Project ASTER: True Microgravity during Free-Fall with Attitude Stabilisation

The verification of a spacecraft component’s functionality under microgravity conditions is an important topic for the low-cost development of CubeSat components. The testing and verification of new components is often carried out on technological demonstration missions. In order to reduce the budget and time required, the verification process can also be undertaken on sounding rockets. In order to achieve true microgravity conditions, the testing platform must be entirely stabilised. Most sounding rockets are spin stabilised and, therefore, a centrifugal force acting upon the components remains. This force can be eliminated by ejecting the testing platform on a fully stabilised Free Falling Unit. Available attitude control systems are targeted at orbital flights, and therefore act slowly. Such systems measure their attitude control manoeuvres in orbits rather than minutes or seconds, which is suboptimal as experiments conducted on Free Falling Units are highly constrained by flight time. Taking these requirements into account, the objective of Project ASTER is to design and test a low-cost solution, utilising reaction wheels to stabilise and orientate in a reduced gravity environment. The results of the project will be published on an open source basis to ensure its future availability to student and low budget research projects

A Comparative Analysis of the Chronic Effects of Fine Particulate Matter

The American Cancer Society study (ACS) and the Harvard Six Cities study (SCS) are the two landmark cohort studies for estimating the chronic effects of fine particulate matter PM2.5 on mortality. To date, no comparative analysis of these studies has been carried out using a different study design, study period, data, and modeling approach. In this paper, we estimate the chronic effects of PM on mortality for the period 2000-2002 by using mortality data from Medicare and \PM levels from the National Air Pollution Monitoring Network for the same counties included in the SCS and the ACS. We use a log-linear regression model which controls for individual-level risk factors (age and gender) and area-level covariates (education, income level, poverty and employment). We found that a 10 units increase in the yearly average PM2.5 is associated with 10.9% (95% CI: 9.0, 12.8) and with 20.8% (95% CI: 12.3, 30.0) increase in all-cause mortality by using Medicare data for the ACS and SCS counties. The results are similar to those reported by the original SCS and ACS indicating that fine particulate matter is still significantly associated with mortality when more recent air pollution and mortality data are used. Our findings suggest that national government based data, like the Medicare, are useful for advancing our understanding of the chronic effects of ambient air pollution on health

The protein C pathway: implications for the design of the RESPOND study

The predictive value of plasma protein C level in sepsis has been demonstrated in a number of studies in which depressed protein C levels were associated with increased likelihood of negative outcome. Data from the PROWESS (Recombinant Human Activated Protein C Worldwide Evaluation in Severe Sepsis) trial indicate that administration of drotrecogin alfa (activated; DrotAA) leads to an increase in endogenous protein C levels in severe sepsis patients. In a group as heterogeneous as sepsis patients, the currently approved dose and duration of administration (24 μg/kg per hour for 96 hours) might not be optimal in some individuals. The RESPOND (Research Evaluating Serial Protein C levels in severe sepsis patients ON Drotrecogin alfa [activated]) trial is a phase II study being conducted to explore the use of endogenous protein C level as both a biomarker and a steering parameter for administration of DrotAA. Eligible patients will receive DrotAA either at the normal, currently approved dose and duration of administration ('standard therapy') or at a higher dose with variable infusion duration or variable infusion duration only ('alternative therapy'). The duration of DrotAA infusion in the alternative therapy arm depends on the individual response in terms of sustained increase in endogenous protein C. The ultimate aims of this and potential following studies are as follows: to establish serial plasma protein C measurement as a biomarker that will aid in the identification of severe sepsis patients who are most likely to benefit from DrotAA therapy, to enable adjustment of DrotAA therapy in individual patients (specifically, the possibility to use a higher dose and to adjust the infusion duration), and to provide guidance to the clinician regarding whether the patient is responding to DrotAA

The types and effects of feedback for emergency ambulance staff: a systematic mixed studies review and meta-analysis

Background: Extensive research has been conducted into the effects of feedback interventions within many areas of healthcare, but prehospital emergency care has been relatively neglected. Exploratory work suggests that enhancing feedback and follow-up to Emergency Medical Service (EMS) staff might provide staff with closure and improve clinical performance. Our aim was to summarise the literature on the types of feedback received by EMS professionals and its effects on the quality and safety of patient care, staff well-being and professional development. Methods: A systematic review and meta-analysis, including primary research studies of any method published in peer-reviewed journals. Studies were included if they contained information on systematic feedback to emergency ambulance staff regarding their performance. Databases searched from inception were MEDLINE, EMBASE, AMED, PsycInfo, HMIC, CINAHL and Web of Science, with searches last updated on 2nd August 2022. Study quality was appraised using the Mixed Methods Appraisal Tool. Data analysis followed a convergent integrated design involving simultaneous narrative synthesis and random-effects multilevel meta-analyses. Results: The search strategy yielded 3183 articles, with 48 studies meeting inclusion criteria after title/abstract screening and full-text review. Interventions were categorised as audit and feedback (n=31), peer-to-peer feedback (n=3), post-event debriefing (n=2), incident-prompted feedback (n=1), patient outcome feedback (n=1) or a combination thereof (n=4). Feedback was found to have a moderate positive effect on quality of care and professional development with a pooled effect of d=0.50 [95% CI 0.34, 0.67]. Feedback to EMS professionals had large effects in improving documentation (d=0.73 [0.00, 1.45]) and protocol adherence (d=0.68 [0.12, 1.24], as well as small effects in enhancing cardiac arrest performance (d=0.46 [0.06, 0.86]), clinical decision-making (d=0.47 [0.23, 0.72]), ambulance times (d=0.43 [0.12, 0.74]) and survival rates (d=0.22 [0.11, 0.33]). The between-study heterogeneity variance was estimated at σ2=0.32 (95% CI 0.22, 0.50), with an I2 value of 99% (95% CI 98%, 99%), indicating substantial statistical heterogeneity. Conclusion: This review demonstrated that the evidence base currently does not support a clear single point estimate of the pooled effect of feedback to EMS staff as a single intervention type due to study heterogeneity. Further research is needed to provide guidance and frameworks supporting better design and evaluation of feedback interventions within EMS

The role of feedback and follow up in ambulance services: a qualitative interview study

Background: International studies have shown that the feedback that ambulance staff receive lacks structure, relevance, credibility and routine implementation (Cash, 2017; Morrison, 2017). Research from psychology and implementation science suggests that feedback can change professional behaviour, improve clinical outcomes and positively influence staff mental health (Ivers, 2012; Michie and Williams, 2003). The aim of this study was to explore the experience of ambulance staff regarding current feedback provision and their views on how feedback impacts on patient safety, staff wellbeing and professional development. Methods: A qualitative study conducted as part of a wider study of work-related wellbeing in ambulance staff. 25 semi-structured interviews with prehospital staff in a clinical role from a UK ambulance service sampled using theoretical sampling. Theoretically-informed thematic analysis using psychological theory linked to the self-motives framework for feedback-seeking behaviour. Results: Study participants viewed current feedback provision as inadequate and consistently expressed a desire for increased feedback. Participants raised concerns that inadequate feedback could negatively impact on patient safety by preventing learning from mistakes. Enhancing feedback provision was suggested to improve patient safety by supporting professional development and clinical decision-making, through facilitating reflection, knowledge acquisition and professional behaviour change. Similarly, participants thought that enhanced feedback could improve staff wellbeing by enabling closure and encouraging intra-professional dialogue and peer-support. The self-motives framework was useful in interpreting personal and professional motivators for feedback-seeking behaviour within the data. Conclusions: In accordance with previous research in this area, this study highlights prehospital clinicians’ strong desire for feedback. Furthermore, it suggests that enhancing prehospital feedback could improve patient safety by enriching clinical decision-making and supporting professional development, as well as promote staff wellbeing. Findings from this initial study will be used to guide a PhD programme to address this evidence gap

Drotrecogin alfa (activated) in patients with severe sepsis presenting with purpura fulminans, meningitis, or meningococcal disease: a retrospective analysis of patients enrolled in recent clinical studies

INTRODUCTION: We report data from adult and pediatric patients with severe sepsis from studies evaluating drotrecogin alfa (activated) (DrotAA) and presenting with purpura fulminans (PF), meningitis (MEN), or meningococcal disease (MD) (PF/MEN/MD). Such conditions may be associated with an increased bleeding risk but occur in a relatively small proportion of patients presenting with severe sepsis; pooling data across clinical trials provides an opportunity for improving the characterization of outcomes. METHODS: A retrospective analysis of placebo-controlled, open-label, and compassionate-use trials was conducted. Adult patients received infusions of either DrotAA or placebo. All pediatric patients (<18 years old) received DrotAA. 189 adult and 121 pediatric patients presented with PF/MEN/MD. RESULTS: Fewer adult patients with PF/MEN/MD met cardiovascular (68.3% versus 78.8%) or respiratory (57.8% versus 80.5%) organ dysfunction entry criteria than those without. DrotAA-treated adult patients with PF/MEN/MD (n = 163) had an observed 28-day mortality rate of 19.0%, a 28-day serious bleeding event (SBE) rate of 6.1%, and an intracranial hemorrhage (ICH) rate of 4.3%. Six of the seven ICHs occurred in patients with MEN (three of whom were more than 65 years old with a history of hypertension). DrotAA-treated adult patients without PF/MEN/MD (n = 3,088) had an observed 28-day mortality rate of 25.5%, a 28-day SBE rate of 5.8%, and an ICH rate of 1.0%. In contrast, a greater number of pediatric patients with PF/MEN/MD met the cardiovascular organ dysfunction entry criterion (93.5% versus 82.5%) than those without. DrotAA-treated PF/MEN/MD pediatric patients (n = 119) had a 14-day mortality rate of 10.1%, an SBE rate of 5.9%, and an ICH rate of 2.5%. DrotAA-treated pediatric patients without PF/MEN/MD (n = 142) had a 14-day mortality rate of 14.1%, an SBE rate of 9.2%, and an ICH rate of 3.5%. CONCLUSION: DrotAA-treated adult patients with severe sepsis presenting with PF/MEN/MD had a similar SBE rate, a lower observed 28-day mortality rate, and a higher observed rate of ICH than DrotAA-treated patients without PF/MEN/MD. DrotAA-treated pediatric patients with severe sepsis with PF/MEN/MD may differ from adults, because all three outcome rates (SBE, mortality, and ICH) were lower in pediatric patients with PF/MEN/MD

Combining sequence-based prediction methods and circular dichroism and infrared spectroscopic data to improve protein secondary structure determinations

<p>Abstract</p> <p>Background</p> <p>A number of sequence-based methods exist for protein secondary structure prediction. Protein secondary structures can also be determined experimentally from circular dichroism, and infrared spectroscopic data using empirical analysis methods. It has been proposed that comparable accuracy can be obtained from sequence-based predictions as from these biophysical measurements. Here we have examined the secondary structure determination accuracies of sequence prediction methods with the empirically determined values from the spectroscopic data on datasets of proteins for which both crystal structures and spectroscopic data are available.</p> <p>Results</p> <p>In this study we show that the sequence prediction methods have accuracies nearly comparable to those of spectroscopic methods. However, we also demonstrate that combining the spectroscopic and sequences techniques produces significant overall improvements in secondary structure determinations. In addition, combining the extra information content available from synchrotron radiation circular dichroism data with sequence methods also shows improvements.</p> <p>Conclusion</p> <p>Combining sequence prediction with experimentally determined spectroscopic methods for protein secondary structure content significantly enhances the accuracy of the overall results obtained.</p