11 research outputs found
On the computation of -flat outputs for differential-delay systems
We introduce a new definition of -flatness for linear differential delay
systems with time-varying coefficients. We characterize - and -0-flat
outputs and provide an algorithm to efficiently compute such outputs. We
present an academic example of motion planning to discuss the pertinence of the
approach.Comment: Minor corrections to fit with the journal versio
Persistent organic pollutants in shallow percolated water of the Alps Karst system (Zugspitze summit, Germany).
In the German Calcareous Alps at the Zugspitze, percolated water close to a permafrost bedrock in a tunnel system was monitored long-term for polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF), polychlorinated biphenyls (PCB), polycyclic aromatic hydrocarbons (PAH), and 28 organochlorine pesticides (OCP). Semi-permeable membrane devices (SPMD) were deployed in a temporary surface water system at the Zugspitze plateau and analysed for PCB, PAH, and OCP. The high-volume water sampling was successfully implemented and all compounds were identified in the water percolated through the Karst system. However, the percentage distribution of contaminants in the percolated water differed significantly from that found in surface waters. The highest chlorinated PCDD homologues were the predominant compounds of the PCDD/F family, whereas percentages of PCB #52 increased in percolated water. Toxic equivalent values (TEQ) of samples ranged from 2.0 to 4.2pgTEQ/m3 and from 0.017 to 0.069pgTEQ/m3 for PCDD/F and PCB, respectively. Low and intermediate molecular weight PAH were the prevailing compounds in the samples. Endosulfan sulfate, endrin, and cis-heptachlor epoxide were enhanced after water percolation through the Karst system in comparison with the surface waters (wet deposition). The relative enrichment on these pesticides was related to the environmental bedrock conditions and glacier melting sources. In summary, the Karst system highly influenced the fate of organic persistent pollutants generating different chemical patterns in their percolated waters than those found at the surface systems
Sniffing fungi – phenotyping of volatile chemical diversity in <em>Trichoderma </em>species.
Volatile organic compounds (VOCs) play vital roles in the interaction of fungi with plants and other organisms. A systematic study of the global fungal VOC profiles is still lacking, though it is a prerequisite for elucidating the mechanisms of VOC-mediated interactions. Here we present a versatile system enabling a high-throughput screening of fungal VOCs under controlled temperature. In a proof-of-principle experiment, we characterized the volatile metabolic fingerprints of four Trichoderma spp. over a 48 h growth period. The developed platform allows automated and fast detection of VOCs from up to 14 simultaneously growing fungal cultures in real time. The comprehensive analysis of fungal odors is achieved by employing proton transfer reaction-time of flight-MS and GC-MS. The data-mining strategy based on multivariate data analysis and machine learning allows the volatile metabolic fingerprints to be uncovered. Our data revealed dynamic, development-dependent and extremely species-specific VOC profiles from the biocontrol genus Trichoderma. The two mass spectrometric approaches were highly complementary to each other, together revealing a novel, dynamic view to the fungal VOC release. This analytical system could be used for VOC-based chemotyping of diverse small organisms, or more generally, for any in vivo and in vitro real-time headspace analysis
Linear motion control with a low-power hydraulic switching converter - Part II: Flatness-based control
Prelude to a Saturday nighter
This thesis pertains to the forgotten women dramatists of the Harlem/New Negro Renaissance of the 1920\u27s and 1930\u27s. It is divided into two parts: Preface and one-act drama. The Preface addresses the problems and issues when researching these women, namely the fact that there is little research devoted solely to their contributions to the movement. Set in the home of Georgia Douglas Johnson in late summer of 1929. Johnson is one of the most prolific women dramatists of the Harlem/New Negro Renaissance, whose works expanded even into the Civil Rights Movement, the one-act drama consists of a meeting between Johnson and Zora Neale Hurston, who is most notable for her non-dramatic works, despite the fact that it was in drama that she first made her mark. The first scene, set in the parlor, attends to the issue of race and how each woman goes about addressing their own representation of how race affects the African American community. In the second scene, the women are in the kitchen and address the most pressing issue of gender relations within the African American community
Systemic acquired resistance networks amplify airborne defense cues.
Salicylic acid (SA)-mediated innate immune responses are activated in plants perceiving volatile monoterpenes. Here, we show that monoterpene-associated responses are propagated in feed-forward loops involving the systemic acquired resistance (SAR) signaling components pipecolic acid, glycerol-3-phosphate, and LEGUME LECTIN-LIKE PROTEIN1 (LLP1). In this cascade, LLP1 forms a key regulatory unit in both within-plant and betweenplant propagation of immunity. The data integrate molecular components of SAR into systemic signaling networks that are separate from conventional, SA-associated innate immune mechanisms. These networks are central to plant-to-plant propagation of immunity, potentially raising SAR to the population level. In this process, monoterpenes act as microbe-inducible plant volatiles, which as part of plant-derived volatile blends have the potential to promote the generation of a wave of innate immune signaling within canopies or plant stands. Hence, plant-to-plant propagation of SAR holds significant potential to fortify future durable crop protection strategies following a single volatile trigger
Ambient air levels of organochlorine pesticides at three high alpine monitoring stations: Trends and dependencies on geographical origin.
Many persistent organic pollutants (POPs) such as organochlorine pesticides (OCPs), which are emitted into air, occur ubiquitously in different environmental compartments worldwide. OCPs are measurable in conspicuous concentrations in the air not only near emission regions but also in background areas, as in the Alps. In the present study, we analyzed OCPs in air samples between 2005 and 2013 at three high Alpine stations (Weißfluhjoch, Switzerland: 2663 m a s l.; Sonnblick, Austria: 3106 m a s l.; and Schneefernerhaus, Germany: 2650 m a s l.). The air concentrations of OCPs at these stations were lower than those in source regions but higher than those in the Arctic region. Concentration differences between sites were found to be relatively small. To distinguish the influences from different European source regions, four filters of low- volume active air samplers were operated alternately according to a trajectory prediction method. Air masses from the northeast (i.e., Bavaria and Eastern Central Europe) and the south (i.e., Mediterranean countries) were characterized by higher concentrations of OCPs (e.g., pentachlorobenzene and hexachlorobenzene) compared with those arriving from the Atlantic Ocean. Additionally, we evaluated the temporal trend of the single compounds; only a few compounds such as endosulfan exhibited a clear decreasing trend