Non-analytic magnetic field dependence of quasi-particle properties of two-dimensional metals

We show that in a weak external magnetic field H the quasi-particle residue and the renormalized electron Lande factor of two-dimensional Fermi liquids exhibit a non-analytic magnetic field dependence proportional to |H| which is due to electron-electron interactions. We explicitly calculate the corresponding prefactors to second order in the interaction and show that they are determined by low-energy scattering processes involving only momenta close to the Fermi surface. Experimentally, these non-analytic terms can be detected from measurements of the magnetic field dependence of the density of states and the magnetoconductivity.Comment: 11 pages, 5 figure

Integrating Taxonomies into Theory-Based Digital Health Interventions for Behavior Change: A Holistic Framework

Digital health interventions have been emerging in the last decade. Due to their interdisciplinary nature, digital health interventions are guided and influenced by theories (e.g., behavioral theories, behavior change technologies, persuasive technology) from different research communities. However, digital health interventions are always coded using various taxonomies and reported in insufficient perspectives. The inconsistency and incomprehensiveness will bring difficulty for conducting systematic reviews and sharing contributions among communities. Based on existing related work, therefore, we propose a holistic framework that embeds behavioral theories, behavior change technique (BCT) taxonomy, and persuasive system design (PSD) principles. Including four development steps, two toolboxes, and one workflow, our framework aims to guide digital health intervention developers to design, evaluate, and report their work in a formative and comprehensive way

Near Field Communication - Its adoption process and technology acceptance

NFC was often predicted in media as well as academic literature to become a de facto standard, which offers great value. Today there are more smartphones than personal computers and tab-lets combined, predicting that the mobile payment market to grow radically. NFC is often cited as a suitable technology for mobile payment solutions. This thesis aims to answer the research question why NFC has not become a standard for mobile payments as well as widely used and accepted. To answer this, we propose a research model based on extended TAM. Our findings suggest that there is a general positive attitude towards NFC, but the participants tend to lack awareness of its existence. In order to complement the findings of our research model, we dis-cuss the adoption process and value of standardization. We also conclude that Apple has a con-siderable share of the smartphone market and that they will play a key role for the future of NFC with whether or not the next generation of their products will support it. Furthermore, it is clear from historical examples that in the end, it will be the users that decide whether or not NFC will be the de facto standard for mobile payments