Application of the Kihara core model equation to gas-solid interactions

M.S.Robert A. Pierott

Sextus was no Eudaimonist

Ancient Greek philosophical schools are said to share a common structure in their ethical theories which is characterized by a eudaimonistic teleology based in an understanding of human nature. At first glance, the skepticism of Sextus Empiricus as described in the Outlines of Pyrrhonism seems to fit into this model insofar as he describes the end of the skeptic as ataraxia, a common account of the expression of human happiness. I argue that this is a misunderstanding of Sextus’s philosophy for several reasons. “The end of skepticism” cannot be eudaimonistic or teleological in the way that other ancient ethical theories are typically understood; moreover, ataraxia is not an end derived from a theory about human nature. For these reasons, the skeptical way of life is radically different than the ethical theories proposed by other schools. I argue that this difference is a result of the character of the skeptical enterprise which involves the implicit rejection of norms in both the epistemological and the ethical spheres

Skeptical science : the Pyrrhonian critique of technai in Against the Professors (M I-VI)

textThe central question of this dissertation is “What is the character of a skeptical expertise?” Sextus Empiricus, our primary source for Pyrrhonian skepticism, tells us that a skeptic has the ability to oppose thoughts and appearances in any number of ways in order to create an equally weighted dispute which results in epochē, the suspension of judgment (Outlines of Pyrrhonism [=PH] I 8). Scholars have debated the extent to which skeptics eschewed beliefs, but one thing is clear, the skeptic does not assent to the dogmatic claims of philosophy and science (PH I 13). This raises to group of related puzzles since Sextus also says that skeptics accept certain forms of expertise (technai) (PH I 24). If skeptics accept and practice certain technai, but also suspend judgment about all scientific or philosophical beliefs, what kind of science do they practice? I answer this question by interpreting Sextus' treatise Against the Professors (M I-VI), which offers his most thorough look at particular subjects of expertise. I argue for the following characteristics of skeptical technai: First, an adequate skeptical expertise is constituted by a collection of correlated observed phenomena (what he calls commemorative signs) established empirically through repeated observations, and always open to revision. The objects of these technai are limited to observable domains; that is, both the sign and the signified can in some sense be observed. All the same, commemorative signs allow the skeptic to predict future observable occurrences. Second, skeptical expertise is a non-axiomatic or, more generally, non-foundationalist science. Pyrrhonists did not ground the scientific domain in first principles in the way that many ancient philosophers of science do. Finally, the skeptical expertise is normative, but strictly in a relativistic sense. Scientific norms are tied to relative utility rather than truth. No expertise can be countenanced that offers theoretical rewards, just as no theoretical objects may be signified. Skeptical expertise is not some grand solution, but it achieves what is needed for practical purposes.Philosoph

Colliding Worlds: Modern Computational Methods for Scattering Amplitude Calculations and Responding to Crisis Situations

Precision theoretical predictions for high multiplicity scattering rely on the evaluation of increasingly complicated scattering amplitudes which come with an extremely high CPU cost. For state-of-the-art processes this can cause technical bottlenecks in the production of fully differential distributions. In this thesis we explore the possibility of using neural networks to approximate multi-jet scattering amplitudes and provide efficient inputs for Monte Carlo integration. We begin by focussing on QCD corrections to $e^+e^- \to \leq 5$ jets up to one-loop. We demonstrate reliable interpolation when a series of networks are trained on amplitudes that have been divided into sectors defined by their infrared singularity structure. Complete simulations for one-loop distributions show speed improvements of at least an order of magnitude over standard approaches. We extend our analysis to the case of loop-induced diphoton production through gluon fusion and develop a realistic simulation method that can be applied to hadron collider observables. Specifically, we present a detailed study for $2\to3$ and $2\to4$ scattering problems which are extremely relevant for future phenomenological studies and find excellent agreement with amplitudes generated using traditional methods. In order to provide a useable technology, we present an interface with the \sherpa~Monte Carlo event generator. The techniques underlying our machine learning methodology and Monte Carlo event generator simulations are widely applicable in other domains as well. In this thesis we will also discuss the use of machine learning to aid in rapid response to crises situations, and the parallels between multi-particle event generators and multi-agent simulations for modelling the spread of epidemics. In this latter case, we develop a new agent-based model with highly granular resolution and discuss its applications to modelling the spread of COVID-19 in England, and in refugee and internally displaced person settlements to aid data driven decision making

INTERREGIONAL COMPETITION IN THE U.S. SWINE-PORK INDUSTRY: AN ANALYSIS OF OKLAHOMA'S AND THE SOUTHERN STATES' EXPANSION POTENTIAL

Community/Rural/Urban Development,

In vitro studies of the synthesis of mitochondrial deoxyribonucleic acid

A DNA polymerase has been partially purified from the mitochondria of HeLa cells. Properties, including low levels of nuclease activity and a preference for native duplex DNA templates, were favorable for the study of in vitro DNA synthesis using circular duplex DNA templates. Initiation of DNA synthesis occurs predominately at single-strand scissions with covalent addition of nucleotides to the priming template strand. Centrifugation and electron microscopy have established that the template DNA strand ahead of the growing point is displaced rather than degraded. Hairpin structures are not formed in the course of DNA synthesis on duplex DNA templates. Studies with HeLa cell mitochondrial DNA template have indicated base composition-complement fidelity of the product of DNA synthesis as well as a preferential synthesis of DNA corresponding to the denser complement (in CsCl solution) of the template. This asymmetric synthesis of mitochondrial DNA appears to arise from a bias in the number of single-strand scissions sustained by the complementary strands. DNA synthesis in isolated HeLa cell mitochondria has also been investigated. Product DNA appears in closed and nicked circular mitochondrial DNA. Preferential synthesis of DNA corresponding to the less dense complement (in CsCI solution) was observed. The mode of action of the partially purified mitochondrial DNA polymerase and the asymmetric synthesis of mitochonarial DNA, observed in vitro and in situ, are discussed with regard to the results of recent studies of the replication of mitochondrial DNA in vivo. </p

Tellurium, selenium and cobalt enrichment in Neoproterozoic black shales, Gwna Group, UK : Deep marine trace element enrichment during the Second Great Oxygenation Event

We are grateful to John Still for his skilled technical support and the ACEMAC facility at the University of Aberdeen. Research funded by NERC grant NE/M010953/1 and NERC facility grant IP-1631-0516. AJB is funded by NERC support of the Isotope Community Support Facility SUERC. The authors thank Eva Stüeken, Ross Large and one anonymous reviewer for their constructive feedback on the original manuscript.Peer reviewedPublisher PD

Multi-AI Complex Systems in Humanitarian Response

AI is being increasingly used to aid response efforts to humanitarian emergencies at multiple levels of decision-making. Such AI systems are generally understood to be stand-alone tools for decision support, with ethical assessments, guidelines and frameworks applied to them through this lens. However, as the prevalence of AI increases in this domain, such systems will begin to encounter each other through information flow networks created by interacting decision-making entities, leading to multi-AI complex systems which are often ill understood. In this paper we describe how these multi-AI systems can arise, even in relatively simple real-world humanitarian response scenarios, and lead to potentially emergent and erratic erroneous behavior. We discuss how we can better work towards more trustworthy multi-AI systems by exploring some of the associated challenges and opportunities, and how we can design better mechanisms to understand and assess such systems. This paper is designed to be a first exposition on this topic in the field of humanitarian response, raising awareness, exploring the possible landscape of this domain, and providing a starting point for future work within the wider community.Comment: 8 pages, 1 figur

KINEMATIC AND KINETIC COMPARISON BETWEEN PRE-PROFESSIONAL DOMINICAN REPUBLIC AND AMERICAN BASEBALL PITCHERS

The purpose of this study was to compare elbow valgus torque and shoulder distraction force in pre-professional American and Dominican Republic (DR) pitchers. Kinematics that are known to influence elbow valgus torque and shoulder distraction force were also compared. Three dimensional biomechanical analyses were performed on Dominican Republic (n = 37) and American (n = 37) baseball pitchers. Potential difference between Dominican Republic and American pitchers were assessed through analysis of covariance with 95% confidence intervals. Age, hand dominance, and pitch velocity are known to influence elbow torque and shoulder force, therefore these confounding variables were controlled for within the analyses. Pre-professional Dominican Republic pitchers were found to throw fastballs with slower ball velocity but experienced increased elbow valgus torque compared to their American counterparts. Increased elbow valgus torque and inefficient pitching mechanics among Dominican Republic pitchers should be considered when developing training programs and pitching plans for professional pitchers from the Dominican Republic