α-Alumina and spinel react into single-phase high-alumina spinel in <3 seconds during flash sintering

In situ X-ray diffraction measurements at the Advanced Photon Source show that α-Al₂O₃ and MgAl₂O₄ react nearly instantaneously and completely, and nearly completely to form single-phase high-alumina spinel during voltage-to-current type of flash sintering experiments. The initial sample was constituted from powders of α-Al₂O₃, MgAl₂O₄ spinel, and cubic 8 mol% Y₂O₃-stabilized ZrO₂ (8YSZ) mixed in equal volume fractions, the spinel to alumina molar ratio being 1:1.5. Specimen temperature was measured by thermal expansion of the platinum standard. These measurements correlated well with a black-body radiation model, using appropriate values for the emissivity of the constituents. Temperatures of 1600-1736°C were reached during the flash, which promoted the formation of alumina-rich spinel. In a second set of experiments, the flash was induced in a current-rate method where the current flowing through the specimen is controlled and increased at a constant rate. In these experiments, we observed the formation of two different compositions of spinel, MgO•3Al₂O₃ and MgO•1.5Al₂O₃, which evolved into a single composition of MgO•2.5Al₂O₃ as the current continued to increase. In summary, flash sintering is an expedient way to create single-phase, alumina-rich spinel.     

Aktuelle Aktivitäten zu den europäischen Rohstoff-Initiativen

The European Initiatives manifested in the Communications of the European Commission on Raw Materials, in the Strategic Implementation Plan of the European Innovation Partnership on Raw Materials and in the 2014 Call of the European Institute for Innovation & Technology (EIT) for a Knowledge and Innovation Community (KIC) on Raw Materials lead to manifold Austrian activities on Government level and on level of the Montanuniversitaet Leoben. The ESEE Region, thus East- and Southeast Europe has a special role.     

Increased HDL Size and Enhanced Apo A-I Catabolic Rates Are Associated With Doxorubicin-Induced Proteinuria in New Zealand White Rabbits

The catabolism and structure of high‐density lipoproteins (HDL) may be the determining factor of their atheroprotective properties. To better understand the role of the kidney in HDL catabolism, here we characterized HDL subclasses and the catabolic rates of apo A‐I in a rabbit model of proteinuria. Proteinuria was induced by intravenous administration of doxorubicin in New Zealand white rabbits (n = 10). HDL size and HDL subclass lipids were assessed by electrophoresis of the isolated lipoproteins. The catabolic rate of HDL‐apo A‐I was evaluated by exogenous radiolabelling with iodine‐131. Doxorubicin induced significant proteinuria after 4 weeks (4.47 ± 0.55 vs. 0.30 ± 0.02 g/L of protein in urine, P < 0.001) associated with increased uremia, creatininemia, and cardiotoxicity. Large HDL2b augmented significantly during proteinuria, whereas small HDL3b and HDL3c decreased compared to basal conditions. HDL2b, HDL2a, and HDL3a subclasses were enriched with triacylglycerols in proteinuric animals as determined by the triacylglycerol‐to‐phospholipid ratio; the cholesterol content in HDL subclasses remained unchanged. The fractional catabolic rate (FCR) of [¹³¹I]‐apo A‐I in the proteinuric rabbits was faster (FCR = 0.036 h^?1) compared to control rabbits group (FCR = 0.026 h^?1, P < 0.05). Apo E increased and apo A‐I decreased in HDL, whereas PON‐1 activity increased in proteinuric rabbits. Proteinuria was associated with an increased number of large HDL2b particles and a decreased number of small HDL3b and 3c. Proteinuria was also connected to an alteration in HDL subclass lipids, apolipoprotein content of HDL, high paraoxonase‐1 activity, and a rise in the fractional catabolic rate of the [¹³¹I]‐apo A‐I.     

Migrant Mothers: Richard Harrington’s Indigenous ‘Madonnas’

Canadian photographer Richard Harrington has been recognised since the 1950s for his photographs of the Arctic, and specifically for portraits of the Padleimiut taken at a hunting camp in 1950 during a winter of acute shortages. Three were selected for Edward Steichen’s The Family of Man (1955). Of that group, two focused on motherhood through depictions of childbirth and maternal love; the latter is sometimes referred to as ‘Canada’s Madonna and Child’, making a timeless secular icon from the representation of a crisis. Harrington was a documentary photographer who made his living as a freelance photojournalist specialising in human interest stories and travel features for magazines and newspapers. On assignment in British Columbia for the Hudson’s Bay Company magazine The Beaver, he photographed a First Nations mother and child, an image entitled ‘Madonna of the Peace’. This photograph later graced the cover of a Roman Catholic missionary magazine, Pôle et Tropiques. This article draws parallels between Harrington’s photographs of Indigenous mothers and children and Dorothea Lange’s Migrant Mother, using Harrington’s diaries and community-based research to reconstruct the lives of his subjects, and considering the sacrifice of knowledge to iconicity.     

Fabrication of nanocrystalline LaFeO3: An efficient sol–gel auto-combustion assisted visible light responsive photocatalyst for water decomposition

Synthesis of nano photocatalysts, LaFeO₃ with orthorhombic perovskite structure by sol–gel auto-combustion method was demonstrated. The samples were characterized by PXRD, SEM, HRTEM, XPS and optical absorption studies. Photocatalytic water decomposition over LaFeO₃ nanoparticles activated at various temperatures without any co-catalyst were investigated under visible light irradiation (λ >> 420 nm). Highest amount of H₂ and O₂ evolved in 180 min over the LaFeO₃ activated at 500 °C was recorded to be 1290 μmol and 640 μmol, respectively having apparent quantum efficiency (AQE) 8.07%. The pronounced activity of nano LaFeO₃ samples towards water decomposition was consistent with BET-surface area and particle size analyses.     

Effect of pulsed ultraviolet light on quality of sliced ham

While the efficacy of PUV-light on microbial inactivation is well documented, its effect on product quality is not well studied. Thus the effect of PUV-light on color, texture and oxidative stability of ham was evaluated. Samples of 100 g raw ham (～5 mm thick) were treated for 60, 90 and 120 s in a UV-light system. Another 100 g of untreated sample was used as a control. The distance from the lamp central axis was varied at 4.5, 8.3 and 14.6 cm. Results showed that the oxidative stability of the control, 4.5 cm/60 s, 4.5 cm/90 s, 4.5 cm/120 s, 8.3 cm/60 s, 8.3 cm/90 s, 8.3 cm/120 s, 14.6 cm/60 s, 14.6 cm/90 s, and 14.6 cm/120 s sample decreased by 21, 67, 53, 54, 39, 71, 75, 56, 58, and 55% respectively after 14 days of storage. Oxidative stability reduction was higher as treatment time was prolonged, but decreased with increased distance from the lamp. Overall, the color and texture of the samples were inversely affected by treatment time and distance of the sample from the lamp. Although PUV-light has a potential to decontaminate food products, this study demonstrated that quality of the product is concurrently compromised.     

The role of docosahexaenoic acid in retinal function

An important role for docosahexaenoic acid (DHA) within the retina is suggested by its high levels and active conservation in this tissue. Animals raised on n-3-deficient diets have large reductions in retinal DHA levels that are associated with altered retinal function as assessed by the electroretinogram (ERG). Despite two decades of research in this field, little is known about the mechanisms underlying altered retinal function in n-3-deficient animals. The focus of this review is on recent research that has sought to elucidate the role of DHA in retinal function, particularly within the rod photoreceptor outer segments where DHA is found at its highest concentration. An overview is also given of human infant studies that have examined whether a neonatal dietary supply of DHA is required for the normal development of retinal function.     

A new input indicator for the assessment of science &; technology research?

Traditional input indicators of research performance, such as research funding, number of active scientists, and international collaborations, have been widely used to assess countries’ publication output. However, while publication in today’s English-only research world requires sound research in readable English, English proficiency may be a problem for the productivity of non-native English-speaking (NNES) countries. Data provided by the Brazilian National Research Council (CNPq) containing the academic profile of 51,223 Brazilian researchers show a correlation between English proficiency and publication output. According to our results, traditional input indicators may fall short of providing an accurate representation of the research performance of NNES developing countries.