Prepublication Now Available

While research and empirical evidence have shown positive safety and operational benefits associated with good access management practices, it can be challenging for transportation agencies to implement access management strategies on the basis of safety performance without methods and tools to quantify the safety performance of alternatives.

The TRB National Cooperative Highway Research Program's pre-publication draft of NCHRP Research Report 974: Application of Crash Modification Factors for Access Management, Volume 1: Practitioner’s Guide presents methods to help transportation planners, designers, and traffic engineers quantify the safety impacts of access management strategies and make more informed access-related decisions on urban and suburban arterials.

Supplementary to the report is the pre-publication draft of NCHRP Research Report 974: Application of Crash Modification Factors for Access Management, Volume 2: Research Overview and a summary presentation for the two volumes.

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Topics: Transportation and Infrastructure

Final Book Now Available

The 1st Edition, in 2010, of the AASHTO Highway Safety Manual revolutionized transportation engineering practice by providing crash modification factors and functions, along with methods that use safety performance functions for estimating the number of crashes within a corridor, subsequent to implementing safety countermeasures.

The TRB National Cooperative Highway Research Program's NCHRP Research Report 974: Application of Crash Modification Factors for Access Management, Volume 2: Research Overview documents the research process related to access management features. The research project is also summarized in this presentation.

NCHRP Research Report 974: Application of Crash Modification Factors for Access Management, Volume 1: Practitioner’s Guide presents methods to help transportation practitioners quantify the safety impacts of access management strategies and make more informed access-related decisions on urban and suburban arterials.

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Topics: Transportation and Infrastructure

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This report evaluates submissions received in response to a Request for Proposals (RFP) for Biomolecular Simulation Time on Anton 2, a supercomputer designed and built by D. E. Shaw Research (DESRES). Over the past 11 years, DESRES has made an Anton or Anton 2 system housed at the Pittsburgh Supercomputing Center available to the non-commercial research community, based on the advice of previous committees of the National Academies of Sciences, Engineering, and Medicine. The goal of the twelfth RFP for simulation time on Anton 2 is to continue to facilitate breakthrough research in the study of biomolecular systems by providing a massively parallel system specially designed for molecular dynamics simulations. These capabilities allow multi-microsecond simulation timescales. The program seeks to continue to support research that addresses important and high impact questions demonstrating a clear need for Anton's special capabilities.

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Topics: Math, Chemistry, and Physics

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Part-time shoulder use is a congestion relief strategy that allows use of the left or right shoulders as travel lanes during some, but not all, hours of the day.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 309: Safety Performance of Part-Time Shoulder Use on Freeways, Volume 2: Conduct of Research Report describes the development of crash prediction models for freeways with PTSU operation.

Supplemental to the document is a Freeway Analysis Tool, which includes BOS data, S D PTSU Data, and a Prediction Tool, as well as NCHRP Web-Only Document 309: Safety Performance of Part-Time Shoulder Use on Freeways, Volume 1: Informational Guide and Safety Evaluation Guidelines.

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Topics:

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Left or right shoulders can be strategically opened as travel lanes, and "part-time shoulder use" is defined as using a shoulder "some, but not all, hours of the day.”

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 309: Safety Performance of Part-Time Shoulder Use on Freeways, Volume 1: Informational Guide and Safety Evaluation Guidelines provides an overview of part-time shoulder use, presents the results of past operational studies, and presents the results of safety research conducted through NCHRP's Safety Performance of Part-time Shoulder Use on Freeways project.

Supplemental to the document is a Freeway Analysis Tool, which includes BOS data, S D PTSU Data, and a Prediction Tool, as well as NCHRP Web-Only Document 309: Safety Performance of Part-Time Shoulder Use on Freeways, Volume 2: Conduct of Research Report.

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Topics:

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There are approximately 1,000 movable highway bridges in the U.S. inventory.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 314: Updating the AASHTO LRFD Movable Highway Bridge Design Specifications allows bridge owners the option of employing site-specific conditions to develop the design wind speed and provides other general updates to previous research from 2000 that reflects changes in design practice and other standards.

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Topics:

Prepublication Now Available

We live in a time of extraordinary discovery and progress in astronomy and astrophysics. The next decade will transform our understanding of the universe and humanity's place in it. Every decade the U.S. agencies that provide primary federal funding for astronomy and astrophysics request a survey to assess the status of, and opportunities for the Nation's efforts to forward our understanding of the cosmos. Pathways to Discovery in Astronomy and Astrophysics for the 2020s identifies the most compelling science goals and presents an ambitious program of ground- and space-based activities for future investment in the next decade and beyond. The decadal survey identifies three important science themes for the next decade aimed at investigating Earth-like extrasolar planets, the most energetic processes in the universe, and the evolution of galaxies. The Astro2020 report also recommends critical near-term actions to support the foundations of the profession as well as the technologies and tools needed to carry out the science.

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Topics: Space and Aeronautics

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Each year, the Gulf Research Program (GRP) produces an annual report to summarize how funds were used. These reports review accomplishments, highlight activities, and, over time, will assess metrics to determine how the program is progressing in accomplishing its goals. The 2020 annual report is the seventh report in this series.

The GRP is an independent, science-based program founded in 2013. Through grants, fellowships, and other activities, it seeks to enhance oil system safety and the protection of human health and the environment in the Gulf of Mexico region and other areas along the U.S. outer continental shelf with offshore oil and gas operations.

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Topics: Environment and Environmental Studies

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The U.S. medical countermeasures (MCMs) enterprise is interconnected, complex, and dynamic. It includes public and private entities that develop and manufacture new and existing MCMs, ensure procurement, storage, and distribution of MCMs, and administer, monitor, and evaluate MCMs. The interagency group known as the Public Health Emergency Medical Countermeasures Enterprise (PHEMCE) is the nation's sole coordinating body, responsible for ensuring end-to-end MCM preparedness and response.

Ensuring an Effective Public Health Emergency Medical Countermeasures Enterprise provides recommendations from an expert committee for a re-envisioned PHEMCE. Four priority areas of improvement emerged from committee deliberations: (1) articulating PHEMCE's mission and role and explicating the principles guiding PHEMCE's operating principles and processes, (2) revising PHEMCE operations and processes, (3) collaborating more effectively with external public and private partners, and (4) navigating legal and policy issues.

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Topics: Health and Medicine

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Connected vehicle deployments in rural areas present opportunities for potential improvements in safety, mobility, and efficiency. It is important for the agencies that operate and maintain rural corridors to have a vision for connected vehicle deployment.

The National Cooperative Highway Research Program's NCHRP Research Report 978: Initiating the Systems Engineering Process for Rural Connected Vehicle Corridors, Volume 2: Model Concept of Operations is designed to guide agencies responsible for rural corridors as they begin to assess their needs, operational concepts, scenarios, and requirements for connected vehicle deployment.

Supplemental to this report are a research overview (Volume 1), a model system requirements specification (Volume 3), and a PowerPoint presentation of context diagrams.

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Topics: Transportation and Infrastructure

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Rural corridors often include long stretches of highway with limited power, communications, and intelligent transportation systems (ITS) infrastructure; long distances between cities or services for travelers; different traffic and roadway characteristics; and significant incident-related rerouting distances.

The National Cooperative Highway Research Program's NCHRP Research Report 978: Initiating the Systems Engineering Process for Rural Connected Vehicle Corridors, Volume 3: Model System Requirements Specification provides information that will apply in general to most current and proposed systems. It is intended to provide a base document that a deploying agency can customize to fit their project and situation.

Supplemental to this report are a research overview (Volume 1), a model concept of operations (Volume 2), and a PowerPoint presentation of context diagrams.

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Topics: Transportation and Infrastructure

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Transit vehicle fires have safety implications for passengers and employees as well as liability implications for manufacturers, suppliers, and operators. Many of the electrical/arcing fire events experienced in the transit industry have led to a total loss of the vehicle and/or serious smoke incidents.

The TRB Transit Cooperative Research Program's TCRP Research Report 229: Assessing and Mitigating Electrical Fires on Transit Vehicles provides transit systems with information and techniques to avoid the interruption of revenue service, passenger injuries, and expenditures of operating and capital funds that occur as the result of fires on transit buses and rail vehicles.

Supplemental to the report is a Presentation describing details of the project.

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Topics: Transportation and Infrastructure

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The Antarctic's unique environment and position on the globe make it a prime location to gain insights into how Earth and the universe operate. This report assesses National Science Foundation (NSF) progress in addressing three priority research areas identified in a 2015 National Academies report: (1) understanding the linkages between ice sheets and sea-level rise, including both a focus on current rates of ice sheet change and studies of past major ice sheet retreat episodes; (2) understanding biological adaptations to the extreme and changing Antarctic environment; and (3) establishing a next-generation cosmic microwave background (CMB) program, partly located in Antarctica, to study the origins of the universe.

NSF has made important progress understanding the impacts of current ice sheet change, particularly through studies focused on the ice sheet and ocean interactions driving ongoing ice mass loss at the Thwaites Glacier and Amundsen Sea region in West Antarctica. Less progress has been made on studies of past major ice sheet retreat episodes. Progress is also strong on CMB research to understand the origins of the universe. Progress has lagged on understanding biological adaptations, in part because of limited community organization and collaboration toward the priority. To accelerate progress during the second half of the initiative, NSF could issue specific calls for proposals, develop strategies to foster collaborations and partnerships, and commission a transparent review of logistical capacity to help illuminate strategies and priorities for addressing resource constraints. Such efforts would also help optimize science and proposal development in an environment of inherently constrained logistics.

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Topics: Earth Sciences

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Topology optimization is a digital method for designing objects in order to achieve the best structural performance, sometimes in combination with other physical requirements. Topology optimization tools use mathematical algorithms, such as the finite element method and gradient computation, to generate designs based on desired characteristics and predetermined constraints. Initially a purely academic tool, topology optimization has advanced rapidly and is increasingly being applied to the design of a wide range of products and components, from furniture to spacecraft.

To explore the potential and challenges of topology optimization, the National Academies of Sciences, Engineering, and Medicine hosted a two-day workshop on November 19-20, 2019, Exploiting Advanced Manufacturing Capabilities: Topology Optimization in Design. The workshop was organized around three main topics: how topology optimization can incorporate manufacturability along with functional design; challenges and opportunities in combining multiple physical processes; and approaches and opportunities for design of soft and compliant structures and other emerging applications. Speakers identified the unique strengths of topology optimization and explored a wide range of techniques and strengths of topology optimization and explored a wide range of techniques and achievements in the field to date. This publication summarizes the presentations and discussion of the workshop.

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Topics: Industry and Labor | Engineering and Technology

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Project-level Programmatic Agreements (PAs) streamline and expedite the environmental review process and provide departments of transportation with greater flexibility in decision making regarding adverse effects to historic properties and defining appropriate mitigation.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 311: Improving the Efficiency and Consistency of Section 106 Compliance for State DOTs: Strategies for Project-Level Programmatic Agreements provides state DOTs, FHWA, SHPOs, and Tribal Historic Preservation Officers with an analysis of the common challenges and successful practices related to the development and execution of project-level PAs.

A dataset is provided as supplemental to the report.

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Topics: Transportation and Infrastructure

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Antimicrobial resistance is a health problem that threatens to undermine almost a century of medical progress. Moreover, it is a global problem that requires action both in the United States and internationally.

Combating Antimicrobial Resistance and Protecting the Miracle of Modern Medicine discusses ways to improve detection of resistant infections in the United States and abroad, including monitoring environmental reservoirs of resistance. This report sets out a strategy for improving stewardship and preventing infections in humans and animals. The report also discusses the strength of the pipeline for new antimicrobial medicines and steps that could be taken to bring a range of preventive and therapeutic products for humans and animals to the market.

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Topics: Health and Medicine

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In 1999, the Federal Communications Commission (FCC) allocated the intelligent transportation system (ITS) band, also known as the “5.9 GHz band,” for transportation purposes including connected and automated vehicle (CAV) technologies. These technologies enable a host of applications for vehicle‐to-vehicle, vehicle‐to‐infrastructure, and vehicle‐to‐pedestrian communication — collectively known as vehicle‐to‐everything (V2X). Today, the connectivity required for V2X is enabled by dedicated short‐range communications and cellular V2X.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 310: Evaluation and Synthesis of Connected Vehicle Communication Technologies presents a compilation of material on the 5.9 GHz band and the actions taken by the FCC from 2019 through early 2021 to reallocate portions of this band away from dedicated use for traffic flow, traffic safety, and other ITS applications that are essential for CAVs.

Supplementary to the document is a video.

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Topics: Transportation and Infrastructure

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Prior to this research project, state highway agencies did not have tools for reflecting safety in their decisions concerning freeway and interchange projects.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 306: Safety Prediction Methodology and Analysis Tool for Freeways and Interchanges documents a safety prediction method for freeways that is suitable for incorporation in the Highway Safety Manual. Within the document are Appendices A through F: Practitioner Interviews, Database Enhancement, Proposed HSM Freeways Chapter, Proposed HSM Ramps Chapter, Proposed HSM Appendix B for Part C, and Algorithm Description.

Supplemental to the document are an Enhanced Safety Analysis Tool, a User Manual for the Tool, a Workshop Agenda, an Instructor Guide, and a PowerPoint Presentation.

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Topics: Transportation and Infrastructure

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Starting in early childhood, children are capable of learning sophisticated science and engineering concepts and engage in disciplinary practices. They are deeply curious about the world around them and eager to investigate the many questions they have about their environment. Educators can develop learning environments that support the development and demonstration of proficiencies in science and engineering, including making connections across the contexts of learning, which can help children see their ideas, interests, and practices as meaningful not just for school, but also in their lives. Unfortunately, in many preschool and elementary schools science gets relatively little attention compared to English language arts and mathematics. In addition, many early childhood and elementary teachers do not have extensive grounding in science and engineering content.

Science and Engineering in Preschool through Elementary Grades provides evidence-based guidance on effective approaches to preschool through elementary science and engineering instruction that supports the success of all students. This report evaluates the state of the evidence on learning experiences prior to school; promising instructional approaches and what is needed for implementation to include teacher professional development, curriculum, and instructional materials; and the policies and practices at all levels that constrain or facilitate efforts to enhance preschool through elementary science and engineering.

Building a solid foundation in science and engineering in the elementary grades sets the stage for later success, both by sustaining and enhancing students' natural enthusiasm for science and engineering and by establishing the knowledge and skills they need to approach the more challenging topics introduced in later grades. Through evidence-based guidance on effective approaches to preschool through elementary science and engineering instruction, this report will help teachers to support the success of all students.

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Topics: Education

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Biometrics is one of the most powerful, but misunderstood technologies used at airports today. The ability to increase the speed of individual processes, as well as offer a touch-free experience throughout an entire journey is a revolution that is decades in the making.

The TRB Airport Cooperative Research Program's ACRP Research Report 233: Airport Biometrics: A Primer is designed to help aviation stakeholders, especially airport operators, to understand the range of issues and choices available when considering, and deciding on, a scalable and effective set of solutions using biometrics. These solutions may serve as a platform to accommodate growth as well as addressing the near-term focus regarding safe operations during the COVID-19 pandemic.

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Topics: Transportation and Infrastructure

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Investment and innovation in drug research and development (R&D) for highly prevalent chronic diseases has stalled in recent decades, despite half of all Americans living with at least one chronic disease. As a result, prevalent chronic diseases are producing immense health care costs as well as preventable suffering and death. On February 22, March 2, and March 8, 2021, the National Academies of Sciences, Engineering, and Medicine, convened a workshop to discuss barriers to innovation in this space and examine strategies and incentives to support equitable, person-centered drug R&D for prevalent chronic diseases.

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Topics: Health and Medicine

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As the largest generation in U.S. history - the population born in the two decades immediately following World War II - enters the age of risk for cognitive impairment, growing numbers of people will experience dementia (including Alzheimer's disease and related dementias). By one estimate, nearly 14 million people in the United States will be living with dementia by 2060. Like other hardships, the experience of living with dementia can bring unexpected moments of intimacy, growth, and compassion, but these diseases also affect people's capacity to work and carry out other activities and alter their relationships with loved ones, friends, and coworkers. Those who live with and care for individuals experiencing these diseases face challenges that include physical and emotional stress, difficult changes and losses in their relationships with life partners, loss of income, and interrupted connections to other activities and friends. From a societal perspective, these diseases place substantial demands on communities and on the institutions and government entities that support people living with dementia and their families, including the health care system, the providers of direct care, and others.

Nevertheless, research in the social and behavioral sciences points to possibilities for preventing or slowing the development of dementia and for substantially reducing its social and economic impacts. At the request of the National Institute on Aging of the U.S. Department of Health and Human Services, Reducing the Impact of Dementia in America assesses the contributions of research in the social and behavioral sciences and identifies a research agenda for the coming decade. This report offers a blueprint for the next decade of behavioral and social science research to reduce the negative impact of dementia for America's diverse population. Reducing the Impact of Dementia in America calls for research that addresses the causes and solutions for disparities in both developing dementia and receiving adequate treatment and support. It calls for research that sets goals meaningful not just for scientists but for people living with dementia and those who support them as well.

By 2030, an estimated 8.5 million Americans will have Alzheimer's disease and many more will have other forms of dementia. Through identifying priorities social and behavioral science research and recommending ways in which they can be pursued in a coordinated fashion, Reducing the Impact of Dementia in America will help produce research that improves the lives of all those affected by dementia.

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Topics: Behavioral and Social Sciences | Health and Medicine

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Since bridges cross over large spans of space they often cross significant features such as busy transportation corridors. In addition, bridges carry heavy vehicles sometimes with dangerous cargos, such as fuel and hazardous chemicals.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 307: Recommended Guidelines for the Selection of Test Levels 2 Through 5 Bridge Railings proposes selection guidelines to assist bridge engineers and highway designers in selecting an appropriate test level for bridge railings based on specific site and traffic conditions.

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Topics: Transportation and Infrastructure

Prepublication Now Available

Fundamentally changing the culture of a transportation agency and integrating those changes into historically siloed management practices, requires the earnest focus of the entire organization, including participation of practically every individual.

The TRB National Cooperative Highway Research Program's pre-publication draft of NCHRP Research Report 985: Integrating Effective Transportation Performance, Risk, and Asset Management Practices is designed to be a process framework that is resilient to the expected evolution of an agency as it matures in its management integration.

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Topics: Transportation and Infrastructure

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Although the need for a more effective set of short- and long-term transportation resilience strategies is increasingly obvious and urgent, many knowledge gaps and institutional barriers still exist.

The TRB National Cooperative Highway Research Program's NCHRP Research Report 975: Transportation System Resilience: Research Roadmap and White Papers highlights significant knowledge gaps within AASHTO and state departments of transportation, presents a 5-year research plan that addresses these gaps, and discusses critical resilience-related issues facing senior transportation leaders today.

Supplementary materials to the report include a Road Map Ratings and Rankings Workbook (Appendix B) and a Resilience Research Roadmap and White Papers Presentation.

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Topics: Transportation and Infrastructure

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Although only 19% of the population lives in rural areas, more than 70% of the U.S.’s four million miles of roadways are in rural areas. The rural transportation system also includes numerous airports; railways; inland and coastal waterways; rural and intercity buses; and bicycle, pedestrian, and multi-use paths and trails. In addition, approximately 47% of the nation’s motor vehicle fatalities occur in rural areas.

The TRB National Cooperative Highway Research Program's pre-publication draft of NCHRP Research Report 988: Rural Transportation Issues: Research Roadmap is designed to assist state departments of transportation and other public agencies and help inform policy–driven investment decisions.

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Topics: Transportation and Infrastructure

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The National Science Foundation (NSF) has played a key role over the past several decades in advancing understanding of Earth's systems by funding research on atmospheric, ocean, hydrologic, geologic, polar, ecosystem, social, and engineering-related processes. Today, however, those systems are being driven like never before by human technologies and activities. Our understanding has struggled to keep pace with the rapidity and magnitude of human-driven changes, their impacts on human and ecosystem sustainability and resilience, and the effectiveness of different pathways to address those challenges.

Given the urgency of understanding human-driven changes, NSF will need to sustain and expand its efforts to achieve greater impact. The time is ripe to create a next-generation Earth systems science initiative that emphasizes research on complex interconnections and feedbacks between natural and social processes. This will require NSF to place an increased emphasis on research inspired by real-world problems while maintaining their strong legacy of curiosity driven research across many disciplines – as well as enhance the participation of social, engineering, and data scientists, and strengthen efforts to include diverse perspectives in research.

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Topics: Earth Sciences

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There appear to be, in this preliminary assessment, no formidable issues that present design and engineering challenges for installing in-cabin wheelchair securement systems in airplanes. While equipping enough airplanes with securement systems to provide meaningful levels of airline service would require substantial effort, the types of cabin modifications required to provide the needed space and structural support would likely be of moderate technical complexity for many individual airplanes.

TRB’s Special Report 341: Technical Feasibility of a Wheelchair Securement Concept for Airline Travel: A Preliminary Assessment identifies and examines potential technical challenges to the development and implementation of an in-cabin wheelchair securement system.

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Topics: Transportation and Infrastructure

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Porous Friction Course (PFC) mixtures are designed with an open aggregate structure to yield high inplace air voids (i.e., typically between 15 and 20 percent). This allows rainwater to drain horizontally through the layer toward the edge of the pavement structure, thereby improving pavement surface friction.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 305: Validation of a Performance-Based Mix Design Method for Porous Friction Courses is designed to assist state highway agencies in implementing the proposed performance-based mix design procedure, verify if the thresholds proposed in the procedure could be achieved, and refine the procedure if needed.

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Topics: Transportation and Infrastructure

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The demand for public transportation investments far exceeds the funds available. While states and communities seek additional revenue sources to maintain current transit assets and serve rapidly changing travel markets, they need methods to help decide where to allocate their limited resources.

The TRB Transit Cooperative Research Program's TCRP Research Report 227: Prioritization of Public Transportation Investments: A Guide for Decision-Makers provides practical advice for transportation agencies looking to improve their prioritization practice for public transportation projects.

There is also a presentation available for use on the project's summary and results.

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Topics: Transportation and Infrastructure

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Guardrails are an important feature of the roadside that are used to shield errant motorists from becoming involved in even more catastrophic crashes by redirecting vehicles away from fixed hazards such as trees and poles and terrain hazards such as steep roadside slopes and fill embankments.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 304: Criteria for Restoration of Longitudinal Barriers, Phase II develops a Field Guide to assist maintenance personnel in making decisions about repairing damaged guardrail installations.

Supplementary material to the document is Appendices A-S.

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Topics: Transportation and Infrastructure

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In the United States, transit oriented development (TOD) is now recognized as a critical element in the planning, development, and execution of transit projects. Recent legislation has been designed to streamline the approval processes for new transportation projects, focus more on safety, and establish new programs to advance critical freight projects.

The TRB Transit Cooperative Research Program's TCRP Legal Research Digest 56: Joint Development Agreements Using FTA Funds or FTA-Funded Assets aims to clarify the Federal Transit Administration (FTA) assisted joint development process and attempts to separate public perceptions (and misperceptions) about TOD from reality. It is an update to TCRP Legal Research Digest 12:The Zoning and Real Estate Implications of Transit-Oriented Development.

Appendix C incudes sample model agreement forms, developed from Washington Area Transit Authority’s Office of Real Estate and Station Planning Templates.

Topics: Transportation and Infrastructure

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Rethinking mission and service delivery, rethinking fare policy, giving transit priority, careful partnering with shared-use mobility providers, and encouraging transit-oriented density are among the strategies transit agencies can employ to increase ridership and mitigate or stem declines in ridership that started years before the COVID-19 pandemic.

The TRB Transit Cooperative Research Program's pre-publication draft of TCRP Research Report 231: Recent Decline in Public Transportation Ridership: Analysis, Causes, and Responses provides a deep-dive exploration of the ridership losses already being experienced by transit systems prior to the COVID-19 pandemic and explores strategies that appear to be key as we move to the new normal of a post-pandemic world.

[Read the full report]

Topics: Transportation and Infrastructure

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The decade ahead will test the nation's nearly 4 million nurses in new and complex ways. Nurses live and work at the intersection of health, education, and communities. Nurses work in a wide array of settings and practice at a range of professional levels. They are often the first and most frequent line of contact with people of all backgrounds and experiences seeking care and they represent the largest of the health care professions.

A nation cannot fully thrive until everyone - no matter who they are, where they live, or how much money they make - can live their healthiest possible life, and helping people live their healthiest life is and has always been the essential role of nurses. Nurses have a critical role to play in achieving the goal of health equity, but they need robust education, supportive work environments, and autonomy. Accordingly, at the request of the Robert Wood Johnson Foundation, on behalf of the National Academy of Medicine, an ad hoc committee under the auspices of the National Academies of Sciences, Engineering, and Medicine conducted a study aimed at envisioning and charting a path forward for the nursing profession to help reduce inequities in people's ability to achieve their full health potential. The ultimate goal is the achievement of health equity in the United States built on strengthened nursing capacity and expertise. By leveraging these attributes, nursing will help to create and contribute comprehensively to equitable public health and health care systems that are designed to work for everyone.

The Future of Nursing 2020-2030: Charting a Path to Achieve Health Equity explores how nurses can work to reduce health disparities and promote equity, while keeping costs at bay, utilizing technology, and maintaining patient and family-focused care into 2030. This work builds on the foundation set out by The Future of Nursing: Leading Change, Advancing Health (2011) report.

[Read the full report]

Topics: Health and Medicine

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CEOs of departments of transportation (DOTs) face many challenges, including some that will have serious impacts on people's mobility and safety, and possibly on the tenure of CEOs. Many of these challenges revolve around the resilience of the transportation system—how well it can withstand disruptions from natural causes, catastrophic failures of the infrastructure or cyber events, and how quickly the agency can restore services when they are impacted.

The TRB National Cooperative Highway Research Program's NCHRP Research Report 976: Resilience Primer for Transportation Executives provides a quick grounding in resilience benefits, the CEO’s role in resilience, and approaches taken in various states to increase the resilience of their transportation system. It also offers concepts and tools to lead agencies toward greater resilience.

An electronic brochure, Resilience in Your Pocket, details for practitioners internal and external resilience talking points and action steps.

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Topics: Transportation and Infrastructure

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A central goal of U.S. fisheries management is to control the exploitation of fish populations so that fisheries remain biologically productive, economically valuable, and socially equitable. Although the Magnuson-Stevens Fishery Conservation and Management Act led to many improvements, a number of fish populations remained overfished and some fisheries were considered economically inefficient. In response, Congress amended the Act in 2006 to allow additional management approaches, including Limited Access Privilege Programs (LAPPs) in which individuals receive a permit to harvest a defined portion of the total allowable catch for a particular fish stock.

This report examines the impacts of LAPPs on mixed-use fisheries, defined as fisheries where recreational, charter, and commercial fishing sectors target the same species or stocks. The report offers recommendations for NOAA's National Marine Fisheries Service (NMFS) and the Regional Fishery Management Councils (the Councils) who oversee and manage federally regulated fisheries. For each of the five mixed-use fisheries included in the report, the committee examined available fisheries data and analyses and collected testimony from fishery participants, relevant Councils, and NMFS regional experts through a series of public meetings.

[Read the full report]

Topics: Agriculture | Earth Sciences

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Significant progress has been made over the last decade in integrating resilience criteria into transportation decision-making. A compelling case remains for investing in making transportation projects more resilient in the face of increasing and intensifying storms, floods, droughts, and other natural hazards that are combining with sea-level rise, new temperature and precipitation norms, and other effects from climate change.

TRB’s Special Report 340: Investing in Transportation Resilience: A Framework for Informed Choices reviews current practices by transportation agencies for evaluating resilience and conducting investment analysis for the purpose of restoring and adding resilience. These practices require methods for measuring the resilience of the existing transportation system and for evaluating and prioritizing options to improve resilience by strengthening, adding redundancy to, and relocating vulnerable assets.

Supplemental to the report is a Report Highlights three-pager.

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Topics: Transportation and Infrastructure

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Transportation Systems Management and Operations (TSMO) programs include elements of operations, planning, design, construction, maintenance, and safety. They are frequently complex and cross jurisdictional boundaries, involving traditional state departments of transportation (DOTs), local DOTs, and metropolitan planning organizations (MPOs), along with disruptive technology markets.

The TRB National Cooperative Highway Research Program's NCHRP Synthesis 567: Summary State DOT Practices for Developing and Implementing TSMO Plans documents current practices used by state DOTs related to the development and implementation of TSMO plans from state DOTs and MPOs. The study develops an overview of the current state of TSMO plan development and methodology.

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Topics: Transportation and Infrastructure

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Light emitting diode (LED) technology has revolutionized the lighting industry. The dimming and instant-on capabilities of these light sources along with their high efficiency have allowed lighting designers to overcome some of the limitations of previous technologies, particularly in roadway lighting environments. However, concerns related to the health and environmental impacts of LEDs have been raised.

The TRB National Cooperative Highway Research Program's NCHRP Research Report 968: LED Roadway Lighting: Impact on Driver Sleep Health and Alertness seeks to determine the impact of LED roadway lighting on driver sleep health and alertness.

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Topics: Transportation and Infrastructure

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Si vous utilisez encore les anciens RDA ou ANR, il est temps de passer aux ANREF. Dietary Reference Intakes: The Essential Guide to Nutrient Requirements, rédigé par l'Institute of Medicine en partenarait avec Santé Canada fournit les renseignements les plus exacts, pratiques et à jour pour élaborer des programmes éducatifs sur la nutrition, évaluer et planifier des régimes alimentaires pour des individus et des groupes, fixer des normes pour les programmes d'aide alimentaire et l'étiquetage nutritionnel, faciliter le développment de nouveaux produits par l'industrie et évaluer l'appovisionnement alimentaire relatifs aux besoins nutritionnels de la population.

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Topics: Food and Nutrition

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One in five people in the United States had a sexually transmitted infection (STI) on any given day in 2018, totaling nearly 68 million estimated infections. STIs are often asymptomatic (especially in women) and are therefore often undiagnosed and unreported. Untreated STIs can have severe health consequences, including chronic pelvic pain, infertility, miscarriage or newborn death, and increased risk of HIV infection, genital and oral cancers, neurological and rheumatological effects. In light of this, the Centers for Disease Control and Prevention, through the National Association of County and City Health Officials, commissioned the National Academies of Sciences, Engineering, and Medicine to convene a committee to examine the prevention and control of sexually transmitted infections in the United States and provide recommendations for action.

In 1997, the Institute of Medicine released a report, The Hidden Epidemic: Confronting Sexually Transmitted Diseases. Although significant scientific advances have been made since that time, many of the problems and barriers described in that report persist today; STIs remain an underfunded and comparatively neglected field of public health practice and research. The committee reviewed the current state of STIs in the United States, and the resulting report, Sexually Transmitted Infections: Advancing a Sexual Health Paradigm, provides advice on future public health programs, policy, and research.

[Read the full report]

Topics: Health and Medicine

Prepublication Now Available

The Roundtable on Population Health Improvement of the National Academies of Sciences, Engineering, and Medicine convened a workshop at Hunter College in New York City, New York on February 6, 2020, to explore the value of co-creating and keeping inclusive healthy spaces. The workshop was designed to understand and highlight the economics of inclusive placemaking and to explore its value in improving health, equity, and well-being. Placemaking (the work of creating livable, vibrant, or quality places, especially public places) draws on various traditions of community development, arts and culture, regional planning, and civic engagement, combining different disciplinary perspectives into a creative way of shaping public spaces, land use, commerce, transportation, housing, and social fabric.

The workshop (1) examined the economics of this work, (2) described how inclusive placemakers gather resources to do their work, and (3) explored the social and economic value they are able to generate when places are designed with health, equity, and well-being in mind. This publication is a summary of the presentations and discussions that occurred during the workshop.

[Read the full report]

Topics: Health and Medicine

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Marine recreational fishing is a popular activity enjoyed by more than 9 million Americans annually and is a driver of the American ocean-or blue-economy. To ensure that fish populations are not overexploited, the NOAA Fisheries' Marine Recreational Information Program (MRIP) monitors recreational catch through a variety of in-person, telephone, mail-in, and other surveys. NOAA Fisheries' management of recreational catch also must take into account annual catch limits (ACLs) established to prevent overfishing for all managed species in federal waters.

While MRIP has worked to improve recreational catch surveys over the past decade, the surveys were never designed to meet the demands of in-season management of ACLs. In some cases, estimates of harvest have triggered accountability measures such as early season closures and reductions in future recreational ACLs, which have been a source of contention with the recreational fishing community. This report presents approaches for optimizing MRIP data and complementary data for in-season management and considers alternatives for managing recreational fisheries with ACLs to better serve both social and economic management objectives.

[Read the full report]

Topics: Earth Sciences

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TRB’s Airport Cooperative Research Program (ACRP) Report 51: Risk Assessment Method to Support Modification of Airfield Separation Standards is intended to be used to support requests for modification of standards in those circumstances where the design criteria for separations between taxiways/taxilanes and other taxiways/taxilanes and fixed or movable objects as well as separations between taxiways and runways cannot be met.

The following appendices, included in the pdf and print version of the report, will be helpful in understanding the methodology.

• Appendix A: Risk Assessment Methodology presents a methodology for five different types of circumstances: taxiway/taxilane to taxiway, taxiway to object, taxilane to taxilane, taxilane to an object, and runway to taxiway/taxilane or object;
• Appendix F: Aircraft Database Summary presents a summary of aircraft characteristics by model; and
• Appendix H: Analysis of MOS Cases summarizes information collected in the modification of standards survey and presents results of application of the methodology described in Appendix A to each modification of standards case.

Other report appendices, which are available online only, provide detail and information on the development of the methodology.

• Appendix B: Collision Risk Model
• Appendix C: Key Studies on Aircraft Deviation
• Appendix D: List of Veer-Off Accidents and Incidents
• Appendix E: Sample of Normal Operations Data
• Appendix G: Summary of FAA/Boeing Taxiway Deviation Studies

In addition, the project developed a

that may be useful for introducing and explaining the methodology to stakeholders.

In July 2021, an errata was posted for this publication: In Table 7 on page 25, the LDVO coefficient was changed from -3.088 to -13.088. The online version of the report has been corrected.

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Topics: Transportation and Infrastructure

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A workshop, "Revised Contraction Scour Analysis," is presented in this training manual.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 294: Revised Clear-Water and Live-Bed Contraction Scour Analysis Training Manual adheres to the guidance promulgated by the National Highway Institute and the International Association of Continuing Education and Training for adult learning.

The document is supplemental to NCHRP Research Report 971:Revised Clear-Water and Live-Bed Contraction Scour Analysis.

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Topics: Transportation and Infrastructure

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Bridge waterways commonly narrow or constrict natural channels, forcing water to flow through a contracted area, thereby increasing the magnitudes of velocity and turbulent kinetic energy of flow passing through the waterway. If these increases cause erosion of the waterway boundaries, the contracted section may scour.

The TRB National Cooperative Highway Research Program's NCHRP Research Report 971: Revised Clear-Water and Live-Bed Contraction Scour Analysis develops live-bed and clear-water contraction scour equations suitable for use in risk-based bridge design encompassing a wide range of hydraulic conditions, including varying contraction ratios.

Supplemental to the report is NCHRP Web-Only Document 294: Revised Clear-Water and Live-Bed Contraction Scour Analysis Training Manual and a Presentation.

[Read the full report]

Topics: Transportation and Infrastructure

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Scientific thinking and understanding are essential for all people navigating the world, not just for scientists and other science, technology, engineering and mathematics (STEM) professionals. Knowledge of science and the practice of scientific thinking are essential components of a fully functioning democracy. Science is also crucial for the future STEM workforce and the pursuit of living wage jobs. Yet, science education is not the national priority it needs to be, and states and local communities are not yet delivering high quality, rigorous learning experiences in equal measure to all students from elementary school through higher education.

Call to Action for Science Education: Building Opportunity for the Future articulates a vision for high quality science education, describes the gaps in opportunity that currently exist for many students, and outlines key priorities that need to be addressed in order to advance better, more equitable science education across grades K-16. This report makes recommendations for state and federal policy makers on ways to support equitable, productive pathways for all students to thrive and have opportunities to pursue careers that build on scientific skills and concepts. Call to Action for Science Education challenges the policy-making community at state and federal levels to acknowledge the importance of science, make science education a core national priority, and empower and give local communities the resources they must have to deliver a better, more equitable science education.

[Read the full report]

Topics: Education

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Each year, tens of millions of individuals in the U.S. suffer from neurological and psychiatric disorders including neurodegenerative diseases such as Alzheimer's Disease and Parkinson's Disease, and psychiatric disorders such as autism spectrum disorder, depression and schizophrenia. Treatments for these diseases are often completely lacking or only partially effective, due in large part to the difficulty of conducting brain research and the complexity of the brain itself.

Researchers in recent years have developed new models to better represent and study the human brain. The three models considered in this report, all of which generate and use pluripotent stem cells from healthy individuals and patients, are human neural organoids, human neural transplants, and human-animal neural chimeras. The Emerging Field of Human Neural Organoids, Transplants, and Chimeras: Science, Ethics, and Governance reviews the status of research, considers its benefits and risks, discusses associated ethical issues, and considers governance mechanisms for this type of research.

[Read the full report]

Topics: Health and Medicine

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The year 2020 presented extraordinary challenges to organizations working to improve population health - from public health agencies at all levels of government to health systems to community-based non-profit organizations responding to health-related social needs. To improve understanding of how different domains in the population health field are responding to and being changed by two major crises (racial injustice and the COVID-19 pandemic), the Roundtable on Population Health Improvement of the National Academies of Sciences, Engineering, and Medicine held a workshop from September 21-24, 2020, titled Population Health in Challenging Times: Insights from Key Domains. The workshop had sessions organized by themes: academic public health and population health; the social sector; health care, governmental public health; philanthropy; and cross-sector work. Each panel discussion highlighted difficulties and opportunities, both internal to the respective institutions and sectors, and at the interface with peers and partners, especially communities. This publication summarizes the presentations and panel discussions from the workshop.

[Read the full report]

Topics: Health and Medicine

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Bridge approach systems are used by state departments of transportation (DOTs) to form a smooth transition between the roadway and bridges. Adequate performance of bridge approaches is of extreme importance to transportation agencies as they affect both safety and the public perception of ride quality if the transition is not smooth.

The TRB National Cooperative Highway Research Program's NCHRP Synthesis 566: Practices for Bridge Approach Systems documents the current state of the practice at state DOTs related to the design, construction, and maintenance of bridge approach systems. State DOT design guides and standard specifications were reviewed as part of the information-gathering process.

[Read the full report]

Topics: Transportation and Infrastructure

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Portland cement concrete (PCC) pavement joint sealing material technology has evolved in recent decades, and the effect of current joint sealant practice has not been well documented. Therefore, it is necessary to establish a standardized approach to joint sealant evaluation as well as to investigate the practice of joint sealant in PCC pavement design.

The TRB National Cooperative Highway Research Program's NCHRP Synthesis 568: Portland Cement Concrete Pavement Joint Sealant Practices and Performance compiles and documents information regarding the current state of practice of joint sealing PCC by state departments of transportation.

[Read the full report]

Topics: Transportation and Infrastructure

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Prior to 1976, federal highway funds could only be used for the construction of new highways or the reconstruction of existing highways. The Federal-Aid Highway Act of 1976 allowed the use of federal aid for resurfacing, restoration, and rehabilitation (3R) projects on federal-aid highways. However, in 1976 there were no standards for 3R improvements.

The TRB National Cooperative Highway Research Program's NCHRP Research Report 876: Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects presents a rational approach for estimating the cost-effectiveness of including safety and operational improvements in a resurfacing, restoration, or rehabilitation (3R) project.

The approach uses the performance of the existing road in estimating the benefits and cost-effectiveness of proposed design improvements. These guidelines are intended to replace TRB Special Report 214: Designing Safer Roads: Practices for Resurfacing, Restoration, and Rehabilitation.

Supplemental materials include NCHRP Web-Only Document 244: Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Two spreadsheet tools for benefit–cost analysis in support of design decisions for 3R projects also accompany the report. Spreadsheet Tool 1 is a tool for analysis of a single design alternative or combination of alternatives. Spreadsheet Tool 2 is a tool for comparison of several design alternatives or combinations of alternatives.

[Read the full report]

Topics: Transportation and Infrastructure

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The aging U.S. highway system, coupled with fiscal constraints, is placing increased pressures on highway agencies to maintain the highway system in a cost-effective manner and is, thus, creating greater needs for 3R projects.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 244: Developing Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects presents the results of research to develop improved design guidelines for 3R projects. The guidelines were developed to replace the older guidance presented in TRB Special Report 214: Designing Safer Roads: Practices for Resurfacing, Restoration, and Rehabilitation.

Supplementary to the Document is NCHRP Research Report 876: Guidelines for Integrating Safety and Cost-Effectiveness into Resurfacing, Restoration, and Rehabilitation (3R) Projects. Two spreadsheet tools for benefit–cost analysis in support of design decisions for 3R projects also accompany the report. Spreadsheet Tool 1 is a tool for analysis of a single design alternative or combination of alternatives. Spreadsheet Tool 2 is a tool for comparison of several design alternatives or combinations of alternatives.

[Read the full report]

Topics: Transportation and Infrastructure

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The past century has witnessed remarkable advances in life expectancy in the United States and throughout the world. In 2010, however, progress in life expectancy in the United States began to stall, despite continuing to increase in other high-income countries. Alarmingly, U.S. life expectancy fell between 2014 and 2015 and continued to decline through 2017, the longest sustained decline in life expectancy in a century (since the influenza pandemic of 1918-1919). The recent decline in U.S. life expectancy appears to have been the product of two trends: (1) an increase in mortality among middle-aged and younger adults, defined as those aged 25-64 years (i.e., "working age"), which began in the 1990s for several specific causes of death (e.g., drug- and alcohol-related causes and suicide); and (2) a slowing of declines in working-age mortality due to other causes of death (mainly cardiovascular diseases) after 2010.

High and Rising Mortality Rates among Working Age Adults highlights the crisis of rising premature mortality that threatens the future of the nation's families, communities, and national wellbeing. This report identifies the key drivers of increasing death rates and disparities in working-age mortality over the period 1990 to 2017; elucidates modifiable risk factors that could alleviate poor health in the working-age population, as well as widening health inequalities; identifies key knowledge gaps and make recommendations for future research and data collection to fill those gaps; and explores potential policy implications. After a comprehensive analysis of the trends in working-age mortality by age, sex, race/ethnicity, and geography using the most up-to-date data, this report then looks upstream to the macrostructural factors (e.g., public policies, macroeconomic trends, social and economic inequality, technology) and social determinants (e.g., socioeconomic status, environment, social networks) that may affect the health of working-age Americans in multiple ways and through multiple pathways.

[Read the full report]

Topics: Behavioral and Social Sciences

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High-quality primary care is the foundation of the health care system. It provides continuous, person-centered, relationship-based care that considers the needs and preferences of individuals, families, and communities. Without access to high-quality primary care, minor health problems can spiral into chronic disease, chronic disease management becomes difficult and uncoordinated, visits to emergency departments increase, preventive care lags, and health care spending soars to unsustainable levels.

Unequal access to primary care remains a concern, and the COVID-19 pandemic amplified pervasive economic, mental health, and social health disparities that ubiquitous, high-quality primary care might have reduced. Primary care is the only health care component where an increased supply is associated with better population health and more equitable outcomes. For this reason, primary care is a common good, which makes the strength and quality of the country's primary care services a public concern.

Implementing High-Quality Primary Care: Rebuilding the Foundation of Health Care puts forth an evidence-based plan with actionable objectives and recommendations for implementing high-quality primary care in the United States. The implementation plan of this report balances national needs for scalable solutions while allowing for adaptations to meet local needs.

[Read the full report]

Topics: Health and Medicine

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The income that supports the activities of the National Academy of Sciences(NAS) comes from two major sources: program revenue received from government and other sponsors to pay for the large number of studies and other activities undertaken each year by the National Research Council (NRC), and a much smaller sum that we withdraw from our own endowment under the endowment spending policies adopted by the Council.

This last year presented many challenges for the institution, as the COVID-19 pandemic began to effect operations in March 2020. At that time, the NAS/NRC decided to move to remote work for all staff and virtual meetings for committee and other convening activities. The move to virtual activity has been more successful than envisioned, with each part of the institution being able to operate surprisingly efficiently and effectively in such an environment. During the period from March through December 2020, the institution held hundreds of virtual webinars, workshops, lectures, and symposia, some with attendance into the thousands. The NRC released approximately 200 consensus studies, proceedings, and other publications during this period.

This Report of the Treasurer of the National Academy of Sciences presents the financial position and results of operations as well as a review of the endowment and other long-term investments portfolio activities of our Academy for the year ended December 31, 2020.

[Read the full report]

Topics: Policy for Science and Technology

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Over the past 15 years, the nation’s transportation systems have experienced numerous significant disruptions that have resulted in economic loss and loss of human life. The 2020 COVID-19 pandemic is a recent example of how unexpected events can affect the performance and role of transportation systems.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 293: Deploying Transportation Resilience Practices in State DOTs examines the concept of transportation system resilience and how state departments of transportation could mainstream resilience-related approaches and procedures into their culture. The document is related to NCHRP Research Report 970: Mainstreaming System Resilience Concepts into Transportation Agencies: A Guide.

Supplemental materials to the report include RISE Posters and the Program and Highlights from the Transportation Resilience Innovations Summit and Exchange in October 2018.

[Read the full report]

Topics: Transportation and Infrastructure

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Transportation officials recognize that a reliable and sustainable transportation system is needed to fulfill their agency’s mission and goals.

The TRB National Cooperative Highway Research Program's NCHRP Research Report 970: Mainstreaming System Resilience Concepts into Transportation Agencies: A Guide provides transportation officials with a self-assessment tool to assess the current status of an agency’s efforts to improve the resilience of the transportation system through the mainstreaming of resilience concepts into agency decision-making and procedures. The tool can be applied to a broad array of natural and human-caused threats to transportation systems and services. The report is related to NCHRP Web-Only Document 293: Deploying Transportation Resilience Practices in State DOTS.

Supplemental materials to the report include a Posters Compilation and the Program Agenda from the 2018 Transportation Resilience Innovations Summit and Exchange, and a PowerPoint Presentation on resilience.

[Read the full report]

Topics: Transportation and Infrastructure

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Liquefied natural gas (LNG) has not been transported to any significant degree by freight railroads in the United States. When the Further Consolidated Appropriations Act of 2020 was enacted, it directed the Pipeline and Hazardous Materials Safety Administration (PHMSA) to enter into an agreement with the National Academies of Sciences, Engineering, and Medicine (NASEM) to convene a committee of independent experts to study the safe transportation of LNG by rail tank car.

TRB Special Report 339: Preparing for LNG by Rail Tank Car: A Review of a U.S. DOT Safety Research, Testing, and Analysis Initiative, from TRB and NASEM, finds that PHMSA’s task force presented a comprehensive plan of work that built on longstanding safety programs, as well as surfacing opportunities for future research. The findings in the report will serve as a good base for the second phase of TRB’s phased continued study of the issue. The next phase will be informed by this technical report; will consider experience transporting LNG in other modes, including marine tankers and cargo tank trucks; and will examine the applicability of existing emergency response plans, protocols, and guides for responding to any possible hazardous materials incidents of transporting LNG by rail.

[Read the full report]

Topics: Transportation and Infrastructure

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Several controlled laboratory studies have shown that air voids (AV) can have a large effect on the performance of asphalt pavements. AVs that are either too high or too low can cause a reduction in pavement life.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 299: Investigating the Relationship of As-Constructed Asphalt Pavement Air Voids to Pavement Performance determines the effect of in-place AVs on the performance of asphalt concrete (AC) pavements.

The document also has supplemental appendices that are available by request to Ed Harrigan. They include data sets for LTPP, Pavement ME Design Validation, MnROAD Validation, and NCAT Validation.

[Read the full report]

Topics: Transportation and Infrastructure

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Several types of speed limits exist, including statutory speed limit, posted speed limit, school zone speed limit, work zone speed limit, variable speed limit, and advisory speed.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 291: Development of a Posted Speed Limit Setting Procedure and Tool documents the research efforts and findings from an NCHRP Project 17-76 to identify factors that influence a driver’s operating speed and the development of a Speed Limit Setting Procedure and Tool.

The document is supplemental to NCHRP Research Report 966: Posted Speed Limit Setting Procedure and Tool: User Guide.

[Read the full report]

Topics: Transportation and Infrastructure

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Electric power is essential for the lives and livelihoods of all Americans, and the need for electricity that is safe, clean, affordable, and reliable will only grow in the decades to come. At the request of Congress and the Department of Energy, the National Academies convened a committee of experts to undertake a comprehensive evaluation of the U.S. grid and how it might evolve in response to advances in new energy technologies, changes in demand, and future innovation.

The Future of Electric Power in the United States presents an extensive set of policy and funding recommendations aimed at modernizing the U.S. electric system. The report addresses technology development, operations, grid architectures, and business practices, as well as ways to make the electricity system safe, secure, sustainable, equitable, and resilient.

[Read the full report]

Topics: Energy and Energy Conservation

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As technology evolves, airports and their partners collect more data from passengers, employees, tenants, concessionaires, airlines, and others. This data is used in many ways, including for facility management, security, ground transportation, marketing, understanding passenger preferences, and enhancing the travel experience.

The TRB Airport Cooperative Research Program's ACRP Legal Research Digest 42: Legal Implications of Data Collection at Airports provides a survey of applicable law; considerations for the collection and safekeeping of data; and a review of the issues that arise related to data collection among airports, their tenants, and other users. It also offers an understanding of the expansion in law around data collection and use.

[Read the full report]

Topics: Transportation and Infrastructure

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Joint development is a subset of transit‐oriented development. It consists of residential, commercial, civic, or mixed‐use development that is closely coordinated with a transit facility and in which the transit agency participates through the use of its property, funding, or some other form of real estate or business transaction.

The TRB Transit Cooperative Research Program's TCRP Web-Only Document 73: Guide to Joint Development for Public Transportation Agencies: Appendices provides supplemental information to TCRP Research Report 224: Guide to Joint Development for Public Transportation Agencies.

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Topics: Transportation and Infrastructure

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Joint development is real estate development that occurs on transit agency property or through some other type of development transaction to which the transit agency is a party.

The TRB Transit Cooperative Research Program's TCRP Research Report 224: Guide to Joint Development for Public Transportation Agencies is designed to expand the successful use of joint development in North American transit systems—in the volume and variety of projects undertaken, the diversity of transit agencies participating, and the quality of outcomes achieved.

Supplemental to the report is TCRP Web-Only Document 73:Guide to Joint Development for Public Transportation Agencies: Appendices, the Executive Summary, and a long version presentation and a short version presentation of "Guide to Joint Development for Public Transportation Agencies."

[Read the full report]

Topics: Transportation and Infrastructure

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Transportation is a major source of the greenhouse gas (GHG) emissions that are causing climate change. As communities work to cut emissions and become more resilient, they are including public transportation advances as a significant part of their climate action strategies.

The TRB Transit Cooperative Research Board's TCRP Research Report 226: An Update on Public Transportation's Impacts on Greenhouse Gas Emissions provides updated national analysis of public transportation’s role as a climate solution by documenting its 2018 GHG impacts.

Supplemental materials to the report include three factsheets (Fact Sheet 1, Fact Sheet 2, and Fact Sheet 3); various key findings regarding transit as a climate solution; a PowerPoint presentation summarizing the findings and research and a template for transit agencies to add their own data for climate communications; and a simple spreadsheet tool that provides this study’s 2018 GHG impact findings by transit agency and allows the user to apply several of the future scenarios to see how their transit agency’s GHG impacts change with electrification, clean power, and ridership increases.

[Read the full report]

Topics: Transportation and Infrastructure

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The spring of 2020 marked a change in how almost everyone conducted their personal and professional lives, both within science, technology, engineering, mathematics, and medicine (STEMM) and beyond. The COVID-19 pandemic disrupted global scientific conferences and individual laboratories and required people to find space in their homes from which to work. It blurred the boundaries between work and non-work, infusing ambiguity into everyday activities. While adaptations that allowed people to connect became more common, the evidence available at the end of 2020 suggests that the disruptions caused by the COVID-19 pandemic endangered the engagement, experience, and retention of women in academic STEMM, and may roll back some of the achievement gains made by women in the academy to date.

The Impact of COVID-19 on the Careers of Women in Academic Sciences, Engineering, and Medicine identifies, names, and documents how the COVID-19 pandemic disrupted the careers of women in academic STEMM during the initial 9-month period since March 2020 and considers how these disruptions - both positive and negative - might shape future progress for women. This publication builds on the 2020 report Promising Practices for Addressing the Underrepresentation of Women in Science, Engineering, and Medicine to develop a comprehensive understanding of the nuanced ways these disruptions have manifested. The Impact of COVID-19 on the Careers of Women in Academic Sciences, Engineering, and Medicine will inform the academic community as it emerges from the pandemic to mitigate any long-term negative consequences for the continued advancement of women in the academic STEMM workforce and build on the adaptations and opportunities that have emerged.

[Read the full report]

Topics: Policy for Science and Technology

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In the United States, many transit stops are not adequate: bus stops that are just a signpost on a busy road, bus stops with broken sidewalks and/or pathway obstructions, bus stops with a lack of seating, and bus stops clearly not accessible to people with disabilities. For many bus riders, the journey to access and the wait at the bus stop are experiences that may inhibit their ability or desire to take the bus.

The TRB Transit Cooperative Research Program's TCRP Synthesis 152 Transit Agency Relationships and Initiatives to Improve Bus Stops and Pedestrian Access summarizes the current state of practice for bus stop and pedestrian infrastructure improvement programs and processes in place at transit agencies and other public organizations.

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Topics: Transportation and Infrastructure

Prepublication Now Available

The Roundtable on Population Health Improvement of the National Academies of Sciences, Engineering, and Medicine hosted a public workshop on September 19, 2019 titled Models for Population Health Improvement by Health Care Systems and Partners: Tensions and Promise on the Path Upstream. The term upstream refers to the higher levels of action to improve health. Medical services act downstream (i.e., at the patient level) in improving population health, while such activities as screening and referring to social and human services (e.g., for housing, food assistance) are situated midstream, and the work of changing laws, policies, and regulations (e.g., toward affordable housing, expanding healthy food access) to improve the community conditions for health represents upstream action.

The workshop explored the growing attention on population health, from health care delivery and health insurance organizations to the social determinants of health and their individual-level manifestation as health-related social needs, such as patients' needs. The workshop showcased collaborative population health improvement efforts, each of which included one or more health systems. This publication summarizes the presentations and discussions from the workshop.

[Read the full report]

Topics: Health and Medicine

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The airport environment is facing a shortage of individuals who can lead, guide, manage, and carry out airport-centric initiatives to support the aviation industry.

The TRB Airport Cooperative Research Program's ACRP Research Report 232: Playbook for Cultivating Talent in the Airport Environment provides inspiring, proven, and readily implementable techniques for airport leaders and managers to use to enhance talent cultivation and knowledge transfer within airport organizations.

Supplemental to the report is a presentation.

[Read the full report]

Topics: Transportation and Infrastructure

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State departments of transportation (DOTs) conduct planning and administer funding programs for the implementation of pedestrian and bicycle projects. The amount of federal funds available for these projects has grown steadily since 1992 under programs implemented as part of the Intermodal Surface Transportation Efficiency Act.

The TRB National Cooperative Highway Research Program's NCHRP Synthesis 564: Practices for Selecting Pedestrian and Bicycle Projects documents and summarizes state DOT practices for selecting pedestrian and bicycle projects, excluding design elements.

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Topics: Transportation and Infrastructure

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Asphalt binders experience aging that occurs in two distinct stages under quite different conditions: (1) short-term during construction (plant mixing, storage, placement, and compaction) and (2) long-term during the service life of the pavement.

The TRB National Cooperative Highway Research Program's NCHRP Research Report 967: Asphalt Binder Aging Methods to Accurately Reflect Mixture Aging documents research conducted to improve laboratory binder conditioning methods to accurately simulate the short-term and long-term aging of asphalt binders, and to calibrate the improved procedures to the aging that occur during mixture production, transport, and placement as well as during the service life of the pavement structure.

[Read the full report]

Topics: Transportation and Infrastructure

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Millions of people are living with dementia in the United States and globally. To live well with dementia, people need care, services, and supports that reflect their values and preferences, build on their strengths and abilities, promote well-being, and address needs that evolve as cognitive impairment deepens.

Persons living with dementia co-manage their care with or rely on the support of a wide range of care partners and caregivers, including spouses, other family members and friends, and direct care workers in homes or residential care settings. While dementia care has improved since the 1970s, many individuals still lack access to high-quality care and are not living as well as they might. Disadvantaged groups, especially racial and ethnic minorities, still face challenges in access to care, services, and supports, due to deep and persistent inequities.

Meeting the Challenge of Caring for Persons Living with Dementia and Their Care Partners and Caregivers: A Way Forward examines the complex body of evidence on dementia care and informs decision making about which interventions are ready to be broadly disseminated and implemented. It also offers a blueprint to guide future research using rigorous, cutting-edge methods that are inclusive, equitable, and yield critical information for real-world implementation, toward the ultimate goal of better supporting persons living with dementia and their care partners and caregivers in living as well as possible.

[Read the full report]

Topics: Health and Medicine

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The release of the Highway Safety Manual (HSM) by the American Association of State Highway and Transportation Officials (AASHTO) in 2010 was a landmark event in the practice of road safety analysis. Before it, the United States had no central repository for information about quantitative road safety analysis methodology.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 295: Improved Prediction Models for Crash Types and Crash Severities describes efforts to develop improved crash prediction methods for crash type and severity for the three facility types covered in the HSM—specifically, two‐lane rural highways, multilane rural highways, and urban/suburban arterials.

Supplemental materials to the Web-Only Document include Appendices A, B, and C (Average Condition Models, Crash Severities – Ordered Probit Fractional Split Modeling Approach, and Draft Content for Highway Safety Manual, 2nd Edition).

[Read the full report]

Topics: Transportation and Infrastructure

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The first edition of the Highway Safety Manual (HSM), in 2010, included Safety Performance Functions (SPFs) for roadway segments and intersections. However, not all intersection types are covered in the first edition of the HSM.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 297: Intersection Crash Prediction Methods for the Highway Safety Manual develops SPFs for new intersection configurations and traffic control types not covered in the first edition of the HSM, for consideration in the second edition of the HSM.

Supplemental to the Document is recommended draft text for the second edition if the HSM, a worksheet for Chapter 10, a worksheet for Chapter 11, a worksheet for Chapter 12, a worksheet for Chapter 19, and a presentation.

[Read the full report]

Topics: Transportation and Infrastructure

Prepublication Now Available

The accurate characterization of the in situ aging of asphalt pavement materials over the service life of the pavement is of utmost importance to the implementation of mechanistic empirical (ME) pavement design and analysis methods.

The TRB National Cooperative Highway Research Program's pre-publication draft of NCHRP Research Report 973: Long-Term Aging of Asphalt Mixtures for Performance Testing and Prediction: Phase III Results refines the aging procedure developed in the original NCHRP Research Report 871: Long-Term Aging of Asphalt Mixtures for Performance Testing and Prediction. The updates field calibrate the original project aging model (PAM), develop procedures to estimate the PAM inputs, and develop a framework by which the predicted changes in asphalt binder properties that are due to oxidative aging can be related to corresponding changes in asphalt mixture performance.

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Topics: Transportation and Infrastructure

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Airports and their support industries have changed significantly over the past several decades. It is imperative that academic programs continue to evolve with these changes to better prepare the next generation of airport industry professionals.

The TRB Airport Cooperative Research Program's ACRP Research Report 230: Enhancing Academic Programs to Prepare Future Airport Industry Professionals provides guidance to assist academia in preparing graduates for careers as airport industry professionals.

A supplemental presentation is available.

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Topics: Transportation and Infrastructure

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Federal Aviation Administration (FAA) regulations require the licensing of spaceports and launch vehicles, which includes the assessment of environmental impacts.

The TRB Airport Cooperative Research Program’s ACRP Web-Only Document 51: Commercial Space Vehicle Emissions Modeling presents a user-friendly tool for practitioners to estimate the emissions associated with commercial space vehicle activity.

Supplementary materials to the document include an Emissions Example Information & Users Guide, the RUMBLE application, and a RUMBLE User Guide.

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Topics: Transportation and Infrastructure

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Today, transit agencies gather and manage more data than ever. However, data processing, exploration, the development of performance metrics, and communicating decisions are often fragmented and scattered across many departments.

The TRB Transit Cooperative Research Program's TCRP Synthesis 153: The Transit Analyst Toolbox: Analysis and Approaches for Reporting, Communicating, and Examining Transit Data will assist transit agencies that want to develop and/or adopt a data-driven culture.

The survey results are provided in detail in Appendix B, which is a separate file.

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Topics: Transportation and Infrastructure

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Run-off-road traffic crashes account for almost one-third of the deaths and serious injuries each year on U.S. highways.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 296: Guidelines for Cost-Effective Safety Treatments of Roadside Ditches provides new proposed design guidance for the configuration of ditches adjacent to the roadway.

A supplemental PowerPoint Summary is available.

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Topics: Transportation and Infrastructure

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Computing in some form touches nearly every aspect of day to day life and is reflected in the ubiquitous use of cell phones, the expansion of automation into many industries, and the vast amounts of data that are routinely gathered about people's health, education, and buying habits. Computing is now a part of nearly every occupation, not only those in the technology industry. Given the ubiquity of computing in both personal and professional life, there are increasing calls for all learners to participate in learning experiences related to computing including more formal experiences offered in schools, opportunities in youth development programs and after-school clubs, or self-initiated hands-on experiences at home. At the same time, the lack of diversity in the computing workforce and in programs that engage learners in computing is well-documented.

It is important to consider how to increase access and design experiences for a wide range of learners. Authentic experiences in STEM - that is, experiences that reflect professional practice and also connect learners to real-world problems that they care about - are one possible approach for reaching a broader range of learners. These experiences can be designed for learners of all ages and implemented in a wide range of settings. However, the role they play in developing youths' interests, capacities, and productive learning identities for computing is unclear. There is a need to better understand the role of authentic STEM experiences in supporting the development of interests, competencies, and skills related to computing.

Cultivating Interest and Competencies in Computing examines the evidence on learning and teaching using authentic, open-ended pedagogical approaches and learning experiences for children and youth in grades K-12 in both formal and informal settings. This report gives particular attention to approaches and experiences that promote the success of children and youth from groups that are typically underrepresented in computing fields. Cultivating Interest and Competencies in Computing provides guidance for educators and facilitators, program designers, and other key stakeholders on how to support learners as they engage in authentic learning experiences.

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Topics: Education | Computers and Information Technology

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From daily commutes to cross-country road trips, millions of light-duty vehicles are on the road every day. The transportation sector is one of the United States’ largest sources of greenhouse gas emissions, and fuel is an important cost for drivers. The period from 2025-2035 could bring the most fundamental transformation in the 100-plus year history of the automobile. Battery electric vehicle costs are likely to fall and reach parity with internal combustion engine vehicles. New generations of fuel cell vehicles will be produced. Connected and automated vehicle technologies will become more common, including likely deployment of some fully automated vehicles. These new categories of vehicles will for the first time assume a major portion of new vehicle sales, while internal combustion engine vehicles with improved powertrain, design, and aerodynamics will continue to be an important part of new vehicle sales and fuel economy improvement.

This study is a technical evaluation of the potential for internal combustion engine, hybrid, battery electric, fuel cell, nonpowertrain, and connected and automated vehicle technologies to contribute to efficiency in 2025-2035. In addition to making findings and recommendations related to technology cost and capabilities, Assessment of Technologies for Improving Light-Duty Vehicle Fuel Economy - 2025-2035 considers the impacts of changes in consumer behavior and regulatory regimes.

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Topics: Environment and Environmental Studies | Transportation and Infrastructure

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Effective transportation asset management (TAM) depends on having good data about the assets under management, their descriptions, current condition and history, functional performance, and the activities conducted to develop, maintain, improve, and rehabilitate them during the course of their service lives.

The TRB National Cooperative Highway Research Program's NCHRP Research Report 956: Guidebook for Data and Information Systems for Transportation Asset Management presents a structured approach for assessing an organization’s current data and information management practices in support of transportation asset management and strategies for improving these practices.

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Topics: Transportation and Infrastructure

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Estimates indicate that more than 14 million jobs—about 11% of civilian jobs in the United States—are related to infrastructure. Transportation has the potential to be a major U.S. job creator with projections to add 417,000 net jobs from 2012 to 2022. An additional 4.2 million workers will need to be hired to fill vacancies created by people leaving the transportation workforce.

Transportation workforce strategies are highly decentralized with no national standards for operations, planning, or programming. This is not necessarily a criticism because there is tremendous variation in the transportation workforce needs from state to state. However, it means there is little documentation of best practices, making it difficult to know what innovation can be transferred from state to state.

The TRB National Cooperative Highway Research Program's NCHRP Synthesis 543: Transportation Workforce Planning and Development Strategies is a synthesis of the current state of practice associated with the implementation of transportation workforce planning and development strategies at state departments of transportation (DOTs) and associated local and tribal technical assistance programs (LTAPs/TTAPs).

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Topics: Transportation and Infrastructure

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Ongoing and emerging shifts in customer ground access behavior, resulting from the growing use of transportation network companies (TNCs) and the eventual adoption of emerging technologies, are posing a significant challenge to the reliance of airports on parking revenue.

The TRB Airport Cooperative Research Program's ACRP Research Report 225: Rethinking Airport Parking Facilities to Protect and Enhance Non-Aeronautical Revenues is a guidance document that identifies near-term and long-term solutions to help airports of all types and sizes repurpose, renovate, or redevelop their parking facilities to address the loss of revenue from airport parking and other ground transportation services.

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Topics: Transportation and Infrastructure

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The Bureau of Safety and Environmental Enforcement (BSEE), in seeking to augment and improve its offshore oil and gas inspection program, should focus less on inspecting all oil platforms and become more outcome-based by focusing on the riskiest entities.

These are among the findings in TRB Special Report 338: Modernizing the U.S. Offshore Oil and Gas Inspection Program for Increased Agility and Safety Vigilance, from the Transportation Research Board of the National Academies of Sciences, Engineering, and Medicine.

Given the expectation that it inspect each offshore facility at least once per year, BSEE faces many challenges as it seeks to fulfill its stated mission “to promote safety, protect the environment, and conserve resources through vigorous regulatory oversight.” Although BSEE has taken a number of initiatives to meet these challenges, it faces many constraints and will need to make many strategic-level choices to innovate and evolve its inspection program to keep pace with the continually changing offshore energy landscape.

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Topics: Transportation and Infrastructure

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Over the last decade, state departments of transportation (DOTs) have begun to use vehicle probe and cellular GPS data for a variety of purposes, including real-time traffic and incident monitoring, highway condition, and travel demand management. DOTs are also using vehicle probe and cellular GPS data to inform system planning and investment decisions.

The TRB National Cooperative Highway Research Program'sNCHRP Synthesis 561: Use of Vehicle Probe and Cellular GPS Data by State Departments of Transportation documents how DOTs are applying vehicle probe and cellular GPS data for planning and real-time traffic and incident monitoring and communication.

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Topics: Transportation and Infrastructure

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The need for sustainable agriculture is becoming ever more significant. The world's population is still increasing, requiring more from our agricultural systems. Malnutrition and diet-related illnesses are present in nearly all societies. At the same time, agriculture plays a significant role in some of the biggest environmental challenges that humanity is facing, including the climate crisis, biodiversity loss, deforestation, and the pollution of our soil, water, and air. The need to balance the growing demand for nutritious food with these environmental threats is a complex issue, and ensuring sustainable food systems will require a collaborative effort from many different communities.

These issues were addressed during the US-UK Scientific Forum on Sustainable Agriculture held in Washington, DC, on March 5-6, 2020. Organized by the National Academy of Sciences and the United Kingdom's Royal Society, the forum brought together leading scientists, researchers, policy makers, and practitioners in agricultural sciences, food policy, biodiversity, and environmental science (among other specialties). The forum provided an opportunity for members of these research communities to build multidisciplinary and international collaborations that can inform solutions to a broad set of problems. This publication summarizes the presentations of the forum.

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Topics: Environment and Environmental Studies | Agriculture

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Digital terrain models (DTMs) are three-dimensional (3D) models of the ground surface showing natural features such as ridges and breaklines.

The TRB National Cooperative Highway Research Program's NCHRP Synthesis 560: Practices for Construction-Ready Digital Terrain Models documents processes and strategies used by state departments of transportation (DOTs) for the use and transfer of DTMs from design into the construction phase of highway projects.

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Topics: Transportation and Infrastructure

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Active Traffic Management (ATM) strategies have become more common in the United States as state departments of transportation grapple with increasing congestion and fewer dollars available to add capacity to keep pace.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 286: Principles and Guidance for Presenting Active Traffic Management Information to Drivers develops and details principles and guidance for presenting drivers with dynamic information that can be frequently updated based on real-time conditions.

These principles and guidance should improve the effectiveness of ATM strategies, which include systems to manage congestion, incidents, weather, special events, and work zones.

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Topics: Transportation and Infrastructure

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Airport collaborative decision making (ACDM) is a process in which the stakeholders of operations—airport operators, the air traffic control tower staff, flight operators, ground handlers, fixed-base operators, and others—share information to improve policies, planning, real-time coordination, and decisions regarding operations.

The TRB Airport Cooperative Research Program's ACRP Research Report 229: Airport Collaborative Decision Making (ACDM) to Manage Adverse Conditions proposes a step-by-step approach to achieve ACDM implementation, supported by templates and a workbook, to involve stakeholders, define common goals and objectives, appoint leadership for the initiative, tailor a vision that serves the local needs, and develop a roadmap of successful projects delivering practical improvements.

Of the airports surveyed as part of this project, 67 percent do not hold regular meetings with the flight operators. Interviews with staff at individual airports show a lack of real-time coordination between the stakeholders. However, nearly all the survey participants responded affirmatively that they would consider holding such meetings to improve collaboration because it is commonly understood that more cooperation can help address local issues and improve overall efficiency.

Supplemental materials to the report include a presentation with an overview of ACDM, a toolbox that provides guidance and resources for implementing ACDM, and a text file that contains the steps for opening the toolbox and other materials.

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Topics: Transportation and Infrastructure

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Distracted driving is a complex and ever-increasing risk to public safety on roadways. Drivers’ use of electronic devices significantly diverts human attention resources away from the driving task. The enforcement community faces significant challenges as electronic device use has expanded beyond simply texting or talking. Legislation regulating electronic device use while driving is inconsistent in content and implementation.

The TRB Behavioral Traffic Safety Cooperative Research Program's BTSCRP Research Report 1: Using Electronic Devices While Driving: Legislation and Enforcement Implications presents the results of an examination of the current state and provincial legislation on electronic device use while driving; evaluates the benefits and impediments associated with enacting, enforcing, and adjudicating electronic device use; and proposes model legislation and educational materials that can be used by relevant stakeholders to enact a law and educate key individuals on the importance of the law.

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Topics: Transportation and Infrastructure

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Airport attorneys spend considerable time drafting and negotiating airport contracts that involve specialized legal and business issues. Some are general commercial issues, while others are unique to airports. As governmental entities, airports are subject to a variety of governmental law principles that can affect their contracts for commercial services.

The TRB Airport Cooperative Research Program's ACRP Legal Research Digest 41: Legal Issues Relating to Airport Commercial Contracts complements other ACRP publications that deal with other legal aspects of airport operations and provides a general overview of the types of agreements airports use and includes other government law principles that also can affect government contracts for commercial services.

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Topics: Transportation and Infrastructure

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An airport emergency plan (AEP) is meant to support airports in defining roles and responsibilities of stakeholders during emergencies, identifying specific threats that could affect airports, and establishing communication protocols for the airport community.

The TRB Airport Cooperative Research Program's ACRP Synthesis 115: Practices in Airport Emergency Plans gathers relevant data specific to AEP practices that can effectively be applied to other airports, including general aviation airports, whether required to maintain an AEP or not.

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Topics: Transportation and Infrastructure

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There is a need to identify new or improved laboratory and field test methods to measure the electrochemical properties of earthen materials surrounding buried or embedded steel elements.

The TRB National Cooperative Highway Research Program's NCHRP Research Report 958: Electrochemical Test Methods to Evaluate the Corrosion Potential of Earthen Materials presents a protocol for evaluating the corrosion potential of earthen materials in contact with steel highway structures.

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Topics: Transportation and Infrastructure

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Highway agencies can use a method to assess roadside hardware and establish priorities on how upgrades of hardware should occur for individual projects or establish policy guidelines on roadside hardware assessments.

The TRB National Cooperative Highway Research Program's NCHRP Web-Only Document 292: Roadside Hardware Replacement Analysis: User Guide presents how to implement and plan for assessing roadside hardware.

Supplemental to the document are an Assessment Worksheet and Project Summary Slides.

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Topics: Transportation and Infrastructure

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The zero‐emission bus (ZEB) market, including Battery Electric Buses and Fuel Cell Electric Buses, has seen significant growth in recent years. ZEBs do not rely on fossil fuels for operation and have zero harmful tailpipe emissions, improving local air quality. The increase in market interest has also helped decrease product pricing.

The TRB Transit Cooperative Research Program's TCRP Research Report 219: Guidebook for Deploying Zero-Emission Transit Buses is designed to provide transit agencies with information on current best practices for ZEB deployments and lessons learned from previous deployments, industry experts, and available industry resources.

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Topics: Transportation and Infrastructure

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Cross-frames are important structural components that serve many functions throughout the service life of steel I-girder bridges. Under repetitive load cycles caused by heavy truck passages, cross-frames and their connections can be susceptible to load-induced fatigue cracking if not properly designed.

The TRB National Cooperative Highway Research Program'sNCHRP Research Report 962: Proposed Modification to AASHTO Cross-Frame Analysis and Design addresses knowledge gaps in an attempt to improve the reliability and economy of cross-frames in steel I-girder bridges and produces quantitatively based methodologies and design guidelines.

Appendices B through F provide examples of cross-frame design for a straight bridge and a curved bridge as well as a comprehensive overview of the work completed in Phases I, II, and III of the project. Appendix A, Proposed Modifications to AASHTO LRFD, will be published by AASHTO.

Appendix B

Appendix C

Appendix D

Appendix E

Appendix F

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Topics: Transportation and Infrastructure

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Student wellbeing is foundational to academic success. One recent survey of postsecondary educators found that nearly 80 percent believed emotional wellbeing is a "very" or "extremely" important factor in student success. Studies have found the dropout rates for students with a diagnosed mental health problem range from 43 percent to as high as 86 percent. While dealing with stress is a normal part of life, for some students, stress can adversely affect their physical, emotional, and psychological health, particularly given that adolescence and early adulthood are when most mental illnesses are first manifested. In addition to students who may develop mental health challenges during their time in postsecondary education, many students arrive on campus with a mental health problem or having experienced significant trauma in their lives, which can also negatively affect physical, emotional, and psychological wellbeing.

The nation's institutions of higher education are seeing increasing levels of mental illness, substance use and other forms of emotional distress among their students. Some of the problematic trends have been ongoing for decades. Some have been exacerbated by the COVID-19 pandemic and resulting economic consequences. Some are the result of long-festering systemic racism in almost every sphere of American life that are becoming more widely acknowledged throughout society and must, at last, be addressed.

Mental Health, Substance Use, and Wellbeing in Higher Education lays out a variety of possible strategies and approaches to meet increasing demand for mental health and substance use services, based on the available evidence on the nature of the issues and what works in various situations. The recommendations of this report will support the delivery of mental health and wellness services by the nation's institutions of higher education.

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Topics: Health and Medicine | Education

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Alternative Intersections and Interchanges (A.I.I.s) are designs that improve operations and safety for motorized traffic by strategically adjusting the geometric features at a given location, working on the general principle of redistributing motor vehicle demand at an intersection in an attempt to limit the need to add capacity with new lanes to improve traffic flow.

The TRB National Cooperative Highway Research Program's NCHRP Research Report 948: Guide for Pedestrian and Bicyclist Safety at Alternative and Other Intersections and Interchanges provides specific guidance for four common A.I.I.s: Diverging Diamond Interchange (DDI), Restricted Crossing U-Turn (RCUT), Median U-Turn (MUT), and Displaced Left-Turn (DLT).

These designs may involve reversing traffic lanes from their traditional directions, which may introduce confusion and create safety issues for pedestrians and bicyclists. In addition, pedestrian paths and bicycle facilities may cross through islands or take different routes than expected. These new designs are likely to require additional information for drivers, bicyclists, and pedestrians as well as better accommodations for pedestrians and bicyclists, including pedestrians with disabilities.

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Topics: Transportation and Infrastructure