A generalized viscosity equation of state including a single adjustable parameter for correlating and estimating the viscosity of ionic liquids at different temperatures and pressures is proposed. ...The similar shape and form of the curves (isotherms and saturation lines) observed in a density-pressure-temperature plot and in a viscosity-pressure-temperature plot (ρTP and μTP plots), known as geometrical similitude, is the basis of the proposed model. Viscosity data available in the literature has been gathered, analyzed, and selected to finally construct a database of consistent data to obtain a general model. The generalized equation of state model includes a number of parameters that are determined by fitting the model using the selected experimental viscosity data of different types of ionic liquids. In total, 3857 viscosity data for 187 ionic liquids in the temperature range of 253–573 K and pressures from 1.0 up to 1500 bar have been considered. The generalized viscosity model has been compared with other existing approaches and results show that the new viscosity cubic equation of state model provides accurate and consistent results taking in account the simplicity of the generalized expressions, which contains only one adjustable parameter for each ionic liquid.
Stable isotopes of carbon and nitrogen were used to test the hypothesis that stomach content analysis has systematically overlooked the consumption of gelatinous zooplankton by pelagic mesopredators ...and apex predators. The results strongly supported a major role of gelatinous plankton in the diet of bluefin tuna (Thunnus thynnus), little tunny (Euthynnus alletteratus), spearfish (Tetrapturus belone) and swordfish (Xiphias gladius). Loggerhead sea turtles (Caretta caretta) in the oceanic stage and ocean sunfish (Mola mola) also primarily relied on gelatinous zooplankton. In contrast, stable isotope ratios ruled out any relevant consumption of gelatinous plankton by bluefish (Pomatomus saltatrix), blue shark (Prionace glauca), leerfish (Lichia amia), bonito (Sarda sarda), striped dolphin (Stenella caerueloalba) and loggerhead sea turtles (Caretta caretta) in the neritic stage, all of which primarily relied on fish and squid. Fin whales (Balaenoptera physalus) were confirmed as crustacean consumers. The ratios of stable isotopes in albacore (Thunnus alalunga), amberjack (Seriola dumerili), blue butterfish (Stromaeus fiatola), bullet tuna (Auxis rochei), dolphinfish (Coryphaena hyppurus), horse mackerel (Trachurus trachurus), mackerel (Scomber scombrus) and pompano (Trachinotus ovatus) were consistent with mixed diets revealed by stomach content analysis, including nekton and crustaceans, but the consumption of gelatinous plankton could not be ruled out completely. In conclusion, the jellyvorous guild in the Mediterranean integrates two specialists (ocean sunfish and loggerhead sea turtles in the oceanic stage) and several opportunists (bluefin tuna, little tunny, spearfish, swordfish and, perhaps, blue butterfish), most of them with shrinking populations due to overfishing.
Summary
The development of a seedling into a photosynthetically active plant is a crucial process. Despite its importance, we do not fully understand the regulatory mechanisms behind the ...establishment of functional chloroplasts.
We herein provide new insight into the early light response by identifying the function of three basic region/leucine zipper (bZIP) transcription factors: bZIP16, bZIP68, and GBF1. These proteins are involved in the regulation of key components required for the establishment of photosynthetically active chloroplasts. The activity of these bZIPs is dependent on the redox status of a conserved cysteine residue, which provides a mechanism to finetune light‐responsive gene expression.
The blue light cryptochrome (CRY) photoreceptors provide one of the major light‐signaling pathways, and bZIP target genes overlap with one‐third of CRY‐regulated genes with an enrichment for photosynthesis/chloroplast‐associated genes. bZIP16, bZIP68, and GBF1 were demonstrated as novel interaction partners of CRY1. The interaction between CRY1 and bZIP16 was stimulated by blue light. Furthermore, we demonstrate a genetic link between the bZIP proteins and cryptochromes as the cry1cry2 mutant is epistatic to the cry1cry2bzip16bzip68gbf1 mutant.
bZIP16, bZIP68, and GBF1 regulate a subset of photosynthesis associated genes in response to blue light critical for a proper greening process in Arabidopsis.
In this work, a model for the thermal conductivity of nonpolar and polar substances is developed based on the geometric similitude concept between the P–v (molar volume)–-T and T–k (thermal ...conductivity)–-P plots. The Redlich–Kwong equation of state is used to perform the geometric similitude. The parameters of the model are estimated by fitting experimental data of saturated liquid and saturated vapor. Generalized expressions in terms of the normal boiling point are proposed for the parameters of n-alkanes and n-alcohols. The calculated average absolute deviations are 7.63 and 8.55%, respectively, for the n-alkanes and the n-alcohols used to develop the generalized expressions. Also, some predictive calculations are performed, and deviations below 10.62 and 9.42% are obtained for n-alkanes and n-alcohols, respectively. In total, 2412 experimental data (952 correlated data and 1460 predicted data) in the temperature range of 95– to 645.5 K and pressures below 906.4 bar have been considered. The empirical model has been extended to binary and ternary mixtures using several approaches. In total, 16 mixtures in the temperature range between 287.55 and 345.48 K at 1.01 bar are evaluated. The deviations are below 4.63% when one binary interaction parameter is used. In general, the results indicate that the empirical model is simpler than the other models reported in the literature and generates adequate results.
The threats posed by floating marine macro-litter (FMML) of anthropogenic origin to the marine fauna, and marine ecosystems in general, are universally recognized. Dedicated monitoring programmes and ...mitigation measures are in place to address this issue worldwide, with the increasing support of new technologies and the automation of analytical processes. In the current study, we developed algorithms capable of detecting and quantifying FMML in aerial images, and a web-oriented application that allows users to identify FMML within images of the sea surface. The proposed algorithm is based on a deep learning approach that uses convolutional neural networks (CNNs) capable of learning from unstructured or unlabelled data. The CNN-based deep learning model was trained and tested using 3723 aerial images (50% containing FMML, 50% without FMML) taken by drones and aircraft over the waters of the NW Mediterranean Sea. The accuracies of image classification (performed using all the images for training and testing the model) and cross-validation (performed using 90% of images for training and 10% for testing) were 0.85 and 0.81, respectively. The Shiny package of R was then used to develop a user-friendly application to identify and quantify FMML within the aerial images. The implementation of this, and similar algorithms, allows streamlining substantially the detection and quantification of FMML, providing support to the monitoring and assessment of this environmental threat. However, the automated monitoring of FMML in the open sea still represents a technological challenge, and further research is needed to improve the accuracy of current algorithms.
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•We developed deep learning models to detect floating marine litter in aerial images.•Models were trained with over 3700 images taken during drone and aircraft surveys.•The best model accuracy was 0.81 during cross-validation.•A CNN model was implemented in an application based on the “Shiny” package.•The app’ allows detecting and quantifying marine litter in the uploaded aerial images.
The aim of the present study was twofold: (i) to validate the drone methodology for floating marine macro-litter (FMML) monitoring, by comparing the results obtained through concurrent drone surveys ...and visual observations from vessels, and (ii) to assess FMML densities along the North Western Mediterranean Sea using the validated drone surveys. The comparison between monitoring techniques was performed based on 18 concurrent drone/vessel transects. Similar densities of FMML were detected through the two methods (16 items km−2 from the drone method vs 19 items km−2 from the vessel-based visual method). The assessment of FMML densities was done using 40 additional drone transects performed over the waters off the Catalan coast. The densities of FMML observed ranged 0–200 items km−2. These results provide a validation of the use of drones to monitor FMML and contribute to increasing the knowledge about the density of FMML in the North Western Mediterranean Sea.
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•We compared results from concurrent visual and drone surveys.•The two methods proved equally effective to detect floating marine macro-litter.•We used the drone method to monitor marine litter along the Catalan coast.•We detected densities up to 200 items km−2 in the area off the city of Barcelona.•These results encourage using the drone method to monitor marine litter.
The colonisation of new suitable habitats is crucial for species survival at evolutionary scale under changing environmental conditions. However, colonisation potential may be limited by philopatry ...that facilitates exploiting successful habitats across generations. We examine the mechanisms of long distance dispersal of the philopatric loggerhead sea turtle (Caretta caretta) by analysing 40 sporadic nesting events in the western Mediterranean. The analysis of a fragment of the mitochondrial DNA and 7 microsatellites of 121 samples from 18 of these nesting events revealed that these nests were colonising events associated with juveniles from distant populations feeding in nearby foraging grounds. Considering the temperature-dependent sex determination of the species, we simulated the effect of the incubation temperature and propagule pressure on a potential colonisation scenario. Our results indicated that colonisation will succeed if warm temperature conditions, already existing in some of the beaches in the area, extend to the whole western Mediterranean. We hypothesize that the sporadic nesting events in developmental foraging grounds may be a mechanism to overcome philopatry limitations thus increasing the dispersal capabilities of the species and the adaptability to changing environments. Sporadic nesting in the western Mediterranean can be viewed as potential new populations in a scenario of rising temperatures.
In this work, a semitheoretical model based on the momentum transport theory is generalized through the development of a group contribution method. Viscosity data for temperatures between 13.95 and ...950 K and pressures from 1.00 × 10–3 bar up to 1.00 × 104 bar were used to develop and to validate the model. To perform viscosity calculations, the model requires density and residual enthalpy that were obtained from a modified Peng–Robinson equation of state. Also, the model has one adjustable parameter that can be estimated form the group contribution method. Viscosity was calculated for 256 substances including 95 non-polar and 161 polar compounds. In total, 23 organic families were considered. Average deviations below 6.67% were calculated. The performance of the model was compared with those of other models reported in the literature. Calculations were carried out to include the saturation and single-phase regions. In general, it can be considered that the proposed model describes viscosity adequately using only one adjustable parameter.
A simple computer tool based on MS Excel for estimating several physical, transport, and thermodynamic properties is presented. The properties included in the software are critical properties (T c, P ...c, V c, and Z c), normal boiling temperature, acentric factor, density, heat capacity, thermal conductivity, viscosity, surface tension, speed of sound, melting temperature, and heat of melting. Different types of models previously proposed by the authors are used and the limitations of each model are clearly stated. These models include group contributions, semiempirical correlations, equations of state, and the geometric similitude equation of state concept. The calculations provided by the software do not aim to replace experimental data but help in obtaining a good estimate before going to the lab to experimentally measure a given property. The software is available free of charge and can be modified for particular applications.
Individual specialization in vertebrates is often related to morphological variability, but can also reflect a diversity of trajectories during the learning sensitive period in early life. In both ...cases the capacity of adults to adapt to new environments can be limited if further morphological or behavioral change is not possible. Adult loggerhead turtles Caretta caretta (Linnaeus, 1758) from Cape Verde (NW Africa) may forage in the open ocean or on the continental shelf. Oceanic foragers prevail in the population, but neritic foragers grow larger, have a higher reproductive output and produce best fitted offspring. Previous research suggests that the high prevalence of oceanic foragers is because the migratory routes followed by juvenile turtles during their early life results into a low probability of settlement on the African shelf. The stable isotope ratios of C and N in 60μm carapace layers from 14 adult females have been analyzed to reconstruct retrospectively their individual habitat use patterns and test the hypothesis that adult loggerhead turtles remain faithful to their foraging grounds even if sub-optimal. Only two turtles exhibited clear oceanic—neritic shifts, approximately 22 and 15years before sampling. The remaining turtles had foraged in neritic (3) or oceanic (9) habitat as long as recorded in the carapace scutes (approximately 8–37years), despite the smaller body size and the lower reproductive output associated to oceanic foraging. These results suggest that habitat shifts during adulthood are unlikely in this species and support the hypothesis that only during the juvenile stage loggerhead turtles are flexible enough to adapt to contrasting environments.
•Adult marine turtles exhibit high levels of individual specialization on habitat use.•Heterogeneity in reproductive output is strongly liked to foraging ground quality.•Stable isotope analysis allows reconstructing individual foraging trajectories.•Most females do not shift habitats as adults despite low fitness.•Adult marine turtles have a low behavioral plasticity once specialized.
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