Physical interpretation of the Wigner rotations and its implications for relativistic quantum information

We present a new treatment for the spin of a massive relativistic particle in the context of quantum information based on a physical interpretation of the Wigner rotations, obtaining different results in relation to the previous works. We are lead to the conclusions that it is not possible to define a reduced density matrix for the particle spin and that the Pauli-Lubanski (or similar) spin operators are not suitable to describe measurements where spin couples to an electromagnetic field in the measuring apparatus. These conclusions contradict the assumptions made by most of the previous papers on the subject. We also propose an experimental test of our formulation.Comment: 10 pages, 2 figures. Several changes were made on the text. One extra example was include

Ultrasound Guidance Superiority in Pediatric Sialorrhea Treatment With Intraglandular Botulinum Toxin Application: A Four-Year Retrospective Study

Introduction The management of sialorrhea in children with multiple disabilities is extremely important not only for aesthetic/psychosocial reasons but also for functional and clinical ones. There are several recommended management methods with strong evidence of the effectiveness of intraglandular application of botulinum toxin A. Materials and methods In this four-year retrospective report, we compare two populations who received intraglandular type A botulinum toxin injections in the pediatric unit of the Physical Medicine and Rehabilitation (PM&R) Department at a central hospital. The injections were administered using either ultrasound guidance (US) or anatomical landmarks. Results Out of a total of 29 patients with neurological conditions, 16 met the eligibility criteria for this study. The study group comprised seven females (44%) and nine males (56%), with a median age of 9 years. The average pre-procedure sialorrhea staging was four. A total of 23 procedures were performed, with 16 conducted under ultrasound guidance (US) and seven via anatomical landmarks (non-US). In the US group, a statistically significant difference in sialorrhea staging was observed at one and three months post-procedure (p<0.05), but not at six months post-procedure. Conversely, no statistically significant difference in sialorrhea staging was found at any time point in the non-US group. The comparison between the two groups supports the use of ultrasound guidance, showing superior outcomes at one and three months post-procedure (p<0.05). Conclusion The results of this study align with global trends seen in medical publications and guidelines advocating for the use of ultrasound in this procedure. Future prospective and larger-scale studies are essential to validate these findings.info:eu-repo/semantics/publishedVersio

Energy and momentum entanglement in parametric downconversion

We present a simple treatment for the phenomenon of parametric downconversion considering the coherent scattering of one pump photon into a photon pair by a nonlinear crystal. The energy and momentum entanglement of the quantum state of the generated twin photons are seen as a consequence of the fundamental indistinguishability of the time and the position in which the photon pair is created inside the crystal. We also discuss some consequences of the system entanglement.Comment: 6 pages, 2 figures. v3: Minor changes on the text. Some references were include

Effect of Progressive Muscle Relaxation in Female Health Care Professionals

Background: Increasing population, fast paced industrialization, increased, competitiveness, unanticipated problems in the work place have increased the stress among the females working in health care in recent times.Aim: The aim of the following study is to detect the stress levels among female health care professionals in the age group of 25-35 years and its impact on health. Subjects and Methods: A prospective cross-sectional pilot project was conducted in a tertiary care hospital in Eastern part of India, after receiving approval from the Institutional Ethics Committee and informed consent form was taken from the subjects. Stress level in the subjects was  assessed according to the presumptive life event stress scale. Females withscores above 200 were selected. For these, initial assessment of  anthropometric measurement, electrocardiogram and lipid profile analysis, resting pulse rate, blood pressure, physical fitness index (PFI), breath holding time (BHT), isometric hand grip (IHG) test results were evaluatedand recorded. All subjects were given training of progressive muscle  relaxation (PMR) for 3 months. After 3 months, the lipid profile and vital parameters, Perceived Stress Scale values were re-evaluated and subjects were asked to repeat the same exercises and data thus recorded were analyzed using Statistical Package for the Social Sciences (SPSS) version 16 (SPSS Inc. Released 2007. SPSS for Windows, Version 16.0. Chicago, SPSS Inc.).Results: Significant decrease in resting heart rate, blood pressure and Perceived Stress Scale levels was seen after PMR training in the subjects. Results of BHT, IHG tests and PFI were significantly increased after PMR training. There was a significant decrease in total cholesterol, triglyceride and low-density lipoprotein cholesterol in subjects after practicing PMR for 3 months. Conclusions: Increasing stress among female health care professionals is a cause for concern and there is a need to adopt early life-style  modification by practicing relaxation exercises to ameliorate stress and to improve not only their quality-of-life in general, but patient care in  particular.Keywords: Female stress, relaxation techniques, health care professional