The origin of the difference in the superconducting critical temperatures of the beta(H) and beta(L) phases of (BEDT-TTF)(2)I-3

Incommensurate lattice fluctuations are present in the beta(L) phase (T-c similar to 1.5 K) of ET2I3 (where ET is BEDT-TTF - bis(ethylenedithio)tetrathiafulvalene) but are absent in the beta(H) phase (T-c similar to 7 K). We propose that the disorder in the conformational degrees of freedom of the terminal ethylene groups of the ET molecules, which is required to stabilise the lattice fluctuations, increases the quasiparticle scattering rate and that this leads to the observed difference in the Superconducting critical temperatures, T-c, of the two phases. We calculate the dependence of T-c on the interlayer residual resistivity. Our theory has no free parameters. Our predictions are shown to be consistent with experiment. We describe experiments to conclusively test our hypothesis.

Negotiating cross-cultural difference in electronic discussion

Although a good deal of research exists both on computer-mediated communication(CMC) and on cross-cultural communication, rarely are the two areas brought together. In practice, however, extrapolation from one context to the other is common, with the internet and email being increasingly used to teach cross-cultural communication. What assumptions about the transfer of culture into cyberspace inform these practices? And are these assumptions well-founded? This paper explores practices of discussion on French and British internet media sites to determine the extent to which they reflect communicative practices elsewhere in those cultures. The case studies underline the importance of attending to the interaction between culture and genre, and have pedagogical implications for the use of such sites in the teaching of cross-cultural communication.

Crystalloid strong ion difference determines metabolic acid-base change during acute normovolaemic haemodilution

Objective. To study the acid-base effects of crystalloid strong ion difference (SID) during haemodilution. Design. Prospective in vivo study. Setting. University laboratory. Subjects. Anaesthetised, mechanically ventilated Sprague-Dawley rats. Interventions. Rats were studied in seven groups of three. Each group underwent normovolaemic haemodilution with one of seven crystalloids, with SID values from 0 to 40 mEq/l. Six exchanges of 9 ml crystalloid for 3 ml blood were performed. Measurements and main results. [Hb] fell from 142+/-17 to 44+/-10 g/l (p

Differences in mail and telephone responses to self-rated health: use of multiple imputation in correcting for response bias

Objectives: To estimate differences in self-rated health by mode of administration and to assess the value of multiple imputation to make self-rated health comparable for telephone and mail. Methods: In 1996, Survey 1 of the Australian Longitudinal Study on Women's Health was answered by mail. In 1998, 706 and 11,595 mid-age women answered Survey 2 by telephone and mail respectively. Self-rated health was measured by the physical and mental health scores of the SF-36. Mean change in SF-36 scores between Surveys 1 and 2 were compared for telephone and mail respondents to Survey 2, before and after adjustment for socio-demographic and health characteristics. Missing values and SF-36 scores for telephone respondents at Survey 2 were imputed from SF-36 mail responses and telephone and mail responses to socio-demographic and health questions. Results: At Survey 2, self-rated health improved for telephone respondents but not mail respondents. After adjustment, mean changes in physical health and mental health scores remained higher (0.4 and 1.6 respectively) for telephone respondents compared with mail respondents (-1.2 and 0.1 respectively). Multiple imputation yielded adjusted changes in SF-36 scores that were similar for telephone and mail respondents. Conclusions and Implications: The effect of mode of administration on the change in mental health is important given that a difference of two points in SF-36 scores is accepted as clinically meaningful. Health evaluators should be aware of and adjust for the effects of mode of administration on self-rated health. Multiple imputation is one method that may be used to adjust SF-36 scores for mode of administration bias.

Assessing the cellular transmembrane electrical potential difference on the hepatic uptake of palmitate

Understanding the driving forces for the hepatic uptake of endogenous and exogenous substrates in isolated cells and organs is fundamental to describing the underlying hepatic physiology/pharmacology. In this study we investigated whether uptake of plasma protein-bound [H-3]-palmitate across the hepatocyte wall is governed by the transmembrane electrical potential difference (PD). Uptake was studied in isolated hepatocytes and isolated perfused rat livers (IPL). Protein-binding and vasoactive properties of the different perfusates were determined using in vitro heptane/buffer partitioning studies and the multiple indicator dilution (MID) technique in the IPL, respectively. Altering hepatocyte PD by perfusate ion substitution resulted in either a substantial depolarization (-14 +/- 1 mV, n = 12, mean +/- S.E., substituting choline for Na+) or hyperpolarization (-46 +/- 3 mV, n = 12, mean +/- S.E., substituting nitrate for Cl-). Perfusate ion substitution also affected the equilibrium binding constant for the palmitate-albumin complex. IPL studies suggested that, other than with gluconate buffer, hepatic [H-3]-palmitate extraction was not affected by the buffer used, implying PD was not a determinant of extraction. [H-3]-Palmitate extraction was much lower (p < 0.05) when gluconate was substituted for Cl- ion. This work contrasts with that for the extraction of [H-3]-alanine where hepatic extraction fraction was significantly reduced during depolarization. Changing the albumin concentration did not affect hepatocyte PD, and [H-3]-palmitate clearance into isolated hepatocytes was not affected by the buffers used. MID studies with vascular and extravascular references revealed that, with the gluconate substituted buffer, the extravascular volume possibly increased the diffusional path length thus explaining reduced [H-3]-palmitate extraction fraction in the IPL.

Effect on trend estimates of the difference between survey respondents and non-respondents: Results from 27 populations in the WHO MONIICA Project

Introduction: In the World Health Organization (WHO) MONICA (multinational MONItoring of trends and determinants in CArdiovascular disease) Project considerable effort was made to obtain basic data on non-respondents to community based surveys of cardiovascular risk factors. The first purpose of this paper is to examine differences in socio-economic and health profiles among respondents and non-respondents. The second purpose is to investigate the effect of non-response on estimates of trends. Methods:Socio-economic and health profile between respondents and non-respondents in the WHO MONICA Project final survey were compared. The potential effect of non-response on the trend estimates between the initial survey and final survey approximately ten years later was investigated using both MONICA data and hypothetical data. Results: In most of the populations, non-respondents were more likely to be single, less well educated, and had poorer lifestyles and health profiles than respondents. As an example of the consequences, temporal trends in prevalence of daily smokers are shown to be overestimated in most populations if they were based only on data from respondents. Conclusions: The socio-economic and health profiles of respondents and non-respondents differed fairly consistently across 27 populations. Hence, the estimators of population trends based on respondent data are likely to be biased. Declining response rates therefore pose a threat to the accuracy of estimates of risk factor trends in many countries.

An object-oriented designed finite-difference time-domain simulator for electromagnetic analysis and design in MRI - application to high field analyses

This paper presents a finite-difference time-domain (FDTD) simulator for electromagnetic analysis and design applications in MRI. It is intended to be a complete FDTD model of an MRI system including all RF and low-frequency field generating units and electrical models of the patient. The pro-ram has been constructed in an object-oriented framework. The design procedure is detailed and the numerical solver has been verified against analytical solutions for simple cases and also applied to various field calculation problems. In particular, the simulator is demonstrated for inverse RF coil design, optimized source profile generation, and parallel imaging in high-frequency situations. The examples show new developments enabled by the simulator and demonstrate that the proposed FDTD framework can be used to analyze large-scale computational electromagnetic problems in modern MRI engineering. (C) 2004 Elsevier Inc. All rights reserved.

The tempest: Creating dialogue from points of difference

This Article does not have an abstract.

Comparison of cellulose solubilisation rates in rumen and landfill leachate inoculated reactors

The aim of this study was to conduct a number of controlled digestions to obtain easily comparable cellulose solubilisation rates and to compare these rates to those found in the literature to see which operational differences were significant in affecting cellulose degradation during anaerobic digestion. The results suggested that differences in volumetric cellulose solubilisation rates were not indicative of the true performance of cellulose digestion systems. When cellulose solubilisation rates were normalised by the mass of cellulose in the reactor at each time step, the comparison of the rates became more meaningful. Cellulose solubilisation was surface area limited. Therefore, changes in the loading rate of cellulose to the reactor altered the volumetric solubilisation rate without changing the mass normalised rate. Comparison of mass normalised solubilisation rates from this study and the literature demonstrated that differences in reactor configuration and operational conditions did not significantly impact on the solubilisation rate whereas the difference in composition of the microbial communities showed a marked effect. This work highlights the importance of using appropriately normalised data when making comparisons between systems with differing operational conditions. (c) 2005 Elsevier Ltd. All rights reserved.