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In recent communications from these laboratories, we observed that amine-rich thin organic layers are very efficient surfaces for the adhesion of mammalian cells. We prepare such deposits by plasma polymerization at low pressure, atmospheric pressure, or by vacuum-ultraviolet photo-polymerization. More recently, we have also investigated a commercially available material, Parylene diX AM. In this article we first briefly introduce literature relating to electrostatic interactions between cells, proteins, and charged surfaces. We then present certain selected cell-response results that pertain to applications in orthopedic and cardiovascular medicine: we discuss the influence of surface properties on the observed behaviors of two particular cell lines, human U937 monocytes, and Chinese hamster ovary cells. Particular emphasis is placed on possible electrostatic attractive forces due to positively charged R-NH3+ groups and negatively charged proteins and cells, respectively. Experiments carried out with electrets, polymers with high positive or negative surface potentials are added for comparison.
Determining covalent and charge-transfer contributions to bonding in solution has remained an experimental challenge. Here, the quenching of fluorescence decay channels as expressed in dips in the L-edge X-ray spectra of solvated 3d transition-metal ions and complexes was reported as a probe. With a full set of experimental and theoretical ab initio L-edge X-ray spectra of aqueous Cr3+, including resonant inelastic X-ray scattering, we address covalency and charge transfer for this prototypical transition-metal ion in solution. We dissect local atomic effects from intermolecular interactions and quantify X-ray optical effects. We find no evidence for the asserted ultrafast charge transfer to the solvent and show that the dips are readily explained by X-ray optical effects and local atomic state dependence of the fluorescence yield. Instead, we find, besides ionic interactions, a covalent contribution to the bonding in the aqueous complex of ligand-to-metal charge-transfer character.
Context. The variation of the dimensionless fundamental physical constant mu = m(p)/m(e) - the proton to electron mass ratio - can be constrained via observation of Lyman and Werner lines of molecular hydrogen in the spectra of damped Lyman alpha systems (DLAs) in the line of sight to distant QSOs.
Aims. Our intention is to maximize the possible precision of quasar absorption spectroscopy with regard to the investigation of the variation of the proton-to-electron mass-ratio mu. The demand for precision requires an understanding of the errors involved and effective techniques to handle present systematic errors.
Methods. An analysis based on UVES high resolution data sets of QSO 0347-383 and its DLA is put forward and new approaches to some of the steps involved in the data analysis are introduced. We apply corrections for the observed offsets between discrete spectra and for the first time we find indications for inter-order distortions.
Results. Drawing on VLT-UVES observations of QSO 0347-383 in 2009 our analysis yields Delta mu/mu = (4.3 +/- 7.2) x 10(-6) at z(abs) = 3.025.
Conclusions. Current analyzes tend to underestimate the impact of systematic errors. Based on the scatter of the measured redshifts and the corresponding low significance of the redshift-sensitivity correlation we estimate the limit of accuracy of line position measurements to similar to 220 m s (1), consisting of roughly 150 m s (1) due to the uncertainty of the absorption line fit and about 150 m s (1) allocated to systematics related to instrumentation and calibration.
Putting the plan into practice implementation of proposals for measures of local landscape plans
(2012)
The knowledge of the effectiveness of local landscape planning in Germany is in the main limited to particular cases and derives mostly from qualitative single case studies. This applies especially to the implementation of measures defined by landscape plans. To fill that gap, the paper focuses on the implementation of those measures. Furthermore, it discusses the factors and framework conditions which are crucial for this implementation. The potential factors and conditions of influence were derived from theory and compiled in 20 investigation hypotheses. In order to gain information on the execution of the measures, 28 randomly selected plans were first analysed, then interviews were carried out with administration representatives. It can be stated that landscape planning has positively influenced the development of nature and landscape in the investigated municipalities. A considerable number of measures had been implemented, although landscape planning as a supply-side instrument proposes generally a very large number of measures. Factors with a positive effect on the implementation of landscape planning measures are pointed out.
Silvicultural practices lead to changes in forest composition and structure and may impact species diversity from the overall regional species pool to stand-level species occurrence. We explored to what extent fine-scale occupancy patterns in differently managed forest stands are driven by environment and ecological traits in three regions in Germany using a multi-species hierarchical model. We tested for the possible impact of environmental variables and ecological traits on occupancy dynamics in a joint modelling exercise while taking possible variation in coefficient estimates over years and plots into account. Bird species richness differed across regions and years, and trends in species richness across years were different in the three regions. On the species level, forest management affected occupancy of species in all regions, but only 35% of the total assemblage-level variation in occurrence probability was explained by either forest type and successional stage and <?1% by forest edge. On the assemblage level, bird occurrence decreased with body mass in all regions. Species with smaller breeding ranges had lower occurrence probabilities in one region, while later spring arrival decreased occurrence probabilities in the two other regions. Spatial variation in the effect size of trait covariates such as species phylogeny and breeding strata showed that variation in patch occupancy due to fine-scale differences in forest management is, to some extent, predictable from ecological traits. Our results show that environmental factors and ecological traits jointly predict variation in bird occupancy patterns and their response to forest management. Observations at the fine scale of forest stands, at which conservation efforts can be arranged along with forest management practices in heterogeneous environments, have been shown to provide meaningful insights despite the difficulties involved in monitoring mobile organisms such as birds at the plot level.
Previous studies have revealed that infants aged 6-10 months are able to use the acoustic correlates of major prosodic boundaries, that is, pitch change, preboundary lengthening, and pause, for the segmentation of the continuous speech signal. Moreover, investigations with American-English- and Dutch-learning infants suggest that processing prosodic boundary markings involves a weighting of these cues. This weighting seems to develop with increasing exposure to the native language and to underlie crosslinguistic variation. In the following, we report the results of four experiments using the headturn preference procedure to explore the perception of prosodic boundary cues in German infants. We presented 8-month-old infants with a sequence of names in two different prosodic groupings, with or without boundary markers. Infants discriminated both sequences when the boundary was marked by all three cues (Experiment 1) and when it was marked by a pitch change and preboundary lengthening in combination (Experiment 2). The presence of a pitch change (Experiment 3) or preboundary lengthening (Experiment 4) as single cues did not lead to a successful discrimination. Our results indicate that pause is not a necessary cue for German infants. Pitch change and preboundary lengthening in combination, but not as single cues, are sufficient. Hence, by 8 months infants only rely on a convergence of boundary markers. Comparisons with adults' performance on the same stimulus materials suggest that the pattern observed with the 8-month-olds is already consistent with that of adults. We discuss our findings with respect to crosslinguistic variation and the development of a language-specific prosodic cue weighting.
Cyanobacteria or blue-green algae from various environments have been recognized as sources of a variety of bioactive metabolites. Strategies of strain isolation from aquatic habitats, and cultivation and harvesting for metabolite production are described. Strategies for screening of compounds are discussed, including their direct MALDI-TOF mass spectrometric detection in whole cells. Genetic approaches including genomic mining, mutagenesis including transcriptional activation, heterologous expression, and in vitro. reconstitution of pathways are presented.
Human rights can be understood as a multi-faceted concept which needs a strong legal basis, namely, a set of legal guarantees in human rights treaties and an increasing number of monitoring mechanisms. Following the Universal Declaration of Human Rights (UDHR) of December 10, 1948, various multi-lateral treaties for the protection of human rights have been negotiated and entered into force. They are not restricted to civil and political rights and take a much broader approach. All have monitoring mechanisms acting on a legal basis. The important European system with its strong, judicial monitoring mechanism is providing an effective human rights protection focused on civil and political rights. In the Görgülü case (2004), the German Federal Constitutional Court underlined the importance of the European Court’s judgments and of the ECHR as a legally binding instrument for the protection of human rights.
Random copolymers of 4-vinylbenzyl tri(oxyethylene) and tetra(oxyethylene) ethers, as well as alternating copolymers of 4-vinylbenzyl methoxytetra(oxyethylene) ether and a series of N-substituted maleimides, were synthesised by conventional free radical polymerisation, reversible addition fragmentation chain transfer (RAFT) and atom transfer radical polymerisation (ATRP). Their thermosensitive behaviour in aqueous solution was studied by turbidimetry and dynamic light scattering. Depending on the copolymer composition, a LCST type phase transition was observed in water. The transition temperature of the obtained random as well as alternating copolymers could be varied within a broad temperature window. In the case of the random copolymers, transition temperatures could be easily fine-tuned, as they showed a linear dependence on the copolymer composition, and were additionally modified by the nature of the polymer end-groups. Alternating copolymers were extremely versatile for implementing a broad range of variations of the phase transition temperatures. Further, while alternating copolymers derived from 4-vinylbenzyl methoxytetra(oxyethylene) ether and maleimides with small hydrophobic side chains underwent macroscopic phase separation when dissolved in water and heated above their cloud point, the incorporation of maleimides bearing larger hydrophobic substituents resulted in the formation of mesoglobules above the phase transition temperature, with hydrodynamic diameters of less than 100 nm.