Green networks in carless cities: reusing infrastructure as public open space in sustainable urban systems

As global urbanization increases, cities face the challenge of becoming sustainable. To reduce emissions and traffic congestion, cities must rethink their circulation systems and rely less on private cars. This change would improve one of the urban quality of life aspects by upgrading public spaces, more specifically urban green spaces, by linking them to an urban green network. As the space for private cars will gradually decrease, the existing vehicular system can be reused for pedestrian purposes.This paper addresses the transformation of existing road networks into a system of public green spaces, one that will connect the urban local parks to the green lungs of the city. Through a theoretical framework and several examples, the report examines four key aspects for completing this transformation: urban sustainability, open space as network, transportation and circulation, and reusing infrastructure. Two Montreal projects, used as case studies, illuminate ways of reusing existing infrastructure. Last, based on the theoretical framework and the case studies, recommendations for further development and implications are suggested.This report draws from urban design theories that changed cities through counter process design, in order to learn from those experiences and introduce a new contour of sustainability. The paper suggests another layer in the attempt to address the challenges to develop sustainable cities without compromising the ability of future generations to meet their own needs.Au fur et à mesure que l'urbanisation mondiale augmente, les villes sont confrontées au défi de devenir durable. Afin de réduire les émissions de CO2 et la congestion du trafic, les villes doivent repenser leurs systèmes de circulation et moins compter sur les voitures individuelles. Ces changements permettraient d'améliorer l'un des aspects de la qualité de vie en milieu urbain par la transformation des espaces publics, et plus particulièrement des espaces verts urbains, en les reliant au sein d’un réseau vert urbain. Comme l'espace pour les voitures diminuera, les voies véhiculaires existantes pourront être réutilisées pour les piétons.Ce rapport traite de la transformation des réseaux routiers existants en un système d'espaces verts publics, qui reliera les parcs urbains locaux aux poumons verts de la ville. Par le biais d’un cadre théoriques et de plusieurs exemples, le rapport examine quatre aspects essentiels pour remplir cette transformation: la durabilité urbaine, les réseaux d’espaces publics, le transport et la circulation, et la réutilisation des infrastructures. Deux projets à Montréal, utilisés comme études de cas, éclairent les façons de réutiliser l'infrastructure existante. Enfin, sur la base du cadre théorique et des études de cas, des impacts sont discutés et des recommandations pour la poursuite du développement sont proposées.Ce rapport se fonde sur des théories de conception sociale qui sont nées en réaction au processus urbains existants. Il apprend de ces expériences pour présenter aspect supplémentaire de la durabilité urbaine. Le document suggère une nouvelle couche dans la tentative de relever les défis de développement des villes durables sans compromettre la capacité des générations futures à satisfaire leurs propres besoins

Developmental Cascades Link Maternal–Newborn Skin-to-Skin Contact with Young Adults’ Psychological Symptoms, Oxytocin, and Immunity; Charting Mechanisms of Developmental Continuity from Birth to Adulthood

Premature birth disrupts the continuity of maternal–newborn bodily contact, which underpins the development of physiological and behavioral support systems. Utilizing a unique cohort of mother–preterm dyads who received skin-to-skin contact (Kangaroo Care, KC) versus controls, and following them to adulthood, we examined how a touch-based neonatal intervention impacts three adult outcomes; anxiety/depressive symptoms, oxytocin, and secretory immunoglobulin A (s-IgA), a biomarker of the immune system. Consistent with dynamic systems’ theory, we found that links from KC to adult outcomes were indirect, mediated by its effects on maternal mood, child attention and executive functions, and mother–child synchrony across development. These improvements shaped adult outcomes via three mechanisms; (a) “sensitive periods”, where the infancy improvement directly links with an outcome, for instance, infant attention linked with higher oxytocin and lower s-IgA; (b) “step-by-step continuity”, where the infancy improvement triggers iterative changes across development, gradually shaping an outcome; for instance, mother–infant synchrony was stable across development and predicted lower anxiety/depressive symptoms; and (c) “inclusive mutual-influences”, describing cross-time associations between maternal, child, and dyadic factors; for instance, from maternal mood to child executive functions and back. Findings highlight the long-term impact of a birth intervention across development and provide valuable insights on the mechanisms of “developmental continuity”, among the key topics in developmental research

Breast milk oxytocin and s-IgA modulate infant biomarkers and social engagement; The role of maternal anxiety

Breastfeeding has long been known to improve infants' health and mental development and to enhance the mother-infant bond, but much less research focused on the biological composition of breast milk and its associations with the infant's biomarkers and social development. In this exploratory study, we measured oxytocin (OT) and secretory immunoglobulin-A (s-IgA), the most abundant antibody in breast milk, and evaluated their associations with the same biomarkers in infant saliva and, consequently, with infant social engagement behavior. Fifty-five mother-infant dyads were home-visit and OT and s-IgA were assessed from breast milk and from infant saliva before and after a free-play interaction. Infant social behavior was coded offline using the Coding Interactive Behavior (CIB) and maternal anxiety self-reported. A path model revealed that mother's breast milk s-IgA impacted child social engagement via its links with child OT. In parallel, maternal breast milk OT was linked with infant social behavior through its association with the infant's immunity. This path was moderated by maternal anxiety; only in cases of high anxiety breast milk OT was positively connected to infant s-IgA. Our study, the first to measure OT and s-IgA in both breast milk and infant saliva in relation to observed social behavior, underscores the need for much further research on the dynamic interplay between breast milk composition, infant biomarkers, maternal mental health, and infant social outcomes. Results may suggest that biological systems in breast milk integrate to prepare infants to function in their social ecology through bio-behavioral feedback loops that signal the degree of stress in the environment

Sublinear bounds for randomized leader election

This paper concerns {\em randomized} leader election in synchronous distributed networks. A distributed leader election algorithm is presented for complete $n$-node networks that runs in O(1) rounds and (with high probability) uses only $O(\sqrt{n}\log^{3/2} n)$ messages to elect a unique leader (with high probability). When considering the "explicit" variant of leader election where eventually every node knows the identity of the leader, our algorithm yields the asymptotically optimal bounds of O(1) rounds and O(n) messages. This algorithm is then extended to one solving leader election on any connected non-bipartite $n$-node graph $G$ in $O(\tau(G))$ time and $O(\tau(G)\sqrt{n}\log^{3/2} n)$ messages, where $\tau(G)$ is the mixing time of a random walk on $G$. The above result implies highly efficient (sublinear running time and messages) leader election algorithms for networks with small mixing times, such as expanders and hypercubes. In contrast, previous leader election algorithms had at least linear message complexity even in complete graphs. Moreover, super-linear message lower bounds are known for time-efficient {\em deterministic} leader election algorithms. Finally, we present an almost matching lower bound for randomized leader election, showing that $\Omega(\sqrt n)$ messages are needed for any leader election algorithm that succeeds with probability at least 1/e + \eps, for any small constant \eps > 0. We view our results as a step towards understanding the randomized complexity ofleader election in distributed networks.Comment: Best Paper Award winner at ICDCN 2013, CDCN 2013 14th International Conference on Distributed Computing and Networking. Tata Institute of Fundamental Research, Mumbai, Indi