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Bridges that are designated historic present a special challenge to bridge engineers whenever rehabilitation work or improvements are made to the bridges. Federal and state laws protect historically significant bridges, and railings on these bridges can be subject to protection because of the role they play in aesthetics. Unfortunately, original railings on historic bridges do not typically meet current crash-test requirements and typically do not meet current standards for railing height and size of permitted openings. The primary objective of this study is to develop strategies that can be used to address existing railings on historic bridges and to develop solutions that meet current design requirements. In addition to the modification, selection, and design of the bridge railing, the bridge deck is also impacted by changes made to the railing. Due to increased force levels recently required by AASHTO, deck overhangs require significantly more reinforcement than for past practice. These increases are being realized on all bridge decks and may pose particular challenges for the attachment of railing to historic bridges. Therefore, a secondary objective of this project is to investigate the design of the deck overhang and determine whether reduced amounts of reinforcement are possible. For Volume 1 (Replacement Strategies), three phases of research were conducted. First, an overview of current practice for addressing historic bridge railings was performed. Second, an investigation was conducted to document historic bridge railings in Indiana. Finally, rehabilitation solutions were developed to address the specific bridge railings found in Indiana. Based on this research, three retrofit strategies were developed which include an inboard railing, curb railing, and a simulated historic railing. These rehabilitation solutions can be used to address historic bridge railings not only in Indiana, but across the country. For Volume 2 (Bridge Deck Overhang Design), experime

Background: We have previously identified a locus on human chromosome 20q13.1, encompassing related genes of postulated WFDC-type protease inhibitors and semen coagulum proteins. Three of the genes with WFDC motif also coded for the Kunitz-type protease inhibitor motif. In this report, we have reinvestigated the locus for homologous genes encoding Kunitz motif only. The identified genes have been analyzed with respect to structure, expression and function. Results: We identified three novel genes; SPINT3, SPINT4 and SPINT5, and the structure of their transcripts were determined by sequencing of DNA generated by rapid amplification of cDNA ends. Each gene encodes a Kunitz domain preceded by a typical signal peptide sequence, which indicates that the proteins of 7.6, 8.7, and 9.7 kDa are secreted. Analysis of transcripts in 26 tissues showed that the genes predominantly are expressed in the epididymis. The recombinantly produced proteins could not inhibit the amidolytic activity of trypsin, chymotrypsin, plasmin, thrombin, coagulation factor Xa, elastase, urokinase and prostate specific antigen, whereas similarly made bovine pancreatic trypsin inhibitor (BPTI) had the same bioactivity as the protein isolated from bovine pancreas. Conclusions: The similar organization, chromosomal location and site of expression, suggests that the novel genes are homologous with the genes of WFDC-type protease inhibitors and semen coagulum proteins, despite the lack of similarity in primary structure of their protein products. Their restricted expression to the epididymis suggests that they could be important for male reproduction. The recombinantly produced proteins are presumably bioactive, as demonstrated with similarly made BPTI, but may have a narrower spectrum of inhibition, as indicated by the lacking activity against eight proteases with differing specificity. Another possibility is that they have lost the protease inhibiting properties, which is typical of Kunitz domains, in f

SPR-3714, Bridges that are designated historic present a special challenge to bridge engineers whenever rehabilitation work or improvements are, made to the bridges. Federal and state laws protect historically significant bridges, and railings on these bridges can be subject to, protection because of the role they play in aesthetics. Unfortunately, original railings on historic bridges do not typically meet current, crash-test requirements and typically do not meet current standards for railing height and size of permitted openings. The primary, objective of this study is to develop strategies that can be used to address existing railings on historic bridges and to develop solutions, that meet current design requirements. In addition to the modification, selection, and design of the bridge railing, the bridge deck is also, impacted by changes made to the railing. Due to increased force levels recently required by AASHTO, deck overhangs require significantly, more reinforcement than for past practice. These increases are being realized on all bridge decks and may pose particular challenges for, the attachment of railing to historic bridges. Therefore, a secondary objective of this project is to investigate the design of the deck, overhang and determine whether reduced amounts of reinforcement are possible. For Volume 1 (Replacement Strategies), three phases, of research were conducted. First, an overview of current practice for addressing historic bridge railings was performed. Second, an, investigation was conducted to document historic bridge railings in Indiana. Finally, rehabilitation solutions were developed to address, the specific bridge railings found in Indiana. Based on this research, three retrofit strategies were developed which include an inboard, railing, curb railing, and a simulated historic railing. These rehabilitation solutions can be used to address historic bridge railings not only, in Indiana, but across the country. For Volume 2 (Bridge Deck Overhang Design), experimental testing of half-scale and full-scale, overhang specimens was conducted, and the results were analyzed. Failures of in-service bridge railings were also evaluated. Based on, this research, recommendations are provided for the more efficient and economic design of bridge deck overhangs. These, recommendations are applicable not only for historic bridges, but for all concrete bridge decks.