304 research outputs found

    Interactions between pygmy bluetongue lizards and co-existing species

    Get PDF
    This is an Accepted Manuscript of an article published by Taylor & Francis in TRANSACTIONS OF THE ROYAL SOCIETY OF SOUTH AUSTRALIA on 14 June 2015, available online: http://www.tandfonline.com/10.1080/03721426.2015.1051644. This author version will be under embargo for a period of 12 months from the date of publicationThis paper describes observations of interactions between endangered pygmy bluetongue lizards (Tiliqua adelaidensis) and other species that co-occur in their native grassland habitat in the mid-north region of South Australia. The lizard lives in spider burrows, and rarely moves away from the burrow entrance. We viewed over 16,000 h of video recording of occupied pygmy bluetongue lizard burrows, taken over five 10 day periods throughout one complete lizard activity season, and documented all cases in which these endangered lizards interacted with co-existing species. We found that these interactions were infrequent. We observed potential competition over burrow resources with lycosid spiders (Lycosa spp), centipedes, and a house mouse, and potential competition over invertebrate prey with a predatory wasp. We also observed unsuccessful predation attempts on lizards in burrows by ravens and brown snakes. We suggest that conservation management might have proceeded effectively without this information, but that it provides useful background information for informed decision making

    Testing the robustness of transmission network models to predict ectoparasite loads. One lizard, two ticks and four years

    Get PDF
    Open access under CC BY-NC-SA licenseAbstract We investigated transmission pathways for two tick species, Bothriocroton hydrosauri and Amblyomma limbatum, among their sleepy lizard (Tiliqua rugosa) hosts in a natural population in South Australia. Our aim was to determine whether a transmission network model continued to predict parasite load patterns effectively under varying ecological conditions. Using GPS loggers we identified the refuge sites used by each lizard on each day. We estimated infectious time windows for ticks that detached from a lizard in a refuge. Time windows were from the time when a detached tick molted and become infective, until the time it died from desiccation while waiting for a new host. Previous research has shown that A. limbatum molts earlier and survives longer than B. hydrosauri. We developed two transmission network models based on these differences in infective time windows for the two tick species. Directed edges were generated in the network if one lizard used a refuge that had previously been used by another lizard within the infectious time window. We used those models to generate values of network node in-strength for each lizard, a measure of how strongly connected an individual is to other lizards in the transmission network, and a prediction of infection risk for each host. The consistent correlations over time between B. hydrosauri infection intensity and network derived infection risk suggest that network models can be robust to environmental variation among years. However, the contrasting lack of consistent correlation in A. limbatum suggests that the utility of the same network models may depend on the specific biology of a parasite species

    A good place to raise a family? Comparing parents, service-providers\u27, and media perspectives of the inner and outer suburban areas of Melbourne

    Full text link
    In Australia, the suburbs have historically been the favoured place to raise children. However this is being challenged both by social change and government policy encouraging innerurban renewal. We examined how inner-urban areas compare with more traditional suburban locations as places to raise a family. Recognising that there are many influences on perceptions of place, we included the opinions of parents, service-providers and the media in the two locations.Research focused on two municipalities in Melbourne, one located >25km and the other <10km from the CBD. Themes were obtained and compared from in-depth interviews with parents, serviceproviders and analysis of municipality-specific and state-wide newspaper articles.Service provision was the only theme common at all levels of analysis. For all other themes, differences occurred between perspectives of service-providers, media and parents, as well as between the two residential locations. These in-depth snapshots on the challenges and rewards of raising children in different urban locations can help inform government in planning healthy neighbourhoods that better serve the needs of contemporary Australian families

    Structure and diversity of fish communities in man-made ponds of the Niger Delta (southern Nigeria)

    Get PDF
    1. A survey of eight local earthen hand-dug ponds located within the freshwater swamps of a Niger Delta area (southern Nigeria) was conducted over a period of 3 months. A total of 4,313 fishes representing 19 species from 12 families were recorded.2. The most abundant species was Xenomystus nigri (905 individuals), whereas the least common was Protopterus annectens (13). Cichlidae and Clariidae counted three species each, whereas Anabantidae, Hepsetidae, Mochokidae, Protopteridae, Phractolaemidae, Malapteruridae and Gymnarchidae were represented by a single species each.3. A lotic species, Synodontis sp., was recorded possibly as a result of the episodic flood of 2012.4. The Engenni swamps harbour a moderately diverse ichthyofauna. Regulations should be put in place to further enhance the fisheries potential of these local ponds

    "Most of what they do, we cannot do!" How lay health workers respond to barriers to uptake and retention in HIV care among pregnant and breastfeeding mothers in Malawi

    Get PDF
    Background: In the era of Option B+ and 'treat all' policies for HIV, challenges to retention in care are well documented. In Malawi, several large community-facility linkage (CFL) models have emerged to address these challenges, training lay health workers (LHW) to support the national prevention of mother-to-child transmission (PMTCT) programme. This qualitative study sought to examine how PMTCT LHW deployed by Malawi's three most prevalent CFL models respond to known barriers to access and retention to antiretroviral therapy (ART) and PMTCT. Methods: We conducted a qualitative study, including 43 semi-structured interviews with PMTCT clients; 30 focus group discussions with Ministry of Health (MOH)-employed lay and professional providers and PMTCT LHWs; a facility CFL survey and 2–4 hours of onsite observation at each of 8 sites and in-depth interviews with 13 programme coordinators and MOH officials. Thematic analysis was used, combining inductive and deductive approaches. Results: Across all three models, PMTCT LHWs carried out a number of 'targeted' activities that respond directly to a range of known barriers to ART uptake and retention. These include: (i) fulfilling counselling and educational functions that responded to women's fears and uncertainties; (ii) enhancing women's social connectedness and participation in their own care and (iii) strengthening service function by helping clinic-based providers carry out duties more efficiently and effectively. Beyond absorbing workload or improving efficiency, however, PMTCT LHWs supported uptake and retention through foundational but often intangible work to strengthen CFL, including via efforts to strengthen facility-side responsiveness, and build community members' recognition of and trust in services. Conclusion: PMTCT LHWs in each of the CFL models examined, addressed social, cultural and health system factors influencing client access to, and engagement with, HIV care and treatment. Findings underscore the importance of person-centred design in the 'treat-all' era and the contribution LHWs can make to this, but foreground the challenges of achieving person-centredness in the context of an under-resourced health system. Further work to understand the governance and sustainability of these project-funded CFL models and LHW cadres is now urgently required

    A computational fluid dynamics study of flared gas for enhanced oil recovery using a micromodel

    Get PDF
    The current handling of gas associated with oil production poses an environmental risk. This gas is being flared off due to the technical and economic attractiveness of this option. As flared gases are mainly composed of methane, they have harmful greenhouse effects when released into the atmosphere. This work discusses the effectiveness of using this gas for enhanced oil recovery (EOR) purposes as an alternative to flaring. In this study, a micromodel was designed with properties similar to a sandstone rock with a porosity of 0.4, and computational fluid dynamics (CFD) techniques were applied to design an EOR system. Temperature effects were not considered in the study, and the simulation was run at atmospheric pressure. Five case studies were carried out with different interfacial tensions between the oil and gas (0.005 N/m, 0.017 N/m, and 0.034 N/m) and different injection rates for the gas (1 × 10−3 m/s, 1 × 10−4 m/s, and 1 × 10−6 m/s). The model was compared with a laboratory experiment measuring immiscible gas flooding. Factors affecting oil recoveries, such as the interfacial tension between oil and gas, the viscosity, and the pressure, were studied in detail. The results showed that the surface tension between the oil and gas interphase was a limiting factor for maximum oil recovery. The lower surface tension recovered 33% of the original oil in place. The capillary pressure was higher than the pressure in the micromodel, which lowered the amount of oil that was displaced. The study showed the importance of pressure maintenance to increase oil recovery for immiscible gas floods. It is recommended that a wider set of interfacial tensions between oil and gas be tested to obtain a range at which oil recovery is maximum for EOR with flared gas

    Viral clearance considerations for continuous viral inactivation

    Get PDF
    Continuous low pH viral inactivation has been considered by Boehringer Ingelheim, Pfizer, and other companies who are investing in integrated processing. In continuous viral inactivation, a critical parameter that poses a new challenge is the exact incubation time of the product stream. In a continuous space, the concept of time translates in the product flow rate, incubation volume, and dispersion effects. To address dispersion, we define the minimum residence time, tmin, as the time when the first product element exits the tubular chamber. In this work, we characterize the tmin for a novel, scalable, and sturdy tubular reactor design that can serve as an incubation chamber for a process capable to produce \u3e1kg of product. In addition, we provide robust data for a scale down model suitable for viral studies. We propose an innovative in-line spiking methodology to validate the minimum residence time using viruses. This methodology can be used as a viral clearance platform for continuous low pH virus inactivation. Finally, we propose a trace response method to be used as a way to verify that the process was properly set up

    Community and health system intervention to reduce disrespect and abuse during childbirth in Tanga Region, Tanzania: A comparative before-and-after study

    Get PDF
    Background Abusive treatment of women during childbirth has been documented in low-resource countries and is a deterrent to facility utilization for delivery. Evidence for interventions to address women’s poor experience is scant. We assessed a participatory community and health system intervention to reduce the prevalence of disrespect and abuse during childbirth in Tanzania. Methods and findings We used a comparative before-and-after evaluation design to test the combined intervention to reduce disrespect and abuse. Two hospitals in Tanga Region, Tanzania were included in the study, 1 randomly assigned to receive the intervention. Women who delivered at the study facilities were eligible to participate and were recruited upon discharge. Surveys were conducted at baseline (December 2011 through May 2012) and after the intervention (March through September 2015). The intervention consisted of a client service charter and a facility-based, quality-improvement process aimed to redefine norms and practices for respectful maternity care. The primary outcome was any self-reported experiences of disrespect and abuse during childbirth. We used multivariable logistic regression to estimate a difference-in-difference model. At baseline, 2,085 women at the 2 study hospitals who had been discharged from the maternity ward after delivery were invited to participate in the survey. Of these, 1,388 (66.57%) agreed to participate. At endline, 1,680 women participated in the survey (72.29% of those approached). The intervention was associated with a 66% reduced odds of a woman experiencing disrespect and abuse during childbirth (odds ratio [OR]: 0.34, 95% CI: 0.21–0.58, p < 0.0001). The biggest reductions were for physical abuse (OR: 0.22, 95% CI: 0.05–0.97, p = 0.045) and neglect (OR: 0.36, 95% CI: 0.19–0.71, p = 0.003). The study involved only 2 hospitals in Tanzania and is thus a proof-of-concept study. Future, larger-scale research should be undertaken to evaluate the applicability of this approach to other settings. Conclusions After implementation of the combined intervention, the likelihood of women’s reports of disrespectful treatment during childbirth was substantially reduced. These results were observed nearly 1 year after the end of the project’s facilitation of implementation, indicating the potential for sustainability. The results indicate that a participatory community and health system intervention designed to tackle disrespect and abuse by changing the norms and standards of care is a potential strategy to improve the treatment of women during childbirth at health facilities. The trial is registered on the ISRCTN Registry, ISRCTN 48258486

    Introducing a drift and diffusion framework for childhood growth research

    Get PDF
    Acknowledgements We thank the participants and staff of the MAL-ED study for their vital contributions and we thank Prof. Laura Caulfield for her insightful and constructive input. The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the U.S. National Institutes of Health or Department of Health and Human Services. Publisher Copyright: © 2020 Lewis FI et al.Peer reviewedPublisher PD
    corecore