Antioxidant and antitumor potential of wild and IMTA-cultivated Osmundea pinnatifida

Osmundea pinnatifida is a red edible seaweed known as pepper dulse. O. pinnatifida was cultivated in the farm of ALGAplus(Ilhavo, Portugal). This farm is integrated with a seabream and seabass commercial aquaculture and uses the nutrient-enriched water resultant from the fish production as its cultivation medium in the integrated multi-trophic aquaculture(IMTA) manner. Wild and IMTA-cultivated samples of O. pinnatifida were screened for antioxidant and antitumor activities. The antioxidant capacity of solvent extracts from wild and IMTA cultivated samples was assessed in two methods(2,2-diphenyl-1-picrylhydrazyl(DPPH) and oxygen radical absorbance capacity(ORAC)), and their total phenolic contents(TPC) were estimated. Antitumor activity was evaluated in three different tumor cell lines(HepG-2, MCF-7, and SH-SY5Y) through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay. Among the solvents used for extraction, dichloromethane was the most effective to extract phenolic compounds and presented higher ORAC. A significant correlation was found between TPC and ORAC,which was also sustained by the principal components analysis(PCA). Dichloromethane extracts induced a cytostatic effect on MCF-7 cells and showed weak cytotoxicity to SH-SY5Y cells and weak impact on cell proliferation. Overall, there were no statistically significant differences in the biological activities shown by the wild and IMTA-cultivated samples. Hence, O. pinnatifida can be obtained in an economical and environmentally sustainable way through IMTA, maintaining bioactive properties in a high potential for further nutraceutical purposes.     

Integrated 3D forward stratigraphic and petroleum system modeling of the Levant Basin,Eastern Mediterranean

The Eastern Mediterranean Levant Basin is a proven hydrocarbon province with recent major gas discoveries. To date, no exploration wells targeted its northern part, in particular the Lebanese offshore. The present study assesses the tectono‐stratigraphic evolution and related petroleum systems of the northern Levant Basin via an integrated approach that combines stratigraphic forward modeling and petroleum systems/basin modeling based on the previous published work. Stratigraphic modeling results provide a best‐fit realisation of the basin‐scale sedimentary filling, from the post‐rift Upper Jurassic until the Pliocene. Simulation results suggest dominant eastern marginal and Arabian Plate sources for Cenozoic siliciclastic sediments and a significant contribution from the southern Nilotic source mostly from Lower Oligocene to Lower Miocene. Basin modeling results suggest the presence of a working thermogenic petroleum system with mature source rocks localised in the deeper offshore. The generated hydrocarbons migrated through the deep basin within Jurassic and Cretaceous permeable layers towards the Latakia Ridge in the north and the Levant margin and offshore topographic highs. Furthermore, the basin model indicates a possibly significant influence of salt deposition during Messinian salinity crisis on formation fluids. Ultimately, the proposed integrated workflow provides a powerful tool for the assessment of petroleum systems in underexplored areas.     

Artificial Fracture Stimulation of Rock Subjected to Large Isotropic Confining Stresses in Saline Environments: Application in Deep-Sea Gas Hydrate Recovery

Natural Resources Research - The low permeability of gas hydrate deposits leads to poor extraction rates. Artificial fracture stimulation could significantly improve the recovery rate of an...     

Linking shock textures revealed by BSE,CL, and EBSD with U‐Pb data (LA‐ICP‐MS and SIMS) from zircon from the Araguainha impact structure,Brazil

A silicious impact melt rock from polymict impact breccia of the northern part of the alkali granite core of the Araguainha impact structure, central Brazil, has been investigated. The melt rock is thought to represent a large mass of impact‐generated melt in suevite. In particular, a diverse population of zircon grains, with different impact‐induced microstructures, has been analyzed for U‐Pb isotopic systematics. Backscattered electron and cathodoluminescence images reveal heterogeneous intragrain domains with vesicular, granular, vesicular plus granular, and vesicular plus (presumably) baddeleyite textures, among others. The small likely baddeleyite inclusions are not only preferentially located along grain margins but also occur locally within grain interiors. LA‐ICP‐MS U‐Pb data from different domains yield lower intercept ages of 220, 240, and 260 Ma, a result difficult to reconcile with the previous “best age” estimate for the impact event at 254.7 ± 2.7 Ma. SIMS U‐Pb data, too, show a relatively large range of ages from 245 to 262 Ma. A subset of granular grains that yielded concordant SIMS ages were analyzed for crystallographic orientation by EBSD. Orientation mapping shows that this population consists of approximately micrometer‐sized neoblasts that preserve systematic orientation evidence for the former presence of the high‐pressure polymorph reidite. In one partially granular grain (#36), the neoblasts occur in linear arrays that likely represent former reidite lamellae. Such grains are referred to as FRIGN zircon. The best estimate for the age of the Araguainha impact event from our data set from a previously not analyzed type of impact melt rock is based on concordant SIMS data from FRIGN zircon grains. This age is 251.5 ± 2.9 Ma (2σ, MSWD = 0.45, p = 0.50, n = 4 analyses on three grains), indistinguishable from previous estimates based on zircon and monazite from other impact melt lithologies at Araguainha. Our work provides a new example of how FRIGN zircon can be combined with in situ U‐Pb geochronology to extract an accurate age for an impact event.     

Meso-scale effects of tropical deforestation in Amazonia: preparatory LBA modelling studies

As part of the preparation for the Large-Scale Biosphere Atmosphere Experiment in Amazonia, a meso-scale modelling study was executed to highlight deficiencies in the current understanding of land surface atmosphere interaction at local to sub-continental scales in the dry season. Meso-scale models were run in 1-D and 3-D mode for the area of Rondonia State, Brazil. The important conclusions are that without calibration it is difficult to model the energy partitioning of pasture; modelling that of forest is easier due to the absence of a strong moisture deficit signal. The simulation of the boundary layer above forest is good, above deforested areas (pasture) poor. The models’ underestimate of the temperature of the boundary layer is likely to be caused by the neglect of the radiative effects of aerosols caused by biomass burning, but other factors such as lack of sufficient entrainment in the model at the mixed layer top may also contribute. The Andes generate patterns of subsidence and gravity waves, the effects of which are felt far into the Rondonian area The results show that the picture presented by GCM modelling studies may need to be balanced by an increased understanding of what happens at the meso-scale. The results are used to identify key measurements for the LBA atmospheric meso-scale campaign needed to improve the model simulations. Similar modelling studies are proposed for the wet season in Rondonia, when convection plays a major role.     

On the treatment of uncertainty in seismic vulnerability and portfolio risk assessment

In a related study developed by the authors, building fragility is represented by intensity‐specific distributions of damage exceedance probability of various damage states. The contribution of the latter has been demonstrated in the context of loss estimation of building portfolios, where it is shown that the proposed concept of conditional fragility functions provides the link between seismic intensity and the uncertainty in damage exceedance probabilities. In the present study, this methodology is extended to the definition of building vulnerability, whereby vulnerability functions are characterized by hazard‐consistent distributions of damage ratio per level of primary seismic intensity parameter—Sa(T₁). The latter is further included in a loss assessment framework, in which the impact of variability and spatial correlation of damage ratio in the probabilistic evaluation of seismic loss is accounted for, using test‐bed portfolios of 2, 5, and 8‐story precode reinforced concrete buildings located in the district of Lisbon, Portugal. This methodology is evaluated in comparison with current state‐of‐the‐art methods of vulnerability and loss calculation, highlighting the discrepancies that can arise in loss estimates when the variability and spatial distributions of damage ratio, influenced by ground motion properties other than the considered primary intensity measure, are not taken into account.     

Multidimensional Investigation of Bedrock Heterogeneity/Unconformities at a DNAPL‐Impacted Site

Organic solvent (i.e., dense nonaqueous phase liquid, DNAPL) migration in the subsurface is known to be extremely sensitive to geologic heterogeneity. There is often a focus on heterogeneity that results from changing depositional conditions over short spatial scales. Similar or even more extreme spatial heterogeneity can result postdeposition due to erosional processes. This study applies a synergistic approach based on a combination of high‐resolution lithologic logs of continuous cores, borehole geophysical logs, surface electrical resistivity, and seismic refraction tomography models to assess spatial heterogeneity in a shallow bedrock sequence subject to multiple unconformities and contaminated with a mixture of organic chemicals. The persistence of DNAPL in the source zone and an associated dissolved‐phase plume led to variable impacts on formation resistivity across the study site. Seismic refraction in combination with electrical resistivity tomography improved interpretation of highly irregular erosional boundaries by delineating sharp lateral transitions in lithologic composition near the source zone and across the dissolved‐phase plume. Electrical resistivity was effective at differentiating between clean and mud‐rich sandstones and their unconformable contact with an underlying dolostone. Geophysical measurements revealed eroded dolostone mounds encased by a network of younger mud‐rich sandstones channelized by clean semi‐lithified sand, all of which was buried beneath variable glacial drift. Our synergistic multidimensional approach resulted in the development of a detailed three‐dimensional shallow bedrock geospatial model, which has led to an improved understanding of DNAPL migration and contaminant plume heterogeneity.