Intrinsic noise and two-dimensional maps: Quasicycles, quasiperiodicity, and chaos

We develop a formalism to describe the discrete-time dynamics of systems containing an arbitrary number of interacting species. The individual-based model, which forms our starting point, is described by a Markov chain, which in the limit of large system sizes is shown to be very well-approximated by a Fokker-Planck-like equation, or equivalently by a set of stochastic difference equations. This formalism is applied to the specific case of two species: one predator species and its prey species. Quasi-cycles --- stochastic cycles sustained and amplified by the demographic noise --- previously found in continuous-time predator-prey models are shown to exist, and their behavior predicted from a linear noise analysis is shown to be in very good agreement with simulations. The effects of the noise on other attractors in the corresponding deterministic map, such as periodic cycles, quasiperiodicity and chaos, are also investigated.Comment: 21 pages, 12 figure

Suppressing escape events in maps of the unit interval with demographic noise

We explore the properties of discrete-time stochastic processes with a bounded state space, whose deterministic limit is given by a map of the unit interval. We find that, in the mesoscopic description of the system, the large jumps between successive iterates of the process can result in probability leaking out of the unit interval, despite the fact that the noise is multiplicative and vanishes at the boundaries. By including higher-order terms in the mesoscopic expansion, we are able to capture the non-Gaussian nature of the noise distribution near the boundaries, but this does not preclude the possibility of a trajectory leaving the interval. We propose a number of prescriptions for treating these escape events, and we compare the results with those obtained for the metastable behavior of the microscopic model, where escape events are not possible. We find that, rather than truncating the noise distribution, censoring this distribution to prevent escape events leads to results which are more consistent with the microscopic model. The addition of higher moments to the noise distribution does not increase the accuracy of the final results, and it can be replaced by the simpler Gaussian noise.Comment: 14 pages, 13 figure

Reduction of a metapopulation genetic model to an effective one island model

We explore a model of metapopulation genetics which is based on a more ecologically motivated approach than is frequently used in population genetics. The size of the population is regulated by competition between individuals, rather than by artificially imposing a fixed population size. The increased complexity of the model is managed by employing techniques often used in the physical sciences, namely exploiting time-scale separation to eliminate fast variables and then constructing an effective model from the slow modes. Remarkably, an initial model with 2$\mathcal{D}$ variables, where $\mathcal{D}$ is the number of islands in the metapopulation, can be reduced to a model with a single variable. We analyze this effective model and show that the predictions for the probability of fixation of the alleles and the mean time to fixation agree well with those found from numerical simulations of the original model.Comment: 16 pages, 4 figures. Supplementary material: 22 pages, 3 figure

Mapping Climate Change Research via Open Repositories & AI: advantages and limitations for an evidence-based R&D policy-making

In the last few years, several initiatives have been starting to offer access to research outputs data and metadata in an open fashion. The platforms developed by those initiatives are opening up scientific production to the wider public and they can be an invaluable asset for evidence-based policy-making in Science, Technology and Innovation (STI). These resources can indeed facilitate knowledge discovery and help identify available R&D assets and relevant actors within specific research niches of interest. Ideally, to gain a comprehensive view of entire STI ecosystems, the information provided by each of these resources should be combined and analysed accordingly. To ensure so, at least a certain degree of interoperability should be guaranteed across data sources, so that data could be better aggregated and complemented and that evidence provided towards policy-making is more complete and reliable. Here, we study whether this is the case for the case of mapping Climate Action research in the whole Denmark STI ecosystem, by using 4 popular open access STI data sources, namely OpenAire, Open Alex, CORDIS and Kohesio.Comment: This is an extended version of paper 10.1007/978-3-031-16802-4_52, which was accepted at the International Conference on Theory and Practice of Digital Libraries (TPDL) 2022. arXiv admin note: text overlap with arXiv:2209.0892

El Principio de Autonomía en la Atención Médica en Colombia y Perú

Issues about ethics and the principle of autonomy in the relationships between health professionals and patients are analyzed with a comprehensive view of the Peruvian and Colombian regulations and jurisprudence, in order to allow dialogue in relation to the responses given around health information. In addition to the above, an analysis is made of the phenomenon of the rights and duties of the parties involved in health care, traditionally focused on the patient but which must recognize the active participation of health professionals. Finally, it addresses the recognition of the principle of autonomy in the doctor-patient relationship as the fundamental axis of the doctor-user relationship, protected by legal systems as the basis of health protection as a fundamental right and as a social right.Las cuestiones acerca de la ética y el principio de autonomía en las relaciones de los profesionales de la salud y los pacientes se analizan con una mirada comprensiva de la normativa y jurisprudencia peruana y colombiana, con el fin de permitir el diálogo en relación con las respuestas que se dan en torno a la información en salud. Además de lo anterior, se realiza un análisis del fenómeno de los derechos y deberes de las partes intervinientes en la atención de la salud, enfocadas tradicionalmente en el paciente pero que deben reconocer la participación activa de profesionales sanitarios. Finalmente aborda el reconocimiento del principio de autonomía en la relación médico-paciente como eje fundamental de la relación médico – usuario, cobijados por los ordenamientos jurídicos como base de la protección de la salud como derecho fundamental y como derecho social

Effect of the concentration of magnetite on the structure, electrical and magnetic properties of a polyester resin-based composite

Se reporta el efecto de la concentración de polvos de magnetita (Fe3O4) sobre las propiedades eléctricas y magnéticas de un material compuesto a base de resina de poliéster termoestable. Las muestras se elaboraron mediante el método de colado manual en concentraciones de: 60-40, 70-30, 80-20, 90-10 y 100-0 (% en peso), donde la fase mayoritaria es la resina y la minoritaria los óxidos de Fe3O4. La estructura cristalina se estudió usando la técnica de difracción de rayos X y la caracterización superficial tuvo lugar a través de la técnica de microscopía electrónica de barrido. Se midió la respuesta eléctrica por medio de curvas de polarización eléctrica en función del campo eléctrico y de resistividad eléctrica volumétrica a través de un electrómetro. La respuesta magnética se determinó mediante curvas de magnetización en función de la intensidad de campo magnético aplicado y en función de la temperatura. El análisis estructural indica que el porcentaje de cristalinidad aumenta a medida que se adiciona la concentración de Fe3O4 a las muestras. La caracterización eléctrica del material evidencia que la resistividad volumétrica disminuye con el incremento de magnetita, mostrando una transición aislante-conductor, con valores de la constante dieléctrica cada vez mayores. La caracterización magnética evidencia un aumento lineal de la magnetización de saturación y del momento magnético en función de la cantidad de magnetita adicionada a la matriz polimérica, mientras que la coercitividad evidencia comportamientos de materiales magnéticos blandos tanto en T˃TV como en T<TV, donde TV representa la temperatura de Verwey.This study reports the effect of the concentration of magnetite powders (Fe3O4) on the electrical and magnetic properties of a resin-based composite of thermoset polyester. The samples were prepared by the casting method at different concentrations: 60-40, 70-30, 80-20, 90-10 and 100-0 (% in weight), where the primary phase was resin and the secondary, Fe3O4 powders. The crystalline structure was studied using X-ray diffraction and surface characterization was carried out applying the scanning electron microscopy technique. The electrical response was measured by electric polarization curves as a function of the electric field; and the volumetric electrical resistivity, by an electrometer. The magnetic response was determined by magnetization curves as a function of temperature and intensity of the applied magnetic field. The structural analysis indicates that crystallinity increases as higher concentrations of Fe3O4 are added to the samples. The electrical characterization of the material reveals that the volumetric resistivity decreases as the content of magnetite increases. These reactions indicate an insulation-conductor transition with increasing dielectric constant values. The magnetic characterization presents a linear increase of the saturation of magnetization and magnetic moment as a function of the amount of magnetite added to the polymer matrix, whereas the coercivity shows behaviors of soft magnetic materials for T ˃ Tv and for T < Tv, where Tv represents the temperature of Verwey

Reseñas

La literatura como escudo de la caverna: a propósito de La Virgen de los sicarios. / The analysis and use of financial Statements. / El capital intelectual: cómo identificar y calcular el valor inexplotado de los recursos intangibles de su empresa. / Klaus Meyer (1998), Direct investment in economies in transition, serie new horizons in international business. / Administración de operaciones y producción: calidad total y respuesta sensible rápida. / Las políticas públicas. Segunda edición adicionada con el concepto de "think thanks". / Diseño de organizaciones: tensiones y paradojas. / El marketing de las naciones: una aproximación estratégica a la creación de la riqueza nacional. / Compañía ilimitada: reportaje a los grandes grupos económicos. / Effective coaching. / Ingeniería industrial y administración: una nueva perspectiva. / The global agenda (issues and perspectives). / Administración de organizaciones: productividad y eficacia. / Moral para el siglo XXI

The Role of miR-107 in Prostate Cancer: A Review and Experimental Evidence

Over the past two decades, several research groups have focused on the functioning of microRNAs (miRNAs), because many of them function as positive or negative endogenous regulators of processes that alter during the development of cancer. Prostate cancer is the second most commonly occurring cancer in men. New biomarkers are needed to support the diagnosis of prostate cancer. Although it is necessary to deepen the research on this molecule to explore its potential utility in the diagnosis, follow-up, and prognosis of cancer, our results support a role of miR-107 in the signaling cascades that allow cancer progression, and as shown here, in the progression of Prostate Cancer (PCa). These findings strongly suggest that miR-107 may be a potential circulating biomarker for the diagnosis and prognosis of prostate cancer

Gliomas difusos en áreas elocuentes: avances diagnósticos y terapéuticos

Objetivo: presentar los avances diagnósticos, moleculares y radiológicos, así como en las estrategias terapéuticas para gliomas difusos en los últimos 5 años (2018-2023) en la Fundación Universitaria de Ciencias de la Salud (FUCS), Bogotá D.C., Colombia. Materiales y métodos: se describen las técnicas diagnósticas y terapéuticas utilizadas para gliomas difusos con casos ilustrativos. Resultados: se muestran los avances de las herramientas diagnósticas y terapéuticas para el manejo de gliomas difusos. Discusión: en los últimos 5 años se ha avanzado en la clasificación, diagnóstico y tratamiento de los gliomas difusos, gracias a los avances tecnológicos como los marcadores moleculares, la tractografía y la fusión de imágenes para la neuronavegación y las técnicas de estimulación cortical. Esto ha permitido que el tratamiento de los pacientes con dichos tumores mejore la tasa de morbilidad, la calidad de vida libre de enfermedad y la supervivencia global. Conclusiones: las técnicas de diagnóstico como la tractografía, la fusión integral de imágenes intraoperatorias y el mapeo cerebral electrofisiológico con estimulación cortical y subcortical han mejorado el diagnóstico y tratamiento de los gliomas difusos

Systematic Collaborative Reanalysis of Genomic Data Improves Diagnostic Yield in Neurologic Rare Diseases

Altres ajuts: Generalitat de Catalunya, Departament de Salut; Generalitat de Catalunya, Departament d'Empresa i Coneixement i CERCA Program; Ministerio de Ciencia e Innovación; Instituto Nacional de Bioinformática; ELIXIR Implementation Studies (CNAG-CRG); Centro de Investigaciones Biomédicas en Red de Enfermedades Raras; Centro de Excelencia Severo Ochoa; European Regional Development Fund (FEDER).Many patients experiencing a rare disease remain undiagnosed even after genomic testing. Reanalysis of existing genomic data has shown to increase diagnostic yield, although there are few systematic and comprehensive reanalysis efforts that enable collaborative interpretation and future reinterpretation. The Undiagnosed Rare Disease Program of Catalonia project collated previously inconclusive good quality genomic data (panels, exomes, and genomes) and standardized phenotypic profiles from 323 families (543 individuals) with a neurologic rare disease. The data were reanalyzed systematically to identify relatedness, runs of homozygosity, consanguinity, single-nucleotide variants, insertions and deletions, and copy number variants. Data were shared and collaboratively interpreted within the consortium through a customized Genome-Phenome Analysis Platform, which also enables future data reinterpretation. Reanalysis of existing genomic data provided a diagnosis for 20.7% of the patients, including 1.8% diagnosed after the generation of additional genomic data to identify a second pathogenic heterozygous variant. Diagnostic rate was significantly higher for family-based exome/genome reanalysis compared with singleton panels. Most new diagnoses were attributable to recent gene-disease associations (50.8%), additional or improved bioinformatic analysis (19.7%), and standardized phenotyping data integrated within the Undiagnosed Rare Disease Program of Catalonia Genome-Phenome Analysis Platform functionalities (18%)