A unique formulation of elastic airplane longitudinal equations of motion

Control-configured vehicle technology has increased the demand for detailed analysis of dynamic stability and control, handling and ride qualities, and control system dynamics at early stages of preliminary design. An approximate, but reasonably accurate, set of equations of motion are needed for these early analyses. Such a formulation is developed for the longitudinal dynamics of elastic airplanes. It makes use of only rigid-body aerodynamic stability derivatives in formulating the forces and moments due to elastic motion. Verification of accuracy using data for the B-1 airplane shows very good agreement. Frequencies and damping ratios of the coupled modes corresponding to complex roots of the characteristic equations agree closely with four symmetric elastic modes included

Spatial dynamics of elephant impacts on trees in Chobe national park, Botswana

The African elephant (Loxodonta africana) regulates shifts between different savanna states, primarily through herbivory of woody vegetation. As a water-dependent herbivore, these impacts on trees are constrained by water availability, potentially leading to a gradient of degradation known as the piosphere effect. Transects evaluating vegetation status with increasing distance from the Chobe River were conducted in Chobe National Park, Botswana, to test whether predictions of the piosphere effect can be applied at multiple scales. Trends varied depending on the type of utilization, with debarking by elephants decreasing with distance from the Chobe River and branch herbivory showing a bimodal distribution. Results suggest that piosphere predictions may be applicable over greater distances, with important implications for monitoring species changes far from water points. Managers should consider this as they evaluate landscape stability and discuss provisioning of waterpoints in semi-arid habitats

Emergencies, Emergences, Engagement: Cultural Relations and Climate Action

Carla Figueira and Aimee Fullman argue for the need to avoid distant, apocalyptic visions of climate change. Instead, they suggest telling ‘better stories’ about where we want to go and the sort of world we want to live in. They argue that cultural relations, and cultural relations organisations, can play a key role in shaping this new framing of climate change. Cultural relations is an underutilised resource in addressing the climate emergency, and cultural relations organisations have an important part to play. This essay is part of the British Council’s Climate Connection

Measuring performance on the Healthcare Access and Quality Index for 195 countries and territories and selected subnational locations: A systematic analysis from the Global Burden of Disease Study 2016

Background A key component of achieving universal health coverage is ensuring that all populations have access to quality health care. Examining where gains have occurred or progress has faltered across and within countries is crucial to guiding decisions and strategies for future improvement. We used the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016) to assess personal health-care access and quality with the Healthcare Access and Quality (HAQ) Index for 195 countries and territories, as well as subnational locations in seven countries, from 1990 to 2016. Methods Drawing from established methods and updated estimates from GBD 2016, we used 32 causes from which death should not occur in the presence of effective care to approximate personal health-care access and quality by location and over time. To better isolate potential effects of personal health-care access and quality from underlying risk factor patterns, we risk-standardised cause-specific deaths due to non-cancers by location-year, replacing the local joint exposure of environmental and behavioural risks with the global level of exposure. Supported by the expansion of cancer registry data in GBD 2016, we used mortality-to-incidence ratios for cancers instead of risk-standardised death rates to provide a stronger signal of the effects of personal health care and access on cancer survival. We transformed each cause to a scale of 0-100, with 0 as the first percentile (worst) observed between 1990 and 2016, and 100 as the 99th percentile (best); we set these thresholds at the country level, and then applied them to subnational locations. We applied a principal components analysis to construct the HAQ Index using all scaled cause values, providing an overall score of 0-100 of personal health-care access and quality by location over time. We then compared HAQ Index levels and trends by quintiles on the Socio-demographic Index (SDI), a summary measure of overall development. As derived from the broader GBD study and other data sources, we examined relationships between national HAQ Index scores and potential correlates of performance, such as total health spending per capita.Bill & Melinda Gates Foundatio