The Leeds Advanced Driving Simulator: Three Years In Operation

The Leeds Advanced Driving Simulator (LADS) at the University of Leeds is a medium cost fixed-base simulator and its development has been funded by the Science and Engineering Research Council (now EPSRC). It has been fully operational since mid-1993 for rural-road scenes (Carsten and Gallimore, 1993) but currently simulation of urban environments and vehicle interactions are possible too. This paper focuses on the recent development of LADS. Also detailed other recent research projects carried out in the simulator to date

The Leeds Advanced Driving Simulator: Three Years In Operation

The Leeds Advanced Driving Simulator (LADS) at the University of Leeds is a medium cost fixed-base simulator and its development has been funded by the Science and Engineering Research Council (now EPSRC). It has been fully operational since mid-1993 for rural-road scenes (Carsten and Gallimore, 1993) but currently simulation of urban environments and vehicle interactions are possible too. This paper focuses on the recent development of LADS. Also detailed other recent research projects carried out in the simulator to date

A Survey of Driving Research Simulators Around the World.

The literature review is part of the EPSRC funded project "Driver performance in the EPSRC driving simulator: a validation study". The aim of the project is to validate this simulator, located at the Department of Psychology, University of Leeds, and thereby to indicate the strengths and weaknesses of the existing configuration. It will provide guidance on how the simulator can be modified and overcome any deficiencies that are detected and also provide "benchmarks" against which other simulators can be compared. The literature review will describe the technical characteristics of the most well-known driving simulators around the world, their special features and their application areas until today. The simulators will be described and compared according to their cost (low, medium and high) and also contact addresses and photographs of the simulators will be provided by the end of the paper. In the process of gathering this information, it became apparent that there are mainly two types of papers published - either in journals or in proceedings from conferences: those describing only the technical characteristics of a specific simulator and those referring only to the applications of a specific simulator. For the first type of papers, the level of detail, format and content varies significantly where for the second one it has been proven extremely difficult to find any information about the technical characteristics of the simulator where the study had been carried out. A number of details provided in this paper are part of personal communication, or personal visits to those particular driving simulator centres or from the World Wide Web. It should also be noted here that most of the researchers contacted here offered very detail technical characteristics and application areas of their driving simulators and the author is grateful to them

Driving Simulator Validation Studies: A Literature Review.

This literature review is part of the "Driver performance in the EPSRC driving simulator: a validation study" project funded by EPSRC. It focuses mainly on driving simulator validation studies with regard to driver behaviour. Various approaches, methodologies and criteria have been proposed until today regarding the behavioral and physical validation of a driving simulator. At the same time, a number of behavioural validation studies have been conducted, with or without taking into account the proposed validation approaches. The author considered necessary this literature review because according to her knowledge there was no other published review which examined thoroughly the link between theory (proposed validation approaches and methodologies) and practice (validation studies cc driving simulators). Most of the recent behaviour validation studies have been focused on the absolute and relative validity of the simulator without taking into consideration the issue of the face validity. The format of this paper will be as follows. A small introduction to driving simulators and their usefulness will be presented first followed by the necessity of validating them. The existing validation approaches, methodologies and criteria will be analysed and earlier and recent behaviour validation studies will be reviewed and compared in detail. These studies will be classified according to the driver behaviour levels and driving performance (as they will be defined) and then will be assessed according to the validation criteria. Emphasis will be given to the interpretation of the findings from these comparisons, and in particular to their applicability in real road traffic situations

Single-cell growth kinetic behavior of pathogenic bacteria in the presence of microbial supernatants containing autoinducer-2 signal compounds

The findings of this study constitute preliminary data on the role of QS compounds on the single-cell growth behavior of important pathogens, knowledge that maybe useful in understanding the mechanisms underlying their behavior as well as in developing strategies for their control in situ

Assessment of the effect of a Salmonella enterica ser. Typhimurium culture supernatant on the single-cell lag time of foodborne pathogens

The objective of this study was the in vitro evaluation of the effect of a cell-free microbial supernatant, produced by a luxS-positive Salmonella enterica ser. Typhimurium strain, on the single-cell growth kinetic behavior of two strains of S. enterica (serotypes Enteritidis and Typhimurium) and a methicillin-resistant Staphylococcus aureus strain. The single-cell lag time (λ) of the pathogens was estimated in the absence and presence (20% v/v) of microbial supernatant based on optical density measurements. As demonstrated by the obtained results, the tested microbial supernatant had a strain-specific effect on the single-cell λ and its variability. Although the mean λ values were similar in the absence and presence of microbial supernatant in the case of Salmonella Enteritidis, a significant (P ≤ 0.05) reduction and increase in the mean value of this parameter in the presence of microbial supernatant were observed for Salmonella Typhimurium and St. aureus, respectively. With regard to the effect of the tested microbial supernatant on the single-cell variability of λ, similar λ distributions were obtained in its absence and presence for S. Enteritidis, while considerable differences were noted for the other two tested organisms; the coefficient of variation of λ in the absence and presence of microbial supernatant was 41.6 and 69.8% for S. Typhimurium, respectively, with the corresponding values for St. aureus being 74.0 and 56.9%. As demonstrated by the results of bioassays, the tested microbial supernatant exhibited autoinducer-2 activity, indicating a potential association of such quorum sensing compounds with the observed effects. Although preliminary in nature, the collected data provide a good basis for future research on the role of quorum sensing in the single-cell growth behavior of foodborne pathogens

Quorum sensing : understanding the role of bacteria in meat spoilage

Quorum sensing is a fundamental process to all of microbiology since it is ubiquitous in the bacterial world, where bacterial cells communicate with each other using low molecular weight signal molecules called autoinducers. Despite the fact that quorum sensing regulates numerous bacterial behaviours, very few studies have addressed the role of this phenomenon in foods. The microbial association of beef consists mainly of pseudomonads, Enterobacteriaceae, Brochothrix thermosphacta and lactic acid bacteria as revealed by minced beef samples purchased from retail shops, which fluctuates according to the storage conditions. Certain members of the microbial association, which are considered to produce signal molecules, have been found to be major contributors to meat spoilage. Pseudomonas fragi and Enterobacteriaceae strains, i.e., Hafnia alvei and Serratia liquefaciens are among the most common quorum sensing signal producers recovered from various food environments. Cont/d.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

The clinically extremely vulnerable to COVID: identification and changes in healthcare while self-isolating (shielding) during the coronavirus pandemic.

In March 2020, the government of Scotland identified people deemed clinically extremely vulnerable to COVID due to their pre-existing health conditions. These people were advised to strictly self-isolate (shield) at the start of the pandemic, except for necessary healthcare. We examined who was identified as clinically extremely vulnerable, how their healthcare changed during isolation, and whether this process exacerbated healthcare inequalities. We linked those on the shielding register in NHS Grampian, a health authority in Scotland, to healthcare records from 2015-2020. We described the source of identification, demographics, and clinical history of the cohort. We measured changes in out-patient, in-patient, and emergency healthcare during isolation in the shielding population and compared to the general non-shielding population. The register included 16,092 people (3% of the population), clinically vulnerable primarily due to a respiratory disease, immunosuppression, or cancer. Among them, 42% were not identified by national healthcare record screening but added ad hoc, with these additions including more children and fewer economically-deprived. During isolation, all forms of healthcare use decreased (25%-46%), with larger decreases in scheduled care than in emergency care. However, people shielding had better maintained scheduled care compared to the non-shielding general population: out-patient visits decreased 35% vs 49%; in-patient visits decreased 46% vs 81%. Notably, there was substantial variation in whose scheduled care was maintained during isolation: younger people and those with cancer had significantly higher visit rates, but there was no difference between sexes or socioeconomic levels. Healthcare changed dramatically for the clinically extremely vulnerable population during the pandemic. The increased reliance on emergency care while isolating indicates that continuity of care for existing conditions was not optimal. However, compared to the general population, there was success in maintaining scheduled care, particularly in young people and those with cancer. We suggest that integrating demographic and primary care data would improve identification of the clinically vulnerable and could aid prioritising their care

Study of the measurement and predictive validity of the Functional Movement Screen.

Objective: The aim of the study was to evaluate the reported measurement capabilities and predictive validity of the Functional Movement Screen (FMS) for injury. Methods: This was a prospective observational longitudinal study of 24 male footballers from a single team in England, alongside analysis of an existing database over one season (September 2015-May 2016). A preseason FMS was carried out with scores recorded by an experienced assessor and derived, retrospectively, from the three-dimensional movement data that were simultaneously captured. The assessor scores were compared with the photogrammetric system to determine measurement validity, and predictive validity was quantified by assessing sensitivity and specificity (cut-off score of 14). Results: The real-time assessor score matched the photogrammetric score awarded for one of the participants, was higher than the photogrammetric system for 22 participants and was lower than the photogrammetric system in 1 participant. There was no discernible relationship between FMS scores and the competencies required to be met as per the rules articulated for the allocation of a score. A higher number of total injuries were associated with higher FMS scores, whether determined through real-time assessment or codification of kinematic variables. Additionally, neither method of score determination was able to prospectively identify players at risk of serious injury. Conclusion: The FMS does not demonstrate the properties essential to be considered as a measurement scale and has neither measurement nor predictive validity. A possible reason for these observations could be the complexity in the instructions associated with the scale. Further work on eliminating redundancies and improving the measurement properties is recommended