1,579 research outputs found
QCD Phenomenology of Charm Production at HERA
We compare different schemes for the treatment of heavy quark production in
Deep-Inelastic Scattering (DIS). For fully-integrated quantities such as
, we advocate the use of the General-Massive
Variable-Flavor-Number (GM-VFN) scheme; we present some results showing the
progress of a Next-to-Leading Order calculation in this scheme. For
differential quantities, the Fixed-Flavor-Number (FFN) scheme provides a more
appropriate starting point. We present a new calculation of the azimuthal
distribution of charm quark production in DIS. All results have been obtained
using a Monte Carlo program under development.Comment: 5 pages, Latex/aipproc, 4 figures, presented at DIS 97, Chicago, IL,
April 14-18,199
Transverse Momentum Distributions in Large-rapidity Dijet Production at the Tevatron
In this contribution we examine the transverse momentum distributions in
dijet production at large rapidity intervals at the Tevatron, using the BFKL
resummation.Comment: 6 pages (1 uu-compressed encapsulated PS figure appended), DESY
94-163, SCIPP 94/2
Constraints on Little Higgs with Fully-Radiative Electroweak Symmetry Breaking
In a recent paper, we introduced a new Little Higgs model, which contains the
gauge structure , embedded in an approximate global
symmetry. After breaking to the standard model, , this produces two heavy bosons and two heavy
bosons, along with a single Standard Model-like Higgs scalar.
The unique feature of the model was that it was possible to obtain electroweak
symmetry breaking and a light Higgs mass entirely from perturbative loop
contributions to the Higgs effective potential. In this paper we consider the
electroweak constraints on this model, including tree and loop contributions to
the universal oblique and non-oblique parameters, tree-level corrections to the
vertex, and tree and loop level corrections to . The most
significant corrections are positive tree-level corrections to and
negative fermion-loop corrections to , which require that the scale
for the global symmetry breaking be TeV, depending on the top-quark
mixing parameter and the extra gauge couplings. In addition, the loop
corrections to contain a divergence that must be absorbed into the
coefficient of a new operator in the theory. The finite part of this
correction, however, is negligible.Comment: 28 pages, 16 figures, RevTeX forma
The Infrared Behavior of One-Loop Gluon Amplitudes at Next-to-Next-to-Leading Order
For the case of -jet production at next-to-next-to-leading order in the
QCD coupling, in the infrared divergent corners of phase space where particles
are collinear or soft, one must evaluate -parton final-state one-loop
amplitudes through \Ord(\eps^2), where \eps is the dimensional
regularization parameter. For the case of gluons, we present to all orders in
\eps the required universal functions which describe the behavior of one-loop
amplitudes in the soft and collinear regions of phase space. An explicit
example is discussed for three-parton production in multi-Regge kinematics that
has applications to the next-to-leading logarithmic corrections to the BFKL
equation.Comment: Latex, 14 pages, no figure
Update and review of the multidisciplinary management of stage IV colorectal cancer with liver metastases
<p>Abstract</p> <p>Background</p> <p>The management of stage IV colorectal cancer with liver metastases has historically involved a multidisciplinary approach. In the last several decades, there have been great strides made in the therapeutic options available to treat these patients with advancements in medical, surgical, locoregional and adjunctive therapies available to patients with colorectal liver metastases(CLM). As a result, there have been improvements in patient care and survival. Naturally, the management of CLM has become increasingly complex in coordinating the various aspects of care in order to optimize patient outcomes.</p> <p>Review</p> <p>A review of historical and up to date literature was undertaken utilizing Medline/PubMed to examine relevant topics of interest in patients with CLM including criterion for resectability, technical/surgical considerations, chemotherapy, adjunctive and locoregional therapies. This review explores the various disciplines and modalities to provide current perspectives on the various options of care for patients with CLM.</p> <p>Conclusion</p> <p>Improvements in modern day chemotherapy as allowed clinicians to pursue a more aggressive surgical approach in the management of stage IV colorectal cancer with CLM. Additionally, locoregional and adjunctive therapies has expanded the armamentarium of treatment options available. As a result, the management of patients with CLM requires a comprehensive, multidisciplinary approach utilizing various modalities and a more aggressive approach may now be pursued in patients with stage IV colorectal cancer with CLM to achieve optimal outcomes.</p
Gallus GBrowse: a unified genomic database for the chicken
Gallus GBrowse (http://birdbase.net/cgi-bin/gbrowse/gallus/) provides online access to genomic and other information about the chicken, Gallus gallus. The information provided by this resource includes predicted genes and Gene Ontology (GO) terms, links to Gallus In Situ Hybridization Analysis (GEISHA), Unigene and Reactome, the genomic positions of chicken genetic markers, SNPs and microarray probes, and mappings from turkey, condor and zebra finch DNA and EST sequences to the chicken genome. We also provide a BLAT server (http://birdbase.net/cgi-bin/webBlat) for matching user-provided sequences to the chicken genome. These tools make the Gallus GBrowse server a valuable resource for researchers seeking genomic information regarding the chicken and other avian species
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