Geometric Low-Energy Effective Action in a Doubled Spacetime

The ten-dimensional supergravity theory is a geometric low-energy effective theory and the equations of motion for its fields can be obtained from string theory by computing $\beta$ functions. With $d$ compact dimensions, we can add to it an $O(d, d;\mathbb{Z})$ geometric structure and construct the supergravity theory inspired by double field theory through the use of a suitable commutative star product. The latter implements the weak constraint of the double field theory on its fields and gauge parameters in order to have a closed gauge symmetry algebra. The consistency of the action here proposed is based on the orthogonality of the momenta associated with fields in their triple star products in the cubic terms defined for $d\ge1$. This orthogonality holds also for an arbitrary number of star products of fields for $d=1$. Finally, we extend our analysis to the double sigma model, non-commutative geometry and open string theory.Comment: 27 pages, minor changes, references adde

Photon-assisted Landau-Zener transition: Role of coherent superposition states

We investigate a Landau-Zener (LZ) transition process modeled by a quantum two-level system (TLS) coupled to a photon mode when the bias energy is varied linearly in time. The initial state of the photon field is assumed to be a superposition of coherent states, leading to a more intricate LZ transition. Applying the rotating-wave approximation (RWA), analytical results are obtained revealing the enhancement of the LZ probability by increasing the average photon number. We also consider the creation of entanglement and the change of photon statistics during the LZ process. Without the RWA, we find some qualitative differences of the LZ dynamics from the RWA results, e.g., the average photon number no longer monotonically enhances the LZ probability. The ramifications and implications of these results are explored.Comment: 9 pages, 7 figure

Clinical communication skills and professionalism education are required from the beginning of medical training - a point of view of family physicians

Background: The Brazilian undergraduate medical course is six years long. As in other countries, a medical residency is not obligatory to practice as a doctor. In this context, this paper aims to clarify what and when competencies in communication and professionalism should be addressed, shedding light on the role of university, residency and post-residency programmes. Methods: Brazilian family physicians with diverse levels of medical training answered a questionnaire designed to seek a consensus on the competencies that should be taught (key competencies) and when students should achieve them during their medical training. The data were analysed using descriptive statistics and correlation tests. Results: A total of seventy-four physicians participated; nearly all participants suggested that the students should achieve communication and professionalism competencies during undergraduate study (twenty out of thirty competencies – 66.7%) or during residency (seven out of thirty competencies – 23.33%). When competencies were analysed in domains, the results were that clinical communication skills and professionalism competencies should be achieved during undergraduate medical education, and interpersonal communication and leadership skills should be reached during postgraduate study. Conclusion: The authors propose that attainment of clinical communication skills and professionalism competencies should be required for undergraduate students. The foundation for Leadership and Interpersonal Abilities should be particularly formed at an undergraduate level and, furthermore, mastered by immersion in the future workplace and medical responsibilities in residency.There was no direct financial support for this research. Financial support for the authors is provided by scholarships from the National Counsel of Technological and Scientific Development (CNPq), Brazil (229753/2013–2) and the Coordination for the Improvement of Higher Education Personnel (CAPES), Brazil (13271/13–0)

Spin Squeezing under Non-Markovian Channels by Hierarchy Equation Method

We study spin squeezing under non-Markovian channels, and consider an ensemble of $N$ independent spin-1/2 particles with exchange symmetry. Each spin interacts with its own bath, and the baths are independent and identical. For this kind of open system, the spin squeezing under decoherence can be investigated from the dynamics of the local expectations, and the multi-qubit dynamics can be reduced into the two-qubit one. The reduced dynamics is obtained by the hierarchy equation method, which is a exact without rotating-wave and Born-Markov approximation. The numerical results show that the spin squeezing displays multiple sudden vanishing and revival with lower bath temperature, and it can also vanish asymptotically.Comment: 7 pages, 4 figure

Genome-wide profiling of uncapped mRNA

Gene transcripts are under extensive posttranscriptional regulation, including the regulation of their stability. A major route for mRNA degradation produces uncapped mRNAs, which can be generated by decapping enzymes, endonucleases, and small RNAs. Profiling uncapped mRNA molecules is important for the understanding of the transcriptome, whose composition is determined by a balance between mRNA synthesis and degradation. In this chapter, we describe a method to profile these uncapped mRNAs at the genome scale