On the problem of interactions in quantum theory

The structure of representations describing systems of free particles in the theory with the invariance group SO(1,4) is investigated. The property of the particles to be free means as usual that the representation describing a many-particle system is the tensor product of the corresponding single-particle representations (i.e. no interaction is introduced). It is shown that the mass operator contains only continuous spectrum in the interval $(-\infty,\infty)$ and such representations are unitarily equivalent to ones describing interactions (gravitational, electromagnetic etc.). This means that there are no bound states in the theory and the Hilbert space of the many-particle system contains a subspace of states with the following property: the action of free representation operators on these states is manifested in the form of different interactions. Possible consequences of the results are discussed.Comment: 35 pages, Late

Trauma management incorporating focused assessment with computed tomography in trauma (FACTT) - potential effect on survival

Background Immediate recognition of life-threatening conditions and injuries is the key to trauma management. To date, the impact of focused assessment with computed tomography in trauma (FACTT) has not been formally assessed. We aimed to find out whether the concept of using FACTT during primary trauma survey has a negative or positive effect on survival. Methods In a retrospective, multicentre study, we compared our time management and probability of survival (Ps) in major trauma patients who received FACTT during trauma resuscitation with the trauma registry of the German Trauma Society (DGU). FACTT is defined as whole-body computed tomography (WBCT) during primary trauma survey. We determined the probability of survival according to the Trauma and Injury Severity Score (TRISS), the Revised Injury Severity Classification score (RISC) and the standardized mortality ratio (SMR). Results We analysed 4.817 patients from the DGU database from 2002 until 2004, 160 (3.3%) were from our trauma centre at the Ludwig-Maximilians-University (LMU) and 4.657 (96.7%) from the DGU group. 73.2% were male with a mean age of 42.5 years, a mean ISS of 29.8. 96.2% had suffered from blunt trauma. Time from admission to FAST (focused assessment with sonography for trauma)(4.3 vs. 8.7 min), chest x-ray (8.1 vs. 16.0 min) and whole-body CT (20.7 vs. 36.6 min) was shorter at the LMU compared to the other trauma centres (p < 0.001). SMR calculated by TRISS was 0.74 (CI95% 0.40-1.08) for the LMU (p = 0.24) and 0.92 (CI95% 0.84-1.01) for the DGU group (p = 0.10). RISC methodology revealed a SMR of 0.69 (95%CI 0.47-0.92) for the LMU (p = 0.043) and 1.00 (95%CI 0.94-1.06) for the DGU group (p = 0.88). Conclusion Trauma management incorporating FACTT enhances a rapid response to life-threatening problems and enables a comprehensive assessment of the severity of each relevant injury. Due to its speed and accuracy, FACTT during primary trauma survey supports rapid decision-making and may increase survival

Child and family experiences with inborn errors of metabolism: a qualitative interview study with representatives of patient groups

© 2015, The Author(s). Background: Patient-centered health care for children with inborn errors of metabolism (IEM) and their families is important and requires an understanding of patient experiences, needs, and priorities. IEM-specific patient groups have emerged as important voices within these rare disease communities and are uniquely positioned to contribute to this understanding. We conducted qualitative interviews with IEM patient group representatives to increase understanding of patient and family experiences, needs, and priorities and inform patient-centered research and care. Methods: We developed a sampling frame of patient groups representing IEM disease communities from Canada, the United States, and United Kingdom. With consent, we interviewed participants to explore their views on experiences, needs, and outcomes that are most important to children with IEM and their families. We analyzed the data using a qualitative descriptive approach to identify key themes and sub-themes. Results: We interviewed 18 organizational representatives between February 28 and September 17, 2014, representing 16 IEMs and/or disease categories. Twelve participants voluntarily self-identified as parents and/or were themselves patients. Three key themes emerged from the coded data: managing the uncertainty associated with raising and caring for a child with a rare disease; challenges associated with the affected child’s life transitions, and; the collective struggle for improved outcomes and interventions that rare disease communities navigate. Conclusion: Health care providers can support children with IEM and their families by acknowledging and reducing uncertainty, supporting families through children’s life transitions, and contributing to rare disease communities’ progress toward improved interventions, experiences, and outcomes.The study was partially funded by the Rare Disease Foundation (RDF). In-kind support was provided by the Canadian Inherited Metabolic Diseases Research Network (CIMDRN) which is funded by the Canadian Institutes of Health Research (CIHR, grant TR3-119197) and administered by the University of Ottawa

On the commutant of an irreducible set of operators in real Hilbert space

SIGLECopy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman