Highway Safety Research, Development, and Technology Transfer

Late in 1987, the Federal Highway Administration assembled a seven-member panel which, guided by a primary contractor, Harrison Boyd & Associates, was charged with the task of developing a recommended five-year research, development, and technology transfer program for highway safety starting in the 1990s. As a part of the task, each panel member prepared an individual position paper to stimulate and focus panel discussions and, ultimately, to provide the basis for a consensus paper. This represents one such individual paper. Although it is believed that significant safety gains can be achieved in the 1990s and beyond simply by more extensive implementation of known and proven crash countermeasures, this position paper focuses on research activity, the generation or extension of information related to the enhancement of road safety. Quantum improvement in road safety as a result of highly focused new research appears unlikely. Accordingly, in the quest to achieve significant additional gains, the recommended approach tackles the road safety problem on a broad front, examining a wide variety of factors contributing to travel hazard and building incrementally on existing knowledge. Furthermore, emphasis has been placed on activities likely to yield results that, if implemented, could be expected to generate short-term gains, perhaps within a period as short as five or fewer years. Certainly no claim can ever be made that a specific research program will generate knowledge adequate to sustain high levels of travel safety over long periods of time. The recommended five-year research program is simply an immediate, short-term phase of a continuing process that seeks to retain or enhance a high level of personal safety in face of endless changes in human activity patterns and the highway systems built to accommodate them

Estimation of Equivalent Axleloads: Computer Program Documentation

The estimation of equivalent axleloads (EAL) requires the correlation of several data bases. Described herein are three computer programs which summarize truckweight data and classification data, and combine the two data bases to estimate EAL\u27s for each site where classification counts are available in a given year. The programs also present the data in two matrices to characterize the effects that geographic area, federal-aid classification, coal-haul volume and total volume have on each of the traffic parameters necessary to compute EAL\u27s

Improved single-swab sample preparation for recovering bacterial and phage DNA from human skin and wound microbiomes.

BackgroundCharacterization of the skin and wound microbiome is of high biomedical interest, but is hampered by the low biomass of typical samples. While sample preparation from other microbiomes (e.g., gut) has been the subject of extensive optimization, procedures for skin and wound microbiomes have received relatively little attention. Here we describe an improved method for obtaining both phage and microbial DNA from a single skin or wound swab, characterize the yield of DNA in model samples, and demonstrate the utility of this approach with samples collected from a wound clinic.ResultsWe find a substantial improvement when processing wound samples in particular; while only one-quarter of wound samples processed by a traditional method yielded sufficient DNA for downstream analysis, all samples processed using the improved method yielded sufficient DNA. Moreover, for both skin and wound samples, community analysis and viral reads obtained through deep sequencing of clinical swab samples showed significant improvement with the use of the improved method.ConclusionUse of this method may increase the efficiency and data quality of microbiome studies from low-biomass samples

Microbial predictors of healing and short-term effect of debridement on the microbiome of chronic wounds.

Chronic wounds represent a large and growing disease burden. Infection and biofilm formation are two of the leading impediments of wound healing, suggesting an important role for the microbiome of these wounds. Debridement is a common and effective treatment for chronic wounds. We analyzed the bacterial content of the wound surface from 20 outpatients with chronic wounds before and immediately after debridement, as well as healthy skin. Given the large variation observed among different wounds, we introduce a Bayesian statistical method that models patient-to-patient variability and identify several genera that were significantly enriched in wounds vs. healthy skin. We found no difference between the microbiome of the original wound surface and that exposed by a single episode of sharp debridement, suggesting that this debridement did not directly alter the wound microbiome. However, we found that aerobes and especially facultative anaerobes were significantly associated with wounds that did not heal within 6 months. The facultative anaerobic genus Enterobacter was significantly associated with lack of healing. The results suggest that an abundance of facultative anaerobes is a negative prognostic factor in the chronic wound microbiome, possibly due to the increased robustness of such communities to different metabolic environments

Equivalent Axleloads for Pavement Design

Proper structural design of highway pavements requires an evaluation of the destructive effects of the anticipated vehicular loading. The concept of load equivalency provides a means for expressing these destructive effects in terms of a single measure, the equivalent axleloads (EAL\u27s). The design EAL\u27s represents the equivalent number of applications of a standard or base axleload anticipated during the design life

Flow Behavior of Asphalt Cements

The Kentucky Department of Highways in cooperation with the Bureau of Public Roads is conducting a continuing investigation of the fundamental mechanical properties of flexible pavement materials. The ultimate objective of this investigation is to gain sufficient knowledge of the fundamental mechanical behavior of these materials to support the establishment of a responsive flexible pavement design procedure. A preliminary report, issued in 1964, contained the results of the preparatory phase of this investigation. This report summarized from a theoretical point of view efforts that had been made to quantify the mechanical response of viscoelastic materials to known conditions of loading. In addition, it described the development of a rotating coaxial cylinder viscometer which was designed to measure the creep response in shear of solid or semi-solid bituminous materials. The usefulness of this viscometer was verified by testing a rubberized asphalt cement at several temperature and torque levels. It was found that rubber, when added to the asphalt cement in significant quantities, tended to increase, at the higher temperatures, the steady-state viscosity, the stiffness, the retardation time of the viscoelastic response, and the complexity of flow. The current report summarizes results of a second phase of the continuing investigation in which the preparatory efforts have been expanded to encompass the creep testing of 13 asphalt cements in a second rotating coaxial cylinder viscometer. The 13 asphalt cements were selected to represent a variety of crude sources, penetration grades, and manufacturing processes. Design and construction of the viscometer, which were accomplished as a portion of this phase, reflect the basic features of the earlier viscometer modified on the basis of the recommendations contained in the first report. In analyzing the data reported herein, efforts were made to apply existing theories for simple ideal materials such as the Newtonian liquid and the Bingham plastic whenever these theories produced results in reasonable accord with the actual data. In many instances, however, it was necessary to combine these simple theories with somewhat more complex concepts of linear visco-elasticity in order to adequately characterize the deformation properties of the materials

Determination of Traffic Parameters for the Prediction, Projection, and Computation of EWL’s

One of the first published methods for the structural design of highway pavements was called the Massachusetts Rule and was presented in the eighth annual report of the Massachusetts Highway Commission in 1901 (1). The essence of this procedure was a rather intuitive assumption concerning the distribution of vertical pressures beneath a loaded area. For design purposes, this required the selection of a design load which, since failure was assumed to be catastrophic and not cumulative, could be taken as the largest load that could reasonably be anticipated during the design life of the pavement. The prediction of such a design load was in itself a rather formidable task