116 research outputs found

    The social structure and behaviour of Western Lowland gorillas (Gorilla gorilla gorilla) at Mbeli Bai, Republic of Congo

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    Most of what we know of the socioecology and behaviour of gorillas comes from studies of mountain gorillas (Gorilla beringei beringei), despite their representing less than 1% of all gorillas in the wild. Western lowland gorillas (Gorilla gorilla gorilla) have received far less research effort, and difficulties in habituation have led previous studies to rely heavily on indirect trail evidence. This has prevented any in-depth comparison of social structure and behaviour between species. The discovery of swampy clearings frequented by western lowland gorillas in northern Congo has offered the first opportunity to obtain accurate demographic and behavioural data. This thesis reports on 6273 hours of observer presence at Mbeli Bai, which yielded 1681 hours of direct gorilla observation. Most data come from a population of 13 groups and 7 solitary silverbacks. Group size ranged from 2 to 16 (mean = 8.4, SD 4.3) which does not differ significantly from data published on most other populations. Female natal and secondary transfer were recorded, and male emigration from the natal group appeared universal (no multi-silverback groups were recorded). No evidence of sub-grouping or a fission-fusion grouping pattern was found. During intra-group interactions, no evidence was recorded of female philopatry, and silverbacks herded and intimidated females (especially new immigrants) to prevent emigration. Inter-unit interactions took place on only 42% of shared bai-use occasions, and levels of silverback agonism were much lower than in mountain gorillas, with peaceful mingling of groups recorded. Display behaviour was common, and two previously unrecorded agonistic displays (the splash display and the crest display) are described. No contact aggression between silverbacks was observed but evidence of wounding sustained in the forest suggests that the bai environment may inhibit such aggression. High visibility and the ease of silverback 'policing' are thought to create an unusually tolerant social dynamic, and as such, frequencies of certain social behaviours should probably be viewed as site-specific. The thesis offers the fullest account of western gorilla social structure and behaviour to date. Long-term monitoring of life history variables, if continued, will provide an unparalleled opportunity to understand the effects of habitat and food availability and more stochastic influences on western gorilla social structure, fitness, and survival

    Satellite tracking highlights difficulties in the design of effective protected areas for Critically Endangered leatherback turtles Dermochelys coriacea during the inter-nesting period

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    The globally distributed leatherback turtle Der- mochelys coriacea is subject to fisheries bycatch throughout its range. Protection from fisheries within pelagic foraging habitats is difficult to achieve but may be more tractable when populations are concentrated near neritic breeding and nesting grounds. We used satellite telemetry to de- scribe patterns of habitat utilization during the inter- nesting period for seven leatherback turtles nesting at Mayumba National Park in Gabon on the equatorial West African coast. The National Park includes critical nesting grounds and a marine protected area to 15 km offshore. Turtles dispersed widely from the nesting beach spending a mean of 62 - SD 26% of tracking time outside the confines of the National Park. This propensity to disperse is likely to increase the chance of deleterious interactions with fisheries in the region. Patterns of habitat utilization indicate the need for wider spatial scale planning on the West African continental shelf to enhance protection of leatherback turtles when they are seasonally occupying these habitats in great numbers for breeding and nesting

    Seasonal feeding on bark by gorillas: an unexpected keystone food?

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    First paragraph: There are a number of reports in the literature of primates feeding on the bark of trees, but bark has only occasionally been considered as a major food to be studied in its own right (e.g., Waser, 1977; Beeson, 1987; Norris, 1988). All the great apes feed on bark at certain times, and clearly have preferences as to which species they choose (e.g., Schaller, 1963; Jones & Sabater Pi. 1971; Casimir, 1975: Nishida, 1976; Goodall, 1977; Rodman, 1977; Sabater Pi, 1977, 1979). Evidence has been presented that bark feeding by chimpanzees (Pan troglodytes) and orangutans (Pongo pygmaeus) is a seasonal phenomenon related to scarcity of preferred fruits (Nishida, 1976; Rodman, 1977), and similar conclusions have been drawn from studies of blue monkeys (Cercopithecus mitis) living near plantations of exotic pines (Beeson, 1987; Maganga & Wright, 1992). Bark feeding is also well known in other mammals where, again, it often occurs seasonally (e.g., elephants, Wing & Buss, 1970; grey squirrels, Kenward & Parish, 1986)

    Molecular weight dependent vertical composition profiles of PCDTBT:PC71BM blends for organic photovoltaics

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    We have used Soxhlet solvent purification to fractionate a broad molecular weight distribution of the polycarbazole polymer PCDTBT into three lower polydispersity molecular weight fractions. Organic photovoltaic devices were made using a blend of the fullerene acceptor PC71BM with the molecular weight fractions. An average power conversion efficiency of 5.89% (peak efficiency of 6.15%) was measured for PCDTBT blend devices with a number average molecular weight of Mn = 25.5 kDa. There was significant variation between the molecular weight fractions with low (Mn = 15.0 kDa) and high (Mn = 34.9 kDa) fractions producing devices with average efficiencies of 5.02% and 3.70% respectively. Neutron reflectivity measurements on these polymer:PC71BM blend layers showed that larger molecular weights leads to an increase in the polymer enrichment layer thickness at the anode interface, this improves efficiency up to a limiting point where the polymer solubility causes a reduction of the PCDTBT concentration in the active layer

    Optimising the impact of health services research on the organisation and delivery of health services : a mixed-methods study

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    The research reported in this issue of the journal was funded by the HSDR programme or one of its preceding programmes as project number 16/52/21.Background The limitations of ‘knowledge transfer’ are increasingly recognised, with growing interest in ‘knowledge co-production in context’. One way of achieving the latter is by ‘embedding’ researchers in health service settings, yet how to deliver such schemes successfully is poorly understood. Objectives The objectives were to examine the nature of ‘embedded knowledge co-production’ and explore how embedded research initiatives can be designed more effectively. Design The study used four linked workstreams. Workstream 1 involved two parallel literature reviews to examine how ‘knowledge co-production’ and ‘embedded research’ are conceptualised, operationalised and discussed. In workstream 2, a scoping review of exisiting or recent ‘embedded researcher’ schemes in UK health settings was carried out. Workstream 3 involved developing four in-depth case studies on such schemes to understand their mechanisms, effectiveness and challenges. In workstream 4, insights from the other workstreams were used to provide recommendations, guidance and templates for the different ways embedded co-production may be framed and specified. The overall goal was to help those interested in developing and using such approaches to understand and address the design choices they face. Setting Embedded research initiatives in UK health settings. Data sources Data were sourced from the following: analysis of the published and grey literature (87 source articles on knowledge co-production, and 47 published reports on extant embedded research initiatives), documentation and interviews with key actors across 45 established embedded research initiatives, in-depth interviews and site observations with 31 participants over 12 months in four intensive case studies, and informal and creative engagement in workshops (n = 2) and with participants in embedded research initiatives who joined various managed discussion forums. Participants The participants were stakeholders and participants in embedded research initiatives. Results The literature reviews from workstream 1 produced practical frameworks for understanding knowledge co-production and embedded research initiatives, which, with the scoping review (workstream 2), informed the identification and articulation of 10 design concerns under three overarching categories: intent (covering outcomes and power dynamics), structures (scale, involvement, proximity and belonging) and processes (the functional activities, skills and expertise required, nature of the relational roles, and the learning mechanisms employed). Current instances of embedded research were diverse across many of these domains. The four case studies (workstream 3) added insights into scheme dynamics and life cycles, deepening understanding of the overarching categories and showing the contingencies experienced in co-producing knowledge. A key finding is that there was often a greater emphasis on embeddedness per se than on co-production, which can be hard to discern. Finally, the engaging and influencing activities running throughout (workstream 4) allowed these research-rooted insights to be translated into practical tools and resources, evidenced by peer-reviewed publications, for those interested in exploring and developing the approach. Conclusions Embedded research has a strong underpinning rationale, and more is becoming known about its design and management challenges. The tools and resources developed in this project provide a coherent evidence-informed framework for designing, operationalising and managing such schemes. It cannot yet be said with clarity that the potential benefits of embedded research are always deliverable, nor what the cost would be. Future work With the means to describe and categorise different types of embedded research initiatives, more evaluative work is now needed to examine the relative merits and costs of different designs. Funding This project was funded by the National Institute for Health Research (NIHR) Health and Social Care Delivery Research programme and will be published in full in Health and Social Care Delivery Research; Vol. 10, No. 3. See the NIHR Journals Library website for further project information.Publisher PDFPeer reviewe

    Detection of reduced carbon in a basalt analogue for martian nakhlite : a signpost to habitat on Mars

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    C. W. Taylor and J. Still are thanked for skilled technical support. J. Parnell, H.G.M. Edwards, I. Hutchinson and R. Ingley acknowledge the support of the UKSA and the STFC Research Council in the UK ExoMars programme. L. V. Harris and S. McMahon acknowledge STFC studentship funding.Peer reviewedPublisher PD

    Addressing uncertainty in marine resource management; combining community engagement and tracking technology to characterize human behavior

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    This study was approved by the University of Exeter Ethics committee and the Ministry of Scientific Research and Technological Innovation in Congo (Permit: No. 023/MRSIT/DGRST/DMAST); and supported by funding from the Darwin Initiative (Projects 20-009 and 23-011) and the Wildlife Conservation Society.Small-scale fisheries provide an essential source of food and employment for coastal communities, yet the availability of detailed information on the spatiotemporal distribution of fishing effort to support resource management at a country level is scarce. Here, using a national-scale study in the Republic of Congo, we engaged with fishers from 23 of 28 small-scale fisheries landing sites along the coast to demonstrate how combining community engagement and relatively low cost Global Positioning System (GPS) trackers can rapidly provide fine-scale information on: (1) the behavioral dynamics of the fishers and fleets that operate within this sector; and (2) the location, size and attributes of important fishing grounds upon which communities are dependent. This multi-disciplinary approach should be considered within a global context where uncertainty over the behavior of marine and terrestrial resource-users can lead to management decisions that potentially compromise local livelihoods, conservation, and resource sustainability goals.Publisher PDFPeer reviewe

    Sensitivity of fluvial sediment source apportionment to mixing model assumptions: A Bayesian model comparison

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    Mixing models have become increasingly common tools for apportioning fluvial sediment load to various sediment sources across catchments using a wide variety of Bayesian and frequentist modeling approaches. In this study, we demonstrate how different model setups can impact upon resulting source apportionment estimates in a Bayesian framework via a one-factor-at-a-time (OFAT) sensitivity analysis. We formulate 13 versions of a mixing model, each with different error assumptions and model structural choices, and apply them to sediment geochemistry data from the River Blackwater, Norfolk, UK, to apportion suspended particulate matter (SPM) contributions from three sources (arable topsoils, road verges, and subsurface material) under base flow conditions between August 2012 and August 2013. Whilst all 13 models estimate subsurface sources to be the largest contributor of SPM (median ∼76%), comparison of apportionment estimates reveal varying degrees of sensitivity to changing priors, inclusion of covariance terms, incorporation of time-variant distributions, and methods of proportion characterization. We also demonstrate differences in apportionment results between a full and an empirical Bayesian setup, and between a Bayesian and a frequentist optimization approach. This OFAT sensitivity analysis reveals that mixing model structural choices and error assumptions can significantly impact upon sediment source apportionment results, with estimated median contributions in this study varying by up to 21% between model versions. Users of mixing models are therefore strongly advised to carefully consider and justify their choice of model structure prior to conducting sediment source apportionment investigations

    Facile Control over the Supramolecular Ordering of Self-assembled Peptide Scaffolds by Simultaneous Assembly with a Polysacharride

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    Enabling control over macromolecular ordering and the spatial distribution of structures formed via the mechanisms of molecular self-assembly is a challenge that could yield a range of new functional materials. In particular, using the self-assembly of minimalist peptides, to drive the incorporation of large complex molecules will allow a functionalization strategy for the next generation of biomaterial engineering. Here, for the first time, we show that co-assembly with increasing concentrations of a highly charged polysaccharide, fucoidan, the microscale ordering of Fmoc-FRGDF peptide fibrils and subsequent mechanical properties of the resultant hydrogel can be easily and effectively manipulated without disruption to the nanofibrillar structure of the assemblyThis work was supported by an Australian Research Council Discovery Project grant, DP130103131. RJW was supported by an Alfred Deakin Research Fellowship, DRN was supported by an NHMRC career development fellowship. The SANS beamtime was provided by the Institut Laue-Langevin (ILL) andaccess funded by the Science and Technology Facilities Council STFC (UK) doi:10.5291/ILL-DATA.8-03-840. Financial support from the BMBF Project No. 05K13KT1 is gratefully acknowledged
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