Quantum Zeno effect and the detection of gravitomagnetism

In this work we introduce two experimental proposals that could shed some light upon the inertial properties of intrinsic spin. In particular we will analyze the role that the gravitomagnetic field of the Earth could have on a quantum system with spin 1/2. We will deduce the expression for Rabi transitions, which depend, explicitly, on the coupling between the spin of the quantum system and the gravitomagnetic field of the Earth. Afterwards, the continuous measurement of the energy of the spin 1/2 system is considered, and an expression for the emerging quantum Zeno effect is obtained. Thus, it will be proved that gravitomagnetism, in connection with spin 1/2 systems, could induce not only Rabi transitions but also a quantum Zeno effect.Comment: Essay awarded with an ``honorable mention'' in the Annual Essay Competition of the Gravity Research Foundation for the year 2000, four new references, discussion enlarged, 9 pages. Accepted in International Journal of Modern Physics

Gamification elements on social live streaming service mobile applications

Social live streaming services (SLSSs), a kind of synchronous social networking service, are slowly but surely becoming a part of people’s daily lives. To keep users interested, a wide range of gamification elements are implemented on these services, increasing the user engagement and changing their behavior. This study examined 20 different SLSS mobile applications and the applied gamification elements. A literature review as well as a content analysis were used to find appropriate SLSS apps and game elements. What kind of mechanics can be found on SLSS mobile apps and how many are implemented on each system? On three of the observed apps we could identify all game elements. Chinese SLSS apps are the most gamified ones. On Ustream, no game element is implemented. The game mechanics following others as well as customization are the most often applied; capturing a moment of a stream is the least often implemented

Transcriptome Analysis Reveals Strain-Specific and Conserved Stemness Genes in Schmidtea mediterranea

The planarian Schmidtea mediterranea is a powerful model organism for studying stem cell biology due to its extraordinary regenerative ability mediated by neoblasts, a population of adult somatic stem cells. Elucidation of the S. mediterranea transcriptome and the dynamics of transcript expression will increase our understanding of the gene regulatory programs that regulate stem cell function and differentiation. Here, we have used RNA-Seq to characterize the S. mediterranea transcriptome in sexual and asexual animals and in purified neoblast and differentiated cell populations. Our analysis identified many uncharacterized genes, transcripts, and alternatively spliced isoforms that are differentially expressed in a strain or cell type-specific manner. Transcriptome profiling of purified neoblasts and differentiated cells identified neoblast-enriched transcripts, many of which likely play important roles in regeneration and stem cell function. Strikingly, many of the neoblast-enriched genes are orthologs of genes whose expression is enriched in human embryonic stem cells, suggesting that a core set of genes that regulate stem cell function are conserved across metazoan species