6. Performing Organization Code 7. Author(s)

Sacrificial shear keys are used at abutments to provide transverse support for bridge superstructures under seismic loads. In addition, sacrificial shear keys serve as structural fuses to control damage in abutments and the supporting piles under transverse seismic loads. Sacrificial shear keys may be interior or exterior. Exterior shear keys are usually recommended for new construction because they are easier to inspect and repair. One of the important issues addressed in this report is the post-earthquake inspection and repair of abutments with shear keys. This report presents the results of an experimental program that was performed at the University of California-San Diego (UCSD) to study the seismic response of interior and exterior sacrificial shear keys. The experimental program consisted of seven interior and six exterior shear keys experiments. Variables investigated during testing of the interior keys were: (1) loading protocol (monotonic, quasi-static reversed cyclic, and dynamic reversed cyclic), (2) geometric aspect ratio of the shear key, and (3) reinforcement ratio of the shear key. Variables investigated during testing of the exterior keys were: (1) inclusion of back and wing walls, (2) adoption of different key details such as the use of sacrificial flexural keys and construction joints between the abutment stem wall and the shear keys, and (3) post-tensioning of the abutment stem wall just below the shear keys. The experiment

Connection Of Concrete Barrier Rails To Frp Bridge Decks

The paper investigates the viability of use of conventional joining concepts between reinforced concrete barrier rails to fiber-reinforced polymer composite bridge decks. The concept is tested and implemented as part of a FRP bridge system incorporating concrete filled carbon/epoxy shells as girders and a pultruded core E-glass/vinylester-polyester deck. The barrier was anchored into the deck using polymer concrete filled cavities within the deck at discrete locations. Experimental results indicated that the configuration provides excellent anchoring capacity and a mode of failure that is more stable and capable of greater energy absorption than the conventional system due to the encapsulation of the anchorage within the composite deck. Failure was initiated through yield in the bars at a load of 129kN compared to a demand level of 44.5kN. No damage accrues to the deck itself with minimal damage in the anchorage. Analytical predictions of onset of yield and failure are shown to match experimental results as well. The testing validates the use of the system pursuant to specification mandated criteria. © 2004 Elsevier Ltd. All rights reserved

Enhanced anti-tumor immune responses and delay of tumor development in human epidermal growth factor receptor 2 mice immunized with an immunostimulatory peptide in poly(D,L-lactic-co-glycolic) acid nanoparticles.

IntroductionCancer vaccines have the potential to induce curative anti-tumor immune responses and better adjuvants may improve vaccine efficacy. We have previously shown that Hp91, a peptide derived from the B box domain in high-mobility group box protein 1 (HMGB1), acts as a potent immune adjuvant.MethodIn this study, Hp91 was tested as part of a therapeutic vaccine against human epidermal growth factor receptor 2 (HER2)-positive breast cancer.ResultsFree peptide did not significantly augment immune responses but, when delivered in poly(D,L-lactic-co-glycolic) acid nanoparticles (PLGA-NPs), robust activation of dendritic cells (DCs) and increased activation of HER2-specific T cells was observed in vitro. Vaccination of HER2/neu transgenic mice, a mouse breast cancer model that closely mimics the immune modulation and tolerance in some breast cancer patients, with Hp91-loaded PLGA-NPs enhanced the activation of HER2-specific cytotoxic T lymphocyte (CTL) responses, delayed tumor development, and prolonged survival.ConclusionsTaken together these findings demonstrate that the delivery of the immunostimulatory peptide Hp91 inside PLGA-NPs enhances the potency of the peptide and efficacy of a breast cancer vaccine