Geometric Stability Analysis for Periodic Solutions of the Swift-Hohenberg Equation

In this paper we describe invariant geometrical ~structures in the phase space of the Swift-Hohenberg equation in a neighborhood of its periodic stationary states. We show that in spite of the fact that these states are only marginally stable (i.e., the linearized problem about these states has continuous spectrum extending all the way up to zero), there exist finite dimensional invariant manifolds in the phase space of this equation which determine the long-time behavior of solutions near these stationary solutions. In particular, using this point of view, we obtain a new demonstration of Schneider's recent proof that these states are nonlinearly stable.Comment: 44 pages, plain tex, 0 figure

Asymptotic description of solutions of the exterior Navier Stokes problem in a half space

We consider the problem of a body moving within an incompressible fluid at constant speed parallel to a wall, in an otherwise unbounded domain. This situation is modeled by the incompressible Navier-Stokes equations in an exterior domain in a half space, with appropriate boundary conditions on the wall, the body, and at infinity. We focus on the case where the size of the body is small. We prove in a very general setup that the solution of this problem is unique and we compute a sharp decay rate of the solution far from the moving body and the wall

Effect of substrate thermal resistance on space-domain microchannel

In recent years, Fluorescent Melting Curve Analysis (FMCA) has become an almost ubiquitous feature of commercial quantitative PCR (qPCR) thermal cyclers. Here a micro-fluidic device is presented capable of performing FMCA within a microchannel. The device consists of modular thermally conductive blocks which can sandwich a microfluidic substrate. Opposing ends of the blocks are held at differing temperatures and a linear thermal gradient is generated along the microfluidic channel. Fluorescent measurements taken from a sample as it passes along the micro-fluidic channel permits fluorescent melting curves to be generated. In this study we measure DNA melting temperature from two plasmid fragments. The effects of flow velocity and ramp-rate are investigated, and measured melting curves are compared to those acquired from a commercially available PCR thermocycler

Cross-site assessment of road design packages

This report develop a concept for evaluating alternative design solutions for urban streets: the Street Performance Assessment Scheme. It should be generally valid and applicable to any redesign task, to compare the performance of a road/street section: (1) with the goals formulated for each case study, (2) in situations before and after the implementation of a redesign solution, and (3) between different case studies in cross-site assessments. In this report, the Street Performance Assessment Scheme is applied to streets in five European cities. These streets have major movement and 'place' functions and have limited space availabilities, and are thus typical examples for the most challenging design tasks that urban street designers face

Built Environment Determinants of Pedestrian Activities and Their Consideration in Urban Street Design

Pedestrian facilities have been regarded in urban street design as “leftover spaces” for years, but, currently, there is a growing interest in walking and improving the quality of street environments. Designing pedestrian facilities presents the challenge of simultaneously accommodating (1) pedestrians who want to move safely and comfortably from point A to B (movement function); as well as (2) users who wish to rest, communicate, shop, eat, and enjoy life in a pleasant environment (place function). The aims of this study are to provide an overview of how the task of designing pedestrian facilities is addressed in international guidance material for urban street design, to compare this with scientific evidence on determinants of pedestrian activities, and to finally develop recommendations for advancing provisions for pedestrians. The results show that urban street design guidance is well advanced in measuring space requirements for known volumes of moving pedestrians, but less in planning pleasant street environments that encourage pedestrian movement and place activities. A stronger linkage to scientific evidence could improve guidance materials and better support urban street designers in their ambition to provide safe, comfortable and attractive street spaces that invite people to walk and to stay

Faire valoir ses droits à l'Aide Complémentaire Santé: Les résultats d'une expérimentation sociale

L'Aide complémentaire santé (ACS) ou « chèque santé » a été mise en place en 2005 pour inciter les ménages dont le niveau de vie se situe juste au-dessus du plafond CMU-C à acquérir une couverture complémentaire santé grâce à une subvention. Même si le nombre de bénéficiaires a lentement progressé depuis son introduction, le recours à l'ACS reste faible. Deux hypothèses peuvent expliquer cet état de fait : (1) le défaut d'information sur l'existence du dispositif, son fonctionnement et sur les démarches à entreprendre pour en bénéficier ; (2) un montant d'aide insuffisant, la complémentaire resterait trop chère même après déduction de l'aide. Afin de tester la validité de ces deux hypothèses, une expérimentation sociale contrôlée a été mise en place par l'université Paris-Dauphine à Lille auprès d'un échantillon de 4 209 assurés sociaux potentiellement éligibles à l'ACS. Un montant majoré d'aide ainsi qu'un accès différencié à l'information sur le dispositif ont été proposés de manière aléatoire à certains assurés. Les résultats montrent de manière robuste que la majoration du montant du « chèque santé » améliore légèrement le taux de recours à l'ACS et permet de mieux cibler les personnes effectivement éligibles. Toutefois, l'ACS reste un dispositif compliqué qui touche difficilement sa cible : au total, seuls 17 % des assurés ont fait une demande d'ACS. Seuls 9 % des assurés invités à participer à une réunion d'information y ont effectivement assisté, et l'invitation à cette réunion a largement découragé les autres assurés, annulant ainsi l'effet de la majoration du chèque. Enfin, seuls 55 % des assurés ayant déposé une demande ont reçu l'aide, les autres s'étant vu refuser l'aide en raison, le plus souvent, de ressources trop élevées. La difficulté à cibler la population éligible et l'incertitude importante sur l'éligibilité qui en résulte sont certainement des freins s'ajoutant à la complexité des démarches

Depressive disorders are associated with increased peripheral blood cell deformability: a cross-sectional case-control study (Mood-Morph)

Pathophysiological landmarks of depressive disorders are chronic low-grade inflammation and elevated glucocorticoid output. Both can potentially interfere with cytoskeleton organization, cell membrane bending and cell function, suggesting altered cell morpho-rheological properties like cell deformability and other cell mechanical features in depressive disorders. We performed a cross-sectional case-control study using the image-based morpho-rheological characterization of unmanipulated blood samples facilitating real-time deformability cytometry (RT-DC). Sixty-nine pre-screened individuals at high risk for depressive disorders and 70 matched healthy controls were included and clinically evaluated by Composite International Diagnostic Interview leading to lifetime and 12-month diagnoses. Facilitating deep learning on blood cell images, major blood cell types were classified and morpho-rheological parameters such as cell size and cell deformability of every individual cell was quantified. We found peripheral blood cells to be more deformable in patients with depressive disorders compared to controls, while cell size was not affected. Lifetime persistent depressive disorder was associated with increased cell deformability in monocytes and neutrophils, while in 12-month persistent depressive disorder erythrocytes deformed more. Lymphocytes were more deformable in 12-month major depressive disorder, while for lifetime major depressive disorder no differences could be identified. After correction for multiple testing, only associations for lifetime persistent depressive disorder remained significant. This is the first study analyzing morpho-rheological properties of entire blood cells and highlighting depressive disorders and in particular persistent depressive disorders to be associated with increased blood cell deformability. While all major blood cells tend to be more deformable, lymphocytes, monocytes, and neutrophils are mostly affected. This indicates that immune cell mechanical changes occur in depressive disorders, which might be predictive of persistent immune response