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Discovery of molecular subtypes in leiomyosarcoma through integrative molecular profiling.
Leiomyosarcoma (LMS) is a soft tissue tumor with a significant degree of morphologic and molecular heterogeneity. We used integrative molecular profiling to discover and characterize molecular subtypes of LMS. Gene expression profiling was performed on 51 LMS samples. Unsupervised clustering showed three reproducible LMS clusters. Array comparative genomic hybridization (aCGH) was performed on 20 LMS samples and showed that the molecular subtypes defined by gene expression showed distinct genomic changes. Tumors from the muscle-enriched cluster showed significantly increased copy number changes (P=0.04). A majority of the muscle-enriched cases showed loss at 16q24, which contains Fanconi anemia, complementation group A, known to have an important role in DNA repair, and loss at 1p36, which contains PRDM16, of which loss promotes muscle differentiation. Immunohistochemistry (IHC) was performed on LMS tissue microarrays (n=377) for five markers with high levels of messenger RNA in the muscle-enriched cluster (ACTG2, CASQ2, SLMAP, CFL2 and MYLK) and showed significantly correlated expression of the five proteins (all pairwise P<0.005). Expression of the five markers was associated with improved disease-specific survival in a multivariate Cox regression analysis (P<0.04). In this analysis that combined gene expression profiling, aCGH and IHC, we characterized distinct molecular LMS subtypes, provided insight into their pathogenesis, and identified prognostic biomarkers
Two-loop effective potential for a general renormalizable theory and softly broken supersymmetry
I compute the two-loop effective potential in the Landau gauge for a general
renormalizable field theory in four dimensions. Results are presented for the
\bar{MS} renormalization scheme based on dimensional regularization, and for
the \bar{DR} and \bar{DR}' schemes based on regularization by dimensional
reduction. The last of these is appropriate for models with softly broken
supersymmetry, such as the Minimal Supersymmetric Standard Model. I find the
parameter redefinition which relates the \bar{DR} and \bar{DR}' schemes at
two-loop order. I also discuss the renormalization group invariance of the
two-loop effective potential, and compute the anomalous dimensions for scalars
and the beta function for the vacuum energy at two-loop order in softly broken
supersymmetry. Several illustrative examples and consistency checks are
included.Comment: 38 pages. Typos in equations (3.5), (3.11), and (6.3) are fixed.
Explicit claim of renormalization group invariance in the general case of
softly-broken supersymmetry is added. Additional discussion of cases of
multiple simple or U(1) groups. Equations in Appendix B rewritten in a more
useful for
Self-consistently Improved Finite Temperature Effective Potential for Gauge Theories
The finite temperature effective potential of the Abelian Higgs Model is
studied using the self-consistent composite operator method, which sums up the
contributions of daisy and superdaisy diagrams. The effect of the momentum
dependence of the effective masses is estimated by using a Rayleigh-Ritz
variational approximation.Comment: 29 pages, 7 figures not included, Plain Tex, BUHEP-93-12, to appear
in Physical Review D49. (additional comments on renormalization and a more
quantitative comparison with previous results have been included, one more
figure, two new references, two references updated
Probing for Invisible Higgs Decays with Global Fits
We demonstrate by performing a global fit on Higgs signal strength data that
large invisible branching ratios Br_{inv} for a Standard Model (SM) Higgs
particle are currently consistent with the experimental hints of a scalar
resonance at the mass scale m_h ~ 124 GeV. For this mass scale, we find
Br_{inv} < 0.64 (95 % CL) from a global fit to individual channel signal
strengths supplied by ATLAS, CMS and the Tevatron collaborations. Novel tests
that can be used to improve the prospects of experimentally discovering the
existence of a Br_{inv} with future data are proposed. These tests are based on
the combination of all visible channel Higgs signal strengths, and allow us to
examine the required reduction in experimental and theoretical errors in this
data that would allow a more significantly bounded invisible branching ratio to
be experimentally supported. We examine in some detail how our conclusions and
method are affected when a scalar resonance at this mass scale has couplings
deviating from the SM ones.Comment: 32pp, 15 figures v2: JHEP version, ref added & comment added after
Eq.
Wavepacket Dynamics in Yang-Mills Theory
We discuss the results of numerical simulations of colliding wavepackets in
Yang--Mills theory. We investigate their behavior as a function of
amplitude and momentum distribution. We find regions in our parameter space in
which initial wave packets scatter into final configurations with dramatically
different momentum distributions. These results constitute new classical
trajectories with multiparticle boundary conditions. We explain their relevance
for the calculation of scattering amplitudes in the semiclassical
approximation. Finally, we give directions for future work.Comment: 11 pgs. text, 11 optional figs using PiCTeX and epsf, new version
contains improved discussion of scaling properties of results and one
additional figure
Robust LHC Higgs Search in Weak Boson Fusion
We demonstrate that an LHC Higgs search in weak boson fusion production with
subsequent decay to weak boson pairs is robust against extensions of the
Standard Model or MSSM involving a large number of Higgs doublets. We also show
that the transverse mass distribution provides unambiguous discrimination of a
continuum Higgs signal from the Standard Model.Comment: 12p, 2 figs., additional comments on backgrounds, version to appear
in PR
Energy Budget of Cosmological First-order Phase Transitions
The study of the hydrodynamics of bubble growth in first-order phase
transitions is very relevant for electroweak baryogenesis, as the baryon
asymmetry depends sensitively on the bubble wall velocity, and also for
predicting the size of the gravity wave signal resulting from bubble
collisions, which depends on both the bubble wall velocity and the plasma fluid
velocity. We perform such study in different bubble expansion regimes, namely
deflagrations, detonations, hybrids (steady states) and runaway solutions
(accelerating wall), without relying on a specific particle physics model. We
compute the efficiency of the transfer of vacuum energy to the bubble wall and
the plasma in all regimes. We clarify the condition determining the runaway
regime and stress that in most models of strong first-order phase transitions
this will modify expectations for the gravity wave signal. Indeed, in this
case, most of the kinetic energy is concentrated in the wall and almost no
turbulent fluid motions are expected since the surrounding fluid is kept mostly
at rest.Comment: 36 pages, 14 figure
Two-Higgs doublet models from TeV-scale supersymmetric extra U(1) models
We investigate the reduction of a general TeV-scale supersymmetric extra U(1)
model to a 2HDM below the TeV- scale through the tree level non-decoupling.
Portions of the parameter space of the extra U(1) model appropriate for
obtaining a 2HDM are identified. Various properties of the resulting 2HDM are
connected to the parameter space of the underlying model. PACS: 12.60.Jv,
12.60.Cn, 12.60.FrComment: 12 pages, 4 postscript figures, to appear in Phys. Rev.
Plant height and hydraulic vulnerability to drought and cold
Understanding how plants survive drought and cold is increasingly important as plants worldwide experience dieback with drought in moist places and grow taller with warming in cold ones. Crucial in plant climate adaptation are the diameters of water-transporting conduits. Sampling 537 species across climate zones dominated by angiosperms, we find that plant size is unambiguously the main driver of conduit diameter variation. And because taller plants have wider conduits, and wider conduits within species are more vulnerable to conduction-blocking embolisms, taller conspecifics should be more vulnerable than shorter ones, a prediction we confirm with a plantation experiment. As a result, maximum plant size should be short under drought and cold, which cause embolism, or increase if these pressures relax. That conduit diameter and embolism vulnerability are inseparably related to plant size helps explain why factors that interact with conduit diameter, such as drought or warming, are altering plant heights worldwide
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