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Gaussification and entanglement distillation of continuous-variable systems a unifying picture
(2012)
Distillation of entanglement using only Gaussian operations is an important primitive in quantum communication, quantum repeater architectures, and distributed quantum computing. Existing distillation protocols for continuous degrees of freedom are only known to converge to a Gaussian state when measurements yield precisely the vacuum outcome. In sharp contrast, non-Gaussian states can be deterministically converted into Gaussian states while preserving their second moments, albeit by usually reducing their degree of entanglement. In this work-based on a novel instance of a noncommutative central limit theorem-we introduce a picture general enough to encompass the known protocols leading to Gaussian states, and new classes of protocols including multipartite distillation. This gives the experimental option of balancing the merits of success probability against entanglement produced.
We generated medium-range forecasts of runoff for a 50 km(2) headwater catchment upstream of a reservoir using numerical weather predictions (NWPs) of the past as input to an operational hydrological model. NWP data originating from different sources were tested. For a period of 8.5 years, we computed daily forecasts with a lead time of +120 h based on an empirically downscaled version of the ECMWF's ensemble prediction system. For the last 3.5 years of the test period, we also tried the deterministic COSMO-EU forecast disseminated by the German Weather Service for lead times of up to +72 h. Common measures of skill indicate superiority of the ensemble runoff forecast over single-value forecasts for longer lead times. However, regardless of which NWP data were being used, the probability of event detection (POD) was found to be generally lower than 50%. In many cases, values in the range of 20-30% were obtained. At the same time, the false alarms ratio (FAR) was often found to be considerably high. The observed uncertainties in the hydrological forecasts were shown to originate from both the insufficient quality of precipitation forecasts as well as deficiencies in hydrological modeling and quantitative precipitation estimation. With respect to the anticipatory control of reservoirs in the studied catchment, the value of the tested runoff forecasts appears to be limited. This is due to the unfavorably low POD/FAR ratio in conjunction with a high cost-loss ratio. However, our results indicate that, in many cases, major runoff events related to snow melt can be successfully predicted as early as 4-5 days in advance.
Structure and the conformational properties of 1,3,3-trimethyl-1,3-azasilinane have been studied. According to gas electron diffraction (GED), the molecule exists in a slightly distorted chair conformation with the N-Me group in equatorial position. High-level quantum chemical calculations excellently, reproduce the experimental geometry. Employing variable temperature H-1 and C-13 NMR spectroscopy down to 103 K, the conformational equilibrium could be frozen and the barrier to ring inversion determined.
A facile one-pot synthesis for preparing thermosensitive, luminescent gold nanodots with diameters of 1-2 nm is presented. The influence of the alkyl chain length of the surface ligands (alkyl thiols) on the optical properties of the gold nanodots was investigated. The synthesized gold nanodots show strong thermosensitive photoluminescence. A photoluminescence quantum yield of 16.6% was observed at room temperature, which could be improved to a value of 28.6% when cooling the gold nanodot solutions to -7 degrees C. The synthesized thermosensitive, luminescent gold nanodots are interesting candidates for optoelectronic devices, medical imaging, sensing, or security labels.
Background: Different immunotherapy approaches for the treatment of cancer and autoimmune diseases are being developed and tested in clinical studies worldwide. Their resulting complex experimental data should be properly evaluated, therefore reliable normal healthy control baseline values are indispensable.
Methodology/Principal Findings: To assess intra- and inter-individual variability of various biomarkers, peripheral blood of 16 age and gender equilibrated healthy volunteers was sampled on 3 different days within a period of one month. Complex "crossomics'' analyses of plasma metabolite profiles, antibody concentrations and lymphocyte subset counts as well as whole genome expression profiling in CD4(+)T and NK cells were performed. Some of the observed age, gender and BMI dependences are in agreement with the existing knowledge, like negative correlation between sex hormone levels and age or BMI related increase in lipids and soluble sugars. Thus we can assume that the distribution of all 39.743 analysed markers is well representing the normal Caucasoid population. All lymphocyte subsets, 20% of metabolites and less than 10% of genes, were identified as highly variable in our dataset.
Conclusions/Significance: Our study shows that the intra- individual variability was at least two-fold lower compared to the inter-individual one at all investigated levels, showing the importance of personalised medicine approach from yet another perspective.
Preferential accumulation of mutant proteins in the nucleus has been suggested to be the molecular culprit that confers cellular toxicity in the neurodegenerative disorders caused by polyglutamine (polyQ) expansion. Here, we use dynamic imaging approaches, orthogonal cross-seeding, and composition analysis to examine the dynamics and structure of nuclear and cytoplasmic inclusions of atrophin-1, implicated in dentatorubropallidoluysian atrophy, a polyQ-based disease with complex clinical features. Our results reveal a large heterogeneity in the dynamics of the nuclear inclusions compared with the compact and immobile cytoplasmic aggregates. At least two types of inclusions of expanded atrophin-1 with different mobility of the molecular species and ability to exchange with the surrounding monomer pool coexist in the nucleus. Intriguingly, the enrichment of nuclear inclusions with slow dynamics parallels changes in the aggregate core architecture that are dominated by the polyQ stretch. We propose that the observed complexity in the dynamics of the nuclear inclusions provides a molecular explanation for the enhanced cellular toxicity of the nuclear aggregates in polyQ-based neurodegeneration.
Characterization of NE81, the first lamin-like nucleoskeleton protein in a unicellular organism
(2012)
Lamins build the nuclear lamina and are required for chromatin organization, gene expression, cell cycle progression, and mechanical stabilization. Despite these universal functions, lamins have so far been found only in metazoans. We have identified protein NE81 in Dictyostelium, which has properties that justify its denomination as a lamin-like protein in a lower eukaryote. This is based on its primary structure, subcellular localization, and regulation during mitosis, and its requirement of the C-terminal CaaX box as a posttranslational processing signal for proper localization. Our knockout and overexpression mutants revealed an important role for NE81 in nuclear integrity, chromatin organization, and mechanical stability of cells. All our results are in agreement with a role for NE81 in formation of a nuclear lamina. This function is corroborated by localization of Dictyostelium NE81 at the nuclear envelope in human cells. The discovery of a lamin-like protein in a unicellular organism is not only intriguing in light of evolution, it may also provide a simple experimental platform for studies of the molecular basis of laminopathies.
In our daily life, we often need to selectively remember information related to the same retrieval cue in a consecutive manner (e.g., ingredients from a recipe). To investigate such selection processes during cued long-term memory (LTM) retrieval, we used a paradigm in which the retrieval demands were systematically varied from trial to trial and analyzed, by means of behavior and slow cortical EEG potentials (SCPs), the retrieval processes in the current trial depending on those of the previous trial. We varied whether the retrieval cue, the type of to-be-retrieved association (feature), or retrieval load was repeated or changed from trial to trial. The behavioral data revealed a benefit of feature repetition, probably due to trial-by-trial feature priming. SCPs further showed an effect of cue change with a mid-frontal maximum, suggesting increased control demands when the cue was repeated, as well as a parietal effect of retrieval-load change, indicating increased activation of posterior neural resources when focusing on a single association after all learned associations had been activated previously, compared to staying with single associations across trials. These effects suggest the existence of two distinct types of dynamic (trial-by-trial) control processes during LTM retrieval: (1) medial frontal processes that monitor or regulate interference within a set of activated associations, and (2) posterior processes regulating attention to LTM representations. The present study demonstrates that processes mediating selective LTM retrieval can be successfully studied by manipulating the history of processing demands in trial sequences.
The SP-PLP-EPR technique is used to carry out a detailed investigation of the radical termination kinetics of 1H, 1H, 2H, 2H-tridecafluorooctyl methacrylate (TDFOMA) in bulk at relatively low conversion. Composite-model behavior for chain-length-dependent termination rate coefficients, kti,i, is observed. It is found that for TDFOMA, ic approximate to 60 independent of temperature, and as approximate to 0.65 and al approximate to 0.2 at 80 degrees C and above. However, at lower temperatures the situation is strikingly different, with the significantly higher average values of as = 0.89 +/- 0.15 and al = 0.32 +/- 0.10 being obtained at 50 degrees C and below. This makes TDFOMA the first monomer to be found that exhibits clearly different exponent values, as and al, at lower and higher temperature, and that has both a high as, like an acrylate, and a high ic, like a methacrylate.
The transition from cell proliferation to cell expansion is critical for determining leaf size. Andriankaja et al. (2012) demonstrate that in leaves of dicotyledonous plants, a basal proliferation zone is maintained for several days before abruptly disappearing, and that chloroplast differentiation is required to trigger the onset of cell expansion.