How AGN feedback drives the size growth of the first quasars

Quasars at $z \,=\, 6$ are powered by accretion onto supermassive black holes with masses $M_{\rm BH} \sim 10^9 \rm \, M_{\odot}$. Their rapid assembly requires efficient gas inflow into the galactic nucleus, sustaining black hole accretion at a rate close to the Eddington limit, but also high central star formation rates. Using a set of cosmological 'zoom-in' hydrodynamic simulations performed with the moving mesh code Arepo, we show that $z \,=\, 6$ quasar host galaxies develop extremely tightly bound stellar bulges with peak circular velocities $300$ - $500$ km s$^{-1}$ and half-mass radii $\approx 0.5 \, \rm kpc$. Despite their high binding energy, we find that these compact bulges expand at $z \, < \, 6$, with their half-mass radii reaching $\approx 5$ kpc by $z \, = \, 3$. The circular velocity drops by factors $\approx 2$ from their initial values to $200$ - $300$ km s$^{-1}$ at $z \, \approx \, 3$ and the stellar profile undergoes a cusp-core transformation. By tracking individual stellar populations, we find that the gradual expansion of the stellar component is mainly driven by fluctuations in the gravitational potential induced by bursty AGN feedback. We also find that galaxy size growth and the development of a cored stellar profile does not occur if AGN feedback is ineffective. Our findings suggest that AGN-driven outflows may have profound implications for the internal structure of massive galaxies, possibly accounting for their size growth, the formation of cored ellipticals as well as for the saturation of the $M_{\rm BH}$ - $\sigma_{\star}$ seen at high velocity dispersions $\sigma_{\star}$.Comment: 17 pages, 11 figures, 2 tables, accepted for publication in MNRA

Pharmaceutical Communication over Social Media Channels: 24/7 Management Challenges

Social media marketing is evolving rapidly and gaining popularity within academia and firms. This chapter highlights the major challenges posed by social media to the pharmaceutical industry, assessing the presence of major pharmaceutical firms on social media platforms such as Facebook, Twitter, and YouTube and characterizing their digital engagement strategies. This study gathered data from the top 20 pharmaceutical companies’ official websites, Facebook, Twitter, and YouTube accounts and examined variables such as Internet presence, engagement, fans/followers, and network structure. Findings from this study show that not all pharmaceutical firms are present on social media, and some platforms are used more than others. Notably, the digital engagement strategies varied between the analyzed social media platforms and remained similar on the two periods. Results also show that the level of engagement assessed was not associated with firm size. In several firms, the communication was mostly directed to the general public. Depending on the company, country-based communities were found. This work can be of interest to practitioners aiming to compare and assess their digital activity. It could also assist future researchers focusing on pharmaceutical social media marketing activity, since few researchers have analyzed this using more than one social networking site

The host dark matter haloes of the first quasars

If $z > 6$ quasars reside in rare, massive haloes, $\Lambda$CDM cosmology predicts they should be surrounded by an anomalously high number of bright companion galaxies. In this paper, I show that these companion galaxies should also move unusually fast. Using a new suite of cosmological, `zoom-in' hydrodynamic simulations, I here present predictions for the velocity distribution of quasar companion galaxies and its variation with quasar host halo mass at $z \, = \, 6$. Satellites accelerate as they approach the quasar host galaxy, producing a line-of-sight velocity profile that broadens as the distance to the quasar host galaxy decreases. This increase in velocity dispersion is particularly pronounced if the host halo mass is $\gtrsim 5 \times 10^{12} \, \rm M_\odot$. In this case, typical line-of-sight speeds rise to $\approx 500 \, \rm km \, s^{-1}$ at projected radii $\sim 10 \, \rm kpc$. For about $10\%$ of satellites, they should exceed $800 \, \rm km \, s^{-1}$, with $\approx 5\%$ of companions reaching line-of-sight speeds $\sim 1000 \, \rm km \, s^{-1}$. For lower host halo masses $\approx 5 \times 10^{11} - 10^{12} \, \rm M_\odot$, the velocity profile of companion galaxies is significantly flatter. In this case, typical line-of-sight velocities are $\approx 250 \, \rm km \, s^{-1}$ and do not exceed $\approx 500 \, \rm km \, s^{-1}$. A comparison with existing ALMA, JWST and MUSE line-of-sight velocity measurements reveals that observed $z > 6$ quasar companions closely follow the velocity distribution expected for a host halo with mass $\gtrsim 5 \times 10^{12} \, \rm M_\odot$, ruling out a light host halo. Finally, through an estimate of UV and [OIII] luminosity functions, I show that the velocity distribution more reliably discriminates between halo mass than companion number counts, which are strongly affected by cosmic variance.Comment: 13 pages, submitted to MNRAS (July 2023

Caracterização do perfil de lípidos polares da polpa da azeitona com recurso à lipidómica

The consumption of olives, the fruits of the olive tree (Olea europaea L.), in the form of table olives and olive oil has increased significantly in the last two decades worldwide. However, the nutritional value of this complex matrix rich in lipids, whose pulp represents ca. 75% of its dry weight, is not yet fully known. Its lipid fraction comprises essentially triacylglycerols but also free fatty acids, sterols and polar lipids. However, the profile of these polar lipids, such as phospholipids and glycolipids, compounds with various health benefits and bioactive properties, is practically unknown, with the need for their characterisation. As such, this study characterised the polar lipidome of the olive pulp of three varieties and two geographic regions through emerging techniques of high resolution and sensitivity, based on chromatography and mass spectrometry. The work began by extracting total lipids from the pulp, followed by fractionation of the total extract and characterisation of the polar lipid-rich fractions. The fractionation process by solid-phase extraction was tested, and the efficiency of this protocol in the recovery of polar lipids in qualitative and quantitative terms was confirmed. The analysis of the total lipid extract and polar lipid-rich fractions by thin-layer chromatography allowed verification of the pulp’s lipidome complexity. The analysis of the polar lipid-rich fractions by HILIC HPLC-ESI-MS/MS allowed the identification and structural characterization of one hundred and eighty-eight lipid species: one hundred and thirty-two phospholipids, thirty-five glycolipids, fifteen sphingolipids and six betaines. In addition to identifying several new molecular species, several lipid classes have also been reported in the olive pulp for the first time. This work has also revealed the fatty acid composition of the polar lipidome of the olive pulp, comprising monounsaturated, polyunsaturated, saturated, monohydroxy and dihydroxy fatty acyl chains. Finally, the polar lipid-based multivariate statistical analysis allowed the successful identification of lipid markers that can discriminate the botanical and or geographic origin of olives, thus demonstrating the uniqueness of the polar lipidome profile of each group of olives under study. With the identification of potentials bioactive lipids, this work has also allowed valuing the olive fruit as a beneficial food for health and several potential industrial applications such as the food, cosmetics, pharmaceuticals, nutraceutical and feed industries.O consumo da azeitona, fruto da oliveira (Olea europaea L.), na forma de azeitona de mesa e de azeite aumentou significativamente nas últimas duas décadas a nível mundial. Contudo, o valor nutricional desta matriz complexa e rica em lípidos, cuja polpa representa ca. 75 % do seu peso seco, ainda não é totalmente conhecido. A sua fração lipídica compreende essencialmente triacilgliceróis mas também ácidos gordos livres, esteróis e lípidos polares. No entanto, o perfil destes lípidos polares, como fosfolípidos e glicolípidos, compostos com diversos benefícios para a saúde e propriedades bioativas, é praticamente desconhecido, havendo a necessidade da sua caracterização. Como tal, este estudo caracterizou o lipidoma polar da polpa da azeitona de três variedades e duas regiões geográficas através de técnicas emergentes de alta resolução e sensibilidade, baseadas em cromatografia e espetrometria de massa. O trabalho começou pela extração dos lípidos totais da polpa, seguida pelo fracionamento do extrato total e caracterização da fração enriquecida em lípidos polares. O processo de fracionamento por extração em fase sólida foi testado e confirmou-se a eficiência deste protocolo na recuperação de lípidos polares em termos qualitativos e quantitativos. A análise do extrato lipídico total e das frações enriquecidas em lípidos polares por cromatografia em camada fina permitiu verificar a complexidade do lipidoma da polpa. A análise por HILIC HPLC-ESI-MS/MS da fração de lípidos polares permitiu a identificação e caracterização estrutural de cento e oitenta e oito espécies lipídicas: cento e trinta e dois fosfolípidos, trinta e cinco glicolípidos, quinze esfingolípidos e seis betaínas. Para além da identificação de diversas novas espécies moleculares, várias classes de lípidos foram reportadas na polpa da azeitona pela primeira vez. Este trabalho também revelou a composição em ácidos gordos do lipidoma polar da polpa de azeitona, compreendendo ácidos gordos monoinsaturados, polinsaturados, saturados, monohidroxi e dihidroxi. Por fim, a análise estatística multivariada permitiu identificar com sucesso marcadores lipídicos que conseguem discriminar a origem botânica e/ou geográfica das azeitonas, demonstrando assim a unicidade do perfil do lipidoma polar de cada grupo de azeitonas estudadas. Com a identificação de potenciais lípidos bioativos, este trabalho também permitiu valorizar a azeitona como um alimento benéfico para a saúde e com diversas potenciais aplicações industriais como as indústrias alimentar, cosmética, farmacêutica, nutracêutica e de rações.Mestrado em Biotecnologi

A Community-Driven Validation Service for Standard Medical Imaging Objects

Digital medical imaging laboratories contain many distinct types of equipment provided by different manufacturers. Interoperability is a critical issue and the DICOM protocol is a de facto standard in those environments. However, manufacturers' implementation of the standard may have non-conformities at several levels, which will hinder systems' integration. Moreover, medical staff may be responsible for data inconsistencies when entering data. Those situations severely affect the quality of healthcare services since they can disrupt system operations. The existence of software able to confirm data quality and compliance with the DICOM standard is important for programmers, IT staff and healthcare technicians. Although there are a few solutions that try to accomplish this goal, they are unable to deal with certain situations that require user input. Furthermore, these cases usually require the setup of a working environment, which makes the sharing of validation information more difficult. This article proposes and describes the development of a Web DICOM validation service for the community. This solution requires no configuration by the user, promotes validation results share-ability in the community and preserves patient data privacy since files are de-identified on the client side.Comment: Computer Standards & Interfaces, 201

Ciclones no oceano Atlântico Norte: clima actual e cenário futuro

Mestrado em Meteorologia e Oceanografia FísicaEste trabalho estuda a actividade ciclonica verificada na regiao do Atlantico Norte no clima actual e num cenario climatico futuro. Para tal aplicou-se o algoritmo de deteccao/tracking desenvolvido pela Universidade de Melbourne a quatro conjuntos de dados diferentes: reanalises ERA40 e NCEP I (clima actual), e modelos climaticos ECHAM5 e CCSM3 (clima actual e futuro). O clima actual refere-se ao periodo entre 1971 e 2000, e o cenario climatico futuro refere-se ao periodo 2071-2100. Para o clima futuro e considerado o cenario A2 do quarto relatorio do IPCC. O estudo recai sobre uma regiao centrada no Atlantico norte sendo as fronteiras do dominio considerado definidas pelos limites: 85W - 15E, 25N - 70N. Sao apresentadas climatologias de diversas caracteristicas dos ciclones, bem como as tendencias observadas nos dois climas referidos. Faz-se, tambem, uma comparacao entre as reanalises NCEP I e ERA40. Atraves do estudo realizado para o clima actual foi possivel verificar que grande parte da actividade ciclonica centra-se nas latitudes mais elevadas do dominio. E aqui que se registam maximos de intensidade, profundidade, numero de sistemas, e minimos de pressao central. Este periodo apresenta, tambem, uma tendencia para o aumento da intensidade dos ciclones proximo da Peninsula Escandinavia e norte do Canada, verificando-se um aumento do laplaciano medio da pressao em aproximadamente 0.006 e 0.004 hPa .lat -2 ano-1 respectivamente. Apesar do elevado grau de concordancia verificado entre as reanalises NCEP I e ERA40, verificou-se que as NCEP I tendem a produzir mais sistemas nas latitudes elevadas e menos nas latitudes mais baixas durante o inverno. Os sistemas produzidos pelas reanalises NCEP I tendem, ainda, a ser de maior dimensao e menos intensos. Os modelos ECHAM5 e CCSM3 reproduzem correctamente as climatologias do periodo 1971-2000, possibilitando o seu uso paro o estudo de um clima futuro. Porem, os resultados obtidos para o clima futuro nao indicaram alteracoes substanciais ao verificado no periodo 1971-2000, com excepcao para uma ligeira reducao da intensidade dos ciclones, acompanhado de um deslocar para norte de aproximadamente 3. de latitude do maximo da media zonal de ciclones, no periodo de inverno.The goal of this work is to study the cyclonic activity in a region centered in the North Atlantic basin to the current and future climates. This has been compiled by applying the algorithm of cyclone detection/tracking developed by the University of Melbourne to four different datasets: ERA40 and NCEP I reanalysis (current climate) and two climate models: ECHAM5 and CCSM3 (current and future climate). The current climate spans the period between 1971 and 2000, while for the future climate it’s considered the period between 2071 and 2100. For the future climate the scenario A2 of the fourth IPCC report is considered. The study is performed for a region centered in the North Atlantic basin in an area covered by those limits: 85W - 15E, 25N - 70N. Climatology and trends are presented for various characteristics of cyclones in these two climates. An comparison between NCEP I and ERA40 reanalysis it’s done as well. The results for the current climate shows that much of the cyclonic activity is centered in the higher latitudes of the domain. Here we have the maximum intensity, depth, number of systems, and minimum central pressure. An increased intensity of cyclones could be observed along the Peninsula Scandinavia and northern of Canada by the increase of the mean laplacian of pressure about 0.006 and 0.004 ⁰ hPa lat -2 yr-1 respectively. Although the high degree of agreement found between the NCEP I and ERA40 reanalysis, it was found that the NCEP I tend to produce more systems in the higher latitudes and less in lower latitudes during the winter. The systems produced by the NCEP I reanalysis tend also to be larger and less intense. The ECHAM5 and CCSM3 models were capable of reproducing the climatology of the period 1971-2000, allowing its use to study a future climate. However, no substantial changes were found in the cyclonic activity of the future climate, by comparing with present climate. Nevertheless a slight reduction in the intensity of cyclones, accompanied by northward move during the winter in about 3 ⁰ latitude of maximum zonal mean of number of cyclones could be observed

Da vitimização infantil ao desvio e delinquência juvenil: estudo exploratório com a aplicação do instrumento ISRD-2

Dissertação de mestrado integrado em Psicologia (área de especialização em Psicologia da Justiça)Neste estudo pretendeu-se caraterizar a delinquência juvenil em três grupos distintos de jovens: um grupo considerado normativo (jovens sem processo na CPCJ e sem experiências de institucionalização; n=20), um grupo de risco (jovens sinalizados pela CPCJ; n=10) e um grupo em acolhimento institucional (n=27). Objetivava-se, também, averiguar a influência que a vitimização infantil tem na delinquência juvenil. Para tal recorreu-se à aplicação do questionário International Self Report Delinquency-2, tendo sido os dados posteriormente analisados no programa IBM SPSS Statistics 20. Os resultados demonstraram que o grupo em acolhimento institucional evidencia maior número de comportamentos desviantes, por jovem, (M=3.27) comparativamente com o grupo de risco e o grupo normativo (M=3.00 e M=2.05, respetivamente). Verificou-se, também, que os consumos de álcool e o download ilegal de músicas e filmes são os comportamentos desviantes mais usuais nos jovens, tendendo a iniciar-se muito precocemente. Relativamente à vitimização infantil, jovens que revelaram experiências de maus-tratos evidenciaram maior propensão para a manifestação de determinados comportamentos (consumos de álcool, danificação de bens materiais, furtos, posse de objetos perigosos, envolvimento em brigas de grupo e venda de drogas). São apresentadas as limitações da presente investigação, bem como possíveis orientações futuras no que concerne ao estudo desta problemática.In this study it was intended to characterize juvenile delinquency in three distinct groups of adolescents: A group considered normative (adolescents without CPCJ process and without experiences of institutionalization, n=20), a risk group (adolescents flagged by CPCJ, n= 10) group in institutional care (n=27). It was also aimed to investigate the influence that child victimization has on juvenile delinquency. To this end we resorted to the questionnaire International Self-Report Delinquency-2 and data was later analyzed in the IBM SPSS Statistics 20. The results showed that the group in institutional care demonstrates greater number of deviant behavior (M=3.27), per adolescent, compared to the risk group and the normative group (M=3.00 and M=2.05, respectively). It was also found that the consumption of alcohol and illegal downloading of music and movies are the most common deviant behavior, tending to start very early. With regard to child victimization, youth who revealed experiences of abuse showed greater propensity for expression of certain behaviors (alcohol consumption, damage of material goods, theft, possession of dangerous objects, involvement in group fights and selling drugs). There are presented the limitations of this research as well as possible future directions in relation to the study of this problematic

Existing technology and the one that is being used by insurance companies in the Iberian Peninsula A Gap Analysis

Dissertation presented as the partial requirement for obtaining a Master's degree in Information Management, specialization in Information Systems and Technologies ManagementThis Master’s Thesis dissertation focuses on the insurance sector, more precisely on the insurance companies present in the Iberian Peninsula and how new technologies are being used. New technology trends, digital transformation, and technology disruption are widely used terms nowadays; however, while it is quite common to use these terms, their practices and theories are not always applied by businesses. Several factors can be the cause of the failure to implement technological trends in insurance companies, either due to lack of expertise, high costs, or simply because the technologies are not mature enough and there is some fear of creating a bad reputation with customers. In order to investigate this gap between the existing technology and the technology that is being used by the insurance companies, a case study analysis was performed. Based on the technologies identified in the literature review, in-depth interviews were conducted with CIO’s, CTO’s, IT Directors, and Heads of IT of some insurance companies (from small insurance companies to market-leading insurance companies) and the results were analyzed in order to reach a valid conclusion about this gap and why it exists. After carrying out the case analysis and analyzing the answers given by the respondents, it is possible to identify that the technological gap exists and what the main reasons are for the lack of usage of the new technological trends in most insurance companies