Modeling Environmental Operative Elements in Agent-Based Pedestrian Simulation

Models for pedestrian simulation are employed on a day-to-day basis for supporting the design and planning of the built environment in normal and evacuation situations. One of the aspects that are least investigated in the community, probably because it is considered closer to technology transfer than to research, is the modelling of operational elements of the simulated environment. The present paper briefly describes an agent-based approach to the representation of operative elements of the environment with particular attention to the mechanisms of interaction between these active objects and pedestrians

Lane Formation Beyond Intuition Towards an Automated Characterization of Lanes in Counter-flows

Pedestrian behavioural dynamics have been growingly investigated by means of (semi)automated computing techniques for almost two decades, exploiting advancements on computing power, sensor accuracy and availability, computer vision algorithms. This has led to a unique consensus on the existence of significant difference between unidirectional and bidirectional flows of pedestrians, where the phenomenon of lane formation seems to play a major role. The collective behaviour of lane formation emerges in condition of variable density and due to a self-organisation dynamic, for which pedestrians are induced to walk following preceding persons to avoid and minimize conflictual situations. Although the formation of lanes is a well-known phenomenon in this field of study, there is still a lack of methods offering the possibility to provide an (even semi-) automatic identification and a quantitative characterization. In this context, the paper proposes an unsupervised learning approach for an automatic detection of lanes in multi-directional pedestrian flows, based on the DBSCAN clustering algorithm. The reliability of the approach is evaluated through an inter-rater agreement test between the results achieved by a human coder and by the algorithm

Assessing the Role of Counterion in Gold-Catalyzed Dearomatization of Indoles with Allenamides by NMR Studies

The counterion effect in the gold(I)-catalyzed dearomative condensation of indoles with allenamides is unveiled by means of 1D- and 2D-NMR investigation. The different coordination ability and hydrogen bonding tendency of TFA– and OTf– led to specific interactions with the reaction partners dictating the regiodivergent outcome

Calibration and validation of a simulation model for predicting pedestrian fatalities at unsignalized crosswalks by means of statistical traffic data

This work presents a simulation model for unsignalized crosswalks which takes into account collisions between vehicles and pedestrians, thus allowing to assess the estimated yearly pedestrian fatality. In particular, we focus on a method to calibrate such a model combining measurable crosswalk characteristics, such as maximum speed limit or drivers' compliance, with statistical data for past accidents obtained from local municipality. In order to perform simulations under realistic conditions, we constructed a one-week scenario where pedestrian and vehicle traffic vary using specific patterns each hour of the week. The constructed traffic profile is based on openly available data and the suitability for the scenario considered (a crosswalk in Milan, Italy) is investigated showing that cultural/lifestyle elements determine the variation of weekly traffic. Simulations using the constructed one-week scenario were used to obtain the only non-measurable parameter which account for pedestrians' and drivers' distraction. In addition, we also focused on the presence of elderly pedestrians which have different physiological characteristics compared to adults or children and are becoming an important part of the population in several countries around the globe. The simulation model presented here and the method suggested for calibration may be employed in different contexts, thus allowing to build an important tool to be used not only for transportation efficiency/optimization but also for safety analysis. Keywords: Traffic simulation, Accident prevention, Unsignalized crosswalk, Vehicle-pedestrian interaction, Weekly traffic variatio

Cocaine detrimentally affects mitochondrial functionality and cell viability in dopaminergic neurons.

An elevated consumption of cocaine (benzoylmethylecgonine), which causes anesthetic and stimulant effects on the central nervous system, may be associated with several neurodegenerative conditions affecting dopaminergic neurons, such as Parkinson's disease (PD). To investigate the impact of cocaine on cell viability and morphology, dopaminergic neurons from the substantia nigra (SN4741) were cultured. Analysis involved assessing cell death (LDH levels) and cell morphology (GIEMSA staining) after a 24-hour treatment period. Additionally, the effects on reactive oxygen species (ROS) generation (DH2), membrane potential (JC-1), oxygen consumption rate (OCR), and mitochondrial stress (Seahorse) were evaluated after a 6-hour treatment. The optimal concentration of cocaine for experimental use (2 mM) was identified, inducing a substantial 39.75% neuronal death. Examination of neuronal death (LDH) revealed a remarkable 280% increase following cocaine treatment. Optical analysis demonstrated heightened mortality and detrimental changes in neuronal morphology post-cocaine treatment, including a globose shape, loss of synapses, extremely thin membrane, and cell aggregation. In the "short time" experiments, mitochondrial oxidative damage was evident in SN cells treated with cocaine, leading to the demise of 75% of the cells. Furthermore, a significant 173.6% increase in reactive oxygen species (ROS) production and a 20% reduction in mitochondrial membrane potential (JC-1 assay) were observed. Cocaine treatment also resulted in a notable 60% decrease in mitochondrial oxygen consumption. In summary, a concentration of 2 mM cocaine induces a considerable rise in mitochondrial oxidative damage, subsequently causing morphological alterations and progressive death of dopaminergic neurons due to the accumulation of reactive oxygen species (ROS).Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

The still under-investigated role of cognitive deficits in PML diagnosis

Background: Despite cognitive deficits frequently represent the first clinical manifestations of Progressive Multifocal Leukoencephalopathy (PML) in Natalizumab-treated MS patients, the importance of cognitive deficits in PML diagnosis is still under-investigated. The aim of the current study is to investigate the cognitive deficits at PML diagnosis in a group of Italian patients with PML. Methods: Thirty-four PML patients were included in the study. The demographic and clinical data, the lesion load and localization, and the longitudinal clinical course was compared between patients with (n = 13) and without (n = 15) cognitive deficit upon PML suspicion (the remaining six patients were asymptomatic). Clinical presentation of cognitive symptoms was described in detail. Result: After symptoms detection, the time to diagnosis resulted to be shorter for patients presenting with cognitive than for patients with non cognitive onset (p = 0.03). Within patients with cognitive onset, six patients were presenting with language and/or reading difficulties (46.15%); five patients with memory difficulties (38.4%); three patients with apraxia (23.1%); two patients with disorientation (15.3%); two patients with neglect (15.3%); one patients with object agnosia (7.7%), one patient with perseveration (7.7%) and one patient with dementia (7.7%). Frontal lesions were less frequent (p = 0.03), whereas temporal lesions were slightly more frequent (p = 0.06) in patients with cognitive deficits. The longitudinal PML course seemed to be more severe in cognitive than in non cognitive patients (F = 2.73, p = 0.03), but differences disappeared (F = 1.24, p = 0.29) when balancing for the incidence of immune reconstitution syndrome and for other treatments for PML (steroids, plasma exchange (PLEX) and other therapies (Mefloquine, Mirtazapine, Maraviroc). Conclusion: Cognitive deficits at PML onset manifest with symptoms which are absolutely rare in MS. Their appearance in MS patients should strongly suggest PML. Clinicians should be sensitive to the importance of formal neuropsychological evaluation, with particular focus on executive function, which are not easily detected without a formal assessment