Computing reconstructions from nonuniform Fourier samples: Universality of stability barriers and stable sampling rates

We study the problem of recovering an unknown compactly-supported multivariate function from samples of its Fourier transform that are acquired nonuniformly, i.e. not necessarily on a uniform Cartesian grid. Reconstruction problems of this kind arise in various imaging applications, where Fourier samples are taken along radial lines or spirals for example.Specifically, we consider finite-dimensional reconstructions, where a limited number of samples is available, and investigate the rate of convergence of such approximate solutions and their numerical stability. We show that the proportion of Fourier samples that allow for stable approximations of a given numerical accuracy is independent of the specific sampling geometry and is therefore universal for different sampling scenarios. This allows us to relate both sufficient and necessary conditions for different sampling setups and to exploit several results that were previously available only for very specific sampling geometries.The results are obtained by developing: (i) a transference argument for different measures of the concentration of the Fourier transform and Fourier samples; (ii) frame bounds valid up to the critical sampling density, which depend explicitly on the sampling set and the spectrum.As an application, we identify sufficient and necessary conditions for stable and accurate reconstruction of algebraic polynomials or wavelet coefficients from nonuniform Fourier data

Sedimentology, Provenance and Radiometric Dating of the Silante Formation: Implications for the Cenozoic Evolution of the Western Andes of Ecuador

The Silante Formation is a thick series of continental deposits, exposed along a trench-parallel distance of approximately 300 km within the Western Cordillera of Ecuador. The origin, tectonic setting, age and stratigraphic relationships are poorly known, although these are key to understand the Cenozoic evolution of the Ecuadorian Andes. We present new sedimentological, stratigraphic, petrographic, radiometric and provenance data from the Silante Formation and underlying rocks. The detailed stratigraphic analysis shows that the Silante Formation unconformably overlies Paleocene submarine fan deposits of the Pilalo Formation, which was coeval with submarine tholeiitic volcanism. The lithofacies of the Silante Formation suggest that the sediments were deposited in a debris flow dominated alluvial fan. Provenance analysis including heavy mineral assemblages and detrital zircon U-Pb ages indicate that sediments of the Silante Formation were derived from the erosion of a continental, calc-alkaline volcanic arc, pointing to the Oligocene to Miocene San Juan de Lachas volcanic arc. Thermochronological data and regional correlations suggest that deposition of the Silante Formation was coeval with regional rock and surface uplift of the Andean margin that deposited alluvial fans in intermontane and back-arc domains

The phase difference between neural drives to antagonist muscles in essential tremor is associated with the relative strength of supraspinal and afferent input

The pathophysiology of essential tremor (ET), the most common movement disorder, is not fully understood. We investigated which factors determine the variability in the phase difference between neural drives to antagonist muscles, a long-standing observation yet unexplained. We used a computational model to simulate the effects of different levels of voluntary and tremulous synaptic input to antagonistic motoneuron pools on the tremor. We compared these simulations to data from 11 human ET patients. In both analyses, the neural drive to muscle was represented as the pooled spike trains of several motor units, which provides an accurate representation of the common synaptic input to motoneurons. The simulations showed that, for each voluntary input level, the phase difference between neural drives to antagonist muscles is determined by the relative strength of the supraspinal tremor input to the motoneuron pools. In addition, when the supraspinal tremor input to one muscle was weak or absent, Ia afferents provided significant common tremor input due to passive stretch. The simulations predicted that without a voluntary drive (rest tremor) the neural drives would be more likely in phase, while a concurrent voluntary input (postural tremor) would lead more frequently to an out-of-phase pattern. The experimental results matched these predictions, showing a significant change in phase difference between postural and rest tremor. They also indicated that the common tremor input is always shared by the antagonistic motoneuron pools, in agreement with the simulations. Our results highlight that the interplay between supraspinal input and spinal afferents is relevant for tremor generation

Estudio del efecto solvatocrómico en derivados fenólicos naturales

Se describen las características espectrofluorimétricas de dos derivados de quercetina aislados de las hojas deFlaveria bidentis, un derivado de 6-prenilpinocembrina, aislado de las raíces de Dalea elegans y un compuesto deestructura antraquinónica aislado de las hojas de Heterophyllaea pustulata. Todos ellos presentan espectros deabsorción con máximos en la región UV-visible acordes con los grupos cromóforos presentes en su estructura. Loscuatro compuestos estudiados presentan fluorescencia nativa. La posición de los máximos de emisión de fluorescenciase modifica en función del disolvente. Los desplazamientos producidos están relacionados con el diferente gradode solvatación de las moléculas en estado excitado según la polaridad del disolvente. La adición de ácidos mineralesprovoca desplazamientos en los máximos de fluorescencia concordantes con los ya descritos para compuestos deestructura similar. Estas modificaciones espectrales tienen un gran interés analítico desde el punto de vista de laidentificación y caracterización de productos naturales de estructura fenólica

Modelization of anaerobic processes during co-digestion of slowly biodegradable substrates

The influence of the soluble substrates over the anaerobic processes has been extensively investigated, but little is known about the effects of particulate substrate. The biodegradation of these substrates starts with the hydrolytic step, this process is slower than the other ones involved in the biodegradation of particulate substrates and usually becomes the rate-limiting step. This study investigate the effect of the initial total solids (TS) concentration on the anaerobic co-digestion of two slowly biodegradable organic substrates. The wastes mixtures were prepared at different dilutions in the range from 10% to 28% TS. From these experiments it was observed that as TS concentration increased, the methane production decreased. These results were modelled and it was observed that neither hydrolysis nor fermentation stages controlled the methane production rate. Being a substrate inhibition event experienced at the methanogenic stage the responsible of the lower methane production when operating at high TS concentrations.La influencia de los sustratos solubles sobre los procesos anaeróbicos se ha investigado extensamente, pero se sabe poco acerca de los efectos del sustrato particulado. La biodegradación de estos sustratos comienza con el paso hidrolítico, este proceso es más lento que los otros involucrados en la biodegradación de sustratos particulados y generalmente se convierte en el paso limitante de la velocidad. Este estudio investiga el efecto de la concentración inicial de sólidos totales (TS) sobre la codigestión anaeróbica de dos sustratos orgánicos lentamente biodegradables. Las mezclas de desechos se prepararon a diferentes diluciones en el rango de 10% a 28% de TS. A partir de estos experimentos, se observó que a medida que aumentaba la concentración de TS, la producción de metano disminuía. Estos resultados se modelaron y se observó que ni las etapas de hidrólisis ni de fermentación controlaban la tasa de producción de metano. Siendo un evento de inhibición del sustrato experimentado en la etapa metanogénica el responsable de la menor producción de metano cuando se opera a altas concentraciones de TS

Cost-utility model of brivaracetam in the adjunctive treatment of patients with epilepsy in Spain

[EN] Objective This study aims to assess the cost utility of Brivaracetam compared with the third-generation anti-epileptic drugs used as standard care. Methods A cost utility analysis of Brivaracetam was carried out with other third-generation comparators. The treatment pathway of a hypothetical cohort over a period of 2 years was simulated using the Markov model. Data for effectiveness and the QALYs of each health status for epilepsy, as well as for the disutilities of adverse events of treatments, were analyzed through a studies review. The cost of the anti-epileptics and the use of medical resources linked to the different health statuses were taken into consideration. A probabilistic sensitivity analysis was performed using a Monte Carlo simulation. Results Brivaracetam was shown to be the dominant alternative, with Incremental Cost Utility Ratio (ICUR) values from -11,318 for Lacosamide to -128,482 for Zonisamide. The probabilistic sensitivity analysis validates these results. The ICUR sensitivity is greater for increases in the price of Brivaracetam than for decreases, and for Eslicarbizapine over the other adjunctives considered in the analysis. Conclusions Treatment with Brivaracetam resulted in cost effective and incremental quality adjusted life years come at an acceptable cost.Barrachina Martínez, I.; Vivas-Consuelo, D.; Reyes-Santias, F. (2020). Cost-utility model of brivaracetam in the adjunctive treatment of patients with epilepsy in Spain. Expert review of pharmacoeconomics & outcomes research (Online). 1-10. https://doi.org/10.1080/14737167.2021.1838899S110WHO | Epilepsy: aISBN public health imperative. ISBN 978-92-4-151593-1. World Health Organization. 2019. Printed in Thailand.Ngugi, A. K., Kariuki, S. M., Bottomley, C., Kleinschmidt, I., Sander, J. W., & Newton, C. R. (2011). Incidence of epilepsy: A systematic review and meta-analysis. Neurology, 77(10), 1005-1012. doi:10.1212/wnl.0b013e31822cfc90Henning, O., Landmark, C. J., Henning, D., Nakken, K. O., & Lossius, M. I. (2019). Challenges in epilepsy—The perspective of Norwegian epilepsy patients. Acta Neurologica Scandinavica, 140(1), 40-47. doi:10.1111/ane.13098Brodie, M. J. (2005). Diagnosing and predicting refractory epilepsy. Acta Neurologica Scandinavica, 112(s181), 36-39. doi:10.1111/j.1600-0404.2005.00507.xGarcía-Ramos, R., Pastor, A. G., Masjuan, J., Sánchez, C., & Gil, A. (2011). FEEN: Informe sociosantario FEEN sobre la epilepsia en España. Neurología, 26(9), 548-555. doi:10.1016/j.nrl.2011.04.002Kwan, P., & Brodie, M. J. (2000). Early Identification of Refractory Epilepsy. New England Journal of Medicine, 342(5), 314-319. doi:10.1056/nejm200002033420503Brodie, M. J. (2008). Epilepsy: randomised trials and genetic tribulations. The Lancet Neurology, 7(1), 7-8. doi:10.1016/s1474-4422(07)70301-0French, J. A. (2006). Refractory Epilepsy: One Size Does Not Fit All. Epilepsy Currents, 6(6), 177-180. doi:10.1111/j.1535-7511.2006.00137.xLaxer, K. D., Trinka, E., Hirsch, L. J., Cendes, F., Langfitt, J., Delanty, N., … Benbadis, S. R. (2014). The consequences of refractory epilepsy and its treatment. Epilepsy & Behavior, 37, 59-70. doi:10.1016/j.yebeh.2014.05.031Giordano, C., Marchiò, M., Timofeeva, E., & Biagini, G. (2014). Neuroactive Peptides as Putative Mediators of Antiepileptic Ketogenic Diets. Frontiers in Neurology, 5. doi:10.3389/fneur.2014.00063European Medicines Agency. Committee for Medicinal Products for Human Use (CHMP). Briviact brivaracetam. Assessment Report EMA/CHMP/822086/2015 Nov.Markham, A. (2016). Brivaracetam: First Global Approval. Drugs, 76(4), 517-522. doi:10.1007/s40265-016-0555-6Willems, L. M., Bauer, S., Rosenow, F., & Strzelczyk, A. (2019). Recent advances in the pharmacotherapy of epilepsy: brivaracetam and perampanel as broad-spectrum antiseizure drugs for the treatment of epilepsies and status epilepticus. Expert Opinion on Pharmacotherapy, 20(14), 1755-1765. doi:10.1080/14656566.2019.1637420Craig, D., Rice, S., Paton, F., Fox, D., & Woolacott, N. (2013). Retigabine for the Adjunctive Treatment of Adults with Partial-Onset Seizures in Epilepsy with and without Secondary Generalization. PharmacoEconomics, 31(2), 101-110. doi:10.1007/s40273-012-0018-1Charokopou, M., Harvey, R., Srivastava, K., Brandt, C., & Borghs, S. (2019). Relative performance of brivaracetam as adjunctive treatment of focal seizures in adults: a network meta-analysis. Current Medical Research and Opinion, 35(8), 1345-1354. doi:10.1080/03007995.2019.1584501Chhatwal J. Changing cycle lengths in state-transition models: doing it the right way; [cited 2018 Jan 23]. Available from: https://www.ispor.org/News/Connections_methodology_state-transition-models.PDFMulhern, B., Rowen, D., Snape, D., Jacoby, A., Marson, T., Hughes, D., … Brazier, J. (2014). Valuations of epilepsy-specific health states: a comparison of patients with epilepsy and the general population. Epilepsy & Behavior, 36, 12-17. doi:10.1016/j.yebeh.2014.04.011Kristian, B., Wachtmeister, K., Stefan, F., & Forsgren, L. (2013). Retigabine as add-on treatment of refractory epilepsy - a cost-utility study in a Swedish setting. Acta Neurologica Scandinavica, 127(6), 419-426. doi:10.1111/ane.12077Vera-Llonch, M., Brandenburg, N. A., & Oster, G. (2008). Cost-effectiveness of Add-on Therapy with Pregabalin in Patients with Refractory Partial Epilepsy. Epilepsia, 49(3), 431-437. doi:10.1111/j.1528-1167.2007.01279.xSimoens, S. (2010). Pharmacoeconomics of anti-epileptic drugs as adjunctive therapy for refractory epilepsy. Expert Review of Pharmacoeconomics & Outcomes Research, 10(3), 309-315. doi:10.1586/erp.10.18Wijnen, B. F. M., van Mastrigt, G. A. P. G., Evers, S. M. A. A., Gershuni, O., Lambrechts, D. A. J. E., Majoie, M. H. J. M., … de Kinderen, R. J. A. (2017). A systematic review of economic evaluations of treatments for patients with epilepsy. Epilepsia, 58(5), 706-726. doi:10.1111/epi.13655Boeck, J. D., Verpoorten, K., Luyten, K., & Coninx, K. (2007). A Comparison between Decision Trees and Markov Models to Support Proactive Interfaces. 18th International Conference on Database and Expert Systems Applications (DEXA 2007). doi:10.1109/dexa.2007.94Zhang, Y., Wu, H., Denton, B. T., Wilson, J. R., & Lobo, J. M. (2017). Probabilistic sensitivity analysis on Markov models with uncertain transition probabilities: an application in evaluating treatment decisions for type 2 diabetes. Health Care Management Science, 22(1), 34-52. doi:10.1007/s10729-017-9420-8Swallow, E., Fang, A., Signorovitch, J., Plumb, J., & Borghs, S. (2017). Can Matching-Adjusted Indirect Comparison Methods Mitigate Placebo Response Differences Among Patient Populations in Adjunctive Trials of Brivaracetam and Levetiracetam? CNS Drugs, 31(10), 899-910. doi:10.1007/s40263-017-0462-8Malyshkina NV, Mannering FL. Markov switching multinomial logit model: an application to accident injury severities; 2008 [cited 2019 Sep 25]. Available from: http://arxiv.org/abs/0811.3644Hawkins, N., Epstein, D., Drummond, M., Wilby, J., Kainth, A., Chadwick, D., & Sculpher, M. (2005). Assessing the Cost-Effectiveness of New Pharmaceuticals in Epilepsy in Adults: The Results of a Probabilistic Decision Model. Medical Decision Making, 25(5), 493-510. doi:10.1177/0272989x05280559Agencia Española del Medicamento. Utilización de medicamentos antiepilépticos en España durante el periodo 2008–2016 [Internet]; 2017 [cited 2019 Sep 25]. Available from: https://www.aemps.gob.es/medicamentosUsoHumano/observatorio/docs/antiepilepticos-periodo-2008-2016.pdfMegiddo, I., Colson, A., Chisholm, D., Dua, T., Nandi, A., & Laxminarayan, R. (2016). Health and economic benefits of public financing of epilepsy treatment in India: An agent‐based simulation model. Epilepsia, 57(3), 464-474. doi:10.1111/epi.13294De Andrés-Nogales, F., Oyagüez, I., Álvarez-Sala, L. A., García-Bragado, F., Navarro, A., González, P., … Soto, J. (2017). Análisis coste-efectividad y coste-utilidad de apixaban frente a dabigatrán y rivaroxaban en el tratamiento y prevención secundaria del tromboembolismo venoso. PharmacoEconomics Spanish Research Articles, 14(1), 7-18. doi:10.1007/s40277-016-0064-8Fricke-Galindo, I., Jung-Cook, H., LLerena, A., & López-López, M. (2018). Farmacogenética de reacciones adversas a fármacos antiepilépticos. Neurología, 33(3), 165-176. doi:10.1016/j.nrl.2015.03.005Steinhoff, B. J., Bacher, M., Bucurenciu, I., Hillenbrand, B., Intravooth, T., Kornmeier, R., … Staack, A. M. (2017). Real-life experience with brivaracetam in 101 patients with difficult-to-treat epilepsy—A monocenter survey. Seizure, 48, 11-14. doi:10.1016/j.seizure.2017.03.010De Kinderen, R. J. A., Wijnen, B. F. M., van Breukelen, G., Postulart, D., Majoie, M. H. J. M., Aldenkamp, A. P., & Evers, S. M. A. A. (2016). From clinically relevant outcome measures to quality of life in epilepsy: A time trade-off study. Epilepsy Research, 125, 24-31. doi:10.1016/j.eplepsyres.2016.05.005Cortés, J.-C., Navarro-Quiles, A., Romero, J.-V., & Roselló, M.-D. (2017). Randomizing the parameters of a Markov chain to model the stroke disease: A technical generalization of established computational methodologies towards improving real applications. Journal of Computational and Applied Mathematics, 324, 225-240. doi:10.1016/j.cam.2017.04.04

Análisis del somatotipo de jugadores juveniles de fútbol asociación

The anthropometric characteristics of the subjects in association football were rarely considered in the selection of young soccer players in relation to their positions on the pitch. At present, in this sport it is becoming more and more frequent, as well as adding variables that contribute to the improvement of sports performance. Therefore, the main objective of this research is to identify and analyze the somatotype of amateur level players enrolled in the delfines academy who participate in the Veracruz soccer league, within the selection criteria of the participants is that they are in the age range of 14-17 years, they were evaluated for body composition through the bioimpedance technique (tanita tbf 300a, manual), with this the values ​​of weight, height, and BMI were obtained. Likewise, the anthropometry technique was obtained to obtain a complete profile of each player taking as a reference the calculation of the Heath - Carter somatotype, one of the results obtained is the prevalence of the endomorph somatotype for the forwards (2.87 ± 0. 76), defenders (2.99±0.55) and midfielders (2.55±0.47) and mesomorph: forwards (5.34±1.17), defenders (5.86±1.55) and midfielders (4.71±0.67), It was shown that the means present less mesomorphy and greater ectomorphy with (3.64±1.29). It is concluded from the results obtained that the predominance is of the balanced mesomorphic component, a situation that coincides with the results of other investigations, where the players of the amateur sector and professional soccer players according to the position they occupy on the pitch presenting a somatotype similar to those found in the studyLas características antropométricas de los sujetos en el fútbol asociación pocas veces eran consideradas en la selección de los jóvenes futbolistas en relación con sus posiciones dentro del terreno de juego. En la actualidad, en este deporte se hace cada vez más frecuente, así como sumar variables que coadyuvan a la mejora del rendimiento deportivo. Por tanto, el objetivo principal de esta investigación es identificar y analizar el somatotipo de jugadores de nivel amateur inscritos en la academia delfines que participa en la liga veracruzana de fútbol, dentro de los criterios de selección de los participantes es que estén en el rango de edad de 14-17 años, a ellos se les evaluación de composición corporal a través de la técnica de bioimpedancia (tanita tbf 300a, manual), con ello se obtuvieron los valores de peso, talla, IMC. Así mismo se utilizó la técnica de antropometría para obtener un perfil completo de cada jugador tomando como referencia el cálculo del somatotipo de Heath – Carter, alguno de los resultados obtenidos es la prevalencia del somatotipo de endomorfo para los delanteros (2,87±0,76), defensas (2.99±0,55) y medios campistas (2,55±0,47) y mesomorfo: delanteros (5,34±1,17), defensas (5,86±1,55) y medios campistas (4,71±0,67), Se observó que los medios presentan menor mesomorfia y mayor ectomorfia con (3,64 ±1,29). Se concluye por los resultados obtenidos que la predominancia es del componente mesomórfico balanceado, situación que coinciden con los resultados de otras investigaciones, donde los jugadores del sector amateur y jugadores de fútbol profesional de acuerdo a la posición que ocupan en el terreno de juego presentan un somatotipo similar a los hallazgos en el estudio

COVID-19 pandemic on coronary artery and cerebrovascular diseases in Southern Spain: interrupted time series analysis

Objective: Healthcare systems have been put under intense pressure by the COVID-19 pandemic, although some studies have shown a decline in hospital admissions for cardiovascular and cerebrovascular diseases during the first and second wave of the pandemic. In addition, studies analyzing gender and procedural differences are scarce. The present study aimed to determine the impact of the pandemic on hospital admissions for acute myocardial infarction (AMI) and cerebrovascular disease (CVD) in Andalusia (Spain) and analyzed differences by gender and by percutaneous coronary interventions performed. Patients and methods: An interrupted time series analysis of AMI and CVD hospital admissions in Andalusia (Spain) was carried out to measure the impact of the COVID-19 outbreak. AMI and CVD cases admitted daily in public hospitals of Andalusia between January 2018 and December 2020 were included. Results: During the pandemic, significant reductions in AMI [-19%; 95% confidence interval (CI): (-29%, -9%), p<0.001] and CVD [-17%; 95% CI: (-26%, -9%); p<0.01] in daily hospital admissions were observed. Differences were also produced according to the diagnosis (ST-Elevation Myocardial Infarction, Non-ST-Elevation Myocardial Infarction, other AMI and stroke), with a greater reduction in females for AMI and in males for CVD. Although there were more percutaneous coronary interventions during the pandemic, no significant reductions were observed. Conclusions: A decline in AMI and CVD daily hospital admissions during the first and second wave of COVID-19 pandemic was noted. Gender differences were observed, but no clear impact was observed in percutaneous interventions

Quantum Non-Demolition Detection of Strongly Correlated Systems

Preparation, manipulation, and detection of strongly correlated states of quantum many body systems are among the most important goals and challenges of modern physics. Ultracold atoms offer an unprecedented playground for realization of these goals. Here we show how strongly correlated states of ultracold atoms can be detected in a quantum non-demolition scheme, that is, in the fundamentally least destructive way permitted by quantum mechanics. In our method, spatially resolved components of atomic spins couple to quantum polarization degrees of freedom of light. In this way quantum correlations of matter are faithfully mapped on those of light; the latter can then be efficiently measured using homodyne detection. We illustrate the power of such spatially resolved quantum noise limited polarization measurement by applying it to detect various standard and "exotic" types of antiferromagnetic order in lattice systems and by indicating the feasibility of detection of superfluid order in Fermi liquids.Comment: Published versio