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The paper deals with the use of a Hydrogen Peroxide/Sulphuric Acid etchant in the Through‐Hole Plating system. The relative merits of this solution compared to currently used etchants such as Ammonium Persulphate are discussed on the basis of cost, convenience of operation and ecological effect.

To provide a list of non‐fictional books, as published, for the use of Librarians and Book‐buyers generally, arranged so as to serve as a continuous catalogue of new books ; an aid to exact classification and annotation ; and a select list of new books proposed to be purchased. Novels, school books, ordinary reprints and strictly official publications will not be included in the meantime.

The M & T Chemicals BC925 is a two part system and is based on the following criteria. The redundant film must be removed in the correct form and above all leave the board in a condition for further processing. Once cross‐linked, the polymer is not soluble, so the removal technique is of a mechanical nature, i.e., swelling. Caustic based materials will also swell the film but often cause it to mechanically interlock between the tracks. The degree of swelling of film must also be minimised since, the larger the final film volume, the closer to the solution density it will become. It is then more likely to float around in the solution consuming chemicals and re‐adhering to the board. The M & T BC925 is formulated to break down the film into small high density particles which either settle by gravity or can be removed by a filter system, overcoming the problems previously mentioned.

We discuss the development of achievement motivation from the perspective of Eccles and colleagues’ expectancy-value theory (EVT), focusing on the importance of children developing positive expectancies for success and valuing of achievement to help them cope with change and uncertainty. Although research has shown that, overall, children’s expectancies and values decline, recent studies show many different trajectories in the overall pattern. Children’s expectancies and values predict their school performance and choices of which activities to pursue in and out of school, with these relations getting stronger as children get older. When children’s expectancies and values stay more positive, they can better cope with change and uncertainty, such as the increasing difficulty of many school subjects, or broader changes such as immigrating to a new country. Parents can buffer children’s experiences of change and uncertainty by encouraging them to engage in different activities and by providing them opportunities to do so. Parents’ positive beliefs about their children’s abilities and discussing with them the importance of school can moderate the observed decline in children’s ability beliefs and values. For immigrant and minority children, parents’ emphasis on the importance of school and encouragement of the development of a positive sense of their racial/ethnic identity are critical buffers. Positive teacher–child relations also are a strong buffer, although research indicates that immigrant and minority children often have less positive relations with their teachers. We close with a discussion on recent EVT-based intervention research that shows how children’s beliefs and values for different school subjects can be fostered.

The recent UK Diversity in Sport Governance report (Sport England & UK Sport, 2019) highlighted that two-thirds of boards have no Black, Asian and minority ethnic members and that board diversity is an ongoing problem. In the report, Sport England and UK Sport (2019, p. 5) acknowledged that ‘the sports sector is falling behind other sectors in terms of minority ethic members’. While this is an important acknowledgement, it reflects trends in both research and policy on diversity in UK sport governance that continue to focus on single forms of discrimination (e.g., gender, ethnicity, age or sexuality). In this chapter we move beyond this approach to consider how Black women experience sport leadership and governance through an intersectional lens. The key findings in this paper outline Black women's positionality at the intersections of race and gender and how these influence their sport leadership opportunities and experiences based on (1) their outsider within status, (2) inequities in their salaries, marginalising promotions and occupational stereotyping, (3) their identity negotiation and (4) their experiences with womanism. We conclude by arguing for more research that explores the intersection of race and gender within UK sport leadership and governance, which should be positioned within the context of long-standing and deep-rooted racialised and gendered ideology and beliefs within UK society.

A study of the published statements of Australian school administrators revealed that two distinctive configurations of power and service relationships are projected in their publically presented images of state school administration as it relates to government and the public. A previous Traditional Centralist‐Unity configuration is now being replaced by an Emergent Devolution‐Diversity conformation. Analysis was directed to (a) understanding the significance of the two images in terms of their function as public communications, and (b) accounting for the shift in the imagery in the light of pressures for change, the way administrators are interpreting change as turbulence, and the projection of counter images incorporating critiques of government school systems. To help organise analysis, it was assumed that images of system administration have the potential to communicate: 1. information, 2. explanation, 3. judgements and value positions, 4. statements designed to advance sectional interests, and 5. themes and persuasive symbols. It was also assumed that the shift in the public images of administrators may be studied in the way their images relate to three basic sources of administrative tension: tensions which arise from problems of meaning, problems of aspiration, and problems of practice.

Did a set of examiner's reports written on educational theses subscribe to a common view of critical thinking? An analysis indicated that an idealized style of critical thinking was embodied in examiners' comments, one which combined the imagery of detached rationality with the imagery of imaginative insight. This functional definition, applied for the purpose of assessment, appears to represent a mixture of assumptions taken from traditional and emergent research traditions in educational administration. It is conjectured that this functional definition may represent a negotiated meaning, arrived at in the light of conflicting intellectual and cultural pressures experienced in the academic study of educational administration.

We review the interventions that promote motivation in academic contexts, with a focus on two primary questions: How can we motivate students to take more STEM courses? Once in those STEM courses, how can we keep students motivated and promote their academic achievement?

We have approached these two motivational questions from several perspectives, examining the theoretical issues with basic laboratory research, conducting longitudinal questionnaire studies in classrooms, and developing interventions implemented in different STEM contexts. Our research is grounded in three theories that we believe are complementary: expectancy-value theory (Eccles & Wigfield, 2002), interest theory (Hidi & Renninger, 2006), and self-affirmation theory (Steele, 1988). As social psychologists, we have focused on motivational theory and used experimental methods, with an emphasis on values – students’ perceptions of the value of academic tasks and students’ personal values that shape their experiences in academic contexts.

We review the experimental field studies in high-school science and college psychology classes, in which utility-value interventions promoted interest and performance for high-school students in science classes and for undergraduate students in psychology courses. We also review a randomized intervention in which parents received information about the utility value of math and science for their teens in high school; this intervention led students to take nearly one semester more of science and mathematics, compared with the control group. Finally, we review an experimental study of values affirmation in a college biology course and found that the intervention improved performance and retention for first-generation college students, closing the social-class achievement gap by 50%. We conclude by discussing the mechanisms through which these interventions work.

These interventions are exciting for their broad applicability in improving students’ academic choices and performance, they are also exciting regarding their potential for contributions to basic science. The combination of laboratory experiments and field experiments is advancing our understanding of the motivational principles and almost certainly will continue to do so. At the same time, interventions may benefit from becoming increasingly targeted at specific motivational processes that are effective with particular groups or in particular contexts.

IT is fitting that a new series of this magazine should be introduced by some reflections on the whole question of book selection, both for the general public and libraries.

The research community currently employs four very different versions of the social network concept: A social network is seen as a set of socially constructed role relations (e.g., friends, business partners), a set of interpersonal sentiments (e.g., liking, trust), a pattern of behavioral social interaction (e.g., conversations, citations), or an opportunity structure for exchange. Researchers conventionally assume these conceptualizations are interchangeable as social ties, and some employ composite measures that aim to capture more than one dimension. Even so, important discrepancies often appear for non-ties (as dyads where a specific role relation or sentiment is not reported, a specific form of interaction is not observed, or exchange is not possible).

Investigating the interplay across the four definitions is a step toward developing scope conditions for generalization and application of theory across these domains.

This step is timely because emerging tools of computational social science – wearable sensors, logs of telecommunication, online exchange, or other interaction – now allow us to observe the fine-grained dynamics of interaction over time. Combined with cutting-edge methods for analysis, these lenses allow us to move beyond reified notions of social ties (and non-ties) and instead directly observe and analyze the dynamic and structural interdependencies of social interaction behavior.

This unprecedented opportunity invites us to refashion dynamic structural theories of exchange that advance “beyond networks” to unify previously disjoint research streams on relationships, interaction, and opportunity structures.