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Today, diverse communities of zooxanthellate corals thrive, but do not build reef, under a wide range of environmental conditions. In these settings they inhabit natural bottom communities, sometimes forming patch-reefs, coral carpets and knobs. Episodes in the fossil record, characterized by limited coral-reef development but widespread occurrence of coral-bearing carbonates, may represent the fossil analogs of these non-reef building, zooxanthellate coral communities. If so, the study of these corals could have valuable implications for paleoenvironmental reconstructions. Here we focus on the evolution of early Paleogene corals as a fossil example of coral communities mainly composed by zooxanthellate corals (or likely zooxanthellate), commonly occurring within carbonate biofacies and with relatively high diversity but with a limited bioconstructional potential as testified by the reduced record of coral reefs. We correlate changes of bioconstructional potential and community compositions of these fossil corals with the main ecological/environmental conditions at that time. The early Paleogene greenhouse climate was characterized by relatively short pulses of warming with the most prominent occurring at the Paleocene-Eocene boundary (PETM event), associated with high weathering rates, nutrient fluxes, and pCO(2) levels. A synthesis of coral occurrences integrated with our data from the Adriatic Carbonate Platform (SW Slovenia) and the Minervois region (SW France), provides evidence for temporal changes in the reef-building capacity of corals associated with a shift in community composition toward forms adapted to tolerate deteriorating sea-water conditions. During the middle Paleocene coral-algal patch reefs and barrier reefs occurred from shallow-water settings, locally with reef-crest structures. A first shift can be traced from middle Paleocene to late Paleocene, with small coral-algal patch reefs and coral-bearing mounds development in shallow to intermediate water depths. In these mounds corals were highly subordinated as bioconstructors to other groups tolerant to higher levels of trophic resources (calcareous red algae, encrusting foraminifera, microbes, and sponges). A second shift occurred at the onset of the early Eocene with a further reduction of coral framework-building capacity. These coral communities mainly formed knobs in shallow-water, turbid settings associated with abundant foraminiferal deposits. We suggest that environmental conditions other than high temperature determined a combination of interrelated stressors that limited the coral-reef construction. A continuous enhancement of sediment load/nutrients combined with geochemical changes of ocean waters likely displaced corals as the main bioconstructors during the late Paleocene-early Eocene times. Nonetheless, these conditions did not affect the capacity of some corals to colonize the substrate, maintain biodiversity, and act as locally important carbonate-sediment producers, suggesting broad environmental tolerance limits of various species of corals. The implications of this study include clues as to how both ancient and modern zooxanthellate corals could respond to changing climate.
Autoritarismus : Einführung
(2012)
Taking advantage of ATRP and using functionalized initiators, different functionalities were introduced in both α and ω chain-ends of synthetic polymers. These functionalized polymers could then go through modular synthetic pathways such as click cycloaddition (copper-catalyzed or copper-free) or amidation to couple synthetic polymers to other synthetic polymers, biomolecules or silica monoliths. Using this general strategy and designing these co/polymers so that they are thermoresponsive, yet bioinert and biocompatible with adjustable cloud point values (as it is the case in the present thesis), the whole generated system becomes "smart" and potentially applicable in different branches. The applications which were considered in the present thesis were in polymer post-functionalization (in situ functionalization of micellar aggregates with low and high molecular weight molecules), hydrophilic/hydrophobic tuning, chromatography and bioconjugation (enzyme thermoprecipitation and recovery, improvement of enzyme activity). Different α-functionalized co/polymers containing cholesterol moiety, aldehyde, t-Boc protected amine, TMS-protected alkyne and NHS-activated ester were designed and synthesized in this work.
The aim of this thesis is the quantum dynamical study of two examples of scanning tunneling microscope (STM)-controllable, Si(100)(2x1) surface-mounted switches of atomic and molecular scale. The first example considers the switching of single H-atoms between two dangling-bond chemisorption sites on a Si-dimer of the Si(100) surface (Grey et al., 1996). The second system examines the conformational switching of single 1,5-cyclooctadiene molecules chemisorbed on the Si(100) surface (Nacci et al., 2008). The temporal dynamics are provided by the propagation of the density matrix in time via an according set of equations of motion (EQM). The latter are based on the open-system density matrix theory in Lindblad form. First order perturbation theory is used to evaluate those transition rates between vibrational levels of the system part. In order to account for interactions with the surface phonons, two different dissipative models are used, namely the bilinear, harmonic and the Ohmic bath model. IET-induced vibrational transitions in the system are due to the dipole- and the resonance-mechanism. A single surface approach is used to study the influence of dipole scattering and resonance scattering in the below-threshold regime. Further, a second electronic surface was included to study the resonance-induced switching in the above-threshold regime. Static properties of the adsorbate, e.g., potentials and dipole function and potentials, are obtained from quantum chemistry and used within the established quantum dynamical models.
The switching of single cyclooctadiene molecules chemisorbed on a Si(100) surface between two stable conformations, can be achieved with a scanning tunneling microscope [Nacci , Phys. Rev. B 77, 121405(R) (2008)]. Recently, it was shown by quantum chemical and quantum dynamical simulations that major experimental facts can be explained by a single-mode model with switching enforced by inelastic electron tunneling (IET) excitations and perturbed by vibrational relaxation [Nacci , Nano Lett. 9, 2997 (2009)]. In the present paper, we extend the previous theoretical work in several respects: (1) The model is generalized to a two-mode description in which two C2H4 units of COD can move independently; (2) contributions of dipole and, in addition, (cation and anion) resonance-IET rates are considered; (3) the harmonic-linear vibrational relaxation model used previously is generalized to anharmonic vibrations. While the present models highlight generic aspects of IET-switching between two potential minima, they also rationalize specific experimental findings for COD/Si(100): (1) A single-electron excitation mechanism with a linear dependence of the switching rate on tunneling current I, (2) the capability to switch both at negative and positive sample biases, and (3) a crossover temperature around similar to 60 K from an IET-driven, T-independent atom tunneling regime, to classical over-the-barrier isomerization with exponential T-dependence at higher temperatures for a bias voltage of +1.5 V and an average tunneling current of 0.73 nA.
The scanning tunnelling microscope (STM)-induced switching of a single cyclooctadiene molecule between two stable conformations chemisorbed on a Si(100) surface is investigated using an above threshold model including a neutral ground state and an ionic excited state potential. Switching was recently achieved experimentally with an STM operated at cryogenic temperatures (Nacci et al 2008 Phys. Rev. B 77 121405(R)) and rationalized by a below threshold model using just a single potential energy surface (Nacci et al 2009 Nano Lett. 9 2997).
In the present paper, we show that experimental key findings on the inelastic electron tunnelling (IET) switching can also be rationalized using an above threshold density matrix model, which includes, in addition to the neutral ground state potential, an anionic or cationic excited potential. We use one and two-dimensional potential energy surfaces. Furthermore, the influence of two key parameters of the density matrix description, namely the electronic lifetime of the ionic resonance and the vibrational lifetimes, on the ground state potential are discussed.
A multi-proxy study including analyses of delta C-13(org) for the lake sediment core GN-02 and grain size, TOC. CaCO3 content, delta C-13(carb) and delta O-18(carb) of bulk carbonate, and the mineralogy of the parallel core GN-04 from Gun Nuur was performed to reconstruct the Holocene hydrology and climate on the northern Mongolian Plateau. The chronology was established using 40 C-14 dates of bulk organic matter in addition to nine previously published radiocarbon dates for core GN-02, and further five C-14 dates for the new core GN-04. A lake reservoir effect of 1060 C-14 years was determined as the intercept of the high-resolution GN-02 age-depth model at the modern sediment surface. The size of the reservoir effect is supported by the age of the core-top sample (1200 +/- 40 C-14 years) and the determined difference between a wood-derived radiocarbon age from the GN-02 core base and the age-model inferred age for bulk organic matter at the same stratigraphic level (1000 C-14 years). Low lake level and prevailing aeolian sediment deposition at Gun Nuur under dry conditions were recorded during the earliest Holocene (> 10,800-10,300 cal a BP). Gun Nuur expanded under significantly wetter conditions between 10,300 and 7000 cal a BP. Unstable climate conditions existed in the mid Holocene (7000-2500 cal a BP) and three periods of low lake-levels and significantly drier conditions were recorded between 7000-5700, 4100-3600 and 3000-2500 cal a BP. Intermediate lake levels were inferred for the intervening periods. Around 2500 cal a BP, the climate change and wetter conditions were established again. As a consequence, the lake level of Gun Nuur rose again due to higher effective moisture and the relatively wet present conditions were achieved ca. 1600 cal a BP. Our results suggest that the initial Holocene climate change on the northern Mongolian Plateau was not accompanied by a rapid increase in precipitation as on the Tibetan Plateau. The establishment of wetter conditions in northern Mongolia lagged behind the early Holocene moisture increase on the Tibetan Plateau by ca. 1000 years. Subsiding dry air in the north of the Tibetan Plateau resulted from the strengthened summer monsoon on the Tibetan Plateau during the period of maximum summer insolation and probably inhibited a significant precipitation increase in Mongolia. The significant moisture increase in the Gun Nuur region at ca. 10.3 cal ka BP is probably not related to the northward shift of the present summer monsoon boundary or the moisture delivery from the northern Atlantic through the westerlies. Instead, water from melting snow, ice and frozen ground and the generation of precipitation from the local recycling of moisture are discussed as possible moisture source for the early onset of wetter conditions on the Mongolian Plateau.
The most crucial step in data processing from high-throughput sequencing applications is the accurate and sensitive alignment of the sequencing reads to reference genomes or transcriptomes. The accurate detection of insertions and deletions (indels) and errors introduced by the sequencing platform or by misreading of modified nucleotides is essential for the quantitative processing of the RNA-based sequencing (RNA-Seq) datasets and for the identification of genetic variations and modification patterns. We developed a new, fast and accurate algorithm for nucleic acid sequence analysis, FANSe, with adjustable mismatch allowance settings and ability to handle indels to accurately and quantitatively map millions of reads to small or large reference genomes. It is a seed-based algorithm which uses the whole read information for mapping and high sensitivity and low ambiguity are achieved by using short and non-overlapping reads. Furthermore, FANSe uses hotspot score to prioritize the processing of highly possible matches and implements modified Smith-Watermann refinement with reduced scoring matrix to accelerate the calculation without compromising its sensitivity. The FANSe algorithm stably processes datasets from various sequencing platforms, masked or unmasked and small or large genomes. It shows a remarkable coverage of low-abundance mRNAs which is important for quantitative processing of RNA-Seq datasets.
To provide physically based wind modelling for wind erosion research at regional scale, a 3D computational fluid dynamics (CFD) wind model was developed. The model was programmed in C language based on the Navier-Stokes equations, and it is freely available as open source. Integrated with the spatial analysis and modelling tool (SAMT), the wind model has convenient input preparation and powerful output visualization. To validate the wind model, a series of experiments was conducted in a wind tunnel. A blocking inflow experiment was designed to test the performance of the model on simulation of basic fluid processes. A round obstacle experiment was designed to check if the model could simulate the influences of the obstacle on wind field. Results show that measured and simulated wind fields have high correlations, and the wind model can simulate both the basic processes of the wind and the influences of the obstacle on the wind field. These results show the high reliability of the wind model. A digital elevation model (DEM) of an area (3800 m long and 1700 m wide) in the Xilingele grassland in Inner Mongolia (autonomous region, China) was applied to the model, and a 3D wind field has been successfully generated. The clear implementation of the model and the adequate validation by wind tunnel experiments laid a solid foundation for the prediction and assessment of wind erosion at regional scale.
In order to identify the areas in the Xilingele grassland which are sensitive to wind erosion, a computational fluid dynamics model (CFD-WEM) was used to simulate the wind fields over a region of 37 km(2) which contains different topography and land use types. Previous studies revealed the important influences of topography and land use on wind erosion in the Xilingele grassland. Topography influences wind fields at large scale, and land use influences wind fields near the ground. Two steps were designed to implement the CFD wind simulation, and they were respectively to simulate the influence of topography and surface roughness on the wind. Digital elevation model (DEM) and surface roughness length were the key inputs for the CFD simulation. The wind simulation by CFD-WEM was validated by a wind data set which was measured simultaneously at six positions in the field. Three scenarios with different wind velocities were designed based on observed dust storm events, and wind fields were simulated according to these scenarios to predict the sensitive areas to wind erosion. General assumptions that cropland is the most sensitive area to wind erosion and heavily and moderately grazed grasslands are both sensitive etc. can be refined by the modelling of CFD-WEM. Aided by the results of this study, the land use planning and protection measures against wind erosion can be more efficient. Based on the case study in the Xilingele grassland, a method of regional wind erosion assessment aided by CFD wind simulation is summarized. The essence of this method is a combination of CFD wind simulation and determination of threshold wind velocity for wind erosion. Because of the physically-based simulation and the flexibility of the method, it can be generalised to other regions.
The switching kinetics of thin thermo-responsive hydrogel films of poly(monomethoxy-diethyleneglycol-acrylate) (PMDEGA) are investigated. Homogeneous and smooth PMDEGA films with a thickness of 35.9 nm are prepared on silicon substrates by spin coating. As probed with white light interferometry, PMDEGA films with a thickness of 35.9 nm exhibit a phase transition temperature of the lower critical solution temperature (LCST) type of 40 degrees C. In situ neutron reflectivity is performed to investigate the thermo-responsive behavior of these PMDEGA hydrogel films in response to a sudden thermal stimulus in deuterated water vapor atmosphere. The collapse transition proceeds in a complex way which can be seen as three steps. The first step is the shrinkage of the initially swollen film by a release of water. In the second step the thickness remains constant with water molecules embedded in the film. In the third step, perhaps due to a conformational rearrangement of the collapsed PMDEGA chains, water is reabsorbed from the vapor atmosphere, thereby giving rise to a relaxation process. Both the shrinkage and relaxation processes can be described by a simple model of hydrogel deswelling.
A membrane of a dielectric elastomer coated with compliant electrodes may form wrinkles as the applied voltage is ramped up. We present a combination of experiment and theory to investigate the transition to wrinkles using a clamped membrane subject to a constant force and a voltage ramp. Two types of transitions are identified. In type-I transition, the voltage-stretch curve is N-shaped, and flat and wrinkled regions coexist in separate areas of the membrane. The type-I transition progresses by nucleation of small wrinkled regions, followed by the growth of the wrinkled regions at the expense of the flat regions, until the entire membrane is wrinkled. By contrast, in type-II transition, the voltage-stretch curve is monotonic, and the entire flat membrane becomes wrinkled with no nucleation barrier. The two types of transitions are analogous to the first and the second order phase transitions. While the type-I transition is accompanied by a jump in the vertical displacement, type-II transition is accompanied by a continuous change in the vertical displacement. Such transitions may enable applications in muscle-like actuation and energy harvesting, where large deformation and large energy of conversion are desired.
Multidirectional communicative interactions in social networks can have a profound effect on mate choice behavior. Male Atlantic molly Poecilia mexicana exhibit weaker mating preferences when an audience male is presented. This could be a male strategy to reduce sperm competition risk: interacting more equally with different females may be advantageous because rivals might copy mate choice decisions. In line with this hypothesis, a previous study found males to show a strong audience effect when being observed while exercising mate choice, but not when the rival was presented only before the choice tests. Audience effects on mate choice decisions have been quantified in poeciliid fishes using association preference designs, but it remains unknown if patterns found from measuring association times translate into actual mating behavior. Thus, we created five audience treatments simulating different forms of perceived sperm competition risk and determined focal males' mating preferences by scoring pre-mating (nipping) and mating behavior (gonopodial thrusting). Nipping did not reflect the pattern that was found when association preferences were measured, while a very similar pattern was uncovered in thrusting behavior. The strongest response was observed when the audience could eavesdrop on the focal male's behavior. A reduction in the strength of focal males' preferences was also seen after the rival male had an opportunity to mate with the focal male's preferred mate. In comparison, the reduction of mating preferences in response to an audience was greater when measuring association times than actual mating behavior. While measuring direct sexual interactions between the focal male and both stimulus females not only the male's motivational state is reflected but also females' behavior such as avoidance of male sexual harassment.
Die gewaltigen Strukturveränderungen im Bereich des Gesundheitswesens, die in den letzten Jahren bereits erfolgten und die, die noch bevorstehen, zwingen Unternehmen, mit geplanten und gesteuerten Veränderungsprozessen die Voraussetzungen für eine kontinuierliche Anpassung an die neuen Gegebenheiten zu schaffen und somit ihre Zukunftsfähigkeit sicherzustellen. Vor diesem Hintergrund wird gezeigt, wie das Excellence-Modell der EFQM als Instrument für Veränderungsprozesse eingesetzt werden kann und es geeignet ist, Veränderungsziele zu definieren und die Zielerreichung zu bewerten. Referenzobjekt der Fallstudienanalyse, die einen Zeitraum von 13 Jahren umfasst, ist der Medizinische Dienst der Krankenversicherung Rheinland-Pfalz. Neben der Analyse und Darstellung von theoretischen Grundlagen wird an einem Unternehmen des Gesundheitswesens beispielhaft gezeigt, wie die Umsetzung in der Praxis unter Einsatz des EFQM-Modells erfolgen kann. Da das EFQM-Modell mit seiner Systematik unternehmensunabhängig eingesetzt werden kann, sind Lern- und Übertragungsmöglichkeiten strukturiert möglich. Es wird der Nachweis erbracht, dass sich das EFQM-Modell im Rahmen eines Management- und Qualitätssteue-rungsmodells als Universalmethode nutzen lässt, sofern das Management über die Kompe-tenz branchenspezifischer Anpassung verfügt. Auf dem Weg zu organisatorischer Excel-lence wird gezielt an Planungs- und Prognosetechniken des strategischen Managements (SWOT, Szenario-Analyse, Portfolio-Analyse) angeknüpft und auf das VRIO-Paradigma des Resource-based View Bezug genommen. Das EFQM-Modell wird dem Stresstest des ressourcenstrategischen Ansatzes unterzogen, um so zu zeigen, dass es sich beim EFQM-Modell um ein einzigartiges, schwer imitierbares, kaum zu substituierendes, organisatorisch verankertes und kundennutzen-stiftendes Er-folgspotenzial handeln kann. Die Arbeit liefert Impulse und konkrete Anregungen, die zu einem hohen managementprakti-schen Erkenntniszuwachs für den erfolgreichen Umgang mit dem EFQM-Modell und dem Einsatz von Qualitätsmanagementsystemen führen können.
Aufbauend auf neuen Zugängen zu der Ende der 1970er Jahren entstandenen Regulationstheorie, die die Strukturen und Prozesse kapitalistischer Funktionsweise mit Elementen von Akkumulationsregimen, Regulation und Krise erklärt, werden von der Autorin sowohl der klassische Zugang als auch dessen Adaptionen auf verschiedene andere sozialwissenschaftliche Theorieansätze - wie z. B. dem Neo-Gramscianismus - kritisch hinterfragt. Aus dem Blickwinkel der Entwicklungsforschung und unter Hinzuziehung verschiedener Beispiele gegenwärtiger gesellschaftlicher Transformationsprozesse und emanzipatorischer Experimente in Lateinamerika wird aufgezeigt, dass die Regulationstheorie nach wie vor eine wertvolle Analysegrundlage für den gegenwärtigen Kapitalismus darstellt, jedoch einer Schwerpunktverlagerung bedarf.
Forests seem to represent low-erosion systems, according to most, but not all, studies of suspended-sediment yield. We surmised that this impression reflects an accidental bias in the selection of monitoring sites towards those with prevailing vertical hydrological flowpaths, rather than a tight causal link between vegetation cover and erosion alone. To evaluate this conjecture, we monitored, over a 2-year period, a 3.3 ha old-growth rainforest catchment prone to frequent and widespread overland flow. We sampled stream flow at two and overland flow at three sites in a nested arrangement on a within-event basis, and monitored the spatial and temporal frequency of overland flow. Suspended-sediment concentrations were modeled with Random Forest and Quantile Regression Forest to be able to estimate the annual yields for the 2 years, which amounted to 1 t ha(-1) and 2 t ha(-1) in a year with below-average and with average precipitation, respectively. These estimates place our monitoring site near the high end of reported suspended-sediment yields and lend credence to the notion that low yields reflect primarily the dominance of vertical flowpaths and not necessarily and exclusively the kind of vegetative cover. Undisturbed forest and surface erosion are certainly no contradiction in terms even in the absence of mass movements.
The adoption, in Kampala in June 2010, of amendments to the Rome Statute on the crime of aggression was hailed as a historic milestone in the development of the international Criminal Court (ICC). However, the manner in which these amendments are supposed to enter into force runs the risk of undermining the rules of the international law of treaties, as well as the legality and acceptability of the Kampala compromise itself The author examines the relevant amendment procedures provided for in the ICC Statute and the compatibility with them of the amendment procedure chosen in Kampala and ultimately warns of the legal consequences which may follow from the Review Conference's somewhat-Alexandrian solution.
Article 35
(2012)
State sucession in treaties
(2012)
Continuity of states
(2012)
Article 27
(2012)
Article 60
(2012)
Article 53
(2012)
Magnetic ionogels (MagIGs) were prepared from organosilane-coated iron oxide nanoparticles, N-isopropylacrylamide, and the ionic liquid trihexyl(tetradecyl)phosphonium dicyanamide. The ionogels prepared with the silane-modified nanoparticles are more homogeneous than ionogels prepared with unmodified magnetite particles. The silane-modified particles are immobilized in the ionogel and are resistant tonanoparticle leaching. The modified particles also render the ionogels mechanically more stable than the ionogels synthesized with unmodified nanoparticles. The ionogels respond to external permanent magnets and are therefore prototypes of a new soft magnetic actuator.
Determination of the source rocks for the diatexites from the Edough Massif, Annaba, NE Algeria
(2012)
The crystalline Edough Massif is located in the oriental part of the Algerian coastline. It consists of two tectonically superposed units of gneisses, augen-gneisses and migmatitic gneisses in the lower unit and micaschists in the upper unit. The crystalline rocks underwent a low to moderate degree of metamorphism; the gneisses suffered partial melting. They display migmatitic features such as nebulitic structures with contorted leucosome layers and K-feldspar porphyroblasts and thus can be classified as diatexites. The mineralogical composition of these rocks is very homogenous and consists of K-feldspar, micas and quartz. The feldspar-rich, arkosic nature of the outcrop implies a granitic source rock. High K2O/Na2O ratios and high A/CNK > 1.1 indicate an S-type granite source and a peraluminous composition of the protolith respectively. Chondrite normalized REE distribution patterns of the Edough diatexites show gently inclined patterns with a minor negative Eu anomaly (Eu/Eu* = 0.36-0.49), which points to a very slightly differentiated granitic source. The REE pattern and trace element data of the diatexites are similar to those of average Proterozoic upper continental crust, which suggests that they are derived mainly from upper continental crust and were deposited in continental margins.
The c-Fosc-Jun complex forms the activator protein 1 transcription factor, a therapeutic target in the treatment of cancer. Various synthetic peptides have been designed to try to selectively disrupt the interaction between c-Fos and c-Jun at its leucine zipper domain. To evaluate the binding affinity between these synthetic peptides and c-Fos, polarizable and nonpolarizable molecular dynamics (MD) simulations were conducted, and the resulting conformations were analyzed using the molecular mechanics generalized Born surface area (MM/GBSA) method to compute free energies of binding. In contrast to empirical and semiempirical approaches, the estimation of free energies of binding using a combination of MD simulations and the MM/GBSA approach takes into account dynamical properties such as conformational changes, as well as solvation effects and hydrophobic and hydrophilic interactions. The predicted binding affinities of the series of c-Jun-based peptides targeting the c-Fos peptide show good correlation with experimental melting temperatures. This provides the basis for the rational design of peptides based on internal, van der Waals, and electrostatic interactions.
Data limitations can lead to unrealistic fits of predictive species distribution models (SDMs) and spurious extrapolation to novel environments. Here, we want to draw attention to novel combinations of environmental predictors that are within the sampled range of individual predictors but are nevertheless outside the sample space. These tend to be overlooked when visualizing model behaviour. They may be a cause of differing model transferability and environmental change predictions between methods, a problem described in some studies but generally not well understood. We here use a simple simulated data example to illustrate the problem and provide new and complementary visualization techniques to explore model behaviour and predictions to novel environments. We then apply these in a more complex real-world example. Our results underscore the necessity of scrutinizing model fits, ecological theory and environmental novelty.
Empirical species distribution models (SDMs) constitute often the tool of choice for the assessment of rapid climate change effects on species vulnerability. Conclusions regarding extinction risks might be misleading, however, because SDMs do not explicitly incorporate dispersal or other demographic processes. Here, we supplement SDMs with a dynamic population model 1) to predict climate-induced range dynamics for black grouse in Switzerland, 2) to compare direct and indirect measures of extinction risks, and 3) to quantify uncertainty in predictions as well as the sources of that uncertainty. To this end, we linked models of habitat suitability to a spatially explicit, individual-based model. In an extensive sensitivity analysis, we quantified uncertainty in various model outputs introduced by different SDM algorithms, by different climate scenarios and by demographic model parameters. Potentially suitable habitats were predicted to shift uphill and eastwards. By the end of the 21st century, abrupt habitat losses were predicted in the western Prealps for some climate scenarios. In contrast, population size and occupied area were primarily controlled by currently negative population growth and gradually declined from the beginning of the century across all climate scenarios and SDM algorithms. However, predictions of population dynamic features were highly variable across simulations. Results indicate that inferring extinction probabilities simply from the quantity of suitable habitat may underestimate extinction risks because this may ignore important interactions between life history traits and available habitat. Also, in dynamic range predictions uncertainty in SDM algorithms and climate scenarios can become secondary to uncertainty in dynamic model components. Our study emphasises the need for principal evaluation tools like sensitivity analysis in order to assess uncertainty and robustness in dynamic range predictions. A more direct benefit of such robustness analysis is an improved mechanistic understanding of dynamic species responses to climate change.
We present a momentum transfer mechanism mediated by electromagnetic fields that originates in a system of two nearby molecules: one excited (donor D*) and the other in ground state (acceptor A). An intermolecular force related to fluorescence resonant energy or Forster transfer (FRET) arises in the unstable D* A molecular system, which differs from the equilibrium van der Waals interaction. Due to the its finite lifetime, a mechanical impulse is imparted to the relative motion in the system. We analyze the FRET impulse when the molecules are embedded in free space and find that its magnitude can be much greater than the single recoil photon momentum, getting comparable with the thermal momentum (Maxwell-Boltzmann distribution) at room temperature. In addition, we propose that this FRET impulse can be exploited in the generation of acoustic waves inside a film containing layers of donor and acceptor molecules, when a picosecond laser pulse excites the donors. This acoustic transient is distinguishable from that produced by thermal stress due to laser absorption, and may therefore play a role in photoacoustic spectroscopy. The effect can be seen as exciting a vibrating system like a string or organ pipe with light; it may be used as an opto-mechanical transducer.
Mit der Liberalisierung des Strommarkts, den unsicheren Aussichten in der Klimapolitik und stark schwankenden Preisen bei Brennstoffen, Emissionsrechten und Kraftwerkskomponenten hat bei Kraftwerksinvestitionen das Risikomanagement an Bedeutung gewonnen. Dies äußert sich im vermehrten Einsatz probabilistischer Verfahren. Insbesondere bei regulativen Risiken liefert der klassische, häufigkeitsbasierte Wahrscheinlichkeitsbegriff aber keine Handhabe zur Risikoquantifizierung. In dieser Arbeit werden Kraftwerksinvestitionen und -portfolien in Deutschland mit Methoden des Bayes'schen Risikomanagements bewertet. Die Bayes'sche Denkschule begreift Wahrscheinlichkeit als persönliches Maß für Unsicherheit. Wahrscheinlichkeiten können auch ohne statistische Datenanalyse allein mit Expertenbefragungen gewonnen werden. Das Zusammenwirken unsicherer Werttreiber wurde mit einem probabilistischen DCF-Modell (Discounted Cash Flow-Modell) spezifiziert und in ein Einflussdiagramm mit etwa 1200 Objekten umgesetzt. Da der Überwälzungsgrad von Brennstoff- und CO2-Kosten und damit die Höhe der von den Kraftwerken erwirtschafteten Deckungsbeiträge im Wettbewerb bestimmt werden, reicht eine einzelwirtschaftliche Betrachtung der Kraftwerke nicht aus. Strompreise und Auslastungen werden mit Heuristiken anhand der individuellen Position der Kraftwerke in der Merit Order bestimmt, d.h. anhand der nach kurzfristigen Grenzkosten gestaffelten Einsatzreihenfolge. Dazu wurden 113 thermische Großkraftwerke aus Deutschland in einer Merit Order vereinigt. Das Modell liefert Wahrscheinlichkeitsverteilungen für zentrale Größen wie Kapitalwerte von Bestandsportfolien sowie Stromgestehungskosten und Kapitalwerte von Einzelinvestitionen (Steinkohle- und Braunkohlekraftwerke mit und ohne CO2-Abscheidung sowie GuD-Kraftwerke). Der Wert der Bestandsportfolien von RWE, E.ON, EnBW und Vattenfall wird primär durch die Beiträge der Braunkohle- und Atomkraftwerke bestimmt. Erstaunlicherweise schlägt sich der Emissionshandel nicht in Verlusten nieder. Dies liegt einerseits an den Zusatzgewinnen der Atomkraftwerke, andererseits an den bis 2012 gratis zugeteilten Emissionsrechten, welche hohe Windfall-Profite generieren. Dadurch erweist sich der Emissionshandel in seiner konkreten Ausgestaltung insgesamt als gewinnbringendes Geschäft. Über die Restlaufzeit der Bestandskraftwerke resultiert ab 2008 aus der Einführung des Emissionshandels ein Barwertvorteil von insgesamt 8,6 Mrd. €. In ähnlicher Dimension liegen die Barwertvorteile aus der 2009 von der Bundesregierung in Aussicht gestellten Laufzeitverlängerung für Atomkraftwerke. Bei einer achtjährigen Laufzeitverlängerung ergäben sich je nach CO2-Preisniveau Barwertvorteile von 8 bis 15 Mrd. €. Mit höheren CO2-Preisen und Laufzeitverlängerungen von bis zu 28 Jahren würden 25 Mrd. € oder mehr zusätzlich anfallen. Langfristig erscheint fraglich, ob unter dem gegenwärtigen Marktdesign noch Anreize für Investitionen in fossile Kraftwerke gegeben sind. Zu Beginn der NAP 2-Periode noch rentable Investitionen in Braunkohle- und GuD-Kraftwerke werden mit der auslaufenden Gratiszuteilung von Emissionsrechten zunehmend unrentabler. Die Rentabilität wird durch Strommarkteffekte der erneuerbaren Energien und ausscheidender alter Gas- und Ölkraftwerke stetig weiter untergraben. Steinkohlekraftwerke erweisen sich selbst mit anfänglicher Gratiszuteilung als riskante Investition. Die festgestellten Anreizprobleme für Neuinvestitionen sollten jedoch nicht dem Emissionshandel zugeschrieben werden, sondern resultieren aus den an Grenzkosten orientierten Strompreisen. Das Anreizproblem ist allerdings bei moderaten CO2-Preisen am größten. Es gilt auch für Kraftwerke mit CO2-Abscheidung: Obwohl die erwarteten Vermeidungskosten für CCS-Kraftwerke gegenüber konventionellen Kohlekraftwerken im Jahr 2025 auf 25 €/t CO2 (Braunkohle) bzw. 38,5 €/t CO2 (Steinkohle) geschätzt werden, wird ihr Bau erst ab CO2-Preisen von 50 bzw. 77 €/t CO2 rentabel. Ob und welche Kraftwerksinvestitionen sich langfristig rechnen, wird letztlich aber politisch entschieden und ist selbst unter stark idealisierten Bedingungen kaum vorhersagbar.
Über die Autoren
(2012)
Autoritarismus Global
(2012)
Autoritarismus global: Entgegen vieler Erwartungen der Politikwissenschaft und des gehobenen Feuilletons aus den frühen 1990er Jahren scheint sich der autoritäre Regimetyp durchzusetzen. Antworten, die politische Regime auf alte und neue Herausforderungen geben, sind immer weniger demokratischer und immer mehr autoritärer Natur. Wir analysieren diesen WeltTrend: von Lateinamerika und Ostasien über Russland und den Nahen Osten bis in die Mitte Europas.
Wissensformen und Wissensnormen des ZusammenLebens : Literatur - Kultur - Geschichte - Medien
(2012)
Ernährung im 21. Jahrhundert
(2012)
The Eu Timescape
(2012)
Der Band „Perspektiven für morgen. Gedanken zur Zukunft von Politik, Wirtschaft und Gesellschaft“ eröffnet konkrete Perspektiven für eine nachhaltige und zukunftsfähige Entwicklung aus Sicht von Studierenden. In Form von Essays werden Lösungsansätze zu konkreten Fragen der Zukunftsfähigkeit und Nachhaltigkeit von Gesellschaft, Politik und Wirtschaft erarbeitet. Im ersten Teil - Zukunftsfähigkeit und Nachhaltigkeit - wird ein thematischer Einstieg in Grenzen und Chancen von Prognosen sowie eine Auseinandersetzung mit den Begriffen Nachhaltigkeit und Zukunftsfähigkeit gegeben. Das Kapitel Gesellschaft hat individuelle und gesellschaftliche Handlungspotentiale zum Gegenstand. Im Kapitel Politik werden Ansatzpunkte und Perspektiven nachhaltiger politischer Systeme, Entscheidungen und Strategien erarbeitet. Der Komplex Wirtschaft behandelt die globale Verteilung von Ressourcen sowie Fragestellungen der Arbeitsmarkt- und Finanzpolitik. Der Band ist im Rahmen eines Projektkurses an der Universität Potsdam im Wintersemester 2011/12 entstanden.
Klimapolitik International
(2012)
Der Klimawandel birgt globale Risiken. Dies ist weithin anerkannt. Umstritten ist die Frage, wie diesen Gefahren zu begegnen ist. 14 Jahre nach Kyoto ist klar: Klimapolitik ist Interessenpolitik. Das zeigte zuletzt die UN-Klimakonferenz 2011 in Durban mit ihren unverbindlichen Ergebnissen. In diesem Sammelband analysieren Experten Ursachen für das Scheitern der vergangenen Klima-Konferenzen und Konsequenzen für die künftige Klimapolitik. Insbesondere geht es um die Politik der Akteure China und Indien, um die Rolle der NGOs und die Klimafrage in der Entwicklungspolitik. Zugleich wird die deutsche Klimapolitik diskutiert und die Politik Brandenburgs von der verantwortlichen Ministerin vorgestellt.
In continuation of a successful series of events, the 4th Many-core Applications Research Community (MARC) symposium took place at the HPI in Potsdam on December 8th and 9th 2011. Over 60 researchers from different fields presented their work on many-core hardware architectures, their programming models, and the resulting research questions for the upcoming generation of heterogeneous parallel systems.
Weltunordnung 21
(2012)
Die internationale Ordnung ist im Umbruch. Aufstrebende Großmächte wie China, Brasilien und Russland fordern die US-amerikanische Dominanz des Westens heraus. Werden die neuen Gestaltungsansprüche zu einer gerechteren Weltpolitik führen – oder zu einer „neuen Weltunordnung“? WeltTrends setzt den Meinungsaustausch über Ordnungen und Unordnungen in der Welt des 21. Jahrhunderts in diesem Heft fort – fachkundig und vielseitig.
Über die Autoren
(2012)
Jahresbericht 2010/2011
(2012)
Inhalt: 1. Allgemeiner Überblick 2. Organisationsstruktur des MRZ 2.1 Angehörige des MRZ 2.2 Beirat 2.3 Förderverein 3. Aktivitäten im Berichtszeitraum 3.1 Wissenschaftliche Projekte und Veranstaltungen 3.2 Promotionen 3.3 Vorträge und Lehrveranstaltungen 3.4 Publikationen - Neuerscheinungen 2010/2011 4. Anhang - Satzung des MRZ
"Den Geist der Epoche bezeugen..." : 20 Jahre WeltTrends - Zeitschrift für internationale Politik
(2012)
Ernährung garantiert?
(2012)
Alle Menschen haben elementare Gemeinsamkeiten: Um zu überleben, müssen sie atmen, trinken – und essen. Doch ist Ernährung garantiert? Der Diskurs über globale Ernährungssicherung führte Jahrzehnte lang ein Schattendasein. Nun erfährt die Agrarwirtschaft eine Renaissance, doch ob dies den Hungernden zugutekommen wird, ist fraglich: Immer mehr Produkte sollen nicht den Energiebedarf der Menschen, sondern den der Maschinen decken. In unserem aktuellen Thema diskutieren Experten die Möglichkeiten und Risiken dieser veränderten Wertschätzung der Landwirtschaft.
Neue Weltordnung 2.0
(2012)
Wer ordnet die Welt im 21. Jahrhundert? Ist das Zeitalter der Hegemonie beendet? Welche Spieler werden das Great Game der nahen Zukunft bestimmen? Dies sind drängende Fragen der internationalen Politik – und wir liefern Antworten in unserem Themenschwerpunkt: sachlich und pointiert, faktenorientiert und kontrovers. „Neue Weltordnung“ war der Titel der ersten WeltTrends-Ausgabe 1993; „Neue Weltordnung 2.0“ ist der Titel der nunmehr 86. Ausgabe. Auch im 20. Jahrgang bleibt die Zeitschrift ein kritischer, kompetenter Begleiter weltpolitischer Ereignisse – mit Sicherheit!
rezensierte Werke: Chaim Vogt-Moykopf: Jüdisches Denken als universelles Konzept in der deutschsprachigen Literatur. - Frankfurt [u.a.] : Campus, 2009. - 280 S. ISBN 978-3-593-38910-3 Johannes Sabel: Die Geburt der Literatur aus der Aggada : Formationen eines deutsch-jüdischen Literaturparadigmas. - (Schriftenreihe wissenschaftlicher Abhandlungen des Leo Baeck Instituts ; 74). - Tübingen : Mohr Siebeck, 2010. - X, 296 S. ISBN 978-3-16-150209-5
Arabische Brüche
(2012)
Können Araber Demokratie? Im Jahr II des Arabischen Frühlings werden erste zarte Triebe der Hoffnungen, die in diese Richtung neigten, von Soldatenstiefeln und flüchtenden Demonstranten zertreten. Die versiegelte Zeit brach auf, doch was ist erreicht worden? In der neuen Ausgabe ziehen wir eine Bilanz, die ebenso sachlich wie zwiespältig ist. Sie zeigt Erfolge, ohne zu beschönigen. Probleme werden sichtbar gemacht, aber auch Wege zu ihrer Lösung. Auch Europa ist gefragt: Wir müssen zu einem neuen, partnerschaftlichen Verhältnis mit den sich wandelnden arabischen Nationen finden!
Für Stefan Zweig war Brasilien 1941 "ein Land der Zukunft". Die Realität sieht anders aus: Bis heute ist es ein Land der Gegensätze, geprägt vor allem durch jenen von Arm und Reich. Was Gini-Koeffizienten nüchtern in Zahlen ausdrücken, kann man in Metropolen mit hypermodernen Zentren und Favelas an Berghängen auf engstem Raum erleben. Vor allem die Verteilung von Land resultiert in Auseinandersetzungen. Experten analysieren im Thema die Lage eines Staates, der in seinen Widersprüchlichkeiten gefangen ist.
Inhalt: Editorial (Dr. Roswitha Lohwaßer) ; Auf Veränderungen reagieren. Herausforderungen an Beratungs- und Unterstützungssysteme im Kontext der Anforderungen an Schule
(Dr. Götz Bieber, Bernd Jankofsky) ; Lehrer qualifizieren, Kräfte bündeln. Überlegungen zur Enwicklung universitätsnaher Lehrerfortbildung in Niedersachsen (Dr. Jens Winkel, Ulrike Heinrichs) ; Nicht nur fachlich, auch didaktisch vorbereitet sein. Wann ist eine Fortbildung für Lehrkräfte eine gelungene Fortbildung (Elke Dengler) ; Der Lehrer - TÜV Qualitätscheck aus Schülersicht (Jorid Engler) ; Zusammenbringen, was zusammen gehört - universitäre Forschung und LehrerInnenfortbildung - (Dr. Charlotte Gemsa, Martina Rode) ; Wissensvermittlung spannend gestalten. Faszinierende numerische Experimente mit Polynomen - Fortbildung für Mathematiklehrer (Dr. Wolfgang Schöbel) ; Wow-Effekt, der Spaß an Mathe weckt. Erwartungen an eine Fortbildung für Mathematiklehrer (Jörg Schulz); Gemeinsames Lernen von Studierenden und Lehrenden. Was Potsdam von der Oldenburger Teamforschung lernen kann (Dr. Benjamin Apelojg) ; Design Thinking - Innovationsmethode für Projektarbeit. Ein Experiment im Helmholtz-Gymnasium (Andrea Scheer, Johannes Erdmann) ; Entwicklungen als Chance begreifen.
Lernkulturen und Portfolioarbeit in der Lehrerbildung (Dr. Mark-Oliver Carl) ; Rückblick auf die Tage der Lehrerbildung 2012
Am 1. und 2. Dezember 2011 fand am Hasso-Plattner-Institut für Softwaresystemtechnik GmbH in Potsdam der 4. Deutsche IPv6 Gipfel 2011 statt, dessen Dokumentation der vorliegende technische Report dient. Wie mit den vorhergegangenen nationalen IPv6-Gipfeln verfolgte der Deutsche IPv6-Rat auch mit dem 4. Gipfel, der unter dem Motto „Online on the Road - Der neue Standard IPv6 als Treiber der mobilen Kommunikation” stand, das Ziel, Einblicke in aktuelle Entwicklungen rund um den Einsatz von IPv6 diesmal mit einem Fokus auf die automobile Vernetzung zu geben. Gleichzeitig wurde betont, den effizienten und flächendeckenden Umstieg auf IPv6 voranzutreiben, Erfahrungen mit dem Umstieg auf und dem Einsatz von IPv6 auszutauschen, Wirtschaft und öffentliche Verwaltung zu ermutigen und motivieren, IPv6-basierte Lösungen einzusetzen und das öffentliche Problembewusstsein für die Notwendigkeit des Umstiegs auf IPv6 zu erhöhen. Ehrengast war in diesem Jahr die EU-Kommissarin für die Digitale Agenda, Neelie Kroes deren Vortrag von weiteren Beiträgen hochrangiger Vertretern aus Politik, Wissenschaft und Wirtschaft ergänzt wurde.
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