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Timing is everything: Drivers of interannual variability in blue whale migration.
Blue whales need to time their migration from their breeding grounds to their feeding grounds to avoid missing peak prey abundances, but the cues they use for this are unknown. We examine migration timing (inferred from the local onset and cessation of blue whale calls recorded on seafloor-mounted hydrophones), environmental conditions (e.g., sea surface temperature anomalies and chlorophyll a), and prey (spring krill biomass from annual net tow surveys) during a 10 year period (2008-2017) in waters of the Southern California Region where blue whales feed in the summer. Colder sea surface temperature anomalies the previous season were correlated with greater krill biomass the following year, and earlier arrival by blue whales. Our results demonstrate a plastic response of blue whales to interannual variability and the importance of krill as a driving force behind migration timing. A decadal-scale increase in temperature due to climate change has led to blue whales extending their overall time in Southern California. By the end of our 10-year study, whales were arriving at the feeding grounds more than one month earlier, while their departure date did not change. Conservation strategies will need to account for increased anthropogenic threats resulting from longer times at the feeding grounds
Social immunity of the family: parental contributions to a public good modulated by brood size.
Social immunity refers to any immune defence that benefits others, besides the individual that mounts the response. Since contributions to social immunity are known to be personally costly, they are contributions to a public good. However, individuals vary in their contributions to this public good and it is unclear why. Here we investigate whether they are responding to contributions made by others with experiments on burying beetle (Nicrophorus vespilloides) families. In this species, females, males and larvae each contribute to social immunity through the application of antimicrobial exudates upon the carrion breeding resource. We show experimentally that mothers reduce their contributions to social immunity when raising large broods, and test two contrasting hypotheses to explain why. Either mothers are treating social immunity as a public good, investing less in social immunity when their offspring collectively contribute more, or mothers are trading off investment in social immunity with investment in parental care. Overall, our experiments yield no evidence to support the existence of a trade-off between social immunity and other parental care traits: we found no evidence of a trade-off in terms of time allocated to each activity, nor did the relationship between social immunity and brood size change with female condition. Instead, and consistent with predictions from models of public goods games, we found that higher quality mothers contributed more to social immunity. Therefore our results suggest that mothers are playing a public goods game with their offspring to determine their personal contribution to the defence of the carrion breeding resource.AD was supported by NERC grant NE/H019731/1 to RMK. ODeG was supported by the Cambridge Trust and the Mexican Council for Science and Technology (CONACyT). RMK was supported in part by ERC Consolidators grant 310785 BALDWINIAN_BEETLES. SCC was supported by a NERC fellowship (NE/H014225/2), CER was supported by a Department for Employment and Learning PhD studentship. We thank A. Backhouse for help in maintaining the burying beetle population. We thank two anonymous reviewers for helpful comments on the manuscript.This is the final version of the article. It was first available from Springer via http://dx.doi.org/10.1007/s10682-015-9806-
The cohesin ring concatenates sister DNA molecules
Sister chromatid cohesion, which is essential for mitosis, is mediated by a multi-subunit
protein complex called cohesin whose Scc1, Smc1, and Smc3 subunits form a tripartite
ring structure. It has been proposed that cohesin holds sister DNAs together by trapping
them inside its ring. To test this, we used site-specific cross-linking to create chemical
connections at the three interfaces between the ringâs three constituent polypeptides,
thereby creating covalently closed cohesin rings. As predicted by the ring entrapment
model, this procedure produces dimeric DNA/cohesin structures that are resistant to
protein denaturation. We conclude that cohesin rings concatenate individual sister
minichromosome DNAs
Study of alkaline hydrothermal activation of belite cements by thermal analysis
The effect of alkaline hydrothermal activation of class-C fly ash belite cement was studied using thermal analysis (TG/DTG) by determining the increase in the combined water during a period of hydration of 180 days. The results were compared with those obtained for a belite cement hydrothermally activated in water. The two belite cements were fabricated via the hydrothermal-calcination route of class-C fly ash in 1 M NaOH solution (FABC-2-N) or demineralised water (FABC-2-W). From the results, the effect of the alkaline hydrothermal activation of belite cement (FABC-2-N) was clearly differentiated, mainly at early ages of hydration, for which the increase in the combined water was markedly higher than that of the belite cement that was hydrothermally activated in water. Important direct quantitative correlations were obtained among physicochemical parameters, such as the combined water, the BET surface area, the volume of nano-pores, and macro structural engineering properties such as the compressive mechanical strength
Quantitative study of hydration of C3S and C2S by thermal analysis. Evolution and composition of C-S-H gels formed
This research is part of a European project (namely, CODICE project), main objective of which is modelling, at a multi-scale, the evolution of the mechanical performance of non-degraded and degraded cementitious matrices. For that, a series of experiments were planned with pure synthetic tri-calcium silicate (C3S) and bi-calcium silicate (C2S) (main components of the Portland cement clinker) to obtain different calciumâsilicateâhydrate (CâSâH) gel structures during their hydration. The characterization of those CâSâH gels and matrices will provide experimental parameters for the validation of the multi-scale modelling scheme proposed. In this article, a quantitative method, based on thermal analyses, has been used for the determination of the chemical composition of the CâSâH gel together with the degree of hydration and quantitative evolution of all the components of the pastes. Besides, the microstructure and type of silicate tetrahedron and mean chain length (MCL) were studied by scanning electron microscopy (SEM) and 29Si magic-angle-spinning (MAS) NMR, respectively. The main results showed that the chemical compositions for the CâSâH gels have a CaO/SiO2 M ratio almost constant of 1.7 for both C3S and C2S compounds. Small differences were found in the gel water content: the H2O/SiO2 M ratio ranged from 2.9 ± 0.2 to 2.6 ± 0.2 for the C3S (decrease) and from 2.4 ± 0.2 to 3.2 ± 0.2 for the C2S (increase). The MCL values of the CâSâH gels, determined from 29Si MAS NMR, were 3.5 and 4 silicate tetrahedron, for the hydrated C3S and C2S, respectively, remaining almost constant at all hydration periods
Paradoxical effects of Worrisome Thoughts Suppression: the influence of depressive mood
Thought suppression increases the persistence of unwanted idiosyncratic worries
thoughts when individuals try to suppress them. The failure of suppression may
contribute to the development and maintenance of emotional disorders. Depressive
people seem particulary prone to engage in unsuccessful mental control strategies such
as thought suppression. Worry has been reported to be elevated in depressed individuals
and a dysphoric mood may also contribute for the failure of suppression. No studies
examine, however, the suppression of worisome thoughts in individuals with depressive
symptoms. To investigate the suppression effects of worrisome thoughts, 46
participants were selected according to the cut-off score of a depressive
symptomatology scale and they were divided in two groups (subclinical and nonclinical
group). All the individuals took part in an experimental paradigm of thought
suppression. The results of the mixed factorial analysis of variance revealed an
increased frequency of worrisome thoughts during the suppression phase on depending
of the depressive symptoms. These findings confirm that depressive mood can reduce
the success of suppression.info:eu-repo/semantics/publishedVersio
AGUIA: autonomous graphical user interface assembly for clinical trials semantic data services
<p>Abstract</p> <p>Background</p> <p>AGUIA is a front-end web application originally developed to manage clinical, demographic and biomolecular patient data collected during clinical trials at MD Anderson Cancer Center. The diversity of methods involved in patient screening and sample processing generates a variety of data types that require a resource-oriented architecture to capture the associations between the heterogeneous data elements. AGUIA uses a semantic web formalism, resource description framework (RDF), and a bottom-up design of knowledge bases that employ the S3DB tool as the starting point for the client's interface assembly.</p> <p>Methods</p> <p>The data web service, S3DB, meets the necessary requirements of generating the RDF and of explicitly distinguishing the description of the domain from its instantiation, while allowing for continuous editing of both. Furthermore, it uses an HTTP-REST protocol, has a SPARQL endpoint, and has open source availability in the public domain, which facilitates the development and dissemination of this application. However, S3DB alone does not address the issue of representing content in a form that makes sense for domain experts.</p> <p>Results</p> <p>We identified an autonomous set of descriptors, the GBox, that provides user and domain specifications for the graphical user interface. This was achieved by identifying a formalism that makes use of an RDF schema to enable the automatic assembly of graphical user interfaces in a meaningful manner while using only resources native to the client web browser (JavaScript interpreter, document object model). We defined a generalized RDF model such that changes in the graphic descriptors are automatically and immediately (locally) reflected into the configuration of the client's interface application.</p> <p>Conclusions</p> <p>The design patterns identified for the GBox benefit from and reflect the specific requirements of interacting with data generated by clinical trials, and they contain clues for a general purpose solution to the challenge of having interfaces automatically assembled for multiple and volatile views of a domain. By coding AGUIA in JavaScript, for which all browsers include a native interpreter, a solution was found that assembles interfaces that are meaningful to the particular user, and which are also ubiquitous and lightweight, allowing the computational load to be carried by the client's machine.</p
Some Like It Fat: Comparative Ultrastructure of the Embryo in Two Demosponges of the Genus Mycale (Order Poecilosclerida) from Antarctica and the Caribbean
0000-0002-7993-1523© 2015 Riesgo et al. This is an open access article distributed under the terms of the Creative Commons Attribution License [4.0], which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article
The D allele of angiotensin-converting enzyme gene is associated with greater hemodynamic response to resistance exercises
HYPOTHESIS/INTRODUCTION: The association of ACE I/D polymorphism and hemodynamic response to exercise have been limited to primarily aerobic exercises. We hypothesized that D allele carriers would show greater hemodynamic response to resistance exercise, as has been observed with aerobic. This study aimed to investigate the association of ACE I/D polymorphism and hemodynamic (blood pressure (BP), heart rate (HR) and rate-pressure product (RPP)) response to resistance exercise in young healthy subjects.MATERIALS AND METHODS: ACE I/D polymorphisms were studied by PCR analysis from 75 healthy men. Subjects completed a resistance exercise session of three sets of 10 knee extension repetitions with loads of 50, 75 and 100% of 10RM and two-minute rest intervals. Hemodynamic measures were recorded before and immediately after each set. Analysis of variance was used to identify significant differences among ACE genotypes. RESULTS: ACE I/D polymorphism is associated with hemodynamic response to resistance exercise, as healthy subjects with ACE D allele were prone to higher responses. In addition, this phenotypic difference seems to be a load-dependent trend. CONCLUSION: ACE DD carriers exhibit greater heart work during resistance exercise. Future studies should focus on the influence of resistance training period with different workloads on the hemodynamic response in healthy individuals with different ACE genotypes
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