Upper-Bound Performance of Radial Basis Function Decision Feedback Equalised Burst-by-Burst Adaptive Modulation

The upper-bound performance of radial basis function decision feedback equalised (RBF DFE) burst-by-burst adaptive modulation is presented for tranmissions over dispersive wideband mobile channels. The RBF DFE is capable of estimating the 'short term bit error rate' of the received data burst and this estimate is used as the modem mode switching criterion in order to switch between different modulation schemes. The performance of this scheme and that of the individual fixed modulation schemes is compared, demonstrating a significant mean bit error rate (BER) and bits per second (BPS) performance improvement

Amiodarone-induced Hypothyroidism with EPO-resistant Anemia in a Patient with Chronic Renal Failure

The overall incidence of amiodarone-induced thyroid dysfunction ranges from 2% to 24%. One third to half of patients with hypothyroidism have anemia due to some decrease in normal red blood cell mass and erythropoietin (EPO) resistance. Therefore, for patients with chronic renal disease under medication with amiodarone, early regular thyroid function test should be checked in order to avoid amiodarone-induced hypothyroidism and EPO-resistant anemia. If amiodarone-induced hypothyroidism and EPO-resistant anemia occur in patients with chronic renal failure, early thyroxine should be given instead of waiting for spontaneous recovery by amiodarone discontinuation only. Here, we report a patient with chronic renal failure who developed EPO-resistant anemia after amiodarone treatment for arrhythmia. The hemoglobin level responded to EPO therapy rapidly after thyroxine administration and amiodarone discontinuation

Determinants of negative word-of-mouth communication using social networking sites

At present, as customers often turn to social media platforms to share their service experience, this study aims to examine the determinants of their negative word-of-mouth communication using social networking sites following a service failure. Although many studies have examined the electronic word-of-mouth communication, studies on negative word-of-mouth communication using social media platforms remain sparse. Building on the cognitive dissonance theory and social support theory, this study proposes and empirically examines the role of contextual, individual and social networking factors in determining the customers’ intentions to engage in negative word-of-mouth communication using social networking sites. Self-reported retrospective survey was used to obtain responses from 206 online shoppers. The results of the structural equation modelling showed that feeling of injustice, firm attribution, firm image, face concern, reappraisal, use intensity and tie strength are key antecedents of negative word-of-mouth communication. The findings provide valuable insights for managers in developing effective Webcare interventions for negative word-of-mouth communication on social networking sites

OBJECTIVE AND SUBJECTIVE KNOWLEDGE: IMPACTS ON CONSUMER DEMAND FOR GENETICALLY MODIFIED FOODS IN THE UNITED STATES AND THE EUROPEAN UNION

In the growing body of literature on consumer acceptance of genetically modified (GM) foods, there are significant differences on the impact of knowledge on acceptance of GM foods. One potential explanation is the manner in which knowledge is measured. The goal of this study is to differentiate and examine the impact of both subjective and objective knowledge related to acceptance of genetically modified foods. Data from surveys collected in the United States, England, and France is used.Research and Development/Tech Change/Emerging Technologies,

Nonlinear force-free magnetic field extrapolations: comparison of the Grad-Rubin and Wheatland-Sturrock-Roumeliotis algorithm

We compare the performance of two alternative algorithms which aim to construct a force-free magnetic field given suitable boundary conditions. For this comparison, we have implemented both algorithms on the same finite element grid which uses Whitney forms to describe the fields within the grid cells. The additional use of conjugate gradient and multigrid iterations result in quite effective codes. The Grad-Rubin and Wheatland-Sturrock-Roumeliotis algorithms both perform well for the reconstruction of a known analytic force-free field. For more arbitrary boundary conditions the Wheatland-Sturrock-Roumeliotis approach has some difficulties because it requires overdetermined boundary information which may include inconsistencies. The Grad-Rubin code on the other hand loses convergence for strong current densities. For the example we have investigated, however, the maximum possible current density seems to be not far from the limit beyond which a force free field cannot exist anymore for a given normal magnetic field intensity on the boundary.Comment: 21 pages, 13 figure

Action principle formulation for motion of extended bodies in General Relativity

We present an action principle formulation for the study of motion of an extended body in General Relativity in the limit of weak gravitational field. This gives the classical equations of motion for multipole moments of arbitrary order coupling to the gravitational field. In particular, a new force due to the octupole moment is obtained. The action also yields the gravitationally induced phase shifts in quantum interference experiments due to the coupling of all multipole moments.Comment: Revised version derives Octupole moment force. Some clarifications and a reference added. To appear in Phys. Rev.

Observational Constraints on Chaplygin Quartessence: Background Results

We derive the constraints set by several experiments on the quartessence Chaplygin model (QCM). In this scenario, a single fluid component drives the Universe from a nonrelativistic matter-dominated phase to an accelerated expansion phase behaving, first, like dark matter and in a more recent epoch like dark energy. We consider current data from SNIa experiments, statistics of gravitational lensing, FR IIb radio galaxies, and x-ray gas mass fraction in galaxy clusters. We investigate the constraints from this data set on flat Chaplygin quartessence cosmologies. The observables considered here are dependent essentially on the background geometry, and not on the specific form of the QCM fluctuations. We obtain the confidence region on the two parameters of the model from a combined analysis of all the above tests. We find that the best-fit occurs close to the $\Lambda$CDM limit ($\alpha=0$). The standard Chaplygin quartessence ($\alpha=1$) is also allowed by the data, but only at the $\sim2\sigma$ level.Comment: Replaced to match the published version, references update