160 research outputs found

    30 Jahre Heimatforscherfortbildung in Niedersachsen. Bilanz und Ausblick

    Get PDF
    Regionale Forschung, besonders historische oder kulturhistorische Regionalforschung, wird häufig von sogenannten „Heimatforschern“ betrieben. In Niedersachsen geschieht dies in einer Vielzahl von unterschiedlichen Vereinen. Oftmals kennen die „Heimatforscher“ die Bestände von Archiven, haben Einblick in die private Überlieferung vor Ort und ein großes thematisches Fachwissen. Trotzdem gestaltet sich der Austausch sowohl von Seiten dieser versierten Laien als auch der universitären Regionalhistoriker oft als schwierig. Regional- und Lokalhistorisches Wissen geht dadurch zwangsläufig verloren. In Niedersachsen gibt es aber auch Erfahrungen anderer Art. Dort führte der Niedersächsische Heimatbund ab 1983 systematisch Fortbildungen für Heimatforscher durch. Sie führten von 1984–1995 zu einer Qualifizierung der Ehrenamtlichen und zu einem Austausch mit der universitären Wissenschaft. Neue Formate versuchen, an diese Arbeit anzuknüpfen, Wissenschaftler für die Bedeutung dieser Aufgabe zu sensibilisieren und neue, auch jüngere Zielgruppen für die Heimatforschung zu erschließen, die heute in Anbetracht sinkender Fördermittel wichtiger erscheinen denn je.There is a multitude of different non-profit associations in Lower Saxony that engage in researching local history. This large number of associations and the differences in their approaches towards local history renders collaboration of associations, individual private researchers and professional historians difficult. Without a systematic exchange of professional and non-professional research, local knowledge is eventually lost. Workshops and seminars for non-professional researchers addressed this issue between 1984 and 1995 in order to establish closer collaboration of Universities and private researchers and a more fruitful exchange of knowledge between the two. New formats of collaboration are now reviving this endeavour to sensitize scientists of the importance of this task and to develop new and younger audiences for local history since in the light of declining funding opportunities for this research field new citizen scientists seem to be more important than ever

    Solving the Klein-Gordon equation using Fourier spectral methods: A benchmark test for computer performance

    Get PDF
    The cubic Klein-Gordon equation is a simple but non-trivial partial differential equation whose numerical solution has the main building blocks required for the solution of many other partial differential equations. In this study, the library 2DECOMP&FFT is used in a Fourier spectral scheme to solve the Klein-Gordon equation and strong scaling of the code is examined on thirteen different machines for a problem size of 512^3. The results are useful in assessing likely performance of other parallel fast Fourier transform based programs for solving partial differential equations. The problem is chosen to be large enough to solve on a workstation, yet also of interest to solve quickly on a supercomputer, in particular for parametric studies. Unlike other high performance computing benchmarks, for this problem size, the time to solution will not be improved by simply building a bigger supercomputer.Comment: 10 page

    Biological trait profiles discriminate between native and non-indigenous marine invertebrates

    Get PDF
    The increasing rate of marine invasions to Western Europe in recent decades highlights the importance of addressing the central questions of invasion biology: what allows an invader to be successful, and which species are likely to become invasive? Consensus is currently lacking regarding the key traits that determine invasiveness in marine species and the extent to which invasive and indigenous species differ in their trait compositions. This limits the ability to predict invasive potential. Here we propose a method based on trait profiles which can be used to predict non-indigenous species likely to cause the greatest impact and native species with a tendency for invasion. We compiled a database of 12 key biological and life history traits of 85 non-indigenous and 302 native marine invertebrate species from Western Europe. Using multivariate methods, we demonstrate that biological traits were able to discriminate between native and non-indigenous species with an accuracy of 78%. The main discriminant traits included body size, lifespan, fecundity, offspring protection, burrowing depth and, to a lesser extent, pelagic stage duration. Analysis revealed that the typical non-indigenous marine invertebrate is a mid-sized, long-lived, highly fecund suspension feeder which either broods its offspring or has a pelagic stage duration of 1–30 days, and is either attached-sessile or burrows to a depth of 5 cm. Biological traits were also able to predict native species classed as “potentially invasive” with an accuracy of 78%. Targeted surveillance and proactive management of invasive species requires accurate predictions of which species are likely to become invasive in the future. Our findings add to the growing evidence that non-indigenous species possess a greater affinity for certain traits. These traits are typically present in the profile of “potentially invasive” native species

    Health-Related Physical Fitness and Arterial Stiffness in Childhood Cancer Survivors

    Get PDF
    Introduction: Despite decreasing mortality in pediatric oncology as a result of standardized treatment protocols, the high number of functional and cardiovascular late sequelae due to anticarcinogenic therapy remains unchanged. The aim of this study was to further assess functional limitations in Health-related Physical Fitness (HRPF) and cardiovascular risk by means of markers of arterial stiffness in Childhood Cancer Survivors (CCS).Materials and Methods: Between March 2016 and August 2017 a total of 92 CCS (Age 12.5 ± 4.2 years, 43 girls) were recruited from their routine follow-up outpatient visit. HRPF was assessed using five Fitnessgram® tasks. Pulse Wave Velocity (PWV) along with peripheral and central blood pressure were assessed using oscillometric measurements performed by Mobil-O-Graph. Z-scores were used to compare the test results either to German reference values or to a recent healthy reference cohort.Results: In CCS, the HRPF was significantly reduced (z-score: −0.28 ± 1.01, p = 0.011) as compared to healthy peers. The peripheral Systolic Blood Pressure (pSBP) was significantly increased (z-score: 0.31 ± 1.11, p = 0.017) and the peripheral Diastolic Blood Pressure (pDBP) was decreased (z-score: −0.30 ± 1.25, p = 0.040), resulting in an increased pulse pressure. The PWV (p = 0.649) and cSBP (p = 0.408), were neither increased nor showed any association to HRPF.Discussion: CCS showed functional limitations in HRPF and an increased pulse pressure, which acts as an early onset parameter of arterial stiffness. Both a low HRPF and impaired hemodynamics are independent cardiovascular risk factors and needs to be taken into consideration in tertiary prevention of CCS

    Automated pathway and reaction prediction facilitates in silico identification of unknown metabolites in human cohort studies

    Get PDF
    Identification of metabolites in non-targeted metabolomics continues to be a bottleneck in metabolomics studies in large human cohorts. Unidentified metabolites frequently emerge in the results of association studies linking metabolite levels to, for example, clinical phenotypes. For further analyses these unknown metabolites must be identified. Current approaches utilize chemical information, such as spectral details and fragmentation characteristics to determine components of unknown metabolites. Here, we propose a systems biology model exploiting the internal correlation structure of metabolite levels in combination with existing biochemical and genetic information to characterize properties of unknown molecules. Levels of 758 metabolites (439 known, 319 unknown) in human blood samples of 2279 subjects were measured using a non-targeted metabolomics platform (LC-MS and GC-MS). We reconstructed the structure of biochemical pathways that are imprinted in these metabolomics data by building an empirical network model based on 1040 significant partial correlations between metabolites. We further added associations of these metabolites to 134 genes from genome-wide association studies as well as reactions and functional relations to genes from the public database Recon 2 to the network model. From the local neighborhood in the network, we were able to predict the pathway annotation of 180 unknown metabolites. Furthermore, we classified 100 pairs of known and unknown and 45 pairs of unknown metabolites to 21 types of reactions based on their mass differences. As a proof of concept, we then looked further into the special case of predicted dehydrogenation reactions leading us to the selection of 39 candidate molecules for 5 unknown metabolites. Finally, we could verify 2 of those candidates by applying LC-MS analyses of commercially available candidate substances. The formerly unknown metabolites X-13891 and X-13069 were shown to be 2-dodecendioic acid and 9-tetradecenoic acid, respectively. Our data-driven approach based on measured metabolite levels and genetic associations as well as information from public resources can be used alone or together with methods utilizing spectral patterns as a complementary, automated and powerful method to characterize unknown metabolites

    On the Vanishing Displacement Current Limit for Time-Harmonic Maxwell Equations

    Get PDF
    This paper considers a transmission boundary-value problem for the time-harmonic Maxwell equations neglecting displacement currents which is frequently used for the numerical computation of eddy-currents. Across material boundaries the tangential components of the magnetic field H and the normal component of the magnetization müH are assumed to be continuous. this problem admits a hyperplane of solutions if the domains under consideration are multiply connected. Using integral equation methods and singular perturbation theory it is shown that this hyperplane contains a unique point which is the limit of the classical electromagnetic transmission boundary-value problem for vanishing displacement currents. Considering the convergence proof, a simple contructive criterion how to select this solution is immediately derived

    Die Bedeutung von Bruchstörfällen bei Kernkraftwerken mit Hochtemperaturreaktor und Heliumturbinenkreislauf in nichtintegrierter Bauweise

    No full text
    In the presented report the dynarnic behaviour to be expected by circuit fracture accidents and therefore the resulting effects on the cycle components as well as the required safety devices are investigated. The subject of investigation is a conceptual design of a power plant with a closed-cycle HTR-helium turbine plant in non-integrated type of arrangement (NINT). The accidental behaviour of this closed cycle HTR-NINT-helium turbine plant is investigated for the relevant circuit fracture. A representative description is given for the hot gas duct fracture. The requirements for the safety devices with regard to limitation of activity release and observation from other important criteria, e. g. integrity of the reactor are derived from most severe accident stresses The system-required safety devices are specified. The investigation of circuit ruptures show, that undue high stress arg environment and plant components can be avoided

    GM-CSF and IL-33 Orchestrate Polynucleation and Polyploidy of Resident Murine Alveolar Macrophages in a Murine Model of Allergic Asthma

    No full text
    Allergic asthma is a chronical pulmonary disease with high prevalence. It manifests as a maladaptive immune response to common airborne allergens and is characterized by airway hyperresponsiveness, eosinophilia, type 2 cytokine-associated inflammation, and mucus overproduction. Alveolar macrophages (AMs), although contributing to lung homeostasis and tolerance to allergens at steady state, have attracted less attention compared to professional antigen-presenting and adaptive immune cells in their contributions. Using an acute model of house dust mite-driven allergic asthma in mice, we showed that a fraction of resident tissue-associated AMs, while polarizing to the alternatively activated M2 phenotype, exhibited signs of polynucleation and polyploidy. Mechanistically, in vitro assays showed that only Granulocyte-Macrophage Colony Stimulating Factor and interleukins IL-13 and IL-33, but not IL-4 or IL-5, participate in the establishment of this phenotype, which resulted from division defects and not cell-cell fusion as shown by microscopy. Intriguingly, mRNA analysis of AMs isolated from allergic asthmatic lungs failed to show changes in the expression of genes involved in DNA damage control except for MafB. Altogether, our data support the idea that upon allergic inflammation, AMs undergo DNA damage-induced stresses, which may provide new unconventional therapeutical approaches to treat allergic asthma
    corecore