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Background: Phthalates may disturb metabolic homeostasis in the liver by interfering with the peroxisome proliferator-activated receptors (PPARs). However, the role of hepatic macrophages in the lipid metabolic dysregulation induced by diethylhexyl phthalate (DEHP) remains unclear. Objectives: We aimed to evaluate the respective role of hepatocyte- and macrophage-specific PPAR[gamma] in the hepatotoxicity induced by DEHP. Methods: Wild-type (WT), hepatocyte-specific PPAR[gamma] knockout (Hep-KO), and macrophage-specific PPAR knockout (Mac-KO) mice were administered DEHP (625 mg/kg body weight) by daily gavage for 28 d, followed by hepatotoxicity examination and macrophage analysis. RNA sequencing and lipid metabolomic analysis were used to characterize the molecular changes in mouse liver. Mouse bone marrowderived macrophages (BMDMs) and human monocytic THP-1 cell-derived macrophages were used to investigate the mechanistic regulation of macrophages' polarization by DEHP and mono(2-ethylhexyl) phthalate (MEHP). Results: The levels of hepatic steatosis and triglyceride were significantly higher in the mice treated with DEHP compared with the control mice in the WT and Hep-KO model. Lipid accumulation induced by DEHP was notably attenuated in the Mac-KO mice, but M2-polarization of hepatic macrophages in the Mac-KO mice was significantly higher compared with the WT mice under DEHP treatment. The M2-polarization of BMDMs and human macrophages was suppressed by DEHP and MEHP. Transcriptomic and lipidomic data suggested lower levels of lipid biosynthesis, fatty acid oxidation, and oxidative phosphorylation in the Mac-KO mice compared with the WT and Hep-KO mice under DEHP treatment. Conclusions: Our data suggested that the orchestrated activation of PPAR[alpha] and PPAR[gamma] by MEHP may reprogram hepatic macrophages' polarization, thereby affecting lipid homeostasis in the mouse liver. Although this conclusion was based on studies conducted in mice and in vitro, these findings may aid in elucidating the health effect of environmental phthalate exposure. https://doi.org/10.1289/EHP9373, Introduction Phthalates are widely used as industrial plasticizers in the manufacture of plastics, resins, rubbers, paints, emulsifiers, medical devices, personal care products, and so on. Diethylhexyl phthalate (DEHP) is the [...]

The Efficient Deployment of Advanced Public Transportation Systems (EDAPTS) demonstration at California State Polytechnic University, Pomona assessed the viability of using the EDAPTS procurement, installation, verification, and validation processes in a small transit environment to reduce the cost of ownership for technology solutions. Modified Systems Engineering processes were used to deploy an Intelligent Transportation System (ITS) solution on the Cal Poly Pomona Bronco Express campus bus system. This report provides a summary of methodologies used, outcomes, findings, recommendations and lessons learned stemming from the demonstration.The report explains the use of a modified version of the Federal Highway Administration (FHWA) Systems Engineering “V-model” that helped the research team and stakeholders coalesce with a common understanding of expectations of what the procured system needed to do. The EDAPTS procurement process used by Bronco Express demonstrated a practical procurement and bidding methodology useful to small and medium transit agencies when acquiring ITS solutions. It also summarizes procedures that are effective for installing and testing lower-cost ITS systems and provides a practical methodology for verifying and validating them. Lastly, it compares the results with the original user needs and the performance specifications requested in the Bronco Express EDAPTS RFP.

The California Department of Transportation (Caltrans) and the Federal Transit Administration (FTA) embarked on a research program entitled “Efficient Deployment of Advanced Public Transportation Systems” (EDAPTS) in the late 1990’s. The Bronco Express EDAPTS Stage 5 Deployment Demonstrationproject at California State Polytechnic University, Pomona (Cal Poly Pomona) is an integral part of this program. Its objective is to go through the procurement and deployment process of a low cost Intelligent Transportation Systems (ITS) solution to determine if the EDAPTS concepts are optimized for small transit agencies and if they can be successfully transitioned to the commercial marketplace.This report documents the installation, verification, and validation steps associated with the Bronco Express EDAPTS Demonstration project. It identifies and summarizes procedures that are effective in installing and testing a lower-cost ITS system and provides a practical methodology for verifying and validating small transit ITS systems. It also documents outcomes of the installed system in compliance with the user needs and the performance specifications as requested in the Bronco Express EDAPTS RFP.

This report documents the Bronco Express EDAPTS System procurement process that follows the V-Model. The V-model process led the research team to have a clear understanding of expectations of what the procured system needed to do. It demonstrated a practical procurement and bidding methodology for small/medium transit agencies to acquire their own unique EDAPTS solutions.The procurement was conducted in two phases: 1) the pre-procurement evaluation and definition processes and 2) the Request for Proposal (RFP) process. In the pre-procurement process, the EDAPTS Operations Guidelines that described the most valued system characteristics through the use of scored operational scenarios was developed. The guidelines helped the research team identify the high-priority operational needs and wants that were eventually incorporated in the RFP document.The RFP process involved the RFP document development and the selection of a winning contractor. The RFP document development incorporated findings from the pre-procurement process. The selection of the winning contractor was a systematic, unbiased process based on the criteria pre-established in the RFP document.

This study addresses the benefits and costs of Advanced Public Transportation Systems (APTS) applications in small and medium sized transit agencies using the research test implementation of a small transit oriented Intelligent Transportation System (ITS) on San Luis Obispo Transit as a case study. The Smart Transit System at San Luis Obispo is in a pre-commercialized state and implements the Efficient Development of Advanced Public Transportation Systems (EDAPTS) framework concept (Gerfen, 2001). The system has many potential benefits that will be identified and evaluated from a cost of service standpoint. The supporting hypothesis of this research is that small transit properties will be encouraged to deploy the EDAPTS ITS framework concept if the San Luis Obispo Smart Transit System can be shown to have a viable benefit-cost ratio.In order to deploy ITS applications, transit properties typically look for benefits and costs information about the services they are considering as well as documented lessons learned from the experiences of others. To be most effective, these inputs should be supplemented with information that describes the context from which the data were derived.Since the implementation of this EDAPTS Smart Transit System in 2001, only limited data analysis has been undertaken to evaluate the benefits of the system to riders, operators and the Cal Poly SLO community. A complete benefit-cost analysis is needed to provide small or medium sized transit properties with the economic justification of the EDAPTS framework deployment.This paper documents the literature review undertaken to summarize past work on evaluation of similar APTS applications and to identify and assess the analytic methods and tools available for the complete benefit-cost evaluation of SLO Transit Smart Transit System.

This technical report summarizes the benefit/cost evaluation of the SLO Transit EDAPTS ITS system. It provides a detailed description of the methodologies and procedures used, as well as the research findings resulting from the evaluation effort. Using passenger questionnaire, boarding time surveys and interviews with SLO Transit drivers and administrators, the research team collected and estimated various benefits and costs of the SLO Transit EDAPTS system and conducted a benefit/cost (B/C) ratio analysis on the EDAPTS system. Also the research team performed a sensitivity analysis of B/C ratios to different discount rates and service lives of the EDAPTS system. The ratios of annual benefits to annual costs are at least 3.9:1 for the SLO Transit EDAPT ITS system. This strongly indicates that the EDAPTS ITS technologies are economically viable.

Efficient Deployment of Advanced Public Transportation Systems (EDAPTS) Smart Transit System was developed by California Polytechnic State University, San Luis Obispo in a previous research effort from 1997 to 2007. California Partners for Advanced Transit and Highways (PATH) and the California Department of Transportation (Caltrans) have sponsored follow-on research to develop performance-based specifications for the EDAPTS system. These specifications are intended to facilitate industry adoption and widespread deployment of EDAPTS transit management system. The EDAPTS Performance Specification was developed by reviewing industry performance specification best practices, identifying all unique EDAPTS elements, determining appropriate performance metrics for each element, and determining these performance metrics. All EDAPTS elements and their associated performance metrics were organized and imported into a database for ease of analysis and automated performance specification report generation. An EDAPTS data-formatting standard was developed in conjunction with performance specification development efforts. The data-formatting standard is required to ensure that various parts of EDAPTS will be able to be procured from vendors as a commodity with ensured interoperability in the future. The non-proprietary EDAPTS performance specification and its supporting database program are available for general use by transit operators, service provides, and transit management system providers.

This report documents the outcomes of the February 6, 2007 workshop. It presents the most valued system characteristics of the Bronco Express EDAPTS system through the use of scored operational scenarios. The operational scenarios included in this report are down selected from those described in the initial release (V3.0) of the Operations Description report. The Advisory Panel members considered only scenarios with medium or high priority to be worthy of final consideration as deployable elements. These selected scenarios will allow the researchers to have an overall understanding of how the system will need to function in daily activities, better characterize the benefits that will be realized, and define any limitations that will have to be accommodated when the system is actually implemented.This report is intended to communicate overall quantitative and qualitative EDAPTS system characteristics to users, developers, integrators, dispatchers, administrative staff and others. It is considered as the foundation for prioritizing customer needs and wants. It will be used to establish the baseline for the system requirements definition in the design process.