Distribution of Wheel Loads on Highway Bridges, 1968

The purpose of the research was to develop a more realistic design criteria for distribution of wheel loads on highway bridges. A comprehensive study was made of the· static load distribution in a broad range of short and medium span bridge types used by today's designers.

Clinton Multimodal (U. S. 30 Mississippi River Bridge) Study, 2003

The purpose of this memorandum is to document the benefit-cost analysis of the river crossing concept alternatives described in the "Concept Alternatives Technical Memo." Benefit-cost studies are designed to measure, in dollars, the potential positive or negative impacts of large-scale construction projects. The concept alternatives analyzed include improvements to the Union Pacific Railroad (UPRR) River Crossing and the U.S. Highway 30 (U.S. 30) River Crossing.

State-of-the-Art Methods for Design of Integral Bridge Abutments, HR-227, 1981

The routine use of integral abutments to tie bridge superstructures to foundation piling began in this country about 30 years ago. Kansas, Missouri, Ohio, North Dakota, and Tennessee were some of the early users. This method of construction has steadily grown more popular. Today more than half of the state highway agencies have developed design criteria for bridges without expansion joint devices.

The Applicability Of Ordered Mesoporous Sba-15 And Its Hydrophobic Glutaraldehyde-bridge Derivative To Improve Ibuprofen-loading In Releasing System.

The mesoporous SBA-15 silica with uniform hexagonal pore, narrow pore size distribution and tuneable pore diameter was organofunctionalized with glutaraldehyde-bridged silylating agent. The precursor and its derivative silicas were ibuprofen-loaded for controlled delivery in simulated biological fluids. The synthesized silicas were characterized by elemental analysis, infrared spectroscopy, (13)C and (29)Si solid state NMR spectroscopy, nitrogen adsorption, X-ray diffractometry, thermogravimetry and scanning electron microscopy. Surface functionalization with amine containing bridged hydrophobic structure resulted in significantly decreased surface area from 802.4 to 63.0 m(2) g(-1) and pore diameter 8.0-6.0 nm, which ultimately increased the drug-loading capacity from 18.0% up to 28.3% and a very slow release rate of ibuprofen over the period of 72.5h. The in vitro drug release demonstrated that SBA-15 presented the fastest release from 25% to 27% and SBA-15GA gave near 10% of drug release in all fluids during 72.5 h. The Korsmeyer-Peppas model better fits the release data with the Fickian diffusion mechanism and zero order kinetics for synthesized mesoporous silicas. Both pore sizes and hydrophobicity influenced the rate of the release process, indicating that the chemically modified silica can be suggested to design formulation of slow and constant release over a defined period, to avoid repeated administration.

Tiering strategic environmental assessment and project environmental impact assessment in highway planning in Sao Paulo, Brazil

Constructing highways in dense urban areas is always a challenge. In Sao Paulo Metropolitan Region, heavy truck traffic contributes to clog streets and expressways alike. As part of the traffic neither originates nor head to the region, a peripheral highway has been proposed to reduce traffic problems. This project called Rodoanel, is an expressway approximately 175 km long. The fact that the projected south and north sections would cross catchments that supply most of the metropolis water demand was strongly disputed and made the environmental permitting process particularly difficult. The agency in charge commissioned a strategic environmental assessment (SEA) of a revamped project, and called it the Rodoanel Programme. However, the SEA report failed to satisfactorily take account of significant strategic issues. Among these, the highway potential effect of inducing urban sprawl over water protection zones is the most critical issue, as it emerged later as a hurdle to project licensing. Conclusion is that, particularly where no agreed-upon framework for SEA exists, when vertical tiering with downstream project EIA is sought, then a careful scoping of strategic issues is more than necessary. If an agreement on `what is strategic` is not reached and not recognized by influential stakeholders, then the unsettled conflicts will be transferred to project EIA. In such a context, SEA will have added another loop to the usually long road to project approval. (c) 2008 Elsevier Inc. All rights reserved.

Modeling technique for honeycomb FRP deck bridges via finite elements

Honeycomb structures have been used in different engineering fields. In civil engineering, honeycomb fiber-reinforced polymer (FRP) structures have been used as bridge decks to rehabilitate highway bridges in the United States. In this work, a simplified finite-element modeling technique for honeycomb FRP bridge decks is presented. The motivation is the combination of the complex geometry of honeycomb FRP decks and computational limits, which may prevent modeling of these decks in detail. The results from static and modal analyses indicate that the proposed modeling technique provides a viable tool for modeling the complex geometry of honeycomb FRP bridge decks. The modeling of other bridge components (e.g., steel girders, steel guardrails, deck-to-girder connections, and pier supports) is also presented in this work.

Historic Bridge Photographs: The Lahey Collection

Romeo Watkins Lahey (1887-1968) was a distinguished Queensland engineer. He graduated in engineering from the University of Sydney in 1914 and served in World War I from 1915 to 1918 with The Royal Australian Engineers. Following the war, he accepted an offer to remain for a period in England and studied town planning at the University of London. He visited Europe and collected a remarkable set of historic bridge photographs. In the course of this visit, he met Paul Sejourne, a distinguished French bridge engineer, the designer of at Ieast one of the bridges (at Fontpedrouse, pages 25-27) included in this set. When Lahey died, his wife Sybil and daughter Ann took steps to give this remarkable set of 58 historic bridge photographs to The University of Queensland. More recently, Lahey's daughters Ann Neale and Alison Drake have given a set of lantern plates collected by their father, many of which also have photographs of bridges. This volume is divided into three parts: (a) a biography of Romeo Watkins Lahey, written by his daughter, Ann Neale; (b) copies of the original set of 58 bridge photographs, and (c) copies taken from 32 lantern plates. To these have been added captions. Many of the original photographs carried titles; where these are available they have been printed in italics. Further work has been done to identify bridges and where possible the captions include the completion date, major dimensions, locations, and references to published works. Plates 8.1-10 are copies of drawings used as Figures in a book. These drawings have not been copied and the source has not been identified. Two lists of photographs and plates are included - the first in the order of the original collections and a second with bridges listed in the order of material, structural form and date. The collection is of remarkable value to any bridge historian, and is recommended for study by students.

Role of the 6-20 disulfide bridge in the structure and activity of epidermal growth factor

Two synthetic analogues of murine epidermal. growth factor, [Abu6, 20] mEGF4-48 (where Abu denotes amino-butyric acid) and [G1, M3, K21, H40] mEGF1-48, have been investigated by NMR spectroscopy. [Abu6, 20] mEGF4-48 was designed to determine the contribution of the 6-20 disulfide bridge to the structure and function of mEGF The overall structure of this analogue was similar to that of native mEGF, indicating that the loss of the 6-20 disulfide bridge did not affect the global fold of the molecule. Significant structural differences were observed near the N-terminus, however, with the direction of the polypeptide chain between residues four and nine being altered such that these residues were now located on the opposite face of the main beta-sheet from their position in native mEGF Thermal denaturation experiments also showed that the structure of [Abu6, 20] mEGF4-48 was less stable than that of mEGF. Removal of this disulfide bridge resulted in a significant loss of both mitogenic activity in Balb/c 3T3 cells and receptor binding on A431 cells compared with native mEGF and mEGF4-48, implying that the structural changes in [Abu6, 20] mEGF4-48, although limited to the N-terminus, were sufficient to interfere with receptor binding. The loss of binding affinity probably arose mainly from steric interactions of the dislocated N-terminal region with part of the receptor binding surface of EGF [G1, M3, K21, H40] mEGF1-48 was also synthesized in order to compare the synthetic polypeptide with the corresponding product of recombinant expression. Its mitogenic activity in Balb/c 3T3 cells was similar to that of native mEGF and analysis of its H-1 chemical shifts suggested that its structure was also very similar to native.

Discovery and characterization of a family of insecticidal neurotoxins with a rare vicinal disulfide bridge

We have isolated a family of insect-selective neurotoxins from the venom of the Australian funnel-web spider that appear to be good candidates for biopesticide engineering. These peptides, which we have named the Janus-faced atracotoxins (J-ACTXs), each contain 36 or 37 residues, with four disulfide bridges, and they show no homology to any sequences in the protein/DNA databases. The three-dimensional structure of one of these toxins reveals an extremely rare vicinal disulfide bridge that we demonstrate to be critical for insecticidal activity. We propose that J-ACTX comprises an ancestral protein fold that we refer to as the disulfide-directed beta-hairpin.

Assessing the ex ante economic impacts of transportation infrastructure policies in Brazil

This paper uses a fully operational inter-regional computable general equilibrium (CGE) model implemented for the Brazilian economy, based on previous work by Haddad and Hewings, in order to assess the likely economic effects of road transportation policy changes in Brazil. Among the features embedded in this framework, modelling of external scale economies and transportation costs provides an innovative way of dealing explicitly with theoretical issues related to integrated regional systems. The model is calibrated for 109 regions. The explicit modelling of transportation costs built into the inter-regional CGE model, based on origin-destination flows, which takes into account the spatial structure of the Brazilian economy, creates the capability of integrating the inter-regional CGE model with a geo-coded transportation network model enhancing the potential of the framework in understanding the role of infrastructure on regional development. The transportation model used is the so-called Highway Development and Management, developed by the World Bank, implemented using the software TransCAD. Further extensions of the current model specification for integrating other features of transport planning in a continental industrialising country like Brazil are discussed, with the goal of building a bridge between conventional transport planning practices and the innovative use of CGE models. In order to illustrate the analytical power of the integrated system, the authors present a set of simulations, which evaluate the ex ante economic impacts of physical/qualitative changes in the Brazilian road network (for example, a highway improvement), in accordance with recent policy developments in Brazil. Rather than providing a critical evaluation of this debate, they intend to emphasise the likely structural impacts of such policies. They expect that the results will reinforce the need to better specifying spatial interactions in inter-regional CGE models.

The food business environment and the role of China and Brazil building a ""food bridge""

Purpose - The purpose of this paper is to discuss the economic crisis of 2008/2009 and the major impacts on developing nations and food-producing countries Within this macro-environment of food chains, there is concern that food inflation might come back sooner than expected The role of China as one of the major food consumers in the future, and Brazil, as the major food producer, is described as the food bridge, and an agenda of common development of these countries suggested. Design/methodology/approach - This paper reviews literature on muses of food inflation, production shortages, and investigation of programs to solve the problem in the future, it is also based on author`s personal insights and experience of working on this field in the last 15 years, and recent discussions in forums and interviews Findings - The major factors that jointly caused food prices increase in 2007/2008 were population growth, Income distribution, urbanization, dollar devaluations, commodity funds, social programs, production shortages, and bionic`s A list of ten policies is suggested. horizontal expansion of food production, vertical expansion, reduction in transaction costs, in protectionism and other taxes, investment in logistics, technology and better coordination, contracts, new generation of fertilizers and to use the best sources of biofuels. Originality/value - Two major outputs from this paper are the ""food demand model"" that inserts in one model the trends and muses of food inflation and the solutions, and the ""food bridge concept"" that also aligns in one box the imminent major food chain cooperation between China and Brazil

Copper-mediated amyloid-beta toxicity is associated with an intermolecular histidine bridge

Amyloid-beta peptide (A beta) is pivotal to the pathogenesis of Alzheimer disease. Here we report the formation of a toxic A beta-Cu2+ complex formed via a histidine-bridged dimer, as observed at Cu2+/ peptide ratios of > 0.6:1 by EPR spectroscopy. The toxicity of the A beta-Cu2+ complex to cultured primary cortical neurons was attenuated when either the pi- or tau-nitrogen of the imidazole side chains of His were methylated, thereby inhibiting formation of the His bridge. Toxicity did not correlate with the ability to form amyloid or perturb the acyl-chain region of a lipid membrane as measured by diphenyl- 1,3,5-hexatriene anisotropy, but did correlate with lipid peroxidation and dityrosine formation. P-31 magic angle spinning solid-state NMR showed that A beta and A beta-Cu2+ complexes interacted at the surface of a lipid membrane. These findings indicate that the generation of the A beta toxic species is modulated by the Cu2+ concentration and the ability to form an intermolecular His bridge.