Lightweight means of actuation for use in space-based robotics applications

In the field of robotics many researchers have devoted a large amount of time to pursuing means to reduce the weight of robotic systems. For space robotics, this becomes even more important due to launch cost being directly affected by weight. During review, potential progress involving weight reduction of actuators has been encountered, which it is necessary to investigate further in order to ascertain the potential advantages and disadvantages of such work. The contribution to be put forth here is a review of means by which reductions in weight can be achieved, with particular emphasis on space robotic actuation sub-systems. Ideas will be posited about the possible configurations which could be explored to reduce weight whilst attempting to maintain performance. It is expected that this contribution will provide evidence-based support for some future research directions, and will also help to stimulate discussion and further work on the subject of lightweight robotics and lightweight actuators. The next stages of this project aim to enhance some of the actuation ideas investigated so far, test these comparatively against one another, and critically review them alongside existing lightweight actuation methods. Following this, simulation of actuation concepts being applied to robotic applications will take place. This is in order to evaluate their performance in microgravity environments and to test their versatility. This process, as part of this project, will also be discussed in this pape

Club Sport Legal Liability Practices at NIRSA Institutions

Current legal practices in collegiate club sport programs were studied. A 23-item questionnaire consisting primarily of close-ended questions was mailed to 563 campus recreation directors representing all six National Intramural-Recreational Sports Association (NIRSA) regions. Data obtained showed that mean club sport budgets ranged from $51,657 in Region 4 to$135,657 in Region 6, with an overall mean of $69,138 across all regions. Signing a waiver before participating was required by 91 % of the directors. Lack of consistency in waiver language and font size was reported. Only 9% of campus recreation directors always require that an institutional employee travel with a club sport team. The most frequent modes of approved travel for club sport participants were students driving personal cars (94%), renting vans from outside vendors (95%), and the use of private transportation such as a chartered bus (70%). Paid coaches were used by 15% of the directors

Selected Risk Management Policies, Practices, and Procedures for Intramural Activities at NIRSA Institutions

A survey of all National Intramural-Recreational Sports Association (NIRSA) campus recreation directors was conducted to determine the risk management policies, practices, and procedures relating to intramural activities and recreational sports at colleges and universities throughout North America. The survey instrument, in its final form, addressed practices, policies, and procedures of campus recreation directors through 44 questions relating to the following areas: (a) documentation, (b) medical factors, (c) rules and regulations, (d) physical supervision, (e) sportsmanship rating systems, (f) restrictive policies, (g) safety devices, (h) officials-tests-qualifications, and (i) background experiences and training of the respondents. Selected data are presented in terms of (a) the size of institutions (small, medium, and large), (b) location of the institution (rural, urban, and suburban), and (c) whether public or privately supported

Factors Affecting Risk Management of Indoor Campus Recreation Facilities

Factors affecting risk management of indoor campus recreation facilities were studied. Campus recreation directors of 4-year colleges/universities in North America who held memberships in the National Intramural-Recreational Sports Association (NIRSA) responded to a paper survey consisting of 32 dichotomous yes/no and closeended multiple-choice questions. Questions addressed staff certification requirements, use of waivers, number of automatic external defibrillators (AEDs) in the facility, communication and security devices, health screening of participants, and in-person supervision of the facility. Results showed that facilities are open to participants extensively throughout the 7-day week, thus requiring directors to ensure their risk management procedures are up to date—most notably staff members’ CPR and first aid certification, as well as AED training

Utility of ambulatory electrocardiographic monitoring for predicting recurrence of sustained ventricular tachyarrhythmias in patients receiving amiodarone

The prognostic implications of changes in ventricular ectopic activity on serial 24 hour ambulatory electrocardiographic (Holter) recordings were prospectively evaluated in 107 patients with a history of sustained ventricular tachyarrhythmias treated with amiodarone for at least 30 days. Twenty-seven patients (25%) had insufficient ventricular ectopic activity < 10 ventricular premature complexes/h and no repetitive forms) on baseline Holter recordings for serial statistical analysis. In 53 (66%) of the remaining 80 patients, serial 24 hour Holter monitor recordings showed efficacy of treatment, defined as a 75% decrease in ventricular premature complexes, a 95% decrease in ventricular couplets and absence of ventricular tachycardia. During a mean followup period of 14.2 ± 9.9 months, 34 (32%) of the 107 patients had recurrence of a sustained ventricular tachyarrhythmia. Holter recording correctly predicted nine recurrences and correctly identified 37 patients who did not experience a recurrence. Holter efficacy failed to predict recurrence of a sustained ventricular tachyarrhythmia in 16 patients, and 18 patients remained free of recurrence despite failure to achieve Holter efficacy. The positive predictive value of Holter monitoring efficacy was 33% and the negative predictive value was 70%; however, these differences were not statistically significant by chi-square analysis. Similar results were obtained using Holter recordings performed relatively early in therapy (6 weeks and 4 months).Of the 27 patients without significant ventricular ectopic activity on the baseline Holter recording, 9 had an arrhythmia recurrence despite continued infrequent ventricular premature complexes and no repetitive forms on subsequent recordings. The recurrence rate in this group (33%) was similar to the overall recurrence rate.Therefore, among patients taking amiodarone for sustained ventricular tachyarrhythmias: 1) 25% will have insufficient ventricular ectopic activity on 24 hour Holter recordings for serial statistical analysis; and 2) in the remaining 75%, data obtained from serial Holter recordings are not predictive of arrhythmia recurrence

Herbaceous production lost to tree encroachment in United States rangelands

1. Rangelands of the United States provide ecosystem services that benefit society and rural economies. Native tree encroachment is often overlooked as a primary threat to rangelands due to the slow pace of tree cover expansion and the positive public perception of trees. Still, tree encroachment fragments these landscapes and reduces herbaceous production, thereby threatening habitat quality for grassland wildlife and the economic sustainability of animal agriculture. 2. Recent innovations in satellite remote sensing permit the tracking of tree encroachment and the corresponding impact on herbaceous production. We analysed tree cover change and herbaceous production across the western United States from 1990 to 2019. 3. We show that tree encroachment is widespread in US rangelands; absolute tree cover has increased by 50% (77,323 km2) over 30 years, with more than 25% (684,852 km2) of US rangeland area experiencing tree cover expansion. Since 1990, 302 ± 30 Tg of herbaceous biomass have been lost. Accounting for variability in livestock biomass utilization and forage value reveals that this lost production is valued at between $4.1–$ 5.6 billion US dollars. 4. Synthesis and applications. The magnitude of impact of tree encroachment on rangeland loss is similar to conversion to cropland, another well-known and primary mechanism of rangeland loss in the US Prioritizing conservation efforts to prevent tree encroachment can bolster ecosystem and economic sustainability, particularly among privately-owned lands threatened by land-use conversion

Dynamic Visual Acuity: a Functionally Relevant Research Tool

Coordinated movements between the eyes and head are required to maintain a stable retinal image during head and body motion. The vestibulo-ocular reflex (VOR) plays a significant role in this gaze control system that functions well for most daily activities. However, certain environmental conditions or interruptions in normal VOR function can lead to inadequate ocular compensation, resulting in oscillopsia, or blurred vision. It is therefore possible to use acuity to determine when the environmental conditions, VOR function, or the combination of the two is not conductive for maintaining clear vision. Over several years we have designed and tested several tests of dynamic visual acuity (DVA). Early tests used the difference between standing and walking acuity to assess decrements in the gaze stabilization system after spaceflight. Supporting ground-based studies measured the responses from patients with bilateral vestibular dysfunction and explored the effects of visual target viewing distance and gait cycle events on walking acuity. Results from these studies show that DVA is affected by spaceflight, is degraded in patients with vestibular dysfunction, changes with target distance, and is not consistent across the gait cycle. We have recently expanded our research to include studies in which seated subjects are translated or rotated passively. Preliminary results from this work indicate that gaze stabilization ability may differ between similar active and passive conditions, may change with age, and can be affected by the location of the visual target with respect to the axis of motion. Use of DVA as a diagnostic tool is becoming more popular but the functional nature of the acuity outcome measure also makes it ideal for identifying conditions that could lead to degraded vision. By doing so, steps can be taken to alter the problematic environments to improve the man-machine interface and optimize performance

Refining the global spatial limits of dengue virus transmission by evidence-based consensus.

BACKGROUND: Dengue is a growing problem both in its geographical spread and in its intensity, and yet current global distribution remains highly uncertain. Challenges in diagnosis and diagnostic methods as well as highly variable national health systems mean no single data source can reliably estimate the distribution of this disease. As such, there is a lack of agreement on national dengue status among international health organisations. Here we bring together all available information on dengue occurrence using a novel approach to produce an evidence consensus map of the disease range that highlights nations with an uncertain dengue status. METHODS/PRINCIPAL FINDINGS: A baseline methodology was used to assess a range of evidence for each country. In regions where dengue status was uncertain, additional evidence types were included to either clarify dengue status or confirm that it is unknown at this time. An algorithm was developed that assesses evidence quality and consistency, giving each country an evidence consensus score. Using this approach, we were able to generate a contemporary global map of national-level dengue status that assigns a relative measure of certainty and identifies gaps in the available evidence. CONCLUSION: The map produced here provides a list of 128 countries for which there is good evidence of dengue occurrence, including 36 countries that have previously been classified as dengue-free by the World Health Organization and/or the US Centers for Disease Control. It also identifies disease surveillance needs, which we list in full. The disease extents and limits determined here using evidence consensus, marks the beginning of a five-year study to advance the mapping of dengue virus transmission and disease risk. Completion of this first step has allowed us to produce a preliminary estimate of population at risk with an upper bound of 3.97 billion people. This figure will be refined in future work

Global temperature constraints on Aedes aegypti and Ae. albopictus persistence and competence for dengue virus transmission.

BACKGROUND: Dengue is a disease that has undergone significant expansion over the past hundred years. Understanding what factors limit the distribution of transmission can be used to predict current and future limits to further dengue expansion. While not the only factor, temperature plays an important role in defining these limits. Previous attempts to analyse the effect of temperature on the geographic distribution of dengue have not considered its dynamic intra-annual and diurnal change and its cumulative effects on mosquito and virus populations. METHODS: Here we expand an existing modelling framework with new temperature-based relationships to model an index proportional to the basic reproductive number of the dengue virus. This model framework is combined with high spatial and temporal resolution global temperature data to model the effects of temperature on Aedes aegypti and Ae. albopictus persistence and competence for dengue virus transmission. RESULTS: Our model predicted areas where temperature is not expected to permit transmission and/or Aedes persistence throughout the year. By reanalysing existing experimental data our analysis indicates that Ae. albopictus, often considered a minor vector of dengue, has comparable rates of virus dissemination to its primary vector, Ae. aegypti, and when the longer lifespan of Ae. albopictus is considered its competence for dengue virus transmission far exceeds that of Ae. aegypti. CONCLUSIONS: These results can be used to analyse the effects of temperature and other contributing factors on the expansion of dengue or its Aedes vectors. Our finding that Ae. albopictus has a greater capacity for dengue transmission than Ae. aegypti is contrary to current explanations for the comparative rarity of dengue transmission in established Ae. albopictus populations. This suggests that the limited capacity of Ae. albopictus to transmit DENV is more dependent on its ecology than vector competence. The recommendations, which we explicitly outlined here, point to clear targets for entomological investigation

General practitioner practice-based pharmacist input to medicines optimisation in the UK: pragmatic, multicenter, randomised, controlled trial

BACKGROUND: Changing demographics across the UK has led to general practitioners (GPs) managing increasing numbers of older patients with multi-morbidity and resultant polypharmacy. Through government led initiatives within the National Health Service, an increasing number of GP practices employ pharmacist support. The purpose of this study is to evaluate the impact of a medicines optimisation intervention, delivered by GP practice-based pharmacists, to patients at risk of medication-related problems (MRPs), on patient outcomes and healthcare costs. METHODS: A multi-centre, randomised (normal care or pharmacist supplemented care) study in four regions of the UK, involving patients (n = 356) from eight GP practices, with a 6-month follow-up period. Participants were adult patients who were at risk of MRPs. RESULTS: Median number of MRPs per intervention patient were reduced at the third assessment, i.e. 3 to 0.5 (p < 0.001) in patients who received the full intervention schedule. Medication Appropriateness Index (MAI) scores were reduced (medications more appropriate) for the intervention group, but not for control group patients (8 [4-13] to 5 [0-11] vs 8 [3-13] to 7 [3-12], respectively; p = 0.001). Using the intention-to-treat (ITT) approach, the number of telephone consultations in intervention group patients was reduced and different from the control group (1 [0-3] to 1 [0-2] vs 1 [0-2] to 1 [0-3], p = 0.020). No significant differences between groups were, however, found in unplanned hospital admissions, length of hospital stay, number of A&E attendances or outpatient visits. The mean overall healthcare cost per intervention patient fell from £1041.7 ± 1446.7 to £859.1 ± 1235.2 (p = 0.032). Cost utility analysis showed an incremental cost per patient of - £229.0 (95% CI - 594.6, 128.2) and a mean QALY gained of 0.024 (95% CI - 0.021 to 0.065), i.e. indicative of a health status gain at a reduced cost (2016/2017). CONCLUSION: The pharmacist service was effective in reducing MRPs, inappropriateness of medications and telephone consultations in general practice in a cost-effective manner. TRIAL REGISTRATION: ClinicalTrials.Gov, NCT03241498. Registered 7 August 2017-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT03241498