2,438 research outputs found
Evaluation of the Free Energy of Two-Dimensional Yang-Mills Theory
The free energy in the weak-coupling phase of two-dimensional Yang-Mills
theory on a sphere for SO(N) and Sp(N) is evaluated in the 1/N expansion using
the techniques of Gross and Matytsin. Many features of Yang-Mills theory are
universal among different gauge groups in the large N limit, but significant
differences arise in subleading order in 1/N.Comment: 10 pages; no figures; LaTe
Social and political mechanisms for establishing ecosystem management objectives
While social values guide the objectives of ecosystem management, successful execution requires a public well-informed on the consequences of alternative decision options. Daniels advocates a group-learning process entitled collaborative learning to achieve this understanding. Agency personnel should assume the roles of educators, facilitators, and managers. The agencies must also open up, meditate, and share decision-making power with the public while avoiding advocacy of any particular interest-group\u27s desires. Policy makers have a role in influencing social values by fostering a nonadversarial politics of cooperation and consensus building
Dynamics at barriers in bidirectional two-lane exclusion processes
A two-lane exclusion process is studied where particles move in the two lanes
in opposite directions and are able to change lanes. The focus is on the steady
state behavior in situations where a positive current is constrained to an
extended subsystem (either by appropriate boundary conditions or by the
embedding environment) where, in the absence of the constraint, the current
would be negative. We have found two qualitatively different types of steady
states and formulated the conditions of them in terms of the transition rates.
In the first type of steady state, a localized cluster of particles forms with
an anti-shock located in the subsystem and the current vanishes exponentially
with the extension of the subsystem. This behavior is analogous to that of the
one-lane partially asymmetric simple exclusion process, and can be realized
e.g. when the local drive is induced by making the jump rates in two lanes
unequal. In the second type of steady state, which is realized e.g. if the
local drive is induced purely by the bias in the lane change rates, and which
has thus no counterpart in the one-lane model, a delocalized cluster of
particles forms which performs a diffusive motion as a whole and, as a
consequence, the current vanishes inversely proportionally to the extension of
the subsystem. The model is also studied in the presence of quenched
disordered, where, in case of delocalization, phenomenological considerations
predict anomalously slow, logarithmic decay of the current with the system size
in contrast with the usual power-law.Comment: 24 pages, 13 figure
Epirubicin With Cyclophosphamide Followed by Docetaxel With Trastuzumab and Bevacizumab as Neoadjuvant Therapy for HER2-Positive Locally Advanced Breast Cancer or as Adjuvant Therapy for HER2-Positive Pathologic Stage III Breast Cancer: A Phase II Trial of the NSABP Foundation Research Group, FB-5
Background The purpose of this study was to determine the cardiac safety and clinical activity of trastuzumab and bevacizumab with docetaxel after epirubicin with cyclophosphamide (EC) in patients with HER2-positive locally advanced breast cancer (LABC) or pathologic stage 3 breast cancer (PS3BC). Patients and Methods Patients received every 3 week treatment with 4 cycles of EC (90/600 mg/m2) followed by 4 cycles of docetaxel (100 mg/m2). Targeted therapy with standard-dose trastuzumab with bevacizumab 15 mg/kg was given for a total of 1 year. Coprimary end points were (1) rate of cardiac events (CEs) in all patients defined as clinical congestive heart failure with a significant decrease in left ventricular ejection fraction or cardiac deaths; and (2) pathologic complete response (pCR) in breast and nodes in the neoadjuvant cohort. An independent cardiac review panel determined whether criteria for a CE were met. Results A total of 105 patients were accrued, 76 with LABC treated with neoadjuvant therapy and 29 with PS3BC treated with adjuvant therapy. Median follow-up was 59.2 months. Among 99 evaluable patients for cardiac safety, 4 (4%; 95% confidence interval [CI], 1.1%-10.0%) met CE criteria. The pCR percentage in LABC patients was 46% (95% CI, 34%-59%). Five-year recurrence-free survival (RFS) and overall survival (OS) for all patients was 79.9% and 90.8%, respectively. Conclusion The regimen met predefined criteria for activity of interest with an acceptable rate of CEs. Although the pCR percentage was comparable with chemotherapy regimens with trastuzumab alone the high RFS and OS are of interest in these high-risk populations
Mean field treatment of exclusion processes with random-force disorder
The asymmetric simple exclusion process with random-force disorder is studied
within the mean field approximation. The stationary current through a domain
with reversed bias is analyzed and the results are found to be in accordance
with earlier intuitive assumptions. On the grounds of these results, a
phenomenological random barrier model is applied in order to describe
quantitatively the coarsening phenomena. Predictions of the theory are compared
with numerical results obtained by integrating the mean field evolution
equations.Comment: 21 pages, 14 figure
Ab-Initio Calculation of Molecular Aggregation Effects: a Coumarin-343 Case Study
We present time-dependent density functional theory (TDDFT) calculations for
single and dimerized Coumarin-343 molecules in order to investigate the quantum
mechanical effects of chromophore aggregation in extended systems designed to
function as a new generation of sensors and light-harvesting devices. Using the
single-chromophore results, we describe the construction of effective
Hamiltonians to predict the excitonic properties of aggregate systems. We
compare the electronic coupling properties predicted by such effective
Hamiltonians to those obtained from TDDFT calculations of dimers, and to the
coupling predicted by the transition density cube (TDC) method. We determine
the accuracy of the dipole-dipole approximation and TDC with respect to the
separation distance and orientation of the dimers. In particular, we
investigate the effects of including Coulomb coupling terms ignored in the
typical tight-binding effective Hamiltonian. We also examine effects of orbital
relaxation which cannot be captured by either of these models
The Reach of CERN LEP2 and Fermilab Tevatron Upgrades for Higgs Bosons in Supersymmetric Models
Luminosity upgrades of the Fermilab Tevatron pbar-p collider have been shown
to allow experimental detection of a Standard Model (SM) Higgs boson up to
GeV via events. This limit
nearly saturates the parameter space for many models of weak scale
supersymmetry (SUSY) with a minimal particle content. It is therefore
interesting to examine the SUSY Higgs reach of future Tevatron experiments.
Contours are presented of Higgs boson reach for CERN LEP2 and Tevatron
luminosity upgrades for three models of weak scale SUSY: the Minimal
Supersymmetric Standard Model (MSSM), the minimal Supergravity model (mSUGRA)
and a simple Gauge Mediated SUSY Breaking Model (GMSB). In each case we find a
substantial gain in reach at the Tevatron with integrated luminosity increasing
from 10 fb^{-1} to 25-30 fb^{-1}. With the larger integrated luminosity, a
Higgs search at the Tevatron should be able to probe essentially the entire
parameter space of these models. While a discovery would be very exciting, a
negative result would severely constrain our ideas about how weak scale
supersymmetry is realized.Comment: 12 pages + 7 figures. Uses REVTEX and epsf macros. Several references
added, stated value of A-parameters corrected, note added reguarding sgn(mu)
dependence in MSSM case. To appear in Physical Review
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Insiders, Outsiders, and the Struggle for Consecration in Cultural Fields: A Core-Periphery Perspective
Building on recent research emphasizing how legitimacy depends on consensus among audiences about candidatesâ characteristics and activities, we examine the relationship between cultural producersâ (candidates) position in the social structure and the consecration of their creative work by relevant audiences. We argue that the outcome of this process of evaluation in any cultural field, whether in art or science, is a function of (1) candidatesâ embeddedness within the field, and (2) the type of audienceâthat is, peers versus criticsâevaluating candidatesâ work. Specifically, we hypothesize that peers are more likely to favor candidates who are highly embedded in the field, whereas critics will not show such favoritism. We find support for these hypotheses in the context of the Hollywood motion picture industry
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