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Heart disease is the leading cause of death globally, and delivery of therapeutic cargo (e.g., particles loaded with proteins, drugs, cells, or genes) through direct injection into the myocardium is a promising clinical intervention. However, retention of deliverables to the contracting myocardium is low, with as much as 60 – 90% of payload being lost within 24 hours. Commercially-available injectable hydrogels, including Matrigel, have been hypothesized to increase payload retention, but have not yielded significant improvements in quantified analyses. Here, we assess a recombinant hydrogel composed of chemically modified hyaluronan and elastin-like protein (HELP) as an alternative injectable carrier to increase cargo retention. HELP is crosslinked using dynamic covalent bonds, and tuning the hyaluronan chemistry significantly alters hydrogel mechanical properties including stiffness, stress-relaxation rate, and ease of injectability through a needle or catheter. These materials can be injected even after complete crosslinking, extending the time window for surgical delivery. We show that HELP gels significantly improve in vivo retention of microsphere cargo compared to Matrigel, both 1 day and 7 days post-injection directly into the rat myocardium. These data suggest that HELP gels may assist with the clinical translation of therapeutic cargo designed for delivery into the contracting myocardium by preventing acute cargo loss.

Intrinsically disordered proteins and regions (IDPs and IDRs) and their importance in biology are becoming increasingly recognized in biology, biochemistry, molecular biology and chemistry textbooks, as well as in current protein science and structural biology curricula. We argue that the sequence → dynamic conformational ensemble → function principle is of equal importance as the classical sequence → structure → function paradigm. To highlight this point, we describe the IDPs and/or IDRs behind the discoveries associated with 17 Nobel Prizes, 11 in Physiology or Medicine and 6 in Chemistry. The Nobel Laureates themselves did not always mention that the proteins underlying the phenomena investigated in their award-winning studies are in fact IDPs or contain IDRs. In several cases, IDP- or IDR-based molecular functions have been elucidated, while in other instances, it is recognized that the respective protein(s) contain IDRs, but the specific IDR-based molecular functions have yet to be determined. To highlight the importance of IDPs and IDRs as general principle in biology, we present here illustrative examples of IDPs/IDRs in Nobel Prize-winning mechanisms and processes.

Heart disease is the leading cause of death globally, and delivery of therapeutic cargo (e.g. cells, proteins, drugs) through direct injection into the myocardium is a promising clinical intervention. However, retention of deliverables to the contracting myocardium is low, with as much as 60 - 90% of payload being lost within 24 hours. Commercially-available injectable hydrogels, including Matrigel, have been hypothesized to increase payload retention, but have not yielded significant improvements in quantified analyses. Here, we assess a recombinant hydrogel composed of chemically modified hyaluronan and elastin-like protein (HELP) as an alternative injectable carrier to increase cargo retention. HELP is crosslinked using dynamic covalent bonds, and tuning the hyaluronan chemistry significantly alters hydrogel mechanical properties including stiffness, stress-relaxation rate, and ease of injectability through a needle or catheter. These materials can be injected even after complete crosslinking, extending the time window for surgical delivery. We show that HELP gels significantly improve in vivo retention of microsphere cargo compared to Matrigel, both 1 day and 7 days post-injection directly into the rat myocardium. These data suggest that HELP gels may assist with the clinical translation of therapeutic cargo designed for delivery into the contracting myocardium by preventing acute cargo loss.

Resumen: La expansión urbana ha ampliado las distancias y tiempos de viaje de las personas que viven y trabajan en las ciudades. En el Área Metropolitana de Santiago de Chile sus habitantes menos favorecidos enfrentan profundos desafíos, pues tanto sus ingresos como los territorios donde residen revelan una menguada disponibilidad de capitales de movilidad. La presente investigación busca calcular y entender los distintos costos de la movilidad expresados en tiempo y en dinero, a partir de los viajes al trabajo como expresión de las desigualdades urbanas existentes en la ciudad. Se utilizan para esto las Encuestas de Caracterización Socio Económica (CASEN) del Ministerio de Desarrollo Social de 2015 y 2017, que incorporan preguntas sobre la movilidad de las personas. Desde un enfoque cuantitativo, se definen los costos monetarios mensuales de la movilidad de los hogares determinando su porcentaje en el ingreso monetario del hogar y se realiza un análisis complementario considerando distintas variables socioeconómicas. Los resultados evidencian profundas desigualdades debidas al mayor peso del costo del transporte público en los ingresos de los más vulnerables, hecho que se condice con mayores tiempos de viaje debido a la lejanía entre su residencia y los centros laborales, mayor desempleo y menor motorización privada.

International audience; In this work we formulate a Stackelberg Security Game that coordinates resources in a border patrol problem. In this security domain, resources from different precincts have to be paired to conduct patrols in the border due to logistic constraints. Given this structure, models that enumerate the pure defender strategies scale poorly. We describe the set of mixed strategies using a polynomial number of variables but exponentially many constraints that come from the matching polytope. We then include this description in a mixed integer formulation to compute the Strong Stackelberg Equilibrium efficiently with a branch and cut scheme. Since the optimal patrol solution is a probability distribution over the set of exponential size, we also introduce an efficient sampling method that can be used to deploy the security resources every shift. Our computational results evaluate the efficiency of the branch and cut scheme developed and the accuracy of the sampling method.

Self-healing materials represent a paradigm shift from traditional materials development, enabling intrinsic repair of functionality (such as strength) after a catastrophic failure as opposed to part replacement. Several healing mechanisms have been demonstrated in polymeric and ceramic materials, but few in metallic systems. This study demonstrates a novel liquid-assisted self-healing metal-matrix composite (MMC) designed to be capable of over 90% strength recovery after a healing cycle. The aluminum (Al)-based matrix is reinforced with continuous nickel-titanium (NiTi) shape-memory alloy (SMA) reinforcements. Using a tailored heat treatment for healing, a paired effect of crack closure from the SMA reinforcement and partial liquefaction of the matrix occurs. These effects result in a compressive force across the crack surface, and, coupled with increased diffusion rates from the liquefied matrix, produces consolidation and healing in the composite structure. This work provides experimental and computational evidence for the healing mechanism under both tensile and fatigue conditions.

Upper Cretaceous intrusives of limited extent crop out in the Coastal Cordillera near of Valdivia (39°48' S), 100 km west of the main topographic divide of the Andean Cordillera. Given that plutonic rocks of the same age crop out at the same latitudes in the high Andes the coastal intrusives emplaced in a forearc position in the upper plate of a subduction setting. They correspond to hypabyssal intrusives displaying mainly porphyritic texture and lithological variations with microtonalites (minor), porphyritic microgranodiorites (main) and microgranites. They intrude the Upper Paleozoic-Triassic accretionary complex of the Bahia Mansa Metamorphic Complex. These intrusives, that comprise the Chaihuín Pluton and minor stocks of porphyritic felsic rocks, have calc-alkaline affinities with metaluminous and peraluminous character. They are geochemically similar to the contemporaneous main arc-related plutonic rocks of the Gualletué Plutonic Group. The microgranitoids and dacitic rocks from Los Boldos, the low and Loncoche are peculiar because they show an apparently adakitic affinity in Sr/Y and LaN/YbN discriminant diagrams; nevertheless Sr contents of these rocks (<

In the past 10 years, the concept of public space has gradually become a new key topic in Chile’s urban planning debate. Most often linked to sustainable urban growth and sustainable mobility, the concept arises in a context of legal changes aiming to reinforce the street as a public space dedicated to all type of mobilities, including active modes of transport (walking and cycling). These recent legal transformations represent an important shift in Chile’s urban planning, establishing guidelines for the future in order to encourage sustainable mobility and increase public space quality and access in Chile’s cities. This integrated approach to urban development represents a clear tendency to promote a more cohesive society in a context of increasing urban complexity and environmental challenges. It recognizes spatial, socio-economic and environmental issues and aims to articulate urban planning with mobility by seeking a balanced distribution of urban functions in Chilean cities. Although at first glance this new approach seems positive, it is important to analyse these changes through the lens of Chile’s urban production, especially in the case of intermediate Chilean cities that, due to their scale, still have the possibility to redirect their development towards a more sustainable growth. We propose a critical analysis of urban public space production in intermediate Chilean cities. By defining streets as public spaces and enabling specific social practices in line with specific urban contexts, we are able to define streets as a social space dedicated to mobilities. From this position, under what type of conditions are these public spaces planned and designed? What social consequences or conflicts emerge through their implementation? These processes will be illustrated through examples of public space projects and policies developed in intermediate Chilean cities these past few years.

International audience; The Upper Jurassic volcanic rocks of the Pre-Cordillera and High Andes of northern Chile (26 - 31°S) represent a back-arc magmatic chain formed during an earlier stage of Andean subduction. After the Callovian, the back-arc basin gradually changed from marine to continental conditions and was characterized by basaltic to rhyolitic rocks erupted along two belts, parallel to the coeval arc. The western belt comprises the Picudo and Algarrobal formations, whereas the eastern belt comprises the Lagunillas Formation and the Quebrada Vicuñita Beds. New major and trace elements data, along with whole rock Sr, Nd and Pb isotopes are presented for these volcanic belts and compared to the geochemical features of the Jurassic and Early Cretaceous arc magmatism. Ar-Ar and U-Pb ages constrain the back arc volcanism to have evolved between 163.9 ± 1.4 and 148.9 ± 1.2 Ma.Rocks belonging to the western belt have steep multi-element patterns and low concentrations of HREE, suggesting the presence of garnet in the source, and a more radiogenic isotopic composition than the arc magmatism. Parental magmas of these back-arc lavas would have been generated through melting of a depleted mantle, although less depleted than the sub-arc mantle, and interacted with minor amounts of Paleozoic crust. The geochemical composition of the rocks belonging to the eastern belt is more heterogeneous and suggests involvement of different magmatic sources, including depleted mantle as well as an OIB-type mantle within the wedge. In spite the fact that the Jurassic Andean arc was built over a continental plate, the architecture of the volcanic chains and geochemical variations observed among the arc and back-arc rocks in northern Chile resemble those in modern island arcs, and thus support the hypothesis that early Andean subduction developed under extensional tectonic conditions.

International audience; The role of daily mobility as a socio-spatial inequalities factor is a key issue in Latin America and is partly attributable to urbanisation patterns on this continent: a rather advanced urban transition, low density and wide spread millionaire metropolises, deep social inequalities, high socio-residential segregation, and an inequitable work distribution within the city. The purpose of this paper is to investigate the relation between daily trips to work and socio-spatial inequalities in three contrasted metropolises (Bogotá, Santiago, São Paulo). We demonstrate that beyond the social hierarchy effect, the territorial effect is determining on people’s daily mobility conditions.; La question du rôle des mobilités quotidiennes comme facteur d’inégalités socio-spatiales se pose avec une grande acuité en Amérique latine, du fait des caractéristiques de l’urbanisation sur ce continent : une transition urbaine bien avancée, des métropoles « millionnaires » très étalées et peu denses, marquées par de profondes inégalités sociales, une très forte ségrégation socio-résidentielle, ainsi qu’une inéquitable répartition des emplois dans la ville. L’objectif est d’explorer ici le lien entre les déplacements domicile-travail et les inégalités socio-spatiales dans trois métropoles contrastées (Bogotá, Santiago, São Paulo). Nous montrons qu’au-delà du simple effet de la hiérarchie sociale, l’effet territorial est déterminant sur les conditions de mobilité quotidienne des citadins.

The N–S oriented Coastal Cordillera of South Central Chile shows marked lithological contrasts along strike at ∼38°S. Here, the sinistral NW–SE-striking Lanalhue Fault Zone ( nomen novum ) juxtaposes Permo-Carboniferous magmatic arc granitoids and associated, frontally accreted metasediments (Eastern Series) in the northeast with a Late Carboniferous to Triassic basal-accretionary forearc wedge complex (Western Series) in the southwest. The fault is interpreted as an initially ductile deformation zone with divergent character, located in the eastern flank of the basally growing, upwarping, and exhuming Western Series. It was later transformed and reactivated as a semiductile to brittle sinistral transform fault. Rb–Sr data and fluid inclusion studies of late-stage fault-related mineralizations revealed Early Permian ages between 280 and 270 Ma for fault activity, with subsequent minor erosion. Regionally, crystallization of arc intrusives and related metamorphism occurred between ∼306 and ∼286 Ma, preceded by early increments of convergence-related deformation. Basal Western Series accretion started at >290 Ma and lasted to ∼250 Ma. North of the Lanalhue fault, Late Paleozoic magmatic arc granitoids are nearly 100 km closer to the present day Andean trench than further south. We hypothesize that this marked difference in paleo-forearc width is due to an Early Permian period of subduction erosion north of 38°S, contrasting with ongoing accretion further south, which kinematically triggered the evolution of the Lanalhue Fault Zone. Permo-Triassic margin segmentation was due to differential forearc accretion and denudation characteristics, and is now expressed in contrasting lithologies and metamorphic signatures in todays Andean forearc region north and south of the Lanalhue Fault Zone.

unque comparten patrones comunes con otras areas metropolitanas de America Latina, las transformaciones de Santiago de Chile tienen como rasgo distintivo los profundos cambios de orden politico, economico y regulatorio que se han ido produciendo desde finales de la decada de los setenta, muchos de los cuales no tienen precedente en otras ciudades de Latinoamerica. El transporte urbano, precisamente, ha estado de manera frecuente en la palestra internacional desde el tiempo en que el gobierno militar dic-taminara la experiencia unica en el mundo de desregulacion total del sistema, durante los anos ’70. Las correcciones introducidas mas tarde, en democracia, a traves de sistemas competitivos de otorgamiento de concesiones, tambien crearon un hito en la experiencia mundial y, especialmente, latinoamericana, por lo innovador y profundo de las practicas adoptadas y por los resultados obte-nidos. Transantiago fue concebido en medio de la misma expectativa nacional e internacional y sus resultados tambien han dado la vuelta al mundo. Sin embargo, en este caso ellos han sorprendido por lo inesperados y por lo profundamente ne-gativos.Las causas de los problemas de Transantiago tienen muchas vertientes. No obstante, en su ori-gen se encuentran una serie de aspectos vinculados a la organizacion institucional y a las soluciones de gobernabilidad, que desde ya se constituyen como aspectos limitantes de la gestion, y cuyos efectos se veran con posterioridad. De esta manera, esta nota analiza las variables institucionales de Transantiago desde dos puntos de vista. Por una parte, las ca-pacidades de gestion y organizacion institucional sectorial y, por otra, las limitantes en la gestion y la institucionalidad territorial.

In south-central Chile (36–42° S), the western edge of South America has evolved as an active margin since the Pennsylvanian (∼305 Ma). Active margins are considered as sites of both potential continental growth and continental destruction. Continental growth in a margin setting can proceed by accretionary offscraping of juvenile material from the oceanic plate and by magmatic additions, whereas net mass loss can be achieved by subducting continental material, delamination, and chemical weathering. In southcentral Chile, margin evolution was never interrupted by island-arc accretion or continental collision. Thus, the area provides an excellent field laboratory for studying mass flux through a long-term, persistent, convergent-margin system.

Forearc accretionary wedges are cyclic systems in which material is frontally and/or basally accreted. Material cycling involves underthrusting, subduction, underplating, exhumation, erosion, transfer to the trench and underthrusting again. In this study we present a novel, tectonochronologic approach to constrain long-term exhumation rates of basally accreted wedge complexes, based on isotopic dating of structural features, on petrological data and sandbox analogue simulations. Congruence between the structural inventory in nature and structures generated in scaled sandbox experiments allows detailed insights into wedge dynamics. For the present-day surface material of the paleoaccretionary wedge of South-Central Chile (Valdivia area, 40°S), published U–Pb ages of detrital zircon place a maximum age of ∼278 Ma for subduction. Prograde metamorphism at transitional greenschist to blueschist facies conditions (420 °C, 8–9 kbar) was immediately followed by progressive penetrative deformation associated with basal accretion, dated at ∼250–245 Ma using Rb/Sr internal mineral isochrons. The accretion process involved duplex tectonics and antiformal stacking, with formation of near-horizontal mylonitic shear zones at around 241 Ma. Continuous basal accretion at depth gave rise to an extensional tectonic regime at higher structural levels. Both semi-ductile, small-scale extensional shear zones and post-kinematic vein mineralizations yield Rb/Sr ages of ∼235 Ma. Tension gashes, representing the latest isotopically dateable stage of structural evolution, were formed at ∼210 Ma, at conditions of ∼230 °C at 1.5–3 kbar, as constrained by fluid inclusion data. Zircon fission track data indicate final cooling to below ∼200 °C at 186±24 Ma. The results suggest continuous basal accretion for at least 50 Ma, with long-term average exhumation rates of 0.6±0.2 mm/a, most probably outbalanced by similar long-term average erosion rates. Changing plate boundary conditions at about 210–200 Ma terminated the accretion process, as evident from a dramatic decrease of exhumation rates at that time. Since then, the paleoaccretionary wedge remained stably in place despite its delicate geotectonic position within the Andean active margin. The tectonochronologic approach complements thermochronologic and geomorphologic methods of exhumation research as it provides direct constraints on mass flux rates even for high-temperature increments of P–T trajectories.

This paper presents new insights on the evolution of continental crust in a segment of the southern Central Andes (Chile–Argentina; ca. 36–41 °S) from compositional and isotopic age data of metamorphic and magmatic rocks. The crustal reservoir of this long-standing active continental margin is characterized by the isotopic composition of Paleozoic (meta)sedimentary rocks which is typical of Proterozoic continental crust (Nd model ages 1.6–2.1 Ga; isotopic composition at ca. 300 Ma, the time of formation of the late Paleozoic granites: 87Sr/86Sr ca. 0.71–0.72; 143Nd/144Nd ca. 0.5117–0.5120; 207Pb/204Pb ca. 15.64–15.70, 206Pb/204Pb ca. 18.2–18.6, 208Pb/204Pb ca. 37.2–38.5). The late Paleozoic and late Triassic granitoids (ca. 220 Ma) contain 30–80% of this material assuming a mantle endmember with the isotopic composition of Pacific MORB. The proposed mechanism of magma generation in the late Paleozoic and Triassic granitoids is assimilation of crustal material by mantle derived melts, i.e. mixing between crustal and mantle melts. The isotopic composition of the Paleozoic rocks in the southern Central Andes indicates a coherent evolution of the western Gondwana margin (21–41°S) during the Paleozoic mainly recycling Proterozoic material by sedimentation, metamorphism and magmatism. The magmatism of the Andean cycle represents important additions of juvenile material to the crust. The Mesozoic to Tertiary intrusions have a relatively uniform isotopic composition (87Sr/86Sri ca. 0.7036–0.7066; 143Nd/144Ndi ca. 0.5125–0.5129; Pbi 207Pb/204Pb ca. 15.60–15.65, 206Pb/204Pb ca. 18.0–18.5, 208Pb/204Pb ca. 37.2–38.4) indicating only small contributions of the crustal reservoir (ca. 5–10%) to mantle derived magma with presumed MORB isotope signature. The proposed main mechanism of crustal contribution in these rocks is mixing of continent-derived sediments into the mantle wedge.

Background: Penicillin and third generation cephalosporin resistant pneumococcal isolates have emerged in Chile, mainly in the pediatric population. These isolates complicate therapeutic alternatives, specially among patients with central nervous system infections. Aim: To assess the frequency of penicillin and third generation cephalosporin resistance among isolates obtained from pediatric patients with invasive pneumococcal infections, and to study serotypes and clinical risk factors associated with resistance. Material and methods: Microbiological isolates obtained from children between April 1994 and May 1999 with pneumococcal invasive infections, were serotyped and analyzed according to their susceptibility to penicillin and cefotaxime by E-test and broth microdilution testing. Potential risk factors studied included patient's age, previous antibiotic use or admissions, comorbidity, and serotypes. Results: Seventy eight patients were studied. Penicillin-resistant pneumococcal isolates were detected in 35.9% of cases (21.8% with intermediate and 14.1% with high level resistance) without significant variation among different clinical conditions. Most of the high level penicillin-resistant pneumoccocal isolates had MIC ≥4 µg/mL (8 out of 11 strains). One third of penicillin-resistant isolates also expressed cefotaxime resistance. Multivariate analysis indicated an age ≤36 months (OR=6.8; IC 95%: 1.4 to 33.5) and serotype 14 (OR=6.3; IC 95%: 1.7 to 23.3) as factors associated with penicillin resistance. Conclusions: One third of the invasive pneumococcal isolates obtained from pediatric patients were resistant to penicillin. Risk factors involved a younger age and pneumococcal isolates belonging to serotype 14 (Rev Méd Chile 2002; 130: 26-34)

Contrary to the assumptions/ postulates of a generalized mobility of society and the weakening of the territorial dimension, this research demonstrates the importance of the proximity of the territory - home and neighborhood - as a support place, a very suitable and strategic place to deal with the tensions modern life brings. Indeed, individuals seek for a balance that takes the form of an oscillation between nomadism and anchorage, which proves that mobility rather than opposing, articulates with the anchorage in the proximity.Gathering information from the Geography and Ethnography, research was carried out in three neighborhoods of the city of Santiago de Chile (different neighborhoods in terms of location and socioeconomic composition), the investigation consisted on observations and repeated and prolonged visits to the places mentioned and the execution of 51 in-depth conversations with its inhabitants. It is suggested that they seek a sociospacial insertion marked by proximity as a way to cope with an increasing demand for mobility, showing how the house and the neighborhood becomes a substantial anchor point of lifestyles.This research argues that is the anchorage in the territory of proximity that makes it possible to explore the city at various scales. Going away, traveling, moving long distances does not necessarily imply a rupture with the place of origin, with family, with the everyday environment, however, is the support in the proximity which allows many daily mobility practices to be made. Three archetypes of proximity and support were identified in this research: the locals, the metropolitans and the retracted, showing that the role of neighborhood scale exists as an oscillation between rootedness and mobility, between rejection and confinement., Contrariamente a los postulados de una movilidad generalizada de la sociedad y el debilitamiento de la dimensión territorial, se demuestra en esta investigación la importancia del territorio de proximidad – casa y barrio – como espacio soporte, lugar propio y estratégico para hacer frente a las tensiones que trae la modernidad. En efecto, los individuos buscan un equilibrio que toma la forma de una oscilación entre nomadismo y anclaje, que da cuenta que la movilidad más que oponerse se articula con el anclaje en la proximidad.Reuniendo los aportes de la Geografía y la Etnografía se realizó una investigación en tres barrios de la ciudad de Santiago de Chile (barrios distintos en términos de localización y composición socioeconómica), que consistió en observaciones y visitas reiteradas y prolongadas a dichos terrenos así como la realización de 51 conversaciones a profundidad con sus habitantes. Se plantea que ellos buscan una inserción socioespacial marcada por la proximidad como forma de hacer frente a una exigencia cada vez mayor a la movilidad, demostrando como la casa y el barrio se constituye en un punto de anclaje substancial de los modos de vida.Esta investigación sostiene que es el anclaje en el territorio de proximidad lo que hace posible la exploración de la ciudad en sus diversas escalas. Ir lejos, viajar, desplazarse largas distancias no implica necesariamente una ruptura con el lugar de origen, con la familia, con el medio ambiente cotidiano, por el contrario, es el soporte en la proximidad lo que permite que muchas prácticas de movilidad cotidiana puedan realizarse. Tres arquetipos de la proximidad como soporte fueron identificados en esta investigación: los locales, los metropolitanos y los replegados, mostrando que el rol de la escala barrial existe como una oscilación entre arraigo y movilidad, entre rechazo y confinamiento., Face aux hypothèses de mobilité généralisée de la société et d’affaiblissement de la dimension territoriale, il est démontré dans cette recherche l’importance du territoire de proximité – la maison et le quartier – en tant que support, et lieu personnel et stratégique permettant aux individus de surmonter les tensions qu’entraîne la modernité. Les individus sont, en effet, à la recherche d’un équilibre oscillant entre nomadisme et ancrage. Ainsi, il apparaît que la mobilité, bien loin de s’opposer, trouve à s’articuler avec l’ancrage dans la proximité.En concentrant les apports de la Géographie et de l’Ethnographie, une recherche a pu être menée dans trois quartiers de la ville de Santiago du Chili (quartiers qui se différencient par leur emplacement et par la composition socio-économique de leurs habitants). Cette recherche a été rendue possible grâce aux observations et aux visites réitérées et prolongées sur les différents terrains d’étude ainsi qu’à la réalisation de 51 entretiens approfondis avec les habitants de ces quartiers.Il est avancé dans ce travail que ces derniers cherchent à s’insérer socio-spatialement en s’inscrivant dans la proximité afin de faire face à une exigence toujours plus forte de mobilité. A cette fin, il est démontré comment la maison et le quartier deviennent un point d’ancrage substantiel des différents modes de vie.Cette recherche soutient que c’est l’ancrage dans le territoire de proximité qui rend possible l’exploration des différentes échelles de la ville.Aller loin, voyager, se déplacer sur de longues distances n’implique pas nécessairement une rupture avec le lieu d’origine, avec la famille, ou avec l’environnement quotidien. Au contraire, c’est le support dans la proximité qui permet à de nombreuses pratiques de mobilité de pouvoir se réaliser.Trois archétypes de la proximité en tant que support ont été identifiés dans cette recherche : les locaux, les métropolitains et les repliés, démontrant ainsi que le rôle de l’échelle du quartier prends la forme d’une oscillation entre enracinement et mobilité, entre rejet et confinement.