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Many tasks in midwifery are learned and taught from a right-handed perspective, meaning they may prove difficult for people who are lefthanded. Experiences of midwives and midwifery students show that there are various barriers to learning and performing certain skills for left-handed people, and they are often forced to choose whether to persist in conforming to the 'norm' and using their right hand, or adapt elements of practice to suit left-hand dominance. [ABSTRACT FROM AUTHOR]

In forest communities, the Janzen-Connell (J-C) hypothesis proposes that species diversity is maintained by non-competitive distance- and/or density-dependent seedling mortality caused by host-specific natural enemies. However, the effects of pathogen associations from nearby conspecifics versus heterospecifics remain unknown in spatially heterogeneous light environments., Seeds of hardwood species Cornus controversa ( Cornus) and Prunus grayana ( Prunus) were sown beneath 6-7 Cornus and Prunus adults in both the forest understory ( FU) and in gaps (Gap) created by felling all woody vegetation near the focal adults. Seedling growth, mortality, killing agents (e.g. pathogens that cause damping-off and leaf diseases), and root infection by arbuscular mycorrhizal fungi ( AMF) were investigated., We found strong habitat effects on the expression of soil fungi beneath both tree species. Seedling mortality caused by soil-borne damping-off pathogens was greater in FU than in Gap, and AMF infection, which enhanced relative seedling growth rate, was greater in Gap than in FU. Seedling mortality caused by damping-off pathogens did not differ between Cornus and Prunus seedlings beneath the adults of conspecific or heterospecific adults in both FU and Gap, suggesting little distance-dependence or host preference in the fungus., Beneath the adults of Cornus and Prunus, the most prevalent leaf diseases were zonate leaf blight and angular leaf spot caused by the airborne pathogenic fungi Haradamyces foliicola and Phaeoisariopsis pruni-grayanae, respectively. Although these pathogens attacked the seedlings of both species, conspecific seedlings (i.e. home) showed more severe leaf damage, earlier leaf shedding and/or less defensive behaviour (cell wall defence) relative to heterospecific seedlings (i.e. away), suggesting negative distance-dependent attack (i.e. host preference) for these leaf diseases. As a result, greater seedling mortality was observed for conspecific seedlings under both FU and Gap treatments., Synthesis. In the temperate forest, the J-C hypothesis is largely mediated through the strong negative influence of airborne leaf diseases rather than through soil-borne damping-off pathogens. We found that airborne diseases demonstrated distance-dependent host preferences, which led to greater conspecific seedling damage regardless of environmental light conditions. [ABSTRACT FROM AUTHOR]

Current midwifery practice is regulated by the Nursing and Midwifery Council (NMC), whose primary role is to safeguard the public through setting standards for education and practice and regulating fitness to practise, conduct and performance through rules and codes (NMC, 2012; 2015a). Practice is informed by evidence-based guidelines developed and implemented by the National Institute for Health and Care Excellence based on hierarchies of evidence, with meta-analyses and systematic reviews being identified as the 'gold standard'. This positivist epistemological approach as developed by Auguste Comte (1798-1857), with scientific evidence at the top of a knowledge hierarchy, fails to acknowledge the 'art of midwifery', where a constructivist paradigm of experiential, intuitive and tacit knowledge is used by reflective practitioners to provide high-quality care. As midwifery pre-registration education is now degree-level, is the essence of midwifery practice being 'with woman' providing holistic care under threat, as the drive for a systematic and analytical approach to decision-making gathers momentum? [ABSTRACT FROM AUTHOR]

A personal narrative is presented which explores the author's approach in writing for the "British Journal of Midwifery."

In the study of insect-vectored plant viruses, colonizing vector species remain the focus. However, non-colonizing vector species, those that do not settle and reproduce on the viral plant host, are often the most abundant in the field and may be the largest contributors to disease spread. While non-colonists may have a substantial effect on disease prevalence, the factors influencing their movement and transmission on non-host plants have been little studied. Here we evaluated how a common biological control agent ( Hippodamia convergens), host and non-host plant abundance, and plant spatial distribution impact the movement and density of a wingless non-colonizing vector [ Rhopalosiphum padi (L.)] and transmission of potato virus Y (PVY) in potatoes in experimental arenas. The results of this work illustrate the importance of plant species function (host or non-host) and distribution to vector behavior and disease spread. Predation, host plant abundance, and plant spatial distribution interactively affected viral prevalence within infected arenas. Increasing the number of vector non-host plants increased the distance and frequency of aphid movement, and the effect was influenced by plant spatial distribution, the arrangement of plant species in the experimental arena. Increasing the number of vector host plants increased the density of aphids. Although the interaction of the plant and predator treatments affected the proportion of potato plants infected in arenas where infection occurred, and host abundance and spatial distribution impacted vector movement and viral prevalence, aphid movement did not appear to mediate the effect of plant and predator treatments on PVY prevalence. This work demonstrates that both wingless non-colonizing vector behavior and transmission are aggregated responses to multiple environmental drivers. [ABSTRACT FROM AUTHOR]

Many studies that provided evidence for a positive relationship between plant diversity and productivity have proposed that this effect may be explained by complementarity among species in resources utilization, or selection of particularly productive species in high-diversity plant communities. Recent studies have related the higher productivity in diverse plant communities to suppression of pathogenic soil biota. If soil biota plays a role in diversity-productivity relationships, the question remains about how they may influence complementarity and selection effects., Here we examine how complementarity and selection effects may depend on soil biota using a plant-soil feedback approach. We used monocultures and mixtures of early successional plant species, which are known to have mostly negative plant-soil feedback effects, and mid-successional plant species, which generally have neutral plant-soil feedback., We found that plant-soil feedback effects differed between monocultures and mixed plant communities, as well as between early and mid-successional plants. This resulted in a significant interaction effect between diversity and successional stage. In monocultures, plant-soil feedback tended to be negative for early and positive for mid-successional plant species. Interestingly, the community feedback responses of the mixed communities were opposite, being positive for early and negative for mid-successional community., Plant-soil feedback differentially affected complementarity and selection effects of early and mid-successional plant communities: it enhanced complementarity effects of early and decreased selection effects of mid-successional species., Synthesis. Soil biota that drive plant-soil feedback effects can influence the diversity-productivity relationship not only through decreased biomass production in monocultures compared to mixtures, but also through influencing complementarity and selection effects among species in mixed plant communities. Our results reveal that biodiversity-productivity relationships depend on plant-soil feedback interactions, which depend on the successional position of the plant. We propose that including successional position and trait-based analyses of plant-soil feedback in diversity-functioning studies will enhance understanding consequences of biodiversity loss for productivity and other ecosystem processes. [ABSTRACT FROM AUTHOR]

Plants have evolved different strategies to resist pathogens, but little is known about how effective, stable and costly these mechanisms are in perennial plants across multiple growing seasons., We conducted a laboratory experiment to assess resistance variation in Plantago lanceolata against the powdery mildew-causing fungus Podosphaera plantaginis and to measure possible trade-offs between the different resistance strategies. To test stability and costs of resistance, we established common garden populations of plants possessing three different resistance strategies: qualitative resistance that is the ability to block pathogen infection, quantitative resistance that is the ability to mitigate pathogen development and susceptibility. We measured their performance with and without disease for 3 years., There were no trade-offs between qualitative and quantitative resistance, and the components of quantitative resistance were positively correlated., Throughout the 3-year common garden study, pathogen loads were significantly affected by host resistance in the study populations. Qualitative resistance efficiently blocked infections but contrary to laboratory obtained results; quantitative resistance did not hinder epidemic growth., We detected costs in plant performance for qualitative and quantitative resistance compared to susceptible plants in absence of the pathogen. The costs of infection varied according to resistance strategy, pathogen load and plant age., Synthesis. In perennial plants, the costs and benefits of resistance need to be evaluated over multiple years as they may change with plant age. Our results give new insights into how polymorphism in resistance can be maintained through costs of resistance in plant performance and through shifts in resource allocation between vegetative growth and reproduction under infection. [ABSTRACT FROM AUTHOR]

The article describes an approach in predicting insect populations in agroecosystems. It explores whether nonagricultural landscapes can directly control agricultural pests and examines how multiple spatial scales of land use affect insect populations. The study suggest that farm planning and government policies for diversification of local and regional agricultural landscapes show promise for increasing biological control and directly suppressing agricultural pests.

Host-pathogen interactions may be governed by the number of pathogens coexisting within an individual host (i.e., coinfection) and among different hosts, although most sampling in natural systems focuses on the prevalence of single pathogens and/or single hosts. We measured the prevalence of four barley and cereal yellow dwarf viruses (B/CYDVs) in three grass species at 26 natural grasslands along a 2000-km latitudinal gradient in the western United States and Canada. B/CYDVs are aphid-vectored RNA viruses that cause one of the most prevalent of all plant diseases worldwide. Pathogen prevalence and coinfection were uncorrelated, suggesting that different forces likely drive them. Coinfection, the number of viruses in a single infected host (α diversity), did not differ among host, species but increased roughly twofold across our latitudinal transect. This increase in coinfection corresponded with a decline in among-host pathogen turnover (β diversity), suggesting that B/CYDVs in northern populations experience less transmission limitation than in southern populations. In contrast to pathogen diversity, pathogen prevalence was a function of host identity as well as biotic and abiotic environmental conditions. Prevalence declined with precipitation and increased with soil nitrate concentration, an important limiting nutrient for hosts and vectors of B/CYDVs. This work demonstrates the need for further studies of processes governing coinfection, and the utility of applying theory developed to explain diversity in communities of free-living organisms to pathogen systems. [ABSTRACT FROM AUTHOR]

The article presents a study on the fitness effects of virus-resistance transgenes in wild Cucurbita pepo. A solid basis for environmental risk assessments of crops genetically-engineered for virus resistance is provided in combination with documentation of the probability of crop-to-wild gene flow and surveys of virus incidence in wild populations. It states that virus-resistance transgenes and conventional crop genes can increase fecundity of wild plants under virus pressure. The role of the gene flow from transgenic, virus-resistant squash in increasing C. pepo fecundity is predicted.