Pathophysiology of Myocardial Reperfusion Injury after Ischemia

An intricate look at the pathophysiology surrounding myocardial reperfusion injury and the implication is has on patient outcomes and nursing care

A Structural and Paleomagnetic Analysis of the Basalts of Summit Creek

This study is a detailed analysis of the structural geology and paleomagnetism of the Basalts of Summit Creek. Located southeast of Mount Rainier, this section of layered basaltic flows formed during the Eocene Epoch (55 to 45 Ma). The exact origin of the Basalts of Summit Creek is unknown, but there appears to be a growing connection between the Basalts of Summit Creek and the Crescent Basalts, which are Eocene flood basalts located on the Olympic Peninsula (Clark, 1989). This study attempts to provide a greater understanding of the emplacement and deformation of the Basalts of Summit Creek and any possible relationship with the Crescent Basalts. Once paleomagnetic directions were corrected for core orientation and bedding tilt, none of the flows yielded orientations consistent enough to provide reliable magnetic directions for the section. The scattered magnetic orientations are quite similar to those observed in the Crescent Basalts. This is does not demonstrate a definite connection between the two chemically similar Eocene volcanic sequences, but it does provide another similarity on the growing list. These two sections require further study to obtain the information needed to show a conclusive relationship beyond just their likeness in age, chemical and degree of alteration

Insights into the evolution of the Great Plains grassland ecosystem over the last 5 million years from paleotemperature and paleovegetation records

Over the last 10 million years, the Great Plains transitioned to the modern C4 grass dominated ecosystem. Well-preserved late Miocene to Holocene fossils and paleosols make the Meade Basin in southwest Kansas, USA a unique place to determine how paleoenvironmental conditions changed during C4 grassland evolution. δ18O values of paleosol carbonates (δ18Ocarb) in the Meade Basin decreased from the Miocene to Holocene while δ13C values increased; these trends were interpreted as an increase in temperature and/or in aridity coincident with an increase of C4 grass biomass on the landscape. Estimating temperature from δ18Ocarb is complicated, however, by the role of source water δ18O (δ18Owater) values in δ18Ocarb values. Thus, we used carbonate clumped isotope (Δ47) thermometry of paleosol carbonate nodules to develop independent paleotemperature estimates and estimated δ18Owater by combining temperature and δ18Ocarb values. Preliminary temperature estimates (5-1.8 Ma) in the Meade Basin range from 17°C to 24°C with no systematic change through time, when compared to the modern mean annual (14°C) and warm season (24°C) temperatures. In contrast, δ18Owater values increased through time. We preliminarily suggest that local/regional temperature change was not the primary factor that drove grassland ecosystem evolution in the Meade Basin, while increasing δ18Owater values suggest increased aridity may have been a bigger influence on C4 biomass and faunal changes, although we cannot rule out atmospheric CO2 (pCO2)changes. Additionally, Δ47 temperatures and δ18Owater values may reflect numerous factors besides air temperature and aridity changes, respectively, including depositional environment differences, soil type/depth, and source water changes. Further analyses and detailed organic biomarker records currently underway will help constrain the roles of paleoenvironmental factors in C4 grassland expansion

The Limits to Change in East Europe

What does every European need today? Provided peace and security are guaranteed, every European seeks to live in an open and prosperous society, in a society striving to put an end to injustice and capable of offering every individual the opportunity of making the most of his or her abilities while serving universal human ideals

Towards Global Justice: Reconciling Rawlsian Liberalism and Cosmopolitanism in an Interconnected World

In A Theory of Justice, John Rawls argues that, in constructing the basic structure of a just society, any social and economic inequalities must be part of a scheme of cooperation that works to the benefit of the least advantaged social class. He calls this principle of distributive justice the difference principle. In A Law of Peoples, however, he backs away from this claim, arguing for weaker cosmopolitan duties in constructing an international social order. This thesis does two things. 1.) It explores this tension in Rawls’s work, arguing that in order for the Law of Peoples to be consistent with A Theory of Justice, Rawls must embrace a global difference principle. 2.) It then investigates the implications of this conclusion, arguing that a global difference principle would necessitate robust duties of cosmopolitan aid, but would necessitate neither a world government nor open borders

Long term outcomes of on-pump CABG versus off-pump CABG

Objective: Assess the long-term outcomes including mortality, revascularization and myocardial infarction events to determine whether off-pump CABG is more effective for patients compared to on-pump CABG procedures. Methods: Studies were found using PubMed with the search term, “on and off pump CABG” which yielded 1736 studies. After assessing for records within 5 years the search was narrowed to 370 articles and then down to 353 because some articles were not available in full-text. Our search was then divided into first looking at randomized control trials and meta-analysis availability from the 353 articles meeting our criteria. After narrowing our search for only randomized control trials, we were left with 47 articles. We lastly went back to the 353 articles and narrowed that search to only available meta-analysis which gave us 27 options. The final studies were chosen based on their relation to our clinical question. Results: Studies show that there are no significant differences in the number of events sustained (or occurring) after both the off-pump CABG and on-pump CABG procedures. This was evident by results that varied between the three studies in which all percentages were close in number of events per population. Conclusion: In regard to deciding whether to perform on-pump CABG or off-pump CABG, the physician and patient need to make a joint decision based on the patient’s comorbidities and the physician’s experience as a surgeon. There is not conclusive evidence that one approach is more effective than the other

Master of Science

thesisVocal hyperfunction, characterized by excessive laryngeal muscle tension, is a condition associated with numerous voice disorders, including primary muscle tension dysphonia (pMTD). Primary MTD is disturbance occurring in the absence of structural or neurologic pathology. Vocal hyperfunction is postulated to be the proximal cause of the dysphonia in pMTD. A measure of relative fundamental frequency (RFF) has been proposed as an objective and noninvasive marker of vocal hyperfunction. This retrospective study examined the clinical utility of RFF in identifying and tracking changes in vocal hyperfunction before and following a course of manual circumlaryngeal therapy for pMTD patients. Because RFF is a time-based acoustic measure reliant on periodicity for accurate calculation, additional investigation into the influence of dysphonia severity on its validity across the severity spectrum was completed. RFF calculations were derived from pre- and posttreatment audio recordings from 111 females with pMTD and 20 vocally normal controls. Three voiced-voiceless stimuli (VCV tokens) were analyzed. Listener ratings of dysphonia severity were employed to determine (1) the relation of RFF measures to overall severity, and (2) the effects of dysphonia severity on the utility of RFF calculations. Multiple regression analyses demonstrated that RFF onset slope consistently varied as a function of group membership and therapy time conditions. Pearson Product-Moment Correlations showed a significant relationship between RFF onset cycle 1 values and listener ratings of dysphonia severity. In addition, regression analysis confirmed the influence of therapy condition and specific RFF cycles on dysphonia severity rating. Cumulatively, the analyses confirmed that RFF onset may be sensitive to predicting the presence and degree of vocal hyperfunction before and after therapy, and as an index of dysphonia severity. However, RFF could not be fully analyzed in many subjects, yielding a large quantity of missing data. Adjusted odds ratio estimates revealed that these unanalyzable data were related to phonetic context (token), group membership (pMTD vs. control) and severity level of dysphonia. Although RFF showed potential as an objective measure of vocal hyperfunction before and following voice therapy, the large number of unanalyzable samples (related to increased dysphonia severity especially in the pMTD group) represents a critical limitation

Paleoclimate and Paleoelevation Changes of The Western US During The Cretaceous

Terrestrial carbonates, like those that form in palustrine (wetland) and lacustrine (lake) settings, are important archives of climate and tectonics in the geologic past. However, they often preserve both primary depositional heterogeneity and secondary alteration. Stable isotope geochemistry and terrestrial sedimentology can be used to parse apart the effects of climate fluctuations and tectonic deformation recorded by these archives. For example, the Sevier Orogeny generated significant tectonic deformation in the western USA during the Cretaceous. It is unknown, however, when this region developed high surface elevations and how it responded to a global hothouse climate. I combine sedimentology and stable isotope geochemistry data from the mid-Cretaceous Newark Canyon Formation (NCF), Nevada to add to our understanding of paleoclimate during the Cretaceous and the timing and extent of surface uplift in the western USA (Figure 1-1). In Chapter 1, I explore the sedimentological evolution of the NCF and find that changes in the sedimentary style were principally driven by regional tectonic deformation caused by the on-going Sevier Orogeny rather than global climate changes (Fetrow et al., 2020). In Chapter 2, I generated &delta;13C, &delta;18O, &Delta;47, and &Delta;48 records to constrain the paleoclimate conditions of the mid-latitude western USA. As well, I explore the effects of diagenesis from hydrothermal fluids and possible dual clumped isotope (&Delta;48 vs &Delta;47) disequilibrium to evaluate which carbonate facies are representative of overall environmental conditions. The lower (~113&ndash;112 Ma) and the upper NCF type section (~112&ndash;103 Ma) preserve average warm season water temperatures of 41.3&deg;C (&plusmn; 3.6&deg;C, 2s.e.) and 37.7&deg;C (&plusmn; 2.5&deg;C, 2s.e), respectively. In Chapter 3, I use a subset of NCF geochemical data to estimate the paleoelevation of the NCF depositional basin. I compare ∆47 temperature and &delta;18Owater estimates from the NCF (~114 to 112 Ma) to those from the coeval, low elevation Cedar Mountain Formation (~118 to 117 Ma). Similar ∆47 temperatures and &delta;18Owater&nbsp;values between the two formations indicate that the Sevier hinterland had not experienced uplift by the mid-Cretaceous. These findings provide a critical boundary condition to the Sevier hinterland surface uplift history by confining uplift to the Late Cretaceous.</p