1,958 research outputs found

    AstroGrid-D: Enhancing Astronomic Science with Grid Technology

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    We present AstroGrid-D, a project bringing together astronomers and experts in Grid technology to enhance astronomic science in many aspects. First, by sharing currently dispersed resources, scientists can calculate their models in more detail. Second, by developing new mechanisms to efficiently access and process existing datasets, scientific problems can be investigated that were until now impossible to solve. Third, by adopting Grid technology large instruments such as robotic telescopes and complex scientific workflows from data aquisition to analysis can be managed in an integrated manner. In this paper, we present prominent astronomic use cases, discuss requirements on a Grid middleware and present our approach to extend/augment existing middleware to facilitate the improvements mentioned above

    Effects of Periodic Unsteady Wake Flow and Pressure Gradient on Boundary Layer Transition Along the Concave Surface of a Curved Plate

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    Boundary layer transition and development on a turbomachinery blade is subjected to highly periodic unsteady turbulent flow, pressure gradient in longitudinal as well as lateral direction, and surface curvature. To study the effects of periodic unsteady wakes on the concave surface of a turbine blade, a curved plate was utilized. On the concave surface of this plate, detailed experimental investigations were carried out under zero and negative pressure gradient. The measurements were performed in an unsteady flow research facility using a rotating cascade of rods positioned upstream of the curved plate. Boundary layer measurements using a hot-wire probe were analyzed by the ensemble-averaging technique. The results presented in the temporal-spatial domain display the transition and further development of the boundary layer, specifically the ensemble-averaged velocity and turbulence intensity. As the results show, the turbulent patches generated by the wakes have different leading and trailing edge velocities and merge with the boundary layer resulting in a strong deformation and generation of a high turbulence intensity core. After the turbulent patch has totally penetrated into the boundary layer, pronounced becalmed regions were formed behind the turbulent patch and were extended far beyond the point they would occur in the corresponding undisturbed steady boundary layer

    Calcium sensitivity and the Frank-Starling mechanism of the heart are increased in titin N2B region deficient mice

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    Previous work suggests that titin-based passive tension is a factor in the Frank-Starling mechanism of the heart, by increasing length-dependent activation (LDA) through an increase in calcium sensitivity at long sarcomere length. We tested this hypothesis in a mouse model (N2B KO model) in which titin-based passive tension is elevated as a result of the excision of the N2B element, one of cardiac titin's spring elements. LDA was assessed by measuring the active tension-pCa (-log[Ca2+]) relationship at sarcomere length (SLs) of 1.95, 2.10 and 2.30mum in WT and N2B KO skinned myocardium. LDA was positively correlated with titin-based passive tension, due to an increase in calcium sensitivity at the longer SLs in the KO. For example, at pCa 6.0 the KO:WT tension ratio was 1.28+/-0.07 and 1.42+/-0.04 at SLs of 2.1 and 2.3mum, respectively. There was no difference in protein expression or phosphorylation of sarcomeric proteins. We also measured the calcium sensitivity after PKA treating the skinned muscle and found that titin-based passive tension was also now correlated with LDA, with a slope that was significantly increased compared to no PKA treatment. Finally, we performed isolated heart experiments and measured the Frank-Starling relation (slope of developed wall stress-LV volume relation) as well as diastolic stiffness (slope of diastolic wall stress - volume relation). The FSM was more pronounced in the N2B KO hearts and the slope of the FSM correlated with diastolic stiffness. These findings support that titin-based passive tension triggers an increase in calcium sensitivity at long sarcomere length, thereby playing an important role in the Frank-Starling mechanism of the heart

    Automatisierung des Bio-Plex Pro Analyseverfahrens

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    FĂŒr den simultanen Nachweis mehrerer Analyten innerhalb einer Probe ist die Bead-basierte Multiplexanalytik ein hĂ€ufig verwendetes Verfahren und wird beispielsweise zur Quantifizierung von Proteinen genutzt. Die aufwendige DurchfĂŒhrung der Assays soll durch Automatisierung einerseits dem Anwender abgenommen werden, wĂ€hrend andererseits die Genauigkeit und Reproduzierbarkeit der Analyse gesteigert wird. Die Automatisierung des Bio-Plex Proℱ Assays ist mit dem Pipettierroboter Tecan Freedom EVO 200 umgesetzt worden. Es ist ein Skript mit der Software Freedom EVOwareÂź entwickelt worden, welches die Probenvorbereitung des Assays vollstĂ€ndig ĂŒbernimmt. FĂŒr einen Vergleich der manuellen und automatisierten Methode sind die humanen Zytokine IL-2, IL-4, IL-10, GM-CSF, IFN-Îł und TNF-α in einer achtstufigen StandardverdĂŒnnungsreihe und in unterschiedlich konzentrierten Proben gemessen worden. Die Berechnung der Streuungen (Standardabweichung und Variationskoeffizient) der einzelnen StandardverdĂŒnnungsreihen sowie der Vergleich von gemessenen und erwarteten Konzentrationen der automatisierten und manuellen Methode zeigen, dass die Automatisierung neben der zeitlichen Optimierung auch die Genauigkeit und Reproduzierbarkeit der Analyse verbessert.Bead-based multpiplex analysis is frequently used for the simultaneous detection of multiple analytes within a sample. Such assays are commonly used to quantify proteins. The automation of the process relieves the user from the complex assay conductance and on the other hand increases the accuracy and reproducibility of the analysis. The automation of the Bio-Plex Proℱ assay has been successfully implemented with the pipetting-robot Tecan Freedom EVO 200. A script has been developed, using the Freedom EVOwareÂź which has the ability to perform the complete assay procedure. For a comparison between manual and automated methods, the human cytokines IL-2, IL-4, IL-10, GM-CSF, IFN-Îł and TNF-α were analysed by an eight-point standard dilution series and with samples of different concentrations. The calculation of the variances (standard deviation and coefficient of variation) of the single standard dilution series as well as the comparison of the observed and expected concentrations of the manual or automated method show the higher precision and reproducibility of the automated process in addition to its time-saving nature

    Spatial accessibility and social inclusion: The impact of Portugal's last health reform

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    Health policies seek to promote access to health care and should provide appropriate geographical accessibility to each demographical functional group. The dispersal demand of health‐careservices and the provision for such services atfixed locations contribute to the growth of inequality intheir access. Therefore, the optimal distribution of health facilities over the space/area can lead toaccessibility improvements and to the mitigation of the social exclusion of the groups considered mostvulnerable. Requiring for such, the use of planning practices joined with accessibility measures. However,the capacities of Geographic Information Systems in determining and evaluating spatial accessibility inhealth system planning have not yet been fully exploited. This paper focuses on health‐care services planningbased on accessibility measures grounded on the network analysis. The case study hinges on mainlandPortugal. Different scenarios were developed to measure and compare impact on the population'saccessibility. It distinguishes itself from other studies of accessibility measures by integrating network data ina spatial accessibility measure: the enhanced two‐stepfloating catchment area. The convenient location forhealth‐care facilities can increase the accessibility standards of the population and consequently reducethe economic and social costs incurred. Recently, the Portuguese government implemented a reform thataimed to improve, namely, the access and equity in meeting with the most urgent patients. It envisaged,in terms of equity, the allocation of 89 emergency network points that ensured more than 90% of thepopulation be within 30 min from any one point in the network. Consequently, several emergency serviceswere closed, namely, in rural areas. This reform highlighted the need to improve the quality of the emergencycare, accessibility to each care facility, and equity in their access. Hence, accessibility measures becomean efficient decision‐making tool, despite its absence in effective practice planning. According to anapplication of this type of measure, it was possible to verify which levels of accessibility were decreased,including the most disadvantaged people, with a larger time of dislocation of 12 min between 2001 and 2011

    The Single Complete Denture – A Case Report.

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    The single complete denture is a complex prosthesis that requires a complete understanding of the basics of prosthetic rehabilitation of lost natural dentition. Several difficulties are encountered in providing a successful single complete denture treatment, the most common being repeated fracture of the prosthesis. An ideal solution to strengthen the single complete denture bases is to provide metal reinforcement by fabrication of metal based single complete denture. Another common problem in single complete denture is attrition of denture teeth while opposing natural dentition which can be taken care of by providing metal occlusals in single complete dentures. Metal occlusal surfaces preserve the established occlusion and prevent loss of vertical dimension. This case report describes the clinical management and step by step fabrication of single complete denture with metal denture base and metal occlusals in a patient with completely edentulous maxillary jaw and partially edentulous mandibular jaw.&nbsp

    Reducing RBM20 activity improves diastolic dysfunction and cardiac atrophy

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    Impaired diastolic filling is a main contributor to heart failure with preserved ejection fraction (HFpEF), a syndrome with increasing prevalence and no treatment. Both collagen and the giant sarcomeric protein titin determine diastolic function. Since titin's elastic properties can be adjusted physiologically, we evaluated titin-based stiffness as a therapeutic target. We adjusted RBM20-dependent cardiac isoform expression in the titin N2B knockout mouse with increased ventricular stiffness. A ~50 % reduction of RBM20 activity does not only maintain cardiac filling in diastole but also ameliorates cardiac atrophy and thus improves cardiac function in the N2B-deficient heart. Reduced RBM20 activity partially normalized gene expression related to muscle development and fatty acid metabolism. The adaptation of cardiac growth was related to hypertrophy signaling via four-and-a-half lim-domain proteins (FHLs) that translate mechanical input into hypertrophy signals. We provide a novel link between cardiac isoform expression and trophic signaling via FHLs and suggest cardiac splicing as a therapeutic target in diastolic dysfunction. KEY MESSAGE: Increasing the length of titin isoforms improves ventricular filling in heart disease. FHL proteins are regulated via RBM20 and adapt cardiac growth. RBM20 is a therapeutic target in diastolic dysfunction

    Supercomplex Organization of the Electron Transfer System in Marine Bivalves, a Model of Extreme Longevity

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    The mitochondrial oxidative stress theory of aging suggests that the organelle’s decay contributes to the aging phenotype via exacerbated oxidative stress, loss of organ coordination and energetics, cellular integrity, and activity of the mitochondrial electron transfer system (ETS). Recent advances in understanding the structure of the ETS show that the enzymatic complexes responsible for oxidative phosphorylation are arranged in supramolecular structures called supercomplexes that lose organization during aging. Their exact role and universality among organisms are still under debate. Here, we take advantage of marine bivalves as an aging model to compare the structure of the ETS among species ranging from 28 to 507 years in maximal life span. Our results show that regardless of life span, the bivalve ETS is arrayed as a set of supercomplexes. However, bivalve species display varying degrees of ETS supramolecular organization with the highest supercomplex structures found in Arctica islandica, the longest-lived of the bivalve species under study. We discuss this comparative model in light of differences in the nature and stoichiometry of these complexes and highlight the potential link between the complexity of these superstructures and longer life spans
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