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ABSTRACTThis article reviews a computer‐based method to predict transit time parameters (mean and variance) from historical data for use in logistics planning analysis. Efficient use of the data depends on relating it to a grid system of the United States. Performance of the technique on a sample of shipments by four methods of transportation is compared to a system based solely on highway distance. The techniques perform equally well for average transit time (speed). The grid system method demonstrates superior predicting power for reliability (transit time variance). Use of the system in daily operations is also anticipated.

International audience ; To understand mobility in the future, we must not look just at changes in transportation, which simply serve as variables in the general equation. Over the past decades, the factor of speed has made mobility democratic owing to relatively lower prices. This trend has met its limits. The "commercial" speeds of various forms of transport are stable or even declining. To imagine mobility in the future, focus must be shifted from speed to the new ways (individual and collective) of managing time, which has become the scarcest resource for people. For this reason, public policy has set as priority "daily forms of mobility", which are subjected to financial, energy and environmental conditions. The aim is no longer to increase speed but to optimize the management of space, the scarcest collective resource. ; Pour comprendre les mobilités du futur, il ne faut pas regarder seulement du côté de l'évolution des moyens de transport. Ils ne sont qu'une des variables de l'équation des mobilités. Au cours des dernières décennies, l'accès à la vitesse s'est démocratisé du fait de la baisse de son prix relatif. Ce mouvement rencontre pourtant des limites. Les vitesses commerciales des différents modes de transport sont stables, voire régressent. Pour concevoir le futur de la mobilité, nous devons non pas nous polariser sur la vitesse, mais sur les formes nouvelles, individuelles et col­lectives de la gestion du temps, ce dernier étant devenu pour les individus la ressource la plus rare. C'est la raison pour laquelle les politiques publiques donnent aujourd'hui la priorité aux mobilités quotidiennes en les soumettant à des contraintes financières, énergétiques et environ­nementales. Pour cela, elles ne visent plus à accroître les vitesses, mais à optimiser la gestion de la ressource collective la plus rare : l'espace.

International audience ; To understand mobility in the future, we must not look just at changes in transportation, which simply serve as variables in the general equation. Over the past decades, the factor of speed has made mobility democratic owing to relatively lower prices. This trend has met its limits. The "commercial" speeds of various forms of transport are stable or even declining. To imagine mobility in the future, focus must be shifted from speed to the new ways (individual and collective) of managing time, which has become the scarcest resource for people. For this reason, public policy has set as priority "daily forms of mobility", which are subjected to financial, energy and environmental conditions. The aim is no longer to increase speed but to optimize the management of space, the scarcest collective resource. ; Pour comprendre les mobilités du futur, il ne faut pas regarder seulement du côté de l'évolution des moyens de transport. Ils ne sont qu'une des variables de l'équation des mobilités. Au cours des dernières décennies, l'accès à la vitesse s'est démocratisé du fait de la baisse de son prix relatif. Ce mouvement rencontre pourtant des limites. Les vitesses commerciales des différents modes de transport sont stables, voire régressent. Pour concevoir le futur de la mobilité, nous devons non pas nous polariser sur la vitesse, mais sur les formes nouvelles, individuelles et col­lectives de la gestion du temps, ce dernier étant devenu pour les individus la ressource la plus rare. C'est la raison pour laquelle les politiques publiques donnent aujourd'hui la priorité aux mobilités quotidiennes en les soumettant à des contraintes financières, énergétiques et environ­nementales. Pour cela, elles ne visent plus à accroître les vitesses, mais à optimiser la gestion de la ressource collective la plus rare : l'espace.

International audience ; To understand mobility in the future, we must not look just at changes in transportation, which simply serve as variables in the general equation. Over the past decades, the factor of speed has made mobility democratic owing to relatively lower prices. This trend has met its limits. The "commercial" speeds of various forms of transport are stable or even declining. To imagine mobility in the future, focus must be shifted from speed to the new ways (individual and collective) of managing time, which has become the scarcest resource for people. For this reason, public policy has set as priority "daily forms of mobility", which are subjected to financial, energy and environmental conditions. The aim is no longer to increase speed but to optimize the management of space, the scarcest collective resource. ; Pour comprendre les mobilités du futur, il ne faut pas regarder seulement du côté de l'évolution des moyens de transport. Ils ne sont qu'une des variables de l'équation des mobilités. Au cours des dernières décennies, l'accès à la vitesse s'est démocratisé du fait de la baisse de son prix relatif. Ce mouvement rencontre pourtant des limites. Les vitesses commerciales des différents modes de transport sont stables, voire régressent. Pour concevoir le futur de la mobilité, nous devons non pas nous polariser sur la vitesse, mais sur les formes nouvelles, individuelles et col­lectives de la gestion du temps, ce dernier étant devenu pour les individus la ressource la plus rare. C'est la raison pour laquelle les politiques publiques donnent aujourd'hui la priorité aux mobilités quotidiennes en les soumettant à des contraintes financières, énergétiques et environ­nementales. Pour cela, elles ne visent plus à accroître les vitesses, mais à optimiser la gestion de la ressource collective la plus rare : l'espace.

Background Non-invasive continuous blood pressure monitors are of great interest to the medical community due to their value in hypertension management. Recently, studies have shown the potential of pulse pressure as a therapeutic target for hypertension, but not enough attention has been given to non-invasive continuous monitoring of pulse pressure. Although accurate pulse pressure estimation can be of direct value to hypertension management and indirectly to the estimation of systolic blood pressure, as it is the sum of pulse pressure and diastolic blood pressure, only a few inadequate methods of pulse pressure estimation have been proposed. Methods We present a novel, non-invasive blood pressure and pulse pressure estimation method based on pulse transit time and pre-ejection period. Pre-ejection period and pulse transit time were measured non-invasively using electrocardiogram, seismocardiogram, and photoplethysmogram measured from the torso. The proposed method used the 2-element Windkessel model to model pulse pressure with the ratio of stroke volume, approximated by pre-ejection period, and arterial compliance, estimated by pulse transit time. Diastolic blood pressure was estimated using pulse transit time, and systolic blood pressure was estimated as the sum of the two estimates. The estimation method was verified in 11 subjects in two separate conditions with induced cardiovascular response and the results were compared against a reference measurement and values obtained from a previously proposed method. Results The proposed method yielded high agreement with the reference (pulse pressure correlation with reference R ≥ 0.927, diastolic blood pressure correlation with reference R ≥ 0.854, systolic blood pressure correlation with reference R ≥ 0.914) and high estimation accuracy in pulse pressure (mean root-mean-squared error ≤ 3.46 mmHg) and blood pressure (mean root-mean-squared error ≤ 6.31 mmHg for diastolic blood pressure and ≤ 8.41 mmHg for systolic blood pressure) over a wide range of hemodynamic changes. Conclusion The proposed pulse pressure estimation method provides accurate estimates in situations with and without significant changes in stroke volume. The proposed method improves upon the currently available systolic blood pressure estimation methods by providing accurate pulse pressure estimates. ; This study was supported by the Bio & Medical Technology Development Program of the National Research Foundation (NRF), funded by the Korean government (MSIP & MOHW) (No. 2016M3A9F1939646).

Jean-François Brugère thanks bachelors'students for their help, more specifically Céline Vidal, Claire Ardaens,Adeline Régnier, and Amandine Maurin, and Sylvain Denis forhis valuable help concerning in vitro systems. In memory of GeorgeT MacFarlane (died in 2015) for all of his pioneering works on gut in vitro simulations systemsThis work was supported by the European Union (UE) through the Auvergne Council (FEDER) with a PhD and a postdoctoral Scholarship support respectively to William Tottey and to David Feria-Gervasio, and by a PhD scholarship support from the French "Ministere de l'Enseignement Superieur et de la Recherche" to Nadia Gaci ; Background/Aims: Human gut microbiota harbors numerous metabolic properties essential for the host's health. Increased intestinal transit time affects a part of the population and is notably observed with human aging, which also corresponds to modifications of the gut microbiota. Thus we tested the metabolic and compositional changes of a human gut microbiota induced by an increased transit time simulated in vitro. Methods: The in vitro system, Environmental Control System for Intestinal Microbiota, was used to simulate the environmental conditions of 3 different anatomical parts of the human colon in a continuous process. The retention times of the chemostat conditions were established to correspond to a typical transit time of 48 hours next increased to 96 hours. The bacterial communities, short chain fatty acids and metabolite fingerprints were determined. Results: Increase of transit time resulted in a decrease of biomass and of diversity in the more distal compartments. Short chain fatty acid analyses and metabolite fingerprinting revealed increased activity corresponding to carbohydrate fermentation in the proximal compartments while protein fermentations were increased in the lower parts. Conclusions: This study provides the evidence that the increase of transit time, independently of other factors, affects the composition and metabolism of the gut microbiota. The transit time is one of the factors that explain some of the modifications seen in the gut microbiota of the elderly, as well as patients with slow transit time.

Jean-François Brugère thanks bachelors'students for their help, more specifically Céline Vidal, Claire Ardaens,Adeline Régnier, and Amandine Maurin, and Sylvain Denis forhis valuable help concerning in vitro systems. In memory of GeorgeT MacFarlane (died in 2015) for all of his pioneering works on gut in vitro simulations systemsThis work was supported by the European Union (UE) through the Auvergne Council (FEDER) with a PhD and a postdoctoral Scholarship support respectively to William Tottey and to David Feria-Gervasio, and by a PhD scholarship support from the French "Ministere de l'Enseignement Superieur et de la Recherche" to Nadia Gaci ; Background/Aims: Human gut microbiota harbors numerous metabolic properties essential for the host's health. Increased intestinal transit time affects a part of the population and is notably observed with human aging, which also corresponds to modifications of the gut microbiota. Thus we tested the metabolic and compositional changes of a human gut microbiota induced by an increased transit time simulated in vitro. Methods: The in vitro system, Environmental Control System for Intestinal Microbiota, was used to simulate the environmental conditions of 3 different anatomical parts of the human colon in a continuous process. The retention times of the chemostat conditions were established to correspond to a typical transit time of 48 hours next increased to 96 hours. The bacterial communities, short chain fatty acids and metabolite fingerprints were determined. Results: Increase of transit time resulted in a decrease of biomass and of diversity in the more distal compartments. Short chain fatty acid analyses and metabolite fingerprinting revealed increased activity corresponding to carbohydrate fermentation in the proximal compartments while protein fermentations were increased in the lower parts. Conclusions: This study provides the evidence that the increase of transit time, independently of other factors, affects the composition and metabolism of the gut microbiota. The ...