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The Bay of Málaga is located in a high biodiversity and productivity area that harbours a wide variety of commercial species exploited by different fishing fleets. Benthic and demersal fauna from circalittoral soft bottoms have been studied using a benthic dredge (BD) (8 sampling stations) and an otter trawl (OT) (8 sampling stations on a seasonal basis). Some sediment and water column variables, as well as the trawling activity, have also been studied and used for analysing their linkage with the fauna. A total of 287 species have been found in these bottoms and fish, molluscs and crustaceans represented the most diverse and abundant faunistic groups. A new record of the decapod Hippolyte leptometrae for Spanish waters is also included in this study. Some multivariate analyses using BD samples indicated the presence of three assemblages, but these seem to represent different facies of a single benthic community due to the absence of acute sediment changes and significant differences in the fauna. OT samples only displayed differences related to seasons but not to sediment types or depth. These seasonal differences seem to be linked to biological and ecological features of both dominant and/or commercial species. Mud and organic matter contents (%OM) in sediment, as well as the temperature, were the main variables linked to the spatial distribution of the benthic community identified with BD, whereas medium and coarse sand as well as gravel contents were the main variables linked to the changes of the epibenthic and demersal assemblage resulting from OT samples. The information of this study is of importance for improving the knowledge on the biodiversity of circalittoral soft bottoms of the Mediterranean and Alboran Sea as well as for the potential creation of a Marine Fisheries Reserve in the Bay of Málaga.
From simple averaging to more sophisticated registration and restoration strategies, such as super-resolution (SR), there exist different computational techniques that use a series of images of the same object to generate enhanced images where noise and other distortions have been reduced. In this work, we provide qualitative and quantitative measurements of this enhancement for high-angle annular dark-field scanning transmission electron microscopy imaging. These images are compared in two ways, qualitatively through visual inspection in real and reciprocal space, and quantitatively, through the calculation of objective measurements, such as signal-to-noise ratio and atom column roundness. Results show that these techniques improve the quality of the images. In this paper, we use an SR methodology that allows us to take advantage of the information present in the image frames and to reliably facilitate the analysis of more difficult regions of interest in experimental images, such as surfaces and interfaces. By acquiring a series of cross-sectional experimental images of magnetite (Fe3O4) thin films (111), we have generated interpolated images using averaging and SR, and reconstructed the atomic structure of the very top surface layer that consists of a full monolayer of Fe, with topmost Fe atoms in tetrahedrally coordinated sites.
This work presents the synthesis and characterization of TiO2 nanotubes (NTT) with chitosan (CS). In a first stage, electrochemical anodization of titanium foils was used to generate NTT in a membrane-type arrangement. From these experiments, suitable experimental conditions were selected. In a second stage, the synthesized NTT were detached from the titanium foils by sonication. In the third stage, the detached NTT were dispersed in an acid solution containing CS in various concentrations. Finally, the nanotubes-chitosan (NTT/CS) samples were characterized by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), and Fourier Transform Infrared Spectrometry (FTIR). Our results showed that the NTT presented very regular tube morphology with -OH and Ti-O- functional groups on the surface. The interaction of NTT and chitosan was enhanced by increasing the time of contact during the synthesis of the titanium composites.
Milk fat composition can be modulated by the inclusion of lipid supplements in ruminant diets. An interaction between the lipid supplement and the forage to concentrate ratio or the type of forage in the rations may affect milk fat composition. However, little is known about the effects of the starch-to-non-forage NDF ratio in the concentrate and lipid supplementation of goat diets. The aim of this work was to determine the role of dietary carbohydrates in goats rations supplemented with linseed oil on animal performance and milk fatty acid (FA) profile. A total of 16 dairy goats were allocated to two simultaneous experiments (two treatments each), in a crossover design with four animals per treatment and two experimental periods of 25 days. In both experiments alfalfa hay was the sole forage and the forage to concentrate ratio (33:67) remained constant. The concentrate in experiment 1 consisted of barley, maize and soybean meal (concentrate rich in starch), whereas it included soybean hulls replacing 25% of barley and 25% maize in experiment 2 (concentrate rich in NDF). As a result, the starch-to-non-forage NDF ratio was 3.1 in experiment 1 and it decreased to 0.8 in experiment 2. Both concentrates were administered either alone or in combination with 30 g/day of linseed oil. Animal performance parameters were not affected by experimental treatments. In contrast, major changes were observed in milk FA profile due to lipid supplementation and the type of concentrate. Linseed oil significantly raised vaccenic and rumenic acids as well as α-linolenic acid and its biohydrogenation intermediates while decreased medium-chain saturated FA (12:0 to 16:0) in milk fat. Milk fat contents of odd and branched-chain FA and trans-10 18:1 responded differently to linseed oil supplementation according to the concentrate fed.
In March 2011, a predator killed 33 hooded grebes, Podiceps gallardoi Rumboll (Podicipedidae), a critically endangered species, in a nesting colony at El Cervecero Lake, Santa Cruz Province, Argentina. The viscera of ten birds were examined for helminths. Two new species of Trematoda were recovered from the intestines. The plagiorchid Plagiorchis patagonensis n. sp. is mainly characterized by the larger size of the oral sucker relative to the ventral sucker, and by the distribution of the vitellarium in two lateral fields, confluent between the caecal bifurcation and the ventral sucker. The echinostomatid Euparyphium tobianum n. sp. is mainly characterized by possessing a head collar with 37–39 spines (4 angle spines on each ventral lappet, 4 lateral spines in a single row on each side, and 21–23 dorsal spines in a double row). An unidentified cestode, a tetramerid nematode and a notocotylid trematode were also recovered from the birds. This is the first record of helminths parasitizing the hooded grebe.
As part of further investigations into three linked haemorrhagic fever with renal syndrome (HFRS) cases in Wales and England, 21 rats from a breeding colony in Cherwell, and three rats from a household in Cheltenham were screened for hantavirus. Hantavirus RNA was detected in either the lungs and/or kidney of 17/21 (81%) of the Cherwell rats tested, higher than previously detected by blood testing alone (7/21, 33%), and in the kidneys of all three Cheltenham rats. The partial L gene sequences obtained from 10 of the Cherwell rats and the three Cheltenham rats were identical to each other and the previously reported UK Cherwell strain. Seoul hantavirus (SEOV) RNA was detected in the heart, kidney, lung, salivary gland and spleen (but not in the liver) of an individual rat from the Cherwell colony suspected of being the source of SEOV. Serum from 20/20 of the Cherwell rats and two associated HFRS cases had high levels of SEOV-specific antibodies (by virus neutralisation). The high prevalence of SEOV in both sites and the moderately severe disease in the pet rat owners suggest that SEOV in pet rats poses a greater public health risk than previously considered.
Radio astrometric campaigns using VLBI have provided distances and proper motions for masers associated with young massive stars (BeSSeL survey). The ongoing BAaDE project plans to obtain astrometric information of SiO maser stars located in the inner Galaxy. These stars are associated with evolved, mass-losing stars. By overlapping optical (Gaia), infrared (2MASS, MSX and WISE) and radio (BAaDE) sources, we expect to obtain important clues on the intrinsic properties and population distribution of late-type stars. Moreover, a comparison of the Galactic parameters obtained with Gaia and VLBI can be done using radio observations on different targets: young massive stars (BeSSeL) and evolved stars (BAaDE).
The astrometric capability of the Hubble Space Telescope Planetary Camera (WF/PC1) is investigated, motivated by a study of the internal velocity distribution of globular clusters. The astrometric accuracy of the HST PC will be determined ultimately by 1) the accuracy to which the aberrated images can be ‘centered’, and 2) the accuracy to which the distortions across the PC field can be modeled. A series of overlapping exposures of two clusters, NGC 6752 and M15, are utilized to examine these issues.
We have made use of maximum-likelihood image reconstruction to address the first issue, with good success. Reconstruction improves both the detectability and precision of the image centers. A preliminary exploration of the second issue, that of modeling the distortion across the PC field, is also presented, using positions derived from the multiple overlapping exposures.
Using the VLBA, the BeSSeL survey has provided distances and proper motions of young massive stars, allowing an accurate measure of the Galactic spiral structure. By the same technique, we are planning to map the inner Galaxy using positions and velocities of evolved stars (provided by the BAaDE survey). These radio astrometric measurements (BeSSeL and BAaDE) will be complementary to Gaia results and the overlap will provide important clues on the intrinsic properties and population distribution of the stars in the bulge.
The Bulge Asymmetries and Dynamical Evolution (BAaDE) survey will provide positions and line-of-sight velocities of ~20, 000 evolved, maser bearing stars in the Galactic plane. Although this Galactic region is affected by optical extinction, BAaDE targets may have Gaia cross-matches, eventually providing additional stellar information. In an initial attempt to cross-match BAaDE targets with Gaia, we have found more than 5,000 candidates. Of these, we may expect half to show SiO emission, which will allow us to obtain velocity information. The cross-match is being refined to avoid false positives using different criteria based on distance analysis, flux variability, and color assessment in the mid- and near-IR. Once the cross-matches can be confirmed, we will have a unique sample to characterize the stellar population of evolved stars in the Galactic bulge, which can be considered fossils of the Milky Way formation.
Strong winds from massive stars are a topic of interest to a wide range of astrophysical fields. In High-Mass X-ray Binaries the presence of an accreting compact object on the one side allows to infer wind parameters from studies of the varying properties of the emitted X-rays; but on the other side the accretor’s gravity and ionizing radiation can strongly influence the wind flow. Based on a collaborative effort of astronomers both from the stellar wind and the X-ray community, this presentation attempts to review our current state of knowledge and indicate avenues for future progress.
Self-determination theory has shown that autonomy support in the classroom is associated with an increase of students’ intrinsic motivation. Moreover, intrinsic motivation is related with positive outcomes. This study examines the relationships between autonomy support, intrinsic motivation to learn and two motivational consequences, deep learning and vitality. Specifically, the hypotheses were that autonomy support predicts the two types of consequences, and that autonomy support directly and indirectly predicts the vitality and the deep learning through intrinsic motivation to learn. Participants were 276 undergraduate students. The mean age was 21.80 years (SD = 2.94). Structural equation modeling was used to test the relationships between variables and delta method was used to analyze the mediating effect of intrinsic motivation to learn. Results indicated that student perception of autonomy support had a positive effect on deep learning and vitality (p < .001). In addition, these associations were mediated by intrinsic motivation to learn. These findings suggest that teachers are key elements in generating of autonomy support environment to promote intrinsic motivation, deep learning, and vitality in classroom. Educational implications are discussed.
δ Sct stars are among the most promising targets to perform ground-based asteroseismology. High resolution spectroscopy offers us a powerful technique to identify radial and nonradial pulsation modes, since we can easily detect oscillations and travelling features in the line profiles.
Diet influences animal body and tissue composition due to direct deposition and to the nutrients effects on metabolism. The influence of specific nutrients on the molecular regulation of lipogenesis is not well characterized and is known to be influenced by many factors including timing and physiological status. A trial was performed to study the effects of different dietary energy sources on lipogenic genes transcription in ham adipose tissue of Iberian pigs, at different growth periods and on feeding/fasting situations. A total of 27 Iberian male pigs of 28 kg BW were allocated to two separate groups and fed with different isocaloric feeding regimens: standard diet with carbohydrates as energy source (CH) or diet enriched with high oleic sunflower oil (HO). Ham subcutaneous adipose tissue was sampled by biopsy at growing (44 kg mean BW) and finishing (100 kg mean BW) periods. The first sampling was performed on fasted animals, while the last sampling was performed twice, with animals fasted overnight and 3 h after refeeding. Effects of diet, growth period and feeding/fasting status on gene expression were explored quantifying the expression of a panel of key genes implicated in lipogenesis and lipid metabolism processes. Quantitative PCR revealed several differentially expressed genes according to diet, with similar results at both timings: RXRG, LEP and FABP5 genes were upregulated in HO group while ME1, FASN, ACACA and ELOVL6 were upregulated in CH. The diet effect on ME1 gene expression was conditional on feeding/fasting status, with the higher ME1 gene expression in CH than HO groups, observed only in fasting samples. Results are compatible with a higher de novo endogenous synthesis of fatty acids (FA) in the carbohydrate-supplemented group and a higher FA transport in the oleic acid-supplemented group. Growth period significantly affected the expression of most of the studied genes, with all but PPARG showing higher expression in finishing pigs according to a pattern dissimilar from the usual in cosmopolitan pig breeds. Feeding/fasting status only influenced PPARG gene transcription. The lack of effects of feeding/fasting status on lipogenic gene expression and the higher ME1 response to diet in fasting samples than in postprandial sampling, suggest the persistence of de novo lipogenesis during fasting. Overall results improve the understanding of the influence of different factors on lipid metabolism regulation in Iberian pigs.
Visual stress (VS) affects reading in 5–12% of the general population and 31–36% of children with reading disorders. Symptoms include print distortions and visual discomfort when reading, and are exacerbated by fluorescent lighting. Prior research has indicated that VS can also affect proficient readers. We therefore examined levels of visual discomfort in a group of expert readers (n = 24) under both standard and spectrally-filtered fluorescent lighting. Participants rated their awareness of six symptoms of VS under each lighting condition. Under the standard condition, 4(16.7%) of the group recorded moderate to high levels of VS. Differences in symptom levels and reading speed between conditions were analysed using the Wilcoxon Signed Rank Test. Under the filter condition, the group reported less discomfort regarding all six symptoms of VS surveyed. The differences were significant with respect to three of the symptoms (p = .029 - p < .001), with a medium effect size in all of them (r = .31 - r = .46) and total score (p = .007; r = .39). Variations in reading proficiency included significantly fewer self-corrections (p = .019) and total errors (p = .004). Here we present evidence that VS-type symptoms of reading discomfort are not confined to populations with reading difficulties and may also occur in proficient readers, and that simple adaptations to fluorescent lighting may alleviate such symptoms.
Stellar clusters are crucial in the study of a variety of topics including the star formation process, stellar nucleosynthesis and evolution, dynamical interaction among stars, or the assembly and evolution of galaxies. In particular, Open Clusters (OCs) have been widely used to constrain the formation and evolution of the Milky Way disc. They provide information about the chemical patterns and the existence of radial and vertical gradients or an age-metallicity relation. However, all these investigations are hampered by the fact that only a small fraction of clusters have been studied homogeneously. Galactic surveys performed from the ground such as the Apache Point Observatory Galactic Evolution Experiment (APOGEE), the Gaia-ESO Survey (GES), or the GALactic Archaeology with HERMES (GALAH) include OCs among their targets. OCs are also sampled from the space by the Gaia and Kepler missions.
The OCCASO goal is to derive abundances for more than 20 chemical species in at least 6 Red Clump stars in ∼30 Northern hemisphere OCs. In order to ensure the reliability of the derived chemical abundances, these are derived using different analysis techniques similar to what is being performed by GES.
One of the OCCASO requirements is the homogeneity between instruments, methods and model atmospheres used, and in the same scale than the GES-UVES abundances. For this reason we are performing different tests checking internal and external consistency. Derived stellar atmosphere parameters and Fe abundances will be published in the first data release scheduled for the first semester of 2015.
Relationships between fatty acids (FAs) in plant oils included in goat diets and milk fat C18 isomers were determined by Principal Factor Analysis (PFA). The three first principal factors (PF1, PF2 and PF3) accounted for 64·5% of the total variation in milk FAs contents. Fatty acids with a double bond at carbons 13, 14, 15 or 16 had high (>0·6) and positive loadings for PF1, trans-4 to trans-8 C18:1 for PF2, whereas trans-10 C18:1, trans-11 C18:1 and cis-9 trans-11 C18:2 showed high and positive loadings for PF3. Pearson's correlations supported that PF1, PF2 and PF3 were related to α-linolenic, oleic and linoleic acid intakes, respectively. Our results show that the quantitatively main FAs in plant lipids supplemented to dairy ruminants are often the main cause of the observed changes in milk C18 isomer contents. However, sometimes the observed changes are caused, or at least are influenced, by other FAs present in lower quantities in the plant lipids. Thus, using mixtures of plant oils with differently unsaturated main FAs could be a way of tailoring milk fat composition to a pre-designed pattern.
CHD may ensue from chronic systemic low-grade inflammation. Diet is a modifiable risk factor for both, and its optimisation may reduce post-operative mortality, atrial fibrillation and cognitive decline. In the present study, we investigated the usual dietary intakes of patients undergoing elective coronary artery bypass grafting (CABG), emphasising on food groups and nutrients with putative roles in the inflammatory/anti-inflammatory balance. From November 2012 to April 2013, we approached ninety-three consecutive patients (80 % men) undergoing elective CABG. Of these, fifty-five were finally included (84 % men, median age 69 years; range 46–84 years). The median BMI was 27 (range 18–36) kg/m2. The dietary intake items were fruits (median 181 g/d; range 0–433 g/d), vegetables (median 115 g/d; range 0–303 g/d), dietary fibre (median 22 g/d; range 9–45 g/d), EPA+DHA (median 0·14 g/d; range 0·01–1·06 g/d), vitamin D (median 4·9 μg/d; range 1·9–11·2 μg/d), saturated fat (median 13·1 % of energy (E%); range 9–23 E%) and linoleic acid (LA; median 6·3 E%; range 1·9–11·3 E%). The percentages of patients with dietary intakes below recommendations were 62 % (fruits; recommendation 200 g/d), 87 % (vegetables; recommendation 150–200 g/d), 73 % (dietary fibre; recommendation 30–45 g/d), 91 % (EPA+DHA; recommendation 0·45 g/d), 98 % (vitamin D; recommendation 10–20 μg/d) and 13 % (LA; recommendation 5–10 E%). The percentages of patients with dietary intakes above recommendations were 95 % (saturated fat; recommendation < 10 E%) and 7 % (LA). The dietary intakes of patients proved comparable with the average nutritional intake of the age- and sex-matched healthy Dutch population. These unbalanced pre-operative diets may put them at risk of unfavourable surgical outcomes, since they promote a pro-inflammatory state. We conclude that there is an urgent need for intervention trials aiming at rapid improvement of their diets to reduce peri-operative risks.
To predict the likelihood of hospital-onset Clostridium difficile infection (HO-CDI) based on patient clinical presentations at admission
Retrospective data analysis
Six US acute care hospitals
We used clinical data collected at the time of admission in electronic health record (EHR) systems to develop and validate a HO-CDI predictive model. The outcome measure was HO-CDI cases identified by a nonduplicate positive C. difficile toxin assay result with stool specimens collected >48 hours after inpatient admission. We fit a logistic regression model to predict the risk of HO-CDI. We validated the model using 1,000 bootstrap simulations.
Among 78,080 adult admissions, 323 HO-CDI cases were identified (ie, a rate of 4.1 per 1,000 admissions). The logistic regression model yielded 14 independent predictors, including hospital community onset CDI pressure, patient age ≥65, previous healthcare exposures, CDI in previous admission, admission to the intensive care unit, albumin ≤3 g/dL, creatinine >2.0 mg/dL, bands >32%, platelets ≤150 or >420 109/L, and white blood cell count >11,000 mm3. The model had a c-statistic of 0.78 (95% confidence interval [CI], 0.76–0.81) with good calibration. Among 79% of patients with risk scores of 0–7, 19 HO-CDIs occurred per 10,000 admissions; for patients with risk scores >20, 623 HO-CDIs occurred per 10,000 admissions (P<.0001).
Using clinical parameters available at the time of admission, this HO-CDI model demonstrated good predictive ability, and it may have utility as an early risk identification tool for HO-CDI preventive interventions and outcome comparisons.