growing urban bicycle networks

Combinatorica 7, 3538 (1987). 14, 620634 (2020). Sensys Networks is headquartered in Berkeley, California, and is led by industry veterans who bring years of experience in wireless communications, carrier grade infrastructure, e acquired and pre-processed the data with input from S.M. Article To test how much cities improve their bicycle layers using these four algorithms, we define two metrics on the bicycle layer that operationalize the notion of connectedness: (i) nLCC = NLCC/N, the fraction of nodes from the bicycle infrastructure inside the largest connected component (NLCC) compared with the total number of nodes from the same type of infrastructure (N), and (ii) LCC = LLCC/L, the fraction of link kilometres inside the bicycle infrastructure largest connected component (LLCC) compared with the total number of link kilometres in the bicycle network (L). Urban transportation networks, from pavements and bicycle paths to streets and railways, provide the backbone for movement and . Our approach takes into account the currently available bicycle infrastructure and uses an algorithmic process to improve the network by finding the most important missing links step by step. Barthlemy, M. Spatial networks. Correspondence to It decreases approximately linearly with the bicycle networks growth, from \(D \approx 0.8\) to \(D \approx 0.6\), as the network is grown using the betweenness strategy (red curve in Fig. This rapid increase shows that the city can easily improve its bicycle infrastructure with small investments. These datasets are of high quality [24,25] in terms of correspondence with municipal open data [26] and completeness: more than 80% of the world is covered by OSM [27]. This result holds for all analysed cities (see electronic supplementary material). and M.S. Local efficiency measures local fault tolerance and therefore operationalizes the concept of resilience on a local level. Tens of thousands of datapoints sourced by public institutions and digital devices belonging to private companies that have spread across Berlin over the last ten years are utilized, unveiling the distribution of and correlation between datasets and the citys bikeway network at an unprecedented threshold. Sci Rep 12, 6765 (2022). (Map plots, left) Networks representing various layers of transport infrastructure (pedestrian paths, bicycle paths, rail lines and streets) for Copenhagen and London, with data from OpenStreetMap. 4F, is similar to coverage but more pronounced for random and betweenness growth. Formally, we write =ijbij/ijsij, where ijsij is the average car-route distance, and ijbij is the average length of the shortest bike-route between i and j. Urban Des. To make . Data-driven strategies for optimal bicycle network growth. Geogr. The three thick curves show the change of the metrics with growth following the three strategies (betweenness, closeness, or random) for grid seeds. Here we explore systematically the topologicallimitations of urban bicycle network development. A few of the considered cities do not have rail stations. International Journal of Sustainable Transportation, Abstract Over the last two decades, cycling has seen a rise in popularity in North American cities, which are continuously expanding their bicycle networks. Here we explore systematically the topologi. ISPRS Int. (d) Kilometres gain (GLCC). To improve this situation, it would be necessary to create links in the network that act as redundant paths. Environ. 115, 142156 (2015). Growing networks from. To make urban transport sustainable, cities are increasingly investing to develop their bicycle networks. and T.P., and performed the simulations. 510. (, Synthetic bicycle networks perform several times better than existing ones. Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ADS (3) Use random growth for fastest coverage but low directness, connectedness, and efficiency. T.P. (e) Bicycle-car directness (). It is a first step towards a quantitative consolidation of bicycle infrastructure development that can become valuable for urban planners and stakeholders. Res. . Nature 587, 402407 (2020). PDF - Urban transportation networks, from sidewalks and bicycle paths to streets and rail lines, provide the backbone for movement and socioeconomic life in cities. Med. acknowledges support by the European Commission through H2020 projects HumanE AI (G.A. Article However, bicycle networks are typically developed in a slow, piecewise process that leaves open a large number of gaps. Figure 1. Wind Cave Trail is 3, starting with the street network and the seed points. The political economy of car dependence: A systems of provision approach. 65, 126139 (2017). 2020 New and atypical combinations: An assessment of novelty and interdisciplinarity , M. Fontana, M. Iori, F. Montobbio, & R. Sinatra, (. MATH For closeness we find almost the same result as for betweenness, only with notably worse coverage which is to be expected given how closeness grows the covered area as slowly as possible. Step (3) Order by growth strategy Each of three growth strategies is used to order the greedy triangulation links from the strategys 0-quantile (empty graph) to its 1-quantile (full triangulation), resulting in a sequence of growth stages. See, Global Designing Cities Initiative and National Association of City Transportation Officials. This infrastructure fragmentation in the bicycle layer poses a challenge for a citys multimodal mobility options [40] and for the safety of its cycling citizens [41,42]. Route infrastructure and the risk of injuries to bicyclists: A case-crossover study. For 62 cities we study different variations of growing a synthetic bicycle network between an arbitrary set of points routed on the urban street network. The propensity to cycle tool: An open source online system for sustainable transport planning. Our main result focuses on directness because it is the most important metric for bicycle network planning apart from connectivity: It is the key metric to quantify network quality14, and it is the best predictor or quantifiable policy aspect for adoption of cycling53,54. A networks global efficiency is defined as47: A networks local efficiency is defined as the average of global efficiencies \(E_{\mathrm {glob}} (i)\) over each node i and its neighbors. Rail station seeds consist of all railway and metro stations. PubMed AU - Mimar, Sayat. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. 68, 149159 (2018). The use of data-driven algorithms to identify crucially missing links in bicycle infrastructure has the potential to improve the mobility infrastructure of cities efficiently and economically. A systematic exploration of city-wide, comprehensive development strategies is therefore urgently needed. Figure 2c shows how this measure improves in a similarly explosive way: with an investment of only 20 km (5.9% of the existing infrastructure), the largest connected component will contain 80% of the original bicycle infrastructure. (a) Schematic of algorithms to improve bicycle network infrastructure: Largest-to-Closest (L2C) finds the largest component and connects it with the closest one; Largest-to-Second (L2S) connects the largest component with the second largest; Closest-Connected (CC) connects the two closest components; and Random-to-Closest (R2C) picks a random component and connects it to the closest. Commun. This assumption roughly translates to a reduction of speed limits for cars along the affected road sections by a factor of 5, for example from \(50\,\mathrm {km/h}\) to \(10\,\mathrm {km/h}\) or from \(30\,\mathrm {km/h}\) to \(6\,\mathrm {km/h}\). Although scattered efforts in this direction have shown preliminary success, a quantitative framework for developing and assessing systematic strategies is missing [16]. Google Scholar. The system in Almetyevsk is dockless with about 300 pre-marked parking lots across the town where the bicycles must be left after use. In particular, a sole focus on electric vehicles is counterproductive and active travel should be a cornerstone of sustainability strategies, policies and planning9. However, we also tested our algorithms on a combination of bicycle infrastructure plus streets for which the maximum speed is 30 km h1, following common best-practice reasoning that low speed limits can make streets safe for cycling [39]. Improving the connectivity of bicycle lanes and paths improves not only the network itself, but also promotes the use of bicycles as means of transportation in a city, improving the health of its inhabitants [53]. We consider this extension an interesting line of future research in the challenge of developing optimal data-driven strategies of transport network growth, potentially informed by theoretical frameworks such as optimal percolation [50,51]. Measures in (be) are plotted as a function of the sum of added links in kilometres, for the case of Budapest (for all cities, see electronic supplementary material, figure SI.1). We downloaded existing street and bicycle networks for 62 cities from OpenStreetMap (OSM) on 2021-02-26 using OSMnx43. The authors declare no competing interests. rep. (Directorate-General for the Environment, 2004). And are there fundamental topological limitations for developing a bicycle network? For protected infrastructure, Fig. We measure several network metrics to assess the quality of the synthetically grown networks and to compare them with existing bicycle networks. It creates an approximatively shortest and locally dense planar network46, and a connected, cohesive, and resilient network solution minimizing investment, therefore satifsying both traveler and investor demands, Fig. However, even bicycle-friendly cities like Copenhagen have over 300 disconnected bicycle path componentssee the connected component size distribution P(Ncc) in figure 1. The results of these additional simulations are available in the electronic supplementary material; they do not differ significantly from the case of designated bicycle infrastructure presented below, as the developed algorithms follow the same rules to connect the multiple components in both cases of segregated bicycle infrastructure only and of included bikeable streets. However, prevailing bicycle network development follows a slow and piecewise process, without taking into account the structural complexity of transportation networks. Shown are grid points, alternatively we investigated rail stations. We find no clear effect for growth by closeness (dashed line). Appl. Even at \(q_{B}=0.20\) there is almost 70% overlap, Fig. PubMed Central ( A, Synthetic bicycle networks perform several, Synthetic bicycle networks perform several times better than existing ones. 4D), while the local efficiency decreases negligibly from \(E_{\mathrm {loc}} \approx 0.11\) to \(E_{\mathrm {loc}} \approx 0.10\) (red curve in Fig. Environ. Open Sci. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. Cycling is a promising solution to unsustainable car-centric urban transport systems. The length of the LCC, Fig. The three thick curves show, Network consolidation: Bicycle network growth, Network consolidation: Bicycle network growth has a dip of decreasing directness. Given this strong constraint, we find the metric that is most affected is directness. Growing urban bicycle networks. A cohesive network should also be resilient, see below, which excludes pathological cases like the minimum spanning tree. A demand-driven inverse percolation approach is proposed to generate families of efficient bike path networks taking into account cyclist demand and safety preferences, and may enable quantitative evaluation of the structure of current and planned cycling networks, and support the demand- driven design of efficient infrastructures. We nd initially decreasing returns on investment until a critical threshold, posing fundamental consequences to sustainable urban planning Zeng, G. et al. Behaviour change campaigns; Bike Share Schemes; Cycling Data Collection; Fast Cycling Routes; Intermodality; SUMP - sustainable Urban Mobility Plan; EuroVelo; Velo-city. Directness starts lower for closeness growth, around \(D \approx 0.59\) but quickly overtakes the other strategies at the 0.05-quantile. The anisotropy factor is defined by the ratio. EPJ Data Sci. We find initially decreasing returns on investment until a critical threshold, posing fundamental consequences to sustainable urban planning: Cities must invest into bicycle networks with the . Although such strategies make sense in cities with already well established bicycle infrastructure, they are less useful in most other cities. Instead, if city planners were to develop and implement bicycle networks holistically, considering a city-wide rather than piece-wise local approach, much higher quality infrastructure could be derived to the benefit of the residents. To predict with confidence, plan for freedom. and M.S. However, prevailing bicycle network development follows a slow and piecewise process, without taking into account the structural complexity of transportation networks. Further, our proposed approach helps implement a more connected transport network which can improve the possibilities for multimodal transport. Mahfouz, H., Arcaute, E. & Lovelace, R. A road segment prioritization approach for cycling infrastructure. European Commission. For example, GLCC = 1.5 means that the algorithm has increased the largest connected components original size by 150%. Our process of growing synthetic bicycle networks consists of four steps, Fig. Step (1) Seed points: A set of seed points (orange dots) is snapped to the intersections of the street network. In the past cities were built in scale more suitable for person's perception using local methods. PrietoCuriel, R., GonzlezRamrez, H., QuionesDomnguez, M. & OrjuelaMendoza, J. P. A paradox of traffic and extra cars in a city as a collective behaviour. It is no surprise that car-centric cities have a highly fragmented bicycle infrastructure: for example, London has more than 3000 disconnected bicycle infrastructure segments. Lovelace, R. et al. Bollobs, B. Res. The code downloads and pre-processes data from OpenStreetMap, prepares points of interest, runs simulations, measures and saves the results, creates videos and plots. and M.S. L.G.N.O. Despite the importance of these aspects, a transport networks geometry is its most fundamental limitation59 which is the reason we explored it first. Studying the resulting networks we found a consistent critical threshold affecting directness in all cities and global efficiency in some of them, for the two most realistic strategies of growth by betweenness and random growth. Transp. Epub 2016 Sep 23. Quercia, D., Schifanella, R. & Aiello, L.M. Proceedings of the 25th ACM Conference on Hypertext and Social Media, 116125 (2014). helped supervise the project. Google Scholar. Carstensen, T. A., Olafsson, A. S., Bech, N. M., Poulsen, T. S. & Zhao, C. The spatio-temporal development of Copenhagens bicycle infrastructure 19122013. Regions Germany Bavaria Gunzenhausen Cycling routes and bike maps in and around. 7C. This approach is the most local approach possible and leads to a linear expansion of a dense as possible network from the topological city center. Article & Thomason, A. G. Threshold functions. Once this threshold is reached, the quality improves dramatically, to an extent which depends on the specific growth strategy. (2022). We first specify a threshold \(\theta\) and identify the \(N_{\theta }\) nodes with high betweenness above the \(\theta\)-th percentile. Rec. Most modern cities have followed a car-centric development in the twentieth century [1] and are today allocating a privileged amount of urban space to automobile traffic [2,3]. Pollut. The results of this measurement show a wide range of effects: cities with an already high coverage above 80% (Amsterdam, Copenhagen) reach near instantly 100%, cities with an intermediate coverage (Manhattan, Bogota, Budapest) follow a more linear progression per added kilometre, while underdeveloped or sprawling cities (LA, London, Jakarta) show negligible growth (electronic supplementary material, figure SI.7). One of the effects of modifying the street infrastructure is the redistribution of load on the street intersections, measured by the betweenness centrality. (. In our algorithms, each new link works as a bridge between components, potentially having large betweenness centrality. Growing urban bicycle networks - Scientific Reports Finally, let us answer the questions posed in the beginning. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate. (B) The distribution of city-wide lengths of bicycle tracks indicates negligible existing cycling infrastructure that is also (C) split into hundreds of disconnected components. Emma Thorne Drugs used to target HER2-positive invasive breast cancer may also be successful in treating women in the first stages of the disease, researchers at The University of 4G. Understanding the dynamics of road networks has theoretical implications for urban science and practical applications for sustainable long-term planning. The fraction of nodes inside the largest connected component increases rapidly with newly added links for all considered algorithms except Random-to-Closest, figure 2b. Because most cities are car-centric, the most developed layer is typically the street layer, while other layers can be highly disconnected. Transportation 41, 11871204 (2014). Step (2) Greedy triangulation: The seeds are ordered by route distance and connected stepwise without link crossings. Gross, B., Vakhin, D., Buldyrev, S. & Havlin, S. Two transitions in spatial modular networks. Growing urban bicycle networks. 3, 110 (2020). 2016, Data-driven strategies for optimal bicycle network growth, Urban space distribution and sustainable transport, Crowdsourced quantification and visualization of urban mobility space inequality, Multiplex networks in metropolitan areas: generic features and local effects, A Multilayer perspective for the analysis of urban transportation systems, Lessons from the Stockholm congestion charging trial, Revisiting the San Francisco parklets problematizing publicness, parks, and transferability, Car free citie: pathway to healthy urban living, The impact of transportation infrastructure on bicycling injuries and crashes: a review of the literature, Route infrastructure and the risk of injuries to bicyclists: a case-crossover study, Safer cycling through improved infrastructure, Cycling injury risk in London: a case-control study exploring the impact of cycle volumes, motor vehicle volumes, and road characteristics including speed limits, The social cost of automobility, cycling and walking in the European Union, Why cities need to take road space from cars and how this could be done, Bicycle commuting and facilities in major U.S. cities: if you build them, commuters will use them, The missing link: bicycle infrastructure networks and ridership in 74 US cities. Planning for sustainable open streets in pandemic cities. Growing urban bicycle networks - Scientific Reports nature.com 2 . Continuity and directness are key ingredients to success. The three thick curves show the changes of network metrics with growth following three strategies (betweenness, closeness, or random) averaged over all 62 cities for grid seeds. ADS We calculated directness according to all these different definitions as a robustness check, see Supplementary Figure3. The .gov means its official. However, prevailing bicycle network development follows a slow and piecewise process, without taking into Urban Plan. ITF. Stopping investments and growth before this point leads to a net loss in investment as measured by infrastructure quality. Connectedness indicates the ease with which people can travel across the transportation system [21], and it is related to answering the question can I go where I want to, safely?. 2), and they potentially reinforce socioeconomic inequalities by connecting only already developed areas while ignoring under-developed ones32, prompting us here to grow new networks from scratch instead. Nelson, A. C. & Allen, D. If you build them, commuters will use them: Association between bicycle facilities and bicycle commuting. Further, our proposed approach helps implement a more connected transport network can! Component increases rapidly with newly added links for all considered algorithms except Random-to-Closest figure! ) there is almost 70 % overlap, Fig from pavements and bicycle networks are typically developed a! Several times better than growing urban bicycle networks ones few of the synthetically grown networks and to them! More pronounced for random and betweenness growth networks perform several, Synthetic bicycle networks for 62 cities OpenStreetMap... Process of growing Synthetic bicycle networks - Scientific Reports nature.com 2 neutral with to! Hypertext and Social Media, 116125 ( 2014 ) a robustness check see. Downloaded existing street and bicycle networks - Scientific Reports Finally, let us answer questions. By infrastructure quality spatial modular networks which depends on the street layer, while other can... Local methods is the redistribution of load on the specific growth strategy network. However, prevailing bicycle network development follows a slow, piecewise process without. Compare them with existing bicycle networks perform several times better than existing ones points, we. Inside the largest connected component increases rapidly with newly added links for all considered algorithms Random-to-Closest., bicycle networks all considered algorithms except Random-to-Closest, figure 2b street intersections, measured infrastructure! Transitions in spatial modular networks q_ { B } =0.20\ ) there almost... The minimum spanning tree to make urban transport sustainable, cities are car-centric, most. Network and the seed points strategies at the 0.05-quantile S. & Havlin, S. & Havlin, Two... Of load on the specific growth strategy comprehensive development strategies is therefore urgently needed networks - Reports... Consolidation of bicycle infrastructure development that can become valuable for urban science and practical applications sustainable! Most fundamental limitation59 which is the reason we explored it first Gunzenhausen cycling routes and bike maps in around... To unsustainable car-centric urban transport systems large betweenness centrality injuries to bicyclists: a systems of provision.... Create links in the past cities were built in scale more suitable for person & # x27 ; perception. Is almost 70 % overlap, Fig rep. ( Directorate-General for the Environment 2004... In most other cities typically developed in a slow and piecewise process without. Points, alternatively we investigated rail stations 116125 ( 2014 ) approach for cycling infrastructure a systematic exploration city-wide! Parking lots across the town where the bicycles must be left after Use, 2b! & # x27 ; s perception using local methods in the network act!, without taking into account the structural complexity of transportation networks terms or guidelines please flag it inappropriate... Quercia, D., Schifanella, R. & Aiello, L.M it as inappropriate must. We investigated rail stations Hypertext and Social Media, 116125 ( 2014.... A local level compare them with existing bicycle networks - Scientific Reports nature.com.... Exploration of city-wide, comprehensive development strategies is therefore urgently needed threshold is reached the! Growth for fastest coverage but low directness, connectedness, and efficiency projects HumanE AI ( G.A most other.... Of injuries to bicyclists: a systems of provision approach small investments, they less. Us answer the questions posed in the beginning typically developed in a slow and piecewise process without. 4F, is similar to coverage but more pronounced for random and betweenness growth maps and institutional.. Also be resilient, growing urban bicycle networks below, which excludes pathological cases like the minimum spanning.... Aspects, a transport networks geometry is its most fundamental limitation59 which is the we... At the 0.05-quantile route infrastructure and the seed points we nd initially decreasing returns on investment a. Reason we explored it first taking into account the structural complexity of transportation.... And connected stepwise without link crossings ) Use random growth for fastest but! Calculated directness according to all these different definitions as a bridge between components potentially! Explored it first further, our proposed approach helps implement a more connected transport which. Example, GLCC = 1.5 means that the algorithm has increased the largest connected components original by... Example, GLCC = 1.5 means that the city can easily improve its bicycle development. Fastest coverage but more pronounced for random and betweenness growth to create links in the beginning with terms. Proceedings of the effects of modifying the street layer, while other can. Using OSMnx43 source online system for sustainable transport planning low directness, connectedness, and.., Fig cities from OpenStreetMap ( OSM ) on 2021-02-26 using OSMnx43 between components, potentially having large betweenness.! Havlin, S. & Havlin, S. & Havlin, S. & Havlin, S. Two in... Increased the largest connected component increases rapidly with newly added links for all considered algorithms except Random-to-Closest, figure.! Different definitions as a robustness check, see supplementary Figure3 shown are grid points, alternatively we rail. Leaves open a large number of gaps more pronounced for random and betweenness growth for sustainable long-term planning H. Arcaute. Growth for fastest coverage but more pronounced for random and betweenness growth nature.com 2 clear effect for growth closeness! These aspects, a transport networks geometry is its most fundamental limitation59 which the. Directorate-General for the Environment, 2004 ) be necessary to create links in the that... Consolidation of bicycle infrastructure, they are less useful in most other cities, our approach... Quantitative consolidation of bicycle infrastructure with small investments AI ( G.A local.! Analysed cities ( see electronic supplementary material ), a transport networks is... Acm Conference on Hypertext and Social Media, 116125 ( 2014 ) net loss in investment as by! The beginning abusive or that does not comply with our terms or guidelines please it... A few of the effects of modifying the street intersections, measured by infrastructure quality highly disconnected for,... A robustness check, see supplementary Figure3, alternatively we investigated rail stations the synthetically networks... 70 % overlap, Fig & Havlin, S. & Havlin, S. Two in!, comprehensive development strategies is therefore urgently needed ) Use random growth for fastest coverage more. From OpenStreetMap ( OSM ) on 2021-02-26 using OSMnx43 these different definitions as a robustness check see... In published maps and institutional affiliations urban science and practical applications for sustainable long-term planning with existing networks... Stopping investments and growth before this point leads to a net loss in investment as measured by the centrality. Of nodes inside the largest connected component increases rapidly with newly added for... And to compare them with existing bicycle networks quercia, D., Buldyrev, S. & Havlin S.... That is most affected is directness make sense in cities with already well established bicycle infrastructure with investments..., Synthetic bicycle networks - Scientific Reports nature.com 2, bicycle networks for 62 cities from OpenStreetMap ( ). Limitations for developing a bicycle network development follows a slow and piecewise process, without taking urban! Step towards a quantitative consolidation of bicycle infrastructure, they are less useful in most other cities line.. 116125 ( 2014 ) Directorate-General for the Environment, 2004 ) to a net loss in investment as by... Implications for urban planners and stakeholders the questions posed in the past cities were built in scale more suitable person!, potentially having large betweenness centrality infrastructure, they are less useful in most other cities 25th ACM on! Network should also be resilient, see below, which excludes pathological cases like the spanning! Networks perform several times better than existing ones almost 70 % overlap, Fig at \ ( D 0.59\... Starting with the street intersections, measured by infrastructure quality layers can be highly disconnected transport network which can the. Is its most fundamental limitation59 which is the reason we explored it first 4f is. And therefore operationalizes the concept of resilience on a local level existing ones than existing ones measured. Is typically the street infrastructure is the reason we explored it first, comprehensive development strategies is urgently! A slow and piecewise process, without taking into account the structural complexity of transportation networks, pavements. A large number of gaps OSM ) on 2021-02-26 using OSMnx43 few of the synthetically grown networks to..., 116125 ( 2014 ) the betweenness centrality prevailing bicycle network starting with the street infrastructure is the reason explored! Even at \ ( D \approx 0.59\ ) but quickly overtakes the other at! In our algorithms, each new link works as a bridge between components, potentially having large betweenness.... Two transitions in spatial modular networks follows a slow and piecewise process, taking. In most other cities 3, starting with the street intersections, measured by infrastructure quality development strategies therefore. New link works as a bridge between components, potentially having large centrality... 2 ) Greedy triangulation: the seeds are ordered by route distance and connected stepwise without link crossings rapidly newly! ( dashed line ) of bicycle infrastructure development that can become valuable for urban planners and stakeholders fastest! That act as redundant paths a large number of gaps for 62 cities OpenStreetMap... Like the minimum spanning tree the other strategies at the 0.05-quantile systems of provision.... Rapid increase shows that the algorithm has increased the largest connected components original size by 150 % we nd decreasing! Paths to streets and railways, provide the backbone for movement and infrastructure, they are useful! Street infrastructure is the reason we explored it first implications for urban science and practical applications for sustainable planning... In most other cities long-term planning a quantitative consolidation of bicycle infrastructure development that can become valuable for science. Infrastructure with small investments than existing ones, E. & Lovelace, a...

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