540 research outputs found
Wolbachia and Spiroplasma endosymbionts in the Anurida maritima (Collembola) species group
A large proportion of arthropods carry maternally-inherited endosymbiotic bacteria with which they have developed close relationships. Some of these endosymbionts are selfish genetic elements and manipulate their hosts’ reproduction to their own advantage, for example via cytoplasmic incompatibility (CI) or male killing. Here we report that the sexually reproducing collembolan Anurida maritima carries two endosymbionts (Wolbachia and Spiroplasma) and provide genome sequences for both bacteria. Phylogenomic analyses indicate that the Wolbachia belong to the A supergroup and that the Spiroplasma are sister to the Citri-Chrysopicola-Mirum lineage. A. maritima is considered a species group and consists of at least two distinct genetic lineages. We show that both lineages carry both endosymbionts. No homologs of the Spiroplasma male-killing gene SpAID were observed within our datasets. Homologs of the male-killing associated wmk and the CI inducing cifA and cifB prophage genes were detected in the Wolbachia genome. Phylogenetic analyses placed the cif genes in the poorly characterised Type V clade. The cifA and cifB gene sequences of the two Anurida lineages are identical. It therefore seems unlikely that the genetic divergence within the species group stems from cifA and cifB induced CI. Laboratory controlled genetic crosses and sex ratio studies will be needed to reveal any potential effect of the two endosymbionts on A. maritima’s reproduction
Black rabbits on Lundy: Tudor treasures or post-war phonies?
Lundy is renowned for its feral black rabbits which, according to popular tradition, have inhabited the island since medieval times. Black rabbit fur was valued for much of the Middle Ages, explaining why warreners of Lundy might have favoured them, but genes responsible for feral rabbit melanism remain unexplored. Further potential complicating factors occur in the form of recent (twentieth century) small-scale domestic rabbit introductions to the Lundy feral population. To gain insight into genetic mechanisms underlying melanism on Lundy, rabbit samples were collected and subjected to molecular analysis. The Lundy rabbit population is shown to harbour non-functional copies of the agouti signalling protein (Asip) gene, a main determinant of coat colour in mammals. The observed genetic mutation is not unique to Lundy, having been reported to underlie dark coat colour phenotypes in various domestic rabbit breeds. The mutation is recessive and only phenotypically expressed in homozygous individuals. Although presence of this particular allele does not preclude recent genetic augmentation or replacement, simple population genetics show that allele persistence from a medieval introduction is not impossible
Resisting antimicrobial resistance: lessons from fungus farming ants
Attine ants use antimicrobials produced by commensal bacteria to inhibit parasites on their fungal gardens. However, in this agricultural system, antimicrobial use does not lead to overwhelming resistance, as is typical in clinical settings. Mixtures of continually evolving antimicrobial variants could support these dynamics. [Abstract copyright: Copyright © 2019 Elsevier Ltd. All rights reserved.
Nature read in tooth and fur: non-invasive sampling of the Pygmy Shrew (Sorex minutus Linnaeus, 1766) on Lundy for population genetics
Britain’s smallest mammal, the pygmy shrew (Sorex minutus Linnaeus, 1766) is the only long established terrestrial mammal on Lundy. Little is known about this species’ mode of colonisation or its population structure on the island. Genetic analyses might provide useful insights in this respect, but DNA samples are difficult to obtain because pygmy shrews can be harmed by sampling methods. Two non invasive methods for obtaining DNA sequences were tested. DNA was extracted from hair samples and from a mandible derived from a bird-pellet. A 612 base pair fragment of the cytochrome oxidase b gene was PCR amplified and sequenced. To investigate the origin of pygmy shrew on Lundy the sequences were analysed in the context of published data. The sequences are most similar to those from the U.K. mainland which supports a British origin of this population
What's on the menu: Drosera rotundifolia diet determination using DNA data
The round-leaved sundew, Drosera rotundifolia, is a carnivorous plant species. On Lundy it is found in the nutrient-poor bog environments of Pondsbury and the northernmost quarry, where it supplements its diet with invertebrate prey. To gain insight into the diet of these two sundew populations a metabarcoding approach was trialled. This is, to our knowledge, the first study to use DNA barcodes to identify Drosera prey. At each site, a 0.25m2 quadrat was placed in a representative Drosera patch and two days’ worth of prey were collected. To identify prey items, Cytochrome c oxidase subunit I (COX1) sequences were obtained and compared to the Barcode of Life database. This revealed that Lundy sundews have a mixed diet. In total at least 20 different prey taxa were detected in the two 0.25m2 areas sampled. Sixteen taxa could be identified to species, indicating that metabarcoding permits accurate species level identification of sundew prey items. The majority of prey taxa were dipterans (two-winged flies), of which several have previously been reported on Lundy. Most prey taxa were detected in only one of the two quadrats examined (Jaccard’s index of Similarity=0.01; ‘dissimilar’). This might indicate that the two Drosera populations feed on distinct prey communities, but more research is needed to confirm this
Including People with Disabilities in Emergency Relief Efforts
The World Health Organization (WHO) estimates that around 15 per cent of the world’s population, or one billion people, have some form of disability. According to the United Nations Development Programme (UNDP), 80 per cent live in poor countries, where communities are already more vulnerable to disasters and crises such as the current Ebola epidemic, with people with disabilities often disproportionately affected. More must be done to ensure the needs and rights of people with disabilities are fully recognised in disaster risk reduction and emergency responses. Accelerating progress will require inclusive humanitarian programming and the use of technological solutions to be effectively promoted and incentivised, and people with disabilities and their organisations to be involved from the outset in the design and implementation of policies and programmes.UK Department for International Developmen
Research Report Executive Summary: Pre and Post Intervention Survey on Knowledge, Attitudes and Practices (KAP) on Disability and Inclusive Education in the Lakes Region, Kenya
Including Children with Disabilities in Primary School: the case of Mashonaland, Zimbabwe
This paper summarises the school-based information gathered on girls and boys with
disabilities in schools in four districts in Mashonaland West Province (MWP), a large
province in the north of Zimbabwe, as well as the main results derived from a survey
on knowledge, attitudes and practices of their parents or caregivers, teachers and
head teachers. This research forms part of a three-year project led by Leonard
Cheshire Disability Zimbabwe Trust to promote the provision of inclusive primary
education for children with disabilities in that province. The first part of the paper
outlines the current state of education for children with disabilities in 268 schools in
the four selected districts in MWP; including disaggregation of numbers of children in
school by age, gender and impairment. It also provides an overview of the numbers
of teachers as well as pupil/teacher ratios. The second part examines findings from a
survey on disability and Inclusive Education (IE), administered to 67 head teachers,
183 teachers and 186 parents/caregivers of children with disabilities.
Findings highlighted a lack of training in special education needs/IE, and the need for
further training emerges as a pressing issue. Overall, the attitudes and beliefs of
respondents were positive, but amongst the major perceived barriers preventing
children with disabilities from going to school by respondents was the lack of
assistive devices. Other major barriers include distance to school and lack of
transportation. Parents reported that the direct and indirect costs for schooling their
children with disabilities are too high. Head teachers and teachers identified human
resource allocation and financial administration as potential critical issues.
This survey contributes to the limited literature that examines knowledge, attitudes
and practices of teachers and families, as well as well as barriers and challenges
Research Brief: Pre and post-intervention comparative analysis - School level data and multi-informant survey knowledge, attitudes and practices (KAP) on disability and inclusive education
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