418 research outputs found

    Difficult separations

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    Reservoir resilience of viscoelastic surfactants

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    Viscoelastic solutions are notoriously sensitive to temperature and ionic strength. In order to be applicable for use in oil reservoirs, they need to be resilient to higher temperatures as well as to saline content. We define the essential characteristics required. Refractory properties obtained under Couette testing do not necessarily provide the same performance under pressure-driven flow. Nonetheless, it is possible to formulate solutions which clearly indicate that subsurface application is practicable. We show examples where salinity enables significantly enhanced viscoelasticity above ambient temperatures

    "I am your mother and your father!": In vitro derived gametes and the ethics of solo reproduction

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    In this paper, we will discuss the prospect of human reproduction achieved with gametes originating from only one person. According to statements by a minority of scientists working on the generation of gametes in vitro, it may become possible to create eggs from men’s non-reproductive cells and sperm from women’s. This would enable, at least in principle, the creation of an embryo from cells obtained from only one individual: ‘solo reproduction’. We will consider what might motivate people to reproduce in this way, and the implications that solo reproduction might have for ethics and policy. We suggest that such an innovation is unlikely to revolutionise reproduction and parenting. Indeed, in some respects it is less revolutionary than in vitro fertilisation as a whole. Furthermore, we show that solo reproduction with in vitro created gametes is not necessarily any more ethically problematic than gamete donation—and probably less so. Where appropriate, we draw parallels with the debate surrounding reproductive cloning. We note that solo reproduction may serve to perpetuate reductive geneticised accounts of reproduction, and that this may indeed be ethically questionable. However, in this it is not unique among other technologies of assisted reproduction, many of which focus on genetic transmission. It is for this reason that a ban on solo reproduction might be inconsistent with continuing to permit other kinds of reproduction that also bear the potential to strengthen attachment to a geneticised account of reproduction. Our claim is that there are at least as good reasons to pursue research towards enabling solo reproduction, and eventually to introduce solo reproduction as an option for fertility treatment, as there are to do so for other infertility related purposes

    Children with lesbian parents: A community study

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    Existing research on children with lesbian parents is limited by reliance on volunteer or convenience samples. The present study examined the quality of parent-child relationships and the socio-emotional and gender development of a community sample of 7-year-old children with lesbian parents. Families were recruited through the Avon Longitudinal Study of Parents and Children, a geographic population study of 14,000 mothers and their children. Thirty-nine lesbian-mother families, 74 two-parent heterosexual families, and 60 families headed by single heterosexual mothers were compared on standardized interview and questionnaire measures administered to mothers, co-mothers/fathers, children, and teachers. Findings are in line with those of earlier investigations showing positive mother-child relationships and well-adjusted children

    Love and Truth: What Really Matters for Children Born Through Third‐Party Assisted Reproduction

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    Abstract: Ever since the birth of the first baby born through in vitro fertilization in 1978, advances in reproductive technologies have raised new concerns about the outcomes for children. In this article, I summarize research on children born through assisted reproduction involving a third party, that is, children born through egg donation, sperm donation, and surrogacy, with particular attention to the findings of a longitudinal study of children born to heterosexual couples in the United Kingdom. The assisted reproduction families generally showed high levels of family functioning and children's adjustment from early childhood through to adolescence, suggesting that biological relatedness is less important than positive parent–child relationships for the well‐being of children conceived by third‐party assisted reproduction. Similarly, studies of families created by third‐party reproduction with two mothers, single mothers, two fathers, and single fathers have shown that these families function well

    Transition to parenthood and quality of parenting among gay, lesbian and heterosexual couples who conceived through assisted reproduction

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    Little research has focused on the emotions felt during pregnancy and early parenthood as well as the initial quality of parenting displayed by first-time parents who conceived using assisted reproduction technologies (surrogacy, donor insemination, and in vitro fertilization). Research on primary and secondary caregivers in gay, lesbian, and heterosexual families is especially sparse. The current study examined 35 gay-father families, 58 lesbian-mother families and 41 heterosexual-parent families with their infants. Families were assessed at home when their infants were 4 months old (±14 days), and each parent participated in an audio-recorded standardized semi-structured interview in which we explored parental feelings during pregnancy, feelings about the parental role, perceived parental competence, the enjoyment of parenthood, expressed warmth and emotional over-involvement of parents. 13 Heterosexual parents reported less positive feelings in early pregnancy than lesbian parents, while gay parents reported less positive feelings at the end of pregnancy than lesbian mothers and more positive feelings about parenthood during the first post-partum weeks than heterosexual parents. There was no interaction between family type and caregiver role on reported feelings, or on perceived competence, enjoyment, warmth, and involvement. The present findings elucidate the transition to parenthood among first-time parents conceiving through assisted reproductive technologies, and especially contribute to our knowledge about gay fathers who became parents through surrogacy

    Negotiating daughterhood and strangerhood: retrospective accounts of serial migration

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    Most considerations of daughtering and mothering take for granted that the subjectivities of mothers and daughters are negotiated in contexts of physical proximity throughout daughters’ childhoods. Yet many mothers and daughters spend periods separated from each other, sometimes across national borders. Globally, an increasing number of children experience life in transnational families. This paper examines the retrospective narratives of four women who were serial migrants as children (whose parents migrated before they did) . It focuses on their accounts of the reunion with their mothers and how these fit with the ways in which they construct their mother-daughter relationships. We take a psychosocial approach by using a psychoanalytically-informed reading of these narratives to acknowledge the complexities of the attachments produced in the context of migration and to attend to the multi-layered psychodynamics of the resulting relationships. The paper argues that serial migration positioned many of the daughters in a conflictual emotional landscape from which they had to negotiate ‘strangerhood’ in the context of sadness at leaving people to whom they were attached in order to join their mothers (or parents). As a result, many were resistant to being positioned as daughters, doing daughtering and being mothered in their new homes

    Adoptive gay father families: parent-child relationships and children's psychological adjustment

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    Findings are presented on a U.K. study of 41 gay father families, 40 lesbian mother families, and 49 heterosexual parent families with an adopted child aged 3–9 years. Standardized interview and observational and questionnaire measures of parental well-being, quality of parent–child relationships, child adjustment, and child sex-typed behavior were administered to parents, children, and teachers. The findings indicated more positive parental well-being and parenting in gay father families compared to heterosexual parent families. Child externalizing problems were greater among children in heterosexual families. Family process variables, particularly parenting stress, rather than family type were found to be predictive of child externalizing problems. The findings contribute to theoretical understanding of the role of parental gender and parental sexual orientation in child development
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