Railway/Highway At-Grade Crossing Surface Rehabilitation Manual: Recommendations and Guides

This Railway/Highway At-Grade Crossing Surface Rehabilitation Manual offers guidance to engineers and project planners for designing, constructing, and managing railway/highway crossing rehabilitation projects. The manual includes information on pre-project administration, project execution, and post-project management and oversight. Suggestions are provided for determining the most cost-effective rehabilitation procedure, techniques to insure the appropriate installation procedures are followed onsite, and instructions for post-project administration and inspection procedures. The primary goal of this manual is to aid with the implementation of a crossing rehabilitation program; all of its guidance underscores the importance of achieving costeffective solutions through the use of best practices to build crossings that are safe and smooth, perform at a high level, and have a long service life, which benefits railroads as well the driving public

Recommendations for KYTC’s Railway/Highway At-Grade Crossing Surface Management Practices

An ideal Railway/Highway At-Grade Crossing Management program involves selecting costeffective practices when designing new crossings and rehabilitating existing crossings. This report outlines two strategies to enhance KYTC’s existing program. First, it describes a process that uses decision-option diagrams to optimize the assessment and implementation of engineering solutions in order to restore desired smoothness, minimize settlement in the postconstruction phase, and foster acceptable long-term performance of crossings following their rehabilitation. Decision-option diagrams rely on assessments that are site-specific and based on historical performance, the present observed performance and condition, and the measureable parameters specific to particular crossings. To supplement this process, the second strategy that this report proposes is the establishment of an effective managerial structure at KYTC that streamlines decision-making to ensure that the selected design is properly applied and implemented. Taken together, these proposals will significantly improve the state’s ability to systematically and cost-effectively repair deteriorated crossings

Novel gene variants predict serum levels of the cytokines IL-18 and IL-1ra in older adults

Activation of inflammatory pathways measured by serum inflammatory markers such as interleukin-18 (IL-18) and interleukin-1 receptor antagonist (IL-1ra) is strongly associated with the progression of chronic disease states in older adults. Given that these serum cytokine levels are in part a heritable trait, genetic variation may predict increased serum levels. Using the Cardiovascular Health Study and InCHIANTI cohorts, a genome-wide association study was performed to identify genetic variants that influence IL18 and IL-1ra serum levels among older adults. Multiple linear regression models characterized the association between each SNP and log-transformed cytokine values. Tests for multiple independent signals within statistically significant loci were performed using haplotype analysis and regression models conditional on lead SNP in each region. Multiple SNPs were associated with these cytokines with genome-wide significance, including SNPs in the IL18-BCO gene region of chromosome 2 for IL-18 (top SNP rs2250417, P = 1.9×10(−32)) and in the IL1 gene family region of chromosome 2 for IL-1ra (rs6743376, P = 2.3×10(−26)). Haplotype tests and conditional linear regression models showed evidence of multiple independent signals in these regions. Serum IL-18 levels were also associated with a region on chromosome 2 containing the NLRC4 gene (rs12989936, P = 2.7×10(−19)). These data characterize multiple robust genetic signals that influence IL-18 and IL-1ra cytokine production. In particular, the signal for serum IL-18 located on chromosome two is novel and potentially important in inflammasome triggered chronic activation of inflammation in older adults. Replication in independent cohorts is an important next step, as well as molecular studies to better understand the role of NLRC4