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The results from a mail survey with 300 copies of a self-administrated questionnaire utilising the SERVQUAL instrument to provide a unique analysis of service quality, value, customer satisfaction and loyalty of Singapore stock investors. The study provides practical advice for brokers and other financial service providers, particularly in the light of emerging credence service and commercial friends concepts in the financial services sector.

This paper presents an experimental investigation of the Uniform Expected Utility (UEU) criterion, a model for ranking sets of uncertain outcomes. We verified whether the two behavioral axioms characterizing UEU, i.e., Averaging and Restricted Independence, are satisfied in a pairwise choice experiment with monetary gains. Our results show that neither of these axioms holds in general. Averaging in particular, appears to be violated on a large scale. On the basis of the current study and a previous one, we can conclude that none of the models for set ranking that have been axiomatically characterized so far is able to model observed choices between sets of possible outcomes in a satisfactory fashion. In this paper we therefore lay out the foundations for a new descriptive model for set ranking: the Uniform Rank-Dependent Utility (URDU) criterion. [ABSTRACT FROM AUTHOR]

In image guided radiotherapy (IGRT) two of the most promising recent developments are four dimensional cone beam CT (4D CBCT) and dynamic optical metrology of patient surfaces. 4D CBCT is now becoming commercially available and finds use in treatment planning and verification, and whilst optical monitoring is a young technology, its ability to measure during treatment delivery without dose consequences has led to its uptake in many institutes. In this paper, we demonstrate the use of dynamic patient surfaces, simultaneously captured during CBCT acquisition using an optical sensor, to phase sort projection images for 4D CBCT volume reconstruction. The dual modality approach we describe means that in addition to 4D volumetric data, the system provides correlated wide field measurements of the patient's skin surface with high spatial and temporal resolution. As well as the value of such complementary data in verification and motion analysis studies, it introduces flexibility into the acquisition of the signal required for phase sorting. The specific technique used may be varied according to individual patient circumstances and the imaging target. We give details of three different methods of obtaining a suitable signal from the optical surfaces: simply following the motion of triangulation spots used to calibrate the surfaces' absolute height; monitoring the surface height in a single, arbitrarily selected, camera pixel; and tracking, in three dimensions, the movement of a surface feature. In addition to describing the system and methodology, we present initial results from a case study oesophageal cancer patient.

Abstract: Suppose that a binary relation is given on a -fold Cartesian product. The study of the conditions guaranteeing the existence of value functions such that the binary relation can be additively represented is known as additive conjoint measurement. In this paper we analyze a related problem: given a partition of a Cartesian product into ordered categories, what conditions do ensure the representability of the partition in an additive model? [Copyright &y& Elsevier]

Cone beam CT (CBCT) using a zonal filter is introduced. The aims are reduced concomitant imaging dose to the patient, simultaneous control of body scatter for improved image quality in the tumour target zone and preserved set-up detail for radiotherapy. Aluminium transmission diaphragms added to the CBCT x-ray tube of the Elekta Synergy™ linear accelerator produced an unattenuated beam for a central ‘target zone’ and a partially attenuated beam for an outer ‘set-up zone’. Imaging doses and contrast noise ratios (CNR) were measured in a test phantom for transmission diaphragms 12 and 24 mm thick, for 5 and 10 cm long target zones. The effect on automatic registration of zonal CBCT to conventional CT was assessed relative to full-field and lead-collimated images of an anthropomorphic phantom. Doses along the axis of rotation were reduced by up to 50% in both target and set-up zones, and weighted dose (two thirds surface dose plus one third central dose) was reduced by 10–20% for a 10 cm long target zone. CNR increased by up to 15% in zonally filtered CBCT images compared to full-field images. Automatic image registration remained as robust as that with full-field images and was superior to CBCT coned down using lead-collimation. Zonal CBCT significantly reduces imaging dose and is expected to benefit radiotherapy through improved target contrast, required to assess target coverage, and wide-field edge detail, needed for robust automatic measurement of patient set-up error.

The problem of heat and mass transfer within a porous catalytic pellet in which an irreversible first–order exothermic reaction occurs is a much–studied problem in chemical–reactor engineering. The system is described by two coupled reaction–diffusion equations for the temperature and the degree of reactant conversion. The Galerkin method is used to obtain a semi–analytical model for the pellet problem with both one– and two–dimensional slab geometries. This involves approximating the spatial structure of the temperature and reactant–conversion profiles in the pellet using trial functions. The semi–analytical model is obtained by averaging the governing partial differential equations. As the Arrhenius law cannot be integrated explicitly, the semi–analytical model is given by a system of integrodifferential equations. The semi–analytical model allows both steady–state temperature and conversion profiles and steady–state diagrams to be obtained as the solution to sets of transcendental equations (the integrals are evaluated using quadrature rules). Both the static and dynamic multiplicity of the semi–analytical model is investigated using singularity theory and a local stability analysis. An example of a stable limit cycle is also considered in detail. Comparison with numerical solutions of the governing reaction–diffusion equations and with other results in the literature shows that the semi–analytical solutions are extremely accurate.

The Gray–Scott model of cubic–autocatalysis with linear decay is coupled with diffusion and considered in a one–dimensional reactor (a reaction–diffusion cell). The boundaries of the reactor are permeable, so diffusion occurs from external reservoirs that contain fixed concentrations of the reactant and catalyst. The Galerkin method is used to approximate the spatial structure of the reactant and autocatalyst concentrations in the reactor. Ordinary differential equations are then obtained as an approximation to the governing partial differential equations. The ordinary differential equations are then analysed to obtain semi–analytical results for the reaction–diffusion cell. Steady–state concentration profiles and bifurcation diagrams are obtained both explicitly, for the one–term method, and as the solution to a pair of transcendental equations, for the two–term method. Singularity theory is used to determine the regions of parameter space in which the four main types of bifurcation diagram occur. Also, in the semi–analytical model, a fifth bifurcation diagram occurs in an extremely small parameter region; its size being O(10–10). The region of parameter space, in which Hopf bifurcations can occur, is found by a local stability analysis of the semi–analytical model. An example of a stable limitcycle is also considered in detail. The usefulness and accuracy of the semi–analytical results are confirmed by comparison with numerical solutions of the governing partial differential equations.

The initial boundary–value problem for the Korteweg–de Vries (KdV) equation on the negative quarter–plane, x < 0 and t > 0, is considered. The formulation of this problem is different to the usual initial boundary–value problem on the positive quarter–plane, for which x > 0 and t > 0. Two boundary conditions are required at x 0 for the negative quarter–plane problem, in contrast to the one boundary condition needed at x 0 for the positive quarter–plane problem. Solutions of the KdV equation on the infinite line, such as the soliton, cnoidal wave, mean height variation and undular bore solution, are used to find approximate solutions to the negative quarter–plane problem. Five qualitatively different types of solution are found, depending on the relation between the initial and boundary values. Excellent comparisons are obtained between these solutions and full numerical solutions of the KdV equation.

Solitary wave interaction is examined, for the case of surface waves on shallow water, by using an extended Benjamin–Bona–Mahony (eBBM) equation. This equation includes higher–order nonlinear and dispersive effects, and hence is asymptotically equivalent to the extended Korteweg–de Vries (eKdV) equation. However, it has certain numerical advantages as it allows the modelling of steeper waves, which, due to numerical instability, is not possible using the eKdV equation.Numerical simulations of a number of collisions of varying nonlinearity are performed. The numerical results show evidence of inelastic behaviour at high order. For waves of small amplitude the evidence of inelastic behaviour is indirect; after collision a dispersive wavetrain of extremely small amplitude is found behind the smaller solitary wave. For steeper waves, however, direct evidence of inelastic behaviour is found; the larger wave is increased and the smaller wave is decreased in amplitude after the collision.Conservation laws for the mass and energy, exact and asymptotic, respectively, are derived for the eBBM equation, and numerically verified. Data from the collisions, such as the change in solitary wave amplitudes, the higher–order phase shifts and the mass and energy of the dispersive wavetrains are all tabulated. These are used to show that the change in solitary wave amplitude is of O(α4), verifying previously obtained theoretical predictions. A good comparison is also obtained between the numerically obtained phase shifts and existing asymptotic results.Lastly, three different eBBM solitary wave interactions are examined in detail and compared with existing numerical data obtained from alternative weakly nonlinear models and the Euler water–wave equations.

We present a large-scale social marketing programme of insecticide-treated nets in 2 rural districts in south-western Tanzania (population 350 000) and describe how the long-term child health and survival impact will be assessed. Formative and market research were conducted in order to understand community perceptions, knowledge, attitudes and practice with respect to the products to be socially marketed. We identified Zuia Mbu(Kiswahili for ‘prevent mosquitoes’) as a suitable brand name for both treated nets and single-dose insecticide treatment sachets. A mix of public and private sales outlets is used for distribution. In the first stage of a stepped introduction 31 net agents were appointed and trained in 18 villages: 15 were shop owners, 14 were village leaders, 1 was a parish priest and 1 a health worker. For net treatment 37 young people were appointed in the same villages and trained as agents. Further institutions in both districts such as hospitals, development projects and employers were also involved in distribution. Promotion for both products was intense and used a variety of channels. A total of 22 410 nets and 8072 treatments were sold during the first year: 18 months after launching, 46% of 312 families with children aged under 5 years reported that their children were sleeping under treated nets. A strong evaluation component in over 50 000 people allows assessment of the long-term effects of insecticide-treated nets on child health and survival, anaemia in pregnancy, and the costs of the intervention. This evaluation is based on cross-sectional surveys, and case-control and cohort studies.

The steady-state microwave heating of a finite one-dimensional slab is examined. The temperature dependency of the electrical conductivity and the thermal absorptivity is assumed to be governed by the Arrhenius law, while both the electrical permittivity and magnetic permeability are assumed constant. The governing equations are the steady-state versions of the forced heat equation and Maxwell's Equations while the boundary conditions take into account both convective and radiative heat loss. Approximate analytical solutions, valid for small thermal absorptivity, are found for the steady-state temperature and the electric-field amplitude using the Galerkin method. As the Arrhenius law is not amenable analytically, it is approximated by a rational-cubic function. At the steady-state the temperature versus power relationship is found to be multivalued; at the critical power level thermal runaway occurs when the temperature jumps from the lower (cool) temperature branch to the upper (hot) temperature branch of the solution. The approximate analytical solutions are compared with the numerical solutions of the governing equations in the limits of small and large heat-loss and also for an intermediate case involving radiative heat-loss.

Gilthead seabream (Sparus aurata) insulin-like growth factor-I (gsIGF-I) cDNA coding for the mature protein was cloned in a pGEM-3Z vector, and then transferred into prokaryotic expression vector pET-11a and expressed in Escherichia coliBL21(DE3) cells upon induction with isopropyl thiogalactoside. The expressed protein contained within the inclusion-body pellet was solubilized in 4·5 murea, refolded for 24 h at pH 11·3 in the presence of catalytic amounts of cysteine and purified to over 98% purity, as a monomeric methionyl-gsIGF-I. Amino acid composition and N-terminal sequence confirmed the identity to be the predicted protein. Binding assays of the 125I-gsIGF-I to gilthead seabream or carp (Cyprinus carpio) sera resulted in high specific binding, indicating the existence of one or more IGF-binding proteins. In binding experiments to crude gilthead seabream brain homogenate, using human (h) IGF-I as a ligand, the respective IC50value of hIGF-I was about fourfold lower than that of gsIGF-I. Recombinant gsIGF-I exhibited mitogenic activity in a mouse mammary gland-derived MME-L1 cell line which was ∼200-fold lower than that of hIGF-I. Binding experiments to intact MME-L1 cells suggests that this difference most likely results from a correspondingly lower affinity for IGF-I receptor in these cells. In contrast, the activities of gsIGF-I and hIGF-I measured by 35S uptake by gill arches from the goldfish (Carassius auratus) were identical, indicating that the recombinant gsIGF-I is biologically active.Journal of Endocrinology(1997) 153,139–150

The microwave heating of materials is important in many industrial processes. For example, it is used for the smelting of metals and the sintering of ceramics. Hot-spots (localised areas of high temperature) can develop in the material being heated or in the microwave oven itself, with disastrous consequences. Impurities in the material or in a component of the microwave oven can have different electromagnetic and thermal properties to the surrounding material. Different rates of heating occur at these sites, which gives rise to differential heating, which can lead to the generation of hot-spots. The generation of hot-spots by this mechanism is considered for a finite one-dimensional slab with a single impurity at its centre. A fixed-temperature boundary condition is applied at both ends of the slab and one end of the slab is irradiated by microwaves of constant amplitude. The heat absorption at the impurity is assumed to have a power-law dependence on temperature (hence hot-spot generation can occur via thermal runaway). Depending on the electrical and thermal properties of the material there are two possibilities; either a hot-spot occurs or a steady-state solution occurs due to a balance between heat absorption in the material and heat loss through the boundaries. These steady-state solutions are found for both linear and non-linear thermal absorptivity and constant and decaying electric-field amplitude. If possible the region of parameter space in which they occur (in the rest of the parameter space hot-spots occur) is also found. In addition, numerical solutions are developed to verify the steady-state solutions and to investigate cases where analytical solutions are difficult to derive, such as for materials with multiple impurities.

Exact and approximate solutions of the initial—boundary value problem for the Korteweg—de Vries equation on the semi-infinite line are found. These solutions are found for both constant and time-dependent boundary values. The form of the solution is found to depend markedly on the specific boundary and initial value. In particular, multiple solutions and nonsteady solutions are possible. The analytical solutions are compared with numerical solutions of the Korteweg—de Vries equation and are found to be in good agreement.

Reports on a program sponsored by the American Council of Education, a Washington-based non-profit organization, in cooperation with the College of Charleston, South Carolina. Evaluation of corporate training programs by college faculty to determine if the programs may be accepted as college credits; Offer of the program in other states.