63 research outputs found
The Logarithmic Conformal Field Theories
We study the correlation functions of logarithmic conformal field theories.
First, assuming conformal invariance, we explicitly calculate two-- and three--
point functions. This calculation is done for the general case of more than one
logarithmic field in a block, and more than one set of logarithmic fields. Then
we show that one can regard the logarithmic field as a formal derivative of the
ordinary field with respect to its conformal weight. This enables one to
calculate any -- point function containing the logarithmic field in terms of
ordinary --point functions. At last, we calculate the operator product
expansion (OPE) coefficients of a logarithmic conformal field theory, and show
that these can be obtained from the corresponding coefficients of ordinary
conformal theory by a simple derivation.Comment: 17 pages ,latex , some minor changes, to appear in Nucl. Phys.
Global Conformal Invariance in D-dimensions and Logarithmic Correlation Functions
We define transformation of multiplets of fields (Jordan cells) under the
D-dimensional conformal group, and calculate two and three point functions of
fields, which show logarithmic behaviour. We also show how by a formal
differentiation procedure, one can obtain n-point function of logarithmic field
theory from those of ordinary conformal field theory.Comment: 9 pages, LaTeX, some misprints are corrected, to be published in
Phys. Lett.
Logarithmic N=1 superconformal field theories
We study the logarithmic superconformal field theories. Explicitly, the
two-point functions of N=1 logarithmic superconformal field theories (LSCFT)
when the Jordan blocks are two (or more) dimensional, and when there are one
(or more) Jordan block(s) have been obtained. Using the well known three-point
fuctions of N=1 superconformal field theory (SCFT), three-point functions of
N=1 LSCFT are obtained. The general form of N=1 SCFT's four-point functions is
also obtained, from which one can easily calculate four-point functions in N=1
LSCFT.Comment: 10 pages, LaTeX file, minor revisions made, to appear in Phys. Lett.
Logarithmic Correlation Functions in Two Dimensional Turbulence
We consider the correlation functions of two-dimensional turbulence in the
presence and absence of a three-dimensional perturbation, by means of conformal
field theory. In the persence of three dimensional perturbation, we show that
in the strong coupling limit of a small scale random force, there is some
logarithmic factor in the correlation functions of velocity stream functions.
We show that the logarithmic conformal field theory describes the 2D-
turbulence both in the absence and the presence of the perturbation. We obtain
the following energy spectrum for perturbed 2D
- turbulence and for unperturbed turbulence. Recent
numerical simulation and experimental results confirm our prediction.Comment: 14 pages ,latex , no figure
Quenched Averaged Correlation Functions of the Random Magnets
It is shown that the ratios of the quenched averaged three and four-point
correlation functions of the local energy density operator to the connected
ones in the random-bond Ising model approach asymptotically to some
functions. We derive the explicit expressions of these universal functions.
Moreover it is shown that the individual logarithmic operators have not any
contribution to the connected correlation functions of the disordered Ising
model.Comment: 4 pages, twocolumn, to appear in Nucl. Physics
A Logarithmic Conformal Field Theory Solution For Two Dimensional Magnetohydrodynamics In Presence of The Alf'ven Effect
When Alf`ven effect is peresent in magnetohydrodynamics one is naturally lead
to consider conformal field theories, which have logarithmic terms in their
correlation functions. We discuss the implications of such logarithmic terms
and find a unique conformal field theory with centeral charge
, within the border of the minimal series, which satisfies
all the constraints. The energy espectrum is found to be \newline .Comment: Latex, 9 page
Variation in Fatty Acid Composition of Four Turkish Registered Poppy (Papaver somniferum L.) Seeds in two Locations (Ankara and Boldavin) of Turkey
Opium poppy (Papaver somniferum L.) has two major products: alkaloids in the capsules and the seeds. Poppy seed oil is a rich source of polyunsaturated fatty acids. It is known that polyunsaturated fatty acids present not only basic nutriments for human body, but protects against cardiovascular diseases, heart attacks and many inflammatory diseases. The aim of this study was to determine oil content and fatty acids composition in four Turkish registered poppy cultivars grown in experimental fields of the the Agronomy Department, of Ankara University and Bolvadin Factory of Alcaloids at the Afyon province, Turkey. All seeds were sown in 15 October 2009 and harvested in 20 July 2010. The oil was extracted and analysed with hexane by foss soxtec 2055 apparatus and fatty acids were analyzed by gas chromatography. Seed oil and fatty acids percentage of four different cultivars in two locations were determined. Oil contents of seed varieties ranged 40.20% - 47.95%. The major fatty acid in seed oils was linoleic acid (68.16 - 74.15%) whereas oleic and palmitic acid contents of seed oils ranged 14.22 - 16.47% and 7.96 - 12.87% respectively. In terms of oil content and unsaturated fatty acids concentration Bolvadin location is better compared to Ankara location
Boundary states in boundary logarithmic CFT
There exist logarithmic CFTs(LCFTs) such as the models. It is also
well known that it generally contains Jordan cell structure. In this paper, we
obtain the boundary Ishibashi state for a rank-2 Jordan cell structure and,
with these states in rational LCFT, we derive boundary states in the
closed string picture, which correspond to boundary conditions in the open
string picture. We also discuss the Verlinde formula for LCFT and possible
applications to string theory.Comment: LaTeX, 21 pages; a reference adde
A Local Logarithmic Conformal Field Theory
The local logarithmic conformal field theory corresponding to the triplet
algebra at c=-2 is constructed. The constraints of locality and crossing
symmetry are explored in detail, and a consistent set of amplitudes is found.
The spectrum of the corresponding theory is determined, and it is found to be
modular invariant. This provides the first construction of a non-chiral
rational logarithmic conformal field theory, establishing that such models can
indeed define bona fide conformal field theories.Comment: 29 pages, LaTeX, minor changes, reference adde
Treatment outcomes and risk factors of death in childhood tuberculous meningitis in Kandahar, Afghanistan: a prospective observational cohort study
Background: Tuberculous meningitis (TBM) is the most severe form of TB. We prospectively documented the treatment outcomes and the risk factors for death in children with TBM from Kandahar, Afghanistan.
Methods: This prospective observational cohort study was conducted from February 2017 to January 2020 in hospitalised TBM children. All the patients were prospectively followed up for 12 mo. Data were analysed by using descriptive statistics, χ2 and multivariate logistic regression.
Results: A total of 818 TBM hospitalised patients with median age 4.8 (0.8–14.5) y were recruited. Females accounted for 60.9% (498/818). Upon admission 53.9% (n=441) and 15.2% (n=124) had TBM stages II and III, respectively, and 23.2% (n=190) had focal neurological signs. The case fatality rate was 20.2% (160/794) and 30.6% (243/794) survived with neurological sequelae. Independent risk factors for death were being unvaccinated for BCG (adjusted OR [AOR] 3.8, 95% CI 1.8 to 8.1), not receiving dexamethasone (AOR 2.5, 95% CI 1.5 to 4.2), being male (AOR 2.3, 95% CI 1.5 to 3.6), history of recent weight loss (AOR 2.2, 95% CI 1.3 to 3.9) and having stage III TBM (AOR 2.0, 95% CI 1.2 to 3.3).
Conclusions: TBM continues to cause high morbidity and mortality in Afghan children. Strategies to reduce mortality should emphasise early diagnosis and treatment, routine use of dexamethasone and increased BCG vaccination
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