11,785 research outputs found

    The positivity effect in older adults : the role of affective interference and inhibition

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    Objectives: Research shows that aging often involves a decrease in the experience of negative affect and might even be associated with a stabilization or an increase in experience concerning positive affect. As it has been suggested that these changes could be related to the processing of emotional information, the aim of this study was to investigate interference and inhibition toward sad and happy faces in healthy elderly people compared to a younger population. Method: We used an affective modification of the negative priming task. If interference is related to enhanced inhibition, reduced interference from negative stimuli and a related weakened inhibition toward negative stimuli in the elderly group would be in line with the positivity hypothesis. Results: As expected, the results indicated that interference from negative stimuli was significantly lower in older adults as compared to younger adults, whereas this was not the case for positive stimuli. Moreover, at inhibitory level a significantly reduced processing of negative stimuli was observed only in the older adult group, whereas there was no such effect in the case of positive material. Conclusion: These observations are indicative for a decreased negative bias in older adults at information processing level. This provides new insights with regard to age-related differences in emotion processing

    Orbital structure of triaxial galaxies

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    We have developed a method to construct realistic triaxial dynamical models for elliptical galaxies, allowing us to derive best-fitting parameters, such as the mass-to-light ratio and the black hole mass, and to study the orbital structure. We use triaxial theoretical Abel models to investigate the robustness of the method.Comment: 2 pages (1 figure), to appear in the proceedings of the IAU Symposium 220 "Dark matter in galaxies", eds. S. Ryder, D.J. Pisano, M. Walker and K. Freema

    How to perform RT-qPCR accurately in plant species?: a case study on flower colour gene expression in an azalea (Rhododendron simsii hybrids) mapping population

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    Background: Flower colour variation is one of the most crucial selection criteria in the breeding of a flowering pot plant, as is also the case for azalea (Rhododendron simsii hybrids). Flavonoid biosynthesis was studied intensively in several species. In azalea, flower colour can be described by means of a 3-gene model. However, this model does not clarify pink-coloration. The last decade gene expression studies have been implemented widely for studying flower colour. However, the methods used were often only semi-quantitative or quantification was not done according to the MIQE-guidelines. We aimed to develop an accurate protocol for RT-qPCR and to validate the protocol to study flower colour in an azalea mapping population. Results: An accurate RT-qPCR protocol had to be established. RNA quality was evaluated in a combined approach by means of different techniques e.g. SPUD-assay and Experion-analysis. We demonstrated the importance of testing noRT-samples for all genes under study to detect contaminating DNA. In spite of the limited sequence information available, we prepared a set of 11 reference genes which was validated in flower petals; a combination of three reference genes was most optimal. Finally we also used plasmids for the construction of standard curves. This allowed us to calculate gene-specific PCR efficiencies for every gene to assure an accurate quantification. The validity of the protocol was demonstrated by means of the study of six genes of the flavonoid biosynthesis pathway. No correlations were found between flower colour and the individual expression profiles. However, the combination of early pathway genes (CHS, F3H, F3'H and FLS) is clearly related to co-pigmentation with flavonols. The late pathway genes DFR and ANS are to a minor extent involved in differentiating between coloured and white flowers. Concerning pink coloration, we could demonstrate that the lower intensity in this type of flowers is correlated to the expression of F3'H. Conclusions: Currently in plant research, validated and qualitative RT-qPCR protocols are still rare. The protocol in this study can be implemented on all plant species to assure accurate quantification of gene expression. We have been able to correlate flower colour to the combined regulation of structural genes, both in the early and late branch of the pathway. This allowed us to differentiate between flower colours in a broader genetic background as was done so far in flower colour studies. These data will now be used for eQTL mapping to comprehend even more the regulation of this pathway

    Passive immunization against Histomonas meleagridis does not protect turkeys from an experimental infection

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    Histomonosis or blackhead is a disease of gallinaceous birds, caused by the protozoan Histomonas meleagridis. As recent regulatory action has removed almost all drugs against this disease from the European market, the development of new prophylactics has become crucial. Identification of the protective immune mechanism would facilitate the choice and development of a vaccination strategy to prevent histomonosis. In this study, turkeys were either actively or passively immunized and were then challenged to assess the role of antibody-mediated immunity in the protection form this disease. Active immunization was performed either by experimental infection and treatment or by intramuscular injection with lysed H. meleagridis. Passive immunization was attempted by intraperitoneal administration of pooled, concentrated, neutralizing antisera from immunized donor animals to naive turkeys. A significantly higher IgG response was observed after infection and treatment than after intramuscular injection, which in turn was higher than the responses of placebo and control birds. While active immunization of turkeys by intramuscular injection of dead H. meleagridis antigens appeared not to be protective against histomonosis, immunization by infection and treatment did induce protection. However, no significant level of protection could be observed in the passively immunized birds. These results suggest that serum antibodies to H. meleagridis may not be a key component in the protection against this parasite. It is, however, possible that the concentration of antibodies at the mucosal site is insufficient. Therefore, further investigation on mucosal immune responses is necessary

    Rescaling the state in Flanders: new problem or old solution?

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    The rescaling of state emphasizes the rise of the regional and the city-regional scale in particular, as a new unit for policy making. The new governing strategy is referred to as regional governance, were both governmental and / or nongovernmental entities work together for the purpose of joint policy making or service delivery. This paper focuses on the operationalization of regional governance and links those findings to the actual debates surrounding the institutional organization of Flanders. A quantitative analysis of regional arrangements in Flanders and in the area of Mid-West Flanders, helps to clarify the nature of the rescaling of the state: the rescaling is the result of bottom – up and top – down initiatives and covers as well joined government arrangements as collaborative governance arrangements integrating public and private organizations. Further, we notice different roles of the Flemish government, as she is present at the regional level both as a meta-governor, actor and financier. By showing the nature and the content of regional governance, this paper helps to clarify the political debate that is going on now in Flanders. A debate dominated by classical institutional discussions and related to the issue of institutional fuzziness, efficiency and accountability. It is argued however that the political discussion and the organization of the public sector in Flanders should be renewed and should be inspired by this relatively new phenomenon. The rescaling of the regional state should be understood by using concepts, theories and instruments inspired by the literature on networks and collaborative governance

    Workflows, processes and technical solutions for seeding the research data commons

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    Queensland University of Technology (QUT) completed an Australian National Data Service (ANDS) funded “Seeding the Commons Project” to contribute metadata to Research Data Australia. The project employed two Research Data Librarians from October 2009 through to July 2010. Technical support for the project was provided by QUT’s High Performance Computing and Research Support Specialists. ---------- The project identified and described QUT’s category 1 (ARC / NHMRC) research datasets. Metadata for the research datasets was stored in QUT’s Research Data Repository (Architecta Mediaflux). Metadata which was suitable for inclusion in Research Data Australia was made available to the Australian Research Data Commons (ARDC) in RIF-CS format. ---------- Several workflows and processes were developed during the project. 195 data interviews took place in connection with 424 separate research activities which resulted in the identification of 492 datasets. ---------- The project had a high level of technical support from QUT High Performance Computing and Research Support Specialists who developed the Research Data Librarian interface to the data repository that enabled manual entry of interview data and dataset metadata, creation of relationships between repository objects. The Research Data Librarians mapped the QUT metadata repository fields to RIF-CS and an application was created by the HPC and Research Support Specialists to generate RIF-CS files for harvest by the Australian Research Data Commons (ARDC). ---------- This poster will focus on the workflows and processes established for the project including: ---------- • Interview processes and instruments • Data Ingest from existing systems (including mapping to RIF-CS) • Data entry and the Data Librarian interface to Mediaflux • Verification processes • Mapping and creation of RIF-CS for the ARD
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