Structured latex particles with improved mechanical properties

Structured polymer latex particles are prepared by a swelling emulsion polymerization process, in which the initial particles are first swollen by ethylenically unsaturated monomers and the polymerization of the latter is then carried out. This special polymerization process leads to multi-phase particle morphology. Instead of a thermodynamically more favorable large-scale phase-separation, we obtain multiple, near-spherical domains dispersed within the particles. TEM analysis after selective staining reveals the size and distribution of the microdomains. Dynamic mechanical analysis of the polymer films confirms the absence of a distinct, large second phase and indicates that such microdomains interfere at the molecular level with the segmental mobility of the dispersing phase. We present examples of soft polymers as the continuous phase and hard polymers as the dispersed phase. The inclusion of hard microdomains into soft continuous phase increases dramatically both the films tensile strength and elongation, which means improved cohesive strength of the polymer material. The increase in tensile strength of the polymer film correlates directly with the hardness of the dispersed phase. Improvement in tensile strength and elongation is important in a number of industrial applications of polymers, such as flexible coatings, coalescent-free paints and pressure sensitive adhesives (PSAs). Examples are presented which demonstrate the potential applications of the swelling emulsion polymerization process.     

Architecture exploration and timing estimation during early design phases

Selecting the right computation hardware and configuration at the beginning of an industrial project is an important and highly risky task, which is usually done without much tool support, based on experience gathered from previous projects. We present TimingExplorer—a tool to assist in the exploration of alternative system configurations in early design phases. It is based on AbsInt’s WCET Analyser aiT and provides a selection of parametrisable cores that represent typical architectures of interest. Once some (representative) source code is available, TimingExplorer enables its users to take an informed decision which processor configurations are best suited for their needs. The usage of TimingExplorer facilitates the process of determining what processors to use and reduces the risk of timing problems becoming obvious only late in the development cycle and requiring a redesign of large parts of the system.     

Improved low temperature impact strength of polypropylene by modification with polyethylene

The deformation behaviour of polypropylene is briefly described. Using the SEM and TEM techniques the morphology and the dilatational processes during deformation have been studied in order to elucidate the improvement of impact strength of polypropylene at low temperatures by modification with polyethylene. The segregation of polyethylene in polypropylene appears to be a prerequisite in producing a structure capable of forming energy dissipating deformation zones (crazes).     

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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.     

Inspiration-triggered vasoconstrictive episodes in healthy subjects, in patients with diabetes mellitus and in patients with clinically manifest polyneuropathy of variable origin. A simple Doppler ultrasound test to assess the autonomic vascular functional unit of the upper extremity

BACKGROUND: A cost- and time efficient ultrasound-Doppler-test is introduced to evaluate the function of autonomic innervation of the upper limb. A voluntary inspiratory vasoconstrictor episode (VICE) after a provoked deep inspiration, transmitted via sympathetic nervous system, can be demonstrated at the radial artery using basic Doppler equipment. PATIENTS AND METHOD: VICEs were investigated in 30 healthy subjects (group A), in 20 patients with diabetes mellitus without clinical signs of polyneuropathy (group B) and in 20 patients with clinically manifest polyneuropathy (group C). RESULTS: In all healthy subjects a two minutes arterial occlusion led to a decrease of resistance index (RI) lower than 0.9 indicating sufficient hyperemia. RI during VICE increased to 1.0 in all healthy subjects. In 50% of the patients of group B as well as in 50% of the patients of group C the test revealed abnormal findings suggesting a disorder of the functional peripheral neurovascular unity.     

Briquetting of Coal Fines for Use in Smelting Reduction Processes

COREX®/FINEX® smelting reduction processes require lumpy coal for stable operation. The screened-off coal fines must be briquetted by means of binders to be utilizable for the COREX®/FINEX® processes. Optimal binder types, their amount, and briquetting conditions are identified by systematic experimental analyses. Experimental work is based on a critical review of literature to get knowledge about the theoretical background of hard coal briquetting, established hard coal briquetting technologies, and typical tests for metallurgical carbon carriers. Binder briquetting of hard coal is known to produce briquettes for heating. Compared to metallurgical use, briquettes quality and process behavior requirements are differing, but basic mechanisms like coal-binder-interaction are similar.     

Authentifizierung zwischen Datenschutz und Technikmisstrauen

Der elektronische Personalausweis geh?rt gemeinsam mit der De-Mail zu jenen Basiskomponenten, mit denen auch die neue Bundesregierung eine rechtssichere elektronische Kommunikation und rechtsverbindliche Authentifizierung der Bürgerinnen und Bürger gew?hrleisten m?chte. Der Aufbau einer solchen IT-Infrastruktur ist zu begrü?en. Allerdings zeichnen sich hier wie bei anderen technologischen Innovationen in der Hand des Staates auch Kritik und Protest ab, die ernst genommen werden sollten. Der Gesetzgeber sollte sich st?rker um die Rechtsfolgen unvermeidbarer IT-Unsicherheit bemühen.