Wheaton College (MA) Digital Repository
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Analysis of the chemistry of making a leaded linseed oil paint.
No full textv, 36 leaves : illustrations (some color)Includes bibliographical references.Leaded linseed oils are a binder for oil paints used in the authentic restoration and conservation of traditional paintings. Analytical methods were used to investigate the color change which occurs during the 18-day preparation process in which the material becomes a drying oil suitable for application to works of art. Following an 18th century recipe, 5-10% leaded oil was created by heating linseed oil and lead oxide (PbO) and leaving the mixture to sit for 18 days, during which the material changed from dark brown to clear shades of yellow and orange. Samples created with this method were compared to samples created at the Hamilton Kerr Institute at the University of Cambridge, England. Samples were subjected to analysis by GC-MS, FT-IR, and UV-Vis. UV-Vis spectra indicate that the color change during preparation is attributed to a change in the conjugation patterns of the fatty acid components of the oil. These results are consistent with FT-IR data, which did not indicate any changes to the constitutional bonds of the fatty acids
Effects of Oxygen Deprivation on the Movement of Peripheral Neuron Growth Cones Harvested from Chicken Gallus gallus Embryos.
No full text8 pages; color illustrations.Includes bibliographical references
New way of war : the role of perception in counterinsurgency.
No full texti, 118 leaves.Includes bibliography: leaves 113-118.Defining terms -- Foundations of the U.S. counterinsurgency strategy -- Elements of counterinsurgency -- The U.S. counterinsurgency in Afghanistan -- The Chechen insurgency -- Comparison of case studies
Ciliogenesis during zebra fish heart regeneration.
No full text92 leaves : illustrations (some color).Includes bibliographical references: leaves 88-92.Cardiac ischemic injury, a heart attack, occurs when blood flow through the coronary arteries is obstructed. As a result in humans, necrotic tissue is replaced by hard, inelastic scar tissue that impairs the heart’s ability to function. The human heart possesses little to no regenerative capacity on its own to recovery from ischemic injury. Zebrafish, however, are capable of robust cardiac regeneration after injury to the heart. Through a series of remarkable heart-localized events that mirror embryonic development, the zebrafish can replace damaged or lost heart tissue within a month. We noticed the similarity between the regeneration and development of cardiac tissue may implicate cilia are involved during regeneration. Cilia are microtubule-based organelles that serve important sensory functions during embryonic development and organ homeostasis. It is well established that sensory cilia regulate Hedgehog and Wnt signaling pathways to aid in differentiating tissues during embryogenesis. Recent studies provide evidence that cilia are present during cardiogenesis and are necessary for proper cardiomyocyte differentiation and cardiac morphology. Thus, we hypothesized cilia may play similar roles during zebrafish heart regeneration. In the current study, we tested heart tissue for the presence of cilia using immunofluorescent confocal microscopy. Our preliminary data suggest cilia are abundant in regenerating cardiac tissue 7 days after removing a portion of the ventricular apex. In addition, we began to implement the surgical procedures necessary to injure the zebrafish ventricle at Wheaton College
Effects of Lithium on the Number of Connections Between Neurons and Glial Cells.
Get PDF9 pages; color illustrations.Includes bibliographical references