57 research outputs found
Two-dimensional Copolymers and Multifractality: Comparing Perturbative Expansions, MC Simulations, and Exact Results
We analyze the scaling laws for a set of two different species of long
flexible polymer chains joined together at one of their extremities (copolymer
stars) in space dimension D=2. We use a formerly constructed field-theoretic
description and compare our perturbative results for the scaling exponents with
recent conjectures for exact conformal scaling dimensions derived by a
conformal invariance technique in the context of D=2 quantum gravity. A simple
MC simulation brings about reasonable agreement with both approaches. We
analyse the remarkable multifractal properties of the spectrum of scaling
exponents.Comment: 5 page
Scaling in DNA unzipping models: denaturated loops and end-segments as branches of a block copolymer network
For a model of DNA denaturation, exponents describing the distributions of
denaturated loops and unzipped end-segments are determined by exact enumeration
and by Monte Carlo simulations in two and three dimensions. The loop
distributions are consistent with first order thermal denaturation in both
cases. Results for end-segments show a coexistence of two distinct power laws
in the relative distributions, which is not foreseen by a recent approach in
which DNA is treated as a homogeneous network of linear polymer segments. This
unexpected feature, and the discrepancies with such an approach, are explained
in terms of a refined scaling picture in which a precise distinction is made
between network branches representing single stranded and effective double
stranded segments.Comment: 8 pages, 8 figure
Scaling behaviour of lattice animals at the upper critical dimension
We perform numerical simulations of the lattice-animal problem at the upper
critical dimension d=8 on hypercubic lattices in order to investigate
logarithmic corrections to scaling there. Our stochastic sampling method is
based on the pruned-enriched Rosenbluth method (PERM), appropriate to linear
polymers, and yields high statistics with animals comprised of up to 8000
sites. We estimate both the partition sums (number of different animals) and
the radii of gyration. We re-verify the Parisi-Sourlas prediction for the
leading exponents and compare the logarithmic-correction exponents to two
partially differing sets of predictions from the literature. Finally, we
propose, and test, a new Parisi-Sourlas-type scaling relation appropriate for
the logarithmic-correction exponents.Comment: 10 pages, 5 figure
Noisy random resistor networks: renormalized field theory for the multifractal moments of the current distribution
We study the multifractal moments of the current distribution in randomly
diluted resistor networks near the percolation treshold. When an external
current is applied between to terminals and of the network, the
th multifractal moment scales as , where is the correlation length exponent of
the isotropic percolation universality class. By applying our concept of master
operators [Europhys. Lett. {\bf 51}, 539 (2000)] we calculate the family of
multifractal exponents for to two-loop order. We find
that our result is in good agreement with numerical data for three dimensions.Comment: 30 pages, 6 figure
Sex Segregation and Salary Structure in Academia
This article reports a study of aggregate unit salary levels, within a major research university. We analyze these salary levels, as they are influenced by unit sex composition, and modified by unit attainment levels—where unit refers to the departments, colleges and schools, and other academic divisions of the university. We investigate three central issues of sex and salary, previously overlooked in salary studies of academic employees: Do high proportions of women depress men's unit salary levels ("competition" hypothesis)? Are women's salary levels higher in male-dominated, and lower in female-dominated, units ("concentration" hypothesis)? Are men salary-compensated for working with women ("compensation" hypothesis)? The findings support none of these hypotheses. Rather, the relationship between unit sex composition and salary rests upon the connection between units' composition and attainment levels.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69126/2/10.1177_073088848100800103.pd
"Kill the Damn Masters!" : Narratives of Religious War and Social Conflict in Kvistbro parish 1843
This thesis examines narratives of the events called ”The War of Religion in Kvistbro”, a violent turmoil that erupted in Närke, Sweden 1843. The events involved persons connected to the Shouter Movement, a pietist inspired revivalist movement, and governmental officials who were ordered to arrest a preacher.A narrative analysis based on a model inspired by Labov and Chatman, is used for examining contemporary local newspaper Nerikes Allehanda's and the revivalist historian E. J.Ekman's narrations of the events. The theoretical framework of this thesis is founded on Charles Tilly's theory of collective violence, and James C Scott's theories of hidden transcripts and weapons of the weak.The results of the analysis indicates that there are three main understandings of the events within the empiric material: a religious framing, a medical framing, and a socio-political reading. The socio-political reading of the narratives implies that the concepts medicine as control, social antagonism, and gender-coded aspects of conflict, emerge from the material
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