Segregation in eastern German cities: Gentrification, downgrading of large estates, and suburbanization

The following discussion deals with the changes in eastern German cities following the “Wende,” or turning point, in 1989. Residential segregation existed on a very limited scale in the GDR; but it can be assumed, given the rapid differentiation of social structure and housing conditions in eastern German cities, that it will become a dominant structural characteristic of cities there as well. The following discussion will present selected results of an empirical study of the city of Magdeburg. The study shows that the process of segregation, now taking place in the city as a whole after a somewhat hesitant beginning, can be broken down into various partial processes. And though the expected selective migration of the economically better off to prestigious residential areas from the end of the last century is only in its beginnings, problems are growing in some areas of the newer large estates that were built in the 70s and early 1980s. The downgrading of the newer large estates has also been the result of a massive trend toward suburbanization based on social and spatial selectivity since the Wende.     

Analysis of Inpainting via Clustered Sparsity and Microlocal Analysis

Recently, compressed sensing techniques in combination with both wavelet and directional representation systems have been very effectively applied to the problem of image inpainting. However, a mathematical analysis of these techniques which reveals the underlying geometrical content is missing. In this paper, we provide the first comprehensive analysis in the continuum domain utilizing the novel concept of clustered sparsity, which besides leading to asymptotic error bounds also makes the superior behavior of directional representation systems over wavelets precise. First, we propose an abstract model for problems of data recovery and derive error bounds for two different recovery schemes, namely ? ₁ minimization and thresholding. Second, we set up a particular microlocal model for an image governed by edges inspired by seismic data as well as a particular mask to model the missing data, namely a linear singularity masked by a horizontal strip. Applying the abstract estimate in the case of wavelets and of shearlets we prove that—provided the size of the missing part is asymptotic to the size of the analyzing functions—asymptotically precise inpainting can be obtained for this model. Finally, we show that shearlets can fill strictly larger gaps than wavelets in this model.     

The Role of the Plasma Membrane H+-ATPase in Plant-Microbe Interactions

T Plasma membrane (PM) H+-ATPases are the primary pumps responsible for the establishment of cellular membrane potential in plants. In addition to regulating basic aspects of plant cell function, these enzymes contribute to signaling events in response to diverse environmental stimuli. Here, we focus on the roles of the PM H+-ATPase during plantpathogen interactions. PM H+-ATPases are dynamically regulated during plant immune responses and recent quantitative proteomics studies suggest complex spatial and temporal modulation of PM H+-ATPase activity during early pathogen recognition events. Additional data indicate that PM H+-ATPases cooperate with the plant immune signaling protein RIN4 to regulate stomatal apertures during bacterial invasion of leaf tissue. Furthermore, pathogens have evolved mechanisms to manipulate PM H+-ATPase activity during infection. Thus, these ubiquitous plant enzymes contribute to plant immune responses and are targeted by pathogens to increase plant susceptibility.     

Uncertainty orientation and persuasion: Individual differences in the effects of personal relevance on social judgments.

In two studies we investigated the effects of personal relevance on attitude change as a function of one's uncertainty orientation. We predicted that, unlike uncertainty-oriented persons, high personal relevance would make certainty-oriented persons less careful or systematic in their processing of message arguments and more dependent on heuristics, or persuasion cues, than would low personal relevance. Results from both studies, within and across 2-week time periods, supported predictions. In Study 1, high personal relevance led to higher persuasiveness of two-sided communications and lower persuasiveness of one-sided communications than low personal relevance for uncertainty-oriented persons, but the reverse occurred for certainty-oriented persons. In Study 2, high personal relevance led to higher persuasive impact of strong arguments and lower impact for source expertise than did low personal relevance for uncertainty-oriented persons, but, again, the reverse occurred for certainty-oriented persons. We discuss implications for current theories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Amino acid clusters formed by sonic spray ionization

A novel ion source based on the principle of sonic spray ionization has been built and used to optimize mass spectrometric conditions for generating amino acid clusters. The ion source employs a simple pneumatic spray operated at extremely high nebulizing gas flow rates. Several factors that affect the performance of the cluster source are identified, and information from these observations provides insights into the mechanisms of gas phase ion formation. Serine is used as a model system in optimizing instrumental and sample parameters to maximize cluster ion formation. The sonic spray results for this oligomer compare favorably with electrospray data, showing an order of magnitude better signal intensity and excellent signal-to-noise ratios. The performance of the system for the protonated serine octamer includes a limit of detection of 10 nM and a linear dynamic range of 4 orders of magnitude. Ion formation was observed to go into saturation above 1 mM. This result and data on pH, electrolyte concentration, and solvent composition are interpreted as supporting a charge residue model of sonic spray ionization. Other amino acids can be substituted for serine in the octamer, with a strong chiral preference in favor of homochiral cluster formation in the cases of threonine and cysteine. These amino acids show a preference for substitution of more than two serine molecules. Phenylalanine, asparagine, tryptophan, and tyrosine also substitute into the serine octamer; however, the process yields only two incorporations and only small chiral effects.     

Structural Characterization of Daunomycin-Peptide Conjugates by Various Tandem Mass Spectrometric Techniques

The use of peptide-drug conjugates has generated wide interest as targeted antitumor therapeutics. The anthracycline antibiotic, daunomycin, is a widely used anticancer agent and it is often conjugated to different tumor homing peptides. However, comprehensive analytical characterization of these conjugates via tandem mass spectrometry (MS/MS) is challenging due to the lability of the O-glycosidic bond and the appearance of MS/MS fragment ions with little structural information. Therefore, we aimed to investigate the optimal fragmentation conditions that suppress the prevalent dissociation of the anthracycline drug and provide good sequence coverage. In this study, we comprehensively compared the performance of common fragmentation techniques, such as higher energy collisional dissociation (HCD), electron transfer dissociation (ETD), electron-transfer higher energy collisional dissociation (EThcD) and matrix-assisted laser desorption/ionization–tandem time-of-flight (MALDI-TOF/TOF) activation methods for the structural identification of synthetic daunomycin-peptide conjugates by high-resolution tandem mass spectrometry. Our results showed that peptide backbone fragmentation was inhibited by applying electron-based dissociation methods to conjugates, most possibly due to the “electron predator” effect of the daunomycin. We found that efficient HCD fragmentation was largely influenced by several factors, such as amino acid sequences, charge states and HCD energy. High energy HCD and MALDI-TOF/TOF combined with collision induced dissociation (CID) mode are the methods of choice to unambiguously assign the sequence, localize different conjugation sites and differentiate conjugate isomers.     

Effects of Root Herbivory by Nematodes on the Performance and Preference of a Leaf-Infesting Generalist Aphid Depend on Nitrate Fertilization

The performance and behavior of herbivores is strongly affected by the quality of their host plants, which is determined by various environmental conditions. We investigated the performance and preference of the polyphagous shoot-infesting aphid Myzus persicae on the host-plant Arabidopsis thaliana in a two-factorial design in which nitrate fertilization was varied by 33 %, and the root-infesting cyst-nematode Heterodera schachtii was present or absent. Aphid performance was influenced by these abiotic and biotic factors in an interactive way. Nematode presence decreased aphid performance when nitrate levels were low, whereas nematode infestation did not influence aphid performance under higher nitrate fertilization. Aphids followed the “mother knows best” principle when given a choice, settling preferentially on those plants on which they performed best. Hence, they preferred nematode-free over nematode-infested plants in the low fertilization treatment but host choice was not affected by nematodes under higher nitrate fertilization. The amino acid composition of the phloem exudates was significantly influenced by fertilization but also by the interaction of the two treatments. Various glucosinolates in the leaves, which provide an estimate of phloem glucosinolates, were not affected by the individual treatments but by the combination of fertilization and herbivory. These changes in primary and secondary metabolites may be decisive for the herbivore responses. Our data demonstrate that abiotic and biotic factors can interactively affect herbivores, adding a layer of complexity to plant-mediated herbivore interactions.     

Concentration and coating time effects of N-acyl sarcosine derivatives for corrosion protection of low-carbon steel CR4 in salt water – defining the window of application

ABSTRACT

Potential natural and environment-friendly substances are often used as substitutes for inhibitors to protect steel against corrosion in a sustainable way. Here, three biodegradable N-acyl sarcosine derivatives are evaluated for corrosion protection by polarisation, weight loss, electrochemical impedance, optical and scanning electron microscopy (SEM) spectroscopy including energy dispersive spectroscopy (EDS) to find the best possible application interval of concentration and dip-coating time. The substances present vary in their carbon chain length on the sarcosine-amino acid and are tested in 0.1?M NaCl as protective barrier for low-carbon steel CR4. Corrosion protection improved with increasing sarcosine concentration in the dip-coating stock solutions (25, 50, 75, and 100?mmol/L). Best efficiencies were found in polarisation for the highest studied concentrations of Oleoylsarcosine (O) with 97% followed by Myristoylsarcosine (M) with 82%. The lowest overall performance showed the shorter Lauroylsarcosine (L) with 51%. The best immersion time for dip-coating on CR4 for present compounds turned out to be 10?min. Surface analysis results with SEM and EDS revealed a significant higher C content caused by increased film-forming adsorption of sarcosines on the metal surface.