The Measurement Process in Local Quantum Theory and the EPR Paradox

We describe in a qualitative way a possible picture of the Measurement Process in Quantum Mechanics, which takes into account: 1. the finite and non zero time duration T of the interaction between the observed system and the microscopic part of the measurement apparatus; 2. the finite space size R of that apparatus; 3. the fact that the macroscopic part of the measurement apparatus, having the role of amplifying the effect of that interaction to a macroscopic scale, is composed by a very large but finite number N of particles. The conventional picture of the measurement, as an instantaneous action turning a pure state into a mixture, arises only in the limit in which N and R tend to infinity, and T tends to 0. We sketch here a proposed scheme, which still ought to be made mathematically precise in order to analyse its implications and to test it in specific models, where we argue that in Quantum Field Theory this picture should apply to the unique time evolution expressing the dynamics of a given theory, and should comply with the Principle of Locality. We comment on the Einstein Podolski Rosen thought experiment (partly modifying the discussion on this point in an earlier version of this note), reformulated here only in terms of local observables (rather than global ones, as one particle or polarisation observables). The local picture of the measurement process helps to make it clear that there is no conflict with the Principle of Locality.Comment: 18 page

A first experimental test of de Broglie-Bohm theory against standard quantum mechanics

De Broglie - Bohm (dBB) theory is a deterministic theory, built for reproducing almost all Quantum Mechanics (QM) predictions, where position plays the role of a hidden variable. It was recently shown that different coincidence patterns are predicted by QM and dBB when a double slit experiment is realised under specific conditions and, therefore, an experiment can test the two theories. In this letter we present the first realisation of such a double slit experiment by using correlated photons produced in type I Parametric Down Conversion. Our results confirm QM contradicting dBB predictions

A Pediatric Infectious Disease Perspective of SARS-CoV-2 and COVID-19 in Children.

Understanding the role that children play in the clinical burden and propagation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) responsible for novel coronavirus (COVID-19) infections is emerging. While the severe manifestations and acute clinical burden of COVID-19 has largely spared children compared to adults, understanding the epidemiology, clinical presentation, diagnostics, management, and prevention opportunities as well as the social and behavioral impacts on child health is vital. Foremost is clarifying the contribution of asymptomatic and mild infections to transmission within the household and community and the clinical and epidemiologic significance of uncommon severe post-infectious complications. Herein we summarize the current knowledge, identify useful resources, and outline research opportunities. Pediatric infectious disease clinicians have a unique opportunity to advocate for the inclusion of children in epidemiological, clinical, treatment and prevention studies to optimize their care, as well as to represent children in the development of guidance and policy during pandemic response

Copy number alterations in pancreatic cancer identify recurrent PAK4 amplification

Pancreatic cancer is one of the most lethal of all cancers. The median survival is 6 months, and less than 5% of those diagnosed survive 5-years. Recurrent genetic deletions and amplifications in 73 pancreatic adenocarcinomas, the largest sample set analyzed to date for pancreatic cancer, were defined using comparative genomic hybridization The recurrent genetic alterations identified target a number of previously well-characterized genes, as well as regions that contain possible new oncogenes and tumor suppressor genes. We have focused on chromosome 19q13, a region frequently found amplified in pancreatic cancer, and demonstrate how boundaries of common regions of mutation can be mapped, and how a gene, in this case PAK4 amplified on chromosome19q13, can be functionally validated. We show that although the PAK4 gene is not activated by mutation in cell lines with gene amplification, an oncogenic form of the KRAS2 gene is present in these cells, and oncogenic KRAS2 can activate PAK4. In fact in the three samples we identified with PAK4 gene amplification, the KRAS2 gene was activated and genomically amplified. The kinase activity of the PAK4 protein is significantly higher in cells with genomic amplification as compared to cells without amplification. Our study demonstrates the utility of analyzing copy number data in a large set of neoplasms to identify genes involved in cancer. We have generated a useful dataset which will be particularly useful for the pancreatic cancer community as efforts are undertaken to sequence the pancreatic cancer genome

Multicentre evaluation of the Naída Ci Q70 sound processor: Feedback from cochlear implant users and professionals

The aim of this survey was to gather data from both implant recipients and professionals on the ease of use of the Naída CI Q70 (Naída CI) sound processor from Advanced Bionics and on the usefulness of the new functions and features available. A secondary objective was to investigate fitting practices with the new processor. A comprehensive user satisfaction survey was conducted in a total of 186 subjects from 24 centres. In parallel, 23 professional questionnaires were collected from 11 centres. Overall, there was high satisfaction with the Naída CI processor from adults, children, experienced and new CI users as well as from professionals. The Naída CI processor was shown as being easy to use by all ages of recipients and by professionals. The majority of experienced CI users rated the Naída CI processor as being similar or better than their previous processor in all areas surveyed. The Naída CI was recommended by the professionals for fitting in all populations. Features like UltraZoom, ZoomControl and DuoPhone would not be fitted to very young children in contrast to adults. Positive ratings were obtained for ease of use, comfort and usefulness of the new functions and features of the Naída CI sound processor. Seventy-seven percent of the experienced CI users rated the new processor as being better than their previous sound processor from a general point of view. The survey also showed that fitting practices were influenced by the age of the user

Related and unrelated donor transplantation for β-thalassemia major: results of an international survey.

We studied 1110 patients with β-thalassemia major aged ≤25 years who received transplants with grafts from HLA-matched related (n = 677; 61%), HLA-mismatched related (n = 78; 7%), HLA-matched unrelated (n = 252; 23%), and HLA-mismatched unrelated (n = 103; 9%) donors between 2000 and 2016. Ninety percent of transplants were performed in the last decade. Eight-five percent of patients received ≥20 transfusions and 88% were inadequately chelated. All patients received myeloablative-conditioning regimen. Overall and event-free survival were highest for patients aged ≤6 years and after HLA-matched related and HLA-matched unrelated donor transplantation. The 5-year probabilities of overall survival for patients aged ≤6 years, 7 to 15 years, and 16 to 25 years, adjusted for donor type and conditioning regimen were 90%, 84%, and 63%, respectively (P < .001). The corresponding probabilities for event-free survival were 86%, 80%, and 63% (P < .001). Overall and event-free survival did not differ between HLA-matched related and HLA-matched unrelated donor transplantation (89% vs 87% and 86% vs 82%, respectively). Corresponding probabilities after mismatched related and mismatched unrelated donor transplantation were 73% vs 83% and 70% vs 78%. In conclusion, if transplantation is considered as a treatment option it should be offered early (age ≤6 years). An HLA-matched unrelated donor is a suitable alternative if an HLA-matched relative is not available

Decoherence, the measurement problem, and interpretations of quantum mechanics

Environment-induced decoherence and superselection have been a subject of intensive research over the past two decades, yet their implications for the foundational problems of quantum mechanics, most notably the quantum measurement problem, have remained a matter of great controversy. This paper is intended to clarify key features of the decoherence program, including its more recent results, and to investigate their application and consequences in the context of the main interpretive approaches of quantum mechanics.Comment: 41 pages. Final published versio