Competition between decay and dissociation of core-excited OCS studied by X-ray scattering

We show the first evidence of dissociation during resonant inelastic soft X-ray scattering. Carbon and oxygen K-shell and sulfur L-shell resonant and non-resonant X-ray emission spectra were measured using monochromatic synchrotron radiation for excitation and ionization. After sulfur, L2,3 -> {\pi}*, {\sigma}* excitation, atomic lines are observed in the emission spectra as a consequence of competition between de-excitation and dissociation. In contrast the carbon and oxygen spectra show weaker line shape variations and no atomic lines. The spectra are compared to results from ab initio calculations and the discussion of the dissociation paths is based on calculated potential energy surfaces and atomic transition energies.Comment: 12 pages, 6 pictures, 2 tables, http://link.aps.org/doi/10.1103/PhysRevA.59.428

Radiative processes as a condensation phenomenon and the physical meaning of deformed canonical structures

Working with well known models in $(2+1)D$ we discuss the physics behind the deformation of the canonical structure of these theories. A new deformation is constructed linking the massless scalar field theory with the self-dual theory. This is the exact dual of the known deformation connecting the Maxwell theory with the Maxwell-Chern-Simons theory. Duality is used to establish a web of relations between the mentioned theories and a physical picture of the deformation procedure is suggested.Comment: revtex4 file, 16 page

Out of equilibrium: understanding cosmological evolution to lower-entropy states

Despite the importance of the Second Law of Thermodynamics, it is not absolute. Statistical mechanics implies that, given sufficient time, systems near equilibrium will spontaneously fluctuate into lower-entropy states, locally reversing the thermodynamic arrow of time. We study the time development of such fluctuations, especially the very large fluctuations relevant to cosmology. Under fairly general assumptions, the most likely history of a fluctuation out of equilibrium is simply the CPT conjugate of the most likely way a system relaxes back to equilibrium. We use this idea to elucidate the spacetime structure of various fluctuations in (stable and metastable) de Sitter space and thermal anti-de Sitter space.Comment: 27 pages, 11 figure

Patients’ Perspectives Regarding Digital Health Technology to Support Self-management and Improve Integrated Stroke Care:Qualitative Interview Study

Background: Digital technologies such as mobile apps and robotics have the potential to involve stroke patients better in the care process and to promote self-management. However, barriers exist that constrain the adoption and acceptance of technology in clinical practice. Examples of barriers are privacy concerns, challenges regarding usability, and the perception that there is no need for health-related technology. To address these barriers, co-design can be used to enable patients to reflect on their experiences of a service and to tailor digital technologies to the needs and preferences of end users regarding content and usability. Objective: This study aims to explore the perspectives of stroke patients toward how digital health technology could support self-management regarding health and well-being, as well as integrated stroke care. Methods: A qualitative study was conducted to understand patient perspectives. Data were collected in co-design sessions during the ValueCare study. Patients from a Dutch hospital who experienced an ischemic stroke (n=36) within the past 18 months were invited to participate. Data collection took place between December 2020 and April 2021 via one-to-one telephone interviews. A short self-report questionnaire was used to collect data on sociodemographics, disease-specific information, and technology use. All interviews were audio-taped and transcribed verbatim. The interview data were analyzed using a thematic approach. Results: Patients held mixed attitudes toward digital health technologies. Some patients viewed digital technology as a convenient product or service, while others expressed no desire or need to use technology for self-management or care. Digital features suggested by stroke patients included (1) information about the causes of stroke, medication, prognosis, and follow-up care; (2) an online library with information regarding stroke-related health and care issues; (3) a personal health record by which patients can retrieve and manage their own health information; and (4) online rehabilitation support to empower patients to exercise at home. Regarding the user interface of future digital health technology, patients emphasized the need for easy-to-use and simple designs. Conclusions: Stroke patients mentioned credible health information, an online library with stroke-related health and care information, a personal health record, and online rehabilitation support as the main features to include in future digital health technologies. We recommend that developers and designers of digital health for stroke care listen to the “voice of the stroke patients” regarding both functionality and the characteristics of the interface.</p

SAperI: Approaching Gender Gap Using Spatial Ability Training Week in High-School Context

The purpose of this paper is to describe the structure of a girls summer school, “SAperI – Spatial Ability per l’Ingegneria” (in English, “Knowledge – Spatial Ability for Engineering”), and to illustrate its impact on spatial ability development and future career preferences on those who participated in the week long summer school compared to a control group that did not participate.The 5 days school,organized by Politecnico di Torino (Italy), was included in a larger project addressing 17 years old high-school students. Thirtyseven girls actively took part in a summer school, while 167 students (both males and females) were tested as a controlled group.For those who attended the summer school, significant gains were observed in four measures of spatial ability - mental rotation, spatialvisualization, mental cutting and paper folding. For a minority of participants, scores on one of these tests, paper folding, were lower when measured at the end of the summer school but this was an exception. Furthermore, when tested several months after the summer school, the gains in spatial ability that were made during the course were maintained indicating stability over time with regard to the improvement in spatial ability.In terms of the experience of taking the course, the feedback provided was very positive and all but one participant would recommend the summer school to othergirls at this stage of high school

Testing spatial noncommutativiy via the Aharonov-Bohm effect

The possibility of detecting noncommutative space relics is analyzed using the Aharonov-Bohm effect. We show that, if space is noncommutative, the holonomy receives non-trivial kinematical corrections that will produce a diffraction pattern even when the magnetic flux is quantized. The scattering problem is also formulated, and the differential cross section is calculated. Our results can be extrapolated to high energy physics and the bound $\theta \sim [ 10 {TeV}]^{-2}$ is found. If this bound holds, then noncommutative effects could be explored in scattering experiments measuring differential cross sections for small angles. The bound state Aharonov- Bohm effect is also discussed.Comment: 16 pp, Revtex 4, 2 fig, new references added. To appear in PR

Lorentz-violating Chern-Simons action under high temperature in massless QED

Lorentz and CPT violating QED with massless fermions at finite temperature is studied. We show that there is no ambiguity in the induced coefficient of the Chern-Simons-like term that defines the so-called Carroll-Field-Jackiw model at high temperature. We also show that this system constitutes an example where the breaking of CPT and Lorentz symmetries is more severe at high temperature than in the zero temperature case thus precluding any naive expectations of Lorentz symmetry restoration.Comment: 6 pages, 1 figure, final version to appear in Phys. Lett.

Dilepton production from p-p to Ca-Ca at the Bevalac

The DLS collaboration has recently completed a high statistics study of dilepton production at the Bevalac. In particular, we have measured dielectrons (e+e-) from p-p and p-d collisions to understand the basic dilepton production mechanisms in the energy range from 1.05 - 4.9 GeV. These data can be used to determine the basic processes which contribute to nucleon-nucleon dilepton production such as hadronic bremsstrahlung, vector meson processes, and hadronic Dalitz decay. The data show that a simple elastic bremsstrahlung calculation is insufficient to explain the data. Theoretical models are compared with the data. A new high statistics study of Ca-Ca at 1.05 A GeV has been made to study the collectivity of A-A collisions

The Role of Color Neutrality in Nuclear Physics--Modifications of Nucleonic Wave Functions

The influence of the nuclear medium upon the internal structure of a composite nucleon is examined. The interaction with the medium is assumed to depend on the relative distances between the quarks in the nucleon consistent with the notion of color neutrality, and to be proportional to the nucleon density. In the resulting description the nucleon in matter is a superposition of the ground state (free nucleon) and radial excitations. The effects of the nuclear medium on the electromagnetic and weak nucleon form factors, and the nucleon structure function are computed using a light-front constituent quark model. Further experimental consequences are examined by considering the electromagnetic nuclear response functions. The effects of color neutrality supply small but significant corrections to predictions of observables.Comment: 37 pages, postscript figures available on request to [email protected]