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This report proposes a generalized process for evaluating the ridership impact and traffic impact of a bus rapid transit system. The process proposed aims at providing such evaluation at the sketch planning stage and has a specific focus on two aspects -- the ridership forecast based on the implementation of various ITS technologies and the degradation of level of service that results from converting a traffic lane into exclusive bus lane for the implementation of a bus rapid transit system. The proposed process is tested on the Van Ness Blvd site in San Francisco, California. It is also implemented as a web-based toolbox that is easily accessible.

Bus Rapid Transit (BRT) systems with dedicated lanes have shown advantages over traditional bus systems and have attracted more transit riders. However, it is not always possible to build BRT systems with two dedicated lanes due to physical and cost constraints. A BRT system with a single dedicated lane is more practical and desirable in such situations. In a single lane configuration, buses approaching from opposite directions share the same road section and can overtake or pass each other only at the bus stops. We propose an optimization model to describe the synchronization requirements of the BRT buses with the objective to minimize the total travel and dwell time. The computational results show that a BRT system with a single dedicated lane yields similar total travel time to a BRT system with double dedicated lanes when the headway is not very short (e.g., more than 20 minutes). In addition, in order to manage the possible delay at intersections, a simple speed control algorithm is implemented to adjust the bus speed in real-time if the bus is delayed considerably. A microscopic simulation based on the simulation tool VISSIM is conducted to examine the impact of the BRT bus on other traffic and the performance of the speed control. The simulation result shows that the speed control effectively handles the delay at the intersection and that other traffic is rarely impacted by the speed control.

The symmetries and topological properties of the topological counterparts in 1D non‐Hermitian systems are investigated. It is found that, after applying the non‐unitary similarity transformation, the non‐unitary topological counterpart in real space exhibits completely different global symmetries except for the sublattice symmetry and reveals many brand new local symmetries. Due to the abundant symmetries of non‐unitary topological counterparts, it is also found that the unique overlapping projections about the unit sphere vector representing the eigenstates appear in the nontrivial regions, and the triviality of the point‐gap topology of non‐unitary topological counterpart completely eliminate the intrinsic skin effect in non‐Hermitian systems. It is also shown that the unitary topological counterpart never arises any changes for the original symmetries and topological structures even in real space. Unitary topological counterparts are further summarized about the two‐band Bloch Hamiltonian, which can expand the definition of non‐Bloch winding number. Furthermore, it is demonstrated theoretically that the Bloch Hamiltonian would still hold time‐reversal symmetry, abnormal particle‐hole symmetry, and sublattice symmetry even suffering from the non‐unitary transformation. This work provides a new way to understand the roles of symmetry and topology in non‐Hermitian systems from the perspective of topological counterparts. [ABSTRACT FROM AUTHOR]

Background: Hypoxia, a typical hallmark of solid tumors, exhibits an essential role in the progression of colorectal cancer (CRC), in which the dysregulation of long non-coding RNAs (lncRNAs) is frequently observed. However, the underlying mechanisms are not clearly defined. Methods: The TCGA database was analyzed to identify differential lncRNA expression involved in hypoxia-induced CRC progression. qRT-PCR was conducted to validate the upregulation of lncRNA STEAP3-AS1 in CRC cell lines and tumor-bearing mouse and zebrafish models under hypoxia. ChIP-qRT-PCR was used to detect the transcriptional activation of STEAP3-AS1 mediated by HIF-1α. RNA-seq, fluorescent in situ hybridization, RNA pulldown, RNA immunoprecipitation, co-immunoprecipitation, immunofluorescence and immunoblot experiments were used to ascertain the involved mechanisms. Functional assays were performed in both in vitro and in vivo models to investigate the regulatory role of STEAP3-AS1/STEAP3/Wnt/β-catenin axis in CRC proliferation and metastasis. Results: Here, we identified a hypoxia-induced antisense lncRNA STEAP3-AS1 that was highly expressed in clinical CRC tissues and positively correlated with poor prognosis of CRC patients. Upregulation of lncRNA STEAP3-AS1, which was induced by HIF-1α-mediated transcriptional activation, facilitated the proliferation and metastasis of CRC cells both in vitro and in vivo. Mechanistically, STEAP3-AS1 interacted competitively with the YTH domain-containing family protein 2 (YTHDF2), a N6-methyladenosine (m6A) reader, leading to the disassociation of YTHDF2 with STEAP3 mRNA. This effect protected STEAP3 mRNA from m6A-mediated degradation, enabling the high expression of STEAP3 protein and subsequent production of cellular ferrous iron (Fe2+). Increased Fe2+ levels elevated Ser 9 phosphorylation of glycogen synthase kinase 3 beta (GSK3β) and inhibited its kinase activity, thus releasing β-catenin for nuclear translocation and subsequent activation of Wnt signaling to support CRC progression. Conclusions: Taken together, our study highlights the mechanisms of lncRNA STEAP3-AS1 in facilitating CRC progression involving the STEAP3-AS1/STEAP3/Wnt/β-catenin axis, which may provide novel diagnostic biomarkers or therapeutic targets to benefit CRC treatment. Hypoxia-induced HIF-1α transcriptionally upregulates the expression of lncRNA STEAP3-AS1, which interacts competitively with YTHDF2, thus upregulating mRNA stability of STEAP3 and consequent STEAP3 protein expression. The enhanced STEAP3 expression results in production of cellular ferrous iron (Fe2+), which induces the Ser 9 phosphorylation and inactivation of GSK3β, releasing β-catenin for nuclear translocation and contributing to subsequent activation of Wnt signaling to promote CRC progression. [ABSTRACT FROM AUTHOR]

This paper considers a truck scheduling problem in the context of solid waste collection in the City of Porto Alegre, Brazil. The problem consists of designing 'good' daily truck schedules over a set of previously defined collection trips, on which the trucks collect solid waste in fixed routes and empty loads in one of several operational recycling facilities in the system. These facilities are managed by cooperatives whose members are poor and not part of the mainstream economy. The main objective is to minimize the total operating and fixed truck costs. We show that the problem can be modeled as a special case of the single-depot vehicle scheduling problem, which is polynomially solvable. However, due to the social benefits of the solid waste program, it is desirable to obtain balanced assignments of collection trips unloading their cargo at the recycling facilities. We prove that the truck scheduling problem considering balanced unloading is NP-hard. A heuristic approach, incorporating an auction algorithm and a dynamic penalty method, is designed to acquire a good solution. Finally, computational experiments are conducted on real data. The results show that the heuristic approach simultaneously reduces total costs and balances the number of trips assigned to each recycling facility. Keywords: Vehicle scheduling; Solid waste collection; Generalized assignment problem; Operations management, 1. Introduction Over the last few decades local authorities have devoted increasing attention to solid waste management due to its impact on the public concern for the environment. However, solid [...]