Browsing by Subject "aluminum"

Now showing 1 - 3 of 3
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    Aluminum Effects in Infants and Children
    (AAP, 2019-12) Corkins, Mark R.; Abrams, Steven A.; Fuchs, George J.; Goday, Praveen S.; Hannon, Tamara S.; Kim, Jae H.; Lindsey, C. Wesley; Rome, Ellen S.; Pediatrics, School of Medicine
    Aluminum has no known biological function; however, it is a contaminant present in most foods and medications. Aluminum is excreted by the renal system, and patients with renal diseases should avoid aluminum-containing medications. Studies demonstrating long-term toxicity from the aluminum content in parenteral nutrition components led the US Food and Drug Administration to implement rules for these solutions. Large-volume ingredients were required to reduce the aluminum concentration, and small-volume components were required to be labeled with the aluminum concentration. Despite these rules, the total aluminum concentration from some components continues to be above the recommended final concentration. The concerns about toxicity from the aluminum present in infant formulas and antiperspirants have not been substantiated but require more research. Aluminum is one of the most effective adjuvants used in vaccines, and a large number of studies have documented minimal adverse effects from this use. Long-term, high-concentration exposure to aluminum has been linked in meta-analyses with the development of Alzheimer disease.
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    Numerical simulation of aluminum extrusion using coated die
    (2014) Bakhtiani, Tushar; El-Mounayri, Hazim; Zhang, Jing
    In aluminium extrusion, the life of the die tooling components is mainly limited by wear and fatigue. Therefore reliable predictions of the amount of wear and its distribution in dies are important factors for the die design. In this study the stress location and wear depth of the tooling components were calculated using finite element models incorporating the Archards wear model. A comparative study was conducted on an extrusion die without coating and with a bilayer (TiCN + Al2O3) chemical vapor deposition (CVD) coating. Stress distribution and the amount of wear were calculated. The results generated from the simulation would help predict the service life of the components through optimizing coating thickness.
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    The role of SMF 1, SMF-2, SMF-3 in metal-induced whole animal vulnerability and dopamine neuron degeneration in Caenorhabditis elegans
    (2012-12-04) LeVora, Jennifer K.; Nass, Richard M.; Nicol, Grant D.; Hingtgen, Cynthia M., 1966-
    The etiology of many neurodegenerative diseases is unknown, but a number of studies indicate that a combination of both genetic and environmental factors contribute to the progression of disease. Exposure to environmental metals, such as Mn2+, Fe2+, Cu2+, and Al3+, has been shown to increase cell death that is characteristic of neurodegenerative disorders such as AD, PD, Wilson’s disease and Menkes disease. These metals are important in numerous biological processes in the brain and their homeostasis is regulated through multiple mechanisms of transport, storage, and secretion. The vertebrate divalent metal transporter-1 (DMT-1) has been implicated in transport and homeostasis of these divalent cations. In these studies I utilize Caenorhabditis elegans (C. elegans) to show that long term exposure to Mn2+ decreases animal viability in a dose-dependent manner, and I demonstrate that C. elegans homologues to DMT-1, SMF-1, SMF-2, and SMF-3, play specific roles in divalent metal ion-induced DA neurodegeneration. I show that SMF-1 contributes to Fe2+-induced DA neuron degeneration, SMF-3 contributes to Al3+-induced DA neuron degeneration, and both SMF-2 and DAT-1 contribute to Cu2+-induced DA neuron cell death. These studies utilize C. elegans as a powerful model to characterize molecules and pathways involved in metal toxicity and metal-induced DA neuron degeneration.