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The purpose of this paper is to provide a brief introduction of the finite difference based parabolic equation (PE) modeling to the advanced engineering students and academic researchers.

A three-dimensional parabolic equation (3DPE) model is developed from the ground up for modeling wave propagation in the tunnel via a rectangular waveguide structure. A discussion of vector wave equations from Maxwell’s equations followed by the paraxial approximations and finite difference implementation is presented for the beginners. The obtained simulation results are compared with the analytical solution.

It is shown that the alternating direction implicit finite difference method (FDM) is more efficient in terms of accuracy, computational time and memory than the explicit FDM. The reader interested in maximum details of individual contributions such as the latest achievements in PE modeling until 2021, basic PE derivation, PE formulation’s approximations, finite difference discretization and implementation of 3DPE, can learn from this paper.

For the purpose of this paper, a simple 3DPE formulation is presented. For simplicity, a rectangular waveguide structure is discretized with the finite difference approach as a design problem. Future work could use the PE based FDM to study the possibility of utilization of meteorological techniques, including the effects of backward traveling waves as well as making comparisons with the experimental data.

The proposed work is directly applicable to typical problems in the field of tunnel propagation modeling for both national commercial and military applications.

The purpose of this paper is to investigate health care professionals’ (HCPs) and service-users’ (SUs) attitudes towards different treatment options in an Early Intervention for Psychosis (EIP) service as well as the topical issue of offering choice over treatment.

Seven SUs accessing an EIP service and nine HCPs completed qualitative surveys about treatment for psychosis. Data were analysed thematically.

Both HCPs and SUs appeared to have a generally positive attitude to the range of interventions offered by the EIP service and SUs talked about the importance of all treatment options being explored. There was variation in attitudes towards SUs having choice over their treatment and a number of factors were identified as crucial in influencing attitudes including mental capacity, risk and level of engagement.

Small sample size, recruitment from only one EIP service and using a survey design limit generalisability and depth of analysis.

HCPs working in EIP services should explore different treatment options fully with SUs but be aware that they may feel unable to make the decision themselves. Such discussions should be revisited throughout an individual’s care as their ability and desire to make informed choices may change over time. Continuing Professional Development and clinical supervision should be used to help HCPs reflect on the choice agenda and the implications of this for clinical practice.

Few studies have examined attitudes towards treatments for psychosis. This is an evolving and important clinical area that remains under researched. Recommendations for service-development, future research and clinical practice are made.

DISCUSSION The chromium coating thicknesses used in this work were comparable to those used commercially, being between 70 and 170 micrometres approximately. Even after oxidation for the temperatures and times stated the chromium concentrations at the metal‐oxide interface were between 20% and 60%. These concentrations fell steadily to approximately 13% over the approximate depth stated above before reducing sharply to zero at what was the ferrite‐austenite transformation boundary during the coating process. This is contrary to the structure observed in aluminized stainless steels where a complex structure is produced due to the existence of intermetallic phases. Hence during all the oxidation experiments performed the chromium level of the surface offered for oxidation was never below 13% and complete oxidative breakdown therefore did not occur, excluding spalling effects. Many workers have shown that the oxidation rate of iron‐chromium alloys initially drops sharply with increasing chromium but eventually reaches a minimum of about 20% chromium and then rises for more chromium rich alloys. From the graph of oxidation rate in pure oxygen against chromium content given by Mortimer et al., from 13% chromium to 100% chromium the oxidation rate increases by approximately 6 × 10−9 g.cm−2 sec.−1 It is reasonable to assume that for a diffusion coating the oxidation behaviour will be markedly affected by the composition at its outer surface layer and much less by the composition gradient. If oxidation was continued for sufficiently long periods the latter could affect the general availability of chromium ions for the oxidation process. Over the first 5?m the average chromium levels were between 63% and 20% for the chromised and chrome‐aluminized respectively. From the figures given by Mortimer et al the oxidation rate of the 63% chromium coating would be expected to be 0.5 × 10−9 g.cm−2 sec−1 greater than the 20% chromium coating on the chrome‐aluminized specimens at 600°C, on the basis of the chromium content alone. The results obtained here vary in this manner, hence it is reasonable to conclude that the general oxidation behaviour of the coatings will be very similar to that of pure iron‐chromium alloys containing the same chromium content as in the outer few micrometres of the respective coatings. Even though the true surface area is greater with diffusion treated specimens their oxidation rates are lower that for the corresponding pure alloys.

Heritability studies attempt to estimate the contribution of genes (vs. environments) to variation in phenotypes (or outcomes of interest) in a given population at a given time. This chapter scrutinizes heritability studies of adverse health phenotypes, emphasizing flaws that have become more glaring in light of recent advances in the life sciences and manifest most visibly in epigenetics.

Drawing on a diverse body of research and critical scholarship, this chapter examines the veracity of methodological and conceptual assumptions of heritability studies.

The chapter argues that heritability studies are futile for two reasons: (1) heritability studies suffer from serious methodological flaws with the overall effect of making estimates inaccurate and likely biased toward inflated heritability, and, more importantly (2) the conceptual (biological) model on which heritability studies depend – that of identifiably separate effects of genes versus the environment on phenotype variance – is unsound. As discussed, contemporary bioscientific work indicates that genes and environments are enmeshed in a complex (bidirectional, interactional), dynamic relationship that defies any attempt to demarcate separate contributions to phenotype variance. Thus, heritability studies attempt the biologically impossible. The emerging research on the importance of microbiota is also discussed, including how the commensal relationship between microbial and human cells further stymies heritability studies.

Understandably, few sociologists have the time or interest to be informed about the methodological and theoretical underpinnings of heritability studies or to keep pace with the incredible advances in genetics and epigenetics over the last several years. The present chapter aims to provide interested scholars with information about heritability and heritability estimates of adverse health outcomes in light of recent advances in the biosciences.

Summary A study has been made of the oxidation of a range of chromized and chrome‐aluminized alloys in flowing air and flue gas atmospheres in the temperature range 500°C—900°C. Oxidation data for the full range of alloys are given but only chromized and chrome‐aluminized mild steel are covered in depth.

My goal is to describe my life in marketing over more than 36 years and to help readers better understand (from my personal perspective) the history of marketing. I also aim to lift the curtain on some aspects of service within the marketing community.

This paper is an autobiographical sketch. It describes some key moments in my career, as well as describing how my most cited articles came to be written. It emphasizes the contextual factors at work in different periods, so readers can better understand how and why my research evolved in certain ways. I aim to convey the nature and variety of career experiences that were (and are) open to marketing academics. I discuss my experiences at the Journal of Marketing and the Marketing Science Institute.

Marketing changed rapidly between 1974 and 2017. Although change can be uncomfortable, I urge marketers to seek exposure to new ideas and practices; they are essential to learning and growth. Unexpected opportunities will come along and an alert individual can learn much from them. My time in industry was a learning experience for me. There are many kinds of interesting and successful careers.

The marketing field advances, not by the work of a single individual, but from the accumulated work of the entire marketing community. Everyone has a role to play. I encourage each individual to look for ways to contribute. I offer thoughts on how to build a research career based on my own experience.

My thoughts may shed some light on the experiences of a woman academic and the globalization of marketing academia between 1974 and 2017.

My hope is that this paper contributes to a better understanding of the history of marketing, when it is considered together with other articles on this topic. It may also be useful to people who are embarking upon a career, as well as those seeking to understand the work of earlier marketing scholars.

In the present work, the authors carried out siliconizing, chromizing, aluminizing and chrome‐aluminizing of mild steel in a pack cementation process with a view to evaluate the optimum experimental conditions to obtain satisfactory coatings which possess high resistance to oxidation. It is visualised to adopt some of the experimental conditions in later experiments where diffusion coating treatments are carried out using pastes containing the various diffusion elements. Some of the findings of the authors in siliconizing, chromizing, aluminizing and chrome‐aluminizing of mild steel in pack process are reported. It was observed that there is excess grain growth during siliconizing by the pack process and the coatings are porous and lack good oxidation resistance compared to coatings in the gas phase carried out by other workers. Chromized, aluminized and chrome‐aluminized samples are superior to 18/8 stainless steel and even Inconel in their oxidation resistance. Chromizing followed by aluminizing makes the coating layer less brittle as observed by the micro hardness measurements across the layer and hence chrome‐aluminizing will improve the spoiling resistance of the coatings.

This chapter aims at bringing a sport-centric approach to the study of digital marketing. This is important as most of the existing research on digital marketing takes an industry-neutral perspective that generalises theory to all contexts. The sport industry has been a major recipient of digital marketing so it is important to recognise its impact on the evolution of digital marketing practices. To do so requires an analysis of what digital marketing is and how it has changed as a result of technological innovations. This enables a better understanding about the growth trajectory of digital sport marketing that integrates a sport-specific theory to digital marketing practices.

The purpose of this paper is to integrate the findings of articles appearing in European Journal of Marketing’s special section on covariance-based versus composite-based structural equations modeling (SEM).

This is an editorial which uses literature review to draw conclusions regarding areas of agreement, areas for further research, and changing the discussion around composite-based SEM methods.

There are now four new areas of agreement regarding composite-based SEM. Researchers should adopt a toolbox approach to their methods and know the strengths and weaknesses of the research tools in their toolbox. Partial least squares (PLS) SEM and covariance-based SEM are not substitutes, and it is inappropriate to use the language of confirmatory factor analysis (CFA) in reporting measurement estimates from PLS SEM. Measurement matters and researchers need to devote effort to using reliable and valid multi-item measures in their investigations.

This postscript article outlines recommendations for authors, reviewers and editors regarding the analysis of data and reporting of results using structural equations models.

In connection with the launching as a new British Standard of the revised “Code of Practice for Protective Coating of Iron and Steel Structures Against Corrosion”, the Association of Metal Sprayers published a “Plain Guide to BS 5493: 1977”. The “Plain Guide” introduces the new Code of Practice to owners and managers of structures, consulting engineers, designers, architects and all specifiers of protective systems for steel; it enables them to take advantage of the wealth of information which has been assembled in BS 5493 and which initially might appear to the engineer not intimately involved in corrosion protection. The Guide, main details of which are published below, charts the way through the Standard and should enable everybody more readily to make full use of the information and advice contained within BS 5493. Full copies of “Plain Guide to BS 5493” can be obtained from the Association of Metal Sprayers, Chamber of Commerce, Ward Street, Walsall WS1 2AG, at a cost of 40p each including postage.