Seeing the forest not just for its trees: Exotic pathogens shift forest communities above ground and below ground

Exotic pathogens fundamentally alter ecosystems when they cause large-scale tree declines, but the resulting community-level effects are not well understood. The genus Phytophthora includes many of the most damaging exotic pathogens across the globe. For example, Phytophthora cinnamomi, on the list of 100 of the world's worst invasive species, has caused massive die-off events where it has been introduced (Burgess et al., 2017). It has its greatest impacts in Mediterranean-type climates: causing oak decline in Europe (Vettraino et al., 2002) and California (Garbelotto et al., 2006) and an estimated 40% of the 5710 plant species in Western Australia are susceptible to P. cinnamomi (Shearer et al., 2007). It is clear that exotic pathogens are becoming increasingly problematic across the globe, but less clear is how forest communities will change following large- pathogens. In this issue of New Phytologist, Domínguez-Begines et al. (2020; pp. 588–600) take a community-wide approach to evaluate seedling establishment and survival in an area devastated by P. cinnamomi. This work marks a potential pivot point in the way exotic pathogens are studied, moving from pathogen–single host dynamics to a whole community approach

Is provenance or phylogeny a better predictor of growth and survival of a soil pathogen in leaf litter?

Exotic plants have the potential to increase pathogen inoculum that can affect native plants. New Zealand's iconic kauri tree (Agathis australis) is threatened by disease caused by Phytophthora agathidicida, which is most prevalent in fragmented forests that have been invaded by or are adjacent to populations of exotic species. Exotic plants have been introduced intentionally (i.e., plantations and pastures) and unintentionally along the margins of kauri forests, yet it is unclear if invasive species play a role in pathogen spread. To determine the extent to which native and exotic plant litter supports P. agathidicida inoculum, we performed a phylogenetically controlled detached leaf assay. We inoculated 60 native and 44 invasive species’ leaves with three isolates of P. agathidicida collected from two different geographical regions of New Zealand, measured disease symptoms and re-isolated the pathogen from infected leaves. Lesions grew larger and faster on exotic leaves across all three isolates tested. However, pathogen recovery was not necessarily more likely from exotic leaves. In contrast, one of the three isolates grew faster when recovered from native compared with exotic leaves. Phylogeny did not predict disease expression. This data suggests that native and exotic plant litter may be reservoirs for P. agathidicida, but reservoir potential varies among isolates. These results also support key management tools used in New Zealand aimed at reducing pathogen spread by foot traffic in fragmented kauri forests, such as hygiene stations for shoe cleaning at trailheads and boardwalks in sensitive forest areas. Further, these tools may benefit forest management worldwide, as pathogens and exotic, invasive species increase at a global scale

Cp*Fe(Me2PCH2CH2PMe2)(CHO): Hydride shuttle reactivity of a thermally stable formyl complex

[Cp*Fe(Me2PCH2CH2PMe2)(CO)]+ [BArF24]− has been synthesised and characterised using single crystal X-ray diffraction, NMR and IR spectroscopies. Reduction of the CO ligand using Na[Et3BH] produces the corresponding neutral formyl complex Cp*Fe(Me2PCH2CH2PMe2)(CHO), that is very thermally stable, and which is attributed to the electron-releasing properties of the spectator ligands. This compound is a potent hydride donor which exists in equilibrium with [Et3BH]−, Et3B, and the structural isomer (η4-C5Me5H)Cp*Fe(Me2PCH2CH2PMe2)(CO), resulting from reversible hydride migration to the Cp* ligand

Appendix_1 – Supplemental material for Altered chemical evolution in landfill leachate post implementation of biodegradable waste diversion

<p>Supplemental material, Appendix_1 for Altered chemical evolution in landfill leachate post implementation of biodegradable waste diversion by SJ Warwick, P Durany-Fernandez, DJ Sapsford, PJ Cleall and MJ Harbottle in Waste Management & Research</p

Towards a framework for understanding the context dependence of impacts of non-native tree species

1. Biological invasions are a major driver of ecosystem change but causes of variation in their environmental impacts over space and time remain poorly understood. Most approaches used to quantify the impacts of non-native species assume there are interactions among per capita (i.e. individual level) effects, species abundance and the area occupied by the species. However, studies rarely evaluate these factors and their interactions and often fail to recognize that the magnitude of impacts can be highly context dependent. Understanding what drives the context dependence of non-native species impacts can improve our understanding and predictions of ecosystem change and better inform options for mitigation. 2. Conifers, especially pines, are among the most problematic non-native plant species globally. We use Pinaceae to illustrate how context dependence in biodiversity and environmental impacts of non-native plant species can be generated by at least four processes: nonlinear density effects; intraspecific variation in functional traits; shifts in impacts over time; and persistence of impacts as biological or ecosystem legacies following non-native species removal. Using this understanding, we develop a framework to better quantify interactions of impacts along environmental gradients (e.g. soil fertility, climate, ecosystem age). 3. We demonstrate how impacts of non-native species can occur at both low and high density, and that failing to account for intraspecific variation in effect traits can lead to significant errors in the prediction of impacts. By incorporating context dependence in regard to density and functional traits, we can measure how the interaction of this context dependence will shift along environmental gradients. Moreover, disentangling the roles of species and abundance along such gradients will provide new insights into the net effects of both the native and non-native components of communities. We use a working example of our framework that incorporates all four processes to demonstrate how to measure fire risk impacts of Pinus contorta. 4. We show that ecosystem impacts of non-native tree species are not fixed but rather vary predictably along major environmental gradients. Moreover, removal of non-native species through management provides an important tool for revealing biological and ecosystem legacy effects. Although we focus here on relatively well-documented Pinaceae, the new insights into context dependence of impacts can be widely applied across species, environments and regions

Eletromiografia de superfície para avaliação dos músculos do assoalho pélvico feminino: revisão de literatura Evaluation of female pelvic floor muscles using surface electromyography: literature review

A eletromiografia de superfície tem grande importância clínica e de pesquisa para o fisioterapeuta. Apesar de captar a atividade elétrica promovida pelo recrutamento das unidades motoras, há boa correlação entre o número de unidades ativadas e a força muscular. É um dos métodos de maior especificidade na avaliação do assoalho pélvico, embora não haja consenso em relação à sua aplicação. Essa revisão de literatura foi desenvolvida com o objetivo de agrupar as informações sobre o uso da eletromiografia de superfície na avaliação do assoalho pélvico. Foram pesquisados artigos nas bases de dados Medline, PubMed, Lilacs, SciELO e Biblioteca Cochrane, e selecionados os que avaliassem o assoalho pélvico feminino por meio de eletromiografia de superfície. Apesar de sua metodologia ainda carecer de padronização, é um instrumento que deve ser considerado nas pesquisas científicas em nosso meio, pois parece apresentar boa reprodutibilidade e confiabilidade. Pacientes com disfunções do assoalho pélvico possuem alterações no tempo de ativação dos músculos do assoalho pélvico (MAP) e músculos abdominais. Quanto à gestação e puerpério, ainda faltam evidências sobre possíveis alterações da ativação elétrica dos MAP nesses períodos.<br>Surface electromyography has clinical and research importance for the physiotherapist. Although capturing electrical activity promoted by recruitment of motor units, there is a good correlation between the number of activated units and muscle strength. This is one of the methods of higher specificity in pelvic floor evaluation, although the lack of consensus regarding its application. The aim of this literature review was to cluster information regarding to the use of surface electromyography in the evaluation of pelvic floor. Papers were searched in Medline, Pubmed Lilacs, SciELO and Cochrane Library. Were selected papers which methods used surface electromyography to evaluate the pelvic floor. Although its methodology still lacks standardization, is an instrument that should be considered in scientific research in our country because it seems to have good reproducibility and reliability. Women with pelvic floor disorders have changes in the activation time of the pelvic floor muscles (PFM) and abdominal muscles. With respect to pregnancy and postpartum, there is a lack of evidence on possible changes in electrical activation of PFM in these periods