582 research outputs found

    Understanding species distribution in dynamic populations : a new approach using spatio‐temporal point process models

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    Funding: EU consolidator’s grant STATEMIG 310820 (SB).Understanding and predicting a species’ distribution across a landscape is of central importance in ecology, biogeography and conservation biology. However, it presents daunting challenges when populations are highly dynamic (i.e. increasing or decreasing their ranges), particularly for small populations where information about ecology and life history traits is lacking. Currently, many modelling approaches fail to distinguish whether a site is unoccupied because the available habitat is unsuitable or because a species expanding its range has not arrived at the site yet. As a result, habitat that is indeed suitable may appear unsuitable. To overcome some of these limitations, we use a statistical modelling approach based on spatio‐temporal log‐Gaussian Cox processes. These model the spatial distribution of the species across available habitat and how this distribution changes over time, relative to covariates. In addition, the model explicitly accounts for spatio‐temporal dynamics that are unaccounted for by covariates through a spatio‐temporal stochastic process. We illustrate the approach by predicting the distribution of a recently established population of Eurasian cranes Grus grus in England, UK, and estimate the effect of a reintroduction in the range expansion of the population. Our models show that wetland extent and perimeter‐to‐area ratio have a positive and negative effect, respectively, in crane colonisation probability. Moreover, we find that cranes are more likely to colonise areas near already occupied wetlands and that the colonisation process is progressing at a low rate. Finally, the reintroduction of cranes in SW England can be considered a human‐assisted long‐distance dispersal event that has increased the dispersal potential of the species along a longitudinal axis in S England. Spatio‐temporal log‐Gaussian Cox process models offer an excellent opportunity for the study of species where information on life history traits is lacking, since these are represented through the spatio‐temporal dynamics reflected in the model.PostprintPeer reviewe

    The risk of extinction for birds in Great Britain

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    t Over the last 20 years,species priorities for bird conservation in the UK have been guided by ‘Birds of Conservation Concern’ – an in-depth assessment made possible by the top-class data available on the status of the UK’s birds. For other wildlife, priorities tend to be informed by measures of extinction risk, generated by the IUCN Regional Red List process.We carried out the first formal IUCN assessment for birds in Great Britain. Of the 241 species assessed, 100 (43%) had at least one population (breeding and/or non-breeding) that qualified as Threatened using the standard IUCN Red List criteria and categories. Of 289 separate assessments of breeding or non-breeding populations, 39% qualified as Threatened (8% Critically Endangered, 14% Endangered, 17% Vulnerable) with a further 10% classified as Near Threatened. Both Golden Oriole Oriolus oriolus and Fieldfare Turdus pilaris were assessed as being Critically Endangered (Possibly Extinct) as breeding species, in addition to seven species that are already extinct (either Extinct or Regionally Extinct). The proportion of GB birds qualifying as Threatened was high compared with birds elsewhere in Europe and other taxonomic groups in GB. We believe that, if similar data were available, levels of extinction risk would be higher for other areas/taxa than is currently estimated

    Health-impaired employees' job satisfaction: new evidence from Athens, Greece

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    By utilizing the 2008 Athens Area Study (AAS) data set, this study investigates four aspects of job satisfaction - total pay, promotion prospects, respect received from one's supervisor, and total job satisfaction - between healthy and heath-impaired employees. Health impaired employees are found to be less satisfied according to all job satisfaction measures even when a large number of productivity features, and job characteristics are controlled for. The outcomes suggest also that women are more satisfied with their jobs than men are, regardless of health status. Moreover, the estimations show that health impaired employees' job satisfaction is affected more than healthy employees' job satisfaction by adverse mental health symptoms (life dissatisfaction). Finally, health impaired employees are found to become more satisfied with their jobs with time after disability onset. The study concludes that health impaired employees may have higher expectations about what they will obtain from their work, and that they may have job satisfaction adjustments

    Importance and Assessment of Quality of Life in Symptomatic Permanent Atrial Fibrillation: Patient Focus Groups from the RATE-AF Trial.

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    AIMS: To establish the extent and impact of symptoms in patients with atrial fibrillation (AF), the importance of different aspects of quality of life (QoL), and how we should assess wellbeing. METHODS: Focus groups of patients with symptomatic permanent AF in a trial of heart rate control; the RATE-AF trial randomised 160 patients aged ≥60 years with permanent AF and at least NYHA class II dyspnoea to either digoxin or beta-blockers. Patient and public representatives led the focus groups and performed all data acquisition and analysis, using thematic approaches to interpret patient views about QoL and its measurement. RESULTS: Substantial impairment of health-related QoL was noted in 160 trial patients, with impact on all domains apart from mental health. Eight women and 11 men aged 61-87 years participated in the focus groups. Common themes were a lack of information from healthcare professionals about AF, a lack of focus on QoL in consultations, and a sense of frustration, isolation, and reduced confidence. There was marked variability in symptoms in individual patients, with some describing severe impact on activities of daily living, and profound interaction with comorbidities such as arthritis. Day-to-day variation in QoL and difficulty in attributing symptom burden to AF or other comorbidities led to challenges in questionnaire completion. Consensus was reached that collecting both general and AF-specific QoL would be useful in routine practice, along with participation in peer support, which was empowering for the patients. CONCLUSIONS: The impact of comorbidities is poorly appreciated in the context of AF, with considerable variability in QoL that requires both generic and AF-specific assessment. Improvement in QoL should direct the appraisal, and reappraisal, of treatment decisions for patients with permanent AF

    Aboriginal young people’s perspectives and experiences of accessing sexual health services and sex education in Australia: A qualitative study

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    Aboriginal and Torres Strait Islander (Aboriginal) young people seek information and access health services for their sexual health needs. This study examined Aboriginal young people’s perspectives on sexual health services and sex education in Australia. Overall, 51 Aboriginal people aged 16–26 years were interviewed by peer researchers in Sydney, Australia in 2019–2020. The findings suggest that the internet was used to assess information quickly and confidentially, but Aboriginal young people questioned its reliability and accuracy. Family, Elders and peers were seen as sources of advice because they had real-life experience and highlighted intergenerational learning that occurs in Aboriginal communities. School-based sex education programmes had mixed reviews, with a preference for programmes delivered by external specialists providing anonymity, clear and accurate information about sex and relationships and positive approaches to sex education, including how to gain consent before sex. There was a need identified for school-based programmes to better consider the needs of Aboriginal young people, including those who identified as LGBTQI +. Aboriginal Medical Services were highly valued for providing culturally safe access to services, while sexual health clinics were valued for providing specialised confidential clinical services with low levels of judgement

    Ethanol production from xylose by pichia stipitis NRRL Y-7124 in a stirred tank bioreactor

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    The ethanol production by Pichia stipitis was evaluated in a stirred tank bioreactor using semidefined medium containing xylose (90.0 g/l) as the main carbon source. Experimental assays were performed according to a 22 full factorial design to evaluate the influence of aeration (0.25 to 0.75 vvm) and agitation (150 to 250 rpm) conditions on ethanol production. In the studied range of values, the agitation increase and aeration decrease favored ethanol production, which was maximum (26.7 g/l) using 250 rpm and 0.25 vvm, conditions that gave a volumetric oxygen transfer coefficient (kLa value) of 4.9 h-1. Under these conditions, the ethanol yield factor, ethanol productivity, and the process efficiency were 0.32 g/g, 0.32 g/l.h, and 63%, respectively. These results are promising and contribute to the development of a suitable process for ethanol production from xylose by Pichia stipitis.The authors gratefully acknowledge Santander, Fapesp, Capes, and CNPq (Brazil)
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