19 research outputs found
Author response image 5.
No full textInternational audienceCollective migration is a complex process that contributes to build precise tissue and organ architecture. Several molecules implicated in cell interactions also control collective migration, but their precise role and the finely tuned expression that orchestrates this complex developmental process are poorly understood. Here, we show that the timely and threshold expression of the Netrin receptor Frazzled triggers the initiation of glia migration in the developing Drosophila wing. Frazzled expression is induced by the transcription factor Glide/Gcm in a dose-dependent manner. Thus, the glial determinant also regulates the efficiency of collective migration. NetrinB but not NetrinA serves as a chemoattractant and Unc5 contributes as a repellant Netrin receptor for glia migration. Our model includes strict spatial localization of a ligand, a cell autonomously acting receptor and a fate determinant that act coordinately to direct glia toward their final destination
Classification of red wines analysed by middle infrared spectroscopy of dry extract according to their geographical origin
No full textMid-infrared transmission spectroscopy and classical analyses have been used to classify 165 wines of the same variety (Gamay), from three geographical origins (Gaillac, Beaujolais and Touraine). For spectroscopic analyses; the wines were dried on polyethylene membrane and infrared spectra were recorded by transmission between 800 cm-1 and 1800 cm-1. Classical analyses included pH, total acidity, total phenol, colour, sugars and major acids. The three groups of wines were classified by applying factorial discriminant analyses with cross validation. 97 p. cent of wines were correctly classified, based on the infrared data, versus 67 p. cent based on the classical analyses
Mathematical model of in vitro digestion of infant formulas
No full textMenard O., Cattenoz T., Guillemin H., Souchon I., Deglaire A., Dupont D., Picque D. (2014). Validation of a new in vitro dynamic system to simulate infant digestion. Food Chemistry 145, 1039-1045.Menard O., Cattenoz T., Guillemin H., Souchon I., Deglaire A., Dupont D., Picque D. (2014). Validation of a new in vitro dynamic system to simulate infant digestion. Food Chemistry 145, 1039-1045.The prediction of the digestion kinetics of infant formulas depending on their lipid and protein composition would be of great interest (i) to limit time-consuming and costly in vitro or in vivo experiments, (ii) to optimize their digestibility and (iii) to predict the fate of newly developed formulas in the gastrointestinal tract.This study aimed to establish a mechanistic model of the kinetics of proteolysis and lipolysis during the gastric and intestinal digestion of two different infant formulas using an in vitro dynamic simulator with two-compartments: stomach and small intestine1. Experimental data were available from a previous study2.The model approach was based on mass and volume balance equations on the different proteins ( -lactalbulmin, -lactoglobulin and caseins), triacylglycerides (TAG) and digestive enzymes (pepsin, lipase and pancreatin), assuming the stomach and small intestine as two perfectly stirred reactors displayed in series and at steady state. For each infant formula, a system of 11 differential equations with 6 unknown parameters was implemented in Matlab® software for resolution. These unknown parameters, which correspond to the enzymatic reaction rates, were estimated by finding the minimum of constrained nonlinear multivariable function between the solutions of the mathematical model and experimental data with the fmincon function.The mathematical model will be extended to four other experimental data sets of in vitro digestions of infant formulas presenting various fat and protein compositions and different rheological properties, in order to test its ability to predict their kinetics of digestion. A proper modelling of dynamic in vitro digestion phenomena occurring in the gastrointestinal tract is a challenging task, but could be of great help to better understand the key factors involved in the final nutritional quality of infant milk constituants
Mathematical model of in vitro digestion of infant formulas
No full textMenard O., Cattenoz T., Guillemin H., Souchon I., Deglaire A., Dupont D., Picque D. (2014). Validation of a new in vitro dynamic system to simulate infant digestion. Food Chemistry 145, 1039-1045.Menard O., Cattenoz T., Guillemin H., Souchon I., Deglaire A., Dupont D., Picque D. (2014). Validation of a new in vitro dynamic system to simulate infant digestion. Food Chemistry 145, 1039-1045.The prediction of the digestion kinetics of infant formulas depending on their lipid and protein composition would be of great interest (i) to limit time-consuming and costly in vitro or in vivo experiments, (ii) to optimize their digestibility and (iii) to predict the fate of newly developed formulas in the gastrointestinal tract.This study aimed to establish a mechanistic model of the kinetics of proteolysis and lipolysis during the gastric and intestinal digestion of two different infant formulas using an in vitro dynamic simulator with two-compartments: stomach and small intestine1. Experimental data were available from a previous study2.The model approach was based on mass and volume balance equations on the different proteins ( -lactalbulmin, -lactoglobulin and caseins), triacylglycerides (TAG) and digestive enzymes (pepsin, lipase and pancreatin), assuming the stomach and small intestine as two perfectly stirred reactors displayed in series and at steady state. For each infant formula, a system of 11 differential equations with 6 unknown parameters was implemented in Matlab® software for resolution. These unknown parameters, which correspond to the enzymatic reaction rates, were estimated by finding the minimum of constrained nonlinear multivariable function between the solutions of the mathematical model and experimental data with the fmincon function.The mathematical model will be extended to four other experimental data sets of in vitro digestions of infant formulas presenting various fat and protein compositions and different rheological properties, in order to test its ability to predict their kinetics of digestion. A proper modelling of dynamic in vitro digestion phenomena occurring in the gastrointestinal tract is a challenging task, but could be of great help to better understand the key factors involved in the final nutritional quality of infant milk constituants
Mathematical model of in vitro digestion of infant formulas
No full textMenard O., Cattenoz T., Guillemin H., Souchon I., Deglaire A., Dupont D., Picque D. (2014). Validation of a new in vitro dynamic system to simulate infant digestion. Food Chemistry 145, 1039-1045.Menard O., Cattenoz T., Guillemin H., Souchon I., Deglaire A., Dupont D., Picque D. (2014). Validation of a new in vitro dynamic system to simulate infant digestion. Food Chemistry 145, 1039-1045.The prediction of the digestion kinetics of infant formulas depending on their lipid and protein composition would be of great interest (i) to limit time-consuming and costly in vitro or in vivo experiments, (ii) to optimize their digestibility and (iii) to predict the fate of newly developed formulas in the gastrointestinal tract.This study aimed to establish a mechanistic model of the kinetics of proteolysis and lipolysis during the gastric and intestinal digestion of two different infant formulas using an in vitro dynamic simulator with two-compartments: stomach and small intestine1. Experimental data were available from a previous study2.The model approach was based on mass and volume balance equations on the different proteins ( -lactalbulmin, -lactoglobulin and caseins), triacylglycerides (TAG) and digestive enzymes (pepsin, lipase and pancreatin), assuming the stomach and small intestine as two perfectly stirred reactors displayed in series and at steady state. For each infant formula, a system of 11 differential equations with 6 unknown parameters was implemented in Matlab® software for resolution. These unknown parameters, which correspond to the enzymatic reaction rates, were estimated by finding the minimum of constrained nonlinear multivariable function between the solutions of the mathematical model and experimental data with the fmincon function.The mathematical model will be extended to four other experimental data sets of in vitro digestions of infant formulas presenting various fat and protein compositions and different rheological properties, in order to test its ability to predict their kinetics of digestion. A proper modelling of dynamic in vitro digestion phenomena occurring in the gastrointestinal tract is a challenging task, but could be of great help to better understand the key factors involved in the final nutritional quality of infant milk constituants
Mathematical model of in vitro digestion of infant formulas
No full textMenard O., Cattenoz T., Guillemin H., Souchon I., Deglaire A., Dupont D., Picque D. (2014). Validation of a new in vitro dynamic system to simulate infant digestion. Food Chemistry 145, 1039-1045.The prediction of the digestion kinetics of infant formulas depending on their lipid and protein composition would be of great interest (i) to limit time-consuming and costly in vitro or in vivo experiments, (ii) to optimize their digestibility and (iii) to predict the fate of newly developed formulas in the gastrointestinal tract.This study aimed to establish a mechanistic model of the kinetics of proteolysis and lipolysis during the gastric and intestinal digestion of two different infant formulas using an in vitro dynamic simulator with two-compartments: stomach and small intestine1. Experimental data were available from a previous study2.The model approach was based on mass and volume balance equations on the different proteins ( -lactalbulmin, -lactoglobulin and caseins), triacylglycerides (TAG) and digestive enzymes (pepsin, lipase and pancreatin), assuming the stomach and small intestine as two perfectly stirred reactors displayed in series and at steady state. For each infant formula, a system of 11 differential equations with 6 unknown parameters was implemented in Matlab® software for resolution. These unknown parameters, which correspond to the enzymatic reaction rates, were estimated by finding the minimum of constrained nonlinear multivariable function between the solutions of the mathematical model and experimental data with the fmincon function.The mathematical model will be extended to four other experimental data sets of in vitro digestions of infant formulas presenting various fat and protein compositions and different rheological properties, in order to test its ability to predict their kinetics of digestion. A proper modelling of dynamic in vitro digestion phenomena occurring in the gastrointestinal tract is a challenging task, but could be of great help to better understand the key factors involved in the final nutritional quality of infant milk constituants
Mathematical model of in vitro digestion of infant formulas
No full textMenard O., Cattenoz T., Guillemin H., Souchon I., Deglaire A., Dupont D., Picque D. (2014). Validation of a new in vitro dynamic system to simulate infant digestion. Food Chemistry 145, 1039-1045.The prediction of the digestion kinetics of infant formulas depending on their lipid and protein composition would be of great interest (i) to limit time-consuming and costly in vitro or in vivo experiments, (ii) to optimize their digestibility and (iii) to predict the fate of newly developed formulas in the gastrointestinal tract.This study aimed to establish a mechanistic model of the kinetics of proteolysis and lipolysis during the gastric and intestinal digestion of two different infant formulas using an in vitro dynamic simulator with two-compartments: stomach and small intestine1. Experimental data were available from a previous study2.The model approach was based on mass and volume balance equations on the different proteins ( -lactalbulmin, -lactoglobulin and caseins), triacylglycerides (TAG) and digestive enzymes (pepsin, lipase and pancreatin), assuming the stomach and small intestine as two perfectly stirred reactors displayed in series and at steady state. For each infant formula, a system of 11 differential equations with 6 unknown parameters was implemented in Matlab® software for resolution. These unknown parameters, which correspond to the enzymatic reaction rates, were estimated by finding the minimum of constrained nonlinear multivariable function between the solutions of the mathematical model and experimental data with the fmincon function.The mathematical model will be extended to four other experimental data sets of in vitro digestions of infant formulas presenting various fat and protein compositions and different rheological properties, in order to test its ability to predict their kinetics of digestion. A proper modelling of dynamic in vitro digestion phenomena occurring in the gastrointestinal tract is a challenging task, but could be of great help to better understand the key factors involved in the final nutritional quality of infant milk constituants
Camembert-type cheese ripening dynamics are changed by the properties of wrapping films
No full textFour gas-permeable wrapping films exhibiting different degrees of water permeability (ranging from 1.6 to 500 g/m(2) per d) were tested to study their effect on soft-mold (Camembert-type) cheese-ripening dynamics compared with unwrapped cheeses. Twenty-three-day trials were performed in 2 laboratory-size (18 L) respiratory-ripening cells under controlled temperature (6 +/- 0.5 degrees C), relative humidity (75 +/- 2%), and carbon dioxide content (0.5 to 1%). The films allowed for a high degree of respiratory activity; no limitation in gas permeability was observed. The wide range of water permeability of the films led to considerable differences in cheese water loss (from 0.5 to 12% on d 23, compared with 15% for unwrapped cheeses), which appeared to be a key factor in controlling cheese-ripening progress. A new relationship between 2 important cheese-ripening descriptors (increase of the cheese core pH and increase of the cheese's creamy underrind thickness) was shown in relation to the water permeability of the wrapping film. High water losses (more than 10 to 12% on d 23) also were observed for unwrapped cheeses, leading to Camembert cheeses that were too dry and poorly ripened. On the other hand, low water losses (from 0.5 to 1% on d 23) led to over-ripening in the cheese underrind, which became runny as a result. Finally, water losses from around 3 to 6% on d 23 led to good ripening dynamics and the best cheese quality. This level of water loss appeared to be ideal in terms of cheese-wrapping film design
Beam induced heating
No full textIn 2011, the rapid increase of the luminosity performance of LHC came at the expense of increased temperature and pressure readings on several near-beam LHC equipments. In some cases, this beam induced heating was suspected to cause beam dumps and even degradation of the equipment. This contribution aims at gathering the observations of beam induced heating due to beam coupling impedance, their current level of understanding and possible actions that could be implemented during the winter stop 2011-2012
