362 research outputs found
The coevolutionary biology of brood parasitism : a call for integration
Obligate brood-parasitic cheats have fascinated natural historians since ancient times. Passing on the costs of parental care to others occurs widely in birds, insects and fish, and often exerts selection pressure on hosts that in turn evolve defences. Brood parasites have therefore provided an illuminating system for researching coevolution. Nevertheless, much remains unknown about howecology and evolutionary history constrain or facilitate brood parasitism, or the mechanisms that shape or respond to selection. In this special issue, we bring together examples fromacross the animal kingdomto illustrate the diverseways in which recent research is addressing these gaps. This special issue also considers how research on brood parasitism may benefit from, and in turn inform, related fields such as social evolution and immunity. Here, we argue that progress in our understanding of coevolution would benefit from the increased integration of ideas across taxonomic boundaries and across Tinbergen's Four Questions: mechanism, ontogeny, function and phylogeny of brood parasitism. We also encourage renewed vigour in uncovering the natural history of the majority of the world's brood parasites that remain little-known. Indeed, it seems very likely that some of nature's brood parasites remain entirely unknown, because otherwise we are left with a puzzle: if parental care is so costly, why is brood parasitism not more common? This article is part of the theme issue 'The coevolutionary biology of brood parasitism: from mechanism to pattern'.Non peer reviewe
Cancer incidence in British vegetarians
Background:
Few prospective studies have examined cancer incidence among vegetarians.
Methods:
We studied 61 566 British men and women, comprising 32 403 meat eaters, 8562 non-meat eaters who did eat fish ('fish eaters') and 20 601 vegetarians. After an average follow-up of 12.2 years, there were 3350 incident cancers of which 2204 were among meat eaters, 317 among fish eaters and 829 among vegetarians. Relative risks (RRs) were estimated by Cox regression, stratified by sex and recruitment protocol and adjusted for age, smoking, alcohol, body mass index, physical activity level and, for women only, parity and oral contraceptive use.
Results:
There was significant heterogeneity in cancer risk between groups for the following four cancer sites: stomach cancer, RRs (compared with meat eaters) of 0.29 (95% CI: 0.07–1.20) in fish eaters and 0.36 (0.16–0.78) in vegetarians, P for heterogeneity=0.007; ovarian cancer, RRs of 0.37 (0.18–0.77) in fish eaters and 0.69 (0.45–1.07) in vegetarians, P for heterogeneity=0.007; bladder cancer, RRs of 0.81 (0.36–1.81) in fish eaters and 0.47 (0.25–0.89) in vegetarians, P for heterogeneity=0.05; and cancers of the lymphatic and haematopoietic tissues, RRs of 0.85 (0.56–1.29) in fish eaters and 0.55 (0.39–0.78) in vegetarians, P for heterogeneity=0.002. The RRs for all malignant neoplasms were 0.82 (0.73–0.93) in fish eaters and 0.88 (0.81–0.96) in vegetarians (P for heterogeneity=0.001).
Conclusion:
The incidence of some cancers may be lower in fish eaters and vegetarians than in meat eaters
Facing Forward, Nine stories about being a survivor of human trafficking in a post-trafficking shelter in the Netherlands
This report describes nine stories of six women and three men who recently exited a human trafficking
situation and, at the time of this research, resided in a shelter for foreign victims of trafficking
in the Netherlands. It speaks about their hopes and dreams, their fears and frustrations, and
describes how they feel social and health care might be improved. The report’s aim is to shed more
light on service users’ views on post-trafficking service provision for everyone directly (e.g. social
workers, psychologists and general practitioners) and indirectly (e.g. managers and policymakers)
involved with providing care to this group.
The main message from the report is that victims of human trafficking in a post-trafficking shelter
can be expected to exhibit a strong desire to move forward and establish a meaningful life with a
job, a family and friends. This is an important conclusion: it shows that besides the ‘trauma’-narrative
that is often stressed in the literature as being important among trafficking survivors, the
‘future‘-narrative is as important and should be taken into account in developing social and health
services for this group. Despite the importance of being able to pursue a meaningful life to them,
service users in this study were often stunted in doing just that. Through barriers in finding work,
education and a place to live, often caused by their residency status, a feeling of being ostracized
in Dutch society and shelter policies, service users often felt ‘in limbo’: standing still, without being
able to change that situation. Regardless of this, and seemingly against all odds, service users still
pursued their goals, by engaging in Dutch language courses, participating in vocational skills training
and engaging in volunteer work. These activities were described as useful by participants and therefore
preferable over other activities. Service users found them useful because they provided them
with opportunities to work towards their envisioned futures.
Hoping for the fulfilment of their goals and pursuing them in these ways likely allowed service users
to better cope with their problems in the present and improved their well-being. For this reason,
it is essential that social and health provision for this group supports and facilitates service users’
forwards-facing, future-orientated views, in addition to providing trauma-informed services. But
do not take our word for it: please read the stories in this report and get to know these men and
women, and read about what they, in their own words, feel service provision ought to look like in a
post-trafficking shelter
The development of national competency standards for the midwife in Australia
Objective: to develop and validate national competency standards for midwives in Australia. This study was part of a commissioned national research project to articulate the scope of practice of Australian midwives and to develop national competency standards to assist midwives to deliver safe and competent midwifery care. Design: a multi-method, staged approach was used to collect data through a literature review, workshop consultations, interviews, surveys and written submissions in order to develop national competency standards for Australian midwives. Subsequently, direct observation of practice in a range of settings ensured validation of the competencies. Setting: maternity-care settings in each state and territory in Australia. Participants: midwives, other health professionals and consumers of midwifery care. Findings: The national competency standards for the midwife were developed through research and consultation before being validated in practice. Key conclusions: the national competency standards are currently being implemented into education, regulation and practice in Australia. These will be minimum competency standards required of all midwives who seek authority to practise as a midwife in Australia. It is expected that all midwives will demonstrate that they are able to meet the competency standards relevant to the position they hold. Implications for practice: the competency standards establish a national standard for midwives and reinforce responsibility and accountability in the provision of quality midwifery care through safe and effective practice. In addition, individual midwives may use the competency standards as the basis of their ongoing professional development plans. © 2006 Elsevier Ltd. All rights reserved
The role of the midwife in Australia: views of women and midwives
Objective: to research the role of midwives in Australia from the perspectives of women and midwives. This study was part of a commissioned national research project to articulate the scope of practice of Australian midwives and to develop national competency standards to assist midwives to deliver safe and competent midwifery care. Design: a multi-method approach with qualitative data collected from surveys with women and interviews with midwives. Setting: participants represented each state and territory in Australia. Participants: midwives who were randomly selected by the regulatory authorities across the country and women who were consumers of midwifery care and involved in maternity activism. Key conclusions: midwives and women identified a series of key elements that were required of a midwife. These included: being woman centred; providing safe and supportive care; and working in collaboration with others when necessary. These findings were consistent with much of the international literature. Implications for practice: a number of barriers to achieving the full role of the midwife were identified. These included a lack of opportunity to practice across the full spectrum of maternity care, the invisibility of midwifery in regulation and practice, the domination of medicine, workforce shortages, the institutional system of maternity care, and the lack of a clear image of what midwifery is within the wider community. These barriers must be addressed if midwives in Australia are to be able to function according to the full potential of their role. © 2007
Hosts elevate either within-clutch consistency or between-clutch distinctiveness of egg phenotypes in defence against brood parasites
In host-parasite arms races, hosts can evolve signatures of identity to enhance the detection of parasite mimics. In theory, signatures are most effective when within-individual variation is low ('consistency'), and between-individual variation is high ('distinctiveness'). However, empirical support for positive covariation in signature consistency and distinctiveness across species is mixed. Here, we attempt to resolve this puzzle by partitioning distinctiveness according to how it is achieved: (i) greater variation within each trait, contributing to elevated 'absolute distinctiveness' or (ii) combining phenotypic traits in unpredictable combinations ('combinatorial distinctiveness'). We tested how consistency covaries with each type of distinctiveness by measuring variation in egg colour and pattern in two African bird families (Cisticolidae and Ploceidae) that experience mimetic brood parasitism. Contrary to predictions, parasitized species, but not unparasitized species, exhibited a negative relationship between consistency and combinatorial distinctiveness. Moreover, regardless of parasitism status, consistency was negatively correlated with absolute distinctiveness across species. Together, these results suggest that (i) selection from parasites acts on how traits combine rather than absolute variation in traits, (ii) consistency and distinctiveness are alternative rather than complementary elements of signatures and (iii) mechanistic constraints may explain the negative relationship between consistency and absolute distinctiveness across species.Peer reviewe
APPLaUD: access for patients and participants to individual level uninterpreted genomic data.
BACKGROUND: There is a growing support for the stance that patients and research participants should have better and easier access to their raw (uninterpreted) genomic sequence data in both clinical and research contexts. MAIN BODY: We review legal frameworks and literature on the benefits, risks, and practical barriers of providing individuals access to their data. We also survey genomic sequencing initiatives that provide or plan to provide individual access. Many patients and research participants expect to be able to access their health and genomic data. Individuals have a legal right to access their genomic data in some countries and contexts. Moreover, increasing numbers of participatory research projects, direct-to-consumer genetic testing companies, and now major national sequencing initiatives grant individuals access to their genomic sequence data upon request. CONCLUSION: Drawing on current practice and regulatory analysis, we outline legal, ethical, and practical guidance for genomic sequencing initiatives seeking to offer interested patients and participants access to their raw genomic data
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