1,692 research outputs found
Higher sociability leads to lower reproductive success in female kangaroos: Sociability and fitness in kangaroos
In social mammals, social integration is generally assumed
to improve females’ reproductive success. Most species
demonstrating this relationship exhibit complex forms of social
bonds and interactions. However, female eastern grey kangaroos
(Macropus giganteus) exhibit differentiated social relationships,
yet do not appear to cooperate directly. It is unclear what the
fitness consequences of such sociability could be in species that
do not exhibit obvious forms of cooperation. Using 4 years of
life history, spatial and social data from a wild population of
approximately 200 individually recognizable female eastern
grey kangaroos, we tested whether higher levels of sociability
are associated with greater reproductive success. Contrary to
expectations, we found that the size of a female’s social
network, her numbers of preferential associations with other
females and her group sizes all negatively influenced her
reproductive success. These factors influenced the survival of
dependent young that had left the pouch rather than those that
were still in the pouch. We also show that primiparous females
(first-time breeders) were less likely to have surviving young.
Our findings suggest that social bonds are not always beneficial
for reproductive success in group-living species, and that female
kangaroos may experience trade-offs between successfully
rearing young and maintaining affiliative relationships
Higher sociability leads to lower reproductive success in female kangaroos
In social mammals, social integration is generally assumed to improve females' reproductive success. Most species demonstrating this relationship exhibit complex forms of social bonds and interactions. However, female eastern grey kangaroos (Macropus giganteus) exhibit differentiated social relationships, yet do not appear to cooperate directly. It is unclear what the fitness consequences of such sociability could be in species that do not exhibit obvious forms of cooperation. Using 4 years of life history, spatial and social data from a wild population of approximately 200 individually recognizable female eastern grey kangaroos, we tested whether higher levels of sociability are associated with greater reproductive success. Contrary to expectations, we found that the size of a female's social network, her numbers of preferential associations with other females and her group sizes all negatively influenced her reproductive success. These factors influenced the survival of dependent young that had left the pouch rather than those that were still in the pouch. We also show that primiparous females (first-time breeders) were less likely to have surviving young. Our findings suggest that social bonds are not always beneficial for reproductive success in group-living species, and that female kangaroos may experience trade-offs between successfully rearing young and maintaining affiliative relationships
Scanning electron microscopy and energy-dispersive x-ray spectroscopy (SEM-EDX) confirms shooting of a hen harrier (Circus cyaneus)
The hen harrier (Circus cyaneus) remains severely restricted as a breeding species in England despite sufficient habitat for over 300 breeding pairs. Human persecution is the main limiting factor and in the UK, there have been 45 confirmed incidents of shooting of hen harriers since records began (Royal Society for the Protection of Birds unpublished data). The authors report the pathological examination of a hen harrier, the detection of suspected ballistic fragments by radiograph and explain how scanning electron microscopy and energy-dispersive x-ray spectroscopy (SEM-EDX) was used to confirm (i) the composition of one ballistic remnant and (ii) that the remnant had been projected into and had damaged the bone. The authors report the use of post-analysis software to discriminate apparent anomalies produced by the proprietary SEM-EDX software package and discuss broader uses of SEM-EDX for wildlife crime investigation
Vandetanib-eluting radiopaque beads for chemoembolization: physicochemical evaluation and biological activity of vandetanib in hypoxia.
Vandetanib-eluting radiopaque beads (VERB) have been developed for use in transarterial chemoembolization of liver tumours, with the goal of combining embolization with local delivery of antiangiogenic therapy. The objective of this study was to investigate how embolization-induced hypoxia may affect antitumoural activity of vandetanib, an inhibitor of vascular endothelial growth factor receptor (VEGFR) and epidermal growth factor receptor (EGFR), in the context of hepatocellular carcinoma (HCC) treatment. We studied the effect of vandetanib on proliferation, cell cycle and apoptosis of HCC cells, in hypoxic conditions, as well as the direct effects of the beads on 3D HCC spheroids. Vandetanib suppressed proliferation and induced apoptosis of HCC cells in vitro and was equipotent in hypoxic and normoxic conditions. High degrees of apoptosis were observed among cell lines in which vandetanib suppressed ERK1/2 phosphorylation and upregulated the proapoptotic protein Bim, but this did not appear essential for vandetanib-induced cell death in all cell lines. Vandetanib also suppressed the hypoxia-induced secretion of VEGF from HCC cells and inhibited proliferation of endothelial cells. Incubation of tumour spheroids with VERB led to sustained growth inhibition equivalent to the effect of free drug. We conclude that vandetanib has both antiangiogenic and direct anticancer activity against HCC cells even in hypoxic conditions, warranting the further evaluation of VERB as novel anticancer agents
Opening up, closing down, or leaving ajar? How applications are used in engaging with publics about gene drive
This is the final version. Available from Taylor & Francis via the DOI in this record. Public engagement and responsible innovation are strongly emphasised in gene drive research, together with the goal of addressing societal challenges, notably, malaria and environmental conservation. We aim to explore whether public engagement is used to ‘open up' or ‘close down' opportunities to shape gene drive research. Drawing on interviews with gene drive developers and stakeholders, we investigate how the public communication of gene drive is conceived. We find that traditional closing-down tendencies remain, but that there are new and encouraging opening-up approaches. Consistent with responsible innovation thinking, these frame gene drive as multifaceted, context-dependent and requiring deeper deliberation. We also identify a third ‘leaving ajar’ approach that seeks to engage with and respond to local communities and modify technological applications to be more acceptable. Innovation system constraints may well temper current aspirations to open up; framing public conversations around understandings of public good could offer a way forward.Wellcome TrustCSIR
A rocky planet transiting a nearby low-mass star
M-dwarf stars -- hydrogen-burning stars that are smaller than 60 per cent of
the size of the Sun -- are the most common class of star in our Galaxy and
outnumber Sun-like stars by a ratio of 12:1. Recent results have shown that M
dwarfs host Earth-sized planets in great numbers: the average number of M-dwarf
planets that are between 0.5 to 1.5 times the size of Earth is at least 1.4 per
star. The nearest such planets known to transit their star are 39 parsecs away,
too distant for detailed follow-up observations to measure the planetary masses
or to study their atmospheres. Here we report observations of GJ 1132b, a
planet with a size of 1.2 Earth radii that is transiting a small star 12
parsecs away. Our Doppler mass measurement of GJ 1132b yields a density
consistent with an Earth-like bulk composition, similar to the compositions of
the six known exoplanets with masses less than six times that of the Earth and
precisely measured densities. Receiving 19 times more stellar radiation than
the Earth, the planet is too hot to be habitable but is cool enough to support
a substantial atmosphere, one that has probably been considerably depleted of
hydrogen. Because the host star is nearby and only 21 per cent the radius of
the Sun, existing and upcoming telescopes will be able to observe the
composition and dynamics of the planetary atmosphere.Comment: Published in Nature on 12 November 2015, available at
http://dx.doi.org/10.1038/nature15762. This is the authors' version of the
manuscrip
What are the requirements for developing a successful national registry of auditory implants? A qualitative study
OBJECTIVES: Hearing loss is an area of unmet need, and industry is targeting this field with a growing range of surgically implanted hearing devices. Currently, there is no comprehensive UK registry capturing data on these devices; in its absence, it is difficult to monitor clinical and cost-effectiveness and develop national policy. Recognising that developing such a registry faces considerable challenges, it is important to gather opinions from stakeholders and patients. This paper builds on our systematic review on surgical registry development and aims to identify the specific requirements for developing a successful national registry of auditory implants. DESIGN: Qualitative study. PARTICIPANTS: Data were collected in two ways: (1) semistructured interviews with UK professional stakeholders; and (2) focus groups with patients with hearing loss. The interview and focus group schedules were informed by our systematic review on registry development. Data were analysed using directed content analysis. Judges mapped the themes obtained against a conceptual framework developed from our systematic review on registry development. The conceptual framework consisted of five categories for successful registry development: (1) planning, (2) registry governance, (3) registry dataset, (4) anticipating challenges, (5) implementing solutions. RESULTS: Twenty-seven themes emerged from 40 semistructured interviews with professional stakeholders and 18 themes emerged from three patient focus groups. The most important factor for registry success was high rates of data completion. Benefits of developing a successful registry of auditory implants include: strengthening the evidence base and regulation of auditory implants, driving quality and safety improvements, increased transparency, facilitating patient decision-making and informing policy and guidelines development. CONCLUSIONS: This study identifies the requirements for developing a successful national registry of auditory implants, benefiting from the involvement of numerous professional stakeholder groups and patients with hearing loss. Our approach may be used internationally to inform successful registry development
Poisoning of reintroduced red kites (Milvus Milvus) in England
Programmes to reintroduce predatory birds are resource intensive and expensive, yet there are few long-term studies on the health of these reintroduced birds following release. A total of 326 red kites (Milvus milvus) were released at four sites in England between 1989 and 2006 as part of efforts to reintroduce this species to England and Scotland, resulting in the establishment of several rapidly expanding populations in the wild. Detailed post-mortem examinations were carried out on 162 individuals found dead between 1989 and 2007, involving both released and wild-fledged birds. Toxicological analysis of one or more compounds was performed on 110 of the 162 birds. Poisoning was diagnosed in 32 of these 110 kites, 19 from second generation anticoagulant rodenticides, 9 from other pesticides and six from lead. Criteria for diagnosing anticoagulant rodenticide poisoning included visible haemorrhage on gross post-mortem examination and levels of anticoagulant rodenticide exceeding 100 ng/g, but levels were elevated above 100 ng/g in a further eight red kites without visible haemorrhages, suggesting poisoning may have occurred in more birds. The anticoagulant rodenticides difenacoum and bromadiolone were the most common vertebrate control agents involved during this period. Poisoning of red kites may be slowing their rate of population recovery and range expansion in England. Simple modifications of human activity, such as best practice in rodent control campaigns, tackling the illegal use of pesticides and the use of non-toxic alternatives to lead ammunition, can reduce our impact on red kites and probably other populations of predatory and scavenging species
Volunteer trials of a novel improvised dry decontamination protocol for use during mass casualty incidents as part of the UK’S Initial Operational Response (IOR)
Copyright: © 2017 Amloˆt et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Previous studies have demonstrated that rapid evacuation, disrobing and emergency decontamination can enhance the ability of emergency services and acute hospitals to effectively manage chemically-contaminated casualties. The purpose of this human volunteer study was to further optimise such an “Initial Operational Response” by (1) identifying an appropriate method for performing improvised skin decontamination and (2) providing guidance for use by first responders and casualties. The study was performed using two readily available, absorbent materials (paper towels and incontinence pads). The decontamination effectiveness of the test materials was measured by quantifying the amount of a chemical warfare agent simulant (methyl salicylate) removed from each volunteer’s forearm skin. Results from the first study demonstrated that simulant recovery was lower in all of the dry decontamination conditions when compared to matched controls, suggesting that dry decontamination serves to reduce chemical exposure. Blotting in combination with rubbing was the most effective form of decontamination. There was no difference in effectiveness between the two absorbent materials. In the following study, volunteers performed improvised dry decontamination, either with or without draft guidelines. Volunteers who received the guidance were able to carry out improvised dry decontamination more effectively, using more of the absorbent product (blue roll) to ensure that all areas of the body were decontaminated and avoiding cross-contamination of other body areas by working systematically from the head downwards. Collectively, these two studies suggest that absorbent products that are available on ambulances and in acute healthcare settings may have generic applicability for improvised dry decontamination. Wherever possible, emergency responders and healthcare workers should guide casualties through decontamination steps; in the absence of explicit guidance and instructions, improvised dry decontamination may not be performed correctly or safely.Peer reviewedFinal Published versio
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