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Abstract Heavy traffic jams are difficult to predict due to the complexity of traffic dynamics. Understanding the network dynamics of traffic bottlenecks can help avoid critical large traffic jams and improve overall traffic conditions. Here, we develop a method to forecast heavy congestions based on their early propagation stage. Our framework follows the network propagation and dissipation of the traffic jams originated from a bottleneck emergence, growth, and its recovery and disappearance. Based on large-scale urban traffic-speed data, we find that dissipation duration of jams follows approximately power-law distributions, and typically, traffic jams dissolve nearly twice slower than their growth. Importantly, we find that the growth speed, even at the first 15 minutes of a jam, is highly correlated with the maximal size of the jam. Our methodology can be applied in urban traffic control systems to forecast heavy traffic bottlenecks and prevent them before they propagate to large network congestions.

Abstract The introduction of vehicle automation, shared mobility, and vehicle electrification will bring about changes in urban transportation, land use, energy, and the environment. The accurate estimation of these effects is therefore essential for sustainable urban development. However, existing research on estimating the energy and environmental effects of shared autonomous electric vehicles generally ignores the interaction between land-use and transportation systems. This study, therefore, analyzes the long-term effects of shared autonomous vehicles (SAVs) from the perspective of land use and transportation integration. Different SAV pricing scenarios are also developed to explore the optimal pricing strategy for low carbon–oriented SAVs. Moreover, the study has further assessed the effect of vehicle electrification on vehicle emissions and energy consumption. The results have shown a nonlinear relationship between SAV fares and their transportation, land-use, energy, and environmental effects. Under an appropriate pricing strategy, SAV deployment could reduce PM2.5 emission and energy consumption by 56–64% and 53–61%, respectively. With the further introduction of vehicle electrification, these can rise to 76% and 74%.

Background PFI-3 is a small-molecule inhibitor that targets the bromodomains (BRDs) of Brahma-related gene 1 (BRG1). This monomeric compound, which has high selectivity and potent cellular effects, has recently been developed. Although PFI-3 has been reported as a potential therapeutic agent targeting thrombomodulin, its role in the regulation of vascular function remains unknown. Therefore, we aimed to investigate the impact of PFI-3 on arterial vessel tone. Methods A microvascular tension measurement device (DMT) was utilized to identify alterations in vascular tension within the mesenteric artery. To detect variations in cytosolic [Ca2+]i, a Fluo-3/AM fluorescent probe and fluorescence microscope were employed. Additionally, whole-cell patch clamp techniques were utilized to evaluate the activity of L-type voltage-dependent calcium channels (VDCCs) in cultured arterial smooth muscle cells (A10 cells). Results PFI-3 exerted a dose-dependent relaxation effect on rat mesenteric arteries with both intact and denuded endothelium after phenylephrine (PE)- and high-K+-induced constriction. PFI-3-induced vasorelaxation was not affected by the presence of L-NAME/ODQ or K+ channel blockers (Gli/TEA). PFI-3 abolished Ca2+-induced contraction on endothelium-denuded mesenteric arteries preincubated by PE in Ca2+-free solution. Incubation with TG had no impact on PFI-3-induced vasorelaxation pre-contracted by PE. PFI-3 reduced Ca2+-induced contraction on endothelium-denuded mesenteric arteries pre-incubated by KCl (60 mM) in Ca2+-free solution. PFI-3 declined extracellular calcium influx in A10 cells detected by Fluo-3/AM fluorescent probe and fluorescence microscope. Furthermore, we observed that PFI-3 decreased the current densities of L-type VDCC by whole-cell patch clamp techniques. Conclusions PFI-3 blunted PE and high K+-induced vasoconstriction independent of endothelium on rat mesenteric artery. The vasodilatory effect of PFI-3 may be attributed to its inhibition of VDCCs and receptor-operated calcium channels (ROCCs) on vascular smooth muscle cells (VSMCs).

Abstract Novel coronavirus pneumonia (NCP) has been widely spread in China and several other countries. Early finding of this pneumonia from huge numbers of suspects gives clinicians a big challenge. The aim of the study was to develop a rapid screening model for early predicting NCP in a Zhejiang population, as well as its utility in other areas. A total of 880 participants who were initially suspected of NCP from January 17 to February 19 were included. Potential predictors were selected via stepwise logistic regression analysis. The model was established based on epidemiological features, clinical manifestations, white blood cell count, and pulmonary imaging changes, with the area under receiver operating characteristic (AUROC) curve of 0.920. At a cut-off value of 1.0, the model could determine NCP with a sensitivity of 85% and a specificity of 82.3%. We further developed a simplified model by combining the geographical regions and rounding the coefficients, with the AUROC of 0.909, as well as a model without epidemiological factors with the AUROC of 0.859. The study demonstrated that the screening model was a helpful and cost-effective tool for early predicting NCP and had great clinical significance given the high activity of NCP.

Systemic air embolism is a rare but potentially fatal complication related to many factors. The purpose of this article is to alert clinicians once patients occurs an abnormal neurological and cardiovascular status, following minor traumatic treatment, air embolism should be considered. A 20-year-old man who presented with fungal pneumonia with lung cavities formation was admitted to an intensive care unit (ICU) and received positive airway pressure ventilation. Four days later, the fungal pneumonia was improved, but the patient's blood pressure and arterial oxygen saturation deteriorated, so computed tomography (CT) scans were preformed to reevaluate him. The scans detected air embolism in the left atrium and ventricle, ascending aorta, aortic arch and its branches (right brachiocephalic, bilateral common carotid and right subclavian arteries), descending aorta and right coronary artery. A CT scan of the abdomen revealed air in the spleen, cauda pancreatic, superior mesenteric artery and right external iliac artery. The patient died two days later from multiple organ dysfunction. We suggest that vascular air embolism should be considered under mechanical ventilation when patients' neurologic and cardiovascular status deteriorates, and hyperbaric oxygen therapy should be conducted immediately. Keywords: Air embolism, Fungal pneumonia, Positive end-expiratory pressure

Atherosclerosis (AS) is a chronic inflammatory disease characterized by accumulating deposition of lipids in the arterial intima. Notably, macrophages participate centrally in the pathogenesis of this deadly disease. In this study, we established AS mouse models in order to investigate the effect of microRNA-133b (miR-133b) on vulnerable plaque formation and vascular remodeling in AS and explore the potential functional mechanisms. The expression of miR-133b was altered or the Notch-signaling pathway was blocked in the AS mouse models in order to evaluate the proliferation, migration, and apoptosis of macrophages. It was observed that miR-133b was upregulated in AS, which might target MAML1 to regulate the Notch-signaling pathway. AS mice with downregulated miR-133b or inhibited Notch-signaling pathway presented with a reduced AS plaque area, a decreased positive rate of macrophages, and an increased positive rate of vascular smooth muscle cells. Moreover, Notch-signaling pathway blockade or miR-133b downregulation inhibited the macrophage viability and migration and accelerated the apoptosis. This study provides evidence that downregulated miR-133b expression may inhibit the immune responses of macrophages and attenuate the vulnerable plaque formation and vascular remodeling in AS mice through the MAML1-mediated Notch-signaling pathway, highlighting miR-133b as a novel therapeutic target for AS. Keywords: microRNA-133b, atherosclerosis, Notch-signaling pathway, macrophage, plaque formation

Most route choice models assume that people are completely rational. Recently, regret theory has attracted researchers’ attentions because of its power to depict real travel behavior. This paper proposes a multiclass stochastic user equilibrium assignment model by using regret theory. All users are differentiated by their own regret aversion. The route travel disutility for users of each class is defined as a linear combination of the travel time and anticipated regret. The proposed model is formulated as a variational inequality problem and solved by using the self-regulated averaging method. The numerical results show that users’ regret aversion indeed influences their route choice behavior and that users with high regret aversion are more inclined to change route choice when the traffic congestion degree varies. Keywords: Traffic, Stochastic user equilibrium, Regret aversion, User heterogeneity, Route choice

In light of the increasing demand for passenger transportation on high-speed railway (HSR), the pedestrian flow at HSR stations has become quite crowded in many countries, which has attracted researchers to study the HSR boarding behavior. In this paper, we propose three boarding strategies based on the features of the boarding behavior at an origin HSR station; we then use a cellular automaton (CA) model to study the impacts of boarding strategies on each passenger’s motion during the boarding process at HSR station. The simulation results indicate that some of the three strategies can optimize some passengers’ boarding time and relieve the congestion degree, and the positive impacts on the boarding process are the most prominent when the three strategies are used simultaneously. The results can help administrators to effectively organize the boarding process at the origin HSR station.

For an elastic demand transportation network with continuously distributed value of time, the system disutility can be measured either in time units or in cost units. The user equilibrium model and the system optimization model are each formulated in two different criteria. The conditions required for making the system optimum link flow pattern equivalent to the user equilibrium link flow pattern are derived. Furthermore, a bi-objective model has been developed which minimizes simultaneously the system travel time and the system travel cost. The existence of a pricing scheme with anonymous link tolls which can decentralize a Pareto system optimum into the user equilibrium has been investigated.

This article proposes a tradable credit scheme for managing commuters’ travel choices. The scheme considers bottleneck congestion and modal split in a competitive highway–transit network with heterogeneous commuters who are distinguished by their valuation of travel time. The scheme charges all auto travelers who pass the bottleneck during a peak-time window in the form of mobility credits. Those who avoid the peak-time window, by either traveling outside the peak-time window or switching to the transit mode, may be rewarded credits. An artificial market is created so that the travelers may trade these credits with each other. We formulate the credit price and the rewarded and charged credits under tradable credit scheme. Our analyses indicate that the optimal tradable credit scheme can achieve nearly 40% efficiency gains depending on the level of commuters’ heterogeneity. In addition, this scheme distributes the benefits among all the commuters directly through the credit trading. Our results suggest that in assessing the efficiency of tradable credit scheme, it is important to take into account the commuters’ heterogeneity. Numerical experiments are conducted to examine the sensitivity of tradable credit scheme designs to various system parameters.

This paper investigates the efficiency loss of selfish routing simultaneously with user equilibrium (UE) player and Cournot-Nash (CN) players. The upper bound of the efficiency loss of UE-CN mixed equilibrium with polynomial cost functions is obtained by the scaling method and the nonlinear programming method, respectively. It is shown that the upper bound of efficiency loss obtained by the scaling method only depends on the polynomial degree of the link travel cost function and the upper bound of efficiency loss obtained by the nonlinear programming method depends on the number of the CN players besides the aforementioned factors. The numerical tests validate our analytical results. KEY WORDS: efficiency loss, UE-CN mixed equilibrium, variational inequality, selfish routing game

The cost-based system optimum problem in networks with continuously distributed value of time is formulated as a path-based form, which cannot be solved by the Frank-Wolfe algorithm. In light of magnitude improvement in the availability of computer memory in recent years, path-based algorithms have been regarded as a viable approach for traffic assignment problems with reasonably large network sizes. We develop a path-based gradient projection algorithm for solving the cost-based system optimum model, based on Goldstein-Levitin-Polyak method which has been successfully applied to solve standard user equilibrium and system optimum problems. The Sioux Falls network tested is used to verify the effectiveness of the algorithm.

In most of transportation literature, users are assumed to be perfectly rational in minimizing their own travel costs or perceived travel costs. However, users may not be perfectly rational in implementing their choices in reality. There exists a kind of boundedly rational users, that is, oblivious users. These oblivious users make their route choices by simple criteria, for example, selecting the shortest (or the most direct) route only based on physical distance or simply following routes recommended by a GPS system. This paper investigates how the existence of oblivious users affects the equilibrium bus line choice behavior in a public transit system. And we propose a method to design a more realistic system.

Liver disease can develop in chronic hepatitis B (CHB) patients with normal or mildly elevated alanine aminotransferase (ALT) who seldom undergo liver biopsy. We aimed to determine histologic characteristics of a large cohort of Chinese CHB patients undergoing liver biopsy and to evaluate the utility of ALT and HBV DNA values at the time of biopsy in predicting liver disease in this population. This prospective study enrolled 230 treatment-naïve patients with persistently normal or mildly elevated ALT. All patients had a liver biopsy. ALT, aspartate aminotransferase (AST), and HBV DNA levels were some of the other parameters measured. Using Scheuer's classification, significant histology was defined as stage ≧2 fibrosis and/or stage 1 fibrosis plus≧ grade 2 inflammation. Liver disease was observed in 34.4% and 61.8% of patients with normal ALT and mildly elevated ALT, respectively. Patients with mildly elevated ALT levels had significantly more events, including liver disease, elevated AST, and moderate to severe inflammation and liver fibrosis, than patients with normal ALT (all P≤0.005). A total of 107 patients (46.5%) had liver disease and 123 (53.5%) did not. PLT and ALT were significantly associated with liver disease (both P