Browsing by Issue Date, starting with "2021-07-01"
Now showing 1 - 3 of 3
Results Per Page
Sort Options
- Unravelling hybridization in Phytophthora using phylogenomics and genome size estimationPublication . Van Poucke, Kris; Haegeman, Annelies; Goedefroit, Thomas; Focquet, Fran; Leus, Leen; Horta Jung, Marília; Nave, Corina; Redondo, Miguel A.; Husson, Claude; Kostov, Kaloyan; Lyubenova, Aneta; Christova, Petya; Chandelier, Anne; Slavov, Slavcho; de Cock, Arthur; Bonants, Peter; Werres, Sabine; Palau, Jonàs O.; Marçais, Benoit; Jung, Thomas; Stenlid, Jan; Ruttink, Tom; Heungens, KurtThe genus Phytophthora comprises many economically and ecologically important plant pathogens. Hybrid species have previously been identified in at least six of the 12 phylogenetic clades. These hybrids can potentially infect a wider host range and display enhanced vigour compared to their progenitors. Phytophthora hybrids therefore pose a serious threat to agriculture as well as to natural ecosystems. Early and correct identification of hybrids is therefore essential for adequate plant protection but this is hampered by the limitations of morphological and traditional molecular methods. Identification of hybrids is also important in evolutionary studies as the positioning of hybrids in a phylogenetic tree can lead to suboptimal topologies. To improve the identification of hybrids we have combined genotyping-by-sequencing (GBS) and genome size estimation on a genus-wide collection of 614 Phytophthora isolates. Analyses based on locus- and allele counts and especially on the combination of species-specific loci and genome size estimations allowed us to confirm and characterize 27 previously described hybrid species and discover 16 new hybrid species. Our method was also valuable for species identification at an unprecedented resolution and further allowed correct naming of misidentified isolates. We used both a concatenation- and a coalescent-based phylogenomic method to construct a reliable phylogeny using the GBS data of 140 non-hybrid Phytophthora isolates. Hybrid species were subsequently connected to their progenitors in this phylogenetic tree. In this study we demonstrate the application of two validated techniques (GBS and flow cytometry) for relatively low cost but high resolution identification of hybrids and their phylogenetic relations.
- Avaliação económica de programas de Reabilitação Respiratória em doentes respiratórios crónicos: impacto no Serviço Nacional de SaúdePublication . Ramalho, João Miguel dos Santos; Nunes, RuiEm Portugal, as doenças respiratórias crónicas, em particular a doença pulmonar obstrutiva cronica (DPOC), tem uma expressão significativa no quadro de doenças diagnosticadas. Face à escassez de recursos e ao aumento crescente das necessidades da população, a pressão sobre os serviços de saúde tem aumentado significativamente, pelo que se torna premente uma utilização eficiente dos recursos disponíveis para que, a custos razoáveis, seja possível obter verdadeiros ganhos em saúde. Assim, perceber qual o verdadeiro impacto económico no SNS decorrente da utilização eficiente de recursos no tratamento da DPOC, mais especificamente, a implementação de programas de reabilitação respiratória, é deveras relevante. De modo a proceder à avaliação económica deste tipo de programas, recorreu-se a modelos de simulação de Markov e análise custo-efectividade, onde para diferentes cenários hipotetizados foram relacionados os custos decorrentes destes programas com a sua efectividade, número de internamentos evitados, comparando com a terapêutica convencional. Através da análise de rácios incrementais custo-efectividade, verificou-se que os cenários hipotetizados são custo-efectivos, por apesar de apresentarem mais custos apresentarem também mais benefícios. No entanto, ao comparar o custo por internamento evitado com o custo de um internamento, este valor é bastante superior mesmo para o melhor cenário (9791,50€ vs. 4258,78€). Ao aumentar a eficácia da terapêutica estes rácios tornam-se mais aceitáveis, sendo para o melhor cenário, menores que o custo de internamento de um doente no estadio mais grave. Esta avaliação atende apenas ao impacto nos internamentos evitados, pelo que o real impacto da reabilitação respiratória se encontra subestimado, podendo ser avaliada à luz dessa mesma medida de efectividade.
- Crossing heritages: drystone walls in cultural tourism and geo-tourismPublication . Rosendahl, Stefan; Mallafrè Balsells, Cèlia; Marçal Gonçalves, MartaThe aim of cultural tourism is the cultural heritage. This heritage can consist of monuments in cities, for instance, and also of vernacular heritage which is found in rural areas. The drystone walls, often existing in regions where slopes prevail, are splendid examples of this group of heritage. Their role in cultural vernacular heritage is that they are made by man to make agriculture possible in difficult terrain creating plane areas in slopes, to retain surface and subsurface water as a reserve e.g. for the plantation and protection against wildfires, to protect agricultural areas in lower places against falling rocks and erosion by torrents, and so on. On the other hand, they also belong to the natural geological heritage because they are made of local stones, the geological setting of an area determines if such a wall is necessary or not, they interfere with the surface and subsurface water flows, they slow down erosional processes, they mould typical landscapes, and they create a lot of ecological niches and habitats for animals and plants. Therefore, drystone walls represent a link between cultural-vernacular and natural-geological heritage. Stone wall terraces are an expression of the history and the culture of the local people and present environmental, social and economic benefits. They may offer touristic opportunities, contributing to their renewal and survival. Their cultural value was recognized by the UNESCO in 2018 by the declaration of the “art of drystone walling, knowledge and techniques” as Intangible Cultural Heritage of Humanity.