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Executive Function Deficit as a Precursor to Memory Impairments in hApoE4 Transgenic Rats
Get PDFThe hApoE4 allele is one of the strongest genetic risk factors for Alzheimer’s disease (AD). It underlies amyloid-bdeposits and neurofibrillary tangles, the two hallmarks associated with AD pathology, and is subsequently associated with AD symptomology. Despite its importance, no rat animal studies to date use hApoE4 knock-ins. In addition to this deficit in the field of AD literature, the vast majority of AD studies focus on memory, even though executive function deficits may precede memory impairments in AD, and may be a predictor of AD development. Thus, the present study addressed these gaps in AD research by investigating the behavioral and physiological changes induced in rat models by an hApoE4 knock-in. hApoE4 rats experienced heightened anxiety compared to their wildtype counterparts, with male rats showing greater anxiety than females. hApoE4 rats had reduced motor capabilities, with males being disproportionately affected compared to females. Limited spatial learning and memory deficits were found at this time, but hApoE4 rats exemplified regressive behaviors in the probe trial of the spatial learning and memory task, indicating impairment in cognitive flexibility at this age. hApoE4 rats had impaired attentional set shifting abilities, with robust effects visualized in male hApoE4 rats. There was no difference in corticosterone levels between rats. Female hApoE4 rats were more sensitive to the hApoE4 knock-in compared to males, with more than half of the female hApoE4 rats failing to finish all measures due to the lethality of the knock-in. These results indicate that the hApoE4 knock-in effectively induced AD-like pathology in rat animal models, potentially to a lethal point in females. Executive function deficits appeared to precede spatial learning and memory deficits, indicating that future clinical interventions for AD should focus on identification of executive dysfunction
Where virtue goes: Stories
Get PDFThis story is a parallel narrative featuring the life in a fictional remote village in Vietnam some time during the 1800s, as well as the present-day life of a Vietnamese immigrant family in the US. The first narrative explores the efforts of a feminist duo, a matchmaker and a midwife, to help a young pregnant woman get out of an unhappy marriage. In doing so, the duo attempt to unravel traditional gender roles and oppressive social customs, and reweave the village social fabric. The other narrative explores a present-day marriage, one that is as much a disintegrating relationship as one evolving under severe duress of immigration to the US. This thesis hopes to ask and reflect on questions about family, partnership, loneliness, social belonging, duty, and individualistic vs. collectivistic cultures
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Get PDFDefend Free Speech on Campus, Learning About Life from Obituaries, Dinner with Milsy Was Formative-One Course at a Tim
Tyler Clevenger: Advancing Climate Policy at Home and Abroad
Get PDFI appreciated pretty early on that [climate] would represent my generation\u27s defining challenge, it would take the best that we as people have to offer. -Tyler Clevenger \u271
Sandy Buck \u2778: Seeing light Amidst the Gloom
Get PDFIf you look at the macro you could come to a grinding halt and throw your hand up. But when you look at the local, and even state and regional levels, there are reasons for hope. -Sandy Buck \u277
Gail Carlson: Inspiring Students to Step Up
Get PDFWhen you become a doomsday person, when you\u27re really pessimistic, it\u27s because you can\u27t see that you can make a difference. -Gail Carlson, associate professor of environmental studie
The Colby Echo (March 12, 2020)
No full textPublished by the students of Colby College since 1877, The Colby Echo is the weekly, editorially independent student-run newspaper of Colby College in Waterville, Maine. Published monthly, 1877-1886; semi-monthly, 1886-1897; and weekly, during the academic year, 1898-present.
Quantum Defect Measurements for High Angular Momentum Rydberg States of Potassium
No full textWe report measurements of the quantum defect for the f-, g-, and h-states of potassium with principal quantum number n between 26 and 29. Ground state potassium atoms in a magneto-optical trap are excited from the 4s state to the 5p state, then from the 5p state to the ndj state using lasers at 405nm and 980nm, respectively. We then measure the millimeter wave frequencies of the ndj to nl transitions. We extract the quantum defects from these frequency measurements in conjunction with the known d-state quantum defects. Experimental challenges with fully canceling the electric field and the inhomogeneity of the electric field inside the magneto-optical trap lead to our greatest sources of uncertainty. Our measurements show significant disagreement with predicted values that are calculated from the theoretical dipolar and quadrupolar polarizabilities of potassium