The Potential of Ridesharing Adoption and its Effects on CO2 Emissions and Customer Experience

Taxi services are an integral part of urban transport and are a major contributor to air pollution and traffic congestion, which adversely affect human life and health. Sharing taxi rides is one way to reduce the unfavorable effects of cab services on cities. However, this comes at the expense of passenger discomfort, quantified in terms of longer travel times. Taxi ridesharing is a sophisticated mode of urban transport that combines individual trip requests with similar spatiotemporal characteristics into a shared ride. We propose a one-to-one sharing strategy that pairs trips with similar starting and ending points. We examine the method using an open dataset with trip information on over 165 million taxi rides. We show that the cumulative journey time can be reduced by 48 percent while maintaining a relatively low level of passenger inconvenience, with a total average delay compared to an individual mobility case of 6 minutes and 42 seconds. This advantage is accompanied by decreases in emissions of 20.129 tons on an ordinary day and a potential fare reduction of 49 percent, which could point to a widespread passenger acceptance of shared taxi services. Overall, a matching rate of 13 percent is reached while a 27 percent matching rate is attained for high-demand areas. Compared to many-to-many sharing dynamic routing methodologies, our scheme is easier to implement and operate, making fewer assumptions about data availability and customer acceptance

A Taxonomy of Platform Envelopment: Revealing Patterns and Particularities

Platform envelopment describes a competitive move whereby a digital platform enters an adjacent market. On one hand, it might enable to dethrone an established platform. On the other hand, it might give rise to the creation of platform conglomerates, which increases the concentration of private power. Therefore, platform envelopment has recently attracted significant attention from regulators and scholars. However, the traditional view of platform envelopment does not consider recent platform envelopment practices observed in research and practice. In this study, we aim to determine and structure the complexity of platform envelopment. We investigated 20 cases and developed a taxonomy of platform envelopment. We further encoded these cases into the comprehensive taxonomy and derived platform envelopment patterns and particularities. Our work contributes to research by establishing a foundation for the conceptual understanding of platform envelopment. Regulators can use this taxonomy to classify platform envelopment cases and determine potentially anti-competitive conduct

Axis-Parallel Right Angle Crossing Graphs

A RAC graph is one admitting a RAC drawing, that is, a polyline drawing in which each crossing occurs at a right angle. Originally motivated by psychological studies on readability of graph layouts, RAC graphs form one of the most prominent graph classes in beyond planarity. In this work, we study a subclass of RAC graphs, called axis-parallel RAC (or apRAC, for short), that restricts the crossings to pairs of axis-parallel edge-segments. apRAC drawings combine the readability of planar drawings with the clarity of (non-planar) orthogonal drawings. We consider these graphs both with and without bends. Our contribution is as follows: (i) We study inclusion relationships between apRAC and traditional RAC graphs. (ii) We establish bounds on the edge density of apRAC graphs. (iii) We show that every graph with maximum degree 8 is 2-bend apRAC and give a linear time drawing algorithm. Some of our results on apRAC graphs also improve the state of the art for general RAC graphs. We conclude our work with a list of open questions and a discussion of a natural generalization of the apRAC model

Axis-Parallel Right Angle Crossing Graphs

A RAC graph is one admitting a RAC drawing, that is, a polyline drawing in which each crossing occurs at a right angle. Originally motivated by psychological studies on readability of graph layouts, RAC graphs form one of the most prominent graph classes in beyond planarity. In this work, we study a subclass of RAC graphs, called axis-parallel RAC (or apRAC, for short), that restricts the crossings to pairs of axis-parallel edge-segments. apRAC drawings combine the readability of planar drawings with the clarity of (non-planar) orthogonal drawings. We consider these graphs both with and without bends. Our contribution is as follows: (i) We study inclusion relationships between apRAC and traditional RAC graphs. (ii) We establish bounds on the edge density of apRAC graphs. (iii) We show that every graph with maximum degree 8 is 2-bend apRAC and give a linear time drawing algorithm. Some of our results on apRAC graphs also improve the state of the art for general RAC graphs. We conclude our work with a list of open questions and a discussion of a natural generalization of the apRAC model

Response to primary chemoradiotherapy of locally advanced oropharyngeal carcinoma is determined by the degree of cytotoxic T cell infiltration within tumor cell aggregates

BackgroundEffective anti-tumor immune responses are mediated by T cells and require organized, spatially coordinated interactions within the tumor microenvironment (TME). Understanding coordinated T-cell-behavior and deciphering mechanisms of radiotherapy resistance mediated by tumor stem cells will advance risk stratification of oropharyngeal cancer (OPSCC) patients treated with primary chemoradiotherapy (RCTx).MethodsTo determine the role of CD8 T cells (CTL) and tumor stem cells for response to RCTx, we employed multiplex immunofluorescence stains on pre-treatment biopsy specimens from 86 advanced OPSCC patients and correlated these quantitative data with clinical parameters. Multiplex stains were analyzed at the single-cell level using QuPath and spatial coordination of immune cells within the TME was explored using the R-package Spatstat.ResultsOur observations demonstrate that a strong CTL-infiltration into the epithelial tumor compartment (HR for overall survival, OS: 0.35; p<0.001) and the expression of PD-L1 on CTL (HR: 0.36; p<0.001) were both associated with a significantly better response and survival upon RCTx. As expected, p16 expression was a strong predictor of improved OS (HR: 0.38; p=0.002) and correlated with overall CTL infiltration (r: 0.358, p<0.001). By contrast, tumor cell proliferative activity, expression of the tumor stem cell marker CD271 and overall CTL infiltration, regardless of the affected compartment, were not associated with response or survival.ConclusionIn this study, we could demonstrate the clinical relevance of the spatial organization and the phenotype of CD8 T cells within the TME. In particular, we found that the infiltration of CD8 T cells specifically into the tumor cell compartment was an independent predictive marker for response to chemoradiotherapy, which was strongly associated with p16 expression. Meanwhile, tumor cell proliferation and the expression of stem cell markers showed no independent prognostic effect for patients with primary RCTx and thus requires further study

Anisotropic topographies restore endothelial monolayer integrity and promote the proliferation of senescent endothelial cells

Thrombogenicity remains a major issue in cardiovascular implants (CVIs). Complete surficial coverage of CVIs by a monolayer of endothelial cells (ECs) prior to implantation represents a promising strategy but is hampered by the overall logistical complexity and the high number of cells required. Consequently, extensive cell expansion is necessary, which may eventually lead to replicative senescence. Considering that micro-structured surfaces with anisotropic topography may promote endothelialization, we investigated the impact of gratings on the biomechanical properties and the replicative capacity of senescent ECs. After cultivation on gridded surfaces, the cells showed significant improvements in terms of adherens junction integrity, cell elongation, and orientation of the actin filaments, as well as enhanced yes-associated protein nuclear translocation and cell proliferation. Our data therefore suggest that micro-structured surfaces with anisotropic topographies may improve long-term endothelialization of CVIs. Keywords: aging; anisotropy; endothelial cells; monolayer integrity; proliferation; senescence; telomere; topograph