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This review discusses the fate of antimicrobial resistance and virulence genes frequently present among microbiomes. A central concept in epidemiology is the mean number of hosts colonized by one infected host in a population of susceptible hosts: R0. It characterizes the disease’s epidemic potential because the pathogen continues its propagation through susceptible hosts if it is above one. R0 is proportional to the average duration of infections, but non-pathogenic microorganisms do not cause host death, and hosts do not need to be rid of them. Therefore, commensal bacteria may colonize hosts for prolonged periods, including those harboring drug resistance or even a few virulence genes. Thus, their R0 is likely to be (much) greater than one, with peculiar consequences for the spread of virulence and resistance genes. For example, computer models that simulate the spread of these genes have shown that their diversities should correlate positively throughout microbiomes. Bioinformatics analysis with real data corroborates this expectation. Those simulations also anticipate that, contrary to the common wisdom, human’s microbiomes with a higher diversity of both gene types are the ones that took antibiotics longer ago rather than recently. Here, we discuss the mechanisms and robustness behind these predictions and other public health consequences.

Bacterial cells often suffer a fitness cost after conjugative plasmids’ entry because these cells replicate slower than plasmid-free cells. Compensatory mutations may appear after tens of or a few hundred generations, reducing or eliminating this cost. A previous work based on a mathematical model and computer simulations has shown that plasmid-bearing cells already adapted to the plasmid may gain a fitness advantage when plasmids transfer into neighboring plasmid-free cells because these cells are still unadapted to the plasmid. These slow-growing transconjugants use fewer resources, which can benefit donor cells. However, opportunities for compensatory mutations in transconjugants increase if these cells become numerous (through replication or conjugation). Moreover, transconjugants also gain an advantage when transferring the plasmid, but the original donors may be too distant from conjugation events to gain an advantage. To understand which consequence prevails, we performed further computer simulations allowing versus banning transfer from transconjugants. The advantage to donors is higher if transconjugants do not transfer plasmids, mainly when donors are rare and when the plasmid transfer rate (from donors) is high. These results show that conjugative plasmids are efficient biological weapons even if the transconjugant cells are poor plasmid donors. After some time, conjugative plasmids gain other host-benefit genes, such as virulence and drug-resistance.

Conjugative plasmids often carry virulence and antibiotic-resistant genes. Therefore, understanding the behavior of these extra-chromosomal DNA elements gives insights into their spread. Bacteria frequently replicate slower after plasmids’ entry, an observation inconsistent with the plasmids’ ubiquity in nature. Several hypotheses explain the maintenance of plasmids among bacterial communities. However, the numerous combinations of bacterial species and strains, plasmids, and environments claim a robust elucidatory mechanism of plasmid maintenance. Previous works have shown that donor cells already adapted to the plasmid may use the plasmid as a ‘weapon’ to compete with non-adapted plasmid-free cells. Computer simulations corroborated this hypothesis with a wide range of parameters. Here we show that donor cells benefit from harboring conjugative plasmids even if compensatory mutations in transconjugant cells occur in the plasmid, not on chromosomes. The advantage’s leading causes are as follows: mutations take time to appear, many plasmids remain costly, and re-transfer of mutated plasmids usually occurs in sites distant to the original donors, implying little competition between these cells. Research in previous decades cautioned against uncritical acceptance of the hypothesis that resistance cost helps to preserve antibiotics’ effectiveness. This work gives a new twist to this conclusion by showing that costs help antibiotic-resistant bacteria to compete with plasmid-free cells even if compensatory mutations appear in plasmids.

Integrada no âmbito da dinamização do Ano Europeu da Criatividade e Inovação e partindo do pressuposto central de que a aprendizagem é um factor determinante para o desenvolvimento das pessoas e das organizações em que estão inseridas e, indirectamente, para o desenvolvimento da sociedade em geral, a conferência Creative Learning Innovation Marketplace teve como principal mérito o facto de permitir fazer um ponto de situação, nomeadamente, sobre os avanços da utilização das tecnologias de informação e comunicação (TIC) para fins educativos e formativos. Ofereceu ainda uma panorâmica alargada e consubstanciada dos desafios com que as organizações terão de se confrontar para tirarem partido do potencial criativo das TIC para a aprendizagem e, consequentemente, para a criação de ambientes favoráveis à inovação, mudança e desenvolvimento.

Bridges play a crucial role in modern societies, regardless of their culture, geographical location, or economic development. The safest, most economical, and most resilient bridges are those that are well managed and maintained. Recently, climate change has been posed as one of the greatest concerns for the health of bridges. Although the uncertainty associated with the magnitude of the change is large, the fact that our climate is changing is unequivocal. As a result, making bridges resilient to climate change is a priority for the authorities. A well-planned early intervention may save lives and money. Until now, the focus of scientific research has mostly been on the climate science, but any practical plan for the adaptation of bridges has to be rooted in other disciplines, including physics, chemistry, engineering, economics, and finance. Therefore, the goal of this paper is to review the work already done from climate change to bridges and set a roadmap for an integrated assessment approach to the adaptation of bridges to climate change. This approach is grounded in a probabilistic- and physics-based framework able to prioritize bridge adaptation measures as a function of bridge location, climate scenario, impact, vulnerability, risk, and cost in order to assist the authorities in the decision-making process. Because adaptation to climate change is highly context-specific, this approach is mainly focused on concrete bridges. Structural health monitoring technology is proposed as a mechanism for assessing and continuously evaluating the structural condition of bridges and for triggering adaptation measures as a function of the predicted severity of climate change.

In Mediterranean catchments, such as the Sorraia catchment in Portugal, it is expected that climate change will increase drought stress and the deterioration of water quality in reservoirs. Sustainable land management (SLM) practices are seen as an adaption measure for those problems, but the effectiveness on improving climate change impacted water availability and quality on catchment scale is still poorly understood. Therefore, this study aims to evaluate the effectiveness of SLM practices in adapting the impacts of climate change on water availability and quality of the Montargil and Maranhão reservoirs in the Sorraia catchment. A well-calibrated Soil Water Assessment Tool model is used to simulate four scenarios (2041–2071 and 2071–2100; representative climate pathways 4.5 and 8.5), to investigate the effects of climate change on total phosphorus load (TP) in streams, reservoir volume, irrigation use and water exploitation index (WEI). Results showed that WEI will not exceed any water stress level while reservoir water quality will worsen. In particular since the TP load in streams flowing into the reservoirs increases and the volume decreases, it is likely that the existing P limitation for eutrophication will be counteracted. Nevertheless, tested SLM practices were able to decrease the TP load in those streams and increase the reservoir volume under future climates. Overall, this study shows that the SLM practices are effective in adapting to the climate change effects regarding reservoir water quality, without worsening the water availability; thus, it is a promising tool that should be investigated further for application by e.g. local land-users and decision makers.

Antimicrobial resistance is presently one of the greatest threats to public health. The excessive and indiscriminate use of antibiotics imposes a continuous selective pressure that triggers the emergence of multi-drug resistance. We performed a large-scale analysis of closed bacterial genomes to identify multi-drug resistance considering the ResFinder antimicrobial classes. We found that more than 95% of the genomes harbor genes associated with resistance to disinfectants, glycopeptides, macrolides, and tetracyclines. On average, each genome encodes resistance to more than nine different classes of antimicrobial drugs. We found higher-than-expected co-occurrences of resistance genes in both plasmids and chromosomes for several classes of antibiotic resistance, including classes categorized as critical according to the World Health Organization (WHO). As a result of antibiotic-resistant priority pathogens, higher-than-expected co-occurrences appear in plasmids, increasing the potential for resistance dissemination. For the first time, co-occurrences of antibiotic resistance have been investigated for priority pathogens as defined by the WHO. For critically important pathogens, co-occurrences appear in plasmids, not in chromosomes, suggesting that the resistances may be epidemic and probably recent. These results hint at the need for new approaches to treating infections caused by critically important bacteria.

Several studies have investigated the relationship between scientists and journalists. However, Southern Europe has been less studied when it comes to understanding the nature and effectiveness of collaborations between these two groups of professionals. To address this gap, this study focused on researchers (i.e., academics and scientists from different fields, including clinical researchers and medical doctors) who conducted research activities on COVID-19-related topics in three Southern European countries (Italy, Portugal, and Spain). Using an approach that combined survey data (n = 317) with semi-structured interviews (n = 40), we explored researchers’ personal beliefs, opinions, and experiences regarding their encounters with the media during the pandemic. Our results show that researchers’ motivations, concerns, and benefits in their interactions with the media remained largely unchanged during the pandemic. Despite the additional challenges posed by the health emergency, most researchers in Italy, Portugal, and Spain rated their interactions with journalists positively. Several practices to promote and maintain trustful and fruitful cooperation with journalists were also identified. Additionally, lessons learned were extracted from the interactions between researchers and journalists during the pandemic. They hold particular relevance in a context of uncertainty, fake news, high demand for information and high expectations in science and technology. These findings aim to support both the scientific community and media professionals to deal with current and future communicative challenges such as health, environmental and social crises that require joint efforts from multiple societal actors.

Plants continue to constitute key elements of medical practice in West African countries. The Cabo Verde archipelago hosts a great diversity of medicinal plants and local markets are considered important sites for trading plants harvested by rural communities. This study has two main goals: (i) to assess the medicinal uses of native species in Santiago, the biggest island of the archipelago, and (ii) to evaluate the antioxidant, antimicrobial and antidiabetic/antihyperglycemic activities of two native trees (Tamarix senegalensis and Sideroxylon marginatum) used in traditional medicine and traded in local markets. Our results revealed that on Santiago Island, 24 native plants are used in traditional medicine. The main uses of these species (e.g., forage, timber, food and fibres), their medicinal applications, the plant parts used, their mode of administration and conservation status are presented here for the first time. Moreover, the pharmacological characterization of two native tree species revealed that hydroethanolic extracts were richer in phenolic compounds and more active than their aqueous counterparts. All the studied extracts revealed significant antioxidant properties (DPPH and FRAP assays) and were generally moderately active against Gram-positive bacteria. All the extracts inhibited the activities of the carbohydrate digestive enzymes α-glucosidase and α-amylase in a dose-dependent manner. For α-glucosidase, the detected inhibitory activity (IC50 values from 2.0 ± 0.2 μg/mL to 9.9 ± 1.2 μg/mL) was significantly higher than that of acarbose, suggesting that extracts of both species can delay glucose absorption, thereby assisting in slowing down the progression of diabetes. Our findings highlight the crucial importance that medicinal plants have for the Cabo Verdean population, while also raising awareness on the need for sustainable use and conservation of native flora, and of tree species traded in local markets in particular.

Background. Cashew (Anacardium occidentale L.) is a crop currently grown in several tropical countries because of the economic importance of cashew nuts. Despite its enormous economic worth, limited research has been conducted on the molecular diversity of cashew genetic resources. In this study, a wide comprehensive assessment of the genetic diversity of cashew trees in East Timor was performed using microsatellites (SSRs) to evaluate intraspecific diversity and population structuring. Methods. A total of 207 individual cashew trees, including trees from East Timor (11), and outgroup populations from Indonesia (one) and Mozambique (two), were analyzed with 16 cashew-specific SSRs. A comprehensive sampling of cashew trees within East Timor was performed, covering the distribution of cashew orchards in the country. Genetic diversity indices were calculated, and population structuring was determined using three different approaches: genetic distances (UPGMA and NJ), AMOVA, and individual-based clustering methods through Bayesian (STRUCTURE) and multivariate (DAPC) analyses. Results. The population structuring analysis revealed that the genetic diversity of cashew populations in East Timor was higher in this study than previously reported for cashew trees. A higher allelic richness was found within cashew populations in East Timor compared with the outgroup populations (Mozambique and Indonesia), reinforced by the presence of private alleles. Moreover, our study showed that cashew populations in East Timor are grouped into two dissimilar genetic groups, which may suggest multiple cashew introductions over time. These new cashew genetic resources could be explored for future crop improvement. Conclusions. Crop diversity underpins the productivity, resilience, and adaptive capacity of agriculture. Therefore, this study provides useful information regarding genetic diversity and population structure that can be harnessed to improve cashew production in East Timor. This data is also important to creating a country-specific genetic cashew signature to increase cashew market value.

In this thesis, we investigate the possibility of gravitationally generated particle production in modified gravity. To accomplish this objective, we consider the equivalent scalar-tensor representation of f(R,T) gravity, a modified theory of gravity in which the matter energy-momentum tensor may not be conserved due to a non-minimal curvature-matter coupling. By recurring to the formalism of irreversible thermodynamics of open systems, such non-conservation can be interpreted as an irreversible flow of energy from the gravitational sector to the matter sector, which, in particular, could result in particle creation. Hence, we explore the physical and cosmological consequences of this feature by using the referred formalism. Subsequently, we obtain and discuss the expressions for the particle creation rate, the creation pressure, and the entropy and temperature evolutions. Applied together with the modified field equations of scalar-tensor f(R,T) gravity, the thermodynamics of open systems lead to a generalization of the standard ΛCDM cosmological paradigm, in which the particle creation rate and pressure are considered effectively as components of the cosmological fluid energy-momentum tensor. Furthermore, we also consider specific functional models and compare the scalar-tensor f(R,T) cosmology with the ΛCDM scenario and the observational data for the Hubble function. The properties of the particle creation rate through gravitational matter production are further investigated in both the low and high redshift limits.

Esta Newsletter (NL) resulta de uma parceria entre o Instituto de Saúde Baseada na Evidência e a Cochrane Portugal, e tem como objectivo disponibilizar informação sobre áreas importantes para a prática clínica, com base na melhor evidência científica disponível. São incluídos estudos relevantes, criticamente avaliados pela sua validade, importância dos resultados e aplicabilidade prática, resumidos numa óptica de suporte à decisão. É dada prioridade a estudos de causalidade incluindo-se ainda, quando justificado, estudos qualitativos e metodológicos, assim como revisões científicas. O conteúdo da NL é da exclusiva responsabilidade do(s) seu(s) autor(es).

last chance tourism, which can be described as the practice of tour-ism in environmentally damaged or threatened spaces, is an emerg-ing trend that has been considered problematic due to the pressure that it places on already fragile environments. this article explores the possibilities of turning last chance tourism experiences into hope-ful tourism experiences, by creating emotionally driven last chance tourism experiences in controlled and safe environments through digital storytelling. We draw on literature on transformative, hopeful and flourishing tourism to argue that last chance experiences provide unique opportunities for eliciting reflection among tourists and pro-mote a greater environmental awareness if they are driven by emo-tionally engaging narratives. Our study explores the outcomes of an experiment conducted at the ajuda Botanical Garden (lisbon, Portugal) with a futuristic mixed-reality game that places users as members of a scientific expedition looking for plants that have become extinct in the twenty-second century. the results of this study show how the game’s last chance narrative generated contra-dictory, mixed feelings among the participants, which ultimately led to hopeful existential reflection about nature conservation action. With this in mind, we reflect on the potential of transformative last chance tourism experiences guided by digital narratives.

O I Ciclo de Conferências Porto de Mós: Tempo, Espaço e Memória trouxe ao concelho de Porto de Mós académicos especialistas de diferentes áreas com conhecimento produzido sobre o concelho, promovendo um debate aberto e informado sobre os espaços e equipamentos locais na esperança de contribuir para um pensamento e usufruto pleno destes.

O que implica a relação subjacente ao título do painel O Digital e o Currículo, que tivemos a honra de organizar e moderar no âmbito da VI Conferência Internacional de TIC na Educação (Challenges 2009), isto é, a relação entre os objectivos de natureza curricular perseguidos pela Escola e o potencial que as tecnologias digitais têm para oferecer, foi a questão de fundo que tivemos oportunidade de sugerir como base da reflexão e discussão. O que significa, em particular, essa relação, numa altura em que é tão saliente a força das imagens e cada vez mais questionada a perenidade do conhecimento científico? Que mudanças do ponto de vista metodológico terão de verificar‐se nos processos de ensinar e de aprender? Que competências deverão ter professores e educadores? Como poderão os recursos digitais ajudar a resolver os problemas colocados pela aprendizagem? Estas, algumas das interrogações cuja resposta poderá ajudar a fazer luz sobre a problemática mais ampla da utilização das tecnologias digitais em contexto educativo.

Research suggests that for stroke patients, high-intensity training is critical for patient recovery. This can be provided by robotic rehabilitation in combination with virtual reality (VR), enabling highly intensive and motivating exercises. The more motivated the patients are, the more engaged they will be in performing the exercises, ultimately leading to better motor function improvement. However, in conventional therapy and most research, the robot is usually not visualized, which can lead to a discrepancy between what the user sees and feels. In this work, we present the development of a digital twin of an upper limb rehabilitation exoskeleton in VR. The user interacted with the virtual environment (VE) through a head-mounted display and manipulation of the real robot. To create a more functional and realistic interaction with the VE, the exoskeleton was previously upgraded with one more degree of freedom, by integrating a novel hand module, allowing the user to perform grasping movements. In addition, a prototype of a VR game aimed at the interaction between the digital twin and the VE was developed, as well as preliminary measurements of the kinematic accuracy of the digital twin and its kinematic model. When the user moved the rehabilitation robot, the digital twin was found to move accordingly, mimicking the movements of all joints. With only a small position offset, it can be concluded that despite the exoskeleton’s complexity, the implementation was successful, and this offset will probably not reduce the immersion or embodiment of the user. The developed visualization enables the possibility of studying the influence of digital twins on motor learning. Although future work is needed, namely adjusting the joints of the digital twin, and testing the visualization model on real patients, this study should be considered as a starting point to allow the development of more effective rehabilitation exercises.

Este estudo incide sobre o desenvolvimento profissional de professores do 1º ciclo do ensino básico nas dimensões reflexão, práticas e conhecimento didáctico, colaboração e autonomia, no contexto de um projecto de investigação colaborativa que toma como ponto de partida as práticas comunicativas. O enquadramento teórico está organizado em quatro áreas fundamentais: conhecimento e reflexão, autonomia e colaboração, desenvolvimento profissional e formação, e comunicação matemática. Sublinha-se a ideia do desenvolvimento profissional de professores como um processo de natureza dinâmica, ao longo da vida, em que intervém uma multiplicidade de elementos. Além disso, encara-se a investigação dos professores sobre as suas práticas, em contextos colaborativos, como uma forte possibilidade deles se desenvolverem profissionalmente. Dada a natureza do objecto de estudo e a concepção de conhecimento adoptada, a metodologia da investigação segue o paradigma qualitativo de cunho interpretativo, apoiada em estudos de caso. Ao longo de quase dois anos, os três professores do estudo participaram num projecto colaborativo, reflectindo e investigando as suas práticas comunicativas de Matemática nas aulas do 1º ciclo. De forma a compreender o seu desenvolvimento profissional neste contexto, recolheram-se dados através da observação de aulas e sessões do projecto, entrevistas individuais aos professores, diários, notas de campo e documentos escritos. A análise de dados acompanhou a recolha, permitindo durante o decorrer do projecto a identificação de tensões, problemas e questões que se mostraram fundamentais ao progresso do estudo. No final, após a recolha de dados, a análise de conteúdo, permitiu a des-construção e re-construção da informação, tendo em vista responder às questões formuladas. Os resultados deste estudo mostram que os professores, no contexto do projecto de investigação de natureza colaborativa, desenvolveram-se profissionalmente numa variedade de dimensões. Este desenvolvimento assentou em três dimensões fundamentais: práticas comunicativas, conhecimento didáctico e reflexão. O progresso nestas três dimensões ocorreu de forma dinâmica e interactiva, tendo impacto favorável no desenvolvimento das suas capacidades de colaboração e autonomia. Este processo foi significativamente diferente do que poderia ter sido alcançado em ambientes formativos mais estruturados ou através da simples reflexão sobre a sua prática. Assim, os participantes desenvolveram, de forma integrada, o seu conhecimento didáctico da Matemática e as suas práticas comunicativas. Na evolução do conhecimento didáctico dos professores do 1º ciclo, dois domínios assumiram particular importância: o conhecimento da Matemática e o conhecimento dos processos de aprendizagem e neste, em particular, a comunicação matemática. O conhecimento da Matemática funcionou, nuns casos, como elemento limitador e, noutros, como elemento possibilitador do desenvolvimento profissional dos professores. O conhecimento da Matemática surgiu como condição necessária, mas não suficiente, para o desenvolvimento do conhecimento didáctico dos professores do 1° ciclo, ganhando com a articulação com os outros domínios, como os processos de aprendizagem, o currículo e a instrução. A evolução da concepção que os professores têm da comunicação matemática desempenhou, igualmente, um papel fundamental no seu conhecimento didáctico referente aos processos de aprendizagem, com grandes potencialidades para influenciar as práticas de sala de aula. No decurso do projecto, as práticas comunicativas dos professores evoluíram de forma significativa, passando estes a pautá-las, primordialmente, por padrões de interacção baseados na discussão, associados à comunicação reflexiva, a partir da resolução de tarefas de natureza problemática. Ao longo do projecto, os professores desenvolveram a sua capacidade de reflexão, evoluindo para formas mais exigentes e sistemáticas, como a pesquisa e a investigação da sua prática, a partir dos problemas por eles identificados. Este estudo indica também que a realização de investigação por professores é facilitada pelo contexto colaborativo e, sobretudo, se estes a integrarem de forma orgânica na sua prática profissional, permitindo a compreensão e a resolução dos problemas profissionais. A colaboração e a autonomia dos professores evoluíram de modo inter-relacionado, não se registando conflito ou antagonismo entre ambas. Estas duas capacidades profissionais relacionam-se de forma dialéctica entre si e com o conhecimento didáctico, as práticas e a reflexão, promovendo um desenvolvimento integrado dos professores.

Although the spatiotemporal oscillations of the Greenland Ice Sheet (GrIS) during the last millennia have played a prominent role in global environmental changes, its glacial response to the natural variability still needs to be better constrained. Here, we focused on the reconstruction of the glacial behavior and deglaciation process along the Tyroler Valley (74° N, 22° E), within the Northeast Greenland National Park. This NW-SE valley connects with the GrIS via the Pasterze Glacier and divides two ice caps (A.P. Olsen Land and Payer Land), this last one feeding two piedmont glaciers (Copeland and Kløft glaciers). For this study, we combined the interpretation of the spatial pattern of geomorphological features and the chronological framework defined by a new dataset of 15 10Be cosmic-ray exposure (CRE) ages from glacially polished bedrock surfaces and moraine boulders together with one optically stimulated luminescence (OSL) age of a glaciolacustrine deposit. CRE ages indicate that the deglaciation of the lowest parts of the valley and the exposure of the highest slopes took place during the Early Holocene, at ca. 10–8.5 ka (ka = thousand year [BP]). Furthermore, this ice thinning also favored the disconnection of the valley tributary glaciers. Samples from the moraines of the two tributary glaciers indicate that the deglaciation was not continuous, but it was interrupted by at least three phases of glacial advance during the Neoglacial cooling (before ca. 5.9 ka), and the Little Ice Age (LIA, 0.6, and 0.3 ka). The larger piedmont glacier (Copeland Glacier) occupied the valley floor during these major advances, damming the river and allowing the formation of a proglacial glacial lake upvalley, as confirmed by the OSL date of lacustrine sediments that yielded an age of 0.53 ± 0.06 ka. In short, our study provides new evidence of the relative stability of GrIS and the regional ice caps in the area, in which glacial fronts have been rather stable since their advances during the Neoglacial and the LIA.

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