221 research outputs found

    INTERACTION BETWEEN PLATE AND LATERAL-TORSIONAL BUCKLING WITH REGARD TO RESIDUAL STRESSES

    Get PDF
    The complex of strain hardening of steel, occurring residual stresses, interaction of plate and member buckling significantly affects the stability condition of beam-columns. Theoretical results obtained by the energy method relying on the theory of plastic deformation match test results

    LOAD TESTS ON THE FOUR-SPAN STRUCTURE OF THE RAILWAY BRIDGE OVER THE TISZA AT CSONGRÁD-SZENTES

    Get PDF
    New bridges can be opened to traffic only after a subsequent load test. The minimal aim of these checks is to show that the structure fulfils the design requirements given in the corresponding Code and its real behaviour approximates the expected one. However, these pieces of information do not provide an explanation for all the deviations. Therefore, if the objective and financial conditions are given, it is advisable to carry out additional measurements, which can be analyzed later to describe more accurately the behaviour of the structure, which, in turn, widens the possibilities of assuming a more realistic structural model and which provides aid and reference point for design practice in the future

    TESTS ON THE STEEL STRUCTURE OF A RAILWAY BRIDGE

    Get PDF

    GPU accelerated investigation of a dual-frequency driven nonlinear oscillator

    Get PDF
    The bifurcation structure of a dual-frequency driven, second order nonlinear oscillator (Keller–Miksis equation) is investigated by exploiting the high computational resources of professional GPUs. The numerical scheme of the applied initial value problem solver was the explicit, adaptive Runge–Kutta–Cash–Karp method with embedded error estimation using solutions of order 4 and 5. The four dimensional parameter space (amplitudes and frequencies of the driving) is explored by means of several high resolution bi-parametric plots with the amplitudes as control parameters at fixed frequencies. The resolution of the control parameter plane is 500 × 500 with 10 initial conditions at each parameter pair (altogether 2.5 million initial value problems in each bi-parametric plot). The program code for one fine parameter scan runs approximately 50 times faster on a Tesla K20 GPU (Kepler architecture) than on an Intel i7-4790 4 core CPU even applying double precision floating point operations

    Climate change impacts and product lines

    Get PDF
    This paper summarizes the main effects of extreme weather events on agricultural production and demonstrates their economic consequences. For cost-benefit analysis of economic impacts and for determination of risk levels simulation models are needed that contains the relationship between product line levels and elements. WIN-SIM model is developed for this goal, specialized for wine production. The model is suitable to analyze the market share, the cost and income relations as well as the relation structure of the product lines. The four levels of the model (site, vine growing, wine production and wine market levels) have individual values added from the aspect of end product, where the product line sets out from the site level and gets through the levels up to the consumer segments. Theoretically, all elements can be connected to any element of the next level and sublevel, but there are “prohibited contacts” because of professional, regulation or production practice reasons

    Climate change impacts and product lines

    Get PDF
    This paper summarizes the main effects of extreme weather events on agricultural production and demonstrates their economicconsequences. For cost-benefit analysis of economic impacts and for determination of risk levels simulation models are needed that containsthe relationship between product line levels and elements. WIN-SIM model is developed for this goal, specialized for wine production. Themodel is suitable to analyze the market share, the cost and income relations as well as the relation structure of the product lines. The four levelsof the model (site, vine growing, wine production and wine market levels) have individual values added from the aspect of end product, wherethe product line sets out from the site level and gets through the levels up to the consumer segments. Theoretically, all elements can beconnected to any element of the next level and sublevel, but there are “prohibited contacts” because of professional, regulation or productionpractice reasons

    Micro-scale Experimental System Coupled with Fluorescence-based Estimation of Fungal Biomass to Study Utilisation of Plant Substrates.

    Get PDF
    The degradation capacity and utilisation of complex plant substrates are crucial for the functioning of saprobic fungi and different plant symbionts with fundamental functions in ecosystems. Measuring the growth capacity and biomass of fungi on such systems is a challenging task. We established a new micro-scale experimental setup using substrates made of different plant species and organs as media for fungal growth. We adopted and tested a reliable and simple titration-based method for the estimation of total fungal biomass within the substrates using fluorescence-labelled lectin. We found that the relationship between fluorescence intensity and fungal dry weight was strong and linear but differed among fungi. The effect of the plant organ (i.e. root vs. shoot) used as substrate on fungal growth differed among plant species and between root endophytic fungal species. The novel microscale experimental system is useful for screening the utilisation of different substrates, which can provide insight into the ecological roles and functions of fungi. Furthermore, our fungal biomass estimation method has applications in various fields. As the estimation is based on the fungal cell wall, it measures the total cumulative biomass produced in a certain environment

    Aggressiveness of human melanoma xenograft models is promoted by aneuploidy-driven gene expression deregulation.

    Get PDF
    Melanoma is a devastating skin cancer characterized by distinct biological subtypes. Besides frequent mutations in growth- and survival-promoting genes like BRAF and NRAS, melanomas additionally harbor complex non-random genomic alterations. Using an integrative approach, we have analysed genomic and gene expression changes in human melanoma cell lines (N=32) derived from primary tumors and various metastatic sites and investigated the relation to local growth aggressiveness as xenografts in immuno-compromised mice (N=22). Although the vast majority >90% of melanoma models harbored mutations in either BRAF or NRAS, significant differences in subcutaneous growth aggressiveness became obvious. Unsupervised clustering revealed that genomic alterations rather than gene expression data reflected this aggressive phenotype, while no association with histology, stage or metastatic site of the original melanoma was found. Genomic clustering allowed separation of melanoma models into two subgroups with differing local growth aggressiveness in vivo. Regarding genes expressed at significantly altered levels between these subgroups, a surprising correlation with the respective gene doses (>85% accordance) was found. Genes deregulated at the DNA and mRNA level included well-known cancer genes partly already linked to melanoma (RAS genes, PTEN, AURKA, MAPK inhibitors Sprouty/Spred), but also novel candidates like SIPA1 (a Rap1GAP). Pathway mining further supported deregulation of Rap1 signaling in the aggressive subgroup e.g. by additional repression of two Rap1GEFs. Accordingly, siRNA-mediated down-regulation of SIPA1 exerted significant effects on clonogenicity, adherence and migration in aggressive melanoma models. Together our data suggest that an aneuploidy-driven gene expression deregulation drives local aggressiveness in human melanoma

    Mild Type 2 Diabetes Mellitus Reduces the Susceptibility of the Heart to Ischemia/Reperfusion Injury: Identification of Underlying Gene Expression Changes.

    Get PDF
    Despite clinical studies indicating that diabetic hearts are more sensitive to ischemia/reperfusion injury, experimental data is contradictory. Although mild diabetes prior to ischemia/reperfusion may induce a myocardial adaptation, further research is still needed. Nondiabetic Wistar (W) and type 2 diabetic Goto-Kakizaki (GK) rats (16-week-old) underwent 45 min occlusion of the left anterior descending coronary artery and 24 h reperfusion. The plasma glucose level was significantly higher in diabetic rats compared to the nondiabetics. Diabetes mellitus was associated with ventricular hypertrophy and increased interstitial fibrosis. Inducing myocardial infarction increased the glucose levels in diabetic compared to nondiabetic rats. Furthermore, the infarct size was smaller in GK rats than in the control group. Systolic and diastolic functions were impaired in W + MI and did not reach statistical significance in GK + MI animals compared to the corresponding controls. Among the 125 genes surveyed, 35 genes showed a significant change in expression in GK + MI compared to W + MI rats. Short-term diabetes promotes compensatory mechanisms that may provide cardioprotection against ischemia/reperfusion injury, at least in part, by increased antioxidants and the upregulation of the prosurvival PI3K/Akt pathway, by the downregulation of apoptotic genes, proinflammatory cytokine TNF-alpha, profibrogenic TGF-beta, and hypertrophic marker alpha-actin-1
    corecore