Origin, Development, and Synaptogenesis of Cortical Interneurons

The mammalian cerebral cortex represents one of the most recent and astonishing inventions of nature, responsible of a large diversity of functions that range from sensory processing to high-order cognitive abilities, such as logical reasoning or language. Decades of dedicated study have contributed to our current understanding of this structure, both at structural and functional levels. A key feature of the neocortex is its outstanding richness in cell diversity, composed by multiple types of long-range projecting neurons and locally connecting interneurons. In this review, we will describe the great diversity of interneurons that constitute local neocortical circuits and summarize the mechanisms underlying their development and their assembly into functional networks.This study was supported by the Spanish Ministerio de Ciencia e Innovación (PID2020-113086RB-I00 and RYC2018-025215-I) to RD. AL was funded by the Alfonso Martín Escudero Foundation

On horizontal cooperation in linear production processes with a supplier that controls a limited resource

In this paper we consider a two-echelon supply chain with one supplier that controls a limited resource and a finite set of manufacturers who need to purchase this resource. We analyze the effect of the limited resource on the horizontal cooperation of manufacturers. To this end, we use cooperative game theory and the existence of stable distributions of the total profit among the manufacturers as a measure of the possibilities of cooperation. The game theoretical model that describes the horizontal cooperation involves externalities, which arise because of the possible scarcity of the limited resource and the possible coalition structures that can be formed. Furthermore, manufacturers do not know how the supplier will allocate the limited resource, therefore, how much of this resource they will obtain is uncertain for all concerned. Nevertheless, when the limited resource is not scarce for the grand coalition, the existence of stable distributions of the total profit is guaranteed and consequently the collaboration among the manufacturers is profitable for them all. In the event that the limited resource is insufficient for the grand coalition, we introduce a new cooperative game that assesses the expectations of each coalition of manufacturers regarding the amount of the limited resource they can obtain. We analyze two extreme expectations: the optimistic and the pessimistic. In the optimistic case, we cannot reach a conclusion regarding the full cooperation of the manufacturers. In the pessimistic case, with one reasonable assumption, the existence of stable distributions of the total profit is guaranteed and as a result the collaboration among manufacturers is a win–win deal.Ministerio de Economía y Competitividad | Ref. MTM2014-54199-PMinisterio de Economía y Competitividad | Ref. MTM2014-53395-C3-3-PFundación Séneca | Ref. 19320/PI/1

Effect of width and boundary conditions on meeting maneuvers on two-way separated cycle tracks

Cycle track design guidelines are rarely based on scientific studies. In the case of off-road two-way cycle tracks, a minimum width must facilitate both passing and meeting maneuvers, being meeting maneuvers the most frequent. This study developed a methodology to observe meeting maneuvers using an instrumented bicycle, equipped with video cameras, a GPS tracker, laser rangefinders and speed sensors. This bicycle collected data on six two-way cycle tracks ranging 13-2.15 m width delimitated by different boundary conditions. The meeting maneuvers between the instrumented bicycle and every oncoming bicycle were characterized by the meeting clearance between the two bicycles, the speed of opposing bicycle and the reaction of the opposing rider: change in trajectory, stop pedaling or braking. The results showed that meeting clearance increased with the cycle track width and decreased if the cycle track had lateral obstacles, especially if they were higher than the bicycle handlebar. The speed of opposing bicycle shown the same tendency, although were more disperse. Opposing cyclists performed more reaction maneuvers on narrower cycle tracks and on cycle tracks with lateral obstacles to the handlebar height. Conclusions suggested avoiding cycle tracks narrower than 1.6 m, as they present lower meeting clearances, lower bicycle speeds and frequent reaction maneuvers. (C) 2015 Elsevier Ltd. All rights reserved.García García, A.; Agustin Gomez, F.; Llorca Garcia, C.; Angel-Domenech, A. (2015). Effect of width and boundary conditions on meeting maneuvers on two-way separated cycle tracks. Accident Analysis and Prevention. 78:127-137. doi:10.1016/j.aap.2015.02.019S1271377

Motor vehicles overtaking cyclists on two-lane rural roads: Analysis on speed and lateral clearance

Two-lane rural roads in Spain accommodate significant bicycle traffic volumes, mainly associated to sport and leisure activities. Motor vehicles' higher speed, weight and volume, compared to cyclists, represent a serious safety concern when overtaking a bicycle. Spanish traffic rules determine a minimum 1.5. m lateral distance.This research characterised 2928 overtaking manoeuvres in the overtaking lateral clearance between motor vehicle and bicycle, as well as in the motor vehicle speed, in contrast with previous research. Two instrumented bicycles were equipped with laser rangefinders, a GPS tracker and three video cameras. They rode along seven rural road segments at a speed between 15 and 25. km/h, centred on the paved shoulder, or as close as possible to the outer edge. Besides, this methodology allowed the characterisation of the overtaken vehicle type, its left lane occupation as well as its interaction with opposing traffic flow. For each session, rider's general risk perception was also registered.The analysis suggested that lateral clearance is not the only factor that influenced rider's risk perception, although current standards are only related to it. On the contrary, a combined factor of lateral clearance, vehicle type and vehicle speed had a more significant correlation with the perceived risk. This agreed with literature models of transient aerodynamic forces between overtaking and overtaken vehicles. Results showed that effect of heavy vehicles on bicyclists was also strong. In addition to this, the combined factor of clearance and speed was higher on tangent sections where overtaking was permitted.Llorca Garcia, C.; Ángel-Domènech, A.; Agustin Gomez, F.; García García, A. (2017). Motor vehicles overtaking cyclists on two-lane rural roads: Analysis on speed and lateral clearance. Safety Science. 92:302-310. doi:10.1016/j.ssci.2015.11.005S3023109

Development of a new microscopic passing maneuver model for two-lane rural roads

Microsimulation is a useful tool to analyze traffic operation. On two-lane highways, the complexity of passing and the interaction with oncoming traffic requires specific models. This study focused on the development of a passing desire, decision and execution model. Results of the observation of 1752 maneuvers on 10 rural roads in Spain were used for this development. The model incorporated the effect of new factors such as available sight distance, delay and remaining travel time until the end of the highway segment. Outputs of the model were compared to observed data: firstly, individual passing maneuvers; secondly, traffic flow, percent followers and number of passing maneuvers in four single passing zones with two different traffic levels. The model was validated in four alternative passing zonesData collection was part of the research project "Desarrollo de modelos de distancias de visibilidad de adelantamiento", funded by the Spanish Ministry of Economy and Competitiveness, with reference number TRA2010-21736. Authors wish to thank Spanish General Directorate of Traffic, Spanish Ministry of Public Works, Valencia Regional Department of Transport and Valencia Province Road Department, for their collaboration in the field study.Llorca Garcia, C.; Moreno Chou, AT.; Lenorzer, A.; Casas, J.; García García, A. (2015). Development of a new microscopic passing maneuver model for two-lane rural roads. Transportation Research Part C: Emerging Technologies. 52:157-172. doi:10.1016/j.trc.2014.06.001S1571725

Operational effectiveness of passing zones depending on their length and traffic volume

Most studies on two-lane highway operations have focused on the percentage of following vehicles or the adjustment of the Highway Capacity Manual (HCM) procedure to local data. The HCM proposes the length of no-passing zones as a model parameter; however, the distribution and characteristics of passing zones are not addressed. In fact, only a few studies on the expected number of passes in a passing zone have been carried out. This research presents an analysis of the effectiveness of passing zones in terms of their length and traffic volume. Data were collected from four passing zones on a rural highway in Spain. The two-way traffic volumes ranged from 100 to 900 vehicles per hour (vph), and the passing zone lengths ranged from 265 to 1,270 m. More than 1,600 passing maneuvers were recorded. The operational effectiveness of the passing zones was obtained from the passing frequency and the passing rate. The results indicated that the longer the passing zone, the higher the passing frequency; however, the results stabilized with lengths above 1,100 m. Balanced flows with two-way traffic volumes between 600 and 700 vph optimized the number of passes. Nevertheless, the increase in the passing frequency with the traffic volume was lower than with the increase in following vehicles. The results were validated with data from another 12 passing zones. Finally, HCM adjustments based on the percentage of no-passing zones did not reliably represent the effectiveness of passing zones. Therefore, the effectiveness of every passing zone should be considered, and adjustment factors should be modified to maximize the passing opportunities for traffic volumes between 600 and 700 vph.The authors thank the Spanish Ministry of Science and Innovation, which subsidized the research project, and the Spanish Ministry of Public Works for its collaboration during the field study.Moreno Chou, AT.; Llorca Garcia, C.; García García, A.; Pérez Zuriaga, AM. (2013). Operational effectiveness of passing zones depending on their length and traffic volume. Transportation Research Record. (2395):57-65. doi:10.3141/2395-07S57652395Romana, M. G. (1999). Passing Activity on Two-Lane Highways in Spain. Transportation Research Record: Journal of the Transportation Research Board, 1678(1), 90-95. doi:10.3141/1678-12Al-Kaisy, A., & Freedman, Z. (2010). Estimating Performance on Two-Lane Highways. Transportation Research Record: Journal of the Transportation Research Board, 2173(1), 72-79. doi:10.3141/2173-09Al-Kaisy, A., & Karjala, S. (2010). Car-Following Interaction and the Definition of Free-Moving Vehicles on Two-Lane Rural Highways. Journal of Transportation Engineering, 136(10), 925-931. doi:10.1061/(asce)te.1943-5436.0000148Al-Kaisy, A., & Durbin, C. (2011). Platooning on Two-lane Two-way Highways: An Empirical Investigation. Procedia - Social and Behavioral Sciences, 16, 329-339. doi:10.1016/j.sbspro.2011.04.454Gattis, J. L., Alguire, M. S., Townsend, K., & Rao, S. (1997). Rural Two-Lane Passing Headways and Platooning. Transportation Research Record: Journal of the Transportation Research Board, 1579(1), 27-34. doi:10.3141/1579-04Dixon, M. P., Sarepali, S. S. K., & Young, K. A. (2002). Field Evaluation of Highway Capacity Manual 2000 Analysis Procedures for Two-Lane Highways. Transportation Research Record: Journal of the Transportation Research Board, 1802(1), 125-132. doi:10.3141/1802-15Polus, A., & Cohen, M. (2009). Theoretical and Empirical Relationships for the Quality of Flow and for a New Level of Service on Two-Lane Highways. Journal of Transportation Engineering, 135(6), 380-385. doi:10.1061/(asce)0733-947x(2009)135:6(380)Rozenshtein, S., Polus, A., & Cohen, M. (2012). Models for Estimating Drivers following on Two-Lane Rural Highways. Transportation Research Record: Journal of the Transportation Research Board, 2286(1), 68-75. doi:10.3141/2286-08Al-Kaisy, A., & Durbin, C. (2008). Evaluating new methodologies for estimating performance on two-lane highways. Canadian Journal of Civil Engineering, 35(8), 777-785. doi:10.1139/l08-020Llorca, C., & García, A. (2011). Evaluation of Passing Process on Two-Lane Rural Highways in Spain with New Methodology Based on Video Data. Transportation Research Record: Journal of the Transportation Research Board, 2262(1), 42-51. doi:10.3141/2262-0

Daytime and Nighttime Passing Maneuvers on a Two-Lane Rural Road in Spain

[EN] Passing is one of the most complex driving maneuvers performed on two-lane rural roads and has important effects on road safety and traffic operation. Passing is affected by driving behavior, road geometry, traffic volume, and traffic composition as well as external factors. Research was developed to compare the passing process under daytime and nighttime conditions. An experimental method was designed to collect video data of passing maneuvers on a two-lane rural road segment located near Valencia, Spain. Two methods were used: (a) external observations of four passing zones with six video cameras and (b) an instrumented vehicle equipped with video cameras and laser rangefinders, driven slightly below the operating speed along a segment of the same road so it would be passed by other vehicles. A total of 291 maneuvers were observed, up to 20% of which were at night. Macroscopic analysis results indicated that approximately 17% of passes were at night, even though passing frequency and passing demand decreased at night. Also, the behaviors of individual drivers who passed other vehicles were different at night and during the day. Maneuvers limited by the presence of an opposing vehicle were performed more quickly at night, even if the accepted gaps were longer. In this case, a more difficult perception of distances to opposing vehicles and of vehicle speeds explained the differences. In contrast, maneuvers limited by sight distance (without a visible opposing vehicle) were slower at night. This observation matched a traditional hypothesis: passing at night is safer because the headlights of an opposing vehicle allow a driver to anticipate the vehicle's position before it becomes visible.The authors thank the Spanish Ministry of Economy and Competitiveness for subsidizing the research project as well as the Spanish Ministry of Public Works and the Spanish General Traffic Directorate for collaboration during the field study.Llorca Garcia, C.; Moreno Chou, AT.; García García, A.; Pérez Zuriaga, AM. (2013). Daytime and Nighttime Passing Maneuvers on a Two-Lane Rural Road in Spain. Transportation Research Record. (2358):3-11. doi:10.3141/2358-01S311235

Operational Considerations of Passing Zones for Two-lane Highways: Spanish Case Study

[EN] The U.S. Highway Capacity Manual (HCM 2010) methodology is used in Spain to evaluate traffic operation and quality of service. In two-lane undivided highways, the effect of limiting where drivers could pass slower vehicles, or passing restrictions, is considered through the percentage of no-passing zones. This measure does not account for how passing opportunities are distributed along the road. The objective of this research was to evaluate the effect percentage of no-passing zones and average passing zone length on two-lane, and incorporate them in the analysis methodology, if significant. The TWOPAS microsimulation program was calibrated and validated to the Spanish conditions. Passing restrictions had little effect on average traffic speed (ATS), with differences lower than 6 km/h between a segment of road with no passing restrictions and a segment of a road with 100% of length with passing restriction. Conversely, passing restrictions can increase percent time spent following (PTSF) up to 30%. Increasing the passing zone length beyond 2,000 m does not improve PTSF. The new models could be used to better estimate traffic operation on Spanish two-lane highways.The research was funded by the Spanish Ministry of Economy and Competitiveness [TRA2013-42578-P], and has been partially developed as a result of a mobility stay at the University of Florida funded by the Spanish Ministry of Economy and Competitiveness [EEBB-I-15-09970]. The research was completed with the support of the FPI Research and Teaching Fellowship of the Spanish Ministry of Economy and Competitiveness [BES-2011-044612] and the TUM University Foundation Fellowship (TUFF) for international postdocs. We would like to thank Dr. Lemke from the Bundesanstalt fur Strassenwesen (Federal Highway Research Institute) for providing the final report of the research project FE 16.0015/2009 (23). This work was supported by the German Research Foundation (DFG) and the Technical University of Munich (TUM) in the framework of the Open Access Publishing Program.Moreno Chou, AT.; Llorca Garcia, C.; Washburn, S.; Bessa Jr., JE.; García García, A. (2018). Operational Considerations of Passing Zones for Two-lane Highways: Spanish Case Study. PROMET - Traffic&Transportation. 30(5):601-612. https://doi.org/10.7307/ptt.v30i5.2776S60161230

Seguridad De Ciclistas Circulando En Pelotón En Carretera Convencional

[ES] La afluencia de ciclistas aficionados en carreteras convencionales para la práctica de actividades deportivas es muy notable, llegando en algunos casos a que la intensidad de tráfico ciclista supere a la de tráfico motorizado. Sin embargo, la presencia de ciclistas compartiendo la infraestructura con vehículos supone un problema para la seguridad vial. Los accidentes relacionados con alcances, adelantamientos o salidas de vía tienen consecuencias muy graves, debido a la diferencia de velocidad y tamaño entre bicicletas y vehículos y a la falta de protección del cuerpo del ciclista ante un accidente.En particular, la disposición de los ciclistas al circular en la vía (individualmente, en línea, en paralelo, etc.) puede afectar a su visibilidad, capacidad de reacción y margen de seguridad disponible en las maniobras de adelantamiento realizadas por el tráfico motorizado. Esta investigación caracterizó las trayectorias y la posible invasión del sentido contrario de los vehículos a motor, cuando adelantaron a ciclistas dispuestos en diversas configuraciones de pelotón (individual, 2 en línea, 2 en paralelo).Para ello, se hizo circular a tres ciclistas, en configuraciones previamente fijadas, por un tramo de carretera convencional. Las bicicletas fueron equipadas con distanciómetros láser, medidores de velocidad, GPS cámaras de video, y un pulsador mediante el que los ciclistas valoraban el riesgo percibido cada vez que un vehículo motorizado les rebasaba. El análisis de los datos obtenidos permitió comparar, en las diversas configuraciones de pelotón, la distribución de las distancias laterales durante el adelantamiento, las velocidades de los vehículos que adelantan, y el nivel de riesgo percibido.Los resultados obtenidos proporcionaron criterios para evaluar los riesgos de circular en cada una de las configuraciones, en base a características objetivas (separación, velocidad o tipo de vehículo), y subjetivas (percepción de riesgo).Este estudio se enmarca en el proyecto “CASEFU, Estudio experimental de la funcionalidad y seguridad de las carreteras convencionales” con referencia TRA2013-42578-P, subvencionado por el Ministerio de Economía y Competitividad.Llorca García, C.; Serra Planelles, J.; García García, A. (2016). Seguridad De Ciclistas Circulando En Pelotón En Carretera Convencional. En XII Congreso de ingeniería del transporte. 7, 8 y 9 de Junio, Valencia (España). Editorial Universitat Politècnica de València. 1709-1717. https://doi.org/10.4995/CIT2016.2016.4061OCS1709171

Operational Considerations of Passing Zones for Two-lane Highways: Spanish Case Study

The U.S. Highway Capacity Manual (HCM 2010) methodology is used in Spain to evaluate traffic operation and quality of service. In two-lane undivided highways, the effect of limiting where drivers could pass slower vehicles, or passing restrictions, is considered through the percentage of no-passing zones. This measure does not account for how passing opportunities are distributed along the road. The objective of this research was to evaluate the effect percentage of no-passing zones and average passing zone length on a two-lane highway and, if significant, incorporate them in the analysis methodology,. The TWOPAS microsimulation program was calibrated and validated to the Spanish conditions. Passing restrictions had little effect on average traffic speed (ATS), with differences lower than 6 km/h between a road segment with no passing restrictions and a road segment with a passing restriction on 100% of its length. Conversely, passing restrictions can increase the percent time spent following (PTSF) up to 30%. Increasing the passing zone length beyond 2,000 m does not improve PTSF. The new models could be used to better estimate traffic operation on Spanish two-lane highways. Document type: Articl