Quantum mechanics and elements of reality inferred from joint measurements

The Einstein-Podolsky-Rosen argument on quantum mechanics incompleteness is formulated in terms of elements of reality inferred from joint (as opposed to alternative) measurements, in two examples involving entangled states of three spin-1/2 particles. The same states allow us to obtain proofs of the incompatibility between quantum mechanics and elements of reality.Comment: LaTeX, 12 page

Quantitative system drift compensates for altered maternal inputs to the gap gene network of the scuttle fly Megaselia abdita.

Published onlineJournal ArticleThis is the final version of the article. Available from eLife Sciences Publications via the DOI in this record.The segmentation gene network in insects can produce equivalent phenotypic outputs despite differences in upstream regulatory inputs between species. We investigate the mechanistic basis of this phenomenon through a systems-level analysis of the gap gene network in the scuttle fly Megaselia abdita (Phoridae). It combines quantification of gene expression at high spatio-temporal resolution with systematic knock-downs by RNA interference (RNAi). Initiation and dynamics of gap gene expression differ markedly between M. abdita and Drosophila melanogaster, while the output of the system converges to equivalent patterns at the end of the blastoderm stage. Although the qualitative structure of the gap gene network is conserved, there are differences in the strength of regulatory interactions between species. We term such network rewiring 'quantitative system drift'. It provides a mechanistic explanation for the developmental hourglass model in the dipteran lineage. Quantitative system drift is likely to be a widespread mechanism for developmental evolution.Ministerio de Economía y Competitividad MEC/EMBL Agreement/ BFU2009-10184/ BFU2012-33775/ SEV-2012-0208 Agència de Gestió d'Ajuts Universitaris I de Recerca SGR Grant 406 European Commission FP7-KBBE-2011-5/289434 National Science Foundation IOS-0719445/IOS-112121

Proposed experimental tests of the Bell-Kochen-Specker theorem

For a two-particle two-state system, sets of compatible propositions exist for which quantum mechanics and noncontextual hidden-variable theories make conflicting predictions for every individual system whatever its quantum state. This permits a simple all-or-nothing state-independent experimental verification of the Bell-Kochen-Specker theorem.Comment: LaTeX, 8 page

Atrial fibrosis identification with unipolar electrogram eigenvalue distribution analysis in multi-electrode arrays

Atrial fbrosis plays a key role in the initiation and progression of atrial fbrillation (AF). Atrial fbrosis is typically identifed by a peak-to-peak amplitude of bipolar electrograms (b-EGMs) lower than 0.5 mV, which may be considered as ablation targets. Nevertheless, this approach disregards signal spatiotemporal information and b-EGM sensitivity to catheter orientation. To overcome these limitations, we propose the dominant-to-remaining eigenvalue dominance ratio (EIGDR) of unipolar electrograms (u-EGMs) within neighbor electrode cliques as a waveform dispersion measure, hypothesizing that it is correlated with the presence of fbrosis. A simulated 2D tissue with a fbrosis patch was used for validation. We computed EIGDR maps from both original and time-aligned u-EGMs, denoted as R and RA, respectively, also mapping the gain in eigenvalue concentration obtained by the alignment, ΔRA. The performance of each map in detecting fbrosis was evaluated in scenarios including noise and variable electrode-tissue distance. Best results were achieved by RA, reaching 94% detection accuracy, versus the 86% of b-EGMs voltage maps. The proposed strategy was also tested in real u-EGMs from fbrotic and non-fbrotic areas over 3D electroanatomical maps, supporting the ability of the EIGDRs as fbrosis markers, encouraging further studies to confrm their translation to clinical settings

XXVI Congreso Nacional y II Congreso Internacional de SEDEM

Organizan: Sociedad Española de Educación Médica y Facultad de Medicina y Enfermería, Universidad del País Vasco (UPV/EHU)Comunicaciones aceptadas en el XXVI Congreso de la Sociedad Española de Educación Médica, celebrado en Bilbao del 28 al 30 de noviembre de 2024

Radiation reaction on a classical charged particle: a modified form of the equation of motion

We present and numerically solve a modified form of the equation of motion for a charged particle under the influence of an external force, taking into account the radiation reaction. This covariant equation is integro differential, as Dirac-Rohrlich's, but has several technical improvements. First, the equation has the form of Newton's second law, with acceleration isolated on the left hand side and the force depending only on positions and velocities: Thus, the equation is linear in the highest derivative. Second, the total four-force is by construction perpendicular to the four-velocity. Third, if the external force vanishes for all future times, the total force and the acceleration automatically vanish at the present time. We show the advantages of this equation by solving it numerically for several examples of external force