Impacto do uso da internet e redes sociais na saúde mental

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2020Introdução: A utilização da internet generalizou-se na última década. Este meio traz inúmeras vantagens, mas têm sido reconhecidos padrões de uso que podem ter consequências na saúde mental dos utilizadores. O objectivo do presente trabalho é sintetizar a evidência disponível acerca desta relação. Métodos: Realizou-se uma pesquisa nas bases de dados PubMed e BioMedCentral por artigos originais que investigassem esta relação, com enfoque em estudos longitudinais, excluindo protocolos e estudos transversais. Resultados: Foram seleccionados 14 artigos. A maioria dos estudos incidiu sobre a faixa etária dos adolescentes e adultos jovens. Verificaram-se associações significativas entre determinados padrões de uso da internet e a diminuição da saúde mental ou bem-estar. Algumas destas relações eram mediadas por factores como a diminuição de horas de sono ou a exposição a cyberbullying. Quase todos os estudos avaliaram variáveis por meio de escalas auto-reportadas, constituindo uma limitação significativa da evidência obtida. Conclusão: O uso excessivo ou problemático da internet tem correlações positivas com sintomatologia e patologia psiquiátrica. Não é possível estabelecer com a evidência actualmente disponível uma relação de causalidade entre o uso da internet e possíveis efeitos deletérios sobre a saúde mental. Existe necessidade de realização de estudos que permitam obter evidência mais robusta acerca desta relação, assim como uma uniformização da terminologia e conceito de utilização problemática da internet.Introduction: Internet use has grown massively in the past decade. This medium carries countless possibilities, but certain patterns of use have become apparent that may have deleterious consequences on users’ mental health. The present study aims to review and synthesize the evidence currently available on this link. Methods: An online database search was conducted, via PubMed and BioMedCentral, for original studies that investigated the relationship between internet/social media use and mental health, focusing on longitudinal studies and excluding study protocols as well as cross-sectional studies. Results: 14 studies were included. The majority centered on younger populations, i.e. teenagers and young adults. Positive associations were found between certain patterns of use and poorer mental health or wellbeing. Some of these were found to be mediated by factors such as inadequate sleep or exposure to cyberbullying. Nearly all studies found included self-report measures, which constitutes an important limitation in the obtained evidence. Conclusion: Excessive or problematic internet use has positive correlations with psychiatric symptoms and pathology. It is not possible to establish a causal link between internet use and any possible negative effects on mental health, based on the current available evidence. There is a need for studies with designs capable of investigating this correlation, as well as a more precise definition of the terminology and concept of problematic internet use

Método eletroquímico para determinação direta da concentração de cloretos e uso do mesmo

Universidade Federal do Rio Grande do SulEngenhariaDepositad

Immunoreactive pattern of Staphylococcus epidermidis biofilm against human whole saliva

Saliva is essential to interact with microorganisms in the oral cavity. Therefore, the interest in saliva antimicrobial properties is on the rise. Here, we used an immunoproteomic approach, based on protein separation of Staphylococcus epidermidis biofilms by 2DE, followed by Western-blotting, to compare human serum and saliva reactivity profile. A total of 17 proteins were identified by MALDI-TOF/TOF. Serum and saliva presented a distinct pattern of immunoreactive proteins. Our results suggest that saliva seems to have higher propensity to react against S. epidermidis proteins with oxidoreductase activity and proteins involved with L-serine metabolic processes. We show that saliva was a powerful tool for the identification of potential S. epidermidis biofilms proteins.V.C. had an individual FCT fellowship (SFRH/BD/78235/2011). N.C. is an Investigator FCT. This work was funded by Fundacao para a Ciencia e a Tecnologia (FCT) and COMPETE grants PTDC/BIA-MIC/113450/2009, FCOMP-01-0124-FEDER-014309, QOPNA research unit (project PEst-C/QUI/UI0062/2013), RNEM (National Mass Spetrometry Network), and CENTRO-07-ST24-FEDER-002034. The authors also thank the FCT Strategic Project PEst-OE/EQB/LA0023/2013 and the Project "BioHealth - Biotechnology and Bioengineering approaches to improve health quality", Ref. NORTE-07-0124-FEDER-000027, co-funded by the Programa Operacional Regional do Norte (ON.2 - O Novo Norte), QREN, FEDER. The authors also acknowledge the project "Consolidating Research Expertise and Resources on Cellular and Molecular Biotechnology at CEB/IBB", Ref. FCOMP-01-0124-FEDER-027462

Lipidomics reveals similar changes in serum phospholipid signatures of overweight and obese pediatric subjects

Obesity is a public health problem and a risk factor for pathologies such type 2 diabetes mellitus, cardiovascular diseases, and nonalcoholic fatty liver disease. Given these clinical implications, there is a growing interest to understand the pathophysiological mechanism of obesity. Changes in lipid metabolism have been associated with obesity and obesity-related complications. However, changes in the lipid profile of obese children have been overlooked. In the present work, we analyzed the serum phospholipidome of overweight and obese children by HILIC-MS/MS and GC-MS. Using this approach, we have identified 165 lipid species belonging to the classes PC, PE, PS, PG, PI, LPC, and SM. The phospholipidome of overweight (OW) and obese (OB) children was significantly different from normal-weight children (control). Main differences were observed in the PI class that was less abundant in OW and OB children and some PS, PE, SM, and PC lipid species are upregulated in obese and overweight children. Although further studies are needed to clarify some association between phospholipid alterations and metabolic changes, our results highlight the alteration that occurs in the serum phospholipid profile in obesity in children.publishe

MAMMALS IN PORTUGAL : A data set of terrestrial, volant, and marine mammal occurrences in P ortugal

Mammals are threatened worldwide, with 26% of all species being includedin the IUCN threatened categories. This overall pattern is primarily associatedwith habitat loss or degradation, and human persecution for terrestrial mam-mals, and pollution, open net fishing, climate change, and prey depletion formarine mammals. Mammals play a key role in maintaining ecosystems func-tionality and resilience, and therefore information on their distribution is cru-cial to delineate and support conservation actions. MAMMALS INPORTUGAL is a publicly available data set compiling unpublishedgeoreferenced occurrence records of 92 terrestrial, volant, and marine mam-mals in mainland Portugal and archipelagos of the Azores and Madeira thatincludes 105,026 data entries between 1873 and 2021 (72% of the data occur-ring in 2000 and 2021). The methods used to collect the data were: live obser-vations/captures (43%), sign surveys (35%), camera trapping (16%),bioacoustics surveys (4%) and radiotracking, and inquiries that represent lessthan 1% of the records. The data set includes 13 types of records: (1) burrowsjsoil moundsjtunnel, (2) capture, (3) colony, (4) dead animaljhairjskullsjjaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8),observation in shelters, (9) photo trappingjvideo, (10) predators dietjpelletsjpine cones/nuts, (11) scatjtrackjditch, (12) telemetry and (13) vocalizationjecholocation. The spatial uncertainty of most records ranges between 0 and100 m (76%). Rodentia (n=31,573) has the highest number of records followedby Chiroptera (n=18,857), Carnivora (n=18,594), Lagomorpha (n=17,496),Cetartiodactyla (n=11,568) and Eulipotyphla (n=7008). The data setincludes records of species classified by the IUCN as threatened(e.g.,Oryctolagus cuniculus[n=12,159],Monachus monachus[n=1,512],andLynx pardinus[n=197]). We believe that this data set may stimulate thepublication of other European countries data sets that would certainly contrib-ute to ecology and conservation-related research, and therefore assisting onthe development of more accurate and tailored conservation managementstrategies for each species. There are no copyright restrictions; please cite thisdata paper when the data are used in publications.info:eu-repo/semantics/publishedVersio

Mammals in Portugal: a data set of terrestrial, volant, and marine mammal occurrences in Portugal

Mammals are threatened worldwide, with ~26% of all species being included in the IUCN threatened categories. This overall pattern is primarily associated with habitat loss or degradation, and human persecution for terrestrial mammals, and pollution, open net fishing, climate change, and prey depletion for marine mammals. Mammals play a key role in maintaining ecosystems functionality and resilience, and therefore information on their distribution is crucial to delineate and support conservation actions. MAMMALS IN PORTUGAL is a publicly available data set compiling unpublished georeferenced occurrence records of 92 terrestrial, volant, and marine mammals in mainland Portugal and archipelagos of the Azores and Madeira that includes 105,026 data entries between 1873 and 2021 (72% of the data occurring in 2000 and 2021). The methods used to collect the data were: live observations/captures (43%), sign surveys (35%), camera trapping (16%), bioacoustics surveys (4%) and radiotracking, and inquiries that represent less than 1% of the records. The data set includes 13 types of records: (1) burrows | soil mounds | tunnel, (2) capture, (3) colony, (4) dead animal | hair | skulls | jaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8), observation in shelters, (9) photo trapping | video, (10) predators diet | pellets | pine cones/nuts, (11) scat | track | ditch, (12) telemetry and (13) vocalization | echolocation. The spatial uncertainty of most records ranges between 0 and 100 m (76%). Rodentia (n =31,573) has the highest number of records followed by Chiroptera (n = 18,857), Carnivora (n = 18,594), Lagomorpha (n = 17,496), Cetartiodactyla (n = 11,568) and Eulipotyphla (n = 7008). The data set includes records of species classified by the IUCN as threatened (e.g., Oryctolagus cuniculus [n = 12,159], Monachus monachus [n = 1,512], and Lynx pardinus [n = 197]). We believe that this data set may stimulate the publication of other European countries data sets that would certainly contribute to ecology and conservation-related research, and therefore assisting on the development of more accurate and tailored conservation management strategies for each species. There are no copyright restrictions; please cite this data paper when the data are used in publications

Benchmarking de Infraestruturas de Virtualização para a Cloud

Dissertação de Mestrado em Engenharia Informática apresentada à Faculdade de Ciências e Tecnologia da Universidade de CoimbraCloud computing has witnessed a tantalizing growth in recent years, with more and more companies migrating their previously in-house sys- tems to the Cloud, and Cloud Providers racing to match this growth by building newer and bigger datacenters. Nonetheless, this migration is still seen with dubious eyes by some companies, rightfully reticent in con d- ing their systems to external entities, over whom they possess little to no control. One of the reasons of this distrust has to do with the resilience of their systems. This dilemma set the foundation for this thesis. Our work sets the foundation for the development of a resilience benchmark for Cloud Computing systems, presents a watchdog mechanism capable of detecting problems and recovering the service of virtualized cloud systems and reports the results of various campaigns. The most important asset produced from this thesis are the 3 Fault Injection tools that we developed and from now on can support future research projects

Evaluating and improving cloud computing dependability

Tese no âmbito do Programa de Doutoramento em Ciências e Tecnologias da Informação orientada pelo Professor Doutor Raul André Brajczewski Barbosa e pelo Professor Doutor Henrique Santos do Carmo Madeira e apresentada ao Departamento de Engenharia Informática da Faculdade de Ciências e Tecnologia da Universidade de Coimbra.Cloud computing has become the preferred choice by the large majority of organizations to obtain computing resources. Despite the various advantages of cloud computing, it has experienced difficulty in finding adoption by organizations that have mission-critical workloads with strict dependability requirements, as it is at a disadvantage when compared to dedicated infrastructures due to its own ethos. Cloud computing consists in the sharing of computing resources through a network to multiple clients that use the same hosted infrastructure. Resource sharing is usually accomplished using virtualization, however both the practice of sharing the same physical resources and the usage of virtualization increase the impact that a failure may have and the likelihood of failure occurrence. If cloud computing is to be regarded as a trusted platform to support mission-critical workloads, then it must provide similar levels of dependability as those attained by dedicated infrastructures. This thesis addresses the aforementioned issue through the evaluation of the current state of cloud computing dependability and the proposal of contributions that increase its dependability. Both actions are interlinked, since the design of fault tolerance mechanisms that can balance fault coverage and performance overhead requires detailed knowledge about the manner in which cloud computing fails. This information can be extracted from realistic failure data, which is obtained in this thesis using an experimental methodology that employs fault injection for accelerating the data collection process. To support the experimental campaigns, the ucXception framework and the fault injection tools associated with it have been developed from the ground up as part of this thesis. Before the ucXception framework, various fault injection tools had been developed, but few were capable of being used in the context of cloud computing and virtualization, as well as supporting fault models representative of transient hardware faults and software faults. The experimental campaigns yield new findings, from which we highlight the observation that faults in the hypervisor and privileged virtual machine can cause common-mode failures that affect multiple clients at once, and, in some cases, lead to silent data corruption. Faults during the execution of guest virtual machines largely cause failures that lead to downtime of the applications in the virtual machine and which cannot propagate to other virtual machines or to the hypervisor, thus suggesting that mature virtualization solutions provide good isolation. Using this knowledge, we create Romulus, a fault tolerance technique that can tolerate hypervisor failures by migrating virtual machines from the failed hypervisor to a co-located hypervisor. Romulus provides coverage of software and transient hardware faults without requiring redundant hardware and with low downtime, which contributes to its goal of increasing the availability of cloud computing infrastructure. A proof-of-concept implementation is developed and evaluated using fault injection, thereby showing that it can often recover at least part of the virtual machines in a system after a failure. Furthermore, we propose the Availability-as-a-Service framework for promoting the availability of cloud infrastructure at an agreeable performance cost. The framework uses nested virtualization to host a minimal microvisor that contains just the core logic and depends on modules that encompass specific mechanisms that provide fault tolerance and which can be enabled and disabled explicitly by the cloud provider and client.A computação em nuvem tornou-se na escolha predileta de uma grande maioria de organizações no momento de adquirir recursos computacionais. Apesar das múltiplas vantagens da computação em nuvem, regista-se dificuldade em que esta seja adotada em cenários nos quais existam requisitos estritos de confiabilidade. O próprio ethos da computação em nuvem coloca-a numa posição desfavorável quando comparada com uma infraestrutura dedicada. A computação em nuvem é a partilha de recursos computacionais para vários clientes através de uma rede, sendo normalmente implementada usando virtualização. Todavia tanto a prática de partilhar os mesmos recursos físicos como o uso de virtualização aumentam o impacto que uma avaria pode ter e a probabilidade da sua ocorrência. Para que a computação em nuvem possa ser considerada como uma plataforma adequada e capaz de suportar cargas de trabalho críticas, esta deve providenciar níveis de confiabilidade semelhantes aos de infraestruturas dedicadas. A tese aborda este problema através da avaliação do estado da arte da confiabilidade da computação em nuvem e da criação de propostas para aumentar a sua confiabilidade. Ambos estes aspetos estão relacionados, pois o desenho de mecanismos de tolerância a falhas capazes de obter um bom equilíbrio entre cobertura de falhas e custo de desempenho implica um conhecimento detalhado sobre os vários tipos de avarias que afetam a computação em nuvem. Por sua vez, essa informação pode ser extraída de dados de avarias realísticos, que são obtidos nesta tese com recurso a uma metodologia experimental baseada no uso de injeção de falhas para acelerar o processo de coleção de dados. Para dar suporte às campanhas experimentais, a framework ucXception e as ferramentas de injeção de falhas que lhe estão associadas foram desenvolvidas de raiz durante o decurso deste doutoramento. A framework ucXception é construída a partir de vários anos de estado da arte em ferramentas de injeção de falhas, mas adiciona suporte para modelos de falhas representativos de falhas transitórias de hardware e falhas de software, para além de ser orientada para o uso em contexto de sistemas virtualizados e de computação em nuvem. As campanhas experimentais resultaram em várias descobertas, das quais salientamos a observação de que falhas no hypervisor e na máquina virtual privilegiada podem levar a avarias que afetam vários clientes simultaneamente e com menor frequência podem potenciar a corrupção silenciosa de dados. Em regra, falhas durante a execução das máquinas virtuais hóspedes levam a avarias que causam indisponibilidade das aplicações que executam na própria máquina virtual e que não é propagada para outras máquinas virtuais ou para o hypervisor, o que sugere que soluções de virtualização maduras providenciam bom isolamento. Usando esta informação, criámos a técnica de tolerância a falhas denominada por Romulus, que é capaz de tolerar avarias do hypervisor através da migração das máquinas virtuais do hypervisor avariado para um hypervisor localizado no mesmo sistema físico. O Romulus consegue cobrir falhas de software e falhas transitórias de hardware sem necessitar de hardware redundante e obtendo um baixo tempo de inatividade, factos que contribuem para alcançar o objetivo de melhorar a disponibilidade da infraestrutura que suporta a computação em nuvem. Uma prova de conceito foi desenvolvida e avaliada através da injeção de falhas, assim demonstrando que frequentemente é possível recuperar parte das máquinas virtuais do sistema após avaria. Para além disso, propusemos a framework Availability-as-a-Service, cujo objetivo é melhorar a disponibilidade da infraestrutura de computação em nuvem sem um custo de performance exagerado. A framework usa virtualização nested para alojar um pequeno microvisor que trata apenas da lógica essencial e que depende de módulos que implementam mecanismos de tolerância a falhas e que podem ser ligados e desligados explicitamente pelos provedores e clientes da computação em nuvem

Mitigating Virtualization Failures Through Migration to a Co-Located Hypervisor

Many organizations are moving their systems to the cloud, where providers consolidate multiple clients using virtualization, which creates challenges to business-critical applications. Research has shown that hypervisors fail, often causing common-mode failures that may abruptly disrupt dozens of virtual machines simultaneously. We hypothesize and empirically show that a significant percentage of virtual machines affected by a hypervisor failure are capable of continuing execution on a new hypervisor. Supported by this observation, we design a technique for recovering from hypervisor failures through efficient virtual machine migration to a co-located hypervisor, which allows virtual machines to continue executing with minimal downtime and which can be transparently applied to existing applications. We evaluate a proofof-concept implementation using fault injection of hardware and software faults and show that it can recover, on average, 41-46% of all virtual machines, as well as having a mean virtual machine downtime of 3 second

An immunoproteomic approach for characterization of dormancy within Staphylococcus epidermidis biofilms

Virulence of Staphylococcus epidermidis is mainly attributed to surface colonization and biofilm formation in indwelling medical devices. Physiological heterogeneity of biofilms may influence host immune response and sensitivity to antibiotics. Dormant cells, among others, contribute to biofilm heterogeneity. The aim of this study was to identify immunogenic proteins of S. epidermidis biofilms associated with dormancy mechanism, by using two-dimensional electrophoresis (2-DE) immunoblotting and mass spectrometry (MS). A total of 19 bacterial proteins, recognized by human serum samples, were identified. These proteins were mainly involved in small molecule metabolic biological processes. Catalytic activity and ion binding were the most representative molecular functions. CodY and GpmA proteins were more reactive to sera when biofilm dormancy was induced, while FtnA and ClpP were more reactive when dormancy was prevented. This is the first work that identifies differences in immunoreactive proteins within bacterial biofilms with induced or prevented dormancy. Considering the importance of dormancy within biofilms, further evaluation of these proteins can provide insights into the mechanisms related to dormancy and help to improve current understanding on how dormancy affects the host immune response.VC had an individual FCT fellowship (SFRH/BD/78235/2011). NC is an Investigator FCT. This work was funded by Fundacao para a Ciencia e a Tecnologia (FCT) and COMPETE grants PTDC/BIA-MIC/113450/2009, FCOMP-01-0124-FEDER-014309, QOPNA research unit (project PEst-C/QUI/UI0062/2013), RNEM (National Mass Spetrometry Network) and CENTRO-07-ST24-FEDER-002034. The authors also thank the FCT Strategic Project PEst-OE/EQB/LA0023/2013 and the Project "BioHealth - Biotechnology and Bioengineering approaches to improve health quality", Ref. NORTE-07-0124-FEDER-000027, co-funded by the Programa Operacional Regional do Norte (ON.2 - 0 Novo Norte), QREN, FEDER. The authors also acknowledge the project "Consolidating Research Expertise and Resources on Cellular and Molecular Biotechnology at CEB/IBB", Ref. FCOMP-01-0124-FEDER-027462