Multimodal correlative imaging and modelling of phosphorus uptake from soil by hyphae of mycorrhizal fungi.

Phosphorus (P) is essential for plant growth. Arbuscular mycorrhizal fungi (AMF) aid its uptake by acquiring P from sources distant from roots in return for carbon. Little is known about how AMF colonise soil pore-space, and models of AMF-enhanced P-uptake are poorly validated. We used synchrotron X-ray computed tomography to visualize mycorrhizas in soil and synchrotron X-ray fluorescence/X-ray absorption near edge structure (XRF/XANES) elemental mapping for P, sulphur (S) and aluminium (Al) in combination with modelling. We found that AMF inoculation had a suppressive effect on colonisation by other soil fungi and identified differences in structure and growth rate between hyphae of AMF and nonmycorrhizal fungi. Our results showed that AMF co-locate with areas of high P and low Al, and preferentially associate with organic-type P species over Al-rich inorganic P. We discovered that AMF avoid Al-rich areas as a source of P. Sulphur-rich regions were found to be correlated with higher hyphal density and an increased organic-associated P-pool, whilst oxidized S-species were found close to AMF hyphae. Increased S oxidation close to AMF suggested the observed changes were microbiome-related. Our experimentally-validated model led to an estimate of P-uptake by AMF hyphae that is an order of magnitude lower than rates previously estimated - a result with significant implications for the modelling of plant-soil-AMF interactions.

Evaluating an inpatient deprescribing initiative at a rural community hospital in Ontario.

BACKGROUND: Deprescribing is an effective means to reduce polypharmacy in elderly patients. However, geriatric day care deprescribing services are challenging to implement in rural regions. In this study, we examined whether a subacute care unit of a rural hospital could deliver a comprehensive and multidisciplinary intervention to promote deprescribing in patients and whether this intervention would succeed in achieving significant and lasting deprescribing results. METHODS: We conducted a cross-sectional analysis of a deprescribing program at a rural hospital in Eastern Ontario, Canada. Participants were 11 patients, aged 65 or older, who were admitted to the hospital's medical/surgical unit or who presented to the emergency department. Clinicians followed a structured, comprehensive and multidisciplinary approach designed to facilitate deprescribing, which concluded with an outcome evaluation at discharge and follow-up phone calls. Outcomes included the frequency and total number of medications successfully removed, reduced, substituted and restarted after discharge and emergency department visits and hospitalizations 6 months before and after the intervention. RESULTS: Of a total 57 deprescribed medications, 38 were eliminated, 8 were switched to a safer alternative, and 11 were dose reduced. Postdischarge deprescribing reversal occurred in only 5 of 57 deprescribed medications. Among the study population, a 59.2% reduction was observed in the combined number of emergency department visits and hospitalizations 6 months after deprescribing. CONCLUSIONS: This feasibility study was successful in showing the potential added value for offering a rehabilitative, subacute care, inpatient, comprehensive and multidisciplinary approach toward patients with complex deprescribing needs. It also showed proof of concept in reducing polypharmacy-induced adverse health outcomes. Can Pharm J (Ott) 2020:153:xx-xx.

Multiple Scale Homogenisation of Nutrient Movement and Crop Growth in Partially Saturated Soil.

In this paper, we use multiple scale homogenisation to derive a set of averaged macroscale equations that describe the movement of nutrients in partially saturated soil that contains growing potato tubers. The soil is modelled as a poroelastic material, which is deformed by the growth of the tubers, where the growth of each tuber is dependent on the uptake of nutrients via a sink term within the soil representing root nutrient uptake. Special attention is paid to the reduction in void space, resulting change in local water content and the impact on nutrient diffusion within the soil as the tubers increase in size. To validate the multiple scale homogenisation procedure, we compare the system of homogenised equations to the original set of equations and find that the solutions between the two models differ by [Formula: see text]. However, we find that the computation time between the two sets of equations differs by several orders of magnitude. This is due to the combined effects of the complex three-dimensional geometry and the implementation of a moving boundary condition to capture tuber growth.

Constructions, reconstructions and deconstructions of 'family' amongst people who live apart together (LATs).

This article explores how people who live apart from their partners in Britain describe and understand 'family'. It investigates whether, and how far, non-cohabiting partners, friends, 'blood' and legal ties are seen as 'family', and how practices of care and support, and feelings of closeness are related to these constructions. It suggests that people in LAT relationships creatively draw and re-draw the boundaries of family belonging in ways that involve emotionally subjective understandings of family life, and that also refer to normative constructions of what 'family' ought to be, as well as to practical recognitions of lived family 'realities'. This often involves handling uncertainties about what constitutes 'family'.

Stabilizing gold nanoparticles for use in X-ray computed tomography imaging of soil systems.

This investigation establishes a system of gold nanoparticles that show good colloidal stability as an X-ray computed tomography (XCT) contrast agent under soil conditions. Gold nanoparticles offer numerous beneficial traits for experiments in biology including: comparatively minimal phytotoxicity, X-ray attenuation of the material and the capacity for functionalization. However, soil salinity, acidity and surface charges can induce aggregation and destabilize gold nanoparticles, hence in biomedical applications polymer coatings are commonly applied to gold nanoparticles to enhance stability in the in vivo environment. Here we first demonstrate non-coated nanoparticles aggregate in soil-water solutions. We then show coating with a polyethylene glycol (PEG) layer prevents this aggregation. To demonstrate this, PEG-coated nanoparticles were drawn through flow columns containing soil and were shown to be stable; this is in contrast with control experiments using silica and alumina-packed columns. We further determined that a suspension of coated gold nanoparticles which fully saturated soil maintained stability over at least 5 days. Finally, we used time resolved XCT imaging and image based models to approximate nanoparticle diffusion as similar to that of other typical plant nutrients diffusing in water. Together, these results establish the PEGylated gold nanoparticles as potential contrast agents for XCT imaging in soil.

Retrospective review of donor site complications after harvest of cancellous bone from the anteriomedial tibia.

Donor site morbidity is important in deciding the site for harvest of cancellous bone for alveolar bone grafts. Many studies have supported the view that tibia is safe with few complications in the short term. We know of no studies on the long-term complications to the donor site after tibial bone grafting in children with alveolar clefts. The casenotes of 40 children who had had tibial bone grafts for alveolar clefts were studied retrospectively, and parents or patients were contacted by telephone and a standardised questionnaire was used to assess any long term complications at the donor site. We found none. We found no evidence of long-term complications at the donor site in children who had had proximal tibial bone grafting for secondary repair of alveolar clefts. We conclude that the proximal tibia is a safe site from which to obtain cancellous bone graft for alveolar clefts in children. This study is preliminary, and highlights the need for a randomised trial.