48 research outputs found
Solutions of D_\alpha - 0 from Homogeneous Invariant Functions
We prove that the existence of a homogeneous invariant of degree n for a
representation of a semi-simple Lie group guarantees the existence of
non-trivial solutions of D_{\alpha} = 0: these correspond to the maximum value
of the square of the invariant divided by the norm of the representation to the
n^{th} power.Comment: 4 pages, late
Gravitating BPS Dyons witout a Dilaton
We describe curved-space BPS dyon solutions, the ADM mass of which saturates
the gravitational version of the Bogomol'nyi bound. This generalizes
self-gravitating BPS monopole solutions of Gibbons et al. when there is no
dilaton.Comment: 10 page
Characterization of a Bartonella Bacilliformis Human Factor H-Binding Protein
Bartonella bacilliformis is a human bacterial pathogen and the etiological agent of Carrion’s Disease. B. bacilliformis is serum resistant, allowing it to survive in the human bloodstream and persist and replicate in erythrocytes. Human Factor H is a circulating protein in human blood that is part of the complement cascade of innate immune defense. Factor H binds to self-cells and prevents auto-immunity by complement fixation. A Far-Western blot followed by mass spectrometry analysis suggests that B. bacilliformis can bind to human Factor H protein. Here, we describe the protein BB1133, an outer membrane auto-transporter, and the Factor H—binding protein identified by mass spectrometry. By splitting the protein into two distinct domains, each domain is able to be expressed in E. coli via the Gateway cloning system and the pET-Dest42 vector. IPTG induction of the domains, followed by a Far-Western blot utilizing human Factor H as a probe, will indicate which domain of BB1133 is human Factor H—binding
Supersymmetric Flat Directions and Analytic Gauge Invariants
We review some aspects of the correspondence between analytic gauge
invariants and supersymmetric flat directions for vanishing D-terms and propose
a criterion to include the F-term constraints.Comment: 8 pages, Late
Softly Broken N=1 Supersymmetric QCD
We study softly broken N=1 supersymmetric QCD with the gauge group
and flavours of quarks for . We investigate the phase
structure of its dual theory adding generic soft supersymmetry breking terms,
i.e. soft scalar masses, trilinear coupling terms of scalar fields and gaugino
masses. It is found that the trilinear coupling terms play an improtant role in
determining the potential minima. Also we compare softly broken original and
dual theories in the broken phase.Comment: 16 pages, latex, 2 figure
Remarks on the Racetrack Scheme
There are only a small number of ideas for stabilizing the moduli of string
theory. One of the most appealing of these is the racetrack mechanism, in which
a delicate interplay between two strongly interacting gauge groups fixes the
value of the coupling constant. In this note, we explore this scenario. We find
that quite generally, some number of discrete tunings are required in order
that the mechanism yield a small gauge coupling. Even then, there is no sense
in which a weak coupling approximation is valid. On the other hand, certain
holomorphic quantities can be computed, so such a scheme is in principle
predictive. Searching for models which realize this mechanism is thus of great
interest. We also remark on cosmology in these schemes.Comment: 20 pp, latex, discussion of calculability modifie
Probe measurements of plasma potential nonuniformity due to edge asymmetry in large-area radio-frequency reactors: the telegraph effect
In large-area radio-frequency (rf) capacitive reactors, the redistribution of rf current to maintain current continuity near asymmetric sidewalls causes a perturbation in rf plasma potential to propagate along the resistive plasma between capacitive sheaths. The damping length of the perturbation can be determined by a telegraph equation. Experiments are described using a surface array of unbiased electrostatic probes in the ground electrode to verify the theoretical model of the telegraph effect in Howling [J. Appl. Phys. 96, 5429 (2004)]. The measured spatial dependence of the plasma potential rf amplitude and circulating nonambipolar current agree well with two-dimensional numerical solutions of the telegraph equation. The rf plasma potential can be made uniform by using symmetric reactor sidewalls
Twisted Sectors and Chern-Simons Terms in M-Theory Orbifolds
It is shown that the twisted sector spectrum, as well as the associated
Chern-Simons interactions, can be determined on M-theory orbifold fixed planes
that do not admit gravitational anomalies. This is demonstrated for the
seven-planes arising within the context of an explicit orbifold, although the results are completely general. Local
anomaly cancellation in this context is shown to require fractional anomaly
data that can only arise from a twisted sector on the seven-planes, thus
determining the twisted spectrum up to a small ambiguity. These results open
the door to the construction of arbitrary M-theory orbifolds, including those
containing fixed four-planes which are of phenomenological interest.Comment: 21 pages, LaTe