254 research outputs found
Correlation and magma types of the miocene silicic pyroclastic formations in the Bükkalja region, Hungary: a zircon morphology study
AMPEROMETRISCHE, KONDUKTOMETRISCHE UND OSZILLOMETRISCHE BESTIMMUNG DES ALUMINIUMS MIT KUPFERRON MESSLÖSUNG
Whey separation using TiO<sub>2</sub>-modified ultrafiltration membrane
Nowadays, the membrane filtration technique is a commonly used method for the separation of whey. The most significant limitation of membrane applications is fouling, which causes flux decline. During this work, regenerated cellulose membranes covered by TiO2-nanoparticles were investigated and applied to the separation of whey solution. Experiments were carried out in a dead-end ultrafiltration cell, and the changes in filtration parameters and the photocatalytic effects of the UV irradiated TiO2 modified membrane surface on the membrane fouling were examined. Our results showed that the water flux decreased with increasing TiO2 layer thickness, but the retention of turbidity and of COD increased. After separation, the membrane surface was cleaned by UV irradiation by means of photocatalytic oxidation. It was found that the original flux was recoverable, while the retention of the membrane decreased after cleaning
A game changer : exploring and exploiting cloud computing
Even Fortune 500 firms can disappear quickly because many of them fall into an exploitation trap. Examples show that certain organizations – that manifest ambidextrous features – can avoid the exploitation trap. But, how do they manage it? The Authors tracked the digital transformation of a Fortune 500 company in order to understand the strategic and organizational challenges and solutions to becoming resilient and prosperous. A cutting-edge example is shown in the paper about how an industry leader can exploit traditional industry while exploring and exploiting new ones and their markets at the same time. The Authors found that shaping an industry needs strong top-down leadership, and strong alignment between markets, strategy, and the configuration of the firm
HAT-P-13: a multi-site campaign to detect the transit of the second planet in the system
A possible transit of HAT-P-13c has been predicted to occur on 2010 April 28.
Here we report on the results of a multi-site campaign that has been organised
to detect the event. CCD photometric observations have been carried out at five
observatories in five countries. We reached 30% time coverage in a 5 days
interval centered on the suspected transit of HAT-P-13c. Two transits of
HAT-P-13b were also observed. No transit of HAT-P-13c has been detected while
the campaign was on. By a numerical experiment with 10^5 model systems we
conclude that HAT-P-13c is not a transiting exoplanet with a significance level
from 65% to 72%, depending on the planet parameters and the prior assumptions.
We present two times of transit of HAT-P-13b ocurring at BJD 2455141.5522 +-
0.0010 and BJD 2455249.4508 +- 0.0020. The TTV of HAT-P-13b is consistent with
zero within 0.001 days. The refined orbital period of HAT-P-13b is 2.916293 +-
0.000010 days.Comment: 5 pages, 4 figures, to be accepted by A&
Studies on the neurotoxicity of arsenic in rats in different exposure timing schemes
Arsenic has long been recognized as human poison and, more recently, as an essential micronutrient. Here, the effects of low-level arsenic exposure on the central and peripheral nervous system functions were studied in rats, in a 4-8-12-week subchronic exposure scheme, and in a 3-generation scheme involving treatment of the parents and the offspring. From the rats, spontaneous and evoked activity of the sensory cortical areas, and compound action potential from the tail nerve, was recorded in urethane anesthesia, then dissection with organ weight measurement was done. Body weight gain of the treated animals did not differ significantly from the control. There were, however, dose-dependent changes in the weight of the liver and other organs. Latency of the cortical-evoked potentials increased in the treated rats in both schemes. The change was significant after long exposure times and in the higher dose groups. A shift of the spontaneous cortical activity to higher frequencies was also observed, with similar dose- and time dependence. Low-level arsenic affected the behavioral and electrophysiological functions in the brain, indicating that long-lasting arsenic exposure can result in manifest alteration of the central and peripheral nervous system. Consequently, arsenic-exposed populations may have a higher risk of behavioral and functional neurotoxic effects and potentially be an additive to the neurotoxicity of other environmental xenobiotics. Š2006 Dustri-Verlag
Effects of divergent selection for hind leg muscle volume on its lipid peroxide and glutathione redox status, and fatty acid composition in growing rabbits
[EN] Pannon White bucks were selected divergently using CT method by the volume of the hind leg muscle. Animals showed the highest and lowest muscle volumes were selected as minus and plus-selected variants. The male progenies of the minus and plus-selected parents were slaughtered as fi rst generation which was selected again by CT method and the male progenies of the parents were slaughtered. Results in the fi rst and second generation suggest that selection, as a genetic effect did not affect the rate of lipid peroxidation, as was measured by malondialdehyde content and glutathione redox status, as was measured by the reduced glutathione content and glutathione peroxidase activity of the hind leg muscle. However, there were some differences in the fatty acid composition. Significant (P<0.05) difference was found in palmitoleic acid content which was higher in the minus as compared to the plus variants in the second generation, in eicosadienoic acid which was higher in the fi rst as compared to the second generation of minus variants, and total monounsaturated fatty acids which was higher in the minus as compared to the plus variants in the second generation. It means that selection for higher hind leg volume would not causes marked in changes in the rabbit meat quality as measured by lipid peroxide and glutathione status as well as fatty acid composition.Mézes, M.; Balogh, K.; Fébel, H.; Matics, Z.; Fricska, M.; Szabó, A.; Szendro, Z. (2009). Effects of divergent selection for hind leg muscle volume on its lipid peroxide and glutathione redox status, and fatty acid composition in growing rabbits. World Rabbit Science. 17(1):15-19. doi:10.4995/wrs.2009.665151917
- …