2,815 research outputs found
The archaeological evidence of the Hwiccian area
The Hwicce, assessed at 7,000 hides (C.S.297), are probably one of the best documented representatives of the early Anglo-Saxon tribal groups which settled in England. They never had the political power wielded by the major kingdoms but were important enough to have their own bishop whose parochia preserved the tribe's territorial extent within the modern counties of Warwickshire, Worcestershire and Gloucestershire. I have used material from the pagan Anglo-Saxon burials in the West Midlands, together with saucer and applied brooches and small-long brooches from other parts of England, for the detailed analyses in this study. The classification of archaeological objects is frequently by uncorroborated typologies which are based upon imprecisely specified criteria. I have used cluster analysis methods in this examination and have produced four typologies which I have then used as checks on the validity of extant ones. My results, based upon the constant consideration of many specified attributes, are substantiated by several analyses. The illustrations, mapping of distributions and lists of key diagnostic features make my typologies simpler to use than earlier ones. From the brooch typologies it is possible to see trading and possible cultural patterns within England and this had been used to show that the pagan Anglo-Saxon peoples of the West Midlands had the closest affinities with Middle Anglia. A brief examination of place-names shows support for the links indicated by the archaeological evidence although these are not supported by the historical sources. Where the documentary sources are vital, however, is in the delimitation of the territory used in this study, the kingdom of the Hwicce, which has been shown in this work to have had distinctive material possessions
Social subordination alters estradiol-induced changes in cortico-limbic brain volumes in adult female rhesus monkeys
Women have a higher risk of developing stress-related disorders compared to men and the experience of a stressful life event is a potent risk-factor. The rodent literature suggests that chronic exposure to stressors as well as 17β-estradiol (E2) can result in alterations in neuronal structure in corticolimbic brain regions, however the translation of these data to humans is limited by the nature of the stressor experienced and issues of brain homology. To address these limitations, we used a well-validated rhesus monkey model of social subordination to examine effects of E2 treatment on subordinate (high stress) and dominant (low stress) female brain structure, including regional gray matter and white matter volumes using structural magnetic resonance imaging. Our results show that one month of E2 treatment in ovariectomized females, compared to control (no) treatment, decreased frontal cortex gray matter volume regardless of social status. In contrast, in the cingulate cortex, an area associated with stress-induced emotional processing, E2 decreased grey matter volume in subordinates but increased it in dominant females. Together these data suggest that physiologically relevant levels of E2 alter cortical gray matter volumes in females after only one month of treatment and interact with chronic social stress to modulate these effects on brain structure
Updated tests of scaling and universality for the spin-spin correlations in the 2D and 3D spin-S Ising models using high-temperature expansions
We have extended, from order 12 through order 25, the high-temperature series
expansions (in zero magnetic field) for the spin-spin correlations of the
spin-S Ising models on the square, simple-cubic and body-centered-cubic
lattices. On the basis of this large set of data, we confirm accurately the
validity of the scaling and universality hypotheses by resuming several tests
which involve the correlation function, its moments and the exponential or the
second-moment correlation-lengths.Comment: 21 pages, 8 figure
Chiral Symmetry in Light-front QCD
The definition of chiral transformations in light-front field theory is very
different from the conventional form in equal-time formalism. We study the
consistency of chiral transformations and chiral symmetry in light-front QCD
and derive a complete new light-front axial-vector current for QCD. The
breaking of chiral symmetry in light-front QCD is only associated with helicity
flip interaction between quarks and gluons. Remarkably, the new axial-vector
current does not contain the pion pole part so that the associate chiral charge
smoothly describes pion transitions for various hadronic processes.Comment: 15 pages, no figure, JHEP style, added reference and corrected typos
and some changed conten
Renormalization group and 1/N expansion for 3-dimensional Ginzburg-Landau-Wilson models
A renormalization-group scheme is developed for the 3-dimensional
O()-symmetric Ginzburg-Landau-Wilson model, which is consistent with the
use of a 1/N expansion as a systematic method of approximation. It is motivated
by an application to the critical properties of superconductors, reported in a
separate paper. Within this scheme, the infrared stable fixed point controlling
critical behaviour appears at , where is the inverse of
the quartic coupling constant, and an efficient renormalization procedure
consists in the minimal subtraction of ultraviolet divergences at . This
scheme is implemented at next-to-leading order, and the standard results for
critical exponents calculated by other means are recovered. An apparently novel
result of this non-perturbative method of approximation is that corrections to
scaling (or confluent singularities) do not, as in perturbative analyses,
appear as simple power series in the variable . At least in
three dimensions, the power series are modified by powers of .Comment: 20 pages; 5 figure
The Effect of Large Amplitude Fluctuations in the Ginzburg-Landau Phase Transition
The lattice Ginzburg-Landau model in d=3 and d=2 is simulated, for different
values of the coherence length in units of the lattice spacing , using
a Monte Carlo method. The energy, specific heat, vortex density , helicity
modulus and mean square amplitude are measured to map the phase
diagram on the plane . When amplitude fluctuations, controlled by the
parameter , become large () a proliferation of vortex
excitations occurs changing the phase transition from continuous to first
order.Comment: 4 pages, 5 postscript (eps) figure
Ultraviolet Fixed Points in Gauge and SUSY Field Theories in Extra Dimensions
We consider gauge field theories in following the Wilson RG approach
and show that they possess the ultraviolet fixed points where the gauge
coupling is dimensionless in any space-time dimension. At the fixed point the
anomalous dimensions of the field and vertex operators are known exactly. These
fixed points are nonperturbative and correspond to conformal invariant
theories. The same phenomenon also happens in supersymmetric theories with the
Yukawa type interactions.Comment: LaTeX, 10pp. v2: Comments and references adde
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