Development of sputtered techniques for thrust chambers, task 1

Filler materials proposed for use in the sputter fabrication regeneratively cooled thrust chambers were evaluated. Low melting castable alloys, CERROBEND. CERROCAST, and CERROTRU, slurry applied SERMETEL 481 and flame-sprayed aluminum were investigated as filler materials. Sputter deposition from a cylindrical cathode inverted magnestron was used to apply an OFHC copper closeout layer to filled OFHC copper ribbed-wall cylindrical substrates. The sputtered closeout layer structure was evaluated with respect to filler material contamination, predeposition machining and finishing operations, and deposition parameters. The application of aluminum by flame-spraying resulted in excessiver filler porosity. Though the outgassing from this porosity was found to be detrimental to the closeout layer structure, bond strengths in excess of 10,500 psi were achieved. Removal of the aluminum from the grooves was readily accomplished by leaching in a 7.0 molar solution of sodium hydroxide at 353 K. Of the other filler materials evaluated, CERROTRU was found to be the most suitable material with respect to completely filling the ribbed-wall cylinders and vacuum system compatibility. However, bond contamination resulted in low closeout layer bond strength with the CERROTRU filler. CERROBEND, CERROCAST, and SERMETEL 481 were found to be unacceptable as filler materials

Development of sputtered techniques for thrust chambers

Techniques and materials were developed and evaluated for the fabrication and coating of advanced, long life, regeneratively cooled thrust chambers. Materials were analyzed as fillers for sputter application of OFHC copper as a closeout layer to channeled inner structures; of the materials evaluated, aluminum was found to provide the highest bond strength and to be the most desirable for chamber fabrication. The structures and properties were investigated of thick sputtered OFHC copper, 0.15 Zr-Cu, Al2O3,-Cu, and SiC-Cu. Layered structures of OFHC copper and 0.15 Zr-Cu were investigated as means of improving chamber inner wall fatigue life. The evaluation of sputtered Ti-5Al-2.5Sn, NASA IIb-11, aluminum and Al2O3-Al alloys as high strength chamber outer jackets was performed. Techniques for refurbishing degraded thrust chambers with OFHC copper and coating thrust chambers with protective ZrO2 and graded ZrO2-copper thermal barrier coatings were developed

Intersectional impact of multiple identities on social work education in the UK

This document is the Accepted Manuscript version of the following article: Ben Chi-pun Liu, ‘Intersectional impact of multiple identities on social work education in the UK’, Journal of Social Work, Vol 17(2): 226-242, March 2017. © 2016 The Author(s). DOI to the published version: 10.1177/1468017316637220. Reprinted by permission of SAGE Publications.Summary: The study reviews the records of 671 social work students and graduates including the seven intakes from the first cohort in 2003/2004 to the intake in 2010/2011 to examine the interacting effect of learning difficulties, ethnicity and gender on the completion of social work training at a university in the South East of England. Findings: Among the students, 79.9% of them were female, 50.1% were black, 27.9% white, 10.7% Asian and 11.3% other ethnicities. A majority of students did not report any disability. Among those who did (n ¼ 84), 52.3% (n ¼ 44) reported a learning difficulty.The percentage of students who have successfully completed the training is 76.4%, a completion rate that is comparable to the UK’s national figure. Having controlled the confounding variables, hierarchical logistic regression identified the risk factor for dropoutfrom undergraduate social work programme as black female students with learning difficulties (odds ratio ¼ 0.100, 95% confidence interval ¼ 0.012–0.862, p < 0.05). Findings suggested that students with multiplicity of identities, i.e. being black and female and with a learning difficulty, have a lower probability to complete the programme successfully. Applications: Strategies for tackling the intersecting disadvantages of race, gender and disabilities in social work training should embrace three principles: providing continuous support, focusing on how the support is provided and addressing contextual and structural barriers.Peer reviewedFinal Accepted Versio

Mechanisms for introducing large medical devices into developing countries. Avoiding the pitfalls of the past and providing possible solutions for the future

The predicted emergence of cancer as a major NCD in developing countries by 2020 has already prompted some governments to invest in cancer treatment. The large medical devices required to provide comprehensive radiotherapy are both expensive to purchase and to install. Manufacturers have therefore started producing a range of large medical devices which are specifically designed for the emerging market in developing countries. This market, however, can produce unforeseen problems. The lack of experience of the logistics involved in the delivery and installation of such large pieces of equipment can often lead to underestimations in time scales by the recipients. Advice and assistance on the clinical procurement process is essential for avoiding long delays. Within the UK, the lifecycle of radiotherapy machines can often be ten years or less, which in most cases is well below the actual lifetime of the machines. Therefore many machines are decommissioned to be scrapped well within the usable equipment lifetime. However, if decommissioning was performed so that the machine could be salvaged, the extra cost would be relatively low. Such machines could be serviced and donated to developing countries allowing them to increase their radiotherapy coverage greatly for the cost of the decommissioning, servicing and installation process. Therefore it would seem that with a small change to the decommissioning process of large medical devices, developing countries who could benefit from equipment, which otherwise would be scrapped, could attain a large number of life changing pieces of equipment within their tight budgetary constraints and make a real impact on the predicted increase in cancer deaths

Interim Report deliverable for GLO 002/10: General IRI Planning and Technical Support for Harita Micro-Insurance Pilot.

This is the technical annex to HARITA IRI Report to Oxfam America. It is the interim Report deliverable for GLO 002/10: General IRI Planning and Technical Support for Harita Micro-Insurance Pilot and contains background material useful for the main report

Assessing the Role of CD103 in Immunity to an Intestinal Helminth Parasite

In the intestine, the integrin CD103 is expressed on a subset of T regulatory (T(reg)) cells and a population of dendritic cells (DCs) that produce retinoic acid and promote immune homeostasis. However, the role of CD103 during intestinal helminth infection has not been tested.We demonstrate that CD103 is dispensable for the development of protective immunity to the helminth parasite Trichuris muris. While we observed an increase in the frequency of CD103(+) DCs in the lamina propria (LP) following acute high-dose infection with Trichuris, lack of CD103 had no effect on the frequency of CD11c(+) DCs in the LP or mesenteric lymph nodes (mLN). CD103-deficient (CD103(-/-)) mice develop a slightly increased and earlier T cell response but resolve infection with similar kinetics to control mice. Similarly, low-dose chronic infection of CD103(-/-) mice with Trichuris resulted in no significant difference in immunity or parasite burden. Absence of CD103 also had no effect on the frequency of CD4(+)CD25(+)Foxp3(+) T(reg) cells in the mLN or LP.These results suggest that CD103 is dispensable for intestinal immunity during helminth infection. Furthermore, lack of CD103 had no effect on DC or T(reg) recruitment or retention within the large intestine