Transport System Research Articles

Urban Air Mobility (UAM) in Türkiye: Evaluating Existing Aviation Laws and International Practices

Urban Air Mobility (UAM) has emerged as a solution to transport challenges such as traffic congestion, environmental impacts, and lack of adequate public transport systems in urban areas. As the interest in UAM objects such as electric vertical take-off and landing aircraft (eVTOL) is increasing, it is important to understand whether the current regulations are sufficient to address the sui generis difficulties of this brand new technology. This article examines the adequacy of Türkiye's current legal framework to ensure the safe, effective, and sustainable integration of UAM. This article analyses Türkiye's existing aviation legislation, in particular the Turkish Civil Aviation Law and the instructions issued by the Directorate General of Civil Aviation (DGCA) and examines their applicability to UAM. The article discusses various regulatory gaps such as the lack of standards specifically designed for UAM, inadequate safety, environmental and operational regulations, and unclear guidelines on airspace integration. The article also discusses various UAM regulations prepared by the International Civil Aviation Organisation (ICAO), the European Union Aviation Safety Agency (EASA), and the approaches of pioneer countries in this area, such as the US, Germany, and Japan. Through a comparative analysis, it demonstrates the key lessons learnt from these international practices and presents suggestions for improving Türkiye's regulatory environment. The study emphasises the need for targeted reforms, introduction of specific standards, and a new regulative framework to foster the successful integration of UAM. The findings aim to contribute to the establishment of a solid legal framework to ensure that Türkiye is prepared for the future of UAM.

Evaluation of Travel Time Performance of Multimodal Transport System of Bhopal City

Evaluation of Travel Time Performance of Multimodal Transport System of Bhopal City

Antagonistic Effect of Microplastic Polyvinyl Chloride and Nitrification Inhibitor on Soil Nitrous Oxide Emission: An Overlooked Risk of Microplastic to the Agrochemical Effectiveness.

Microplastics are widely persistent in agricultural ecosystems and may affect soil nitrous oxide (N2O) emissions. Nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) is applied to decelerate nitrification and reduce soil N2O emission. Nevertheless, the interactive effects of nitrification inhibitors and microplastics on soil N2O emissions have not been investigated. Sole DMPP, polyvinyl chloride (PVC), and polystyrene (PS) substantially reduced agricultural soil N2O emission rates by 25.93%, 69.04%, and 73.89%, respectively. Nevertheless, PVC and DMPP had antagonistic effects on the N2O emission rates. The observed reductions in N2O emissions could be attributed to variations in soil oxygen availability, electron transport system activities, and Firmicutes, nap, and GDH genes. Moreover, the DMPP, PVC, and PS alone or copresences significantly enhanced the soil ecosystem multifunctionality (EMF). The findings shed light on the role of microplastics in soil N2O emission, EMF, and the microbial community, expanding the understanding of microplastics' effects on agrochemical effectiveness.

Stuck in the driver’s seat: a conceptualisation for understanding car dependence and its determinants

ABSTRACT Car dependence brings along many negative social and environmental externalities that policymakers and stakeholders need to consider. Nonetheless, the concept is not well defined and lacks a clear framework regarding its determinants and mechanisms, which also leads to problems in terms of its operationalisation. Therefore, this paper proposes a conceptualisation and operationalisation of car dependence, which can serve as a basis for further research and policy. We define car dependence as the extent to which an individual is incapable to participate in location-based activities without a car in a satisfactory way. This definition is based on the theoretical background of the capabilities approach and the concept of motility and also linked to the concept of accessibility. Our conceptual model consists of seven components, most of which have been considered separately in previous conceptualisations, namely the land use system, transport system, natural environment, temporal component, social environment, and individual objective/subjective characteristics. These components range from being external to the individual (e.g. the land use system) to internal (e.g. individual features). Considering these components jointly emphasises the importance of looking at car dependence in a holistic, unifying way. This approach contributes to a better understanding of car dependence that goes beyond the explicit analysis of components in previous research. In addition, we provide a systematic approach to operationalising car dependence that contributes to a more comparable approach to measuring car dependence. Researchers have to decide whether they want to examine car dependence via its components or via self-report by individuals, whether they want to study the full set of components or only a subset, and whether they want to consider perceptions or factual information about external components. Therefore, our conceptualisation and operationalisation provide valuable new insights into car dependence regarding new research directions and policy approaches.

Exploring the switch to urban train services: The impact of perceived accessibility and its moderating effects

Perceived accessibility refers to individuals’ subjective perception of how easy it is to reach destinations using a specific mode of transport. As such, understanding the effect of perceived accessibility on travel behavior is essential for creating transport systems and urban environments that are efficient, equitable, and sustainable. This study develops a new integrated model by combining the Norm Activation Model (NAM), the Theory of Planned Behavior (TPB), perceived risk, and perceived accessibility. This enhanced model offers a comprehensive understanding of the factors influencing individuals’ intentions to switch to urban train systems. Additionally, the moderating effects of perceived accessibility on the link between personal, contextual factors and switching intention are also explored. The model developed is tested using data obtained from a sample of 535 individuals in Hanoi, Vietnam. This is particularly important because more research in low- and middle-income countries (LMICs) is needed to address the sustainability challenges these nations face due to their dependency on motorized private transport. The findings show that subjective norms have the strongest effect on the intention, followed by personal norms, attitude, and perceived accessibility. This study also confirms the moderating role of perceived accessibility on the link between attitude and switching intention, while the other hypotheses regarding the moderating effects of perceived accessibility are not supported by the findings. These insights aim to inform policymakers and public transport authorities in developing targeted strategies to promote sustainable urban mobility in Vietnam.

Enhancing Vaccine Efficacy and Accessibility through Microneedle Technology: A Review

Microneedling, a minimally invasive technique involving the creation of microchannels in the skin, has emerged as a promising platform for vaccine delivery. The use of microneedles for vaccination represents a new era in immunization techniques, wherein patients no longer dread sharp pricks. Their breakthrough potential lies in their ability to deliver vaccines directly into the epidermis or dermis where a high density of immune cells improve the particularly relevant effects of vaccines. Their intro- duction has met various challenges often experienced with traditional methods like bites caused by fear, pain from needles, or even that any medical doctor may take a long to administer them. Microneedles could improve stability and lessen the dependence on cold chain transport systems since they can be prepared in dry form. In addition to providing an al- ternative to syringes, they are also considered less painful than them. The review highlights the potential of mi- croneedles to improve vaccination rates, especially in un- derserved populations, and identifies key areas for future research and development.

Molecular Structure of the Na+,K+-ATPase α4β1 Isoform in Its Ouabain-Bound Conformation.

Na+,K+-ATPase is the active ion transport system that maintains the electrochemical gradients for Na+ and K+ across the plasma membrane of most animal cells. Na+,K+-ATPase is constituted by the association of two major subunits, a catalytic α and a glycosylated β subunit, both of which exist as different isoforms (in mammals known as α1, α2, α3, α4, β1, β2 and β3). Na+,K+-ATPase α and β isoforms assemble in different combinations to produce various isozymes with tissue specific expression and distinct biochemical properties. Na+,K+-ATPase α4β1 is only found in male germ cells of the testis and is mainly expressed in the sperm flagellum, where it plays a critical role in sperm motility and male fertility. Here, we report the molecular structure of Na+,K+-ATPase α4β1 at 2.37 Å resolution in the ouabain-bound state and in the presence of beryllium fluoride. Overall, Na+,K+-ATPase α4 structure exhibits the basic major domains of a P-Type ATPase, resembling Na+,K+-ATPase α1, but has differences specific to its distinct sequence. Dissimilarities include the site where the inhibitor ouabain binds. Molecular simulations indicate that glycosphingolipids can bind to a putative glycosphingolipid binding site, which could potentially modulate Na+,K+-ATPase α4 activity. This is the first experimental evidence for the structure of Na+,K+-ATPase α4β1. These data provide a template that will aid in better understanding the function Na+,K+-ATPase α4β1 and will be important for the design and development of compounds that can modulate Na+,K+-ATPase α4 activity for the purpose of improving male fertility or to achieve male contraception.

Liposomes – metabolically active drug transport systems: visualization and pharmacokinetic. Part 2 (review)

Introduction. In the second part of the review we discussed aspects of visualization, pharmacokinetics and biodistribution of liposomes.Text. Many different methodsh as been proposed for the visualization of liposoms morphology and quality such as light microscopy, ESEM, TEM, AFM, etc. Each method have own advantages and limitations which are discussed in the article: In general, the selection of method depends on the specific morphological characteristics and level of details. It is important to understand the specificity of the liposomes and the visualization method for correct preparation of samples. Adequately performed pharmacokinetic and biodistribution studies can also be used as a tool for liposome visualization. The nature of active pharmaceutical ingredients, dose, lipid components, size of liposomes, charge, coating of liposomes with excipients and route of administration significantly affects the pharmacokinetics of liposomal forms. Additionally, the interaction of liposomal forms with the immune system, reticuloendothelial system and blood components play an important role in their absorption, distribution and elimination.Conclusion. The better understanding of the absorption, biodistribution, metabolism and clearance of liposomal formulations is essential for the development of modern drugs.

The role of international cooperation in improving road traffic safety

The article is devoted to a detailed analysis of the impact of international cooperation on improving road traffic safety in Ukraine. The author emphasizes that every year, approximately 1.3 million people die worldwide as a result of road traffic accidents, with tens of millions more suffering injuries of varying severity. This makes the issue one of the most pressing on the international agenda. In this regard, international cooperation in the field of road traffic safety is of paramount importance. One of the main topics of the article is the analysis of international agreements, such as the 1968 Vienna Convention on Road Traffic, which is a key document in regulating road traffic at the international level. The Convention establishes uniform standards for the participating countries, promoting the unification of traffic rules, which is especially important in the context of the globalization of transport systems. The article examines how Ukraine is gradually implementing the provisions of this Convention into its national legislation, which is an important step toward harmonization with international standards. The article also explores global initiatives such as «Vision Zero,» which aims to achieve zero road deaths. This initiative originated in Sweden and has spread to many countries in Europe and around the world. The article analyzes successful cases of this initiative’s implementation in EU countries, which have significantly reduced road mortality rates. Ukraine is also striving to adapt these standards, which could become a key factor in reducing road accidents on its roads. The research methodology outlined in the article is based on an in-depth analysis of legal acts, a comparative study of international and national road safety standards, and a review of successful international practices in this field. This approach allows for a comprehensive assessment of the role of international cooperation in improving national road traffic safety policies. In conclusion, the author emphasizes that international cooperation not only contributes to improving infrastructure and regulatory frameworks but also stimulates the further development of a road safety culture. For Ukraine, it is crucial to continue cooperation with international organizations and adapt global standards to its conditions. This will not only improve road traffic safety but also reduce the accident rate on its roads.

A Journey Along the Boulevard of Bioactive Compounds from Natural Sources, with Cosmetic and Pharmaceutical Potential: Bee Venom, Cobra Venom, Ficus carica

Animal venom and plant extracts have been used since ancient times in traditional medicine worldwide. Natural components, valued for their safety and effectiveness, have been consistently used in cosmetic and pharmaceutical applications. We propose a journey along the boulevard of active compounds from natural sources, where bee venom (BV), cobra venom (CV), and Ficus carica reveal their individual therapeutic and cosmetic properties. The originality of this review lies in exploring the synergy of these bioactive sources, an approach that has not been presented in the literature. Although BV, CV, and Ficus carica have different origins and compositions, they have multiple common pharmacological and cosmetic actions, which make them ideal for inclusion in various products that can be used for skin care and health in general. Their anti-inflammatory, antioxidant, immunomodulatory, antimicrobial, neuroprotective, and regenerative properties give them an essential role in the creation of potential innovative and effective products in the pharmaceutical and cosmetics industry. Although many plant extracts have antioxidant and anti-inflammatory properties, Ficus carica was chosen due to its complex biochemical composition, which provides valuable benefits in skin regeneration and protection against oxidative stress. According to the International Nomenclature of Cosmetic Ingredients (INCI), Ficus carica is used in the form of an extract of fruits, leaves, juice, bark or stem, each having specific applicability in topical formulations; due to the diversity of bioactive compounds, it can amplify the effectiveness of BV and CV, helping to enhance their beneficial effects and reducing the risk of adverse effects, due to its well-tolerated nature. Thus, this combination of natural ingredients opens up new perspectives in the development of innovative products, optimizing efficiency and maintaining a favorable safety profile. In this context, due to the reported experimental results, the three natural sources caught our attention, and we conceived the present work, which is a review made following the analysis of the current progress in the study of the bioactive compounds present in BV, CV, and Ficus carica. We focused on the novelties regarding pharmacological and cosmetic actions presented in the literature, and we highlighted the safety profile, as well as the modern approaches regarding the delivery and transport systems of the active substances from the three natural sources, and we evaluated their prospects in therapeutic and cosmetic use. This paper not only expands our knowledge of bioactive compounds, but it can also generate new ideas and motivations for the research and development of innovative treatments and skincare methods.

Research on airport express train schedule optimization based on demand-driven air-rail intermodal transportation

The optimization of the train frequency of the Airport express line (AEL) is crucial for improving the efficiency of air-rail intermodal transport. It directly influences passenger transfer convenience and overall service quality, thereby bolstering the competitiveness of the transport system This study focuses on the optimization of “AEL and Flight Succession” in the context of air-rail intermodal transport. By analyzing the departure and landing time of airport flights, we assess the demand from various passenger flows and identify key factors that impact the connection between the AEL and flights. Based on these factors, we develop a demand-driven optimization model for AEL frequency, aimed at minimizing total travel time and the number of unserved passengers. A simulated annealing algorithm is employed to solve this model. The Lanzhou-Zhongchuan AEL serves as a case study for validation. The results demonstrate that the optimized schedule reduces total passenger travel time costs by 0.93% and 3.82%, respectively, while accounting for passenger time sensitivity and fairness principles, with a difference of 2.89% between these scenarios. In addition, the optimization scheme decreases the number of unserved passengers by 14.7% and reduces the percentage of flights and trains failing to meet occupancy constraints by 17%. This study illustrates that the schedule optimization strategy not only effectively increases the number of served passengers but also significantly reduces total intermodal and commuter travel time. Such findings provide a solid scientific foundation for AEL operations and management to develop a more efficient and rational train schedule in the context of air-rail intermodal transport.

Towards safety and efficiency by assessment of positioning approaches for Enhanced navigation in road tunnels

The main objective of this article is to provide an evaluation of appropriate technologies for positioning in road tunnels. In tunnels, there are even more strict requirements for operation and safety compared to regular road infrastructure. The operation, traffic efficiency, and safety could be increased by using technological equipment, intelligent transport systems, smart traffic solutions, navigations, etc. However, these require location information to run smoothly with their proper functionality. Positioning is based mainly on the Global Navigation Satellite System (GNSS) approach and is very common because of its availability. However, in tunnels, the GNSS signals are shielded by the tunnel structure, and thus the GNSS approach is inappropriate. The article points out that the alternative way of localization could have a profound impact and could be considered by policy makers, tunnel infrastructure directors, safety regulators, etc. In the article, the evaluation of alternative positioning approaches in the GNSS denied environment is presented. The evaluation was carried out using a comprehensive analysis with multi-criterial decisions based on the combination of the Saaty and Metfessel methods. According to the stated criteria, the Bluetooth Low Energy (BLE) based approach received the best overall evaluation score, and is 1.62 times more appropriate compared to other on average. The selection of BLE is caused mainly by its relatively low investment and operational costs, together with low requirements on its applicability in tunnels without any intervention or modification of existing or already deployed systems. The BLE based positioning is also available for a wide range of users. Therefore, the BLE based solution is proposed and presented by practical examples of experimental measurements in the Blanka tunnel.

Assessment of Safety Probability of Fastening Operations in Loading-unloading Work Process

One of the important strategic objectives in the target programs for economic and social development adopted by the Government of Georgia is to improve the coordination of all types of transport – sea, rail, road, air, and pipeline. The methods of organizing and managing the transport system at different levels greatly impact solving the problems faced by water transport. Therefore, research in the field of improving the organization and management of the transport hub (port), as an integral part of this system, plays an important role in increasing the traffic volume and service quality of all types of transport on the transport corridors of Georgia. Foreign and domestic experience shows that a large percentage of waiting times for cargo operations by ships and berths is mainly due to the lack of coordinated actions between the adjacent modes of transport and ports and the imperfection of the organization and management of loading and unloading processes in ports. In this regard, it is necessary to focus on identifying and eliminating "vegetables". First of all, this link of the transport system connects water and land transport routes. Transport communications have long been called the arteries of life. Without them, the economy's rise and the country's prosperity, even if it has huge natural resources, is impossible. Whoever controls the transportation system holds the levers of economic management, which means that he can decide the fate of the entire state. The development of transport communications of the global transport system puts new demands on the quality of functioning of the existing intermodal corridor through Georgia. In particular, the transport corridor created by the EU countries under the name ITC TRACECA creates new challenges for the existing transport system of Georgia to maintain the transit cargo flows between Europe and Asia in competition with the seaports of Georgia, Azerbaijan, and partly Ukraine and Russia. In this regard, all the main directions of improving the organization and management of the technological processes of seaports become relevant: (i) increasing the capacity of berths and transport complexes in the Black Sea ports of Georgia to the maximum limit by reducing costs; (ii) creating new methods for identifying capacity reserves, which will ensure the competitiveness of Georgian seaports in competition with these ports; (iii) speeding up the process of transit cargo transportation through seaports, as well as reducing the processing time of cargo going to export and import in Georgian ports. Keywords: Transport hub, organization of technological processes, ship unloading work.

Role of RyR2 and SERCA2a in the Cardioprotective Effects of Vincanine and Pyrazoline Alkaloids

In the conducted studies, the effect of vincanine and pyrazoline indole alkaloids on cardiac muscle cell sarcoplasmic reticulum (SR) Ca2+-transport systems (RyR2 and SERCA2a) was investigated under normal and hypoxic conditions. The effect of vincanine and pyrazoline on ryanodine receptor (RyR2) was evaluated in the presence of ruthenium red and it was found that the role of RyR2 in the positive inotropic effect of these alkaloids is small. Also, in the presence of cyclopiazonic acid (IC50 = 5.6 µM), an inhibitor of sarcoplasmic reticulum Ca2+-ATPase (SERCA2a), the positive inotropic effect of vincanine and pyrazoline alkaloids was reduced. In general, the positive inotropic effects and cardioprotective properties of vincanine and pyrazoline alkaloids are mediated by modulation of SERCA2a function. HIGHLIGHTS Vincanine and pyrazoline indole alkaloids have a positive inotropic effect on the force of papillary muscle contraction of the rat heart. Vincanine and pyrazoline indole alkaloids have a cardioprotective effect and effectively eliminate the disturbances in the papillary muscle contractile activity of the rat heart caused by hypoxia. Vincanine and pyrazoline alkaloids effectively reverse hypoxia-induced SERCA2a dysfunction and normalize changes in rat cardiac papillary muscle contractile activity. GRAPHICAL ABSTRACT

Positivity and bound preserving well-balanced high order compact finite difference scheme for Ripa and pollutant transport model

We construct a fourth-order accurate compact finite difference scheme that is well-balanced, positivity-preserving of water height, and bound-preserving of temperature for Ripa and concentration for pollutant transport systems. The proposed scheme preserves the still-water steady state and the positivity of water height. It also maintains concentration bounds for pollutants across nonflat bottom topographies, regardless of the presence of a pollutant source. Our approach incorporates water height and pollutant concentration constraints within the same discretization, utilizing weak monotonicity and a simple bound-preserving limiter while preserving the well-balanced property. Through extensive numerical simulations encompassing Ripa and pollutant transport models, we demonstrate the effectiveness of our method, verifying its well-balanced property, high-order accuracy, positivity-preserving, and bound-preserving capabilities.

Evaluation of Road Safety Hazard Factors in Egypt Using Fuzzy Analytical Hierarchy Order of Preference by Similarity to Ideal Solution Process

To address road accident losses, there is a need to prioritize safety factors, especially in high-risk locations on the road network, toward assuring a sustainable transport system. This paper proposes an approach for quantitative risk assessments of safety factors in hazardous road locations and involves the integration of the Fuzzy logic model, the Analytic Hierarchy Process (FAHP) and the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). This new innovative method offers a way to prioritize and select safety factors associated with hazardous locations using a hierarchical structure. To demonstrate the applicability of this method, a case study was conducted in Egypt. The assessment process involved active participation by professionals through multiple expert meetings. This collaborative approach ensures that the assessment incorporates valuable real-world knowledge and experiences. It analyzed road safety hazardous conditions across various sections, including intersections, non-intersection sections, narrow bridge sections, and curve sections. The application of FAHP-TOPSIS enables the determination of weights for safety factors within each section, facilitating the evaluation of safety indices between them and ranking the safety hazard sections. The achieved analysis revealed that the hazard safety factor index is comparatively higher in curved sections compared to other types of sections. Light utility poles and road barriers significantly affected the hazard index. By utilizing this approach, governments may make informed decisions regarding the allocation of resources and the implementation of safety measures at hazardous road locations.

TRANSPORTE AQUAVIÁRIO: AVALIAÇÃO DE UMA NOVA ALTERNATIVA DE MOBILIDADE INTERURBANA PALMAS-TO/PORTO NACIONAL-TO

Waterway transportation between Palmas and Porto Nacional on the Tocantins River is a promising alternative to foster regional development. This study aims to assess the feasibility of a waterway transportation system connecting these two cities, highlighting benefits such as reduced dependence on road transportation, logistical efficiency, economic development, and tourism potential. The research employed a quantitative approach through questionnaires administered to residents of both cities to capture perceptions of current mobility and acceptance of the new mode. Results indicate a strong public acceptance of waterway transportation (78.4%) and a perception that the accessibility, mobility, and infrastructure of the current road transport system are limited, underscoring the positive potential impact of implementing a waterway system.

Surgical Outcomes of Patients With Heterotaxy Syndrome - The Japanese Congenital Cardiovascular Surgery Database.

Cardiac malformations are a major component of heterotaxy syndrome and result in significant mortality and morbidity. This multicenter nationwide Japanese study evaluated mortality and morbidity after initial surgical palliation for patients with heterotaxy syndrome and determined predictors for mortality and morbidity among patients enrolled in the study. The Japanese Congenital Cardiovascular Surgery Database (JCCVSD) collects clinical data from 119 domestic institutions specializing in congenital heart disease, covering almost all major congenital heart surgery programs in Japan. Clinical data on preoperative, operative, and postoperative characteristics and survival data within 30 and 90 days were available from the JCCVSD database. Of the 561 patients with heterotaxy syndrome who underwent any of 8 specific initial cardiovascular surgeries, 45 (8.2%) and 75 (13.4%) had died at 30 and 90 days, respectively. Preoperative emergency transport, type of heterotaxy syndrome, low hospital volume, the repair of total anomalous pulmonary vein connection, and the repair of a common atrioventricular valve were identified as significant predictive factors for operative mortality. Improvements in some medical circumstances, such as fetal diagnosis and the patient transport system, will be needed to improve outcomes for severely ill patients with heterotaxy syndrome. This study describes early outcomes for the largest number of main cardiovascular surgeries to date in infants with heterotaxy syndrome.

How has the COVID-19 pandemic reshaped the aviation network? A comparative pre- and during-pandemic analysis

The COVID-19 pandemic has profoundly impacted international flights, leading to substantial economic repercussions for the global tourism industry. While existing research has explored the resilience and recovery of the air transport system during the pandemic, this analysis delves into the structural transformation of the air transportation network within “the Belt and Road” region through a quantitative analysis. The findings reveal three critical aspects: (1) The pandemic caused a marked reduction in air transport connectivity, with flight frequency and route connectivity between cities decreasing by 27.82% and 35.87%, respectively, although the basic aviation framework remained intact. This impact varied across different administrative levels, regions, and distances, due to the impact of different countries' pandemic policies. Transnational connections were particularly hard-hit, experiencing more severe disruptions than domestic routes. (2) Significant shifts occurred in the rankings of aviation hubs. For example, cities like Singapore and Doha rose in prominence, while traditional hubs such as Moscow and Beijing saw a decline in their rankings. This shift reflects a reconfiguration of key nodes within the aviation network. (3) The network structure underwent significant reorganization and decentralization, transitioning from a conventional core-periphery model to a hybrid structure that blends core-peripheries with local communities. This transformation demonstrates the network's adaptability and its capacity to develop alternative structures in response to sudden external shocks like the COVID-19 pandemic. The insights from this analysis offer valuable guidance for policy-making and the development of emergency measures to better prepare for and mitigate future disruptions in air transport. The analysis underscores the importance of flexible and adaptive strategies in managing aviation networks, particularly in the face of global challenges.

Increased ridership and improved affordability: Transforming public transport subsidies in developing contexts

In Latin American cities, the affordability of public transport presents a significant obstacle to mobility. To address this challenge, several cities have implemented subsidies. Understanding the effectiveness of these subsidies is crucial, particularly in cities where a substantial portion of the population, especially those with low incomes, rely on public transport systems. This paper presents a case study conducted in Bogotá, Colombia, employing a randomized controlled field experiment involving 1607 participants. In this intervention, a randomly selected group of frequent public transport users received a cash transfer on their travel cards (a transport voucher) for four months. We aim to estimate the causal effects of providing these vouchers on ridership and affordability. The findings indicate that vouchers on average, increased ridership by up to 9% compared to the control group. This increase was most pronounced on weekdays and during peak hours. Vouchers proved particularly advantageous for populations with low fare-demand elasticity, who constitute the primary users of public transport. Furthermore, it improved their affordability by between 18 and 26%. In summary, our results indicate that providing subsidies in the form of vouchers can effectively boost public transport usage, thereby enhancing affordability for users.