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Schistosomes are long-lived blood dwelling helminth parasites using intricate mechanisms to invade, mature, and reproduce inside their vertebrate hosts, whilst simultaneously deploying immune evasion strategies. Their multi-tissue organization and solid body plan presents particular problems for the definition of sub-proteomes.Here, we focus on the two host-parasite interfaces of the adult worm accessible to the immune system, namely the tegument and the alimentary tract, but also on the secretions of the infective cercaria, the migrating schistosomulum and the mature egg. In parallel, we introduce the concepts of "leakyome' and 'disintegrome' to emphasize the importance of interpreting data in the context of schistosome biology so that misleading conclusions about the distinct proteome compositions are avoided. Lastly, we highlight the possible clinical implications of the reviewed proteomic findings for pathogenesis, vaccine design and diagnostics.Proteomics has provided considerable insights into the biology of schistosomes, most importantly for rational selection of novel vaccine candidates that might confer protective immunity, but also into the pathogenesis of schistosomiasis. However, given the increasing sensitivity of mass spectrometric instrumentation, we stress the need for care in data interpretation since schistosomes do not deviate from the fundamental rules of eukaryotic cell biology.

1. In this manuscript we describe a non-radioactive, high-throughput method to evaluate hepatic uptake using cryopreserved hepatocytes. We have validated the uptake of pravastatin with different amounts of hepatocytes and the impact of the oil layer used in separation. The time- and concentration-dependent uptake profiles of several anionic and cationic charged drugs were evaluated. The results with our method compare favourably with the literature for pravastatin, atorvastatin and estrone 3-sulfate. 2. Two approaches for kinetic determination (temperature difference and fitting the linear and non-saturable passive diffusion rate in the equation, i.e. V = (V(max) × S)/(K(m) + S) + P(dif) × S) have been evaluated. Kinetic studies indicate that the different approaches for determining passive diffusion can affect K(m) and V(max), but not the clearance of active uptake (V(max)/K(m)). 3. Using pravastatin as a probe substrate, species differences were observed in the organic anion-transporting polypeptide (OATP) 1B1 and 1B3 activities. Plasma protein significantly reduced the uptake of atorvastatin, but not pravastatin. 4. Our data suggests that evaluation of the role of active uptake in hepatic clearance in humans should consider the relative ratio of active uptake to passive diffusion, species differences and plasma protein binding when applying in vitro uptake data.

This article explores the nature, antecedents and consequences of a potential service orientation discrepancy in a UK public sector setting. The quantitative and qualitative data collected suggest that: (1) similar to the private sector, employees perceive a discrepancy between their own service orientation and that of the organisation; (2) the antecedents for this discrepancy differ from the private sector: employees' commitment to help communities contrasts with Modernising Government efforts to drive efficiency while neglecting effectiveness; (3) emphasising the development of tailored and proactive services may reduce the service orientation discrepancy and thus improve service performance and job satisfaction.

The aim of this paper is to establish a creative link between contemporary remote sensing and urban analysis. The argument is rooted in model-based urban analysis and it is shown that, mainly through spatial interaction modelling, the workings of the city-the 'physiology'-can be represented. Models have now been extended to have the capacity to represent structural dynamics and this is shown to be dependent on what can be characterized as 'urban DNA'. It is shown that urban information systems can be enhanced by remote sensing, particularly temporally, through the concept of an intelligent information warehouse (IIW) and that such a system relates to 'urban DNA' structure in the same way as X-ray crystallography relates to the elucidation of DNA. This adds to the potential capability of analysing, even predicting, urban phase transitions as an aid to planning.

2-Acetyl-4(5)-tetrahydroxybutyl imidazole (THI) has been shown to reduce rodent peripheral blood lymphocytes through increasing lymphoid sphingosine 1-phosphate (S1P) by inhibiting S1P lyase. The objective of this study was to characterize the relationship between systemic THI exposure, splenic S1P concentrations, and lymphopenia in rats. Following the oral administration of 10 and 100 mg kg(-1) THI to male rats, THI was rapidly absorbed and reached a plasma peak level at 1 h post-dosing. Splenic S1P increased and reached the peak level at 24 h. Blood lymphocyte count decreased as the splenic S1P level increased. THI plasma concentration was linked to splenic S1P concentration using an indirect model incorporated with a four-step signal transduction model. In turn, the S1P level was directly coupled with blood lymphocyte number. The integrated model simultaneously captured the splenic S1P and blood lymphocyte responses. This pharmacokinetic-biomarker-pharmacodynamic model resolved the remarkable discrepancy between plasma THI concentration and the pharmacological response and quantitatively described the relationship of THI exposure, S1P, and lymphopenic response.

This article looks at the surge of interest from marketing scholars and organizational behaviourists in two distinct but inextricably linked areas - corporate identity and organizational identity.

This paper looks at domination, self-validation, narcissistic deprivation, instrumental anger and negative selves in relation to the desire to control others. Three case studies are presented and analysed to determine alternative explanations of the need and desire to control others. The therapist investigates the client's early experiences with control to find meaningful connections with current behaviours and past events.

Samples of nanocrystalline Cu doped ZnO have been prepared and characterised by several techniques including chemical analysis, X-ray powder diffraction and X-Ray absorption spectra (EXAFS). The particle sizes are typically less than 100 A on the largest diameter. The diffraction results show that lightly doped samples, less than 10 mole per cent Cu, are single phase with the ZnO crystal structure. The EXAFS results indicate that although the Zn2+ ions occupy normal cation sites the Cu2+ ions are in highly disordered sites, suggesting that there is possible surface aggregation. Gas sensing experiments show a good response to low ppm concentrations of toluene vapour.

This article considers the major emphasis currently being placed by the retail banks on the distribution element of the marketing mix. In particular, it demonstrates that the retail banks within the UK have recognised the importance of the branch network in achieving a competitive advantage and are currently active to a greater or lesser degree in adopting a retail-oriented marketing mix for bank branch operations. The article goes on to argue that the mix has not yet been successfully co-ordinated as a result of the limited remit of marketing personnel within the banking sector.

This paper summarises recent progress in understanding the processes which lead to large increases in the semiconductivity of metal phthalocyanine films in the presence of even very small (sub-ppm) concentrations of nitrogen dioxide. A model, based on experimental data, for the kinetics of the adsorption process is described and its application in a microprocessor-controlled NO2-sensing instrument is outlined. Chemical and morphological modification of the surfaces of lead phthalocyanine films by heat-treatment at 360° C in air is shown to lead to smaller but faster responses to NO2 and possible origins of these effects are discussed with reference to data from electron microscopy, XPS and FTIR spectroscopy. Measurements of the strength of gas-surface interactions using a novel fibre-optic interferometric calorimeter are discussed with reference to the above data, and suggest that adsorption of NO2 does not lead immediately to charge-carrier generation.

Alan Wilson reviews Marketing Strategies for Services edited by Michel Kostecki (Pergamon Press, 1994) £37.00. ISBN 0 08 042389 2

The mathematical topics which are of use to geography students are outlined, as are the methods used for teaching mathematical techniques in geography courses at Leeds over the last few years. The concluding section relates practice to goals, and the problems of providing the student with a framework into which he can fit all the pieces of knowledge he has acquired. Possible future developments are reviewed briefly in the light of the development of new mathematical techniques on the one hand, and criticisms of the existing state of the art on the other. The subject matter of the paper is limited to mathematical education, and there is only indirect and brief concern with statistics.

Coelho J. D. and Wilson A. G. (1976) The optimum location and size of shopping centres, Reg. Studies 10, 413–421. An optimisation criterion is presented for the size and siting of shopping centres (using the maximisation of consumers' surplus) and this is integrated with a spatial interaction model of shopping trip behaviour. It is shown how the consumers' surplus can be maximised subject to the interaction model equations as constraints within a non-linear programming framework. The problem can be transformed to one which has a log linear objective function to linear constraints and so can be solved by standard methods. Disaggregated versions of the problem are explored together with the relationship to location-allocation problems and the hierarchy of centres in central place theory.

Rees P. H. and Wilson A. G. (1974) A comparison of available models of population change, Reg. Studies 9, 39–61. A hypothetical example and a common algebraic notation are employed in this paper to facilitate a systematic comparison of available models of population growth processes. The models reviewed are the cohort survival model (in “closed system” Leslie form, single region/components form, and in Rogers' multi-regional form), a projection model based on a multiregional life table, Stone's demographic accounting model and the account-based model of the present authors. Some concluding comments are made which offer indicators of how the “effectiveness” of the models can be assessed by potential users.

Wilson A. G., Hawkins A. F., Hill G. J. and Wagon D. J. (1969) Calibrating and testing of the SELNEC transport model, Reg. Studies 3, 337–350. This paper describes the mathematical model used in the South-East Lancashire-North-East Cheshire Transportation Study. The description concentrates on the innovations which have been introduced in this particular model, with special reference to the distribution and modal split submodels. The process of calibrating and testing the model is described and some preliminary results are presented. A number of conclusions are drawn, and some directions for further research are noted.