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This article describes the experiences of two trainee clinical psychologists in an inter-professional learning placement within a voluntary, communitybased service for refugees.

Diagnosis of colorectal cancer is an invasive and expensive colonoscopy, which is usually carried out after a positive screening test. Unfortunately, existing screening tests lack specificity and sensitivity, hence many unnecessary colonoscopies are performed. Here we report on a potential new screening test for colorectal cancer based on the analysis of volatile organic compounds (VOCs) in the headspace of faecal samples. Faecal samples were obtained from subjects who had a positive faecal occult blood sample (FOBT). Subjects subsequently had colonoscopies performed to classify them into low risk (non-cancer) and high risk (colorectal cancer) groups. Volatile organic compounds were analysed by selected ion flow tube mass spectrometry (SIFT-MS) and then data were analysed using both univariate and multivariate statistical methods. Ions most likely from hydrogen sulphide, dimethyl sulphide and dimethyl disulphide are statistically significantly higher in samples from high risk rather than low risk subjects. Results using multivariate methods show that the test gives a correct classification of 75% with 78% specificity and 72% sensitivity on FOBT positive samples, offering a potentially effective alternative to FOBT.

Selected ion flow tube mass spectrometry, SIFT-MS, has been used to monitor the volatile compounds in the exhaled breath of 30 volunteers (19 males, 11 females) over a 6 month period. Volunteers provided breath samples each week between 8:45 am and 1 pm (before lunch), and the concentrations of several trace compounds were obtained. In this paper the focus is on ammonia, acetone and propanol. It was found that the concentration distributions of these compounds in breath were close to log-normal. The median ammonia level estimated as a geometric mean for all samples was 833 parts per billion (ppb) with a multiplicative standard deviation of 1.62, the values ranging from 248 to 2935 ppb. Breath ammonia clearly increased with increasing age in this volunteer cohort. The geometric mean acetone level for all samples was 477 parts per billion (ppb) with a multiplicative standard deviation of 1.58, the values ranging from 148 to 2744 ppb. The median propanol level for all samples was 18 ppb, the values ranging from 0 to 135 ppb. A weak but significant correlation between breath propanol and acetone levels is apparent in the data. The findings indicate the potential value of SIFT-MS as a non-invasive breath analysis technique for investigating volatile compounds in human health and in the diseased state.

Summary This article shows how the CensusAtSchool project can be implemented in the classroom to make data handling much more real and relevant. It includes full lesson plans and notes on what the pupils achieved. Editor's Note The lesson plans for this article are provided in figure 4, which has been placed at the end of the article for convenience. The plans are based directly on CensusAtSchool material. Figure 4. Overview of Year 9 Project: Lesson Plans. Download figure to PowerPoint

The increase in ammonia and ethanol in the exhaled breath stream following mouthwashes by aqueous solutions of urea and sugar (sucrose), respectively, has been investigated by analysing exhaled breath in real time using selected ion flow tube mass spectrometry, SIFT-MS. It is shown that the measured levels of these compounds in the stream of exhaled breath can be much greater than the endogenous levels originating at the alveolar boundary. Thus, it is concluded that without careful preparation, mouth production of these compounds, and other compounds as yet unidentified, can seriously compromise the quantification of truly endogenous trace compounds present in blood and in the alveolar breath, as required for clinical diagnosis, and can probably introduce additional compounds into the breath stream that could seriously mislead breath analysis. The concentrations of both the urea and sucrose solutions used to enhance the ammonia and ethanol levels were larger than normally present in food and drinks and so in most situations such severe enhancements will not occur.

A sufficiently high composting temperature should inactivate many common pathogens likely to be present in solid animal waste. Monitoring core temperatures inside compost heaps is not straightforward, which means that heaps are not generally monitored. An alternative is to monitor surface temperatures and use those data to infer core temperatures, and thus whether pathogen inactivation has occurred. This paper describes two methods (thermal imaging and thermocouples) for the measurement of surface temperature, and a modelling approach using time series analysis to predict the temperatures obtained in the core of aerated heaps of composting pig farmyard manure (FYM) from surface temperature data. The model was able to predict core temperatures in the heap quite closely for a period of time for well insulated parts of the heap, although predictions were further from observed values close to the surface of the heap and the aeration pipe.

Selected-ion flow-tube mass spectrometry (SIFT-MS) has been used to monitor the volatile compounds in the exhaled breath of 30 volunteers (19 male, 11 female) over a 6-month period. Volunteers provided breath samples each week between 8:45 and 13:00 (before lunch), and the concentrations of several trace compounds were obtained. In this paper the focus is on ethanol and acetaldehyde, which were simultaneously quantified by SIFT-MS using H3O+ precursor ions. The mean ethanol level for all samples was 196 parts-per-billion (ppb) with a standard deviation of 244 ppb, and the range of values for breath samples analysed is 0 to 1663 ppb. The mean acetaldehyde level for all samples was 24 ppb with a standard deviation of 17 ppb, and the range of values for breath samples analysed is 0 to 104 ppb. Background (ambient air) levels of ethanol were around 50 ppb, whereas any background acetaldehyde was usually undetectable. Increased ethanol levels were observed if sweet drink/food had been consumed within the 2 h prior to providing the breath samples, but no increase was apparent when alcohol had been consumed the previous evening. The measured endogenous breath ethanol and acetaldehyde levels were not correlated. These data relating to healthy individuals are a prelude to using breath analysis for clinical diagnosis, for example, the recognition of bacterial overload in the gut (ethanol) or the possibly of detecting tumours in the body (acetaldehyde).

The photochemistry of Ru(etp)(CO)H2 (1, etp = PhP(CH2CH2PPh2)2) has been studied by UV/vis spectroscopy following nanosecond laser flash photolysis and by NMR and IR spectroscopy following steady-state irradiation. Steady-state irradiation under CO, C2H4, and Et3SiH yields Ru(etp)(CO)2, Ru(etp)(CO)(C2H4), and Ru(etp)(CO)(SiEt3)H, respectively. Laser flash photolysis (laser wavelength 308 nm) of 1 in cyclohexane generates the 16-electron transient Ru(etp)(CO). In the absence of additional ligands, Ru(etp)(CO) decays by reaction with photoejected dihydrogen, regenerating 1. When flash photolysis was performed in the presence of added ligands, the transient decays by pseudo-first-order kinetics with second-order rate constants on the order of 108 dm3 mol-1 s-1. However, the fastest reaction rate (H2) is only a factor of ca. 4 greater than the slowest (Et3SiH). Activation parameters for the reaction of 1 with Et3SiH were determined as ΔG298⧧ = 25.7 ± 0.1 kJ mol-1, ΔH⧧ = 11 ± 1 kJ mol-1, and ΔS⧧ = −49 ± 4 J mo...

The rate at which oxygen is consumed during composting is a measure of aerobic microbial activity and is linked to the rate of organic material decomposition. The rate of loss in mass is a function of the mass of the degradable organic fraction and is related to oxygen uptake rate by the reaction rate coefficient, k. The decomposition of a pig manure and straw mix was investigated at temperatures between 10°C and 70°C using respirometric techniques. The oxygen concentrations in the reactor were measured continuously for about 4 days and then converted to hourly oxygen uptake rates for each incubation temperature, T. The specific oxygen uptake rate was used to calculate the reaction rate coefficient at T, kT, for the observed fast and slow stages of decomposition. The effect of the environmental factors was taken into account using a multiplicative approach and a relationship, which expressed kT for each stage as a function of T, was formulated. The maximum measured rate of activity occurred during the fas...

An electronic tongue comprising 21 potentiometric chemical sensors with pattern recognition tools was used for the rapid off-line monitoring of batch Escherichia coli fermentations. The electronic tongue was capable of monitoring the changes in the media composition as the fermentation progressed, and could correlate this with an increase in biomass. The electronic tongue was also able to monitor the increase in organic acids, especially acetic acid, throughout the fermentation. This technique clearly shows promise as a rapid tool for fermentation monitoring.

This article gives an overview of an existing behaviour policy of a mixed comprehensive school in Stevenage, Hertfordshire. It discusses the procedures undertaken in writing the original policy, and highlights the necessity of involving the whole school community in its development. The article examines the risks of failing to involve all staff and pupils in the development of a behaviour policy, and the inconsistencies in practice that arise when those using the policy have no ownership of the document. The article discusses the need for regular reviews of the policy and the importance of inducting new staff thoroughly so as to maintain consistency in the policy's application. Finally, the article examines the impact of insufficient differentiation and the need for inclusion for pupils with special educational needs, across the spectrum.

Proton Transfer Reaction Mass Spectrometry (PTR-MS) is a well-established technique for real-time VOCs (Volatile Organic Compounds) analysis. Although, it is extremely sensitive (with sensitivities of up to 4500 cps/ppbv, limits of the detection < 1 pptv and the response times of approximately 100 ms) the selectivity of PTR-MS is still somewhat limited, as isomers cannot be separated. Recently, selectivity-enhancing measures, such as manipulation of drift tube parameters (reduced electric field strength) and using primary ions other than H3O+, such as NO+ and O2+ have been introduced. However, monoterpenes, which belong to the most important plant VOCs, still cannot be distinguished so that more traditional technologies, such as gas chromatography mass spectrometry (GC-MS), have to be utilized. GC-MS is very time consuming (up to 1 h) and cannot be used for real-time analysis. \ud Here we introduce a sensitive, near real-time method for plant monoterpene research: PTR-MS coupled with fastGC. We successfully separated and identified six of the most abundant monoterpenes in plant studies (α- and β-pinenes, limonene, 3-carene, camphene, and myrcene) in less than 80 s, using both standards and conifer branch enclosures (Norway spruce, Scots pine and Black pine). Five monoterpenes usually present in Norway spruce samples with a high abundance were separated even when the compound concentrations were diluted to 20 ppbv. Thus, fastGC-PTR-ToF-MS was shown to be an adequate one-instrument solution for plant monoterpene research.

Aims The primary objective of the study was to assess the residual effects of zaleplon in the morning, 4 h after a middle-of-the-night administration. The secondary objective was to investigate the effectiveness of zaleplon in promoting sleep in healthy volunteers with noise-induced sleep maintenance insomnia. Methods Thirteen healthy male and female volunteers (aged 20–30 years) with normal hearing, who were sensitive to the sleep-disrupting effects of noise, participated in a double-blind, placebo- and active-drug controlled, four-period cross-over study. The subjects were permitted to sleep for 5 h (22.45–03.45 h) in a quiet environment before they were awoken. At 04.00 h they ingested 10 mg zaleplon, 20 mg zaleplon, 7.5 mg zopiclone (active control), or placebo before a second period of sleep (04.00–08.00 h), during which they were exposed to an 80 dB(A) 1 kHz pure tone pulse with an inter-tone interval of 1 s and a duration of 50 ms. The sound stimulus was stopped after 10 min of persistent sleep or after 2 h if the subject had not fallen asleep. Residual effects were assessed at 08.00 h (4 h after drug administration) using the digit symbol substitution test (DSST), choice reaction time (CRT), critical flicker fusion (CFF), and immediate and delayed free recall of a 20 word list. The data were analysed by analysis of variance. A Bonferroni adjustment was made for the three active treatments compared with placebo. Results There were no residual effects of zaleplon (10 and 20 mg) compared with placebo. Zopiclone impaired memory by delaying the free recall of words (P = 0.001) and attenuated performance on DSST (P = 0.004) and CRT (P = 0.001), compared with placebo. Zaleplon reduced the latency to persistent sleep (10 mg, P = 0.001; 20 mg, P = 0.014) and the 20 mg dose reduced stage 1 sleep (P = 0.012) compared with placebo. Zopiclone reduced stage 1 sleep (P = 0.001), increased stage 3 sleep (P = 0.0001) and increased total sleep time (P = 0.003), compared with placebo. Conclusions Zaleplon (10 mg and 20 mg), administered in the middle of the night 4 h before arising, shortens sleep onset without impairing next-day performance.

It is well understood that weaknesses in process safety management can lead to major accidents with the potential for catastrophic consequences. These weaknesses typically develop overtime due to the cumulative effect of changes in the integrity of equipment and the quality of operating practice. Such changes often go unchallenged and uncorrected as a result of complacency and what has been referred to as the normalization of deviation. Combating the slow decline and drift into failure requires the establishment of a more effective culture of process safety management. The crucial element of this culture is the identification of safety critical tasks that are essential to the maintenance and assurance of technical safety barriers. In all hazardous systems, people are responsible for the maintenance, calibration and testing of process safety control or barrier measures. Comprehensively identifying these safety critical tasks and defining the organizational management processes that are necessary to assure their successful completion, lays the foundation for a culture of effective process safety management. It also creates the opportunity to establish leading indications of process safety and avoid relying on lagging indications which only signal the failure to control risk. This paper presents examples of how human and organizational failures can contribute to a gradual drift into failure resulting in major accident events. It then shows how the human role in maintaining and assuring the reliability of built-in safety measures can be assessed and verified for both new assets and mature operations. The methodology demonstrated is an integrated approach to process safety and human factors and shows how the approach can be applied to create leading indications of effective process safety management that delivers both technical safety and an improved safety culture.

Monitoring blood glucose concentrations is a necessary but tedious task for people suffering from diabetes. It has been noted that breath in people suffering with diabetes has a different odour and thus it may be possible to use breath analysis to monitor the blood glucose concentration. Here, we evaluate the analysis of breath using a portable device containing a single mixed metal oxide sensor during hypoglycaemic glucose clamps and compare that with the use of SIFT-MS described in previously published work on the same set of patients. Outputs from both devices have been correlated with the concentration of blood glucose in eight volunteers suffering from type 1 diabetes mellitus. The results demonstrate that acetone as measured by SIFT-MS and the sensor output from the breath sensing device both correlate linearly with blood glucose; however, the sensor response and acetone concentrations differ greatly between patients with the same blood glucose. It is therefore unlikely that breath analysis can entirely replace blood glucose testing.

This paper has been written from the perspective of John, a year 9 pupil with emotional and behavioural difficulties. The intention of the research was to gain a clearer understanding of the factors affecting John's behaviour, and consequently, his learning. The research indicates that it is primarily the breakdown of the teacher‐pupil relationship that affects John's behaviour. Other factors include his need to communicate with peers and his poor concentration span. The research demonstrates the importance of gaining pupil perception and acting on this information when differentiating in the learning environment to include pupils with emotional and behavioural difficulties.

OBJECTIVE To establish the effect of melatonin upon nocturnal and evening sleep. METHODS Experiment I: The effect of melatonin (0.1, 0.5, 1.0, 5.0, and 10 mg), ingested at 23:30, was studied on nocturnal sleep (23:30-07:30) and core body temperature in 8 healthy volunteers. Performance was measured 8.5 h post-ingestion. On completion of the experiment dim light melatonin onsets (DLMO) were determined. Experiment II: The effect of melatonin (0.5, 1.0, 5.0, and 10 mg), ingested at 18:00, was studied on evening sleep (18:00-24:00) and core body temperature in 6 healthy volunteers. Performance was measured 6.5 h post-ingestion. Each experiment was placebo-controlled and double-blind with a cross-over design with temazepam (20 mg) as an active control. RESULTS Experiment I: Melatonin (5 mg) reduced the duration of stage 3 in the first 100 min of sleep. Melatonin (0.1 mg) reduced body temperature 6.5 to 7 h post-ingestion. Temazepam increased stage 2, reduced wakefulness and stage 1, and increased the latency to REM sleep. Temazepam reduced body temperature 4.5 to 6.5 h post-ingestion. There were no changes in performance compared with placebo. DLMO occurred between 20:40 and 23:15. Experiment II: Melatonin (all doses) increased total sleep time (TST), sleep efficiency index (SEI) and stage 2, and reduced wakefulness. Temazepam increased TST, SEI, stage 2 and slow-wave sleep, and reduced wakefulness. There were no changes in body temperature or performance compared with placebo. CONCLUSION Melatonin given at 23:30 has no significant clinical effect on nocturnal sleep in healthy individuals. Hypnotic activity of melatonin when given in the early evening (presumably in the absence of endogenous melatonin) is similar to 20 mg temazepam.

This paper describes a pilot scale treatment plant that has been designed and built for the thermal inactivation in pig slurry of two viruses that infect pigs--African swine fever virus (ASFV) and swine vesicular disease virus (SVDV). The plant treats pig slurry continuously at a rate of up to 100 litres/hour and functions by heating the slurry, maintaining at least 99.99% of the slurry at the required temperature for a minimum period of 5 minutes, and then recovering the heat to raise the temperature of the incoming slurry. Results obtained indicated that SVDV was inactivated in pig slurry to below detectable levels with an alkaline pH (pH 7.5 to 8, as is usually the case) at a temperature of between 50 and 55 degrees C. In acidified slurry (pH 6.4), inactivation occurred between 55 and 60 degrees C. The difference in inactivation temperatures was probably due to the presence of free ammonia in the unacidified slurry. ASFV was inactivated by operating the plant at a temperature of 53 degrees C at a pH of 8.

Methyl viologen (MV) has been incorporated into paper as an aqueous solution and in the viscous electrolyte polyAMPS, and the availability of the MV for electron-transfer has been investigated by cyclic voltammetry at a stationary platinum disc electrode. In this study, which is the first rigorous study of an electrochrome in paper, the variables of choice were scan rate, relative humidity and electrolyte composition. The implications of the incorporation of MV into paper are discussed in terms of electrochromism. It is concluded that (i) electrochemical generation of colour in the paper is feasible; (ii) the rate of colour formation in paper is likely to be very slow; (iii) the MV2+, MV+· couple is fully electroactive in paper but (iv) the MVo redox state is best avoided since its immediate product, a spin-paired radical–cation dimer formed via comproportionation, is slightly electro-inactive. Dimer also complicates the electrochemical interpretations.

This review discusses a number of possible treatments for pathogen disinfection and evaluates them for their applicability in inactivating viruses in either dilute or concentrated pig slurry, particularly on a large scale. Methods are discussed under the headings of chemical, physical and other treatments. From those methods considered, it appears that the most suitable treatments are the use of heat at about 60°C for up to 30 min, or the application of an appropriate concentration of chemical, such as sodium or calcium hydroxides, or formalin. Aerobic and anaerobic treatments are also known to have virucidal effects, and could be used to assist decontamination on farms where such technologies are already used in routine slurry treatment.

The duration of activity of modafinil was investigated in healthy male volunteers in two double-blind crossover studies. Mode of action was explored using a statistical model concerned with the relationship between total sleep duration and that of rapid eye movement (REM) sleep. Nocturnal sleep (23:00–07:00) followed by next-day performance (09:00–17:00) was studied in 12 subjects administered 100, 200, 300 mg modafinil and placebo, 0.5 h before bedtime. Performance overnight (19:00–08:45) followed by sleep (09:15–15:15) was studied in nine subjects administered 100, 200, 300, 400 mg modafinil, 300 mg caffeine and placebo at 22:15. Modafinil dose-dependently reduced sleep duration (nocturnal: 200 mg, p100 mg; 300, 400 mg>200, 100 mg, caffeine). However, in the study of next-day performance, the enhancement was attenuated at the highest dose (300 mg) by the greater disturbance of prior sleep. These findings indicate that modafinil has a long duration of action, with alerting properties arising predominantly from dopaminergic activity.

The relative abundance of different groups of sulphate-reducing bacteria (SRB) in faecal DNA collected before and after therapy from patients suffering from Crohn's disease (CD), irritable bowel syndrome (IBS) or ulcerative colitis (UC) has been compared with that from healthy controls. Growth tests revealed that SRB were not more abundant in samples from patients with CD before treatment than in the healthy control group. For most of the 128 samples available, these preliminary results were confirmed using degenerate PCR primers that amplify the dsrAB gene. However, some samples from patients with CD before treatment contained a growth inhibitor that was absent from IBS or UC samples. In-depth sequencing of PCR-generated dsrB fragments revealed that the diversity detected was surprisingly low, with only eight strains of SRB and the sulphite-reducing bacterium, Bilophila wadsworthia, detected above the 0.1% threshold. The proportion of the two major species detected, B. wadsworthia and Desulfovibrio piger, was as high as 93.5% of the total SRB population in the healthy control group and lower in all patient groups. Four previously undescribed species were found: it is impossible to predict whether they are sulphate or sulphite-reducing bacteria.

The ability to monitor blood glucose noninvasively has long been a goal of those with diabetes, due to the pain and inconvenience of current blood glucose monitoring devices. This article investigates the potential for monitoring compounds in breath and emitted through skin for inferring blood glucose concentration. Potential markers and an assessment of their suitability for noninvasive monitoring are discussed. The varying technologies developed for monitoring volatile organic compounds in breath and from the skin of diabetics and their suitability for development as a hand-held device is reviewed. The potential exists for the use of breath and skin monitoring as an alternative to blood glucose, but it may take years to collect sufficient clinical data for robust correlations to be possible.

The published results of breath isoprene studies, to date largely involving adults, are briefly reviewed with special attention given to the work done on this topic during the last 10 years using selected ion flow tube mass spectrometry, SIFT-MS. Then the new data recently obtained on isoprene levels in the exhaled breath of some 200 healthy children and young adults (pupils) with ages ranging from 7 to 18 years measured using SIFT-MS are presented in detail. A concentration distribution has been constructed from the data obtained and compared to that for healthy adults also obtained from SIFT-MS data. Although there is overlap between the two distributions, which are close to log normal in both cases, the median level for the young cohort is much lower at 37 parts-per-billion, pbb, geometric standard deviation, GSD, 2.5, compared to that for the adult cohort of 106 ppb with a GSD of 1.65. Further to this, there is a clear increase in the mean breath isoprene concentration with age for the young cohort with a doubling of the level about every 5-6 years until it reaches the age-invariant mean level of that for adult cohort. Should this trend be extrapolated downwards in age it would indicate a near-zero breath isoprene in the newborn that was indicated by a previous study. Indeed, in the present study isoprene was not detected on the breath of two young children. The results reveal mean breath isoprene levels (±SD) for pupils within the given age ranges as 7-10 years (28 ± 24 ppb), 10-13 years (40 ± 21 ppb), 13-16 years (60 ± 41 ppb) and 16-19 years (54 ± 31 ppb). The more rapid increase that occurs between the second and third age ranges is statistically highly significant (p = 0.001) and we attribute this phenomenon to the onset of puberty and the spurt in growth that occurs during this phase of development. There is no significant difference in mean breath isoprene between males and females for both the adult cohort and the younger cohort.

Previous studies have indicated that volatile compounds specific to bladder cancer may exist in urine headspace, raising the possibility that headspace analysis could be used for diagnosis of this particular cancer. In this paper, we evaluate the use of a commercially available gas sensor array coupled with a specifically designed pattern recognition algorithm for this purpose. The best diagnostic performance that we were able to obtain with independent test data provided by healthy volunteers and bladder cancer patients was 70% overall accuracy (70% sensitivity and 70% specificity). When the data of patients suffering from other non-cancerous urological diseases were added to those of the healthy controls, the classification accuracy fell to 65% with 60% sensitivity and 67% specificity. While this is not sufficient for a diagnostic test, it is significantly better than random chance, leading us to conclude that there is useful information in the urine headspace but that a more informative analytical technique, such as mass spectrometry, is required if this is to be exploited fully.

This study aimed (i) to assess the ability of electronic nose (e-nose) technology to differentiate between blood samples of experimentally infected and non-infected subjects, and (ii) to evaluate e-nose responses given by volatile organic compounds in relation to the acute phase reaction generated in the host. In an animal model of gram-negative bacterial infection (20 calves; intratracheal inoculation of Mannheimia haemolytica A1), the concentrations of the acute phase proteins (APPs; i.e. lipopolysaccharide binding protein and haptoglobin) were measured in serum samples before and after challenge, and headspaces of pre- and post-inoculation serum samples were analysed using a conducting polymer based e-nose. Significant changes of certain e-nose sensor responses allowed discrimination between samples before and after challenge. The maximal changes in responses of sensitive e-nose sensors corresponded to the peak of clinical signs. Significant correlations linked decreasing responses of multiple e-nose sensors to increasing concentrations of APPs in the peripheral blood.

The currently accepted 'gold standard' tuberculosis (TB) detection method for veterinary applications is that of culturing from a tissue sample post mortem. The test is accurate, but growing Mycobacterium bovis is difficult and the process can take up to 12 weeks to return a diagnosis. In this paper we evaluate a much faster screening approach based on serum headspace analysis using selected ion flow tube mass spectrometry (SIFT-MS). SIFT-MS is a rapid, quantitative gas analysis technique, with sample analysis times of as little as a few seconds. Headspace from above serum samples from wild badgers, captured as part of a randomised trial, was analysed. Multivariate classification algorithms were then employed to extract a simple TB diagnosis from the complex multivariate response provided by the SIFT-MS instrument. This is the first time that such multivariate analysis has been applied to SIFT-MS data. An accuracy of TB discrimination of approximately 88% true positive was achieved which shows promise, but the corresponding false positive rate of 38% indicates that there is more work to do before this approach could replace the culture test. Recommendations for future work that could increase the performance are therefore proposed.

Electronic noses (e‐noses) have been widely used for medical applications or in the food industry. However, little is known about their utility for early disease detection in animals. In this study, 20 calves were experimentally infected with Mannheimia haemolytica A1. Blood serum was collected from 7 days before infection to 5 days after infection and headspace of sera was analysed using the ST214 (Scensive Tech. Ltd., Leeds, UK) e‐nose. Differences between pre‐ and post infection status were investigated and a temporal profile of sensor responses was compared with body temperature over the course of infection. A similar profile for sensor responses and body temperature indicated the e‐nose was detecting a genuine physiological response following infection.

A proof of concept investigation was performed to demonstrate that two independent infectious diseases of cattle result in different patterns of volatile organic compounds (VOC) in the headspace of serum samples detectable using an electronic nose (e‐nose). A total of 117 sera from cattle naturally infected with Mycobacterium avium subsp. paratuberculosis (paraTB, n = 43 ) or Brucella sp. ( n = 26) and sera from corresponding control animals ( n = 48) were randomly and analysed blind to infection status using a ST214 e‐nose (Scensive Ltd, Leeds, UK). Samples were collected under non‐standardised conditions on different farms from the UK (brucellosis) and Germany (paraTB). The e‐nose could differentiate the sera from brucellosis infected, paraTB infected and healthy animals at the population level, but the technology used was not suitable for determination of the disease status of individual animals. Nevertheless, the data indicate that there are differences in the sensor responses depending on the disease status, and therefore, it shows the potential of VOC analysis from serum headspace samples for disease detection.

Since the idea of electronic noses was published, numerous electronic nose (e‐nose) developments and applications have been used in analyzing solid, liquid and gaseous samples in the food and automotive industry or for medical purposes. However, little is known about methodological pitfalls that might be associated with e‐nose technology. Some of the methodological variation caused by changes in ambient temperature, using different filters and changes in mass flow rates are described. Reasons for a lack of stability and reproducibility are given, explaining why methodological variation influences sensor responses and why e‐nose technology may not always be sufficiently robust for headspace analysis. However, the potential of e‐nose technology is also discussed.

Conventional wisdom is that breath acetone may be markedly elevated in type 1 diabetes, but that this only occurs during poor blood glucose control and/or intercurrent illness. In contrast, little is known about breath acetone at more representative everyday blood glucose levels in diabetes. We used selected ion flow tube mass spectrometry (SIFT-MS) to monitor the breath of 8 patients with type 1 diabetes mellitus during “insulin clamp” studies in which insulin and glucose were infused into patients to lower blood glucose levels in steps from normal values into the low glucose (hypoglycaemic) range. The concentration of acetone in breath and the blood sugar concentration of the patients were monitored at each blood glucose concentration. The blood glucose level at the start of the study was typically about 6mM/L, whereas the breath acetone concentration at this blood glucose level was unexpectedly variable, ranging from one part-per-million (ppm) to 21 ppm, in contrast to what was previously believed, i.e. that type 1 diabetes mellitus (T1DM) is characterised by high acetone levels. In all 8 patients, the breath acetone declined linearly with blood glucose concentration.

The prevalence of type 2 diabetes is rising rapidly.1 More than 240 million people worldwide are estimated to have diabetes, and this number is likely to reach over 360 million by 2030.1 2 The impact on health occurs primarily through cardiovascular disease, but younger age of onset and advances in the prevention of cardiovascular disease are increasingly exposing people to the risks of microvascular damage, such as kidney and eye disease.1 The management of diabetes is complex and needs to address the prevention of cardiovascular disease and microvascular disease and the detection and management of early vascular complications.3 In recent years new evidence has accumulated on lifestyle intervention, self management through education, and self monitoring, and many new treatments have been introduced for various aspects of management. This article summarises the recommendations from an updated guideline by the National Institute for Health and Clinical Excellence (NICE) on the management of type 2 diabetes.4 NICE recommendations are based on systematic reviews of best available evidence. When minimal evidence is available, recommendations are based on the opinion of the Guideline Development Group (GDG) of what constitutes good practice. Evidence levels for the recommendations are given in italic in square brackets. ### Patient centred care

This study examined the utilization patterns of key Carbon sources (CS, 24: including key sugars, aminoacids and fatty acids) in maize by strains of Aspergillus flavus and Fusarium verticillioides under different water activity (aw, 0.87-0.98 aw) and temperature (20-35°C) values and compared the niche overlap indices (NOI) that estimate the in vitro carbon source utilization profiles (Wilson and Lindow, 1994). The ability to grow in these key CS in minimal media was studied for 120 hrs in 12 hr steps. The NOI was calculated for inter-species (F. verticillioides – A. flavus) and for intra-species (A. flavus - A. flavus) using CS utilisation patterns over the range of interacting environmental conditions. 30°C, over the whole aw range examined, was found to be optimal for utilization of the maximum number of CS by A. flavus. In contrast, for F. verticillioides this was more so at 20°C; 25°C allowed a suboptimal usage of CS for both species. NOIs confirmed the nutritional dominance of A. flavus at 30°C, especially at lower aw levels and that of F. verticillioides at 20°C, mainly at 0.95 aw. In other conditions of aw, based on CS utilization patterns, the data indicated that A. flavus and F. verticillioides occupied different ecological niches. The variability in nutritional sources utilization between A. flavus strains was not related to their ability to produce aflatoxins (AFs). This type of data helps to explain the nutritional dominance of fungal species and strains under different environmental conditions. This could be useful in trying to find appropriate natural biocontrol microorganisms to compete with these mycotoxigenic

Plants are a major atmospheric source of volatile organic compounds (VOCs). These secondary metabolic products protect plants from high-temperature stress, mediate in plant–plant and plant–insect communication, and affect our climate globally. The main challenges in plant foliar VOC research are accurate sampling, the inherent reactivity of some VOC compounds that makes them hard to detect directly, and their low concentrations. Plant VOC research relies on analytical techniques for trace gas analysis, usually based on gas chromatography and soft chemical ionization mass spectrometry. Until now, these techniques (especially the latter one) have been developed and used primarily by physicists and analytical scientists, who have used them in a wide range of scientific research areas (e.g., aroma, disease biomarkers, hazardous compound detection, atmospheric chemistry). The interdisciplinary nature of plant foliar VOC research has recently attracted the attention of biologists, bringing them into the field of applied environmental analytical sciences. In this paper, we review the sampling methods and available analytical techniques used in plant foliar VOC research to provide a comprehensive resource that will allow biologists moving into the field to choose the most appropriate approach for their studies.

Selected ion flow tube mass spectrometry, SIFT-MS, has been used to monitor the volatile compounds in the exhaled breath of 30 volunteers (19 male, 11 female) over a six-month period. Volunteers provided breath samples each week between 8:45 am and 1 pm (before lunch), and the concentrations of several trace compounds were obtained. In this paper the focus is on methanol in breath. The median methanol level determined using the H(3)O(+) precursor ions for all samples was 461 parts-per-billion (ppb), the concentrations for all the samples ranging from 32 to 1684 ppb. The distribution of breath methanol concentration is seen to be log-normal for this healthy population; the geometric mean was 450 ppb, close to the median value, and the multiplicative (geometric) standard deviation was 1.62. Breath methanol is not correlated with age, breath ethanol or ethanol consumed in the previous 24 h, but there was an inverse correlation with body mass index (BMI) for the cohort of volunteers recruited for this study. Observed breath methanol levels are well compatible with the previously published blood methanol levels. Some tentative suggestions are made concerning the origin of endogenous methanol.

The influence of sedation on the effect of an H-1 receptor antagonist on various cognitive functions, including memory, were evaluated. Diphenhydramine (50, 75 and 100mg) and lorazepam (0.5 and 1.5mg) were given on single occasions to 12 healthy volunteers (six males, six females) aged 20–33 (mean 23.4) years. Subjective assessments of sedation, sleep latencies, digit symbol substitution, choice reaction time, sustained attention and memory recall were studied 1.0h before and 0.5, 2.0 and 3.5h after drug ingestion. The study was double blind, placebo controlled and with a crossover design. With all doses of diphenhydramine there was subjective sedation, reduced sleep latencies and impairments in performance on the digit symbol substitution, choice reaction time and sustained attention tasks. No effects were observed with 0.5mg lorazepam. With 1.5mg lorazepam there was subjective sedation, fewer digit symbol substitutions, slowed choice reaction time, impaired attention and memory, but no effect on sleep latencies. Contrast analysis of data measured at all time points showed that although there was no difference in the effect of diphenhydramine (100mg) and lorazepam (1.5mg) on those tasks without a memory component, response times were slower with lorazepam on those tasks with a memory component. However, both 100mg diphenhydramine and 1.5mg lorazepam impaired prompted recall measured at 2h post-ingestion only. It is considered that impaired memory is not necessarily associated with sedation, and that impairment of memory with drugs that lead to sedation may be effected through neuronal systems independent of those that affect arousal.

Thirty volunteers (19 males, 11 females) were recruited for a 6-month study of the volatile compounds in their exhaled breath using the selected ion flow tube mass spectrometry (SIFT-MS) analytical technique. Volunteers provided weekly breath samples between 8:45 am and 1 pm (before lunch), and the concentrations of several trace compounds were obtained. In this paper, we focus on the isoprene in alveolar breath, which was monitored by SIFT-MS using NO(+) precursor ions. The mean isoprene level for all samples was 118 parts per billion (ppb) with a standard deviation of 68 ppb and the range of values for breath samples given is 0-474 ppb. Variability in isoprene levels was similar in most volunteers. Isoprene levels increased immediately after moderate exercise, but returned to normal within 2-3 min for those few volunteers that were investigated. Cholesterol levels analysed for only three of the subjects were not obviously correlated with isoprene concentration in breath. Differences in isoprene levels were not directly correlated to gender, age or body mass index.

Air operations may demand missions of many hours, and aircrew may experience significant discomfort due to bladder distension. Attention has been given to the use of in-flight urination devices, but an alternative strategy could be reduction of urine flow by an anti-diuretic. In this event it would be important to establish an effective dose range free of adverse effects.The effects of desmopressin (0.05, 0.10, 0.15, and 0.20 mg) on cognitive performance and sleepiness (multiple sleep latency test) from 1 to 11 h, and on urine flow up to 24 h after drug ingestion at 09:00, were studied in 20 healthy young volunteers. The study was double blind, placebo controlled, and with a randomized five-way crossover design.There was no evidence of impaired performance with desmopressin at or below 0.15 mg. All doses reduced urine flow up to 12 h after drug ingestion (p0.001), and the reduction appeared to be maximal at 0.10 mg. The dose range was free of adverse effects, except for the possibility of headaches, but they are unlikely to be of operational significance.Desmopressin could prove to be a significant advance in the management of urinary flow in operational aircrew. The dose could be as low as 0.05 mg with the option to use 0.10 mg in those less sensitive to the drug. Individual experience of the effect of the drug would be appropriate before use in flight, and guidelines concerning fluid intake would be needed. Further information may be required for use of the drug overnight.

The effects of cannabis extracts on nocturnal sleep, early-morning performance, memory, and sleepiness were studied in 8 healthy volunteers (4 males, 4 females; 21 to 34 years). The study was double-blind and placebo-controlled with a 4-way crossover design. The 4 treatments were placebo, 15 mg Delta-9-tetrahydrocannabinol (THC), 5 mg THC combined with 5 mg cannabidiol (CBD), and 15 mg THC combined with 15 mg CBD. These were formulated in 50:50 ethanol to propylene glycol and administered using an oromucosal spray during a 30-minute period from 10 pm. The electroencephalogram was recorded during the sleep period (11 pm to 7 am). Performance, sleep latency, and subjective assessments of sleepiness and mood were measured from 8:30 am (10 hours after drug administration). There were no effects of 15 mg THC on nocturnal sleep. With the concomitant administration of the drugs (5 mg THC and 5 mg CBD to 15 mg THC and 15 mg CBD), there was a decrease in stage 3 sleep, and with the higher dose combination, wakefulness was increased. The next day, with 15 mg THC, memory was impaired, sleep latency was reduced, and the subjects reported increased sleepiness and changes in mood. With the lower dose combination, reaction time was faster on the digit recall task, and with the higher dose combination, subjects reported increased sleepiness and changes in mood. Fifteen milligrams THC would appear to be sedative, while 15 mg CBD appears to have alerting properties as it increased awake activity during sleep and counteracted the residual sedative activity of 15 mg THC.

The purpose of this study was to establish whether the H1-antihistamine desloratadine (5 mg), the active metabolite of loratadine, is free of effects on performance and sleepiness.Effects of desloratadine (5 mg) on psychomotor performance, daytime sleep latencies, subjective sleepiness, and memory were studied in nine healthy volunteers (four men, five women) between the ages of 20 and 39 yr (mean 28.2). Assessments were made 1.0 h pre-ingestion and from 0.5 to 8.0 h post-ingestion. The study was placebo-controlled and double blind with a crossover design, using promethazine (25 mg) as an active control.Promethazine impaired tracking (3.5-5.5 h), choice reaction time (3.5-5.5 h), digit symbol substitution (3.5-5.5 h), and attention (2.0-5.5 h). There was increased objective and subjective sleepiness (2.0-5.5 h) and subjective fatigue (3.5-8.0 h). There were no changes in any of these measures with desloratadine (5 mg). With promethazine, memory was impaired from 2.0-5.0 h. Analysis failed to establish a consistent effect on memory with desloratadine, as there was a change in only one (digit memory recall reaction time) of the twelve memory test measures at only one time point (5.5 h). The change was significant with respect to placebo, but not with respect to the pre-ingestion value.Desloratadine (5 mg) appears to be free of adverse effects on psychomotor performance, daytime sleep latencies, and subjective sleepiness, and could prove suitable for those involved in skilled activity and transportation.