1,766 research outputs found
Characterization of Alaskan Hot-Mix Asphalt containing Reclaimed Asphalt Pavement Material
In order to properly characterize Alaskan HMA materials containing RAP, this study evaluated properties of 3 asphalt binders typically used in Alaska, PG 52-28, PG 52-40, and PG 58-34, and 11 HMA mixtures containing up to 35% RAP that were either produced in the lab or collected from existing paving projects in Alaska. Various binder and mixture engineering properties were determined, including true high binder grades, complex modulus (|G*|), and phase angle (δ) at high performance temperatures, MSCR recovery rate and compliance, BBR stiffness and m-value, DTT failure stress and strain for binders, and dynamic modulus, flow number, IDT creep stiffness and strength for mixtures. Binder cracking temperatures were determined through Thermal Stress Analysis Routine (TSAR) software along with BBR and DTT data. Mixture cracking temperatures were determined with IDT creep stiffness and strength data. It was found that rutting may not be a concern with Alaskan RAP mix, while low-temperature cracking concerns may still exist in RAP mix in Alaska. A savings of $13.3/ton was estimated for a 25% RAP mix, with consideration of Alaskan situations. Many recommendations for future RAP practice and research are recommended based on testing results and cost analysis.Alaska Department of Transportation Statewide Research Offic
Performance of TenCate Paving Interlayers in Asphalt Concrete Pavements
As a continued effort of a previously completed project entitled “Performance of TenCate Mirafi PGM-G4 Interlayer-Reinforced Asphalt Pavements in Alaska,” this project evaluated two newly modified paving interlayers (TruPave and Mirapave) through overlay, dynamic modulus tests and low-temperature performance tests. A field survey was conducted to further evaluate the performance of three paving interlayers (G4, G50/50, and G100/100) applied to field sections constructed in May 2013 at Milepost 148–156 Richardson Highway in Alaska. Overlay test results indicate that asphalt concrete (AC) with paving interlayers (TruPave and Mirapave) shows lower reduction in peak load, suggesting better cracking resistance. The dynamic modulus measurement of AC with paving interlayers reveals more rational results from the IDT mode test than the AMPT method due to similar stress conditions in the paving interlayer. With paving interlayers, the temperature sensitivity and cracking potential of AC material were reduced according to the results from the IDT creep test. Field survey results confirm that all sections reinforced with paving interlayers (G4, G50/50, and G100/100) had better cracking resistance than the control section.TenCate Geosynthetics North Americ
Analysis of the Effects of Active Immunization with Aβ1-42 Peptide of APPPS1 Transgenic Mice at Three and Nine Months of Age
From the Washington University Office of Undergraduate Research Digest (WUURD), Vol. 13, 05-01-2018. Published by the Office of Undergraduate Research. Joy Zalis Kiefer, Director of Undergraduate Research and Associate Dean in the College of Arts & Sciences; Lindsey Paunovich, Editor; Helen Human, Programs Manager and Assistant Dean in the College of Arts and Sciences Mentor(s): Anne Faga
Poetics of Cross-Cultural Relation: Critical Performances by Artists kate-hers RHEE and Patty Chang
This article explores anti-racist, feminist performance and video art by kate-hers RHEE and Patty Chang. Parodic performances of awkward sexual encounters in works such as RHEE’s The Chocolate Kiss (2013) and Chang’s The Product Love (2009) embody and deconstruct identity formation within transnational German and Asian American contexts. I explore how RHEE and Chang distinctly challenge sexist and racist stereotypes and the objectification of Asian women, while problematizing cultural categorization through (mis)translations and poetic relations. The article illuminates how these artists complicate Asian American identities via variegated explorations of critical race theories and connected histories of cross-cultural representation
Development of Targeted Pro-Angiogenic Therapies for Ischemic Diabetic Foot Ulcer Repair
Between 15-25% of diabetic patients develop chronic foot ulcers within their lifetime. These ulcers are characterized by delayed wound healing, are highly susceptible to infection, and can lead to lower-limb/foot amputation. Impaired ulcer healing is most often due to ischemia and insufficient formation of new vessels in the wound bed, as well as rapid turnover of healing tissue by excessive matrix metalloproteinase (MMP) activity. To improve healing of chronic ischemic wounds, researchers have sought to increase angiogenesis at the wound site using growth factors such as vascular endothelial growth factor (VEGF). VEGF is a key angiogenic mediator and uniquely participates in multiple aspects of wound healing including revascularization, reepithelialization, and collagen deposition. However, the clinical success of growth factor therapies such as VEGF has been limited largely due to the overexpression MMPs in the wound environment that degrade or inactivate the growth factors. Furthermore, non-targeted angiogenic growth factor therapies raise significant concerns because they are not restricted to the wound site, but potentially diffuse into systemic circulation and cause malignancies. This thesis reviews current advances in understanding the pathogenesis and pathophysiology of the compromised wound healing environment leading to DFUs with particular emphasis on the roles of neovascularization and matrix remodeling. It also addresses recent progress in VEGF therapy for DFUs and the current limitations in clinical translation imposed by co-existing pathophysiological defects of diabetic wound healing. Given the current understanding of the impaired healing components suggesting a need to correct multiple derangements while maintaining efficacy in the complex and highly proteolytic environment, we propose multiple collagen-targeted, degradation resistant, proangiogenic therapies to activate and potentiate VEGF pathways and simultaneously protect existing collagen matrices. Specifically, we discuss the development of VEGF-loaded collagen-binding nanoparticles and two variants of engineered decorin mimetics functionalized with pro-angiogenic VEGF-mimicking or αvβ3 integrin-binding peptides to increase vascularization of the wound bed. Both the nanoparticles and the angiogenic proteoglycan mimics can be targeted to endogenous collagen or exogenous collagen dressings by a collagen-binding peptide and could be used in combination to exploit VEGF activation and potentiation. This project (i) develops a thermosensitive nanoparticle VEGF-delivery system, (ii) develops and characterizes pro-angiogenic peptide-functionalized decorin mimics, and (iii) assesses the in vitro and in vivo angiogenic potential of these pro-angiogenic decorin mimics as proof-of-concept supporting their potential to accelerate ischemic dermal wound healing in animal models
Analysis of long-term opioid prescribing practices in cancer patients at a pediatric tertiary institution
INTRODUCTION: Pain is common in cancer. Pain can present at the time of diagnosis or it can develop during treatment. Cancer-related chronic pain is often treated with long-term (3 or more consecutive refills) opioid prescriptions. Opioids are a controlled substance and are thus regulated at the federal, state, and local levels.
OBJECTIVES: The first goal of this study is to examine Boston Children's Hospital's general compliance with federal, state, and local opioid prescribing policies. The second goal of this study is to distinguish cancer patients requiring long-term opioids from non-cancer patients requiring long-term opioids.
METHODS: This study was a retrospective chart review using summative qualitative content analysis. This is the process where content is grouped into themes and then is further quantified within each theme.
RESULTS: Documents required to ensure compliance with opioid prescribing regulations at the local level are not always well documented. These include the Long-Term Opioid Agreement and the risk evaluation of opioid misuse and abuse using one of several tools annually. At Boston Children's Hospital (BCH), the CRAFFT (car, relax, alone, forget, friends, trouble) questionnaires are used for this purpose. State policies require that, if a patient is not seen at least once every 6 months, physicians must document explicitly why a clinic visit was not possible. These reasons are never clearly listed within the medical record. Additionally, data shows that cancer patients using long-term opioids tend to be younger (mean age 14.4) than non-cancer patients (mean age 26.7). Cancer pain can present either at diagnosis, during treatment, or be present during both. Where n=16 cancer patients, 62.53% experienced pain both at diagnosis and during treatment, 25% experienced pain only during treatment, and 12.5% experience pain only at diagnosis. Finally, data also show that anxiety and comorbidity are common, 34.6% of n=29 patients in both cancer and non-cancer patients using long-term opioids. 34.6% of patients experienced comorbidities of either anxiety or depression.
CONCLUSIONS: Despite these discrepancies with documentation, review of patients on long-term opioids revealed those with complex and painful medical conditions generally had valid reasons to require long-term opioids. Therefore, there is no evidence that BCH prescribers are involved in any sort of inappropriate opioid prescribing. Finally, no meaningful conclusions were drawn from data regarding pain score and weight because of inconsistencies in electronic medical record documentation in these areas
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