Odometry Correction of a Mobile Robot Using a Range-Finding Laser

Two methods for improving odometry using a pan-tilt range-finding laser is considered. The first method is a one-dimensional model that uses the laser with a sliding platform. The laser is used to determine how far the platform has moved along a rail. The second method is a two-dimensional model that mounts the laser to a mobile robot. In this model, the laser is used to improve the odometry of the robot. Our results show that the one-dimensional model proves our basic geometry is correct, while the two-dimensional model improves the odometry, but does not completely correct it

Development of theory-based health messages: three-phase programme of formative research

Online health behaviour interventions have great potential but their effectiveness may be hindered by a lack of formative and theoretical work. This paper describes the process of formative research to develop theoretically and empirically based health messages that are culturally relevant and can be used in an online intervention to promote healthy lifestyle behaviours among new university students. Drawing on the Theory of Planned Behaviour, a three-phase programme of formative research was conducted with prospective and current undergraduate students to identify (i) modal salient beliefs (the most commonly held beliefs) about fruit and vegetable intake, physical activity, binge drinking and smoking, (ii) which beliefs predicted intentions/behaviour and (iii) reasons underlying each of the beliefs that could be targeted in health messages. Phase 1, conducted with 96 pre-university college students, elicited 56 beliefs about the behaviours. Phase 2, conducted with 3026 incoming university students, identified 32 of these beliefs that predicted intentions/behaviour. Phase 3, conducted with 627 current university students, elicited 102 reasons underlying the 32 beliefs to be used to construct health messages to bolster or challenge these beliefs. The three-phase programme of formative research provides researchers with an example of how to develop health messages with a strong theoretical- and empirical base for use in health behaviour change interventions

The cost-effectiveness of an updated theory-based online health behavior intervention for new university students: U@Uni2

Background: The transition to university marks a point where young people may be open to changing health behaviours such as smoking, exercise, diet and alcohol intake. This study aimed to estimate the cost-effectiveness of an updated online health behaviour intervention for new university students in the UK – “U@Uni2”, compared with both a control (measurement only) scenario and with the original intervention (“U@Uni1”). Methods: The economic analysis, based on a randomised controlled trial, comprised a detailed costing analysis, a within-trial cost-effectiveness analysis and long-term economic modelling. Cost-effectiveness of the U@Uni2 trial was estimated using 6-month data on costs and health-related quality of life. An individual patient simulation model was adapted for long-term economic analysis of U@Uni2. Probabilistic sensitivity analysis and value of information analysis accounted for uncertainty in model inputs and identified key parameters. Results: The U@Uni2 intervention costs £45.97 per person for full implementation, £10.43 per person for roll-out in a different institution and £3.03 per person for roll-out over five years. The U@Uni2 trial was not cost-effective because marginally fewer quality-adjusted life years (QALYs) were obtained in the intervention arm than control. However, modelled over a lifetime, U@Uni2 is estimated to produce more QALYs than control but fewer than U@Uni1, primarily due to the effect of the interventions on smoking. Roll-out of U@Uni2 is highly likely to be more cost-effective than doing nothing (ICER = £536 per QALY, 86% probability cost-effective). Decision uncertainty occurs primarily around the effectiveness of the U@Uni2 intervention and is worth up to £3.24m. Conclusions: The U@Uni2 intervention is highly likely to be cost-effective to roll-out compared with doing nothing. The results suggest that preventing uptake of smoking is the key driver of QALY gain and should be the primary target of such interventions. Trial Registration: Current Controlled Trials ISRCTN6768418

2-Aminoacetophenone as a potential breath biomarker for Pseudomonas aeruginosa in the cystic fibrosis lung

<p>Abstract</p> <p>Background</p> <p><it>Pseudomonas aeruginosa </it>infections are associated with progressive life threatening decline of lung function in cystic fibrosis sufferers. Growth of <it>Ps. aeruginosa </it>releases a "grape-like" odour that has been identified as the microbial volatile organic compound 2-aminoacetophenone (2-AA).</p> <p>Methods</p> <p>We investigated 2-AA for its specificity to <it>Ps. aeruginosa </it>and its suitability as a potential breath biomarker of colonisation or infection by Solid Phase Micro Extraction and Gas Chromatography-Mass Spectrometry (GC/MS).</p> <p>Results</p> <p>Cultures of 20 clinical strains of <it>Ps. aeruginosa </it>but not other respiratory pathogens had high concentrations of 2-AA in the head space of <it>in vitro </it>cultures when analysed by GC/MS. 2-AA was stable for 6 hours in deactivated glass sampling bulbs but was not stable in Tedlar^®bags. Optimisation of GC/MS allowed detection levels of 2-AA to low pico mol/mol range in breath. The 2-AA was detected in a significantly higher proportion of subjects colonised with <it>Ps. aeruginosa </it>15/16 (93.7%) than both the healthy controls 5/17 (29%) (p < 0.0002) and CF patients not colonised with <it>Ps. aeruginosa </it>4/13(30.7%) (p < 0.001). The sensitivity and specificity of the 2-AA breath test compared to isolation of <it>Ps. aeruginosa </it>in sputum and/or BALF was 93.8% (95% CI, 67-99) and 69.2% (95% CI, 38-89) respectively. The peak integration values for 2-AA analysis in the breath samples were significantly higher in <it>Ps. aeruginosa </it>colonised subjects (median 242, range 0-1243) than the healthy controls (median 0, range 0-161; p < 0.001) and CF subjects not colonised with <it>Ps. aeruginosa </it>(median 0, range 0-287; p < 0.003)</p> <p>Conclusions</p> <p>Our results report 2-AA as a promising breath biomarker for the detection of <it>Ps. aeruginosa </it>infections in the cystic fibrosis lung.</p

A theory-based online health behaviour intervention for new university students (U@Uni): results from a randomised controlled trial

BACKGROUND Too few young people engage in behaviours that reduce the risk of morbidity and premature mortality, such as eating healthily, being physically active, drinking sensibly and not smoking. This study sought to assess the efficacy and cost-effectiveness of a theory-based online health behaviour intervention (based on self-affirmation theory, the Theory of Planned Behaviour and implementation intentions) targeting these behaviours in new university students, in comparison to a measurement-only control. METHODS Two-weeks before starting university all incoming undergraduates at the University of Sheffield were invited to take part in a study of new students' health behaviour. A randomised controlled design, with a baseline questionnaire, and two follow-ups (1 and 6 months after starting university), was used to evaluate the intervention. Primary outcomes were measures of the four health behaviours targeted by the intervention at 6-month follow-up, i.e., portions of fruit and vegetables, metabolic equivalent of tasks (physical activity), units of alcohol, and smoking status. RESULTS The study recruited 1,445 students (intervention n = 736, control n = 709, 58% female, Mean age = 18.9 years), of whom 1,107 completed at least one follow-up (23% attrition). The intervention had a statistically significant effect on one primary outcome, smoking status at 6-month follow-up, with fewer smokers in the intervention arm (8.7%) than in the control arm (13.0%; Odds ratio = 1.92, p = .010). There were no significant intervention effects on the other primary outcomes (physical activity, alcohol or fruit and vegetable consumption) at 6-month follow-up. CONCLUSIONS The results of the RCT indicate that the online health behaviour intervention reduced smoking rates, but it had little effect on fruit and vegetable intake, physical activity or alcohol consumption, during the first six months at university. However, engagement with the intervention was low. Further research is needed before strong conclusions can be made regarding the likely effectiveness of the intervention to promote health lifestyle habits in new university students. TRIAL REGISTRATION Current Controlled Trials, ISRCTN67684181

Adjunctive intravenous then oral vitamin C for moderate and severe community-acquired pneumonia in hospitalized adults: Feasibility of randomized controlled trial

Patients hospitalised with community acquired pneumonia (CAP) have low peripheral blood vitamin C concentrations and limited antioxidant capacity. The feasibility of a trial of vitamin C supplementation to improve patient outcomes was assessed. Participants with moderate and severe CAP (CURB-65 ≥ 2) on intravenous antimicrobial treatment were randomised to either intravenous vitamin C (2.5 g 8 hourly) or placebo before switching to oral intervention (1 g tds) for 7 days when they were prescribed oral antimicrobial therapy. Of 344 patients screened 75 (22%) were randomised and analysed. The median age was 76 years, and 43 (57%) were male. In each group, one serious adverse event that was potentially intervention related occurred, and one subject discontinued treatment. Vitamin C concentrations were 226 µmol/L in the vitamin C group and 19 µmol/L in the placebo group (p < 0.001) after 3 intravneous doses. There were no signficant differences between the vitamin C and placebo groups for death within 28 days (0 vs. 2; p = 0.49), median length of stay (69 vs. 121 h; p = 0.07), time to clinical stability (22 vs. 49 h; p = 0.08), or readmission within 30 days (1 vs. 4; p = 0.22). The vitamin C doses given were safe, well tolerated and saturating. A randomised controlled trial to assess the efficacy of vitamin C in patients with CAP would require 932 participants (CURB-65 ≥ 2) to observe a difference in mortality and 200 participants to observe a difference with a composite endpoint such as mortality plus discharge after 7 days in hospital. These studies are feasible in a multicentre setting

Evaluating the Viability of Successive Ring-Expansions Based on Amino Acid and Hydroxyacid Side-Chain Insertion

The outcome of ring expansion reactions based on amino/hydroxyacid side chain insertion is strongly dependent on ring size. This manuscript, which builds upon our previous work on Successive Ring Expansion (SuRE) methods, details efforts to better define the scope and limitations of these reactions on lactam and β-ketoester ring systems with respect to ring size and additional functionality. The synthetic results provide clear guidelines as to which substrate classes are more likely to be successful and are supported by computational results, using a Density Functional Theory (DFT) approach. Calculating the relative Gibbs free energies of the three isomeric species that are formed reversibly during ring expansion enables the viability of new synthetic reactions to be correctly predicted in most cases. The new synthetic and computational results are expected to support the design of new lactam- and β-ketoester-based ring expansion reactions

The cost-effectiveness of a theory-based online health behaviour intervention for new university students: an economic evaluation

Background: Too many young people engage in unhealthy behaviours such as eating unhealthily, being physically inactive, binge drinking and smoking. This study aimed to estimate the short-term and long-term cost-effectiveness of a theory-based online health behaviour intervention (“U@Uni”) in comparison with control in young people starting university. Methods: A costing analysis was conducted to estimate the full cost of U@Uni and the cost of U@Uni roll-out. The short-term cost-effectiveness of U@Uni was estimated using statistical analysis of 6-month cost and health-related quality of life data from the U@Uni randomised controlled trial. An economic modelling analysis combined evidence from the trial with published evidence of the effect of health behaviours on mortality risk and general population data on health behaviours, to estimate the lifetime cost-effectiveness of U@Uni in terms of incremental cost per QALY. Costs and effects were discounted at 1.5% per annum. A full probabilistic sensitivity analysis was conducted to account for uncertainty in model inputs and provide an estimate of the value of information for groups of important parameters. Results: To implement U@Uni for the randomised controlled trial was estimated to cost £292 per participant, whereas roll-out to another university was estimated to cost £19.71, both giving a QALY gain of 0.0128 per participant. The short-term (6-month) analysis suggested that U@Uni would not be cost-effective at a willingness-to-pay threshold of £20,000 per QALY (incremental cost per QALY gained = £243,926). When a lifetime horizon was adopted the results suggest that the full implementation of U@Uni is unlikely to be cost-effective, whereas the roll-out of U@Uni to another university is extremely likely to be cost-effective. The value of information analysis suggests that the most important drivers of decision uncertainty are uncertainties in the effect of U@Uni on health behaviours. Conclusions: The study provides the first estimate of the costs and cost-effectiveness of an online health behaviour intervention targeted at new university students. The results suggest that the roll-out, but not the full implementation, of U@Uni would be a cost-effective decision for the UK Department of Health, given a lifetime perspective and a willingness-to pay threshold of £20,000 per QALY. Trial registration: Current Controlled Trials ISRCTN67684181

A theory-based online health behavior intervention for new university students: study protocol

Background Too few young people engage in behaviors that reduce the risk of morbidity and premature mortality, such as eating healthily, being physically active, drinking sensibly and not smoking. The present research developed an online intervention to target these health behaviors during the significant life transition from school to university when health beliefs and behaviors may be more open to change. This paper describes the intervention and the proposed approach to its evaluation. Methods/design Potential participants (all undergraduates about to enter the University of Sheffield) will be emailed an online questionnaire two weeks before starting university. On completion of the questionnaire, respondents will be randomly assigned to receive either an online health behavior intervention (U@Uni) or a control condition. The intervention employs three behavior change techniques (self-affirmation, theory-based messages, and implementation intentions) to target four heath behaviors (alcohol consumption, physical activity, fruit and vegetable intake, and smoking). Subsequently, all participants will be emailed follow-up questionnaires approximately one and six months after starting university. The questionnaires will assess the four targeted behaviors and associated cognitions (e.g., intentions, self-efficacy) as well as socio-demographic variables, health status, Body Mass Index (BMI), health service use and recreational drug use. A sub-sample of participants will provide a sample of hair to assess changes in biochemical markers of health behavior. A health economic evaluation of the cost effectiveness of the intervention will also be conducted. Discussion The findings will provide evidence on the effectiveness of online interventions as well as the potential for intervening during significant life transitions, such as the move from school to university. If successful, the intervention could be employed at other universities to promote healthy behaviors among new undergraduates. Trial registration Current Controlled Trials, ISRCTN67684181