Restoration of Lake Hakanoa: Results of model simulations

This report was requested by Waikato District Council. It covers the lake water quality of, and possible restoration scenarios for, Lake Hakanoa a riverine lake situated in Huntly. The lake is used as a recreational resource by the community. In the past it has been reported to have had very poor water quality and is known to be eutrophic. It is currently in an algal-dominated, devegetated state and has low water clarity. The shallowness of this lake makes it potentially susceptible to resuspension of sediments through wind action. A community group, Friends of Hakanoa, has been responsible for the formation of a path around the perimeter of the lake, retiring about 3.6% of the catchment from pastoral farming and creating a riparian margin. Results from more recent reports and this report indicate a trend of improving water quality which may be related to recent restoration actions such as re-establishment of a riparian margin

Modelling the flexoelectric effect in solids: a micromorphic approach

Flexoelectricity is characterised by the coupling of the gradient of the deformation and the electrical polarization in a dielectric material. A novel micromorphic approach is presented to accommodate the resulting higher-order gradient contributions arising in this highly-nonlinear and coupled problem within a classical finite element setting. The formulation accounts for all material and geometric nonlinearities, as well as the coupling between the mechanical, electrical and micromorphic fields. The highly-nonlinear system of governing equations are derived using the Dirichlet principle and solved using the finite element method. A series of numerical examples serve to elucidate the theory and to provide insight into this fascinating effect

Presence of a pre-hospital enhanced care team reduces on scene time and improves triage compliance for stab trauma

© The Author(s). 2019 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background: A reduction in pre-hospital scene time for patients with penetrating trauma is associated with reduced mortality, when combined with appropriate hospital triage. This study investigated the relationship between presence of pre-hospital enhanced care teams (ECT) (Critical Care Paramedics (CCPS) or Helicopter Emergency Medical Service (HEMS)), on the scene time and triage compliance, of penetrating trauma patients in a UK ambulance service. The primary outcome was whether scene time reduces when an ECT is present. A secondary outcome was whether the presence of an ECT improved compliance with the trust's Major Trauma Decision Tree (MTDT). Methods: All suspected penetrating trauma incidents involving a patient's torso were identified from the Trust's computer-aided dispatch (CAD) system between 31st March 2017 and 1st April 2018. Only patients who sustained central penetrating trauma were included. Any incidents involving firearms were excluded due to the prolonged times that can be involved when waiting for specialist police units. Data relevant to scene time for each eligible incident were retrieved, along with the presence or absence of an ECT. The results were analysed to identify trends in the scene times and compliance with the MTDT. Results: One hundred seventy-one patients met the inclusion criteria, with 165 having complete data. The presence of an ECT improved the median on-scene time in central stabbing by 38% (29m50s vs. 19m0s, p = 0.03). The compliance with the trust's MTDT increased dramatically when an ECT is present (81% vs. 37%, odds ratio 7.59, 95% CI, 3.70-15.37, p < 0.0001). Conclusions: The presence of an ECT at a central stabbing incident significantly improved the scene time and triage compliance with a MTDT. Ambulance services should consider routine activation of ECTs to such incidents, with subsequent service evaluation to monitor patient outcomes. Ambulance services should continue to strive to reduce scene times in the context of central penetrating trauma.Peer reviewe

The population impact of common mental disorders and long-term physical conditions on disability and hospital admission

Background: Long-term physical conditions (LTCs) consume the largest share of healthcare budgets. Although common mental disorders (CMDs) and LTCs often co-occur, the potential impact of improved mental health treatment on severe disability and hospital admissions for physical health problems remains unknown. Method: A cross-sectional study of 7403 adults aged 16–95 years living in private households in England was performed. LTCs were ascertained by prompted self-report. CMDs were ascertained by structured clinical interview. Disability was assessed using questions about problems with activities of daily living. Population impact and potential preventive gain were estimated using population-attributable fraction (PAF), and conservative estimates were obtained using ‘treated non-cases’ as the reference group. Results: Of the respondents, 20.7% reported at least one LTC. The prevalence of CMDs increased with the number of LTCs, but over two-thirds (71.2%) of CMD cases in people with LTCs were untreated. Statistically significant PAFs were found for CMDs and recent hospital admission [13.5%, 95% confidence intervals (CI) 6.6–20.0] and severe disability (31.3%, 95% CI 27.1–35.2) after adjusting for LTCs and other confounders. Only the latter remained significant when using the most conservative estimate of PAF (21.8%, 95% CI 14.0–28.9), and this was reduced only slightly when considering only participants with LTCs (18.5%, 95% CI 7.9–27.9). Conclusions: Better treatments for CMDs in people with LTCs could achieve almost the same population health gain in terms of reducing severe disability as those targeted at the entire population. Interventions to reduce the prevalence of CMDs among people with LTCs should be part of routine medical care

Robustness promotes evolvability of thermotolerance in an RNA virus

<p>Abstract</p> <p>Background</p> <p>The ability for an evolving population to adapt to a novel environment is achieved through a balance of robustness and evolvability. Robustness is the invariance of phenotype in the face of perturbation and evolvability is the capacity to adapt in response to selection. Genetic robustness has been posited, depending on the underlying mechanism, to either decrease the efficacy of selection, or increase the possibility of future adaptation. However, the true effect of genetic robustness on evolvability in biological systems remains uncertain.</p> <p>Results</p> <p>Here we demonstrate that genetic robustness increases evolvability of thermotolerance in laboratory populations of the RNA virus φ6. We observed that populations founded by robust clones evolved greater resistance to heat shock, relative to populations founded by brittle (less-robust) clones. Thus, we provide empirical evidence for the idea that robustness can promote evolvability in this environment, and further suggest that evolvability can arise indirectly via selection for robustness, rather than through direct selective action.</p> <p>Conclusion</p> <p>Our data imply that greater tolerance of mutational change is associated with virus adaptability in a new niche, a finding generally relevant to evolutionary biology, and informative for elucidating how viruses might evolve to emerge in new habitats and/or overcome novel therapies.</p

Iron bioavailability from commercially available iron supplements

Purpose: Iron deficiency anaemia (IDA) is a global public health problem. Treatment with the standard of care ferrous iron salts may be poorly tolerated, leading to non-compliance and ineffective correction of IDA. Employing supplements with higher bioavailability might permit lower doses of iron to be used with fewer side effects, thus improving treatment efficacy. Here, we compared the iron bioavailability of ferrous sulphate tablets with alternative commercial iron products, including three liquid-based supplements. Methods: Iron bioavailability was measured using Caco-2 cells with ferritin formation as a surrogate marker for iron uptake. Statistical analysis was performed using one-way ANOVA followed by either Dunnett’s or Tukey’s multiple comparisons tests. Results: Spatone Apple® (a naturally iron-rich mineral water with added ascorbate) and Iron Vital F® (a synthetic liquid iron supplement) had the highest iron bioavailability. There was no statistical difference between iron uptake from ferrous sulphate tablets, Spatone® (naturally iron-rich mineral water alone) and Pregnacare Original® (a multimineral/multivitamin tablet). Conclusion: In our in vitro model, naturally iron-rich mineral waters and synthetic liquid iron formulations have equivalent or better bioavailability compared with ferrous iron sulphate tablets. If these results are confirmed in vivo, this would mean that at-risk groups of IDA could be offered a greater choice of more bioavailable and potentially better tolerated iron preparations