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This dataset contains all data on which the following publication below is based. Paper Citation: Risch Anita C., Zimmermann, Stefan, Schütz, Martin, Borer, Elizabeth T., Broadbent, Arthur A.D., Caldeira, Maria C., Davies, Kendi F., Eisenhauer, Nico, Eskelinen, Anu, Fay, Philip A., Hagedorn, Frank, Knops, Johannes M.H., Lembrechts, Jonas, J., MacDougall, Andrew S., McCulley, Rebecca L., Melbourne, Brett A., Moore, Joslin L., Power, Sally A., Seabloom, Eric W., Silveira, Maria L., Virtanen, Risto, Yahdjian, Laura, Ochoa-Hueso, Raul (accepted). Drivers of the microbial metabolic quotient across global grasslands. Global Ecology and Biogeography Please cite this paper together with the citation for the datafile. The microbial metabolic quotient (MMQ; mg CO2-C mg MBC-1 h-1), defined as the amount of microbial CO2 respired (MR; mg CO2-C kg soil-1 h-1) per unit of microbial biomass C (MBC; mg C kg soil-1), is a key parameter for understanding the microbial regulation of the carbon (C) cycle, including soil C sequestration. Here, we experimentally tested hypotheses about the individual and interactive effects of multiple nutrient addition (NPK+micronutrients) and herbivore exclusion on MR, MBC, and MMQ across 23 sites (5 continents). Our sites encompassed a wide range of edaphoclimatic conditions, thus we assessed which edaphoclimatic variables affected MMQ the most and how they interacted with our treatments. Soils were collected in plots with established experimental treatments. MR was assessed in a five-week laboratory incubation without glucose addition, MBC via substrate-induced respiration. MMQ was calculated as MR/MBC and corrected for soil temperatures (MMQsoil). Using LMMs and SEMs, we analysed how edaphoclimatic characteristics and treatments interactively affected MMQsoil. MMQsoil was higher in locations with higher mean annual temperature, lower water holding capacity, and soil organic C concentration, but did not respond to our treatments across sites as neither MR nor MBC changed. We attributed this relative homeostasis to our treatments to the modulating influence of edaphoclimatic variables. For example, herbivore exclusion, regardless of fertilization, led to greater MMQsoil only at sites with lower soil organic C (-1.7%). Our results pinpoint the main variables related to MMQsoil across grasslands and emphasize the importance of the local edaphoclimatic conditions in controlling the response of the C cycle to anthropogenic stressors. By testing hypotheses about MMQsoil across global edaphoclimatic gradients, this work also helps to align the conflicting results of prior studies.

Fehler sind in der Entwicklung von komplexen Software-Systemen unvermeidbar. Entwickler*innen sind daher unausweichlich mit Fehlern konfrontiert, deren Korrekturen zukünftige Ressourcen binden und daher in weiterer Folge notwendige Fehlerbehebungen mit Implementierungen neuer Funktionen konkurrieren. Zudem steigen die Korrekturkosten umso mehr, je später die Fehler im Projektfortschritt entdeckt werden. Um diesen Umstand entsprechend zu adressieren, wird die Software-Qualitätssicherung frühzeitig in den Software-Entwicklungsprozess eingebunden. Hierfür wird vor allem der Einsatz von statischer Analyse empfohlen, welche bereits in sehr frühen Konstruktionsphasen eingesetzt werden kann. Deren Ergebnisberichte sind jedoch typischerweise sehr umfangreich, zeigen viele Regelverletzungen auf und unterstützen durch mangelnde Priorisierung Entwicklungsteams nicht in geeignetem Ausmaß. Demzufolge wäre es von unmittelbarem Vorteil, wenn diejenigen Hinweise statischer Analyse frühzeitig identifiziert werden, welche in weiterer Folge zu Fehlerwirkungen bei der Anwendung der Software-Systeme führen, um resultierende Folgekosten für Korrekturen zu reduzieren. Gegenstand dieser Arbeit ist es daher, Fehlerberichte von Releases und Hinweise statischer Analyse gegenüberzustellen. Auf Basis dieser Korrelationen werden geeignete Methoden der künstlichen Intelligenz eingesetzt, um praxistaugliche Modelle für die Anwendung im produktiven Umfeld zu trainieren und die Vorhersage von zukünftigen Fehlerwirkungen effektiv zu ermöglichen. Making errors during software development is unavoidable. Developers inevitably make errors that take additional time to fix later on. As a consequence efforts for bugfixing compete with implementing new features. Typically the later bugs are found, the higher the cost for remediation. To address this concern, software testing should start as early as possible in software development lifecycle. For this purpose, static analysis is proposed, but typically shows too many findings and hence do not support development teams appropriately. So it would be a benefit to premature detect those findings in static analysis that will result in failures to reduce subsequent efforts notably. The purpose of the thesis is to analyse failure data from issue tracking systems that are correlated to findings from static analysis. Thereupon an artificial intelligence-based approach is used to train practicable models for business environment that enables effective prediction of software faults. eingereicht von Mag. Martin J. Schütz Abweichender Titel laut Übersetzung der Verfasserin/des Verfassers Masterarbeit Universität Linz 2023

Nutrients and herbivores are well-known drivers of grassland diversity and stability in local communities. However, whether they interact to impact the stability of aboveground biomass and whether these effects depend on spatial scales remain unknown. It is also unclear whether nutrients and herbivores impact stability via different facets of plant diversity including species richness, evenness, and changes in community composition through time and space. We used a replicated experiment adding nutrients and excluding herbivores for 5 years in 34 global grasslands to explore these questions. We found that both nutrient addition and herbivore exclusion alone reduced stability at the larger spatial scale (aggregated local communities; gamma stability), but through different pathways. Nutrient addition reduced gamma stability primarily by increasing changes in local community composition over time, which was mainly driven by species replacement. Herbivore exclusion reduced gamma stability primarily by decreasing asynchronous dynamics among local communities (spatial asynchrony). Their interaction weakly increased gamma stability by increasing spatial asynchrony. Our findings indicate that disentangling the processes operating at different spatial scales may improve conservation and management aiming at maintaining the ability of ecosystems to reliably provide functions and services for humanity.

Ecological models predict that the effects of mammalian herbivore exclusion on plant diversity depend on resource availability and plant exposure to ungulate grazing over evolutionary time. Using an experiment replicated in 57 grasslands on six continents, with contrasting evolutionary history of grazing, we tested how resources (mean annual precipitation and soil nutrients) determine herbivore exclusion effects on plant diversity, richness and evenness. Here we show that at sites with a long history of ungulate grazing, herbivore exclusion reduced plant diversity by reducing both richness and evenness and the responses of richness and diversity to herbivore exclusion decreased with mean annual precipitation. At sites with a short history of grazing, the effects of herbivore exclusion were not related to precipitation but differed for native and exotic plant richness. Thus, plant species’ evolutionary history of grazing continues to shape the response of the world’s grasslands to changing mammalian herbivory.

In the version of this Article originally published, there were unit conversion errors in the dataset when calculating specific leaf area (SLA) values at 10 of the 27 sites; errors were made when converting SLA from cm 2 g –1 to mm 2 g –1 and from mm 2 mg –1 to mm 2 g –1. This resulted in two incorrect data points: Phleum pratense in plot 27 at the Frue.ch site (SLA >300,000 mm 2 g –1) and Poa secunda in plot 31 at the shps.us site (SLA >60 mm 2 g –1). These two values were changed to ‘NA’ in the dataset, and therefore some reported estimates were changed, resulting in changes to the data points in Fig. 2a, the top bar of Fig. 3 and several values in the text.

Naturally occurring polysaccharide sulfates are highly diverse, owning variations in the backbone structure, linkage pattern and stereochemistry, branching diversity, sulfate content and positions of sulfate group(s). These structural characteristics bring about diverse sulfated polymers with dissimilar negative charge densities and structure–activity relationships. Herein, we start with a short discussion of techniques needed for extraction, purification, chemical sulfation, and structural characterization of polysaccharides. Processes of isolation and sulfation of plant-derived polysaccharides are challenging and usually involve two steps. In this context, we describe an integrated extraction-sulfation procedure that produces polysaccharide sulfates from natural products in one step, thereby generating additional pharmacological activities. Finally, we provide examples of the spectrum of natural source-derived polysaccharides possessing specific features of bioactivity, in particular focusing on current aspects of antiviral drug development and drug–target interaction. Thus, the review presents a detailed view on chemically engineered polysaccharides, especially sulfated derivatives, and underlines their promising biomedical perspectives.

The original version of this Article contained an error in the author affiliations. The affiliation of Martin Schütz with Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf, Switzerland was inadvertently omitted. Martin Schütz was incorrectly associated with Department of Forest Resources, University of Minnesota, Saint Paul, MN, US. This has now been corrected in both the PDF and HTML versions of the Article.

Background & aims: Herbivore-driven changes to soil properties can influence the decomposition rate of organic material and therefore soil carbon cycling within grassland ecosystems. We investigated how aboveground foraging mammalian and invertebrate herbivores affect mineral soil decomposition rates and associated soil properties in two subalpine vegetation types (short-grass and tall-grass) with different grazing histories. Methods: Using exclosures with differing mesh sizes, we progressively excluded large, medium and small mammals and invertebrates from the two vegetation types in the Swiss National Park (SNP). Mineral soil decomposition rates were assessed using the cotton cloth (standard substrate) method between May and September 2010. Results: Decomposition displayed strong spatio-temporal variability, best explained by soil temperature. Exclusion of large mammals increased decomposition rates, but further exclusion reduced decomposition rates again in the lightly grazed (tall-grass) vegetation. No difference among treatments was found in the heavily grazed (short-grass) vegetation. Heavily grazed areas had higher decomposition rates than the lightly grazed areas because of higher soil temperatures. Microbial biomass carbon and soil C:N ratio were also linked to spatio-temporal decomposition patterns, but not to grazing history. Conclusions: Despite altering some of the environmental controls of decomposition, cellulose decomposition rates in the SNP's subalpine grasslands appear to be mostly resistant to short-term herbivore exclusion.

Leaf traits are frequently measured in ecology to provide a ‘common currency’ for predicting how anthropogenic pressures impact ecosystem function. Here, we test whether leaf traits consistently respond to experimental treatments across 27 globally distributed grassland sites across 4 continents. We find that specific leaf area (leaf area per unit mass)—a commonly measured morphological trait inferring shifts between plant growth strategies—did not respond to up to four years of soil nutrient additions. Leaf nitrogen, phosphorus and potassium concentrations increased in response to the addition of each respective soil nutrient. We found few significant changes in leaf traits when vertebrate herbivores were excluded in the short-term. Leaf nitrogen and potassium concentrations were positively correlated with species turnover, suggesting that interspecific trait variation was a significant predictor of leaf nitrogen and potassium, but not of leaf phosphorus concentration. Climatic conditions and pretreatment soil nutrient levels also accounted for significant amounts of variation in the leaf traits measured. Overall, we find that leaf morphological traits, such as specific leaf area, are not appropriate indicators of plant response to anthropogenic perturbations in grasslands. Fil: Firn, Jennifer. Queensland University of Technology; Australia Fil: McGree, James M.. Queensland University of Technology; Australia Fil: Harvey, Eric. University of Montreal; Canadá Fil: Flores Moreno, Habacuc. University of Minnesota; Estados Unidos Fil: Schütz, Martin. Swiss Federal Institute for Forest, Snow and Landscape Research; Suiza Fil: Buckley, Yvonne M.. Trinity College; Irlanda Fil: Borer, Elizabeth T.. University of Minnesota; Estados Unidos Fil: Seabloom, Eric W.. University of Minnesota; Estados Unidos Fil: La Pierre, Kimberly J.. Smithsonian Environmental Research Center; Estados Unidos Fil: MacDougall, Andrew M.. University of Guelph; Canadá Fil: Prober, Suzanne M.. No especifíca; Fil: Stevens, Carly J.. Universidad de Lancaster; Reino Unido Fil: Sullivan, Lauren L.. University of Minnesota; Estados Unidos Fil: Porter, Erica. Queensland University of Technology; Australia Fil: Ladouceur, Emma. Helmholtz Center for Environmental Research; Alemania Fil: Allen, Charlotte. Queensland University of Technology; Australia Fil: Moromizato, Karine H.. Queensland University of Technology; Australia Fil: Morgan, John W.. La Trobe University; Australia Fil: Harpole, W. Stanley. Helmholtz Center for Environmental Research; Alemania. Universidad de Halle-Wittenberg ; Alemania Fil: Hautier, Yann. University of Utrecht; Países Bajos Fil: Eisenhauer, Nico. Universitat Leipzig; Alemania Fil: Wright, Justin P.. University of Duke; Estados Unidos Fil: Adler, Peter B.. State University of Utah; Estados Unidos Fil: Arnillas, Carlos Alberto. University of Toronto; Canadá Fil: Bakker, Jonathan D.. University of Washington; Estados Unidos Fil: Biederman, Lori. University of Iowa; Estados Unidos Fil: Broadbent, Arthur A. D.. University of Manchester; Reino Unido Fil: Brown, Cynthia S.. State University of Colorado at Boulder; Estados Unidos Fil: Bugalho, Miguel N.. Universidade Nova de Lisboa; Portugal Fil: Caldeira, Maria C.. Universidade Nova de Lisboa; Portugal Fil: Cleland, Elsa E.. University of California; Estados Unidos Fil: Ebeling, Anne. Universitat Jena; Alemania Fil: Fay, Philip A.. No especifíca; Fil: Hagenah, Nicole. Universidad de Pretoria; Sudáfrica Fil: Kleinhesselink, Andrew R.. University of California at Los Angeles; Estados Unidos Fil: Mitchell, Rachel. Arizona State University; Estados Unidos Fil: Moore, Joslin L.. Monash University; Australia Fil: Nogueira, Carla. Universidade Nova de Lisboa; Portugal Fil: Peri, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Santa Cruz. Universidad Tecnológica Nacional. Facultad Regional Santa Cruz. Centro de Investigaciones y Transferencia de Santa Cruz. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia de Santa Cruz; Argentina Fil: Roscher, Christiane. Helmholtz Center for Environmental Research; Alemania Fil: Smith, Melinda D.. State University of Colorado at Boulder; Estados Unidos Fil: Wragg, Peter D.. University of Minnesota; Estados Unidos Fil: Risch, Anita C.. No especifíca

Grasslands are subject to considerable alteration due to human activities globally, including widespread changes in populations and composition of large mammalian herbivores and elevated supply of nutrients. Grassland soils remain important reservoirs of carbon (C) and nitrogen (N). Herbivores may affect both C and N pools and these changes likely interact with increases in soil nutrient availability. Given the scale of grassland soil fluxes, such changes can have striking consequences for atmospheric C concentrations and the climate. Here, we use the Nutrient Network experiment to examine the responses of soil C and N pools to mammalian herbivore exclusion across 22 grasslands, under ambient and elevated nutrient availabilities (fertilized with NPK + micronutrients). We show that the impact of herbivore exclusion on soil C and N pools depends on fertilization. Under ambient nutrient conditions, we observed no effect of herbivore exclusion, but under elevated nutrient supply, pools are smaller upon herbivore exclusion. The highest mean soil C and N pools were found in grazed and fertilized plots. The decrease in soil C and N upon herbivore exclusion in combination with fertilization correlated with a decrease in aboveground plant biomass and microbial activity, indicating a reduced storage of organic matter and microbial residues as soil C and N. The response of soil C and N pools to herbivore exclusion was contingent on temperature – herbivores likely cause losses of C and N in colder sites and increases in warmer sites. Additionally, grasslands that contain mammalian herbivores have the potential to sequester more N under increased temperature variability and nutrient enrichment than ungrazed grasslands. Our study highlights the importance of conserving mammalian herbivore populations in grasslands worldwide. We need to incorporate local‐scale herbivory, and its interaction with nutrient enrichment and climate, within global‐scale models to better predict land–atmosphere interactions under future climate change., Global Change Biology, 26 (4), ISSN:1354-1013, ISSN:1365-2486

Our understanding of carbon (C) dynamics within savannas is very limited, especially how source/sink dynamics are influenced by the resident biota. Previous measurements of epigeal termite mounds (termitaria), ubiquitous in many savannas, have shown that they are considerable point sources of soil carbon dioxide (CO2), whereas CO2 measurements collected outside the mounds were generally assumed to be independent of termite activity. However, no measurements were conducted along gradients away from the mounds to confirm this. We quantified daytime soil CO2 emissions (soil respiration) along gradients from the center to 20m from the mound edge in Serengeti National Park, and measured soil temperature/moisture, macro-invertebrate abundance, and vegetation height as variables potentially influencing these emissions. Further, we quantified how far into the savanna termitaria impact CO2 emissions. As in other studies, we found the highest soil CO2 fluxes at the termitaria-center and considerably lower fluxes in the surrounding savanna. Macro-invertebrate abundance was associated with the differences in emissions measured, whereas the other variables were not. The analysis of spatial autocorrelation revealed significantly lower fluxes between the termitaria edge and up to 9m from the edge compared to the values measured at the termitaria-center and between 10 and 20m from the termitaria edge. When extrapolating the emissions across the landscape our results suggest that the lower CO2 emissions found between the edge and 9m fully compensate for the high fluxes measured at the termitaria center. Consequently, our findings provide evidence that termitaria might influence the savanna C source-sink dynamics differently than previously thought

We examined the role of red deer (Cervus elaphus L.) in translocating phosphorus (P) from their preferred grazing sites (short-grass vegetation on subalpine grasslands) to their wider home range in a subalpine grassland ecosystem in the Central European Alps. Phosphorus was used because it is the limiting nutrient in these grasslands. When we compared P removal of aboveground biomass due to grazing with P input due to the deposit of feces on a grid of 268 cells (20 m × 20 m) covering the entire grassland, we detected distinct spatial patterns: the proportion of heavily grazed short-grass vegetation increased with increasing soil-P pool, suggesting that red deer preferably grazed on grid cells with a higher soil-P pool. Biomass consumption related to increased proportion of short-grass vegetation, and therefore P removal, increased with increasing soil-P pool. However, within the two vegetation types (short-grass and tall-grass), consumption was independent from soil-P pool. In addition, P input rates from defecation increased with increasing soil-P pool, resulting in a constant mean net P loss of 0.083 kg ha−1 y−1 (0.03%-0.07% of soil-P pool) independent of both soil-P pool and vegetation type. Thus, there was no P translocation between grid cells with different soil-P pools or between short-grass and tall-grass vegetation. Based on these results, it is likely that the net rate of P loss is too small to explain the observed changes in vegetation composition from tall-herb/meadow communities to short-grass and from tall-grass to short-grass on the grassland since 1917. Instead, we suggest that the grazing patterns of red deer directly induced succession from tall-herb/meadow communities to short-grass vegetation. Yet, it is also possible that long-term net soil-P losses indirectly drive plant succession from short-grass to tall-grass vegetation, because nutrient depletion could reduce grazing pressure in short-grass vegetation and enable the characteristic tall-grass species Carex sempervirens Vill. to establish

Grasslands support large populations of herbivores and store up to 30% of the world's soil carbon (C). Thus, herbivores likely play an important role in the global C cycle. However, most studies on how herbivory impacts the largest source of C released from grassland soils—soil carbon dioxide (CO2) emissions—only considered the role of large ungulates. This ignores all other vertebrate and invertebrate herbivores and their collective effects on ecosystem properties. We progressively excluded large, medium, and small vertebrates and invertebrates from two subalpine grasslands (productive, heavily grazed short-grass; less productive, lightly grazed tall-grass) using size-selective fences, assessed the impact on soil CO2 emissions and related biotic and abiotic variables. Exclusion resulted in significant changes in soil CO2 emissions in both vegetation types. Short-grass soil CO2 emissions progressively increased when large and medium mammals were excluded. However, no difference was detected among plots were all or no herbivores grazed. In contrast, tall-grass soil CO2 emissions were not affected by mammal exclusion, but excluding all herbivores lead to reduced emissions. Soil micro-climatic parameters best predicted the patterns of soil CO2 emissions in short-grass vegetation, whereas root biomass was the best predictor of CO2 release in tall-grass vegetation. Our results showed that diverse herbivore communities affect soil respiration differently than assumed from previous studies that only excluded large ungulates. Such information is important if we are to understand how changes in herbivore species composition—as could happen through altered management practices, extinction or invasion—impact grassland C storage and release

Black phosphorus (black-P) consists of phosphorene sheets, stacked by van der Waals dispersion. In a recent study based on periodic local second-order Møller-Plesset perturbation theory (LMP2) with higher-order corrections evaluated on finite clusters, we obtained a value of −151 meV/atom for the exfoliation energy. This is almost twice as large as another recent theoretical result (around −80 meV/atom) obtained with quantum Monte Carlo (QMC). Here, we revisit this system on the basis of the recently implemented, periodically embedded ring coupled cluster (rCCD) model instead of LMP2. Higher-order coupled cluster corrections on top of rCCD are obtained from finite clusters by utilizing our new "unit-cell-in-cluster" scheme. Our new value of −92 meV/atom is noticeably lower than that based on LMP2 and in reasonably close agreement with the QMC result. However, in contrast to QMC, no strong effect from the second-neighbor and farther layers in black-P are observed in our calculations.

Fraser et al. (Reports, 17 July 2015, p. 302) report a unimodal relationship between productivity and species richness at regional and global scales, which they contrast with the results of Adler et al. (Reports, 23 September 2011, p. 1750). However, both data sets, when analyzed correctly, show clearly and consistently that productivity is a poor predictor of local species richness.

Electron spins confined in quantum dots (QDs) are among the leading contenders for implementing quantum information processing. In this Thesis we address two of the most significant technological challenges towards developing a scalable quantum information processor based on spins in quantum dots: (i) decoherence of the electronic spin qubit due to the surrounding nuclear spin bath, and (ii) long-range spin-spin coupling between remote qubits. To this end, we develop novel strategies that turn the unavoidable coupling to the solid-state environment (in particular, nuclear spins and phonons) into a valuable asset rather than a liability. In the first part of this Thesis, we investigate electron transport through single and double QDs, with the aim of harnessing the (dissipative) coupling to the electronic degrees of freedom for the creation of coherence in both the transient and steady-state behaviour of the ambient nuclear spins. First, we theoretically show that intriguing features of coherent many-body physics can be observed in electron transport through a single QD. To this end, we first develop a master-equation-based formalism for electron transport in the Coulomb-blockade regime assisted by hyperfine (HF) interaction with the nuclear spin ensemble in the QD. This general tool is then used to study the leakage current through a single QD in a transport setting. When starting from an initially uncorrelated, highly polarized state, the nuclear system experiences a strong correlation buildup, due to the collective nature of the coupling to the central electron spin. We demonstrate that this results in a sudden intensity burst in the electronic tunneling current emitted from the QD system, which exceeds the maximal current of a corresponding classical system by several orders of magnitude. This gives rise to the new paradigm of electronic superradiance. Second, building upon the insight that the nuclear spin dynamics are governed by collective interactions giving rise to coherent effects such as superradiance, we propose a scheme for the deterministic generation of steady-state entanglement between the two nuclear spin ensembles in an electrically defined double quantum dot. Because of quantum interference in the collective coupling to the electronic degrees of freedom, the nuclear system is actively driven into a two-mode squeezedlike target state. The entanglement buildup is accompanied by a self-polarization of the nuclear spins towards large Overhauser field gradients. Moreover, the feedback between the electronic and nuclear dynamics is shown to lead to intriguing effects such as multistability and criticality in the steady-state solutions. In the second part of this Thesis, our focus turns towards the realization of long-range spin-spin coupling between remote qubits. We propose a universal, on-chip quantum transducer based on surface acoustic waves in piezo-active materials. Because of the intrinsic piezoelectric (and/or magnetostrictive) properties of the material, our approach provides a universal platform capable of coherently linking a broad array of qubits, including quantum dots, trapped ions, nitrogen-vacancy centers or superconducting qubits. The quantized modes of surface acoustic waves lie in the gigahertz range, can be strongly confined close to the surface in phononic cavities and guided in acoustic waveguides. We show that this type of surface acoustic excitations can be utilized efficiently as a quantum bus, serving as an on-chip, mechanical cavity-QED equivalent of microwave photons and enabling long-range coupling of a wide range of qubits. In summary, this thesis provides contributions towards developing a scalable quantum information processor based on spins in quantum dots in two different aspects. The first part is dedicated to a deeper understanding of the nuclear spin dynamics in quantum dots. In the second part we put forward a novel sound-based strategy to realize long-range spin-spin coupling between remote qubits. This completes a broad picture of spin-based quantum information processing which integrates different perspectives, ranging from the single-qubit level to a broader quantum network level., Elektronenspins in Quantenpunkten gehören zu den vielversprechendsten Ansätzen für die erfolgreiche Implementierung von Quanteninformationsverarbeitung. Diese Arbeit behandelt zwei der größten Herausforderungen für die Entwicklung eines skalierbaren Quanteninformationsprozessors auf Basis von Spins in Quantenpunkten: (i) die Kontrolle der Dekohärenz des elektronischen Spins aufgrund der Wechselwirkung mit dem umliegenden Kernspin-Bad, und (ii) die Realisierung einer langreichweitigen Spin-Spin Kopplung zwischen entfernt liegenden Qubits. Zu diesem Zweck entwickeln wir neue Strategien, die die unvermeidliche Kopplung an die Festkörperumgebung (insbesondere Kernspins und Phononen) zu ihrem Vorteil ausnutzen. Im ersten Teil dieser Arbeit untersuchen wir den Elektronentransport durch Einzel- und Doppel-Quantenpunkte, mit dem Ziel die dissipative Kopplung an die elektronischen Freiheitsgrade zur Erzeugung von kohärenter Kernspindynamik auszunutzen. Dies gilt sowohl für das kurzfristige wie auch das langfristige Verhalten der Kernspins. Zunächst zeigen wir theoretisch, dass faszinierende Eigenschaften kohärenter Vielteilchenphysik im Elektronen-transport durch einen einzelnen Quantenpunkt beobachtet werden können. Dazu entwickeln wir zunächst einen auf Master-Gleichungen basierenden Formalismus für den Elektronentransport im Coulomb-Blockade Regime, der die Hyperfeinwechselwirkung mit dem Kernspin-Ensemble im Quantenpunkt berücksichtigt. Dieses allgemeine theoretische Werkzeug wird anschließend verwendet, um den Strom durch einen einzelnen Quantenpunkt in einem Transportszenario zu studieren. Sind die Kernspins anfänglich in einem unkorrelierten, hoch polarisierten Zustand, so bauen sich aufgrund der kollektiven Wechselwirkung mit dem zentralen Elektronenspin starke Korrelationen zwischen den Kernspins auf. Wir zeigen, dass dies zu einem plötzlichen, starken Anstieg im Tunnelstrom durch den Quantenpunkt führt, welcher den maximalen Strom in einem analogen klassischen System um mehrere Größenordnungen übersteigt. Dieses Verhalten begründet das neue Paradigma von elektronischer Superradianz. Ausgehend von der Einsicht, dass die Kernspindynamik von kollektiven Wechselwirkungen bestimmt wird, welche wiederum zu kohärenten Effekten wie Superradianz führen können, schlagen wir im nächsten Schritt ein Modell zur deterministischen Verschränkungserzeugung zwischen den beiden Kernspinensembles in einem elektrisch definierten Doppelquantenpunkt vor. Aufgrund von Quanteninterferenz in der kollektiven Kopplung an die elektronischen Freiheitsgrade wird das Kernspinsystem aktiv in einen gequetschten zwei-Moden Zustand gepumpt. Der Aufbau von Verschränkung wird durch einen Polarisationsprozess der Kernspins hin zu großen Overhauser-Feldern begleitet. Darüber hinaus wird gezeigt, dass die Rückkopplung zwischen elektronischen und Kernspin-Freiheitsgraden zu interessanten Effekten wie zum Beispiel Multistabilität und kritischem Verhalten in den stationären Lösungen führt. Im zweiten Teil der Arbeit wenden wir uns der langreichweitigen Spin-Spin Kopplung zwischen entfernt liegenden Qubits zu. Dazu schlagen wir einen universellen Quanten-Transducer vor, der auf akustischen Oberflächenwellen in piezo-aktiven Materialen beruht und direkt auf Chips aufgebracht werden kann. Aufgrund der piezo-elektrischen (und/oder magnetostriktiven) Eigenschaften des Materials bietet unser Ansatz eine universelle Platform für eine ganze Reihe von Qubits; dazu gehören Quantenpunkte, Ionen, Stickstoff-Fehlstellen-Zentren (NV-Zentren) oder auch supraleitende Qubits. Die quantisierten Moden der akustischen Oberflächenwellen haben typische Frequenzen im Gigahertz-Bereich, können stark in der Nähe der Oberfläche in phononischen Resonatoren lokalisiert werden und entlang akustischer Wellenleiter geleitet werden. Wir zeigen, dass diese Art der akustischen Oberflächenanregung effizient als Quanten-Bus verwendet werden kann, der als mechanisches Analogon zu Mikrowellen-Photonen in der Resonator-Quanten-Elektrodynamik fungiert und langreichweitige Kopplung zwischen entfernt liegenden Qubits ermöglicht. Zusammenfassend liefert diese Arbeit einen Beitrag zur Entwicklung eines skalierbaren, auf Spins in Quantenpunkten beruhenden Quanteninformationsprozessors aus zwei verschiedenen Perspektiven. Der erste Teil widmet sich eines tiefgehenderen Verständnisses der Kernspin-dynamik in Quantenpunkten. Im zweiten Teil schlagen wir eine neue, auf Schall basierende Strategie zur Erzeugung von langreichweitiger Spin-Spin Kopplung zwischen entfernt liegenden Qubits vor. Dies vervollständigt ein breites Bild von Spin-basierter Quanteninformationsverarbeitung, welches verschiedene Perspektiven vereinigt, von der Ebene einzelner Qubits bis hinzu einer umfassenderen Ebene eines Quanten-Netzwerks.

The thesis deals with design of new processes of business department in IT company which provides server hosting, web hosting and domain registration services. These processes come from identification and analysis of current processes and the theory of business department management. Key Performance Indicators (KPIs) were set for selected processes which can be used for managing the company as a whole. Models of processes were created due to EPC notation. New processes were designed to continuously create data in CRM information system providing evidential and information support necessary for business department management, including the possibility of measuring its performance. Processes also automatize often repetitive activities and provide relevant information to other affected business units within the company. Contribution of the thesis lies in results of analysis of current identified processes containing solution proposals of discovered problems and newly created process models. Both can be used as a pattern for optimization of current processes in already existing organization or for designing new process models in new organization in the same or similar field of business.

Heat shock protein 70 (Hsp70) is frequently overexpressed in tumor cells. An unusual cell surface localization could be demonstrated on a large variety of solid tumors including lung, colorectal, breast, squamous cell carcinomas of the head and neck, prostate and pancreatic carcinomas, glioblastomas, sarcomas and hematological malignancies, but not on corresponding normal tissues. A membrane (m)Hsp70-positive phenotype can be determined either directly on single cell suspensions of tumor biopsies by flow cytometry using cmHsp70.1 monoclonal antibody or indirectly in the serum of patients using a novel lipHsp70 ELISA. A mHsp70-positive tumor phenotype has been associated with highly aggressive tumors, causing invasion and metastases and resistance to cell death. However, natural killer (NK), but not T cells were found to kill mHsp70-positive tumor cells after activation with a naturally occurring Hsp70 peptide (TKD) plus low dose IL-2 (TKD/IL-2). Safety and tolerability of ex vivo TKD/IL-2 stimulated, autologous NK cells has been demonstrated in patients with metastasized colorectal and non-small cell lung cancer (NSCLC) in a phase I clinical trial. Based on promising clinical results of the previous study, a phase II randomized clinical study was initiated in 2014. The primary objective of this multicenter proof-of-concept trial is to examine whether an adjuvant treatment of NSCLC patients after platinum-based radiochemotherapy (RCTx) with TKD/IL-2 activated, autologous NK cells is clinically effective. As a mHsp70-positive tumor phenotype is associated with poor clinical outcome only mHsp70-positive tumor patients will be recruited into the trial. The primary endpoint of this study will be the comparison of the progression-free survival of patients treated with ex vivo activated NK cells compared to patients who were treated with RCTx alone. As secondary endpoints overall survival, toxicity, quality-of-life, and biological responses will be determined in both study groups.

Hintergrund und Fragestellung: Ziel der Studie war es, zu evaluieren welche diagnostischen und therapeutischen Konsequenzen aus den Ultraschallbefunden unserer Klinik gezogen wurden. Patienten und Methodik: Zwischen Anfang März 2004 und Ende Februar 2005 wurden im interdisziplinären Ultraschallzentrum der Universität Regensburg insgesamt 14 301 Ultraschalluntersuchungen durchgeführt. 1162 zufällig ausgewählte Untersuchungen und deren Befunde wurden im Rahmen der Studie nachverfolgt. Die Untersucher dokumentierten die Befunde im hausüblichen standardisierten Befundungsmodus. Im weiteren Verlauf wurde anhand der Patientenakte und des Entlassbriefes des jeweiligen Patienten evaluiert, welche diagnostischen und therapeutischen Konsequenzen aus den Befunden gezogen wurden. Ergebnisse: Insgesamt zeigten sich 1843 pathologische Befunde bei 901 Patienten. In 114 Fällen (6,2 %) wurde keine adäquate Abklärung durchgeführt oder im Entlassbrief empfohlen, wobei die Entscheidung hierzu nicht nachvollziehbar war (Wertung 4). Die Patienten für diese Erhebung wurden zu großen Anteilen (72,1 %) aus den internistischen Abteilungen/Kliniken rekrutiert. Der höchste abteilungsabhängige Anteil an pathologischen Befunden mit Wertung 4 fand sich dagegen in den Kliniken/Abteilungen für Mund-Kiefer-Gesichtschirurgie (MKG), Dermatologie und Nuklearmedizin. Folgerungen: Zusammenfassend halten die Autoren eine Gesamtzahl von 6,2 % an Befunden, die nicht die entsprechenden Konsequenzen nach sich zogen, für relativ niedrig. Möglicherweise kann diese Zahl jedoch durch weitere Verbesserung der Formulierungen in den Untersuchungsbefunden noch deutlich gesenkt werden., Background and objective: The aim of this study was to evaluate the diagnostic and therapeutic consequences arising from abnormal ultrasound findings in a multidisciplinary setting in the University of Regensburg Clinical Centre. Patients and methods: The results of 1162 randomly selected ultrasound examinations (on 671 males and 491 females) from a total of 14 301 at an interdisciplinary ultrasound unit were analysed. The investigators recorded the findings in a routinely used standardized manner. The records and discharge reports of each patient were then evaluated with regard to the diagnostic and therapeutic consequences of the findings. Results: There were 1843 abnormal findings in 901 patients. In 114 patients (6.2 %) no adequate diagnostic measures had been undertaken or recommended at discharge, but the reasons for the decisions taken could not be judged (value 4). 72.1 % of all patients were recruited from departments of internal medicine. However, the highest percentage of findings without adequate consequences were found to be in patients of the departments of oral and maxillofacial surgery, dermatology and nuclear medicine. Conclusion: The number of ultrasound examinations that had been done without adequate consequences was comparatively low at 6.2 %. But perhaps this number can be further reduced by improved wording of the examination reports.

This project is aimed at investigating trophic cascades originating from the successive exclusion of herbivores of various sizes from subalpine grasslands of the Swiss National Park (SNP). Historical grazing patterns in the SNP have developed two distinct vegetation types – heavily grazed short grass vegetation and lightly grazed tall grass vegetation – derived from former land use which differ in vegetation quality, community composition and usage by herbivores. This poster presents some of the methods we use to study how herbivore exclusion affects ecosystem properties and processes.

Although diverse herbivore communities utilise grasslands, many previous studies only excluded the largest animals. Thus, little is known about how smaller herbivores, including invertebrates, affect grassland processes. We find that sequentially excluding different sized herbivores strongly impacts soil properties such as moisture, temperature and respiration. Such changes have potential implications for ecosystem nutrient cycling (e.g. C storage). This poster was presented at the British Ecological Society 2012 Annual Meeting in Birmingham between the 17th and 20th December.

Although diverse herbivore communities utilise grasslands, many previous studies only exclude largest animals. Thus, little is known about how smaller herbivores, including invertebrates, affect grassland processes. We find that sequentially excluding different sized herbivores strongly impacts vegetation quantity/quality; depending on original grassland grazing pressures. This has implications for ecosystem nutrient cycling (e.g. C storage) and pattern reinforcing feedbacks. This presentation was presented at the British Ecological Society Annual Meeting 2012 on the 18th December.

In order to understand how different herbivore guilds based on body size affect ecosystem processes, we designed an experimental setup in the Swiss Alps. Using differing mesh sizes we sequentially exclude large herbivores (ungulates), medium mammals (hare and marmots), small mammals (mice and voles) and small herbivores (invertebrates). The fencing method has the potential to change ecosystem parameters such as air humidity and temperature, soil moisture and temperature and light levels. This is a supplement to go with the poster "Does size matter? Effects of herbivore exclusion on soil properties" presented at the British Ecological Society 2012 Annual Meeting in Birmingham between the 17th and 20th of December.

Mitosis is the essential process during which a cell divides into two viable daughter cells. To allow a faithful segregation of the chromosomes into each daughter, the cell forms the bipolar spindle. The NIMA-like kinase family member Nek9 has been previously proposed to play a role in bipolar spindle assembly and in the chromosomal pathway of microtubule assembly. We aimed at gaining a better understanding of Nek9 function by characterizing Xenopus Nek9, xNek9, using the Xenopus egg extract system. We have shown that xNek9 may not act through the kinase cascade xNek9 – xNek6 in meiosis as described for human Nek9 in somatic cells and therefore may have different substrates. Furthermore, we have demonstrated by depletion, increased addition of Flag-hNek9 and a dominant-negative approach that xNek9 is important for bipolar spindle formation. In addition, we have shown that xNek9 depletion causes decreased microtubule density in bipolar spindles and slower RanGTP induced aster formation. We identified xNedd1, the adaptor protein for the γTuRC, as a novel interactor and substrate of xNek9. xNek9 depletion reduces the recruitment of xNedd1 to sperm nuclei induced aster and decreases the number and length of nucleated microtubules. These data suggest that one role of xNek9 in spindle assembly is exerted through xNedd1 regulation. We propose a model for xNek9 – xNedd1 interaction and a putative mechanism for the regulation of xNek9 – xNedd1 explaining how they fulfil their role in bipolar spindle assembly., La mitosis es el proceso esencial durante el cual una célula se divide en dos células hijas viables. Para permitir una segregación fiable de los cromosomas en cada hija, la célula forma el huso bipolar. Nek9, el miembro de la familia de quinasas NIMA-like ha sido propuesto para desempeñar un papel en el la asamblea del huso bipolar y en la vía cromosómica de ensamblaje de los microtúbulos. Nuestro objetivo era lograr una mejor comprensión de la función Nek9 caracterizando Nek9 de Xenopus, xNek9, utilizando el sistema de extracto de huevos de Xenopus. Hemos demostrado que xNek9 probablemente no actuará a través de la cascada de las quinasas xNek9 - xNek6 en la meiosis como se describe para Nek9 humano en células somáticas y por lo tanto pueden tener diferentes sustratos. Además, hemos demostrado por el agotamiento, la adición incrementada de Flag-hNek9 y un enfoque dominante-negativas que xNek9 es importante para la formación del huso bipolar. Además, hemos demostrado que el agotamiento xNek9 causa una disminución de la densidad de los microtúbulos en los husos bipolares y una formación más lenta de asteres inducidos por RanGTP. Se identificó xNedd1, la proteína adaptadora para el γTuRC, como un interactor y sustrato novedoso de xNek9. El agotamiento de xNek9 reduce la contratación de xNedd1 a los asteres inducidas por núcleos de espermatozoides y disminuye el número y longitud de microtúbulos nucleados. Estos datos sugieren que un papel de xNek9 en el conjunto del huso se husorce a través de la regulación de xNedd1. Proponemos un modelo para la interacción xNek9 – xNedd1 y un supuesto mecanismo para la regulación de xNek9 – xNedd1 explicando cómo cumplen su papel en la ensamblaje del huso bipolar.