IMPROVED PROPERTIES OF THE MAGNESIUM BASED ALLOY MSR

The low density of magnesium alloys makes them attractive for the use in light weight construction in the automotive and aerospace industries. The deficiencies of the mechanical properties frequently prevent these alloys from competing with aluminum alloys. The concept of THERMOMECHANICAL TREATMENT offers the opportunity of developing the full potential of commercial magnesium alloys. This forms the background of the investigations reported in this paper which attempts to show the beneficial effects of such processes on select mechanical properties.     

The impact of negative affect on autobiographical memory: the role of self-focused attention to moods

Five studies examined how self-focused attention affects the impact of negative moods on autobiographical memory. It was proposed that self-focused attention to moods may increase the likelihood of both mood-congruent recall and mood-incongruent recall and that the type of recall effect that occurs will depend on the manner in which people focus on their moods. In these studies, participants were led to experience negative or neutral moods, exposed to a manipulation designed to affect some aspect of their attention to their moods, and then asked to report memories. This research revealed that when people adopt a reflective orientation to their moods, they are more likely to engage in mood-incongruent recall; in contrast, when they adopt a ruminative orientation to their moods, they are more likely to engage in mood-congruent recall. Thus, the way in which people focus on their moods moderates the relation between mood and memory.     

Wasserbindungskapazit?t und Makrostruktur von Apfelgewebepartikeln

Zusammenfassung Haufwerke aus trockenen Apfelgewebepartikeln mit mittleren Partikelvolumina zwischen 0,3 und 5 mm³ können bis zu 80 g/g Wasser aufnehmen. Der überwiegende Teil dieses Wassers ist in makrocapillaren Haufwerks- und Partikelhohlräumen eingelagert und nur durch sehr geringe Kräfte gebunden. Bereits bei Einwirkung eines Gasdrucks von 2 kPa werden die Partikelhaufwerke stark entwässert. Die Wasserbeladung sinkt auf 20-15 g/g. Die Rehydratation einzelner getrockneter Apfelgewebepartikel ist vom Ausmaß der bei der Zerkleinerung eingetretenen Gewebezerstörung abhängig und kann durch eine der Trocknung vorgelagerte Entwässerung mit Ethanol verbessert werden. Vorentwässerte Partikel mit einem hohen Ethanolgehalt schrumpfen bei der Trocknung im geringeren Ausmaß und besitzen eine hohe Porosität. Solche Partikel binden im rehydratisierten Zustand bis zu 30 g/g Wasser. Nicht mit Ethanol behandelte Partikel binden unter 11 g/g Wasser.

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Water binding capacity and macrostructure of apple tissue particles

Samples (bulk materials) of dry apple tissue particles in a range of particle volume from 0.3 to 5 mm³ can absorb up to 80 g/g water. Most of this water is included in macrocapillary bulk and particle spaces and is bound by very small forces. An external gas pressure of 2 kPa decreases the water content to 20-15 g/g. The rehydration properties of single apple tissue particles depend on the degree of tissue disintegration and can be improved by a dehydration treatment with ethanol before drying. Such pre-dehydrated particles with a high ethanol concentration in the liquid phase show little shrinkage during the drying process and have a high porosity. They retain up to 30 g/g water after rehydration. The water uptake of non-ethanol-treated particles is less than 11 g/g.

     

Signature of Man-Made High-Frequency Radio Noise

This paper expands the single sloping line labeled ?man-made noise? in existing atmospheric radio noise predictions. Data taken from the Puget Sound (Seattle) area are developed to show spectral (0.1-10 MHz) and spatial (1-100 miles) man-made radio noise distributions. The effects of soil/saltwater conductivity contrasts and receiver elevation above ground are also considered. Methods of predicting noise contributions from both nearby cities and electric trunk lines are presented.     

Zone melting of indium phosphide

Bulk indium phosphide crystals have been prepared by zone melting with dislocation densities 104 ≤ N_d ≤ 105 cm^-2. The residual impurity level in nominally undoped crystals and the dopant distribution in Cd-, Sn- and Ge-doped zone melted ingots, as revealed by spark source mass spectrometric analyses, indicate a strong interaction between segregation at the solid/liquid interface and vapor transport. The effective distribution coefficients for Sn and Ge in zone melted InP are k_e(Sn) = 0.3 and k_e(Ge) = 0.4. The free electron concentration measured in the middle section of nominally undoped ingots is N_D-N_A = 1.9 × 10¹⁵ cm^-3 corresponding to a Hall mobility Μ_e = 3263 cm^2V-1sec^-l.     

Three generations of cyclosporine a formulations: an in vitro comparison

When the microemulsion formulation of the critical dose drug cyclosporine A (CsA) (Sandimmun Optoral) was introduced in the mid-1990s, it became clear that this new formulation improves the oral bioavailability of CsA and has a positive influence on its pharmacokinetic variability. Previous studies with the original CsA formulation (Sandimmun) showed that the size of the emulsion droplets and concomitant food intake has an effect on the absorption of CsA from the small intestine when orally administered. It was suggested that these effects might have an influence on the drugs' pharmacokinetic parameters.In this study, we focused on the two above-mentioned aspects and compared the first and second generations of CsA products (Sandimmun, Sandimmun Optoral) to generic CsA formulations by analyzing the contents of cyclosporine A gel capsules with respect to their emulsion droplet and micelle sizes using photon correlation spectroscopy (PCS). We tried to discern any differences in droplet size between different generations of CsA formulations, primarily the second and third generation, through simple physical tests. Because a high fat content food may influence the absorption of CsA, we also determined the distribution of CsA between hydrophilic and lipophilic phases using high-performance liquid chromatography analysis.It became clear that when compared under simple physical conditions, established cyclosporine formulations and new generic products show significant differences in droplet size and distribution between an aqueous phase and a high fat content food. Whether these differences are of clinical relevance remains to be investigated.     

Structural and functional characterization of glutaraldehyde-polymerized bovine hemoglobin and its isolated fractions

Glutaraldehyde-polymerized bovine hemoglobin (PolyHbBv, trade name Oxyglobin), is a non-site-specific modified hemoglobin-based oxygen-carrying solution, developed for use in veterinary medicine. PolyHbBv was fractionated into four distinct tetrameric and multiple polytetrameric forms ranging in molecular mass (87.2-502.3 kDa) using size exclusion chromatography (SEC) and verified by laser light scattering. We evaluated the structural modification occurring in the fractionated mixture of PolyHbBv and assessed the functionality and redox stability of each fraction in relation to the mixture as a whole. Intramolecular cross-linking evaluation as performed by MALDI-MS and SEC under dissociating conditions revealed no-site-specific tetramer stabilization within the fractions; Intermolecular cross-linking was highly correlated with lysine and histidine modification as determined by amino acid composition analysis. While native unmodified hemoglobin, HbBv, PolyHbBv, and PolyHbBv fractions (F1-F4) revealed significant methionine oxidation, modification, or both, the critical betaMet55 located in the functionally plastic domains (alpha1-beta1 interface) of HbBv was unaltered. Moreover, neither of the two betaCys93 located in the highly plastic alpha1-beta2 interface were modified in PolyHbBv or in F1-F4. Our structural analysis also revealed that the reported loss in sensitivity to chloride in PolyHbBv could not be attributed to direct alteration of chloride ion binding amino acids. Structural modification imparted by glutaraldehyde resulted in nearly identical functional characteristics of PolyHbBv and its fractions with regard to oxygen equilibrium, ligand binding, and autoxidative kinetics.     

Ferroelasticity in the semiconductor PtGeSe

Orthorhombic PtGeSe, with a = 6.00984 ± 0.00004, b = 6.06174 ± 0.00005 and c = 5.98187 ± 0.00005 Å at 298°K (λCuKα₁ = 1.540562 A), is predicted on the basis of atomic coordinates reported by Entner and Parthé (Acta Cryst. (1973) B29, 1557) to be ferroelastic. Crystals with volume as large as 10 mm³ have been grown at about 1500°K from the elements by unidirectional solidification. The twinning in many as-grown crystals corresponds to interchange among the principal lattice vectors. Uniaxial stress of about 16 MNm^?2 is sufficient to eliminate all but one lattice vector along the stress direction and interchange lattice vectors in single domains. The ferroelastic behavior is accounted for by three independent atomic mechanisms. Some of the resulting atomic displacements, for Ge and Se, are as large as 2 Å. The resistivity of PtGeSe is 8.18×10^?3 ohm-cm at 300°K, 3.21×10^?1 ohm-cm at 4.2°K.