Structure and properties of 6061 + 26 mass% Si aluminum alloy produced via coupled rapid solidification and KOBO-extrusion of powder

Experiments on mechanical consolidation of rapidly solidified (RS) powder of 6061 + 26 mass% Si alloy were performed using the oscillating-die extrusion method. The RS powder was wrapped in thin-wall 6061-alloy cup 35 mm in diameter and vacuum-compressed by means of 100 ton press. Bars 8 mm in diameter were extruded with cross-section reduction of λ = 19 without any preheating of the charge. Tubes with a diameter/wall thickness of 14 mm/1 mm and cross-section reduction of λ = 33 were also manufactured with success. TEM/STEM observations revealed a very fine structure of as-extruded material and bimodal distribution of quasi-spherical silicon particles. Statistical analysis revealed a silicon fine fraction of 0.1–0.7 μm and a coarse fraction 2.1–2.5 μm in diameter. Examination by means of TEM did not reveal any significant changes in the morphology of the silicon particles, even when a high extrusion ratio and the material annealing after deformation were used. Hot compression tests on as-extruded rods (λ = 19) and preliminary annealed samples were performed at a constant true strain rate of 5 × 10^?3 s^?1 within the temperature range of 293–823 K. High strength of the material and relatively high ductility of samples deformed by compression up to ?_t ? 0.4 were observed. The maximum flow stress value for as-extruded material was reduced with deformation temperature from ～390 to ～3.5 MPa for 293 and 823 K, respectively. Annealing of the samples at 773 K/30 min was found to reduce the maximum flow stress by 30–40%. Tensile strengths of similar as-cast alloys and materials manufactured by means of other powder metallurgy methods were shown for the purpose of comparison.     

Relationship between endocrine, immune, and clinical variables in patients with systemic lupus erythematosus

OBJECTIVE: To assess the frequency of increased plasma prolactin (PRL) in patients with systemic lupus erythematosus (SLE) and to evaluate its relationship to other hormonal and immune variables. METHODS: Thirty-five patients with SLE with various levels of disease activity were studied. Plasma PRL, cortisol, growth hormone (GH) were determined by radioimmunoassay and interleukin 6 (IL-6) by ELISA: SLE activity was evaluated using the European Consensus Lupus Activity Measurement (ECLAM). RESULTS: Increased plasma PRL concentration (> 20 ng/ml) was recorded in 11 patients (31%). No correlation was found between plasma PRL and GH, IL-6, cortisol, or C-reactive protein, nor was any significant correlation observed between plasma PRL and the ECLAM score. Patients with hyperprolactinemia were, however, found to have been treated with higher doses of prednisone therapy than patients with normal plasma PRL. Further analysis of the relationship of plasma PRL and therapy showed that patients with SLE selected by the attending physician for prednisone therapy in doses > or = 10 mg/day were more frequently hyperprolactinemic. CONCLUSION: Our findings that patients with SLE with a more active form of the disease and who are less responsive to therapy had increased plasma PRL levels more frequently may be indicative of a potential relationship of hyperprolactinemia to severity of disease.     

Adverse effects of calcium binding contrast agents in diagnostic cardiac angiography. A comparison between formulations with and without calcium binding additives

RATIONALE AND OBJECTIVES: The authors compared complications and hemodynamic and electrophysiologic effects of two formulations of diatrizoate, one with additives that bind calcium and one without, in diagnostic cardiac angiography. METHODS: Two hundred twenty-three consecutive low-risk patients alternately received Hypaque 76 (group 1, little calcium binding effect), and MD 76 (group 2, significant calcium binding). Electrocardiographic and hemodynamic changes related to coronary angiography and left ventriculography were measured, and complications requiring treatment were recorded. RESULTS: There were more complications in patients in group 2 than in group 1 (18 versus 8, P = 0.04). Arterial pressure fell more, the QT interval increased more, and the heart rate fell more in group 2 after coronary angiography. CONCLUSIONS: Formulations of diatrizoate that minimize calcium binding are advocated for cardiac angiography when using high osmolality contrast media. The more detrimental effects that calcium binding has on myocardial function and cardiac conduction may lead to the higher incidence of complications.     

Association of metabolic syndrome risk factors with selected markers of oxidative status and microinflammation in healthy omnivores and vegetarians

Conditions predisposing to metabolic syndrome (MetS) are associated with increased oxidative stress and inflammation. We studied, in vegetarians (n = 90) and omnivores (n = 46), the impact of the dietary regimen on the occurrence of MetS risk factors (RFs: BMI, blood pressure, glucose metabolism and lipid profile) in relation to oxidative status (advanced glycation end products (AGEs), advanced oxidation protein products (AOPPs), malondialdehyde, ferric reducing ability of plasma, vitamins A, E, C, beta-carotene and superoxide dismutase activity) and microinflammation (C-reactive protein, leukocytes and neopterin). The proportion of subjects without/positive for one or two MetS RFs was comparable between the groups. From the components of MetS only immunoreactive insulin levels differed significantly (95% CI: omnivores: 5.0-7.1 microU/mL, vegetarians: 4.5-5.4, p = 0.03). Omnivores had lower AOPP (omnivores: 0.29-0.36 micromol/g albumin, vegetarians: 0.36-0.52, p = 0.01) and beta-carotene levels than vegetarians, they consumed more calories, proteins, fat and saturated fatty acids, and less fibres, beta-carotene and vitamin C. Multiple regression analysis revealed vitamin E and AOPP levels as the most important independent determinants of MetS RFs. The vegetarian diet seems to exert beneficial effects on MetS RFs associated microinflammation. Whether the vegetarian diet may counteract the deleterious effects of elevated AOPPs and AGEs, remains to be elucidated.     

Untersuchungsergebnisse über Sonnenblumen

Studies on Sunflower The results of long-term studies on breeding of Hungarian and Russian sunflower varieties in Hungary are reported and discussed. These studies were concerned with the amino acid composition of sunflower protein and fatty acid composition of sunflower oils. Moreover, the ratio of hull to kernel, distribution of moisture between hull and kernel, wax content and the composition of the ash from sunflower hull after industrial combustion were determined. Further work was concerned with tocopherol and sterol content as well as glycerid structure of the oils extracted from Hungarian and Russian varieties of sunflower.     

Stochastic stability of a plate in a magnetic field

Summary The almost sure asymptotic and the uniform stochastic stability of a rectangular, beam-like, conducting plate in an exterior, normal to the plate middle surface magnetic field are investigated. The plate is simply supported on the two opposite edges and subjected to time-varying compressing forces which are assumed to be Gaussian stochastic processes. The problem is solved by means of the direct Liapunov functionals method. The uniform stability and the almost sure asymptotic stability regions are obtained for white and non-white compressing processes respectively. The influence of material magnetic properties on the stability regions is investigated.With 4 Figures     

Study on utilizing solid food industry waste with brewers' spent grain and potato pulp as possible peroxidase sources

This study found that extracts containing ionically bound proteins, isolated from potato pulp and brewers' spent grain, were characterized by high peroxidase activities. The kinetic parameters, namely K_m and V_max values, were typical for plant peroxidases. Seven peroxidase isoenzymes in potato pulp and two isoenzymes in brewers' spent grain were obtained from their respective ionically bound fractions. Peroxidases from both potato pulp and brewers' spent grain displayed high storage stability, over a 90‐day‐long storage period, if stored at ?20°C with glycerol added to a concentration of 50% or as unsupplemented extracts at 4°C. Peroxidase activity was present in the covalently bound fraction of potato pulp, whereas it was absent in the respective fraction of brewers' spent grain. Covalently bound peroxidases from potato pulp displayed high activity, but low stability. Peroxidases extracted from brewers' spent grain and potato pulp, followed the ping‐pong mechanism and the sequence mechanism, respectively.

Practical applications

Plant peroxidases are widely applicable in various fields of biotechnology and diagnostics. These enzymes are used for biosensor and glucometer construction and in conjugation with antibodies for the purpose of enzyme immunoassays. Using waste products as a peroxidase source provides a cost‐friendly alternative to commercially available horseradish peroxidase and gives an opportunity to recycle waste from the food industry—processed plant biomass. Here, the properties of peroxidases from food waste products, namely potato pulp and brewers' spent grain are analyzed. The extracts were characterized by high storage stability and high enzymatic activity, which are two key traits necessary for the practical use of enzyme preparations.     

Züchtung von erucasäurefreiem Raps in Ungarn

Breeding of Zero-Erucic Rape in Hungary The latest results of rape breeding in Hungary are discussed with reference to the characteristics of winter rape (Brassica napus) currently grown in Hungary. For the breeding of new varieties of rape, zero-erucic varieties of Canadian and Polish origin were used in addition to those of Hungarian origin. Cross breeding of the aforesaid varieties yielded a zero-erucic line (IR-0) and a low-erucic line (IR-1). The characteristics of these new varieties are reported. The new varieties are currently being tested in Government laboratories. The results obtained so far show many favourable properties of the new varieties.     

Verteilung der Linolsäure in den Glyceriden unter besonderer Berücksichtigung der ß-Stellung

Partition of Linoleic Acid in Glycerides in Special Consideration of β-position The authors valuate the quantitative partition of linoleic acid in β- and α,α′-position of triglycerides of some natural fats and oils with reference to the influence of autoxidation using the available literature data and own experimental results. Basing on the valuation they differenciate between the following three types: 1, at high linoleic acid content a high linoleic acid content in β-position, too, 2. at low linoleic acid content a high content in β-position, 3. at low linoleic acid content also low content in β-position.     

Analytical travel time models for multi aisle automated storage and retrieval systems

Multi aisle automated storage and retrieval systems correspond to multiple picking aisles served by a single storage and retrieval machine. These systems are used in practice when the need for pallet places is high and the throughput capacity is relatively low. Therefore, considerable savings of initial investment costs due to single aisle systems can be achieved using such systems. The objective of the presented study is to develop analytical travel time models for multi aisle automated storage and retrieval systems considering the operating characteristics of the storage and retrieval machine. With the proposed analytical travel time models, average travel time of the storage and retrieval machine, from which the performance of multi aisle automated storage and retrieval systems can be evaluated is determined. A simulation model of multi aisle automated storage and retrieval systems was developed to compare the performances of the proposed analytical travel time models. An example of multi aisle automated storage and retrieval systems with five picking aisles was presented for the evaluation purpose. The results show that proposed analytical travel time models perform satisfactory according to the results of simulation analysis and could be very useful tools for designing of multi aisle automated storage and retrieval systems in real-world applications.