Cosmic inhomogeneities in the early Universe: A numerical relativity approach

Cosmic inflation is arguably the most favoured paradigm of the very early Universe. It postulates an early phase of fast, nearly exponential, and accelerated expansion. Inflationary models are capable of explaining the overall flatness and homogeneity of today's Universe at large scales. Despite being widely accepted by the physics community, these models are not absent from criticism. In scalar field inflation, a necessary condition to begin inflation is the requirement of a Universe dominated by the field's potential, which implies a subdominant contribution from the scalar field dynamics. This has originated to large amounts of scientific debate and literature on the naturalness, and possible fine-tuning of the initial conditions for inflation. Another controversial issue concerns the end of inflation, and the fact that a preheating mechanism is necessary to originate the hot big bang plasma after inflation. In this thesis, we present full general relativistic simulations to study these two problems, with a particular focus on the Starobinsky and Higgs models of inflation. First, we consider the fine-tuning problem of beginning inflation from a highly dynamical and inhomogeneous "preinflation" epoch in the single-field case. In our second study, we approach the multifield paradigm of preinflation, together and consistently, with the preheating phase. These investigations confirm the robustness of these inflationary models to generic initial conditions, while putting in evidence the non-negligible gravitational effects during preheating. At the end of the manuscript, we discuss potential applications of numerical simulations in cosmology, including our preliminary investigations on primordial black hole formation.Comment: PhD thesis of Cristian Joana defended in October 2022. Chapters 5 and 6 corresponds to articles arXiv:2011.12190 and arXiv:2202.07604, respectivel

Inhomogeneous initial conditions for inflation: A wibbly-wobbly timey-wimey path to salvation

We use the 3+1 formalism of numerical relativity to investigate the robustness of Starobinsky and Higgs inflation to inhomogeneous initial conditions, in the form of either field gradient or kinetic energy density. Sub-Hubble and Hubble-sized fluctuations generically lead to inflation after an oscillatory phase between gradient and kinetic energies. Hubble-sized inhomogeneities also produce contracting regions that may end up forming primordial black holes, subsequently diluted by inflation. We analyse the dynamics of the preinflation era and the generation of vector and tensor fluctuations. Our analysis further supports the robustness of inflation to any size of inhomogeneity, in the field, velocity or equation of state. At large field values, the preinflation dynamics only marginally depends on the field potential and it is expected that such behaviour is universal and applies to any inflation potential of plateau-type, favoured by CMB observations after Planck.Comment: 17 pages, 9 figures. Improved discussions, references adde

Multistability, phase diagrams, and intransitivity in the Lorenz-84 low-order atmospheric circulation model

We report phase diagrams detailing the intransitivity observed in the climate scenarios supported by a prototype atmospheric general circulation model, namely, the Lorenz-84 low-order model. So far, this model was known to have a pair of coexisting climates described originally by Lorenz. Bifurcation analysis allows the identification of a remarkably wide parameter region where up to four climates coexist simultaneously. In this region the dynamical behavior depends crucially on subtle and minute tuning of the model parameters. This strong parameter sensitivity makes the Lorenz-84 model a promising candidate of testing ground to validate techniques of assessing the sensitivity of low-order models to perturbations of parameters

Adaptación y validación del cuestionario de susceptibilidad, beneficios y barreras ante el cribado con mamografía

ResumenObjetivosAdaptar una «escala de creencias» sobre el cáncer de mama al castellano, evaluando su validez y reproducibilidad.MétodosValidación de una escala de 3 dimensiones –susceptibilidad, beneficios y barreras– con respuestas tipo Likert, en un estudio de casos y controles, donde los casos eran las mujeres no participantes en un programa de cribado de cáncer de mama y los controles las participantes. Se realizó un proceso de traducción-retrotraducción y un comité técnico analizó las discrepancias. Se pilotó la comprensión en 17 mujeres. Participaron en el estudio 274 mujeres y a 32 de ellas se les repitió el cuestionario en el intervalo de un mes para valorar la reproducibilidad.ResultadosEl coeficiente de correlación intraclase fue de 0,89, 0,70 y 0,90, y el coeficiente alfa de Cronbach de 0,71, 0,48 y 0,57 para susceptibilidad, beneficios y barreras, respectivamente. Respecto a la validez de constructo, del análisis factorial exploratorio se extrajeron 3 factores, lo que explicaba un 34% de la varianza. El análisis factorial confirmatorio señala un ajuste al límite de los datos al modelo teórico. Las mujeres de más edad perciben menos susceptibilidad al cáncer de mama y declaran más barreras para hacerse una mamografía. Las de menor nivel de estudios perciben más barreras. La escala no ha mostrado su capacidad para predecir la participación en el programa.ConclusionesLa escala presenta problemas de validez y homogeneidad. Las dimensiones de beneficios y barreras necesitan un proceso de adaptación y validación profunda para su utilización.AbstractObjectivesTo adapt the «health belief model» on breast cancer screening to Spanish, and to asses its validity and reliability.MethodsWe assessed validation of a scale with 3 dimensions (susceptibility, benefits and barriers) with Likert responses in a case-control study. Cases were women not participating in a breast cancer screening program and controls consisted of participating women. A process of translation and back-translation was carried out and a technical committee analyzed discrepancies. Comprehension was tested in 17 women. Two hundred seventy-four women participated in the study. In 32 of these women, the questionnaire was administered twice after a 1-month interval to estimate its reliability.ResultsThe intraclass correlation coefficients were 0.89, 0.70 and 0.90, and Cronbach's alpha coefficient was 0.71, 0.48 and 0.57 for susceptibility, benefits and barriers, respectively. Construct validity: from the factorial analysis, 3 factors were obtained explaining 34% of the variance. The confirmatory factorial analysis indicated acceptable goodness-of-fit of the data to the theoretical model. Older women perceived less susceptibility to breast cancer as well as greater barriers to attending screening. Women with a lower educational level perceived greater barriers. The scale did not seem to predict adherence to the program.ConclusionsThe adapted scale presents problems of validity and internal consistency. The dimensions of benefits and barriers require thorough adaptation and validation before the scale is used in Spanish women

Determinantes genéticos y sus mecanismos de acción implicados en la resistencia bacteriana a metales pesados: una revisión.

Se identificó y describió los principales determinantes genéticos implicados en la resistencia bacteriana a metales pesados reportados en la literatura, así como sus usos a nivel biotecnológico y ambiental. Se llevó a cabo una revisión bibliográfica de información de los últimos 10 años encontrados en revistas con indexación SJR disponibles en las diferentes bases de datos; bosquejando la situación actual del conocimiento sobre el tema y realizando comparaciones cualitativas entre las investigaciones seleccionadas. Las bacterias se encuentran en constante evolución y se vuelven más resistentes gracias a la adquisición de genes que les permite hacer frente a los efectos tóxicos de los metales. Por ello, se compiló desde varios autores los determinantes genéticos de resistencia bacteriana para los metales, como el arsénico, mercurio, cromato y cadmio siendo respectivamente: ars, mer, chr, cad y czc; estos sistemas pueden localizarse en el cromosoma o plásmidos de las bacterias. Se describe el mecanismo de acción que codifica cada determinante, siendo la regulación y la desintoxicación enzimática los principales mecanismos. Finalmente, se comparó las aplicaciones biotecnológicas y ambientales de los determinantes, encontrándose un amplio uso en la construcción de biosensores y organismos genéticamente modificados.The main genetic determinants involved in bacterial resistance to heavy metals reported in the literature were identified and described, as well as their uses at biotechnological and environmental levels. A bibliographic review of information from the last ten years found in SJR indexed journals available in different databases was carried out, outlining the current state of knowledge on the subject and making qualitative comparisons between the selected researches. Bacteria are constantly evolving and becoming more resistant thanks, to the acquisition of genes that allow them to cope with the toxic effects of metals. Therefore, the genetic determinants of bacterial resistance to metals such as arsenic, mercury, chromate and cadmium were compiled from several authors, being respectively: ars, mer, chr, cad and czc; these systems can be located in the chromosome and plasmids of bacteria. The mechanism of action encoded by each determinant is described, mainly regulation and enzymatic detoxification. Finally, the biotechnological and environmental applications of the determinants were compared, finding wide use in the construction of biosensors and genetically modified organisms

Cows vocalization and behavioral characterization during eutocic and dystocic calvings

Oral session 3[EN] Calving is a painful and stressful event for dairy cows. Continuous monitoring can provide quick and accurate assistance to the cow, reducing stress, pain, and preventing calving difficulties (dystocia). Vocalizations can provide information on cow welfare problems, such as pain. The aims of the current study were: (1) to characterize cows' vocalizations before and during calving and (2) to determine the relationship between cow vocalizations and painrelated behavior in eutocic and dystocic calvings

Perturbation theory/machine learning model of ChEMBL data for dopamine targets: docking, synthesis, and assay of new l-prolyl-l-leucyl-glycinamide peptidomimetics

[Abstract] Predicting drug–protein interactions (DPIs) for target proteins involved in dopamine pathways is a very important goal in medicinal chemistry. We can tackle this problem using Molecular Docking or Machine Learning (ML) models for one specific protein. Unfortunately, these models fail to account for large and complex big data sets of preclinical assays reported in public databases. This includes multiple conditions of assays, such as different experimental parameters, biological assays, target proteins, cell lines, organism of the target, or organism of assay. On the other hand, perturbation theory (PT) models allow us to predict the properties of a query compound or molecular system in experimental assays with multiple boundary conditions based on a previously known case of reference. In this work, we report the first PTML (PT + ML) study of a large ChEMBL data set of preclinical assays of compounds targeting dopamine pathway proteins. The best PTML model found predicts 50000 cases with accuracy of 70–91% in training and external validation series. We also compared the linear PTML model with alternative PTML models trained with multiple nonlinear methods (artificial neural network (ANN), Random Forest, Deep Learning, etc.). Some of the nonlinear methods outperform the linear model but at the cost of a notable increment of the complexity of the model. We illustrated the practical use of the new model with a proof-of-concept theoretical–experimental study. We reported for the first time the organic synthesis, chemical characterization, and pharmacological assay of a new series of l-prolyl-l-leucyl-glycinamide (PLG) peptidomimetic compounds. In addition, we performed a molecular docking study for some of these compounds with the software Vina AutoDock. The work ends with a PTML model predictive study of the outcomes of the new compounds in a large number of assays. Therefore, this study offers a new computational methodology for predicting the outcome for any compound in new assays. This PTML method focuses on the prediction with a simple linear model of multiple pharmacological parameters (IC50, EC50, Ki, etc.) for compounds in assays involving different cell lines used, organisms of the protein target, or organism of assay for proteins in the dopamine pathway.Ministerio de Economía y Competitividad; CTQ2016-74881-PGobierno Vasco; IT1045-16Xunta de Galicia; GPC2014/003Xunta de Galicia; CN 2012/069Xunta de Galicia; ED431D 2017/16Xunta de Galicia; ED431D 2017/23Xunta de Galicia; GRC2014/049Xunta de Galicia; ED431D 2017/2

Satisfaction with Life Scale: Evidences of validity and reliability among Portuguese college students

Este artigo apresenta novos dados sobre a precisão e validade dos resultados na Escala de Satisfação com a Vida (SWLS) junto de estudantes universitários. Uma amostra de 545 estudantes provenientes de uma universidade pública portuguesa foi considerada. A unidimensionalidade da escala foi confirmada, apresentando todos os itens cargas fatoriais superiores a .60, ainda que a sua invarância em função do género dos estudantes não se tenha confirmado, desaconselhando comparações de resultados entre homens e mulheres. As correlações moderadas em sentido positivo e negativo com os afetos positivos e negativos avaliados através da Escala de Afetos Positivos e Negativos (PANAS) traduzem evidências de validade de critério. A consistência interna dos resultados nos cindo itens da ESV situou-se em .77, sendo considerada adequada até pelo número reduzido de itens.This paper presents new data on the reliability and validity of results in the Satisfaction With Life Scale (SWLS) among university students. A sample of 545 students from a Portuguese public university was considered. The unidimensionality of the scale was confirmed, with all factor loadings higher than .60, although their invariance according to the gender of the students was not confirmed, and it was not advisable to compare the results between men and women. Moderate positive and negative correlations with positive and negative affects assessed through the Positive and Negative Affect Schedule (PANAS) translate evidence of criterion validity. The internal consistency of the results in the fifth items of the ESV was .77, considered adequate face the reduced number of itemsFCT/SFRH/BD/117902/201

Might cows have accents? Acoustic characterization of calves vocalizations from two different geographical locations

Oral session 2[EN] The development of artificial intelligence algorithms and monitoring technologies has led to the increased use of sensors in animal production. Animal production stakeholders have emphasized the importance of non-invasive methods that provide accurate information without compromising the physical integrity of the animals. Animal vocalizations offer an opportunity to capture data of biological relevance without animal manipulation

Adaptación y validación del cuestionario de susceptibilidad, beneficios y barreras ante el cribado con mamografía

Objetivos: Adaptar una «escala de creencias» sobre el cáncer de mama al castellano, evaluando su validez y reproducibilidad. Métodos: Validación de una escala de 3 dimensiones -susceptibilidad, beneficios y barreras- con respuestas tipo Likert, en un estudio de casos y controles, donde los casos eran las mujeres no participantes en un programa de cribado de cáncer de mama y los controles las participantes. Se realizó un proceso de traducción-retrotraducción y un comité técnico analizó las discrepancias. Se pilotó la comprensión en 17 mujeres. Participaron en el estudio 274 mujeres y a 32 de ellas se les repitió el cuestionario en el intervalo de un mes para valorar la reproducibilidad. Resultados: El coeficiente de correlación intraclase fue de 0,89, 0,70 y 0,90, y el coeficiente alfa de Cronbach de 0,71, 0,48 y 0,57 para susceptibilidad, beneficios y barreras, respectivamente. Respecto a la validez de constructo, del análisis factorial exploratorio se extrajeron 3 factores, lo que explicaba un 34% de la varianza. El análisis factorial confirmatorio señala un ajuste al límite de los datos al modelo teórico. Las mujeres de más edad perciben menos susceptibilidad al cáncer de mama y declaran más barreras para hacerse una mamografía. Las de menor nivel de estudios perciben más barreras. La escala no ha mostrado su capacidad para predecir la participación en el programa. Conclusiones: La escala presenta problemas de validez y homogeneidad. Las dimensiones de beneficios y barreras necesitan un proceso de adaptación y validación profunda para su utilización