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The longitudinal and transverse nuclear magnetic resonance relaxivity dispersion (NMRD) of 1H in water induced by the paramagnetic relaxation enhancement (PRE) of dissolved lanthanide ions (Ln3+) can become very strong. Longitudinal and transverse 1H NMRD for Gd3+, Dy3+, Er3+ and Ho3+ were measured from 20 MHz/0.47 T to 1382 MHz/32.5 T, which extended previous studies by a factor of more than two in the frequency range. For the NMRD above 800 MHz, we used a resistive magnet, which exhibits reduced field homogeneity and stability in comparison to superconducting and permanent NMR magnets. These drawbacks were addressed by dedicated NMRD methods. In a comparison of NMRD measurements between 800 MHz and 950 MHz performed in both superconducting and resistive magnets, it was found that the longitudinal relaxivities were almost identical. However, the magnetic field fluctuations of the resistive magnet strongly perturbed the transverse relaxation. The longitudinal NMRDs are consistent with previous work up to 600 MHz. The transverse NMRD nearly scales with the longitudinal one with a factor close to one. The data can be interpreted within a PRE model that comprises the dipolar hyperfine interactions between the 1H and the paramagnetic ions, as well as a Curie spin contribution that is dominant at high magnetic fields for Dy3+, Er3+ and Ho3+. Our findings provide a solid methodological basis and valuable quantitative insights for future high-frequency NMRD studies, enhancing the measurement accuracy and applicability of PRE models for paramagnetic ions in aqueous solutions. [ABSTRACT FROM AUTHOR]

This article explores the phenomenon of block talk among Germanspeaking Twitter users, based on a subsample of 1700 tweets from a larger corpus of 380,000 block-related tweets collected between February and December 2021. Block talk refers to users publicly mentioning and conversing about the disconnective practice of blocking, which sometimes stimulates a debate about the legitimate use of blocking while at other times providing an outgroup marker for collective positioning. Through the example of block talk we demonstrate that the platform's curatorial infrastructure for drawing boundaries between public and private is continuously negotiated, and that this negotiation transforms the meaning of some of the default communicative affordances of the platform but also creates its own routines of making public. On the one hand, we show how users adapt conversational devices such as hashtags, screenshots, and @-mentions in the context of block talk. On the other hand, we present examples of Twitter users' normative reflections about blocking and discuss them as processes of metapragmatic enregisterment. In the final discussion, we propose to integrate processes of routinized adaptation as well as reflexive enregisterment into a joint process of 'communicative infrastructuring'. [ABSTRACT FROM AUTHOR]

Background: The simultaneous implantation of the Bonebridge (MED-EL, Innsbruck, Austria), a semi-implantable active transcutaneous bone conduction hearing device and anchors for auricular prostheses can be challenging as both implants contain magnets and compete for the narrow space in the designated implantation area. Material and methods: A preoperative planning tool (virtual surgery) was used with individual 3D computer models of the skull and implants for finding optimal implant positions for both the floating mass transducer (FMT) and the anchors for the auricular prosthesis. The interaction between the magnetic prosthesis anchors and the FMT was measured by means of static magnetic forces. A retrospective data analysis was conducted to evaluate the surgical and audiological outcome. Results: Between 2014 and 2021, a 3D planning of a simultaneous implantation of the Bonebridge with auricular prosthesis anchors was conducted on 6 ears of 5 patients (3 males, 2 females; age range 17–56 years). The individual preoperative planning was considered very useful for the optimal placement of bone anchors in combination with the Bonebridge. Audiological data showed a clear benefit for hearing 3 months and > 11 months after implantation. No adverse interactions between the magnetic prosthesis anchors and the FMT were observed. In two patients, revision surgery was carried out due to skin inflammation or wound healing problems. No long-term complications were observed 3–5 years after surgery. Conclusion: Preoperative 3D planning represents a clear benefit for the simultaneous audiological and esthetic rehabilitation using the Bonebridge and anchors for auricular prostheses. [ABSTRACT FROM AUTHOR]

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