Driver sleepiness self-regulation : physiological and subjective evidence

Introduction: Sleepiness contributes to a substantial proportion of fatal and severe road crashes. Efforts to reduce the incidence of sleep-related crashes have largely focussed on driver education to promote self-regulation of driving behaviour. However, effective self-regulation requires accurate self-perception of sleepiness. The aim of this study was to assess capacity to accurately identify sleepiness, and self-regulate driving cessation, during a validated driving simulator task. Methods: Participants comprised 26 young adult drivers (20-28 years) who had open licenses. No other exclusion criteria where used. Participants were partially sleep deprived (05:00 wake up) and completed a laboratory-based hazard perception driving simulation, counterbalanced to either at mid-morning or mid-afternoon. Established physiological measures (i.e., EEG, EOG) and subjective measures (Karolinska Sleepiness Scale), previously found sensitive to changes in sleepiness levels, were utilised. Participants were instructed to ‘drive’ on the simulator until they believed that sleepiness had impaired their ability to drive safely. They were then offered a nap opportunity. Results: The mean duration of the drive before cessation was 36.1 minutes (±17.7 minutes). Subjective sleepiness increased significantly from the beginning (KSS=6.6±0.7) to the end (KSS=8.2±0.5) of the driving period. No significant differences were found for EEG spectral power measures of sleepiness (i.e., theta or alpha spectral power) from the start of the driving task to the point of cessation of driving. During the nap opportunity, 88% of the participants (23/26) were able to reach sleep onset with an average latency of 9.9 minutes (±7.5 minutes). The average nap duration was 15.1 minutes (±8.1 minutes). Sleep architecture during the nap was predominately comprised of Stages I and II (combined 92%). Discussion: Participants reported high levels of sleepiness during daytime driving after very moderate sleep restriction. They were able to report increasing sleepiness during the test period despite no observed change in standard physiological indices of sleepiness. This increased subjective sleepiness had behavioural validity as the participants had high ‘napability’ at the point of driving cessation, with most achieving some degree of subsequent sleep. This study suggests that the nature of a safety instruction (i.e. how to view sleepiness) can be a determinant of driver behaviour.

A framework for cost-aware process management : generation of accurate and timely management accounting cost reports

Organisations are constantly seeking efficiency improvements for their business processes in terms of time and cost. Management accounting enables reporting of detailed cost of operations for decision making purpose, although significant effort is required to gather accurate operational data. Business process management is concerned with systematically documenting, managing, automating, and optimising processes. Process mining gives valuable insight into processes through analysis of events recorded by an IT system in the form of an event log with the focus on efficient utilisation of time and resources, although its primary focus is not on cost implications. In this paper, we propose a framework to support management accounting decisions on cost control by automatically incorporating cost data with historical data from event logs for monitoring, predicting and reporting process-related costs. We also illustrate how accurate, relevant and timely management accounting style cost reports can be produced on demand by extending open-source process mining framework ProM.

The effect of a high fat meal on postprandial arterial stiffness in men with obesity and type 2 diabetes

Context: Postprandial dysmetabolism is emerging as an important cardiovascular risk factor. Augmentation index (AIx) is a measure of systemic arterial stiffness and independently predicts cardiovascular outcome. Objective: The objective of this study was to assess the effect of a standardized high-fat meal on metabolic parameters and AIx in 1) lean, 2) obese nondiabetic, and 3) subjects with type 2 diabetes mellitus (T2DM). Design and Setting: Male subjects (lean, n = 8; obese, n = 10; and T2DM, n = 10) were studied for 6 h after a high-fat meal and water control. Glucose, insulin, triglycerides, and AIx (radial applanation tonometry) were measured serially to determine the incremental area under the curve (iAUC). Results: AIx decreased in all three groups after a high-fat meal. A greater overall postprandial reduction in AIx was seen in lean and T2DM compared with obese subjects (iAUC, 2251 +/- 1204, 2764 +/- 1102, and 1187 +/- 429% . min, respectively; P < 0.05). The time to return to baseline AIx was significantly delayed in subjects with T2DM (297 +/- 68 min) compared with lean subjects (161 +/- 88 min; P < 0.05). There was a significant correlation between iAUC AIx and iAUC triglycerides (r = 0.50; P < 0.05). Conclusions: Obesity is associated with an attenuated overall postprandial decrease in AIx. Subjects with T2DM have a preserved, but significantly prolonged, reduction in AIx after a high-fat meal. The correlation between AIx and triglycerides suggests that postprandial dysmetabolism may impact on vascular dynamics. The markedly different response observed in the obese subjects compared with those with T2DM was unexpected and warrants additional evaluation.

The use of computerised simulators for training of transthoracic and transoesophageal echocardiography. The future of echocardiographic training?

Echocardiography is the commonest form of non-invasive cardiac imaging and is fundamental to patient management. However, due to its methodology, it is also operator dependent. There are well defined pathways in training and ongoing accreditation to achieve and maintain competency. To satisfy these requirements, significant time has to be dedicated to scanning patients, often in the time pressured clinical environment. Alternative, computer based training methods are being considered to augment echocardiographic training. Numerous advances in technology have resulted in the development of interactive programmes and simulators to teach trainees the skills to perform particular procedures, including transthoracic and transoesophageal echocardiography. 82 sonographers and TOE proceduralists utilised an echocardiographic simulator and assessed its utility using defined criteria. 40 trainee sonographers assessed the simulator and were taught how to obtain an apical 2 chamber (A2C) view and image the superior vena cava (SVC). 100% and 88% found the simulator useful in obtaining the SVC or A2C view respectively. All users found it easy to use and the majority found it helped with image acquisition and interpretation. 42 attendees of a TOE training day utilising the simulator assessed the simulator with 100% finding it easy to use, as well as the augmented reality graphics benefiting image acquisition. 90% felt that it was realistic. This study revealed that both trainee sonographers and TOE proceduralists found the simulation process was realistic, helped in image acquisition and improved assessment of spatial relationships. Echocardiographic simulators may play an important role in the future training of echocardiographic skills.

Visual motion perception predicts driving hazard perception ability

PURPOSE: To examine the basis of previous findings of an association between indices of driving safety and visual motion sensitivity and to examine whether this association could be explained by low-level changes in visual function. METHODS: 36 visually normal participants (aged 19 – 80 years), completed a battery of standard vision tests including visual acuity, contrast sensitivity and automated visual fields. and two tests of motion perception including sensitivity for movement of a drifting Gabor stimulus, and sensitivity for displacement in a random-dot kinematogram (Dmin). Participants also completed a hazard perception test (HPT) which measured participants’ response times to hazards embedded in video recordings of real world driving which has been shown to be linked to crash risk. RESULTS: Dmin for the random-dot stimulus ranged from -0.88 to -0.12 log minutes of arc, and the minimum drift rate for the Gabor stimulus ranged from 0.01 to 0.35 cycles per second. Both measures of motion sensitivity significantly predicted response times on the HPT. In addition, while the relationship involving the HPT and motion sensitivity for the random-dot kinematogram was partially explained by the other visual function measures, the relationship with sensitivity for detection of the drifting Gabor stimulus remained significant even after controlling for these variables. CONCLUSION: These findings suggest that motion perception plays an important role in the visual perception of driving-relevant hazards independent of other areas of visual function and should be further explored as a predictive test of driving safety. Future research should explore the causes of reduced motion perception in order to develop better interventions to improve road safety.

Evaluation of screening tests for predicting older driver performance and safety assessed by an on-road test

A number of tests and test batteries are available for the prediction of older driver safety, but many of these have not been validated against standardized driving outcome measures. The aim of this study was to evaluate a series of previously described screening tests in terms of their ability to predict the potential for safe and unsafe driving. Participants included 79 community-dwelling older drivers (M=72.16 years, SD=5.46; range 65-88 years; 57 males and 22 females) who completed a previously validated multi-disciplinary driving assessment, a hazard perception test, a hazard change detection test and a battery of vision and cognitive tests. Participants also completed a standardized on-road driving assessment. The multi-disciplinary test battery had the highest predictive ability with a sensitivity of 80% and a specificity of 73%, followed by the hazard perception test which demonstrated a sensitivity of 75% and a specificity of 61%. These findings suggest that a relatively simple and practical battery of tests from a range of domains has the capacity to predict safe and unsafe driving in older adults.

Quality of life detriments through self-reported swelling associated with gynaecological cancer

Background and aims: Lower-limb lymphoedema is a serious and feared sequela after treatment for gynaecological cancer. Given the limited prospective data on incidence of and risk factors for lymphoedema after treatment for gynaecological cancer we initiated a prospective cohort study in 2008. Methods: Data were available for 353 women with malignant disease. Participants were assessed before treatment and at regular intervals after treatment for two years. Follow-up visits were grouped into time-periods of six weeks to six months (time 1), nine months to 15 months (time 2), and 18 months to 24 months (time 3). Preliminary data analyses were undertaken up to time 2 using generalised estimating equations to model the repeated measures data of Functional Assessment of Cancer Therapy-General (FACT-G) quality of life (QoL) scores and self-reported swelling at each follow-up period (best-fitting covariance structure). Results: Depending on the time-period, between 30% and 40% of patients self-reported swelling of the lower limb. The QoL of those with self-reported swelling was lower at all time-periods compared with those who did not have swelling. Mean (95% CI) FACT-G scores at time 0, 1 and 2 were 80.7 (78.2, 83.2), 83.0 (81.0, 85.0) and 86.3 (84.2, 88.4), respectively for those with swelling and 85.0 (83.0, 86.9), 86.0 (84.1, 88.0) and 88.9 (87.0, 90.7), respectively for those without swelling. Conclusions: Lower-limb swelling adversely influences QoL and change in QoL over time in patients with gynaecological cancer.

The utility of serum CA-125 in predicting extra-uterine disease in apparent early stage endometrial cancer

Objectives: To evaluate the clinical value of pre-operative serum CA125 in predicting the presence of extra-uterine disease in patients with apparent early stage endometrial cancer. Methods: Between October 6, 2005 and June 17, 2010, 760 patients were enrolled in an international, multicentre, prospective randomized trial (LACE) comparing laparotomy with laparoscopy in the management of endometrial cancer apparently confined to the uterus. This study is based on data from 657 patients with endometrial adenocarcinoma who had a pre-operative serum CA125 value, and was undertaken to correlate pre-operative serum CA125 with final stage. Results: Using a pre-operative CA-125 cutpoint of 30U/ml was associated with the smallest misclassification error (14.5%) using a multiple cross-validation method. Median pre-operative serum CA-125 was 14U/ml, and using a cutpoint of 30U/ml, 14.9% of patients had elevated CA-125 levels. Of 98 patients with elevated CA-125 level, 36 (36.7%) had evidence of extra-uterine disease. Of the 116 patients (17.7%) with evidence of extra-uterine disease, 31.0% had elevated CA-125 level. In univariate and multivariate logistic regression analysis, only pre-operative CA-125 level was found to be associated with extra-uterine spread of disease. Utilising a cutpoint of 30U/ml achieved a sensitivity, specificity, positive predictive value and negative predictive value of 31.0%, 88.5%, 36.7% and 85.7% respectively. Overall, 326/657 (49.6%) of patients had full surgical staging involving lymph node dissection. When analysis was limited to patients that had undergone full surgical staging, the outcomes remained essentially unchanged. Conclusions: Elevated CA-125 above 30U/ml in patients with apparent early stage disease is associated with a sensitivity of 31.0% and specificity of 88.5% in detecting extra-uterine disease. Pre-operative identification of this risk factor may assist to triage patients to tertiary centres and comprehensive surgical staging.

Imagination in school children's choice of their learning environment: An Australian study

A visual research project addressed school children's concepts of ideal learning environments. Drawings and accompanying narratives were collected from Year 5 and Year 6 children in nine Queensland primary schools. The 133 submissions were analysed and coded to develop themes, identify key features and consider the uses of imagination. The children's imagined schools echo ideas promoted by progressive educators. The results of this study suggest benefits for school designers can emerge from the imaginative contributions of children in creating engaging environments, while educational policy makers can benefit from children's ideas in the promotion of engaging, student-centred pedagogies.

The children and sunscreen study : a crossover trial investigating children's sunscreen application thickness and the influence of age and dispenser type.

OBJECTIVES: To measure the thickness at which primary schoolchildren apply sunscreen on school day mornings and to compare it with the thickness (2.00 mg/cm(2)) at which sunscreen is tested during product development, as well as to investigate how application thickness was influenced by age of the child (school grades 1-7) and by dispenser type (500-mL pump, 125-mL squeeze bottle, or 50-mL roll-on). DESIGN: A crossover quasiexperimental study design comparing 3 sunscreen dispenser types. SETTING: Children aged 5 to 12 years from public primary schools (grades 1-7) in Queensland, Australia. PARTICIPANTS: Children (n=87) and their parents randomly recruited from the enrollment lists of 7 primary schools. Each child provided up to 3 observations (n=258). INTERVENTION: Children applied sunscreen during 3 consecutive school weeks (Monday through Friday) for the first application of the day using a different dispenser each week. MAIN OUTCOME MEASURE: Thickness of sunscreen application (in milligrams per square centimeter). The dispensers were weighed before and after use to calculate the weight of sunscreen applied. This was divided by the coverage area of application (in square centimeters), which was calculated by multiplying the children's body surface area by the percentage of the body covered with sunscreen. RESULTS: Children applied their sunscreen at a median thickness of 0.48 mg/cm(2). Children applied significantly more sunscreen when using the pump (0.75 mg/cm(2)) and the squeeze bottle (0.57 mg/cm(2)) compared with the roll-on (0.22 mg/cm(2)) (P<.001 for both). CONCLUSIONS: Regardless of age, primary schoolchildren apply sunscreen at substantially less than 1.00 mg/cm(2), similar to what has been observed among adults. Some sunscreen dispensers seem to facilitate thicker application than others.

Optimization of human papillomavirus type 16 (HPV-16) L1 expression in plants: Comparison of the suitability of different HPV-16 L1 gene variants and different cell-compartment localization

Virus-like particle-based vaccines for high-risk human papillomaviruses (HPVs) appear to have great promise; however, cell culture-derived vaccines will probably be very expensive. The optimization of expression of different codon-optimized versions of the HPV-16 L1 capsid protein gene in plants has been explored by means of transient expression from a novel suite of Agrobacterium tumefaciens binary expression vectors, which allow targeting of recombinant protein to the cytoplasm, endoplasmic reticulum (ER) or chloroplasts. A gene resynthesized to reflect human codon usage expresses better than the native gene, which expresses better than a plant-optimized gene. Moreover, chloroplast localization allows significantly higher levels of accumulation of L1 protein than does cytoplasmic localization, whilst ER retention was least successful. High levels of L1 (>17% total soluble protein) could be produced via transient expression: the protein assembled into higher-order structures visible by electron microscopy, and a concentrated extract was highly immunogenic in mice after subcutaneous injection and elicited high-titre neutralizing antibodies. Transgenic tobacco plants expressing a human codon-optimized gene linked to a chloroplast-targeting signal expressed L1 at levels up to 11% of the total soluble protein. These are the highest levels of HPV L1 expression reported for plants: these results, and the excellent immunogenicity of the product, significantly improve the prospects of making a conventional HPV vaccine by this means. © 2007 SGM.

Genetic analysis of maize streak virus isolates from Uganda reveals widespread distribution of a recombinant variant

Maize streak virus (MSV) contributes significantly to the problem of extremely low African maize yields. Whilst a diverse range of MSV and MSV-like viruses are endemic in sub-Saharan Africa and neighbouring islands, only a single group of maize-adapted variants - MSV subtypes A1 -A6 - causes severe enough disease in maize to influence yields substantially. In order to assist in designing effective strategies to control MSV in maize, a large survey covering 155 locations was conducted to assess the diversity, distribution and genetic characteristics of the Ugandan MSV-A population. PCR-restriction fragment-length polymorphism analyses of 391 virus isolates identified 49 genetic variants. Sixty-two full-genome sequences were determined, 52 of which were detectably recombinant. All but two recombinants contained predominantly MSV-A1-like sequences. Of the ten distinct recombination events observed, seven involved inter-MSV-A subtype recombination and three involved intra-MSV-A1 recombination. One of the intra-MSV-A1 recombinants, designated MSV-A1 UgIII, accounted for >60% of all MSV infections sampled throughout Uganda. Although recombination may be an important factor in the emergence of novel geminivirus variants, it is demonstrated that its characteristics in MSV are quite different from those observed in related African cassava-infecting geminivirus species. © 2007 SGM.

Inhibition of maize streak virus (MSV) replication by transient and transgenic expression of MSV replication-associated protein mutants

Maize streak disease is a severe agricultural problem in Africa and the development of maize genotypes resistant to the causal agent, Maize streak virus (MSV), is a priority. A transgenic approach to engineering MSV-resistant maize was developed and tested in this study. A pathogen-derived resistance strategy was adopted by using targeted deletions and nucleotide-substitution mutants of the multifunctional MSV replication-associated protein gene (rep). Various rep gene constructs were tested for their efficacy in limiting replication of wild-type MSV by co-bombardment of maize suspension cells together with an infectious genomic clone of MSV and assaying replicative forms of DNA by quantitative PCR. Digitaria sanguinalis, an MSV-sensitive grass species used as a model monocot, was then transformed with constructs that had inhibited virus replication in the transient-expression system. Challenge experiments using leafhopper-transmitted MSV indicated significant MSV resistance - from highly resistant to immune - in regenerated transgenic D. sanguinalis lines. Whereas regenerated lines containing a mutated full-length rep gene displayed developmental and growth defects, those containing a truncated rep gene both were fertile and displayed no growth defects, making the truncated gene a suitable candidate for the development of transgenic MSV-resistant maize. © 2007 SGM.

Identification of long intergenic region sequences involved in maize streak virus replication

The main cis-acting control regions for replication of the single-stranded DNA genome of maize streak virus (MSV) are believed to reside within an approximately 310 nt long intergenic region (LIR). However, neither the minimum LIR sequence required nor the sequence determinants of replication specificity have been determined experimentally. There are iterated sequences, or iterons, both within the conserved inverted-repeat sequences with the potential to form a stem-loop structure at the origin of virion-strand replication, and upstream of the rep gene TATA box (the rep-proximal iteron or RPI). Based on experimental analyses of similar iterons in viruses from other geminivirus genera and their proximity to known Rep-binding sites in the distantly related mastrevirus wheat dwarf virus, it has been hypothesized that the iterons may be Rep-binding and/or -recognition sequences. Here, a series of LIR deletion mutants was used to define the upper bounds of the LIR sequence required for replication. After identifying MSV strains and distinct mastreviruses with incompatible replication-specificity determinants (RSDs), LIR chimaeras were used to map the primary MSV RSD to a 67 nt sequence containing the RPI. Although the results generally support the prevailing hypothesis that MSV iterons are functional analogues of those found in other geminivirus genera, it is demonstrated that neither the inverted-repeat nor RPI sequences are absolute determinants of replication specificity. Moreover, widely divergent mastreviruses can trans-replicate one another. These results also suggest that sequences in the 67 nt region surrounding the RPI interact in a sequence-specific manner with those of the inverted repeat.

Hospital utilisation among people born in refugee-source countries : an analysis of hospital admissions, Victoria, 1998–2004

Objective: To investigate whether hospital utilisation and health outcomes in Victoria differ between people born in refugee-source countries and those born in Australia. Design and setting: Analysis of a statewide hospital discharge dataset for the 6 financial years from 1 July 1998 to 30 June 2004. Hospital admissions of people born in eight countries for which the majority of entrants to Australia arrived as refugees were included in the analysis. Main outcome measures: Age-standardised rates and rate ratios for: total hospital admissions; emergency admissions; surgical admissions; total days in hospital; discharge at own risk; hospital deaths; admissions due to infectious and parasitic diseases; and admissions due to mental and behavioural disorders. Results: In 2003–04, compared with the Australia-born Victorian population, people born in refugee-source countries had lower rates of surgical admission (rate ratio [RR], 0.85; 95% CI, 0.81–0.88), total days in hospital (RR, 0.74; 95% CI, 0.73–0.75), and admission due to mental and behavioural disorders (RR, 0.70; 95% CI, 0.65–0.76). Over the 6-year period, rates of total days in hospital and rates of admission due to mental and behavioural disorders for people born in refugee-source countries increased towards Australian-born averages, while rates of total admissions, emergency admissions, and admissions due to infectious and parasitic diseases increased above the Australian-born averages. Conclusions: Use of hospital services among people born in refugee-source countries is not higher than that of the Australian-born population and shows a trend towards Australian-born averages. Our findings indicate that the Refugee and Humanitarian Program does not currently place a burden on the Australian hospital system.