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Block copolymers were prepared with two anionic polyelectrolyte blocks: sodium polyacrylate (PA) and sodium polystyrene sulfonate (PSS), in order to investigate their phase behavior in aqueous solution in the presence of Ca2+ cations. Depending on the concentration of polymer and Ca2+ and on the ratio of the block lengths in the copolymer, spherical micelles were observed. Micelle formation arises from the specific interaction of Ca2+ with the PA block only. An extensive small-angle scattering study was performed in order to unravel the structure and dimensions of the block copolymer micelles. Deuteration of the PA block enabled us to perform contrast variation experiments using small-angle neutron scattering at variable ratios of light and heavy water which were combined with information from small-angle X-ray scattering and dynamic light scattering.

Dodecyl amine edge functionalized few-layer graphene oxide quantum dots were synthesized in good yields. The covalent functionalization was demonstrated with NMR and AFM-IR. The resulting structure and particle size was measured with AFM and HRTEM. The thermal stability of the compound was investigated and showed a stability of up to 220 °C. The modified graphene oxide quantum dots showed excellent solubility in various organic solvents, including ethers, methanol, toluene, n-hexane, heptane, xylene, dichloromethane and toluene. The stability of a resulting toluene solution was also proven by static light scattering measurements over several days. The excellent solubility gives the possibility of an efficient and fast spray application of the functionalized graphene oxide quantum dots to steel surfaces. Hence, the macroscopic friction behavior was investigated with a Thwing-Albert FP-2250 friction tester. A thin film of the dodecyl amine functionalized graphene oxide quantum dots on steel lowered the friction coefficient from 0.17 to 0.11 and revealed a significant corrosion inhibition effect.

No actual data are available on the epidemiology and morbidity of community acquired pneumonia (CAP) in youths and children in Vienna, Austria. The objective was to determine the epidemiology of CAP and morbidity of children hospitalized due to CAP in a tertiary care facility. During three winter seasons youths and children hospitalized due to CAP were enrolled. Testing for viral and bacterial pathogens of pneumonia was performed in a routine clinical setting. Blood cultures were performed; respiratory viruses, Mycoplasma pneumoniae and Chlamydia pneumoniae were searched for by an established Real Time polymerase chain reaction (PCR) panel. Clinical signs and indices of inflammation were documented. Out of 279 children and youths with CAP a causative agent could be detected in 190 (68 %). Viruses and bacteria were diagnosed in 107 (57 %) and 58 patients (30 %), respectively. Co-infection was found in 20 patients (10 %), Mycoplasma pneumoniae or Clamydia pneumoniae in 16 cases (8 %). In seven patients blood cultures were positive. C-reactive protein (CRP) was significantly higher in children with positive Streptococcus pneumoniae antigen (SPAG) than with viral infection and/or co-infection. Clinical parameters showed no statistically significant differences. C. pneumoniae and M. pneumoniae were only diagnosed in children and youths with 5 years and older. Testing for pathogens in CAP in clinical routine achieves a high recovery rate. Blood cultures are rarely helpful, but the molecular testing for viruses seemed to be helpful to establish the diagnosis.

We performed a replication study in 883 Austrian multiple sclerosis (MS) patients and 972 control individuals for 25 previously risk-associated loci (39 SNPs). Two loci, rs1109670 (DDEF2/MBOAT2, p

The role of the CLSTN2 (rs6439886) and KIBRA (rs17070145) SNPs in cognitive impairment was analysed in a 75-76 years old group. Various memory assessment tests were carried out on individuals at baseline and during follow-up investigations, and biallelic genotyping was performed. No influence of the allele status of either SNPs was observed on any memory test. No increased risk of any type of late development, and cognitive impairment was associated with rs6439886 or rs17070145.

BACKGROUND: Retinol-binding protein (RBP) 4, a human adipokine that specifically binds to retinol, has been reported to provide a link between obesity and insulin resistance. Plasma RBP4 concentration may be under the influence of age and obesity, but only a few studies has investigated this link in elderly individuals. Consequently, we tested the correlation between RBP4 concentrations and type 2 diabetes/metabolic syndrome (MetS) components in a large population based cohort study (VITA) of elderly [1, 2]. Using a single birth cohort, this investigation could exclude the influence of age. METHODS: We evaluated the correlation of RBP4 with type 2 diabetes and MetS components including Body Mass Index (BMI), blood pressure, lipid parameters, fasting glucose insulin, homeostasis model assessment insulin resistance (HOMA-IR), and smoking in exclusively 75–76 year old participants (N = 232). RESULTS: In the present study, RBP4 concentrations were associated with type 2 diabetes and metabolic syndrome (MetS) components. Of all the individual components of metabolic syndrome that were associated with RBP4 concentrations, the correlations of RBP4 with serum triglycerides and a negative correlation with HDL were the strongest ones observed in our study cohort (p

Globally, cardiovascular diseases (CVDs) are the number one cause of all mortalities. Of these deaths, 7.6 million are due to heart attacks, and 5.7 millions are due to stroke. The Vienna Transdanube Aging Study (VITA), a population-based cohort study, enabled us to evaluate associations between the known major risk factors for cerebrovascular and CVDs and their appearance beyond age 75 years. Using a single birth cohort, age was excluded as confounding factor. In the baseline investigations in the Danube Hospital, 606 individuals took part and were examined completely at baseline. After 60 months, 508 patients were re-examined. Each participant underwent an indepth investigation with the duration of 7 h, including neuropsychological testing, as well as analyses of biochemical, clinical chemical and genetic parameters, and magnetic resonance imaging (MRI) of the brain. In the present study, only a history of cerebral and cardiovascular events at the baseline or smoking was associated significantly with the appearance of CVDs. In a multiple model both risk factors—history of cerebral and cardiovascular events at the baseline (p = 0.0003, OR 2.36, 95% CI 1.49–3.76) and smoking (p = 0.0005, OR 1.57, 95% CI 1.22–2.03)—remained significant. However, the predictive value of this assessment model was low. The rescaled r 2 of the model was 0.088. A significant correlation was found only between exposure to cigarette smoke or a history of previous CVDs, such as stroke or myocardial infarction. Smoking or earlier CVDs greatly increase the risk for further cerebral and cardiovascular events in persons after 75 years.

In this contribution we show how to find y(x) in the polynomial equation y(x)p ≡ t(x) mod f(x), where t(x), y(x) and f(x) are polynomials over the field GF(pm). The solution of such equations are thought for in many cases, e.g., for p e 2 it is a step in the so-called Patterson Algorithm for decoding binary Goppa codes.

Kritiker meinen, Audi in Ingolstadt hatte sich mit der Anbauteile-Lackierung in Wagenfarbe im eigenen Werk neue Probleme ins Haus geholt. Fachleute von Audi fassen im folgenden Beitrag die Erfahrungen aus uber zwei Jahren Praxis zusammen und ziehen Resumee.

The sodium salt of polyacrylic acid (NaPA) precipitates in the presence of Ca2+-ions. This phase behaviour can be represented by a phase diagram where the critical NaPA concentration is plotted versus the critical Ca2+ concentration resulting in a straight line as a phase boundary. The location of this phase boundary is influenced by the presence of an inert monovalent salt like NaCl. The present contribution focuses on the coil dimensions of NaPA chains in dilute aqueous solution corresponding to the one phase region of such a phase diagram. A variety of parameters with which the size and shape of the polyelectrolyte chains can be modulated are revealed. Approaching the phase boundary by decreasing the NaPA concentration at a constant Ca2+ content leads to a collapse of the NaPA chains. Combined static and dynamic light scattering suggests a compact spherical shape as the final state of this transition, both in 0.1 M NaCl and in 0.01 M NaCl. In the lower NaCl concentration, indication is presented for the existence of a cigar or pearl necklace like intermediate. Most strikingly, the collapsed chains can be reexpanded by increasing the concentration of inert NaCl at constant content of NaPA and Ca2+. Clearly, excessive Na+-ions displace the Ca2+-ions from the NaPA chains.

In this contribution the MacWilliams theorem is stated for codes over finite fields with two-dimensional modulo metrics.

Eichenauer and Lehn's inversive congruential pseudorandom number generator is generalized for arbitrary composite moduli. The maximal period is determined and simple constructive methods are given to find parameters for these generators.

Background Since it is impossible to sequence the complete CFTR gene routinely, clinical laboratories must rely on test systems that screen for a panel of the most frequent mutations causing disease in a high percentage of patients. Thus, in a cohort of 257 persons that were referred to our laboratory for analysis of CF gene mutations, reverse line probe assays for the most common CF mutations were performed. These techniques were evaluated as routine first-line analyses of the CFTR gene status. Methods DNA from whole blood specimens was extracted and subjected to PCR amplification of 9 exons and 6 introns of the CFTR gene. The resulting amplicons were hybridised to probes for CF mutations and polymorphisms, immobilised on membranes supplied by Roche Molecular Systems, Inc. and Innogenetics, Inc.. Denaturing gradient gel electrophoresis and sequencing of suspicious fragments indicating mutations were done with CF exon and intron specific primers. Results Of the 257 persons tested over the last three years (referrals based on 1) clinical symptoms typical for/indicative of CF, 2) indication for in vitro fertilisation, and 3) gene status determination because of anticipated parenthood and partners or relatives affected by CF), the reverse line blots detected heterozygote or homozygote mutations in the CFTR gene in 68 persons (26%). Eighty-three percent of those affected were heterozygous (47 persons) or homozygous (10 persons) for the ΔF508 allele. The only other CF-alleles that we found with these tests were the G542X allele (3 persons), the G551D allele (3 persons), the 3849+10kb C-T allele (2 persons) the R117H allele (2 persons) and the 621+1G-T allele (1 person). Of the fifteen IVS8-5T-polymorphisms detected in intron 8, seven (47%) were found in males referred to us from IVF clinics. These seven 5T-alleles were all coupled with a heterozygous ΔF508 allele, they make up 35% of the males with fertility problems (20 men) referred to us. Conclusions In summary, the frequency of CF chromosomes in the cohort examined with these tests was 26%, with the ΔF508 allele affecting 83% of the CF chromosomes. It is a substantial improvement for routine CF diagnostics to have available a test system for 30 mutations plus the polypyrimidine length variants in intron 8. Our results show that this test system allows a routine first-line analyses of the CFTR gene status.

Within the framework of a remote sensing programme, infra-red scanning sensors were investigated, in a test area in the German Bight, to see how far they are suitable for providing sea surface temperature distributions with sufficient accuracy.

Vertical temperature traces in the north-western Mediteranean show remarkably leafy structures at depths between 100 m and 300 m. The individual layers are stable over several days. Their horizontal extension is larger than 20 nm. The thickness amounts to 25–50 m. It is suggested that these interleavings of slightly different water masses are due to lateral mixing processes in the vicinity of the working area.