106 research outputs found

    PERFORMANCE OF ULTRA-THIN WHITETOPPING (UTW) IN OKLAHOMA

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    With the current level of deterioration of pavements in Oklahoma and the United States a satisfactory repair technique that is economical and can be applied rapidly while resisting a significant volume of traffic is becoming important. Thin concrete overlays have been used in increasing numbers over hot-mix asphalt (HMA) pavements and at intersections as a rapid and economical method of repair. These repairs have shown outstanding service in the state of Oklahoma with service lives over 10 years when used in areas with moderate truck traffic. These overlays are commonly referred to as white toppings as the overlay material is much lighter than the asphalt it is overlaying. This report is organized in three major sections. In section 2 the current condition of whitetopping projects is reviewed in Oklahoma. The inspection of these projects was primarily done with visual inspection, but some work was done with cores from the projects and also with Falling Weight Deflectrometer (FWD) measurements. In section 3 a review of the different whitetopping design methodologies is presented. In section 4 specific unanswered questions over whitetoppings are covered that the Oklahoma DOT felt were important to address from the existing literature.Final Report, October 2009-December 2010N

    DEVELOPMENT AND IMPLEMENTATION OF A MECHANISTIC AND EMPIRICAL DESIGN GUIDE (MEPDG) FOR RIGID PAVEMENTS — PHASE 2

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    The work investigates the impact of curing methods and their impact on subsequent curling in both the laboratory and the field in different drying environments. Results are also presented for a field instrumentation of a CRCP pavement in Tulsa, Oklahoma that uses a number of different curing methods. Next, a sensitivity analysis is completed for typical Oklahoma jointed and continuously reinforced pavements with different base friction parameters. Then the results from Darwin-ME are compared with field performance of CRCP and JPC pavements in Oklahoma. Finally, the shrinkage and coefficient of thermal expansion of concrete pavement mixtures are investigated with different past contents.Final report, October 2012-October 2014N

    Detecting the direction of a signal on high-dimensional spheres: Non-null and Le Cam optimality results

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    We consider one of the most important problems in directional statistics, namely the problem of testing the null hypothesis that the spike direction θ\theta of a Fisher-von Mises-Langevin distribution on the pp-dimensional unit hypersphere is equal to a given direction θ0\theta_0. After a reduction through invariance arguments, we derive local asymptotic normality (LAN) results in a general high-dimensional framework where the dimension pnp_n goes to infinity at an arbitrary rate with the sample size nn, and where the concentration κn\kappa_n behaves in a completely free way with nn, which offers a spectrum of problems ranging from arbitrarily easy to arbitrarily challenging ones. We identify various asymptotic regimes, depending on the convergence/divergence properties of (κn)(\kappa_n), that yield different contiguity rates and different limiting experiments. In each regime, we derive Le Cam optimal tests under specified κn\kappa_n and we compute, from the Le Cam third lemma, asymptotic powers of the classical Watson test under contiguous alternatives. We further establish LAN results with respect to both spike direction and concentration, which allows us to discuss optimality also under unspecified κn\kappa_n. To investigate the non-null behavior of the Watson test outside the parametric framework above, we derive its local asymptotic powers through martingale CLTs in the broader, semiparametric, model of rotationally symmetric distributions. A Monte Carlo study shows that the finite-sample behaviors of the various tests remarkably agree with our asymptotic results.Comment: 47 pages, 4 figure

    INVESTIGATION OF OPTIMIZED GRADED CONCRETE FOR OKLAHOMA - PHASE 2

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    Optimizing aggregate usage has been a subject widely discussed through the history of concrete. Since aggregates make up over 70% of the volume in a concrete mixture, the aggregate gradation is critical to the strength, workability, and durability of concrete. In practice, there is little quantitative guidance given to practitioners on aggregate proportioning in a mixture to meet the desired performance. The ACI 211 Mixture Design Procedure maybe the most widely taught mixture design method, but still is not widely used in practice due to limitations with the method. In fact, the ACI 211 method only contains a handful of aggregate parameters that many argue about the validity. One of the largest obstacles preventing the development of aggregate parameters and guidance comes from only a few test methods that are capable of providing quantitative data about the workability of concrete. This work focused on creating practical test methods and using them to understand how the aggregate gradation changes the workability of concrete.A series of workability tests for concrete were developed/used to investigate mixtures for bridge deck applications. Each test is used to evaluate various aggregate gradations and develop a new set of design recommendations and specifications.The ultimate product of this work is a new specification for the state of Oklahoma for mixtures with a greater durability at reduced cost and with improved sustainability. Based on 2015 production this design method has the potential to save the state of Oklahoma over $1.5 million per year, enough power for 440 Oklahoma homes, and reduce long term costs through reduced maintenance from durability issues.Final report, October 2013-October 2015N

    Use of a Novel Controlled Release Surface Curing Agent for Bridge Decks Phase 2

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    ODOT SPR Item Number 2258This report focuses on establishing methods to compare different curing methods and then determining how the timing of wet curing impacts the quality of the concrete in different evaporation environments. Chapter 2 uses electrical resistivity to non-destructively measure the moisture within concrete as it hydrates and correlates this to other measurements. Chapter 3 extends the electrical resistivity to evaluate how delays in the application of wet curing will impact the performance of bridge decks. The resistivity measurements provide new insights that are not easily obtained with other techniques and provide direct insights into the moisture change. The resistivity measurements over time are shown to correlate with the porosity, degree of saturation (DOS), and a novel tensile strength test. Chapter 4 provides an update on the use of Pulp Cure in the field and how modifications to the equipment can be used to make the application easier and more practical

    Phase II study of dacarbazine given with modern prophylactic anti-emetics and growth factor support to patients with metastatic, resistant soft tissue, and bone sarcoma

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    Historically, administration of dacarbazine to sarcoma patients was limited by frequent treat-ment-related nausea/vomiting and neutropenia. These toxicities are now largely preventable with contemporary antiemetics and growth factor support. In this single-arm, phase II study, dacarbazine 850 mg/m 2 was given on day 1 of each 3-week cycle until disease progression or intolerance with prophylactic serotonin-3 receptor, neurokinin-1 antagonists, corticosteroids, and pegfilgrastim. Coprimary endpoints included clinical benefit rate (CBR), and any grade of nausea/vomiting and/or grade 3–4 neutropenia. With a sample size of 80 patients, >24 patients with clinical benefit would indicate that the CBR exceeds the historical (<20%) [Power 0.80; alpha 0.05]. In addition, we hypothesized that the rates of nausea/vomiting would be 27% and grade 3–4 neutropenia would be 1% (historical: 90% and 36%, respectively) [power 0.95; alpha 0.05]. The CBR was 30% (24 patients: PR-2 and stable-22). The rate of nausea/vomiting was 37.5% (31 patients) and grades 3–4 neutropenia was 10% (8 patients). Median time-to-progression was 8.1 weeks (95% CI 8–9.7) and median overall survival was 35.8 weeks (95% CI 26.2–55.4). PET scans demonstrated no association with response. Modern prophylactic anti-emetics and pegfilgrastim given with dacarbazine reduced the rates of treatment related nausea/vomiting and serious neutropenia

    Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

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    In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field

    Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)

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