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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. Neutron-, proton-, and gamma-irradiated p-type pad silicon detectors up to equivalent fluences of about 7 × 1015 neq/cm2 and a dose of 186 Mrad are investigated to study irradiation-induced effects on the TPA-TCT. Neutron and proton irradiation lead to additional linear absorption, which does not occur in gamma-irradiated detectors. The additional absorption is related to cluster damage, and the absorption scales according to the non-ionising energy loss. The influence of irradiation on the two-photon absorption coefficient is investigated, as well as potential laser beam depletion by the irradiation-induced linear absorption. Further, the electric field in neutron- and proton-irradiated pad detectors at an equivalent fluence of about 7 × 1015 neq/cm2 is investigated, where the space charge of the proton-irradiated devices appears inverted compared to the neutron-irradiated device.

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The 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. g., in Germany there has been a huge discussion on potential privacy issues of the app. Thus, we analyze effects of privacy concerns regarding the CWA, perceived CWA benefits, and trust in the German healthcare system to answer why citizens use the CWA. In our initial conference publication at ICT Systems Security and Privacy Protection - 37th IFIP TC 11 International Conference, SEC 2022, we used a sample with 1752 actual users and non-users of the CWA and and support for the privacy calculus theory, i. e., individuals weigh privacy concerns and benefits in their use decision. Thus, citizens privacy perceptions about health technologies (e. g., shaped by public debates) are crucial as they can hinder adoption and negatively affect future fights against pandemics. In this special issue, we adapt our previous work by conducting a second survey 10 months after our initial study with the same pool of participants (830 participants from the first study participated in the second survey). The goal of this longitudinal study is to assess changes in the perceptions of users and non-users over time and to evaluate the influence of the significantly lower hospitalization and death rates on the use behavior which we could observe during the second survey. Our results show that the privacy calculus is relatively stable over time. The only relationship which significantly changes over time is the effect of privacy concerns on the use behavior which significantly decreases over time, i. e., privacy concerns have a lower negative effect one the CWA use indicating that it did not play such an important role in the use decision at a later point in time in the pandemic. We contribute to the literature by introducing one of the rare longitudinal analyses in the literature focusing on the privacy calculus and changes over time in the relevant constructs as well as the relationships between the calculus constructs and target variables (in our case use behavior of a contact tracing app). We can see that the explanatory power of the privacy calculus model is relatively stable over time even if strong externalities might affect individual perceptions related to the model.

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BACKGROUND: 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. METHODS: We conducted a longitudinal survey study in Germany with 833 participants in 2 waves to investigate how participants perceive their peer groups' opinion about making use of the German CWA to mitigate the risk of SARS-CoV-2. In addition, we asked whether this perceived opinion, in turn, influences the participants with respect to their own decision to use the CWA. We analyzed these questions with generalized estimating equations. Further, 2 related sample tests were performed to test for differences between users of the CWA and nonusers and between the 2 points in time (wave 1 with the highest death rates observable during the pandemic in Germany versus wave 2 with significantly lower death rates). RESULTS: Participants perceived that peer groups have a positive opinion toward using the CWA, with more positive opinions by the media, family doctors, politicians, and virologists/Robert Koch Institute and a lower, only slightly negative opinion originating from social media. Users of the CWA perceived their peer groups' opinions about using the app as more positive than nonusers do. Furthermore, the perceived positive opinion of the media (P=.001) and politicians (P<.001) was significantly lower in wave 2 compared with that in wave 1. The perceived opinion of friends and family (P<.001) as well as their perceived influence (P=.02) among nonusers toward using the CWA was significantly higher in the latter period compared with that in wave 1. The influence of virologists (in Germany primarily communicated via the Robert Koch Institute) had the highest positive effect on using the CWA (B=0.363, P<.001). We only found 1 decreasing effect of the influence of politicians (B=-0.098, P=.04). CONCLUSIONS: Opinions of peer groups play an important role when it comes to the adoption of the CWA. Our results show that the influence of virologists/Robert Koch Institute and family/friends exerts the strongest effect on participants' decisions to use the CWA while politicians had a slightly negative influence. Our results also indicate that it is crucial to accompany the introduction of such a contact tracing app with explanations and a media campaign to support its adoption that is backed up by political decision makers and subject matter experts.

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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. We analyse the respective factors influencing app adoption based on the health belief model (HBM) with a cross-sectional online study including 1752 participants from Germany. The study was conducted with a certified panel provider from the end of December 2020 to January 2021. This model is primarily known from evaluations of medical treatments, such as breast cancer screenings, but it was rarely applied in prior work for a health-related information system such as the CWA. Our results indicate that intrinsic and extrinsic motivation to use the CWA are the strongest drivers of app use. In contrast, technical barriers, privacy concerns and lower income are the main inhibitors. Our findings contribute to the literature on the adoption of contact tracing apps by questioning actual users and non-users of the CWA, and we provide valuable insights for policymakers regarding influences of adoption and potential user groups of disease prevention technologies in times of pandemics.

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The 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. Additionally, the mirror technique is introduced, which exploits reflection at a metallised back side to enable the measurement directly below a top metallisation while illuminating from the top.

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A 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 10p J, variation of the pulse repetition rate from 8.2 MHz to single shot, and variation of pulse duration between 300 and 600 fs. The validity of the system as an excitation source in the TPA-TCT is demonstrated by measuring spatially resolved excited charge carriers in a silicon detector.

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The 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. Moreover, the promoter is under the control of the negative regulator SNI1 (SUPPRESSOR OF NPR1, INDUCIBLE1). We have recently reported that SNI1-mediated repression of basal promoter activities and NPR1-dependent induction are maintained in a truncated PR-1 promoter that contains sequences between -816 and -573 upstream of the -68 promoter region. In this addendum, we report that the expression characteristics of this truncated PR-1 promoter is changed profoundly when its as-1-like element is replaced by the as-1 element of Cauliflower Mosaic Virus 35S promoter which also contains two TGACG motifs. The resulting chimeric promoter showed high constitutive activity that was independent from SA, NPR1 and SNI1. Thus, the configuration of two TGA binding sites within the PR-1 promoter determines whether NPR1 can induce and whether SNI1 can repress the promoter.

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Systemic 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. In addition, the promoter is under the control of two proteins that do not directly contact the DNA: the positive regulator NONEXPRESSOR OF PR GENES1 (NPR1), which physically interacts with TGA factors, and the repressor SUPPRESSOR OF NPR1, INDUCIBLE1 (SNI1). In this study, we analyzed the importance of the TGA-binding sites LS5 and LS7 and the WKRY box LS4 for regulation by NPR1 and SNI1. In the absence of LS5 and LS7, NPR1 activates the PR-1 promoter through a mechanism that requires LS4. Since transcriptional activation of WRKY genes is under the control of NPR1 and since LS4 is not sufficient for the activation of a truncated PR-1 promoter by the effector protein NPR1-VP16 in transient assays, it is concluded that the LS4-dependent activation of the PR-1 promoter is indirect. In the case of NPR1 acting directly through TGA factors at its target promoters, two TGA-binding sites are necessary but not sufficient for NPR1 function in transgenic plants and in the NPR-VP16-based trans-activation assay in protoplasts. SNI1 exerts its negative effect in the noninduced state by targeting unknown proteins associated with sequences between bp -816 and -573. Under induced conditions, SNI1 negatively regulates the function of WRKY transcription factors binding to WKRY boxes between bp -550 and -510.

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