Eucharist and Critical Metaphysics: A Response to Louis-Marie Chauvet's Symbol and Sacrament Drawing on the Works of Bernard Lonergan

Thesis advisor: Frederick G. LawrenceThis dissertation offers a critical response to the fundamental sacramental theology of Louis-Marie Chauvet drawing on the works of Bernard Lonergan. Chauvet has articulated a significant critique of the western theological tradition's use of metaphysics, especially in interpreting doctrines relating to the presence of Christ in the Eucharist, liturgical sacrifice, and sacramental causality. Chauvet's criticisms raise questions about what philosophical tools allow theologians to develop a fruitful analogical understanding of the mysteries communicated in the sacraments. This dissertation responds to Chauvet's challenge to theology to adopt a new foundation in the symbolic by turning to the derived, critical metaphysics of Bernard Lonergan. The dissertation argues that Lonergan's critical metaphysics can help theologians to develop fruitful understandings of doctrines relating to Eucharistic presence, liturgical sacrifice, and sacramental causality. In addition Lonergan's categories of meaning offer resources for interpreting sacramental doctrines on the level of the time, while maintaining the genuine achievements of the past. Chapter one presents a survey of some recent Catholic Eucharistic theologies in order to provide a context for our investigation. Here we identify existentialist-phenomenological, postmodern, and neo-traditionalist approaches to Eucharistic doctrines. Chapters two, three, and four present a dialectical comparison of Chauvet and Lonergan on metaphysics as it pertains to Eucharistic theology specifically. Chapter two examines Chauvet's postmodern critique of metaphysical foundations of scholastic Eucharistic theology. Our particular concern will be with Chauvet's methods, especially whether his appropriation of the Heideggerian critique of scholastic theology offers an accurate account of Thomas Aquinas, and whether it offers a fruitful way forward in Eucharistic theology. Chapter three explores Lonergan's foundations for metaphysics in cognitional theory and epistemology. Lonergan's critical groundwork in cognitional theory attends to the problems of bias and the polymorphism of human consciousness that lead to a heuristic metaphysics rather than a tidy conceptual system. Chapter four explicates Lonergan's heuristic metaphysics and articulates the elements of metaphysics that enable an understanding of the general category of causality in critical realist metaphysics. Chapter five explores Lonergan's foundations for theological reflection paying particular attention to the importance of intellectual conversion before going on to survey Lonergan's categories of meaning. Chapter six engages the task of systematic theology and proposes an understanding of Eucharistic doctrines grounded in Lonergan's critical realist philosophy and transposed into categories of meaning.Thesis (PhD) — Boston College, 2010.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Theology

SIV-specific CD8+ T cells are clonotypically distinct across lymphoid and mucosal tissues

CD8+ T cell responses are necessary for immune control of simian immunodeficiency virus (SIV). However, the key parameters that dictate antiviral potency remain elusive, conceivably because most studies to date have been restricted to analyses of circulating CD8+ T cells. We conducted a detailed clonotypic, functional, and phenotypic survey of SIV-specific CD8+ T cells across multiple anatomical sites in chronically infected rhesus macaques with high (>10,000 copies/mL plasma) or low burdens of viral RNA (<10,000 copies/mL plasma). No significant differences in response magnitude were identified across anatomical compartments. Rhesus macaques with low viral loads (VLs) harbored higher frequencies of polyfunctional CXCR5+ SIV-specific CD8+ T cells in various lymphoid tissues and higher proportions of unique Gag-specific CD8+ T cell clonotypes in the mesenteric lymph nodes relative to rhesus macaques with high VLs. In addition, public Gag-specific CD8+ T cell clonotypes were more commonly shared across distinct anatomical sites than the corresponding private clonotypes, which tended to form tissue-specific repertoires, especially in the peripheral blood and the gastrointestinal tract. Collectively, these data suggest that functionality and tissue localization are important determinants of CD8+ T cell–mediated efficacy against SIV

Ecosystem biogeochemistry considered as a distributed metabolic network ordered by maximum entropy production

Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of The Royal Society for personal use, not for redistribution. The definitive version was published in Philosophical Transactions of the Royal Society B 365 (2010): 1417-1427, doi:10.1098/rstb.2009.0272.We examine the application of the maximum entropy production principle for describing ecosystem biogeochemistry. Since ecosystems can be functionally stable despite changes in species composition, we utilize a distributed metabolic network for describing biogeochemistry, which synthesizes generic biological structures that catalyze reaction pathways, but is otherwise organism independent. Allocation of biological structure and regulation of biogeochemical reactions is determined via solution of an optimal control problem in which entropy production is maximized. However, because synthesis of biological structures cannot occur if entropy production is maximized instantaneously, we propose that information stored within the metagenome allows biological systems to maximize entropy production when averaged over time. This differs from abiotic systems that maximize entropy production at a point in space-time, which we refer to as the steepest descent pathway. It is the spatiotemporal averaging that allows biological systems to outperform abiotic processes in entropy production, at least in many situations. A simulation of a methanotrophic system is used to demonstrate the approach. We conclude with a brief discussion on the implications of viewing ecosystems as self organizing molecular machines that function to maximize entropy production at the ecosystem level of organization.The work presented here was funded by the PIE-LTER program (NSF OCE-0423565), as well as from NSF CBET-0756562, NSF EF-0928742 and NASA Exobiology and Evolutionary Biology (NNG05GN61G)

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

Influence of Prenatal Arsenic Exposure and Newborn Sex on Global Methylation of Cord Blood DNA

Background An emerging body of evidence indicates that early-life arsenic (As) exposure may influence the trajectory of health outcomes later in life. However, the mechanisms underlying these observations are unknown. Objective The objective of this study was to investigate the influence of prenatal As exposure on global methylation of cord blood DNA in a study of mother/newborn pairs in Matlab, Bangladesh. Design Maternal and cord blood DNA were available from a convenience sample of 101 mother/newborn pairs. Measures of As exposure included maternal urinary As (uAs), maternal blood As (mbAs) and cord blood As (cbAs). Several measures of global DNA methylation were assessed, including the [3H]-methyl-incorporation assay and three Pyrosequencing assays: Alu, LINE-1 and LUMA. Results In the total sample, increasing quartiles of maternal uAs were associated with an increase in covariate-adjusted means of newborn global DNA methylation as measured by the [3H]-methyl-incorporation assay (quartile 1 (Q1) and Q2 vs. Q4; p = 0.06 and 0.04, respectively). Sex-specific linear regression analyses, while not reaching significance level of 0.05, indicated that the associations between As exposures and Alu, LINE-1 and LUMA were positive among male newborns (N = 58) but negative among female newborns (N = 43); tests for sex differences were borderline significant for the association of cbAs and mbAs with Alu (p = 0.05 and 0.09, respectively) and for the association between maternal uAs and LINE-1 (p = 0.07). Sex-specific correlations between maternal urinary creatinine and newborn methyl-incorporation, Alu and LINE-1 were also evident (p\u3c0.05). Conclusions These results suggest that prenatal As exposure is associated with global DNA methylation in cord blood DNA, possibly in a sex-specific manner. Arsenic-induced epigenetic modifications in utero may potentially influence disease outcomes later in life. Additional studies are needed to confirm these findings and to examine the persistence of DNA methylation marks over time