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Life with God - human participation in eternal communion : the status of the theological anthropology of John D. Zizioulas
No full textThis thesis considers the high theological anthropology of John Zizioulas and offers the first through examination of his doctrine of humanity. He grounds his theology with pneumatological Christology, so to hear him accurately, we must understand that Jesus Christ does not simply repair humanity’s fallen condition but rather reveals God’s plan for his cosmos. For Zizioulas, theology must be understood eschatologically with the local church standing as the living icon of God’s eternal people. As such, his holistic account of mankind restates in contemporary terms what the catholic Church has agreed on. Simply put, Jesus Christ reveals God’s eternal public which the Church’s worship expectantly displays. So, this thesis critically assesses Zizioulas’ anthropology articulated in terms of relational ontology to demonstrate that his holistic expression is an integrated synthesis of the catholic tradition instead of a theological innovation. Further, the thesis aspires to show that his work brings together the reception’s many contributions and that Jesus Christ preserves God-man koinōnia. In this way, Zizioulas’ anthropology seeks to articulate and offer the Eastern Church’s metaphysical realism to the whole Church because he believes this conceptuality best communicates the life that God offers humankind as created persons. This thesis, then, is an exercise to consider whether Zizioulas’ integrated theology can strengthen humankind’s knowledge of Christ’s metaphysical revolution. As an ecumenist, Zizioulas aims to build unity among the Church’s many traditions and promote God’s good intention towards humankind. Moreover, he sees the present generation’s struggle for identity as resulting from individual attempts to fabricate purpose from pejorative and reductionist theories of mankind. Consequently, Zizioulas’ theological anthropology offers a positive voice to the anthropological discourse by arguing not only that God alone offers human integers lasting communion as the named members of Trinity’s consummate kingdom, but also that the worshipping Church’s many assemblies make this end partially visible today
Combinatorial algorithms in semigroups
Get PDFComputational semigroup theory is concerned with developing and implementing algorithms for determining properties of semigroups. The problems in computational semigroup theory can often be divided into sub-problems in computational group theory and combinatorics. In this thesis, we demonstrate how to split a number of problems into group-theoretical and combinatorial sub-problems, and provide algorithms for solving the combinatorial sub-problems. The algorithms presented in this thesis have been implemented in C++ and GAP, and benchmarks are provided to show them practical.
In Chapter 1, we introduce the necessary background in semigroup theory.
In Chapter 2, we introduce a new algorithm for non-exhaustively determining the structure of a semigroup defined by generators, and show that it applies to certain families of matrices over semirings as well as a number of standard and well-known families to which previous algorithms apply.
In Chapter 3 we describe and compute minimal generating sets for several naturally occurring monoids of boolean matrices, in particular the full boolean matrix monoid, Hall monoid, reflexive boolean matrix monoid, and upper and lower triangular boolean matrix monoids. These results extend the dimensions for which the ranks of these monoids are known. We also determine the rank of the 2 × 2 matrices over the max-plus and min-plus semirings with and without threshold, as well as the n × n matrices over ℤ/kℤ relative to their group of units.
Chapter 4 contains new algorithms for determining the translations and bitranslations of arbitrary finite semigroups. We also provide specialised algorithms for computing translations and bitranslations of semigroups defined by finite presentations, completely 0-simple semigroups, congruence-free semigroups, and completely-simple semigroups.
Finally, Chapter 4 contains some further questions raised by the work in this thesis
Toward a Cenozoic history of atmospheric CO2
Get PDFFunding: This work was supported by National Science Foundation grant OCE 16-36005 (B.H. and P.J.P.), Heising-Simons Foundation grant 2018-0996 (B.H. and V.F.), National Science Foundation grant EAR 21-21649 (B.H., V.F., J.J.M., and C.F.G.), National Science Foundation grant EAR 21-21170 (G.J.B.), National Science Foundation grant EAR 20-02370 (Y.C.), National Science Foundation grant 18-43285 (A.P.), Columbia University’s Center for Climate and Life (K.T.U.), the G. Unger Vetlesen Foundation (K.T.U.), National Science Foundation grant 21-00537 (A.P. and P.J.P.), National Science Foundation grant 21-00509 (P.J.P.), National Science Foundation grant EAR 21-21165 (A.R.), National Science Foundation grant EAR 18-06015 (Y.G.Z.), National Science Foundation grant DGE 16-44869 (S.R.P.), National Science Foundation grant 18-13703 (E.G.H.), National Science Foundation grant OCE 16-58023 (J.C.Z.), National Science Foundation grant 16-02905 (M.H.), Swedish Research Council grant NT7-2016 04905 (M.S.), European Research Council grant 101020824 (J.C.M.), SFI/RC/2092 (J.C.M.), UK Research and Innovation grant 101045371 (M.J.H.), Natural Environment Research Council grant NE/X000567/1 (M.P.S.B.), Royal Society grant DHF\R1\221014 (C.R.W.), Australian Research Council grant DP150104007 (P.J.F.), Deutsche Forschungsgemeinschaft grant RA 2068/4-1 (M.R.), European Research Council grant 805246 (J.W.B.R.), an ETH Fellowship (J.K.C.R.), National Science Foundation of China grant 42030503 (J.D.), the Sandal Society Museum (G.J.R.), a Royal Society Tata Fellowship (B.D.A.N.), and Natural Environment Research Council grant NE/P019048/1 (G.L.F.).INTRODUCTION Anthropogenic carbon dioxide (CO2) emissions have driven an increase in the global atmospheric CO2 concentration from 280 parts per million (ppm) before industrialization to an annual average of 419 ppm in 2022, corresponding to an increase in global mean surface temperature (GMST) of 1.1°C over the same period. If global CO2 emissions continue to rise, atmospheric CO2 could exceed 800 ppm by the year 2100. This begs the question of where our climate is headed. The geologic record is replete with both brief and extended intervals of CO2 concentration higher than today and thus provides opportunities to project the response of the future climate system to increasing CO2. For example, it has been estimated that global surface temperature 50 million years ago (Ma) was ~12°C higher than today, in tandem with atmospheric CO2 concentrations some 500 ppm higher (i.e., more than doubled) than present-day values. Consistent with these estimates, Antarctica and Greenland were free of ice at that time. However, reconstructing these values prior to direct instrumental measurements requires the use of paleoproxies—measurable properties of geological archives that are closely, but only indirectly, related to the parameter in question (e.g., temperature, CO2). To date, at least eight different proxies from both terrestrial and marine archives have been developed and applied to reconstruct paleo-CO2, but their underlying assumptions have been revised over time, and published reconstructions are not always consistent. This uncertainty complicates quantification of the climate responses to the ongoing rise of atmospheric CO2 concentrations. RATIONALE Although earlier studies have compiled published paleo-CO2 estimates, those studies typically applied only limited proxy vetting, included estimates that were made before the proxies were sufficiently validated, and/or focused on only a subset of available proxy data. The international consortium of the Cenozoic CO2 Proxy Integration Project (CenCO2PIP) has undertaken a 7-year effort to document, evaluate, and synthesize published paleo-CO2 records from all available archives, spanning the past 66 million years. The most reliable CO2 estimates were identified, some records were recalculated to conform with the latest proxy understanding, age models were updated where necessary and possible, and data were categorized according to the community’s level of confidence in each estimate. The highest-rated data were eventually combined into a reconstruction of the Cenozoic history of atmospheric CO2. RESULTS The resulting reconstruction illustrates a more quantitatively robust relationship between CO2 and global surface temperature, yielding greater clarity and confidence than previous syntheses. The new record suggests that early Cenozoic “hothouse” CO2 concentrations peaked around 1600 ppm at ~51 Ma. Near 33.9 Ma, the onset of continent-wide Antarctic glaciation coincided with an atmospheric CO2 concentration of 720 ppm. By ~32 Ma, atmospheric CO2 had dropped to 550 ppm, and this value coincided with the onset of radiation in plants with carbon-concentrating mechanisms that populate grasslands and deserts today. CO2 remained below this threshold for the remainder of the Cenozoic and continued its long-term decrease toward the present. Along this trajectory, the middle Miocene (~16 Ma) marks the last time that CO2 concentrations were consistently higher than at present; Greenland was not yet glaciated at that time, and independent estimates suggest that sea level was some 50 m higher than today. Values eventually dropped below 270 ppm at the Plio-Pleistocene boundary (2.6 Ma), when Earth approached our current “icehouse” state of bipolar glaciation. This and other climatic implications of the revised CO2 curve, including the evolution of the cryosphere, flora, and fauna, along with the cross-disciplinary data assessment process, are detailed in the full online article. CONCLUSION This community-vetted CO2 synthesis represents the most reliable data available to date and a means to improve our understanding of past changes in global climate and carbon cycling as well as organismal evolution. However, this effort is still incomplete. Data remain sparse during the earlier part of the record and in some instances are dominated by estimates from a single proxy system. Generating a paleo-CO2 record with even greater confidence will require further research using multiple proxies to fill in data gaps and increase overall data resolution, resolve discrepancies between estimates from contemporaneous proxy analyses, reduce uncertainty of established methods, and develop new proxies.Peer reviewe
Assessing the role of geographical access to health-care in colorectal cancer diagnosis and survival in Scotland
No full textGeographical accessibility to healthcare services is important for the achievement of health equity. Lack of spatial access can result in delayed medical treatment and poor health outcomes. In this research, individual level data are used to assess how geographical accessibility to healthcare influences cancer diagnosis and survival in Scotland. Specifically, this thesis aims to address the following three research questions:
• How does geographical accessibility to healthcare services vary according to area characteristics?
• Is geographical accessibility to cancer treatment hospitals associated with rates of colorectal cancer survival?
• Is geographical accessibility to General Practitioners (GPs) associated with the stage of diagnosis for colorectal cancer?
To address the above research questions, this thesis develops a new Geographic Information System (GIS) measure of distance and time to health services at a fine-scale geography (i.e., postcode level) in Scotland. Three other major datasets are innovatively linked with the GIS- based accessibility measure to explore colorectal cancer diagnosis and survival in the Scottish context; these are the Scottish Longitudinal Study, NHS National Services Scotland, and Scottish Government data. This research found significant variation in travel time to GP and hospitals in Scotland at postcode level. After controlling for rurality, there is an area-level social gradient in distance to health services. Using survival analysis modelling and controlling for other social, demographic and economic correlates of diagnosis and survival for colorectal cancer, this thesis found that travel time to health services has no influence on colorectal cancer diagnosis or survival in Scotland. Unlike many previous studies, this study controlled for individual correlates of social circumstances. Early diagnosis, screening and having early treatment were found to be significant in determining cancer survival. The use of individual level data and the linkage of four major national datasets have opened new avenues for future health research to test hypotheses about geographical accessibility in other cancers."This PhD study is fully funded by the University of St Andrews, School of Geography and Sustainable Development (600th Anniversary Scholarship) to which we are deeply thankful."--Fundin
Alfvén-fast wave coupling in a 3D non-uniform medium
No full textFunding; The authors acknowledge financial support by the UK’s Science and Technology Facilities Council (STFC). R.D. was supported by STFC Doctoral Training Partnership Grant No. ST/T506436/1. A.N.W. was partially supported by STFC Grant No. ST/W001195/1.In this paper, we consider the process of Alfvén-fast wave mode coupling, through numerical simulation. We model the process using the ideal, linear magnetohydrodynamic equations on a three-dimensional Cartesian grid; assuming the cold plasma limit, β≪1. We initialize the simulation with a cylindrical Alfvén wave pulse (comprising an azimuthal magnetic field and velocity perturbations) propagating along a uniform magnetic field. The wave starts in a region where the density is uniform. As it propagates, part of the Alfvén wave encounters a change in density, before emerging into a second uniform region. We introduce the natural Helmholtz Hodge decomposition as a method to identify the properties of the Alfvén wave perturbations at the end of the simulation. Our results show that the Alfvén wave propagates efficiently through the non-uniform region, with the wave pulse's final structure sharing strong characteristics of the initial wave pulse structure. More than 69% of the initial energy is carried by the transmitted Alfvén wave. Alfvén-fast wave coupling has potential applications in planetary magnetospheres, such as in the Io-Jupiter Alfvén wave interaction, and the solar corona.Peer reviewe
Recognizing intentional signals and their meaning in non-human communication
Get PDFHow can we tell if someone is trying to talk to us—especially when that someone is not a member of our species (or even from our solar system)? And once we have detected a signal, how can we tell what it means? This chapter outlines an approach based on the work of the twentieth-century philosopher Paul Grice. It begins by developing two key ideas from Grice: (i) the idea that communication is a cooperative endeavor, and (ii) the idea that meaning (in one interesting sense) is a matter of acting with particular intentions. It then shows how these two ideas have been developed into a toolkit that has proved very fruitful in studying non-human animal communication. Applying this toolkit to extraterrestrial signals would be challenging, but the chapter concludes by suggesting strategies with which to begin
Evolution of phenotypic plasticity leads to tumor heterogeneity with implications for therapy
Get PDFFunding: SS and AD are funded by the European Union (ERC, subLethal, 101054921, https://erc.europa.eu/). SS and AD acknowledge support by Worldwide Cancer Research (23-0177, https://www.worldwidecancerresearch.org). HPJ acknowledges support by the European Union’s Horizon 2020 research and innovation programme (CompSci TraCS, 945371, https://cordis.europa.eu). HH thanks Volkswagenstiftung for its support in the "Life?" program (96732, https://www.volkswagenstiftung.de). He has received funding from the Bundesministerium für Bildung und Forschung under grant agreement No. 031L0237C (MiEDGE project/ERACOSYSMED, https://www.bmbf.de). He also acknowledges the support of the RIG-2023-051 grant from Khalifa University (https://www.ku.ac.ae) and the AJF-NIH-25-KU grant from the NIH-UAE collaborative call 2023 (https://www.aljalilafoundation.ae).Author summary Intratumor heterogeneity presents a significant barrier to effective cancer therapy. This heterogeneity stems from the evolution of cancer cells and their capability for phenotypic plasticity. However, the interplay between these two factors still needs to be fully understood. This study examines the interaction between cancer cell evolution and phenotypic plasticity, focusing on the phenotypic switch between migration and proliferation. Such plasticity is particularly relevant to glioblastoma, the most aggressive form of brain tumor. By employing a novel model, we explore how tumor cell evolution, influenced by both genotype and microenvironment, contributes to tumor heterogeneity. We observe that cells at the tumor periphery tend to migrate, while those within the tumor are more inclined to proliferate. Interestingly, our analysis reveals that distinct genetic configurations of the tumor can lead to this observed pattern. Further, we delve into the implications for cancer treatment and discover that it is phenotypic, rather than genetic, heterogeneity that more accurately predicts tumor recurrence following therapy. Our findings offer insights into the significant variability observed in glioblastoma recurrence times post-treatment.Peer reviewe
A women ambassador behind the scenesRosario Castellanos in Israel (1971-1974)
No full textPeer reviewe
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