Platform Ownership

Lecture on the first SFB/TR 15 meeting, Gummersbach, July, 18 - 20, 2004We develop a general theoretical framework of trade on a platform on which buyers and sellers interact. The platform may be owned by a single large, or many small independent or vertically integrated intermediaries. We provide a positive and normative analysis of the impact of platform ownership structure on platform size. The strength of network effects is important in the ranking of ownership structures by induced platform size and welfare. While vertical integration may be welfare-enhancing if network effects are weak, monopoly platform ownership is socially preferred if they are strong. These are also the ownership structures likely to emerge

Platform Ownership

Lecture on the first SFB/TR 15 meeting, Gummersbach, July, 18 - 20, 2004We develop a general theoretical framework of trade on a platform on which buyers and sellers interact. The platform may be owned by a single large, or many small independent or vertically integrated intermediaries. We provide a positive and normative analysis of the impact of platform ownership structure on platform size. The strength of network effects is important in the ranking of ownership structures by induced platform size and welfare. While vertical integration may be welfare-enhancing if network effects are weak, monopoly platform ownership is socially preferred if they are strong. These are also the ownership structures likely to emerge.Two-Sided Markets; Network Effects; Intermediation; Product Diversity

Переклад у галузі електроенергетики. Методичні рекомендації до практичних занять з дисципліни для студентів спеціальності 7.030507 «Переклад» напряму підготовки 035 «Філологія»

Методичні матеріали призначено для самостійної роботи студентів спеціальності 7.030507 “Переклад” напряму підготовки 035 «Філологія» для організації практичних занять із дисципліни «Переклад у галузі електроенергетики». Рекомендації орієнтовано на вдосконалення навичок перекладу науково-технічних текстів

Platform Ownership..

We develop a theoretical framework of trade on a platform on which buyers and sellers interact, and compare the impact of different platform ownership structures. If two-sided network effects are strong, monopoly ownership induces more trade than dispersed ownership and is therefore socially preferable. Independent of the strength of network effects, monopoly ownership dominates a club-like ownership structure where incumbent owners can exclude potential entrants. Under dispersed ownership, vertical integration tends to increase welfare as it allows the internalization of demand externalities. Allowing incumbent platform owners to exclude potential entrants hurts buyers but can raise welfare.

Synthesis, physical and chemical properties, and potential applications of graphite fluoride fibers

Graphite fluoride fibers can be produced by fluorinating pristine or intercalated graphite fibers. The higher the degree of graphitization of the fibers, the higher the temperature needed to reach the same degree of fluorination. Pitched based fibers were fluorinated to flourine-to-carbon atom rations between 0 and 1. The graphite fluoride fibers with a fluorine-to-carbon atom ration near 1 have extensive visible structural damage. On the other hand, fluorination of fibers pretreated with bromine or fluorine and bromine result in fibers with a fluorine-to-carbon atom ratio nearly equal to 0.5 with no visible structural damage. The electrical resistivity of the fibers is dependent upon the fluorine to carbon atom ratio and ranged from .01 to 10 to the 11th ohm/cm. The thermal conductivity of these fibers ranged from 5 to 73 W/m-k, which is much larger than the thermal conductivity of glass, which is the regular filler in epoxy composites. If graphite fluoride fibers are used as a filler in epoxy or PTFE, the resulting composite may be a high thermal conductivity material with an electrical resistivity in either the insulator or semiconductor range. The electrically insulating product may provide heat transfer with lower temperature gradients than many current electrical insulators. Potential applications are presented

The contribution of grain boundary barriers to the electrical conductivity of titanium oxide thin films

Titanium oxide thin films were prepared by reactive magnetron sputtering. The reactive gas pulsing process was implemented to control the oxygen injection in the deposition process and,consequently, to tune the oxygen concentration in the films from pure titanium to stoichiometric TiO2, maintaining a homogeneous in-depth concentration. The electrical conductivity of the films was investigated as a function of the oxygen injection time, the metalloid concentration and temperature, in the range 90–600 K. The curved Arrhenius plots of the conductivity were examined taking into account the grain boundary limited transport model of Werner J. H. Werner Solid State Phenom. 37–38, 213 1994 . The grain barrier heights were found to depend significantly on the oxygen supplied into the deposition process and thus, on the oxygen-to-titanium atomic ratio in the films. The analysis as a function of temperature showed that the conduction mechanism in the coatings was not solely limited by the oxygen-to-titanium atomic ratio, but also by the grain boundary scattering

Aptamer Microarrays-Current Status and Future Prospects

Microarray technologies are state of the art in biological research, which requires fast genome, proteome and transcriptome analysis technologies. Often antibodies are applied in protein microarrays as proteomic tools. Since the generation of antibodies against toxic targets or small molecules including organic compounds remains challenging the use of antibodies may be limited in this context. In contrast to this, aptamer microarrays provide alternative techniques to circumvent these limitations. In this article we review the latest developments in aptamer microarray technology. We discuss similarities and differences between DNA and aptamer microarrays and shed light on the post synthesis immobilization of aptamers including corresponding effects on the microarray performance. Finally, we highlight current limitations and future prospects of aptamer microarray technology

Synthese und Strukturen von Bis(amino)germa- und -stanna-Chalkogeniden

Das cyclische Bis(amino)germylen 1 sowie das -stannylen 2 reagieren mit elementarem S, Se oder Te zu Oxidationsprodukten der allgemeinen Formel Me2Si(NtBu)2MEl2M(NtBu)2SiMe2 (M = Ge, El = S (4), El = Se (5), El = Te (6); M = Sn, El = Se (9), El = Te (10)). Nach Röntgenstrukturanalysen (4, 5, 6, 9, 10) bestehen alle Verbindungen aus drei spirocyclisch verbundenen Vierringen SiN2M (2x) und MEl2M, die weitgehend orthogonal zueinander stehen. Die Germanium- und Zinnatome sind folglich verzerrt tetraedrisch koordiniert, während die Chalkogenatome jeweils zwei Nachbaratome unter spitzem Winkel besitzen. Setzt man 1 mit Trimethylamin-N-oxid um, so wird der Sauerstoff an das Germanium übergeben unter Bildung von [Me2Si(NtBu)2GeO]3 (3). Im Gegensatz zu den anderen Verbindungen kann 3 formal als Trimeres aufgefaßt werden: an einem zentralen weitgehend planaren Ge3O3-Sechsring sind spirocyclisch an den Germaniumatomen jeweils drei GeN2Si Vierringe geknüpft (Röntgenstrukturanalyse von 3). In den zentralen Vierringen von 4, 5, 6, 9 und 10 bestehen keine transanularen Wechselwirkungen zwischen den Chalkogenatomen, obwohl diese einen kurzen Abstand untereinander aufweisen. Die gemittelten MEl Abstände betragen: GeO 1,762(5), GeS 2,226(3), GeSe 2,363(3), GeTe 2,592(5), SnSe 2,536(3), SnTe 2,741(3) Å