The Two-Photon Absorption-Transient Current Technique (TPA-TCT) is a device characterisation technique that enables three-dimensional spatial resolution. Laser light in the quadratic absorption regime is employed to generate excess charge carriers only in a small volume around the focal spot. The drift of the excess charge carriers is studied to obtain information about the device under test.
View Article and Find Full Text PDFThe SARS-CoV-2 pandemic is a pressing societal issue today. The German government promotes a contract tracing app named Corona-Warn-App (CWA), aiming to change citizens' health behaviors during the pandemic by raising awareness about potential infections and enable infection chain tracking. Technical implementations, citizens' perceptions, and public debates around apps differ between countries, e.
View Article and Find Full Text PDFBackground: The German Corona-Warn-App (CWA) is a contact tracing app to mitigate the spread of SARS-CoV-2. As of today, it has been downloaded approximately 45 million times.
Objective: This study aims to investigate the influence of (non)users' social environments on the usage of the CWA during 2 periods with relatively lower death rates and higher death rates caused by SARS-CoV-2.
The World Health Organization declared the emergence of the novel coronavirus (SARS-CoV-2) in January 2020. To trace infection chains, Germany launched its smartphone contact tracing app, the "Corona-Warn-App" (CWA), in June 2020. In order to be successful as a tool for fighting the pandemic, a high adoption rate is required in the population.
View Article and Find Full Text PDFThe two photon absorption-transient current technique (TPA-TCT) was used to investigate a silicon strip detector with illumination from the top. Measurement and analysis techniques for the TPA-TCT of segmented devices are presented and discussed using a passive strip CMOS detector and a standard strip detector as an example. The influence of laser beam clipping and reflection is shown, and a method that allows to compensate these intensity-related effects for investigation of the electric field is introduced and successfully employed.
View Article and Find Full Text PDFA fiber laser system emitting ultrashort femtosecond pulses at 1550 nm with configurable properties has been developed as an excitation source for the two-photon absorption transient current technique (TPA-TCT). The modules of the system are designed to provide the optical specifications required at the output for localized characterization of semiconductor radiation detectors: variation of pulse energy between 10 nJ and 10 , variation of the pulse repetition rate from 8.2 MHz to single shot, and variation of pulse duration between 300 and 600 fs.
View Article and Find Full Text PDFThe plant defense hormone salicylic acid (SA) activates gene expression through a number of different mechanisms. In Arabidopsis thaliana, the SA-induced PATHOGENESIS RELATED (PR)-1 promoter is regulated through TGA transcription factors binding to the two TGACG motifs of the so called as-1 (activation sequence-1)-like element which is located between base pair positions -665 and -641. Activation is mediated by the transcriptional co-activator NPR1 (NON EXPRESSOR OF PR GENES1), which physically interacts with TGA factors.
View Article and Find Full Text PDFSystemic acquired resistance is a broad-spectrum plant immune response involving massive transcriptional reprogramming. The Arabidopsis (Arabidopsis thaliana) PATHOGENESIS-RELATED-1 (PR-1) gene has been used in numerous studies to elucidate transcriptional control mechanisms regulating systemic acquired resistance. WRKY transcription factors and basic leucine zipper proteins of the TGA family regulate the PR-1 promoter by binding to specific cis-elements.
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