630 research outputs found
TOP-INDUCED ELECTROWEAK BREAKING IN THE MINIMAL SUPERSYMMETRIC STANDARD MODEL
Severe constraints on parameters of the minimal supersymmetric standard model
follow from a dynamical electroweak symmetry breaking mechanism dominated by
top and stop loops. In particular, the lightest Higgs boson mass is expected to
be smaller than 100 GeV.Comment: 10 pages, Latex, 6 Postcript Figure
Clinical significance of epithelial-to-mesenchymal transition in laryngeal carcinoma: Its role in the different subsites
Background: During epithelial-to-mesenchymal transition, cancer cells lose adhesion capacity gaining migratory properties. The role of the process on prognosis has been evaluated in 50 cases of laryngeal carcinoma. Methods: E-cadherin, N-cadherin, β-catenin, α-catenin, γ-catenin, caveolin-1, and vimentin immunohistochemical expression were evaluated using a double score based on staining intensity and cellular localization. Results: Cytoplasmic E-cadherin and α/γ catenin staining were associated with a decrease in survival, cytoplasmic β-catenin was associated with advanced stage, and N-cadherin and vimentin expression were associated with poor differentiation and tumor relapse. On the basis of cancer cells, epithelial or mesenchymal morphological and immunophenotypic similarity we identified 4 main subgroups correlated with a transition to a more undifferentiated phenotype, which have a different pattern of relapse and survival. Conclusion: The negative prognostic role of epithelial-to-mesenchymal transition has been confirmed and a predictive role in glottic tumors has been suggested, leading us to propose epithelial-to-mesenchymal transition as an additional adverse feature in laryngeal carcinoma
Top Quark Production in Extended Bess Model
We study top production at Tevatron collider in the extended BESS model,
which is an effective lagrangian parametrization of a dynamical symmetry
breaking of the electroweak symmetry. The existence of a colored octet of gauge
vector bosons can increase top production at a rate still consistent with
recent experimental data and lead to distorsions in the transverse momentum
spectrum of the top.Comment: 13 pages, LaTeX, 4 figure
KMT2C modulates migration and invasion processes in osteosarcoma cell lines
In this study we investigated the role of KMT2C (a chromatin-modifying and remodelling protein) in osteosarcoma progression through cell migration and invasion assays in osteosarcoma primary and metastatic cell lines. Wound healing and transwell assays were used to detect changes of cell migration and matrigel assay was used to evaluate changes of cell invasion in primary and metastatic osteosarcoma cell lines after KMT2C siRNA transfection. We found that primary osteosarcoma cell lines showed the highest capacity of migration before mRNA KMT2C silencing and the highest capacity of invasion after mRNA KMT2C silencing; on the contrary, osteosarcoma metastatic cell line showed the highest capacity of migration after mRNA KMT2C silencing and the highest capacity of invasion before mRNA KMT2C silencing. Our study supports data in favour of selective enhancer changes, KMT2C-mediated, in metastatic osteosarcoma probably due to the different microenvironment between primary and metastatic sites
Pseudo Goldstones at Future Colliders from the Extended Bess Model
We consider the production of the lightest pseudo-Goldstone bosons at future
colliders through the vector resonances predicted by the extended BESS model,
which consists of an effective lagrangian parametrization with dynamical
symmetry breaking, describing scalar, vector and axial-vector bound states in a
rather general framework. We find that the detection of pseudo-Goldstone pairs
at LHC requires a careful evaluation of backgrounds. For e+e- collisions in the
TeV range the backgrounds can be easily reduced and the detection of
pseudo-Goldstone pairs is generally easier.Comment: 17 pages and 12 figures (included as a uuencoded tar file), LaTeX
(style article), UGVA-DPT 1994/03-84
Higher Twist Effects in the Drell-Yan Angular Distribution
We study the Drell-Yan process at large
using perturbative QCD. A higher-twist mechanism suggested by Berger and
Brodsky is known to qualitatively explain the observed dependence of the
muon angular distribution, but the predicted large behavior differs
quantitatively from observations. We have repeated the model calculation taking
into account the effects of nonasymptotic kinematics. At fixed-target energies
we find important corrections which improve the agreement with data. The
asymptotic result of Berger and Brodsky is recovered only at much higher
energies. We discuss the generic reasons for the large corrections at high
. A proper understanding of the data would give important
information on the pion distribution amplitude and exclusive form factor.Comment: 8 pages in Latex with 3 figures appended as Postscript files,
HU-TFT-94-12, LBL-35430. (The introductory part has been slightly altered and
three references have been added
An NLO calculation of the electroproduction of large-E_\bot hadrons
We present a Next-to-Leading Order calculation of the cross section for the
leptoproduction of large- hadrons and we compare our predictions with
H1 data on the forward production of . We find large higher order
corrections and an important sensitivity to the renormalization and
factorization scales. These large corrections are shown to arise in part from
BFKL-like diagrams at the lowest order.Comment: 24 pages, plain LaTeX2e, 10 figure
Beam polarization at LHC and SSC. Expected asymmetries in the Bess model and comparison with other models
In view of recent and foreseen technical advances in beam polarization in future proton colliders we discuss possible tests of non-standard physics at LHC and SSC assuming initial proton polarization, specifically to test for a strong electroweak sector and compairing with different extended gauge models. We examine lepton pair production, studying left-right and forward-backward asymmtries, assuming quark-antiquark and WW fusion production mechanisms. We discuss the uncertainties related to polarized proton structure functions
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