172 research outputs found
Drones in Railways
Evidence shows that the applications of drones are increasing quickly in many industries. Railways are no exception. Due to fast advances in technology, drones are on the verge of breakthroughs that will affect future applications, implementations, and their consequences. Looking ahead, we elaborate on the potential for drones in railways. We use scenario planning and combine it with the findings of an action research project, which we conducted with Swiss Federal Railways (SBB). First, we explore the applications and future trends of drone use in railway operations. Second, based on seven identified factors that may affect the future of drones in railways by 2030, we develop three future scenarios: pessimistic, realistic, and optimistic. The study results help practitioners make informed decisions regarding future drone programs in railways. We also contribute theoretical insights into how high-potential technologies can unleash new capabilities in railway operations
Carbon fluxes to the soil in a mature temperate forest assessed by 13C isotope tracing
Photosynthetic carbon uptake and respiratory C release from soil are major components of the global carbon balance. The use of 13C depleted CO2 (δ13C = −30‰) in a free air CO2 enrichment experiment in a mature deciduous forest permitted us to trace the carbon transfer from tree crowns to the rhizosphere of 100-120years old trees. During the first season of CO2 enrichment the CO2 released from soil originated substantially from concurrent assimilation. The small contribution of recent carbon in fine roots suggests a much slower fine root turnover than is often assumed.13C abundance in soil air correlated best with temperature data taken from 4 to 10days before air sampling time and is thus rapidly available for root and rhizosphere respiration. The spatial variability of δ13C in soil air showed relationships to above ground tree types such as conifers versus broad-leaved trees. Considering the complexity and strong overlap of roots from different individuals in a forest, this finding opens an exciting new possibility of associating respiration with different species. What might be seen as signal noise does in fact contain valuable information on the spatial heterogeneity of tree-soil interactio
Konzeption und Evaluation eines Zufriedenheitsfragebogens für Teilnehmende externer universitärer Fortbildungsmaßnahmen
Um dem allgemeinen Bildungsauftrag gerecht zu werden und um neue finanzielle Ressourcen zu erschließen, bieten Universitäten zunehmend auch für Nichtstudierende kostenpflichtige Weiterbildung an. Die vorliegende Untersuchung berichtet von der Erstellung und Analyse eines Zufriedenheitsfragebogens. Aufbauend auf einer Analyse von Fragebögen zu universitären Lehrveranstaltungsevaluationen wird ein Instrument entwickelt, bei dem auf zwei Skalen die Zufriedenheit mit dem Dozenten sowie mit dem Seminar erfragt werden. Beide Skalen erweisen sich nach Antwortanalyse der Teilnehmenden aus 15 Veranstaltungen mit einer Reliabilität von über .85 und korrigierten Itemtrennschärfen von über .60 als messgenau. Eine Regression der Gesamtzufriedenheit auf die beiden Skalen erweist sich als signifikant und erklärt über 70% der Varianz des Kriteriums. Unterschiedliche Reihenfolgebedingungen des
Fragebogens ergeben keine systematischen Unterschiede
Double waveguide couplers produced by simultaneous femtosecond writing
We report on a novel method to create waveguide coupler devices in fused silica by combining the technique of beam shaping with femtosecond laser writing. The method is based on a programmable phase modulator and a dynamic variation of the phase-pattern during the writing process. The major advantage is the possibility to create complex devices in a single sweep by simultaneously writing two or more waveguides with changing separation. The guiding properties and the coupling behavior between the waveguides are investigated
Blühstreifen für Bestäuber und andere Nützlinge - Wertvolle Nahrungsquellen im Ackerbau
Das Merkblatt hilft Beratungskräften, Landwirtinnen und Landwirten sowie weiteren landwirtschaftlichen Akteuren bei der Umsetzung der neuen Biodiversitätsförderfläche Blühstreifen für Bestäuber und andere Nützlinge. Das Dokument beschreibt den kulturspezifischen Nutzen der Flächen, deren Anlage, Pflege und Aufhebung.
Zudem werden Empfehlungen zur optimalen Umsetzung formuliert, damit die erwartete Leistung der Bestäuber und Nützlinge auch langfristig erbracht werden kann
Biotechnological Potential of Bacteria Isolated from the Sea Cucumber Holothuria leucospilota and Stichopus vastus from Lampung, Indonesia
In order to minimize re-discovery of already known anti-infective compounds, we focused our screening approach on understudied, almost untapped marine environments including marine invertebrates and their associated bacteria. Therefore, two sea cucumber species, Holothuria leucospilota and Stichopus vastus, were collected from Lampung (Indonesia), and 127 bacterial strains were identified by partial 16S rRNA-gene sequencing analysis and compared with the NCBI database. In addition, the overall bacterial diversity from tissue samples of the sea cucumbers H. leucospilota and S. vastus was analyzed using the cultivation-independent Illumina MiSEQ analysis. Selected bacterial isolates were grown to high densities and the extracted biomass was tested against a selection of bacteria and fungi as well as the hepatitis C virus (HCV). Identification of putative bioactive bacterial-derived compounds were performed by analyzing the accurate mass of the precursor/parent ions (MS1) as well as product/daughter ions (MS2) using high resolution mass spectrometry (HRMS) analysis of all active fractions. With this attempt we were able to identify 23 putatively known and two previously unidentified precursor ions. Moreover, through 16S rRNA-gene sequencing we were able to identify putatively novel bacterial species from the phyla Actinobacteria, Proteobacteria and also Firmicutes. Our findings suggest that sea cucumbers like H. leucospilota and S. vastus are promising sources for the isolation of novel bacterial species that produce compounds with potentially high biotechnological potential
Characterization and optimization of laser-generated THz beam for THz based streaking
At the Ferninfrarot Linac- und Test-Experiment (FLUTE) at the Karlsruhe Institute of Technology (KIT) a new and compact method for longitudinal diagnostics of ultrashort electron bunches is being developed. For this technique, which is based on THz streaking, strong electromagnetic pulses with frequencies around 240 GHz are required. Therefore, a setup for laser-generated THz radiation using tilted-pulse-front pumping in lithium niobate was designed, delivering up to 1 µJ of THz pulse energy with a conversion efficiency of up to 0.03 %. In this contribution we study the optimization of the THz beam transport and environment
Prospective evaluation of quality of life effects in patients undergoing palliative radiotherapy for brain metastases
Background: Recently published results of quality of life (QoL) studies indicated different outcomes of palliative radiotherapy for brain metastases. This prospective multi-center QoL study of patients with brain metastases was designed to investigate which QoL domains improve or worsen after palliative radiotherapy and which might provide prognostic information. Methods: From 01/2007-01/2009, n=151 patients with previously untreated brain metastases were recruited at 14 centers in Germany and Austria. Most patients (82 %) received whole-brain radiotherapy. QoL was measured with the EORTC-QLQ-C15-PAL and brain module BN20 before the start of radiotherapy and after 3 months. Results: At 3 months, 88/142 (62 %) survived. Nine patients were not able to be followed up. 62 patients (70.5 % of 3-month survivors) completed the second set of questionnaires. Three months after the start of radiotherapy QoL deteriorated significantly in the areas of global QoL, physical function, fatigue, nausea, pain, appetite loss, hair loss, drowsiness, motor dysfunction, communication deficit and weakness of legs. Although the use of corticosteroid at 3 months could be reduced compared to pre-treatment (63 % vs. 37 %), the score for headaches remained stable. Initial QoL at the start of treatment was better in those alive than in those deceased at 3 months, significantly for physical function, motor dysfunction and the symptom scales fatigue, pain, appetite loss and weakness of legs. In a multivariate model, lower Karnofsky performance score, higher age and higher pain ratings before radiotherapy were prognostic of 3-month survival. Conclusions: Moderate deterioration in several QoL domains was predominantly observed three months after start of palliative radiotherapy for brain metastases. Future studies will need to address the individual subjective benefit or burden from such treatment. Baseline QoL scores before palliative radiotherapy for brain metastases may contain prognostic information
The phylogenetic landscape and nosocomial spread of the multidrug-resistant opportunist Stenotrophomonas maltophilia
Recent studies portend a rising global spread and adaptation of human- or healthcare-associated pathogens. Here, we analyse an international collection of the emerging, multidrug-resistant, opportunistic pathogen Stenotrophomonas maltophilia from 22 countries to infer population structure and clonality at a global level. We show that the S. maltophilia complex is divided into 23 monophyletic lineages, most of which harbour strains of all degrees of human virulence. Lineage Sm6 comprises the highest rate of human-associated strains, linked to key virulence and resistance genes. Transmission analysis identifies potential outbreak events of genetically closely related strains isolated within days or weeks in the same hospitals
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