Two 2D postprocessing tools and their applications to the improvement of 3D pictures

When displaying abstract objects, as in the case of scientific visualization, it is manadatory to give the user a maximum of cues to help him understand the displayed structures. In this short note, we describe two general, simple 2D postprocessing tools and their applications for the improvement of 3D perception by means of simulation of realistic 3D effects.     

Share with strangers: Privacy bubbles as user-centered privacy control for mobile content sharing applications

A continually increasing number of pictures and videos is shared in online social networks. Current sharing platforms, however, only offer limited options to define who has access to the content. Users may either share it with individuals or groups from their social graph, or make it available to the general public. Sharing content with users to which no social ties exist, even if they were physically close to the places where content was created and witnessed the same event, is however not supported by most existing platforms. We thus propose a novel approach to share content with such users based on so-called privacy bubbles. Privacy bubbles metaphorically represent the private sphere of the users and automatically confine the access to the content generated by the bubble creator to people within the bubble. Bubbles extend in both time and space, centered around the collection time and place, and their size can be adapted to the user's preferences. We confirm the user acceptance of our concept through a questionnaire-based study with 175 participants, and a prototype implementation shows the technical feasibility of our scheme.     

Preparation of metal‐containing protein fibers and their antimicrobial properties

Bombyx mori silk, Antheraea pernyi silk, and wool fibers were chemically modified by treatment with tannic acid (TA) or by acylation with ethylenediaminetetraacetic (EDTA) dianhydride. Kinetics of TA loading or acylation with EDTA‐dianhydride varied from fiber to fiber. B. mori silk and wool displayed the highest weight gains with TA and EDTA‐dianhydride, respectively. The uptake of different metal ions (Ag⁺, Cu²⁺, Co²⁺) by protein fibers, either untreated or chemically modified, was studied as a function of weight gain and pH of the aqueous metal solution. Below pH 7, absorption of metal ions by untreated and TA‐treated fibers was negligible. Acylation with EDTA‐dianhydride enabled protein fibers to absorb and bind significant amounts of metal ions in the acidic and neutral pH range. The levels of metal desorption at acidic pH depended on the fiber‐metal combination. Untreated protein fibers usually displayed the lowest stability of the metal complex. Metal complexes with protein fibers exhibited prominent antimicrobial activity against the plant pathogen Cornebacterium. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 638–644, 2003     

Super‐Resolution Microscopy Unveils Dynamic Heterogeneities in Nanoparticle Protein Corona

The adsorption of serum proteins, leading to the formation of a biomolecular corona, is a key determinant of the biological identity of nanoparticles in vivo. Therefore, gaining knowledge on the formation, composition, and temporal evolution of the corona is of utmost importance for the development of nanoparticle‐based therapies. Here, it is shown that the use of super‐resolution optical microscopy enables the imaging of the protein corona on mesoporous silica nanoparticles with single protein sensitivity. Particle‐by‐particle quantification reveals a significant heterogeneity in protein absorption under native conditions. Moreover, the diversity of the corona evolves over time depending on the surface chemistry and degradability of the particles. This paper investigates the consequences of protein adsorption for specific cell targeting by antibody‐functionalized nanoparticles providing a detailed understanding of corona‐activity relations. The methodology is widely applicable to a variety of nanostructures and complements the existing ensemble approaches for protein corona study.     

Study on microstructural, chemical and electrical properties of tantalum nitride thin films deposited by reactive direct current magnetron sputtering

The properties of tantalum nitride (TaN_x) thin films on silicon and low temperature co-fired ceramics based substrates were investigated with respect to their potential use for sensor elements operated under harsh environmental conditions. For deposition reactive direct current magnetron sputtering was applied at constant back pressure (=0.9 Pa) and plasma power (=1,000 W). In all experiments, the substrates were nominally unheated. The films were investigated electrically by four point probing. For morphological and chemical analyses, a large variety of techniques such as focussed ion beam, scanning electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy and glow discharge optical emission spectroscopy were used. Only by combining all these techniques for analysing TaN_x films synthesised with varying nitrogen content in the deposition chamber can a proper evaluation of the microstructure and the chemical composition be done. Both the microstructure and the chemical composition are influenced strongly with a resulting effect on the electrical film properties.     

Efficient algorithms for descendant-only tree pattern queries

Tree pattern matching is a fundamental problem that has a wide range of applications in Web data management, XML processing, and selective data dissemination. In this paper we develop efficient algorithms for the tree homeomorphism problem, i.e., the problem of matching a tree pattern with exclusively transitive (descendant) edges. We first prove that deciding whether there is a tree homeomorphism is LOGSPACE-complete, improving on the current LOGCFL upper bound. Furthermore, we develop a practical algorithm for the tree homeomorphism decision problem that is both space- and time-efficient. The algorithm is in LOGDCFL and space consumption is strongly bounded, while the running time is linear in the size of the data tree. This algorithm immediately generalizes to the problem of matching the tree pattern against all subtrees of the data tree, preserving the mentioned efficiency properties.     

The Potential of Confocal Imaging for Measuring Physiological Changes in Brewer's Yeast

This study focused on the implementation of fluorescence optical methods and laser scanning confocal microscopy for monitoring brewing yeast performance. Physiological parameters and cell compounds in yeast cells (glycogen, neutral lipids, trehalose, bud scars, DNA and intracellular proteinases) have been successfully visualised with the aid of highly specific fluorochromes. The expression and sub cellular localisation of proteinase A during fermentation has been studied employing a Saccharomyces cerevisiae green fluorescent protein clone. This novel approach to monitoring brewing yeast performance provides new insights into physiological events that occur during wort fermentation.     

Surface forces, surface chemistry and tribology

Scanning probe methods have been applied to the investigation of tribological phenomena on the nanometre and nanonewton scale. The systems studied have included parallel investigation of identical tribosystems on the macro and nano scales, where the inherent differences in the AFM/LFM and flat-on-disk experiments have been compared; oxide-covered surfaces in contact under electrolytes, where the adhesion hysteresis and frictional behaviour was shown to be strongly dependent on the solution pH; and polymer surfaces, where advantage can be taken of variations in the interactions between the scanning tip and different polymers, to perform chemically sensitive, high-resolution surface imaging of polymer blends.     

Fetal Zone Steroids and Estrogen Show Sex Specific Effects on Oligodendrocyte Precursor Cells in Response to Oxidative Damage

Oxygen causes white matter damage in preterm infants and male sex is a major risk factor for poor neurological outcome, which speculates the role of steroid hormones in sex-based differences. Preterm birth is accompanied by a drop in 17β-estradiol (E2) and progesterone along with increased levels of fetal zone steroids (FZS). We performed a sex-based analysis on the FZS concentration differences in urine samples collected from preterm and term infants. We show that, in preterm urine samples, the total concentration of FZS, and in particular the 16α-OH-DHEA concentration, is significantly higher in ill female infants as compared to males. Since we previously identified Nup133 as a novel target protein affected by hyperoxia, here we studied the effect of FZS, allopregnanolone (Allo) and E2 on differentiation and Nup133 signaling using mouse-derived primary oligodendrocyte progenitor cells (OPCs). We show that the steroids could reverse the effect of hyperoxia-mediated downregulation of Nup133 in cultured male OPCs. The addition of FZS and E2 protected cells from oxidative stress. However, E2, in presence of 16α-OH-DHEA, showed a negative effect on male cells. These results assert the importance of sex-based differences and their potential implications in preterm stress response.     

Count data regression charts for the monitoring of surveillance time series

Control charts based on the Poisson and negative binomial distribution for monitoring time series of counts typically arising in the surveillance of infectious diseases are presented. The in-control mean is assumed to be time-varying and linear on the log-scale with intercept and seasonal components. If a shift in the intercept occurs the system goes out-of-control. Using the generalized likelihood ratio (GLR) statistic a monitoring scheme is formulated to detect on-line whether a shift in the intercept occurred. In the case of Poisson the necessary quantities of the GLR detector can be efficiently computed by recursive formulas. Extensions to more general alternatives e.g. containing an auto-regressive epidemic component are discussed. Using Monte Carlo simulations run-length properties of the proposed schemes are investigated and the Poisson scheme is compared to existing methods. The practicability of the charts is demonstrated by applying them to the observed number of salmonella hadar cases in Germany 2001-2006.