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Characteristics of the metal powder are a key factor in the success of powder bed fusion (PBF) additive manufacturing. Powders for PBF from different manufacturers may have a different particle size and/or bulk packing and flow behavior. Powder properties change as the powder is reused for multiple builds. This study seeks to measure the variability of commercial 17-4 PH stainless steel powders to determine the effect of powder variability on part density and demonstrate characterization methods that ensure part quality.

Commercial atomized metal powders from four different vendors were produced with two different atomizing gases (N2 and argon). Powder was characterized in both new and extensively reused conditions. All powders were characterized for flow and packing behavior, particle size and internal porosity. Coupons were manufactured using the laser PBF process with optimized scan strategy and exposure parameters. The quality of fabricated parts was measured using bulk density measurement.

Despite differences in powder flowability and particle size, fully dense parts (>99 per cent) were produced using all powders, except one. Residual porosity in these parts appeared to result from gas trapped in the powder particles. The powder with extensive reuse (400+ h in machine fabrication environment) exhibited reduced flowability and increased fraction of fine particles, but still produced full density parts.

This study demonstrates that full density parts can be fabricated using powders with a range of flowability and packing behavior. This suggests that a single flowability measurement may be sufficient for quality assurance in a production environment.

The purpose of this paper is to examine how US school leaders make sense of external mandates, and the way in which their understanding of state and district accountability policies affects their work. It is posited that school leaders’ responses to external accountability are likely to reflect a complex interaction between their perception of the accountability policies, the state and district contexts in which those policies are situated and their own leadership beliefs and practices.

The authors use both principal and teacher survey data to explore the question of how perceptions of external policy are associated with instructional leadership behaviors. Cases of seven principals are employed to flesh out the findings from the survey analysis.

It is concluded that external accountability policy may have a positive impact on instructional leadership – where they see those policies as aligned with their own values and preferences, and where they see their district leaders as supportive of school‐driven accountability initiatives. In these cases, school leaders internalize the external accountability policies and shape them to the particular needs that they see as priorities in their own school. Where one or the other of these factors is weak or missing, on the other hand, leaders demonstrate more negative attitudes to external accountability and weaker instructional leadership.

This analysis draws on a unique, large‐scale data base and uses a mixed methods approach to answer the question.

The current study examines the effect of socialization on the inculcation of professional accounting values. Three sources of socialization are examined: public accounting firms, non-public accounting firms (industry) and accounting professional associations. Specifically, the study compares the professionalism of public and industry accountants. Consistent with expectations, the results suggest that public accountants have stronger beliefs in professional autonomy and self-regulation than industry accountants, and that industry accountants have stronger beliefs in professional affiliation, social obligation and professional dedication than public accountants. It was hypothesized that while professional associations promote all professional values, public accounting firms and industry have different promoting priorities. Public accounting firms foster beliefs in self-regulation and professional autonomy while industry opposes these values, resulting in public accountants having stronger beliefs in these values. Conversely, it was posited that industry encourage beliefs in professional affiliation, social obligation and professional dedication to a greater extent than public accounting firms. The result is that the industry accountants have stronger beliefs in these values than the public accountants. Investigating these issues increase understanding of the importance of the socialization process fostering accounting professional values and identifying areas of potential conflict and reinforcement accountants face when working in public accounting and industry.

From one angle, abortion law appears to confirm the regime politics account of the Supreme Court; after all, the Reagan/Bush coalition succeeded in significantly curtailing the constitutional protection of abortion rights. From another angle, however, it is puzzling that the Reagan/Bush Court repeatedly refused to overturn Roe v. Wade. We argue that time and again electoral considerations led Republican elites to back away from a forceful assertion of their agenda for constitutional change. As a result, the justices generally acted within the range of possibilities acceptable to the governing regime but still typically had multiple doctrinal options from which to choose.

Communications regarding this column should be addressed to Mrs. Cheney, Peabody Library School, Nashville, Term. 37203. Mrs. Cheney does not sell the books listed here. They are available through normal trade sources. Mrs. Cheney, being a member of the editorial board of Pierian Press, will not review Pierian Press reference books in this column. Descriptions of Pierian Press reference books will be included elsewhere in this publication.

The premise that the U.S. Supreme Court never veers too far off from the dominant national political coalition (Dahl, 1957) has become widely accepted among social scientists today. To fulfill that promise, however, the confirmation process for justices must serve as a plebiscite through which the public can ratify or reject future justices based on their views. Unfortunately, modern confirmation hearings have become an exercise in obfuscation, providing little meaningful dialogue on important issues. Because conservative Republican presidents have made the lion's share of appointments in recent times, social conservatives have most often benefited from a process that has severed the link between Supreme Court nominees and the polity they must serve.

Ponders on whether Abraham Flexner was responsible for the change in medical education in North America in the early 20th century, owing to his report of 1910. Tries to demonstrate that medical education in the USA was part of a greater whole of major changes at that time. Concludes, though there was a philanthropic influence, Flexner (who refused to accept credit for change) was not the father of the medical reform plan.