E-Commerce Infrastructure Success Factors for Small Companies in Developing Economies

This paper looks into the key infrastructure factors affecting the success of small companies in developing economies that are establishing B2B e-commerce ventures. The factors were identified through a literature review and a pilot study carried out in two organizations. The results of the pilot study and literature review reveal five factors that contribute to the success of B2B e-commerce. These factors were later assessed for importance using a survey. The outcome of our analysis reveals that workers' skills, client interface, and technical infrastructure are the most important factors to the success of a B2B e-commerce relationship.     

The effect of cesium content on the thermodynamic stability and chemical durability of (Ba,Cs)1.33(Al,Ti)8O16 hollandite

Titanate-based hollandite ceramics are promising nuclear waste forms for Cs immobilization. In this work, a series of Al-substituted hollandite (Ba_,Cs)_1.33(Al,Ti)₈O₁₆ was investigated across a broad compositional range with varying Cs content. Powder X-ray diffraction showed that all samples exhibited a tetragonal hollandite phase. Enthalpies of formation determined by high-temperature melt solution calorimetry indicated enhanced thermodynamic stability with increased Cs content, which generally agreed with sublattice-based thermodynamic calculations. Moreover, enthalpies of formation of the samples were primarily affected by three factors: (a) relative sizes of cations on the A-sites and B-sites, (b) tolerance factor, and (c) optical basicity. Fractional element release revealed that Cs retention was significantly improved for the high Cs-containing hollandite compositions, which were supported by the evolution of microstructure of the pre and postleach particles. Elution studies of Al-substituted hollandite spiked with radioactive ¹³⁷Cs indicated that transmutation of Cs to Ba in the hollandite was accompanied by an increase in the retention of the Cs decay product, suggesting long-term stability of Al-substituted hollandite phase.     

Recherche d'un béton léger à base de polystyrène expansé facile à mettre en œuvre

Résumé Dans le but d'empêcher la ségrégation des constituants d'un béton léger, à base de ciment, sable et perles de polystyrène expansé, sans recourir à des adhérisants, et d'arriver à effectuer une mise en place par vibration, comme pour le béton hydraulique classique, nous avons employé divers adjuvants. Parmi les produits utilisés, un mélange de 1% (par rapport au poids de ciment) de polyéthylène oxyde et 1% d'un composé de carboxylates et sulfonates métalliques a donné les meilleurs résultats en permettant d'otenir un béton très facile à mettre en place, d'une bonne homogénéité et avec des surfaces lisses grace à une légère couche de laitance de ciment.

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Summary Several admixtures are tested in research on lightweight concrete made with cement, sand and expanded polystyrene beads without incorporating adherence agents, aimed at preventing segregation and promoting placing by vibration as with normal hydraulic concrete. Out of a range of products used the best results are obtained with a 1% mixture (in terms of the weight of cement) of polyethylene oxide and 1% of a compound of carboxylates and metal sulphonates producing easyto-place homogeneous concrete with smooth surfaces formed by a thin layer·of cement laitance.

     

Pulse and Spectrum Manipulation in the Minimum (Frequency) Shift Keying (MSK) Format

The minimum (frequency) shift keying (MSK) format is generalized to enable further improvements in the spectrum while retaining the well-known constant envelope property and the excellent communications efficiency of MSK. A specific alternative to MSK is presented, and the spectrum is compared with that of MSK. The theoretical limitations on possible further spectrum improvements are discussed.     

Simplified MSK Signaling Technique

Modulation and demodulation in the minimum (frequency)-shift keying (MSK) format are reduced to the form of coherent biphase keying. Considerable simplification of circuitry is thus effected without sacrifice of performance. When the ratio of the carrier frequency to the bit rate is high, then the technique described here does not require the precise relative phasing of any pair of oscillators in the transmitter. Experimental results demonstrate the feasibility of synthesizing the one filter that is unique to this signaling scheme. In the present instance, the filter is realized as a surface acoustic wave device.     

Comprehensive numerical simulation of threshold-voltage transients in nitride memories

A new non-local algorithm for accurately calculating the band-to-band tunneling current suitable for TCAD semiconductor simulators is proposed in this paper. The proposed algorithm captures the essential physics of multi-dimensional tunneling in a 2D structure, and is designed to be robust and to achieve independence on the mesh grid. The new algorithm enables accurate modeling of T-FET and investigation of its device physics.     

Some phorbol esters might partially resemble bryostatin 1 in their actions on LNCaP prostate cancer cells and U937 leukemia cells

Phorbol 12‐myristate 13‐acetate (PMA) and bryostatin 1 are both potent protein kinase C (PKC) activators. In LNCaP human prostate cancer cells, PMA induces tumor necrosis factor alpha (TNFα) secretion and inhibits proliferation; bryostatin 1 does not, and indeed blocks the response to PMA. This difference has been attributed to bryostatin 1 not localizing PKCδ to the plasma membrane. Since phorbol ester lipophilicity influences PKCδ localization, we have examined in LNCaP cells a series of phorbol esters and related derivatives spanning some eight logs in lipophilicity (logP) to see if any behave like bryostatin 1. The compounds showed marked differences in their effects on proliferation and TNFα secretion. For example, maximal responses for TNFα secretion relative to PMA ranged from 97 % for octyl‐indolactam V to 24 % for phorbol 12,13‐dibenzoate. Dose–response curves ranged from monophasic for indolactam V to markedly biphasic for sapintoxin D. The divergent patterns of response, however, correlated neither to lipophilicity, to plasma membrane translocation of PKCδ, nor to the ability to interact with model membranes. In U937 human leukemia cells, a second system in which PMA and bryostatin 1 have divergent effects, viz. PMA but not bryostatin 1 inhibits proliferation and induces attachment, all the compounds acted like PMA for proliferation, but several induced a reduced level or a biphasic dose–response curve for attachment. We conclude that active phorbol esters are not all equivalent. Depending on the system, some might partially resemble bryostatin 1 in their behavior; this encourages the concept that bryostatin‐like behavior may be obtained from other structural templates.