Habitat suitability model for european wild rabbit (Oryctolagus cuniculus) with implications for restocking

The European wild rabbit, Oryctolagus cuniculus, is a key species in the Iberian ecosystems. However, its populations are seriously depleted. Therefore, the development of habitat suitability models could be an important step towards the establishment of management and recovery plans. An habitat suitability model was developed for the rabbit in the 4,606 ha of the Peneda-Gerês National Park (northern Portugal). The framework was based on 3 steps: (1) construction of an habitat suitability model using the logistic regression of presence/absence of rabbits on habitat variables, (2) location of suitable habitat on a map, with the help of a Geographic Information System (GIS), by applying the above-obtained regression coefficients to the digitalized data of a land-cover map, and (3) delineation of the best potential sites for restocking. In June-July 2000, presence/absence of rabbits was determined by the presence/absence of pellets, warrens and individuals on 86 100-m radius random circular plots, i.e. 3.14 ha each representing the area occupied by a family group in summer. The initial dataset was divided into 56 sampling plots to build the model and 30 sampling plots (15 with rabbits and 15 without rabbits) for cross-validation. Measured habitat variables were % cover of tall scrubland, % cover of rocks, and interspersion (an index measuring the amount of intermixture of forage and shelter patches). These variables were calculated for all pixels of a digital land-cover map, using a moving 100-m radius window approach. Plots on which wild rabbits were present had a mean 10+3.4%(SE) percentage of rocks, 16.3+3.8% percentage of tall scrubland and an interspersion index of 0.9+0.09 (vs 1.3+0.7, 2.7+1.5 and 0.4+0.05 for “absence” plots, P 50%), distributed over 106 patches. Three clusters of suitable patches were delineated, assuming a critical threshold distance of 200 m between neighbour patches (distance equal to the mean dispersal ability of rabbits) for their inclusion into the same group. In that way, an area of 508.7 ha (11% of the study area) including the best potential site for restocking was delineated. Results suggested that management efforts should be aimed at promoting the connection between the three habitat-patch clusters. The framework presented provides a method for accurate and rapid assessment of habitats suitable for wild rabbit and could assist managers in identifying the best potential restocking sites

Decomposing the causes for niche differentiation between species using hypervolumes

Hutchinson's n-dimensional hypervolume concept holds a central role across different fields of ecology and evolution. The question of the amount of hypervolume overlap and differentiation between species is of great interest to understand the processes that drive niche dynamics, competitive interactions and, ultimately, community assembly. A framework is proposed to decompose overall differentiation among hypervolumes into two distinct components: niche shifts and niche contraction/expansion processes. Niche shift corresponds to the replacement of space between the hypervolumes occupied by two species, whereas niche contraction/expansion processes correspond to net differences between the amount of space enclosed by each hypervolume. A procedure to implement non-continuous trait data in the estimation ofn-dimensional hypervolumes is proposed. Hypervolumes were constructed for three Darwin' finches,Geospiza conirostris,Geospiza magnirostris, andGeospiza difficilisusing intraspecific trait data. Results showed that significant niche shifts, not niche contraction, occurred betweenG. conirostrisandG. magnirostrisin Genovesa island, where they live in sympatry. This means thatG. conirostrisoccupied a different niche space and not a reduced space on Genovesa.G. difficiliswas well differentiated from the other two species. The proposed framework allows disentangling different processes underlying niche partitioning between coexisting species. This framework offers novel insights to understand the drivers of niche partitioning strategies among coexisting species.Peer reviewe

South Gaulish terra sigillata in the forum of Aeminium (Coimbra, Portugal): a decisive component of the dating process

The Augustan forum of Aeminium (Coimbra, Portugal) underwent a significant enlargement in the middle of the 1st century AD. The extension was built over a monumental cryptoporticus located on steep terrain. Archaeological campaigns carried out at this site more or less continuously since the 1990s have identified the construction levels associated to this extension. This text presents the collection of red gloss pottery (terra sigillata) from South Gaul gathered in these stratigraphic contexts. The study of them, together with other chronological indicators, has enabled the second stage of construction of the forum of Aeminium to be dated to the mid 1st century AD.O fórum augustano de Aeminium (Coimbra, Portugal) terá sido significativamente ampliado em meados do século I d.C. Esse acrescento desenvolveu-se sobre um monumental criptopórtico que se instalou em terreno declivoso. As campanhas arqueológicas efectuadas neste local, de forma mais ou menos continuada desde a década de 90 do séc. XX, permitiram identificar os níveis de construção associados a esta ampliação. Neste texto, apresenta-se a colecção de terra sigillata sudgálica recolhida nesses contextos estratigráficos. O seu estudo, articulado com outros indicadores cronológicos, permite fixar o segundo momento de edificação do fórum de Aeminium em meados da primeira centúria da nossa era.info:eu-repo/semantics/publishedVersio

Production of Metabolites as Bacterial Responses to the Marine Environment

Bacteria in marine environments are often under extreme conditions of e.g., pressure, temperature, salinity, and depletion of micronutrients, with survival and proliferation often depending on the ability to produce biologically active compounds. Some marine bacteria produce biosurfactants, which help to transport hydrophobic low water soluble substrates by increasing their bioavailability. However, other functions related to heavy metal binding, quorum sensing and biofilm formation have been described. In the case of metal ions, bacteria developed a strategy involving the release of binding agents to increase their bioavailability. In the particular case of the Fe3+ ion, which is almost insoluble in water, bacteria secrete siderophores that form soluble complexes with the ion, allowing the cells to uptake the iron required for cell functioning. Adaptive changes in the lipid composition of marine bacteria have been observed in response to environmental variations in pressure, temperature and salinity. Some fatty acids, including docosahexaenoic and eicosapentaenoic acids, have only been reported in prokaryotes in deep-sea bacteria. Cell membrane permeability can also be adapted to extreme environmental conditions by the production of hopanoids, which are pentacyclic triterpenoids that have a function similar to cholesterol in eukaryotes. Bacteria can also produce molecules that prevent the attachment, growth and/or survival of challenging organisms in competitive environments. The production of these compounds is particularly important in surface attached strains and in those in biofilms. The wide array of compounds produced by marine bacteria as an adaptive response to demanding conditions makes them suitable candidates for screening of compounds with commercially interesting biological functions. Biosurfactants produced by marine bacteria may be helpful to increase mass transfer in different industrial processes and in the bioremediation of hydrocarbon-contaminated sites. Siderophores are necessary e.g., in the treatment of diseases with metal ion imbalance, while antifouling compounds could be used to treat man-made surfaces that are used in marine environments. New classes of antibiotics could efficiently combat bacteria resistant to the existing antibiotics. The present work aims to provide a comprehensive review of the metabolites produced by marine bacteria in order to cope with intrusive environments, and to illustrate how such metabolites can be advantageously used in several relevant areas, from bioremediation to health and pharmaceutical sectors

Revista Portuguesa de Arqueologia

Em Coimbra os contextos tardo-antigos eram, até ao momento, pouco ou mesmo nada conhecidos. Contudo, face à importância da cidade antiga e ao que se conhecia para a vizinha Conimbriga, supunha-se que esta ausência poderia ser apenas aparente. Um estudo mais circunstanciado do que resultou das últimas intervenções arqueológicas realizadas no espaço do Museu Nacional de Machado de Castro, assim como o reexame de outras mais antigas (mediante a análise de um lote de materiais ainda não estudado), veio comprovar isso mesmo. Apresentam-se, assim, os dados dos ainda parcos contextos tardios identificados nesta notável área arqueológica, de onde provém um conjunto de espólio característico e que poderá fornecer as primeiras pistas acerca da ocupação e dinâmica comercial de Aeminium entre a segunda metade do século IV e os inícios do século VI.Until now very little or nothing was known about Late Antiquity contexts in the city of Coimbra. However, the importance of the old city and what is known about the neighboring Conimbriga led us to assume that this absence was merely apparent. This hypothesis was proved true, after a more detailed study of data from the last archaeological interventions at the Museum Machado de Castro and the reexamination of unstudied lots of materials from earlier interventions at the same site. This text presents the data from the few Late Antiquity contexts identified in this remarkable archaeological area. The materials collected are characteristic from the second half of the 4th century and early 6th century AD and they provide the first clues about the commercial dynamics of Aeminium in that period

The forums of Conimbriga and Aeminium: comparison and summary of the state of the art.

This paper presents the forums of the Roman cities of Conimbriga (Condeixa-a-Velha, Portugal) and Aeminium (Coimbra, Portugal), both of which date from the time of Augustus. The Aeminium forum was completely rebuilt in the time of Claudius/Nero, while the Conimbriga one was remodelled in the same period, before being demolished under the Flavians to make way for a completely new construction. This article offers a state-of-the-art comparison of the architectural models used in these two cities, based on the analysis and review of the available data, partly supplied by recent archaeological excavations. The geographic and chronological proximity of these two forums mean that it is of interest to compare their architectural design, which differ considerably in aspects such as volumetry, layout and the conceptual model used. The article discusses the proposals for the development of the Conimbriga forum and indicates an up-to-date bibliography for both public spaces, resulting, in the case of Aeminium, from a large-scale research and intervention project carried out in recent years

Sistemas dunares do litoral de Esposende

Ciência Viva - A.N.C.C.T. (Programa Operacional Ciência Tecnologia Inovação - POCTI)Ministério da Ciência e da Tecnologia - Ciência Viva - Biologia no Verão 2001

QM/MM MD studies of polyester synthesis/hydrolysis

The world is suffering the consequences of plastic pollution, however modern societies remain heavily reliant on plastics. More sustainable alternatives are actively being sought-after. Enzymatic synthesis can offer a more sustainable route for polyester synthesis. Nevertheless, there are still limitations, such as limited activity and selectivity for some monomers, unfavorable compatibility in chemoenzymatic reactions and low stability under harsh reactions conditions. We have studied the catalytic mechanisms for polycaprolactone hydrolysis/synthesis by the wildtype enzymes Archaeoglobus fulgidus carboxylesterase (AfEST) and Candida antarctica lipase B (CaLB) and respective enzyme variants by performing Quantum Mechanics/Molecular Mechanics Molecular Dynamics simulations [1-3]. Our results give important insights towards the design of new enzyme variants combining good activity with high thermostability. [1] Almeida, B., Figueiredo, P., Carvalho, A. PCL enzymatic hydrolysis: a mechanistic study. ACS Omega. Doi: 10.1021/acsomega.9b00345. [2] Carvalho, A. T. P., Dourado, D. F. A. R., Skvortsov, T., de Abreu M., Ferguson, L. J., Quinn, D. J., Moody, T. S. Huang, M. Spatial requirement for PAMO for transformation of non-native linear substrates. Phys. Chem. Chem. Phys. 2018. [3] Dourado D. F. A. R., Swart M., Carvalho A. T. P. Why the flavin dinucleotide cofactor needs to be covalently linked to Complex II of the electron transport chain for conversion of FADH2 to FAD. Chem. – Eur J. 2018