Corrosion of aluminium metal in OPC- and CAC-based cement matrices

Corrosion of aluminium metal in ordinary Portland cement (OPC) based pastes produces hydrogen gas and expansive reaction products causing problems for the encapsulation of aluminium containing nuclear wastes. Although corrosion of aluminium in cements has been long known, the extent of aluminium corrosion in the cement matrices and effects of such reaction on the cement phases are not well established. The present study investigates the corrosion reaction of aluminium in OPC, OPC-blast furnace slag (BFS) and calcium aluminate cement (CAC) based systems. The total amount of aluminium able to corrode in an OPC and 4:1 BFS:OPC system was determined, and the correlation between the amount of calcium hydroxide in the system and the reaction of aluminium obtained. It was also shown that a CAC-based system could offer a potential matrix to incorporate aluminium metal with a further reduction of pH by introduction of phosphate, producing a calcium phosphate cement

COVID-19 vaccine hesitancy:a midwifery survey into attitudes towards the COVID-19 vaccine

BACKGROUND: Ethnically minoritised people have been disproportionately affected by the COVID-19 pandemic. Emerging evidence suggests a lower uptake of the vaccine in ethnically minoritised people, particularly Black females of reproductive age. Unvaccinated pregnant women are high risk for morbidity and mortality from COVID-19. Midwives are the principal healthcare professionals responsible for counselling the pregnant population on decisions relating to vaccine uptake. The aim of this study was to explore midwifery uptake of and attitudes towards the COVID-19 vaccine in two ethnically diverse areas. METHODS: A 45-point questionnaire was circulated over a six-week period to midwives employed in two teaching hospitals in England; London (Barts Health NHS Trust) and Sussex (Brighton and Sussex University Hospitals NHS Trust (BSUH)). A total of 378 out of 868 midwives responded. Results were analysed to determine vaccine uptake as well as factors influencing vaccine hesitancy and decision-making between the two trusts and ethnic groups. Thematic analysis was also undertaken. RESULTS: Midwives of Black ethnicities were over 4-times less likely to have received a COVID-19 vaccine compared to midwives of White ethnicities (52% vs 85%, adjusted OR = 0.22, p = < 0.001). Overall, there were no significant differences between trusts in receipt of the COVID-19 vaccine (p = 0.13). Midwives at Barts Health were significantly more likely to have tested positive for COVID-19 compared to midwives at BSUH (adjusted OR = 2.55, p = 0.007). There was no statistical difference between ethnicities in testing positive for COVID-19 (p = 0.86). The most common concerns amongst all participants were regarding the long-term effect of the vaccine (35%), that it was developed too fast (24%), having an allergic reaction (22%) and concerns about fertility (15%). Amongst unvaccinated midwives, those of Black ethnicity had a higher occurrence of concern that the vaccine contained meat / porcine products (adjusted OR = 5.93, p = 0.04) and that the vaccine would have an adverse effect on ethnic minorities (adjusted OR = 4.42, p = 0.03). CONCLUSION: This study highlights the significantly higher level of vaccine hesitancy amongst Black midwives and offer insights into midwives’ concerns. This can facilitate future targeted public health interventions. It is essential that vaccine hesitancy amongst midwifery staff is addressed to improve vaccine uptake in the pregnant population

Artropolis 90 : Lineages & Linkages

Varney documents the processes of organizing and mounting an exhibition of over 200 contemporary British Columbia artists. Includes artist's statements