Surface composition and structure of Co\u3csub\u3e3\u3c/sub\u3eO\u3csub\u3e4\u3c/sub\u3e(110) and the effect of impurity segregation

The Co3O4 (110) single crystal surface has been characterized by low energy electron diffraction (LEED), Auger electron spectroscopy, and x-ray photoelectron spectroscopy (XPS). LEED analysis of the clean Co3O4 (110) spinel surface shows a well-ordered pattern with sharp diffraction features. The XPS spectra are consistent with stoichiometric Co3O4 as determined by the concentration ratio of oxygen to cobalt (CO /CCo) and spectral peak shape. In particular, the cobalt 2p XPS spectra are characteristic of the spinel structure with Co3+ occupying octahedral sites and Co2+ in tetrahedral sites within the lattice. During prolonged heating at 630 K, bulk impurities of K, Ca, Na, and Cu segregated to the surface. Sodium desorbed from the surface as NaOH at 825 K, potassium and calcium were only removed by sputtering since no desorption from the surface was detected for temperatures up to 1000 K. Copper also disappeared upon heating above 700 K, most likely by desorbing although the possibility of diffusion back into the bulk could not be eliminated. The appearance of copper impurities correlated with Co3O4 (110) surface reduction to CoO, and the surface could not be fully reoxidized even upon extended oxygen annealing as long as the copper impurity remained on the surface. Upon removal of the Cu from the near-surface region, the surface was easily reoxidized to Co3O4 by O2

PTEN Depletion Decreases Disease Severity and Modestly Prolongs Survival in a Mouse Model of Spinal Muscular Atrophy.

Spinal muscular atrophy (SMA) is the second most common genetic cause of death in childhood. However, no effective treatment is available to halt disease progression. SMA is caused by mutations in the survival motor neuron 1 (SMN1) gene. We previously reported that PTEN depletion leads to an increase in survival of SMN-deficient motor neurons. Here, we aimed to establish the impact of PTEN modulation in an SMA mouse model in vivo. Initial experiments using intramuscular delivery of adeno-associated vector serotype 6 (AAV6) expressing shRNA against PTEN in an established mouse model of severe SMA (SMNΔ7) demonstrated the ability to ameliorate the severity of neuromuscular junction pathology. Subsequently, we developed self-complementary AAV9 expressing siPTEN (scAAV9-siPTEN) to allow evaluation of the effect of systemic suppression of PTEN on the disease course of SMA in vivo. Treatment with a single injection of scAAV9-siPTEN at postnatal day 1 resulted in a modest threefold extension of the lifespan of SMNΔ7 mice, increasing mean survival to 30 days, compared to 10 days in untreated mice. Our data revealed that systemic PTEN depletion is an important disease modifier in SMNΔ7 mice, and therapies aimed at lowering PTEN expression may therefore offer a potential therapeutic strategy for SMA

Unsayable Somethings: Modern American Poetry, Language, and the Logic of Experience

256 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2009.By exploring the categorical similarities between popular models of science, political economy, psychology, and sexuality, this dissertation addresses modern U.S. poetry's obsession with conjuring the unsayable. Chapters 1 and 2 explore the social and conceptual landscape that came to align the sayable with the cognitive and credible, while relegating alternative ways of knowing to the category of the unsayable. For various American poets, non-cognitive modes of knowing---in the form of intuitions and gut instincts---are given a palpable resonance in the articulation of experiences of race, gender, nation, class, and sexuality in the early 20th century. Chapter 3 illustrates how the speaker in Mina Loy's Love Songs to Joannes (1917) shows that the emergent scientific paradigms of the time shut down not only the possibility for acknowledging intuitions, but also the possibilities for person-to-person intimacy. Chapter 4 argues that in the poetries of Sterling Brown and Edwin Rolfe, articulations of laughter and music, and representations of workers' bodies, respectively, point to the important role that the sayable plays in maintaining structures of dominance in the U.S., specifically with respect to the slew of constitutional race and work laws created and reformulated during the period of modernity. Chapter 5 demonstrates the ways in which the paradoxical representations of lesbian desire in the poetries of Amy Lowell and Angelina Weld Grimke's negotiate the sayable and unsayable; as such, they are put into relief by differently complex experiences of embodiment and the power dynamics at play in relationships that at times cannot, and at other times must not, be articulated.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD