Incorporation and Characterization of Optical Oxygen Sensors in Silica Aerogel Monoliths

This thesis presents the preparation and spectroscopic characterization of silica aerogel monoliths containing one or more types of entrapped luminescent species. We are characterizing the response of aerogel-platform sensors to environments with varying amounts of oxygen and investigating whether it is possible to detect changes in luminescence signal based on the movement of oxygen through the aerogel monoliths. Our experiments indicate that for platinum(II) octaethylporphyrin (PtOEP) aerogels, the decrease in luminescence in the presence of oxygen is not linear with respect to the increase of concentration of oxygen. Various two-site models can be used to determine the accessibility of the PtOEP probes to oxygen. These techniques follow assumptions that the probes are located in two microenvironments, and either one or both of the microenvironments are accessible to oxygen. Data from both techniques indicate that the probes are accessible in only one microenvironment, with less than 10% inaccessible. PtOEP-doped silica aerogels can be fabricated up to 3 ½ x 3 ½ x ½ “, and luminescence is optically visible when oxygen is removed. The path of the luminescence can be tracked through the sample, indicating that it might be possible to determine the flow rate of gases through aerogels by monitoring the rate of appearance of luminescence

The Pathophysiological Role of Desmoglein 2 in a Stem Cell Model of Arrhythmogenic Right Ventricular Cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a progressive heart condition which causes ventricular arrhythmia, fibro-fatty myocardial scarring, and sudden cardiac death. The pathophysiology of ARVC is not well understood, particularly in early phases when arrhythmia can develop prior to structural changes. As a result, treatments for ARVC are limited and poorly targeted. The aim of this work was to generate a patient-derived induced pluripotent stem cell-derived cardiomyocyte (iPSC-CM) model of ARVC harboring a never-before-studied variant in DSG2 and apply it to glean insight into the roles that DSG2 and the variant of interest play in important pathophysiological questions surrounding ARVC. We created a novel iPSC-CM model of ARVC from a patient with a c.2358delA variant in desmoglein-2 (DSG2) and found that these DSG2-mutant cells displayed substantially altered action potentials and calcium transient dynamics. Mutant cells also displayed aberrant desmoglein-2 expression and atypical organization of contractile proteins. We also sought to generate an isogenic control for the novel ARVC line by using CRISPR-Cas9 to correct the mutant DSG2 allele. Despite passing all initial quality control checks, deep characterization of the edited cell line led to the discovery of hundreds of unexpected germline mutations, serving as a case study on the importance of thorough validation of new stem cell lines, particularly those that have undergone genome editing. An investigation into the effects of β-adrenergic signaling in our iPSC-CM model revealed that isoproterenol-induced effects on conduction and action potential upstroke observed in wildtype cardiomyocytes were dampened in DSG2-mutants and that DSG2 suppression in wildtype cells did not recapitulate these effects. Finally, we demonstrated that pro-inflammatory cytokines are much more highly expressed in DSG2-mutant iPSC-CMs, and that both canonical and noncanonical NFκB signaling pathways are highly activated in mutant cardiomyocytes compared to controls. We also found high levels of adipo-fibrokine expression in DSG2-mutants, which could reveal a link between cardiomyocyte signaling and fibro-fatty changes to the myocardium. In conclusion, our work suggests that differences in cellular electrophysiology, immune signaling, and response to β-adrenergic stimulation could all play important roles in ARVC pathophysiology. It also contributes new evidence that in vitro models of ARVC vary in their behavior significantly and underscores the challenge of defining ARVC in vitro in a way that is generalizable across models

Concord Companions: Margaret Fuller, Friendship, and Desire

In this paper, we examine the rhetoric of friendship and desire in mid-nineteenth-century American writing. We begin by looking at Emerson's essay on friendship and Thoreau's poem "Sympathy" (1840) to provide a context for reading Margaret Fuller's fascinating texts on samesex bonds between women. Of particular interest to us is Fuller's translation of Elizabeth von Arnim's Die Gunderode (1840), a collection of letters between Arnim and the German Romantic poet Karoline von Gunderode which provides compelling insights into the early to mid-nineteenth-century continuum between female friendship and same-sex desire. We situate this translation alongside Fuller's own female friendships and expressions of love for women, more specifically her declarations of love to Anna Barker and, later, to George Sand. This latter relationship, we suggest, was a source of admiration and anxiety, for Sand's cross-dressing and fluid sense of gender identity was simultaneously celebrated and condemned in Fuller's Women in the Nineteenth Century (1843)

Ihmeitten maassa: kreikkalaisia satuja N. Hawthornen mukaan

Kuvien signeeraus: RMMP.Pandora ja salaperäinen arkku ; Midas kuningas, joka muutti kullaksi kaiken, mihin vain kosketti ; Pegasos, siivekäs hevonen

Título: Cuadros proféticos

Texto paralelo inglés-españolP. tamen numeradas: [161]-19