195 research outputs found
The aetiology of the proliferative enteropathies.
SIGLEAvailable from British Library Document Supply Centre- DSC:DX77038 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
(0,2) Deformations of Linear Sigma Models
We study (0,2) deformations of a (2,2) supersymmetric gauged linear sigma
model for a Calabi-Yau hypersurface in a Fano toric variety. In the non-linear
sigma model these correspond to some of the holomorphic deformations of the
tangent bundle on the hypersurface. Combinatorial formulas are given for the
number of these deformations, and we show that these numbers are exchanged by
mirror symmetry in a subclass of the models.Comment: 35 pages; uses xy-fig; typos fixed, acknowledgments adde
A longitudinal study of porcine proliferative enteropathy in a commercial pig farm in Yucatan Mexico
Low levels of methicillin resistant Staphylococcus aureus in pigs in Malaysia.
The aim of this study was to establish the levels of methicillin resistant Staphylococcus aureus (MRSA) in pigs in Malaysia. Nasal mucosa swabs were obtained from 400 pigs (4-5 weeks old) in 5 farms in Selangor and Perak states [date not given]. Bacteria were cultured from 123 pigs. The numbers of putative mecA + MRSA isolates per farm were 0, 0, 0, 1 and 3, respectively. Farms D and E in Selangor had multiresistant S. aureus, including MRSA compared with the other farms
Association between average daily gain, faecal dry matter content and concentration of Lawsonia intracellularis in faeces
<p>Abstract</p> <p>Background</p> <p>The objective of this study was to investigate the association between average daily gain and the number of <it>Lawsonia intracellularis</it> bacteria in faeces of growing pigs with different levels of diarrhoea.</p> <p>Methods</p> <p>A longitudinal field study (<it>n</it> = 150 pigs) was performed in a Danish herd from day 29 to 47 post weaning. Every third day all pigs were weighed, subjected to a clinical examination and faecal samples were obtained. Faecal samples were subjected to dry matter determination and absolute quantification by PCR for <it>L. intracellularis</it> and porcine circovirus type 2 (PCV2). Association between average daily gain, faecal dry matter content, numbers of <it>L. intracellularis</it> bacteria and PCV2 genome copies in faeces was investigated in a multilevel mixed-effects linear model.</p> <p>Results</p> <p>Increasing numbers of <it>L. intracellularis</it> log<sub>10</sub> bacteria/g faeces were significantly associated with decreasing average daily gain (<it>P</it> < 0.001). The association was decreasing with increasing faecal dry matter content (<it>P</it> < 0.01). The number of PCV2 log<sub>10</sub> copies/g faeces was not significantly associated with average daily gain of the pigs (<it>P</it> > 0.5).</p> <p>Conclusion</p> <p>The results suggest a potential application of a PCR quantifying <it>L. intracellularis</it> in growing pigs. Faecal dry matter content must be taken into consideration in interpretation of such test results.</p
New Examples of Flux Vacua
Type IIB toroidal orientifolds are among the earliest examples of flux vacua.
By applying T-duality, we construct the first examples of massive IIA flux
vacua with Minkowski space-times, along with new examples of type IIA flux
vacua. The backgrounds are surprisingly simple with no four-form flux at all.
They serve as illustrations of the ingredients needed to build type IIA and
massive IIA solutions with scale separation. To check that these backgrounds
are actually solutions, we formulate the complete set of type II supergravity
equations of motion in a very useful form that treats the R-R fields
democratically.Comment: 38 pages, LaTeX; references updated; additional minor comments added;
published versio
IIA Perspective On Cascading Gauge Theory
We study the N=1 supersymmetric cascading gauge theory found in type IIB
string theory on p regular and M fractional D3-branes at the tip of the
conifold, using the T-dual type IIA description. We reproduce the
supersymmetric vacuum structure of this theory, and show that the IIA analog of
the non-supersymmetric state found by Kachru, Pearson and Verlinde in the IIB
description is metastable in string theory, but the barrier for tunneling to
the supersymmetric vacuum goes to infinity in the field theory limit. We also
comment on the N=2 supersymmetric gauge theory corresponding to regular and
fractional D3-branes on a near-singular K3, and clarify the origin of the
cascade in this theory.Comment: 43 pages, 18 figures, harvma
Novel Branches of (0,2) Theories
We show that recently proposed linear sigma models with torsion can be
obtained from unconventional branches of conventional gauge theories. This
observation puts models with log interactions on firm footing. If non-anomalous
multiplets are integrated out, the resulting low-energy theory involves log
interactions of neutral fields. For these cases, we find a sigma model geometry
which is both non-toric and includes brane sources. These are heterotic sigma
models with branes. Surprisingly, there are massive models with compact complex
non-Kahler target spaces, which include brane/anti-brane sources. The simplest
conformal models describe wrapped heterotic NS5-branes. We present examples of
both types.Comment: 36 pages, LaTeX, 2 figures; typo in Appendix fixed; references added
and additional minor change
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