Field trials of a methodology for locomotive brake testing to assess friction enhancement in the wheel/rail interface using a representative leaf layer

There are two options for testing the performance of rail vehicles and the application of material to the wheel/rail interface to influence friction, and therefore braking performance, in a low adhesion environment: laboratory work which is not representative of conditions in the field, and expensive track tests using fully instrumented modern vehicles largely using low adhesion simulants that are not representative of those that occur in the real world and usually applied over great lengths of track. This paper presents a third option: low-cost track tests. We determined the minimum of equipment and resources needed to produce low adhesion using a method more representative on Autumn conditions on rail and monitor the performance of rail vehicles when braking on it. This was mainly targeted at use for testing products applied to the wheel/rail interface to enhance traction, hence the need for real low adhesion causes. We present the methodology that we have developed, and some initial results showing that using it we can generate a low adhesion scenario when braking from 10 mph. This can be used to develop mitigation solutions for low adhesion in a more cost effective manner

Individual variability in preference for energy-dense foods fails to predict child BMI percentile

Many studies show that higher dietary energy density is associated with greater body weight. Here we explored two propositions: i) that child BMI percentile is associated with individual differences in children's relative preference for energy-dense foods, ii) that child BMI percentile is associated with the same individual differences between their parents. Child-parent dyads were recruited from a local interactive science center in Bristol (UK). Using computerized tasks, participants ranked their preference and rated their liking for a range of snack foods that varied in energy density. Children (aged 3–14 years, N = 110) and parents completed the tasks for themselves. Parents also completed two further tasks in which they ranked the foods in the order that they would prioritize for their child, and again, in the order that they thought their child would choose. Children preferred (t(109) = 3.91, p ≺ 0.001) and better liked the taste of (t(109) = 3.28, p = 0.001) higher energy-dense foods, and parents correctly estimated this outcome (t(109) = 7.18, p ≺ 0.001). Conversely, lower energy-dense foods were preferred (t(109) = − 4.63, p ≺ 0.001), better liked (t(109) = − 2.75, p = 0.007) and served (t(109) = − 15.06, p ≺ 0.001) by parents. However, we found no evidence that child BMI percentile was associated with child or parent preference for, or liking of, energy-dense foods. Therefore, we suggest that the observed relationship between dietary energy density and body weight is not explained by individual differences in preference for energy density

Parental beliefs about portion size, not children's own beliefs, predict child BMI

Background Increases in portion size are thought by many to promote obesity in children. However, this relationship remains unclear. Here, we explore the extent to which a child's BMI is predicted both by parental beliefs about their child's ideal and maximum portion size and/or by the child's own beliefs. Methods Parent–child (5–11 years) dyads (N = 217) were recruited from a randomized controlled trial (n = 69) and an interactive science centre (n = 148). For a range of main meals, parents estimated their child's ‘ideal’ and ‘maximum tolerated’ portions. Children completed the same tasks. Results An association was found between parents' beliefs about their child's ideal (β = .34, p < .001) and maximum tolerated (β = .30, p < .001) portions, and their child's BMI. By contrast, children's self‐reported ideal (β = .02, p = .718) and maximum tolerated (β = −.09, p = .214) portions did not predict their BMI. With increasing child BMI, parents' estimations aligned more closely with their child's own selected portions. Conclusions Our findings suggest that when a parent selects a smaller portion for their child than their child self‐selects, then the child is less likely to be obese. Therefore, public health measures to prevent obesity might include instructions to parents on appropriate portions for young children

Drainage representation in flood models: Application and analysis of capacity assessment framework

Drainage systems are an integral part of urban infrastructure to help transport and treat wastewater as well as manage flooding during extreme rainfall events. Although there is a significant cost associated with the creation, operation and maintenance of drainage systems, the representation of these systems in flood models is overly simplified. This simplification is due to data protection regulations, and the complexities associated with drainage network modelling. A new framework developed by Water UK in collaboration with the Environmental Agency and sewerage undertakers for UK Drainage Water Management Plans provides data on the capacity and performance of the drainage system. The output from this framework provides a new method of incorporating a more explicit representation of spatially varied drainage capacity in flood models. This study presents the first application of the UK’s capacity assessment framework (CAF) for drainage representation in flood models. We develop a method of using the CAF outputs to represent spatially varied drainage losses across a catchment and assess its impact on flood risk. Three catchments in Leeds are used to quantify the difference generated in flooding when using a national average removal rate (NARR, e.g., 12 mm/hr) and our CAF-derived rainfall removal rates. Although there is variance across catchments, the results show the CAF removal rates increase flood depths, velocities, and flood hazards when compared to the national average due to a more realistic representation of the real system drainage capacity. With the pressures of climate change and continued urban development, a better representation of real drainage systems capacities will become more important and will make local solutions more resilient and relevant to the realities on the ground

Keeping Pace with Your Eating: Visual Feedback Affects Eating Rate in Humans

Abstract Deliberately eating at a slower pace promotes satiation and eating quickly has been associated with a higher body mass index. Therefore, understanding factors that affect eating rate should be given high priority. Eating rate is affected by the physical/textural properties of a food, by motivational state, and by portion size and palatability. This study explored the prospect that eating rate is also influenced by a hitherto unexplored cognitive process that uses ongoing perceptual estimates of the volume of food remaining in a container to adjust intake during a meal. A 2 (amount seen; 300ml or 500ml) x 2 (amount eaten; 300ml or 500ml) between-subjects design was employed (10 participants in each condition). In two &apos;congruent&apos; conditions, the same amount was seen at the outset and then subsequently consumed (300ml or 500ml). To dissociate visual feedback of portion size and actual amount consumed, food was covertly added or removed from a bowl using a peristaltic pump. This created two additional &apos;incongruent&apos; conditions, in which 300ml was seen but 500ml was eaten or vice versa. We repeated these conditions using a savoury soup and a sweet dessert. Eating rate (ml per second) was assessed during lunch. After lunch we assessed fullness over a 60-minute period. In the congruent conditions, eating rate was unaffected by the actual volume of food that was consumed (300ml or 500ml). By contrast, we observed a marked difference across the incongruent conditions. Specifically, participants who saw 300ml but actually consumed 500ml ate at a faster rate than participants who saw 500ml but actually consumed 300ml. Participants were unaware that their portion size had been manipulated. Nevertheless, when it disappeared faster or slower than anticipated they adjusted their rate of eating accordingly. This suggests that the control of eating rate involves visual feedback and is not a simple reflexive response to orosensory stimulation

Episodic Memory and Appetite Regulation in Humans

Psychological and neurobiological evidence implicates hippocampal-dependent memory processes in the control of hunger and food intake. In humans, these have been revealed in the hyperphagia that is associated with amnesia. However, it remains unclear whether 'memory for recent eating' plays a significant role in neurologically intact humans. In this study we isolated the extent to which memory for a recently consumed meal influences hunger and fullness over a three-hour period. Before lunch, half of our volunteers were shown 300 ml of soup and half were shown 500 ml. Orthogonal to this, half consumed 300 ml and half consumed 500 ml. This process yielded four separate groups (25 volunteers in each). Independent manipulation of the 'actual' and 'perceived' soup portion was achieved using a computer-controlled peristaltic pump. This was designed to either refill or draw soup from a soup bowl in a covert manner. Immediately after lunch, self-reported hunger was influenced by the actual and not the perceived amount of soup consumed. However, two and three hours after meal termination this pattern was reversed - hunger was predicted by the perceived amount and not the actual amount. Participants who thought they had consumed the larger 500-ml portion reported significantly less hunger. This was also associated with an increase in the 'expected satiation' of the soup 24-hours later. For the first time, this manipulation exposes the independent and important contribution of memory processes to satiety. Opportunities exist to capitalise on this finding to reduce energy intake in humans

Keeping Pace with Your Eating: Visual Feedback Affects Eating Rate in Humans

Deliberately eating at a slower pace promotes satiation and eating quickly has been associated with a higher body mass index. Therefore, understanding factors that affect eating rate should be given high priority. Eating rate is affected by the physical/textural properties of a food, by motivational state, and by portion size and palatability. This study explored the prospect that eating rate is also influenced by a hitherto unexplored cognitive process that uses ongoing perceptual estimates of the volume of food remaining in a container to adjust intake during a meal. A 2 (amount seen; 300ml or 500ml) x 2 (amount eaten; 300ml or 500ml) between-subjects design was employed (10 participants in each condition). In two ‘congruent’ conditions, the same amount was seen at the outset and then subsequently consumed (300ml or 500ml). To dissociate visual feedback of portion size and actual amount consumed, food was covertly added or removed from a bowl using a peristaltic pump. This created two additional ‘incongruent’ conditions, in which 300ml was seen but 500ml was eaten or vice versa. We repeated these conditions using a savoury soup and a sweet dessert. Eating rate (ml per second) was assessed during lunch. After lunch we assessed fullness over a 60-minute period. In the congruent conditions, eating rate was unaffected by the actual volume of food that was consumed (300ml or 500ml). By contrast, we observed a marked difference across the incongruent conditions. Specifically, participants who saw 300ml but actually consumed 500ml ate at a faster rate than participants who saw 500ml but actually consumed 300ml. Participants were unaware that their portion size had been manipulated. Nevertheless, when it disappeared faster or slower than anticipated they adjusted their rate of eating accordingly. This suggests that the control of eating rate involves visual feedback and is not a simple reflexive response to orosensory stimulatio

Preferred Analyses and Sample Preparation for Surface Geochemical Sediment Samples in Petroleum Exploration*

A range of options is available for shallow core sample acquisition, preservation and analyses. In acquisition, it has been shown that gravity coring provides samples of equal quality to piston coring, at greater safety and lower cost; while the best preservation is freezing to-80°C, since bactericides do not always penetrate clay samples and will contaminate at least the solvent extracts. The advantages of analysing occluded and adsorbed gases instead of just headspace gas have also been shown. Regarding analyses of liquid hydrocarbons, the two most critical choices involve i) the bulk assessment of the total extract, and ii) the GC-MS analyses of the extract, and these techniques are the focus of this work. Bulk analysis of the extract usually involves performing both gas chromatography (GC) and total scanning fluorescence (TSF). The GC method shows in chromatogram form, directly and unequivocally, the compounds present in the sample and show if biodegradation has occurred. This analysis is indisputably necessary to perform, not only due to its ability to show at a glance the type of hydrocarbons present, but also, when the extraction is performed quantitatively, to give the amounts of thermogenic hydrocarbons as opposed to those from recent organic matter. TSF is rather an &apos;indirect&apos; method, targeting the aromatic compounds, and relying on the fluorescing properties of these under different wavelengths. By comparison with reference samples containing known types of hydrocarbons the emission data are qualitatively interpreted. It is shown here, however, that the TSF results do not consistently agree with the GC analyses, which are considered as the benchmark. The disagreement locally can be quite marked; e.g., TSF indicating thermogenic hydrocarbons in barren samples and vice versa. The value of performing TSF is then strongly questioned, especially as GC must in any case be performed on all samples

Intérêt de l'utilisation du dosage postopératoire de la troponine ultra-sensible après chirurgie orthopédique majeure

L'ischémie myocardique postopératoire (IMPO) est définie par une ascension isolée de troponine postopératoire. Cette complication cardiaque s'avère fréquente et grevée d'un mauvais pronostic à court, moyen et long terme après chirurgie non cardiaque. L'objectif de cette étude était d'évaluer la valeur pronostique de la troponine Ic ultra-sensible (TnIus) en terme de mortalité à 1 an postopératoire, après chirurgie orthopédique majeure. Un dosage quotidien de TnIus a été réalisé pendant les 3 premiers jours postopératoires chez 889 patients opérés d'arthroplastie hanche/genou, reprise d'arthroplastie, ou de fracture de hanche. Les valeurs de TnIus supérieures au 99ème percentile d'une population normale étaient considérées comme positives, et les valeurs inférieures au 99ème percentile étaient considérées comme détectables mais non significatives. Un suivi de la mortalité à 1 an postopératoire a ensuite été réalisé. L'incidence des IMPO était de 15%. L'incidence de la TnIus détectable était de 34%, et la mortalité de 3,2%. En analyse multivariée, les variables statistiquement associées avec la mortalité étaient le type de chirurgie, le caractère urgent de la chirurgie (HR 14,24;IC 95%,5,57 36,45), les IMPO (HR 3,83;IC 95%,1,28 11,42), l'absence de traitement par b-bloquants (HR7,79;IC 95%,1,75 34,6), et la présence d'une insuffisance rénale chronique. Après chirurgie orthopédique majeure, les IMPO sont associées à la mortalité postopératoire à long terme. Ce risque ne semble pas être stratifié en fonction du seuil de TnIus pris en compte. Un traitement par b-bloquants aurait un effet protecteur.PARIS6-Bibl.Pitié-Salpêtrie (751132101) / SudocPARIS-Bib. Serv.Santé Armées (751055204) / SudocSudocFranceF