32 research outputs found

    An alternative synthesis method for di calcium phosphate (monetite) powders from mediterranean mussel (mytilus galloprovincialis) shells

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    Marine species, such as corals, sea shells and nacres, attract special interest in bioceramics field for bone graft, bone cements and drug delivery applications. Most of the marine structures are made up of pure calcium carbonate (calcite or aragonite) with a very small amount of an organic matrix. In the past the most common way to transform these structures to hydroxyapatite was hydrothermal transformation method. This current work introduces a new approach for producing fine powders of calcium phosphates from Mediterranean mussel (Mytilus galloprovincialis) shells. A comparative study was carried out to investigate the differences of these powders under only hot plate heating and hot plate heating together with ultrasonic agitation while H3PO4 was added. The temperature of the hotplate was kept constant at 80 degrees C and then, H3PO4 was added drop wise into the solution for 2 hrs. The mixture was then placed into an oven at 100 degrees C for 24 hrs. They were further calcined at 800 degrees C for 3 hrs. XRD, FTIR. and ICP-MS were used to identify the structure and composition. It was found that the final powders were predominantly monetite, with some tricalcium phosphate as a secondary phase. This relatively simple and efficient method can be easily applied to produce calcium phosphate precursor powders for a range of biomedical applications

    Calcium phosphate formation from sea urchin - (brissus latecarinatus) via modified mechano-chemical (ultrasonic) conversion method

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    This study aims to produce apatite structures, such as hydroxyapatite (HA) and fluorapatite (FA), from precursor calcium phosphates of biological origin, namely from sea urchin, with mechano-chemical stirring and hot-plating conversion method. The produced materials were heat treated at 800 °C for 4 hours. X-ray diffraction and scanning electron microscopy (SEM) studies were conducted. Calcium phosphate phases were developed. The SEM images showed the formation of micro to nano-powders. The experimental results suggest that sea urchin, Brissus latecarinatus skeleton could be an alternative source for the production of various mono or biphasic calcium phosphates with simple and economic mechano-chemical (ultrasonic) conversion method

    Gender equality and religion:a multi-faith exploration of young adults’ narratives

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    This paper presents findings from research on young adults in the UK from diverse religious backgrounds. Utilizing questionnaires, interviews, and video diaries it assesses how religious young adults understood and managed the tensions in popular discourse between gender equality as an enshrined value and aspirational narrative, and religion as purportedly instituting gender inequality. We show that, despite varied understandings, and the ambivalence and tension in managing ideal and practice, participants of different religious traditions and genders were committed to gender equality. Thus, they viewed gender-unequal practices within their religious cultures as an aberration from the essence of religion. In this way, they firmly rejected the dominant discourse that religion is inherently antithetical to gender equality

    The employment of migrant nannies in the UK: negotiating social class in an open market for commoditised in-home care

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    Migrant women are important sources of labour in the commoditised in-home childcare sector in many regions of the UK. Jobs in this sector, which include nannies as well as au pairs, babysitters, housekeepers and mothers' helps, are often low paid and low status with pay and conditions being determined by employers' circumstances and whims. This article draws on primary data and secondary sources to illustrate the ways in which employers compare migrant nannies with British nannies and other childcare workers in terms of the social class and formal education levels of different groups, with the aim of explaining why migrants are perceived as high-quality candidates for what are often low-paid, low-status jobs. I argue that employers negotiate inter-class relations in this gendered form of employment by understanding their relationship with the migrant nannies they have employed in the context of broader global inequalities—these inequalities are then reproduced and reaffirmed in private homes and across UK culture and society
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