From Creativity to Responsible Createlligence® as Future Competence

Distinguished colleagues, ladies and gentlemen, it is a great honour and pleasure for me to talk to you today, a special day since it is my birthday, a special day since you have invited me to share my ideas and visions with you, all educational experts from quite a different region of the world, compared to that where I come from. But it is mostly relevant and necessary to exchange ideas and expertise, since what we are learning more and more today is that the world is a global village, that we all are connected into global systems, that we all together are children of that one and only mother earth, and only together can survive and develop

Upscaling fluxes from towers to regions, continents and global scales using datadriven approaches

Quantifying the current carbon cycle of terrestrial ecosystems requires that we translate spatially sparse measurements into consistent, gridded flux estimates at the regional scale. This is particularly challenging in heterogeneous regions such as the northern forests of the United States. We use a network of 17 eddy covariance flux towers deployed across the Upper Midwest region of northern Wisconsin and Michigan and upscale flux observations from towers to the regional scale. This region is densely instrumented and provides a unique test bed for regional upscaling. We develop a simple Diagnostic Carbon Flux Model (DCFM) and use flux observations and a data assimilation approach to estimate the model parameters. We then use the optimized model to produce gridded flux estimates across the region. We find that model parameters vary not only across plant functional types (PFT) but also within a given PFT. Our results show that the parameter estimates from a single site are not representative of the parameter values of a given PFT; cross-site (or joint) optimization using observations from multiple sites encompassing a range of site and climate conditions considerably improves the representativeness and robustness of parameter estimates. Parameter variability within a PFT can result in substantial variability in regional flux estimates. We also find that land cover representation including land cover heterogeneity and the spatial resolution and accuracy of land cover maps can lead to considerable uncertainty in regional flux estimates. In heterogeneous, complex regions, detailed and accurate land cover maps are essential for accurate estimation of regional fluxes

Upscaling carbon fluxes from towers to the regional scale: Influence of parameter variability and land cover representation on regional flux estimates

Quantifying the current carbon cycle of terrestrial ecosystems requires that we translate spatially sparse measurements into consistent, gridded flux estimates at the regional scale. This is particularly challenging in heterogeneous regions such as the northern forests of the United States. We use a network of 17 eddy covariance flux towers deployed across the Upper Midwest region of northern Wisconsin and Michigan and upscale flux observations from towers to the regional scale. This region is densely instrumented and provides a unique test bed for regional upscaling. We develop a simple Diagnostic Carbon Flux Model (DCFM) and use flux observations and a data assimilation approach to estimate the model parameters. We then use the optimized model to produce gridded flux estimates across the region. We find that model parameters vary not only across plant functional types (PFT) but also within a given PFT. Our results show that the parameter estimates from a single site are not representative of the parameter values of a given PFT; cross-site (or joint) optimization using observations from multiple sites encompassing a range of site and climate conditions considerably improves the representativeness and robustness of parameter estimates. Parameter variability within a PFT can result in substantial variability in regional flux estimates. We also find that land cover representation including land cover heterogeneity and the spatial resolution and accuracy of land cover maps can lead to considerable uncertainty in regional flux estimates. In heterogeneous, complex regions, detailed and accurate land cover maps are essential for accurate estimation of regional fluxes

Measurement of Inclusive and DiJet D*-Meson Photoproduction at the H1 Experiment at HERA

In der vorliegenden Arbeit wird der Produktionsmechanismus von Charm-Quarks in Elektron-Proton-Streuungen am Speicherring HERA untersucht. Der analysierte Datansatz entspricht Luminositaeten von 30.68 pb^-1, 68.23 pb^-1 und 93.39 pb^-1. Der Nachweis von Ereignissen mit Charm-Quarks erfolgt durch die Rekonstruktion von D*-Mesonen im kinematischen Bereich der Photoproduktion. D*-Mesonen werden erstmals mit Hilfe der dritten Stufe des Fast-Track-Triggers des H1-Experiments selektiert. Hierdurch konnte der Phasenraum im Vergleich zur vorangegangenen Messung entscheidend erweitert und die Statistik um einen Faktor acht erhoeht werden. Der untersuchte kinematische Bereich erstreckt sich ueber eine Photonvirtualitaet von Q^2 4 GeV bzw. p_t > 3 GeV im Bereich der Pseudorapiditaet |eta| < 1.5 untersucht. Hierbei wird verlangt, dass einer der selektierten Jets mit dem D*-Meson assoziiert ist. Die Rekonstruktion von zwei harten Partonen ermoeglicht einen tieferen Einblick in den Produktionsmechanismus der Charm-Quarks. Diese Messung zeigt, dass Prozesse mit aufgeloesten Photonen im untersuchten Phasenraum eine entscheidene Rolle bei der Photoproduktion von Charm-Quarks spielen. Einfach- und doppeltdifferentielle Wirkungsquerschnitte beider Ereignismengen werden mit Vorhersagen der pertubativer QCD in fuehrender und naechsthoeherer Ordnung verglichen

Selection of functional human antibodies from retroviral display libraries

Antibody library technology represents a powerful tool for the discovery and design of antibodies with high affinity and specificity for their targets. To extend the technique to the expression and selection of antibody libraries in an eukaryotic environment, we provide here a proof of concept that retroviruses can be engineered for the display and selection of variable single-chain fragment (scFv) libraries. A retroviral library displaying the repertoire obtained after a single round of selection of a human synthetic scFv phage display library on laminin was generated. For selection, antigen-bound virus was efficiently recovered by an overlay with cells permissive for infection. This approach allowed more than 10(3)-fold enrichment of antigen binders in a single selection cycle. After three selection cycles, several scFvs were recovered showing similar laminin-binding activities but improved expression levels in mammalian cells as compared with a laminin-specific scFv selected by the conventional phage display approach. Thus, translational problems that occur when phage-selected antibodies have to be transferred onto mammalian expression systems to exert their therapeutic potential can be avoided by the use of retroviral display libraries

Hydrogen bonding of nitroxide spin labels in membrane proteins

On the basis of experiments at 275 GHz, we reconsider the dependence of the continuous-wave EPR spectra of nitroxide spin-labeled protein sites in sensory- and bacteriorhodopsin on the micro-environment. The high magnetic field provides the resolution necessary to disentangle the effects of hydrogen bonding and polarity. In the gxx region of the 275 GHz EPR spectrum, bands are resolved that derive from spin-label populations carrying no, one or two hydrogen bonds. The gxx value of each population varies hardly from site to site, significantly less than deduced previously from studies at lower microwave frequencies. The fractions of the populations vary strongly, which provides a consistent description of the variation of the average gxx and the average nitrogen-hyperfine interaction Azz from site to site. These variations reflect the difference in the proticity of the micro-environment, and differences in polarity contribute marginally. Concomitant W-band ELDOR- detected NMR experiments on the corresponding nitroxide in perdeuterated water resolve population-specific nitrogen-hyperfine bands, which underlies the interpretation for the proteins

A field study of data analysis exercises in a bachelor physics course using the internet platform VISPA

Bachelor physics lectures on particle physics and astrophysics were complemented by exercises related to data analysis and data interpretation at the RWTH Aachen University recently. The students performed these exercises using the internet platform VISPA, which provides a development environment for physics data analyses. We describe the platform and its application within the physics course, and present the results of a student survey. The students acceptance of the learning project was positive. The level of acceptance was related to their individual preference for learning with a computer. Furthermore, students with good programming skills favor working individually, while students who attribute themselves having low programming abilities favor working in teams. The students appreciated approaching actual research through the data analysis tasks.Comment: 21 pages, 8 figures, 1 table, for the internet platform VISPA see http://vispa.physik.rwth-aachen.d