role in the mortality dynamics of Scots pines, but how mistletoes promote pine decline remains unclear. To verify whether pine mistletoe infection weakens the host via crown degradation, as observed for dwarf mistletoes, we studied the negative effects of pine mistletoe infestation on the photosynthetic tissues and branch growth of pairs of infested and non-infested branches. Pine mistletoe infection leads to crown degradation in its host by reducing the length, the radial increment, the ramification, the needle length and the number of needle years of the infested branches. This massive loss in photosynthetic tissue results in a reduction in primary production and a subsequent decrease in carbohydrate availability. The significant reduction in needle length due to mistletoe infection is an indication for a lower water and nutrient availability in infested branches. Thus, mistletoe infection might lead to a decrease in the availability of water and carbohydrates, the two most important growth factors, which are already shortened due to the chronic drought situation in the area. Therefore, pine mistletoe increases the risk of drought-induced mortality of its host when growing in a xeric environment. Y1 - 2010 U6 - https://doi.org/10.1093/treephys/tpq038 SN - 1758-4469 (Online) SN - 0829-318X (Print) VL - 30 IS - 7 SP - 845 EP - 832 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Eilmann, Britta A1 - Rigling, Andreas ED - Abrams, Marc T1 - Tree-growth analyses to estimate tree species' drought tolerance JF - Tree Physiology N2 - Climate change is challenging forestry management and practices. Among other things, tree species with the ability to cope with more extreme climate conditions have to be identified. However, while environmental factors may severely limit tree growth or even cause tree death, assessing a tree species' potential for surviving future aggravated environmental conditions is rather demanding. The aim of this study was to find a tree-ring-based method suitable for identifying very drought-tolerant species, particularly potential substitute species for Scots pine (Pinus sylvestris L.) in Valais. In this inner-Alpine valley, Scots pine used to be the dominating species for dry forests, but today it suffers from high drought-induced mortality. We investigate the growth response of two native tree species, Scots pine and European larch (Larix decidua Mill.), and two non-native species, black pine (Pinus nigra Arnold) and Douglas fir (Pseudotsuga menziesii Mirb. var. menziesii), to drought. This involved analysing how the radial increment of these species responded to increasing water shortage (abandonment of irrigation) and to increasingly frequent drought years. Black pine and Douglas fir are able to cope with drought better than Scots pine and larch, as they show relatively high radial growth even after irrigation has been stopped and a plastic growth response to drought years. European larch does not seem to be able to cope with these dry conditions as it lacks the ability to recover from drought years. The analysis of trees' short-term response to extreme climate events seems to be the most promising and suitable method for detecting how tolerant a tree species is towards drought. However, combining all the methods used in this study provides a complete picture of how water shortage could limit species. Y1 - 2012 U6 - https://doi.org/10.1093/treephys/tps004 SN - 0829-318X (Print) SN - 1758-4469 (Online) VL - 32 IS - 2 SP - 178 EP - 187 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Eilmann, Britta A1 - Sterck, Frank J. A1 - Wegner, L. A1 - de Vries, Sven M. G. A1 - von Arx, G. A1 - Mohren, Godefridus M. J. A1 - den Ouden, Jan A1 - Sass-Klaassen, Ute G. W. T1 - Wood structural differences between northern and southern beech provenances growing at a moderate site JF - Tree Physiology Y1 - 2014 U6 - https://doi.org/10.1093/treephys/tpu069 SN - 1758-4469 (Online) SN - 0829-318X (Print) VL - 34 IS - 8 SP - 882 EP - 893 PB - Oxford University Press CY - Oxford ER - TY - JOUR A1 - Eilmann, Britta A1 - de Vries, Sven M. G. A1 - den Ouden, Jan A1 - Mohren, Godefridus M. J. A1 - Sauren, Pascal A1 - Sass-Klaassen, Ute G. W. T1 - Origin matters! Difference in drought tolerance and productivity of coastal Douglas-fir (Pseudotsuga menziesii (Mirb.)) provenances JF - Forest Ecology and Management Y1 - 2013 U6 - https://doi.org/doi:10.1016/j.foreco.2013.03.031 SN - 1872-7042 (Online) SN - 0378-1127 (Print) VL - 2013 IS - 302 SP - 133 EP - 143 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Weemstra, Monique A1 - Eilmann, Britta A1 - Sass-Klaassen, Ute G. W. A1 - Sterck, Frank J. T1 - Summer droughts limit tree growth across 10 temperate species on a productive forest site JF - Forest Ecology and Management Y1 - 2013 U6 - https://doi.org/doi:10.1016/j.foreco.2013.06.007 SN - 0378-1127 (Print) SN - 1872-7042 (Online) VL - 2013 IS - 306 SP - 142 EP - 149 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Feichtinger, Linda M. A1 - Eilmann, Britta A1 - Buchmann, Nina A1 - Rigling, Andreas T1 - Growth adjustments of conifers to drought and to century-long irrigation JF - Forest Ecology and Management N2 - Our knowledge on tree responses to drought is mainly based on short-term manipulation experiments which do not capture any possible long-term adjustments in this response. Therefore, historical water channels in inner-Alpine dry valleys were used as century-long irrigation experiments to investigate adjustments in tree growth to contrasting water supply. This involved quantifying the tree-ring growth of irrigated and non-irrigated (control) Scots pine (Pinus sylvestris L.) in Valais (Switzerland), as well as European larch (Larix decidua Mill.) and black pine (Pinus nigra Arnold) in Vinschgau (Italy). Furthermore, the adjustments in radial growth of Scots pine and European larch to an abrupt stop in irrigation were analyzed. Irrigation promoted the radial growth of all tree species investigated compared to the control: (1) directly through increased soil water availability, and (2) indirectly through increased soil nutrients and humus contents in the irrigated plots. Irrigation led to a full elimination of growth responses to climate for European larch and black pine, but not for Scots pine, which might become more sensitive to drought with increasing tree size in Valais. For the control trees, the response of the latewood increment to water availability in July/August has decreased in recent decades for all species, but increased in May for Scots pine only. The sudden irrigation stop caused a drop in radial growth to a lower level for Scots pine or similar level for larch compared to the control for up to ten years. However, both tree species were then able to adjust to the new conditions and subsequently grew with similar (Scots pine) or even higher growth rates (larch) than the control. To estimate the impact of climate change on future forest development, the duration of manipulation experiments should be on longer time scales in order to capture adjustment processes and feedback mechanisms of forest ecosystems. Y1 - 2014 U6 - https://doi.org/10.1016/j.foreco.2014.08.008 SN - 1872-7042 (Online) SN - 0378-1127 (Print) VL - 2014 IS - 334 SP - 96 EP - 105 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Leandro, J. A1 - Bung, Daniel Bernhard A1 - Carvalho, R. T1 - Measuring void fraction and velocity fields of a stepped spillway for skimming flow using non-intrusive methods JF - Experiments in fluids Y1 - 2014 U6 - https://doi.org/10.1007/s00348-014-1732-6 SN - 0723-4864 (Print) ; 1432-1114 (Online) IS - 55 SP - Art. 1732 PB - Springer Nature CY - Heidelberg ER - TY - JOUR A1 - Ratke, Lorenz A1 - Milow, Barbara A1 - Lisinski, Susanne A1 - Hoepfner, Sandra T1 - On an effect of fine ceramic particles on the structure of aerogels JF - Microgravity science and technology Y1 - 2014 U6 - https://doi.org/10.1007/s12217-014-9380-2 SN - 0938-0108 ; 1875-0494 VL - 26 SP - 103 EP - 110 PB - Springer Nature CY - Heidelberg ER - TY - JOUR A1 - Almajhdi, Fahad N. A1 - Senger, Tilo A1 - Amer, Haitham M. A1 - Gissmann, Lutz A1 - Öhlschläger, Peter T1 - Design of a highly effective therapeutic HPV16 E6/E7-specific DNA vaccine: optimization by different ways of sequence rearrangements (Shuffling) JF - PLOS one N2 - Persistent infection with the high-risk Human Papillomavirus type 16 (HPV 16) is the causative event for the development of cervical cancer and other malignant tumors of the anogenital tract and of the head and neck. Despite many attempts to develop therapeutic vaccines no candidate has entered late clinical trials. An interesting approach is a DNA based vaccine encompassing the nucleotide sequence of the E6 and E7 viral oncoproteins. Because both proteins are consistently expressed in HPV infected cells they represent excellent targets for immune therapy. Here we report the development of 8 DNA vaccine candidates consisting of differently rearranged HPV-16 E6 and E7 sequences within one molecule providing all naturally occurring epitopes but supposedly lacking transforming activity. The HPV sequences were fused to the J-domain and the SV40 enhancer in order to increase immune responses. We demonstrate that one out of the 8 vaccine candidates induces very strong cellular E6- and E7- specific cellular immune responses in mice and, as shown in regression experiments, efficiently controls growth of HPV 16 positive syngeneic tumors. This data demonstrates the potential of this vaccine candidate to control persistent HPV 16 infection that may lead to malignant disease. It also suggests that different sequence rearrangements influence the immunogenecity by an as yet unknown mechanism. Y1 - 2014 U6 - https://doi.org/10.1371/journal.pone.0113461 SN - 1932-6203 VL - 11 IS - 9 PB - PLOS CY - San Francisco ER - TY - JOUR A1 - Poghossian, Arshak A1 - Bäcker, Matthias A1 - Mayer, Dirk A1 - Schöning, Michael Josef T1 - Gating capacitive field-effect sensors by the charge of nanoparticle/molecule hybrids JF - Nanoscale Y1 - 2015 U6 - https://doi.org/10.1039/C4NR05987E SN - 2040-3372 (E-Journal); 2040-3364 (Print) SP - 1023 EP - 1031 PB - Royal Society of Chemistry (RSC) CY - Cambridge ER - TY - JOUR A1 - Kluczka, Sven A1 - Eckstein, Julian A1 - Alexopoulos, Spiros A1 - Vaeßen, Christiane A1 - Roeb, Martin T1 - Process simulation for solar steam and dry reforming JF - Energy procedia : Proceedings of the SolarPACES 2013 International Conference N2 - In co-operation with the German Aerospace Center, the Solar-Institut Jülich has been analyzing the different technologies that are available for methanol production from CO2 using solar energy. The aim of the project is to extract CO2 from industrial exhaust gases or directly from the atmosphere to recycle it by use of solar energy. Part of the study was the modeling and simulating of a methane reformer for the production of synthesis gas, which can be operated by solar or hybrid heat sources. The reformer has been simplified in such a way that the model is accurate and enables fast calculations. The developed pseudo-homogeneous one- dimensional model can be regarded as a kind of counter-current heat exchanger and is able to incorporate a steam reforming reaction as well as a dry reforming reaction. Y1 - 2014 U6 - https://doi.org/10.1016/j.egypro.2014.03.092 SN - 1876-6102 (E-Journal) VL - 49 SP - 850 EP - 859 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Müller, Martin A1 - Hirschfeld, Julian A1 - Lambertz, Rita A1 - Schulze Lohoff, Andreas A1 - Lustfeld, Hans A1 - Pfeifer, Heinz A1 - Reißel, Martin T1 - Validation of a novel method for detecting and stabilizing malfunctioning areas in fuel cell stacks JF - Journal of power sources N2 - In this paper a setup for detecting malfunctioning areas of MEAs in fuel cell stacks is described. Malfunctioning areas generate electric cross currents inside bipolar plates. To exploit this we suggest bipolar plates consisting not of two but of three layers. The third one is a highly conducting layer and segmented such that the cross currents move along the segments to the surface of the stack where they can be measured by an inductive sensor. With this information a realistic model can be used to detect the malfunctioning area. Furthermore the third layer will prevent any current inhomogeneity of a malfunctioning cell to spread to neighbouring cells in the stack. In this work the results of measurements in a realistic cell setup will be compared with the results obtained in simulation studies with the same configuration. The basis for the comparison is the reliable characterisation of the electrical properties of the cell components and the implication of these results into the simulation model. The experimental studies will also show the limits in the maximum number of segments, which can be used for a reliable detection of cross currents. Y1 - 2014 U6 - https://doi.org/10.1016/j.jpowsour.2014.08.045 SN - 1873-2755 (E-Journal); 0378-7753 (Print) VL - 272 SP - 225 EP - 232 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Schusser, Sebastian A1 - Poghossian, Arshak A1 - Bäcker, Matthias A1 - Krischer, M. A1 - Leinhos, Marcel A1 - Wagner, P. A1 - Schöning, Michael Josef T1 - An application of field-effect sensors for in-situ monitoring of degradation of biopolymers JF - Sensors and actuators B: Chemical N2 - The characterization of the degradation kinetics of biodegradable polymers is mandatory with regard to their proper application. In the present work, polymer-modified electrolyte–insulator–semiconductor (PMEIS) field-effect sensors have been applied for in-situ monitoring of the pH-dependent degradation kinetics of the commercially available biopolymer poly(d,l-lactic acid) (PDLLA) in buffer solutions from pH 3 to pH 13. PDLLA films of 500 nm thickness were deposited on the surface of an Al–p-Si–SiO2–Ta2O5 structure from a polymer solution by means of spin-coating method. The PMEIS sensor is, in principle, capable to detect any changes in bulk, surface and interface properties of the polymer induced by degradation processes. A faster degradation has been observed for PDLLA films exposed to alkaline solutions (pH 9, pH 11 and pH 13). Y1 - 2015 U6 - https://doi.org/10.1016/j.snb.2014.10.058 SN - 1873-3077 (E-Journal); 0925-4005 (Print) VL - 207, Part B SP - 954 EP - 959 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Konstantinidis, Konstantinos A1 - Flores Martinez, Claudio A1 - Dachwald, Bernd A1 - Ohndorf, Andreas A1 - Dykta, Paul A1 - Bowitz, Pascal A1 - Rudolph, Martin A1 - Digel, Ilya A1 - Kowalski, Julia A1 - Voigt, Konstantin A1 - Förstner, Roger T1 - A lander mission to probe subglacial water on Saturn's moon enceladus for life JF - Acta astronautica Y1 - 2015 SN - 1879-2030 (E-Journal); 0094-5765 (Print) VL - Vol. 106 SP - 63 EP - 89 PB - Elsevier CY - Amsterdam ER -