Coarse Grained Liouville Dynamics of piecewise linear discontinuous maps

We compute the spectrum of the classical and quantum mechanical coarse-grained propagators for a piecewise linear discontinuous map. We analyze the quantum - classical correspondence and the evolution of the spectrum with increasing resolution. Our results are compared to the ones obtained for a mixed system.Comment: 11 pages, 8 figure

Classical to quantum correspondence in dissipative directed transport

We compare the quantum and classical properties of the (Quantum) Isoperiodic Stable Structures -- (Q)ISSs -- which organize the parameter space of a paradigmatic dissipative ratchet model, i.e. the dissipative modified kicked rotator. We study the spectral behavior of the corresponding classical Perron-Frobenius operators with thermal noise and the quantum superoperators without it for small $\hbar_{\rm eff}$ values. We find a remarkable similarity between the classical and quantum spectra. This finding significantly extends previous results -- obtained for the mean currents and asymptotic distributions only -- and on the other hand unveils a classical to quantum correspondence mechanism where the classical noise is qualitatively different from the quantum one. This is crucial not only for simple attractors but also for chaotic ones, where just analyzing the asymptotic distribution reveals insufficient. Moreover, we provide with a detailed characterization of relevant eigenvectors by means of the corresponding Weyl-Wigner distributions, in order to better identify similarities and differences. Finally, this model being generic, it allows us to conjecture that this classical to quantum correspondence mechanism is a universal feature of dissipative systems.Comment: 7 pages, 6 figure

Violet is one letter off from violent

The poems in this creative collection, Violet is one letter off from violent, aim to add to the critical conversation in contemporary poetry about violence, women’s anger, patriarchal oppression, and physical and sexual assault, specifically drawing on analyses from the poetry of Rachel McKibbens, Tarfia Faizullah, Emily Skaja, Erika L. Sánchez, Tracy K. Smith, Safiya Sinclair, and Paisley Rekdal. My myriad speakers, who take both first and third person points of narrative view, reclaim and reproduce their own stories in ways that are complex, vulnerable, and angry as a result of living under and through traumatic experiences in domestic and public spheres. However, this reclamation of power written in poetic verse from marginalized people and survivors is not a new realization or discovery in contemporary poetry and literary studies, as the poets above have demonstrated in their works. Extending this discourse, my collection adds to the conservation by positioning the international museum—whose history I show is inherently violent—aiming to present how it is another vehicle, and historically White institution, through which aggression and violence shape and control female and BIPOC bodies, particularly women who have been pushed to the margins. As Gaby Porter posits in her essay, “Seeing through Solidarity: a feminist perspective on museums,” the sheer act of classification and categorization stemming from the masculine tradition of rationale and order derivative of the Enlightenment era allows us to turn to a critical, feminist lens in museum display and collections to show how “these practices appear to construct and maintain the male order with woman at its margins” (112). The opening poem of my collection, “Self-Portrait as the Museum,” then demonstrates the speaker’s positionality as a metaphorical embodiment of the museum and its practice. Her 2 reclaiming comes in her ability to reproduce traumatic memories, “to circle / the shapes slowly like rosaries, mother [her] violet / body gone to bone.” In the end, both she and the museum are the result of “violent making,” but power resides in her ability to assert control over her memories and history. Acceptance lies in the unknown and the known, the ability to speak through years of silencing. This poem introduces the reader to the mirroring and blending of spaces and bodies, which cements this collection. To emphasis this connection, I have broken the book into three, main sections, or “Galleries” to structure the book as if one is walking through a museum’s exhibits

Mandatory vaccinations in European countries, undocumented information, false news and the impact on vaccination uptake: the position of the Italian pediatric society.

BACKGROUND: High rates of vaccination coverage are important in preventing infectious diseases. Enforcing mandatory vaccinations is one of the strategies that some Countries adopted to protect the community when vaccination coverage is not satisfactory. In Italy, in 2017 vaccination against diphtheria, tetanus, pertussis, hepatitis B, poliovirus, Haemophilus influenzae type b, measles, mumps, rubella and varicella became compulsory in childhood. In order to contrast vaccination policies, anti-vaccination campaigns contribute to the spread of fake news. Among them, there is the false information that Italy is the only one country with mandatory vaccination policy. Aim of our study is confronting vaccination policies in children under 18 months against among different European countries for the following vaccines: diphtheria, tetanus, pertussis, hepatitis B, poliovirus, Haemophilus influenzae type b, measles, mumps, rubella and varicella. METHODS: Information on policies of mandatory or recommended vaccinations of the European Countries were gathered by ECDC and compared to the Italian one. RESULTS: European Countries recommend or contemplate compulsory vaccines. Among them, eleven Countries (35.4%) have mandatory vaccinations for at least one out of diphtheria, tetanus, pertussis, hepatitis B, poliovirus, Haemophilus influenzae type b, measles, mumps, rubella and varicella vaccine. CONCLUSION: Not only in Italy, vaccination against diphtheria, tetanus, pertussis, hepatitis B, poliovirus, Haemophilus influenzae type b, measles, mumps, rubella and varicella is mandatory in children under 18 months. Other European countries adopted compulsory policies in order to prevent the spread of infectious diseases and to protect the community

Thermal effects on chaotic directed transport

We study a chaotic ratchet system under the influence of a thermal environment. By direct integration of the Lindblad equation we are able to analyze its behavior for a wide range of couplings with the environment, and for different finite temperatures. We observe that the enhancement of the classical and quantum currents due to temperature depend strongly on the specific properties of the system. This makes difficult to extract universal behaviors. We have also found that there is an analogy between the effects of the classical thermal noise and those of the finite $\hbar$ size. These results open many possibilities for their testing and implementation in kicked BECs and cold atoms experiments.Comment: 5 pages, 4 figure

Weyl law for fat fractals

It has been conjectured that for a class of piecewise linear maps the closure of the set of images of the discontinuity has the structure of a fat fractal, that is, a fractal with positive measure. An example of such maps is the sawtooth map in the elliptic regime. In this work we analyze this problem quantum mechanically in the semiclassical regime. We find that the fraction of states localized on the unstable set satisfies a modified fractal Weyl law, where the exponent is given by the exterior dimension of the fat fractal.Comment: 8 pages, 4 figures, IOP forma

Quantum Spectra of Triangular Billiards on the Sphere

We study the quantal energy spectrum of triangular billiards on a spherical surface. Group theory yields analytical results for tiling billiards while the generic case is treated numerically. We find that the statistical properties of the spectra do not follow the standard random matrix results and their peculiar behaviour can be related to the corresponding classical phase space structure.Comment: 18 pages, 5 eps figure

Risk Perception and Coping Strategies among Direct Support Professionals in the Age of COVID-19.

The spread of novel coronavirus (COVID-19) across the globe and its associated morbidity and mortality has impacted and challenged society in many ways, which resulted in adapting to a new way of life. One underrecognized and unaddressed area is the mental health of essential employees providing services to people with intellectual and developmental disabilities (IDD). Direct support professionals (DSPs) serve an important function in the daily supervision and care of clients with IDD. It is not clear, however, how these essential workers perceived their own risk of contracting COVID-19 while working during this pandemic. Our research presents results of a national survey of 478 DSPs that focused on perceptions of risk and ways of coping with COVID-19. Using an online survey, we examined DSPs’ perception of risk and on the emotional and problem-solving strategies they used to cope with the global crisis. We found that DSPs engaged in higher problem-focused strategies rather than emotion-focused strategies in coping with the virus. As such, we show that it is critical for IDD provider organizations to assess DSPs’ needs to provide coping supports during the age of COVID