Homology modelling and molecular dynamics studies of human placental tissue protein 13 (galectin-13)

The primary structure of the newly sequence analysed placentaltissue protein 13 (PP13) was highly homologous to several membersof the ß-galactoside-binding S-type lectin (galectin)family. By homology modelling, the three-dimensional structureof PP13 was built based on high-resolution crystal structuresof homologues and also their characteristic `jellyroll' foldwas found in the case of PP13. Our model has been depositedin the Brookhaven Protein Data Bank. By multiple sequence alignmentand structure-based secondary structure prediction, we underlinedthe structural similarity of PP13 with its homologues. The secondarystructure of PP13 was identical with `proto-type' galectinsconsisting of a five- and a six-stranded ß-sheet,joined by two     

Total phenolics,flavonoids, anthocyanins and antioxidant activity following simulated gastro-intestinal digestion and dialysis of apple varieties: Bioaccessibility and potential uptake

In the present study, an in vitro model simulating gastrointestinal (GI) digestion, including dialysability, was adapted to assess free soluble polyphenols from apples (four varieties). Results indicated that polyphenol release was mainly achieved during the gastric phase (ca. 65% of phenolics and flavonoids), with a slight further release (<10%) during intestinal digestion. Anthocyanins present after the gastric phase (1.04–1.14 mg/100 g) were not detectable following intestinal digestion. Dialysis experiments employing a semipermeable cellulose membrane, presenting a simplified model of the epithelial barrier, showed that free soluble dialysable polyphenols and flavonoids were 55% and 44% of native concentrations, respectively, being approximately 20% and 30% lower than that of the GI digesta. Similar results were found for the antioxidant capacity of dialysable antioxidants, being 57% and 46% lower compared to total antioxidants in fresh apples (FRAP and ABTS test, respectively). It is suggested that some polyphenols are bound to macromolecular compounds that are non-dialysable, that the presented method allowed the study of free soluble polyphenols available for further uptake, and that both chemical extraction and concentrations in final digesta would overestimate polyphenol availability.     

Aging of HTPB/Al/AP Rocket Propellant Formulations Investigated by DMA Measurements

Three HTPB‐based rocket propellant formulations containing ammonium perchlorate and aluminum particles, with different aluminum content and particle size, have been manufactured. The study has focused on the change of mechanical properties with aging time by using dynamic mechanical analysis (DMA). Therefore, propellant formulations underwent an accelerated aging program, in air (RH<10 %), between 60 °C and 90 °C with aging time adjusted to a thermal equivalent load of 15 to 20 years at 25 °C. DMA investigations revealed distinct changes in the shape of the loss factor curve. These curves were modeled with three exponentially modified Gaussian (EMG) functions in order to get the molecular interpretation of the involved aging phenomena by separating the binder fractions with different mobility. Aging of propellant formulations can be followed by considering only two parameters: the areas of the second and third loss factor transition peaks (A₂, A₃), and the corresponding maximum temperature values of the assigned Gauss peaks (Tc₂, Tc₃).     

Nanofluidic injection and heterogeneous kinetics of organomercaptan surface displacement reactions on colloidal gold in a microfluidic stream

Colloidal gold is developed as a molecular capture reagent in hybrid nanofluidic-microfluidic devices for mass-limited sample analysis. Two fluorescent organomercaptans are injected through a nanocapillary array membrane and subsequently captured at the surface of 19-nm-diameter colloidal Au nanoparticles. The surface displacement kinetics are monitored via quenching of the organomercaptan fluorescence by the metallic particles coupled to a distance-time conversion based on fluid velocity in the microfluidic channel using the point of mixing as the zero of time. The adsorbate concentration, colloid concentration, and fluid velocity are varied to determine the surface displacement rate constants for these heterogeneous reactions in the microfluidic device. Surface displacement rate constants are approximately 10(4) M(-1) s(-1) for a small organic molecule and for an octapeptide. These values are similar to values determined in macroscale measurements made with a traditional fluorometer and are 1 order of magnitude larger than values reported for adsorption of organomercaptans on planar Au, indicating faster kinetics in the colloid-adsorbate system. These results highlight the utility of colloidal Au nanoparticles as molecular carriers for the sequestration of analytes, allowing the manipulation of mass-limited samples and ultimately the capture and delivery of selected analytes from a microfabricated device to an off-line detector.     

3-D CONJUGATE ANALYSIS OF COOLED COATED PLATES AND HOMOGENIZATION OF THEIR THERMAL PROPERTIES

To predict the aerothermal behavior of a transpiration cooled plate, a multiscale approach based on the homogenization method of periodic material structures is presented here. This method allows calculation of effective equivalent thermophysical properties either for each layer or for the multilayer of superalloy, bondcoat, and thermal barrier coating (TBC). From the 3-D conjugate flow and heat transfer analysis, the stationary state is extracted and transferred to the microscale unit cell discretized by finite elements. The analysis proves for different cooling configurations a significant decrease in the amount of cooling fluid to obtain a desired superalloy temperature. Beyond, the hole outlet shaping leads to a reduction of the thermal gradients on the multilayer. The effect of the different cooling designs on the effective conductivities are discussed then. Finally, the influence of the selection of the unit cell position on these effective thermal properties is investigated.     

Microstructure Heat Exchanger Applications in Laboratory and Industry

In this article, heat transfer in microstructure devices and its application in laboratory and industry will be described. Basic principles of microstructure heat exchangers made of metal, ceramics, and polymers will be presented. A variety of laboratory prototype applications will be shown, as well as some examples for industrial use of not only microstructure heat exchangers, but also microstructure devices as chemical reactors. A brief outlook will describe possible future application fields.     

Oxidation of copper-manganese alloys under pure oxygen

Oxidation, in oxygen gas at atmospheric pressure, of copper-manganese alloys (Mn content less than 40 at.%) has been investigated between 600 and 850° C. The reaction kinetics, determined by thermogravimetry, follow a parabolic law for alloys having a low manganese content (less than 10 at.% Mn) but are more complex for higher concentrations, particularly in the first stages of the oxidation process. Whereas in the early stages of oxidation the kinetics are controlled by surface reactions which accompany the formation of the different oxide layers, they are later controlled by the diffusion of a mobile species when the parabolic law is followed. In this condition an apparent activation energy may be determined from the rate constants. These energies are of the order of 120–140 kJ mol^–1, comparable with that for oxidation of pure copper (134 kj mol^–1), indicating a similar oxidation mechanism.The oxide layers formed were identified by cross-checking results of X-ray diffraction, electron microprobe analysis, and from glow discharge spectrometry. External layers of CuO and Cu₂O formed on alloys of lower manganese concentration, evolving towards one or several mixed copper-manganese oxide layers with increasing manganese content. Under the external layers, which were weakly adherent to the sample, an internal-oxidation layer formed, which was adherent and consisted of precipitates of Mn₃O₄/MnO dispersed in the copper lattice. For alloys richer in manganese (36 at. % Mn) and at temperatures above 850°C (20 at.% Mn), the internal-oxidation layer evolved into two zones: MnO particles beneath a zone of Mn₃U₄ particles.     

Expression of glucocorticoid and mineralocorticoid receptors in an immortalized hippocampal neuronal cell line

A clonal cell line of rat embryonic hippocampal origin (H19-7) has been examined for the expression of glucocorticoid receptors (GR) and mineralocorticoid receptors (MR). H19-7 cells grown at 33 degrees C continue to divide, however when grown at 39 degrees C in reduced levels of serum the cells undergo morphological differentiation and express neuronal properties. Immunocytochemistry demonstrated that H19-7 cells express both MR and GR when grown at either 33 degrees C or 39 degrees C. GR mRNA is readily detected in H19-7 cells by RNase protection assay. MR mRNA levels in H19-7 cells are too low to detect by RNase protection, but can be detected by RT-PCR. RT-PCR also demonstrated that H19-7 cells express more GR mRNA than primary hippocampal neurons. Since previous studies have shown that the level of MR mRNA is higher than that of GR mRNA in hippocampal neurons, these studies suggest that H19-7 cells represent hippocampal neurons immortalized at an early stage when the MR system is not yet fully differentiated.     

MoneyBee: Aktienkursprognose mit künstlicher intelligenz bei hoher rechenleistung

The company i42 GmbH, Mannheim, developed MoneyBee: a system to predict stock market values, basing on artificial intelligence (neural networks), distributed computing and different applications to optimize the input- and output-data (e.g. genetic algorithms, statistical methods). More than 200 values (especially from German stock market) are observed by this system continuously, with daily updated predictions. The information technology product is an innovation — not by its basic technology, but by its cooperation of different program groups on high level.