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- Recent evolution of the tidal prisms at the inlets of the western sector of the Ria Formosa, south coast of PortugalPublication . Jacob, J.; Cravo, AlexandraThe Ria Formosa is a coastal lagoon comprising six tidal inlets. The western sector encompassing three inlets, Ancao, Faro-Olhao and Armona is the most important one since it represents approximately 90% of the total tidal prism. The Ancao inlet is characterized by a cyclic eastward migration pattern, but until now the knowledge of the real impact of its dynamics in the last 20 years in terms of tidal prisms and interconnectivity between these three inlets is scarce. This work presents the most exhaustive data set acquired so far, comprising 25 field surveys led in the period 2004-2013 on the western sector of Ria Formosa. This provides a long-term analysis of the recent temporal evolution of the tidal prisms from the three inlets during a single migration cycle (18 years) of the Ancao inlet. It determines the relative contribution of the three inlets to the total prism of the western sector of Ria Formosa before the last artificial opening of the Ancao inlet. Results show that at Ancao inlet the tidal prism decreased in spring tide mainly due to its eastward migration. The other natural inlet, Armona inlet, depict a progressive narrowing responsible for the decrease of the tidal prism in neap tide while during the same tidal phase, at the Faro-Olhao inlet, the most important one in terms of exchanges, the tidal prism increased. Those alterations at the three inlets could be related to morphodynamic changes and morphological evolution and confirmed the strong interconnectivity between them to compensate the variations of their relative contributions to the total prism. The tidal prisms errors were low for all cases (< 10%) and confirm that, globally, there was an increase of the prisms with time.
- Reconstruction of surface water dynamics in the North Atlantic during the Mid-Pleistocene (similar to 540-400 ka), as inferred from coccolithophores and planktonic foraminiferaPublication . Martinez-Sanchez, Marta; Flores, Jose-Abel; Palumbo, Eliana; Alonso-Garcia, Montserrat; Sierro, Francisco-Javier; Amore, Filomena OrnellaChanges in paleoclimate and paleoproductivity patterns have been identified by analyzing the coccolithophore assemblages from the IODP Site U1314, located in the subpolar North Atlantic, together with other proxy data available during the time interval from the Marine Isotope Stages (MIS) 14 to MIS 11 (ca. 540 to 400 ka). The comparison of this data with that of MD03-2699, located off the Iberian Margin, allowed us to study their common response to environmental changes in terms of paleoproductivity and temperature variability. Statistical analyses of the composition of coccolithophore assemblages revealed that the calcareous plankton dynamics were mainly driven by eccentricity, which controlled the alternating migration of the Polar Front (PF) and the North Atlantic Current (NAC) at glacial-interglacial timescales. The high frequency variability of paleoproductivity, over imposed onto glacial/interglacial variability at both sites, were related to NAC intensifications on a precessional timescale. The northward (southward) migration of the PF caused a strengthening (weakening) of the NAC, which created an intensification (weakening) of the Irminger Current (IC) at Site U1314 and the Portugal Current (PC) at MD03-2699. Furthermore, low-latitude processes have been shown to influence climate in the high-latitude during the late Pleistocene. During MIS 14 and 12, enhanced glacial strength affected both coccolithophores and planktonic foraminifera, indicating a southward movement of the NAC. Using the same proxies, a northward movement of the NAC is recorded during MIS 13 and 11. Alternatively, the spectral analyses performed on calcareous plankton assemblages allowed the identification of a pattern of periodic response of the plankton at the orbital and, in some cases, millennial level, as well as abrupt Heinrich-type time-scale variability during Termination V (TV). This was the most extreme event and was related to a massive iceberg discharge from high to mid-latitudes.
- Reply to "Comment on "Stratigraphy of the Northern Pulo do Lobo Domain, SW Iberia Variscides: A palynological contribution" by Zelia Pereira et al. (2018) - Geobios 51, 491-506"Publication . Pereira, Zelia; Manuel Carvalho Fernandes, Paulo; Matos, Joao X.; Jorge, Raul C. G. S.; Oliveira, Jose T.We acknowledge M. Francisco Pereira, D. Martínez Poyatos, I. Pérez-Cáceres, Cristina Gama and António Azor for the interest shown in our work, and appreciate the chance to clarify a few questions raised by Pereira et al.’s (2018) research. The main aim of Pereira et al. (2018) study was to better constrain the ages of the lithostratigraphic units that make the Northern Pulo do Lobo Domain, SW Iberia Variscides.
- Exploring the cytotoxic activity of new phenanthroline salicylaldimine Zn(II) complexesPublication . Matos, Cristina P.; Addis, Yemataw; Nunes, Patrique; Barroso, Sonia; Alho, Irina; Martins, Marta; Matos, Antonio P. A.; Marques, Fernanda; Cavaco, Isabel; Pessoa, Joao Costa; Correia, IsabelZinc(II) complexes bearing N-salicylideneglycinate (Sal-Gly) and 1,10-phenanthroline (phen) or phenanthroline derivatives [NN= 5-chloro-1,10-phenanthroline, 5-amine-1,10-phenanthroline (amphen), 4,7-diphenyl-1,10-phenanthroline (Bphen) and 5,6-epoxy-5,6-dihydro-1,10-phenanthroline] are synthesized. Complexes formulated as [Zn(NN)(2)(H2O)(2)](2+) (NN = phen and amphen), are also prepared. The cytotoxicity of the compounds is evaluated towards a panel of human cancer cells: ovarian (A2780), breast (MCF7) and cervical (HeLa), as well as non-tumoral V79 fibroblasts. All compounds display higher cytotoxicity than cisplatin (IC50 = 22.5 +/- 5.0 mu M) towards ovarian cells, showing IC50 values in the low micromolar range. Overall, all compounds show higher selectivity for the A2780 cells than for the non tumoral cells and higher selectivity indexes (IC50(V79)/IC50(A2780) than cisplatin. [Zn(Sal-Gly)(NNI(H2O)] complexes induce caspase-dependent apoptosis in A2780 cells, except [Zn(Sal-Gly)(Bphen)(H2O)], one of the most cytotoxic of the series. The cellular uptake in the ovarian cells analyzed by Inductively Coupled Plasma mass spectrometry indicates different Zn distribution profiles. Transmission electronic microscopy shows mitochondria alterations and apoptotic features consistent with caspase activationells incubated with EZn(Sal-Gly)(amphen)(H2O)] present additional nuclear membrane alterations in agreement with significant association with the nucleus. The increase of reactive oxygen species and lipid peroxidation forms could be related to apoptosis induction. [Zn(NN)(2)(H2O)(2)](2+) complexes have high ability to bind DNA through intercalation/groove binding, and circular dichroism data suggests that the main type of species that interact with DNA is [Zn(NN)](2+). Studies varying the % of fetal bovine serum (1-15%) in cell media show that albumin binding decreases the complex activity, indicating that distinct speciation of Zn- and phen-containing species in cell media may affect the cytotoxicity.
- Phytochemical characterization and bioactivities of five Apiaceae species: Natural sources for novel ingredientsPublication . Zengin, Gokhan; Mahomoodally, Mohamad Fawzi; Paksoy, Mehmet Yavuz; Picot-Allain, Carene; Glamocilja, Jasmina; Sokovic, Marina; Diuzheva, Alina; Jeko, Jozsef; Cziaky, Zoltan; Rodrigues, Maria Joao; Sinan, Kouadio Ibrahime; Custódio, LuísaSeveral species of the Apiaceae family have been employed in traditional cultures for their curative virtues. The present study focused on five Apiaceae species, (Falcaria vulgaris (FV), Smyrniopsis aucher( (SA), Smyrniopsis mtutzurdagensis (SM), Smyrnium cordifolium (SC), and Actinolema macrolema (AM)). The antioxidant, enzyme inhibitory (alpha-amylase, alpha-glucosidase, acetyl- and butyrylcholinesterase, lipase, and tyrosinase), antimicrobial, phytochemical, and cytotoxicity profiles of the methanol extracts of the selected Apiaceae species were determined. SC extract (35.68 mg gallic acid equivalent/g extract) possessed the highest phenolic content while the AM extract (56.79 mg rutin equivalent/g extract) had the highest flavonoid content. HPLC-ESI-MS (High performance liquid chromatography-electrospray tandem mass spectrometry) analyses showed presence of ferulic acid in all the five species. SC extract exhibited high radical scavenging (59.28 and 94.31 mg Trolox equivalent [TE]/g extract, DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid), respectively) and reducing activity (161.44 and 113.62 mg TE/g extract, for CUPRAC (cupric reducing antioxidant capacity) and FRAP (ferric reducing antioxidant power), respectively). SM extract exhibited the highest cholinesterase's inhibitory action (3.82 and 4.76 mg galantamine equivalent/g extract, for acetyland butyrylcholinesterase, respectively). The extracts showed higher inhibition against alpha-glucosidase (7.32-11.99 mmol acarbose equivalent [ACAE]/g extract) compared to alpha-amylase (0.51-0.55 mmol ACAE/g extract). SC extract was the most active (137.54 mg kojic acid equivalent/g extract) tyrosinase inhibitor and FV extract (113.75 mg Orlistat equivalent/g) the best lipase inhibitor. SM extract showed potent antibacterial effect against B. cereus (MIC (minimum inhibitory concentration) 0.180 mg/mL), P. mirabilis (MIC 0.180 mg/mL), M. flavus (MIC 0.560 mg/mL), P. aeruginosa (MIC 0.275 mg/mL), and S. typhimurium (MIC 1.500 mg/mL). FV extract (MIC 0.140 mg/mL) suppressed A. fumigates growth. Cytotoxicity was assessed on murine macrophage (RAW 264.7), human embryonic kidney (HEK 293), and human hepatocellular carcinoma (HepG2) cell lines. FV (60.3%) and SM (57.4%) showed the highest reduction on RAW 264.7 cellular viability, whereas SM (74.1%) showed toxicity against HepG2. This study supports that the Apiaceae species could be considered as promising candidates for the development of novel pharmacophores for the management of several human ailments.
- Valuation of aesthetic ecosystem services of protected coastal dunes and forestsPublication . Urbis, Arvydas; Povilanskas, Ramunas; Newton, AliceThis study was implemented in the context of the emerging concept of aesthetic ecosystem services (AES) of coastal protected dunes and forests. The main problem addressed was that many coastal management research case studies focusing on AES still rely on the objectivist paradigm, eliciting aesthetic values based on objective sets of criteria independent from human perception 'here and now'. This doesn't use the knowledge accrued from several decades of psychophysical studies in landscape aesthetics using photographs as visual stimuli, due to the complexity of the psychophysical approach. The study bridges this major research gap by eliciting the preferences for and the attractiveness of coastal landscapes that are founded in the landscape's physical attributes. An innovative 'quali-quantitative' methodology was applied, combining both quantitative (paired comparison survey) and qualitative (semi-structured in-depth interviews) methods for valuation and interpretation of coastal AES. The main aim of the study was to test a 'quali-quantitative' methodology for the valuation of AES of protected coastal dunes and forests, using the Curonian Spit (Lithuania) as a case study. The key finding of the quantitative survey was that domestic summer visitors found the open landscapes of the Curonian Spit most attractive, especially 1) White mobile dunes 2) White dunes with grey dunes in the background 3) Grey dunes with white dunes in the background. The main result of the qualitative survey was that local stakeholders living on the Curonian Spit consider the concept of visual coherence as best explaining the aesthetic appeal of the dune and forest landscapes on the spit. The main associated policy recommendation to coastal management policy-makers on the Curonian Spit, and in other protected coastal dune areas, is to pay more attention to AES along with the care for biodiversity conservation and for other tangible dune ecosystem services.
- Cinetorhynchus gabonensis, a new species of hinge-beak shrimp (Crustacea: Decapoda: Rhynchocinetidae) from the eastern AtlanticPublication . Duris, Zdenek; Sobanova, Anna; Wirtz, PeterA new species of the rhynchocinetid genus Cinetorhynchus, C. gabonensis sp. n. from the Atlantic waters of Gabon, is described based on morphological and molecular comparisons and its distinctive colour pattern. This is the second known species of the genus in the eastern Atlantic, and the third species in the Atlantic as the whole. The new species is more closely related to the western Atlantic C. manningi, both having quadrispinose ambulatory dactyli (i.e. with unguis + 3 ventral spinules), but differs from the latter by the presence of an arthrobranch on the three anterior pereiopods (vs only on the first pereiopod in C. manningi). The branchial formula of the new species is consistent with most of the Indo-West Pacific congeners, and with the amphi-Atlantic C. rigens
- The preburning condition of Chalcolithic cremated human remains from the Perdigoes enclosures (Portugal)Publication . Godinho, Ricardo Miguel; Goncalves, David; Carlos Valera, AntónioThe Iberian Chalcolithic displayed a remarkable variety of funerary practices, which has been related to interpopulation differences, intrapopulation social-cultural differences, and complex multistage funerary rituals. Perdigoes, a Chalcolithic set of ditched enclosures, reflects such diversity including a wide array of funerary practices. Among those practices is cremation, which, despite relatively rare, is represented in different structures in Perdigoes. One of these structures (Pit 40) presents an unparalleled high minimum number of individuals (n = 240), contrasting with nearby and coeval structures. In this study, we analyse heat-induced bone changes and other archaeothanatological variables to tentatively assess the preburning condition of the human remains. The results of Pit 40 are also compared with other comparable contexts to assess if this unique context presents further funerary differences relative to those other contexts in, for example, body processing. Our results suggest preferential cremation of fleshed human remains, but burning of at least a minority of skeletonised remains and deposition of possibly unburned remains also likely occurred. Body processing appears to be comparable with that of the cremation contexts of Perdigoes but contrasts with that of another nearby context (Dolmen of Olival da Pega 2b) in which burned bones were also found.
- Modelling long-term fisheries data to resolve the attraction versus production dilemma of artificial reefsPublication . Roa-Ureta, Ruben H.; Santos, Miguel N.; Miguel de Sousa Leitão, FranciscoThe main role of artificial reefs (ARs) is to enhance the productivity and sustainability of coastal fisheries by creating new fish biomass. From a modelling point of view, the creation of new fish biomass would be realized by a shift to a state of higher carrying capacity of the environment (K) for aquatic populations and communities. However, it has not been possible to demonstrate unequivocally rising K as a result of AR deployment because of the difficulty in disentangling enhancements due to simple distributional changes (the attraction hypothesis) versus total abundance rise (the production hypothesis). Here we develop a modelling framework based on simple, inexpensive fisheries data to quantify the impact of ARs, disentangling attraction from production by assessing the rise in regional K. The rationale is that if attraction to ARs from the wider region was the main driver of increased abundance in the ARs then regional K would have remained constant before, during and after deployment of the ARs. Therefore an increase in regional K disproves the hypothesis of attraction. The study case is the fishery for the two-banded seabream Diplodus vulgaris in southern Portugal. Monthly time series of 27 years of landings, 20 years of fishing effort, were available from three small-scale fleets: one was the artisanal fleet operating on the ARs and the other two were semi-industrial fleets operating on the wider continental shelf. The model that we developed and applied incorporated the data from all fleets so it evaluated the change in regional K. We show that regional K for D. vulgaris increased by 35% after final deployment of the ARs and it did so in linear fashion during four years. From a fisheries perspective the result was more nuanced because although the deployment succeeded in raising regional K, stock biomass and thereby enhancing the artisanal fishery, it also led to a substantial rise in total fishing mortality and exploitation rate because the semi-industrial fleets operating offshore increased their harvest rate nearly 3-fold. Our modelling framework has wide applicability in other regions due to the elementary nature of the necessary fishing monitoring data.
- Transatlantic gradients in calcifying phytoplankton (coccolithophore) fluxesPublication . Guerreiro, Catarina V.; Baumann, Karl-Heinz; Brummer, Geert-Jan A.; Korte, Laura F.; Sa, Carolina; Stuut, Jan-Berend W.Tropical oceans provide a benchmark for future primary productivity in increasingly warmer, stratified and nutrient-depleted waters. In this context, we assess the export fluxes of calcifying phytoplankton (coccolithophores) across the tropical North Atlantic, from upwelling affected NW Africa, via three ocean sites along 12 degrees N to the Caribbean. Sampling was undertaken by means of a spatial array of four time-series sediment traps collecting particle fluxes in two-week intervals, from October 2012 to February 2014, allowing to track temporal changes along the southern margin of the North Atlantic central gyre. Species composition and seasonal export fluxes of coccolithophores show steep gradients in two groups. Upper photic zone (UPZ) and placolith-bearing species dominated by Emiliania huxleyi and Gephyrocapsa oceanica are most abundant in the mesotrophic surface waters of the Cape Blanc upwelling system off NW Africa. They decline gradually towards the Caribbean, paralleled by increasing surface temperatures and decreasing surface chlorophyll-a. Meanwhile the abundance of lower photic zone (LPZ) species Florisphaera profunda and Gladiolithus flabellatus increase in the same direction, reaching fluxes up to 3-5 times higher in the western end of the transect compared to the UPZ flora in mesotrophic waters. Adapted to low light conditions, the LPZ species follow the geostrophic wind-forced deepening of the thermocline/nutricline westward in ever lower species diversity towards the Caribbean. Temporal changes were marked by weak seasonality in coccolith fluxes at all four sites, modulated by latitudinal migration of the Intertropical Convergence Zone (ITCZ) at the tropical sites Ml, M2 and M4, and by spatiotemporal variation in wind-forced upwelling at site CB. A seasonal mismatch was observed between LPZ and UPZ-oligotrophic taxa (i.e. Umbellosphaera spp., Rhabdosphaera spp.) vs. UPZ-opportunistic species (E. huxleyi, G. oceanica) at the western site M4 contrasting with the more similar seasonal patterns amongst all species towards site CB. We interpret this as reflecting the entire photic zone becoming increasingly nutrient enriched towards east whenever wind-forced mixing occurs due to the eastward shoaling of the thermocline/nutricline. Our synoptic observations of seasonally resolved export fluxes at four sites contribute to the spatiotemporal understanding of coccolithophore fluxes across the entire tropical North Atlantic, urging for considering phytoplankton- and carbonate production across the entire photic zone when projecting the effects of ocean warming on future primary production.