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Building materials and components account for about 10% of the world's anthropogenic greenhouse gas emissions. Carbonate decomposition and fuel combustion from the cement production process are responsible for almost 7% of carbon dioxide emissions. Since clinker is the most impacting component of ordinary Portland cement, this paper presents a statistical analysis of the life cycle impacts of 41 recipes of grey clinker produced in Europe from 2015 to 2023 to identify the consumption impact categories (e.g., fossil fuels, renewable and non-renewable secondary fuels) which better explain the assessment of the Global Warming Potential (GWP), typically exploited to quantify the environmental impact of clinker production. More in detail, several regression methods are applied to the available dataset to build predictive models for GWP and to determine the most relevant impact categories. The regression models are then compared with respect to their statistical accuracy and goodness of fit. The results provide information that can support cement producers in developing low-impacting cement recipes.

Premature debonding between carbon fiber-reinforced polymer (CFRP) and concrete is a critical issue in structural reinforcement applications, often leading to a significant reduction in the load-carrying capacity of the system. This failure mode is typically initiated by inadequate adhesion at the interface, compromising the effectiveness of CFRP in enhancing the structural performance of concrete elements. To address these issues, this study explores the impact of silica sand on the mechanical and adhesion properties of epoxy resin composites. Initially, this paper investigates the physical and mechanical properties of epoxy resin composites by varying the ratios of silica sand from 0% to 15% by volume. Subsequently, it examines the effectiveness of these composites as sealing materials to enhance the bond strength between CFRP and concrete. Incorporating a 10% silica content improves the mechanical properties of the epoxy resin, with the tensile strength increasing from 29.47 MPa to 35.52 MPa and an elastic modulus from 4.38 GPa to 5.83 GPa. Furthermore, silica sand enhances the adhesion strength between CFRP and concrete, as confirmed by the increase in the pull-out force from 14.21 kN to 18.79 kN. Silica particles improve surface roughness and interlocking, contributing to a better load distribution and stress transfer at the interface. Therefore, silica-filled epoxy resin is an efficient material for CFRP–concrete bonding applications.

The tunnel industry has started focusing on the maintenance and management challenges of an existing infrastructure. It is an urgent matter in industrialised countries, where the stakeholders’ attention is increasing at a fast pace considering the incidents and the disruptions caused by improper monitoring and maintenance. This paper presents an innovative methodology to survey and inspect existing railway tunnels through multi-dimensional mobile mapping systems. The proposed approach belongs to the digital strategies for infrastructure maintenance. An integrated multidimensional survey system (ARCHITA) allows for collecting information necessary for the diagnostics of a structure with non-destructive tests. Linear cameras, thermographic cameras, and ground-penetrating radars acquire data to be digitalised and manipulated in different IT environments. The results, in terms of the collected data on structural defects, allow for a new approach for the Management and Identification of the Risk for Existing Tunnels (MIRET). The innovative approach aims at a smart integration of information and models for the Facility Management of the transport system. The workflow for the digitalisation and diagnosis from mobile mapping data has been implemented on two 40km-long metro tunnels.

Citrullinemia type I is a rare autosomal-recessive disorder caused by deficiency of argininosuccinate synthetase (ASS1). The clinical presentation includes the acute neonatal form, characterized by ammonia and citrulline accumulation in blood, which may lead to encephalopathy, coma, and death, and the milder late-onset form. Current treatments are unsatisfactory, and the only curative treatment is liver transplantation. We permanently modified the hepatocyte genome in lethal citrullinemia mice (Ass1fold/fold) by inserting the ASS1 cDNA into the albumin locus through the delivery of two AAV8 vectors carrying the donor DNA and the CRISPR-Cas9 platform. The neonatal treatment completely rescued mortality ensuring survival up to 5 months of age, with plasma citrulline levels significantly decreased, while plasma ammonia levels remained unchanged. In contrast, neonatal treatment with a liver-directed non-integrative AAV8-AAT-hASS1 vector failed to improve disease parameters. To model late-onset citrullinemia, we dosed postnatal day (P) 30 juvenile animals using the integrative approach, resulting in lifespan improvement and a minor reduction in disease markers. Conversely, treatment with the non-integrative vector completely rescued mortality, reducing plasma ammonia and citrulline to wild-type values. In summary, the integrative approach in neonates is effective, although further improvements are required to fully correct the phenotype. Non-integrative gene therapy application to juvenile mice ensures a stable and very efficient therapeutic effect.

The extraction and utilization of non-renewable mineral resources impose significant transportation and economic challenges in infrastructure construction. At the same time, recycling fly ash derived from the bottom ash in municipal solid waste incineration residues (MSWIRs) presents a waste management hurdle. This study investigates the viscoelastic characteristics and mechanical performances at different scales of asphalt mastic and mixture with fly ash from MSWIRs. Firstly, Fourier transform infrared spectrometry (FTIR) was adopted to distinguish the physically blended states of asphalt and fillers. Then, a frequency test using a dynamic shear rheometer (DSR) was conducted to construct viscoelastic master curves, focusing on asphalt mastic. A dynamic modulus test characterized the viscoelastic behavior at the asphalt mixture scale. Furthermore, the mechanical performances of asphalt mixtures were evaluated, including the resilient modulus through indirect tension tests, moisture susceptibility via the immersed Marshall stability test, and anti-cracking properties with a low-temperature bending test. The FA incorporation in the mixture decreased the immersion residual stability by 7.40%, and increased the flexural tensile strength by 5.03% and the stiffness modulus by 78.67%. The mechanical evaluation of the mixture with FA could meet the application requirements of the asphalt layer. Finally, statistical analyses were conducted to present strong correlations (coefficient R2 over 0.70) among the mechanical results. Fly ash in asphalt mixtures revealed potential as a sustainable approach for waste reuse in road construction. Additionally, substituting mineral fillers at the mastic scale significantly influences the viscoelastic characteristics and mechanical performances of asphalt materials at the mixture scale.

Bus lanes play a crucial role in urban areas as their primary objective is to increase public transport efficiency and help traffic and public transit systems flow more smoothly. This study starts with traffic and climate monitoring to verify asphalt bus lanes in Rome, Italy, according to the Italian Pavement Design Catalogue published in 1995. KENLAYER software calculated the stress-strain conditions under real traffic loads (i.e., hourly passages of urban buses, considering their axle load and seat occupancy rate), typical subgrade bearing capacity (i.e., resilient modulus equal to 90 MPa), current climate conditions, and road material properties. Then, the Mechanistic-Empirical Pavement Design Guide (MEPDG) was used to verify the response of the pavement structure. The fatigue verification of bound materials resulted in damage values much lower than 1 at the end of the 20-year service life (i.e., 0.12 with the Asphalt Institute and 0.31 with the Marchionna law, respectively) and highlights that the Italian catalogue’s sheets are overdesigned. On the other hand, the rutting verification according to MEPDG is not satisfied after an 11-year service life (i.e., the total rutting is equal to 1.50 cm), forcing frequent and expensive maintenance of wearing and binder courses. Therefore, the results confirm the validity of the Italian catalogue for fatigue service life and suggest the need for high-performance asphalt to prevent early rutting due to bus traffic increasing by load and frequency in previous decades.

No theoretical model effectively explains the blistering process, which provokes functional distress in asphalt pavements worldwide. This study focuses on the possible causes of blistering, the physical processes that drive blistering, the role of asphalt properties, and the uncertainties and gaps in the current knowledge. This paper analyzes peer-reviewed studies on pavement blistering published between 1959 and 2022 retrieved in a systematic literature review to justify and model this distress observed on sidewalks, airports, and bridges. According to the scientific literature, high surface temperatures due to solar radiation are the common factor responsible for uplifting, but several causal mechanisms have been investigated. Indeed, chemical reactions, evolutionary materials, thermal buckling, and physical reactions are the generally recognized causes. Their effects on pavement smoothness vary according to the various interdependent geometrical, physical, and mechanical properties of asphalt mixtures and the boundary conditions. Both the mix design and construction processes can hinder the blistering process that occurs during daytime hours of the hot season, right after the work is finished or a few years later. Further research should identify measures to prevent bulges whose management after uplift is difficult but necessary to avoid safety and functional issues.

Urban Heat Islands (UHIs) are expanding in anthropized areas, causing serious climatic consequences such as rising temperatures and citizens' discomfort. Several studies have identified and confirmed how the use of cool road pavements can mitigate and reduce the negative effects of UHIs. This study performs a microclimate simulation of San Pietro in Vincula Square in Rome through ENVI-Met software by replacing the current asphalt pavement in the parking area with a cool one. The proposed layout consists of light concrete pavers in the parking lots, parking aisles made of photovoltaic (PV) panels, and a perimeter hedge. The innovative use of PVs is analysed from the thermal and economic viewpoints alike. In the first case, its thermal characteristics like those of asphalt provide results in terms of air temperature, mean radiant temperature, and predicted mean vote close to the current ones. Furthermore, the energy analysis shows the PV's effectiveness in terms of economic impact. Indeed, the electricity produced by the proposed PV system is enough to light the area, and its surplus can power public activities such as electric vehicle charging. The initial investment would pay for itself in the 25-year service life as confirmed by the positive net present value (NPV), and the cash flow reveals a break-even point in the 15th year.

The topographical features of a site and the anthropogenic artefacts inside and outside the airport boundaries influence the infrastructure use. Objects penetrating the obstacle limitation surfaces (OLS) or standing outside those surfaces have to be mapped and risk-assessed because they could be a hazard to air navigation. This study aims to quantify the risk of collision between aircraft and obstacles in the airspace. There are no available procedures in the literature: the authors supposed that the obstacle type and the examined OLS affect the collision risk. The proposed risk values and amplification factors derive from interviews with technicians. The methodology has been implemented in an existing airport with 589 penetrating obstacles: the results highlight that 69.8% of obstacles imply a negligible risk, and 3.7% require further analyses by the competent aviation authority. In this study, buildings and pylons penetrating the Transitional Surface are the most hazardous obstacles.

The environmental impacts of cement manufacturing are becoming a real-time issue that requires attention. This paper investigates the mechanical and physical properties of mortars with finely ground sand as a substitute for cement. The experimental program consisted of three silica sands with a Blaine Specific Surface (BSS) area of 459 m2/kg, 497 m2/kg, and 543 m2/kg and four substitution ratios of 10%, 20%, 30%, and 40%. A total of 12 mixtures have been prepared and tested for comparison to the reference mortar. The pozzolanic effect of the sand was evaluated using thermogravimetric analysis (TGA). The results revealed that the fineness variation from 459 m2/kg to 543 m2/kg resulted in an increase of 20% and 30% in water absorption and compressive strength, respectively. However, increasing the substitution ratio from 10% to 40% led to a 40% decrease in mechanical strength and a 25% increase in water absorption. The statistical analysis of the results demonstrated that both factors under study influenced compressive strength and water absorption. The ANalysis of VAriance (ANOVA) confirmed that the proposed regression equations predict the experimental results. Further studies will investigate both the technical and environmental performances of cement mortars with finely ground silica sand.

Abstract Background Platform trial designs are used increasingly in cancer clinical research and are considered an efficient model for evaluating multiple compounds within a single disease or disease subtype. However, these trial designs can be challenging to operationalise. The use of platform trials in oncology clinical research has increased considerably in recent years as advances in molecular biology enable molecularly defined stratification of patient populations and targeted therapy evaluation. Whereas multiple separate trials may be deemed infeasible, platform designs allow efficient, parallel evaluation of multiple targeted therapies in relatively small biologically defined patient sub-populations with the promise of increased molecular screening efficiency and reduced time for drug evaluation. Whilst the theoretical efficiencies are widely reported, the operational challenges associated with these designs (complexity, cost, regulatory, resource) are not always well understood. Main In this commentary, we describe our practical experience of the implementation and delivery of the UK plasmaMATCH trial, a platform trial in advanced breast cancer, comprising an integrated screening component and multiple parallel downstream mutation-directed therapeutic cohorts. plasmaMATCH reported its primary results within 3 years of opening to recruitment. We reflect on the operational challenges encountered and share lessons learnt to inform the successful conduct of future trials. Key to the success of the plasmaMATCH trial was well co-ordinated stakeholder engagement by an experienced clinical trials unit with expert methodology and trial management expertise, a federated model of clinical leadership, a well-written protocol integrating screening and treatment components and including justification for the chosen structure and intentions for future adaptions, and an integrated funding model with streamlined contractual arrangements across multiple partners. Findings based on our practical experience include the importance of early engagement with the regulators and consideration of a flexible resource infrastructure to allow adequate resource allocation to support concurrent trial activities as adaptions are implemented in parallel to the continued management of patient safety and data quality of the ongoing trial cohorts. Conclusion Platform trial designs allow the efficient reporting of multiple treatment cohorts. Operational challenges can be overcome through multidisciplinary engagement, streamlined contracting processes, rationalised protocol and database design and appropriate resourcing.

Recurrent pregnancy loss (RPL) refers to two or more miscarriages before 20 weeks gestation. Its prevalence is 1–2%; its pathogenesis remains unexplained in more than 50% of cases, in which the cause is thought to be abnormal immune activity during placentation leading to a lack of pregnancy-induced immune tolerance. It is unknown whether immune activity is deranged in the endometrium of women with RPL. We studied the gene expression and the quantitative tissue protein levels of three immune checkpoints (CD276, which enhances cytotoxic T-cell activity, cytotoxic T-lymphocyte-associated antigen-4 [CTL-4], which reduces Th1 cytokine production, and lymphocyte activation gene-3 [LAG-3], which shows suppressive activity on Tregs and CD4+ T-cells) in endometrial samples from 27 women with unexplained RPL and in 29 women with dysfunctional uterine bleeding and previous uneventful pregnancies as controls. RNA isolation, real-time PCR, protein isolation, and ELISA were performed. CD276 gene expression and protein tissue levels were significantly lower in the endometrium of the RPL group than in the controls, whereas both CTL-4 and LAG-3 were significantly higher. This difference suggests defective endometrial immune regulation and overactivation of immune response in women with a history of RPL, at least in relation to controls with dysfunctional uterine bleeding and previous normal reproductive history.

Controlled studies demonstrate that it is possible to improve muscle strength in people of all ages, including older populations. Clinically, it is relevant to establish whether a resistance training program (26 sessions of 60 minutes of aerobic workout plus 30 minutes of circuit training for muscular strength) leads to comparable strength gains in overweight/obese persons of different ages. The purpose of this study was to show the effects of a structured, supervised exercise intervention program on muscle strength, flexibility, and other health-related measures (anthropometrics, body composition, blood pressure and cardiometabolic risk) in 181 overweight/obese people ages 19–74 years old (young, 19–48 years; middle aged, 49–59 years; and older 60–74 years). We studied changes in muscular strength, anthropometric measures, body composition, basal blood pressure, and cardio metabolic risk. An increase in the dynamic muscular strength of the muscular groups evaluated (p

Background: The rapid outbreak of Coronavirus disease 2019 (COVID-19) has posed several challenges to the scientific community. The goal of this paper is to investigate the spread of COVID-19 in Northern Italy during the so-called first wave scenario and to provide a qualitative comparison with the local highway net. Methods: Fixed a grid of days from February 27, 2020, the cumulative numbers of infections in each considered province have been compared to sequences of thresholds. As a consequence, a time-evolving classification of the state of danger in terms of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections, in view of the smallest threshold overtaken by this comparison, has been obtained for each considered province. The provinces with a significant amount of cases have then been collected into matrices containing only the ones featuring a significant amount of cases. Results: The time evolution of the classification has then been qualitatively compared to the highway network, to identify similarities and thus linking the rapid spreading of COVID-19 and the highway connections. Conclusions: The obtained results demonstrate how the proposed model properly fits with the spread of COVID-19 along with the Italian highway transport network and could be implemented to analyze qualitatively other disease transmissions in different contexts and time periods.

At the international level, increasing efforts have been made to assess the burdens of transport by road and adopt effective mitigation strategies. In this study, life cycle analyses have been carried out to compare the environmental performances of 100 m-long highway sections during 60 year-service life. According to the standard EN 15804, emissions and abiotic depletions have been assessed for four different cross-sections (i.e., embankment, trench, bridge, and tunnel) paved with asphalt or concrete and traveled by motor vehicles during their service life. The software SimaPro gave results in terms of construction, operation, and traffic: whatever the pavement, trenches are the least impactful sections, and the opposite is for tunnels (e.g., 5.72 × 106 and 1.12 × 107 kg CO2 eq. respectively across the entire life with rigid pavement). As concerns the construction phase, flexible pavements imply fewer burdens than rigid ones; the opposite is across the entire life. Therefore, the adoption of green strategies to manage roads requires deep knowledge to implement effective procedures at different life cycle stages.

Repairing potholes is a task for municipalities to prevent serious road user injuries and vehicle damage. This study presents a low-cost, high-performance pothole monitoring system to maintain urban roads. The authors developed a methodology based on photogrammetry techniques to predict the pothole’s shape and volume. A collection of overlapping 2D images shot by a Raspberry Pi Camera Module 3 connected to a Raspberry Pi 4 Model B has been used to create a pothole 3D model. The Raspberry-based configuration has been mounted on an autonomous and remote-controlled robot (developed in the InfraROB European project) to reduce workers’ exposure to live traffic in survey activities and automate the process. The outputs of photogrammetry processing software have been validated through laboratory tests set as ground truth; the trial has been conducted on a tile made of asphalt mixture, reproducing a real pothole. Global Positioning System (GPS) and Geographical Information System (GIS) technologies allowed visualising potholes on a map with information about their centre, volume, backfill material, and an associated image. Ten on-site tests validated that the system works in an uncontrolled environment and not only in the laboratory. The results showed that the system is a valuable tool for monitoring road potholes taking into account construction workers’ and road users’ health and safety.

Eosinophilic/T-cell chorionic vasculitis (ETCV) is an idiopathic lesion composed of eosinophils, CD3+ T lymphocytes, and histiocytes. In twins, ETCV may affect only one chorionic plate, a feature defined as “discordant”. We present a case of ETCV discordance in a diamniotic dichorionic placenta at 38 weeks of gestation, in which the female twin was small for gestational age, weighing 2670 g (25th percentile). The corresponding placental territory presented ETCV in two close chorionic vessels with concordance of the fetal inflammatory response. Immunohistochemistry showed an abundance of CD3+/CD4+/CD25+T lymphocytes, CD68 PG M1+ macrophages, and scattered CD8+ T cells with focal TIA-1 positivity. Granzyme B, CD20 B lymphocytes, and CD56 natural killer cells were negative. High-grade villitis of unknown etiology (VUE) was additionally found and displayed comparable ETCV findings, except for an equivalent ratio of CD4+/CD8+ T cells, but TIA-1 was focally expressed. VUE was associated with chronic histiocytic intervillositis (CHI). The combination of ETCV, VUE, and CHI may have been responsible for reduced fetal growth. Concordance was observed in the ETCV and TIA-1 expression, both in ETCV and in VUE, which is a maternal response. These findings may suggest a common antigen or chemokine pathway to which both mother and fetus accordingly responded.

Circulating tumour DNA can provide useful information on disease burden. Here, the authors analysed circulating tumour DNA from 800 patients from a breast cancer clinical trial and investigate the subclonal nature of the disease, and identify DNA mutations associated with resistance and poor survival.

Abstract Gestational diabetes mellitus (GDM) and preeclampsia (PE) are both characterized by endothelial dysfunction and GDM women have higher incidence of PE. The placenta plays a key role in PE pathogenesis but its contribution to PE during GDM remains unclear. Herein, we compared placental and maternal blood anti-angiogenic soluble fms-like tyrosine kinase-1 (sFlt1) and pro-angiogenic Placental Growth Factor (PlGF) expressions in GDM and GDM-PE pregnancies compared to controls (CTRL) and PE cases. Electrochemiluminescence immunoassays showed a significantly higher maternal blood sFlt1/PlGF values in GDM-PE relative to CTRL and GDM pregnancies. We reported that placental PlGF gene expression was significantly decreased in GDM, PE and GDM-PE relative to CTRL. However, PlGF protein levels were significantly increased in GDM and GDM-PE relative to CTRL and PE placentae. Finally, sFlt1 gene expression was significantly increased in PE relative to CTRL, GDM and GDM-PE placentae. In contrast, sFlt1 protein expression was significantly decreased in GDM-PE relative to CTRL, GDM and PE placentae. Finally, higher sFlt1/PlGF ratio in GDM-PE maternal blood suggest that sFlt1 overproduction is related to PE onset also in GDM pregnancies even though characterized by a less severe endothelial dysfunction in terms of angiogenic biomarkers.

Environmental safeguards promote innovative construction technologies for sustainable pavements. On these premises, this study investigated four hot mix asphalt (HMA) mixtures—i.e., A, B, C, and D—for the railway sub-ballast layer with 0%, 10%, 20%, and 30% reclaimed asphalt pavement (RAP) by total aggregate mass and a rejuvenator additive, varying the bitumen content between 3.5% and 5.0%. Both Marshall and gyratory compactor design methods have been performed, matching the stability, indirect tensile strength, and volumetric properties of each mixture. Dynamic stiffness and fatigue resistance tests provided mechanical performances. Laboratory results highlighted that the RAP and the rejuvenator additive increase the mechanical properties of the mixtures. In addition, the comparative analysis of production costs revealed up to 20% savings as the RAP content increased, and the life cycle impact analysis (LCIA) proved a reduction of the environmental impacts (up to 2% for resource use-fossils, up to 7% for climate change, and up to 13% for water use). The experimental results confirm that HMA containing RAP has mechanical performances higher than the reference mixture with only virgin raw materials. These findings could contribute to waste management and reduce the environmental and economic costs, since the use of RAP in the sub-ballast is not, so far, provided in the Italian specifications for railway construction.

Home-to-school routes are very sensitive areas: they represent, for children, a learning tool for their everyday activities, but if poorly designed, maintained and equipped they can expose them to traffic risks. Sidewalks' inappropriate level of service and poor maintenance, especially, are main factors contributing to walking unsuitability, thus to poor comfort and safety levels for young pedestrians, and more in general for all the vulnerable non-motorized road users. This paper deals with a methodology specifically developed to highlight the quality of the urban environment where the home-to-school routes are located, according to four main criteria: wellbeing, usage, appearance, and safety and security. Each criterion is associated with a checklist including the most relevant features to assess, with a focus on maintenance as a key parameter to create safe and comfortable routes to school. An application, a case study in Rome, where the lack of regular maintenance results into a network of unsafe sidewalks, is also presented, analyzing three different areas where a number of schools are located. Detours when approaching school premises were surveyed, due to the levels of distresses and linked to the poor comfort and safety levels. As the mutual influence of built environment over road safety and maintenance requirements for home-to-school paths is not largely investigated thus far, the paper's goal is to provide advanced knowledge for studies and applications further afield.

Although the construction of block pavements has grown fast in the last decades, there is still a need for simple tools that could be applied to design them. This paper analyzed and verified concrete block pavements for urban and local roads composed of rectangular concrete pavers with plane side surfaces (no interlocking effect). The examined blocks were laid on a bedding sand layer, a cement treated base layer and a granular unbound foundation layer. The commercial finite element (FE) software ANSYS® was used to calculate the response of the pavement when subjected to different loading, construction configurations. Three wheel positions, five blocks patterns, three bedding sand thicknesses and joints gaps have been considered to evaluate stress-strain condition on pavement materials. Fatigue and rutting verification was performed respectively for bound and unbound pavement materials using analytical curves available in the literature. At the end of this study, a proposal for a catalogue is presented. It has nine pavement sets, because it takes into account three values of subgrade capacity (30, 90, and 150 MPa of resilient modulus) and three levels of traffic (400,000, 1,500,000, and 4,000,000 passages of commercial vehicles during the service life). The obtained results provide an inexpensive procedure for the preliminary design of concrete block pavements. Keywords: Block pavement, Finite element model, Concrete pavers, Local roads, Urban roads

The world is facing new challenges due to the SARS-CoV-2 (Severe Acute Respiratory Syndrome CoronaVirus 2) virus outbreak identified in Wuhan, China in December 2019. The aim of this paper is to investigate and discuss how cities are being managed in the anti-pandemic “new normal”. And this in light of unexpected phenomena such as: the on-going modal shift from public transport to private modes vs the new momentum gained by walking, and social lifestyles dictated by confinement first and now by unregulated behavior, also affecting land use. Add to this unpreparedness of pre-pandemic transport policies and the new emerging opportunities; the fresh directions for research and development, for example in the field of urban mobility management. With the additional goal to contribute to further advance the research, the paper also clearly shows that the crisis can be overcome only by considering different fields of action and by considering our common past.

Road asphalt pavements cover a high percentage of urban size and contribute to heat islands. This study proposed a new method to cool asphalt pavement by incorporating a kind of hybrid mineral filler (HMF) with high emissivity into a reference asphalt mixture prepared with limestone mineral filler (LMF). The physical, emissive, solar reflective, and rheological properties of asphalt mastic and the thermal performances of asphalt mixture were covered to investigate the possibility of the proposed strategy. From Fourier transform infrared spectrum test, it can be found that HMF was physically blended with asphalt. The emissivity results show that HMF increased the emissivity of asphalt mastic from 0.9204 to 0.9820. The asphalt mastic containing HMF had similar solar reflectance with the control one. In addition, HMF could enhance the rutting resistance of asphalt mastic according to the results of multiple stress creep recovery tests. When HMF replaced LMF, the thermal conductivity of the asphalt mixture with HMF increased by 0.26 W/(m·K) (the reference value was 1.72 W/(m·K)). The combined effect of high emissivity and thermal conductivity led to a lower surface temperature (i.e., −5.4 °C) in the tests. The results of this study demonstrate that HMF is a potential material to cool asphalt pavements.

Ongoing climate change is manifesting in the expansion of the urban heat island (UHI) effect. This paper evaluates the microclimate benefits of cool pavements and green infrastructures in a historical square in Rome, Italy. The ENVI-Met software enabled us to conduct a microclimatic analysis of the examined square in July 2021, through a comparison of the thermal performances of the current asphalt and sampietrini pavement (AS) with three alternatives. The proposed options are to change the existing layout to include: light concrete slabs and green furniture consisting of 5 m high trees (LC+G1), a perimeter hedge with 5 m high trees (LC+G2), and a perimeter hedge with 15 m high trees (LC+G3). The effects of the road pavements as passive countermeasures to the UHI effect are investigated in terms of air temperature (AT), mean radiant temperature (MRT), and predicted mean vote (PMV). The results show that the existing asphalt pavement is the worst option, while the cool pavement integrated with vegetation is greatly beneficial to human thermal comfort. Compared to the current layout, LC+G3 is the best scenario, because it implies an AT reduction higher than 3 °C, a MRT reduction equal to 50%, and a maximum PMV value equal to 2.2.

The attention to road safety-related issues has grown fast in recent decades. The experience gained with these themes reveals the importance of considering these aspects in the resource allocation process for roadside and guardrail improvement, which is a complex process often involves conflicting objectives. This work consists on defining an innovative methodology, with the objective of calculating and analysing a numerical risk factor of a road. The method considers geometry, accident rate, traffic of the examined road and four categories of elements/defects where the resources can be allocated to improve the road safety (safety barriers, discrete obstacles, continuous obstacles, and water drainage). The analysis allows the assessment of the hazard index, which could be used in decision-making processes. A case study is presented to analyse roadsides of a 995 km long road network, using the cost-benefit analysis, and to prioritize possible rehabilitation work. The results highlighted that it is suitable to intervene on roads belonging to higher classes of risk, where it is possible to maximize the benefit in terms of safety as consequence of rehabilitation works (i.e., new barrier installation, removal and new barrier installation, and new terminal installation). The proposed method is quantitative; therefore, it avoids providing weak and far from reliable results; moreover, it guarantees a broad vision for the problem, giving a useful tool for road management body. Keywords: Roadside safety, Guardrail improvement, Optimization, Resources allocation, Road management

Despite Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) -induced Oxidative Stress (OxS) being well documented in different organs, the molecular pathways underlying placental OxS in late-pregnancy women with SARS-CoV-2 infection are poorly understood. Herein, we performed an observational study to determine whether placentae of women testing positive for SARS-CoV-2 during the third trimester of pregnancy showed redox-related alterations involving Catalase (CAT) and Superoxide Dismutase (SOD) antioxidant enzymes as well as placenta morphological anomalies relative to a cohort of healthy pregnant women. Next, we evaluated if placental redox-related alterations and mitochondria pathological changes were correlated with the presence of maternal symptoms. We observed ultrastructural alterations of placental mitochondria accompanied by increased levels of oxidative stress markers Thiobarbituric Acid Reactive Substances (TBARS) and Hypoxia Inducible Factor-1 α (HIF-1α) in SARS-CoV-2 women during the third trimester of pregnancy. Importantly, we found an increase in placental CAT and SOD antioxidant enzymes accompanied by physiological neonatal outcomes. Our findings strongly suggest a placenta-mediated OxS inhibition in response to SARS-CoV-2 infection, thus contrasting the cytotoxic profile caused by Coronavirus Disease 2019 (COVID-19).

We tested the pro-angiogenic and anti-inflammatory effects of human placenta-derived mesenchymal stromal cells (hPDMSCs)-derived conditioned media (CM) on a mouse model of preeclampsia (PE), a severe human pregnancy-related syndrome characterized by maternal hypertension, proteinuria, endothelial damage, inflammation, often associated with fetal growth restriction (FGR). At d11 of pregnancy, PE was induced in pregnant C57BL/6N mice by bacterial lipopolysaccharide (LPS) intravenous injection. At d12, 300 μL of unconditioned media (control group) or 300 μL PDMSCs-CM (CM group) were injected. Maternal systolic blood pressure was measured from 9 to 18 days of pregnancy. Urine protein content were analyzed at days 12, 13, and 17 of pregnancy. At d19, mice were sacrificed. Number of fetuses, FGR, fetal reabsorption, and placental weight were evaluated. Placentae were analyzed for sFlt-1, IL-6, and TNF-α gene and protein expressions. No FGR and/or reabsorbed fetuses were delivered by PDMSCs-CM-treated PE mice, while five FGR fetuses were found in the control group accompanied by a lower placental weight. PDMSCs-CM injection significantly decreased maternal systolic blood pressure, proteinuria, sFlt-1, IL-6, and TNF-α levels in PE mice. Our data indicate that hPDMSCs-CM can reverse PE-like features during pregnancy, suggesting a therapeutic role for hPDMSCs for the treatment of preeclampsia.

Airport pavements should satisfy safe and regular aircraft operations; thus, it is necessary to monitor these surfaces and implement expensive maintenance and rehabilitation works. The Airport Pavement Management System (APMS) is an approach to monitor the pavement condition and to determine the priorities for intervention, to plan, and to allocate resources through procedures. The method for monitoring pavement conditions is currently adopted by the airport management company because it is necessary to the airport operability. The study focuses on the paved network of an Italian airport that is composed of a runway, a parallel taxiway and five exit taxiways. Measures of load bearing capacity, transversal and longitudinal evenness, pavement-tire adherence, and pavement distresses were collected and merged to identify the needed maintenance and rehabilitation works. The results revealed the presence of critical sections, where several structural and functional distresses were. The needed structural and functional works involved the greater parts of the runway and the parallel taxiway, and two exit taxiways. Given the high operational impact of the needed works, they were scheduled to be conducted within three phases in order to minimize the impact on the traffic, reducing the closure period to 15 consecutive days. In general, the results summarized approaches typical of different conditions: the article has highlighted that the Pavement Management System (PMS) requires multiple analyses to consider various indices and correctly manage existing pavements having different competences to conduct comprehensive and appropriate analyses. Keywords: Airport pavement, Pavement management system, ACN, PCN, IRI, PCI, Rutting

Plain English summary Breast cancer is a diverse and varied disease. Recent research has shown that the collection of multiple biopsies before surgery can help researchers determine how the cancer is responding to treatment and can predict for long-term outcomes. However biopsies can be uncomfortable, and sometimes clinicians and research teams in hospitals may be reluctant to offer clinical trials requiring several biopsies to patients who have been recently diagnosed with breast cancer. The Institute of Cancer Research Clinical Trials and Statistics Unit (ICR-CTSU) oversees a large number of breast cancer clinical trials where multiple biopsies are required. ICR-CTSU recognises that patient advocates (patients who have previously had, or cared for someone with, cancer) are key members of the trial design group and should be involved in the clinical trial throughout its lifespan. Patient advocates can provide reassurance regarding the acceptability of trial designs involving multiple biopsies from a patient perspective. This paper summarises patient advocate involvement in ICR-CTSU breast cancer trials activity and how this has benefited our research. Abstract The importance of collecting tissue samples in breast cancer has become increasingly recognised, as the diversity of the disease has become better known. It has been documented in recent research that tumours may change in response to treatment prior to surgery (the neoadjuvant treatment setting). The collection of sequential biopsies over time can identify changes within tumours and potentially predict how the tumour may respond to certain treatments. However, the acceptability of multiple biopsies amongst patients, clinicians and other research staff in hospitals is variable and recruitment into clinical trials requiring multiple biopsies may be challenging. The Institute of Cancer Research Clinical Trials and Statistics Unit (ICR-CTSU) is responsible for a portfolio of breast cancer trials where multiple biopsies are key to the trial design. Patient advocate involvement has been essential in helping us to design and deliver complex and innovative cancer trials which require multiple invasive tissue biopsies, often without any direct benefit to the trial participants. The views expressed by patient advocates involved in ICR-CTSU trials supports the published evidence that patients are willing to donate additional tissue for research and that clinicians’ concerns about approaching patients for trials involving multiple biopsies are often unfounded. Patient advocate involvement in ICR-CTSU trials activity takes various forms, from membership on protocol development groups and trial management groups, attendance at focus groups and forums, and presentations at trial development and launch meetings. This involvement has provided reassurance to research teams within the NHS and research ethics committees of the importance and acceptability of our trials from a patient perspective. Patient advocate involvement throughout the lifetime of our trials ensures that the patient remains central to our research considerations.

Algumas indústrias de cosméticos têm almejado a produção ecologicamente correta e o comércio de insumos provenientes da biodiversidade. É apresentada neste trabalho revisão científica para profissionais que prescrevem esses produtos. O levantamento bibliográfico foi realizado em bases de dados e pesquisas das palavras-chave. Os produtos cosméticos podem ser convencionais, naturais ou orgânicos. Os naturais contêm ingredientes de origem natural, e os orgânicos precisam conter grande parte de matérias-primas certificadas como orgânicas. Os rótulos dos produtos indicam o tipo de ingredientes usados na formulação de naturais e orgânicos, possuem diferenças, e seus conceitos devem ser bem conhecidos pelos prescritores.

This paper analysed and verified an existing block stone pavement in an urban shared area. Fatigue and rutting verification was performed respectively for bound and unbound pavement materials using analytical curves available in the literature. The commercial finite element (FE) software Abaqus® was used to calculate the response of the pavement when subjected to different loading, construction and geometrical configurations (i.e. type of analysis, shape and size of meshes, boundary conditions, and bonding contacts between the pavements layers). At the end of this study, a static model of a structure with hexahedral blocks having sides of 0.02 m, with full bonded layers and restrained horizontal displacements on the model sides, was implemented to evaluate the maximum tensile stress induced in a block when the load is applied at its centre. This analysis highlighted the need for rigorous criteria for a correct design, in order to avoid inappropriate and expensive use of road materials. Keywords: Block pavement, Commercial vehicle loads, Finite element model, Hexagonal Stone block, Pedestrian pavement, Shared area

The Cement Grouted Bituminous Mix (CGBM) is an innovative material that could be used to build airport pavements subjected to heavy concentrated loads or fuel and solvent leaks. CGBM is composed of a porous asphalt clogged with an expansive cement mixture, which fills the asphalt voids. This paper focuses on two airport pavements (i.e., a taxiway and a helipad one) to be paved in an Italian airport. For each surface, the construction and maintenance costs of a CGBM pavement and a traditional flexible pavement have been compared. The pavements should bear different traffic loads, while the weather, subgrade, and materials are the same: the fatigue and rutting verification gives structures whose cost analysis leads to different results. The CGBM solution for the taxiway has a cost comparable to that of the equivalent traditional flexible pavement (i.e., 73.87 €/m2 vs. 73.20 €/m2 during the service life). On the other hand, the overall discounted cost of the helipad surface paved with CGBM is higher than that obtained for the traditional pavement (i.e., 82.4 €/m2 vs. 67.5 €/m2). Therefore, the study demonstrates that the economic opportunity of CGBM solutions strongly depends on traffic loads.

Airport pavements should ensure regular and safe movements during their service life; the management body has to monitor the functional and structural characteristics, and schedule maintenance work, balancing the often conflicting goals of safety, economic and technical issues. This paper presents a remote monitoring system to evaluate the structural performance of a runway composed of concrete thresholds and a flexible central runway. Thermometers, strain gauges, and pressure cells will be embedded at different depths to continuously monitor the pavement’s response to traffic and environmental loads. An innovative system allows data acquisition and processing with specific calculation models, in order to inform the infrastructure manager, in real time, about the actual conditions of the pavement. In this way, the authors aim to develop a system that provides useful information for the correct implementation of an airport pavement management system (APMS) based on real-life data. Indeed, it permits comprehensive monitoring functions to be performed, based on the embedded sensing network.

Bisphenol A (BPA) is a synthetic phenol extensively used in the manufacture of polycarbonate plastics and epoxy resins and a component of liquid and food storages. Among health disorders potentially attributed to BPA, the effects on metabolism have been especially studied. BPA represents a hazard in prenatal life because of its presence in tissues and fluids during pregnancy. Our recent study in rats fed with BPA showed a placental increase in glucose type 1 transporter (GLUT-1), suggesting a higher uptake of glucose. However, the role of BPA on GLUT transporters in pregnant women with metabolic dysfunction has not yet been investigated. In this study, placental tissue from 26 overweight (OW) women and 32 age-matched normal weight (NW) pregnant women were examined for expression of GLUT1 and GLUT4. Placental explants from OW and NW mothers were exposed to BPA 1 nM and 1 μM and tested for GLUTs expression. The data showed a different response of placental explants to BPA in GLUT1 expression with an increase in NW mothers and a decrease in OW ones. GLUT4 expression was lower in the explants from OW than NW mothers, while no difference was showed between OW and NW in placental biopsies for any of the transporters.

In recent years, nanotechnology has sparked an interest in nanomodification of bituminous materials to increase the viscosity of asphalt binders and improves the rutting and fatigue resistance of asphalt mixtures. This paper presents the experimental results of laboratory tests on bituminous mixtures laid on a 1052 m-long test section built in Rome, Italy. Four asphalt mixtures for wearing and binder layer were considered: two polymer modified asphalt concretes (the former modified with the additive Superplast and the latter modified with styrene–butadiene–styrene), a “hard” graphene nanoplatelets (GNPs) modified asphalt concrete and a not-modified mixture. The indirect tensile strength, water sensitivity, stiffness modulus, and fatigue resistance of the mixtures were tested and compared. A statistical analysis based on the results has shown that the mixtures with GNPs have higher mechanical performances than the others: GNP could significantly improve the tested mechanical performances; further studies will be carried out to investigate its effect on rutting and skid resistance.

Although the design of jointed plain concrete pavements could be solved by commercial software, there is still a need for simple tools to be used in feasibility studies and preliminary cost–benefit analyses. This paper analyzed and verified jointed plain concrete pavements for airports composed of square slabs without tie and dowel bars. The examined slabs are laid on a cement-treated base layer and a stabilized granular subbase layer. The finite element software FAARFIELD was used to design the JPCP pavements when they are subjected to the design of the airplane (i.e., turboprop C-130J Hercules) under different conditions. Seven subgrade load bearing capacity values, twenty traffic levels, and two construction hypotheses (i.e., constant or variable thickness of the two deeper layers) were designed and then verified with the Westergaard theory in order to present a proposal for a catalogue. Finally, the construction cost per unit surface area was calculated for different construction methods of paving (by slip form paver or by fixed form). The obtained results provide a simple and fast procedure to design preliminary airport JPCPs.

Cycling for transportation is an important resource to reduce urban traffic congestion, enhance personal health, reduce energy consumption, and improve air quality, and the safety of cyclists in the cities is becoming a topic of growing interest. As shown in the literature, an important number of cyclist fatalities is due to road crashes occurring at urban intersections. This study combines a probabilistic and a damage model to perform a risk analysis for the collisions between motor vehicles and bicycles in the merging and diverging conflict points of a single-lane conventional roundabout with four arms, characterized by a permanent traffic flow. The probabilistic model is based on Poisson’s law and is aimed to measure the probability of a collision between bikes and motor vehicles within the elementary unit of exposure in each conflict point of the roundabout. The damage model exploits the reaction time of a road user to avoid a collision and has been built to develop a danger classification for the conflict points. The goal of this study is then to estimate the so-called risk of collision at the roundabout, to compare different possible layouts for various traffic volumes with increasing bike flows and geometric configurations, and to identify the most effective solutions to improve safety for cyclists. The results demonstrate the risk reduction given by a roundabike compared to a standard layout where cyclists and motor vehicles share the circulatory roadway. Therefore, the study here presented could help road managers to implement mitigation strategies taking into consideration both geometric and functional constraints.

At the international level, the interest in airport capacity is growing in the last years because its maximization ensures the best performances of the infrastructure. However, infrastructure, procedure, human factor constraints should be considered to ensure a safe and regular flow to the flights. This paper analyzed the airport capacity of an airport with two crossing runways. The fast time simulation allowed modeling the baseline scenario (current traffic volume and composition) and six operative scenarios; for each scenario, the traffic was increased until double the current volume. The obtained results in terms of average delay and throughput were analyzed to identify the best performing and operative layout and the most suitable to manage increasing hourly movements within the threshold delay of 10 min. The obtained results refer to the specific examined layout, and all input data were provided by the airport management body: the results are reliable, and the pursued approach could be implemented to different airports.

The attention to environmental impacts of cement production has grown fast in recent decades. The cement industry is a significant greenhouse gases emitter mainly due to the calcinations of raw materials and the combustions of fuels. This paper investigates on the environmental performances of cement production and on the identification of factors driving emissions. For this purpose, a sample of 193 different recipes of gray cement produced in Italy from 2014 to 2019 according to the European standard EN 197-1. This paper identifies the consumption impact categories (e.g., fossil fuels, renewable and non-renewable secondary fuels) that explain the assessment of the Global Warming Potential, one of the most crucial impacts of cement production. Having regard to the overall examined dataset and each cement type, a set of predictive models is implemented and evaluated. A similar approach has been adopted to produce accurate predictive models for further environmental impact categories that quantify emissions to air. The obtained results provide important information that can support cement producers to develop low-impacting cement recipes.

Comfort is a major requirement in planning pedestrian facilities. Pedestrians walk where they feel comfortable and when they do not feel at ease, they walk elsewhere. A typical example is that filthy, distressed, or too narrow sidewalks induce pedestrians to walk on carriageways. This behaviour jeopardizes road safety and highly dangerous to most users, leave them vulnerable. Unsuitable pavements can be the result of irregular maintenance operations to restore evenness after shock damage, weather phenomena, installation of equipment (e.g., posts, fences, urban furniture) with a reduction of walkable surface, or substandard repair work on pavements and patches due to emergency operations. These problems can be solved with an appropriate maintenance management system, which optimizes financial resources to make smart decisions about how to intervene with an adequate and lasting maintenance operation. This paper defines an evaluation index for sidewalk conditions as a part of an efficient set-up of a Sidewalk Management System, which is similar to the better known Road Management System. The study relies on surveys, as well as the classification and analysis of sidewalk distresses. The authors adapted an index already standardized by ASTM for roads and airports: the Pavement Condition Index (PCI). PCI has been modified to consider the specific types on the sidewalks studied within this paper. To validate the method, a case study of a residential district in Rome, Italy, was carried out. The chosen area lacks regular maintenance and has therefore resulted in a network of unsafe sidewalks. Frequent detour routes were surveyed and related to the level of distresses within a general assessment of safety. This study concentrates on sidewalks with flexible pavements because this type of pavement is the only one adopted in the survey areas and, in general, throughout Italy.

Endocrine-disrupting chemicals (EDCs) are exogenous substances able to mimic or to interfere with the endocrine system, thus altering key biological processes such as organ development, reproduction, immunity, metabolism and behavior. High concentrations of EDCs are found in several everyday products including plastic bottles and food containers and they could be easily absorbed by dietary intake. In recent years, considerable interest has been raised regarding the biological effects of EDCs, particularly Bisphenol A (BPA) and phthalates, on human pregnancy and fetal development. Several evidence obtained on in vitro and animal models as well as by epidemiologic and population studies strongly indicated that endocrine disruptors could negatively impact fetal and placental health by interfering with the embryonic developing epigenome, thus establishing disease paths into adulthood. Moreover, EDCs could cause and/or contribute to the onset of severe gestational conditions as Preeclampsia (PE), Fetal Growth Restriction (FGR) and gestational diabetes in pregnancy, as well as obesity, diabetes and cardiovascular complications in reproductive age. Therefore, despite contrasting data being present in the literature, endocrine disruptors must be considered as a therapeutic target. Future actions aimed at reducing or eliminating EDC exposure during the perinatal period are mandatory to guarantee pregnancy success and preserve fetal and adult health.

The aim of this paper is to present the results of X-ray diffraction (XRD) tests and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) analyses on a natural and lime-treated clay, in order to determine the percentage of lime able to stabilize soil. For this reason, XRD test analyses have been conducted on natural soil (TQ0) and on two different mixtures (TQ3 and TQ5): The former with 3% and the latter with 5% by mass of quicklime. These mixtures have been analyzed at different curing times: At the addition of lime (0 d), and after a mellowing period of 7 and 28 d. The obtained results show that 3% of CaO is the percentage of quicklime able to modify the material (initial consumption of lime (ICL)) and 5% of CaO is the percentage able to stabilize it (lime stabilization optimum (LSO)). Finally, SEM images allowed for the monitoring of the process of reactions between the soil and lime during the mellowing period, while EDS analyses validated the XRD results in terms of chemical composition of the examined soil. For the examined natural clay, statistical analysis of the obtained EDS results identified a linear regression curve between the added quicklime and the after-treatment Ca content. The proposed approach could be adopted to calculate the content of calcium after the treatment and verify the in situ-added CaO during roadworks or at the end of them.

Changes in weather patterns directly impact urban transport infrastructures. The increase in temperature and the ongoing precipitation changes should be handled and managed more frequently. In urban areas, most of the soil is impermeable and water hardly infiltrates into the subsoil. Permeable pavement is a technology that helps mitigate the effects of urban heat islands and surface impermeabilization. Porous concrete for pedestrian pavements ensures good structural, functional, and environmental performances. A pervious concrete mix differs from a conventional one in terms of the gradation of aggregates, namely, a lack of fine aggregates. The material porosity (on average 20%) causes compressive and flexural strengths lower than those of traditional concrete. The material is suitable for low-load pavements where the passage of motorized vehicles is forbidden or occasional. The pavement can be laid either monolithically or modularly, using two operating systems: returning water to underground aquifers and reducing runoff. The latter is the most frequently adopted in urban areas, where pedestrian and interdicted to motorized vehicle areas form a continuous and distributed network. In a common urban quarter, where 80% of the surface is impermeable, porous concrete pavements could cover up to 6% of the surface and provide architectural and aesthetic value for the environment.

In urban areas traffic-calming strategies and pedestrian friendly measures are often adopted to reduce the adverse impacts of motor vehicles on vulnerable users. This study surveyed 24 raised pedestrian crossings (RPCs) to examine their geometrical and functional characteristics. Geometric characteristics, location, administrative and effective vehicle speed, and the whole-body vibration acceleration induced to vehicle occupants while they are passing over, were considered. In addition to the analysis of the field data, geometrical and functional criteria to design RPCs were carried out. Particularly, two design approaches have been considered. In the first one, RPC provides a designated route across a carriageway raised to the same level, or close to the same level, as the sidewalks that provide access to the pedestrian crossing. In such condition, an RPC is not a traffic-calming device and its design should satisfy geometrical and comfort criteria for designing roads. The results from the surveys demonstrated that less than 10% of RPCs guarantee ride comfort. According to the second design approach, an RPC acts both as a marked pedestrian feature and as a traffic-calming device (i.e., it is trapezoidal in shape with sharp edges). The analysis of the vertical accelerations on vehicle occupants reveal that more than 90% of the surveyed RPCs comply with geometrical and dynamic criteria for speed tables. Extreme variations concerning the observed geometrical characteristics of RPCs and the modelled dynamic performances have been observed: It results in noneffective treatments. Therefore, the results of this study would contribute to providing geometric best practices for overcoming the regulation gap in this subject, and designing RPCs according to international standards.

The road safety of vulnerable users is a current issue; in densely populated areas, the use of alternative and light mobility vehicles is growing in popularity, and their users conflict with vehicles having larger dimensions and masses. This study focuses on the risk analysis of collision between bicyclists and motorized vehicles in urban intersections. Twenty-five urban four-leg intersections, with and without bike paths, were considered in order to identify the conflict points, calculate their hazardousness, and assess the risk of collision using a probabilistic approach. Traffic light setup, yield line retraction, design of areas, and counter-clockwise circulation reserved for bicyclists are the geometrical and functional approaches proposed to mitigate the risk of collision. Two risk-based approaches proposed by the authors were implemented—the first examines all identified conflict points, while the second assesses the risk condition of the overall intersection. The obtained results show that the number of conflict points varied between 32 and 112 and the risk of collision varied between 4.57 × 10−2 and 2.46 × 10−1. The proposed assessment allowed us to make an objective comparison between the possible layouts for various traffic mixes and design conditions, and to identify the most effective solutions. Significant differences in terms of risk were found. Each mitigation strategy should be motivated by a reasoned decision considering the different needs of all road users, traffic demand, and geometrical and functional constraints.

The attention to the most vulnerable road users has grown rapidly in recent decades. The experience gained reveals an important number of cyclist fatalities due to road crashes; most of which occur at intersections. In this study, dispersion of trajectories in urban intersections has been considered to identify the whole conflict area and the largest conflict areas between cars and bicycles, and the speeds have been used to calculate exposure time of cyclists and reaction time available to drivers to avoid collision. These data allow the summary approach to the problem, while a risk probability model has been developed to adopt an elementary approach analysis. A quantitative damage model has been proposed to classify each conflict point, and a probabilistic approach has been defined to consider the traffic volume and the elementary unit of exposure. The combination of damage and probability, permitted to assess the risk of crash, at the examined intersection. Three types of urban four-arm intersection, with and without bike paths, were considered. For each scheme, the authors assessed the risk of collision between the cyclist and the vehicle. The obtained results allowed the identification of the most hazardous maneuvers and highlighted that geometry and kinematics of traffic movements cannot be overlooked, when designing an urban road intersection. The strategy proposed by the authors could have a significant impact on the risk management of urban intersections. The obtained results and the proposed hazard estimation methodology could be used to design safer intersections.