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131.
132.
Zoe Bont Carla Arce Meret Huber Wei Huang Adrien Mestrot Craig J. Sturrock Matthias Erb 《Journal of chemical ecology》2017,43(3):295-306
Foraging behavior of root feeding organisms strongly affects plant-environment-interactions and ecosystem processes. However, the impact of plant chemistry on root herbivore movement in the soil is poorly understood. Here, we apply a simple technique to trace the movement of soil-dwelling insects in their habitats without disturbing or restricting their interactions with host plants. We tagged the root feeding larvae of Melolontha melolontha with a copper ring and repeatedly located their position in relation to their preferred host plant, Taraxacum officinale, using a commercial metal detector. This method was validated and used to study the influence of the sesquiterpene lactone taraxinic acid β-D-glucopyranosyl ester (TA-G) on the foraging of M. melolontha. TA-G is stored in the latex of T. officinale and protects the roots from herbivory. Using behavioral arenas with TA-G deficient and control plants, we tested the impact of physical root access and plant distance on the effect of TA-G on M. melolontha. The larvae preferred TA-G deficient plants to control plants, but only when physical root contact was possible and the plants were separated by 5 cm. Melolontha melolontha showed no preference for TA-G deficient plants when the plants were grown 15 cm apart, which may indicate a trade-off between the cost of movement and the benefit of consuming less toxic food. We demonstrate that M. melolontha integrates host plant quality and distance into its foraging patterns and suggest that plant chemistry affects root herbivore behavior in a plant-density dependent manner. 相似文献
133.
Isabel Medina Lukas Schmitt Viktoria Kapoustina Stephan Scholl Matthias Rädle 《化学,工程师,技术》2019,91(7):1041-1048
An online image analysis method to determine the film thickness in fluids by use of pulsed near infrared LEDs and an NIR camera was developed. This technique offers the possibility to monitor moving fluid layers. In this work the possibilities and limits of the used apparatus are demonstrated with the application example of measurement of the fluid film thickness distribution of water and glycerol in a falling film. 相似文献
134.
Matthias Siemon Olaf Riese Burkhard Forell Dominic Krnung Walter Klein‐Heßling 《火与材料》2019,43(5):497-513
In the context of industrial buildings and power plants, electrical installations and cable trays represent a main fuel load and a potential initial fire source due to possible short circuits or comparable malfunction. Furthermore, a fire can spread from one tray to additional trays mounted above and/or horizontally on one tray. Because of the high significance of cable fires, several research projects have been carried out, investigating the fire behaviour of cables from small‐scale tests, eg, the cone calorimeter, up to large‐scale tests, analysing complete cable tray constructions. The goal of the work presented in this paper is the extension of the knowledge regarding the influence of geometrical parameters like the packing density and tray distance on the burning behaviour and fire spread of cable tray installations. The results are considered, together with test results from the literature, to quantify the main physical parameters describing the burning behaviour. In a next step, the general applicability of these parameters as input data for the parametrization of the source term of numerical simulations is shown. The test results show that the burning behaviour and the fire spreading highly depend on the cable arrangement of the cables on the cable tray, in combination with other boundary conditions. By applying the results as input for a fire simulation, the mass loss rate is considered appropriately. 相似文献
135.
Wearable electronics, sensors, and energy harvesting devices are gaining an ever increasing importance in consumer products. Their success is, however, contingent on the availability of flexible and cost‐effective functional materials. The present paper presents an up‐scaled processing route for 0–3 thick film composites of the ferroelectric polymer polyvinylidenefluoride‐trifluoroethylene and a relaxor ceramic. Different compositions are investigated for pyro‐ and piezoelectric applications. Various samples are produced via tape casting and spin‐coating as freestanding and supported films of up to 600 × 200 mm² and on 150 mm silicon wafers, respectively. The samples are characterized in terms of thickness and roughness reproducibility, mechanical properties, and impedance. It is shown that good reproducibility and quality of the films can be realized. Depending on the application targeted (pyroelectric or piezoelectric), specific compositions together with the suitable poling process are presented. For instance, a composite with 24 vol% ceramic shows highest pyroelectric properties together with lowest piezoelectric thickness coefficient (d33) when poled for pyroelectric applications. On the other hand, a composite with 50 vol% ceramic exhibits a d33 of 100 pm V?1 that is unsurpassed for this type of composites. These properties are advantageous in a large variety of applications, including wearable devices. 相似文献
136.
The atomic scale interaction of solute with a migrating grain boundary has been studied using a binary phase field crystal (PFC) model. This model bridges between atomistic and continuum simulation techniques as it operates on diffusive timescales but at atomistic length scales. For this study, a two-dimensional channel containing two grains separated by a flat grain boundary has been constructed that allows for a channel length on the order of one micrometer. A new formalism has been developed to allow for the application of an external driving pressure for the growth of one grain. These simulations account for solute/grain boundary interactions, resulting in a solute drag effect on the grain boundary motion. The PFC simulations show good agreement with classical solute drag theory, though deviations due to the atomic scale nature of the interface exist. 相似文献
137.
Capillary electrophoresis-mass spectrometry as a powerful tool in clinical diagnosis and biomarker discovery 总被引:4,自引:0,他引:4
Proteome analysis is now emerging as key technology for deciphering biological processes and the discovery of biomarkers for diseases from tissues and body fluids. The complexity and wide dynamic range of protein expression poses a formidable challenge to both peptide separation technologies and mass spectrometry (MS). Here we review the efforts that have been undertaken to date, focussing on capillary electrophoresis coupled to mass spectrometry (CE-MS). We discuss CE-MS from an application point of view evaluating its merits and vices in regard to biomarker discovery and clinical applications. As examples, we present the use of CE-MS for the determination of protein patterns in urine, serum, and other body fluids. Finally, the benefits and limitations of CE-MS for the analysis of proteins in clinical samples are discussed against the background of alternative technologies. 相似文献
138.
Matthias Goebel Markus Clemenz Bart Staels Prof. Dr. Thomas Unger Prof. Dr. Ulrich Kintscher Prof. Dr. Ronald Gust Prof. Dr. 《ChemMedChem》2009,4(3):445-456
Telmisartan was originally designed as an AT1 antagonist but was later also characterized as a selective PPARγ modulator. This study focused on the identification of the essential structural motifs of telmisartan for PPARγ activation activity, elucidating the individual SAR of each different component (shown).
139.
Matthias Hennemann Dr. Arno Friedl Dr. Mario Lobell Dr. Jörg Keldenich Dr. Alexander Hillisch Dr. Timothy Clark Prof. Dr. Andreas H. Göller Dr. 《ChemMedChem》2009,4(4):657-669
CypScore predicts the reactivity of competing positions in the same and different molecules to a variety of cytochrome P450 metabolic reactions on a single reactivity scale.
140.
Christian Müller Dr. Maria Antonia Gomez‐Zurita Frau Dr. Dario Ballinari Dr. Sonia Colombo Dr. Alessandro Bitto Dr. Enzo Martegani Prof. Cristina Airoldi Dr. Anske Stephanie van Neuren Dr. Matthias Stein Dr. Jörg Weiser Dr. Carlo Battistini Dr. Francesco Peri Prof. 《ChemMedChem》2009,4(4):524-528
A panel of new potential Ras ligands was generated by decorating a tricyclic levoglucosenone‐derived scaffold with aromatic moieties. Some members of the panel show in vitro inhibitory activity toward the nucleotide exchange process on Ras and are toxic to some human cancer cell lines.