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Analysis of Competitive and Cooperative Technology Strategies of Electronics Firms in the Greater China Region
This paper integrates several theoretical perspectives to discuss the attributes of successful implementing strategic alliances and supply chain management strategies in high-technology industries. A multiple- case study of Taiwanese and Chinese electronics industries is presented to demonstrate how and why different firms apply different technology strategies in alliances and supply chain formations. Due to intense global competition, technological integration, and product life-cycle time compression, Taiwanese and Chinese high-technology firms are suggested to formulate and implement a coherent technology strategy to enhance their global competitiveness. By applying an integrated framework based on major theoretical perspectives studying the formulation and implementation of competitive and cooperative strategies, the results of this multiple-case study concludes that six closely related strategies, i.e., supply chain positioning, operation efficiency, strategic motives, resource complementarity, organizational learning and capabilities, and strategic flexibility, can be employed by business executives in formulating alliances and supply chain strategies. The research findings serve as an illustration of the multi-dimensionality and complexity of alliance strategies. The framework also provides a useful start to better understanding the dynamic nature of formulating competitive and cooperative technology strategies and to facilitate the effective evaluation of the conditions under these strategies might achieve optimal results
An eleven-vertex deltahedron with hexacapped trigonal bipyramidal geometry.
International audienceThe first elemental cluster with hexacapped trigonal bipyramidal geometry is revealed in the luminescent undecanuclear silver complex which is stabilized by nine dithiocarbamate ligands and has an interstitial hydride. The hydride position within the Ag(11) cage is confirmed by a DFT investigation
Unraveling effects of anti-aging drugs on C. elegans using liposomes
Liposome-mediated delivery is a possible means to overcome several shortcomings with C. elegans as a model for identifying and testing drugs that retard aging. These include confounding interactions between drugs and the nematodes' bacterial food source and failure of drugs to be taken up into nematode tissues. To explore this, we have tested liposome-mediated delivery of a range of fluorescent dyes and drugs in C. elegans. Liposome encapsulation led to enhanced effects on lifespan, requiring smaller quantities of compounds, and enhanced uptake of several dyes into the gut lumen. However, one dye (Texas red) did not cross into nematode tissues, showing that liposomes cannot ensure the uptake of all compounds. Of six compounds previously reported to extend lifespan (vitamin C, N-acetylcysteine, glutathione (GSH), trimethadione, thioflavin T (ThT), and rapamycin), this effect was reproduced for the latter four in a condition-dependent manner. For GSH and ThT, antibiotics abrogated life extension, implying a bacterially mediated effect. With GSH, this was attributable to reduced early death from pharyngeal infection and associated with alterations of mitochondrial morphology in a manner suggesting a possible innate immune training effect. By contrast, ThT itself exhibited antibiotic effects. For rapamycin, significant increases in lifespan were only seen when bacterial proliferation was prevented. These results document the utility and limitations of liposome-mediated drug delivery for C. elegans. They also illustrate how nematode-bacteria interactions can determine the effects of compounds on C. elegans lifespan in a variety of ways
Ferromagnetism in the Hubbard model with orbital degeneracy in infinite dimensions
We study the ferromagnetism due to orbital degeneracy in the Hubbard model in
infinite dimensions. The model contains the intraorbital repulsion , the
interorbital repulsion , the exchange (Hund coupling) and the
pair hopping , where all of them originate from the on-site Coulomb
interaction. The ground state of the effective one-site problem was obtained by
exact diagonalizations. At the 1/4-filling, we found two insulating phases; one
is a ferromagnetic phase with alternating orbital order and the other is
antiferromagnetic one with uniform orbital order. If electrons are doped into
the 1/4-filling, the ferromagnetic phase still survives and becomes metallic,
while the antiferromagnetic phase disappears. This result indicates that the
double-exchange mechanism is relevant to stabilize metallic ferromagnetism in
infinite dimensions.Comment: 4 pages, Revtex, 3 figures, corrected some typos and references, to
be published in Phys. Rev. B (Rapid Communication
Inhibition of SARS-CoV 3C-like Protease Activity by Theaflavin-3,3′-digallate (TF3)
SARS-CoV is the causative agent of severe acute respiratory syndrome (SARS). The virally encoded 3C-like protease (3CL(Pro)) has been presumed critical for the viral replication of SARS-CoV in infected host cells. In this study, we screened a natural product library consisting of 720 compounds for inhibitory activity against 3CL(Pro). Two compounds in the library were found to be inhibitive: tannic acid (IC(50) = 3 µM) and 3-isotheaflavin-3-gallate (TF2B) (IC(50) = 7 µM). These two compounds belong to a group of natural polyphenols found in tea. We further investigated the 3CL(Pro)-inhibitory activity of extracts from several different types of teas, including green tea, oolong tea, Puer tea and black tea. Our results indicated that extracts from Puer and black tea were more potent than that from green or oolong teas in their inhibitory activities against 3CL(Pro). Several other known compositions in teas were also evaluated for their activities in inhibiting 3CL(Pro). We found that caffeine, (—)-epigallocatechin gallte (EGCg), epicatechin (EC), theophylline (TP), catechin (C), epicatechin gallate (ECg) and epigallocatechin (EGC) did not inhibit 3CL(Pro) activity. Only theaflavin-3,3′-digallate (TF3) was found to be a 3CL(Pro) inhibitor. This study has resulted in the identification of new compounds that are effective 3CL(Pro) inhibitors
Origin of Spin Incommensurability in Hole-doped S=1 Chains
Spin incommensurability has been recently experimentally discovered in the
hole-doped Ni-oxide chain compound (G. Xu {\it
al.}, Science {\bf 289}, 419 (2000)). Here a two orbital model for this
material is studied using computational techniques. Spin IC is observed in a
wide range of densities and couplings. The phenomenon originates in
antiferromagnetic correlations ``across holes'' dynamically generated to
improve hole movement, as it occurs in the one-dimensional Hubbard model and in
recent studies of the two-dimensional extended t-J model. The close proximity
of ferromagnetic and phase-separated states in parameter space are also
discussed.Comment: RevTex, 4 pages, 4 figures (eps
Metallic ferromagnetism: Progress in our understanding of an old strong-coupling problem
Metallic ferromagnetism is in general an intermediate to strong coupling
phenomenon. Since there do not exist systematic analytic methods to investigate
such types of problems, the microscopic origin of metallic ferromagnetism is
still not sufficiently understood. However, during the last two or three years
remarkable progress was made in this field: It is now certain that even in the
one-band Hubbard model metallic ferromagnetism is stable in dimensions
2, and on regular lattices and at intermediate values of the
interaction and density . In this paper the basic questions and recent
insights regarding the microscopic conditions favoring metallic ferromagnetism
in this model are reviewed. These findings are contrasted with the results for
the orbitally degenerate case.Comment: 16 pages, 13 figures, latex using vieweg.sty (enclosed); typos
corrected; to appear in "Advances in Solid State Physics", Vol. 3
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