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Highway bottlenecks are responsible for the majority of traffic congestion. Although the problem of bottleneck detection is not new, contemporary methods have not solved the problem thoroughly with regards to bottleneck locations, activation time, and related congestion tracking. These elements are essential for identifying and characterizing a bottleneck. This paper proposes a comprehensive framework for detecting and extracting these features of highway bottlenecks from traffic data. We particularly focus on questions (i) whether a bottleneck is the primary source of congestion or (ii) whether it is activated due to congestion caused by another downstream bottleneck. The underlying principles of the proposed method include the detection of congestion (in spatio-temporal patterns of traffic congestion), and the detection of speed discontinuities in traffic data (since this is an important indicator of a bottleneck activation). The method is data-driven and automatic therefore can be easily applied to different highways and used to obtain meaningful statistics of existing bottlenecks. We have tested the method on simulated data and also demonstrated it on real data from a busy highway section in the Netherlands. The results suggest that the method is robust to different implementations, i.e. locations, of loop-detectors which measure traffic at discrete locations.

CONTEXTE: La demande sans précédent de respirateurs N95 durant la pandémie de maladie à coronavirus 2019 (COVID-19) a entraîné une pénurie mondiale. Nous avons validé un protocole de décontamination rapide et économique répondant aux normes réglementaires afin de permettre la réutilisation sûre de ce type de masque. MÉTHODES: Nous avons contaminé 4 modèles courants de respirateurs N95 avec le coronavirus du syndrome respiratoire aigu sévère 2 (SRAS-CoV-2) et avons évalué l’inactivation virale après une désinfection de 60 minutes à 70 °C et à une humidité relative de 0 %. De même, nous avons étudié l’efficacité de la désinfection thermique, à une humidité relative allant de 0 % à 70 %, de masques contaminés à Escherichia coli. Enfin, nous avons examiné des masques soumis à de multiples cycles de désinfection thermique: nous avons évalué leur intégrité structurelle à l’aide d’un microscope à balayage, et leurs propriétés protectrices au moyen des normes du National Institute for Occupational Safety and Health des États-Unis relatives à la filtration particulaire, à la résistance respiratoire et à l’ajustement. RÉSULTATS: Une seule désinfection thermique a suffi pour que le SRAS-CoV-2 ne soit plus décelable sur les masques étudiés. En ce qui concerne les masques contaminés à E. coli, une culture de 24 heures a révélé que la bactérie n’était pratiquement plus décelable sur les masques désinfectés à 70 °C et à une humidité relative de 50 %, contrairement aux masques non désinfectés (densité optique à une longueur d’onde de 600 nm : 0,02 ± 0,02 contre 2,77 ± 0,09; p < 0,001), mais qu’elle persistait sur les masques traités à une humidité relative moindre. Les masques ayant subi 10 cycles de désinfection avaient toujours des fibres de diamètre semblable à celui des fibres des masques non traités, et ils répondaient encore aux normes d’ajustement, de filtration et de résistance respiratoire. INTERPRÉTATION: La désinfection thermique a réussi à décontaminer les respirateurs N95 sans compromettre leur intégrité structurelle ni modifier leurs propriétés. Elle pourrait se faire dans les hôpitaux et les établissements de soins de longue durée avec de l’équipement facilement accessible, ce qui réduirait la pénurie de N95.

BackgroundThe unprecedented demand and consequent global shortage of N95 respirators during the COVID-19 pandemic have left frontline workers vulnerable to infection. To potentially expand the supply, we validated a rapidly applicable low-cost decontamination protocol in compliance with regulatory standards to enable the safe reuse of personalized, disposable N95-respirators.MethodsFour common models of N95-respirators were disinfected for 60 minutes at 70°C either at 0% or 50% relative humidity (RH). Effective inactivation of SARS-CoV-2 and E. coli was evaluated in inoculated masks. The N95 filter integrity was examined with scanning electron microscopy. The protective function of disinfected N95 respirators was tested against US NIOSH standards for particle filtration efficiency, breathing resistance and respirator fit.ResultsA single heat treatment inactivated both SARS-CoV-2 (undetectable, detection limit: 100 TCID50/ml) and E. coli (0 colonies at 50%RH) in all four respirator models. Even N95-respirators that underwent ten decontamination cycles maintained their integrity and met US-governmental criteria for approval regarding fit, filtration efficiency and breathing resistance. Scanning electron microscopy demonstrated maintained N95 fiber diameter compared to baseline.InterpretationThermal disinfection enables large-scale, low cost decontamination of existing N95 respirators using commonly sourced equipment during the COVID-19 pandemic. This process could be used in hospitals and long term care facilities and also provides a feasible approach to expand the N95 supply in low- and middle-income regions.

Item does not contain fulltext As automated vehicles become increasingly common on the road, the call for an appropriate preparation for its drivers is becoming more urgent. Expert opinions and insights have been acquired via a focus group discussion with eleven Dutch driving examiners to assist in inventorying what types of preparations are needed. The concept of meaningful human control (MHC) as an integral part of the discussion lead to consensual findings regarding ADAS functionality and the drivers’ tasks, as well as discussion topics on driver training and levels of automation. It was concluded to have more research into human factors to safeguard proper control over automated vehicles. 2020 Forum on Integrated and Sustainable Transportation Systems (FISTS) (Delft, the Netherlands. 3-5 Nov. 2020)

New smart traffic signal control algorithms are capable of predicting the traffic signal state (red, green, or amber) changes, which can be provided to users to achieve more efficient traffic flow. However, these predictions pose an uncertain impact on the traffic flow and safety depending upon the quality of prediction. The information regarding the current state as well as the predicted residual time of state is communicated to other users in the form of Signal Phase and Timing (SPaT) data. In this paper, the SPaT message data is analyzed from an on-road pilot of different traffic signal control algorithms on provincial roads in the Province of North Holland. For analysis, new methods and indicators for quantification of prediction accuracy and quality of algorithm are proposed. These indicators can either be used for correction of state change prediction in real-time or for comparative analysis of the performance of different traffic signal control algorithms. This paper presents three main findings. First, it is found that a half fixed algorithm has very high prediction accuracy up to 99% for optimized directions. Second, the prediction accuracy of Time to Amber predictions improved by around 30% with this algorithm. Third, the overall reliability of prediction always increased with the use of the algorithm.

The inclusion of human factors (HF) in mathematical models is proving crucial to allow complex driving behaviour and interactions to be explicitly considered to capture driving phenomena. An important area where such integration is required is for the role of anticipation by drivers to compensate for critical traffic situations. In this paper, we introduce the concept of Anticipation Reliance (AR), which acts as a demand lowering compensative effect for the driving task by relying more on anticipation. We implement AR in a generic multi-scale microscopic traffic modelling and simulation framework to explore and explain the effects of HF on traffic operations and safety in critical traffic situations. This concept addresses a disparity in the description of driver workload in relation to the execution of driving tasks in regard to the confidence that drivers place on tasks that are sub-consciously catered for. The crossover from HF to a mathematical description of this role of AR introduces a ground-breaking concept that explains and models the mechanisms that allow drivers to compensate and avoid accidents in many circumstances, even when driving errors or sub-optimal driving performance occurs. By and large, the HF effects can be subdivided in effects on perception and anticipation; effects on sensitivity and response to stimuli; and effects on personal attributes and characteristics. A key aspect of the framework are two intertwined driver-specific mental state variables—total workload and awareness—that bridge between classic collision-free idealized models for lane changing and car following, and HF models that explain under which conditions the performance of drivers deteriorates in terms of reaction time, sensitivity to stimuli or other parameters. In this paper, we focus on the awareness construct, as described by AR, and explore the effects. We prove the effectiveness of the approach with a case example that demonstrates the ability of the model to dissect a complex traffic situation with both longitudinal and lateral driving tasks, while endogenously considering human factors and that produces accident avoidance and occurrence within the same order of magnitude compared to real traffic accident statistics.

Contains fulltext : 226739.pdf (Publisher’s version ) (Open Access) The future adoption of automated vehicles poses many challenges, with one of the more important being the preservation of control over vehicles that are no longer (fully) operated by drivers. There is consensus that vehicles should not perform actions that are unacceptable to humans. In this paper, we introduce the concept of Meaningful Human Control (MHC) as a function of a framework of the Automated Driving System (ADS). This framework is constructed through the core components that make up the ADS, primarily considered within the categories of the vehicle and driver. Identification of these components and the chain of control allow traceability of MHC to be performed, and aids vehicle manufacturers, software developers, other vehicle component designers, and vehicle- and driver licensing authorities to address many challenges related to the design and preservation of human control in automated vehicles. Operationalisation of MHC is discussed in the paper including a suggested approach that should aid understanding and the application of the concept. Four application examples are given and recommendations are made in regard to vehicle design, human machine interaction, transition of control, driver training, vehicle approval, and other topics. The framework and presented concept also allow researchers to identify areas to perform more explicit and relevant research and develop models that can be applied to perform projections of future impacts. 29 p.

It is becoming increasingly important to gain real-life insights into the effects of vehicle automation with the continued introduction of cooperative and automated vehicles (CAV). This study reports on the findings of a field operational test (FOT) of cooperative adaptive cruise control (CACC) vehicles on an arterial corridor with other traffic. The FOT demonstrated that that CACC vehicles can operate well under such conditions and can operate in platoons at lower time-headways than human driven vehicles. Platoon disengagement and cut-ins were analysed and showed that although many platoon break-ups are unavoidable, CACC operation was carried out without incident with frequent recoupling of platoons occurring. Most cut-ins occurred near to intersections, where vehicles are required to merge or need to change lanes to turn off the main corridor. It was not possible to derive potential traffic flow improvements from the FOT, due to a limited overall penetration rate and limitations of the intelligent traffic signals. The findings offer greater insights into the performance of CAV technology in a suburban environment and can aid road authorities to prepare infrastructure for the broader introduction of CAVs as well as the development of modelling tools to improve impact analysis of CAVs in urban environments.

Zusammenfassung Einleitung Die korrekte Diagnose und Lokalisation von peripheren Nervenläsionen ist essentiell für die Wahl der richtigen Therapie in der peripheren Nervenchirurgie. Vor allem Substanzdefekte müssen erkannt werden um eine frühe Wiederherstellung zu ermöglichen und Langzeitschäden zu verhindern. Neueste Entwicklungen in der MR-Neurographie können detaillierte Informationen über Morphologie und zukünftig möglicherweise sogar die Funktionalität eines Nervs in Relation zu umgebenden Strukturen liefern. In dieser Fallserie stellen wir Kasuistiken vor, die signifikant von einer erweiterten Diagnostik per MR-Neurographie profitierten. Methodik Wir zeigen den klinischen Verlauf von 5 exemplarischen Fällen, die sich mit traumatischen Nervenläsion vorstellten und mittels ergänzender MR-Neurographie einem konklusiven Therapiekonzept zugeführt wurden. Das Ausmaß der Schädigung sowie die Nervenintegrität wurden mittels speziell hochauflösender MR-Sequenzen evaluiert und mit den klinischen, z. T. intraoperativen, neurophysiologischen sowie sonographischen Befunden korreliert. Ergebnisse In zwei Fällen konnte trotz pathologischer Elektroneurographie und nicht eindeutigen Sonographiebefunden aufgrund der in der MR-Diagnostik erwiesenen Nervenintegrität erfolgreich eine konservative Therapie durchgeführt werden. In drei Fällen ermöglichte die MR-Neurographie die präzise Bestimmung von Art und Lokalisation der Nervenläsionen, sodass anschließend eine zielgerichtete Nervenrekonstruktion erfolgen konnte. Diskussion Obwohl noch keine systematischen klinischen Analysen vorliegen, konnten unsere Ergebnisse zeigen, dass die MR-Neurographie traumatische periphere Nervenläsionen korrekt diagnostizieren und lokalisieren kann. Hierdurch ermöglicht die MR-Neurographie eine verbesserte Diagnostik und somit Therapieplanung in der Nervenchirurgie. Das Risikoprofil ist identisch zu konventionellen MR-Untersuchungen, jedoch ist die Implementierung von notwendiger Hard- und Software sowie klinisch-radiologischer Expertise (noch) nicht flächendeckend verfügbar. Schlussfolgerung Die MR-Neurographie liefert entscheidende Informationen über die Art der Nervenläsion und kann somit die Notwendigkeit einer Operation sowie die passende OP-Strategie identifizieren.

The capacity drop forms a major reason why the prevention of congestion is targeted by traffic management, as lower capacities are detrimental to traffic throughput. Various reasons describing the dynamics behind the capacity have been described, however one of these, reaction times, has had less explicit attention when modelling on a macroscopic flow level. In this contribution, a method to include the effect of reaction times for the capacity drop in heterogeneous traffic is proposed. The applied method further overcomes difficulties in including reaction times in a discrete time model through relaxation of the updating process in the discretization. This approach is novel for application in the considered first order approach, which is practise ready, contrary to many other models that propose similar approaches. The combination of the introduced method and the model form a solid development and method to apply the capacity drop based on this causation of the capacity drop. The results of the experiment case showed that the influence of traffic heterogeneity had a limited effect on the severity of the capacity drop, while it did influence the time of congestion onset. The influence of the reaction time on traffic showed greater capacity drop values for greater reaction time settings. The findings showed the method effective and valid, while the model application is also practise ready. Keywords: Capacity drop, Traffic modelling, Heterogeneous traffic, Traffic flow

Nerve injury is often associated with limited axonal regeneration and thus leads to delayed or incomplete axonal reinnervation. As a consequence of slow nerve regeneration, target muscle function is often insufficient and leads to a lifelong burden. Recently, the diagnosis of nerve injuries has been improved and likewise surgical reconstruction has undergone significant developments. However, the problem of slow nerve regeneration has not been solved. In a recent meta-analysis, we have shown that the application of low-intensity ultrasound promotes nerve regeneration experimentally and thereby can improve functional outcomes. Here we want to demonstrate the experimental effect of low intensity ultrasound on nerve regeneration, the current state of investigations and its possible future clinical applications.

The practice of abdominal massage dates to years ago and associated with foetal and maternal morbidity and mortality when undertaken by untrained traditional birth attendants in our setting. We present a 30-year old G3P2+0 with uterine rupture and intra-uterine foetal death following abdominal massage. She was resuscitated and had emergency exploratory laparotomy and repair of uterine rupture.

Background: Gynaecological malignancies continue to be an important public health problem globally and are among the leading causes of morbidity and cancer-related deaths worldwide. In developing countries there is poor awareness and late presentation, and specialized cancer treatment centers are few, necessitating the gynaecologists at the tertiary hospitals to render surgical care for some cancer patients. The objective of the study was to determine the prevalence, indications, and surgical outcome of hysterectomy for primary gynaecological malignancies and assess the associated factors.Methods: This was a retrospective review of hysterectomies performed between March 2015 and February 2021. Data were obtained from operating theater and gynaecological ward records. Information on age, parity, indication, length of surgery, blood loss and any blood transfusion, post-operative complication, and mortality, were extracted. Data were analyzed using Statistical package for social sciences (SPSS) version 20.Results: Of 1240 major gynaecological surgeries, 26 were hysterectomies for malignant conditions giving a prevalence of 2.1%. Commonest indication was Endometrial cancer 16 (61.5%), followed by cervical cancer 3 (11.5%) and ovarian malignancy 3 (11.5%). There was a significant relationship between age (p=0.027) with the indications for hysterectomy. Commonest complication was anaemia 6 (23.1%) and wound sepsis 5 (19.2%). Anaemia was significantly associated with duration of surgery (p=0.004) and estimated blood loss (p=0.005).Conclusions: The prevalence of 2.1% for a non-cancer center is a fair contribution to efforts at caring for cancer patients. All surgeries were simple TAH±BSO and more than half were done for endometrial cancer. Further training of cancer surgeons and establishment of a Cancer Centre in the State is needed.

Uterine inversion is a rare clinical entity with challenging diagnosis and management. Reports of successfully managed cases contribute to knowledge and aid future management of cases among practitioners. We report a case of a 46 year old para-3 with protrusion of a mass from her vagina and vaginal bleeding of 7 days duration. She was managed as a case of chronic uterine inversion. She was resuscitated and had vaginal myomectomy, Haultin’s procedure and subsequently total abdominal hysterectomy due to ischaemic necrosis of parts of the uterus.