A modeling approach on the TelosB WSN platform power consumption

Substantial characteristics of wireless sensor networks, such as autonomy and miniature size, are achieved at the expense of restricted energy resources. Optimal resource management is thus among the most important challenges in WSNs development and its success requires accurate and practical models based on detailed insight concerning the factors contributing to the overall power consumption of a WSN mote. To achieve such awareness, that will enable models development, appropriate measuring test-beds and methodologies are needed, facilitating reliable and accurate power consumption measurements of critical functionalities.To cover the need for energy models that precisely define the power consumption behavior of WSN hardware platforms, this paper contributes with a measuring methodology including three steps: the design and implementation of a measuring system for a wide range of power consumption thresholds, the identification, isolation and measurement of elementary functionalities of a WSN platform with respect to their contribution to the overall mote power consumption, and the extraction of valuable conclusions based on the respective measurements resulting in the composition of a practical, yet accurate power consumption model.     

The Embedding of Transnational Entrepreneurs in Diaspora Networks: Leveraging the Assets of Foreignness

In this paper we examine how foreign actors capitalize on their ethnic identity to gain skills and capabilities that enable them to operate in a new and strange environment. We explore the mechanisms by which Bulgarian entrepreneurs in London use their ethnic identity to develop competitive advantage and business contacts. We find that the entrepreneurs studied gain access to a diaspora network, which enables them to develop essential business capabilities and integrate knowledge from both home and host country environments. The diaspora community possesses a collective asset (transactive memory) that allows its members to remove competition from the interfirm level to the network level (i.e., diaspora networks vs. networks of native businesspeople). Additionally, the cultural identity and networks to which community members have access provide bridging capabilities that allow diaspora businesspeople to make links to host country business partners and thus embed themselves in the host country environment. Thus, this paper adds to the growing body of work showing how foreignness can serve as an asset in addition to its better-known role as a liability.     

Quantification of phosphorus metabolites from chemical shift imaging spectra with corrections for point spread effects and B1 inhomogeneity

Neospora caninum is an apicomplexan parasite which is morphologically and ultrastructurally very similar to Toxoplasma gondii. In order to identify molecules involved in host cell entry and subsequent modification of the parasitophorous vacuole, a polyclonal antiserum directed against N. caninum tachyzoites was raised in a rabbit. Subcellular fractionation of tachyzoites was performed using the non-ionic detergent Triton-X-114. Membrane fractions were analysed by immunoblotting using the polyclonal antiserum. One of the immunoreactive protein bands had a mol. wt of 33,000 and was subsequently named Nc-p33. Affinity-purified anti-Nc-p33 antibodies were used to characterise this polypeptide using SDS-PAGE, isoelectric focusing, Western blot analysis and immuno-EM. Nc-p33 was found in two isolates of N. caninum (NC-1 and Liverpool), but could not be detected in T. gondii tachyzoites. Immunogold EM revealed that Nc-p33 constituted a dense granule-associated protein, and Western blotting demonstrated that Nc-p33 was most likely identical to the recently described antigen NCDG1. Shortly after invasion, this dense granule protein was targeted to the parasitophorous vacuole membrane, and, at later timepoints after infection, was also found on the parasitophorous vacuolar network. This suggested that Nc-p33 could play a functional role in the modification of the parasitophorous vacuole and its membrane.     

Sample classification based on Bayesian spectral decomposition of metabonomic NMR data sets

1H NMR spectra of biofluids provides a wealth of biochemical information on the metabolic status of an organism. Through the application of pattern recognition and classification algorithms, the data have been shown to provide information on disease diagnosis and the beneficial and adverse effects of potential therapeutics. Here, a novel approach is described for identifying subsets of spectral patterns in databases of NMR spectra, and it is shown that the intensities of these spectral patterns can be related to the onset and recovery from a toxic lesion in both a time-related and dose-related fashion. These patterns form a new type of combination biomarker for the biological effect under study. The approach is illustrated with a study of liver toxicity in rats using NMR spectra of urine following administration of a model hepatotoxin hydrazine.     

Spatio-temporal carrier dynamics in ultrashort-pulse laser irradiated materials

A space and time-dependent quantum-kinetic theory has been formulated based on previous theoretical approaches to study the spatio-temporal microscopic carrier dynamics in laser excited semiconductor materials that accounts for the effects of inhomogeneous excitation and structural inhomogeneities due to bulk filamentation damage and micro/nano structuring. The approach involves extensive computational effort.     

Catalytic activity of Fe/AC, obtained by impregnation of activated carbon in aqueous and non-aqueous media, to neutralize NO

The influence of the nature of the impregnating solutions media (aqueous or non-aqueous) on the forming of active phases is investigated in case of preparing iron catalysts, supported on activated carbon with respect to their catalytic activity in the reaction of NO reduction by CO. The catalysts are characterized by chemical analysis (AAS), BET surface area, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), magnetic susceptibility, and Mössbauer spectroscopy (MS). The catalytic investigations and TPD are carried out in a flow apparatus. Three peculiarities are observed with respect to this influence—the ratio between the separate iron species in different oxidation state of Fe species, which build up the catalytic active complexes (CAC), common participation of superficial groups of the carbon support and Fe components of the impregnating solutions as well as different dispersion of the active phase on the surface of the samples. As a result the highest catalytic activity was observed with the sample, obtained by impregnation with an aqueous solution, while with the other samples, obtained from organic solutions, the catalytic activity decreases in the order of: Methanol > Ethyl Ether > Acetone. It was assumed that the different catalytic activities are connected most probably with the process of forming of CAC during the process of preparation of the samples.     

Effect of the molecular structure of some quinones on their corrosion inhibiting action

The molecular characteristics obtained by quantum chemical self‐consistent field (SCF) calculations of a series of quinones are correlated with the experimentally determined inhibitor efficiency for mild steel corrosion in neutral aqueous medium. It was established that the decrease of the ionization potential and the increase of the dipole moment of the quinone molecules favor the higher protective effect. The electron density and the geometric molecular structure have also been computed and are discussed in view of the corrosion inhibition.