1,452 research outputs found
Generation of silicone poly-HIPES with controlled pore sizes via reactive emulsion stabilization
Macrocellular silicone polymers are obtained after solidification of the
continuous phase of a PDMS (polydimethylsiloxane) emulsion, which contains PEG
(polyethylene glycol) drops of sub-millimetric dimensions. Coalescence of the
liquid template emulsion is prohibited by a reactive blending approach. We
investigate in detail the relationship between the interfacial properties and
the emulsion stability, and we use micro- and millifluidic techniques to
generation macro-cellular polymers with controlled structural properties over a
wider range of cell-sizes (0.2-2mm) and volume fractions of the continuous
phase (0.1-40%). This approach could easily be transferred to a wide range of
polymeric systems
Pulse pressure and cardiovascular autonomic neuropathy according to duration of type 1 diabetes.
peer reviewedBACKGROUND: To evaluate changes in pulse pressure (PP) and markers of cardiovascular autonomic neuropathy (CAN) according to duration of type 1 diabetes mellitus (T1DM). METHODS: This cross-sectional controlled study evaluated 159 diabetic patients during a 3-min posture test (standing-squatting-standing) with continuous measurement of systolic (SBP), diastolic (DBP) and mean (MBP) blood pressure by a Finapres device. Arterial stiffness was indirectly assessed by PP and the slope of PP as a function of MBP calculated during the whole 3-min test. CAN was assessed by the expiration/inspiration pulse interval ratio (E/I R-R ratio) during deep breathing and by three indices measured during the squatting test. Patients were divided into four groups according to diabetes duration ( 30 years from group 1 to group 4, respectively) and compared with age-matched non-diabetic subjects. RESULTS: PP progressively increased (p < 0.0001) and PP/MBP decreased (p < 0.0005) according to T1DM duration, whereas these parameters remained almost unchanged in age-matched control subjects. E/I ratio (p < 0.0001) and baroreflex gain (p < 0.0005) progressively decreased with T1DM duration. The parasympathetic index (squatting test vagal ratio-SqTv) significantly increased (p < 0.0001), whereas the sympathetic index (squatting test sympathetic ratio-SqTs) only tended to decrease (p = 0.12) according to diabetes duration. No such changes in CAN indices were observed in the non-diabetic population. CONCLUSIONS: PP increased according to T1DM duration in an age range where PP remained almost stable in controls, in agreement with accelerated arterial stiffening due to chronic hyperglycaemia. The baroreflex gain decreased and other indices of CAN also deteriorated with diabetes duration, more so indices reflecting parasympathetic rather than sympathetic dysfunction
Active rough shape estimation of unknown objects
International audienceThis paper presents a method to determine the rough shape of an object. This is a step in the development of a One Click Grasping Tool, a grasping tool of everyday-life objects for an assistant robot dedicated to elderly or disabled. The goal is to determine the quadric that approximates at best the shape of an unknown object using multi-view measurements. Non-linear optimization techniques are considered to achieve this goal. Since multiple views are necessary, an active vision process is considered in order to minimize the uncertainty on the estimated parameters and determine the next best view. Finally, results that show the validity of the approach are presented
Event-based control of linear hyperbolic systems of conservation laws
International audienceIn this article, we introduce event-based boundary controls for 1-dimensional linear hyperbolic systems of conservation laws. Inspired by event-triggered controls developed for finite-dimensional systems, an extension to the infinite dimensional case by means of Lyapunov techniques, is studied. The main contribution of the paper lies in the definition of two event-triggering conditions, by which global exponential stability and well-posedness of the system under investigation is achieved. Some numerical simulations are performed for the control of a system describing traffic flow on a roundabout
Effets de la durée du diabète de type 1 sur la pression artérielle pulsée : résultats d’une étude transversale comparative à un groupe contrôle non diabétique.
peer reviewe
Arterial pulse pressure in relation to the duration of type 1 diabetes: a cross-sectional controlled study
Diabetes mellitus and arterial pulse pressure (PP) are two independent cardiovascular risk factors. This cross-sectional study investigated the influence of diabetes duration on PP in type 1 diabetic patients without any cardiovascular disease. PP was measured continuously during 3 minutes (active orthostatic test: 1 min standing--1 min squatting--1 min standing) using a fingertip plethysmograph (Finapres) in 159 type 1 diabetic patients aged 20-60 yrs. They were divided into 4 groups according to diabetes duration: (1) G1 : 30 yrs (n=18). In order to separate the effects of age from the effects of diabetes duration, diabetic patients were compared to age- and sex-matched non diabetic controls. PP (expressed in mmHg; mean +/- SD) was higher in men than in women in both diabetic (58 +/- 15 vs. 50 +/- 14; p = 0.001) and non diabetic subjects (55 +/- 14 vs. 47 +/- 12; p = 0.001). Overall PP was higher in diabetic than in non diabetic individuals (54 +/- 15 vs. 50 +/- 13; p = 0.025). PP progressively increased according to diabetes duration: 47 +/- 16 vs. 51 +/- 13 vs. 59 +/- 14 vs. 62 +/- 12, from G1 to G4 respectively; p or =8% (55 +/- 16), with (57 +/- 17) or without (54 +/- 14) microalbuminuria, treated (56 +/- 14) or not (54 +/- 15) by inhibitors of the renin-angiotensin system. In conclusion, PP progressively increased with the duration of type 1 diabetes, independently of age. Such increase was more marked in squatting than in standing position. The role of such PP rise in the increased cardiovascular risk of patients with type 1 diabetes, although suspected in the recent EURODIAB Prospective Complications Study, deserves further investigation
Microgynous Queens in the Paleartic Ant, Manica rubida: Dispersal Morphs or Social Parasites?
In many ant species, queen size is dimorphic, with small microgynes and large macrogynes, which differ, for example, in size, insemination rate, ovary development, and dispersal tactics. These polymorphic queens often correspond with alternative reproductive strategies. The Palearctic ant, Manica rubida (Latreille) (Hymenoptera: Formicidae), lives mostly in mountainous regions in either monogynous colonies, containing one macrogynous queen or polygynous colonies, containing a few large macrogynous queens. In 1998, a colony of M. rubida was discovered containing macrogynes and many small alate microgynes that did not engage in a nuptial flight but, instead, stayed in the home nest the following winter. These microgynes were studied more closely by investigating their size, behavior, and spermatheca in relation to M. rubida macrogynes and workers. Mitochondrial DNA of macrogynes, microgynes and workers from four nests was sequenced to detect possible genetic differences between them. The microgynes were significantly smaller than the macrogynes, and the head width of the gynes was completely bimodal. The microgynes behaved like workers of the macrogynes in every experiment tested. Furthermore, the microgynes had a normal spermatheca and could be fecundated, but rarely (only one in several years). Finally, all the individuals were genetically identical, except three workers that differed by only one codon position. Because these microgynes have features of both queens and workers, their functional significance in the colony is not yet clear
Exhaust gas sensor based on tin dioxide for automotive application
International audienceThe aim of this paper is to investigate the potentialities of gas sensor based on semi-conductor for exhaust gas automotive application. The sensing element is a tin dioxide layer with gold electrodes. This gas sensor is able to detect both reducing and oxidizing gases in an exhaust pipe with varying selectivity depending on the temperature in the range 250° C-600° C. At low temperature 350-400° C, the sensor detects nitrogen dioxide while it is more sensitive to carbon monoxide at temperatures exceeding 500° C
Nouvelles recherches sur l'ensemble paléochrétien et médiéval d'Ereruyk en Arménie
Premiers résultats des campagnes d'investigations menées en 2009-2011 sur le site paléochrétien et médiéval d'Ereruyk, dans le nord-ouest de la république d'Arménie, par une équipe du LA3M (UMR 7298, Aix-Marseille Université / CNRS)
Ermant (2022)
Données scientifiques produites :Dépôt sharedocs.huma-num.fr https://www.asm.cnrs.fr/les-fouilles/ermant http://www.montpellier-egyptologie.fr/ermanthttps://www.ifao.egnet.net/archeologie/ermant/ 1. Le temple ptolémaïque et romain de Montou-Rê Christophe Thiers Fig. 1. Localisation des secteurs étudiés (D. Laisney, Y. Mohamed, P. Zignani 2008). © CNRS-Ifao. 17149_2022_NDMCN_001 1.1. Relevés épigraphiques Très peu de blocs ont été mis au jour cette saison. On signalera un bloc (914) ayant pro..
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