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THE preservation of the eyes and the ability to make the best use of them are obviously of the utmost importance to all those concerned with aviation, whether in connexion with flying itself or with aircraft production.

TO those who properly understand the effect on industrial production of efficient lighting, it has come as no surprise that the Departmental Committee on lighting in factories has recommended a new standard of intensities. The fact remains, however, that many installations have been automatically rendered out‐of‐date. For this reason factory executives of works engaged on all manner of processes have to face the problem of modernizing their lighting schemes and are consequently seeking guidance on the accomplishment of this object in the most expeditious, efficient and economic manner.

The purpose of this paper is to investigate the effect of different heating approaches during thermal rounding of polymer powders on powder bulk properties such as particle size, shape and flowability, as well as on the yield of process.

This study focuses on the rounding of commercial high-density polyethylene polymer particles in two different downer reactor designs using heated walls (indirect heating) and preheated carrier gas (direct heating). Powder bulk properties of the product obtained from both designs are characterized and compared.

Particle rounding with direct heating leads to a considerable increase in process yield and a reduction in powder agglomeration compared to the design with indirect heating. This subsequently leads to higher powder flowability. In terms of shape, indirect heating yields not only particles with higher sphericity but also entails substantial agglomeration of the rounded particles.

Shape modification via thermal rounding is the decisive step for the success of a top-down process chain for selective laser sintering powders with excellent flowability, starting with polymer particles from comminution. This report provides new information on the influence of the heating mode (direct/indirect) on the performance of the rounding process and particle properties.

Father involvement is a salient predictor of children’s development and recent studies suggest that African American fathers who are highly involved across infancy and toddlerhood have children who enter school better prepared to succeed. Little is known, however, about the specific dimensions of fathering (e.g., language stimulation) that contribute to the positive development of African American children during the early childhood period. Even less is known about psychological and contextual barriers to positive father involvement among African American men with very young children. The first part of this chapter briefly reviews empirical research that has delineated links between multiple dimensions of father involvement and child development in African American families. The second part of the chapter explores emerging evidence on the associations between fathers’ psychological functioning, father involvement and child development, and concludes with suggestions for future research, practice, and policy.

Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.

The dynamic stability of nano-tubes is an important issue in engineering applications. Dynamic stability of anti-symmetric coupled-carbon nanotubes (C-CNTs)-systems in thermal environment is presented in this paper. In this system, the top and bottom CNTs are subjected to axial harmonic load and action of the viscous fluid, respectively.

The coupling and surrounding mediums of the CNTs are simulated by visco-Pasternak foundation containing the spring, shear and damper coefficients. Based on the Timoshenko beam theory and Hamilton’s principle, the coupled motion equations are derived considering size effects using Eringen’s nonlocal theory. Using the exact solution in conjunction with Bolotin’s method, the dynamic instability region (DIR) of the coupled structure is obtained. The effects of various parameters such as small scale parameter, Knudsen number, fluid velocity, static load factor, temperature change, surrounding medium and nanotubes aspect ratio are shown on the DIR of the coupled system.

Results indicate that considering parameters such as small scale effects, static load factor, Knudsen number and fluid velocity shifts the DIR of C-CNTs to a lower frequency zone.

To the best of our knowledge, analyses of anti-symmetric coupled CNTs have not received enough attentions so far. In order to optimize the nanostructures designing, the main purpose of the present paper is to investigate nonlocal dynamic stability of CNTs subjected to axial harmonic load coupled with CNTs conveying fluid.

In 1920 Margaret Sanger called voluntary motherhood “the key to the temple of liberty” and noted that women were “rising in fundamental revolt” to claim their right to determine their own reproductive fate (Rothman, 2000, p. 73). Decades later Barbara Katz Rothman reflected on the social, political and legal changes produced by reproductive-rights feminists since that time. She wrote: So the reproductive-rights feminists of the 1970s won, and abortion is available – just as the reproductive-rights feminists of the 1920s won, and contraception is available. But in another sense, we did not win. We did not win, could not win, because Sanger was right. What we really wanted was the fundamental revolt, the “key to the temple of liberty.” A doctor’s fitting for a diaphragm, or a clinic appointment for an abortion, is not the revolution. It is not even a woman-centered approach to reproduction (2000, p. 79).

This chapter draws on developmental intergroup theory, parental ethnic-racial socialization literature, anti-bias curricula, and prejudice intervention studies to address the appropriateness of discussing race and racism in early childhood settings. Existing literature about teacher discussions surrounding race and racism is reviewed, best practices are shared, and the need for more research in this area is highlighted. The construct of parental ethnic-racial socialization is mapped onto early childhood anti-bias classroom practices. The chapter also outlines racial ideologies of teachers, specifically anti-bias and colorblind attitudes, and discusses how these ideologies may manifest in classroom practices surrounding race and racism. Colorblind ideology is problematized and dissected to show that colorblind practices may harm children. Young children’s interpretations of race and racism, in light of children’s cognitive developmental level, are discussed. Additionally, findings from racial prejudice intervention studies are applied to teaching. Early literacy practices surrounding race and racism are outlined with practical suggestions for teachers and teacher educators. Moreover, implications of teacher practices surrounding race and racism for children’s development, professional development, and teacher education are discussed.

Nurse navigators (NNs) coordinate patient care, improve care quality and potentially reduce healthcare resource use. The purpose of this paper is to undertake an evaluation of hospitalisation outcomes in a new NN programme in Queensland, Australia.

A matched case-control study was performed. Patients under the care of the NNs were randomly selected (n=100) and were matched to historical (n=300) and concurrent (n=300) comparison groups. The key outcomes of interest were the number and types of hospitalisations, length of hospital stay and number of intensive care unit days. Generalised linear and two-part models were used to determine significant differences in resources across groups.

The control and NN groups were well matched on socio-economic characteristics, however, groups differed by major disease type and number/type of comorbidities. NN patients had high healthcare needs with 53 per cent having two comorbidities. In adjusted analyses, compared with the control groups, NN patients showed higher proportions of preventable hospitalisations over 12 months, similar days in intensive care and a smaller proportion had overnight stays in hospital. However, the NN patients had significantly more hospitalisations (mean: 6.0 for NN cases, 3.4 for historical group and 3.2 for concurrent group); and emergency visits.

As many factors will affect hospitalisation rates beyond whether patients receive NN care, further research and longer follow-up is required.

A matched case-control study provides a reasonable but insufficient design to compare the NN and non-NN exposed patient outcomes.