Effets viscoélastiques dans les mesures des pressions statiques et d'arrêt

Total and static pressure measurements in visco-elastic fluids are subject to considerable interference. Measured dynamic pressures differ by up to 70 per cent from similar data for Newtonian fluids, due to such factors as flow velocity V0 outside probe diameter D0, viscosity μ, specific gravity Q and shear modulus of elasticity for the fluid G. It is found that there are two characteristic non-dimensional factors for the problem, one being the Reynolds number referred to D0 and the other the Deborah number relating characteristic flow to flow time. Tests have been carried out to establish the effect of the characteristic parameters, using a probe mounted on a rotating arm and moving at an exactly known rate in a circular tank and transmitting the pressure data to an external receiver. The tests were carried out in a solution of polyethylene and water over a range of concentrations. The pressure difference Dp was found to vary as the reciprocal of D, and it was seen that, depending on probe tip geometry, it either passed through a maximum or reached a step as V0 increased. The static pressure measurements were carried out in with the same equipment and the same fluids. Circular cylinders of varying outside diameter and with varying pressure tapping orifice angular position θ on a generatrix were tested at Reynolds numbers ranging from 1.52 X 101 to 6.0 X 101. The results differed from Newtonian fluid data, for which mainly D0, V0 and θ are significant. From the analysis of the results it was suspected that the difference might be due to the elastic fluid properties. The main differences were lower measured pressures in the neighbourhood of the stagnation point and a downstream shift of the separation point. The measured pressures in the intermediate zone and in the wake of the measured pressures were very close to those associated with the flow of a Newtonian fluid around a similar cylinder with delayed separation

The changing role of the senses in food choice and food intake across the lifespan

International audienceSensory perception begins before birth and enables us to interpret the biological relevance of stimuli in our near environment. In early life, the senses play a crucial role in informing acceptance and rejection of foods and beverages. Food preferences develop with experience based on associations formed between a foods flavour and the consequence of its consumption. In adulthood the role of the chemical senses is often simplified into simple 'likes' and 'dislikes', but recent evidence highlights a more functional role in guiding eating behaviours and nutrition. A food’s perceptual properties are important for the detection of its nutrient content and through this, guide not only food choice but also habitual energy selection and consumption behaviour. As we age and the prevalence of chronic disease increases, sensory acuity often declines for taste, smell and texture perception, and this can have an impact on food perception, preference and food intake. This creates an opportunity to apply an understanding of sensory influences on choice and intake to stimulate appetite during periods where nutrient intakes may become compromised. This paper summarises current knowledge of the changing role of the senses during infancy and early childhood, through to adulthood, older age and illness. The aim is to highlight opportunities to improve health and wellness through a better understanding of how sensory factors can influence eating behaviours and nutrition at key time points across the lifespan

Effet de l’âge sur les consommations alimentaires et les raisons de non-consommation : résultats d’une enquête menée auprès de 32 000 adultes âgés de 20 à 80 ans

International audienc

Oral health and adherence to national dietary guidelines in France

International audienc

Acromicric dysplasia: long term outcome and evidence of autosomal dominant inheritance

Acromicric dysplasia is a rare bone dysplasia characterised by short stature, short hands and feet, normal intelligence, mild facial dysmorphism, and characteristic x ray abnormalities of the hands. Only a very small number of children with this condition have been reported so far. Here we report on a series of 22 patients including 10 boys and 12 girls with acromicric dysplasia. Length was normal at birth and height fell progressively off the centiles postnatally. The mean adult height was 130 cm (133 cm in males, 129 cm in females). The hands, feet, and limbs were short and OFC was normal. Intelligence was normal and mild dysmorphic features were noted. Other occasional features included well developed muscles, a hoarse voice, generalised joint limitation in some patients, frequent ear, tracheal, and respiratory complication, and spine abnormalities. Long term follow up showed that facial dysmorphism was less obvious in adults and that carpal tunnel syndrome was frequent in older patients. Apart from short metacarpals and phalanges, internal notch of the second metacarpal, external notch of the fifth metacarpal, and internal notch of the femoral heads, there were no major x ray abnormalities. No major complications, such as cardiac disease or major orthopaedic problems, occurred in the course of the disease. The condition appeared to be sporadic in 16 cases but the observation of vertical transmission in three families was consistent with an autosomal dominant mode of inheritance.


Keywords: acromicric dysplasia; geleophysic dysplasia; long term outcome; autosomal dominant inheritanc