831 research outputs found
Application of Texture Analysis technique in formulation development of lyophilized orally disintegrating tablets containing mannitol, polyvinylpyrrolidone and amino acids
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Orally disintegrating tablets (ODTs) attract a great attention as this easy swallowing dosage form often improves patient compliance. In the current work, orally disintegrating tablets comprising mannitol, polyvinylpyrrolidone (PVP) and an amino acid (alanine, glycine or serine) with various PVP-to-amino acid ratios were formulated. The combination of mannitol and an amino acid was aimed to use the advantages of mannitol, the matrix-supporting and disintegration agent, and to reduce the total amount of sugar/polyol in tablets. Tablets were manufactured by freeze-drying and their properties (appearance, internal structure, disintegration, mechanical and texture properties, moisture uptake, shrinkage, thermal properties) were assessed. In the work, great emphasis was placed on illustrating the applicability of the Texture Analysis of the freeze-dried cakes directly in vials in formulation development. The results show that the appearance, mechanical properties, disintegration and shrinkage of the freeze-dried ODTs depend significantly on the excipient composition with PVP playing the leading role. Partial mannitol replacement with an amino acid has a limited impact on the tablet properties. The presence of an amino acid also has no impact on the PVP-mannitol interaction. The mechanical and texture properties of freeze-dried ODTs depend non-linearly on the PVP content. The transition between the different types of textures occurs in a narrow range of PVP concentrations regardless of the type of amino acid in a formulation. The non-linear effect of PVP on various tablet properties should be taken into account when designing ODT formulations as it can compromise the robustness of the manufacturing process
Pathorganic
Risks and Recommendations Regarding Human Pathogens in Organic Vegetable Production Chains
99 cent: Price points in e-commerce
Basu (2006) argues that the prevalence of 99 cent prices in shops can be explained with rational consumers who disregard the rightmost digits of the price. This bounded rational behaviour leads to a Bertrand equilibrium with positive markups. We use data from an Austrian price comparison site and find results highly compatible with Basu's theory. We can show that price points - in particular prices ending in 9 - are prevalent and have significant impact on consumer demand. Moreover, these price points are sticky; neither the price-setter itself wants to change them neither the rivals do underbid these prices, if they represent the cheapest price on the market. --Competitive Behaviour,Pricing Behaviour,E-Commerce,Pricing in the Nines,Focal Pricing
99 cent: Price Points in E-Commerce
Basu (2006) argues that the prevalence of 99 cent prices in shops can be explained with rational consumers who disregard the rightmost digits of the price. This bounded rational behaviour leads to a Bertrand equi- librium with positive markups. We use data from an Austrian price com- parison site and find results highly compatible with Basu's theory. We can show that price points - in particular prices ending in 9 - are preva- lent and have significant impact on consumer demand. Moreover, these price points are sticky; neither the price-setter itself wants to change them neither the rivals do underbid these prices, if they represent the cheapest price on the market.e-commerce, price comparison, price policy
Comment on "Zeeman-Driven Lifshitz Transition: A Model for the Experimentally Observed Fermi-Surface Reconstruction in YbRh2Si2"
In Phys. Rev. Lett. 106, 137002 (2011), A. Hackl and M. Vojta have proposed
to explain the quantum critical behavior of YbRh2Si2 in terms of a
Zeeman-induced Lifshitz transition of an electronic band whose width is about 6
orders of magnitude smaller than that of conventional metals. Here, we note
that the ultra-narrowness of the proposed band, as well as the proposed
scenario per se, lead to properties which are qualitatively inconsistent with
the salient features observed in YbRh2Si2 near its quantum critical point.Comment: 3 page
Electron-boson glue function derived from electronic Raman scattering
Raman scattering cross sections depend on photon polarization. In the
cuprates nodal and antinodal directions are weighted more strongly in
and symmetry, respectively. On the other hand in angle-resolved
photoemission spectroscopy (ARPES), electronic properties are measured along
well-defined directions in momentum space rather than their weighted averages.
In contrast, the optical conductivity involves a momentum average over the
entire Brillouin zone. Newly measured Raman response data on high-quality
BiSrCaCuO single crystals up to high energies have
been inverted using a modified maximum entropy inversion technique to extract
from and Raman data corresponding electron-boson spectral
densities (glue) are compared to the results obtained with known ARPES and
optical inversions. We find that the spectrum agrees qualitatively
with nodal direction ARPES while the looks more like the optical
spectrum. A large peak around meV in , much less prominent
in , is taken as support for the importance of scattering
at this frequency.Comment: 7 pages, 3 figure
Market structure and market performance in E-commerce
We investigate the effect of market structure on market performance in the market for consumer electronics. We exploit product life cycle information to build an instrumental variable for the number of firms in a market, a variable which hitherto had to be treated as exogenous in comparable studies on seller-behavior in e-commerce. We combine data from Austria´s largest online site for price comparisons with retail data on wholesale prices provided by a major hardware producer for consumer electronics. We observe input prices of firms, and all their moves in the entry and the pricing game. Using this information for 70 digital cameras, we generate instrumenting is particularly important for estimating the effect of competition on the markup of the price leader
Entry, exit, and pricing strategies at online price-comparison sites : do price markups fall by themselves, or is competition crucial?
Immer mehr Menschen gehen beim Surfen im World Wide Web auf Einkaufstour. Dabei geben Preisvergleichsseiten oftmals hilfreiche Tipps, wo das gesuchte Produkt am gßnstigsten zu haben ist. Dass sich ein Vergleich lohnt, zeigt eine Studie des Zentrums fßr Europäische Wirtschaftsforschung (ZEW) Mannheim und der Universität Linz. Die Studie kommt zu dem Ergebnis, dass bereits zehn zusätzliche Anbieter des gleichen Produkts den Preisaufschlag des gßnstigsten Anbieters um 1,7 Prozentpunkte verringern
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