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- The fishes of ascension Island, central Atlantic Ocean - new records and an annotated checklistPublication . Wirtz, Peter; Bingeman, Jane; Bingeman, John; Fricke, Ronald; Hook, Timothy J.; Young, JimmyA checklist of the fishes of Ascension Island is presented. The species Rhincodon typus, Alopias superciliosus, Isurus oxyrinchus, Carcharhinus obscurus, Galeocerdo cuvier, Sphyrna lewini, Hexanchus griseus, Manta birostris, Gymnothorax vicinus, Hippocampus sp., Epinephelus itajara, Cookeolus japonicus, Apogon pseudomaculatus, Phaeoptyx pigmentaria, Remora albescens, Caranx bartholomaei, Carangoides ruber, Decapterus tabl, Seriola dumerili, Thalassoma sanctaehelenae, Cryptotomus sp., Ruvettus pretiosus, Acanthocybium solandri, Auxis rochei, Auxis thazard, Euthynnus alletteratus, Katsuwonus pelamis, Thunnus alalunga, Thunnus obesus, Xiphias gladius, Istiophorus platypterus, Kajikia albida, Makaira nigricans, Tetrapturus pfluegeri, Hyperoglyphe perciformis, Schedophilus sp., Cantherhines macrocerus, Sphoeroides pachygaster and Diodon eydouxii are recorded for the first time from Ascension Island. We have recognized two previous records as identification errors and indicate 11 other records as doubtful. Including the 40 new records, we now list 173 fish species from Ascension Island, of which 133 might be considered 'coastal fish species'. Eleven of these (8.3%) appear to be endemic to the island and a further 16 species (12%) appear to be shared endemics with St Helena Island.
- IMMUNOLOGY Mind the immuno-connection gapPublication . Link, WolfgangBiologic drugs that modulate the immune system have revolutionized the therapeutic landscape for several selected cancer types. A new study reports an image-based assay system to monitor cell–cell interactions, identifying small-molecule compounds with immunomodulatory capacity.
- Marxan as a zoning tool for development and economic purposed areas - Aquaculture Management Areas (AMAs)Publication . Sales Henriques, Nuno; Monteiro, Pedro; Bentes, Luis; Oliveira, Frederico; Afonso, Carlos; Gonçalves, Jorge Manuel SantosThe increased number of human activities within the marine environment and the demand for maritime space has increased to a point where in some parts of the globe the demand for maritime space has exceeded the available area. The overlapping objectives and activities have caused severe conflicts among users and with the natural marine environment itself. For that reason, holistic strategies such as Ecosystem Based Management (EBM) and Maritime Spatial Planning (MSP) have been evolved and developed to sustainably manage the marine environment, avoiding conflicts and creating synergies. Spatial analysis tools like Marxan have been used for several years as decision support tools mostly for conservation plans, such as design and establishment of protected areas. In this study we approach the potential of this tool with a different purpose in mind: instead of using the available information of the region for the development of a conservation plan, we used this tool and the available information to select areas to establish Aquaculture Management Areas (AMAs). We also intended to analyse how the existing features of the region would affect the final result of a spatial plan aimed to establish areas for economic and development purposes. We conclude that the use of Marxan can be advantageous to support the planning and development of coastal regions, not only in a conservationist point of view (as it has been mostly used), but also into a developing and economic driven approach. This tool can be particularly useful in regions or situations where there is a large number of stakeholders, ecological and geographical features that could potentially conflict with the establishment, the management and the success of the proposed management areas. (C) 2017 Elsevier Ltd. All rights reserved.
- Physiological traits and oxidative stress markers during acclimatization of micropropagated plants from two endangered Plantago species: P-algarbiensis Samp. and P-almogravensis FrancoPublication . Gonçalves, Sandra; Martins, Neusa; Romano, A.Plantago algarbiensis Samp. and Plantago almogravensis Franco are species endemic to Portugal at risk of global extinction. The aim of this study was to investigate the ex vitro performance of micropropagated P. algarbiensis and P. almogravensis plants in terms of survival, relative water content (RWC), photosynthetic pigment contents, H2O2 accumulation, activities of superoxide dismutase (SOD) and catalase (CAT), lipid peroxidation, and soluble protein content, in comparison with wild-grown plants. Relatively high survival rates and RWC values during the acclimatization process were observed for both species. In P. algarbiensis, the pigment content increased when plantlets were transferred to ex vitro conditions, indicating enhanced light absorption capacity. No significant alterations in H2O2 content, CAT activity, or lipid peroxidation level were observed during acclimatization, but the protein content decreased in plants at the end of the growth chamber and greenhouse stages. When P. almogravensis plantlets were transferred to the ex vitro environment, decreases in the H2O2 content were observed that correlated to increased CAT activity and SOD maintenance, which lead to decreased lipid peroxidation and protein content. It was concluded that micropropagated P. algarbiensis and P. almogravensis plants were able to manage the oxidative stress induced by the in vitro environment and to perform well under ex vitro conditions.
- Early survival of Quercus ilex subspecies from different populations after infections and co-infections by multiple Phytophthora speciesPublication . Corcobado, T.; Miranda-Torres, J. J.; Martin-Garcia, J.; Jung, Thomas; Solla, A.Forests in Europe are threatened by increased diversity of Phytophthora species, but effects on trees of simultaneous infections by Phytophthora and ecological consequences of their coexistence are unknown. This study explored variation in early survival of Quercus ilex to Phytophthora infections and assessed interactions between Phytophthora species when trees were co-infected. Three Phytophthora species (P. cinnamomi, P. gonapodyides and P. quercina), seeds from 16 populations of Q. ilex (ballota and ilex subspecies) and two infection times were used as sources of variation in two experiments. The influence of Phytophthora species, Q. ilex subspecies and populations on plant germination and survival were analysed using generalized linear mixed models and survival analysis techniques. Germination rates were not influenced by Phytophthora spp. (P = 0.194) but by the subspecies and populations of Q. ilex (P < 0.001). In Phytophthora-infested soils, Q. ilex subsp. ilex germinated at higher rates than Q. ilex subsp. ballota. Plant survival was strongly influenced by Phytophthora species (P < 0.001), not by the subspecies and populations of Q. ilex. Seedling mortality was reduced and delayed if a less virulent Phytophthora species infected plants prior to infection by a more virulent Phytophthora species. The results help to explain oak decline syndrome and the lack of natural and artificial regeneration of Q. ilex forests. Lack of interspecific variability of early survival to Phytophthora spp. discourages direct sowing for artificial reforestation programmes. Large, thick seeds, giving plants rapid growth, are advantageous traits when soils are infested with Phytophthora spp.
- Six new Phytophthora species from ITS Clade 7a including two sexually functional heterothallic hybrid species detected in natural ecosystems in TaiwanPublication . Jung, Thomas; Horta, Marília; Scanu, B.; Seress, D.; Kovacs, G. M.; Maia, Cristiana; Perez-Sierra, A.; Chang, T. -T.; Chandelier, A.; Heungens, K.; van Poucke, K.; Abad-Campos, P.; Leon, M.; Cacciola, S. O.; Bakonyi, J.During a survey of Phytophthora diversity in natural ecosystems in Taiwan six new species were detected. Multigene phylogeny based on the nuclear ITS, beta-tubulin and HSP90 and the mitochondrial cox1 and NADH1 gene sequences demonstrated that they belong to ITS Clade 7a with P. europaea, P. uniformis, P. rubi and P. cambivora being their closest relatives. All six new species differed from each other and from related species by a unique combination of morphological characters, the breeding system, cardinal temperatures and growth rates. Four homothallic species, P. attenuata, P. flexuosa, P. formosa and P. intricata, were isolated from rhizosphere soil of healthy forests of Fagus hayatae, Quercus glandulifera, Q. tarokoensis, Castanopsis carlesii, Chamaecyparis formosensis and Araucaria cunninghamii. Two heterothallic species, P. xheterohybrida and P. xincrassata, were exclusively detected in three forest streams. All P. xincrassata isolates belonged to the A2 mating type while isolates of P. xheterohybrida represented both mating types with oospore abortion rates according to Mendelian ratios (4-33 %). Multiple heterozygous positions in their ITS, beta-tubulin and HSP90 gene sequences indicate that P. xheterohybrida, P. xincrassata and P. cambivora are interspecific hybrids. Consequently, P. cambivora is re-described as P. xcambivora without nomenclatural act. Pathogenicity trials on seedlings of Castanea sativa, Fagus sylvatica and Q. suber indicate that all six new species might pose a potential threat to European forests.
- Altered epiphyte community and sea urchin diet in Posidonia oceanica meadows in the vicinity of volcanic CO2 ventsPublication . Nogueira, Patrícia; Gambi, Maria Cristina; Vizzini, Salvatrice; Califano, Gianmaria; Tavares, Ana Mafalda; Santos, Rui; Martinez-Cruz, BegonaOcean acidification (OA) predicted for 2100 is expected to shift seagrass epiphyte communities towards the dominance of more tolerant non-calcifying taxa. However, little is known about the indirect effects of such changes on food provision to key seagrass consumers. We found that epiphyte communities of the seagrass Posidonia oceanica in two naturally acidified sites (i.e. north and south sides of a volcanic CO2 vent) and in a control site away from the vent at the Ischia Island (NW Mediterranean Sea) significantly differed in composition and abundance. Such differences involved a higher abundance of non-calcareous crustose brown algae and a decline of calcifying polychaetes in both acidified sites. A lower epiphytic abundance of crustose coralline algae occurred only in the south side of the vents, thus suggesting that OA may alter epiphyte assemblages in different ways due to interaction with local factors such as differential fish herbivory or hydrodynamics. The OA effects on food items (seagrass, epiphytes, and algae) indirectly propagated into food provision to the sea urchin Paracentrotus lividus, as reflected by a reduced P. oceanica exploitation (i.e. less seagrass and calcareous epiphytes in the diet) in favour of non-calcareous green algae in both vent sites. In contrast, we detected no difference close and outside the vents neither in the composition of sea urchin diet nor in the total abundance of calcareous versus non-calcareous taxa. More research, under realistic scenarios of predicted pH reduction (i.e. <= 0.32 units of pH by 2100), is still necessary to better understand cascading effects of this altered urchin exploitation of food resources under acidified conditions on ecosystem diversity and function. (C) 2017 Elsevier Ltd. All rights reserved.
- Flow rate measurements under sluice gatesPublication . Silva, Carlos Otero; Rijo, ManuelSluice gates are commonly used in canals for control and measurement of the flow. The discharge under sluice gates can be determined through the energy-momentum method (EM), the orifice flow rate equations and the application of the.-theorem of the dimensional analysis. The different discharge methods available, for free and submerged hydraulic jump including the transition between flows, were compared with experimental data. The performance of the different calibration methods was analyzed. The test program was conducted in the laboratory flume and in the experimental irrigation canal of the University of vora, Portugal. The test program shows that the evaluation of the discharge under sluice gates for free and submerged flows and for the transition between both flows through the methods based in the EM were those who had better results. For the studied gates openings, the results also show that the methods that consider the division of the submerged flow in partial and totally submerged did not improve the discharge results. (C) 2017 American Society of Civil Engineers.
- Kinetic study of Friedel-Crafts acylation reactions over hierarchical MCM-22 zeolitesPublication . Aleixo, Rodrigo; Elvas-Leitao, Ruben; Martins, Filomena; Carvalho, Ana P.; Brigas, Amadeu; Martins, Angela; Nunes, NelsonFriedel-Crafts acylation was studied under mild conditions using hierarchical MCM-22 zeolites prepared by desilication and by desilication + acid treatment, using furan, pyrrole and anisole as substrates, and acetic anhydride as acylating agent. Enhanced catalysis was observed for furan and anisole, especially at short reaction times. Kinetic results modelling using non-linear regressions applied to a simplified Langmuir-Hinshelwood equation showed that desilication treatment followed by acid treatment improved kinetics (higher k and TOF). A QSPR methodology using nine substrate and zeolite descriptors was applied to model kinetics and adsorption. For both processes, the best QSPR model equations lead to the same descriptors, namely, Bronsted acidity, as zeolite's feature, and both van der Waals volume and Dimroth-Reichardt E-T(N) parameter (related to dipolarity and Lewis acidity) as substrates' characteristics. Normalization of descriptors allowed quantification of each descriptor's relative importance leading to a better understanding of the catalytic and adsorption processes. (C) 2017 Elsevier B.V. All rights reserved.
- Sex estimation with the total area of the proximal femur: A densitometric approachPublication . Curate, Francisco; Albuquerque, Anabela; Ferreira, Izilda; Cunha, EugeniaThe estimation of sex is a central step to establish the biological profile of an anonymous skeletal individual. Imaging techniques, including bone densitometry, have been used to evaluate sex in remains incompletely skeletonized. In this paper, we present a technique for sex estimation using the total area (TA) of the proximal femur, a two-dimensional areal measurement determined through densitometry. TA was acquired from a training sample (112 females; 112 males) from the Coimbra Identified Skeletal Collection (University of Coimbra, Portugal). Logistic regression (LR), linear discriminant analysis (LDA), reduce error pruning trees (REPTree), and classification and regression trees (CART) were employed in order to obtain models that could predict sex in unidentified skeletal remains. Under cross-validation, the proposed models correctly estimated sex in 90.2-92.0% of cases (bias ranging from 1.8% to 4.5%). The models were evaluated in an independent test sample (30 females; 30 males) from the 21st Century Identified Skeletal Collection (University of Coimbra, Portugal), with a sex allocation accuracy ranging from 90.0% to 91.7% (bias from 3.3% to 10.0%). Overall, data mining classifiers, especially the REPTree, performed better than the traditional classifiers (LR and LDA), maximizing overall accuracy and minimizing bias. This study emphasizes the significant value of bone densitometry to estimate sex in cadaveric remains in diverse states of preservation and completeness, even human remains with soft tissues. (C) 2017 Elsevier B. V. All rights reserved.