321 research outputs found
Citation Methodologies in Eusebiusâ Historia Ecclesiastica and Other Ancient Historiography
This dissertation examines ancient historiographic citation methodologies in light of Mikhail Bakhtinâs dichotomy between polyphony and monologization. In particular, this dissertation argues that Eusebius of Caesareaâs Historia ecclesiastica (HE) abandons the monologic citation methodology typical of previous Greek and Hellenistic historiography and introduces a polyphonic citation methodology that influences subsequent late-ancient Christian historiography to varying degrees. Whereas Pre-Eusebian Greek and Hellenistic historiographers typically use citations to support the single authorial consciousness of the historiographer, Eusebius uses citations to counterbalance his own shortcomings as a witness to past events. Eusebius allows his citations to retain their own voice, even when they conflict with his. The result is a narrative that transcends the point of view of any single individual and makes multiple witnesses, including the narrator, available to the reader.
Post-Eusebian late-ancient Christian historiographers exhibit the influence of Eusebiusâ innovation, but they are not as intentional as Eusebius in their use of citation methodologies. Many subsequent Christian historiographers use both monologic and polyphonic citation methodologies. Their tendency to follow Eusebiusâ practice of citing numerous lengthy citations sometimes emphasizes points of view that oppose the authorâs point of view. When an opposing viewpoint surfaces in enough citations, a polyphonic citation methodology emerges. The reader holds the two different narrative strands in tension as the author continues to give voice to opposing viewpoints.
After illustrating the citation methodologies with passages from numerous Greek, Hellenistic, and late ancient Christian historiographers, this dissertation concludes with a short computational analysis that uses natural language processing to reveal some broad trends that highlight the previous findings and suggest a possibility for future research
Exact finite-size scaling with corrections in the two-dimensional Ising model with special boundary conditions
The two-dimensional Ising model with Brascamp-Kunz boundary conditions has a
partition function more amenable to analysis than its counterpart on a torus.
This fact is exploited to exactly determine the full finite-size scaling
behaviour of the Fisher zeroes of the model. Moreover, exact results are also
determined for the scaling of the specific heat at criticality, for the
specific-heat peak and for the pseudocritical points. All corrections to
scaling are found to be analytic and the shift exponent does not
coincide with the inverse of the correlation length exponent .Comment: 3 pages, LaTeX, No figures, Lattice2001(spin
Briefing Note : Workshop on Developing a Model Anti-SLAPP Law for Scotland
Workshop reportPublisher PD
Transport and Spectroscopic Studies of the Effects of Fullerene Structure on the Efficiency and Lifetime of Polythiophene-based Solar Cells
Time-dependent measurements of both power conversion efficiency and
ultraviolet-visible absorption spectroscopy have been observed for solar cell
blends containing the polymer poly(3-hexylthiophene-2,5-diyl) (P3HT) with two
different functionalized C60 electron acceptor molecules: commercially
available [6,6]-phenyl C61 butyric acid methyl ester (PCBM) or [6,6]-phenyl C61
butyric acid octadecyl ester (PCBOD) produced in this laboratory. Efficiency
was found to decay with an exponential time dependence, while spectroscopic
features show saturating exponential behavior. Time constants extracted from
both types of measurements showed reasonable agreement for samples produced
from the same blend. In comparison to the PCBM samples, the stability of the
PCBOD blends was significantly enhanced, while both absorption and power
conversion efficiency were decreased.Comment: manuscript submitted to Solar Energy Materials and Solar Cell
Examining the Effects of Formal Education Level on the Montreal Cognitive Assessment
Background: Brief, global assessments such as the Montreal Cognitive Assessment (MoCA) are widely used in primary care for assessing cognition in older adults. Like other neuropsychological instruments, lower formal education can influence MoCA interpretation.
Methods: Data from 2 large studies of cognitive aging were usedâAlzheimerâs Disease Neuroimaging Initiative (ADNI) and National Alzheimerâs Coordinating Center (NACC). Both use comprehensive examinations to determine cognitive status and have brain amyloid status for many participants. Mixed models were used to account for random variation due to data source.
Results: Cognitively intact participants with lower education (â€12 years) were more likely than those with higher education (\u3e12 years) to be classified as potentially impaired using the MoCA cutoff of \u3c26 (P \u3c .01). Backwards selection revealed 4 MoCA items significantly associated with education (cube copy, serial subtraction, phonemic fluency, abstraction). Subtracting these items scores yielded an alternative MoCA score with a maximum of 24 and a cutoff of â€19 for classifying participants with mild cognitive impairment. Using the alternative MoCA score and cutoff, among cognitively intact participants, both education groups were similarly likely to be classified as potentially impaired (P \u3e .67).
Conclusions: The alternative MoCA score neutralized the effects of formal education. Although further research is needed, this alternative score offers a simple procedure for interpreting MoCAs administered to older adults with â€12 years education. These educational effects also highlight that the MoCA is part of the assessment processânot a singular diagnostic testâand a comprehensive workup is necessary to accurately diagnose cognitive impairments
The Calculation of Critical Amplitudes in SU(2) Lattice Gauge Theory
We calculate the critical amplitudes of the Polyakov loop and its
susceptibility at the deconfinement transition of (3+1) dimensional SU(2) gauge
theory. To this end we study the corrections due to irrelevant exponents in the
scaling functions. As a guiding line for determining the critical amplitudes we
use envelope equations which we derive from the finite size scaling formulae of
the observables. We have produced new high precision data on N^3 x 4 lattices
for N=12,18,26 and 36. With these data we find different corrections to the
asymptotic scaling behaviour above and below the transition. Our result for the
universal ratio of the susceptibility amplitudes is C_+/C_-=4.72(11) and thus
in excellent agreement with a recent measurement for the 3d Ising model.Comment: 27 pages, 11 figures, Latex2
Critical Exponent for the Density of Percolating Flux
This paper is a study of some of the critical properties of a simple model
for flux. The model is motivated by gauge theory and is equivalent to the Ising
model in three dimensions. The phase with condensed flux is studied. This is
the ordered phase of the Ising model and the high temperature, deconfined phase
of the gauge theory. The flux picture will be used in this phase. Near the
transition, the density is low enough so that flux variables remain useful.
There is a finite density of finite flux clusters on both sides of the phase
transition. In the deconfined phase, there is also an infinite, percolating
network of flux with a density that vanishes as . On
both sides of the critical point, the nonanalyticity in the total flux density
is characterized by the exponent . The main result of this paper is
a calculation of the critical exponent for the percolating network. The
exponent for the density of the percolating cluster is . The specific heat exponent and the crossover exponent
can be computed in the -expansion. Since , the variation in the separate densities is much more rapid than
that of the total. Flux is moving from the infinite cluster to the finite
clusters much more rapidly than the total density is decreasing.Comment: 20 pages, no figures, Latex/Revtex 3, UCD-93-2
Critical behavior and scaling in trapped systems
We study the scaling properties of critical particle systems confined by a
potential. Using renormalization-group arguments, we show that their critical
behavior can be cast in the form of a trap-size scaling, resembling finite-size
scaling theory, with a nontrivial trap critical exponent theta, which describes
how the correlation length scales with the trap size l, i.e., at the critical point. theta depends on the universality class of the
transition, the power law of the confining potential, and on the way it is
coupled to the critical modes. We present numerical results for two-dimensional
lattice gas (Ising) models with various types of harmonic traps, which support
the trap-size scaling scenario.Comment: 4 pages, 6 figs, minor correction
Critical behavior of systems with long-range interaction in restricted geometry
The present review is devoted to the problems of finite-size scaling due to
the presence of long-range interaction decaying at large distance as
, . The attention is focused mainly on the
renormalization group results in the framework of -
theory for systems with fully finite (block) geometry under periodic boundary
conditions. Some bulk critical properties and Monte Carlo results also are
reviewed. The role of the cutoff effects as well their relation with those
originating from the long-range interaction is also discussed. Special
attention is paid to the description of the adequate mathematical technique
that allows to treat the long-range and short-range interactions on equal
ground. The review closes with short discussion of some open problems.Comment: New figures are added. Now 17 pages including 4 figures. Accepted for
publication in Modren Physics Letter
Generalized-ensemble simulations and cluster algorithms
The importance-sampling Monte Carlo algorithm appears to be the universally
optimal solution to the problem of sampling the state space of statistical
mechanical systems according to the relative importance of configurations for
the partition function or thermal averages of interest. While this is true in
terms of its simplicity and universal applicability, the resulting approach
suffers from the presence of temporal correlations of successive samples
naturally implied by the Markov chain underlying the importance-sampling
simulation. In many situations, these autocorrelations are moderate and can be
easily accounted for by an appropriately adapted analysis of simulation data.
They turn out to be a major hurdle, however, in the vicinity of phase
transitions or for systems with complex free-energy landscapes. The critical
slowing down close to continuous transitions is most efficiently reduced by the
application of cluster algorithms, where they are available. For first-order
transitions and disordered systems, on the other hand, macroscopic energy
barriers need to be overcome to prevent dynamic ergodicity breaking. In this
situation, generalized-ensemble techniques such as the multicanonical
simulation method can effect impressive speedups, allowing to sample the full
free-energy landscape. The Potts model features continuous as well as
first-order phase transitions and is thus a prototypic example for studying
phase transitions and new algorithmic approaches. I discuss the possibilities
of bringing together cluster and generalized-ensemble methods to combine the
benefits of both techniques. The resulting algorithm allows for the efficient
estimation of the random-cluster partition function encoding the information of
all Potts models, even with a non-integer number of states, for all
temperatures in a single simulation run per system size.Comment: 15 pages, 6 figures, proceedings of the 2009 Workshop of the Center
of Simulational Physics, Athens, G
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