An iterative ADI-FDTD with reduced splitting error

We present a new iterative alternating-direction-implicit finite-difference time-domain (ADI-FDTD) method. By recognizing the ADI-FDTD method as a special case of a more general iterative approach to solve the Crank-Nicolson (CN) FDTD scheme, the splitting error in ADI-FDTD can be reduced systematically. Numerical examples are used to illustrate the improved accuracy of this method.     

Experimental evaluation of capacity statistics for short VDSL loops

We assess the capacity potential of very short very-high data-rate digital subscriber line loops using full-binder channel measurements collected by France Telecom R&D. Key statistics are provided for both uncoordinated and vectored systems employing coordinated transmitters and coordinated receivers. The vectoring benefit is evaluated under the assumption of transmit precompensation for the elimination of self-far-end crosstalk, and echo cancellation of self-near-end crosstalk. The results provide useful bounds for developers and providers alike.     

Patients' preferences for pain treatment modalities in a multidisciplinary pain clinic.

44 male and 74 female patients (aged 22–78 yrs) in a multidisciplinary pain clinic rated their preferences for 9 pain treatment modalities: ice, transcutaneous electronic nerve stimulation (TENS), relaxation, group therapy, social work, physical therapy, massage, heat, and lectures. Relaxation, physical therapy, and ice were most liked; TENS, heat, and social work were least liked. Multiple regression analyses indicated that preference for relaxation was the best predictor of decreased pain ratings, while preference for heat was correlated with increased pain ratings. Liking for physical therapy predicted self-ratings at discharge of positive well-being and minor life disruption. Liking for heat predicted self-ratings of major life disruption and nurses' ratings of pain behavior at discharge. Results suggest that treatment regimens should take into account patients' moods and personality styles. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Future increase in harmful algal blooms in the North Sea due to climate change.

In temperate seas such as the North Sea harmful (toxic) algal blooms will probably increase as a result of climate change. This conclusion was reached after investigating the projected effect of climate change for the year 2100 in Dutch coastal waters (4 degrees C temperature rise and increased water column stratification) on the growth rates of six harmful and two non-harmful phytoplankton species. Micro algae form the basis of the marine food chain. However, toxin-producing species may seriously disrupt the food web and lead to fish kills and human intoxication. Two species with estimated doubled growth rates in 2100, F. japonica and C. antiqua, entered Europe via ship's ballast water or shellfish imports. This stresses the need to legally regulate such invasion routes in order to prevent the import of novel species. Future toxic phytoplankton blooms may further devaluate ecosystem deliverables such as fish production or recreational use. This devaluation can be estimated by monetary value assessments that are needed in cost-benefit analyses for policy guidance. The lack of understanding of future climate, ecosystem functioning and its response to climate change calls for a scientific effort to improve our knowledge on present day coastal ecosystem functioning and its resilience.     

Determination of the relative amounts of free and complexed manganese ions in aqueous solution by nuclear magnetic resonance.

The ratio of the transverse relaxation rate to the longitudinal relaxation rate of water protons (T1/T2) at 90 MHz can be used to determine the relative amounts of free Mn2+ ions (the hexaquo ion) and chelated manganese ions when both species are present in the same aqueous solution. This technique is demonstrated for simple aqueous solutions containing known concentrations of both the free Mn2+ ion and a manganese(III) porphyrin. The accuracy of the method is found to be +/- 7.3% for the solutions considered in this report. The determinations of the relative amounts of the free Mn2+ ion and the manganese(III) porphyrin by this T1/T2 method are shown to agree well with those determined by nuclear magnetic resonance dispersion profiles. The theoretical basis of this ratio method as well as the scope and limitations in its application to aqueous solutions containing both free Mn2+ ions and chelated manganese species other than manganese(III) porphyrins are also discussed. This work demonstrates a unique use of NMR as a means for the quantitative analysis of manganese in which the effects of the metal ion on the solvent, and not the metal itself, are observed.