Impact of bias correction on climate change signals over central Europe and the Iberian Peninsula

peer reviewedVegetation models for climate adaptation and mitigation strategies require spatially high-resolution climate input data in which the error with respect to observations has been previously corrected. To quantify the impact of bias correction, we examine the effects of quantile-mapping bias correction on the climate change signal (CCS) of climate, extremes, and biological variables from the convective regional climate model COSMO-CLM and two dynamic vegetation models (LPJ-GUESS and CARAIB). COSMO-CLM was driven and analyzed at 3 km horizontal resolution over Central Europe (CE) and the Iberian Peninsula (IP) for the transient period 1980–2070 under the RCP8.5 scenario. Bias-corrected and uncorrected climate simulations served as input to run the dynamic vegetation models over Wallonia. Main result of the impact of bias correction on the climate is a reduction of seasonal absolute precipitation by up to −55% with respect to uncorrected simulations. Yet, seasonal climate changes of precipitation and also temperature are marginally affected by bias correction. Main result of the impact of bias correction on changes in extremes is a robust spatial mean CCS of climate extreme indices over both domains. Yet, local biases can both over- and underestimate changes in these indices and be as large as the raw CCS. Changes in extremely wet days are locally enhanced by bias correction by more than 100%. Droughts in southern IP are exacerbated by bias correction, which increases changes in consecutive dry days by up to 14 days/year. Changes in growing season length in CE are affected by quantile mapping due to local biases ranging from 24 days/year in western CE to −24 days/year in eastern CE. The increase of tropical nights and summer days in both domains is largely affected by bias correction at the grid scale because of local biases ranging within ±14 days/year. Bias correction of this study strongly reduces the precipitation amount which has a strong impact on the results of the vegetation models with a reduced vegetation biomass and increases in net primary productivity. Nevertheless, there are large differences in the results of the two applied vegetation models.Multisectoral analysis of climate and land use change impacts on pollinators, plant diversity and crops yields (MAPPY)Projets multilatéraux de recherche (PINT-MULTI

Ergodicity and local limits for stochastic local and nonlocal p-Laplace equations

Ergodicity for local and nonlocal stochastic singular $p$-Laplace equations is proven, without restriction on the spatial dimension and for all $p\in[1,2)$. This generalizes previous results from [B. Gess and J. M. Tölle, J. Math. Pures Appl., 101 (2014), pp. 789--827], [W. Liu and J. M. Tölle, Electron. Commun. Probab., 16 (2011), pp. 447--457], [W. Liu, J. Evol. Equations, 9 (2009), pp. 747--770]. In particular, the results include the multivalued case of the stochastic (nonlocal) total variation flow, which solves an open problem raised in [V. Barbu, G. Da Prato, and M. Röckner, SIAM J. Math. Anal., 41 (2009), pp. 1106--1120]. Moreover, under appropriate rescaling, the convergence of the unique invariant measure for the nonlocal stochastic $p$-Laplace equation to the unique invariant measure of the local stochastic $p$-Laplace equation is proven.Peer reviewe

Impact of bias correction on climate change signals over central Europe and the Iberian Peninsula

Gefördert durch den Publikationsfonds der Universität Kasse

Assessing the effects of climate and land use changes on the distribution and growth of important plants species for pollinators

Pollination is a key ecosystem service vital to the preservation of wild plant communities and good agricultural behaviour. However, pollinators are rapidly declining in Europe, primarily as a result of human activity and climate change. Therefore, there is growing concern that observed declines in insect pollinators may impact on production and revenues from pollinator-dependent crops. In the forest, the presence of pollinators depends strongly on the openness of the canopy and the presence of wild plants that attract pollinators. The distribution of such plants is, therefore, crucial for estimating the pollinators presence. In general, however, there is incomplete knowledge of where those wild plants occur and how well they grow. To overcome this issue, we developed a species distribution model to predict the potential presence of important plant species for pollinators under present and future climatic conditions. The result of the distribution model is then refined using the dynamic vegetation model CARAIB. By combining the results of the distribution model and CARAIB, we can determine where the plants are located and calculate their net primary productivities.Multisectoral analysis of climate and land use change impacts on pollinators, plant diversity and crops yield

What future for pollinators in the understorey vegetation under the impact of climate change ?

editorial reviewed<p>Although understorey biomass is negligible in comparison to overstorey biomass, understorey vegetation supports the majority of biodiversity within forests. The diversity of  plant species in the understorey is important for pollinators, such as bees and butterflies, which use the available resources for food and shelter. However, the future of understorey vegetation is uncertain due to the impact of climate change and human activities.  Climate change and forest management are known to be among the most important factors affecting the diversity and abundance of understorey plant species. Most studies on understorey vegetation has often been limited in scope, either focusing on a small number of specific plant species or large-scale studies of plant functional types. In this study, we take a more comprehensive approach by combining the results of a species distribution model with a dynamic vegetation model to simulate the evolution of understorey vegetation at the species level. We select a set of 30 species important for pollinators. In order to cover a large climatic gradient, simulations are performed over the Walloon region in Belgium and the Eisenwurzen region in Austria. The climate dataset is provided by the regional climate model COSMO-CLM, which has a 3 km spatial resolution and covers the period from 1980 to 2070 under different greenhouse gas concentration scenarios (RCP 2.6 and RCP 8.5). Additionally, we investigate the effect of different forest management practices (thinning and clear-cutting) on overstorey and how they impact understorey vegetation. Overall, the study aims to provide new insights into the current and future state of understorey vegetation with a focus on the impact of climate change and forest management on key pollinator resources.</p&gt

Expression of protein-tyrosine phosphatases in Acute Myeloid Leukemia cells: <it>FLT3 ITD sustains high levels of DUSP6 expression</it>

Abstract Protein-tyrosine phosphatases (PTPs) are important regulators of cellular signaling and changes in PTP activity can contribute to cell transformation. Little is known about the role of PTPs in Acute Myeloid Leukemia (AML). The aim of this study was therefore to establish a PTP expression profile in AML cells and to explore the possible role of FLT3 ITD (Fms-like tyrosine kinase 3 with internal tandem duplication), an important oncoprotein in AML for PTP gene expression. PTP mRNA expression was analyzed in AML cells from patients and in cell lines using a RT-qPCR platform for detection of transcripts of 92 PTP genes. PTP mRNA expression was also analyzed based on a public microarray data set for AML patients. Highly expressed PTPs in AML belong to all PTP subfamilies. Very abundantly expressed PTP genes include PTPRC, PTPN2, PTPN6, PTPN22, DUSP1, DUSP6, DUSP10, PTP4A1, PTP4A2, PTEN, and ACP1. PTP expression was further correlated with the presence of FLT3 ITD, focusing on a set of highly expressed dual-specificity phosphatases (DUSPs). Elevated expression of DUSP6 in patients harboring FLT3 ITD was detected in this analysis. The mechanism and functional role of FLT3 ITD-mediated upregulation of DUSP6 was then explored using pharmacological inhibitors of FLT3 ITD signal transduction and si/shRNA technology in human and murine cell lines. High DUSP6 expression was causally associated with the presence of FLT3 ITD and dependent on FLT3 ITD kinase activity and ERK signaling. DUSP6 depletion moderately increased ERK1/2 activity but attenuated FLT3 ITD-dependent cell proliferation of 32D cells. In conclusion, DUSP6 may play a contributing role to FLT3 ITD-mediated cell transformation.</p

Expression of protein-tyrosine phosphatases in Acute Myeloid Leukemia cells : FLT3 ITD sustains high levels of DUSP6 expression

Protein-tyrosine phosphatases (PTPs) are important regulators of cellular signaling and changes in PTP activity can contribute to cell transformation. Little is known about the role of PTPs in Acute Myeloid Leukemia (AML). The aim of this study was therefore to establish a PTP expression profile in AML cells and to explore the possible role of FLT3 ITD (Fms-like tyrosine kinase 3 with internal tandem duplication), an important oncoprotein in AML for PTP gene expression. PTP mRNA expression was analyzed in AML cells from patients and in cell lines using a RT-qPCR platform for detection of transcripts of 92 PTP genes. PTP mRNA expression was also analyzed based on a public microarray data set for AML patients. Highly expressed PTPs in AML belong to all PTP subfamilies. Very abundantly expressed PTP genes include PTPRC, PTPN2, PTPN6, PTPN22, DUSP1, DUSP6, DUSP10, PTP4A1, PTP4A2, PTEN, and ACP1. PTP expression was further correlated with the presence of FLT3 ITD, focusing on a set of highly expressed dual-specificity phosphatases (DUSPs). Elevated expression of DUSP6 in patients harboring FLT3 ITD was detected in this analysis. The mechanism and functional role of FLT3 ITD-mediated upregulation of DUSP6 was then explored using pharmacological inhibitors of FLT3 ITD signal transduction and si/shRNA technology in human and murine cell lines. High DUSP6 expression was causally associated with the presence of FLT3 ITD and dependent on FLT3 ITD kinase activity and ERK signaling. DUSP6 depletion moderately increased ERK1/2 activity but attenuated FLT3 ITD-dependent cell proliferation of 32D cells. In conclusion, DUSP6 may play a contributing role to FLT3 ITD-mediated cell transformation